Sample records for nerc sub region

  1. North American Electric Reliability Corporation (NERC): Reliability...

    Office of Environmental Management (EM)

    (NERC): Reliability Considerations from the Integration of Smart Grid North American Electric Reliability Corporation (NERC): Reliability Considerations from the Integration of...

  2. Energy Efficiency in Western Utility Resource Plans: Impacts on Regional Resources Assessment and Support for WGA Policies

    E-Print Network [OSTI]

    Hopper, Nicole; Goldman, Charles; Schlegal, Jeff

    2006-01-01T23:59:59.000Z

    PNM PSCO PSE PUC SDG&E SCE WECC average megawatts Britishwith appropriate NERC and WECC committees and subcommitteesconsistent across NERC, WECC and state/regional assessments

  3. USING NERC SCIENCE Welcome to the latest edition of the Natural Environment Research Council (NERC)

    E-Print Network [OSTI]

    Williams, Paul

    /events/090424/. The application deadline is 15 April 2009. UK Energy Research Centre (UKERC) One day event investigation of energy in the UK. NERC is a part funder of UKERC. For more information and to register, go to, atmospheric sciences, geo- and palaeochemistry, marine biogeochemistry, geophysics, ecology, solar

  4. Who we are NERC the Natural Environment Research

    E-Print Network [OSTI]

    Brierley, Andrew

    of research on your business NERC research enables safe and efficient access to the natural resources on which with business Improving competitiveness NERC climate science helps improve the catastrophe modelling all businesses depend. Our modelling of environmental hazards helps industry mitigate and adapt

  5. Regional Interagency Steering GIS Sub-Committee for FEMA's Region II Caribbean Area Division

    E-Print Network [OSTI]

    Gilbes, Fernando

    Regional Interagency Steering GIS Sub-Committee for FEMA's Region II Caribbean Area Division Jimmy Rodríguez-Zamora Caribbean Area Division, San Juan, Puerto Rico 00918 Department of Homeland Security also. This effort is being carried out at the Caribbean Area Division as New York and New Jersey

  6. Property:EIA/861/NercFrcc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,PillarPublicationType JumpDOEInvolve JumpallowedAltFuelVehicle JumpIsoNyNercFrcc

  7. Property:EIA/861/NercRfc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,PillarPublicationType JumpDOEInvolve JumpallowedAltFuelVehicleNercRfc Jump to:

  8. Property:EIA/861/NercSpp | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,PillarPublicationType JumpDOEInvolve JumpallowedAltFuelVehicleNercRfc Jump

  9. Property:EIA/861/NercLocation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid Jump to: navigation,AltFuelVehicle2 Jump to:NercLocation

  10. Property:EIA/861/NercSerc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid Jump to: navigation,AltFuelVehicle2 JumpNercSerc Jump

  11. Property:EIA/861/NercWecc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid Jump to: navigation,AltFuelVehicle2 JumpNercSerc

  12. Photodissociation dynamics of C{sub 3}H{sub 5}I in the near-ultraviolet region

    SciTech Connect (OSTI)

    Sumida, Masataka; Hanada, Takuya; Yamasaki, Katsuyoshi; Kohguchi, Hiroshi, E-mail: kohguchi@hiroshima-u.ac.jp [Department of Chemistry, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)

    2014-09-14T23:59:59.000Z

    The ultraviolet photodissociation dynamics of allyl iodide (C{sub 3}H{sub 5}I) have been studied by ion-imaging at 266 nm and 213 nm. These photolysis wavelengths are located in the two lowest absorption bands in the near-ultraviolet region. The atomic iodine products were detected by [2+1] resonantly enhanced multiphoton ionization spectroscopy. The spectra showed that the branching fraction for the spin-orbit excited ({sup 2}P{sub 1/2}) state was larger than that for the ground ({sup 2}P{sub 3/2}) state at both photolysis wavelengths. The state-resolved scattering images of iodine showed two maxima in the velocity distributions in the {sup 2}P{sub 3/2} state and a single peak in the {sup 2}P{sub 1/2} state. The spin-orbit specificity indicates that the C?I bond cleavage at both absorption bands is governed by the dissociative n{sub I}?{sup *}{sub C?I} potential energy surfaces. The nascent internal energy distribution of the allyl radical (C{sub 3}H{sub 5}) counter product, which was obtained by the analysis of the state-resolved scattering distributions, showed a marked difference between the photolysis at 266 nm and 213 nm. The generation of the colder C{sub 3}H{sub 5} with the higher translational energy at 266 nm implied the direct photoexcitation to the n{sub I}?{sup *}{sub C?I} repulsive surfaces, whereas the internally hot C{sub 3}H{sub 5} at 213 nm was ascribed to the local ?{sub CC}?{sup *}{sub CC} photoinitiation in the allyl framework followed by predissociation to the n{sub I}?{sup *}{sub C?I} states.

  13. Investigation on transition behavior and electrical properties of (K{sub 0.5}Na{sub 0.5}){sub 1-x}Li{sub x}Nb{sub 0.84}Ta{sub 0.1}Sb{sub 0.06}O{sub 3} around polymorphic phase transition region

    SciTech Connect (OSTI)

    Zhu, Chen; Wang, Wenchao; Shi, Honglin; Wang, Fangyu; Cao, Yongge [Department of Physics, Renmin University of China, Beijing 100872, P R China (China) [Department of Physics, Renmin University of China, Beijing 100872, P R China (China); Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China); Huang, Jiquan; Wang, Chong [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China)] [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China); Tang, Fei; Yuan, Xuanyi, E-mail: yuanxuanyi@ruc.edu.cn [Department of Physics, Renmin University of China, Beijing 100872, P R China (China)] [Department of Physics, Renmin University of China, Beijing 100872, P R China (China); Liu, Yang [School of Chemistry and Environment Engineering, Shaoguan University, Shaoguan 512005 (China)] [School of Chemistry and Environment Engineering, Shaoguan University, Shaoguan 512005 (China)

    2014-01-15T23:59:59.000Z

    (K{sub 0.5}Na{sub 0.5}){sub 1-x}Li{sub x}Nb{sub 0.84}Ta{sub 0.1}Sb{sub 0.06}O{sub 3} (KNLNTS) lead free ceramics with different Li concentration were fabricated by conventional solid-state reaction method. By increasing Li ions in KNLNTS, the grains grow up and the crystal structure changes from orthorhombic to tetragonal. When 0.03 ? x ? 0.05, the ceramics structure lays in PPT region. Polarization versus electric field (P-E) hysteresis loops at room temperature show good ferroelectric properties and the remnant polarization decreases by increasing Li content while coercive electric keeps almost unchanged. In PPT region, taking x = 0.04 as an example, the sample shows excellent dielectric properties: the dielectric constant is 1159 and loss tangent is 0.04, while the piezoelectric constant d{sub 33} is 245 pC/N and kp is 0.44 at room temperature, it is promising for (K{sub 0.5}Na{sub 0.5}){sub 1-x}Li{sub x}Nb{sub 0.84}Ta{sub 0.1}Sb{sub 0.06}O{sub 3} with 4 at. % Li to substitute PZT.

  14. Regional partnerships to sequester CO{sub 2} at near-commercial scale

    SciTech Connect (OSTI)

    NONE

    2008-07-01T23:59:59.000Z

    A summary of the keynote speech by Acting Deputy Secretary of Energy, Jeffrey Kupfer, is given, as well as details about new agreements on CO{sub 2} injection. These include the West Coast Regional Carbon Sequestration Partnership agreement to locate CO{sub 2} injection with a 50 mw clean energy systems plant in Kumberlina, California, and the Plains CO{sub 2} Reduction Partnership and Southeast Regional Carbon Sequestration PARTNERSHIP plans to inject CO{sub 2} derived from post combustion capture at power plants. 3 photos.

  15. OPTICAL CONSTANTS OF NH{sub 3} AND NH{sub 3}:N{sub 2} AMORPHOUS ICES IN THE NEAR-INFRARED AND MID-INFRARED REGIONS

    SciTech Connect (OSTI)

    Zanchet, Alexandre; Rodríguez-Lazcano, Yamilet; Gálvez, Óscar; Herrero, Víctor J.; Escribano, Rafael; Maté, Belén, E-mail: belen.mate@csic.es [Instituto de Estructura de la Materia, IEM-CSIC, Serrano 123, E-28006 Madrid (Spain)

    2013-11-01T23:59:59.000Z

    Ammonia ice has been detected on different astrophysical media ranging from interstellar medium (ISM) particles to the surface of various icy bodies of our solar system, where nitrogen is also present. We have carried out a detailed study of amorphous NH{sub 3} ice and NH{sub 3}:N{sub 2} ice mixtures, based on infrared (IR) spectra in the mid-IR (MIR) and near-IR (NIR) regions, supported by theoretical quantum chemical calculations. Spectra of varying ice thicknesses were obtained and optical constants were calculated for amorphous NH{sub 3} at 15 K and 30 K and for a NH{sub 3}:N{sub 2} mixture at 15 K over a 500-7000 cm{sup –1} spectral range. These spectra have improved accuracy over previous data, where available. Moreover, we also obtained absolute values for the band strengths of the more prominent IR features in both spectral regions. Our results indicate that the estimated NH{sub 3} concentration in ISM ices should be scaled upward by ?30%.

  16. New combination bands of N{sub 2}O-CO{sub 2}, N{sub 2}O-OCS, and N{sub 2}O-N{sub 2} complexes in the N{sub 2}O ?{sub 1} region

    SciTech Connect (OSTI)

    Rezaei, M.; Moazzen-Ahmadi, N., E-mail: ahmadi@phas.ucalgary.ca [Department of Physics and Astronomy, University of Calgary, 2500 University Drive North West, Calgary, Alberta T2N 1N4 (Canada); Michaelian, K. H. [Natural Resources Canada, CanmetENERGY, 1 Oil Patch Drive, Suite A202, Devon, Alberta T9G 1A8 (Canada)] [Natural Resources Canada, CanmetENERGY, 1 Oil Patch Drive, Suite A202, Devon, Alberta T9G 1A8 (Canada)

    2014-01-28T23:59:59.000Z

    Spectra of the weakly bound complexes N{sub 2}O-CO{sub 2}, N{sub 2}O-OCS, and N{sub 2}O-N{sub 2} were studied in the region of the ?{sub 1} fundamental of N{sub 2}O (?2224 cm{sup ?1}) using a tunable quantum cascade laser to probe a pulsed supersonic jet expansion with an effective rotational temperature of about 2.5 K. One new combination band was observed for each complex: a band involving an intermolecular in-plane bending mode for N{sub 2}O-N{sub 2}, a band involving the disrotation (in-plane geared bend) for of N{sub 2}O-CO{sub 2}, and a band involving the out-of-plane torsional vibration for isomer b of N{sub 2}O-OCS. Small perturbations were noted for the N{sub 2}O-OCS band. Because of the absence of theoretical prediction, the nature of the intermolecular bending mode for N{sub 2}O-N{sub 2} has not been identified. The resulting intermolecular frequencies are 34.175(1), 17.107(1), and 22.334(1) cm{sup ?1} for N{sub 2}O-CO{sub 2}, N{sub 2}O-OCS, and N{sub 2}O-N{sub 2}, respectively. In addition, the previously known fundamental band of N{sub 2}O-N{sub 2} at 2225.99 cm{sup ?1} was analyzed in improved detail. This band exhibits very weak a-type transitions which were not detected in the first infrared observation of this complex, indicating that N{sub 2}O-N{sub 2} is not exactly T-shaped. That is, the N{sub 2}O molecular axis is not exactly perpendicular to the a-inertial axis, in agreement with a previous structural determination of this complex by rotational spectroscopy.

  17. Rocky Mountain Regional CO{sub 2} Storage Capacity and Significance

    SciTech Connect (OSTI)

    Laes, Denise; Eisinger, Chris; Esser, Richard; Morgan, Craig; Rauzi, Steve; Scholle, Dana; Matthews, Vince; McPherson, Brian

    2013-08-30T23:59:59.000Z

    The purpose of this study includes extensive characterization of the most promising geologic CO{sub 2} storage formations on the Colorado Plateau, including estimates of maximum possible storage capacity. The primary targets of characterization and capacity analysis include the Cretaceous Dakota Formation, the Jurassic Entrada Formation and the Permian Weber Formation and their equivalents in the Colorado Plateau region. The total CO{sub 2} capacity estimates for the deep saline formations of the Colorado Plateau region range between 9.8 metric GT and 143 metric GT, depending on assumed storage efficiency, formations included, and other factors.

  18. NERC 101

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade1 Source: Office of FossilFoot) Year JanCubicXIV.Mr.NEMS

  19. "Interconnection","NERC Regional Assesment Area"

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells,1Stocksa. AppliancesTotal" "(Data from03.4

  20. "Interconnection","NERC Regional Assesment Area","Summer"

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells,1Stocksa. AppliancesTotal" "(Data from03.4B Winter net2.

  1. "January","NERC Regional Assesment Area"

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells,1Stocksa. AppliancesTotal" "(Data from03.4B Winter net2.A.1.

  2. www.planetearth.nerc.ac.uk Autumn 2014 Trout in hot water Biodiversity and big data Bioenergy's carbon footprint Sustainable drainage

    E-Print Network [OSTI]

    Brierley, Andrew

    's carbon footprint · Sustainable drainage Intothe #12;Front cover image courtesy Ben Langford About us NERC to account ­ bioenergy's carbon footprint What's the true cost of growing our fuel? 22 The science

  3. Functional analysis of the NH{sub 2}-terminal hydrophobic region and BRICHOS domain of GKN1

    SciTech Connect (OSTI)

    Yoon, Jung Hwan; Choi, Yoo Jin; Choi, Won Suk; Nam, Suk Woo; Lee, Jung Young; Park, Won Sang, E-mail: wonsang@catholic.ac.kr

    2013-11-01T23:59:59.000Z

    Highlights: •NH{sub 2}-terminal and BRICHOS domain of GKN1 inhibited tumor cell growth. •NH{sub 2}-terminal and BRICHOS domain of GKN1 regulated cell cycle. •NH{sub 2}-terminal and BRICHOS domain of GKN1 inhibited epigenetic regulators. -- Abstract: Gastrokine 1 (GKN1) protects the gastric antral mucosa and promotes healing by facilitating restitution and proliferation after injury. GKN1 is down-regulated in Helicobacter pylori-infected gastric epithelial cells and loss of GKN1 expression is tightly associated with gastric carcinogenesis. However, the underlying mechanisms as a tumor suppressor are largely unknown. Presently, the hydrophobic region and BRICHOS domain of GKN1, pGKN1{sup D13N}, pGKN1{sup ?68–199}, and pGKN1{sup ?1–67,165–199} were shown to suppress gastric cancer cell growth and recapitulate GKN1 functions. As well, the hydrophobic region and BRICHOS domain of GKN1 had a synergistic anti-cancer effect with 5-FU on tumor cell growth, implying that the NH{sub 2}-terminal hydrophobic region and BRICHOS domain of GKN1 are sufficient for tumor suppression, thereby suggesting a therapeutic intervention for gastric cancer. Also, its domain inducing endogenous miR-185 directly targeted the epigenetic effectors DNMT1 and EZH2 in gastric cancer cells. Our results suggest that the NH{sub 2}-terminal hydrophobic region and BRICHOS domain of GKN1 are sufficient for its tumor suppressor activities.

  4. Applicability of the “Gallet equation” to the vegetation clearances of NERC Reliability Standard FAC-003-2

    SciTech Connect (OSTI)

    Kirkham, Harold

    2012-03-31T23:59:59.000Z

    NERC has proposed a standard to use to specify clearances between vegetation and power lines. The purpose of the rule is to reduce the probability of flashover to a calculably low level. This report was commissioned by FERC’s Office of Electrical Reliability. The scope of the study was analysis of the mathematics and documentation of the technical justification behind the application of the Gallet equation and the assumptions used in the technical reference paper

  5. {beta}{sub {beta}} measurements of neutron-rich isotopes in the mass region 147{le}A{le}152

    SciTech Connect (OSTI)

    Ikuta, T.; Taniguchi, A.; Yamamoto, H.; Kawade, K. [Nagoya Univ. (Japan); Kawase, Y. [Kyoto Univ., Osaka (Japan)

    1994-12-31T23:59:59.000Z

    The systematic Q{sub {beta}} measurements of 14 neutron-rich nuclei in the mass region from A=147 to A=152 have been performed with an HPGe detector. Neutron-rich nuclei were mass-separated from the thermal neutron induced fission of {sup 235}U using a He-N{sub 2} mixture-jet type on-line isotope separator which has been developed at the Kyoto University Reactor (KUR-ISOL). From a {beta}-ray singles and {beta}-{gamma} coincidence measurements, the Q{sub {beta}} values of {sup 147}La, {sup 147-150}Ce, {sup 147-152}Pr, {sup 152}Nd and {sup 152}Pm have been determined. In addition, the atomic masses derived from the experimental Q{sub {beta}} values are compared with the predictions of theoretical mass calculations.

  6. REGIONES EMERGENTES EN URUGUAY, SUB-REGIN PLATA-MERCOSUR (NOUVEAUX TERRITOIRES EN URUGUAY, SOUS-RGION

    E-Print Network [OSTI]

    1 REGIONES EMERGENTES EN URUGUAY, SUB-REGI�N PLATA- MERCOSUR (NOUVEAUX TERRITOIRES EN URUGUAY, SOUS, Uruguay halshs-00960472,version1-10Jun2014 Author manuscript, published in "1ère Conférence continuidad institucional del acuerdo del MERCOSUR como tal, sobre todo por la tensión entre Uruguay y

  7. Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France and

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France Introduction Renewable energy sources such as biomass and biofuels are increasingly being seen as important of biofuels on the final consumption of energy in transport should be 10%. The long-term target is to reduce

  8. Reactive power interconnection requirements for PV and wind plants : recommendations to NERC.

    SciTech Connect (OSTI)

    McDowell, Jason (General Electric, Schenectady, NY); Walling, Reigh (General Electric, Schenectady, NY); Peter, William (SunPower, Richmond, CA); Von Engeln, Edi (NV Energy, Reno, NV); Seymour, Eric (AEI, Fort Collins, CO); Nelson, Robert (Siemens Wind Turbines, Orlando, FL); Casey, Leo (Satcon, Boston, MA); Ellis, Abraham; Barker, Chris. (SunPower, Richmond, CA)

    2012-02-01T23:59:59.000Z

    Voltage on the North American bulk system is normally regulated by synchronous generators, which typically are provided with voltage schedules by transmission system operators. In the past, variable generation plants were considered very small relative to conventional generating units, and were characteristically either induction generator (wind) or line-commutated inverters (photovoltaic) that have no inherent voltage regulation capability. However, the growing level of penetration of non-traditional renewable generation - especially wind and solar - has led to the need for renewable generation to contribute more significantly to power system voltage control and reactive power capacity. Modern wind-turbine generators, and increasingly PV inverters as well, have considerable dynamic reactive power capability, which can be further enhanced with other reactive support equipment at the plant level to meet interconnection requirements. This report contains a set of recommendations to the North-America Electricity Reliability Corporation (NERC) as part of Task 1-3 (interconnection requirements) of the Integration of Variable Generation Task Force (IVGTF) work plan. The report discusses reactive capability of different generator technologies, reviews existing reactive power standards, and provides specific recommendations to improve existing interconnection standards.

  9. Novel concepts of superconductive optoelectronic devices: Resonances of photoconductivity in the Cu{sub 2}O gate region

    SciTech Connect (OSTI)

    Masumi, Taizo; Isobe, Masakatsu [Gunma Univ., Kiryu, Gunma (Japan). Dept. of Electronic Engineering

    1996-12-31T23:59:59.000Z

    On the basis of the discoveries of anomalous photoconductivity of insulators correlated with high-{Tc} superconductivity, the authors introduce novel concepts of superconductive optoelectronic devices. They have proposed that one must be able to fabricate a new type of device by combining these photoconductors for the gate region and relevant superconductors for the source and drain regions, both effective below their Tc`s. They have been continuing a series of further experimental studies seeking actual possibilities by utilizing the basic substance Cu{sub 2}O for the gate material and superconductive LBCO, LSCO and YBCO for the source and drain materials, e.g., YBCO/Cu{sub 2}O/YBCO. Here, they report an observation of resonant and hybrid emergences of photoconductivity of Cu{sub 2}O in the gate region peculiarly in conjugation with the high-Tc superconductivity utilized in the source and drain regions in superconductive optoelectronic devices. Microwave photosignals at 35 GHz guarantee a high-speed operation of the device in the n-sec region. They feed these results in a Nano-engineering back to basic Physics of Oxide Superconductor in order to shed a new light on substantial natures of the Cu-O based high-{Tc} superconductivity.

  10. SIMULATION FRAMEWORK FOR REGIONAL GEOLOGIC CO{sub 2} STORAGE ALONG ARCHES PROVINCE OF MIDWESTERN UNITED STATES

    SciTech Connect (OSTI)

    Sminchak, Joel

    2012-09-30T23:59:59.000Z

    This report presents final technical results for the project Simulation Framework for Regional Geologic CO{sub 2} Storage Infrastructure along Arches Province of the Midwest United States. The Arches Simulation project was a three year effort designed to develop a simulation framework for regional geologic carbon dioxide (CO{sub 2}) storage infrastructure along the Arches Province through development of a geologic model and advanced reservoir simulations of large-scale CO{sub 2} storage. The project included five major technical tasks: (1) compilation of geologic, hydraulic and injection data on Mount Simon, (2) development of model framework and parameters, (3) preliminary variable density flow simulations, (4) multi-phase model runs of regional storage scenarios, and (5) implications for regional storage feasibility. The Arches Province is an informal region in northeastern Indiana, northern Kentucky, western Ohio, and southern Michigan where sedimentary rock formations form broad arch and platform structures. In the province, the Mount Simon sandstone is an appealing deep saline formation for CO{sub 2} storage because of the intersection of reservoir thickness and permeability. Many CO{sub 2} sources are located in proximity to the Arches Province, and the area is adjacent to coal fired power plants along the Ohio River Valley corridor. Geophysical well logs, rock samples, drilling logs, and geotechnical tests were evaluated for a 500,000 km{sup 2} study area centered on the Arches Province. Hydraulic parameters and historical operational information was also compiled from Mount Simon wastewater injection wells in the region. This information was integrated into a geocellular model that depicts the parameters and conditions in a numerical array. The geologic and hydraulic data were integrated into a three-dimensional grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO{sub 2} injection. Permeability data were corrected in locations where reservoir tests have been performed in Mount Simon injection wells. The geocellular model was used to develop a series of numerical simulations designed to support CO{sub 2} storage applications in the Arches Province. Variable density fluid flow simulations were initially run to evaluate model sensitivity to input parameters. Two dimensional, multiple-phase simulations were completed to evaluate issues related to arranging injection fields in the study area. A basin-scale, multiple-phase model was developed to evaluate large scale injection effects across the region. Finally, local scale simulations were also completed with more detailed depiction of the Eau Claire formation to investigate to the potential for upward migration of CO{sub 2}. Overall, the technical work on the project concluded that injection large-scale injection may be achieved with proper field design, operation, siting, and monitoring. Records from Mount Simon injection wells were compiled, documenting more than 20 billion gallons of injection into the Mount Simon formation in the Arches Province over the past 40 years, equivalent to approximately 60 million metric tons CO2. The multi-state team effort was useful in delineating the geographic variability in the Mount Simon reservoir properties. Simulations better defined potential well fields, well field arrangement, CO{sub 2} pipeline distribution system, and operational parameters for large-scale injection in the Arches Province. Multiphase scoping level simulations suggest that injection fields with arrays of 9 to 50+ wells may be used to accommodate large injection volumes. Individual wells may need to be separated by 3 to 10 km. Injection fields may require spacing of 25 to 40 km to limit pressure and saturation front interference. Basin-scale multiple-phase simulations in STOMP reflect variability in the Mount Simon. While simulations suggest a total injection rate of 100 million metric tons per year (approximately to a 40% reduction of CO{sub 2} emissions from large point sources across the Arches Pr

  11. Vector analyzing power of {pi}{sup +7}Li scattering in the region of the {delta}{sub 33} resonance

    SciTech Connect (OSTI)

    Ibraeva, E. T. [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan); Zhusupov, M. A. [Kazakh State University, Institute of Experimental and Theoretical Physics (Kazakhstan); Zaykin, A. Yu. [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan); Imambekov, O. [Kazakh State University, Institute of Experimental and Theoretical Physics (Kazakhstan)

    2006-04-15T23:59:59.000Z

    Within Glauber diffraction theory, the vector analyzing power iT{sub 11} is calculated at three energies of positively charged pions, 134, 164, and 194 MeV, incident to {sup 7}Li nuclei. These energy values lie in the region of the {delta}{sub 33} resonance in {pi}{sup {+-}}N interaction, the resonance maximum being at 180 MeV. The calculation of iT{sub 11} was performed with several model {sup 7}Li wave functions, including the {alpha}t-cluster and shell-model ones. The properties of {pi}{sup +7}Li scattering are found to be sensitive to the structural features of the target nucleus. A comparison of the results of the calculations with experimental data shows that the wave functions in question and the potentials used to calculate them are quite appropriate.

  12. Electronic state spectroscopy of diiodomethane (CH{sub 2}I{sub 2}): Experimental and computational studies in the 30?000–95?000 cm{sup ?1} region

    SciTech Connect (OSTI)

    Mandal, Anuvab; Jagatap, B. N., E-mail: bnj@barc.gov.in [Homi Bhabha National Institute, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Singh, Param Jeet; Shastri, Aparna [Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2014-05-21T23:59:59.000Z

    The electronic absorption spectrum of diiodomethane in the 30?000–95?000 cm{sup ?1} region is investigated using synchrotron radiation; the spectrum in the 50?000–66?500 cm{sup ?1} region is reported for the first time. The absorption bands in the 30?000–50?000 cm{sup ?1} region are attributed to valence transitions, while the vacuum ultraviolet (VUV) spectrum (50?000–95?000 cm{sup ?1}) is dominated by several Rydberg series converging to the first four ionization potentials of CH{sub 2}I{sub 2} at 9.46, 9.76, 10.21, and 10.56 eV corresponding to the removal of an electron from the outermost 3b{sub 2}, 2b{sub 1}, 1a{sub 2}, and 4a{sub 1} non-bonding orbitals, respectively. Rydberg series of ns, np, and nd type converging to each of the four ionization potentials are assigned based on a quantum defect analysis. Time dependent density functional theory calculations of excited states support the analysis and help in interpretation of the Rydberg and valence nature of observed transitions. Density functional theory calculations of the neutral and ionic ground state geometries and vibrational frequencies are used to assign the observed vibronic structure. Vibronic features accompanying the Rydberg series are mainly due to excitation of the C-I symmetric stretch (?{sub 3}) and CH{sub 2} wag (?{sub 8}) modes, with smaller contributions from the C-H symmetric stretch (?{sub 1}). UV absorption bands are assigned to low lying valence states 1{sup 1}B{sub 2}, 1{sup 1}B{sub 1}, 2{sup 1}A{sub 1}, 3{sup 1}A{sub 1}, 2{sup 1}B{sub 1}, and 2{sup 1}B{sub 2} and the unusually high underlying intensity in parts of the VUV spectrum is attributed to valence states with high oscillator strength. This is the first report of a comprehensive Rydberg series and vibronic analysis of the VUV absorption spectrum of CH{sub 2}I{sub 2} in the 50?000–85?000 cm{sup ?1} region. The VUV absorption spectrum of CD{sub 2}I{sub 2} which serves to verify and consolidate spectral assignments is also reported here for the first time.

  13. Microsoft PowerPoint - NERC Reliability Standards and Mandatory Compliance Presentation to Hydro-Power Conference - June 2007.p

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand RetrievalsFinalModule8.pptStates A ComparisonMorgantown SiteNERC

  14. SIMULATION FRAMEWORK FOR REGIONAL GEOLOGIC CO{sub 2} STORAGE ALONG ARCHES PROVINCE OF MIDWESTERN UNITED STATES

    SciTech Connect (OSTI)

    Sminchak, Joel

    2012-09-30T23:59:59.000Z

    This report presents final technical results for the project Simulation Framework for Regional Geologic CO{sub 2} Storage Infrastructure along Arches Province of the Midwest United States. The Arches Simulation project was a three year effort designed to develop a simulation framework for regional geologic carbon dioxide (CO{sub 2}) storage infrastructure along the Arches Province through development of a geologic model and advanced reservoir simulations of large-scale CO{sub 2} storage. The project included five major technical tasks: (1) compilation of geologic, hydraulic and injection data on Mount Simon, (2) development of model framework and parameters, (3) preliminary variable density flow simulations, (4) multi-phase model runs of regional storage scenarios, and (5) implications for regional storage feasibility. The Arches Province is an informal region in northeastern Indiana, northern Kentucky, western Ohio, and southern Michigan where sedimentary rock formations form broad arch and platform structures. In the province, the Mount Simon sandstone is an appealing deep saline formation for CO{sub 2} storage because of the intersection of reservoir thickness and permeability. Many CO{sub 2} sources are located in proximity to the Arches Province, and the area is adjacent to coal fired power plants along the Ohio River Valley corridor. Geophysical well logs, rock samples, drilling logs, and geotechnical tests were evaluated for a 500,000 km{sup 2} study area centered on the Arches Province. Hydraulic parameters and historical operational information was also compiled from Mount Simon wastewater injection wells in the region. This information was integrated into a geocellular model that depicts the parameters and conditions in a numerical array. The geologic and hydraulic data were integrated into a three-dimensional grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO{sub 2} injection. Permeability data were corrected in locations where reservoir tests have been performed in Mount Simon injection wells. The geocellular model was used to develop a series of numerical simulations designed to support CO2 storage applications in the Arches Province. Variable density fluid flow simulations were initially run to evaluate model sensitivity to input parameters. Two dimensional, multiple-phase simulations were completed to evaluate issues related to arranging injection fields in the study area. A basin-scale, multiple-phase model was developed to evaluate large scale injection effects across the region. Finally, local scale simulations were also completed with more detailed depiction of the Eau Claire formation to investigate to the potential for upward migration of CO2. Overall, the technical work on the project concluded that injection large-scale injection may be achieved with proper field design, operation, siting, and monitoring. Records from Mount Simon injection wells were compiled, documenting more than 20 billion gallons of injection into the Mount Simon formation in the Arches Province over the past 40 years, equivalent to approximately 60 million metric tons CO2. The multi-state team effort was useful in delineating the geographic variability in the Mount Simon reservoir properties. Simulations better defined potential well fields, well field arrangement, CO2 pipeline distribution system, and operational parameters for large-scale injection in the Arches Province. Multiphase scoping level simulations suggest that injection fields with arrays of 9 to 50+ wells may be used to accommodate large injection volumes. Individual wells may need to be separated by 3 to 10 km. Injection fields may require spacing of 25 to 40 km to limit pressure and saturation front interference. Basin-scale multiple-phase simulations in STOMP reflect variability in the Mount Simon. While simulations suggest a total injection rate of 100 million metric tons per year (approximately to a 40% reduction of CO2 emissions from large point sources across the Arches Province) may be feasible,

  15. K{sub S} Lambda Photoproduction On The Neutron Within The Resonance Region

    SciTech Connect (OSTI)

    Taylor, Charles E. [Idaho State University, Pocatello, ID (United States); Cole, Philip L. [Idaho State University, Pocatello, ID (United States)

    2014-01-01T23:59:59.000Z

    We report some preliminary differential cross section results for the gammad --> K{sub S} Lambda(p) reaction using a circularly-polarized photon beam and an unpolarized LD{sub 2} target. The data was collected at the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. For this study the photon energy ranged from 1.3 to 2.53 GeV, which covers from the reaction threshold through the nucleon resonance regimes. The acceptance- and flux-corrected yields show peaks at the center-of mass energies W = 1.7 and W = 1.9 GeV. These first-time results will aid in unraveling the spectrum of non-strange excited baryons.

  16. Direct evidence of correlations between relaxor behavior and polar nano-regions in relaxor ferroelectrics: A case study of lead-free piezoelectrics Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}-x%BaTiO{sub 3}

    SciTech Connect (OSTI)

    Ge, Wenwei, E-mail: wenweige@gmail.com; Luo, Chengtao; Devreugd, Christopher P.; Li, Jiefang; Viehland, D. [Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States); Zhang, Qinhui; Luo, Haosu [Key Laboratory of Inorganic Functional Material and Device, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201800 (China)] [Key Laboratory of Inorganic Functional Material and Device, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201800 (China); Ren, Yang [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2013-12-09T23:59:59.000Z

    Diffuse scattering and relaxor behavior in Na{sub 0.5}Bi{sub 0.5}TiO{sub 3} (NBT) and NBT-5.6 at.?%BaTiO{sub 3} (NBT-5.6%BT) were investigated. X-ray diffraction revealed two types of diffuse scattering in NBT: (i) broad and (ii) asymmetric L-shaped. After modification with 5.6%BT, the broad diffuse scattering patterns became narrow, and the asymmetric L-shaped ones were replaced by symmetric ones. The symmetric diffuse scattering in NBT-5.6%BT disappeared with increasing dc electric field (E) for E???9.5?kV/cm where the frequency dispersion in the dielectric constant disappeared. These results demonstrate that the relaxor characteristics are directly correlated with the diffuse scattering and the presence polar nano-regions.

  17. Estimates of global, regional, and national annual CO{sub 2} emissions from fossil-fuel burning, hydraulic cement production, and gas flaring: 1950--1992

    SciTech Connect (OSTI)

    Boden, T.A.; Marland, G. [Oak Ridge National Lab., TN (United States); Andres, R.J. [University of Alaska, Fairbanks, AK (United States). Inst. of Northern Engineering

    1995-12-01T23:59:59.000Z

    This document describes the compilation, content, and format of the most comprehensive C0{sub 2}-emissions database currently available. The database includes global, regional, and national annual estimates of C0{sub 2} emissions resulting from fossil-fuel burning, cement manufacturing, and gas flaring in oil fields for 1950--92 as well as the energy production, consumption, and trade data used for these estimates. The methods of Marland and Rotty (1983) are used to calculate these emission estimates. For the first time, the methods and data used to calculate CO, emissions from gas flaring are presented. This C0{sub 2}-emissions database is useful for carbon-cycle research, provides estimates of the rate at which fossil-fuel combustion has released C0{sub 2} to the atmosphere, and offers baseline estimates for those countries compiling 1990 C0{sub 2}-emissions inventories.

  18. On an improved sub-regional water resources management representation for integration into earth system models

    SciTech Connect (OSTI)

    Voisin, Nathalie; Li, Hongyi; Ward, Duane L.; Huang, Maoyi; Wigmosta, Mark S.; Leung, Lai-Yung R.

    2013-09-30T23:59:59.000Z

    Human influence on the hydrologic cycle includes regulation and storage, consumptive use and overall redistribution of water resources in space and time. Representing these processes is essential for applications of earth system models in hydrologic and climate predictions, as well as impact studies at regional to global scales. Emerging large-scale research reservoir models use generic operating rules that are flexible for coupling with earth system models. Those generic operating rules have been successful in reproducing the overall regulated flow at large basin scales. This study investigates the uncertainties of the reservoir models from different implementations of the generic operating rules using the complex multi-objective Columbia River Regulation System in northwestern United States as an example to understand their effects on not only regulated flow but also reservoir storage and fraction of the demand that is met. Numerical experiments are designed to test new generic operating rules that combine storage and releases targets for multi-purpose reservoirs and to compare the use of reservoir usage priorities, withdrawals vs. consumptive demand, as well as natural vs. regulated mean flow for calibrating operating rules. Overall the best performing implementation is the use of the combined priorities (flood control storage targets and irrigation release targets) operating rules calibrated with mean annual natural flow and mean monthly withdrawals. The challenge of not accounting for groundwater withdrawals, or on the contrary, assuming that all remaining demand is met through groundwater extractions, is discussed.

  19. "Interconnection","NERC Regional Assesment Area","Net Internal Demand[1] -- Winter"

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells,1Stocksa. AppliancesTotal" "(Data from03.4B Winter net

  20. A SEARCH FOR INTERSTELLAR CARBON-CHAIN ALCOHOL HC{sub 4}OH IN STAR-FORMING REGION L1527 AND DARK CLOUD TMC-1

    SciTech Connect (OSTI)

    Araki, Mitsunori; Yamabe, Hiromichi; Koshikawa, Naohiro; Tsukiyama, Koichi [Department of Chemistry, Faculty of Science Division I, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku 162-8601, Tokyo (Japan); Takano, Shuro [Nobeyama Radio Observatory, 462-2 Nobeyama, Minamimaki, Minamisaku, Nagano 384-1305 (Japan); Nakane, Aya; Okabayashi, Toshiaki [Department of Chemistry, Faculty of Science, Shizuoka University, 836 Oya, Suruga-ku, Shizuoka 422-8529 (Japan); Kunimatsu, Arisa; Kuze, Nobuhiko, E-mail: araki@rs.kagu.tus.ac.jp [Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University, 7-1 Kioi-cho, Chiyoda-ku 102-8554, Tokyo (Japan)

    2012-01-10T23:59:59.000Z

    We report a sensitive search for the rotational transitions of the carbon-chain alcohol HC{sub 4}OH in the frequency range 21.2-46.7 GHz in the star-forming region L1527 and the dark cloud TMC-1. The motivation was laboratory detection of HC{sub 4}OH by microwave spectroscopy. Despite achieving rms noise levels of several millikelvin in the antenna temperature using the 45 m telescope at Nobeyama Radio Observatory, the detection was not successful, leading to 3{sigma} upper limits corresponding to the column densities of 2.0 Multiplication-Sign 10{sup 12} and 5.6 Multiplication-Sign 10{sup 12} cm{sup -2} in L1527 and TMC-1, respectively. These upper limits indicate that [HC{sub 4}OH]/[HC{sub 5}N] ratios are less than 0.3 and 0.1 in L1527 and TMC-1, respectively, where HC{sub 5}N is an HC{sub 4}-chain cyanide and HC{sub 4}OH is a hydroxide. These ratios suggest that the cyano carbon-chain molecule dominates the hydroxyl carbon-chain molecule in L1527 and TMC-1. This is contrary to the case of saturated compounds in hot cores, e.g., CH{sub 3}OH and CH{sub 3}CN, and can be a chemical feature of carbon-chain molecules in L1527 and TMC-1. In addition, the column densities of the 'unsubstituted' carbon-chain molecule C{sub 4}H and the sulfur-bearing molecules SO and HCS{sup +} were determined from detected lines in L1527.

  1. Solar ALMA: Observation-Based Simulations of the mm and sub-mm Emissions from Active Regions

    E-Print Network [OSTI]

    Fleishman, Gregory; Nita, Gelu

    2015-01-01T23:59:59.000Z

    We developed an efficient algorithm integrated in our 3D modeling tool, GX Simulator (Nita et al. 2015), allowing quick computation of the synthetic intensity and polarization maps of solar active regions (AR) in the ALMA spectral range. The algorithm analyzes the photospheric input (white light and magnetogram) to classify a given photospheric pixel to belong to a given photospheric structure. Then, a 1D chromospheric model (Fontenla et al. 2009) is added on top of each pixel, which forms a chromospheric model of the AR. Next step is computation of the mm and sub-mm emission produced from this chromosphere model. A huge advantage of this approach is that emission from any given AR can be synthesized very fast, on the order of a few minutes after the AR selection. Using the GX Simulator tool it is also possible to produce synthetic maps of the microwave (gyroresonance) and EUV emission from the same AR model and compare them with the ALMA synthetic maps and with the corresponding observed microwave and/or EUV...

  2. THE HDO/H{sub 2}O RATIO IN GAS IN THE INNER REGIONS OF A LOW-MASS PROTOSTAR

    SciTech Connect (OSTI)

    Joergensen, Jes K. [Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, Oester Voldgade 5-7, DK-1350 Copenhagen K. (Denmark); Van Dishoeck, Ewine F., E-mail: jes@snm.ku.d, E-mail: ewine@strw.leidenuniv.n [Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden (Netherlands)

    2010-12-20T23:59:59.000Z

    The HDO/H{sub 2}O abundance ratio is thought to be a key diagnostic for the evolution of water during the star and planet formation process and thus for its origin on Earth. We here present millimeter-wavelength high angular resolution observations of the deeply embedded protostar NGC 1333-IRAS4B from the Submillimeter Array targeting the 3{sub 12}-2{sub 21} transition of HDO at 225.6 GHz (E{sub u} = 170 K). We do not (or only very tentatively) detect the HDO line toward the central protostar, contrasting the previous prominent detection of a line from another water isotopologue, H{sup 18}{sub 2}O, with similar excitation properties using the IRAM Plateau de Bure Interferometer. The non-detection of the HDO line provides a direct, model-independent, upper limit to the HDO/H{sub 2}O abundance ratio of 6 x 10{sup -4} (3{sigma}) in the warm gas associated with the central protostar. This upper limit suggests that the HDO/H{sub 2}O abundance ratio is not significantly enhanced in the inner {approx}50 AU around the protostar relative to what is seen in comets and Earth's oceans and does not support previous suggestions of a generally enhanced HDO/H{sub 2}O ratio in these systems.

  3. Variable Density Flow Modeling for Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States

    SciTech Connect (OSTI)

    Joel Sminchak

    2011-09-30T23:59:59.000Z

    The Arches Province in the Midwestern U.S. has been identified as a major area for carbon dioxide (CO{sub 2}) storage applications because of the intersection of Mt. Simon sandstone reservoir thickness and permeability. To better understand large-scale CO{sub 2} storage infrastructure requirements in the Arches Province, variable density scoping level modeling was completed. Three main tasks were completed for the variable density modeling: Single-phase, variable density groundwater flow modeling; Scoping level multi-phase simulations; and Preliminary basin-scale multi-phase simulations. The variable density modeling task was successful in evaluating appropriate input data for the Arches Province numerical simulations. Data from the geocellular model developed earlier in the project were translated into preliminary numerical models. These models were calibrated to observed conditions in the Mt. Simon, suggesting a suitable geologic depiction of the system. The initial models were used to assess boundary conditions, calibrate to reservoir conditions, examine grid dimensions, evaluate upscaling items, and develop regional storage field scenarios. The task also provided practical information on items related to CO{sub 2} storage applications in the Arches Province such as pressure buildup estimates, well spacing limitations, and injection field arrangements. The Arches Simulation project is a three-year effort and part of the United States Department of Energy (U.S. DOE)/National Energy Technology Laboratory (NETL) program on innovative and advanced technologies and protocols for monitoring/verification/accounting (MVA), simulation, and risk assessment of CO{sub 2} sequestration in geologic formations. The overall objective of the project is to develop a simulation framework for regional geologic CO{sub 2} storage infrastructure along the Arches Province of the Midwestern U.S.

  4. SUBMILLIMETER H{sub 2}O MASER IN CIRCINUS GALAXY-A NEW PROBE FOR THE CIRCUMNUCLEAR REGION OF ACTIVE GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Hagiwara, Yoshiaki; Miyoshi, Makoto [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Doi, Akihiro [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuou-ku, Sagamihara, Kanagawa 252-5210 (Japan); Horiuchi, Shinji, E-mail: yoshiaki.hagiwara@nao.ac.jp [CSIRO Astronomy and Space Science, Canberra Deep Space Communications Complex, P.O. Box 1035, Tuggeranong, ACT 2901 (Australia)

    2013-05-10T23:59:59.000Z

    We present the first detection of extragalactic submillimeter H{sub 2}O maser in the 321 GHz transition toward the center of Circinus galaxy, the nearby Type 2 Seyfert using the Atacama Large Millimeter/Submillimeter Array. We find that Doppler features of the detected 321 GHz H{sub 2}O maser straddle the systemic velocity of the galaxy as seen in the spectrum of the known 22 GHz H{sub 2}O maser in the galaxy. By comparing the velocities of the maser features in both transitions, it can be deduced that the 321 GHz maser occurs in a region similar to that of the 22 GHz maser, where the sub-parsec-scale distribution of the 22 GHz maser was revealed by earlier very long baseline interferometry observations. The detected maser features remain unresolved at the synthesized beam of {approx}0.''66 ({approx}15 pc) and coincide with the 321 GHz continuum peak within small uncertainties. We also present a tentative detection of the highest velocity feature (redshifts up to {approx}635 km s{sup -1}) in the galaxy. If this high-velocity feature arises from a Keplerian rotating disk well established in this galaxy, it is located at a radius of {approx}0.018 pc ({approx}1.2 Multiplication-Sign 10{sup 5} Schwarzschild radii), which might probe molecular material closest to the central engine.

  5. Energy Efficiency in Western Utility Resource Plans: Impacts on Regional Resources Assessment and Support for WGA Policies

    E-Print Network [OSTI]

    Hopper, Nicole; Goldman, Charles; Schlegal, Jeff

    2006-01-01T23:59:59.000Z

    is equivalent to NERC’s definition of “Net Energy for Load”,their energy-efficiency savings projections, this definition

  6. NERC SERVICES ANNUAL REPORT

    E-Print Network [OSTI]

    Brierley, Andrew

    ) to manage. Research Ships, the aircraft facility (FAAM), and High Performance Computing are accountable

  7. Conceptual Model Summary Report Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States

    SciTech Connect (OSTI)

    None

    2011-06-30T23:59:59.000Z

    A conceptual model was developed for the Arches Province that integrates geologic and hydrologic information on the Eau Claire and Mt. Simon formations into a geocellular model. The conceptual model describes the geologic setting, stratigraphy, geologic structures, hydrologic features, and distribution of key hydraulic parameters. The conceptual model is focused on the Mt. Simon sandstone and Eau Claire formations. The geocellular model depicts the parameters and conditions in a numerical array that may be imported into the numerical simulations of carbon dioxide (CO{sub 2}) storage. Geophysical well logs, rock samples, drilling logs, geotechnical test results, and reservoir tests were evaluated for a 500,000 km{sup 2} study area centered on the Arches Province. The geologic and hydraulic data were integrated into a three-dimensional (3D) grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO{sub 2} injection. Permeability data were corrected in locations where reservoir tests have been performed in Mt. Simon injection wells. The final geocellular model covers an area of 600 km by 600 km centered on the Arches Province. The geocellular model includes a total of 24,500,000 cells representing estimated porosity and permeability distribution. CO{sub 2} injection scenarios were developed for on-site and regional injection fields at rates of 70 to 140 million metric tons per year.

  8. Measurement of astrophysical S factors and electron screening potentials for d(d, n){sup 3}He reaction In ZrD{sub 2}, TiD{sub 2}, D{sub 2}O, and CD{sub 2} targets in the ultralow energy region using plasma accelerators

    SciTech Connect (OSTI)

    Bystritsky, V. M. [Joint Institute for Nuclear Research (Russian Federation); Bystritskii, Vit. M. [University of California, Department of Physics and Astronomy (United States); Dudkin, G. N. [National Scientific Research Tomsk Polytechnical University (Russian Federation); Filipowicz, M. [University of Science and Technology, Faculty of Fuels and Energy, AGH (Poland); Gazi, S.; Huran, J. [Institute of Electrical Engineering SAS (Slovakia); Kobzev, A. P. [Joint Institute for Nuclear Research (Russian Federation); Mesyats, G. A. [Lebedev Physical Institute of the Russian Academy of Sciences (Russian Federation); Nechaev, B. A.; Padalko, V. N. [National Scientific Research Tomsk Polytechnical University (Russian Federation); Parzhitskii, S. S. [Joint Institute for Nuclear Research (Russian Federation); Pen'kov, F. M. [Institute of Nuclear Physics NNC (Kazakhstan); Philippov, A. V. [Joint Institute for Nuclear Research (Russian Federation); Kaminskii, V. L. [National Scientific Research Tomsk Polytechnical University (Russian Federation); Tuleushev, Yu. Zh. [Institute of Nuclear Physics NNC (Kazakhstan); Wozniak, J. [University of Science and Technology, Faculty of Physics and Applied Computer Sciences, AGH (Poland)

    2012-01-15T23:59:59.000Z

    The paper is devoted to study electron screening effect influence on the rate of d(d, n){sup 3}He reaction in the ultralow deuteron collision energy range in the deuterated polyethylene (CD{sub 2}), frozen heavy water (D{sub 2}O) and deuterated metals (ZrD{sub 2} and TiD{sub 2}). The ZrD{sub 2} and TiD{sub 2} targets were fabricated via magnetron sputtering of titanium and zirconium in gas (deuterium) environment. The experiments have been carried out using high-current plasma pulsed accelerator with forming of inverse Z pinch (HCEIRAS, Russia) and pulsed Hall plasma accelerator (NPI at TPU, Russia). The detection of neutrons with energy of 2.5MeV from dd reaction was done with plastic scintillation spectrometers. As a result of the experiments the energy dependences of astrophysical S factor for the dd reaction in the deuteron collision energy range of 2-7 keV and the values of the electron screening potential U{sub e} of interacting deuterons have been measured for the indicated above target: U{sub e}(CD{sub 2}) Less-Than-Or-Slanted-Equal-To 40 eV; U{sub e}(D{sub 2}O) Less-Than-Or-Slanted-Equal-To 26 eV; U{sub e}(ZrD{sub 2}) = 157 {+-} 43 eV; U{sub e}(TiD{sub 2}) = 125{+-}34 eV. The value of astrophysical S factor, corresponding to the deuteron collision energy equal to zero, in the experiments with D{sub 2}O target is found: S{sub b}(0) = 58.6 {+-} 3.6 keV b. The paper compares our results with other available published experimental and calculated data.

  9. Determination of the Azimuthal Asymmetry of Deuteron Photodisintegration in the Energy Region E{sub {gamma}} = 1.1 - 2.3 GeV

    SciTech Connect (OSTI)

    Nicholas Zachariou

    2012-05-20T23:59:59.000Z

    Deuteron photodisintegration is a benchmark process for the investigation of the role of quarks and gluons in nuclei. Existing theoretical models of this process describe the available cross sections with the same degree of success. Therefore, spin-dependent observables are crucial for a better understanding of the underlying dynamical mechanisms. However, data on the induced polarization (P{sub y}), along with the polarization transfers (C{sub x'} and C{sub z'} ), have been shown to be insensitive to differences between theoretical models. On the other hand, the beam-spin asymmetry {Sigma} is predicted to have a large sensitivity and is expected to help in identifying the energy at which the transition from the hadronic to the quark-gluon picture of the deuteron takes place. Here, the work done to determine the experimental values of the beam-spin asymmetry in deuteron photodisintegration for photon energies between 1.1 ? 2.3 GeV is presented. The data were taken with the CLAS at the Thomas Jefferson National Accelerator Facility during the g13 experiment. Photons with linear polarization of ~80% were produced using the coherent bremsstrahlung facility in Hall B. The work done by the author to calibrate a specific detector system, select deuteron photodisintegration events, study the degree of photon polarization, and finally determine the azimuthal asymmetry and any systematic uncertainties associate with it, is comprehensively explained. This work shows that the collected data provide the kinematic coverage and statistics to test the available QCD-based models. The results of this study show that the available theoretical models in their current state do not adequately predict the azimuthal asymmetry in the energy region 1.1 ? 2.3 GeV.

  10. Response of sulfate concentration and isotope composition in Icelandic rivers to the decline in global atmospheric SO{sub 2} emissions into the North Atlantic region

    SciTech Connect (OSTI)

    Sigurdur Reynir Gislason; Peter Torssander [University of Iceland, Reykjavik (Iceland). Institute of Earth Science

    2006-02-01T23:59:59.000Z

    This study presents the changes in dissolved sulfate concentration and isotope composition of Icelandic river waters between the peak of SO{sub 2} emissions in the United States and Europe and the present. Chloride concentration in Icelandic rivers has not changed much since 1972. The overall average change from 1972-1973 to 1996-2004 was -3%, indicating insignificant sea-salt contribution changes. More than 99% of the river-dissolved sulfur was in the form of sulfate. There are three main sources for dissolved sulfate in the rivers: rocks, sea-salts, and anthropogenic. Total dissolved sulfate, {sub td}SO{sub 4}{sup 2-}, and non-sea-salt sulfate, {sub nss}SO{sub 4}{sup 2-}, decreased in all of the rivers from the early 1970s to 1996-2004. The percentage decrease varies from 13% to 65%. The decrease is smallest in rivers were there is considerable rock-derived dissolved SO{sub 4}{sup 2-}. The overall average decrease was 39% for {sub td}SO{sub 4}{sup 2-} and 46% for {sub nss}SO{sub 4}{sup 2-}. The anthropogenic sulfate fraction has declined making most of the river waters {delta}{sup 34}S values of sulfate higher through time. The overall decline in river sulfate and increase in {delta}{sup 34}S, while SO{sub 2} emissions from Iceland has been increasing, demonstrates the response of river chemistry in the remote North Atlantic to the decline in man-made emissions of SO{sub 2} in North America and Europe. 43 refs., 8 figs., 1 tab.

  11. Phase equilibria in the quasi-ternary system Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} and physical properties of (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} single crystals

    SciTech Connect (OSTI)

    Ivashchenko, I.A., E-mail: inna.ivashchenko@mail.ru [Department of Inorganic and Physical Chemistry, Eastern European National University, Voli Ave 13, Lutsk 43025 (Ukraine); Danyliuk, I.V.; Olekseyuk, I.D. [Department of Inorganic and Physical Chemistry, Eastern European National University, Voli Ave 13, Lutsk 43025 (Ukraine); Halyan, V.V. [Department of General Physics, Eastern European National University, Voli Ave 13, Lutsk 43025 (Ukraine)

    2014-02-15T23:59:59.000Z

    The quasi-ternary system Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} was investigated by differential thermal, X-ray phase, X-ray structure, microstructure analysis and microhardness measurements. Five quasi-binary phase diagrams, six polythermal sections, isothermal section at 820 K and the liquidus surface projection were constructed. The character and temperature of the invariant processes were determined. The specific resistance of the single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} was measured, 7.5×10{sup 5} and 3.15×10{sup 5} ? m, respectively, optical absorption spectra in the 600–1050 nm range were recorded at room temperature, and the band gap energy was estimated which is 1.95±0. 01 eV for both samples. - Graphical abstract: The article reports for the first time the investigated liquidus surface projection of the Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system and isothermal section at 820 K of the system. Five phase diagrams, six polythermal sections, isothermal section at 820 K and the liquidus surface projection were built at the first time. The existence of the large region of the solid solutions based on AgIn{sub 5}Se{sub 8}, Ga{sub 2}Se{sub 3} and AgGa{sub 1?x}In{sub x}Se{sub 2} was investigated. The existence of two ternary phases was established in the Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system. Two single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} were grown and some of optical properties of them were studied at first time. Display Omitted - Highlights: • Liquidus surface projection was built for Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system. • Solid solution ranges of AgIn{sub 5}Se{sub 8}, Ga{sub 2}Se{sub 3} and AgGa{sub 1?x}In{sub x}Se{sub 2} were investigated. • Two single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} were grown. • Some optical properties of these single crystals were studied.

  12. Tunneling study of epitaxial YBa sub 2 Cu sub 3 O sub x superconducting films

    SciTech Connect (OSTI)

    Boguslavsky, Y.M.; Rudenko, E.M.; Mukhortov, V.M. (Inst. of Metal Physics, Ukrainian Academy of Sciences, 36 Vernadsky str. 252142, Kiev-142 (SU))

    1991-03-01T23:59:59.000Z

    This paper presents planar and edge-type tunnel junctions YBa{sub 2}Cu{sub 3}O{sub x}-metal (Pb,Pt,In) based on epitaxial Y-Ba-Cu-O films. Features of conductance characteristics of these junctions, mainly conductance zero bias anomalies, have been considered. We have observed the difference between the R{sub d}(V) dependences for two types of the contacts at low bias voltages V {approx lt}5 mV. This difference probably linked with an anisotropy of the states density N ({epsilon}) in near-contact region of YBa{sub 2}Cu{sub 3}O{sub x}. Existence of the correlation in the temperature dependences of the states density of YBa{sub 2}Cu{sub 3}O{sub x} along the Cu-O planes and perpendicularly to them have been observed.

  13. Impacts Assessment of Plug-in Hybrid Vehicles on Electric Utilities and Regional US Power Grids: Part 1: Technical Analysis

    SciTech Connect (OSTI)

    Kintner-Meyer, Michael CW; Schneider, Kevin P.; Pratt, Robert G.

    2007-01-31T23:59:59.000Z

    This initial paper estimates the regional percentages of the energy requirements for the U.S. light duty vehicle stock that could be supported by the existing grid, based on 12 NERC regions. This paper also discusses the impact of overall emissions of criteria gases and greenhouse gases as a result of shifting emission from millions of tailpipes to a relatively few power plants. The paper concludes with an outlook of the technology requirements necessary to manage the additional and potentially sizable new load to maintain grid reliability.

  14. Evidence for tt?? Production and Measurement of (?<sub> tt?sub>)?/(?tt?>)

    SciTech Connect (OSTI)

    Aaltonen, T [Helsinki Inst. of Phys.; Alvarez Gonzalez, B [Oviedo U.; Cantabria Inst. of Phys.; Amerio, S [INFN, Padua; Amidei, D [Michigan U.; Anastassov, A [Northwestern U.; Annovi, A [Frascati; Antos, J [Comenius U.; Apollinari, G [Fermilab; Appel, J A [Fermilab; Apresyan, A [Purdue U.; Arisawa, T [Waseda U.; Dubna, JINR

    2011-08-31T23:59:59.000Z

    Using data corresponding to 6.0 fb-1 of pp? collisions at ?s = 1.96 TeV collected by the CDF II detector, we present a cross section measurement of top-quark pair production with an additional radiated photon, tt??. The events are selected by looking for a lepton (ell), a photon (?), significant transverse momentum imbalance (E<sub>T>), large total transverse energy, and three or more jets, with at least one identified as containing a b quark (b). The tt?? sample requires the photon to have 10 GeV or more of transverse energy, and to be in the central region. Using an event selection optimized for the tt?? candidate sample we measure the production cross section of tt? (?<sub>tt?>), and the ratio of cross sections of the two samples. Control samples in the dilepton+photon and lepton+photon+E<sub>T>, channels are constructed to aid in decay product identification and background measurements. We observe 30 tt?? candidate events compared to the standard model expectation of 26.9 ± 3.4 events. We measure the tt?? cross section (?<sub>tt?>) to be 0.18 ± 0.08 pb, and the ratio of ?<sub>tt?>? to ?<sub>tt?> to be 0.024 ± 0.009. Assuming no tt?? production, we observe a probability of 0.0015 of the background events alone producing 30 events or more, corresponding to 3.0 standard deviations.

  15. CO{sub 2} Sequestration Capacity and Associated Aspects of the Most Promising Geologic Formations in the Rocky Mountain Region: Local-Scale Analyses

    SciTech Connect (OSTI)

    Laes, Denise; Eisinger, Chris; Morgan, Craig; Rauzi, Steve; Scholle, Dana; Scott, Phyllis; Lee, Si-Yong; Zaluski, Wade; Esser, Richard; Matthews, Vince; McPherson, Brian

    2013-07-30T23:59:59.000Z

    The purpose of this report is to provide a summary of individual local-­?scale CCS site characterization studies conducted in Colorado, New Mexico and Utah. These site-­? specific characterization analyses were performed as part of the “Characterization of Most Promising Sequestration Formations in the Rocky Mountain Region” (RMCCS) project. The primary objective of these local-­?scale analyses is to provide a basis for regional-­?scale characterization efforts within each state. Specifically, limits on time and funding will typically inhibit CCS projects from conducting high-­? resolution characterization of a state-­?sized region, but smaller (< 10,000 km{sup 2}) site analyses are usually possible, and such can provide insight regarding limiting factors for the regional-­?scale geology. For the RMCCS project, the outcomes of these local-­?scale studies provide a starting point for future local-­?scale site characterization efforts in the Rocky Mountain region.

  16. Hydrides of CeNi/sub 5/, MmNi/sub 5/, Ca/sub 0/ /sub 2/(Ce/sub 0/ /sub 65/Mm/sub 0/ /sub 35/)/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Ce/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Mm/sub 0/ /sub 8/Ni/sub 5/, and mixed CeNi/sub 5//MmNi/sub 5/

    SciTech Connect (OSTI)

    Lakner, J.F.; Chow, T.S.

    1982-09-01T23:59:59.000Z

    Six intermetallic alloys (CeNi/sub 5/, MmNi/sub 5/, Ca/sub 0/ /sub 2/(Ce/sub 0/ /sub 65/Mm/sub 0/ /sub 35/)/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Ce/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Mm/sub 0/ /sub 8/Ni/sub 5/, and a mixed alloy, CeNi/sub 5//MmNi/sub 5/) were investigated with respect to their suitability to provide high hydrogen capacity and their potential for use in providing substantial hydrogen pressure at both low and high temperatures. A second phase of our investigation dealt with ball-milling and hydriding and dehydriding cycles to produce fine particles for use in hydride powder transfer studies. A summary of several Van't Hoff plots is also included for hydride-forming alloys.

  17. Interactions of Ba{sub 2}YCu{sub 3}O{sub 6+y} with the Gd{sub 3}NbO{sub 7} buffer layer in coated conductors

    SciTech Connect (OSTI)

    Wong-Ng, W., E-mail: Winnie.wong-ng@nist.go [Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Yang, Z. [Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Kaduk, J.A. [INEOS Technology, Naperville, IL 60566-7011 (United States); Cook, L.P. [Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Paranthaman, M. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2010-03-15T23:59:59.000Z

    A systematic study of the chemical interaction of Ba{sub 2}YCu{sub 3}O{sub 6+y} and Gd{sub 3}NbO{sub 7} was conducted under two processing conditions: purified air (21% p{sub o{sub 2}}), and 100 Pa p{sub o{sub 2}} (0.1% p{sub o{sub 2}}). Phases present along the pseudo-binary join Ba{sub 2}YCu{sub 3}O{sub 6z} and Gd{sub 3}NbO{sub 7} were found to be in two five-phase volumes within the BaO-1/2 Y{sub 2}O{sub 3}-1/2 Gd{sub 2}O{sub 3}-Nb{sub 2}O{sub 5}-CuO{sub y} system. Three common phases that are present in all samples are (Y,Gd){sub 2}Cu{sub 2}O{sub 5}, Ba(Y,Gd){sub 2}CuO{sub 5} and Cu{sub 2}O or CuO (depending on the processing conditions). The assemblies of phases can be categorized in three regions, with Ba{sub 2}YCu{sub 3}O{sub 6+y}: Gd{sub 3}NbO{sub 7} ratios of (I)<5.5:4.5; (II)=5.5:4.5; and (III)>5.5:4.5. The lowest melting temperature of the system was determined to be {approx}938 deg. C in air, and 850 deg. C at 100 Pa p{sub o{sub 2}}. Structure determinations of two selected phases, Ba{sub 2}(Gd{sub x}Y{sub 1-x})NbO{sub 6} (Fm3-barm, No. 225), and (Gd{sub x}Y{sub 3-x})NbO{sub 7} (C222{sub 1}, No. 20 and Ccmm, No. 63), were completed using the X-ray Rietveld refinement technique. Reference X-ray powder diffraction patterns for selected phases of Ba{sub 2}(Gd{sub x}Y{sub 1-x})NbO{sub 6} (x=0.2, 0.4, 0.6, and 0.8) and (Gd{sub x}Y{sub 3-x})NbO{sub 7} (x=0.6, 1.2, 1.8, 2.4 and 3) have been prepared for inclusion in the Powder Diffraction File (PDF). - Graphical abstract: Crystal structure for (Gd{sub x}Y{sub 3-x})NbO{sub 7} showing the partial layered feature. The alternate stacking of distorted NbO{sub 6} octahedra and (Gd,Y)O{sub 7} polyhedra are illustrated. The (Gd,Y)O{sub 8} polyhedra are omitted for clarity.

  18. Measurement of the Target-Normal Single-Spin Asymmetry A{sub y}{sup n} in the Deep Inelastic Region from the Reaction {sup 3}He{up_arrow}(e,e')

    SciTech Connect (OSTI)

    Katich, Joseph [William and Mary College

    2011-01-01T23:59:59.000Z

    A first measurement of the inclusive target single-spin asymmetry, A{sup n}{sub y}, has been performed in deep-inelastic scattering of electrons from a {sup 3}He target polarized normal to the electron scattering plane. This asymmetry is void of contributions at the Born level, and thus is a direct observable for two-photon physics. The experiment was performed in Hall A at Thomas Jefferson National Accelerator Facility from October 2008 through early February 2009. The measurement is the first from a polarized neutron target. The final overall precision is several times better than previously existing SLAC proton data, and significantly extends the kinematic range over which the asymmetry has been measured. The asymmetry was measured at five kinematic points in the deep inelastic scattering region covering Q{sup 2} = 1 - 3 GeV{sup 2} and x{sub B} = 0.16 to 0.41. The asymmetry varied from 0.006 to 0.071 with astatistical precision at the 10{sup -2} level.

  19. The potential impacts of a competitive wholesale market in the midwest: A preliminary examination of centralized dispatch

    E-Print Network [OSTI]

    Lesieutre, Bernard C.; Bartholomew, Emily; Eto, Joseph H.; Hale, Douglas; Luong, Thanh

    2004-01-01T23:59:59.000Z

    states and three NERC reliability regions. MISO is the firstmulti-reliability-region operation. Membership in the MISO-

  20. Liquid-phase oxidation of anthracene by hydrogen peroxide in the presence of vanadium oxide bronzes Cu{sub x}V{sub 2}O{sub 5}

    SciTech Connect (OSTI)

    Men`shikov, S.Yu.; Vurasko, A.V.; Petrov, L.A.; Volkov, V.L.; Novoselova, A.A. [Inst. of Chemistry, Sverdlovsk (Russian Federation)

    1992-12-31T23:59:59.000Z

    Vanadium oxide bronzes of the general formula Cu{sub x}V{sub 2}O{sub 5}, where 0 sub 2}O{sub 2}. The anthracene conversion and the selectivity with respect to anthraquinone are maximum within the region of {Beta}- and {Xi}-phases respectively close to the compositions Cu{sub 0.6} V{sub 2}O{sub 5} and Cu{sub 0.95}V{sub 2}O{sub 5}. This is connected with change in the electronic structure of the catalyst, which is a function of the copper content. 11 refs., 1 tab.

  1. Synthesis and characterization of the ((CO)/sub 4/MoS/sub 2/MS/sub 2/)/sup 2 -/ and ((CO)/sub 4/MoS/sub 2/MS/sub 2/Mo(CO)/sub 4/)/sup 2 -/ ions (M = Mo, W): species containing group VI (6) metals in widely separated formal oxidation states

    SciTech Connect (OSTI)

    Rosenhein, L.D.; McDonald, J.W.

    1987-10-07T23:59:59.000Z

    Dinuclear and trinuclear sulfide-bridged complexes of the types (Et/sub 4/N)/sub 2/(MS/sub 4/(Mo(CO)/sub 4/)) and (Et/sub 4/N)/sub 2/(MS/sub 4/(Mo(CO)/sub 4/)/sub 2/) were prepared by the reaction of one or two equivalents of Mo(CO)/sub 4/(C/sub 7/H/sub 8/) (C/sub 7/H/sub 8/ = norbornadiene) with (Et/sub 4/N)/sub 2/(MS/sub 4/) (M = Mo, W) in methyl alcohol. Elemental analyses were consistent with the proposed formulae. Infrared spectra of all four compounds contain strong bands in the carbonyl region and low-energy bands characteristic of terminal and bridging M-S vibrations in linear, polynuclear, and sulfido-bridged species. Electrochemical experimental results support the hypothesis that the di- and trinuclear species contain both M(IV) (M = Mo, W) and Mo(0) oxidation states in the same complex. 33 references, 2 tables.

  2. Phase evolution studies in CaZrTi{sub 2}O{sub 7}?RE{sub 2}Ti{sub 2}O{sub 7} (RE?=?Nd{sup 3+}, Sm{sup 3+}) system: Futuristic ceramic host matrices for nuclear waste immobilization

    SciTech Connect (OSTI)

    Jafar, M., E-mail: sachary@barc.gov.in; Achary, S. N., E-mail: sachary@barc.gov.in; Tyagi, A. K., E-mail: sachary@barc.gov.in [Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)

    2014-04-24T23:59:59.000Z

    Series of compositions with general stoichiometry as Ca{sub 1?x}Zr{sub 1?x}RE{sub 2x}Ti{sub 2}O{sub 7} (RE?=?Nd{sup 3+}, Sm{sup 3+}) were prepared by solid state reaction and characterized by powder x-ray diffraction technique to unravel the phase fields in the title systems. The phase fields in CaZrTi{sub 2}O{sub 7?}Nd{sub 2}Ti{sub 2}O{sub 7} and CaZrTi{sub 2}O{sub 7?}Sm{sub 2}Ti{sub 2}O{sub 7} systems differed significantly at the rareearth rich regions. The common phase fields like zirconolite-2M, zirconolite-4M, cubic perovskite are observed at the zirconolite rich regions of both systems. Depending on the structure of RE{sub 2}Ti{sub 2}O{sub 7} phase, the cubic pyrochlore or monoclinic RE{sub 2}Ti{sub 2}O{sub 7} phases are observed in the studied system. The observed phase fields in these two systems indicate ionic radius of the rare-earth ion has a dominating role in the phase relations. Further details of the phases and their homogeneity are explained in the text of the manuscript.

  3. Behavior of the magnetocaloric effect and critical exponents in La{sub 0.67}Sr{sub 0.33}Mn{sub 1?x}V{sub x}O{sub 3} manganite oxide

    SciTech Connect (OSTI)

    Mnefgui, S., E-mail: safa_fsm@yahoo.fr [Laboratoire de la Matière Condensée et de la Nanoscience, Département de Physique, Faculté des Sciences de Monastir, 5019 Tunisia (Tunisia); Zaidi, N.; Dhahri, A. [Laboratoire de la Matière Condensée et de la Nanoscience, Département de Physique, Faculté des Sciences de Monastir, 5019 Tunisia (Tunisia); Hlil, E.K. [Institut Néel, CNRS-Université J. Fourier, B.P. 166, 38042 Grenoble (France); Dhahri, J. [Laboratoire de la Matière Condensée et de la Nanoscience, Département de Physique, Faculté des Sciences de Monastir, 5019 Tunisia (Tunisia)

    2014-07-01T23:59:59.000Z

    We have investigated the magnetocaloric effect along with magnetic phase transition and critical exponent analysis in mixed manganite La{sub 0.67}Sr{sub 0.33}Mn{sub 1?x}V{sub x}O{sub 3} (0?x?0.15). To determine the nature of the paramagnetic to ferromagnetic phase transition, found to be of second-order, we performed a critical exponents study by dc-magnetization M(H,T) measurements around the Curie temperature T{sub C}. Modified Arrott plot method has been adopted to study the critical behavior of the compounds at their transition region, the values of critical exponents ?, ? and ? are close to those expected for three-dimensional Heisenberg class with short-range interaction. A large magnetic entropy change |?S{sub M}| deduced from isothermal magnetization curves, has been observed in our samples with a peak centered on their respective T{sub C}. With increase in vanadium content, the temperature corresponding to the maximum entropy change as well as the magnetic transition temperature gradually shifts to low temperatures. The field dependence of the magnetic entropy change is also analyzed, which shows the power law dependence namely, ?S{sub M}?H{sup n}. Relative cooling power increases from 205 J/kg for x=0.00 to 258 J/Kg for x=0.15 making these materials a promising candidates for magnetic refrigeration near room temperature. - Graphical abstract: Scaling plot below and above T{sub C} using the ? and ? exponents determined from the Arrot plot method of La{sub 0.67}Sr{sub 0.33}Mn{sub 1?x}V{sub x}O{sub 3} for x=0.15. - Highlights: • The paramagnetic to ferromagnetic phase transition of La{sub 0.67}Sr{sub 0.33}Mn{sub 1?x}V{sub x}O{sub 3} (0?x?0.15) is found to be of second-order. • The field dependence of the magnetic entropy shows the power law dependence namely, ?S{sub M}?H{sup n}. • Moderate values of ??S{sub M}{sup max} and RCP make the La{sub 0.67}Sr{sub 0.33}Mn{sub 1?x}V{sub x}O{sub 3} compounds potential candidates for magnetic refrigeration applications.

  4. A novel red phosphor Ca{sub 12}Al{sub 14}O{sub 32}Cl{sub 2}:Eu{sup 3+} for near UV white light-emitting diodes

    SciTech Connect (OSTI)

    Yang, Zhigang; Zhao, Zhengyan; Shi, Yurong; Wang, Yuhua, E-mail: wyh@lzu.edu.cn

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • Novel red phosphor Ca{sub 12}Al{sub 14}O{sub 32}Cl{sub 2}:Eu{sup 3+} was prepared by solid-state reaction. • Excitation spectra suggested an obvious absorption in near-ultraviolet region. • Under 392 nm excitation, the phosphors exhibited a red emission at 614 nm. • Ca{sub 12}Al{sub 14}O{sub 32}Cl{sub 2}:Eu{sup 3+} could be potentially applied in near UV white LEDs. - Abstract: A novel red phosphor Ca{sub 12}Al{sub 14}O{sub 32}Cl{sub 2}:Eu{sup 3+} was synthesized using a solid-state reaction method, and its luminescence characteristics and charge compensators effect (Li{sup +}, Na{sup +}, K{sup +}) were investigated. The excitation spectra showed a obvious absorption in near-ultraviolet region. Under 392 nm excitation, the phosphors exhibited an intense red emission at 614 nm. The Commission Internationale de l’Eclairage (CIE) chromaticity coordinates and quantum efficiency (QE) were (0.65, 0.35) and 62.3%, respectively. The good color saturation, high quantum efficiency and small thermal-quenching properties indicate that Ca{sub 12}Al{sub 14}O{sub 32}Cl{sub 2}:Eu{sup 3+} could be potentially applied in near UV white light-emitting diodes.

  5. Structural study of Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} and optical spectroscopy of the Eu{sup 3+} dopant ion

    SciTech Connect (OSTI)

    Piccinelli, Fabio, E-mail: fabio.piccinelli@univr.it; Pedroni, Marco; Cagliero, Stefano; Speghini, Adolfo; Bettinelli, Marco

    2014-04-01T23:59:59.000Z

    The new rare earth-based germanate compound Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} (orthorhombic (Pnma) crystal structure), has been characterized and investigated for the first time, using synchrotron powder X-ray diffraction. From Rietveld refinement calculations on the collected powder pattern we observe an inhomogeneous distribution of the two available cationic sites by Gd{sup 3+} and Ca{sup 2+} ions. In particular, the former prefers the occupation (67.5%) of the site with 8-fold coordination. In addition, we observed a not negligible degree of distortion of the Ge{sub 2}O{sub 7}{sup 6?} unit. Finally, luminescence spectra and decay curves of Eu{sup 3+} doped Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} were measured and analysed taking into account the structural features of the host. The results reveal that this material shows strong red luminescence upon excitation in the region where blue LEDs emit (470 nm). - Graphical abstract: The structural study on Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} exploiting synchrotron X-ray diffraction, allows us to determine the detailed geometry of the metal coordination polyhedra, which is closely related to the emission luminescence spectroscopy of the Eu{sup 3+} dopant ion introduced as impurity in this host. - Highlights: • The crystal structure of the Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} was determined. • Gd{sup 3+} ion is distributed on two crystal sites with different occupation. • A structural study focused on the metal coordination polyhedra was performed. • Two emitting sites are detected for Eu{sup 3+} dopant ion in Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9}. • Strong red luminescence by excitation in the region where blue LEDs emit was found.

  6. Indonesia-Sub National Planning for Climate Change (cities, states...

    Open Energy Info (EERE)

    References "Asia Regional" Retrieved from "http:en.openei.orgwindex.php?titleIndonesia-SubNationalPlanningforClimateChange(cities,states,districts)&oldid700428...

  7. Cambodia-Sub National Planning for Climate Change (cities, states...

    Open Energy Info (EERE)

    References "Asia Regional" Retrieved from "http:en.openei.orgwindex.php?titleCambodia-SubNationalPlanningforClimateChange(cities,states,districts)&oldid700434...

  8. Effects of thermal annealing on the microstructure of sputtered Al{sub 2}O{sub 3} coatings

    SciTech Connect (OSTI)

    Edlmayr, V.; Harzer, T. P.; Hoffmann, R.; Kiener, D.; Scheu, C.; Mitterer, C. [Department of Physical Metallurgy and Materials Testing, University of Leoben, A-8700 Leoben (Austria); Department of Chemistry, Ludwig-Maximilians-University of Munich, D-81377 Munich (Germany); Department of Physical Metallurgy and Materials Testing, University of Leoben, A-8700 Leoben (Austria)

    2011-07-15T23:59:59.000Z

    The morphology and microstructure of Al{sub 2}O{sub 3} thin films deposited by pulsed direct current magnetron sputtering were studied in the as-grown state and after vacuum annealing at 1000 deg. C for 12 h using transmission electron microscopy. For the coating deposited under low ion bombardment conditions, the film consists of small {gamma}- and/or {delta}-Al{sub 2}O{sub 3} grains embedded in an amorphous matrix. The grain size at the region close to the interface to the substrate was much larger than that of the remaining layer. Growth of the {gamma}-Al{sub 2}O{sub 3} phase is promoted during annealing but no transformation to {alpha}-Al{sub 2}O{sub 3} was detected. For high-energetic growth conditions, clear evidence for {gamma}-Al{sub 2}O{sub 3} formation was found in the upper part of the coating with grain size much larger than for low-energetic growth, but the film was predominately amorphous at the interface region. Annealing resulted in the transformation of {gamma}-Al{sub 2}O{sub 3} to {alpha}-Al{sub 2}O{sub 3}, while the mainly amorphous part crystallized to {gamma}-Al{sub 2}O{sub 3}.

  9. K{sub 2}Fe{sub 2}B{sub 2}O{sub 7}: A transparent nonlinear optical crystal with frustrated magnetism

    SciTech Connect (OSTI)

    Wang Yonggang [Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Li, R.K., E-mail: rkli@mail.ipc.ac.c [Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2010-06-15T23:59:59.000Z

    A new noncentrosymmetric ferroborate crystal, K{sub 2}Fe{sub 2}B{sub 2}O{sub 7}, has been grown from high temperature melt. Structure solution from single crystal X-ray diffraction shows that the title compound crystallizes in a trigonal space group P321 with cell dimensions of a=8.7475(12) A and c=8.5124(17) A. In the structure, FeO{sub 4} tetrahedron shares its three basal oxygen atoms with BO{sub 3} triangles forming a two-dimensional layer in the ab plane and the layers are connected by the apical Fe-O bonds along the c direction. The crystal is transparent in the visible and near infrared region from 500 to 2000 nm with three pronounced absorption bands ascribed to d-d transitions of tetrahedrally coordinated Fe{sup 3+} ions. Though, structurally analog to K{sub 2}Al{sub 2}B{sub 2}O{sub 7}, the further twisting of the BO{sub 3} groups between adjacent layers reduces its optical nonlinearity to a second-harmonic generation intensity of about 0.4 times that of KDP. Spin-glass behavior is observed at 20 K which is probably due to geometrically magnetic frustration of the triangular Fe net in the ab plane. - Graphical abstract: Single crystal of a new ferroborate K{sub 2}Fe{sub 2}B{sub 2}O{sub 7}, space group P321, a=8.7475(3) A, c=8.5124(3) A, was obtained and characterized. It exhibits considerable SHG efficiency and frustrated magnetism originated from the triangular Fe net in the ab plane.

  10. X-ray and neutron powder diffraction studies of Ba(Nd{sub x}Y{sub 2-x})CuO{sub 5}

    SciTech Connect (OSTI)

    Liu, G. [Ceramics Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States); Huang, Q. [NIST Center for Neutron Research, Naperville, IL 60563 (United States); Kaduk, J.A. [INEOS Technologies, Naperville, IL 60563 (United States); Yang, Z. [Yunnan Normal University, Kunming 650092 (China); Lucas, C. [Chemistry and Biochemistry Department, University of Maryland, College Park, MD 20742 (United States); Wong-Ng, W. [Ceramics Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States)], E-mail: Winnie.wong-ng@nist.gov

    2008-12-15T23:59:59.000Z

    Ba(R,R'){sub 2}CuO{sub 5} (R,R'=lanthanides and Y) plays an important role as a flux-pinning agent in enhancing the superconducting properties of the Ba{sub 2}(R,R')Cu{sub 3}O{sub 6+x} (R,R'=lanthanides and Y) coated conductors. Using X-ray diffraction and neutron diffraction, we found that the Ba(Nd{sub x}Y{sub 2-x})CuO{sub 5} solid solution adopts two structure types. In the Nd-rich region (1.8{<=}x{<=}2.0), the materials are of brown color (commonly referred to as the 'brown phase'), and the structure is tetragonal with space group I4/mbm (no. 127). In the Y-rich region (0.0{<=}x{<=}1.4), the materials are green (commonly referred to as the 'green phase') and the structure is orthorhombic with space group Pnma (no. 62). A two-phase region (1.4sub x}Y{sub 2-x})CuO{sub 5} (isostructural to BaY{sub 2}CuO{sub 5}), are discussed in this paper. - Graphical abstract: Perspective view of the 'green phase' Ba(Nd{sub x}Y{sub 2-x})CuO{sub 5} structure along the b-axis, showing the isolated square pyramids of [CuO{sub 5}] and the trigonal prisms, RO{sub 7}, around the lanthanide sites.

  11. Life-Cycle Water Impacts of U.S. Transportation Fuels

    E-Print Network [OSTI]

    Scown, Corinne Donahue

    2010-01-01T23:59:59.000Z

    Cycle Water Consumption for WECC NERC Region ElectricityCycle Water Withdrawals for WECC NERC Region ElectricityTRE TS&D USDA USGS VC W WECC WSI International Organization

  12. Band gap engineering of In{sub 2}O{sub 3} by alloying with Tl{sub 2}O{sub 3}

    SciTech Connect (OSTI)

    Scanlon, David O., E-mail: d.scanlon@ucl.ac.uk [Kathleen Lonsdale Materials Chemistry, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Regoutz, Anna; Egdell, Russell G. [Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR (United Kingdom)] [Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR (United Kingdom); Morgan, David J. [Cardiff Catalysis Institute (CCI), School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom)] [Cardiff Catalysis Institute (CCI), School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom); Watson, Graeme W. [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland)] [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland)

    2013-12-23T23:59:59.000Z

    Efficient modulation of the bandgap of In{sub 2}O{sub 3} will open up a route to improved electronic properties. We demonstrate using ab initio calculations that Tl incorporation into In{sub 2}O{sub 3} reduces the band gap and confirm that narrowing of the gap is observed by X-ray photoemission spectroscopy on ceramic surfaces. Incorporation of Tl does not break the symmetry of the allowed optical transitions, meaning that the doped thin films should retain optical transparency in the visible region, in combination with a lowering of the conduction band effective mass. We propose that Tl-doping may be an efficient way to increase the dopability and carrier mobility of In{sub 2}O{sub 3}.

  13. Colossal anisotropic resistivity and oriented magnetic domains in strained La{sub 0.325}Pr{sub 0.3}Ca{sub 0.375}MnO{sub 3} films

    SciTech Connect (OSTI)

    Jiang, Tao; Yang, Shengwei; Liu, Yukuai; Zhao, Wenbo; Feng, Lei; Li, Xiaoguang, E-mail: lixg@ustc.edu.cn [Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, University of Science and Technology of China, Hefei 230026 (China); Zhou, Haibiao; Lu, Qingyou [Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, University of Science and Technology of China, Hefei 230026 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei 230031 (China); Hou, Yubin [High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei 230031 (China)

    2014-05-19T23:59:59.000Z

    Magnetic and resistive anisotropies have been studied for the La{sub 0.325}Pr{sub 0.3}Ca{sub 0.375}MnO{sub 3} films with different thicknesses grown on low symmetric (011)-oriented (LaAlO{sub 3}){sub 0.3}(SrAl{sub 0.5}Ta{sub 0.5}O{sub 3}){sub 0.7} substrates. In the magnetic and electronic phase separation region, a colossal anisotropic resistivity (AR) of ?10{sup 5}% and an anomalous large anisotropic magnetoresistance can be observed for 30 nm film. However, for 120 nm film, the maximum AR decreases significantly (?2?×?10{sup 3}%) due to strain relaxation. The colossal AR is strongly associated with the oriented formation of magnetic domains, and the features of the strain effects are believed to be useful for the design of artificial materials and devices.

  14. Wave-function engineering and absorption spectra in Si{sub 0.16}Ge{sub 0.84}/Ge{sub 0.94}Sn{sub 0.06}/Si{sub 0.16}Ge{sub 0.84} strained on relaxed Si{sub 0.10}Ge{sub 0.90} type I quantum well

    SciTech Connect (OSTI)

    Yahyaoui, N., E-mail: naima.yahyaoui@yahoo.fr, E-mail: moncef-said@yahoo.fr; Sfina, N.; Said, M., E-mail: naima.yahyaoui@yahoo.fr, E-mail: moncef-said@yahoo.fr [Laboratoire de la Matière Condensée et des Nanosciences (LMCN), Département de Physique, Faculté des Sciences de Monastir, Avenue de l'Environnement, 5019 Monastir (Tunisia); Lazzari, J.-L. [Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), UMR CNRS 7325, Aix-Marseille Université, Case 913, Campus de Luminy, 13288 Marseille cedex 9 (France); Bournel, A. [Institut d'Electronique Fondamentale (IEF), UMR CNRS 8622, Université Paris-Sud, Bât. 220, 91405 Orsay cedex (France)

    2014-01-21T23:59:59.000Z

    We theoretically investigate germanium-tin alloy as a semiconductor for the design of near infrared optical modulators in which the Ge{sub 1?x}Sn{sub x} alloy is the active region. We have calculated the electronic band parameters for heterointerfaces between strained Ge{sub 1?x}Sn{sub x} and relaxed Si{sub 1?y}Ge{sub y}. Then, a type-I strain-compensated Si{sub 0.10}Ge{sub 0.90}/Si{sub 0.16}Ge{sub 0.84}/Ge{sub 0.94}Sn{sub 0.06} quantum well heterostructure optimized in terms of compositions and thicknesses is studied by solving Schrödinger equation without and under applied bias voltage. The strong absorption coefficient (>1.5?×?10{sup 4}?cm{sup ?1}) and the shift of the direct transition under large Stark effect at 3?V are useful characteristics for the design of optoelectronic devices based on compressively strained IV-IV heterostructures at near infrared wavelengths.

  15. Wireless System Considerations When Implementing NERC Critical...

    Energy Savers [EERE]

    & Publications Recommended Practices Guide For Securing ZigBee Wireless Networks in Process Control System Environments Securing WLANs using 802.11i DOEOE National SCADA...

  16. North American Electric Reliability Corporation (NERC): Reliability

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of Contamination in Many DevilsForumEnginesVacantmagneticDepartment of

  17. North American Electric Reliability Corporation (NERC): Reliability

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOilNEW HAMPSHIREofNewsletter NewsletterGeneralof Energy

  18. Wireless System Considerations When Implementing NERC Critical

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China 2015ofDepartment of EnergyThe U.S.Department of EnergyToday,January 2007

  19. Wireless System Considerations When Implementing NERC Critical

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your DensityEnergy U.S.-China Electric VehicleCenters | Department ofoftoMay 8,EnergyWinning2

  20. Improvement in elastic properties of CuAl{sub 0.4}Fe{sub 1.6}O{sub 4} spinel ferrite by rapid thermal cooling

    SciTech Connect (OSTI)

    Modi, K. B., E-mail: kunalbmodi2003@yahoo.com; Shah, S. J., E-mail: kunalbmodi2003@yahoo.com; Pathak, T. K., E-mail: kunalbmodi2003@yahoo.com; Vasoya, N. H., E-mail: kunalbmodi2003@yahoo.com; Lakhani, V. K., E-mail: kunalbmodi2003@yahoo.com [Department of Physics, Saurashtra University, Rajkot-360005 (India); Yahya, A. K. [School of Physics and Materials Studies, University Technology MARA, 40450 Shah Alam, Selangor (Malaysia)

    2014-04-24T23:59:59.000Z

    The elastic properties of spinel ferrite composition, CuAl{sub 0.4}Fe{sub 1.6}O{sub 4}, quenched from final sintering temperature of 1373 K to liquid nitrogen temperature (? 80K) have been studied by means of X-ray powder diffractometry and pulse echo-overlap technique (9 MHz) at 300 K. The magnitude of elastic constants is found to enhance by 15% compared to slowly-cooled counterpart. The observed mechanical strengthening has been discussed in the light of compressive stress on the surface, with tensile stresses at interior regions and corresponding changes in structural parameters. The B{sub o}/G{sub o} ratio indicates the brittle nature of CuAl{sub 0.4}Fe{sub 1.6}O{sub 4}.

  1. Conditions for uniform growth of GaAs/sub 1-//sub x-italic/P/sub x-italic/ superlattices

    SciTech Connect (OSTI)

    Blakeslee, A.E.; Kibbler, A.; Wanlass, M.W.; Biefeld, R.M.

    1986-08-01T23:59:59.000Z

    Nonplanar morphology and compositional inhomogeneity are observed in GaAs/sub 1-//sub x-italic/P/sub x-italic/ superlattices when the phosphorus content is substantially different in adjacent sublayers. The main characteristic feature of the distortion is a series of ribbonlike regions running through the superlattice which etch at a faster rate and contain more phosphorus than the surrounding material and are also the source of clusters of dislocations. Morphological stability and a general decrease in dislocation density can be effected by decreasing the interlayer strain, i.e., compositional difference, between the superlattice sublayers.

  2. Glass formation and the third harmonic generation of Cu{sub 2}Se–GeSe{sub 2}–As{sub 2}Se{sub 3} glasses

    SciTech Connect (OSTI)

    Reshak, A. H., E-mail: maalidph@yahoo.co.uk [New Technologies-Research Centre, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Klymovych, O. S.; Zmiy, O. F. [Department of Inorganic and Physical Chemistry, Lesya Ukrainka Eastern European National University, Voli Av. 13, 43025 Lutsk (Ukraine); Myronchuk, G. L.; Zamuruyeva, O. V. [Department of Physics, Lesya Ukrainka Eastern European National University, Voli Av. 13, 43025 Lutsk (Ukraine); Alahmed, Z. A. [Department of Physics and Astronomy, King Saud University, Riyadh 11451 (Saudi Arabia); Chyský, J.; Bila, Jiri [Department of Instrumentation and Control Engineering, Faculty of Mechanical Engineering, CTU in Prague, Technicka 4, 166 07 Prague 6 (Czech Republic); Kamarudin, H. [Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia)

    2014-10-14T23:59:59.000Z

    We have performed the investigation of the nonlinear optical properties namely the third harmonic generation (THG) of the glass-formation region in the Cu{sub 2}Se–GeSe{sub 2}–As{sub 2}Se{sub 3} system. The samples were synthesized by direct single-temperature method from high-purity elementary substances. We have found that the value of disorder parameter ? depends on the composition of the glassy alloys. The measurements show that increasing the Cu{sub 2}Se concentration leads to increased slope of the absorption edge, which may be explained by the decrease of the height of random potential relief for the electrons in the tails of the state density which border the band edges. A very sharp increase in the THG at low temperature was observed. Significant enhancement in THG was obtained with decreasing the energy gap, which agreed well with the nonlinear optical susceptibilities obtained from other glasses.

  3. Influence of rare-earth ions on SiO{sub 2}-Na{sub 2}O-RE{sub 2}O{sub 3} glass structure.

    SciTech Connect (OSTI)

    Johnson, J. A.; Benmore, C. J.; Holland, D.; Du, J.; Beuneu, B.; Mekki, A. (X-Ray Science Division); (Univ. of Tennessee Space Institute); (Univ. of Warwick); (Univ.of North Texas); (Lab. Leon Brillouin); (King Fahd Univ. of Petroleum and Minerals)

    2011-01-27T23:59:59.000Z

    Praseodymium and europium sodium silicate glasses of nominal composition (SiO{sub 2}){sub 0.70-x}(Na{sub 2}O){sub 0.30}(RE{sub 2}O{sub 3}){sub x}, where RE is the rare earth and 0 {le} x {le} 0.10, were studied by neutron and high-energy x-ray scattering and classical molecular dynamics simulations. The observation of a significant x-ray intensity in doped as compared to un-doped glasses is indicative of RE-RE correlations at a distance of {approx} 3.7-3.9 {angstrom}, much shorter than would be expected for a homogeneous distribution, suggesting that clustering of the rare-earth cations occurs in both these glass systems at low concentrations. Above x = 0.075 (nominal), minimal changes in this region indicate that the RE atoms are incorporated much more randomly into the glass structure. The molecular dynamics simulations suggest that the rare-earth ions enter the sodium-rich regions in the sodium silicate glasses and act as modifiers. A cluster analysis performed on the model systems indicates that the tendency for clustering is higher in praseodymium-containing glasses than in the europium glasses.

  4. The crystal structure of Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O and its decomposition product, {beta}-Yb{sub 2}(SO{sub 4}){sub 3}

    SciTech Connect (OSTI)

    Mills, Stuart J., E-mail: smills@museum.vic.gov.au [Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z4 (Canada); Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California 90007 (United States); Petricek, Vaclav [Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, 182 21 Praha (Czech Republic); Kampf, Anthony R. [Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California 90007 (United States); Herbst-Imer, Regine [Department of Structural Chemistry, University of Goettingen, Tammannstrasse 4, 37077 Goettingen (Germany); Raudsepp, Mati [Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z4 (Canada)

    2011-09-15T23:59:59.000Z

    Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O, synthesised by hydrothermal methods at 220(2) deg. C, has been investigated by single crystal X-ray diffraction. Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O crystallises in space group Cmc2{sub 1} and is isostructural with Lu{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O. The crystal structure has been refined to R{sub 1}=0.0145 for 3412 reflections [F{sub o}>3{sigma}(F)], and 0.0150 for all 3472 reflections. The structure of Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O is a complex framework of YbO{sub 6} octahedra, YbO{sub 8} and YbO{sub 5}(H{sub 2}O){sub 3} polyhedra and SO{sub 4} tetrahedra. Thermal data shows that Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O decomposes between 120 and 190 deg. C to form {beta}-Yb{sub 2}(SO{sub 4}){sub 3}. The structure of a twinned crystal of {beta}-Yb{sub 2}(SO{sub 4}){sub 3} was solved and refined using an amplimode refinement in R3c with an R{sub 1}=0.0755 for 8944 reflections [F{sub o}>3{sigma}(F)], and 0.1483 for all 16,361 reflections. {beta}-Yb{sub 2}(SO{sub 4}){sub 3} has a unique structural topology based on a 3D network of pinwheels. - Graphical abstract: Octahedral-tetrahedral linkages found in Y{sub 2}(SO{sub 4}){sub 3} [and Er{sub 2}(SO{sub 4}){sub 3}] and ss-Yb{sub 2}(SO{sub 4}){sub 3}. Highlights: > The crystal structure and decomposition reactions of Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O. > The crystal structure of a twinned crystal of {beta}-Yb{sub 2}(SO{sub 4}){sub 3}. > Comparison of the structures of {beta}-Yb{sub 2}(SO{sub 4}){sub 3} and Y{sub 2}(SO{sub 4}){sub 3}.

  5. Measurement of the B<sub>-c>meson lifetime in the decay B<sub>-c>?J/???

    SciTech Connect (OSTI)

    Aaltonen, T.; Álvarez González, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Auerbach, B.; Aurisano, A.; Azfar, F.; Badgett, W.; Bae, T.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartos, P.; Bauce, M.; Bedeschi, F.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Bhatti, A.; Bisello, D.; Bizjak, I.; Bland, K. R.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brigliadori, L.; Bromberg, C.; Brucken, E.; Budagov, J.; Budd, H. S.; Burkett, K.; Busetto, G.; Bussey, P.; Buzatu, A.; Calamba, A.; Calancha, C.; Camarda, S.; Campanelli, M.; Campbell, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Carron, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Chlebana, F.; Cho, K.; Chokheli, D.; Chung, W. H.; Chung, Y. S.; Ciocci, M. A.; Clark, A.; Clarke, C.; Compostella, G.; Convery, M. E.; Conway, J.; Corbo, M.; Cordelli, M.; Cox, C. A.; Cox, D. J.; Crescioli, F.; Cuevas, J.; Culbertson, R.; Dagenhart, D.; d’Ascenzo, N.; Datta, M.; de Barbaro, P.; Dell’Orso, M.; Demortier, L.; Deninno, M.; Devoto, F.; d’Errico, M.; Di Canto, A.; Di Ruzza, B.; Dittmann, J. R.; D’Onofrio, M.; Donati, S.; Dong, P.; Dorigo, M.; Dorigo, T.; Ebina, K.; Elagin, A.; Eppig, A.; Erbacher, R.; Errede, S.; Ershaidat, N.; Eusebi, R.; Farrington, S.; Feindt, M.; Fernandez, J. P.; Field, R.; Flanagan, G.; Forrest, R.; Frank, M. J.; Franklin, M.; Freeman, J. C.; Funakoshi, Y.; Furic, I.; Gallinaro, M.; Garcia, J. E.; Garfinkel, A. F.; Garosi, P.; Gerberich, H.; Gerchtein, E.; Giagu, S.; Giakoumopoulou, V.; Giannetti, P.; Gibson, K.; Ginsburg, C. M.; Giokaris, N.; Giromini, P.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Goldschmidt, N.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Grinstein, S.; Grosso-Pilcher, C.; Group, R. C.; Guimaraes da Costa, J.; Hahn, S. R.; Halkiadakis, E.; Hamaguchi, A.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, D.; Hare, M.; Harr, R. F.; Hatakeyama, K.; Hays, C.; Heck, M.; Heinrich, J.; Herndon, M.; Hewamanage, S.; Hocker, A.; Hopkins, W.; Horn, D.; Hou, S.; Hughes, R. E.; Hurwitz, M.; Husemann, U.; Hussain, N.; Hussein, M.; Huston, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jindariani, S.; Jones, M.; Joo, K. K.; Jun, S. Y.; Junk, T. R.; Kamon, T.; Karchin, P. E.; Kasmi, A.; Kato, Y.; Ketchum, W.; Keung, J.; Khotilovich, V.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. K.; Kim, Y. J.; Kimura, N.; Kirby, M.; Klimenko, S.; Knoepfel, K.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Krop, D.; Kruse, M.; Krutelyov, V.; Kuhr, T.; Kurata, M.; Kwang, S.; Laasanen, A. T.; Lami, S.; Lammel, S.; Lancaster, M.; Lander, R. L.; Lannon, K.; Lath, A.; Latino, G.; LeCompte, T.; Lee, E.; Lee, H. S.; Lee, J. S.; Lee, S. W.; Leo, S.; Leone, S.; Lewis, J. D.; Limosani, A.; Lin, C.-J.; Lindgren, M.; Lipeles, E.; Lister, A.; Litvintsev, D. O.; Liu, C.; Liu, H.; Liu, Q.; Liu, T.; Lockwitz, S.; Loginov, A.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lys, J.; Lysak, R.; Madrak, R.; Maeshima, K.; Maestro, P.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Margaroli, F.; Marino, C.; Martínez, M.; Mastrandrea, P.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McFarland, K. S.; McIntyre, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Mesropian, C.; Miao, T.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Mondragon, M. N.; Moon, C. S.; Moore, R.; Morello, M. J.; Morlock, J.; Movilla Fernandez, P.; Mukherjee, A.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nakano, I.; Napier, A.; Nett, J.; Neu, C.; Neubauer, M. S.; Nielsen, J.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Ortolan, L.; Pagan Griso, S.; Pagliarone, C.; Palencia, E.; Papadimitriou, V.; Paramonov, A. A.; Patrick, J.; Pauletta, G.; Paulini, M.; Paus, C.; Pellett, D. E.; Penzo, A.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pondrom, L.; Poprocki, S.; Potamianos, K.; Prokoshin, F.; Pranko, A.; Ptohos, F.; Punzi, G.; Rahaman, A.; Ramakrishnan, V.; Ranjan, N.; Redondo, I.; Renton, P.; Rescigno, M.; Riddick, T.; Rimondi, F.; Ristori, L.; Robson, A.; Rodrigo, T.; Rodriguez, T.; Rogers, E.; Rolli, S.; Roser, R.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Safonov, A.; Sakumoto, W. K.

    2013-01-01T23:59:59.000Z

    The lifetime of the B<sub>-c> meson is measured using 272 exclusive B<sub>-c>?J/?(?????)?? decays reconstructed in data from proton-antiproton collisions corresponding to an integrated luminosity of 6.7 fb?¹ recorded by the CDF II detector at the Fermilab Tevatron. The lifetime of the B<sub>-c>meson is measured to be <sub>?(B-c>)=0.452±0.048(stat)±0.027(syst) ps. This is the first measurement of the B<sub>-c> meson lifetime in a fully reconstructed hadronic channel, and it agrees with previous results and has comparable precision.

  6. Carrier transport properties of nanocrystalline Er{sub 3}N@C{sub 80}

    SciTech Connect (OSTI)

    Sun, Yong, E-mail: sun@ele.kyutech.ac.jp; Maeda, Yuki; Sezaimaru, Hiroki; Sakaino, Masamichi [Department of Applied Science for Integrated System Engineering, Kyushu Institute of Technology, Senshuimachi, Tobata, Kitakyushu, Fukuoka 804-8550 (Japan); Kirimoto, Kenta [Department of Electrical and Electronic Engineering, Kitakyushu National College of Technology, 5-20-1 shii, Kokuraminami, Kitakyushu, Fukuoka 802-0985 (Japan)

    2014-07-21T23:59:59.000Z

    Electrical transport properties of the nanocrystalline Er{sub 3}N@C{sub 80} with fcc crystal structure were characterized by measuring both temperature-dependent d.c. conductance and a.c. impedance. The results showed that the Er{sub 3}N@C{sub 80} sample has characteristics of n-type semiconductor and an electron affinity larger than work function of gold metal. The Er{sub 3}N@C{sub 80}/Au interface has an ohmic contact behavior and the contact resistance was very small as compared with bulk resistance of the Er{sub 3}N@C{sub 80} sample. The charge carriers in the sample were thermally excited from various trapped levels and both acoustic phonon and ionic scatterings become a dominant process in different temperature regions, respectively. At temperatures below 250?K, the activation energy of the trapped carrier was estimated to be 35.5?meV, and the ionic scattering was a dominant mechanism. On the other hand, at temperatures above 350?K, the activation energy was reduced to 15.9?meV, and the acoustic phonon scattering was a dominant mechanism. In addition, a polarization effect from the charge carrier was observed at low frequencies below 2.0 MHz, and the relative intrinsic permittivity of the Er{sub 3}N@C{sub 80} nanocrystalline lattice was estimated to be 4.6 at frequency of 5.0 MHz.

  7. Optical microcavities and enhanced electroluminescence from electroformed Al-Al{sub 2}O{sub 3}-Ag diodes

    SciTech Connect (OSTI)

    Hickmott, T. W. [Department of Physics, State University of New York at Albany, Albany, New York 12222 (United States)

    2013-12-21T23:59:59.000Z

    Electroluminescence (EL) and electron emission into vacuum (EM) occur when a non-destructive dielectric breakdown of Al-Al{sub 2}O{sub 3}-Ag diodes, electroforming, results in the development of a filamentary region in which current-voltage (I-V) characteristics exhibit voltage-controlled negative resistance. The temperature dependence of I-V curves, EM, and, particularly, EL of Al-Al{sub 2}O{sub 3}-Ag diodes with anodic Al{sub 2}O{sub 3} thicknesses between 12?nm and 30?nm, has been studied. Two filters, a long-pass (LP) filter with transmission of photons with energies less than 3.0?eV and a short-pass (SP) filter with photon transmission between 3.0 and 4.0?eV, have been used to characterize EL. The voltage threshold for EL with the LP filter, V{sub LP}, is ?1.5?V. V{sub LP} is nearly independent of Al{sub 2}O{sub 3} thickness and of temperature and is 0.3–0.6?V less than the threshold voltage for EL for the SP filter, V{sub SP}. EL intensity is primarily between 1.8 and 3.0?eV when the bias voltage, V{sub S} ? 7?V. EL in the thinnest diodes is enhanced compared to EL in thicker diodes. For increasing V{sub S}, for diodes with the smallest Al{sub 2}O{sub 3} thicknesses, there is a maximum EL intensity, L{sub MX}, at a voltage, V{sub LMX}, followed by a decrease to a plateau. L{sub MX} and EL intensity at 4.0?V in the plateau region depend exponentially on Al{sub 2}O{sub 3} thickness. The ratio of L{sub MX} at 295?K for a diode with 12?nm of Al{sub 2}O{sub 3} to L{sub MX} for a diode with 25?nm of Al{sub 2}O{sub 3} is ?140. The ratio of EL intensity with the LP filter to EL intensity with the SP filter, LP/SP, varies between ?3 and ?35; it depends on Al{sub 2}O{sub 3} thickness and V{sub S}. Enhanced EL is attributed to the increase of the spontaneous emission rate of a dipole in a non-resonant optical microcavity. EL photons interact with the Ag and Al films to create surface plasmon polaritons (SPPs) at the metal-Al{sub 2}O{sub 3} interfaces. SPPs generate large electromagnetic fields in the filamentary region of the electroformed Al-Al{sub 2}O{sub 3}-Ag diode, which then acts as an optical microcavity. A model is proposed for electronic processes in electroformed Al-Al{sub 2}O{sub 3}-Ag diodes.

  8. Coexistence of considerable inter-particle interactions and spin-glass behavior in La{sub 0.7}Ca{sub 0.3}MnO{sub 3} nanoparticles

    SciTech Connect (OSTI)

    Thanh, T. D., E-mail: thanhxraylab@yahoo.com [Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Institute of Materials Science, VAST, 18-Hoang Quoc Viet, Hanoi (Viet Nam); Manh, D. H.; Phuc, N. X. [Institute of Materials Science, VAST, 18-Hoang Quoc Viet, Hanoi (Viet Nam); Phan, T. L.; Yu, S. C., E-mail: scyu@chungbuk.ac.kr [Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Phong, P. T. [Nha Trang Pedagogic College, 1 Nguyen Chanh Street, Nha Trang (Viet Nam); Hung, L. T. [Department of Physics, University of Vinh, Nghe An (Viet Nam)

    2014-05-07T23:59:59.000Z

    We have studied the magnetic and spin-glass (SG) properties of La{sub 0.7}Ca{sub 0.3}MnO{sub 3} single-crystalline nanoparticles, which were prepared by the mechanical milling method with different milling times (t{sub m}). Analyzing the susceptibility data in the paramagnetic region indicates both ferromagnetic (FM) and anti-FM interactions coexisting in nanoparticles. Additionally, there is a peak associated with the freezing temperature (T{sub f}) appearing on the real part curve of the ac susceptibility, ??(T). The T{sub f} value increases with increasing frequency as expected for SG systems. The SG behavior was also checked by using the criterion parameter c?=??T{sub f}/T{sub f}?(log{sub 10}f), and the power law ??=??{sub 0}(T/T{sub g} ? 1){sup ?z?}. The obtained values of c???5?×?10{sup ?2}, ?{sub 0} ? 10{sup ?5} s and z? ? 2–3 are consistent with those expected for SG-like systems, suggesting an existence of a SG phase transition at T{sub g} below T{sub f}, which decreases with decreasing ?D?. Basing on ln(f) versus T{sub f} data, and the Néel-Arrhenius model [ln(f)?=?ln(f{sub 0}) - E{sub a}/k{sub B}T] and Vogel–Fulcher law [ln(f)?=?ln(f{sub 0}) - E{sub a}/k{sub B}(T - T{sub 0})], the Larmor frequency (f{sub 0}), activation energy (E{sub a}) and effective temperature (T{sub 0}) for the samples with different ?D? were determined. Obtained results indicate the existence a strong interaction between nanoparticles.

  9. Syntheses, crystal structures, and properties of three new metal selenites Na{sub 2}Co{sub 2}(SeO{sub 3}){sub 3}, Na{sub 2}Co{sub 1.67}Ni{sub 0.33}(SeO{sub 3}){sub 3}, and Na{sub 2}Ni{sub 2}(SeO{sub 3}){sub 3}

    SciTech Connect (OSTI)

    Yuan Xiaoqing [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Feng Meiling, E-mail: fml@fjirsm.ac.c [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, the Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Li Jianrong [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, the Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Huang Xiaoying, E-mail: xyhuang@fjirsm.ac.c [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)

    2010-09-15T23:59:59.000Z

    Three new sodium cobalt (nickel) selenite compounds, namely, Na{sub 2}Co{sub 2}(SeO{sub 3}){sub 3}, Na{sub 2}Co{sub 1.67}Ni{sub 0.33}(SeO{sub 3}){sub 3}, and Na{sub 2}Ni{sub 2}(SeO{sub 3}){sub 3} have been hydro-/solvothermally synthesized in the mixed solvents of acetonitrile and water. Single-crystal X-ray diffraction analyses reveal that these isostructural compounds belong to the orthorhombic Cmcm space group and their structures feature three-dimensional open frameworks constructed by the two-dimensional layers of [MSeO{sub 3}] pillared by the [SeO{sub 3}]{sup 2-} groups. The two different types of Na{sup +} ions reside in the intersecting two-dimensional channels parallel to the a- and c-axes, respectively. Their thermal properties have been investigated via TGA-DSC. The magnetic measurements indicate the existence of the antiferromagnetic interactions in these compounds. - Graphical abstract: Three new isostructural metal selenites, Na{sub 2}Co{sub 2}(SeO{sub 3}){sub 3}, Na{sub 2}Co{sub 1.67}Ni{sub 0.33}(SeO{sub 3}){sub 3}, and Na{sub 2}Ni{sub 2}(SeO{sub 3}){sub 3} have been hydro-/solvothermally synthesized and characterized. Their structures feature three-dimensional open frameworks with Na{sup +}-occupied channels.

  10. EXPLORING THE CENTRAL SUB-PARSEC REGION OF THE {gamma}-RAY BRIGHT RADIO GALAXY 3C 84 WITH VLBA AT 43 GHz IN THE PERIOD OF 2002-2008

    SciTech Connect (OSTI)

    Suzuki, Kenta [Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Nagai, Hiroshi; Kino, Motoki; Kobayashi, Hideyuki [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Kataoka, Jun [Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan); Asada, Keiichi; Inoue, Makoto [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan, R.O.C. (China); Doi, Akihiro [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Yoshinodai 3-1-1, Chuo-ku, Sagamihara 252-5210 (Japan); Orienti, Monica; Giovannini, Gabriele; Giroletti, Marcello [INAF Istituto di Radioastronomia, via Gobetti 101, 40129 Bologna (Italy); Laehteenmaeki, Anne; Tornikoski, Merja; Leon-Tavares, Jonathan [Aalto University Metsaehovi Radio Observatory, Metsaehovintie 114, FIN-02540 Kylmaelae (Finland); Bach, Uwe [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, 53121 Bonn (Germany); Kameno, Seiji [Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065 (Japan)

    2012-02-20T23:59:59.000Z

    Following the discovery of a new radio component right before the GeV {gamma}-ray detection since 2008 August by the Fermi Gamma-ray Space Telescope, we present a detailed study of the kinematics and light curve on the central sub-parsec scale of 3C 84 using the archival Very Long Baseline Array 43 GHz data covering the period between 2002 January and 2008 November. We find that the new component 'C3', previously reported by the observations with the Very Long Baseline Interferometer Exploration of Radio Astrometry, was already formed in 2003. The flux density of C3 increases moderately until 2008, and then it becomes brighter rapidly after 2008. The radio core, C1, also shows a similar trend. The apparent speed of C3 with reference to the core C1 shows moderate acceleration from 0.10c to 0.47c between 2003 November and 2008 November, but is still sub-relativistic. We further try to fit the observed broadband spectrum by the one-zone synchrotron self-Compton model using the measured apparent speed of C3. The fit can reproduce the observed {gamma}-ray emission, but does not agree with the observed radio spectral index between 22 and 43 GHz.

  11. Effects of Mg doping on the remarkably enhanced electrochemical performance of Na<sub>3sub>V>2sub>(PO>4sub>)>3sub> cathode materials for sodium ion batteries

    SciTech Connect (OSTI)

    Li, Hui [Beijing Inst. of Technology, Beijing (China). Key Lab. of Environmental Science and Engineering, School of Chemical Engineering and Environment; Yu, Xiqian [Brookhaven National Lab. (BNL), Upton, NY (United States). Chemistry Dept.; Bai, Ying [Beijing Inst. of Technology, Beijing (China). Key Lab. of Environmental Science and Engineering, School of Chemical Engineering and Environment; Wu, Feng [Beijing Inst. of Technology, Beijing (China). Key Lab. of Environmental Science and Engineering, School of Chemical Engineering and Environment; Wu, Chuan [Beijing Inst. of Technology, Beijing (China). Key Lab. of Environmental Science and Engineering, School of Chemical Engineering and Environment; Liu, Liang-Yu [Beijing Inst. of Technology, Beijing (China). Key Lab. of Environmental Science and Engineering, School of Chemical Engineering and Environment; Yang, Xiao-Qing [Brookhaven National Lab. (BNL), Upton, NY (United States). Chemistry Dept.

    2015-01-01T23:59:59.000Z

    Na<sub>3sub>V>2-xsub>Mgx(PO>4sub>)>3sub>/C composites with different Mg2+ doping contents (x=0, 0.01, 0.03, 0.05, 0.07 and 0.1) were prepared by a facile sol-gel method. The doping effects on the crystal structure were investigated by XRD, XPS and EXAFS. The results show that low dose doping Mg2+ does not alter the structure of the material, and magnesium is successfully substituted for vanadium site. The Mg doped Na<sub>3sub>V>2-xsub>Mgx(PO>4sub>)>3sub>/C composites exhibit significant improvements on the electrochemistry performances in terms of the rate capability and cycle performance, especially for the Na<sub>3sub>V>1.95sub>Mg>0.05sub>(PO>4sub>)>3sub>/C. For example, when the current density increased from 1 C to 30 C, the specific capacity only decreased from 112.5 mAh g-1 to 94.2 mAh g-1 showing very good rate capability. Moreover, even cycling at a high rate of 20 C, an excellent capacity retention of 81% is maintained from the initial value of 106.4 mAh g-1 to 86.2 mAh g-1 at the 50th cycle. Enhanced rate capability and cycle performance can be attributed to the optimized particle size, structural stability and enhanced ionic and electronic conductivity induced by Mg doping.

  12. Quantum cascade laser investigations of CH{sub 4} and C{sub 2}H{sub 2} interconversion in hydrocarbon/H{sub 2} gas mixtures during microwave plasma enhanced chemical vapor deposition of diamond

    SciTech Connect (OSTI)

    Ma Jie; Cheesman, Andrew; Ashfold, Michael N. R. [School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom); Hay, Kenneth G.; Wright, Stephen; Langford, Nigel; Duxbury, Geoffrey [Department of Physics, University of Strathclyde, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG (United Kingdom); Mankelevich, Yuri A. [Skobel'tsyn Institute of Nuclear Physics, Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation)

    2009-08-01T23:59:59.000Z

    CH{sub 4} and C{sub 2}H{sub 2} molecules (and their interconversion) in hydrocarbon/rare gas/H{sub 2} gas mixtures in a microwave reactor used for plasma enhanced diamond chemical vapor deposition (CVD) have been investigated by line-of-sight infrared absorption spectroscopy in the wavenumber range of 1276.5-1273.1 cm{sup -1} using a quantum cascade laser spectrometer. Parameters explored include process conditions [pressure, input power, source hydrocarbon, rare gas (Ar or Ne), input gas mixing ratio], height (z) above the substrate, and time (t) after addition of hydrocarbon to a pre-existing Ar/H{sub 2} plasma. The line integrated absorptions so obtained have been converted to species number densities by reference to the companion two-dimensional (r,z) modeling of the CVD reactor described in Mankelevich et al. [J. Appl. Phys. 104, 113304 (2008)]. The gas temperature distribution within the reactor ensures that the measured absorptions are dominated by CH{sub 4} and C{sub 2}H{sub 2} molecules in the cool periphery of the reactor. Nonetheless, the measurements prove to be of enormous value in testing, tensioning, and confirming the model predictions. Under standard process conditions, the study confirms that all hydrocarbon source gases investigated (methane, acetylene, ethane, propyne, propane, and butane) are converted into a mixture dominated by CH{sub 4} and C{sub 2}H{sub 2}. The interconversion between these two species is highly dependent on the local gas temperature and the H atom number density, and thus on position within the reactor. CH{sub 4}->C{sub 2}H{sub 2} conversion occurs most efficiently in an annular shell around the central plasma (characterized by 1400sub gas}<2200 K), while the reverse transformation C{sub 2}H{sub 2}->CH{sub 4} is favored in the more distant regions where T{sub gas}<1400 K. Analysis of the multistep interconversion mechanism reveals substantial net consumption of H atoms accompanying the CH{sub 4}->C{sub 2}H{sub 2} conversion, whereas the reverse C{sub 2}H{sub 2}->CH{sub 4} process only requires H atoms to drive the reactions; H atoms are not consumed by the overall conversion.

  13. La??<sub>xSrx>CuO? superconductor nanowire devices

    SciTech Connect (OSTI)

    Litombe, N. E. [Harvard Univ., Cambridge, MA (United States); Brookhaven National Lab. (BNL), Upton, NY (United States); Bollinger, A. T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hoffman, J. E. [Harvard Univ., Cambridge, MA (United States); Bozovic, I. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-11-01T23:59:59.000Z

    La??<sub>xSrx>CuO? nanowire devices have been fabricated and characterized using electrical transport measurements. Nanowires with widths down to 80 nm are patterned using high-resolution electron beam lithography. However, the narrowest nanowires show incomplete superconducting transitions with some residual resistance at T = 4 K. Here, we report on refinement of the fabrication process to achieve narrower nanowire devices with complete superconducting transitions, opening the path to the study of novel physics arising from dimension-limited superconductivity on the nanoscale.

  14. Structure and physical properties of EuTa{sub 2}O{sub 6} tungsten bronze polymorph

    SciTech Connect (OSTI)

    Kolodiazhnyi, T., E-mail: kolodiazhnyi.taras@nims.go.jp; Sakurai, H.; Vasylkiv, O.; Borodianska, H. [National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Forbes, S.; Mozharivskyj, Y. [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S4M1 (Canada)

    2014-08-11T23:59:59.000Z

    A tetragonal tungsten bronze (TTB) polymorph of EuTa{sub 2}O{sub 6} was prepared and analyzed. EuTa{sub 2}O{sub 6} crystallizes in the centrosymmetric Pnam space group (with unit cell: a?=?12.3693, b?=?12.4254, and c?=?7.7228?Å) isomorphous with orthorhombic ?-SrTa{sub 2}O{sub 6}. In contrast to early reports, we see no evidence of deviation from paramagnetic Curie-Weiss behavior among the Eu{sup 2+} 4f{sup 7}spins in EuTa{sub 2}O{sub 6} down to 2?K. Dielectric constant shows a broad peak at ca. 50?K with dielectric dispersion resembling diffuse phase transition. The relaxation time, however, follows a simple (non-freezing) thermally activated process with an activation energy of 92?meV and an attempt frequency of f{sub 0}?=?5.79?×?10{sup 12?}Hz. A thermal conductivity of EuTa{sub 2}O{sub 6} shows a low-temperature (T???30?K) “plateau” region reminiscent of a glass-like behaviour in Nb-based TTB compounds. This behaviour can be attributed to the loosely bound Eu{sup 2+} ions occupying large tricapped trigonal prismatic sites in the EuTa{sub 2}O{sub 6} structure.

  15. Cation distribution in Ni{sub 1?x}Zn{sub x}Fe{sub 2}O{sub 4} using X-ray absorption spectroscopy

    SciTech Connect (OSTI)

    Yadav, A. K., E-mail: akyadav@barc.gov.in; Jha, S. N.; Bhattacharyya, D.; Sahoo, N. K. [Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai - 400094 (India); Jadhav, J.; Biswas, S. [Department of Physics, The LNM Institute of Information Technology, Jaipur-302031 (India)

    2014-04-24T23:59:59.000Z

    Spinel ferrite samples of Ni{sub 1?x}Zn{sub x}Fe{sub 2}O{sub 4} (for x=0.2, 0.4, 0.5, 0.6 and 0.8) nanoparticles prepared by a novel chemical synthesis method have been characterized by X-ray Absorption Spectroscopy (XAS) technique to investigate the distribution of cations in the unit cell. XANES region clearly shows that as Ni concentration increases, the pre-edge feature, which is a characteristic of tetrahedral coordination of Fe, is enhanced. A quantitative determination of the relative occupancy of iron cation in the octahedral and tetrahedral sites of the spinel structure was obtained from EXAFS data analysis. It has been found that as atomic fraction of Ni is increased from 0.2 to 0.8, Fe occupancy at tetrahedral to octahedral sites is increased from 13:87 and to 39:61.

  16. Abnormal thermal conductivity in tetragonal tungsten bronze Ba{sub 6?x}Sr{sub x}Nb{sub 10}O{sub 30}

    SciTech Connect (OSTI)

    Kolodiazhnyi, T., E-mail: kolodiazhnyi.taras@nims.go.jp; Sakurai, H.; Vasylkiv, O.; Borodianska, H. [National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Mozharivskyj, Y. [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S4M1 (Canada)

    2014-03-17T23:59:59.000Z

    Ba{sub 6?x}Sr{sub x}Nb{sub 10}O{sub 30} solid solution with 0???x???6 crystallizes in centrosymmetric tetragonal “tungsten bronze” structure (space group P4/mbm). We report on the x dependence of thermal conductivity of polycrystalline samples measured in the 2–400?K temperature interval. Substitution of Sr for Ba brings about a significant decrease in thermal conductivity at x???3 accompanied by development of a low-temperature (T???10–30?K) “plateau” region reminiscent of a glass-like compounds. We explain this behaviour based on a size-driven site occupancy and atomic displacement parameters associated with an alkaline earth atomic positions in the title compounds.

  17. Low NO.sub.x multistage combustor

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Breault, Ronald W. (Newington, NH); Litka, Anthony F. (Hanover, MA); McClaine, Andrew W. (Lexington, MA); Shukla, Kailash (Boxborough, MA)

    2000-01-01T23:59:59.000Z

    A high efficiency, Vortex Inertial Staged Air (VIStA) combustor provides ultra-low NO.sub.X production of about 20 ppmvd or less with CO emissions of less than 50 ppmvd, both at 3% O.sub.2. Prompt NO.sub.X production is reduced by partially reforming the fuel in a first combustion stage to CO and H.sub.2. This is achieved in the first stage by operating with a fuel rich mixture, and by recirculating partially oxidized combustion products, with control over stoichiometry, recirculation rate and residence time. Thermal NO.sub.X production is reduced in the first stage by reducing the occurrence of high temperature combustion gas regions. This is achieved by providing the first stage burner with a thoroughly pre-mixed fuel/oxidant composition, and by recirculating part of the combustion products to further mix the gases and provide a more uniform temperature in the first stage. In a second stage combustor thermal NO.sub.X production is controlled by inducing a large flow of flue gas recirculation in the second stage combustion zone to minimize the ultimate temperature of the flame. One or both of the first and second stage burners can be cooled to further reduce the combustion temperature and to improve the recirculation efficiency. Both of these factors tend to reduce production of NO.sub.X.

  18. Scaling of Dynamic Spin Correlations in BaCu<sub>2sub>(Si>0.5sub>Ge>0.5sub>)>2sub>O>7sub>

    SciTech Connect (OSTI)

    Zheludev, Andrey I [ORNL; Masuda, T. [Yokohama City University, Japan; Dhalenne, G. [Universite Paris Sud, Orsay, France; Revcolevschi, A. [Universite Paris Sud, Orsay, France; Frost, C. [ISIS Facility, Rutherford Appleton Laboratory; Perring, T. G. [ISIS Facility, Rutherford Appleton Laboratory

    2007-01-01T23:59:59.000Z

    The magnetic dynamic structure factor of the one-dimensional S=1/2 chain system BaCu{sub 2}(Si{sub 0.5}Ge{sub 0.5}){sub 2}O{sub 7} is studied in a wide range of energy transfers and temperatures. Contrary to previous erroneous reports [T. Masuda et al., Phys. Rev. Lett. 93, 077206 (2004)], the scaling properties observed in the range 0.5-25 meV are found to be fully consistent with expectations for a Luttinger spin liquid. At higher energies, a breakdown of scaling laws is observed and attributed to lattice effects. The results are complementary to those found in literature for other S=1/2 chain compounds, such as KCuF{sub 3} and Cu benzoate.

  19. Structural characterization of the CeO{sub 2}/Gd{sub 2}O{sub 3} mixed system by synchrotron X-ray diffraction

    SciTech Connect (OSTI)

    Artini, Cristina, E-mail: c.artini@ge.ieni.cnr.it [Dipartimento di Chimica e Chimica Industriale, Universita degli Studi di Genova, Via Dodecaneso 31, 16146 Genova (Italy); Costa, Giorgio A., E-mail: costa@chimica.unige.it [Dipartimento di Chimica e Chimica Industriale, Universita degli Studi di Genova, Via Dodecaneso 31, 16146 Genova (Italy); CNR-SPIN Genova, Corso Perrone 24, 16152 Genova (Italy); Pani, Marcella, E-mail: marcella@chimica.unige.it [Dipartimento di Chimica e Chimica Industriale, Universita degli Studi di Genova, Via Dodecaneso 31, 16146 Genova (Italy); Lausi, Andrea, E-mail: andrea.lausi@elettra.trieste.it [Sincrotrone Trieste S.C.p.A., ss 14, km 163, 5, 34149 Basovizza, Trieste (Italy); Plaisier, Jasper, E-mail: jasper.plaisier@elettra.trieste.it [Sincrotrone Trieste S.C.p.A., ss 14, km 163, 5, 34149 Basovizza, Trieste (Italy)

    2012-06-15T23:59:59.000Z

    The structural determination of the CeO{sub 2}/Gd{sub 2}O{sub 3} mixed system is a non-trivial problem because of the close resemblance between the ionic sizes of Ce{sup 4+} and Gd{sup 3+} and between the crystal structures of CeO{sub 2} and Gd{sub 2}O{sub 3}. (Ce{sub 1-x}Gd{sub x})O{sub 2-x/2} powder samples with x ranging between 0 and 1 have been synthesized by coprecipitation of mixed oxalates and subsequent thermal decomposition in air at 1200 Degree-Sign C followed by slow cooling. Synchrotron powder X-ray diffraction data were collected and refined by the Rietveld method. Lattice parameters do not follow Vegard's law and no peak splitting has been observed for any composition, meaning that no biphasic regions exist over the whole compositional range. The same hybrid structural model - a proper mixture of the structures of the two pure oxides - was used for the refinements, allowing to account for the data observed. - graphical abstract: Substituting Ce{sup 4+} by Gd{sup 3+}, a gradual transition from the F structure (typical of CeO{sub 2}) to the C structure (typical of Gd{sub 2}O{sub 3}) takes place. The lattice parameters do not follow Vegard's law. Highlights: Black-Right-Pointing-Pointer A structural study of Ce-Gd mixed oxides has been performed. Black-Right-Pointing-Pointer In (Ce{sub 1-x}Gd{sub x})O{sub 2-x/2} a solid solution forms for 0{<=}x{<=}0.3. Black-Right-Pointing-Pointer For x>0.3 a gradual transition from the C to the F structure is observed. Black-Right-Pointing-Pointer Lattice parameters do not follow Vegard's law.

  20. Lu<sub>1-xsub>I>3sub>:Cex>--a scintillator for gamma ray spectroscopy and time-of-flight PET

    DOE Patents [OSTI]

    Shah, Kanai S.

    2007-02-06T23:59:59.000Z

    The present invention concerns very fast scintillator materials comprising lutetium iodide doped with Cerium (Lu<sub>1-xsub>I>3sub>:Cex>; LuI<sub>3sub>:Ce). The LuI<sub>3 sub>scintillator material has surprisingly good characteristics including high light output, high gamma ray stopping efficiency, fast response, low cost, good proportionality, and minimal afterglow that the material is useful for gamma ray spectroscopy, medical imaging, nuclear and high energy physics research, diffraction, non-destructive testing, nuclear treaty verification and safeguards, and geological exploration. The timing resolution of the scintillators of the present invention provide compositions capable of resolving the position of an annihilation event within a portion of a human body cross-section.

  1. Airborne measurements during the Arctic stratospheric experiment: Observation of O[sub 3] and NO[sub 2

    SciTech Connect (OSTI)

    Pfeilsticker, K.; Platt, U. (Univ. of Heidelberg (Germany))

    1994-06-22T23:59:59.000Z

    This paper reports on aircraft based measurements of ozone, O[sub 4], NO[sub 2], and NO[sub 3] using differential optical absorption spectroscopy. These measurements were made during EASOE, over a region from 60[degrees]W to 60[degrees]E, and 48[degrees]N to 85[degrees]N. The presence of volcanic aerosols from Mt Pinatubo affected the results.

  2. U.S. Energy Information Administration (EIA)

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    Electricity and Renewable Fuel Tables (tables 73-120) Electric Power Projections for Electricity Market Module Regions - NERC Region Map Table 73. Texas Regional Entity Table...

  3. U.S. Energy Information Administration (EIA)

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    Electricity and Renewable Fuel Tables (tables 73-120) Electric Power Projections for Electricity Market Module Regions (NERC Region Map) Table 73. Texas Regional Entity Table...

  4. EIA - Petroleum & Other Liquids Data

    Gasoline and Diesel Fuel Update (EIA)

    and Renewable Fuel Tables (tables 73-120) Excel Gif Electric Power Projections for Electricity Market Module Regions (NERC Region Map) Table 73. Texas Regional Entity Excel...

  5. Structure determination of {alpha}-La{sub 6}W{sub 2}O{sub 15}

    SciTech Connect (OSTI)

    Chambrier, M-H., E-mail: marie-helene.chambier.etu@univ-lemans.f [Laboratoire des Oxydes et Fluorures, UMR-CNRS 6010, Universite du Maine, 72085 Le Mans Cedex 9 (France); Ibberson, R.M. [ISIS Facility, STFC-Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom); Goutenoire, F., E-mail: francois.goutenoire@univ-lemans.f [Laboratoire des Oxydes et Fluorures, UMR-CNRS 6010, Universite du Maine, 72085 Le Mans Cedex 9 (France)

    2010-06-15T23:59:59.000Z

    The structure of the high temperature alpha form of La{sub 6}W{sub 2}O{sub 15} has been determined ab-initio from high temperature laboratory X-ray and neutron time-of-flight data. This tungstate crystallizes in the non-centrosymmetric orthorhombic space group (No. 20) C222{sub 1}, with Z=2, a=12.6250(2) A, b=9.1875(1) A, c=5.9688(1) A. The structure comprises [O{sub 2}La{sub 3}] infinite ribbons and is better described by the structural formula [O{sub 2}La{sub 3}]{sub 2}[WO{sub 5.5}]{sub 2}. Using this description we can understand the strong structural similarity of the present compound with compounds of the general composition BiM{sub 2}AO{sub 6} (M=Cu, Mg, Zn, Mn, Cd, Ca, Pb; A=P, As, V) described as [O{sub 2}M{sub 2}Bi][AO{sub 4}]. The [WO{sub 5.5}] entity implies oxygen disorder in the material. - Graphical abstract: Projection of the polyhedra around the tungsten atom. Atoms labelled in grey are occupied at 50%. Short oxygen-oxygen distances are marked. The polyhedra represents WO{sub 5.5} that is related to the structural unit W{sub 2}O{sub 11} unit. Alpha-La{sub 6}W{sub 2}O{sub 15} could be described as [O{sub 2}La{sub 3}]{sub 2}[WO{sub 5.5}]{sub 2}.

  6. Measurement of the neutron F<sub>2sub> structure function via spectator tagging with CLAS

    SciTech Connect (OSTI)

    Baillie, N; Zhang, J; Bosted, P; Bultmann, S; Christy, M E; Fenker, H; Griffioen, K A; Keppel, C E; Kuhn, S E; Melnitchouk, W; Tvaskis, V; Adhikari, K P; Adikaram, D; Aghasyan, M; Amaryan, M J; Anghinolfini, M; Arrington, J; Avakian, H; Baghdasaryan, H; Battaglieri, M; Biselli, A A; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Cole, P L; Contalbrigo, M; Crede, V; D& #x27; Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Dey, B; Djalali, C; Dodge, G; Domingo, J; Doughty, D; Dupre, R; Dutta, D; Ent, R; Egiyan, H; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Fradi, A; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Gohn, W; Golovatch, E; Gothe, R W; Graham, L; Guegan, B; Guidal, M; Guler, N; Guo, L; Hafidi, K; Heddle, D; Hicks, K; Holtrop, M; Hungerford, E; Hyde, C E; Ilieva, Y; Ireland, D G; Ispiryan, M; Isupov, E L; Jawalkar, S S; Jo, H S; Kalantarians, N; Khandaker, M; Khetarpal, P; Kim, A; Kim, W; King, P M; Klein, A; Klein, F J; Klimenko, A; Kubarovsky, V; Kuleshov, S V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, I.J. D; Mao, Y; Markov, N; McKinnon, B; Mineeva, T; Morrison, B; Moutarde, H; Munevar, E; Nadel-Turonski, P; Ni, A; Niccolai, S; Niculescu, I; Niculescu, G; Osipenko, M; Ostrovidov, A I; Pappalardo, L; Park, K; Park, S; Pasyuk, E; Anefalos Pereira, S; Pisano, S; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Sharabian, Y G; Sober, D I; Sokhan, D; Stepanyan, S; Stepanyan, S S; Stoler, P; Strauch, S; Taiuti, M; Tang, W; Ungaro, M; Vineyard, M F; Voutier, E; Watts, D P; Weinstein, L B; Weygand, D P; Wood, M H; Zana, L

    2012-04-06T23:59:59.000Z

    We report on the first measurement of the F<sub>2sub> structure function of the neutron from semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ?< 100 MeV and their angles to ?> 100 degrees relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The F<sub>2sub>n data collected cover the nucleon resonance and deep-inelastic regions over a wide range of x for 0.65 < Q2 < 4.52 GeV2, with uncertainties from nuclear corrections estimated to be less than a few percent. These measurements provide the first determination of the neutron to proton structure function ratio F<sub>2sub>n/F>2sub>p at 0.2 ?< x ?< 0.8, essentially free of nuclear corrections.

  7. Directional drilling sub

    SciTech Connect (OSTI)

    Benoit, L.F.

    1980-09-02T23:59:59.000Z

    A directional drilling ''sub'' provides a shifting end portion which allows the sub to be rotated from a first in-line axially straight orientation with the drill string to a second angled or ''bent'' position which second position is normally associated with conventional bent ''subs'' which are permanently structured in the bent position. The device shifts from the first (In-line) position to the second (Bent) position upon the application of torsional force thereto which torsional force can be applied, for example, by the actuation of a ''turbodrill'' (Normally attached thereto in operation). The device can be manufactured or machined to provide varying angles to the sub in its bent position to satisfy differing directional drilling situations. The axially aligned first position allows easy entry of the drill string, sub , and turbodrill into the well hole, while the second bend position is used to commence directional drilling. The sub will return gradually to its original axially aligned position when the device is withdrawn from the wellhole, as such position is the path of minimum resistance for the withdrawing drill string and torsion is not present to hold the sub in the bent position.

  8. Magnetic phase transitions and entropy change in layered NdMn{sub 1.7}Cr{sub 0.3}Si{sub 2}

    SciTech Connect (OSTI)

    Md Din, M. F., E-mail: mfmd999@uowmail.edu.au; Dou, S. X. [Institute for Superconductivity and Electronic Materials, University of Wollongong, Wollongong, New South Wales 2522 (Australia); Wang, J. L. [Institute for Superconductivity and Electronic Materials, University of Wollongong, Wollongong, New South Wales 2522 (Australia); Bragg Institute, Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234 (Australia); Campbell, S. J. [School of Physical, Environmental, and Mathematical Sciences, The University of New South Wales, Canberra, The Australian Defence Force Academy, Australian Capital Territory 2600 (Australia); Studer, A. J.; Avdeev, M.; Kennedy, S. J. [Bragg Institute, Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234 (Australia); Gu, Q. F. [Australian Synchrotron, 800 Blackburn Rd, Clayton 3168 (Australia); Zeng, R. [Institute for Superconductivity and Electronic Materials, University of Wollongong, Wollongong, New South Wales 2522 (Australia); Solar Energy Technologies, School of Computing, Engineering and Mathematics, University of Western Sydney, Penrith, NSW 2751 (Australia)

    2014-01-27T23:59:59.000Z

    A giant magnetocaloric effect has been observed around the Curie temperature, T{sub C}???42?K, in NdMn{sub 1.7}Cr{sub 0.3}Si{sub 2} with no discernible thermal and magnetic hysteresis losses. Below 400?K, three magnetic phase transitions take place around 380?K, 320?K and 42?K. Detailed high resolution synchrotron and neutron powder diffraction (10–400?K) confirmed the magnetic transitions and phases as follows: T{sub N}{sup intra}???380?K denotes the transition from paramagnetism to intralayer antiferromagnetism (AFl), T{sub N}{sup inter}???320?K represents the transition from the AFl structure to the canted antiferromagnetic spin structure (AFmc), while T{sub C}???42?K denotes the first order magnetic transition from AFmc to canted ferromagnetism (Fmc?+?F(Nd)) due to ordering of the Mn and Nd sub-lattices. The maximum values of the magnetic entropy change and the adiabatic temperature change, around T{sub C} for a field change of 5?T are evaluated to be ??S{sub M}{sup max}???15.9?J kg{sup ?1} K{sup ?1} and ?T{sub ad}{sup max}???5?K, respectively. The first order magnetic transition associated with the low levels of hysteresis losses (thermal sub 1.7}Cr{sub 0.3}Si{sub 2} offers potential as a candidate for magnetic refrigerator applications in the temperature region below 45?K.

  9. Evaluating sub-national building-energy efficiency policy options under uncertainty: Efficient sensitivity testing of alternative climate, technolgical, and socioeconomic futures in a regional intergrated-assessment model.

    SciTech Connect (OSTI)

    Scott, Michael J.; Daly, Don S.; Zhou, Yuyu; Rice, Jennie S.; Patel, Pralit L.; McJeon, Haewon C.; Kyle, G. Page; Kim, Son H.; Eom, Jiyong; Clarke, Leon E.

    2014-05-01T23:59:59.000Z

    Improving the energy efficiency of the building stock, commercial equipment and household appliances can have a major impact on energy use, carbon emissions, and building services. Subnational regions such as U.S. states wish to increase their energy efficiency, reduce carbon emissions or adapt to climate change. Evaluating subnational policies to reduce energy use and emissions is difficult because of the uncertainties in socioeconomic factors, technology performance and cost, and energy and climate policies. Climate change may undercut such policies. Assessing these uncertainties can be a significant modeling and computation burden. As part of this uncertainty assessment, this paper demonstrates how a decision-focused sensitivity analysis strategy using fractional factorial methods can be applied to reveal the important drivers for detailed uncertainty analysis.

  10. The new Hg-rich barium indium mercurides BaIn{sub x}Hg{sub 7?x} (x=3.1) and BaIn{sub x}Hg{sub 11?x} (x=0–2.8)

    SciTech Connect (OSTI)

    Wendorff, Marco; Schwarz, Michael; Röhr, Caroline, E-mail: caroline@ruby.chemie.uni-freiburg.de

    2013-07-15T23:59:59.000Z

    The title compounds BaIn{sub x}Hg{sub 7?x} (x=3.1(1)) and BaIn{sub x}Hg{sub 11?x} (x=0–2.8) were synthesized from stoichiometric ratios of the elements in Ta crucibles. Their crystal structures have been determined using single crystal X-ray data. BaIn{sub x}Hg{sub 7?x} (x=3.1(1)) crystallizes in a new structure type (orthorhombic, oC16, space group Cmmm: a=512.02(1), b=1227.68(3), c=668.61(2) pm, Z=2, R1=0.0311). In the structure, the atoms of the three crystallographically different mixed In/Hg positions form planar nets of four-, six- and eight-membered rings. These nets are shifted against each other such that the four-membered rings form empty distorted cubes. The cubes are connected via common edges, corners and folded ladders, which are also found in BaIn{sub 2}/BaHg{sub 2} (KHg{sub 2} structure type) and BaIn (?-NaHg type). The Ba atoms are centered in the eight-membered rings and exhibit an overall coordination number of 20. The [BaM{sub 20}] polyhedra and twice as many distorted [M{sub 8}] cubes tesselate the space. BaIn{sub 2.8}Hg{sub 8.2} (cubic, cP36, space group Pm3{sup ¯}m, a=961.83(1) pm, Z=3, R1=0.0243) is the border compound of the phase width BaIn{sub x}Hg{sub 11?x} of the rare BaHg{sub 11} structure type. In the structure, ideal [M{sub 8}] cubes (at the corners of the unit cell) and BaM{sub 20} polyhedra (at the edges of the unit cell) represent the building blocks comparable to the other new In mercuride. In accordance with the increased In/Hg content, additional M-pure regions appear: the center of the unit cell contains a huge [Hg(1)M(2){sub 12}M(3,4){sub 32}] polyhedron, a Hg-centered cuboctahedron of In/Hg atoms surrounded by a capped cantellated cube of 32 additional M atoms. For both structure types, the bonding situation and the ‘coloring’, i.e. the In/Hg distribution of the polyanionic network, are discussed considering the different sizes of the atoms and the charge distribution (Bader AIM charges), which have been calculated within the framework of FP-LAPW density functional theory. - Graphical abstract: BaIn{sub 2.6}Hg{sub 4.4}: distorted cubes [(In/Hg){sub 8}] (green, like in BaHg{sub 11}), folded ladders (violet, like in BaIn, BaHg{sub 2} and BaIn{sub 2}) and Ba coordination polyhedra [Ba(In/Hg){sub 20}] (blue, like in BaHg{sub 11}). - Highlights: • The Hg-rich In-mercuride BaIn{sub 3.1}Hg{sub 3.9} crystallizes with a singular structure type. • The phase width of the BaHg{sub 11} structure in BaIn{sub x}Hg{sub 11-x} ends at x=2.8. • The relations of both compounds with other alkaline-earth mercurides are outlined. • The Hg/In coloring of the polyanion is discussed considering the structure features. • Bonding aspects are explored using band structure calculations.

  11. Inductively coupled plasma etching of Si{sub 1-x}Ge{sub x} in CF{sub 4}/Ar and Cl{sub 2}/Ar discharges

    SciTech Connect (OSTI)

    Wu, S.-L.; Lee, C.-H.; Chang, S.-J.; Lin, Y.-M. [Department of Electronics Engineering, Cheng Shiu University, 840 Chengcing Road, Niaosong, Kaohsiung 833, Taiwan (China); Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, 1 Ta Hseuh Road, Tainan 701, Taiwan (China); Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, 1 Ta Hseuh Road, Tainan 701, Taiwan (China)

    2006-05-15T23:59:59.000Z

    In this article, we report the experimental realization of SiGe/Si materials using CF{sub 4}/Ar and Cl{sub 2}/Ar mixed-gas inductively coupled plasma (ICP) etching process. The effects of process parameters such as gas combination and gas species on etch rates and selectivities were investigated. It was found that samples in CF{sub 4} gas result in a faster etching rate than those obtained in Cl{sub 2} gas, which are responsible for a lower boiling point for Si-based fluoride. The lower boiling point provides more chemically active Si and SiGe materials. Moreover, the selectivity of 1.5 between Si{sub 0.3}Ge{sub 0.7}/Si by ICP technology was found and higher than that obtained previously by reactive ion etching reported in the literature. Based on these etch characteristics, the application of the ICP process to the device fabrication of SiGe doped-channel field-effect transistors was conducted. The devices using ICP mesa have excellent pinch-off characteristics with relatively low leakage current, small output conduction in the saturated region, and low knee voltage.

  12. Characterization of nanosized Al{sub 2}(WO{sub 4}){sub 3}

    SciTech Connect (OSTI)

    Nihtianova, D., E-mail: diana.nihtianova@gmail.com [Institute of Mineralogy and Crystallography, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bl. 107, 1113 Sofia (Bulgaria); Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bl. 11, 1113 Sofia (Bulgaria); Velichkova, N., E-mail: veli4kov@svr.igic.bas.bg [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bl. 11, 1113 Sofia (Bulgaria); Nikolova, R., E-mail: rosica.pn@clmc.bas.bg [Institute of Mineralogy and Crystallography, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bl. 107, 1113 Sofia (Bulgaria); Koseva, I., E-mail: ikosseva@svr.igic.bas.bg [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bl. 11, 1113 Sofia (Bulgaria); Yordanova, A., E-mail: a.yordanova@svr.igic.bas.bg [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bl. 11, 1113 Sofia (Bulgaria); Nikolov, V., E-mail: vnikolov@svr.igic.bas.bg [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bl. 11, 1113 Sofia (Bulgaria)

    2011-11-15T23:59:59.000Z

    Graphical abstract: TEM method allows to detect small quantities of impurities not detectable by other methods. In our case impurities of W{sub 5}O{sub 14} are detected in Al{sub 2}(WO{sub 4}){sub 3} nanopowder. Highlights: {yields} Nanosized Al{sub 2}(WO{sub 4}){sub 3} by simple co-precipitation method. {yields} Spherical particles with mean size of 22 nm distributed between 10 and 40 nm at 630 {sup o}C. {yields} XRD, DTA and TEM confirm well defined products with perfect structure. {yields} TEM locality allows detection of impurities not detectable by XRD and DTA. -- Abstract: Nanosized aluminum tungstate Al{sub 2}(WO{sub 4}){sub 3} was prepared by co-precipitation reaction between Na{sub 2}WO{sub 4} and Al(NO{sub 3}){sub 3} aqueous solutions. The powder size and shape, as well as size distribution are estimated after different conditions of powder preparation. The purity of the final product was investigated by XRD and DTA analyses, using the single crystal powder as reference. Between the specimen and the reference no difference was detected. The crystal structure of Al{sub 2}(WO{sub 4}){sub 3} nanosized powder was confirmed by TEM (SAED, HRTEM). In additional, TEM locality allows to detect some W{sub 5}O{sub 14} impurities, which are not visible by conventional X-ray powder diffraction and thermal analyses.

  13. The polygallides: Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub2}.

    SciTech Connect (OSTI)

    Peter, S. C.; Malliakas, C. D.; Nakotte, H.; Kothapilli, K.; Rayaprol, S.; Schultz, A. J.; Kanatzidis, M. G. (Materials Science Division); ( XSD); (Northwestern Univ.); (Jawaharlal Nehru Centre for Adv. Sci. Res.); (New Mexico State Univ.); (Los Alamos Nat. Lab.); (UGC-DAE Consortium for Sci. Res.)

    2012-03-01T23:59:59.000Z

    Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} were obtained from reactions of Yb and Ge in excess liquid gallium. The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was refined using X-ray and neutron diffraction data on selected single crystals. Yb{sub 3}Ga{sub 7}Ge{sub 3} crystallizes in the monoclinic space group C2/c with lattice constants a = 12.2261(20) {angstrom}, b = 10.7447(20) {angstrom}, c = 8.4754(17) {angstrom} and {beta} = 110.288(30){sup o} (neutron diffraction data). The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} is an intergrowth of planar layers of YbGa{sub x}Ge{sub y} and puckered layers of (Ge)n. YbGa{sub 4}Ge{sub 2} crystallizes in a modified PuGa{sub 6} structure type in the tetragonal polar space group I4cm with lattice constants a = b = 5.9874(6) {angstrom} and c = 15.1178(19) {angstrom}. The structure of YbGa{sub 4}Ge{sub 2} is an intergrowth of puckered Ga layers and puckered Ga{sub x}Ge{sub y} layers with Yb atoms residing within the channels formed by the connection of the two layers. Physical properties, resistivity ({rho}), magnetic susceptibility ({chi}) and specific heat (C) were measured for Yb{sub 3}Ga{sub 7}Ge{sub 3}. No magnetic ordering was observed. It was found that at low temperatures, {rho} varied as T{sup 2} and C{alpha}T, indicating Fermi-liquid regime in Yb{sub 3}Ga{sub 7}Ge{sub 3} at low temperatures.

  14. Investigation on dielectric properties of atomic layer deposited Al{sub 2}O{sub 3} dielectric films

    SciTech Connect (OSTI)

    Y?ld?z, Dilber Esra [Department of Physics, Faculty of Arts and Sciences, Hitit University, Çorum 19030 (Turkey); Y?ld?r?m, Mert; Gökçen, Muharrem [Department of Physics, Faculty of Arts and Sciences, Düzce University, Düzce 81620 (Turkey)

    2014-05-15T23:59:59.000Z

    Al/Al{sub 2}O{sub 3}/p-Si Schottky barrier diodes (SBDs) were fabricated using atomic layer deposition technique in order to investigate dielectric properties of SBDs. For this purpose, admittance measurements were conducted at room temperature between ?1?V and 3?V in the frequency range of 10 kHz and 1?MHz. In addition to the investigation of Al{sub 2}O{sub 3} morphology using atomic force microscope, dielectric parameters; such as dielectric constant (??), dielectric loss (??), dielectric loss tangent (tan??), and real and imaginary parts of dielectric modulus (M? and M?, respectively), were calculated and effect of frequency on these parameters of Al/Al{sub 2}O{sub 3}/p-Si SBDs was discussed. Variations in these parameters at low frequencies were associated with the effect of interface states in low frequency region. Besides dielectric parameters, ac electrical conductivity of these SBDs was also investigated.

  15. Electrical and structural characteristics of metamorphic In{sub 0.38}Al{sub 0.62}As/In{sub 0.37}Ga{sub 0.63}As/In{sub 0.38}Al{sub 0.62}As HEMT nanoheterostructures

    SciTech Connect (OSTI)

    Galiev, G. B., E-mail: s_s_e_r_p@mail.ru; Klimov, E. A.; Klochkov, A. N.; Maltsev, P. P.; Pushkarev, S. S. [Russian Academy of Sciences, Institute of Ultrahigh Frequency Semiconductor Electronics (Russian Federation)] [Russian Academy of Sciences, Institute of Ultrahigh Frequency Semiconductor Electronics (Russian Federation); Zhigalina, O. M. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Imamov, R. M., E-mail: imamov@ns.crys.ras.ru [Russian Academy of Sciences, Institute of Ultrahigh Frequency Semiconductor Electronics (Russian Federation); Kuskova, A. N.; Khmelenin, D. N. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2013-11-15T23:59:59.000Z

    The influence of the metamorphic buffer design and epitaxial growth conditions on the electrical and structural characteristics of metamorphic In{sub 0.38}Al{sub 0.62}As/In{sub 0.37}Ga{sub 0.63}As/In{sub 0.38}Al{sub 0.62}As high electron mobility transistor (MHEMT) nanoheterostructures has been investigated. The samples were grown on GaAs(100) substrates by molecular beam epitaxy. The active regions of the nanoheterostructures are identical, while the metamorphic buffer In{sub x}Al{sub 1-x}As is formed with a linear or stepwise (by {Delta}{sub x} = 0.05) increase in the indium content over depth. It is found that MHEMT nanoheterostructures with a step metamorphic buffer have fewer defects and possess higher values of two-dimensional electron gas mobility at T = 77 K. The structures of the active region and metamorphic buffer have been thoroughly studied by transmission electron microscopy. It is shown that the relaxation of metamorphic buffer in the heterostructures under consideration is accompanied by the formation of structural defects of the following types: dislocations, microtwins, stacking faults, and wurtzite phase inclusions several nanometers in size.

  16. Structural characterization and novel optical properties of defect chalcopyrite ZnGa{sub 2}Te{sub 4} thin films

    SciTech Connect (OSTI)

    Fouad, S.S., E-mail: icgegypt@link.net [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Sakr, G.B., E-mail: gamalsaker@yahoo.com [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Yahia, I.S., E-mail: dr_isyahia@yahoo.com [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Basset, D.M. Abdel, E-mail: dalia.physics@gmail.com [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt)] [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt)

    2011-11-15T23:59:59.000Z

    Highlights: {yields} Preparation and characterization of ZnGa{sub 2}Te{sub 4} in powder and thin film forms. {yields} Structure properties such as XRD and EDX. {yields} Optical constant of the as-deposited ZnGa{sub 2}Te{sub 4} for the first time. {yields} Extraction of the optical parameters of the studied films. -- Abstract: Stoichiometric thin film samples of the ternary ZnGa{sub 2}Te{sub 4} defect chalcopyrite compound were prepared and characterized by X-ray diffraction technique. The elemental chemical composition of the prepared bulk material as well as of the as-deposited film was determined by energy-dispersive X-ray spectrometry. ZnGa{sub 2}Te{sub 4} thin films were deposited, by conventional thermal evaporation technique onto highly cleaned glass substrates. The X-ray and electron diffraction studies revealed that the as-deposited and the annealed ZnGa{sub 2}Te{sub 4} films at annealing temperature t{sub a} {<=} 548 K are amorphous, while those annealed at t{sub a} {>=} 573 K (for 1 h), are polycrystalline. The optical properties of the as-deposited films have been investigated for the first time at normal incidence in the spectral range from 500 to 2500 nm. The refractive index dispersion in the transmission and low absorption region is adequately described by the Wemple-DiDomenico single oscillator model, whereby, the values of the oscillator parameters have been calculated. The analysis of the optical absorption coefficient revealed an in-direct optical transition with energy of 1.33 eV for the as-deposited sample. This work suggested that ZnGa{sub 2}Te{sub 4} is a good candidate in solar cell devices as an absorbing layer.

  17. VO.sub.2 precipitates for self-protected optical surfaces

    DOE Patents [OSTI]

    Gea, Laurence A. (Knoxville, TN); Boatner, Lynn A. (Oak Ridge, TN)

    1999-01-01T23:59:59.000Z

    A method for forming crystallographically coherent precipitates of vanadium dioxide in the near-surface region of sapphire and the resulting product is disclosed. Ions of vanadium and oxygen are stoichiometrically implanted into a sapphire substrate (Al.sub.2 O.sub.3), and subsequently annealed to form vanadium dioxide precipitates in the substrate. The embedded VO.sub.2 precipitates, which are three-dimensionally oriented with respect to the crystal axes of the Al.sub.2 O.sub.3 host lattice, undergo a first-order monoclinic-to-tetragonal (and also semiconducting-to-metallic) phase transition at .about.77.degree. C. This transformation is accompanied by a significant variation in the optical transmission of the implanted region and results in the formation of an optically active, thermally "switchable" surface region on Al.sub.2 O.sub.3.

  18. Low temperature hopping in granular oxides La{sub 0.67}Ca{sub 0.33}MnO{sub 3} and La{sub 0.5}Sr{sub 0.5}CoO{sub 3}

    SciTech Connect (OSTI)

    Narjis, A., E-mail: kaaouachi21@yahoo.fr; Kaaouachi, A. El, E-mail: kaaouachi21@yahoo.fr; Tata, O. [Research Group, Equipe de Semiconducteurs, de Nanotechnologie et de Programmation Scientifique, Physics department, Ibn Zohr University, Faculty of Sciences, B.P 8106, Hay Dakhla, 80000 Agadir (Morocco); Liang, C.-T. [School of Electronic and Electrical Engineering Sungkyunkwan University, Sunwon 440-746, Korea and Department of Physics, National Taiwan University, Taipei, Taiwan (China); Idrissi, H. El; Zatni, A. [Laboratoire Electronique, Électrotechnique, Automatique et Traitement de l'Information (EEA TI). Département Génie Electrique Université Hassan II Mohammedia Casablanca, Faculté des Sciences et Techniques de Mohamme (Morocco)

    2014-01-27T23:59:59.000Z

    We studied electrical transport in La{sub 0.67}Sr{sub 0.33}MnO{sub 3} (LCMO) and La{sub 0.5}Sr{sub 0.5}CoO{sub 3} (LSCO) nanocrystals over a temperature range of 0.4 K ? T ? 5 K. In both samples, two distinct behaviors of the conductivity are observed. For T>1 K, the variable range hopping regime is observed in LCMO sample with enhancement of the relative permittivity. In contrast, this behavior is not consistent with the extracted parameters in LSCO sample. For T<1 K, the transport is believed to occur through the metallic droplets connected to the intergranular regions where the negative magnetoresistance is due to spin-polarized tunneling phenomenon.

  19. Measurement of the ratio of the production cross sections times branching fractions of B<sub>c>± ? J/??±and B± ? J/? K± and B(B<sub>c>±? J/? ?±?±?-/+)/B(B<sub>c>± ? J/? ?±) in pp collisions at ?s = 7 TeV

    SciTech Connect (OSTI)

    Khachatryan, V. [Yerevan Physics Institute (Armenia); et al.,

    2015-01-01T23:59:59.000Z

    The ratio of the production cross sections times branching fractions (?(B<sub>c>±) B(B<sub>c>± ? J/??±))/(?(B±) B(B± ? J/?K±) is studied in proton-proton collisions at a center-of-mass energy of 7 TeV with the CMS detector at the LHC. The kinematic region investigated requires Ba,sub>c>± and B±mesons with transverse momentum p? > 15 GeV and rapidity |y| < 1.6. The data sample corresponds to an integrated luminosity of 5.1 fb-1. The ratio is determined to be [0.48 ± 0.05 (stat) ± 0.03(syst) ± 0.05 (?B<sub>c>)]% The J/??±?±?-/+ decay mode is also observed in the same data sample. Using a model-independent method developed to measure the efficiency given the presence of resonant behaviour in the three-pion system, the ratio of the branching fractions J/? ?±?±?-/+)/B(B<sub>c>± is measured to be 2.55 ± 0.80(stat) ± 0.33(syst) +0.04<sub>-0.01sub> (?B<sub>c>), consistent with the previous LHCb result.

  20. Magnetic depth profile of a modulation doped La{sub 1-x}Ca{sub x}MnO{sub 3} exchange-biased system.

    SciTech Connect (OSTI)

    Hoffmann, A.; May, S. J.; teVelthuis, S. G. E.; Park, S.; Fitzsimmons, M. R.; Campillo, G.; Gomez, M. E.; LANL; Pusan National Univ.; Universidad del Valle; Universidad Autonoma de Madrid

    2009-01-01T23:59:59.000Z

    Recent magnetometry measurements in modulation-doped La{sub 1-x}Ca{sub x}MnO{sub 3} suggested that a net magnetization extends from the ferromagnetic layers into the adjacent antiferromagnet layers. Here we test this hypothesis by polarized neutron reflectometry, which allows us to determine the depth resolved magnetization profile. From fits to the reflectivity data we find that the additional magnetization does not occur at the ferromagnetic/antiferromagnetic interfaces, but rather in a thin region of the first antiferromagnetic layer adjacent to the interface with the substrate.

  1. Structural distortions in the spin-gap regime of the quantum antiferromagnet SrCu{sub 2}(BO{sub 3}){sub 2}

    SciTech Connect (OSTI)

    Vecchini, C., E-mail: c.vecchini@rl.ac.u [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Vassilika Vouton, 711 10 Heraklion, Crete (Greece); ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Adamopoulos, O. [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Vassilika Vouton, 711 10 Heraklion, Crete (Greece); Department of Chemistry, University of Crete, Voutes, 710 03 Heraklion (Greece); Chapon, L.C. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Lappas, A., E-mail: lappas@iesl.forth.g [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Vassilika Vouton, 711 10 Heraklion, Crete (Greece); Kageyama, H. [Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Ueda, Y. [Institute of Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Zorko, A. [Institute Jozef Stefan, Jamova 39, 1000 Ljubljana (Slovenia)

    2009-12-15T23:59:59.000Z

    We report the first crystallographic study within the low-temperature (<40 K) spin-gap region of the two-dimensional frustrated antiferromagnet SrCu{sub 2}(BO{sub 3}){sub 2}. The crystal system does not deviate from the tetragonal I-42m space group symmetry. However, our high-resolution neutron powder diffraction measurements uncover subtle structural modifications below 34 K, concomitant to the formation of the dimer singlet ground state. Intimate spin-lattice coupling leads to negative thermal expansion of the tetragonal structure, which reflects into particular local lattice adjustments. The extracted structural parameters suggest the reduction of the buckling found in the copper-borate planes and the strengthening of the leading, in-plane intra-dimer superexchange interaction. The observed contraction along the c-axis, associated with the inter-dimer exchange in adjacent layers, indicates the involvement of weaker three-dimensional interactions in the magnetic properties. The rules posed by the crystal symmetry do not preclude Dzyaloshinsky-Moriya interactions, which therefore remain as an important source of spin anisotropy necessary to rationalise the ground state behaviour. - Abstract: We report the first crystallographic study within the low-temperature spin-gap region of the two-dimensional frustrated antiferromagnet SrCu{sub 2}(BO{sub 3}){sub 2}. Subtle spin-lattice coupling was unveiled in the low-temperature region. Display Omitted

  2. The polygallides: Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2}

    SciTech Connect (OSTI)

    Peter, Sebastian C. [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064 (India); Malliakas, Christos D. [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); Nakotte, Heinze; Kothapilli, Karunakar [Physics Department, New Mexico State University, Las Cruces, NM 88003 (United States); Los Alamos Neutron Science Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Rayaprol, Sudhindra [UGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC, R-5 Shed, Trombay, Mumbai 400085 (India); Schultz, Arthur J. [X-Ray Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Kanatzidis, Mercouri G., E-mail: m-kanatzidis@northwestern.edu [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2012-03-15T23:59:59.000Z

    Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} were obtained from reactions of Yb and Ge in excess liquid gallium. The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was refined using X-ray and neutron diffraction data on selected single crystals. Yb{sub 3}Ga{sub 7}Ge{sub 3} crystallizes in the monoclinic space group C2/c with lattice constants a=12.2261(20) Angstrom-Sign , b=10.7447(20) Angstrom-Sign , c=8.4754(17) Angstrom-Sign and {beta}=110.288(30) Degree-Sign (neutron diffraction data). The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} is an intergrowth of planar layers of YbGa{sub x}Ge{sub y} and puckered layers of (Ge){sub n}. YbGa{sub 4}Ge{sub 2} crystallizes in a modified PuGa{sub 6} structure type in the tetragonal polar space group I4cm with lattice constants a=b=5.9874(6) Angstrom-Sign and c=15.1178(19) Angstrom-Sign . The structure of YbGa{sub 4}Ge{sub 2} is an intergrowth of puckered Ga layers and puckered Ga{sub x}Ge{sub y} layers with Yb atoms residing within the channels formed by the connection of the two layers. Physical properties, resistivity ({rho}), magnetic susceptibility ({chi}) and specific heat (C) were measured for Yb{sub 3}Ga{sub 7}Ge{sub 3}. No magnetic ordering was observed. It was found that at low temperatures, {rho} varied as T{sup 2} and C{proportional_to}T, indicating Fermi-liquid regime in Yb{sub 3}Ga{sub 7}Ge{sub 3} at low temperatures. - Graphical abstract: The compounds Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} are obtained from reactions of Yb and Ge in excess liquid gallium. Highlights: Black-Right-Pointing-Pointer Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} are two new polygallides. Black-Right-Pointing-Pointer The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was established using neutron diffraction data. Black-Right-Pointing-Pointer YbGa{sub 4}Ge{sub 2} is one of the rare polar intermetallic compounds. Black-Right-Pointing-Pointer The physical properties of Yb{sub 3}Ga{sub 7}Ge{sub 3} point to a Fermi-liquid regime at low temperature.

  3. Observation of ?<sub>cJ> decays to ??¯¯¯????

    SciTech Connect (OSTI)

    Ablikim, M.; Achasov, M. N.; Ambrose, D. J.; An, F. F.; An, Q.; An, Z. H.; Bai, J. Z.; Ban, Y.; Becker, J.; Bennett, J. V.; Bertani, M.; Bian, J. M.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; Ding, W. M.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fang, J.; Fang, S. S.; Fava, L.; Feldbauer, F.; Feng, C. Q.; Ferroli, R. B.; Fu, C. D.; Fu, J. L.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y. P.; Han, Y. L.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, H. M.; Hu, J. F.; Hu, T.; Huang, G. M.; Huang, J. S.; Huang, X. T.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, X. B.; Ji, X. L.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Kuehn, W.; Lai, W.; Lange, J. S.; Li, C. H.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, K.; Li, Lei; Li, Q. J.; Li, S. L.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Liao, X. T.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, C. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H.; Liu, H. B.; Liu, H. H.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K. Y.; Liu, Kai; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. H.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X. Y.; Ma, Y.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Morales Morales, C.; Motzko, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nicholson, C.; Nikolaev, I. B.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Park, J. W.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Prencipe, E.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, X. S.; Qin, Y.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schaefer, B. D.; Schulze, J.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Toth, D.; Ullrich, M.; Varner, G. S.; Wang, B.; Wang, B. Q.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q.; Wang, Q. J.; Wang, S. G.; Wang, X. L.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Weidenkaff, P.; Wen, Q. G.; Wen, S. P.; Werner, M.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, S. X.; Wu, W.; Wu, Z.; Xia, L. G.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, G. M.; Xu, H.; Xu, Q. J.; Xu, X. P.; Xu, Z. R.; Xue, F.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yu, S. P.; Yuan, C. Z.; Yuan, Y.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, S. H.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. S.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, J. W.; Zhao, K. X.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, S. J.; Zhao, T. C.; Zhao, X. H.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zhong, B.; Zhong, J.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, X. W.; Zhu, Y. C.; Zhu, Y. M.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.

    2012-09-01T23:59:59.000Z

    Decays of the ?<sub>cJ> states (J=0, 1, 2) to ??¯¯¯????, including processes with intermediate ?(1385), are studied through the E1 transition ?'???<sub>cJ> using 106×10? ?' events collected with the BESIII detector at BEPCII. This is the first observation of ?cJ decays to the final state ??¯¯¯????. The branching ratio of the intermediate process ?<sub>cJ>??(1385)±?¯¯¯(1385)? is also measured for the first time, and the results agree with the theoretical predictions based on the color-octet effect.

  4. Energy Efficiency in Western Utility Resource Plans: Impacts onRegional Resources Assessment and Support for WGA Policies

    SciTech Connect (OSTI)

    Hopper, Nicole; Goldman, Charles; Schlegal, Jeff

    2006-08-01T23:59:59.000Z

    In the aftermath of the consumer price shocks and short-term power shortages of the 2000-01 electricity crisis, policymakers and regulators in Western states are placing increased emphasis on integrated resource planning (IRP), resource adequacy and assessment and a diversified portfolio of resources to meet the needs of electricity consumers. In some states, this has led to a resurgence in state and utility commitments to energy efficiency. Increasing interest in acquiring energy efficiency as a power-system resource is also driven by the desire to dampen high growth rates in electricity demand in some Western states, rapid increases in natural gas prices, concerns about the environmental impacts of electricity generation (e.g. water consumption by power plants, air quality), and the potential of energy efficiency to provide utility bill savings for households and businesses (WGA CDEAC 2006). Recognizing the cost-competitiveness and environmental benefits of energy efficiency, the Western Governor's Association (WGA) has set a high priority for energy efficiency, establishing a goal of reducing projected electricity demand by 20% across the West by 2020 in a policy resolution on Clean and Diversified Energy for the West (WGA 2004). Nationally, the need for improved tracking of demand-side resources in load forecasting is formalized in the North American Electric Reliability Council (NERC)'s recently adopted reliability standards, which utilities and regional reliability organizations will need to comply with (NERC 2005a and 2005b). In this study, we examine the treatment of energy efficiency in recent resource plans issued by fourteen investor-owned utilities (IOUs) in the Western United States and Canada. The goals of this study are to: (1) summarize energy-efficiency resources as represented in a large sample of recent resource plans prepared by Western utilities and identify key issues; (2) evaluate the extent to which the information provided in current resource plans can be used to support region-wide resource assessment and tracking of state/utility progress in meeting the WGA's energy-efficiency goals (WGA 2004); and (3) offer recommendations on information and documentation of energy-efficiency resources that should be included in future resource plans to facilitate comparative review and regional coordination. The scope of this report covers projected electric end-use efficiency investments reported in all Western utility resource plans that were publicly available as of February 2006. While a few utilities included additional demand-side resources, such as demand response, in their plans, we do not report that information. However, many of the issues and recommendations in reference to energy efficiency in this report are relevant to other demand-side resources as well. This report is organized as follows. Section 2 outlines the data sources and approach used in this study and conceptualizes methods and metrics for tracking energy-efficiency resources over time. Section 3 presents results from the review of the utility resource plans. Important issues encountered in reviewing the resource plans are discussed in section 4. Finally, section 5 concludes with recommendations for improving the tracking and reporting of energy efficiency in forthcoming resource plans.

  5. Anisotropic magnetoresistance of epitaxial Pr{sub 0.5}Sr{sub 0.5}MnO{sub 3} film

    SciTech Connect (OSTI)

    Chen, X. G.; Yang, Y. B.; Wang, C. S.; Liu, S. Q.; Zhang, Y.; Han, J. Z.; Yang, Y. C. [State Key Laboratory of Mesoscopic Physics, and School of Physics, Peking University, Beijing 100871 (China); Yang, J. B., E-mail: jbyang@pku.edu.cn [State Key Laboratory of Mesoscopic Physics, and School of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China)

    2014-01-28T23:59:59.000Z

    The magnetic field and temperature dependent anisotropic magnetoresistance (AMR) of the epitaxial grown Pr{sub 0.5}Sr{sub 0.5}MnO{sub 3} thin films was investigated. It was found that the magnetoresistance exhibited the characteristics of magnetic polaron hopping. A two-fold symmetric AMR occurred in the ferromagnetic region (?220?K?region (T?region.

  6. As[sub 2]S[sub 3]/Sr(Ti[sub 0.7]Co[sub 0.3])O[sub 3] and As[sub 2]S[sub 3]/Sr(Ti[sub 0.6]Fe[sub 0.4])O[sub 3] strip-loaded waveguides for integrated magneto-optical isolator applications

    E-Print Network [OSTI]

    Bi, Lei

    Sr(Ti[sub 0.6]Fe[sub 0.4])O[sub 3] (STF) and Sr(Ti[sub 0.7]Co[sub 0.3])O[sub 3] (STC) room-temperature ferromagnetic oxides were grown epitaxially on LaAlO[sub 3](001), (LaSr)(AlTa)O[sub 3] (001) and Si (001) substrates. ...

  7. Metal-semiconductor-transition observed in Bi{sub 2}Ca(Sr, Ba){sub 2}Co{sub 2}O{sub 8+?} single crystals

    SciTech Connect (OSTI)

    Dong, Song-Tao [National Laboratory of Solid State Microstructures and Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China); Institute of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Zhang, Bin-Bin; Zhang, Lun-Yong; Yao, Shu-Hua, E-mail: ybchen@nju.edu.cn, E-mail: shyao@nju.edu.cn; Zhou, Jian; Zhang, Shan-Tao; Gu, Zheng-Bin; Chen, Yan-Feng [National Laboratory of Solid State Microstructures and Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China); Chen, Y. B., E-mail: ybchen@nju.edu.cn, E-mail: shyao@nju.edu.cn [National Laboratory of Solid State Microstructures and Department of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China)

    2014-07-28T23:59:59.000Z

    Electrical property evolution of Bi{sub 2}AE{sub 2}Co{sub 2}O{sub 8+?} single crystals (AE?=?Ca, Sr and Ba) is systematically explored. When AE changes from Ca to Ba, the electrical property of Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+?} and Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} demonstrates semiconductor-like properties. But Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} shows the metallic behavior. Analysis of temperature-dependent resistance substantiates that from metallic Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} to semiconductor-like Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} can be attributed to Anderson localization. However the semiconductor behaviour of Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} and Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+?} is related to electronic correlations effect that is inferred by large negative magnetoresistance (?70%). The theoretical electronic structures and valence X-ray photoemission spectroscopy substantiate that there is a relative large density of state around Fermi level in Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} compared with other two compounds. It suggests that Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} is more apt to be metal in this material system.

  8. Enhancement of methanol electrocatalytic oxidation on platinized WO{sub 3}–TiO{sub 2} composite electrode under visible light irradiation

    SciTech Connect (OSTI)

    Wang, Caiqin [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China); Jiang, Fengxing [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013 (China); Zhou, Rong [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China); Du, Yukou, E-mail: duyk@suda.edu.cn [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China); Yang, Ping [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Wang, Chuanyi, E-mail: cywang@ms.xjb.ac.cn [Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China); Xu, Jingkun, E-mail: xujingkun@tsinghua.org.cn [Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013 (China)

    2013-03-15T23:59:59.000Z

    Highlights: ? A ternary composite catalyst of Pt–WO{sub 3}–TiO{sub 2} has been synthesized. ? The introduction of WO{sub 3} extends its absorption edge to visible light region. ? The electrode displays high electrocatalytic activity. ? With visible light irradiation, its electrocatalytic activity increases 70%. - Abstract: A ternary composite catalyst of Pt–WO{sub 3}–TiO{sub 2} has been successfully prepared by a chemical method. The prepared composite was systematically characterized by UV–vis diffuse reflectance absorption spectra (DRS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). The electrocatalytic properties of Pt–WO{sub 3}–TiO{sub 2} for methanol oxidation in an alkaline medium were evaluated by the cyclic voltammetry (CV) and chronoamperometry (CA) with or without visible light irradiation. Compared with the pure TiO{sub 2}, the introduction of WO{sub 3} extends its absorption edge to visible light region. Under visible light illumination, the Pt–WO{sub 3}–TiO{sub 2} composite catalyst exhibits higher electrocatalytic activity toward methanol oxidation in comparison with its counterpart, the pure Pt–TiO{sub 2} catalyst.

  9. Kinetics of SH with NO/sub 2/, O/sub 3/, O/sub 2/, and H/sub 2/O/sub 2/

    SciTech Connect (OSTI)

    Friedl, R.R.; Brune, W.H.; Anderson, J.G.

    1985-12-05T23:59:59.000Z

    A low pressure (1-8 torr of He) discharge flow reactor with (a) LIF detection of SH using a high repetition rate (20 kHz) metal atom laser to circumvent severe predissociation of the A/sup 2/..sigma../sup +/ state and (b) resonance fluorescence detection of OH has been used to examine the kinetics of the title reactions at 298 K: SH + NO/sub 2/ ..-->.. HSO + NO, SH + O/sub 3/ ..-->.. HSO + O/sub 2/; SH + O/sub 2/ ..-->.. SO + OH, SH + H/sub 2/O/sub 2/ ..-->.. H/sub 2/S + HO/sub 2/; SH + H/sub 2/O/sub 2/ ..-->.. HSO + H/sub 2/O. Regeneration of SH in reaction 2 by HSO + O/sub 3/ is observed and is used to infer a rate constant for HSO + O/sub 3/ ..-->.. products. Absence of OH production in that reaction implies that the primary products are SH + 2O/sub 2/. Isotope experiments with H/sub 2/S replaced by D/sub 2/S substantiate that conclusion and yield a reaction rate constant for DSO + O/sub 3/ ..-->.. SD + 2O/sub 2/. Brief discussions of SH reactivity compared with OH and Br are offered, as well as a summary of the atmospheric chemistry of SH. 20 references, 7 figures.

  10. High temperature redox reactions with uranium: Synthesis and characterization of Cs(UO{sub 2})Cl(SeO{sub 3}), Rb{sub 2}(UO{sub 2}){sub 3}O{sub 2}(SeO{sub 3}){sub 2}, and RbNa{sub 5}U{sub 2}(SO{sub 4}){sub 7}

    SciTech Connect (OSTI)

    Babo, Jean-Marie [Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390 (United States); Department of Civil and Environmental Engineering and Earth Sciences and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States); Albrecht-Schmitt, Thomas E., E-mail: talbrechtschmitt@gmail.com [Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390 (United States)

    2013-10-15T23:59:59.000Z

    Cs(UO{sub 2})Cl(SeO{sub 3}) (1), Rb{sub 2}(UO{sub 2}){sub 3}O{sub 2}(SeO{sub 3}){sub 3} (2), and RbNa{sub 5}U{sub 2}(SO{sub 4}){sub 7} (3) single crystals were synthesized using CsCl, RbCl, and a CuCl/NaCl eutectic mixture as fluxes, respectively. Their lattice parameters and space groups are as follows: P2{sub 1}/n (a=6.548(1) Å, b=11.052(2) Å, c=10.666(2) Å and ?=93.897(3)°), P1{sup ¯} (a=7.051(2) Å, b=7.198(2) Å, c=8.314(2) Å, ?=107.897(3)°, ?=102.687(3)° and ?=100.564(3)°) and C2/c (a=17.862(4) Å, b=6.931(1) Å, c=20.133(4) Å and ?=109.737(6)°. The small anionic building units found in these compounds are SeO{sub 3}{sup 2?} and SO{sub 4}{sup 2?} tetrahedra, oxide, and chloride. The crystal structure of the first compound is composed of [(UO{sub 2}){sub 2}Cl{sub 2}(SeO{sub 3}){sub 2}]{sup 2?} chains separated by Cs{sup +} cations. The structure of (2) is constructed from [(UO{sub 2}){sub 3}O{sub 11}]{sup 16?} chains further connected through selenite units into layers stacked perpendicularly to the [0 1 0] direction, with Rb{sup +} cations intercalating between them. The structure of compound (3) is made of uranyl sulfate layers formed by edge and vertex connections between dimeric [U{sub 2}O{sub 16}] and [SO{sub 4}] polyhedra. These layers contain unusual sulfate–metal connectivity as well as large voids. - Graphical abstract: A new family of uranyl selenites and sulfates has been prepared by high-temperature redox reactions. This compounds display new bonding motifs. Display Omitted - Highlights: • Low-dimensional Uranyl Oxoanion compounds. • Conversion of U(IV) to U(VI) at high temperatures. • Dimensional reduction by both halides and stereochemically active lone-pairs.

  11. Electronic and thermoelectric analysis of phases in the In<sub>2sub>O>3sub>(ZnO)k> system

    SciTech Connect (OSTI)

    Hopper, E. Mitchell; Zhu, Qimin; Song, Jung-Hwan; Peng, Haowei; Freeman, Arthur J.; Mason, Thomas O.

    2011-01-13T23:59:59.000Z

    The high-temperature electrical conductivity and thermopower of several compounds in the In<sub>2sub>O>3sub>(ZnO)k> system (k = 3, 5, 7, and 9) were measured, and the band structures of the k = 1, 2, and 3 structures were predicted based on first-principles calculations. These phases exhibit highly dispersed conduction bands consistent with transparent conducting oxide behavior. Jonker plots (Seebeck coefficient vs. natural logarithm of conductivity) were used to obtain the product of the density of states and mobility for these phases, which were related to the maximum achievable power factor (thermopower squared times conductivity) for each phase by Ioffe analysis (maximum power factor vs. Jonker plot intercept). With the exception of the k = 9 phase, all other phases were found to have maximum predicted power factors comparable to other thermoelectric oxides if suitably doped.

  12. Quantum Critical Transition Amplifies Magnetoelastic Coupling in Mn[N(CN)<sub>2sub>]>2sub>

    SciTech Connect (OSTI)

    Brinzari, T. V.; Chen, P.; Sun, Q.-C.; Liu, J.; Tung, L.-C.; Wang, Y.; Schlueter, J. A.; Singleton, J.; Manson, J. L.; Whangbo, M.-H.; Litvinchuk, A. P.; Musfeldt, J. L.

    2013-06-01T23:59:59.000Z

    We report the discovery of a magnetic quantum critical transition in Mn[N(CN)<sub>2sub>]>2sub> that drives the system from a canted antiferromagnetic state to the fully polarized state with amplified magnetoelastic coupling as an intrinsic part of the process. The local lattice distortions, revealed through systematic phonon frequency shifts, suggest a combined MnN<sub>6sub> octahedra distortion+counterrotation mechanism that reduces antiferromagnetic interactions and acts to accommodate the field-induced state. These findings deepen our understanding of magnetoelastic coupling near a magnetic quantum critical point and away from the static limit.

  13. Resonance Raman and theoretical investigation of the photodissociation dynamics of benzamide in S{sub 3} state

    SciTech Connect (OSTI)

    Pei Kemei; Ma Yufang; Zheng Xuming [Department of Chemistry and State Key Laboratory of ATMMT (MOE), Zhejiang Sci-Tech University, Hangzhou 310018 (China)

    2008-06-14T23:59:59.000Z

    Resonance Raman spectra were obtained for benzamide in methanol and acetonitrile solutions with excitation wavelengths in resonance with the S{sub 3} state. These spectra indicate that the Franck-Condon region photodissociation dynamics have multidimensional character with the motions mainly along the benzene ring C=C stretch {nu}{sub 9}, the Ph-CO-NH{sub 2} and ring benzene stretch {nu}{sub 14}, the CCH in plane bend {nu}{sub 17}, the Ph-CO-NH{sub 2} stretch and NH{sub 2} rock {nu}{sub 19}, the ring trigonal bend {nu}{sub 23}, and the ring deformation and Ph-CO-NH{sub 2} stretch {nu}{sub 29}. A preliminary resonance Raman intensity analysis was done, and the results were compared to those previously reported for acetophenone to examine the substituent effect. Solvent effect on the short-time photodissociation dynamics of benzamide was also examined. A conical intersection point S{sub 2}/S{sub 3} between S{sub 3} and S{sub 2} potential energy surfaces of benzamide was determined by using a complete active space self-consistent field theory computations. The structural differences and similarities between S{sub 3}/S{sub 2} point and S{sub 0} were examined, and the results were used to correlate to the Franck-Condon photodissociation dynamics of benzamide in S{sub 3} state.

  14. Microstructural features and domain formation in (Ba,Sr){sub 2}TiSi{sub 2}O{sub 8} fresnoites

    SciTech Connect (OSTI)

    Wong, Chui Ling, E-mail: wong0233@e.ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Ferraris, Cristiano [Laboratoire de Mineralogie et Cosmchimie du Museum National d'Historie Naturelle, UMR-CNRS 7202, CP 52, 61 Rue Buffon, 75005 Paris (France); White, T.J. [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Centre for Advanced Microscopy, The Australian National University, Canberra ACT 0200 (Australia)

    2011-07-15T23:59:59.000Z

    The formation and co-existence of crystallographically modulated and non-modulated regions in (Ba,Sr){sub 2}TiSi{sub 2}O{sub 8} fresnoites is reviewed, particularly the dependence on local composition. It is shown that perturbations of the average fresnoite structure, determined from appreciable single crystals, are in some cases better described as nanometric domain intergrowths where departures from ideal stoichiometry are characteristics of incommensuration, while modulation is absent from volumes that are less perturbed chemically. Evidence for this differentiation is obtained from selected area electron diffraction (SAED) patterns and high-resolution transmission electron microscopy (HRTEM) images. The domains are readily distinguished by their unique contrast in bright field electron micrographs. Fourier reconstructions of HRTEM images collected from areas with darker contrast show that modulation can change within relatively small volumes. Nearby areas with lighter contrast were found by SAED to be free of structural disorder and incommensurate reflections. - Graphical abstract: Fresnoite layers contain SiO{sub 4} and TiO{sub 5} polyhedra that undergo run rotation and tilting to create 3D, 4D and 5D structural modulations that can be directly observed by electron diffraction and high resolution imaging. Highlights: {yields}(Ba,Sr){sub 2}TiSi{sub 2}O{sub 8} fresnoites contain commensurate and incommensurate domains. > Departures in stoichiometry promote the formation of nanostructured domains. > Domains formation may provide a means for reducing strain in single crystals.

  15. Reverse Monte Carlo simulation of Se{sub 80}Te{sub 20} and Se{sub 80}Te{sub 15}Sb{sub 5} glasses

    SciTech Connect (OSTI)

    Abdel-Baset, A. M.; Rashad, M. [Physics Department, Faculty of Science , Assiut University, Assiut, P.O. Box 71516 (Egypt); Moharram, A. H. [Faculty of Science, King Abdul Aziz Univ., Rabigh Branch, P.O. Box 433 (Saudi Arabia)

    2013-12-16T23:59:59.000Z

    Two-dimensional Monte Carlo of the total pair distribution functions g(r) is determined for Se{sub 80}Te{sub 20} and Se{sub 80}Te{sub 15}Sb{sub 5} alloys, and then it used to assemble the three-dimensional atomic configurations using the reverse Monte Carlo simulation. The partial pair distribution functions g{sub ij}(r) indicate that the basic structure unit in the Se{sub 80}Te{sub 15}Sb{sub 5} glass is di-antimony tri-selenide units connected together through Se-Se and Se-Te chain. The structure of Se{sub 80}Te{sub 20} alloys is a chain of Se-Te and Se-Se in addition to some rings of Se atoms.

  16. Sr{sub 3}Al{sub 2}O{sub 5}Cl{sub 2}:Ce{sup 3+},Eu{sup 2+}: A potential tunable yellow-to-white-emitting phosphor for ultraviolet light emitting diodes

    SciTech Connect (OSTI)

    Song Yanhua; Jia Guang; Yang Mei; Huang Yeju; You Hongpeng; Zhang Hongjie [State Key laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China) and Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China)

    2009-03-02T23:59:59.000Z

    The Sr{sub 3}Al{sub 2}O{sub 5}Cl{sub 2}:Ce{sup 3+},Eu{sup 2+} phosphors were prepared by solid state reaction. The obtained phosphors exhibit a strong absorption in the UV-visible region and have two intense emission bands at 444 and 609 nm. The energy transfer from the Ce{sup 3+} to Eu{sup 2+} ions was observed, and the critical distance has been estimated to be about 24.5 A by spectral overlap method. Furthermore, the developed phosphors can generate lights from yellow-to-white region under the excitation of UV radiation by appropriately tuning the activator content, indicating that they have potential applications as an UV-convertible phosphor for white light emitting diodes.

  17. Lasing characteristics of ZrO{sub 2}–Y{sub 2}O{sub 3}–Ho{sub 2}O{sub 3} crystal

    SciTech Connect (OSTI)

    Borik, M A; Lomonova, E E; Kulebyakin, A V; Ushakov, S N [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Lyapin, A A; Ryabochkina, P A; Chabushkin, A N [N.P. Ogarev Mordovian State University, Saransk (Russian Federation)

    2013-09-30T23:59:59.000Z

    The spectral dependences of the gain cross section of the {sup 5}I{sub 8} ? {sup 5}I{sub 7}, {sup 5}I{sub 7} ? {sup 5}I{sub 8} transition of Ho{sup 3+} ions in the ZrO{sub 2} – 13.6 mol % Y{sub 2}O{sub 3} – 0.4 mol % Ho{sub 2}O{sub 3} crystal are calculated at different relative population inversions using the absorption and luminescence spectra of the {sup 5}I{sub 8} ? {sup 5}I{sub 7} and {sup 5}I{sub 7} ? {sup 5}I{sub 8} transitions of Ho{sup 3+} ions at T=''300'' K. Lasing of these crystals at the {sup 5}I{sub 7} ? {sup 5}I{sub 8} transition is obtained for the first time under pumping by a Tm : YLiF{sub 4} laser (?{sub p} = 1.905 ?m). The lasing wavelength is 2.17 ?m. (lasers)

  18. Dopant spin states and magnetism of Sn{sub 1?x}Fe{sub x}O{sub 2} nanoparticles

    SciTech Connect (OSTI)

    Punnoose, A., E-mail: apunnoos@boisestate.edu; Dodge, Kelsey; Reddy, K. M.; Franco, Nevil; Chess, Jordan; Eixenberger, Josh [Department of Physics, Boise State University, Boise, Idaho 83725-1570 (United States); Beltrán, J. J. [Department of Physics, Boise State University, Boise, Idaho 83725-1570 (United States); Grupo de Estado Sólido, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No 52-21, Medellín (Colombia); Barrero, C. A. [Grupo de Estado Sólido, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No 52-21, Medellín (Colombia)

    2014-05-07T23:59:59.000Z

    This work reports detailed investigations of a series of ?2.6?nm sized, Sn{sub 1?x}Fe{sub x}O{sub 2} crystallites with x?=?0–0.10 using Mossbauer spectroscopy, x-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance spectroscopy (EPR), and magnetometry to determine the oxidation state of Fe dopants and their role in the observed magnetic properties. The magnetic moment per Fe ion ? was the largest ?6.48?×?10{sup ?3} ?{sub B} for the sample with the lowest (0.001%) Fe doping, and it showed a rapid downward trend with increasing Fe doping. Majority of the Fe ions are in 3+ oxidation state occupying octahedral sites. Another significant fraction of Fe dopant ions is in 4+ oxidation state and a still smaller fraction might be existing as Fe{sup 2+} ions, both occupying distorted sites, presumably in the surface regions of the nanocrystals, near oxygen vacancies. These studies also suggest that the observed magnetism is not due to exchange coupling between Fe{sup 3+} spins. A more probable role for the multi-valent Fe ions may be to act as charge reservoirs, leading to charge transfer ferromagnetism.

  19. Magnetism and superconductivity in U?Pt<sub>xRh>(1–x)sub>C?

    SciTech Connect (OSTI)

    Wakeham, N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ni, Ni [Univ. of California, Los Angeles, CA (United States); Bauer, E. D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thompson, J. D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tegtmeier, E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ronning, F. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-01T23:59:59.000Z

    We report the phase diagram of the doping series U?Pt<sub>xRh>(1–x)sub>C?, studied through measurements of resistivity, specific heat, and magnetic susceptibility. The Néel temperature of U?Rh?C? of ~ 22 K is suppressed with increasing Pt content, reaching zero temperature close to x = 0.7, where we observed signatures of increased quantum fluctuations. In addition, evidence is presented that the antiferromagnetic state undergoes a spin-reorientation transition upon application of an applied magnetic field. This transition shows non-monotonic behavior as a function of x, peaking at around x = 0.3. Superconductivity is observed for x ? 0.9, with T<sub>c> increasing with increasing x. The reduction in T<sub>c> and increase in residual resistivity with decreasing Pt content is inconsistent with the extension of the Abrikosov-Gor'kov theory to unconventional superconductivity.

  20. Isotope Effect on Adsorbed Quantum Phases: Diffusion of H<sub>2sub> and D<sub>2sub> in Nanoporous Carbon

    SciTech Connect (OSTI)

    Contescu, Cristian I.; Zhang, Hongxin; Olsen, Raina J.; Mamontov, Eugene; Morris, James R.; Gallego, Nidia C.

    2013-06-01T23:59:59.000Z

    Quasielastic neutron scattering of H<sub>2sub> and D<sub>2sub> in the same nanoporous carbon at 10–40 K demonstrates extreme quantum sieving, with D<sub>2sub> diffusing up to 76 times faster. D<sub>2sub> also shows liquidlike diffusion while H<sub>2sub> exhibits Chudley-Elliott jump diffusion, evidence of their different relationships with the local lattice of adsorption sites due to quantum effects on intermolecular interactions. The onset of diffusion occurs at 22–25 K for H<sub>2sub> and 10–13 K for D<sub>2sub>. At these temperatures, H<sub>2sub> and D<sub>2sub> have identical thermal de Broglie wavelengths that correlate with the dominant pore size.

  1. Criticality Safety Study of UF<sub>6sub>and UO<sub>2sub>F>2sub>in 8-in. Inner Diameter Piping

    SciTech Connect (OSTI)

    Elam, K.R.

    2003-10-07T23:59:59.000Z

    The purpose of this report is to provide an evaluation of the criticality safety aspects of using up to 8-in.-inner-diameter (ID) piping as part of a system to monitor the {sup 235}U enrichment in uranium hexafluoride (UF{sub 6}) gas both before and after an enrichment down-blending operation. The evaluated operation does not include the blending stage but includes only the monitors and the piping directly associated with the monitors, which are in a separate room from the blending operation. There are active controls in place to limit the enrichment of the blended UF{sub 6} to a maximum of 5 weight percent (wt%) {sup 235}U. Under normal operating conditions of temperature and pressure, the UF{sub 6} will stay in the gas phase and criticality will not be credible. The two accidents of concern are solidification of the UF{sub 6} along with some hydrofluoric acid (HF) and water or moisture ingress, which would cause the UF{sub 6} gas to react and form a hydrated uranyl fluoride (UO{sub 2}F{sub 2}) solid or solution. Of these two types of accidents, the addition of water and formation of UO{sub 2}F{sub 2} is the most reactive scenario and thus limits related to UO{sub 2}F{sub 2} will bound the limits related to UF{sub 6}. Two types of systems are included in the monitoring process. The first measures the enrichment of the approximately 90 wt% enriched UF{sub 6} before it is blended. This system uses a maximum 4-in.-(10.16-cm-) ID pipe, which is smaller than the 13.7-cm-cylinder-diameter subcritical limit for UO{sub 2}F{sub 2} solution of any enrichment as given in Table 1 of American National Standard ANSI/ANS-8.1.1 Therefore, this system poses no criticality concerns for either accident scenario. The second type of system includes two enrichment monitors for lower-enriched UF{sub 6}. One monitors the approximately 1.5 wt% enriched UF{sub 6} entering the blending process, and the second monitors the approximately 5 wt% enriched UF{sub 6} coming out of the blending process. Both use a maximum 8-in.-(20.32-cm-) ID piping, where the length of the larger ID piping is approximately 9.5 m. This diameter of piping is below the 26.6-cm-cylinder-diameter subcritical limit for 5 wt% enriched UO{sub 2}F{sub 2} solutions as given in Table 6 of ANSI/ANS-8.1. Therefore, for up to 5 wt% enriched UF{sub 6}, this piping does not present a criticality concern for either accident scenario. Calculations were performed to determine the enrichment level at which criticality could become a concern in these 8-in.-ID piping sections. Both unreflected and fully water-reflected conditions were considered.

  2. Magnetic properties and magnetocaloric effects of Gd{sub x}Er{sub 1?x}Ga (0???x???1) compounds

    SciTech Connect (OSTI)

    Zheng, X. Q.; Wang, L. C.; Wu, R. R.; Hu, F. X.; Sun, J. R.; Shen, B. G., E-mail: shenbg@aphy.iphy.ac.cn [Institute of Physics, State key laboratory for Magnetism, Chinese Academy of Sciences, Beijing 100190 (China); Chen, J. [Beijing Institute of Aerospace Testing Technology, China Aerospace Science and Technology Corporation, Beijing 100074 (China)

    2014-05-07T23:59:59.000Z

    We carefully studied the magnetic properties and magnetocaloric effect of Gd{sub x}Er{sub 1-x}Ga (0???x???1) compounds. The Gd{sub x}Er{sub 1-x}Ga compounds undergo two magnetic transitions with temperature increasing: spin-reorientation or antiferromagnetic-to-ferromagnetic (FM) transition and FM-to-paramagnetic transition. As the content of Gd increases from 0 to 1, the transition temperature in low temperature region changes from 15?K to 66?K and the Curie temperature increases obviously from 30?K to 181.9?K. Although the maximum value of magnetic entropy change (?S{sub M}) for Gd{sub x}Er{sub 1?x}Ga decreases with the increase of x, the refrigerant capacity (RC) improves remarkably compared with that of ErGa compound. Table-like ?S{sub M} curves are observed for the compounds with x?=?0.1, 0.2, 0.3, and 0.4, which are very useful for real cooling applications. And Gd{sub 0.2}Er{sub 0.8}Ga and Gd{sub 0.3}Er{sub 0.7}Ga compounds show better magnetocaloric features than others in this series under considerations of both ?S{sub M} and RC. The results of this series of compounds show us a possible way to design and improve the magnetic refrigerant materials by making some substitutions.

  3. THE ORIGIN OF ASTEROID 162173 (1999 JU{sub 3})

    SciTech Connect (OSTI)

    Campins, Humberto [Physics Department, University of Central Florida, P.O. Box 162385, Orlando, FL 32816-2385 (United States); De Leon, Julia [Department of Edaphology and Geology, University of La Laguna, E-38071 Tenerife (Spain); Morbidelli, Alessandro; Gayon-Markt, Julie; Delbo, Marco; Michel, Patrick [Observatoire de la Cote d'Azur, Universite de Nice Sophia Antipolis (UNS), CNRS UMR7293, F-06108 Nice Cedex 2 (France); Licandro, Javier [Instituto de Astrofisica de Canarias (IAC), C/Via Lactea s/n, E-38205 La Laguna (Spain)

    2013-08-01T23:59:59.000Z

    Near-Earth asteroid (162173) 1999 JU{sub 3} (henceforth JU{sub 3}) is a potentially hazardous asteroid and the target of the Japanese Aerospace Exploration Agency's Hayabusa-2 sample return mission. JU{sub 3} is also a backup target for two other sample return missions: NASA's OSIRIS-REx and the European Space Agency's Marco Polo-R. We use dynamical information to identify an inner-belt, low-inclination origin through the {nu}{sub 6} resonance, more specifically, the region with 2.15 AU < a < 2.5 AU and i < 8 Degree-Sign . The geometric albedo of JU{sub 3} is 0.07 {+-} 0.01, and this inner-belt region contains four well-defined low-albedo asteroid families (Clarissa, Erigone, Polana, and Sulamitis), plus a recently identified background population of low-albedo asteroids outside these families. Only two of these five groups, the background and the Polana family, deliver JU{sub 3}-sized asteroids to the {nu}{sub 6} resonance, and the background delivers significantly more JU{sub 3}-sized asteroids. The available spectral evidence is also diagnostic; the visible and near-infrared spectra of JU{sub 3} indicate it is a C-type asteroid, which is compatible with members of the background, but not with the Polana family because it contains primarily B-type asteroids. Hence, this background population of low-albedo asteroids is the most likely source of JU{sub 3}.

  4. Strong Enhancement of Flux Pinning in YBa<sub>2sub>Cu>3sub>O>7-?sub> Multilayers with Columnar Defects Comprised of Self-Assembled BaZrO<sub>3sub>

    SciTech Connect (OSTI)

    Kang, Sukill [ORNL; Leonard, Keith J [ORNL; Martin, Patrick M [ORNL; Li, Jing [ORNL; Goyal, Amit [ORNL

    2007-01-01T23:59:59.000Z

    Multilayer structures comprising YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films with columns of self-assembled BaZrO{sub 3} (BZO) nanodots with interlayers of CeO{sub 2} or pure YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} were grown on rolling-assisted biaxially textured substrates (RABiTSs) using pulsed laser deposition. A significant enhancement of the critical current density (J{sub c}) was observed for the multilayers compared with a single layer of YBCO + BZO. J{sub c} varies as J{sub c}{approx}H{sup -{alpha}} with a of 0.27 for single layer of YBCO + BZO and 0.34 for both multilayered films. Enhancement of pinning in the multilayers is attributed to the presence of columnar defects comprised of self-assembled nanodots of BZO as well as planar CuO-type stacking defects arising as a result of interfacial reactions in the multilayers.

  5. Itinerant electrons, local moments, and magnetic correlations in the pnictide superconductors CeFeAsO??<sub>xFx>and Sr(Fe??<sub>xCox>)?As?

    SciTech Connect (OSTI)

    Vilmercati, Paolo; Fedorov, Alexei; Bondino, Federica; Offi, Francesco; Panaccione, Giancarlo; Lacovig, Paolo; Simonelli, Laura; McGuire, Michael A.; Sefat, Athena S. M.; Mandrus, David; Sales, Brian C.; Egami, Takeshi; Ku, Wei; Mannella, Norman

    2012-06-01T23:59:59.000Z

    A direct and element-specific measurement of the local Fe spin moment has been provided by analyzing the Fe 3s core level photoemission spectra in the parent and optimally doped CeFeAsO??<sub>xFx> (x = 0, 0.11) and Sr(Fe??<sub>xCox>)2As2 (x = 0, 0.10) pnictides. The rapid time scales of the photoemission process allowed the detection of large local spin moments fluctuating on a 10?¹? s time scale in the paramagnetic, antiferromagnetic, and superconducting phases, indicative of the occurrence of ubiquitous strong Hund's magnetic correlations. The magnitude of the spin moment is found to vary significantly among different families, 1.3?<sub>B> in CeFeAsO and 2.1?B in SrFe?As?. Surprisingly, the spin moment is found to decrease considerably in the optimally doped samples, 0.9?<sub>B> in CeFeAsO?.??F?.?? and 1.3?<sub>B> in Sr(Fe?.?Co?.?)?As?. The strong variation of the spin moment against doping and material type indicates that the spin moments and the motion of itinerant electrons are influenced reciprocally in a self-consistent fashion, reflecting the strong competition between the antiferromagnetic superexchange interaction among the spin moments and the kinetic energy gain of the itinerant electrons in the presence of a strong Hund's coupling. By describing the evolution of the magnetic correlations concomitant with the appearance of superconductivity, these results constitute a fundamental step toward attaining a correct description of the microscopic mechanisms shaping the electronic properties in the pnictides, including magnetism and high-temperature superconductivity.

  6. Rutgers Regional Report # Regional Report

    E-Print Network [OSTI]

    Garfunkel, Eric

    , population, income, and building permits over a 32-year period from 1969 to 2001 for the 31-county Tri counties of the Tri-State (Connecticut, New Jersey, and New York) Region have been divided for analytical the nation and the Tri-State Region. What has not been fully documented, however, is the apparent shift

  7. Influence of interface on structure and magnetic properties of Fe{sub 50}B{sub 50} nanoglass

    SciTech Connect (OSTI)

    Stoesser, A.; Kilmametov, A. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe (Germany); Ghafari, M., E-mail: mohammad.ghafari@kit.edu, E-mail: skamali@ucdavis.edu; Gleiter, H. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe (Germany); Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, Nanjing 210094 (China); Sakurai, Y.; Itou, M.; Kohara, S. [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Hahn, H. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe (Germany); Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, Nanjing 210094 (China); Joint Research Laboratory Nanomaterials, TU Darmstadt, Darmstadt (Germany); Kamali, S., E-mail: mohammad.ghafari@kit.edu, E-mail: skamali@ucdavis.edu [Department of Chemistry, University of California Davis, Davis, California 95616 (United States)

    2014-10-07T23:59:59.000Z

    In contrast to rapidly quenched metallic glasses, nanoglasses consist of two components, namely amorphous nanograins and interfacial regions with distinctively different properties. Various physical methods have been employed to obtain information on the atomistic and magnetic properties of such materials. For the case of a Fe{sub 50}B{sub 50} nanoglass, using high-energy X-ray diffraction, it was found that the short-range order of the nanograins is similar to that of a crystalline FeB alloy. Magnetic Compton scattering shows that the total magnetic moment is the sum of the magnetic moment of the nanograins and the weak magnetic moment of the interfacial regions (?{sub Interface}?=?+0.08??{sub B}). The measured moment of boron agrees (?{sub Boron}?=??0.08??{sub B}) with linear Muffin-Tin calculations. From the results of Mössbauer and magnetic Compton scattering, it can be concluded that the boron atoms segregate in the interfacial regions, resulting in a reduced boron concentration in the nanograins.

  8. ROTATIONAL EXCITATION AND RADIATIVE LIFETIMES OF N{sub 2}{sup +}

    SciTech Connect (OSTI)

    Mahan, Bruce H.; O'Keefe, Anthony

    1980-12-01T23:59:59.000Z

    The N{sub 2}{sup +} first negative system (B{sup 2}{Sigma}{sub u}{sup +} - X{sup 2}{Sigma}{sub g}{sup +}) has been recorded by laser induced fluorescences of N{sub 2}{sup +} ions confined in an rf trap. The ions were produced by electron impact and had an initial rotational distribution close to the room temperature distribution of the target N{sub 2} gas. By admitting Ar gas at pressures 10 to 100 times in excess of the N{sub 2} pressure, variable numbers of N{sub 2}{sup +} - Ar collisions were allowed to occur before the N{sub 2}{sup +} distribution was interrogated by the laser. Since the N{sub 2}{sup +} was translationally energetic, being driven by the trap fields, a rapid and extensive T to R energy transfer was observed. In this way, high rotational states of N{sub 2}{sup +} were populated and the radiative lifetimes of These states was measured. No evidence for a perturbation by a {sup 4}{Sigma}{sub u}{sup +} state was found in the region (N = 31, 32) where previous studies had indicated a possible perturbation. Evidence for enhanced charge transfer from N{sub 2}{sup +} X{sup 2} {Sigma}{sub g}{sup +} to Ar was found for N{sub 2}{sup +} in its first vibrational level.

  9. Centrosymmetric [N(CH{sub 3}){sub 4}]{sub 2}TiF{sub 6} vs. noncentrosymmetric polar [C(NH{sub 2}){sub 3}]{sub 2}TiF{sub 6}: A hydrogen-bonding effect on the out-of-center distortion of TiF{sub 6} octahedra

    SciTech Connect (OSTI)

    Kim, Eun-ah [Department of Chemistry Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of)] [Department of Chemistry Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Lee, Dong Woo [Department of Chemistry, Chung-Ang University, Seoul 156-756 (Korea, Republic of)] [Department of Chemistry, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Ok, Kang Min, E-mail: kmok@cau.ac.kr [Department of Chemistry, Chung-Ang University, Seoul 156-756 (Korea, Republic of)

    2012-11-15T23:59:59.000Z

    The syntheses, structures, and characterization of organically templated zero-dimensional titanium fluoride materials, A{sub 2}TiF{sub 6} (A=[N(CH{sub 3}){sub 4}] or [C(NH{sub 2}){sub 3}]), are reported. Phase pure samples of A{sub 2}TiF{sub 6} were synthesized by either solvothermal reaction method or a simple mixing method. While [N(CH{sub 3}){sub 4}]{sub 2}TiF{sub 6} crystallizes in a centrosymmetric space group, R-3, [C(NH{sub 2}){sub 3}]{sub 2}TiF{sub 6} crystallizes in a noncentrosymmetric polar space group, Cm. The asymmetric out-of-center distortion of TiF{sub 6} octahedra in polar [C(NH{sub 2}){sub 3}]{sub 2}TiF{sub 6} are attributable to the hydrogen-bonding interactions between the fluorine atoms in TiF{sub 6} octahedra and the nitrogen atoms in the [C(NH{sub 2}){sub 3}]{sup +} cation. Powder second-harmonic generation (SHG) measurements on the [C(NH{sub 2}){sub 3}]{sub 2}TiF{sub 6}, using 1064 nm radiation, indicate the material has SHG efficiency of 25 Multiplication-Sign that of {alpha}-SiO{sub 2}, which indicates an average nonlinear optical susceptibility, Left-Pointing-Angle-Bracket d{sub eff} Right-Pointing-Angle-Bracket {sub exp} of 2.8 pm/V. Additional SHG measurements reveal that the material is not phase-matchable (Type 1). The magnitudes of out-of-center distortions and dipole moment calculations for TiF{sub 6} octahedra will be also reported. - Graphical abstract: The out-of-center distortion of TiF{sub 6} octahedron in the polar noncentrosymmetric [C(NH{sub 2}){sub 3}]{sub 2}TiF{sub 6} is attributable to the hydrogen-bonding interactions between the F in TiF{sub 6} octahedron and the H-N in the [C(NH{sub 2}){sub 3}]{sup +}. Highlights: Black-Right-Pointing-Pointer Two titanium fluorides materials have been synthesized in high yields. Black-Right-Pointing-Pointer Hydrogen-bonds are crucial for the out-of-center distortion of TiF{sub 6} octahedra. Black-Right-Pointing-Pointer [C(NH{sub 2}){sub 3}]{sub 2}TiF{sub 6} has a SHG efficiency of 25 Multiplication-Sign that of {alpha}-SiO{sub 2}.

  10. A Rh<sub>xSy>/C Catalyst for the Hydrogen Oxidation and Hydrogen Evolution Reactions in HBr

    SciTech Connect (OSTI)

    Masud, Jahangir [Univ. of Kansas, Lawrence, KS (United States); Nguyena, Trung V. [Univ. of Kansas, Lawrence, KS (United States); Singh, Nirala [Univ. of California, Santa Barbara, CA (United States); McFarland, Eric [Univ. of California, Santa Barbara, CA (United States); Ikenberry, Myles [Kansas State Univ., Manhattan, KS (United States); Hohn, Keith [Kansas State Univ., Manhattan, KS (United States); Pan, Chun-Jern [National Taiwan University of Science & Technology, Tapei (Taiwan); Hwang, Bing-Joe [National Taiwan University of Science & Technology, Tapei (Taiwan)

    2015-01-01T23:59:59.000Z

    Rhodium sulfide (Rh<sub>2sub>S>3sub>) on carbon support was synthesized by refluxing rhodium chloride with ammonium thiosulfate. Thermal treatment of Rh<sub>2sub>S>3sub> at high temperatures (600°C to 850°C) in presence of argon resulted in the transformation of Rh<sub>2sub>S>3sub> into Rh<sub>3sub>S>4sub>, Rh<sub>17sub>S>15sub> and Rh which were characterized by TGA/DTA, XRD, EDX, and deconvolved XPS analyses. The catalyst particle size distribution ranged from 3 to 12 nm. Cyclic voltammetry and rotating disk electrode measurements were used to evaluate the catalytic activity for hydrogen oxidation and evolution reactions in H<sub>2sub>SO>4sub> and HBr solutions. The thermally treated catalysts show high activity for the hydrogen reactions. The exchange current densities (i<sub>o>) of the synthesized Rh<sub>xSy> catalysts in H<sub>2sub>-saturated 1M H<sub>2sub>SO>4sub> and 1M HBr for HER and HOR were 0.9 mA/cm2 to 1.0 mA/cm2 and 0.8 to 0.9 mA/cm2, respectively. The lower i<sub>o> values obtained in 1M HBr solution compared to in H<sub>2sub>SO>4sub> might be due to the adsorption of Br- on the active surface. Stable electrochemical active surface area (ECSA) of Rh<sub>xSy> catalyst was obtained for CV scan limits between 0 V and 0.65 V vs. RHE. Scans with upper voltage limit beyond 0.65 V led to decreased and unreproducible ECSA measurements.

  11. Conversion of closo-2,4-C/sub 2/B/sub 5/H/sub 7/ to (nido-2,4-C/sub 2/B/sub 4/H/sub 7/)/sup /minus//

    SciTech Connect (OSTI)

    Abdou, Z.J.; Gomez, F.; Abdou, G.; Onak, T.

    1988-10-05T23:59:59.000Z

    A method for the conversion of closo-2-,4-C/sub 2/B/sub 5/H/sub 7/ to (nido-2,4-CB/sub 4/H/sub 7/)/sup /minus// by the use of Li(N(R)/sub 2/), R = CH/sub 3/, C/sub 2/H/sub 5/, CH(CH/sub 3/)/sub 2/, as the reagent and acetonitrile as the solvent. The stoichiometry for the reaction appears to be somewhat greater than 1:1 Li(N(R)/sub 2/):C/sub 2/B/sub 5/H/sub 7/. The reaction was found to be nearly quantitative at room temperature. The /sup 11/B NMR spectrum shows that there are at least two intermediates in the reaction. 14 references, 2 figures.

  12. Metal alkoxides. Models for metal oxides. 15. Carbon-carbon and carbon-hydrogen bond activation in the reactions between ethylene and ditungsten hexaalkoxides: W sub 2 (OCH sub 2 -t-Bu) sub 6 (. eta. sup 2 -C sub 2 H sub 4 ) sub 2 , W sub 2 (OR) sub 6 (CH sub 2 ) sub 4 (. eta. sup 2 -C sub 2 H sub 4 ), and W sub 2 (OR) sub 6 (. mu. -CCH sub 2 CH sub 2 CH sub 2 ) (where r = CH sub 2 -t-Bu, i-Pr, c-C sub 5 h sub 9 , and c-C sub 6 H sub 11 ). Preparations, properties, structures, and reaction mechanisms

    SciTech Connect (OSTI)

    Chisholm, M.H.; Huffman, J.C.; Hampden-Smith, M.J. (Indiana Univ., Bloomington (USA))

    1989-07-05T23:59:59.000Z

    W{sub 2}(OR){sub 6} (M {triple bond}M) compounds and ethylene (1 atm, 22{degree}C) react in alkane and aromatic hydrocarbon solvents to give W{sub 2}(OR){sub 6}({mu}-CCH{sub 2}CH{sub 2}CH{sub 2}) compounds and ethane, where R = i-Pr, c-C{sub 5}H{sub 9}, c-C{sub 6}H{sub 11}, and CH{sub 2}-t-Bu. Under comparable conditions, W{sub 2}(O-t-Bu){sub 6} and ethylene fail to react. In the formation of W{sub 2}(OR){sub 6}({mu}-CCH{sub 2}CH{sub 2}CH{sub 2}) compounds, the intermediates W{sub 2}(OCH{sub 2}-t-Bu){sub 6}({eta}{sup 2}-C{sub 2}H{sub 4}){sub 2} and W{sub 2}(OR){sub 6}(CH{sub 2}){sub 4}({eta}{sup 2}-C{sub 2}H{sub 4}), where R = C-C{sub 5}H{sub 9}, i-Pr, and CH{sub 2}-t-Bu, have been characterized. For R = i-Pr and CH{sub 2}-t-Bu, the intermediates are shown to be formed reversibly from W{sub 2}(OR){sub 6} and ethylene. The compound W{sub 2}(O-i-Pr){sub 6}(CH{sub 2}){sub 4}({eta}{sup 2}-C{sub 2}H{sub 4}) has been fully characterized by an X-ray study and found to contain a metallacyclopentane ring and a W-{eta}{sup 2}-C{sub 2}H{sub 4} moiety, one at each metal center. The pyridine adduct W{sub 2}(O-i-Pr){sub 6}({mu}-CCH{sub 2}CH{sub 2}ch{sub 2})(py) has been fully characterized and shown to contain a novel 1,6-dimetallabicyclo(3.1.0)hex-1(5)-ene organometallic core. All compounds have been characterized by {sup 13}C and {sup 1}H NMR studies. Various aspects of the reaction pathway have been probed by the use of isotopically labeled ethylenes, and a proposed general scheme is compared to previous studies of ethylene activation at mononuclear metal centers and carbonyl dinuclear and cluster compounds.

  13. Syntheses, structures, and properties of Ag{sub 4}(Mo{sub 2}O{sub 5})(SeO{sub 4}){sub 2}(SeO{sub 3}) and Ag{sub 2}(MoO{sub 3}){sub 3}SeO{sub 3}

    SciTech Connect (OSTI)

    Ling Jie [Department of Chemistry and Biochemistry, 179 Chemistry Building, Auburn University, Auburn, AL 36849 (United States); Albrecht-Schmitt, Thomas E. [Department of Chemistry and Biochemistry, 179 Chemistry Building, Auburn University, Auburn, AL 36849 (United States)], E-mail: albreth@auburn.edu

    2007-05-15T23:59:59.000Z

    Ag{sub 4}(Mo{sub 2}O{sub 5})(SeO{sub 4}){sub 2}(SeO{sub 3}) has been synthesized by reacting AgNO{sub 3}, MoO{sub 3}, and selenic acid under mild hydrothermal conditions. The structure of this compound consists of cis-MoO{sub 2} {sup 2+} molybdenyl units that are bridged to neighboring molybdenyl moieties by selenate anions and by a bridging oxo anion. These dimeric units are joined by selenite anions to yield zigzag one-dimensional chains that extended down the c-axis. Individual chains are polar with the C {sub 2} distortion of the Mo(VI) octahedra aligning on one side of each chain. However, the overall structure is centrosymmetric because neighboring chains have opposite alignment of the C {sub 2} distortion. Upon heating Ag{sub 4}(Mo{sub 2}O{sub 5})(SeO{sub 4}){sub 2}(SeO{sub 3}) looses SeO{sub 2} in two distinct steps to yield Ag{sub 2}MoO{sub 4}. Crystallographic data: (193 K; MoK{alpha}, {lambda}=0.71073 A): orthorhombic, space group Pbcm, a=5.6557(3), b=15.8904(7), c=15.7938(7) A, V=1419.41(12), Z=4, R(F)=2.72% for 121 parameters with 1829 reflections with I>2{sigma}(I). Ag{sub 2}(MoO{sub 3}){sub 3}SeO{sub 3} was synthesized by reacting AgNO{sub 3} with MoO{sub 3}, SeO{sub 2}, and HF under hydrothermal conditions. The structure of Ag{sub 2}(MoO{sub 3}){sub 3}SeO{sub 3} consists of three crystallographically unique Mo(VI) centers that are in 2+2+2 coordination environments with two long, two intermediate, and two short bonds. These MoO{sub 6} units are connected to form a molybdenyl ribbon that extends along the c-axis. These ribbons are further connected together through tridentate selenite anions to form two-dimensional layers in the [bc] plane. Crystallographic data: (193 K; MoK{alpha}, {lambda}=0.71073 A): monoclinic, space group P2{sub 1} /n, a=7.7034(5), b=11.1485(8), c=12.7500(9) A, {beta}=105.018(1) V=1002.7(2), Z=4, R(F)=3.45% for 164 parameters with 2454 reflections with I>2{sigma}(I). Ag{sub 2}(MoO{sub 3}){sub 3}SeO{sub 3} decomposes to Ag{sub 2}Mo{sub 3}O{sub 10} on heating above 550 deg. C. - Graphical abstract: A view of the one-dimensional [(Mo{sub 2}O{sub 5})(SeO{sub 4}){sub 2}(SeO{sub 3})]{sup 4-} chains that extend down the c-axis in the structure of Ag{sub 4}(Mo{sub 2}O{sub 5})(SeO{sub 4}){sub 2}(SeO{sub 3})

  14. Effect of nanosized Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} on the transport critical current density of Bi{sub 1.6}Pb{sub 0.4}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} superconductor

    SciTech Connect (OSTI)

    Hafiz, M.; Abd-Shukor, R. [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2014-09-03T23:59:59.000Z

    The effects of nano-sized Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} addition on the superconducting and transport properties of Bi{sub 1.6}Pb{sub 0.4}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} (Bi-2223) in bulk form has been investigated. Bi-2223 superconductor was fabricated using co-precipitation method and 0.01 – 0.05 wt% of Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} nanoparticles with average size of 20 nm were added into the samples. The critical temperature (T{sub c}) and critical current density (J{sub c}) of the samples were measured by using the four-point probe method, while the phase formation and microstructure of the samples were examined using x-ray diffraction and SEM respectively. It was found that J{sub c} of all samples added with Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} were higher than non-added sample, with x = 0.01 wt. % sample showing the highest J{sub c}. This study showed that small addition of nano-Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} can effectively enhance the transport critical current density in Bi-2223 superconductor.

  15. Substrate step-edge YBa sub 2 Cu sub 3 O sub 7 rf SQUIDs

    SciTech Connect (OSTI)

    Daly, K.P.; Dozier, W.D.; Burch, J.F.; Coons, S.B.; Hu, R.; Platt, C.E.; Simon, R.W. (TRW Space Technology Group, One Space Park, Redondo Beach, California 90278 (US))

    1991-02-04T23:59:59.000Z

    We have developed a technique which permits high-yield fabrication of microbridges and low noise YBa{sub 2}Cu{sub 3}O{sub 7} superconducting quantum interference devices (SQUIDs) in epitaxial thin films. These SQUIDs operate over a wide temperature range extending from 4 K to close to the superconducting transition temperature. Measurements of an rf SQUID operating at 77 K give a peak-to-peak flux sensitivity of 36 {mu}V/{Phi}{sub 0} and a flux noise at 10 Hz of 1.5{times} 10{sup {minus}4} {Phi}{sub 0}/{radical}Hz. Device yields over 80% have been obtained.

  16. Syntheses, crystal structures and optical properties of the first strontium selenium(IV) and tellurium(IV) oxychlorides: Sr{sub 3}(SeO{sub 3})(Se{sub 2}O{sub 5})Cl{sub 2} and Sr{sub 4}(Te{sub 3}O{sub 8})Cl{sub 4}

    SciTech Connect (OSTI)

    Jiang Hailong [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Mao Jianggao [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China)], E-mail: mjg@fjirsm.ac.cn

    2008-02-15T23:59:59.000Z

    Two new quaternary strontium selenium(IV) and tellurium(IV) oxychlorides, namely, Sr{sub 3}(SeO{sub 3})(Se{sub 2}O{sub 5})Cl{sub 2} and Sr{sub 4}(Te{sub 3}O{sub 8})Cl{sub 4}, have been prepared by solid-state reaction. Sr{sub 3}(SeO{sub 3})(Se{sub 2}O{sub 5})Cl{sub 2} features a three-dimensional (3D) network structure constructed from strontium(II) interconnected by Cl{sup -}, SeO{sub 3}{sup 2-} as well as Se{sub 2}O{sub 5}{sup 2-} anions. The structure of Sr{sub 4}(Te{sub 3}O{sub 8})Cl{sub 4} features a 3D network in which the strontium tellurium oxide slabs are interconnected by bridging Cl{sup -} anions. The diffuse reflectance spectrum measurements and results of the electronic band structure calculations indicate that both compounds are wide band-gap semiconductors. - Graphical abstract: Solid-state reactions of SrO, SrCl{sub 2}, and SeO{sub 2} or TeO{sub 2} in different molar ratios and under different temperatures lead to two new strontium selenium(IV) or tellurium(IV) oxychlorides with two different types of structures, namely, Sr{sub 3}(SeO{sub 3})(Se{sub 2}O{sub 5})Cl{sub 2} and Sr{sub 4}(Te{sub 3}O{sub 8})Cl{sub 4}. Both compounds are wide band-gap semiconductors based on the diffuse reflectance spectra and the electronic band structures.

  17. Preparation, characterization and luminescence of La{sub 2}TeO{sub 6} phosphor doped with Eu{sup 3+}

    SciTech Connect (OSTI)

    Llanos, Jaime [Departamento de Quimica, Universidad Catolica del Norte, Avda. Angamos 0610, Casilla 1280, Antofagasta (Chile)], E-mail: jllanos@ucn.cl; Cortes, Rodrigo [Departamento de Quimica, Universidad Catolica del Norte, Avda. Angamos 0610, Casilla 1280, Antofagasta (Chile)

    2008-10-02T23:59:59.000Z

    Phosphors of La{sub 2}TeO{sub 6} doped with Eu{sup 3+} ions have been synthesized by the oxidation of the corresponding rare-earths oxytellurides of formula La{sub 2-x}Eu{sub x}O{sub 2}Te (x = 0.02, 0.06, and 0.1) at 1050 K. Powder X-ray diffraction confirms that the as prepared materials consist of the orthorhombic La{sub 2}TeO{sub 6} as main phase. The photoluminescence (PL) of red-emitting La{sub 2-x}Eu{sub x}TeO{sub 6} powder phosphors is reported. The emission spectrum, exhibits an intense emission peak due to {sup 5}D{sub 0} {yields} {sup 7}F{sub 2} transition at 616 nm, which indicates that the Eu{sup 3+} ion occupies a non-centrosymmetric site in the host lattice. These materials could find application for use as lamp phosphors in the red region.

  18. SOUTHWEST REGIONAL PARTNERSHIP FOR CARBON SEQUESTRATION

    SciTech Connect (OSTI)

    Brian McPherson

    2004-04-01T23:59:59.000Z

    The Southwest Partnership Region includes five states (Arizona, Colorado, New Mexico, Oklahoma, Utah) and contiguous areas from three adjacent states (west Texas, south Wyoming, and west Kansas). This energy-rich region exhibits some of the largest growth rates in the nation, and it contains two major CO{sub 2} pipeline networks that presently tap natural subsurface CO{sub 2} reservoirs for enhanced oil recovery at a rate of 30 million tons per year. The ten largest coal-fired power plants in the region produce 50% (140 million tons CO{sub 2}/y) of the total CO{sub 2} from power-plant fossil fuel combustion, with power plant emissions close to half the total CO{sub 2} emissions. The Southwest Regional Partnership comprises a large, diverse group of expert organizations and individuals specializing in carbon sequestration science and engineering, as well as public policy and outreach. These partners include 21 state government agencies and universities, the five major electric utility industries, seven oil, gas and coal companies, three federal agencies, the Navajo Nation, several NGOs including the Western Governors Association, and data sharing agreements with four other surrounding states. The Partnership is developing action plans for possible Phase II carbon sequestration pilot tests in the region, as well as the non-technical aspects necessary for developing and carrying out these pilot tests. The establishment of a website network to facilitate data storage and information sharing, decision-making, and future management of carbon sequestration in the region is a priority. The Southwest Partnership's approach includes (1) dissemination of existing regulatory/permitting requirements, (2) assessing and initiating public acceptance of possible sequestration approaches, and (3) evaluation and ranking of the most appropriate sequestration technologies for capture and storage of CO{sub 2} in the Southwest Region. The Partnership will also identify potential gaps in monitoring and verification approaches needed to validate long-term storage efforts.

  19. Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2}: A new bismuth oxo-selenite bromide

    SciTech Connect (OSTI)

    Berdonosov, Peter S., E-mail: berdonosov@inorg.chem.msu.ru [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Olenev, Andrei V. [SineTheta Ltd., MSU Building 1-77, 119991 Moscow (Russian Federation)] [SineTheta Ltd., MSU Building 1-77, 119991 Moscow (Russian Federation); Kirsanova, Maria A. [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)] [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Lebed, Julia B. [Institute for nuclear research RAS, 142190, Troitsk, Moscow region (Russian Federation)] [Institute for nuclear research RAS, 142190, Troitsk, Moscow region (Russian Federation); Dolgikh, Valery A. [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)] [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)

    2012-12-15T23:59:59.000Z

    A new bismuth oxo-selenite bromide Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2} was synthesized and structurally characterized. The crystal structure belongs to the triclinic system (space group P1-bar , Z=2, a=7.1253(7) A, b=10.972(1) A, c=12.117(1) A, {alpha}=67.765(7) Degree-Sign , {beta}=82.188(8) Degree-Sign , {gamma}=78.445(7) Degree-Sign ) and is unrelated to those of other known oxo-selenite halides. It can be considered as an open framework composed of BiO{sub x} or BiO{sub y}Br{sub z} polyhedrons forming channels running along [1 0 0] direction which contain the selenium atoms in pyramidal shape oxygen coordination (SeO{sub 3}E). The spectroscopic properties and thermal stability were studied. The new compound is stable up to 400 Degree-Sign C. - graphical abstract: New bismuth oxo-selenite bromide with new open framework structure. Highlights: Black-Right-Pointing-Pointer New bismuth oxo-selenite bromide was found and structurally characterized. Black-Right-Pointing-Pointer Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2} exhibit a new open framework structure type. Black-Right-Pointing-Pointer BiO{sub x} or BiO{sub y}Br{sub z} polyhedrons form channels in the structure which are decorated by [SeO{sub 3}E] groups.

  20. Syntheses, crystal structures and characterizations of BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2}

    SciTech Connect (OSTI)

    Jiang Hailong [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China); Feng Meiling [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China); Mao Jianggao [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China)]. E-mail: mjg@ms.fjirsm.ac.cn

    2006-06-15T23:59:59.000Z

    Two new barium zinc selenite and tellurite, namely, BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2}, have been synthesized by the solid state reaction. The structure of BaZn(SeO{sub 3}){sub 2} features double chains of [Zn(SeO{sub 3}){sub 2}]{sup 2-} anions composed of four- and eight-member rings which are alternatively along a-axis. The double chains of [Zn{sub 2}(TeO{sub 3}){sub 2}Cl{sub 3}]{sup 3-} anions in BaZn(TeO{sub 3})Cl{sub 2} are formed by Zn{sub 3}Te{sub 3} rings in which each tellurite group connects with three ZnO{sub 3}Cl tetrahedra. BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2} are wide bandgap semiconductors based on optical diffuse reflectance spectrum measurements. -- Graphical abstract: Two new barium zinc selenite and tellurite, namely, BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2}, have been synthesized by solid state reaction. The structure of BaZn(SeO{sub 3}){sub 2} features 1D double chains of [Zn(SeO{sub 3}){sub 2}]{sup 2-} anions composed of four- and eight-member rings which are alternatively along a-axis. The 1D double chains of [Zn{sub 2}(TeO{sub 3}){sub 2}Cl{sub 3}]{sup 3-} anions in BaZn(TeO{sub 3})Cl{sub 2} are formed by Zn{sub 3}Te{sub 3} rings in which each tellurite group connects with one ZnO{sub 3}Cl and two ZnO{sub 2}Cl{sub 2} tetrahedra. BaZn(SeO{sub 3}){sub 2} and BaZn(TeO{sub 3})Cl{sub 2} are wide bandgap semiconductors based on optical diffuse reflectance spectrum measurements.

  1. Blackout Final Implementation Report

    Office of Environmental Management (EM)

    Task Force: Final Report on Implementation of Recommendations G R23. Strengthen reactive power and voltage control practices in all NERC regions. . . . . . . . . . . . . . 34 R24....

  2. Supplemental Tables to the Annual Energy Outlook - Energy Information...

    Gasoline and Diesel Fuel Update (EIA)

    and Assumptions Acronyms NEMS: An Overview Assumptions report (2011) NERC Region map Levelized generation costs Capital cost for electricity plants About the National Energy...

  3. Structural chemistry and magnetic properties of Nd{sub 18}Li{sub 8}Fe{sub 4}M?O{sub 39} (M?=Al, Ga) and La{sub 18}Li{sub 8}Fe{sub 4.5}In{sub 0.5}O{sub 39}

    SciTech Connect (OSTI)

    Thammajak, Nirawat; Battle, Peter D., E-mail: peter.battle@chem.ox.ac.uk; Brown, Catherine; Higgon, Katherine; Stansfield, Rhian

    2014-01-15T23:59:59.000Z

    Polycrystalline samples of Nd{sub 18}Li{sub 8}Fe{sub 4}M?O{sub 39} (M?=Al, Ga) and La{sub 18}Li{sub 8}Fe{sub 4.5}In{sub 0.5}O{sub 39} have been prepared by the ceramic method and characterised by neutron diffraction and magnetometry. All three compounds adopt a cubic structure (space group Pm3{sup ¯}n, a ?12 Å) based on intersecting ?1 1 1? chains of cation sites with alternating octahedral and prismatic coordination geometry. These sites are occupied by Li, Fe and M? or In; Nd or La cations occupy sites between the chains. The cation distribution over the octahedral and prismatic sites within the chains is disordered in all three compounds. The Nd-containing compositions show spin-glass behaviour below ?4.5 K whereas small, weakly-ferrimagnetic domains form in La{sub 18}Li{sub 8}Fe{sub 4.5}In{sub 0.5}O{sub 39} below 7.60 K. The dependence of the magnetic properties on the nature of the lanthanide cation is discussed. - Graphical abstract: At low temperatures Nd{sub 18}Li{sub 8}Fe{sub 4}M?O{sub 39} (M’=Al, Ga) behave as spin glasses whereas small ferrimagnetic domains form in La{sub 18}Li{sub 8}Fe{sub 4.5}In{sub 0.5}O{sub 39}. Display Omitted - Highlights: • p-Block cations can be accommodated in the La{sub 18}Li{sub 8}Rh{sub 5}O{sub 39} structure. • Small ferrimagnetic domains in La{sub 18}Li{sub 8}Fe{sub 4.5}In{sub 0.5}O{sub 39}. • Magnetic behaviour controlled by the lanthanide cation.

  4. Nanocrystallization in spark plasma sintered Fe{sub 48}Cr{sub 15}Mo{sub 14}Y{sub 2}C{sub 15}B{sub 6} bulk amorphous alloy

    SciTech Connect (OSTI)

    Singh, Ashish; Harimkar, Sandip P. [School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)] [School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, Oklahoma 74078 (United States); Katakam, Shravana; Dahotre, Narendra B. [Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76203 (United States)] [Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76203 (United States); Ilavsky, Jan [Advanced Photon Source, Argonne National Laboratory, Chicago, Illinois 60439 (United States)] [Advanced Photon Source, Argonne National Laboratory, Chicago, Illinois 60439 (United States)

    2013-08-07T23:59:59.000Z

    Spark plasma sintering (SPS) is evolving as an attractive process for the processing of multi-component Fe-based bulk amorphous alloys and their in-situ nanocomposites with controlled primary nanocrystallization. Extended Q-range small angle neutron scattering (EQ-SANS) analysis, complemented by x-ray diffraction and transmission electron microscopy, was performed to characterize nanocrystallization behavior of SPS sintered Fe-based bulk amorphous alloys. The SANS experiments show significant scattering for the samples sintered in the supercooled region indicating local structural/compositional changes associated with the profuse nucleation of nanoclusters (?4 nm). For the samples spark plasma sintered near and above crystallization temperature (>653 °C), the SANS data show the formation of interference maximum indicating the formation and growth of (Fe,Cr){sub 23}C{sub 6} crystallites. The SANS data also indicate the evolution of bimodal crystallite distribution at higher sintering temperatures (above T{sub x1}). The growth of primary nanocrystallites results in impingement of concentration gradient fields (soft impingement effect), leading to non-random nucleation of crystallites near the primary crystallization.

  5. Investigation of reactive ion etching of dielectrics and Si in CHF{sub 3}/O{sub 2} or CHF{sub 3}/Ar for photovoltaic applications

    SciTech Connect (OSTI)

    Gatzert, C.; Blakers, A. W.; Deenapanray, Prakash N. K.; Macdonald, D.; Auret, F. D. [Centre for Sustainable Energy Systems, Faculty of Engineering and Information Technology, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Department of Engineering, Faculty of Engineering and Information Technology, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Department of Physics, University of Pretoria, Pretoria 0002 (South Africa)

    2006-09-15T23:59:59.000Z

    Using a combination of etch rate, photoconductance, and deep level transient spectroscopy (DLTS) measurements, the authors have investigated the use of reactive ion etching (RIE) of dielectrics and Si in CHF{sub 3}/O{sub 2} and CHF{sub 3}/Ar plasmas for photovoltaic applications. The radio frequency power (rf-power) and gas flow rate dependencies have shown that the addition of either O{sub 2} or Ar to CHF{sub 3} can be used effectively to change the etch selectivity between SiO{sub 2} and Si{sub 3}N{sub 4}. The effective carrier lifetime of samples degraded upon exposure to a CHF{sub 3}-based plasma, reflecting the introduction of recombination centers in the near-surface region. The extent of minority carrier lifetime degradation was similar in both types of plasmas, suggesting that the same defects were responsible for the increased recombination. However, the rf-power dependence of lifetime degradation in n- and p-type Si was different. Moreover, the lifetime degradation did not exhibit a linear rf-power dependence, suggesting that primary defects were not the dominant recombination centers responsible for the decrease in lifetime. Indeed, DLTS measurements have shown that secondary defects were formed in samples exposed to the plasma after annealing at 400 deg. C, the temperature at which a SiN:H layer is deposited on samples to passivate their surfaces. The minority carrier lifetime degradation in RIE processed samples could be partially avoided using post-RIE chemical treatments.

  6. Controlling superconductivity in La<sub>2-xsub>SrxCuO>4+?sub> by ozone and vacuum annealing

    SciTech Connect (OSTI)

    Leng, Xiang [Brookhaven National Lab. (BNL), Upton, NY (United States); Bozovic, Ivan [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-01-01T23:59:59.000Z

    In this study we performed a series of ozone and vacuum annealing experiments on epitaxial La<sub>2-xsub>SrxCuO>4+?sub> thin films. The transition temperature after each annealing step has been measured by the mutual inductance technique. The relationship between the effective doping and the vacuum annealing time has been studied. Short-time ozone annealing at 470 °C oxidizes an underdoped film all the way to the overdoped regime. The subsequent vacuum annealing at 350 °C to 380 °C slowly brings the sample across the optimal doping point back to the undoped, non-superconducting state. Several ozone and vacuum annealing cycles have been done on the same sample and the effects were found to be repeatable and reversible Vacuum annealing of ozone-loaded LSCO films is a very controllable process, allowing one to tune the doping level of LSCO in small steps across the superconducting dome, which can be used for fundamental physics studies.

  7. Structure and optical properties of a noncentrosymmetric borate RbSr{sub 4}(BO{sub 3}){sub 3}

    SciTech Connect (OSTI)

    Xia, M.J. [Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Li, R.K., E-mail: rkli@mail.ipc.ac.cn [Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2013-01-15T23:59:59.000Z

    A new noncentrosymmetric borate, RbSr{sub 4}(BO{sub 3}){sub 3} (abbreviated as RSBO), has been grown from Rb{sub 2}O--B{sub 2}O{sub 3}--RbF flux and its crystal structure was determined by single crystal x-ray diffraction. It crystallizes in space group Ama2 with cell parameters of a=11.128(10) A, b=12.155(15) A, c=6.952(7) A, Z=4. The basic structural units are isolated planar BO{sub 3} groups. Second harmonic generation (SHG) test of the title compound by the Kurtz-Perry method shows that RSBO can be phase matchable with an effective SHG coefficient about two-thirds as large as that of KH{sub 2}PO{sub 4} (KDP). Finally, based on the anionic group approximation, the optical properties of the title compound are compared with those of the structure-related apatite-like compounds with the formula 'A{sub 5}(TO{sub n}){sub 3}X'. - Graphical abstract: RbSr{sub 4}(BO{sub 3}){sub 3} and some other borate NLO compounds, namely Ca{sub 5}(BO{sub 3}){sub 3}F RCa{sub 4}(BO{sub 3}){sub 3}O (R=Y or Gd) and Na{sub 3}La{sub 2}(BO{sub 3}){sub 3} can be viewed as the derivatives of apatite. They have similar formula composed of five cations and three anion groups (we call them 5/3 structures). The detailed SHG coefficients and optical properties of the apatite-like NLO crystals were compared and summarized. Highlights: Black-Right-Pointing-Pointer A new noncentrosymmetric borate RbSr{sub 4}(BO{sub 3}){sub 3} was grown from flux. Black-Right-Pointing-Pointer The RbSr{sub 4}(BO{sub 3}){sub 3} can be viewed as a derivative of the apatite-like structure. Black-Right-Pointing-Pointer The structure and its relationship to the optical properties of RbSr{sub 4}(BO{sub 3}){sub 3} are compared with other NLO crystals with apatite-like structures. Black-Right-Pointing-Pointer The basic structural units are the planar BO{sub 3} groups in the structure. Black-Right-Pointing-Pointer Second harmonic generation (SHG) test shows that RbSr{sub 4}(BO{sub 3}){sub 3} can be phase matchable with an effective SHG coefficient about two-thirds as large as that of KH{sub 2}PO{sub 4}.

  8. Sub-micron filter

    DOE Patents [OSTI]

    Tepper, Frederick (Sanford, FL); Kaledin, Leonid (Port Orange, FL)

    2009-10-13T23:59:59.000Z

    Aluminum hydroxide fibers approximately 2 nanometers in diameter and with surface areas ranging from 200 to 650 m.sup.2/g have been found to be highly electropositive. When dispersed in water they are able to attach to and retain electronegative particles. When combined into a composite filter with other fibers or particles they can filter bacteria and nano size particulates such as viruses and colloidal particles at high flux through the filter. Such filters can be used for purification and sterilization of water, biological, medical and pharmaceutical fluids, and as a collector/concentrator for detection and assay of microbes and viruses. The alumina fibers are also capable of filtering sub-micron inorganic and metallic particles to produce ultra pure water. The fibers are suitable as a substrate for growth of cells. Macromolecules such as proteins may be separated from each other based on their electronegative charges.

  9. Vibrational analysis of the elpasolites Cs{sub 2}NaAlF{sub 6} and Cs{sub 2}NaGaF{sub 6} doped with Cr{sup 3+} ions by fluorescence spectroscopy.

    SciTech Connect (OSTI)

    Bordallo, H. N.; Sosman, L. P.; Tavares, A. D., Jr.; da Fonseca, R. J. M.

    1999-09-07T23:59:59.000Z

    Interest in 3d transition metal impurities in ionic crystals has increased due to their important role in the laser activity of these materials. Moreover, recent advances in tunable solid-state lasers and high-power semiconductor laser diode arrays have generated a strong interest in investigating new compounds that emit in the visible and near-infrared spectral regions. In particular, many optical studies have been devoted to Cr{sup 3+}-doped fluoride crystals as a consequence of the high quality of some Cr{sup 3+}-based laser materials. In the present investigation, the low temperature emission spectra of Cr{sup 3+} ions in the hexagonal elpasolites Cs{sub 2}NaAlF{sub 6} and Cs{sub 2}NaGaF{sub 6} have been measured. Each compound has two crystallographically inequivalent octahedral sites for the Al{sup 3+} and Ga{sup 3+} ions that can be occupied by Cr{sup 3+} ions. For both materials, the luminescence spectrum presents two zero-phonon lines accompanied by a well-defined vibrational structure. The different peaks of the emission broadband are described in terms of phonons of the lattice and normal modes of the octahedral complex [CrF{sub 6}]{sup 3{minus}}. A detailed analysis of the vibrational structure observed leads to the conclusion that the {sup 2}E and {sup 4}T{sub 2} excited states of the [CrF{sub 6}]{sup 3{minus}} ions are displaced along the e{sub g}, a{sub 1g} and probably the t{sub 2g} coordinates.

  10. Thermoelectric properties of p-type (Bi{sub 1{minus}x}Sb{sub x}){sub 2}Te{sub 3} fabricated by mechanical alloying process

    SciTech Connect (OSTI)

    Jung, B.Y.; Choi, J.S.; Oh, T.S.; Hyun, D.B.

    1997-07-01T23:59:59.000Z

    Thermoelectric properties of polycrystalline (Bi{sub 1{minus}x}Sb{sub x}){sub 2}Te{sub 3} (0.75 {le} x {le} 0.85), fabricated by mechanical alloying and hot pressing methods, have been investigated. Formation of (Bi{sub 0.25}Sb{sub 0.75}){sub 2}Te{sub 3} alloy powder was completed by mechanical alloying for 5 hours at ball-to-material ratio of 5:1, and processing time for (Bi{sub 1{minus}sub x}Sb{sub x}){sub 2}Te{sub 3} formation increased with Sb{sub 2}Te{sub 3} content x. When (Bi{sub 0.25}Sb{sub 0.75}){sub 2}Te{sub 3} was hot pressed at temperatures ranging from 300 C to 550 C for 30 minutes, figure-of-merit increased with hot pressing temperature and maximum value of 2.8 x 10{sup {minus}3}/K could be obtained by hot pressing at 550 C. When hot pressed at 550 C, (Bi{sub 0.2}Sb{sub 0.8}){sub 2}Te{sub 3} exhibited figure-of-merit of 2.92 x 10{sup {minus}3}/K, which could be improved to 2.97 x 10{sup {minus}3}/K with addition of 1 wt% Sb as acceptor dopant.

  11. Method of preparing (CH.sub.3).sub.3 SiNSO and byproducts thereof

    DOE Patents [OSTI]

    Spicer, Leonard D. (Salt Lake City, UT); Bennett, Dennis W. (Clemson, SC); Davis, Jon F. (Salt Lake City, UT)

    1984-01-01T23:59:59.000Z

    (CH.sub.3).sub.3 SiNSO is produced by the reaction of ((CH.sub.3).sub.3 Si).sub.2 NH with SO.sub.2. Also produced in the reaction are ((CH.sub.3).sub.3 Si).sub.2 O and a new solid compound [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ]. Both (CH.sub.3).sub.3 SiNSO and [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO.sub.2 pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH.sub.3).sub.3 Si).sub.2 NH, whereby any SO.sub.2 present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO.sub.2 in the original gas sample. The solid product [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] may be used as a standard in solid state NMR spectroscopy.

  12. Final Report: Northeastern Regional Center of the DOE's National Institute for Climatic Change Research

    SciTech Connect (OSTI)

    Davis, Kenneth

    2014-01-14T23:59:59.000Z

    Administration of the NERC of NICCR began at Penn State in December of 2005 and ended in December of 2011. During that time, five requests for proposals were released and five rounds of proposals were reviewed, awarded and administered. Throughout this award, 203 pre-proposals have been received by the NERC in five RFPS and 110 full proposals invited. Of the 110 full proposals reviewed, 53 were funded (most in full, some partially) resulting in 51 subcontracts. These awards were distributed among 17 universities and 3 non-governmental research institutes. Full proposals have been received from 29 universities and 5 non-governmental research institutes. Research activities have now been completed.

  13. Corona enhanced absorption of SO sub 2 /NO sub x

    SciTech Connect (OSTI)

    Dhali, S.K.

    1990-11-01T23:59:59.000Z

    This report contains results of an investigation of plasma-assisted oxidation of SO{sub 2} to SO{sub 3}. The SO{sub 3} is a more desirable by-product of flue gas than SO{sub 2} because it easily dissolves in water and can be reacted with lime to form gypsum. A coaxial dielectric-barrier discharge is used to generate an air plasma to carry out the reaction. The dielectric-barrier discharge,which is an interrupted discharge, is very efficient in producing atomic oxygen and requires a simple form of excitation. We have observed a significant reduction (over 75%) in the SO{sub 2} concentration using this technique. The simulation results indicate that about 99% of the SO{sub 2} can be oxidized with UV-irradiation along with plasma oxidation and that NO{sub x} can be reduced to N{sub 2} in the presence of an air plasma. The results of varying the gas composition, the gas pressure, and the gas flow are also reported. 18 refs., 8 figs.

  14. Distribution of cations in wurtzitic In<sub>xGa>1-xsub>N and In<sub>xAl>1-xsub>N alloys: Consequences for energetics and quasiparticle electronic structures

    SciTech Connect (OSTI)

    de Carvalho, Luiz Cláudio; Schleife, André; Furthmüller, Jürgen; Bechstedt, Friedhelm

    2012-03-01T23:59:59.000Z

    The ternary, isostructural, wurtzite-derived group-III mononitride alloys In<sub>xGa>1-xsub>N andIn<sub>xAl>1-xsub>N are reexamined within a cluster expansion approach. Using density functional theory together with the AM05 exchange-correlation functional, the total energies and the optimized atomic geometries of all 22 clusters classes of the cluster expansion for each material system are calculated. The computationally demanding calculation of the corresponding quasiparticle electronic structures is achieved for all cluster classes by means of a recently developed scheme to approximately solve the quasiparticle equation based on the HSE06 hybrid functional and the G?W? approach. Using two different alloy statistics, the configurational averages for the lattice parameters, the mixing enthalpies, and the bulk moduli are calculated. The composition-dependent electronic structures of the alloys are discussed based on configurationally averaged electronic states, band gaps, and densities of states. Ordered cluster arrangements are found to be energetically rather unfavorable, however, they possess the smallest energy gaps and, hence, contribute to light emission. The influence of the alloy statistics on the composition dependencies and the corresponding bowing parameters of the band gaps is found to be significant and should, hence, lead to different signatures in the optical-absorption or -emission spectra.

  15. Crystallographic, electronic, thermal, and magnetic properties of single-crystal SrCo<sub>2sub>As>2sub>

    SciTech Connect (OSTI)

    Pandey, Abhishek [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Quirinale, D. G. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Jayasekara, W. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Sapkota, A. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Kim, M. G. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dhaka, R. S. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Lee, Y. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Heitmann, T. W. [Univ. of Missouri, Columbia, MO (United States). Missouri Research Reactor; Stephens, P. W. [State Univ. of New York (SUNY), Plattsburgh, NY (United States); Ogloblichev, V. [Russian Academy of Sciences, Urals Div., Ekaterinburg (Russian Federation). Inst. of Metal Physics; Kreyssig, A. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; McQueeney, R. J. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Goldman, A. I. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Kaminski, Adam [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Harmon, B. N. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Furukawa, Y. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy; Johnston, D. C. [Ames Lab. and Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy

    2013-07-01T23:59:59.000Z

    In tetragonal SrCo<sub>2sub>As>2 sub>single crystals, inelastic neutron scattering measurements demonstrated that strong stripe-type antiferromagnetic (AFM) correlations occur at a temperature T = 5 K [W. Jayasekara et al., arXiv:1306.5174] that are the same as in the isostructural AFe<sub>2sub>As>2sub> (A = Ca, Sr, Ba) parent compounds of high-T<sub>c> superconductors. This surprising discovery suggests that SrCo<sub>2sub>As>2sub> may also be a good parent compound for high-T<sub>c sub>superconductivity. Here, structural and thermal expansion, electrical resistivity ?, angle-resolved photoemission spectroscopy (ARPES), heat capacity C<sub>p>, magnetic susceptibility ?, 75As NMR and neutron diffraction measurements of SrCo<sub>2sub>As>2sub> crystals are reported together with LDA band structure calculations that shed further light on this fascinating material. The c-axis thermal expansion coefficient ?<sub>c> is negative from 7 to 300 K, whereas ?<sub>a> is positive over this T range. The ?(T) shows metallic character. The ARPES measurements and band theory confirm the metallic character and in addition show the presence of a flat band near the Fermi energy E<sub>F>. The band calculations exhibit an extremely sharp peak in the density of states D(E<sub>F>) arising from a flat d<sub>x2-y2sub> band. A comparison of the Sommerfeld coefficient of the electronic specific heat with ?(T ? 0) suggests the presence of strong ferromagnetic itinerant spin correlations which on the basis of the Stoner criterion predicts that SrCo<sub>2sub>As>2sub> should be an itinerant ferromagnet, in conflict with the magnetization data. The ?(T) does have a large magnitude, but also exhibits a broad maximum at 115 K suggestive of dynamic short-range AFM spin correlations, in agreement with the neutron scattering data. The measurements show no evidence for any type of phase transition between 1.3 and 300 K and we propose that metallic SrCo<sub>2sub>As>2sub> has a gapless quantum spin-liquid ground state.

  16. Measurement of the ?<sub>b>? lifetime in the exclusive decay ?<sub>b>??J/??? in pp? collisions at ?s=1.96 TeV

    SciTech Connect (OSTI)

    Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Aoki, M.; Askew, A.; Atkins, S.; Augsten, K.; Avila, C.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bose, T.; Brandt, A.; Brandt, O.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Brown, J.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Buszello, C. P.; Camacho-Pérez, E.; Casey, B. C. K.; Castilla-Valdez, H.; Caughron, S.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Chevalier-Théry, S.; Cho, D. K.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Croc, A.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dubey, A.; Dudko, L. V.; Duggan, D.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Facini, G.; Feng, L.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garcia-Bellido, A.; García-González, J. A.; García-Guerra, G. A.; Gavrilov, V.; Gay, P.; Geng, W.; Gerbaudo, D.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Golovanov, G.; Goussiou, A.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hagopian, S.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Howley, I.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jayasinghe, A.; Jesik, R.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kaadze, K.; Kajfasz, E.; Karmanov, D.; Kasper, P. A.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kiselevich, I.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kulikov, S.; Kumar, A.; Kupco, A.; Kur?a, T.; Kuzmin, V. A.; Lammers, S.; Landsberg, G.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lellouch, J.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, H.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Lubatti, H. J.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Maravin, Y.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Mulhearn, M.; Nagy, E.; Naimuddin, M.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nunnemann, T.; Obrant, G.; Orduna, J.; Osman, N.; Osta, J.; Padilla, M.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Pleier, M.-A.; Podesta-Lerma, P. L. M.; Podstavkov, V. M.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Quadt, A.; Quinn, B.; Rangel, M. S.; Ranjan, K.; Ratoff, P. N.; Razumov, I.; Renkel, P.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Sajot, G.; Salcido, P.; Sánchez-Hernández, A.; Sanders, M. P.; Sanghi, B.; Santos, A. S.; Savage, G.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schlobohm, S.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shaw, S.; Shchukin, A. A.; Shivpuri, R. K.; Simak, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Smith, K. J.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Soustruznik, K.; Stark, J.; Stoyanova, D. A.; Strauss, M.; Stutte, L.; Suter, L.; Svoisky, P.; Takahashi, M.; Titov, M.; Tokmenin, V. V.; Tsai, Y.-T.; Tschann-Grimm, K.; Tsybychev, D.; Tuchming, B.; Tully, C.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.

    2012-06-01T23:59:59.000Z

    We measure the ??<sub>b> lifetime in the fully reconstructed decay ??<sub>b>?J/??? using 10.4 fb?¹ of pp? collisions collected with the D0 detector at ?s=1.96 TeV. The lifetime of the topologically similar decay channel B??J/?K?<sub>S> is also measured. We obtain ?(??<sub>b>)=1.303±0.075(stat)±0.035(syst) ps and ?(B?)=1.508±0.025(stat)±0.043(syst) ps. Using these measurements, we determine the lifetime ratio of ?(??<sub>b>)/?(B?)=0.864±0.052(stat)±0.033(syst).

  17. Correlation between upconversion photoluminescence and dielectric response in Ba-substituted (Sr{sub 1?x}Ba{sub x}){sub 4}(La{sub 0.85}Ho{sub 0.025}Yb{sub 0.125}){sub 2}Ti{sub 4}Nb{sub 6}O{sub 30}

    SciTech Connect (OSTI)

    Wei, T., E-mail: weitong.nju@gmail.com [College of Science, Civil Aviation University of China, Tianjin 300300 (China); Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Wang, X. D. [College of Science, Civil Aviation University of China, Tianjin 300300 (China); Zhao, C. Z. [School of Electronics and Information Engineering, Tianjin Polytechnic University, Tianjin 300160 (China); Liu, M. F.; Liu, J. M., E-mail: liujm@nju.edu.cn [Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China)

    2014-06-30T23:59:59.000Z

    The filled tetragonal tungsten bronze (Sr{sub 1?x}Ba{sub x}){sub 4}(La{sub 0.85}Ho{sub 0.025}Yb{sub 0.125}){sub 2}Ti{sub 4}Nb{sub 6}O{sub 30} (SBLTNx: Ho-Yb) ceramics with different Ba substitution levels (x) are prepared. The upconversion photoluminescence (UC-PL) and dielectric permittivity are investigated. The substitution of Sr{sup 2+} ions at the A{sub 2}-sites by larger Ba{sup 2+} ions results in substantial variation of the UC-PL intensity as a function of substitution level x. Furthermore, the dielectric response to the substitution of Sr{sup 2+} by Ba{sup 2+} suggests a close correlation between the UC-PL intensity and dielectric permittivity. The origin for this correlation is discussed based on the random stress field (RSF) model.

  18. Electronic structure and bonding in garnet crystals Gd{sub 3}Sc{sub 2}Ga{sub 3}O{sub 12}, Gd{sub 3}Sc{sub 2}Al{sub 3}O{sub 12}, and Gd{sub 3}Ga{sub 3}O{sub 12} compared to Y{sub 3}Al{sub 3}O{sub 12}

    SciTech Connect (OSTI)

    Xu, Yong-Nian [Department of Physics, University of Missouri-Kansas City, Kansas City, Missouri 64110 (United States)] [Department of Physics, University of Missouri-Kansas City, Kansas City, Missouri 64110 (United States); Ching, W. Y. [Department of Physics, University of Missouri-Kansas City, Kansas City, Missouri 64110 (United States)] [Department of Physics, University of Missouri-Kansas City, Kansas City, Missouri 64110 (United States); Brickeen, B. K. [Allied Signal FM and T, Kansas City, Missouri 64141 (United States)] [Allied Signal FM and T, Kansas City, Missouri 64141 (United States)

    2000-01-15T23:59:59.000Z

    The electronic structure and bonding of Gd{sub 3}Sc{sub 2}Ga{sub 3}O{sub 12} (GSGG), Gd{sub 3}Sc{sub 2}Al{sub 3}O{sub 12} (GSAG), and Gd{sub 3}Ga{sub 5}O{sub 12} (GGG) crystals with a garnet structure are studied by means of first-principles local-density calculations. The results are compared with a similar calculation on yttrium aluminum garnet [Y{sub 3}Al{sub 5}O{sub 12} (YAG)]. The calculated equilibrium volumes of the three crystals are close to the measured volumes with a slight overestimation for GGG. GGG also has a smaller bulk modulus than the other three crystals. The calculated density of states and their atomic and orbital decompositions are presented and contrasted. All four crystals show very similar band structures and interatomic bonding. However, it is found that in GSGG and GSAG crystals, the Sc atom at the octahedral site shows a higher covalent character and an increased bond order in comparison to Ga or Al at the same site. This result may provide some insight into the significant difference in the radiation hardness of Cr{sup 3+}:Nd{sup 3+}:GSGG as compared to Nd{sup 3+}:YAG. (c) 2000 The American Physical Society.

  19. Combined SO sub 2 /NO sub x reduction technology

    SciTech Connect (OSTI)

    Livengood, C.D.; Huang, H.S. (Argonne National Lab., IL (United States)); Markussen, J.M. (USDOE Pittsburgh Energy Technology Center, PA (United States))

    1992-01-01T23:59:59.000Z

    Enactment of the Clean Air Act Amendments and passage of state legislation leading to more stringent nitrogen oxides (NO{sub x}) regulations have fueled research and development efforts on technologies for the combined control of sulfur dioxide (SO{sub 2}) and NO{sub x}. The integrated removal of both SO{sub 2} and NO{sub x}, in a single system can offer significant advantages over the use of several separate processes, including such factors as reduced system complexity, better operability, and lower costs. This paper reviews the status of a number of integrated flue-gas-cleanup (FGC) systems that have reached a significant stage of development, focusing on post-combustion processes that have been tested or are ready for testing at the pilot scale or larger. A brief process description, a summary of the development status and performance achieved to date, pending commercialization issues, and process economics (when available) are given for each technology.

  20. DISSOCIATIVE RECOMBINATION OF VIBRATIONALLY COLD CH{sup +}{sub 3} AND INTERSTELLAR IMPLICATIONS

    SciTech Connect (OSTI)

    Thomas, R. D.; Kashperka, I.; Vigren, E.; Geppert, W. D.; Hamberg, M.; Larsson, M.; Af Ugglas, M.; Zhaunerchyk, V. [Department of Physics, Stockholm University, Albanova University Centre, SE-106 91 Stockholm (Sweden); Indriolo, N. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Yagi, K.; Hirata, S. [Department of Chemistry, University of Illinois, Urbana, IL 61801 (United States); McCall, B. J., E-mail: rdt@fysik.su.se [Departments of Chemistry, Astronomy, and Physics, University of Illinois, Urbana, IL 61801 (United States)

    2012-10-10T23:59:59.000Z

    CH{sup +}{sub 3} is an important molecular ion in the astrochemistry of diffuse clouds, dense clouds, cometary comae, and planetary ionospheres. However, the rate of one of the major destruction mechanisms of CH{sup +}{sub 3}, dissociative recombination (DR), has long been uncertain, hindering the use of CH{sup +}{sub 3} as an astrochemical probe. Here, we present the first absolute measurement of the DR of vibrationally cold CH{sup +}{sub 3}, which has been made using the heavy storage ring CRYRING in Stockholm, Sweden. From our collision-energy-dependent cross sections, we infer a thermal rate constant of k(T) = 6.97({+-} 0.03) Multiplication-Sign 10{sup -7}(T/300){sup -0.61({+-}0.01)} cm{sup 3} s{sup -1} over the region 10 K {<=} T {<=} 1000 K. At low collision energies, we have measured the branching fractions of the DR products to be CH{sub 3} (0.00{sup +0.01}{sub -0.00}), CH{sub 2} + H (0.35{sup +0.01}{sub -0.01}), CH + 2H (0.20{sup +0.02}{sub -0.02}), CH + H{sub 2} (0.10{sup +0.01}{sub -0.01}), and C + H{sub 2} + H (0.35{sup +0.01}{sub -0.02}), indicating that two or more C-H bonds are broken in 65% of all collisions. We also present vibrational calculations which indicate that the CH{sup +}{sub 3} ions in the storage ring were relaxed to the vibrational ground state by spontaneous emission during the storage time. Finally, we discuss the implications of these new measurements for the observation of CH{sup +}{sub 3} in regions of the diffuse interstellar medium where CH{sup +} is abundant.

  1. Interfacial chemistry and valence band offset between GaN and Al{sub 2}O{sub 3} studied by X-ray photoelectron spectroscopy

    SciTech Connect (OSTI)

    Duan, T. L.; Ang, D. S. [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)] [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Pan, J. S. [Institute of Materials Research and Engineering, A-STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602 (Singapore)] [Institute of Materials Research and Engineering, A-STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602 (Singapore)

    2013-05-20T23:59:59.000Z

    The interface region between Ga-face n-type GaN and Al{sub 2}O{sub 3} dielectric (achieved via atomic-layer deposition or ALD) is investigated by X-ray photoelectron spectroscopy (XPS). An increase in the Ga-O to Ga-N bond intensity ratio following Al{sub 2}O{sub 3} deposition implies that the growth of an interfacial gallium sub-oxide (GaO{sub x}) layer occurred during the ALD process. This finding may be ascribed to GaN oxidation, which may still happen following the reduction of a thin native GaO{sub x} by trimethylaluminum (TMA) in the initial TMA-only cycles. The valence band offset between GaN and Al{sub 2}O{sub 3}, obtained using both core-level and valence band spectra, is found to vary with the thickness of the deposited Al{sub 2}O{sub 3}. This observation may be explained by an upward energy band bending at the GaN surface (due to the spontaneous polarization induced negative bound charge on the Ga-face GaN) and the intrinsic limitation of the XPS method for band offset determination.

  2. Li{sub 2}B{sub 3}O{sub 4}F{sub 3}, a new lithium-rich fluorooxoborate

    SciTech Connect (OSTI)

    Pilz, Thomas; Nuss, Hanne [Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart (Germany); Jansen, Martin, E-mail: M.Jansen@fkf.mpg.de [Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart (Germany)

    2012-02-15T23:59:59.000Z

    The new lithium fluorooxoborate, Li{sub 2}B{sub 3}O{sub 4}F{sub 3}, is obtained by a solid state reaction from LiBO{sub 2} and LiBF{sub 4} at 553 K and crystallizes in the acentric orthorhombic space group P2{sub 1}2{sub 1}2{sub 1} (no. 19) with the cell parameters a=4.8915(9), b=8.734(2), and c=12.301(2) A. Chains of fluorinated boroxine rings along the b axis consists of BO{sub 3} triangles and BO{sub 2}F{sub 2} as well as BO{sub 3}F tetrahedra. Mobile lithium ions are compensating the negative charge of the anionic chain, in which the fourfold coordinated boron atoms bear a negative formal charge. Annealing Li{sub 2}B{sub 3}O{sub 4}F{sub 3} at temperatures above 573 K leads to conversion into Li{sub 2}B{sub 6}O{sub 9}F{sub 2}. The title compound is an ionic conductor with the highest ion conductivity among the hitherto know lithium fluorooxoborates, with conductivities of 1.6 Multiplication-Sign 10{sup -9} and 1.8 Multiplication-Sign 10{sup -8} S cm{sup -1} at 473 and 523 K, respectively. - Graphical abstract: Repetition unit of Li{sub 2}B{sub 3}O{sub 4}F{sub 3}. Highlights: Black-Right-Pointing-Pointer Li{sub 2}B{sub 3}O{sub 4}F{sub 3} is the third member within the family of lithium fluorooxoborates. Black-Right-Pointing-Pointer It shows the highest lithium ion conductivity among them. Black-Right-Pointing-Pointer Chains of interconnected fluorinated boroxine rings run along the b axis. Black-Right-Pointing-Pointer Acentric space group meets the requirement for second harmonic generation.

  3. Ab initio study of irradiation tolerance for different M{sub n+1}AX{sub n} phases: Ti{sub 3}SiC{sub 2} and Ti{sub 3}AlC{sub 2}

    SciTech Connect (OSTI)

    Zhao, Shijun; Xue, Jianming, E-mail: jmxue@pku.edu.cn; Wang, Yugang [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Center for Applied Physics and Technology, Peking University, Beijing 100871 (China); Huang, Qing [Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, Zhejiang (China)

    2014-01-14T23:59:59.000Z

    Layered ternary M{sub n+1}AX{sub n} (MAX) materials are recently proposed to be promising candidates for future fission and fusion programmes because of their unique properties inherited from both ceramics and metals. However, different M{sub n+1}AX{sub n} materials demonstrate different behaviors when exposed to energetic neutron or ion irradiations. Based on first-principles calculations, we have investigated the irradiation tolerance of two typical M{sub n+1}AX{sub n} materials: Ti{sub 3}SiC{sub 2} and Ti{sub 3}AlC{sub 2} from two aspects. First, we make a detailed analysis on the interatomic bonding characters, which are believed to be responsible for the resistance to radiation-induced amorphization. Second, the formation energies of various intrinsic and antisite defects in these two compounds are calculated in order to elucidate their amorphization mechanism. Our results show that the absence of orbitals overlap of Al-C in Ti{sub 3}AlC{sub 2} renders it more resistant to amorphization compared to Ti{sub 3}SiC{sub 2}. In addition, the antisite defects Al{sub Ti(1)} and Al{sub Ti(2)} in Ti{sub 3}AlC{sub 2} have much lower formation energies compared to Si{sub Ti(1)} and Si{sub Ti(2)} in Ti{sub 3}SiC{sub 2}, which implies that the replacement of Ti with Al is easier than Si, thus providing an alternative way to accommodate the defects resulted from irradiation damage cascades. These results indicate that Ti{sub 3}AlC{sub 2} is more irradiation tolerant than Ti{sub 3}SiC{sub 2}, in accordance with experimental observations. Our results have profound implications for the choice of appropriate MAX phase with best performance to be used in next reaction reactors.

  4. Structural and magnetic properties and superconductivity in Ba(Fe{sub 1-x}TM{sub x}){sub 2}As{sub 2}

    SciTech Connect (OSTI)

    Thaler, Alexander

    2012-07-23T23:59:59.000Z

    We studied the effects on structural and magnetic phase transitions and the emergence of superconductivity in transition metal substituted BaFe{sub 2}As{sub 2}. We grew four series of Ba(Fe{sub 1-x}TM{sub x}){sub 2}As{sub 2} (TM=Ru, Mn, Co+Cr and Co+Mn) and characterized them by crystallographic, magnetic and transport measurements. We also subjected Ba(Fe{sub 1-x}Cr{sub x}){sub 2}As{sub 2} and Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} to heat treatment to explore what changes might be induced.

  5. Exchange integrals in magnetoelectric hexagonal ferrite (SrCo{sub 2}Ti{sub 2}Fe{sub 8}O{sub 19}): A density functional study

    SciTech Connect (OSTI)

    Feng, Min [School of Physics, Nankai University, Tianjin 300071 (China); Shao, Bin [Department of Physics, Tsinghua University, Beijing 100084 (China); Lu, Yuan; Zuo, Xu, E-mail: xzuonku@gmail.com [College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300071 (China)

    2014-05-07T23:59:59.000Z

    The exchange integrals in magnetoelectric hexagonal ferrite SrCo{sub 2}Ti{sub 2}Fe{sub 8}O{sub 19} have been calculated by using density functional theory. To get 10 inter-sublattice and 3 intra-sublattice exchange integrals, the electronic structures and total energies of 20 spin arrangements have been calculated with General Gradient Approximation (GGA) + U method. The dependence of exchange integrals on U has been studied. The comparison between the exchange integrals in SrFe{sub 12}O{sub 19} and those in SrCo{sub 2}Ti{sub 2}Fe{sub 8}O{sub 19} shows that substitution of Co and Ti decreases the most interactions involving the 12?k sites. The investigation based on our exchange integrals indicates that magnetic interaction between R and S blocks reduces significantly in SrCo{sub 2}Ti{sub 2}Fe{sub 8}O{sub 19}.

  6. Hydrothermal synthesis and luminescent properties of NaLa(MoO{sub 4}){sub 2}:Dy{sup 3+} phosphor

    SciTech Connect (OSTI)

    Li Linlin; Zi Wenwen; Li Guanghuan; Lan Shi; Ji Guijuan [College of Chemistry, Jilin University, Changchun 130026 (China); Gan Shucai, E-mail: gansc@jlu.edu.cn [College of Chemistry, Jilin University, Changchun 130026 (China); Zou Haifeng [College of Chemistry, Jilin University, Changchun 130026 (China); Xu Xuechun [College of Earth Sciences, Jilin University, Changchun 130026 (China)

    2012-07-15T23:59:59.000Z

    Pompon-like NaLa(MoO{sub 4}){sub 2}:Dy{sup 3+} phosphors have been successfully prepared via a hydrothermal method using ammonia as pH value regulator. The hydrothermal process was carried out under aqueous condition without the use of any organic solvent, surfactant, and catalyst. The experimental results demonstrate that the obtained NaLa(MoO{sub 4}){sub 2}:Dy{sup 3+} phosphor powders are single-phase scheelite structure with tetragonal symmetry. Moreover, the phosphor under the excitation of 390 and 456 nm exhibited blue emission (486 nm) and yellow emission (574 nm), corresponding to the {sup 4}F{sub 9/2}{yields}{sup 6}H{sub 15/2} transition and {sup 4}F{sub 9/2}{yields}{sup 6}H{sub 13/2} transition of Dy{sup 3+} ions, respectively. In addition, the yellow-to-blue emission intensity ratio (Y/B) can be changed with the doped concentration of Dy{sup 3+} ions. All chromaticity coordinates of the obtained NaLa(MoO{sub 4}){sub 2}:Dy{sup 3+} phosphors are located in the white-light region. The results indicate that this kind of phosphor may has potential applications in the fields of near UV-excited and blue-excited white LEDs. - Graphical abstract: It can be seen from the SEM images that a pompon-like shape was obtained with an average diameter of about 1 {mu}m, and it is composed of many nanoflakes. Highlights: Black-Right-Pointing-Pointer Pompon-like NaLa(MoO{sub 4}){sub 2}:Dy{sup 3+} phosphors have been successfully prepared via a hydrothermal method. Black-Right-Pointing-Pointer Blue emission at 486 nm and yellow emission at 574 nm were obtained from the samples. Black-Right-Pointing-Pointer The yellow-to-blue emission intensity ratio (Y/B) can be changed with the doped concentration of Dy{sup 3+} ions. Black-Right-Pointing-Pointer NaLa(MoO{sub 4}){sub 2}:Dy{sup 3+} can be efficiently excited by the blue light and the near ultraviolet light.

  7. Microwave electrode discharge in nitrogen: Structure and characteristics of the electrode region

    SciTech Connect (OSTI)

    Lebedev, Yu. A.; Solomakhin, P. V.; Shakhatov, V. A. [Russian Academy of Sciences, Topchiev Institute of Petrochemical Synthesis (Russian Federation)

    2008-07-15T23:59:59.000Z

    The parameters of the electrode region of an electrode microwave discharge in nitrogen are studied by emission spectroscopy. The radial and axial distributions of the intensities of the bands of the second (N{sub 2}(C{sup 3{Pi}}{sub u} {sup {yields}}B{sup 3{Pi}}{sub g})) and first (N{sub 2}(B{sup 3{Pi}}{sub g} {sup {yields}}A{sup 3{Sigma}}{sub u}{sup +})) positive systems of molecular nitrogen and the first negative system of nitrogen ions (N{sub 2}{sup +} (B{sup 2{Sigma}}{sub u}{sup +} {sup {yields}}X{sup 2{Sigma}}{sub g}{sup +})), the radial profiles of the electric field E and the electron density N{sub e}, and the absolute populations of the vibrational levels v{sub C} = 0-4 of the C{sup 3{Pi}}{sub u} excited state of N{sub 2} and the vibrational level v{sub Bi} = 0 of the B{sup 2{Sigma}}{sub u}{sup +} excited state of a molecular nitrogen ion are determined. The population temperature of the first vibrational level T{sub V} of the ground electronic state X{sup 1{Sigma}}{sub g}{sup +} of N{sub 2} and the excitation temperature T{sub C} of the C{sup 3{Pi}}{sub u} state in the electrode region of the discharge are measured. The radius of the spherical region and the spatially integrated plasma emission spectra are studied as functions of the incident microwave power and gas pressure. A method for determining the electron density and the microwave field strength from the plasma emission characteristics is described in detail.

  8. Optically pumped cerium-doped LiSrAlF{sub 6} and LiCaAlF{sub 6}

    DOE Patents [OSTI]

    Marshall, C.D.; Payne, S.A.; Krupke, W.F.

    1996-05-14T23:59:59.000Z

    Ce{sup 3+}-doped LiSrAlF{sub 6} crystals are pumped by ultraviolet light which is polarized along the c axis of the crystals to effectively energize the laser system. In one embodiment, the polarized fourth harmonic light output from a conventional Nd:YAG laser operating at 266 nm is arranged to pump Ce:LiSrAlF{sub 6} with the pump light polarized along the c axis of the crystal. The Ce:LiSrAlF{sub 6} crystal may be placed in a laser cavity for generating tunable coherent ultraviolet radiation in the range of 280-320 nm. Additionally, Ce-doped crystals possessing the LiSrAlF{sub 6} type of chemical formula, e.g. Ce-doped LiCaAlF{sub 6} and LiSrGaF{sub 6}, can be used. Alternative pump sources include an ultraviolet-capable krypton or argon laser, or ultraviolet emitting flashlamps. The polarization of the pump light will impact operation. The laser system will operate efficiently when light in the 280-320 nm gain region is injected or recirculated in the system such that the beam is also polarized along the c axis of the crystal. The Ce:LiSrAlF{sub 6} laser system can be configured to generate ultrashort pulses, and it may be used to pump other devices, such as an optical parametric oscillator. 10 figs.

  9. Optically pumped cerium-doped LiSrAlF.sub.6 and LiCaAlF.sub.6

    DOE Patents [OSTI]

    Marshall, Christopher D. (Livermore, CA); Payne, Stephen A. (Castro Valley, CA); Krupke, William F. (Pleasanton, CA)

    1996-01-01T23:59:59.000Z

    Ce.sup.3+ -doped LiSrAlF.sub.6 crystals are pumped by ultraviolet light which is polarized along the c axis of the crystals to effectively energize the laser system. In one embodiment, the polarized fourth harmonic light output from a conventional Nd:YAG laser operating at 266 nm is arranged to pump Ce:LiSrAlF.sub.6 with the pump light polarized along the c axis of the crystal. The Ce:LiSrAlF.sub.6 crystal may be placed in a laser cavity for generating tunable coherent ultraviolet radiation in the range of 280-320 nm. Additionally, Ce-doped crystals possessing the LiSrAlF.sub.6 type of chemical formula, e.g. Ce-doped LiCaAlF.sub.6 and LiSrGaF.sub.6, can be used. Alternative pump sources include an ultraviolet-capable krypton or argon laser, or ultraviolet emitting flashlamps. The polarization of the pump light will impact operation. The laser system will operate efficiently when light in the 280-320 nm gain region is injected or recirculated in the system such that the beam is also polarized along the c axis of the crystal. The Ce:LiSrAlF.sub.6 laser system can be configured to generate ultrashort pulses, and it may be used to pump other devices, such as an optical parametric oscillator.

  10. Method for making graded I-III-VI.sub.2 semiconductors and solar cell obtained thereby

    DOE Patents [OSTI]

    Devaney, Walter E. (Seattle, WA)

    1987-08-04T23:59:59.000Z

    Improved cell photovoltaic conversion efficiencies are obtained by the simultaneous elemental reactive evaporation process of Mickelsen and Chen for making semiconductors by closer control of the evaporation rates and substrate temperature during formation of the near contact, bulk, and near junction regions of a graded I-III-VI.sub.2, thin film, semiconductor, such as CuInSe.sub.2 /(Zn,Cd)S or another I-III-VI.sub.2 /II-VI heterojunction.

  11. Low NO sub x /SO sub x Burner retrofit for utility cyclone boilers

    SciTech Connect (OSTI)

    Not Available

    1990-01-01T23:59:59.000Z

    Cyclone furnaces operate with high excess air and at high temperature. The heat release during combustion is very high and as a result the boiler volume is much smaller than would be found in a conventional pc-fired system. The Marion Unit 1 boiler, at the level of the cyclone entry, has a small cross-section; about 5-feet in depth and about 20-feet in width. A boiler schematic showing the LNS Burner and relative location of the superheater region and overfire air ports is shown in Figure 1. The LNS Burner's combustion process is fundamentally different from that of the cyclone, and the combustion products are also different. The LNS Burner products enter the boiler as hot, fuel-rich gases. Additional overfire air must be added to complete this combustion step with care taken to avoid the formation of thermal NO{sub x}. If done correctly, S0{sub 2} is controlled and significant NO{sub x} reductions are achieved. Because of the small boiler volume, flow modelling was found to be necessary to insure that adequate mixing of LNS Burner combustion products with air can be accomplished to achieve NO{sub x} emissions goals. Design requirements for the air injection system for the Marion boiler were developed using FLUENT, a commercially available computational fluid dynamics (CFD) code. A series of runs were made to obtain a design for final air injection that met the process design goals as closely as possible.

  12. Improved Search for ??<sub>????e> Oscillations in the MiniBooNE Experiment

    SciTech Connect (OSTI)

    Aguilar-Arevalo, A. A.; Brown, B. C.; Bugel, L.; Cheng, G.; Church, E. D.; Conrad, J. M.; Dharmapalan, R.; Djurcic, Z.; Finley, D. A.; Ford, R.; Garcia, F. G.; Garvey, G. T.; Grange, J.; Huelsnitz, W.; Ignarra, C.; Imlay, R.; Johnson, R. A.; Karagiorgi, G.; Katori, T.; Kobilarcik, T.; Louis, W. C.; Mariani, C.; Marsh, W.; Mills, G. B.; Mirabal, J.; Moore, C. D.; Mousseau, J.; Nienaber, P.; Osmanov, B.; Pavlovic, Z.; Perevalov, D.; Polly, C. C.; Ray, H.; Roe, B. P.; Russell, A. D.; Shaevitz, M. H.; Spitz, J.; Stancu, I.; Tayloe, R.; Van de Water, R. G.; White, D. H.; Wickremasinghe, D. A.; Zeller, G. P.; Zimmerman, E. D.

    2013-04-01T23:59:59.000Z

    The MiniBooNE experiment at Fermilab reports results from an analysis of ?¯<sub>e> appearance data from 11.27×10²? protons on target in the antineutrino mode, an increase of approximately a factor of 2 over the previously reported results. An event excess of 78.4±28.5 events (2.8?) is observed in the energy range 200QE<sub>?><1250 MeV. If interpreted in a two-neutrino oscillation model, ?¯<sub>???¯e>, the best oscillation fit to the excess has a probability of 66% while the background-only fit has a ?² probability of 0.5% relative to the best fit. The data are consistent with antineutrino oscillations in the 0.01

  13. Synthesis and X-ray structural investigation of K{sub 8}[(UO{sub 2}){sub 2}(C{sub 2}O{sub 4}){sub 2}(SeO{sub 4}){sub 4}] . 2H{sub 2}O

    SciTech Connect (OSTI)

    Serezhkina, L. B., E-mail: lserezh@ssu.samara.ru [Samara State University (Russian Federation); Peresypkina, E. V.; Virovets, A. V. [Russian Academy of Sciences, Nikolaev Institute of Inorganic Chemistry, Siberian Branch (Russian Federation); Verevkin, A. G.; Pushkin, D. V. [Samara State University (Russian Federation)

    2009-01-15T23:59:59.000Z

    Single crystals of the compound K{sub 8}[(UO{sub 2}){sub 2}(C{sub 2}O{sub 4}){sub 2}(SeO{sub 4})4] . 2H{sub 2}O (I) are synthesized, and their structure is investigated using X-ray diffraction. Compound I crystallizes in the monoclinic system with the unit cell parameters a = 14.9290(4) A, b = 7.2800(2) A, c = 15.3165(4) A, {beta} = 109.188(1){sup o}, V = 1572.17(7) A{sup 3}, space group P2{sub 1}/n, Z = 2, and R = 0.0297. The uranium-containing structural units of crystals I are dimers of the composition [(UO {sub 2}){sub 2}(C{sub 2}O{sub 4}){sub 2}(SeO{sub 4}){sub 4}]{sup 8-}, which belong to the crystal-chemical group AB{sup 01}B{sup 2}M{sup 1} (A = UO{sub 2}{sup 2+}, B{sup 01} = C{sub 2}O{sub 4}{sup 2-}, B{sup 2} = SeO{sub 4}{sup 2-}, M{sup 1} = SeO{sub 4}{sup 2-}) of the uranyl complexes. The [(UO{sub 2}){sub 2}(C{sub 2}O{sub 4}){sub 2}(SeO{sub 4}){sub 4}]{sup 8-} dimers are joined into a three-dimensional framework through electrostatic interactions with the outer-sphere potassium cations.

  14. Bifunctional Fe{sub 3}O{sub 4}@Gd{sub 2}O{sub 3}:Eu{sup 3+}nanocomposites obtained by the homogeneous precipitation method

    SciTech Connect (OSTI)

    Peng, Hongxia [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry (Ministry of Education), Shanxi Key Laboratory of Physico-Inorganic Chemistry, School of Chemistry and Materials Science, Northwest University, Xi’an, Shanxi 710069 (China); Cui, Bin, E-mail: cuibin@nwu.edu.cn [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry (Ministry of Education), Shanxi Key Laboratory of Physico-Inorganic Chemistry, School of Chemistry and Materials Science, Northwest University, Xi’an, Shanxi 710069 (China); Wang, Yingsai [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry (Ministry of Education), Shanxi Key Laboratory of Physico-Inorganic Chemistry, School of Chemistry and Materials Science, Northwest University, Xi’an, Shanxi 710069 (China)

    2013-05-15T23:59:59.000Z

    Graphical abstract: The TEM images reveal clearly the core–shell structures because of the obvious difference in contrast between the central part and the fringe, which indicates the Gd{sub 2}O{sub 3}:Eu{sup 3+} layer had successfully deposited on the magnetite Fe{sub 3}O{sub 4} cores. And Fe{sub 3}O{sub 4}@Gd{sub 2}O{sub 3}:Eu{sup 3+} nanoparticles keep the spherical morphology, non-aggregation and rough surface. The images reveal that the average diameters of the Fe{sub 3}O{sub 4} and Fe{sub 3}O{sub 4}@Gd{sub 2}O{sub 3}:Eu{sup 3+} nanoparticles are ?200 nm and ?250 nm, respectively. The thickness of Gd{sub 2}O{sub 3}:Eu{sup 3+} layer is ?25 nm. Highlights: ? Fe{sub 3}O{sub 4}@Gd{sub 2}O{sub 3}:Eu{sup 3+} nanocomposites were synthesized by homogeneous precipitation method. ? Formation of core–shell nanostructure revealed by transmission electron microscopy. ? Fe{sub 3}O{sub 4}@Gd{sub 2}O{sub 3}:Eu{sup 3+} nanocomposites showed magnetic behavior and fluorescence properties. ? Possible applications including bioseparation, drug delivery system, bio-labels, etc. - Abstract: An easy homogeneous precipitation method was developed for the synthesis of bifunctional magnetic-fluorescent nanocomposites with Fe{sub 3}O{sub 4} nanoparticles as the core and europium-doped gadolinium oxide (Gd{sub 2}O{sub 3}:Eu{sup 3+}) as the shell. The nanocomposites showed both strong magnetic behavior and unique Eu-related fluorescence properties with a high emission intensity, which may lead to development of nanocomposites with great potential for applications in drug targeting, biosensors, and diagnostic analysis.

  15. Crystal structure and electric properties of the organic–inorganic hybrid: [(CH{sub 2}){sub 6}(NH{sub 3}){sub 2}]ZnCl{sub 4}

    SciTech Connect (OSTI)

    Mostafa, M.F., E-mail: Mohga40@Yahoo.com; El-khiyami, S.S.

    2014-01-15T23:59:59.000Z

    The new organic-inorganic hybrid [(CH{sub 2}){sub 6}(NH{sub 3}){sub 2}]ZnCl{sub 4}, M{sub r}=325.406 crystallized in a triclinic, P1¯, a=7.2816 (5) Å, b=10.0996 (7) Å, c=10.0972 (7) Å, ?=74.368 (4)°, ?=88.046 (4)°, ?=85.974 (3)°, V=713.24 (9) Å{sup 3} and Z=2, D{sub x}=1.486 Mg m{sup ?3}. Differential thermal scanning and x-ray powder diffraction, permittivity and ac conductivity indicated three phase transitions. Conduction takes place via correlated barrier hopping. - Graphical abstract: Display Omitted.

  16. B{sub s{yields}}f{sub 0}(980) form factors and B{sub s} decays into f{sub 0}(980)

    SciTech Connect (OSTI)

    Colangelo, Pietro; De Fazio, Fulvia; Wang Wei [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Via Orabona 4, I-70126 Bari (Italy)

    2010-04-01T23:59:59.000Z

    We compute the B{sub s{yields}}f{sub 0}(980) transition form factors using light-cone QCD sum rules at leading order in the strong coupling constant, and also including an estimate of next-to-leading order corrections. We use the results to predict the branching fractions of the rare decay modes B{sub s{yields}}f{sub 0}l{sup +}l{sup -} and B{sub s{yields}}f{sub 0{nu}{nu}}, which turn out to be O(10{sup -7}) (B{sub s{yields}}f{sub 0}(980)l{sup +}l{sup -}, with l=e, {mu}), O(10{sup -8}) (B{sub s{yields}}f{sub 0}(980){tau}{sup +{tau}-}) and O(10{sup -6}) (B{sub s{yields}}f{sub 0}(980){nu}{nu}). We also predict the branching ratio of B{sub s{yields}}J/{psi}f{sub 0}(980) decay under the factorization assumption, and discuss the role of this channel for the determination of the B{sub s} mixing phase compared to the golden mode B{sub s{yields}}J/{psi}{phi}. As a last application, we consider D{sub s{yields}}f{sub 0} form factors, providing a determination of the branching ratio of D{sub s{yields}}f{sub 0}e{sup +{nu}}{sub e}.

  17. Structural investigation of the new Ca{sub 3}Ln{sub 2}Ge{sub 3}O{sub 12} (Ln=Pr, Nd, Sm, Gd and Dy) compounds and luminescence spectroscopy of Ca{sub 3}Gd{sub 2}Ge{sub 3}O{sub 12} doped with the Eu{sup 3+} ion

    SciTech Connect (OSTI)

    Piccinelli, F., E-mail: fabio.piccinelli@univr.it [Luminescent Materials Laboratory, DB, Univ. Verona, and INSTM, UdR Verona, Strada Le Grazie 15, 37134 Verona (Italy); Lausi, A. [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale 14-km 163,5 in AREA Science Park, 34149 Basovizza, Trieste (Italy); Bettinelli, M. [Luminescent Materials Laboratory, DB, Univ. Verona, and INSTM, UdR Verona, Strada Le Grazie 15, 37134 Verona (Italy)

    2013-09-15T23:59:59.000Z

    The crystal structures of new rare earth-based germanate compounds (Ca{sub 3}Pr{sub 2}Ge{sub 3}O{sub 12}, Ca{sub 3}Nd{sub 2}Ge{sub 3}O{sub 12}, Ca{sub 3}Sm{sub 2}Ge{sub 3}O{sub 12}, Ca{sub 3}Gd{sub 2}Ge{sub 3}O{sub 12} and Ca{sub 3}Dy{sub 2}Ge{sub 3}O{sub 12}) have been determined by Rietveld refinement calculations on the collected synchrotron X-ray diffraction powder patterns. A different distribution of the rare earth ions in the three available crystal sites was observed, as the main structural feature. The reasons of the instability of the silico-carnotite structure for lanthanide ions out of the range Pr–Dy have been proposed. Finally, the luminescence spectroscopy of the Eu{sup 3+} dopant ion in Ca{sub 3}Gd{sub 2}Ge{sub 3}O{sub 12} was presented and analyzed taking into account the observed structural characteristics. The Eu{sup 3+} luminescence spectroscopy was also compared with the one of Eu{sup 3+} doped Ca{sub 3}Gd{sub 2}Si{sub 3}O{sub 12} and Ca{sub 3}Lu{sub 2}Si{sub 3}O{sub 12} isostructural materials. - Graphical abstract: The structural study on Ca{sub 3}Ln{sub 2}Ge{sub 3}O{sub 12} exploiting synchrotron X-ray diffraction, allows us to determine the detailed geometry of the coordination polyhedra of the metals and their distribution in the crystal sites. These features are, in the case of Ca{sub 3}Gd{sub 2}Ge{sub 3}O{sub 12} host, closely related to the luminescence spectroscopy of the Eu{sup 3+} dopant ion. Display Omitted - Highlights: • The structure of the Ca{sub 3}Ln{sub 2}Ge{sub 3}O{sub 12} (Ln=Pr, Nd, Sm, Gd and Dy) was determined. • Different distribution of Ln{sup 3+} ions on the three available crystal sites was observed. • A detailed structural study focused on the metal coordination polyhedra was performed. • The instability of the silico-carnotite structure out of the range Pr–Dy was discussed. • The luminescence of the dopant Eu{sup 3+} ion in Ca{sub 3}Gd{sub 2}Ge{sub 3}O{sub 12} was presented and analyzed.

  18. Phase diagram and magnetocaloric effects in Ni{sub 50}Mn{sub 35}(In{sub 1?x}Cr{sub x}){sub 15} and (Mn{sub 1?x}Cr{sub x})NiGe{sub 1.05} alloys

    SciTech Connect (OSTI)

    Quetz, Abdiel, E-mail: anorve2002@yahoo.com; Muchharla, Baleeswaraiah; Dubenko, Igor; Talapatra, Saikat; Ali, Naushad [Southern Illinois University, Carbondale, Illinois 62901 (United States); Samanta, Tapas; Stadler, Shane [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803 (United States)

    2014-05-07T23:59:59.000Z

    The magnetocaloric and thermomagnetic properties of Ni{sub 50}Mn{sub 35}(In{sub 1?x}Cr{sub x}){sub 15} and (Mn{sub 1?x}Cr{sub x}) NiGe{sub 1.05} systems for 0???x???0.105 and 0???x???0.1, respectively, have been studied by x-ray diffraction, differential scanning calorimetry, and magnetization measurements. Partial substitution of Cr for Mn in (Mn{sub 1?x}Cr{sub x})NiGe{sub 1.05} results in a first order magnetostructural transition from a hexagonal paramagnetic to an orthorhombic paramagnetic phase near T{sub M}???380?K (for x?=?0.07). Partial substitution of Cr for In in Ni{sub 50}Mn{sub 35}(In{sub 1?x}Cr{sub x}){sub 15} shifts the magnetostructural transition to a higher temperature (T?=?T{sub M}???450?K) for x?=?0.1. Large magnetic entropy changes of ?S?=??12 (J/(kgK)) and ?S?=??11 (J/(kgK)), both for a magnetic field change of 5?T, were observed in the vicinity of T{sub M} for (Mn{sub 1?x}Cr{sub x})NiGe{sub 1.05} and Ni{sub 50}Mn{sub 35}(In{sub 1?x}Cr{sub x}){sub 15}, respectively.

  19. Measurement of ?<sub>cj> decaying into pn??? and pn?????

    SciTech Connect (OSTI)

    Ablikim, M.; Achasov, M. N.; Albayrak, O.; Ambrose, D. J.; An, F. F.; An, Q.; Bai, J. Z.; Ban, Y.; Becker, J.; Bennett, J. V.; Bertani, M.; Bian, J. M.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; Ding, W. M.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fang, J.; Fang, S. S.; Fava, L.; Feldbauer, F.; Feng, C. Q.; Ferroli, R. B.; Fu, C. D.; Fu, J. L.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y. P.; Han, Y. L.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, H. M.; Hu, T.; Huang, G. M.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Kuehn, W.; Lai, W.; Lange, J. S.; Li, C. H.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, K.; Li, Lei; Li, Q. J.; Li, S. L.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Liao, X. T.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, C. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H.; Liu, H. H.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K. Y.; Liu, Kai; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X. Y.; Ma, Y.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Morales Morales, C.; Motzko, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nicholson, C.; Nikolaev, I. B.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Park, J. W.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Prencipe, E.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, X. S.; Qin, Y.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schaefer, B. D.; Schulze, J.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Toth, D.; Ullrich, M.; Varner, G. S.; Wang, B.; Wang, B. Q.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q.; Wang, Q. J.; Wang, S. G.; Wang, X. L.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, Q. G.; Wen, S. P.; Werner, M.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, S. X.; Wu, W.; Wu, Z.; Xia, L. G.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, G. M.; Xu, H.; Xu, Q. J.; Xu, X. P.; Xu, Z. R.; Xue, F.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, H. W.; Yu, J. S.; Yu, S. P.; Yuan, C. Z.; Yuan, Y.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, S. H.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. S.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, J. W.; Zhao, K. X.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. Z.; Zhao, S. J.; Zhao, T. C.; Zhao, X. H.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zhong, B.; Zhong, J.; Zhong, Z.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. M.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.

    2012-09-01T23:59:59.000Z

    Using a data sample of 1.06×10? ?' events collected with the BESIII detector in 2009, the branching fractions of ?<sub>cJ>?pn??? and ?<sub>cJ>?pn????? (J=0, 1, 2) are measured. (Throughout the text, inclusion of charge conjugate modes is implied if not stated otherwise.) The results for ?<sub>c?>?pn??? and ?<sub>c²>?pn??? are consistent with, but much more precise than, those of previous measurements. The decays of ?<sub>c1sub>?pn??? and ?<sub>cJ>?pn????? are observed for the first time.

  20. New ternary phosphides and arsenides. Syntheses, crystal structures, physical properties of Eu{sub 2}ZnP{sub 2}, Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}

    SciTech Connect (OSTI)

    Wang, Jian [State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Xia, Sheng-Qing, E-mail: shqxia@sdu.edu.cn [State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Tao, Xu-Tang [State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Schäfer, Marion C. [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States); Bobev, Svilen, E-mail: bobev@udel.edu [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States)

    2013-09-15T23:59:59.000Z

    Three new europium pnictides Eu{sub 2}ZnP{sub 2}, Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3} have been synthesized and their structures were determined by single-crystal X-ray diffraction. Eu{sub 2}ZnP{sub 2} is isotypic with Yb{sub 2}CdSb{sub 2} (Cmc2{sub 1} (No. 36); cell parameters a=4.1777(7) Å, b=15.925(3) Å, c=7.3008(12) Å), while the latter two compounds crystallize with the Ba{sub 2}Cd{sub 2}Sb{sub 3} structure type (C2/m (No. 12); cell parameters a=15.653(5)/16.402(1) Å, b=4.127(1)/4.445(4) Å, c=11.552(4)/12.311(1) Å and ?=126.647(4)/126.515(7)° for Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}, respectively). Magnetic susceptibility measurements in the interval 5–300 K confirm paramagnetic behavior and effective magnetic moments characteristic of Eu{sup 2+} ([Xe] 4f{sup 7}) ground states. Temperature-dependent electrical conductivity measurements also prove that Eu{sub 2}Cd{sub 2}As{sub 3} is a semiconducting compound with a narrow band gap of 0.059 eV below 100 K. According to TG/DSC analyses, Eu{sub 2}Cd{sub 2}As{sub 3} starts to decompose at about 950 K. - Graphical abstract: A polyhedral view of the crystal structure of new pnictides Eu{sub 2}T{sub 2}Pn{sub 3} (T=Zn or Cd; Pn=P or As). Display Omitted - Highlights: • Three new ternary pnictide Zintl compounds, Eu{sub 2}ZnP{sub 2}, Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}, have been synthesized and characterized. • The europium cations are divalent and ferromagnetically coupled in both Eu{sub 2}Zn{sub 2}P{sub 3} and Eu{sub 2}Cd{sub 2}As{sub 3}. • Eu{sub 2}Cd{sub 2}As{sub 3} has a very small band gap of 0.06 eV and starts to decompose over 950 K.

  1. Alteration of Coffinite (USiO{sub 4}) Under Reducing and Oxidizing Conditions

    SciTech Connect (OSTI)

    Deditius, Artur Piotr; Utsunomiya, Satoshi; Ewing, Rodney C. [Geological Sciences, University of Michigan, 1100 N. University Ave., Ann Arbor, MI, 48109 (United States)

    2007-07-01T23:59:59.000Z

    Samples of natural coffinite (USiO{sub 4}.nH{sub 2}O) from Grants uranium region, New Mexico were investigated in order to understand the alteration process of coffinite under reducing and oxidizing conditions. Alteration of the primary coffinite under reducing conditions was promoted by organic acids, and as a result, secondary coffinite precipitated. Subsequently oxidizing fluids altered the coffinite, and (Na,K)-boltwoodite [(Na,K)(UO{sub 2})(SiO{sub 3}OH)(H{sub 2}O){sub 1.5}] and jachymovite [(UO{sub 2})(SO{sub 4})(OH){sub 14}(H{sub 2}O){sub 13}] precipitated with no rare earth elements. Based on the charge balance calculation, we suggest that the amount of U{sup 6+} in the coffinite is less than 0.2 [apfu] and U{sup 6+} is accommodated in the structure via substitution: U{sup 4+} + Si{sup 4+} {r_reversible} U{sup 6+} + 2(OH){sup -}. The high and variable totals for electron microprobe analyses indicate that H{sub 2}O is not an essential component in coffinite structure. The U-Pb ages of coffinite formation vary from 36.6-0 Ma suggesting that the coffinite has precipitated continuously in this period and organic matter can preserve reducing conditions even when oxidizing conditions dominate. (authors)

  2. UF{sub 6} pressure excursions during cylinder heating

    SciTech Connect (OSTI)

    Brown, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

    1991-12-31T23:59:59.000Z

    As liquid UF{sub 6} inside a cylinder changes from a liquid to a solid, it forms a porous solid which occupies approximately the same volume as that of the liquid before cooling. Simultaneously as the liquid cools, UF{sub 6} vapor in the cylinder ullage above the liquid desublimes on the upper region of the inner cylinder wall. This solid is a dense, glass-like material which can accumulate to a significant thickness. The thickness of the solid coating on the upper cylinder wall and directly behind the cylinder valve area will vary depending on the conditions during the cooling stage. The amount of time lapsed between UF{sub 6} solidification and UF{sub 6} liquefaction can also affect the UF{sub 6} coating. This is due to the daily ambient heat cycle causing the coating to sublime from the cylinder wall to cooler areas, thus decreasing the thickness. Structural weakening of the dense UF{sub 6} layer also occurs due to cylinder transport vibration and thermal expansion. During cylinder heating, the UF{sub 6} nearest the cylinder wall will liquefy first. As the solid coating behind the cylinder valve begins to liquefy, it results in increased pressure depending upon the available volume for expansion. At the Paducah Gaseous Diffusion Plant (PGDP) during the liquefaction of the UF{sub 6} in cylinders in the UF{sub 6} feed and sampling autoclaves, this pressure increase has resulted in the activation of the systems rupture discs which are rated at 100 pounds per square inch differential.

  3. A Regional Approach to Market Monitoring in the West

    E-Print Network [OSTI]

    Barmack, Matthew; Kahn, Edward; Tierney, Susan; Goldman, Charles

    2006-01-01T23:59:59.000Z

    RTO SMUD SCED SCUC SSG-WI WAPA WECC Arizona Public Serviceaggregated form. For example, WECC publishes a daily reportfor three sub-regions of WECC, but the report does not

  4. Fluorination mechanisms of Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} surfaces irradiated by high-density CF{sub 4}/O{sub 2} and SF{sub 6}/O{sub 2} plasmas

    SciTech Connect (OSTI)

    Miwa, Kazuhiro; Takada, Noriharu; Sasaki, Koichi [Department of Electrical Engineering and Computer Science, Nagoya University, Nagoya, 464-8603 (Japan); Plasma Nanotechnology Research Center, Nagoya University, Nagoya 464-8603 (Japan)

    2009-07-15T23:59:59.000Z

    Fluorination of Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} surfaces was investigated by irradiating high-density, helicon-wave CF{sub 4}/O{sub 2} and SF{sub 6}/O{sub 2} plasmas. The Al{sub 2}O{sub 3} surface bombarded by high-flux positive ions of the CF{sub 4}/O{sub 2} plasma was fluorinated significantly. On contrast, Y{sub 2}O{sub 3} was less fluorinated than Al{sub 2}O{sub 3} when they were irradiated by the same CF{sub 4}/O{sub 2} plasma. The analysis of the Al{sub 2}O{sub 3} surface irradiated by the CF{sub 4}/O{sub 2} plasma suggests that the fluorination is triggered by reactions between fluorocarbon deposit and Al-O bonding with the assistance of ion bombardment. On the other hand, irradiation of the SF{sub 6}/O{sub 2} plasma induced less significant fluorination on the Al{sub 2}O{sub 3} surface. This suggests a lower reaction probability between sulfur fluoride deposit and Al-O bonding. The difference in the fluorination of the Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} surfaces induced by the irradiations of the CF{sub 4}/O{sub 2} and SF{sub 6}/O{sub 2} plasmas is understood by comparing the bonding energies of C-O, S-O, Al-O, and Y-O.

  5. Photosensitivity of pulsed laser deposited Ge{sub 20}As{sub 20}Se{sub 60} and Ge{sub 10}As{sub 30}Se{sub 60} amorphous thin films

    SciTech Connect (OSTI)

    Hawlová, P.; Olivier, M.; Verger, F. [Department of Graphic Arts and Photophysics, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 53210 Pardubice (Czech Republic); Nazabal, V. [Chemical Sciences Institute of Rennes (ISCR), Glasses and Ceramics Team, UMR-CNRS 6226, University of Rennes 1, 35042 Rennes Cedex (France); Department of Graphic Arts and Photophysics, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 53210 Pardubice (Czech Republic); N?mec, P., E-mail: petr.nemec@upce.cz [Department of Graphic Arts and Photophysics, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 53210 Pardubice (Czech Republic)

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • Amorphous Ge{sub 20}As{sub 20}Se{sub 60}/Ge{sub 10}As{sub 30}Se{sub 60} films are fabricated by pulsed laser deposition. • Photosensitivity of the layers is studied by employing spectroscopic ellipsometry. • As-deposited/relaxed thin films were irradiated by 593, 635, and 660 nm lasers. • Ge{sub 20}As{sub 20}Se{sub 60} layers present almost zero photorefraction in relaxed state. - Abstract: Amorphous Ge{sub 20}As{sub 20}Se{sub 60} and Ge{sub 10}As{sub 30}Se{sub 60} thin films are fabricated by pulsed laser deposition. Prepared films are characterized in terms of their morphology, chemical composition, and optical properties. Special attention is given to the photosensitivity of the layers, which was studied by spectroscopic ellipsometry with as-deposited, annealed and exposed films by three different laser sources (593, 635, and 660 nm). The results show better photostability for Ge{sub 20}As{sub 20}Se{sub 60} thin films, where photoinduced change of optical band gap was found to be equal or less than 0.04 eV and these layers present almost zero photorefraction.

  6. Dy-V magnetic interaction and local structure bias on the complex spin and orbital ordering in Dy<sub>1?xsub>TbxVO>3sub> (x=0 and 0.2)

    SciTech Connect (OSTI)

    Yan, J.-Q.; Cao, H. B.; McGuire, M. A.; Ren, Y.; Sales, B. C.; Mandrus, D. G.

    2013-06-01T23:59:59.000Z

    The spin and orbital ordering in Dy<sub>1?xsub>TbxVO>3sub> (x=0 and 0.2) was studied by measuring x-ray powder diffraction, magnetization, specific heat, and neutron single-crystal diffraction. The results show that G-OO/C-AF and C-OO/G-AF phases coexist in Dy<sub>0.8sub>Tb>0.20sub>VO>3sub> in the temperature range 2–60 K, and the volume fraction of each phase is temperature and field dependent. The ordering of Dy moments at T*?=?12 K induces a transition from G-OO/C-AF to a C-OO/G-AF phase. Magnetic fields suppress the long-range order of Dy moments and thus the C-OO/G-AF phase below T*. The polarized moments induced at the Dy sublattice by external magnetic fields couple to the V 3d moments, and this coupling favors the G-OO/C-AF state. Also discussed is the effect of the Dy-V magnetic interaction and local structure distortion on the spin and orbital ordering in Dy<sub>1?xsub>TbxVO>3sub>.

  7. A novel organic–inorganic hybrid with Anderson type polyanions as building blocks: (C{sub 6}H{sub 10}N{sub 3}O{sub 2}){sub 2}Na(H{sub 2}O){sub 2}[Al(OH){sub 6}Mo{sub 6}O{sub 18}]·6H{sub 2}O

    SciTech Connect (OSTI)

    Thabet, Safa, E-mail: safathabet@hotmail.fr [Laboratoire de matériaux et cristallochimie, Département de chimie, Institut Supérieur des Sciences Appliquées et Technologier, Avenue El Mourouj, 5111 Mahdia (Tunisia)] [Laboratoire de matériaux et cristallochimie, Département de chimie, Institut Supérieur des Sciences Appliquées et Technologier, Avenue El Mourouj, 5111 Mahdia (Tunisia); Ayed, Brahim, E-mail: brahimayed@yahoo.fr [Laboratoire de matériaux et cristallochimie, Département de chimie, Institut Supérieur des Sciences Appliquées et Technologier, Avenue El Mourouj, 5111 Mahdia (Tunisia)] [Laboratoire de matériaux et cristallochimie, Département de chimie, Institut Supérieur des Sciences Appliquées et Technologier, Avenue El Mourouj, 5111 Mahdia (Tunisia); Haddad, Amor [Laboratoire de matériaux et cristallochimie, Département de chimie, Institut Supérieur des Sciences Appliquées et Technologier, Avenue El Mourouj, 5111 Mahdia (Tunisia)] [Laboratoire de matériaux et cristallochimie, Département de chimie, Institut Supérieur des Sciences Appliquées et Technologier, Avenue El Mourouj, 5111 Mahdia (Tunisia)

    2012-11-15T23:59:59.000Z

    Graphical abstract: Display Omitted Highlights: ? Synthesis of a novel inorganic–organic hybrid compound based on Anderson polyoxomolybdates. ? Characterization by X-ray diffraction, IR and UV–Vis spectroscopies of the new compound. ? Potential applications in catalysis, biochemical analysis and electrical conductivity of the organic–inorganic compound. -- Abstract: A new organic–inorganic hybrid compound based on Anderson polyoxomolybdates, (C{sub 6}H{sub 10}N{sub 3}O{sub 2}){sub 2}Na(H{sub 2}O){sub 2}[Al(OH){sub 6}Mo{sub 6}O{sub 18}]·6H{sub 2}O (1) have been isolated by the conventional solution method and characterized by single-crystal X-ray diffraction, infrared, ultraviolet spectroscopy and Thermogravimetric Analysis (TGA). This compound crystallized in the triclinic system, space group P?1, with a = 94.635(1) ?, b = 10.958(1) ?, c = 11.602(1) ?, ? = 67.525(1)°, ? = 71.049(1)°, ? = 70.124(1)° and Z = 1. The crystal structures of the compounds exhibit three-dimensional supramolecular assembly based on the extensive hydrogen bonding interactions between organic cations, sodium cations, water molecules and Anderson polyoxoanions. The infrared spectrum fully confirms the X-ray crystal structure and the UV spectrum of the title compound exhibits an absorption peak at 210 nm.

  8. High thermal stability of piezoelectric properties in (Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}){sub x}-(BaTiO{sub 3}){sub y}-(Na{sub 0.5}K{sub 0.5}NbO{sub 3}){sub 1-x-y} ceramics

    SciTech Connect (OSTI)

    Gupta, Shashaank; Priya, Shashank [Bio-Inspired Materials and Devices Laboratory (BMDL), Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Bio-Inspired Materials and Devices Laboratory (BMDL), Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2013-01-07T23:59:59.000Z

    We report the piezoelectric and ferroelectric properties of (Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}){sub x}-(BaTiO{sub 3}){sub y}-(Na{sub 0.5}K{sub 0.5}NbO{sub 3}){sub 1-x-y} ceramics for Na{sub 0.5}K{sub 0.5}NbO{sub 3} rich end of composition (x, y {<=} 0.04 mol. %). These compositions were found to exhibit significantly improved thermal stability of piezoresponse. Variation of dielectric constant as a function of temperature revealed that orthorhombic-tetragonal (T{sub o-t}) and tetragonal-cubic (T{sub c}) transition temperatures for these compositions were in the vicinity of 0 Degree-Sign C and 330 Degree-Sign C, respectively. Dynamic scaling and temperature dependent X-ray diffraction analysis were conducted. Results are discussed in terms of intrinsic and extrinsic contributions to the piezoelectric response explaining the temperature dependent behavior.

  9. Production of S/sub 2/F/sub 10/ by SF/sub 6/ spark discharges

    SciTech Connect (OSTI)

    Sauers, I.; Votaw, P.C.; Griffin, G.D.

    1988-01-01T23:59:59.000Z

    The highly toxic compound S/sub 2/F/sub 10/ is formed in SF/sub 6/ following spark discharges. When the spark cell is dried, the S/sub 2/F/sub 10/ yield was 6.8 /times/ 10/sup /minus/11/ mol/J at an SF/sub 6/ pressure P = 133 kPa. Moisture appears to suppress the S/sub 2/F/sub 10/ yield, although once formed, the S/sub 2/F/sub 10/ is quite stable with respect to moisture. This could explain the variation in observation from experiment to experiment in the literature. These results also raise important questions as to the influence of drying agents that are used in high-voltage systems on the S/sub 2/F/sub 10/ yield. 13 refs., 2 figs., 1 tab.

  10. Structural, optical and dielectric property of Co doped Bi{sub 2}Fe{sub 4}O{sub 9}

    SciTech Connect (OSTI)

    Swain, Smita, E-mail: singhanil@nitrkl.ac.in; Mohapatra, S. R., E-mail: singhanil@nitrkl.ac.in; Sahoo, B., E-mail: singhanil@nitrkl.ac.in; Singh, A. K., E-mail: singhanil@nitrkl.ac.in [Department of Physics, National Institute of Technology, Rourkela -769008, Odisha (India)

    2014-04-24T23:59:59.000Z

    Multiferroic Bi{sub 2}Fe{sub 4}O{sub 9} and Co doped Bi{sub 2}Fe{sub 4}O{sub 9} are prepared by solid state route reaction method using bismuth oxide(Bi{sub 2}O{sub 3}), iron oxide(Fe{sub 2}O{sub 3}) and cobalt oxide (Co{sub 3}O{sub 4}). Their structural optical and dielectric properties are studied and compared. X-ray diffraction (XRD) results confirm that there is no change in crystal structure due to Co doping. From dielectric constant measurement we conclude that dielectric constant increases due to Co doping. UV-Visible plot shows due to Co doping bang gap energy increases.

  11. Millimeter size single crystals of superconducting YBa[sub 2]Cu[sub 3]O[sub x

    DOE Patents [OSTI]

    Damento, M.A.; Gschneidner, K.A. Jr.

    1989-04-25T23:59:59.000Z

    A method of growing large, up to 1 mm size single crystals of superconducting YBa[sub 2]Cu[sub 3]O[sub x], wherein x equals from 6.5 to 7.2 is disclosed.

  12. Interaction of Ce{sub 1?x}Er{sub x}O{sub 2?y} nanoparticles with SiO{sub 2}-effect of temperature and atmosphere

    SciTech Connect (OSTI)

    Kepinski, L., E-mail: L.Kepinski@int.pan.wroc.pl; Krajczyk, L.; Mista, W.

    2014-01-15T23:59:59.000Z

    Morphology, microstructure and phase evolution of homogeneous, nanocrystalline Ce{sub 1?x}Er{sub x}O{sub 2?x/2} mixed oxide (x=0.3 and 0.5), prepared by microemulsion method, supported on amorphous SiO{sub 2} was studied in oxidizing and reducing atmosphere by XRD, TEM, SEM-EDS and N{sub 2} adsorption. The system is structurally and chemically stable in the oxidizing atmosphere up to 1000 °C, exhibiting only a small increase of the mean crystallite size of the oxide to ?4 nm. At 1100 °C formation of Er silicate with unusual structure isomorphic with y-Y{sub 2}Si{sub 2}O{sub 7} (yttrialite), stabilized by Ce{sup 4+} ions was observed. In the reducing atmosphere the Ce{sub 1?x}Er{sub x}O{sub 2?x/2} reacted with SiO{sub 2} already at 900 °C, due to high affinity of the reduced Ce{sup 3+} to form a silicate phase. At higher temperature the silicate crystallized into the tetragonal, low temperature A-(Ce{sub 1?x}Er{sub x}){sub 2}Si{sub 2}O{sub 7} polymorph. Such systems, containing nanocrystalline silicate particles with Er{sup 3+} ions placed in well defined sites embedded in silica matrix, may be interesting as highly efficient active components of optical waveguides amplifiers integrated with Si microelectronics. The nanocrystalline Ce–Er–O/SiO{sub 2} system prepared by the impregnation of the silica with the aqueous solution of nitrates appeared to be chemically inhomogeneous and less stable in both oxidising and reducing atmosphere. - Graphical abstract: Structure evolution of Ce{sub 0.5}Er{sub 0.5}O{sub 1.75} in air and in H{sub 2}. Display Omitted - Highlights: • Homogeneous 3 nm Ce{sub 1?x}Er{sub x}O{sub 2?y} particles were prepared and uniformly dispersed on SiO{sub 2}. • Er diffusion to SiO{sub 2} determines the stability of the mixed oxide in air to ?1000 °C. • Spreading of Ce{sub 1?x}Er{sub x}O{sub 2?y} onto SiO{sub 2} occurs in hydrogen at 900 °C. • Nanocrystalline A-(Ce,Er){sub 2}Si{sub 2}O{sub 7} silicate forms in H{sub 2} at 1100 °C.

  13. Synthesis, crystal structure and magnetic properties of Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}

    SciTech Connect (OSTI)

    Kokal, I. [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey); Aydemir, U., E-mail: uaydemir@ku.edu.tr [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey); Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str.40, Dresden 01187 (Germany); Prots, Yu.; Förster, T.; Sichelschmidt, J. [Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str.40, Dresden 01187 (Germany); Yahyaoglu, M. [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey); Auffermann, G.; Schnelle, W. [Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str.40, Dresden 01187 (Germany); Schappacher, F.; Pöttgen, R. [Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstraße 30, Münster 48149 (Germany); Somer, M., E-mail: msomer@ku.edu.tr [Koç University, Rumelifeneri Yolu, Sariyer, Istanbul 34450 (Turkey)

    2014-02-15T23:59:59.000Z

    Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] was synthesized from the metathesis reaction of Li{sub 3}[BN{sub 2}] and EuCl{sub 3} at 850 °C. Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] crystallizes in the trigonal space group R3{sup ¯}c (No. 167) with a=12.0225(2) Å, c=6.8556(2) Å and Z=6. In the crystal structure, isolated, planar cyclic [B{sub 3}N{sub 6}]{sup 9?} units are charge-balanced by the mixed-valence Eu{sup 3+}/Eu{sup 2+} and Li{sup +} cations. Li{sup +} occupies partially (44%) the Wyckoff site 6b and is sandwiched between the [B{sub 3}N{sub 6}]{sup 9?} anions. Mössbauer spectroscopy results show the resonance lines of Eu{sup 2+} and Eu{sup 3+}, respectively, indicating the heterogeneous mixed valency of the Eu atoms. X-Band ESR investigations between 5 and 300 K reveal an intense signal over the whole temperature range originating from Eu{sup 2+}. Magnetic susceptibility measurements indicate a Curie–Weiss behavior with an experimental effective magnetic moment of ?{sub eff}=8.28 ?{sub B} per formula unit. - Graphical abstract: Single crystals of Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] was obtained from the metathesis reaction of Li{sub 3}[BN{sub 2}] and EuCl{sub 3.}{sup 151}Eu Mössbauer, ESR and magnetic susceptibility measurements reveal the heterogeneous mixed valency of the Eu atoms. Display Omitted - Highlights: • Single crystals of Li{sub 0.44}Eu{sub 3}[B{sub 3}N{sub 6}] was obtained from the metathesis reaction of Li{sub 3}[BN{sub 2}] and EuCl{sub 3} at 850 °C. • Crystal structure is built up by isolated, planar cyclic [B{sub 3}N{sub 6}]{sup 9?} units which are surrounded by mixed valence Eu{sup 3+}/Eu{sup 2+}. • Li{sup +} occupies partially (44%) the site 6b and is sandwiched between the [B{sub 3}N{sub 6}]{sup 9?} anions. • The {sup 151}Eu Mössbauer spectroscopy, electron spin resonance spectroscopy and magnetic susceptibility measurements confirm the heterogeneous mixed valency of Eu.

  14. Prepared Statement for Mr. Michael P. Mertz Director, NERC Regulatory...

    Broader source: Energy.gov (indexed) [DOE]

    cyber security training, with many receiving role based training such as the Control Systems Security training programs offered through the Department of Energy National SCADA...

  15. NERC Presentation: Accommodating High Levels of Variable Generation...

    Office of Environmental Management (EM)

    of variable electricity eneration. Variable resources are types of electric power generation that rely on an uncontrolled, "variable" fuel (e.g. wind, sunlight, waves, tidal...

  16. Transmission Vegetation Management NERC Standard FAC-003-2 Technical...

    Open Energy Info (EERE)

    background to the requirements of the Standard. The intentions of the Standard Drafting Team in developing many key areas of this Revision are also explained in this document. The...

  17. NERC Peer Review College Members January 2014 1

    E-Print Network [OSTI]

    Brierley, Andrew

    Allessandro Battaglia University of Leicester http://www2.meteo.uni-bonn.de/mitarbeiter/battaglia/ Mr Martin

  18. Comments of North American Electric Reliability Corporation (NERC) to DOE

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613PortsmouthBartlesville EnergyDepartment. CashDay-June 22, 2015

  19. Property:EIA/861/NercErcot | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,PillarPublicationType JumpDOEInvolve JumpallowedAltFuelVehicle JumpIsoNy

  20. Property:EIA/861/NercNpcc | Open Energy Information

    Open Energy Info (EERE)

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  1. Comments of North American Electric Reliability Corporation (NERC) to DOE

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: Theof"Wave the WhiteNational Broadband Plan byCommentsComments ofSmart Grid

  2. Microsoft PowerPoint - SWL NERC status june 2009.ppt

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand RetrievalsFinalModule8.pptStatesEnergyAnStateProjectsof09

  3. Property:EIA/861/NercMro | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid Jump to: navigation,AltFuelVehicle2 Jump

  4. Sandia Energy - North American Electric Reliability Corporation (NERC)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiationImplementing Nonlinear757Kelley RuehlReport Posted North American Electric

  5. NERC Presentation: Accommodating High Levels of Variable Generation,

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33Frequently Asked QuestionsDepartment of Energy 3ServicesNEET FY 12a-12Environmental Policy

  6. Transmission Vegetation Management NERC Standard FAC-003-2 Technical

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown of Ladoga, Indiana (Utility Company) JumpTradeWindPrepared as Information

  7. NERC IVGTF Task 1-3 Section 3-1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your1 SECTIONES2008-54174MoreMuseum|NEESReading Room |98

  8. Transport and magnetism in La{sub 2/3}Ca{sub 1/3}(Mn{sub 1{minus}x}Co{sub x})O{sub 3} and La{sub 2/3}Ca{sub 1/3}(Mn{sub 1{minus}x}Ni{sub x})O{sub 3} (abstract)

    SciTech Connect (OSTI)

    Rubinstein, M.; Tritt, T.M.; Synder, J.E. [U.S. Naval Research Laboratory, Washington, D.C. 20375 (United States)] [U.S. Naval Research Laboratory, Washington, D.C. 20375 (United States)

    1997-04-01T23:59:59.000Z

    La{sub 2/3}Ca{sub 1/3}MnO{sub 3} is a strong double-exchange ferromagnet where the ratio of La{sup 3+}{endash}Ca{sup 2+} ions has been chosen to maximize its favorable magnetic and transport properties. The Mn ion is unique as an effective participant in the double-exchange process. It is of interest to add Ni or Co atoms substitutionally for Mn in the form of La{sub 2/3}Ca{sub 1/3}(Mn{sub 1{minus}x}Co{sub x})O{sub 3} and La{sub 2/3}Ca{sub 1/3}(Mn{sub 1{minus}x}Ni{sub x})O{sub 3} in order to determine the relative importance of the double-exchange interaction as the Mn concentration is reduced. Powder x-ray diffraction reveals we can retain the original orthorhombic structure of La{sub 2/3}Ca{sub 1/3}MnO{sub 3} (with up to 50{percent} Co or Ni substitution) by a series of anneals at 1300{degree}C followed by repeated grindings. We have investigated the magnetization, electrical conductivity, and thermopower of these mixed transition-metal perovskites. For La{sub 2/3}Ca{sub 1/3}(Mn{sub 1{minus}x}Co{sub x})O{sub 3}, the magnetization decreases with added Co, but ferromagnetism is retained (at least up to 50{percent} Co). Although metallic conductivity is still present at 10{percent} Co concentration, these Co{endash}Mn perovskites become insulating for x{ge}0.2. For La{sub 2/3}Ca{sub 1/3}(Mn{sub 1{minus}x}Ni{sub x})O{sub 3}, the metallic state is retained at least until x=0.5. The magnetic properties exhibit spin-glasslike behavior for x{ge}0.25. {copyright} {ital 1997 American Institute of Physics.}

  9. Nanostructured Ge{sub 2}Sb{sub 2}Te{sub 5} chalcogenide films produced by laser electrodispersion

    SciTech Connect (OSTI)

    Yavsin, D. A., E-mail: yavsin@mail.ioffe.ru; Kozhevin, V. M.; Gurevich, S. A.; Yakovlev, S. A.; Melekh, B. T.; Yagovkina, M. A.; Pevtsov, A. B. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2014-12-15T23:59:59.000Z

    Amorphous nanostructured films of a complex chalcogenide (Ge{sub 2}Sb{sub 2}Te{sub 5}) are produced by laser electrodispersion and their structural and electrical properties are studied. It is found that the characteristic size of Ge{sub 2}Sb{sub 2}Te{sub 5} nanoparticles in the structure of the films is 1.5–5 nm.

  10. Quadruple-layered perovskite (CuCl)Ca{sub 2}NaNb{sub 4}O{sub 13}

    SciTech Connect (OSTI)

    Kitada, A.; Tsujimoto, Y.; Yamamoto, T. [Department of Energy and Hydrocarbon Chemistry, Faculty of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510 (Japan); Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Kobayashi, Y. [Department of Energy and Hydrocarbon Chemistry, Faculty of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510 (Japan); Narumi, Y. [Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 (Japan); Institute for Materials Research, Tohoku University, Katahira 2-1-1, Sendai 980-8577 (Japan); Kindo, K. [Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 (Japan); Aczel, A.A.; Luke, G.M. [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1 (Canada); Uemura, Y.J. [Department of Physics, Columbia University, New York, NY 10027 (United States); Kiuchi, Y.; Ueda, Y. [Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 (Japan); Yoshimura, K. [Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Ajiro, Y. [Department of Energy and Hydrocarbon Chemistry, Faculty of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510 (Japan); Kageyama, H., E-mail: kage@scl.kyoto-u.ac.jp [Department of Energy and Hydrocarbon Chemistry, Faculty of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510 (Japan); Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Institute for Integrated Cell-Material Sciences, Kyoto University, Sakyo, Kyoto 606-8501 (Japan); CREST, Japan Science and Technology Agency, Kawaguchi 332-0012 (Japan)

    2012-01-15T23:59:59.000Z

    We will present the synthesis, structure and magnetic properties of a new quadruple-layered perovskite (CuCl)Ca{sub 2}NaNb{sub 4}O{sub 13}. Through a topotactic ion-exchange reaction with CuCl{sub 2}, the precursor RbCa{sub 2}NaNb{sub 4}O{sub 13} presumably having an incoherent octahederal tliting changes into (CuCl)Ca{sub 2}NaNb{sub 4}O{sub 13} with a 2a{sub p} Multiplication-Sign 2a{sub p} Multiplication-Sign 2c{sub p} superstructure (tetragonal; a=7.73232(5) A, c=39.2156(4) A). The well-defined superstructure for the ion-exchanged product should be stabilized by the inserted CuCl{sub 4}O{sub 2} octahedral layers that firmly connect with neighboring perovskite layers. Magnetic studies show the absence of long-range magnetic ordering down to 2 K despite strong in-plane interactions. Aleksandrov Prime s group theory and Rietveld refinement of synchrotron X-ray diffraction data suggest the structure to be of I4/mmm space group with in-phase tilting along the a and b axes, a two-tilt system (++0). - Graphical Abstract: We present a quadruple-layered copper oxyhalide (CuCl)Ca{sub 2}NaNb{sub 4}O{sub 13} synthesized through a topotactic ion-exchange reaction of RbCa{sub 2}NaNb{sub 4}O{sub 13} with CuCl{sub 2}. The compound has a well-defined superstructure. Magnetic studies suggest the absence of magnetic order even at 2 K. Highlights: Black-Right-Pointing-Pointer (CuCl)Ca{sub 2}NaNb{sub 4}O{sub 13} was prepared by ion-exchange reaction of RbCa{sub 2}NaNb{sub 4}O{sub 13} with CuCl{sub 2}. Black-Right-Pointing-Pointer Compound has a 2a{sub p} Multiplication-Sign 2a{sub p} Multiplication-Sign 2c{sub p} superstructure (tetragonal; a=7.73 A, c=39.21 A). Black-Right-Pointing-Pointer Such a well-defined superstructure was not observed in the precursor compound. Black-Right-Pointing-Pointer Aleksandrov Prime s theory and Rietveld study suggest a (++0) octahedral tilting (I4/mmm). Black-Right-Pointing-Pointer Magnetic studies revealed the absence of magnetic order down to 2 K.

  11. Method for preparation of textured YBa.sub.2 Cu.sub.3 O.sub.x superconductor

    DOE Patents [OSTI]

    Selvamanickam, Venkat (Guilderland, NY); Goyal, Amit (Knoxville, TN); Kroeger, Donald M. (Knoxville, TN)

    1998-01-01T23:59:59.000Z

    The present invention relate to textured YBa.sub.2 Cu.sub.3 O.sub.x (Y-123) superconductors and a process of preparing them by directional recrystallization of compacts fabricated from quenched YBCO powders at temperatures about 100.degree. C. below the peritectic temperature to provide a superconductor where more than 75% of the YBa.sub.2 Cu.sub.3 O.sub.x phase is obtained without any Y.sub.2 BaCuO.sub.5 .

  12. Magnetovolume effect in Ho{sub 2}Fe{sub 17-x}Mn{sub x} compounds

    SciTech Connect (OSTI)

    Wang, J. L. [Institute for Superconductivity and Electronic Materials, University of Wollongong (Australia); Bragg Institute, ANSTO, Menai, NSW 2234 (Australia); School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Canberra, ACT 2600 (Australia); Studer, A. J.; Kennedy, S. J. [Bragg Institute, ANSTO, Menai, NSW 2234 (Australia); Zeng, R.; Dou, S. X. [Institute for Superconductivity and Electronic Materials, University of Wollongong (Australia); Campbell, S. J. [School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Canberra, ACT 2600 (Australia)

    2012-04-01T23:59:59.000Z

    The structural and magnetic properties of seven compounds in the Ho{sub 2}Fe{sub 17-x}Mn{sub x} series (x = 0-5) have been investigated. The spontaneous magnetization M{sub s} at 10 K exhibits a minimum at x{approx_equal} 3.8 while the 3d-sublattice magnetization M{sub T} is found to decrease at {approx} -3.4 {mu}{sub B}/per Mn atom compared with the rate of {approx}-2.0 {mu}{sub B}/per Mn atom expected from a simple dilution model. All of the Ho{sub 2}Fe{sub 17-x}Mn{sub x} compounds exhibit anisotropic thermal expansion below their Curie temperatures leading to the presence of strong magnetovolume effects and Invar-type behavior below T{sub C}. An approximately zero volume thermal expansion has been detected between 10 K and 270 K for Ho{sub 2}Fe{sub 17}. The maximum magnetic entropy changes for Ho{sub 2}Fe{sub 17-x}Mn{sub x} with x = 0 and 2.0 are 3.2 J kg{sup -1} K{sup -1} around T{sub C} {approx} 336 K and 2.7 J kg{sup -1} K{sup -1} around T{sub C} {approx} 302 K, respectively, for magnetic field change of B = 0-5 T.

  13. Mechanochemical-thermal preparation and structural studies of mullite-type Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} solid solutions

    SciTech Connect (OSTI)

    Da Silva, K.L. [Institute of Physical and Theoretical Chemistry, Technische Universitaet Braunschweig, Hans-Sommer-Str. 10, 38106 Braunschweig (Germany); Institute of Physical Chemistry and Electrochemistry, Leibniz University Hannover, Callinstr. 3a, 30167 Hannover (Germany); Department of Physics, State University of Maringa, Av. Colombo 5790, 87020-900 Maringa (Brazil); Sepelak, V., E-mail: vladimir.sepelak@kit.ed [Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Duevel, A. [Institute of Physical Chemistry and Electrochemistry, Leibniz University Hannover, Callinstr. 3a, 30167 Hannover (Germany); Paesano, A. [Department of Physics, State University of Maringa, Av. Colombo 5790, 87020-900 Maringa (Brazil); Hahn, H. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Litterst, F.J. [Institute of Condensed Matter Physics, Technische Universitaet Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig (Germany); Heitjans, P. [Institute of Physical Chemistry and Electrochemistry, Leibniz University Hannover, Callinstr. 3a, 30167 Hannover (Germany); Becker, K.D. [Institute of Physical and Theoretical Chemistry, Technische Universitaet Braunschweig, Hans-Sommer-Str. 10, 38106 Braunschweig (Germany)

    2011-05-15T23:59:59.000Z

    A series of Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} solid solutions (0{<=}x{<=}1), prepared by mechanochemical processing of Bi{sub 2}O{sub 3}/Ga{sub 2}O{sub 3}/Al{sub 2}O{sub 3} mixtures and subsequent annealing, was investigated by XRD, EDX, and {sup 27}Al MAS NMR. The structure of the Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} solid solutions is found to be orthorhombic, space group Pbam (No. 55). The lattice parameters of the Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} series increase linearly with increasing gallium content. Rietveld refinement of the XRD data as well as the analysis of the {sup 27}Al MAS NMR spectra show a preference of gallium cations for the tetrahedral sites in Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9}. As a consequence, this leads to a far from random distribution of Al and Ga cations across the whole series of solid solutions. -- Graphical Abstract: Mullite-type Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} mixed crystals (0{<=}x{<=}1) prepared by a combined mechanochemical-thermal route possess a non-random distribution of Ga{sup 3+} and Al{sup 3+} cations over the sites of tetrahedral (T) and octahedral [O] coordination, characterized by the preference of Ga{sup 3+} (Al{sup 3+}) for tetrahedral (octahedral) sites. Display Omitted Highlights: {yields} Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} (0{<=}x{<=}1) were synthesized via mechanochemical-thermal route. {yields} The lattice parameters of Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} increase linearly with gallium content. {yields} Quantitative information on the cation distribution in Bi{sub 2}(Ga{sub x}Al{sub 1-x}){sub 4}O{sub 9} is derived. {yields} Ga{sup 3+} and Al{sup 3+} show the preference for tetrahedral and octahedral sites, respectively.

  14. Effect of hydrogen ratio on plasma parameters of N{sub 2}-H{sub 2} gas mixture glow discharge

    SciTech Connect (OSTI)

    El-Brulsy, R. A.; Abd Al-Halim, M. A.; Abu-Hashem, A. [Benha University, Physics Department, Faculty of Science (Egypt); Rashed, U. M. [Alazhar University, Physics Department, Faculty of Science (Egypt); Hassouba, M. A. [Benha University, Physics Department, Faculty of Science (Egypt)

    2012-05-15T23:59:59.000Z

    A dc plane glow discharge in a nitrogen-hydrogen (N{sub 2}-H{sub 2}) gas mixture has been operated at discharge currents of 10 and 20 mA. The electron energy distribution function (EEDF) at different hydrogen concentrations is measured. A Maxwellian EEDF is found in the positive column region, while in both cathode fall and negative glow regions, a non-Maxwellian one is observed. Langmuir electric probes are used at different axial positions, gas pressures, and hydrogen concentrations to measure the electron temperature and plasma density. The electron temperature is found to increase with increasing H{sub 2} concentration and decrease with increasing both the axial distance from the cathode and the mixture pressure. At first, with increasing distance from the cathode, the ion density decreases, while the electron density increases; then, as the anode is further approached, they remain nearly constant. At different H{sub 2} concentrations, the electron and ion densities decrease with increasing the mixture pressure. Both the electron and ion densities slightly decrease with increasing H{sub 2} concentration.

  15. Influence of Au nanoparticles on the photoluminescent and electrical properties of Bi{sub 3.6}Eu{sub 0.4}Ti{sub 3}O{sub 12} ferroelectric thin films

    SciTech Connect (OSTI)

    Su, Li; Qin, Ni, E-mail: qinni2@mail.sysu.edu.cn, E-mail: stsbdh@mail.sysu.edu.cn; Xie, Wei; Fu, Jianhui; Bao, Dinghua, E-mail: qinni2@mail.sysu.edu.cn, E-mail: stsbdh@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275 (China)

    2014-07-21T23:59:59.000Z

    Au-doped Bi{sub 3.6}Eu{sub 0.4}Ti{sub 3}O{sub 12} (BET) thin films were prepared on fused silica and Pt/Ti/SiO{sub 2}/Si substrates by a chemical solution deposition method. The existence of Au nanoparticles (NPs) has been confirmed by X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscope analysis. Enhanced photoluminescence (PL) of Eu{sup 3+} ions was obtained in a wide range of Au doping level. Role of the Au NPs in the PL enhancement was investigated by means of optical absorption, excitation, and emission spectra, as well as decay lifetime measurements. The results indicated that the intra-4f transition of Eu{sup 3+} ions can be intensively activated by the coupling of the charge transfer band of BET with the {sup 5}D{sub 0} state of Eu{sup 3+} ions. The influence of Au NPs on the PL properties of Eu{sup 3+} ions in the present thin films was attributed to the band bending at Au/BET interface and the localized surface plasma resonance absorption of Au NPs in the visible light region. The dielectric and ferroelectric properties of Au-doped BET thin films were investigated as well.

  16. Enhanced ferromagnetic order in Sr{sub 4}Mn{sub 3}O{sub 3}(GeO{sub 4}){sub 3} featuring canted [MnO{sub 4}]{sub ?} spin chains of mixed-valent Mn(III)/Mn(IV). Aliovalent substitution of the Sr{sub 4?x}Ln{sub x}Mn{sup III}{sub 2+x}Mn{sup IV}{sub 1?x}O{sub 3}(GeO{sub 4}){sub 3} solid-solution

    SciTech Connect (OSTI)

    West, J. Palmer; Sulejmanovic, Dino [Department of Chemistry, Clemson University, Clemson, SC 29634 (United States); Becht, Gregory [E. I. du Pont, Wilmington, DE 19880-0500 (United States); He, Jian; Hitchcock, Dale [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634 (United States); Yan, Yonggao [Wuhan University of Technology, Wuhan 430070 (China); Hwu, Shiou-Jyh, E-mail: shwu@clemson.edu [Department of Chemistry, Clemson University, Clemson, SC 29634 (United States)

    2013-10-15T23:59:59.000Z

    Crystals of Sr{sub 4?x}Ln{sub x}Mn{sub 3}O{sub 3}(GeO{sub 4}){sub 3} (x=0; x?0.15 for Ln=La, Pr, Nd, Sm. Eu, Gd, Dy; x?0.3 for Ln=Gd) were isolated upon using high-temperature, solid-state methods in molten-salt media. These compounds are isostructural with the previously reported Na{sub 3}LnMn{sub 3}O{sub 3}(AsO{sub 4}){sub 3} (Ln=La, Sm, Gd) series that contains the same [MnO{sub 4}]{sub ?} spin chains. The synthesis of the Sr{sub 4}Mn{sub 3}O{sub 3}(GeO{sub 4}){sub 3} (x=0) phase was carried out by a double aliovalent substitution with respect to the Sr{sup 2+} and Ge{sup 4+} ions that replace Na{sup +}/Ln{sup 3+} and As{sup 5+} in Na{sub 3}LnMn{sub 3}O{sub 3}(AsO{sub 4}){sub 3}, respectively. The title series contains mixed-valent Mn(III)/Mn(IV) and shows a limited range of solid solution, both of which were not observed in the previously reported Na{sub 3}LnMn{sub 3}O{sub 3}(AsO{sub 4}){sub 3} series. To form the Sr{sub 4?x}Ln{sub x}Mn{sub 3}O{sub 3}(GeO{sub 4}){sub 3} solid solution, one of the Sr{sup 2+} sites, i.e., the original Ln-site in Na{sub 3}LnMn{sub 3}O{sub 3}(AsO{sub 4}){sub 3}, is partially substituted by Ln{sup 3+} in a statistical disorder of Sr{sub 1?x}/Ln{sub x}. Initial magnetic investigations of selected derivatives reveal higher ferromagnetic ordering temperatures than those reported for the Na{sub 3}LnMn{sub 3}O{sub 3}(AsO{sub 4}){sub 3} series, presumably attributed to a lesser degree of canting as a result of introducing non-Jahn–Teller Mn{sup 4+} ions. Also intriguing is the observation of multiple anomalies at low temperatures which appear to be of electronic origins. - Graphical abstract: Sr{sub 4?x}Ln{sub x}Mn(III){sub 2+x}Mn(IV){sub 1?x}O{sub 3}(GeO{sub 4}){sub 3}. Display Omitted - Highlights: • Double aliovalent substitution: Sr{sub 4}Mn{sub 3}O{sub 3}(GeO{sub 4}){sub 3} with respect to Na{sub 3}LnMn{sub 3}O{sub 3}(AsO{sub 4}){sub 3}. • Solid solution with respect to statistical disorder of Sr{sub 1?x}Ln{sub x} in one of the two Sr sites. • Mn{sup 3+}/Mn{sup 4+} magnetic ions are spatially arranged in a triangular kagomé fashion. • Enhanced ferromagnetic ordering attributed to doping non-Jahn–Teller Mn{sup 4+}.

  17. Search for B?<sub>s> ? ?+ ?- and B?<sub>d> ? mu+mu- decays in p anti-p collisions with CDF. II.

    SciTech Connect (OSTI)

    Abulencia, A.; Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; Annovi, A.; Antos, J.; Aoki, M.; Apollinari, G.; Arguin, J. -F.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Attal, A.; Azfar, F.

    2005-08-01T23:59:59.000Z

    We report on a search for B?<sub>s> ? ?+ ?- and B?<sub>d> ? mu+mu- decays in p anti-p collisions at ?s = 1.96 TeV using 364.4 pb -1 of data collected by the CDF II dectector at Fermilab Tevatron Collider. After applying all selection requirements, we observe no candidates inside the B?<sub>s> or B?<sub>d> mass windows. The resulting upper limits on the branching fractions are ?(B?<sub>s> ? ?+?-) < 1.5 x 10-7 and ?(B?<sub>d> ? ?+?-) < 3.9 x 10-8 at 90 % confidence level. (auth)

  18. Visible-light absorption and large band-gap bowing of GaN<sub>1-xsub>Sbx> from first principles

    SciTech Connect (OSTI)

    Sheetz, R. Michael; Richter, Ernst; Andriotis, Antonis N.; Lisenkov, Sergey; Pendyala, Chandrashekhar; Sunkara, Mahendra K.; Menon, Madhu

    2011-08-01T23:59:59.000Z

    Applicability of the Ga(Sb<sub>x)N>1-xsub> alloys for practical realization of photoelectrochemical water splitting is investigated using first-principles density functional theory incorporating the local density approximation and generalized gradient approximation plus the Hubbard U parameter formalism. Our calculations reveal that a relatively small concentration of Sb impurities is sufficient to achieve a significant narrowing of the band gap, enabling absorption of visible light. Theoretical results predict that Ga(Sb<sub>x)N>1-xsub> alloys with 2-eV band gaps straddle the potential window at moderate to low pH values, thus indicating that dilute Ga(Sb<sub>x)N>1-xsub> alloys could be potential candidates for splitting water under visible light irradiation.

  19. 851 S.W. Sixth Avenue, Suite 1100 Steve Crow 503-222-5161 Portland, Oregon 97204-1348 Executive Director 800-452-5161

    E-Print Network [OSTI]

    the Loss-of-Load Expectation (LOLE) work group to develop its planning standards. Unfortunately, NERC funding wasn't sufficient to sustain the work group and so, in 2012, the work group was subsumed an acceptable threshold for such a metric. Summaries, to date, show that seven of the eight NERC sub

  20. Synthetic CO.sub.2 acceptor

    DOE Patents [OSTI]

    Lancet, Michael S. (Pittsburgh, PA); Curran, George P. (Pittsburgh, PA)

    1981-08-18T23:59:59.000Z

    A synthetic CO.sub.2 acceptor consisting essentially of at least one compound selected from the group consisting of calcium oxide and calcium carbonate supported in a refractory carrier matrix, the carrier having the general formula Ca.sub.5 (SiO.sub.4).sub.2 CO.sub.3. A method for producing the synthetic CO.sub.2 acceptor is also disclosed.

  1. Doping and pressure study of U sub 3 Sb sub 4 Pt sub 3

    SciTech Connect (OSTI)

    Canfield, P.C.; Lacerda, A.; Thompson, J.D.; Sparn, G.; Beyermann, W.P.; Hundley, M.F.; Fisk, Z.

    1991-01-01T23:59:59.000Z

    The effects of doping and pressure on the U{sub 3}Sb{sub 4}Pt{sub 3} system have been studied. Substitution of either trivalent Y or Lu for U causes significant changes in temperature dependence of the electrical resistance and magnitude of the linear coefficient of the specific heat, {gamma}. However, doping with tetravalent Th causes little change in {gamma}, even though it affects the electrical resistance in a manner similar to that seen in the cases of Lu and Y. Finally, the application of hydrostatic pressures up to 16.5 kbar causes no significant change in the electrical resistance. 10 refs., 4 figs.

  2. Fabrication of high-T sub c Josephson effect devices by natural lithography

    SciTech Connect (OSTI)

    Dozier, W.D.; Daly, K.P.; Hu, R.; Platt, C.E.; Wire, M.S. (TRW Space and Technology Group, Redondo Beach, CA (United States))

    1991-03-01T23:59:59.000Z

    This paper reports on deposited thin films of YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO) on LaAlO{sub 3} substrates previously textured with submicron which features by the use of natural lithography (the use of monolayers of polystyrene microspheres as lithographic masks). This weakens the superconducting properties due to reduced connectivity in the film. Devices fabricated using localized textured regions have shown Josephson coupling. Weak links have shown Shapiro steps at the expected voltage intervals. Magnetic field induced modulation in the detected RF voltage with the geometrically correct periodicity has been observed in RF SQUIDs over a limited temperature range.

  3. PlanetEarthWinter2002--www.nerc.ac.uk PlanetEarthWinter2002--www.nerc.ac.uk

    E-Print Network [OSTI]

    National Oceanography Centre, Southampton

    to carry out visual surveys, pipeline construction and general maintenance. In the seas to the west work class ROVs designed and operated by Subsea 7, called Centurion 21 and 30. There are also two

  4. NERC Environmental Travel Policy 1. NERC recognises that, although travel is an essential part of our business

    E-Print Network [OSTI]

    Brierley, Andrew

    be justified. Sharing a car with fellow travellers is also important as is selecting the most appropriate hire vehicle. · Private car ­ only when hire car option is not viable and share whenever possible · Air, rail and public transport ­ the preferred choice for essential medium to long journeys; · Hire car

  5. Vacancy-type defects in In{sub x}Ga{sub 1?x}N grown on GaN templates probed using monoenergetic positron beams

    SciTech Connect (OSTI)

    Uedono, Akira [Division of Applied Physics, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Watanabe, Tomohito; Kimura, Shogo; Zhang, Yang; Lozac'h, Mickael [Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Sang, Liwen; Sumiya, Masatomo [Wide Bandgap Material Group, National Institute for Materials Science, Tsukuba 305-0044 (Japan); Ishibashi, Shoji [Nanosystem Research Institute (NRI) “RICS,” National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Oshima, Nagayasu; Suzuki, Ryoichi [Research Institute of Instrumentation Frontier, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568 (Japan)

    2013-11-14T23:59:59.000Z

    Native defects in In{sub x}Ga{sub 1?x}N layers grown by metalorganic chemical vapor deposition were studied using monoenergetic positron beams. Measurements of Doppler broadening spectra of the annihilation radiation and lifetime spectra of positrons for a 200-nm-thick In{sub 0.13}Ga{sub 0.87}N layer showed that vacancy-type defects were introduced by InN alloying, and the major species of such defects was identified as complexes between a cation vacancy and nitrogen vacancies. The presence of the defects correlated with lattice relaxation of the In{sub 0.13}Ga{sub 0.87}N layer and the increase in photon emissions from donor-acceptor-pair recombination. The species of native defects in In{sub 0.06}Ga{sub 0.94}N layers was the same but its concentration was decreased by decreasing the InN composition. With the layer thickness increased from 120?nm to 360?nm, a defect-rich region was introduced in the subsurface region (<160?nm), which can be associated with layer growth with the relaxation of compressive stress.

  6. Lead (II) selenite halides Pb{sub 3}(SeO{sub 3}){sub 2}X{sub 2} (X = Br, I): Synthesis and crystal structure

    SciTech Connect (OSTI)

    Berdonosov, P. S., E-mail: berdonosov@inorg.chem.msu.ru; Olenev, A. V.; Dolgikh, V. A. [Moscow State University (Russian Federation)

    2012-03-15T23:59:59.000Z

    Two lead selenite halides, Pb{sub 3}(SeO{sub 3}){sub 2}Br{sub 2} and Pb{sub 3}(SeO{sub 3}){sub 2}I{sub 2}, have been prepared by solid-phase synthesis and structurally characterized. These compounds are isotypic and can be considered 3D with a microporous framework composed of lead polyhedra (distorted Archimedean antiprisms formed by oxygen and halogen atoms). The framework contains channels oriented in the [010] direction. These channels contain selenium atoms, which are bound with framework oxygen atoms belonging to different lead polyhedra.

  7. Electronic structure and transport properties of Ba{sub 6}Cu{sub 12}Fe{sub 13}S{sub 27}

    SciTech Connect (OSTI)

    Llanos, J.; Mujica, C. [Univ. Catolica del Norte, Casilla (Chile). Dept. de Quimica] [Univ. Catolica del Norte, Casilla (Chile). Dept. de Quimica

    1997-09-01T23:59:59.000Z

    The electrical properties and bonding in Ba{sub 6}Cu{sub 12}Fe{sub 13}S{sub 27} are analyzed with the extended Hueckel tight-binding method. Because the Fermi level crosses several bands, metallic properties could be expected for this material. The electrical conductivity measurements as well as diffuse reflectance spectrum show that Ba{sub 6}Cu{sub 12}S{sub 13}S{sub 27} is a semiconductor with a band gap of 2.49 eV. The discrepancy between the theoretical and experimental electrical properties is attributed to a random distribution of the Cu and Fe atoms in the structure.

  8. Synthesis and crystal structure of 3-ammoniumphenyl sulfone selenate, 3-aminophenyl sulfone [C{sub 12}H{sub 14}N{sub 2}O{sub 2}S]SeO{sub 4} {center_dot} [C{sub 12}H{sub 12}N{sub 2}O{sub 2}S

    SciTech Connect (OSTI)

    Mahroug, A.; Belhouchet, M., E-mail: belhouchet2002@yahoo.fr; Mhiri, T. [Universite de Sfax, Laboratoire Physico-Chimie de l'Etat Solide. Departement de Chimie. Faculte des Sciences de Sfax (Tunisia)

    2013-07-15T23:59:59.000Z

    The crystal structure of [C{sub 12}H{sub 14}N{sub 2}O{sub 2}S]SeO{sub 4} {center_dot} [C{sub 12}H{sub 12}N{sub 2}O{sub 2}S] was determined by X-ray diffraction on single crystal. Crystals are orthorhombic, space group Pbca, with cell parameters a = 11.545 (1), b = 8.143 (1), c = 55.783(1)A, V = 5244.2 (8)A{sup 3} and Z = 8. The structure can be described as organic layers built by [C{sub 12}H{sub 14}N{sub 2}O{sub 2}S]{sup 2+} cations and [C{sub 12}H{sub 12}N{sub 2}O{sub 2}S] molecules, parallel to ab plane, between which the inorganic groups SeO{sub 4}{sup 2-} are inserted. In this atomic arrangement, H-bonds between the different species play an important role in the three-dimensional network cohesion.

  9. Twofold enhancement of the hidden-order/large-moment antiferromagnetic phase boundary in the URu<sub>2-xsub>Fex>Si? system

    SciTech Connect (OSTI)

    Kanchanavatee, N.; Janoschek, M.; Baumbach, R. E.; Hamlin, J. J.; Zocco, D. A.; Huang, K.; Maple, M. B.

    2011-12-01T23:59:59.000Z

    Electrical resistivity, specific heat, and magnetization measurements on URu<sub>2-xsub>Fex>Si? reveal a twofold enhancement of the “hidden-order” (HO)/large-moment antiferromagnetic (LMAFM) phase boundary T?(x). The T?(P<sub>ch>) curve, obtained by converting x to “chemical pressure” P<sub>ch>, is strikingly similar to the T?(P) curve, where P is applied pressure, for URu?Si? both exhibit a “kink” at 1.5 GPa and a maximum at ~7 GPa. This similarity suggests that the HO-LMAFM transition at 1.5 GPa in URu?Si? occurs at x ? 0.2 (P<sub>ch>?1.5 GPa) in URu<sub>2-xsub>Fex>Si?. URu<sub>2-xsub>Fex>Si? provides an opportunity for studying the HO and LMAFM phases with methods that probe the electronic structure [e.g., scanning tunneling microscopy (STM), angle-resolved photoemission spectroscopy (ARPES), and point-contact spectroscopy (PCS)] but cannot be used under pressure.

  10. Topologically identical, but geometrically isomeric layers in hydrous ?-, ?-Rb[UO{sub 2}(AsO{sub 3}OH)(AsO{sub 2}(OH){sub 2})]·H{sub 2}O and anhydrous Rb[UO{sub 2}(AsO{sub 3}OH)(AsO{sub 2}(OH){sub 2})

    SciTech Connect (OSTI)

    Yu, Na; Klepov, Vladislav V. [Forschungszentrum Jülich GmbH, Institute for Energy and Climate Research (IEK-6), 52428 Jülich (Germany); Villa, Eric M. [Department of Chemistry, Creighton University, 2500 California Plaza, Omaha NE 68178 (United States); Bosbach, Dirk [Forschungszentrum Jülich GmbH, Institute for Energy and Climate Research (IEK-6), 52428 Jülich (Germany); Suleimanov, Evgeny V. [Department of Chemistry, Lobachevsky State University of Nizhny Novgorod, 603950 Nizhny Novgorod (Russian Federation); Depmeier, Wulf [Institut für Geowissenschaften, Universität zu Kiel, 24118 Kiel (Germany); Albrecht-Schmitt, Thomas E., E-mail: albrecht-schmitt@chem.fsu.edu [Department of Chemistry and Biochemistry, Florida State University, 102 Varsity Way, Tallahassee, FL 32306-4390 (United States); Alekseev, Evgeny V., E-mail: e.alekseev@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute for Energy and Climate Research (IEK-6), 52428 Jülich (Germany); Institut für Kristallographie, RWTH Aachen University, 52066 Aachen (Germany)

    2014-07-01T23:59:59.000Z

    The hydrothermal reaction of uranyl nitrate with rubidium nitrate and arsenic (III) oxide results in the formation of polymorphic ?- and ?-Rb[UO{sub 2}(AsO{sub 3}OH)(AsO{sub 2}(OH){sub 2})]·H{sub 2}O (?-, ?-RbUAs) and the anhydrous phase Rb[UO{sub 2}(AsO{sub 3}OH)(AsO{sub 2}(OH){sub 2})] (RbUAs). These phases were structurally, chemically and spectroscopically characterized. The structures of all three compounds are based upon topologically identical, but geometrically isomeric layers. The layers are linked with each other by means of the Rb cations and hydrogen bonding. Dehydration experiments demonstrate that water deintercalation from hydrous ?- and ?-RbUAs yields anhydrous RbUAs via topotactic reactions. - Graphical abstract: Three different layer geometries observed in the structures of Rb[UO{sub 2}(AsO{sub 3}OH)(AsO{sub 2}(OH){sub 2})] and ?- and ?- Rb[UO{sub 2}(AsO{sub 3}OH)(AsO{sub 2}(OH){sub 2})]·H{sub 2}O. Two different coordination environments of uranium polyhedra (types I and II) are shown schematically on the top of the figure. - Highlights: • Three new uranyl arsenates were synthesized from the hydrothermal reactions. • The phases consist of the topologically identical but geometrically different layers. • Topotactic transitions were observed in the processes of mono-hyrates dehydration.

  11. Misfit layered Ca{sub 3}Co{sub 4}O{sub 9} as a high figure of merit p-type transparent conducting oxide film through solution processing

    SciTech Connect (OSTI)

    Aksit, M.; Kolli, S. K.; Slauch, I. M.; Robinson, R. D., E-mail: rdr82@cornell.edu [Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States)

    2014-04-21T23:59:59.000Z

    Ca{sub 3}Co{sub 4}O{sub 9} thin films synthesized through solution processing are shown to be high-performing, p-type transparent conducting oxides (TCOs). The synthesis method is a cost-effective and scalable process that consists of sol-gel chemistry, spin coating, and heat treatments. The process parameters can be varied to produce TCO thin films with sheet resistance as low as 5.7?k?/sq (????57 m? cm) or with average visible range transparency as high as 67%. The most conductive Ca{sub 3}Co{sub 4}O{sub 9} TCO thin film has near infrared region optical transmission as high as 85%. The figure of merit (FOM) for the top-performing Ca{sub 3}Co{sub 4}O{sub 9} thin film (151 M?{sup ?1}) is higher than FOM values reported in the literature for all other solution processed, p-type TCO thin films and higher than most others prepared by physical vapor deposition and chemical vapor deposition. Transparent conductivity in misfit layered oxides presents new opportunities for TCO compositions.

  12. Effect of diamagnetic barium substitution on magnetic and photovoltaic properties in multiferroic BiFeO{sub 3}

    SciTech Connect (OSTI)

    Hung, C.-M. [Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Tu, C. S., E-mail: 039611@mail.fju.edu.tw [Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Department of Physics, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Xu, Z.-R.; Chang, L.-Y. [Department of Physics, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China); Schmidt, V. H.; Chien, R. R. [Department of Physics, Montana State University, Bozeman, Montana 59717 (United States); Chang, W. C. [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China)

    2014-05-07T23:59:59.000Z

    Spontaneous magnetization and photovoltaic (PV) effects have been measured in (Bi{sub 1-x}Ba{sub x})FeO{sub 3-?} ceramics for x?=?0.05, 0.10, and 0.15. The substitution of Ba{sup 2+} ion in the A site of the perovskite unit cell can effectively enhance the ferromagnetic magnetization. The heterostructure of indium tin oxide (ITO) film/(Bi{sub 1-x}Ba{sub x})FeO{sub 3-?} ceramic/Au film exhibits significant PV effects under illumination of ??=?405?nm. The PV responses decrease with increasing Ba concentration. The maximum power-conversion efficiency in the ITO/(Bi{sub 0.95}Ba{sub 0.5})FeO{sub 2.95}/Au can reach 0.006%. A theoretical model based on optically excited current in the depletion region between ITO film and (Bi{sub 1-x}Ba{sub x})FeO{sub 3-?} ceramics is used to describe the I-V characteristic, open-circuit voltage (V{sub oc}), and short-circuit current density (J{sub sc}) as a function of light intensity.

  13. Cobalt-doped Bi{sub 26}Mo{sub 10}O{sub 69}: Crystal structure and conductivity

    SciTech Connect (OSTI)

    Mikhailovskaya, Z.A., E-mail: zozoikina@mail.ru [Ural Federal University, Lenin Ave. 51, 620000 Ekaterinburg (Russian Federation); Buyanova, E.S. [Ural Federal University, Lenin Ave. 51, 620000 Ekaterinburg (Russian Federation); Petrova, S.A. [Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences, 101 Amundsen Str., 620016 Ekaterinburg (Russian Federation); Morozova, M.V.; Zhukovskiy, V.M. [Ural Federal University, Lenin Ave. 51, 620000 Ekaterinburg (Russian Federation); Zakharov, R.G. [Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences, 101 Amundsen Str., 620016 Ekaterinburg (Russian Federation); Tarakina, N.V. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 91 Pervomayskaya Str., 620990 Ekaterinburg (Russian Federation); Experimentelle Physik III, Physikalisches Institut and Wilhelm Conrad Röntgen—Research Centre for Complex Material Systems, Universität Würzburg, Am Hubland, D-97074 Würzburg (Germany); Berger, I.F. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 91 Pervomayskaya Str., 620990 Ekaterinburg (Russian Federation)

    2013-08-15T23:59:59.000Z

    A series of cobalt-doped bismuth molybdates were synthesized and investigated using X-ray powder diffraction, transmission electron microscopy and impedance spectroscopy. The ranges of solid solution were determined. Two new compounds, Bi{sub 1?x}Co{sub x}[Bi{sub 12}O{sub 14}]Mo{sub 5}O{sub 34.5±?} (x=0.2) and Bi[Bi{sub 12}O{sub 14}]Mo{sub 5?y}Co{sub y}O{sub 34.5±?} (y=0.2), which crystallise in monoclinic unit cells have been examined in detail by diffraction methods. Impedance spectroscopy measurements show that the studied materials are good ionic conductors with conductivity values about 5×10{sup ?3} S×cm{sup ?1} at 973 K and 1.7×10{sup ?4} S×cm{sup ?1} at 623 K, which are similar to conductivity values of yttrium substituted zirconia and (YSZ) gadolinium doped ceria (CGO). - Graphical abstract: Measured and calculated diffraction spectra for Bi{sub 12.8}Co{sub 0.2}Mo{sub 5}O{sub 34±?} and projection of the Bi{sub 12.8}Co{sub 0.2}Mo{sub 5}O{sub 34±?} crystal structure onto the ac plane. Highlights: • The limit of the Bi{sub 1?x}Co{sub x}[Bi{sub 12}O{sub 14}]Mo{sub 5}O{sub 34.5±?} homogeneity range is equal to x=0.2. • The limit of the Bi[Bi{sub 12}O{sub 14}]Mo{sub 5?y}Co{sub y}O{sub 34.5±?} homogeneity range is equal to y=0.2. • Solid solutions have monoclinic symmetry. No phase transition is observed. • The conductivity at 700° for y=0.2 solid solutions is equal to ?lg ?, S×cm{sup ?1}=2.23. • The conductivity at 350° for y=0.2 solid solutions is equal to ?lg ?, S×cm{sup ?1}=3.74.

  14. Role of SrMoO{sub 4} in Sr{sub 2}MgMoO{sub 6} synthesis

    SciTech Connect (OSTI)

    Vasala, S.; Yamauchi, H. [Laboratory of Inorganic Chemistry, Department of Chemistry, School of Chemical Technology, Aalto University, P.O. Box 16100, FI-00076 Aalto (Finland); Karppinen, M., E-mail: maarit.karppinen@aalto.f [Laboratory of Inorganic Chemistry, Department of Chemistry, School of Chemical Technology, Aalto University, P.O. Box 16100, FI-00076 Aalto (Finland)

    2011-05-15T23:59:59.000Z

    Here we investigate the elemental and phase compositions during the solid-state synthesis of the promising SOFC-anode material, Sr{sub 2}MgMoO{sub 6}, and demonstrate that molybdenum does not notably evaporate under the normal synthesis conditions with temperatures up to 1200 {sup o}C due to the formation of SrMoO{sub 4} as an intermediate product at low temperatures, below 600 {sup o}C. However, partial decomposition of the Sr{sub 2}MgMoO{sub 6} phase becomes evident at the higher temperatures ({approx}1500 {sup o}C). The effect of SrMoO{sub 4} on the electrical conductivity of Sr{sub 2}MgMoO{sub 6} is evaluated by preparing a series of Sr{sub 2}MgMoO{sub 6} samples with different amounts of additional SrMoO{sub 4}. Under the reducing operation conditions of an SOFC anode the insulating SrMoO{sub 4} phase is apparently reduced to the highly conductive SrMoO{sub 3} phase. Percolation takes place with 20-30 wt% of SrMoO{sub 4} in a Sr{sub 2}MgMoO{sub 6} matrix, with a notable increase in electrical conductivity after reduction. Conductivity values of 14, 60 and 160 S/cm are determined at 800 {sup o}C in 5% H{sub 2}/Ar for the Sr{sub 2}MgMoO{sub 6} samples with 30, 40 and 50 wt% of added SrMoO{sub 4}, respectively. -- Graphical abstract: SrMoO{sub 4} is formed at low temperatures during the synthesis of Sr{sub 2}MgMoO{sub 6}, which prevents the volatilization of Mo from typical precursor mixtures of this promising SOFC anode material. SrMoO{sub 4} is insulating and it is often found as an impurity in Sr{sub 2}MgMoO{sub 6} samples. It is however readily reduced to highly conducting SrMoO{sub 3}. Composites of Sr{sub 2}MgMoO{sub 6} and SrMoO{sub 3} show increased electrical conductivities compared to pure Sr{sub 2}MgMoO{sub 6} under the reductive operation conditions of an SOFC anode. Display Omitted Highlights: {yields} Sr{sub 2}MgMoO{sub 6} is a promising SOFC anode material. {yields} During the Sr{sub 2}MgMoO{sub 6} synthesis SrMoO{sub 4} is formed at low temperatures. {yields} Formation of SrMoO{sub 4} effectively prevents volatilization of Mo at high temperatures. {yields} Insulating SrMoO{sub 4} reduces to highly conductive SrMoO{sub 3} under SOFC-anode conditions. {yields} Composites of Sr{sub 2}MgMoO{sub 6} and SrMoO{sub 3} show high electrical conductivities.

  15. Hydrogen-bridge trinuclear nitrosyl carbonyl tungstate: H[sub 2]W[sub 3](CO)[sub 13](NO)[sup [minus

    SciTech Connect (OSTI)

    Jiann T. Lin; Yuh S. Wen (Academia Sinica, Nankang, Taipei Taiwan (China)); Shiow Y. Wang (Private Chung Chou Junior College of Technology and Commerce, Chung Hau Taiwan (China)); An C. Yeh; Thamas Y.R. Tsai (Chun-Yuan Christian Univ., Chung-Li, Taiwan (China)); Shie-Ming Peng; Lee, G.H. (National Tawian Univ., Taipei (China))

    1994-04-27T23:59:59.000Z

    Treatment of HW[sub 2](CO)[sub 7](THF)[sub 2](NO) with P[sup t]Bu[sub 3] gives HW[sub 2](CO)[sub 8](P[sup t]Bu[sub 3])(NO) (1), [HP[sup t]PBu[sub 3

  16. Synthesis, crystal structure and magnetic property of a new nickel selenite chloride: Ni{sub 5}(SeO{sub 3}){sub 4}Cl{sub 2}

    SciTech Connect (OSTI)

    Shen Yueling [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China); Mao Jianggao [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China)]. E-mail: mjg@ms.fjirsm.ac.cn; Jiang Hailong [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, and the Graduate School of the Chinese Academy of Sciences, Fuzhou 350002 (China)

    2005-09-15T23:59:59.000Z

    The new nickel selenite chloride, Ni{sub 5}(SeO{sub 3}){sub 4}Cl{sub 2}, was obtained by high-temperature solid state reaction of NiCl{sub 2}, Ni{sub 2}O{sub 3} and SeO{sub 2} in a 1:2:4molar ratio at 700{sup o}C in an evacuated quartz tube. Its structure was established by single-crystal X-ray diffraction. Ni{sub 5}(SeO{sub 3}){sub 4}Cl{sub 2} crystallizes in the triclinic system, space group P-1 (No. 2) with cell parameters of a=8.076(2), b=9.288(2), c=9.376(2)A, {alpha}=101.97(3), {beta}=105.60(3), {gamma}=91.83(3){sup o} and Z=2. All nickel(II) ions in Ni{sub 5}(SeO{sub 3}){sub 4}Cl{sub 2} are octahedrally coordinated by selenite oxygens or/and chloride anions (([Ni(1)O{sub 5}Cl], [Ni(2)O{sub 4}Cl{sub 2}], [Ni(3)O{sub 5}Cl], [Ni(4)O{sub 6}] and [Ni(5)O{sub 4}Cl]). The structure of the title compound features a condensed three-dimensional (3D) network built by Ni(II) ions interconnected by SeO{sub 3}{sup 2-} anions as well as Cl{sup -} anions. Magnetic property measurements show strong antiferromagnetic interaction between nickel(II) ions.

  17. SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6} - two new Ae-Zn-Sn polar intermetallic compounds (Ae: alkaline earth metal)

    SciTech Connect (OSTI)

    Stegmaier, Saskia [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstrasse 4, 85747 Garching (Germany); Faessler, Thomas F., E-mail: Thomas.Faessler@lrz.tum.de [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstrasse 4, 85747 Garching (Germany)

    2012-08-15T23:59:59.000Z

    SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6}, two closely related new polar intermetallic compounds, were obtained by high temperature reactions of the elements. Their crystal structures were determined with single crystal XRD methods, and their electronic structures were analyzed by means of DFT calculations. The Zn-Sn structure part of SrZn{sub 2}Sn{sub 2} comprises (anti-)PbO-like {l_brace}ZnSn{sub 4/4}{r_brace} and {l_brace}SnZn{sub 4/4}{r_brace} layers. Ca{sub 2}Zn{sub 3}Sn{sub 6} shows similar {l_brace}ZnSn{sub 4/4}{r_brace} layers and {l_brace}Sn{sub 4}Zn{r_brace} slabs constructed of a covalently bonded Sn scaffold capped by Zn atoms. For both phases, the two types of layers are alternatingly stacked and interconnected via Zn-Sn bonds. SrZn{sub 2}Sn{sub 2} adopts the SrPd{sub 2}Bi{sub 2} structure type, and Ca{sub 2}Zn{sub 3}Sn{sub 6} is isotypic to the R{sub 2}Zn{sub 3}Ge{sub 6} compounds (R=La, Ce, Pr, Nd). Band structure calculations indicate that both SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6} are metallic. Analyses of the chemical bonding with the electron localization function (ELF) show lone pair like basins at Sn atoms and Zn-Sn bonding interactions between the layers for both title phases, and covalent Sn-Sn bonding within the {l_brace}Sn{sub 4}Zn{r_brace} layers of Ca{sub 2}Zn{sub 3}Sn{sub 6}. - Graphical abstract: Crystal structures of the new Ae-Zn-Sn polar intermetallic phases SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6}. Highlights: Black-Right-Pointing-Pointer New polar intermetallic phases SrZn{sub 2}Sn{sub 2} and Ca{sub 2}Zn{sub 3}Sn{sub 6}. Black-Right-Pointing-Pointer Obtained by high temperature reactions of the elements. Black-Right-Pointing-Pointer Single crystal XRD structure determination and DFT electronic structure calculations. Black-Right-Pointing-Pointer Closely related crystal and electronic structures. Black-Right-Pointing-Pointer Metallic conductivity coexisting with lone pairs and covalent bonding features.

  18. Temperature-dependent framework–template interaction of |Na{sub 6}(H{sub 2}O){sub 8}|[ZnPO{sub 4}]{sub 6} sodalite

    SciTech Connect (OSTI)

    Robben, Lars, E-mail: lrobben@uni-bremen.de; Gesing, Thorsten M.

    2013-11-15T23:59:59.000Z

    The partial dehydration followed by the decomposition of sodium-zincophosphate-hydrosodalite caused by the total water loss was examined by temperature-dependent X-ray powder diffraction, Fourier transform infrared (FTIR) and Raman spectroscopy as well as thermogravimetry combined with difference thermoanalysis. The dehydration causing the decomposition of this sodalite could be described in a two step-process. Initially two water molecules per unit-cell were lost, changing the interaction between the zincophosphate framework and the remaining water molecules as well as sodium cations as non-framework constituents. In this stage a 3+3 coordination of water molecules and sodium cations in the sodalite cage is observed. Using the autocorrelation function (AC) for the evaluation of the temperature-dependent FTIR spectra of sodalites is reported here for the first time. Calculating the changes in the AC broadness, structural features could well be analyzed due to its correlation with respective structural parameters. Temperature dependent Raman data was used to give a band assignment of bands at Raman shifts below 300 cm{sup ?1}. - Graphical abstract: The thermal decomposition of |Na{sub 6}(H{sub 2}O){sub 8}|[ZnPO{sub 4}]{sub 6} sodalite is a two-step process with an initial loss of two water molecules at 400 K, intermediately stabilizing the highly stressed framework. Further heating leads to a subsequent loss of the remaining six water molecules and a breakup of the sodalite framework. A beryllonite-type NaZnPO{sub 4} is the final product of this process. Display Omitted - Highlights: • The decomposition of |Na{sub 6}(H{sub 2}O){sub 8}|[ZnPO{sub 4}]{sub 6} sodalite is a two-step process. • Initial loss of two water molecule at 400 K stabilizes the sodalite (step 1). • Further heating leads to complete loss of water and structural breakdown. • Autocorrelation of temperature dependent FTIR-spectra gives structural information.

  19. Defect production in strained p-type Si{sub 1-x}Ge{sub x} by Er implantation

    SciTech Connect (OSTI)

    Mamor, M. [Instituut voor Kern-en Stralingsfysica and INPAC, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Department of Physics, Sultan Qaboos University, P.O. Box 50, Muscat 123, Sultanate of Oman (Oman); Pipeleers, B.; Vantomme, A. [Instituut voor Kern-en Stralingsfysica and INPAC, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Auret, F. D. [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa)

    2011-01-01T23:59:59.000Z

    Strained p-Si{sub 1-x}Ge{sub x} (x=5.3%, 10.2%, and 15.4%) was irradiated at room temperature with 160 keV {sup 166}Er{sup 2+} ions to a fluence of 1x10{sup 10} or 3x10{sup 13} Er/cm{sup 2}. The defects induced by ion implantation were investigated experimentally using high-resolution x-ray diffraction, Rutherford backscattering and channeling spectroscopy, and deep level transient spectroscopy. X-ray diffraction indicates that the damage induced by Er implantation produces a slight perpendicular expansion of the SiGe lattice. For all compositions, channeling measurements reveal that Er implantation in p-Si{sub 1-x}Ge{sub x} to a fluence of 3x10{sup 13} Er/cm{sup 2} induces an amorphous region below the Si{sub 1-x}Ge{sub x} surface. Annealing at 850 deg. C for 30 s, results in a reduction in damage density, a relaxation of the implantation-induced perpendicular expansion of the SiGe lattice in the implanted region, while a more pronounced relaxation of the compressive strain SiGe is observed for higher Ge content (x=0.10 and 0.15). On the other hand, for the annealed SiGe samples that were implanted with Er at the fluence of 10{sup 10} Er/cm{sup 2}, the compressive strain in the SiGe layer is nearly completely retained. Deep level transient spectroscopy studies indicate that two prominent defects with discrete energy levels above the valence band are introduced during Er implantation. Their activation energy was found to decrease with increasing Ge content. However, the relatively large local strain induced by high fluence Er implantation reduces the activation energy by 40 meV with respect to the low fluence Er implanted p-Si{sub 1-x}Ge{sub x}. This shift (40 meV) in the activation energy remains constant regardless of the Ge content, suggesting that the Si{sub 1-x}Ge{sub x} layers remained fully strained after Er implantation. The observed defects are further compared to those introduced by alpha particle irradiation and electron beam metal deposition. The results indicate that defects introduced by Er implantation have similar electronic properties as those of defects detected after electron beam deposition and alpha particle irradiation. Therefore, it is concluded that these defects are due to the Er implantation-induced damage and not to the Er species specifically.

  20. A cluster with a mixed M{sub 6}X{sub 12}/M{sub 6}X{sub 8} environment: The La{sub 6}Cl{sub 11}Co structure

    SciTech Connect (OSTI)

    Zheng Chong, E-mail: czheng@niu.ed [Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, IL 60115 (United States); Mattausch, Hansjuergen; Hoch, Constantin; Simon, Arndt [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany)

    2009-08-15T23:59:59.000Z

    The title compound was synthesized from La, LaCl{sub 3} and Co under Ar atmosphere at 800 deg. C. It crystallizes in space group P4{sub 2}/n (no. 86) with lattice constants a=11.308(2) A and c=14.441(3) A. The structure features an isolated Co-centered La{sub 6} octahedron with all corners and edges, and 2 of its 8 triangular faces coordinated by Cl atoms. The La{sub 6}Co octahedron is significantly distorted, and the La coordination by Cl atoms deviates from the common close-packing arrangements found in other reduced rare earth metal halides. Structure, bonding and physical properties of the compound have been investigated. - Graphical abstract: La{sub 6}Cl{sub 11}Co octahedron exhibiting a mixed M{sub 6}X{sub 12}/M{sub 6}X{sub 12} coordination environment.

  1. Proton form factor ratio, {mu}{sub p}G{sub E}{sup P}/G{sub M}{sup P} from double spin asymmetry

    SciTech Connect (OSTI)

    Habarakada Liyanage, Anusha Pushpakumari [Hampton U., JLAB] [Hampton U., JLAB

    2013-08-01T23:59:59.000Z

    The form factors are fundamental properties of the nucleon representing the effect of its structure on its response to electromagnetic probes such as electrons. They are functions of the four-momentum transfer squared Q{sup 2} between the electron and the proton. This thesis reports the results of a new measurement of the ratio of the electric and magnetic form factors of the proton up to Q{sup 2} = 5.66 (GeV/c){sup 2} using the double spin asymmetry with a polarized beam and target. Experiment E07-003 (SANE, Spin Asymmetries of the Nucleon Experiment) was carried out in Hall C at Jefferson Lab in 2009 to study the proton spin structure functions with a dynamically polarized ammonia target and longitudinally polarized electron beam. By detecting elastically scattered protons in the High-Momentum Spectrometer (HMS) in coincidence with the electrons in the Big Electron Telescope Array (BETA), elastic measurements were carried out in parallel. The elastic double spin asymmetry allows one to extract the proton electric to magnetic form factor ratio G{sup p}{sub E}/G{sup p}{sub M} at high-momentum transfer, Q{sup 2} = 5.66 (GeV/c){sup 2}. In addition to the coincidence data, inclusively scattered electrons from the polarized ammonia target were detected by HMS, which allows to measure the beam-target asymmetry in the elastic region with the target spin nearly perpendicular to the momentum transfer, and to extract G{sup p}{sub E}/G{sup p}{sub M} at low Q{sup 2} = 2.06 (GeV/c){sup 2}. This alternative measurement of G{sup p}{sub E}/G{sup p}{sub M} has verified and confirmed the dramatic discrepancy at high Q{sup 2} between the Rosenbluth and the recoil-polarization-transfer iv method with a different measurement technique and systematic uncertainties uncorrelated to those of the recoil-polarization measurements. The measurement of the form factor ratio at Q{sup 2} = 2.06 (GeV/c){sup 2} has been determined as {mu}{sub p}G{sup p}{sub E}/G{sup p}{sub M} = 0.605{+-}0.178{sub stat}{+-}0.033{sub sys} which is in agreement with an earlier measurement with the polarized target technique at similar kinematics. The measurement of the form factor ratio at Q{sup 2} = 5.66 (GeV/c){sup 2} has been determined as {mu}{sub p}G{sup p}{sub E}/G{sup p}{sub M} = 0.672 {+-} 0.362{sub stat} which represents the highest Q{sup 2} reach with the double spin asymmetry to date.

  2. Symmetry determination on Pb-free piezoceramic 0.5Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}-0.5(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} using convergent beam electron diffraction method

    SciTech Connect (OSTI)

    Gao, Jinghui, E-mail: gaojinghui@mail.xjtu.edu.cn; Zhong, Lisheng [Multi-Disciplinary Materials Research Center, State Key Lab of Electrical Insulation and Power Equipment and Frontier Institute of Science and Technology, Xi'an, 710049 (China); Zhang, Lixue; Xue, Dezhen [Multi-Disciplinary Materials Research Center, State Key Lab of Electrical Insulation and Power Equipment and Frontier Institute of Science and Technology, Xi'an, 710049 (China); State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049 (China); Kimoto, Takayoshi [Ferroic Physics Group, National Institute for Materials Science, Tsukuba, 305-0047, Ibaraki (Japan); Song, Minghui [Electron Microscopy Group, National Institute for Materials Science, Tsukuba, 305-0047, Ibaraki (Japan); Ren, Xiaobing [Multi-Disciplinary Materials Research Center, State Key Lab of Electrical Insulation and Power Equipment and Frontier Institute of Science and Technology, Xi'an, 710049 (China); State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049 (China); Ferroic Physics Group, National Institute for Materials Science, Tsukuba, 305-0047, Ibaraki (Japan)

    2014-02-07T23:59:59.000Z

    (1?x)(Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}-x(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} (BZT-xBCT) Pb-free piezoceramic has been reported showing ultrahigh piezoelectric performance in its morphotropic phase boundary (MPB) region. However, the crystal structure characteristic for the MPB composition of BZT-xBCT is still under debate—between single orthorhombic phase and tetragonal + rhombohedral two phase mixture. In the present study, we perform the local symmetry determination on the MPB composition x = 0.5 using convergent beam electron diffraction analysis (CBED). Our CBED results from multiple zone axes suggest that there are two coexisting phases with the point group symmetries of 4?mm (tetragonal) and 3?m (rhombohedral) respectively, which agree with two phase mixture model. The strong piezoelectricity can thus be understood by considering the polarization rotation between tetragonal and rhombohedral phases by external field.

  3. Crystal-chemistry of mullite-type aluminoborates Al{sub 18}B{sub 4}O{sub 33} and Al{sub 5}BO{sub 9}: A stoichiometry puzzle

    SciTech Connect (OSTI)

    Fisch, Martin, E-mail: fisch@krist.unibe.c [Mineralogical Crystallography, Institute of Geological Sciences, University of Bern, Freiestrasse 3, CH-3012 Bern (Switzerland); Armbruster, Thomas [Mineralogical Crystallography, Institute of Geological Sciences, University of Bern, Freiestrasse 3, CH-3012 Bern (Switzerland); Rentsch, Daniel [EMPA, Swiss Federal Laboratories for Materials Science and Research, Laboratory for Functional Polymers, Uberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Libowitzky, Eugen [Institut fuer Mineralogie und Kristallographie, Universitaet Wien - Geozentrum, Althanstrasse 14, A-1090 Wien (Austria); Pettke, Thomas [Rock-Water Interaction Group, Institute of Geological Sciences, University of Bern, Baltzerstrasse 1-3, CH-3012 Bern (Switzerland)

    2011-01-15T23:59:59.000Z

    Orthorhombic Al{sub 2}O{sub 3}-rich aluminoborate is an important ceramic material for which two slightly different compositions have been assumed: Al{sub 5}BO{sub 9} (5Al{sub 2}O{sub 3}:B{sub 2}O{sub 3}) and Al{sub 18}B{sub 4}O{sub 33} (9Al{sub 2}O{sub 3}:2B{sub 2}O{sub 3}). The formula Al{sub 18}B{sub 4}O{sub 33} (=Al{sub 4.91}B{sub 1.09}O{sub 9}) was derived from results of chemical analyses when crystal structure data were not yet available. Subsequent structural investigations indicated Al{sub 5}BO{sub 9} composition. Nevertheless, Al{sub 18}B{sub 4}O{sub 33} was still accepted as the correct stoichiometry assuming that additional B replaces 9% Al. Powder samples of both compositions and ones with excess boron were prepared by solid state reactions between {alpha}-Al{sub 2}O{sub 3} and B{sub 2}O{sub 3}/H{sub 3}BO{sub 3} at temperatures above 1100 {sup o}C and single-crystals were grown from flux at 1100 and 1550 {sup o}C. Products were investigated by single-crystal and powder XRD, {sup 11}B and {sup 27}Al solid-state MAS-NMR, Raman and FTIR spectroscopy as well as Laser-ablation ICP-MS. No indication of the predicted 9% B{yields}Al substitution was found. LA ICP-MS indicated 12.36(27) wt% B{sub 2}O{sub 3} corresponding to Al{sub 4.97}B{sub 1.03}O{sub 9}. Hence, the suggested Al{sub 18}B{sub 4}O{sub 33} stoichiometry can be excluded for all synthesized samples. A very low amount of Al vacancies at a five-fold coordinated site are likely, charge balanced by an additional nearby three-fold coordinated B site. All evidences indicate that the title compound should be reported as Al{sub 5-x}B{sub 1+x}O{sub 9} with x<0.038(6), which is close to Al{sub 5}BO{sub 9}. -- Graphical abstract: A chemical composition of Al{sub 18}B{sub 4}O{sub 33}=Al{sub 4.91}B{sub 1.09}O{sub 9}=9Al{sub 2}O{sub 3}:2B{sub 2}O{sub 3} has been assumed for mullite-type aluminoborate with Al{sub 5}BO{sub 9} structure. However, samples prepared by different routes showed compositions close to 5Al{sub 2}O{sub 3}:B{sub 2}O{sub 3}. Display Omitted

  4. H{sub 2}CO AND N{sub 2}H{sup +} IN PROTOPLANETARY DISKS: EVIDENCE FOR A CO-ICE REGULATED CHEMISTRY

    SciTech Connect (OSTI)

    Qi, Chunhua; Wilner, David J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Oeberg, Karin I. [Departments of Chemistry and Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)] [Departments of Chemistry and Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)

    2013-03-01T23:59:59.000Z

    We present Submillimeter Array (SMA) observations of H{sub 2}CO and N{sub 2}H{sup +} emission in the disks around the T Tauri star TW Hya and the Herbig Ae star HD 163296 at 2''-6'' resolution and discuss the distribution of these species with respect to CO freezeout. The H{sub 2}CO and N{sub 2}H{sup +} emission toward HD 163296 does not peak at the continuum emission center that marks the stellar position but is instead significantly offset. Using a previously developed model for the physical structure of this disk, we show that the H{sub 2}CO observations are reproduced if H{sub 2}CO is present predominantly in the cold outer disk regions. A model where H{sub 2}CO is present only beyond the CO snow line (estimated at a radius of 160 AU) matches the observations well. We also show that the average H{sub 2}CO excitation temperature, calculated from two transitions of H{sub 2}CO observed in these two disks and a larger sample of disks around T Tauri stars in the DISCS (the Disk Imaging Survey of Chemistry with SMA) program, is consistent with the CO freezeout temperature of {approx}20 K. In addition, we show that N{sub 2}H{sup +} and H{sub 2}CO line fluxes in disks are strongly correlated, indicative of co-formation of these species across the sample. Taken together, these results imply that H{sub 2}CO and N{sub 2}H{sup +} are generally present in disks only at low temperatures where CO depletes onto grains, consistent with fast destruction of N{sub 2}H{sup +} by gas-phase CO, and in situ formation of H{sub 2}CO through hydrogenation of CO ice. In this scenario H{sub 2}CO, CH{sub 3}OH, and N{sub 2}H{sup +} emission in disks should appear as rings with the inner edge at the CO midplane snow line. This prediction can be tested directly using observations from ALMA with higher resolution and better sensitivity.

  5. Synthesis of hexagonal Zn{sub 3}(OH){sub 2}V{sub 2}O{sub 7}·2H{sub 2}O nanoplates by a hydrothermal approach: Magnetic and photocatalytic properties

    SciTech Connect (OSTI)

    Wang, Fangfang; Wu, Wenbin; Sun, Xiujuan [College of Chemistry, Northeast Normal University, Changchun 130024 (China); Song, Shuyan [State Key Laboratory of Rare Earth Resource Utilizations, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Xing, Yan, E-mail: xingy202@nenu.edu.cn [College of Chemistry, Northeast Normal University, Changchun 130024 (China); Wang, Jiawei; Yu, Donghui; Su, Zhongmin [College of Chemistry, Northeast Normal University, Changchun 130024 (China)

    2013-12-15T23:59:59.000Z

    Hexagonal Zn{sub 3}(OH){sub 2}V{sub 2}O{sub 7}·2H{sub 2}O nanoplates have been successfully synthesized via a facile and template-free hydrothermal method. The nanocrystals have a hexagonal shape with 650–750 nm in diameter and 120–140 nm in thickness. The possible mechanism of forming such hexagonal Zn{sub 3}(OH){sub 2}V{sub 2}O{sub 7}·2H{sub 2}O nanoplates may be due to its inherent anisotropic crystal structure. Magnetic hysteresis measurement indicates that the as-synthesized hexagonal Zn{sub 3}(OH){sub 2}V{sub 2}O{sub 7}·2H{sub 2}O nanoplates have weak ferromagnetic property at room temperature. Compared to the floriated-like nanostructured Zn{sub 3}V{sub 2}O{sub 7}(OH){sub 2}(H{sub 2}O){sub 2} synthesized by a hydrothermal route, the as-prepared hexagonal Zn{sub 3}(OH){sub 2}V{sub 2}O{sub 7}·2H{sub 2}O nanoplates exhibited a significant increase in the methylene blue (MB) photodegradation rate under UV irradiation. Highlights: • Hexagonal Zn{sub 3}(OH){sub 2}V{sub 2}O{sub 7}·2H{sub 2}O nanoplates was synthesized via a hydrothermal method. • Magnetic study indicates that the nanoplates are of weak ferromagnetic property at room temperature. • The nanoplates exhibit greatly enhanced activity in the UV-light photocatalytic degradation of methylene blue.

  6. Visible light photocatalytic degradation of 4-chlorophenol using vanadium and nitrogen co-doped TiO{sub 2}

    SciTech Connect (OSTI)

    Jaiswal, R.; Kothari, D. C. [Department of Physics, University of Mumbai, Vidyanagari, Santacruz (E), Mumbai 400 098 (India); Patel, N.; Miotello, A. [Dipartimento di Fisica, Universita degli Studi di Trento, I-38123 Povo ( Trento) (Italy)

    2013-02-05T23:59:59.000Z

    Vanadium and Nitrogen were codoped in TiO{sub 2} photocatalyst by Sol-gel method to utilize visible light more efficiently for photocatalytic reactions. A noticeable shift of absorption edge to visible light region was obtained for the singly-doped namely V-TiO{sub 2}, N-TiO{sub 2} and codoped V-N-TiO{sub 2} samples in comparison with undoped TiO{sub 2}, with smallest band gap obtained with codoped-TiO{sub 2}. The photocatalytic activities for all TiO{sub 2} photocatalysts were tested by 4-chlorophenol (organic pollutant) degradation under visible light irradiation. It was found that codoped TiO{sub 2} exhibits the best photocatalytic activity, which could be attributed to the synergistic effect produced by V and N dopants.

  7. GeO{sub 2}/Ge structure submitted to annealing in deuterium: Incorporation pathways and associated oxide modifications

    SciTech Connect (OSTI)

    Bom, N. M., E-mail: nicolau.bom@ufrgs.br [PGMICRO, UFRGS, 91509-900 Porto Alegre, Rio Grande do Sul (Brazil); Soares, G. V.; Hartmann, S.; Bordin, A. [Instituto de Física, UFRGS, 91509-900 Porto Alegre, Rio Grande do Sul (Brazil); Radtke, C. [Instituto de Química, UFRGS, 91509-900 Porto Alegre, Rio Grande do Sul (Brazil)

    2014-10-06T23:59:59.000Z

    Deuterium (D) incorporation in GeO{sub 2}/Ge structures following D{sub 2} annealing was investigated. Higher D concentrations were obtained for GeO{sub 2}/Ge samples in comparison to their SiO{sub 2}/Si counterparts annealed in the same conditions. Oxygen vacancies produced during the annealing step in D{sub 2} constitute defect sites for D incorporation, analogous to defects at the SiO{sub 2}/Si interfacial region. Besides D incorporation, volatilization of the oxide layer is also observed as a consequence of D{sub 2} annealing, especially in the high temperature regime of the present study (>450?°C). In parallel to this volatilization, the stoichiometry and chemical structure of remnant oxide are modified as well. These results evidence the broader impact of forming gas annealing in dielectric/Ge structures with respect to SiO{sub 2}/Si counterparts.

  8. Alternative current conduction mechanisms of organic-inorganic compound [N(CH{sub 3}){sub 3}H]{sub 2}ZnCl{sub 4}

    SciTech Connect (OSTI)

    Ben Bechir, M., E-mail: mohamedbenbechir@hotmail.fr; Karoui, K.; Guidara, K.; Ben Rhaiem, A. [Laboratory of Condensed Matter, Faculty of Sciences, University of Sfax, BP1171, 3018 Sfax (Tunisia); Tabellout, M. [LUNAM Université, Université du Maine, CNRS UMR 6283, Institut des Molécules et Matériaux du Mans (IMMM), Avenue Olivier Messiaen, F-72085, Le Mans Cedex 09 (France)

    2014-04-21T23:59:59.000Z

    [N(CH{sub 3}){sub 3}H]{sub 2}ZnCl{sub 4} has been studied by X-ray powder diffraction patterns, differential scanning calorimetry (DSC), and impedance spectroscopy. The [N(CH{sub 3}){sub 3}H]{sub 2}ZnCl{sub 4} hybrid compound is crystallized at room temperature (T ? 300?K) in the orthorhombic system with Pnma space group. Five phase transitions (T{sub 1}?=?255?K, T{sub 2}?=?282?K, T{sub 3}?=?302?K, T{sub 4}?=?320?K, and T{sub 5}?=?346?K) have been proved by DSC measurements. The electrical technique was measured in the 10{sup ?1}-10{sup 7}?Hz frequency range and 233–363?K temperature interval. The frequency dependence of alternative current (AC) conductivity is interpreted in terms of Jonscher's law. The AC electrical conduction in [N(CH{sub 3}){sub 3}H]{sub 2}ZnCl{sub 4} is analyzed by different processes, which can be attributed to several models: the correlated barrier hopping model in phase I, the overlapping large polaron tunneling model in phase II, the quantum mechanical tunneling model in phase IV, and the non-overlapping small polaron tunneling model in phases III, V, and VI. The conduction mechanism is studied with the help of Elliot's theory, and the Elliot's parameters are determined.

  9. Alternative current conduction mechanisms of organic-inorganic compound [N(CH{sub 3}){sub 3}H]{sub 2}CuCl{sub 4}

    SciTech Connect (OSTI)

    Ben Bechir, M., E-mail: mohamedbenbechir@hotmail.fr; Karoui, K.; Guidara, K.; Ben Rhaiem, A. [Laboratory of Condensed Matter, Faculty of Sciences, University of Sfax, BP1171, 3018 Sfax (Tunisia); Tabellout, M. [LUNAM Université, Université du Maine, CNRS UMR 6283, Institut des Molécules et Matériaux du Mans (IMMM), Avenue Olivier Messiaen, F-72085 Le Mans Cedex 09 (France)

    2014-05-28T23:59:59.000Z

    The [N(CH{sub 3}){sub 3}H]{sub 2}CuCl{sub 4} single crystal has been analyzed by X-ray powder diffraction patterns, differential scanning calorimetry (DSC), and electrical impedance spectroscopy. [N(CH{sub 3}){sub 3}H]{sub 2}CuCl{sub 4} crystallizes at room temperature in the monoclinic system with P2{sub 1}/{sub C} space group. Three phase transitions at T{sub 1}?=?226?K, T{sub 2}?=?264?K, and T{sub 3}?=?297?K have been evidenced by DSC measurements. The electrical technique was measured in the 10{sup ?1}–10{sup 7}?Hz frequency range and 203–313?K temperature intervals. The frequency dependence of alternative current (AC) conductivity is interpreted in terms of Jonscher's law (developed). The AC electrical conduction in [N(CH{sub 3}){sub 3}H]{sub 2}CuCl{sub 4} compound is studied by two processes which can be attributed to a hopping transport mechanism: the correlated barrier hopping model in phases I, II, and III, the non-overlapping small polaron tunneling model in phase IV. The conduction mechanism is interpreted with the help of Elliot's theory, and the Elliot's parameters are found.

  10. Preparation of magnetic Fe{sub 3}O{sub 4}/SiO{sub 2}/Bi{sub 2}WO{sub 6} microspheres and their application in photocatalysis

    SciTech Connect (OSTI)

    Chen, Su-Hua; Yin, Zhen [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China)] [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Luo, Sheng-Lian, E-mail: sllou@hnu.edu.cn [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China)] [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Au, Chak-Tong [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China) [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China); Li, Xue-Jun [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China)] [Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China)

    2013-02-15T23:59:59.000Z

    Graphical abstract: Display Omitted Highlights: ? We described the preparation and characterization of the Fe{sub 3}O{sub 4}/SiO{sub 2}/Bi{sub 2}WO{sub 6} magnetic microspheres composites. ? The photocatalytic activities of the composites were also investigated. ? With the combination of photocatalysts and Fe{sub 3}O{sub 4}/SiO{sub 2}, good stability and magnetic separability can be achieved. ? And to the best of our knowledge, this is the first report concerning Bi{sub 2}WO{sub 6} nanoparticles loaded on Fe{sub 3}O{sub 4}/SiO{sub 2} particles. -- Abstract: Magnetic Fe{sub 3}O{sub 4}/SiO{sub 2}/Bi{sub 2}WO{sub 6} microspheres with photocatalytic properties have been synthesized using a silica layer for “bonding” (adhering Bi{sub 2}WO{sub 6} to Fe{sub 3}O{sub 4}). The morphology, composition and magnetic properties of the Fe{sub 3}O{sub 4}/SiO{sub 2}/Bi{sub 2}WO{sub 6} composites were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, vibrating sample magnetometry, and BET surface area analysis. The activity of the material in photocatalytic decoloration of aqueous rhodamine B (RhB) solution under visible light was evaluated. The results showed that Bi{sub 2}WO{sub 6} combined well with the magnetic Fe{sub 3}O{sub 4}/SiO{sub 2} nanoparticles. The Fe{sub 3}O{sub 4}/SiO{sub 2}/Bi{sub 2}WO{sub 6} composites were spherical in shape, having a mean size of 2 ?m. The spent catalyst could be recycled with only slight decline in catalytic activity. It is envisaged that the stability, reusability, and magnetic nature of the Fe{sub 3}O{sub 4}/SiO{sub 2}/Bi{sub 2}WO{sub 6} catalyst warrants its application in photocatalysis.

  11. Ionic conductivity and the formation of cubic CaH{sub 2} in the LiBH{sub 4}–Ca(BH{sub 4}){sub 2} composite

    SciTech Connect (OSTI)

    Sveinbjörnsson, Dadi; Blanchard, Didier [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, P.O. Box 49, DK-4000 Roskilde (Denmark); Myrdal, Jon Steinar Gardarsson [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, P.O. Box 49, DK-4000 Roskilde (Denmark); Center for Atomic-Scale Materials Design, Department of Physics, Technical University of Denmark, Anker Engelunds Vej 1, DK-2800 Lyngby (Denmark); Younesi, Reza; Viskinde, Rasmus [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, P.O. Box 49, DK-4000 Roskilde (Denmark); Riktor, Marit Dalseth [Physics Department, Institute for Energy Technology, Instituttveien 18, P.O. Box 40, NO-2027 Kjeller (Norway); Norby, Poul [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, P.O. Box 49, DK-4000 Roskilde (Denmark); Vegge, Tejs, E-mail: teve@dtu.dk [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, P.O. Box 49, DK-4000 Roskilde (Denmark)

    2014-03-15T23:59:59.000Z

    LiBH{sub 4}–Ca(BH{sub 4}){sub 2} composites were prepared by ball milling. Their crystal structures and phase composition were investigated using synchrotron X-ray diffraction and Rietveld refinement, and their ionic conductivity was measured using impedance spectroscopy. The materials were found to form a physical mixture. The composites were composed of ?-Ca(BH{sub 4}){sub 2}, ?-Ca(BH{sub 4}){sub 2} and orthorhombic LiBH{sub 4}, and the relative phase quantities of the Ca(BH{sub 4}){sub 2} polymorphs varied significantly with LiBH{sub 4} content. The formation of small amounts of orthorhombic CaH{sub 2} and cubic CaH{sub 2} in a CaF{sub 2}-like structure was observed upon heat treatment. Concurrent formation of elemental boron may also occur. The ionic conductivity of the composites was measured using impedance spectroscopy, and was found to be lower than that of ball milled LiBH{sub 4}. Electronic band structure calculations indicate that cubic CaH{sub 2} with hydrogen defects is electronically conducting. Its formation along with the possible precipitation of boron therefore has an effect on the measured conductivity of the LiBH{sub 4}–Ca(BH{sub 4}){sub 2} composites and may increase the risk of an internal short-circuit in the cells. -- Graphical abstract: An Arrhenius plot of the ionic conductivity of the LiBH{sub 4}–Ca(BH{sub 4}){sub 2} composites (red, blue, green). The ionic conductivity of ball milled (gray) and non-milled (black) LiBH{sub 4} is shown for comparison. The filled symbols are measured during heating runs and the empty symbols are measured during subsequent cooling runs. The conductivity of the composites is in all cases higher during cooling, most probably due to the formation of an electronically conducting layer containing defect-rich cubic CaH{sub 2}. Such layer formation could eventually lead to a short circuit in the cell and reveals a general issue of chemical stability that should be attended to in the development of solid electrolyte materials. Highlights: • The LiBH{sub 4}–Ca(BH{sub 4}){sub 2} composite forms a physical mixture rather than a solid solution. • The formation of defect-rich, cubic CaH{sub 2} in a CaF{sub 2}-like structure is observed. • A new layer containing cubic CaH{sub 2} is conducting and may lead to a short-circuit.

  12. Mechanical properties of fiber-reinforced YBa{sub 2}Cu{sub 3}O{sub x} and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} bars

    SciTech Connect (OSTI)

    Goretta, K.C.; Martin, L.J.; Singh, D.; Poeppel, R.B.; Chen, Nan; Chu, C.Y.; Routbort, J.C. [Argonne National Lab., IL (United States); Gleixner, R.A. [Babcock and Wilcox Co., Alliance, OH (United States)

    1993-07-01T23:59:59.000Z

    Strength in four-point bending and fracture toughness of YBa{sub 2}Cu{sub 3}O{sub x} (123) and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (2212) were examined at room temperature. The 123 was reinforced with 15 vol.% Y{sub 2}BaCuO{sub 5} (211) fibers and was processed to 90--91% density by cold pressing and sintering. The 2212 was reinforced with 15 vol.% 2212 fibers and was processed to {approx}90% density by sinter forging. The 123/211 composites had a fracture toughness of 1.9 MPa(m){sup 0.5}, which is 20--30% higher than that of corresponding monoliths, but exhibited no improvement in strength. The strength and fracture toughness of the 2212/2212 composites were 102 MPa and 2.7 MPa(m){sup 0.5}, respectively, which were slight improvements over the monoliths. Transport critical current densities at 77 K were only slightly affected by the fiber additions.

  13. Synthesis, crystal structure, spectroscopic and thermal properties of [Et{sub 4}N][Ta{sub 6}Br{sub 12}(H{sub 2}O){sub 6}]Br{sub 4}.4H{sub 2}O (Et=ethyl)-A new compound with the paramagnetic [Ta{sub 6}Br{sub 12}]{sup 3+} cluster core

    SciTech Connect (OSTI)

    Peric, Berislav, E-mail: bperic@irb.h [Ruder Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb (Croatia); Jozic, Drazan [Ruder Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb (Croatia); Planinic, Pavica, E-mail: planinic@irb.h [Ruder Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb (Croatia); Brnicevic, Nevenka [Ruder Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb (Croatia); Giester, Gerald [Institut fuer Mineralogie und Kristallographie, Universitaet Wien-Geozentrum Althanstrasse, 14, 1090 Wien (Austria)

    2009-09-15T23:59:59.000Z

    A new hexanuclear cluster compound, [Et{sub 4}N][Ta{sub 6}Br{sub 12}(H{sub 2}O){sub 6}]Br{sub 4}.4H{sub 2}O (Et=ethyl) (1), with the paramagnetic [Ta{sub 6}Br{sub 12}]{sup 3+} cluster entity, was synthesized and characterized by elemental and TG/DTA analyses, IR and UV/Vis spectroscopy and by a single-crystal X-ray diffraction study. The presence of the paramagnetic [Ta{sub 6}Br{sub 12}]{sup 3+} unit was confirmed also by the room-temperature magnetic and EPR measurements. The compound crystallizes in the tetragonal I4{sub 1}/a space group, with a=14.299(5), c=21.241(5) A, Z=4, R{sub 1}(F)/wR{sub 2}(F{sup 2})=0.0296/0.0811. The structure contains discrete [Ta{sub 6}Br{sub 12}(H{sub 2}O){sub 6}]{sup 3+} cations with an octahedron of metal atoms edge-bridged by bromine atoms and with water molecules occupying all six terminal positions. The cluster units are positioned in the vertices of the three-dimensional (pseudo)diamond lattice. The structure shows similarities with literature reported structures of cluster compounds crystallizing in the diamond (Fd3-barm) space group. - Graphical abstract: Two interpenetrating (pseudo)diamond nets formed by packing of the paramagnetic [Ta{sub 6}Br{sub 12}(H{sub 2}O)]{sup 3+} (octahedral) and diamagnetic [Et{sub 4}N]{sup +} (spheres) cations.

  14. Electronic Phase Separation in Pr sub 1 sub x (Ca, Sr) sub x MnO sub 3 subdelta and Tunneling Magnetoresistance in Sr sub 2 FeMoO sub 6

    E-Print Network [OSTI]

    Niebieskikwiat, D G

    2003-01-01T23:59:59.000Z

    In this work, we approach two aspects of the physics of magnetic perovskites presenting colossal magnetoresistance (CMR). Firstly, we go deeply into the phase separation (PS) between the ferromagnetic (FM) metallic state and the antiferro-magnetic (AFM) charge ordered (CO) insulating state, in manganites of the type Pr sub 1 sub x (Ca,Sr) sub x MnO sub 3 subdelta. Secondly, and more briefly, we analyze the problem of the influence of the grain boundary insulating barriers on the tunneling magnetoresistance in the Sr sub 2 FeMoO sub 6 double perovskite.The use of different measurement techniques allowed us to make a complete characterization of the PS state in the compounds Pr sub 0.65Ca sub 0 sub . sub 3 sub 5 sub - sub y Sr sub y MnO sub 3 for 0 ) keeping constant the carrier concentration (x = 0.35). This material presents an evolution from a CO insulating phase for small (y =0), towards the FM metallic phase for large (y = 0.20). In t

  15. Pressure effects on magnetic pair-breaking in Mn- and Eu-substituted BaFe{sub 2}As{sub 2}

    SciTech Connect (OSTI)

    Rosa, P. F. S., E-mail: ferrari@ifi.unicamp.br [Instituto de Física “Gleb Wataghin,” UNICAMP, Campinas-SP 13083-859 (Brazil); University of California, Irvine, California 92697-4574 (United States); Garitezi, T. M.; Adriano, C.; Urbano, R. R.; Pagliuso, P. G. [Instituto de Física “Gleb Wataghin,” UNICAMP, Campinas-SP 13083-859 (Brazil); Grant, T.; Fisk, Z. [University of California, Irvine, California 92697-4574 (United States); Fernandes, R. M. [School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-05-07T23:59:59.000Z

    We report a combined study of hydrostatic pressure (P ? 25 kbar) and chemical substitution on the magnetic pair-breaking effect in Eu- and Mn-substituted BaFe{sub 2}As{sub 2} single crystals. At ambient pressure, both substitutions suppress the superconducting (SC) transition temperature (T{sub c}) of BaFe{sub 2–x}Co{sub x}As{sub 2} samples slightly under the optimally doped region, indicating the presence of a pair-breaking effect. At low pressures, an increase of T{sub c} is observed for all studied compounds followed by an expected decrease at higher pressures. However, in the Eu dilute system, T{sub c} further increases at higher pressure along with a narrowing of the SC transition, suggesting that a pair-breaking mechanism reminiscent of the Eu Kondo single impurity regime is being suppressed by pressure. Furthermore, Electron Spin Resonance (ESR) measurements indicate the presence of Mn{sup 2+} and Eu{sup 2+} local moments and the microscopic parameters extracted from the ESR analysis reveal that the Abrikosov–Gor'kov expression for magnetic pair-breaking in a conventional sign-preserving superconducting state cannot describe the observed reduction of T{sub c}.

  16. Processing & properties La{sub 1-x}A{sub x}Co{sub 1-y}Fe{sub y}O{sub 3}(A = Sr, Ca) perovskites

    SciTech Connect (OSTI)

    Stevenson, J.W.; Armstrong, T.R.; Pederson, L.R. [and others

    1995-04-01T23:59:59.000Z

    Selected compositions within the system La{sub 1-x}A{sub x}Co{sub 1-y}Fe{sub y}O{sub 3-{delta}}(A = Sr, Ca) were prepared by combustion synthesis and characterized by XRD, TGA, electrical conductivity, and oxygen permeation measurements. Substantial weight loss (due to loss of lattice oxygen) was observed in some compositions at high temperatures. For Sr containing materials, this weight loss increased with increasing Sr content. A substantial decrease in electronic conductivity was observed at high temperatures in Sr doped materials; this decrease was related to the decreased oxygen stoichiometry at these temperatures. In Sr doped compositions, oxygen flux increased with increasing Sr content. Calculated values of ionic conductivity were greater than the conductivity of yttria stabilized zirconia. Substitution of Ca for Sr resulted in substantially lower fluxes.

  17. Observation of ?<sub>c1sub> Decays into Vector Meson Pairs ??, ?? and, ??

    SciTech Connect (OSTI)

    Ablikim, M.; Achasov, M. N.; An, L.; An, Q.; An, Z. H.; Bai, J. Z.; Baldini, R.; Ban, Y.; Becker, J.; Berger, N.; Bertani, M.; Bian, J. M.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Cao, G. F.; Cao, X. X.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, Y.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denysenko, I.; Destefanis, M.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Duan, M. Y.; Fan, R. R.; Fang, J.; Fang, S. S.; Feng, C. Q.; Fu, C. D.; Fu, J. L.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Greco, M.; Grishin, S.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y. P.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Heng, Y. K.; Hou, Z. L.; Hu, H. M.; Hu, J. F.; Hu, T.; Huang, B.; Huang, G. M.; Huang, J. S.; Huang, X. T.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, X. B.; Ji, X. L.; Jia, L. K.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kavatsyuk, M.; Komamiya, S.; Kuehn, W.; Lange, J. S.; Leung, J. K. C.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, Lei; Li, N. B.; Li, Q. J.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Liao, X. T.; Liu, B. J.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, C. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, G. C.; Liu, H.; Liu, H. B.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K.; Liu, K. Y.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. H.; Liu, Y. B.; Liu, Y. W.; Liu, Yong; Liu, Z. A.; Liu, Z. Q.; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, T.; Ma, X.; Ma, X. Y.; Maggiora, M.; Malik, Q. A.; Mao, H.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Muchnoi, N. Yu.; Nefedov, Y.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pelizaeus, M.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Pun, C. S. J.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, X. S.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schulze, J.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Sonoda, S.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. D.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tang, X. F.; Tian, H. L.; Toth, D.; Varner, G. S.; Wan, X.; Wang, B. Q.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q.; Wang, S. G.; Wang, X. L.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Wen, Q. G.; Wen, S. P.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, W.; Wu, Z.; Xiao, Z. J.; Xie, Y. G.; Xu, G. F.; Xu, G. M.; Xu, H.; Xu, Y.; Xu, Z. R.; Xu, Z. Z.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, M.; Yang, T.; Yang, Y.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, L.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, L.; Zhang, S. H.; Zhang, T. R.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, Jiawei; Zhao, Jingwei; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, S. J.; Zhao, T. C.; Zhao, X. H.; Zhao, Y. B.; Zhao, Z. G.; Zhao, Z. L.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zheng, Z. P.; Zhong, B.; Zhong, J.; Zhong, L.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, X. W.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.; Zuo, J. X.; Zweber, P.

    2011-08-01T23:59:59.000Z

    Using (106±4)×10? ?(3686) events accumulated with the BESIII detector at the BEPCII e?e? collider, we present the first measurement of decays of ?<sub>c1sub> to vector meson pairs ??, ??, and ??. The branching fractions are measured to be (4.4±0.3±0.5)×10??, (6.0±0.3±0.7)×10??, and (2.2±0.6±0.2)×10??, for ?<sub>c1sub> ???, ??, and ??, respectively, which indicates that the hadron helicity selection rule is significantly violated in ?<sub>cJ> decays. In addition, the measurement of ?<sub>cJ>??? provides the first indication of the rate of doubly OZI-suppressed ?<sub>cJ> decay. Finally, we present improved measurements for the branching fractions of ?<sub>c0sub> and ?<sub>c2sub> to vector meson pairs.

  18. High-performance, 0.6-eV, Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} thermophotovoltaic converters and monolithically interconnected modules

    SciTech Connect (OSTI)

    Wanlass, M.W.; Carapella, J.J.; Duda, A.; Emery, K.; Gedvilas, L.; Moriarty, T.; Ward, S.; Webb, J.D.; Wu, X. [National Renewable Energy Laboratory (NREL), 1617 Cole Blvd., Golden, Colorado, 80401 (United States); Murray, C.S. [Bettis Atomic Power Laboratory, P.O. Box 79/ZAP08D, West Mifflin, Pennsylvania, 15122 (United States)

    1999-03-01T23:59:59.000Z

    Recent progress in the development of high-performance, 0.6-eV Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} thermophotovoltaic (TPV) converters and monolithically interconnected modules (MIMs) is described. The converter structure design is based on using a lattice-matched InAs{sub 0.32}P{sub 0.68}/Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} double-heterostructure (DH) device, which is grown lattice-mismatched on an InP substrate, with an intervening compositionally step-graded region of InAs{sub y}P{sub 1{minus}y}. The Ga{sub 0.32}In{sub 0.68}As alloy has a room-temperature band gap of {approximately}0.6 eV and contains a p/n junction. The InAs{sub 0.32}P{sub 0.68} layers have a room-temperature band gap of {approximately}0.96 eV and serve as passivation/confinement layers for the Ga{sub 0.32}In{sub 0.68}As p/n junction. InAs{sub y}P{sub 1{minus}y} step grades have yielded DH converters with superior electronic quality and performance characteristics. Details of the microstructure of the converters are presented. Converters prepared for this work were grown by atmospheric-pressure metalorganic vapor-phase epitaxy (APMOVPE) and were processed using a combination of photolithography, wet-chemical etching, and conventional metal and insulator deposition techniques. Excellent performance characteristics have been demonstrated for the 0.6-eV TPV converters. Additionally, the implementation of MIM technology in these converters has been highly successful. {copyright} {ital 1999 American Institute of Physics.}

  19. Silicon etch using SF{sub 6}/C{sub 4}F{sub 8}/Ar gas mixtures

    SciTech Connect (OSTI)

    Bates, Robert L., E-mail: rlb043000@utdallas.edu [University of Texas at Dallas, Natural Science and Engineering Laboratory (NSERL), Rm. 3.422, P.O. Box 830688, Richardson, Texas 75083 (United States); Stephan Thamban, P. L. [Department of Mechanical Engineering, University of Texas Dallas, Natural Science and Engineering Laboratory (NSERL), P.O. Box 830688, Richardson, Texas 75083 (United States); Goeckner, Matthew J. [Department of Mathematics, University of Texas Dallas, Natural Science and Engineering Laboratory (NSERL), Rm. 3.408, P.O. Box 830688, Mailstop FO35, Richardson, Texas 75083 (United States); Overzet, Lawrence J. [Department of Electrical Engineering, University of Texas Dallas, Natural Science and Engineering Laboratory (NSERL), Rm. 3.404, P.O. Box 830688, Mailstop RH10, Richardson, Texas 75083 (United States)

    2014-07-01T23:59:59.000Z

    While plasmas using mixtures of SF{sub 6}, C{sub 4}F{sub 8}, and Ar are widely used in deep silicon etching, very few studies have linked the discharge parameters to etching results. The authors form such linkages in this report. The authors measured the optical emission intensities of lines from Ar, F, S, SF{sub x}, CF{sub 2}, C{sub 2}, C{sub 3}, and CS as a function of the percentage C{sub 4}F{sub 8} in the gas flow, the total gas flow rate, and the bias power. In addition, the ion current density and electron temperature were measured using a floating Langmuir probe. For comparison, trenches were etched of various widths and the trench profiles (etch depth, undercut) were measured. The addition of C{sub 4}F{sub 8} to an SF{sub 6}/Ar plasma acts to reduce the availability of F as well as increase the deposition of passivation film. Sulfur combines with carbon in the plasma efficiently to create a large optical emission of CS and suppress optical emissions from C{sub 2} and C{sub 3}. At low fractional flows of C{sub 4}F{sub 8}, the etch process appears to be controlled by the ion flux more so than by the F density. At large C{sub 4}F{sub 8} fractional flows, the etch process appears to be controlled more by the F density than by the ion flux or deposition rate of passivation film. CF{sub 2} and C{sub 2} do not appear to cause deposition from the plasma, but CS and other carbon containing molecules as well as ions do.

  20. A novel technique for measurement of thermal rate constants and temperature dependences of dissociative recombination: CO{sub 2}{sup +}, CF{sub 3}{sup +}, N{sub 2}O{sup +}, C{sub 7}H{sub 8}{sup +}, C{sub 7}H{sub 7}{sup +}, C{sub 6}H{sub 6}{sup +}, C{sub 6}H{sub 5}{sup +}, C{sub 5}H{sub 6}{sup +}, C{sub 4}H{sub 4}{sup +}, and C{sub 3}H{sub 3}{sup +}

    SciTech Connect (OSTI)

    Fournier, Joseph A.; Shuman, Nicholas S.; Melko, Joshua J.; Ard, Shaun G.; Viggiano, Albert A. [Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico 87117 (United States)

    2013-04-21T23:59:59.000Z

    A novel technique using a flowing afterglow-Langmuir probe apparatus for measurement of temperature dependences of rate constants for dissociative recombination (DR) is presented. Low ({approx}10{sup 11} cm{sup -3}) concentrations of a neutral precursor are added to a noble gas/electron afterglow plasma thermalized at 300-500 K. Charge exchange yields one or many cation species, each of which may undergo DR. Relative ion concentrations are monitored at a fixed reaction time while the initial plasma density is varied between 10{sup 9} and 10{sup 10} cm{sup -3}. Modeling of the decrease in concentration of each cation relative to the non-recombining noble gas cation yields the rate constant for DR. The technique is applied to several species (O{sub 2}{sup +}, CO{sub 2}{sup +}, CF{sub 3}{sup +}, N{sub 2}O{sup +}) with previously determined 300 K values, showing excellent agreement. The measurements of those species are extended to 500 K, with good agreement to literature values where they exist. Measurements are also made for a range of C{sub n}H{sub m}{sup +} (C{sub 7}H{sub 7}{sup +}, C{sub 7}H{sub 8}{sup +}, C{sub 5}H{sub 6}{sup +}, C{sub 4}H{sub 4}{sup +}, C{sub 6}H{sub 5}{sup +}, C{sub 3}H{sub 3}{sup +}, and C{sub 6}H{sub 6}{sup +}) derived from benzene and toluene neutral precursors. C{sub n}H{sub m}{sup +} DR rate constants vary from 8-12 Multiplication-Sign 10{sup -7} cm{sup 3} s{sup -1} at 300 K with temperature dependences of approximately T{sup -0.7}. Where prior measurements exist these results are in agreement, with the exception of C{sub 3}H{sub 3}{sup +} where the present results disagree with a previously reported flat temperature dependence.

  1. Putative quantum criticality in the (Cr{sub 90}Ir{sub 10}){sub 100?y}V{sub y} alloy system

    SciTech Connect (OSTI)

    Fernando, P. R.; Prinsloo, A. R. E., E-mail: alettap@uj.ac.za; Sheppard, C. J. [Department of Physics, University of Johannesburg, PO Box 524, Auckland Park 2006 (South Africa); Lodya, L. [Sasol Technology, Research and Development, 1 Klasie Havenga Road, Sasolburg 1947 (South Africa)

    2014-05-07T23:59:59.000Z

    Quantum criticality (QC) in spin-density-wave antiferromagnetic Cr and Cr alloy systems is a topic of current interest. In the present study, V was used as a tuning parameter to drive the Néel transition temperature (T{sub N}) of the (Cr{sub 90}Ir{sub 10}){sub 100?y}V{sub y} alloy series with 0???y???14.3 to zero and search for effects of QC in the process. The magnetic properties and possible QC behaviour (QCB) in this alloy system were investigated through electrical resistivity (?), specific heat (C{sub p}), and susceptibility (?) measurements as a function of temperature (T), indicating that T{sub N} is suppressed to zero at a critical concentration y{sub c}???9. The Sommerfeld coefficient (?) is considered a key indicator of QCB and a peak is observed in ?(y) at y{sub c} on decreasing y through this concentration, followed by a sharp decreasing trend. This behaviour is reminiscent of that observed for ? of the prototypical Cr{sub 100?x}V{sub x} QC system and allows for the classification of y{sub c} in the (Cr{sub 90}Ir{sub 10}){sub 100?y}V{sub y} alloy system as a possible QC point.

  2. Single-crystal structure of vanadium-doped La{sub 2}Mo{sub 2}O{sub 9}

    SciTech Connect (OSTI)

    Alekseeva, O. A., E-mail: olalex@ns.crys.ras.ru; Antipin, A. M. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Gagor, A.; Pietraszko, A. [Polish Academy of Sciences, Trzebiatowski Institute of Low Temperature and Structure Research (Poland)] [Polish Academy of Sciences, Trzebiatowski Institute of Low Temperature and Structure Research (Poland); Novikova, N. E.; Sorokina, N. I. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Kharitonova, E. P.; Voronkova, V. I. [Moscow State University (Russian Federation)] [Moscow State University (Russian Federation)

    2013-11-15T23:59:59.000Z

    A high-precision X-ray diffraction study of single crystals of two compositions-La{sub 2}Mo{sub 1.78}V{sub 0.22}O{sub 8.89} and La{sub 2}Mo{sub 1.64}V{sub 0.36}O{sub 8.82}-was performed. In the vanadium-doped compounds, as in the structure of the metastable {beta}{sub ms} phase of pure La{sub 2}Mo{sub 2}O{sub 9}, the La and Mo atoms and one of the three oxygen atoms are displaced from the threefold axis, on which they are located in the high-temperature {beta} phase. The structure contains two partially occupied oxygen sites. It was shown that molybdenum atoms are partially replaced by vanadium atoms, which are not involved in the disordering, are located on the threefold axis, and are shifted toward one of the oxygen atoms. This is consistent with the temperature-induced changes in the structure of La{sub 2}Mo{sub 2}O{sub 9} and the changes in the properties of these crystals caused by the introduction of vanadium atoms into the structure.

  3. New simple A{sub 4} neutrino model for nonzero {theta}{sub 13} and large {delta}{sub CP}

    SciTech Connect (OSTI)

    Ishimori, Hajime [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)

    2013-05-23T23:59:59.000Z

    In a new simple application of the non-Abelian discrete symmetry A{sub 4} to charged-lepton and neutrino mass matrices, we show that for the current experimental central value of sin{sup 2} 2{theta}{sub 13} Asymptotically-Equal-To 0.1, leptonic CP violation is necessarily large, i.e. Double-Vertical-Line tan{delta}{sub CP} Double-Vertical-Line > 1.3. We also consider T{sub 7} model with one parameter to be complex, thus allowing for one Dirac CP phase {delta}{sub CP} and two Majorana CP phases {alpha}{sub 1,2}. We find a slight modification to this correlation as a function of {delta}{sub CP}. For a given set of input values of {Delta}m{sup 2}{sub 21}, {Delta}m{sup 2}{sub 32}, {theta}{sub 12}, and {theta}{sub 13}, we obtain sin{sup 2} 2{theta}{sub 23} and m{sub ee} (the effective Majorana neutrino mass in neutrinoless double beta decay) as functions of tan {delta}{sub CP}. We find that the structure of this model always yields small Double-Vertical-Line tan {delta}{sub CP} Double-Vertical-Line .

  4. Measurement of p/sub arrow-up/+p/sub arrow-up/. -->. p+p with a 16. 5-GeV/c polarized proton beam

    SciTech Connect (OSTI)

    Brown, K.A.; Bruni, R.J.; Cameron, P.R.; Crabb, D.G.; Cummings, R.L.; Khiari, F.Z.; Krisch, A.D.; Lin, A.M.T.; Raymond, R.S.; Roser, T.; Terwilliger, K.M.; Danby, G.T.; Ratner, L.G.; Peaslee, D.C.; O'Fallon, J.R.; Roberts, J.B.; Bhatia, T.S.; Northcliffe, L.C.; Simonius, M.

    1985-06-01T23:59:59.000Z

    Using the new Brookhaven Alternating Gradient Synchrotron polarized proton beam and our polarized proton target, we measured the spin-spin correlation parameter A/sub n/n in 16.5-GeV/c proton-proton elastic scattering. We found an A/sub n/n of (6.1 +- 3.0)% at P/sub perpendicular/ /sup 2/ = 2.2 (GeV/c)/sup 2/. We also measured the analyzing power A in two independent ways, providing a good test of possible experimental errors. Comparing our new data with 12-GeV Argonne Zero Gradient Synchrotron data shows no evidence for strong energy dependence in A/sub n/n in this medium-P/sub perpendicular/ /sup 2/ region.

  5. Hysteretic electrical transport in BaTiO{sub 3}/Ba{sub 1?x}Sr{sub x}TiO{sub 3}/Ge heterostructures

    SciTech Connect (OSTI)

    Ngai, J. H.; Kumah, D. P.; Walker, F. J. [Department of Applied Physics and Center for Research on Interface Structures and Phenomena, Yale University, 15 Prospect Street, New Haven, Connecticut 06520-8284 (United States); Ahn, C. H. [Department of Applied Physics and Center for Research on Interface Structures and Phenomena, Yale University, 15 Prospect Street, New Haven, Connecticut 06520-8284 (United States); Department of Mechanical Engineering and Materials Science, Yale University, 10 Hillhouse Avenue, New Haven, Connecticut 06520-8267 (United States)

    2014-02-10T23:59:59.000Z

    We present electrical transport measurements of heterostructures comprised of BaTiO{sub 3} and Ba{sub 1?x}Sr{sub x}TiO{sub 3} epitaxially grown on Ge. Sr alloying imparts compressive strain to the BaTiO{sub 3}, which enables the thermal expansion mismatch between BaTiO{sub 3} and Ge to be overcome to achieve c-axis oriented growth. The conduction bands of BaTiO{sub 3} and Ba{sub 1?x}Sr{sub x}TiO{sub 3} are nearly aligned with the conduction band of Ge, which facilitates electron transport. Electrical transport measurements through the dielectric stack exhibit rectifying behavior and hysteresis, where the latter is consistent with ferroelectric switching.

  6. Synthesis, structure and chemical bonding of CaFe{sub 2?x}Rh{sub x}Si{sub 2} (x=0, 1.32, and 2) and SrCo{sub 2}Si{sub 2}

    SciTech Connect (OSTI)

    Hlukhyy, Viktor, E-mail: viktor.hlukhyy@lrz.tu-muenchen.de; Hoffmann, Andrea V.; Fässler, Thomas F.

    2013-07-15T23:59:59.000Z

    The finding of superconductivity in Ba{sub 0.6}K{sub 0.4}Fe{sub 2}As{sub 2} put the attention on the investigation of compounds that crystallize with ThCr{sub 2}Si{sub 2} structure type such as AT{sub 2}X{sub 2} (A=alkali/alkaline earth/rare earth element; T=transition metal and X=element of the 13–15th group). In this context the silicides CaFe{sub 2}Si{sub 2}, CaFe{sub 0.68(6)}Rh{sub 1.32(6)}Si{sub 2}, CaRh{sub 2}Si{sub 2} and SrCo{sub 2}Si{sub 2} have been synthesized by reaction of the elements under an argon atmosphere. Single crystals were obtained by special heat treatment in welded niobium/tantalum ampoules. The compounds were investigated by means of powder and single crystal X-ray diffraction. All compounds crystallize in the ThCr{sub 2}Si{sub 2}-type structure with space group I4/mmm (No. 139): a=3.939(1) Å, c=10.185(1) Å, R{sub 1}=0.045, 85 F{sup 2} values, 8 variable parameters for CaFe{sub 2}Si{sub 2}; a=4.0590(2) Å, c=9.9390(8) Å, R{sub 1}=0.030, 90 F{sup 2} values, 10 variable parameters for CaFe{sub 0.68(6)}Rh{sub 1.32(6)}Si{sub 2}; a=4.0695(1) Å, c=9.9841(3) Å, R{sub 1}=0.031, 114 F{sup 2} values, 9 variable parameters for CaRh{sub 2}Si{sub 2}; and a=3.974(1) Å, c=10.395(1) Å, R{sub 1}=0.036, 95 F{sup 2} values, 8 variable parameters for SrCo{sub 2}Si{sub 2}. The structure of SrCo{sub 2}Si{sub 2} contains isolated [Co{sub 2}Si{sub 2}]{sup 2?} 2D-layers in the ab-plane whereas in CaFe{sub 2?x}Rh{sub x}Si{sub 2} the [T{sub 2}Si{sub 2}] layers (T=Fe and Rh) are interconnected along the c-axis via Si3Si bonds resulting in a three-dimentional (3D) [T{sub 2}Si{sub 2}]{sup 2?} polyanions and therefore belong to the so-called collapsed form of the ThCr{sub 2}Si{sub 2}-type structure. The SrCo{sub 2}Si{sub 2} and CaRh{sub 2}Si{sub 2} are isoelectronic to the parent 122 iron–pnictide superconductors AeFe{sub 2}As{sub 2} (Ae=alkaline earth elements), whereas CaFe{sub 2}Si{sub 2} is a full substituted variant (As/Si) of CaFe{sub 2}As{sub 2}. The crystal chemistry and chemical bonding in the title compounds are discussed in terms of LMTO band structure calculations and a topological analysis using the Electron Localization Function (ELF). - Graphical abstract: The SrCo{sub 2}Si{sub 2} and CaFe{sub 2?x}Rh{sub x}Si{sub 2} (x==0, 1.32, and 2) crystallize in the ThCr{sub 2}Si{sub 2}-type. The structure of SrCo{sub 2}Si{sub 2} contains isolated [Co{sub 2}Si{sub 2}]{sup 2?} layers in the ab-plane, whereas the [T{sub 2}Si{sub 2}] layers in CaFe{sub 2?x}Rh{sub x}Si{sub 2} are interconnected along the c-axis via Si3Si bonds resulting in a [T{sub 2}Si{sub 2}]{sup 2?} network. - Highlights: • Synthesis and structure of ternary silicides SrCo{sub 2}Si{sub 2} and CaFe{sub 2?x}Rh{sub x}Si{sub 2} (x=0, 1.32, and 2). • The SrCo{sub 2}Si{sub 2} and CaRh{sub 2}Si{sub 2} are isoelectronic to the parent 122 iron–pnictide superconductors AeFe{sub 2}As{sub 2}. • CaFe{sub 2}Si{sub 2} is a full substituted variant (As/Si) of superconductor CaFe{sub 2}As{sub 2}. • The title compounds demonstrate the tunable Si3Si distances.

  7. Dynamics of the reaction of C{sub 3}(a{sup 3}?{sub u}) radicals with C{sub 2}H{sub 2}: A new source for the formation of C{sub 5}H

    SciTech Connect (OSTI)

    Huang, Wen-Jian; Sun, Yi-Lun; Chin, Chih-Hao; Lee, Shih-Huang, E-mail: shlee@nsrrc.org.tw [National Synchrotron Radiation Research Center (NSRRC), 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan (China)

    2014-09-28T23:59:59.000Z

    The reaction C{sub 3}(a{sup 3}?{sub u}) + C{sub 2}H{sub 2} ? C{sub 5}H + H was investigated at collision energy 10.9 kcal mol{sup ?1} that is less than the enthalpy of ground-state reaction C{sub 3}(X{sup 1}?{sub g}{sup +}) + C{sub 2}H{sub 2} ? C{sub 5}H + H. C{sub 3}(a{sup 3}?{sub u}) radicals were synthesized from 1% C{sub 4}F{sub 6}/He by pulsed high-voltage discharge. The title reaction was conducted in a crossed molecular-beam apparatus equipped with a quadrupole-mass filter. Product C{sub 5}H was interrogated with time-of-flight spectroscopy and synchrotron vacuum-ultraviolet ionization. Reactant C{sub 3}(a{sup 3}?{sub u}) and product C{sub 5}H were identified using photoionization spectroscopy. The ionization thresholds of C{sub 3}(X{sup 1}?{sub g}{sup +}) and C{sub 3}(a{sup 3}?{sub u}) are determined as 11.6 ± 0.2 eV and 10.0 ± 0.2 eV, respectively. The C{sub 5}H product is identified as linear pentynylidyne that has an ionization energy 8.4 ± 0.2 eV. The title reaction releases translational energy 10.6 kcal mol{sup ?1} in average and has an isotropic product angular distribution. The quantum-chemical calculation indicates that the C{sub 3}(a{sup 3}?{sub u}) radical attacks one of the carbon atoms of C{sub 2}H{sub 2} and subsequently a hydrogen atom is ejected to form C{sub 5}H + H, in good agreement with the experimental observation. As far as we are aware, the C{sub 3}(a{sup 3}?{sub u}) + C{sub 2}H{sub 2} reaction is investigated for the first time. This work gives an implication for the formation of C{sub 5}H from the C{sub 3}(a{sup 3}?{sub u}) + C{sub 2}H{sub 2} reaction occurring in a combustion or discharge process of C{sub 2}H{sub 2}.

  8. Yb{sub 5}Ni{sub 4}Sn{sub 10} and Yb{sub 7}Ni{sub 4}Sn{sub 13}: New polar intermetallics with 3D framework structures

    SciTech Connect (OSTI)

    Lei Xiaowu; Sun Zhongming; Li Longhua [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Zhong Guohua; Hu Chunli [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China); Mao Jianggao, E-mail: mjg@fjirsm.ac.c [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 (China)

    2010-04-15T23:59:59.000Z

    The title compounds have been obtained by solid state reactions of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction studies. Yb{sub 5}Ni{sub 4}Sn{sub 10} adopts the Sc{sub 5}Co{sub 4}Si{sub 10} structure type and crystallizes in the tetragonal space group P4/mbm (No. 127) with cell parameters of a=13.785(4) A, c=4.492 (2) A, V=853.7(5) A{sup 3}, and Z=2. Yb{sub 7}Ni{sub 4}Sn{sub 13} is isostructural with Yb{sub 7}Co{sub 4}InGe{sub 12} and crystallizes in the tetragonal space group P4/m (No. 83) with cell parameters of a=11.1429(6) A, c=4.5318(4) A, V=562.69(7) A{sup 3}, and Z=1. Both structures feature three-dimensional (3D) frameworks based on three different types of one-dimensional (1D) channels, which are occupied by the Yb atoms. Electronic structure calculations based on density functional theory (DFT) indicate that both compounds are metallic. These results are in agreement with those from temperature-dependent resistivity and magnetic susceptibility measurements. - Graphical abstract: Two new ytterbium nickel stannides, namely, Yb{sub 5}Ni{sub 4}Sn{sub 10} and Yb{sub 7}Ni{sub 4}Sn{sub 13}, have been synthesized and structurally characterized by single-crystal X-ray diffraction studies. Both their structures feature three-dimensional (3D) frameworks based on three different types of one-dimensional (1D) channels, which are situated by all the Yb atoms. Electronic structure calculations based on density functional theory (DFT) indicate that both compounds are metallic, which are in accordance with the results from temperature-dependent resistivity and magnetic susceptibility measurements.

  9. Hydrogen demand, production, and cost by region to 2050.

    SciTech Connect (OSTI)

    Singh, M.; Moore, J.; Shadis, W.; Energy Systems; TA Engineering, Inc.

    2005-10-31T23:59:59.000Z

    This report presents an analysis of potential hydrogen (H{sub 2}) demand, production, and cost by region to 2050. The analysis was conducted to (1) address the Energy Information Administration's (EIA's) request for regional H{sub 2} cost estimates that will be input to its energy modeling system and (2) identify key regional issues associated with the use of H{sub 2} that need further study. Hydrogen costs may vary substantially by region. Many feedstocks may be used to produce H{sub 2}, and the use of these feedstocks is likely to vary by region. For the same feedstock, regional variation exists in capital and energy costs. Furthermore, delivery costs are likely to vary by region: some regions are more rural than others, and so delivery costs will be higher. However, to date, efforts to comprehensively and consistently estimate future H{sub 2} costs have not yet assessed regional variation in these costs. To develop the regional cost estimates and identify regional issues requiring further study, we developed a H{sub 2} demand scenario (called 'Go Your Own Way' [GYOW]) that reflects fuel cell vehicle (FCV) market success to 2050 and allocated H{sub 2} demand by region and within regions by metropolitan versus non-metropolitan areas. Because we lacked regional resource supply curves to develop our H{sub 2} production estimates, we instead developed regional H{sub 2} production estimates by feedstock by (1) evaluating region-specific resource availability for centralized production of H{sub 2} and (2) estimating the amount of FCV travel in the nonmetropolitan areas of each region that might need to be served by distributed production of H{sub 2}. Using a comprehensive H{sub 2} cost analysis developed by SFA Pacific, Inc., as a starting point, we then developed cost estimates for each H{sub 2} production and delivery method by region and over time (SFA Pacific, Inc. 2002). We assumed technological improvements over time to 2050 and regional variation in energy and capital costs. Although we estimate substantial reductions in H{sub 2} costs over time, our cost estimates are generally higher than the cost goals of the U.S. Department of Energy's (DOE's) hydrogen program. The result of our analysis, in particular, demonstrates that there may be substantial variation in H{sub 2} costs between regions: as much as $2.04/gallon gasoline equivalent (GGE) by the time FCVs make up one-half of all light-vehicle sales in the GYOW scenario (2035-2040) and $1.85/GGE by 2050 (excluding Alaska). Given the assumptions we have made, our analysis also shows that there could be as much as a $4.82/GGE difference in H{sub 2} cost between metropolitan and non-metropolitan areas by 2050 (national average). Our national average cost estimate by 2050 is $3.68/GGE, but the average H{sub 2} cost in metropolitan areas in that year is $2.55/GGE and that in non-metropolitan areas is $7.37/GGE. For these estimates, we assume that the use of natural gas to produce H{sub 2} is phased out. This phase-out reflects the desire of DOE's Office of Hydrogen, Fuel Cells and Infrastructure Technologies (OHFCIT) to eliminate reliance on natural gas for H{sub 2} production. We conducted a sensitivity run in which we allowed natural gas to continue to be used through 2050 for distributed production of H{sub 2} to see what effect changing that assumption had on costs. In effect, natural gas is used for 66% of all distributed production of H{sub 2} in this run. The national average cost is reduced to $3.10/GGE, and the cost in non-metropolitan areas is reduced from $7.37/GGE to $4.90, thereby reducing the difference between metropolitan and non-metropolitan areas to $2.35/GGE. Although the cost difference is reduced, it is still substantial. Regional differences are similarly reduced, but they also remain substantial. We also conducted a sensitivity run in which we cut in half our estimate of the cost of distributed production of H{sub 2} from electrolysis (our highest-cost production method). In this run, our national average cost estimate is reduced even further, to

  10. Flux creep and critcal-current anisotropy in Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8+//sub delta/

    SciTech Connect (OSTI)

    Biggs, B.D.; Kunchur, M.N.; Lin, J.J.; Poon, S.J.; Askew, T.R.; Flippen, R.B.; Subramanian, M.A.; Gopalakrishnan, J.; Sleight, A.W.

    1989-04-01T23:59:59.000Z

    We have studied magnetic relaxation, temperature dependence of the critical currents, magnetic irreversibility, and lower critical fields in single crystals of the high-T/sub c/ superconductor Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8+//sub delta/ (idealized composition) through magnetization measurements. The results are analyzed within the framework of the critical state and a thermally activated flux-creep model. The results indicate three different critical curents and flux-creep rates depending on the relative orientation of the current, the field, and the Cu-O planes. The flux-creep rate for flux lines moving perpendicular to the planes, was found to be unobservably low. Similarly, the critical current density perpendicular to the planes was very low. However the critical current density in the plane and the flux-pinning well depth U/sub 0/, for fluxon motion parallel to the planes, are similar to the values found in Y-Ba-Cu-O. Implications of insulating layers between the Cu-O planes are discussed.

  11. New hypodiphosphates of the alkali metals: Synthesis, crystal structure and vibrational spectra of the hypodiphosphates(IV) M{sub 2}[(H{sub 2}P{sub 2}O{sub 6})(H{sub 4}P{sub 2}O{sub 6})] (M=Rb and Cs)

    SciTech Connect (OSTI)

    Wu, Peng [Institut fuer Anorganische und Analytische Chemie der TU Clausthal, Paul-Ernst-Strasse 4, D-38678 Clausthal-Zellerfeld (Germany)] [Institut fuer Anorganische und Analytische Chemie der TU Clausthal, Paul-Ernst-Strasse 4, D-38678 Clausthal-Zellerfeld (Germany); Wiegand, Thomas; Eckert, Hellmut [Institut fuer Physikalische Chemie and Graduate School of Chemistry, Westfaelische Wilhelms-Universitaet Muenster, Corrensstr. 28/30, D-48149 Muenster (Germany)] [Institut fuer Physikalische Chemie and Graduate School of Chemistry, Westfaelische Wilhelms-Universitaet Muenster, Corrensstr. 28/30, D-48149 Muenster (Germany); Gjikaj, Mimoza, E-mail: mimoza.gjikaj@tu-clausthal.de [Institut fuer Anorganische und Analytische Chemie der TU Clausthal, Paul-Ernst-Strasse 4, D-38678 Clausthal-Zellerfeld (Germany)] [Institut fuer Anorganische und Analytische Chemie der TU Clausthal, Paul-Ernst-Strasse 4, D-38678 Clausthal-Zellerfeld (Germany)

    2012-10-15T23:59:59.000Z

    The new hypodiphosphates(IV) Rb{sub 2}[(H{sub 2}P{sub 2}O{sub 6})(H{sub 4}P{sub 2}O{sub 6})] (1) and Cs{sub 2}[(H{sub 2}P{sub 2}O{sub 6})(H{sub 4}P{sub 2}O{sub 6})] (2) were synthesized by soft chemistry reactions from aqueous solutions of hypophosphoric acid and the corresponding heavy alkali-metal carbonates. Their crystal structures were determined by single crystal X-ray diffraction. Both compounds crystallize isotypic in the triclinic space group P-1 with one formula unit in the unit cell. The structures are built up by discrete (H{sub 2}P{sub 2}O{sub 6}){sup 2-} and (H{sub 4}P{sub 2}O{sub 6}) units in staggered conformation for the P{sub 2}O{sub 6} skeleton and the corresponding alkali-metal cations. In the (H{sub 2}P{sub 2}O{sub 6}){sup 2-} ion the hydrogen atoms are in a 'trans-trans' conformation. O{center_dot}H-O hydrogen bonds between the (H{sub 2}P{sub 2}O{sub 6}){sup 2-} and (H{sub 4}P{sub 2}O{sub 6}) groups consolidate the structures into a three-dimensional network. The FT-Raman and {sup 31}P and {sup 1}H and MAS NMR spectra of the title compounds have been recorded and interpreted, especially with respect to their assignment to the (H{sub 2}P{sub 2}O{sub 6}){sup 2-} and (H{sub 4}P{sub 2}O{sub 6}) groups. Thermogravimetric data of 2 have been interpreted in terms of a thermal decomposition model. - Graphical Abstract: The layered compounds Rb{sub 2}[(H{sub 2}P{sub 2}O{sub 6})(H{sub 4}P{sub 2}O{sub 6})] and Cs{sub 2}[(H{sub 2}P{sub 2}O{sub 6})(H{sub 4}P{sub 2}O{sub 6})] have been synthesized and investigated. Both crystallize isotypic. The structures are built up by discrete (H{sub 2}P{sub 2}O{sub 6}){sup 2-} and (H{sub 4}P{sub 2}O{sub 6}) units and the corresponding alkali-metal cations. Highlights: Black-Right-Pointing-Pointer Synthesis and single-crystal structure of new alkali hypodiphosphates. Black-Right-Pointing-Pointer Structures are characterized by [(H{sub 2}P{sub 2}O{sub 6})(H{sub 4}P{sub 2}O{sub 6})]{sup 2-} units and M{sup +} cations. Black-Right-Pointing-Pointer (H{sub 2}P{sub 2}O{sub 6}){sup 2-} and (H{sub 4}P{sub 2}O{sub 6}) units are linked by short hydrogen bonds. Black-Right-Pointing-Pointer Both compounds are characterized by {sup 31}P MAS-NMR spectra.

  12. Emerging NO sub x /SO sub x control technologies

    SciTech Connect (OSTI)

    Livengood, C.D. (Argonne National Lab., IL (United States)); Markussen, J.M. (USDOE Pittsburgh Energy Technology Center, PA (United States))

    1992-01-01T23:59:59.000Z

    The development of advanced flue-gas-cleanup (FGC) technologies fro the control of sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) emissions continues to be a very active area of research and development, both in this country and abroad. This activity is driven both by legislation (such as the recent revisions to the Clean Air Act) and by the desire to develop technologies that surpass current options in terms of performance, costs, operability, and waste/by-product properties. New issues, such as concern over global climate changes and the health effects of toxic air emissions ( air toxics''), are also helping to shape and prioritize the development programs. This paper provides a status report on a number of integrated FGC systems that have reached a significant stage of development, focusing on post-combustion processes that have been rested or are ready for testing at the pilot scale or larger. While some information that was presented at the 1991 CIBO NO{sub x} IV Control Conference is repeated for the sake of completeness, we have updated each section to reflect the most recent reported developments. Although a wide variety of technologies is discussed, it should be noted that there are a number of other integrated approaches, such as slagging combustors, fluidized-bed combustion, gasification/combined-cycle systems, and various processes combining low-NO{sub x} burners with SO{sub 2}-sorbent injection in the furnace. These other approaches also offer features that should not be overlooked when evaluating alternatives for a specific application.

  13. Regional Summary Pacific Region Management Context

    E-Print Network [OSTI]

    , for the Eastern Pacific Ocean, and the Western and Central Pacific Fishery Commission, for the Western PacificRegional Summary Pacific Region Management Context The Pacific Region includes California, Oregon, and Washington. Federal fisheries in this region are managed by the Pacific Fishery Management Council (PFMC

  14. Directed-energy electron-beam processing of a hypoeutectic Cr/sub 90/Ta/sub 10/ alloy

    SciTech Connect (OSTI)

    Huang, J.S.; Kaufmann, E.N.

    1987-09-01T23:59:59.000Z

    A hypoeutectic Cr/sub 90/Ta/sub 10/ alloy was processed using a directed-energy electron-beam surface melting and resolidification technique to study its microstructure evolution during rapid solidification. The power of the electron beam was 2500 W and the scan speed ranged from 0.13 to 2.0 m/sec. Microstructure characteristics such as transitions from planar front to dendritic growth, and from cellular to dendritic growth were observed. At low solidification rate, the interdendritic regions are characterized by the Cr/Cr/sub 2/Ta eutectic, and at high solidification rate the intercellular regions are characterized by a Cr/sub 2/Ta phase. For the latter, the distribution of Ta-solute across the interior of a cell is very uniform. In a given sample, the primary cell spacing increases as the solidification front moves from the substrate/regrowth interface toward the surface. The solidification parameters, i.e., temperature gradient and growth velocity, were determined with finite-element heat flow analyses. The observed microstructure characteristics were correlated to these parameters using available theoretical models. 9 refs., 11 figs., 1 tab.

  15. Properties measurements of (U{sub 0.7}Pu{sub 0.3})O{sub 2-x} in PO{sub 2}-controlled atmosphere

    SciTech Connect (OSTI)

    Kato, M.; Murakami, T.; Sunaoshi, T. [Advanced Nuclear System Research and Development Directorate, Japan Atomic Energy Agency, Muramatsu Tokai-mura Ibaraki, 319-1194 (Japan); Nelson, A.T.; McClellan, K.J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2013-07-01T23:59:59.000Z

    The investigation of physical properties of uranium and plutonium mixed oxide (MOX) fuels is important for the development of fast reactor fuels. It is well known that MOX is a nonstoichiometric oxide, and the physical properties change drastically with the Oxygen-to-Metal (O/M) ratio. A control technique for O/M ratio was established for measurements of high temperature properties of uranium and plutonium mixed oxide fuels. Sintering behavior, thermal expansion and O/M change of (U{sub 0.7}Pu{sub 0.3})O{sub 2.00} and (U{sub 0.7}Pu{sub 0.3})O{sub 1.99} were investigated in PO{sub 2}-controlled atmosphere which was controlled by H{sub 2}/H{sub 2}O gas system. Sintering behavior changed drastically with O/M ratio, and shrinkage of (U{sub 0.7}Pu{sub 0.3})O{sub 2.00} was faster and more advanced at lower temperatures as compared with (U{sub 0.7}Pu{sub 0.3})O{sub 1.99}. Thermal expansion was observed to be slightly increased with decreasing O/M ratio. (authors)

  16. Quantum paraelectric glass state in SrCu{sub 3}Ti{sub 4}O{sub 12}

    SciTech Connect (OSTI)

    Kumar, Jitender; Choudhary, Ram Janay; Awasthi, A. M., E-mail: amawasthi@csr.res.in [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001 (India)

    2014-06-30T23:59:59.000Z

    Magnetic and dielectric studies of SrCu{sub 3}Ti{sub 4}O{sub 12} carried out over 5–300?K confirm antiferromagnetic (AFM) ordering of Cu-spins at T{sub N}?=?23?K. Dielectric constant ?? measured across 1?Hz-1 MHz signifies quantum paraelectric character, Barrett-fittable almost down to T{sub N}. Competition of athermal fluctuations and the literature-reported magneto-phonon-softening near T{sub N} manifest a quantum paraelectric glass (QPG) state. Emergent AFM-field tunes the otherwise quantum ordering (at absolute-zero) of the dipoles to finite-temperature kinetic glass transition; spectral dispersion of dielectric constant was unambiguously manifested and characterized. Vogel-Fulcher glass-kinetics parameterization sets the almost relaxation-free QPG state in SrCu{sub 3}Ti{sub 4}O{sub 12} apart from an emergent scaling-class, to which typical ferroelectric relaxors belong.

  17. Li{sub 2}Si{sub 3}O{sub 7}: Crystal structure and Raman spectroscopy

    SciTech Connect (OSTI)

    Krueger, Hannes [Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck (Austria)], E-mail: Hannes.Krueger@uibk.ac.at; Kahlenberg, Volker [Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck (Austria); Kaindl, Reinhard [Christian-Doppler-Laboratory for Advanced Hard Coatings at the Institute of Mineralogy and Petrography, University of Innsbruck, 6020 Innsbruck (Austria)

    2007-03-15T23:59:59.000Z

    The crystal structure of metastable Li{sub 2}Si{sub 3}O{sub 7} was determined from single crystal X-ray diffraction data. The orthorhombic crystals were found to adopt space group Pmca with unit cell parameters of a=19.648(3)A, b=5.9969(8)A and c=4.8691(6)A. The content of the cell is Z=4. The obtained structural model was refined to a R-value of 0.035. The structure exhibits silicate sheets, which can be classified as {l_brace}uB,2,1{sub {approx}}{sup 2}{r_brace}[Si{sub 6}O{sub 14}] using the silicate nomenclature of Liebau. The layers are build up from zweier single chains running parallel to c. Raman spectra are presented and compared with other silicates. Furthermore, the structure is discussed versus Na{sub 2}Si{sub 3}O{sub 7}.

  18. Crystal structure, oxidation state and magnetism of Sr{sub x}La{sub 2?x}Cu{sub 0.5}Ru{sub 0.5}O{sub 4} (x=1, 1.5)

    SciTech Connect (OSTI)

    Lü, Minfeng, E-mail: m.f.lv@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Deng, Xiaolong [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Waerenborgh, João C. [IST/ITN, Instituto Superior Técnico, Univ Técnica de Lisboa, CFMC-UL, EN 10, 2686-953 Sacavém (Portugal); Wu, Xiaojie [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Meng, Jian, E-mail: jmeng@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2014-03-15T23:59:59.000Z

    Sr{sub x}La{sub 2?x}Cu{sub 0.5}Ru{sub 0.5}O{sub 4} (x=1, 1.5) oxides with K{sub 2}NiF{sub 4}-type structure were prepared by solid state reaction and characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, magnetic and electrical resistivity measurements. The SrLaCu{sub 0.5}Ru{sub 0.5}O{sub 4} phase was obtained for the first time with a negligible amount of impurities. The octahedral Cu/RuO{sub 6} units are more elongated in SrLaCu{sub 0.5}Ru{sub 0.5}O{sub 4} than in Sr{sub 1.5}La{sub 0.5}Cu{sub 0.5}Ru{sub 0.5}O{sub 4} indicating a greater extent of static Jahn–Teller distortion. XPS suggests that mixed ion pairs Ru{sup 5+}/Ru{sup 4+}?Cu{sup +}/Cu{sup 2+} are present in SrLaCu{sub 0.5}Ru{sub 0.5}O{sub 4}, while Ru remains as Ru{sup 5+} and Cu as Cu{sup 2+} in Sr{sub 1.5}La{sub 0.5}Cu{sub 0.5}Ru{sub 0.5}O{sub 4}. Both samples show spin-glass behavior, which can be explained by competition between ferromagnetic and antiferromagnetic superexchange interactions. The negative Weiss temperature estimated for SrLaCu{sub 0.5}Ru{sub 0.5}O{sub 4}, ?318 K, is significantly lower than ?11.5 K deduced for Sr{sub 1.5}La{sub 0.5}Cu{sub 0.5}Ru{sub 0.5}O{sub 4} which may be related to the higher static Jahn–Teller distortion in the former oxide. -- Graphical abstract: SrLaCu{sub 0.5}Ru{sub 0.5}O{sub 4} with K{sub 2}NiF{sub 4}-type structure show a larger static Jahn–Teller distortion than Sr{sub 1.5}La{sub 0.5}Cu{sub 0.5}Ru{sub 0.5}O{sub 4}, which may be related to stronger antiferromagnetic superexchange interactions. Highlights: • SrLaCu{sub 0.5}Ru{sub 0.5}O{sub 4} (I) larger Jahn–Teller (J–T) distortion than Sr{sub 1.5}La{sub 0.5}Cu{sub 0.5}Ru{sub 0.5}O{sub 4} (II). • Octahedral Cu/RuO{sub 6} units are more elongated in I than in II. • Mixed ion pairs Ru{sup 5+}/Ru{sup 4+}?Cu{sup +}/Cu{sup 2+} are present in I, while Ru remains as Ru{sup 5+} and Cu as Cu{sup 2+} in II. • Negative Weiss temperature of I significantly lower, consistent with higher J–T distortion.

  19. Photochemical removal of NpF sub 6 and PuF sub 6 from UF sub 6 gas streams

    SciTech Connect (OSTI)

    Beitz, J.V.; Williams, C.W.

    1990-01-01T23:59:59.000Z

    A novel photochemical method of removing reactive fluorides from UF{sub 6} gas has been discovered. This method reduces generated waste to little more than the volume of the removed impurities, minimizes loss of UF{sub 6}, and can produce a recyclable by-product, fluorine gas. In our new method, impure UF{sub 6}, is exposed to ultraviolet light which dissociates the UF{sub 6} to UF{sub 5} and fluorine atom. Impurities which chemically react with UF{sub 5} are reduced and form solid compounds easily removed from the gas while UF{sub 5} is converted back to UF{sub 6}. Proof-of-concept testing involved UF{sub 6} containing NpF{sub 6} and PuF{sub 6} with CO added as a fluorine atom scavenger. In a single photolysis step, greater than 5000-fold reduction of PuF{sub 6} was demonstrated while reducing NpF{sub 6} by more than 40-fold. This process is likely to remove corrosion and fission product fluorides that are more reactive than UF{sub 6} and has been demonstrated without an added fluorine atom scavenger by periodically removing photogenerated fluorine gas. 44 refs., 3 figs., 2 tabs.

  20. Scintillator having a MgAI.sub.2O.sub.4 host lattice

    DOE Patents [OSTI]

    Chen, Ching-Fong (Los Alamos, NM)

    2011-12-20T23:59:59.000Z

    A scintillator having a host lattice of MgAl.sub.2O.sub.4 was prepared by hot pressing under a vacuum environment a powder mixture of MgAl.sub.2O.sub.4, CeO.sub.2, and LiF.

  1. Results of the LSND search for {ovr {nu}}{sub {mu}} {yields} {ovr {nu}}{sub e} oscillations

    SciTech Connect (OSTI)

    Federspiel, F.J.

    1996-07-01T23:59:59.000Z

    A search for {ovr {nu}}{sub {mu}}{yields}{ovr {nu}}{sub e} oscillations has been conducted at the Los Alamos Meson Physics Facility by using {ovr {nu}}{sub {mu}} from {mu}{sup +} decay at rest. The {ovr {nu}}{sub e} are detected via the reaction {ovr {nu}}{sub e}p {yields} e{sup +} n , correlated with a {gamma} from np {yields} d{gamma} (2.2 MeV). The use of tight cuts to identify e{sup +} events with correlated {gamma} rays yields 22 events with e{sup +} energy between 36 and 60 MeV and only 4.6 {plus_minus} 0.6 background events. The probability that this observation can be explained by statistical fluctuation is less than 10{sup -7}. Assuming these events are due to oscillations, a likelihood fit to all the e{sup +} events between 20 and 60 MeV has been performed to extract the oscillation parameters sin{sup 2} 2{theta} and {Delta}m{sup 2}. The favored region resulting from this fit is shown.

  2. Synthesis and characterization of (Et/sub 4/N)(M(CO)/sub 5/SR) and (Et/sub 4/N)/sub 2/(M/sub 2/(CO)/sub 8/(SR)/sub 2/) complexes (M = Cr, Mo, W). Ligand substitution reactions and x-ray crystal structure of (Et/sub 4/N)/sub 2/(W/sub 2/(CO)/sub 8/(SPh)/sub 2/)

    SciTech Connect (OSTI)

    Darensbourg, D.J.; Sanchez, K.M.; Reibenspies, J.

    1988-10-05T23:59:59.000Z

    A series of complexes (Et/sub 4/N)(M(CO)/sub 5/SR) (M = Cr, Mo, W; R = H, Ph), have been synthesized and characterized by /sup 1/H and /sup 13/C NMR and ir spectroscopies. Gentle heating causes these complexes to lose a carbonyl ligand, yielding the doubly bridged sulfur dimers M/sub 2/(CO)/sub 8/(..mu..-SR)/sub 2//sup 2 -/. The x-ray crystal structure of (Et/sub 4/N)/sub 2/(W/sub 2/(CO)/sub 8/(SPh)/sub 2/) has been determined. The complex crystallizes in the triclinic space group P /anti 1/ with unit cell parameters a = 9.8664 (17) /angstrom/, b = 9.8566 (22) /angstrom/, c = 11.8270 (26) /angstrom/, ..cap alpha.. = 65.790 (16)/degrees/, ..beta.. = 81.710 (16)/degrees/, ..gamma.. = 82.000 (16)/degrees/, V = 1034.0 (4) /angstrom//sup 3/, and Z = 1. Both mono- and dinuclear metal complexes readily react with phosphorus donor ligands to afford the carbon monoxide substituted complexes cis-M(CO)/sub 4/(P)(SR)/sup -/ (P = PMe/sub 3/, P(OMe)/sub 3/, PPh/sub 3/). In addition, the dimers react with 1 atm of carbon monoxide to re-form the mononuclear species M(CO)/sub 5/SR/sup -/ in quantitative yields. Unsuccessful attempts to insert CO/sub 2/, COS, or CS/sub 2/ into the M-SR bond in the M(CO)/sub 5/SR/sup -/ derivatives are noted. 25 references, 3 figures, 15 tables.

  3. Southwest Regional Partnership on Carbon Sequestration

    SciTech Connect (OSTI)

    Brian McPherson

    2006-03-31T23:59:59.000Z

    The Southwest Partnership on Carbon Sequestration completed its Phase I program in December 2005. The main objective of the Southwest Partnership Phase I project was to evaluate and demonstrate the means for achieving an 18% reduction in carbon intensity by 2012. Many other goals were accomplished on the way to this objective, including (1) analysis of CO{sub 2} storage options in the region, including characterization of storage capacities and transportation options, (2) analysis and summary of CO{sub 2} sources, (3) analysis and summary of CO{sub 2} separation and capture technologies employed in the region, (4) evaluation and ranking of the most appropriate sequestration technologies for capture and storage of CO{sub 2} in the Southwest Region, (5) dissemination of existing regulatory/permitting requirements, and (6) assessing and initiating public knowledge and acceptance of possible sequestration approaches. Results of the Southwest Partnership's Phase I evaluation suggested that the most convenient and practical ''first opportunities'' for sequestration would lie along existing CO{sub 2} pipelines in the region. Action plans for six Phase II validation tests in the region were developed, with a portfolio that includes four geologic pilot tests distributed among Utah, New Mexico, and Texas. The Partnership will also conduct a regional terrestrial sequestration pilot program focusing on improved terrestrial MMV methods and reporting approaches specific for the Southwest region. The sixth and final validation test consists of a local-scale terrestrial pilot involving restoration of riparian lands for sequestration purposes. The validation test will use desalinated waters produced from one of the geologic pilot tests. The Southwest Regional Partnership comprises a large, diverse group of expert organizations and individuals specializing in carbon sequestration science and engineering, as well as public policy and outreach. These partners include 21 state government agencies and universities, five major electric utility companies, seven oil, gas and coal companies, three federal agencies, the Navajo Nation, several NGOs, and the Western Governors Association. This group is continuing its work in the Phase II Validation Program, slated to conclude in 2009.

  4. Insight into cation disorder of Li{sub 2}Fe{sub 0.5}Mn{sub 0.5}SiO{sub 4}

    SciTech Connect (OSTI)

    Bini, Marcella [Dept. of Chemistry, University of Pavia, viale Taramelli 16, Pavia 27100 (Italy); Ferrari, Stefania, E-mail: stefania.ferrari@unipv.it [Dept. of Chemistry, University of Pavia, viale Taramelli 16, Pavia 27100 (Italy); Capsoni, Doretta; Spreafico, Clelia; Tealdi, Cristina; Mustarelli, Piercarlo [Dept. of Chemistry, University of Pavia, viale Taramelli 16, Pavia 27100 (Italy)

    2013-04-15T23:59:59.000Z

    Transition metal lithium orthosilicates are promising cathode materials for lithium-ion batteries. Here we report a combined experimental (in situ X-ray diffraction) and computational (static lattice and molecular dynamics) study of the thermal behavior of the Li{sub 2}Fe{sub 0.5}Mn{sub 0.5}SiO{sub 4} orthosilicate from room temperature to 950 °C. Our X-ray results showed that Pmnb polymorph is the most stable all over the explored temperature range. A significant cation disorder up to 80%, based on the anti-site defect, was found. The defect concentration depends on the synthesis route and temperature, and is completely reversible after the thermal treatments. Moreover, a careful analysis of the impurity phases allowed us to identify Li{sub 2}SiO{sub 3}, Fe{sub 3}O{sub 4} and Li{sub 3}Fe{sub 5}O{sub 8}, the last one never reported before. The minimization of defects by opportunely tuning the synthetic parameters would be of great importance in view of potential applications of these materials in lithium batteries. - Graphical abstract: A combined experimental in situ X-ray diffraction and computational study of the thermal behavior of the Li{sub 2}Fe{sub 0.5}Mn{sub 0.5}SiO{sub 4} is reported herein. The anti-site defect does justify the diffraction patterns changes with temperature. Highlights: ? Study of the thermal behavior of Li{sub 2}Fe{sub 0.5}Mn{sub 0.5}SiO{sub 4}. ? The anti-site defect does justify the diffraction patterns changes with temperature. ? The Pmnb polymorph is stable in the investigated temperaturerange.

  5. HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM

    E-Print Network [OSTI]

    HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM IN PENNSYLVANIA HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM date ­ November 23, 2004 · Contract end date ­ March 31, 2006 #12;Hydrogen Regional Infrastructure Program in Pennsylvania Hydrogen Regional Infrastructure Program in Pennsylvania · Objectives ­ Capture

  6. Reduced dimension rovibrational variational calculations of the S{sub 1} state of C{sub 2}H{sub 2}. I. Methodology and implementation

    SciTech Connect (OSTI)

    Changala, P. Bryan, E-mail: bryan.changala@colorado.edu [Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2014-01-14T23:59:59.000Z

    The bending and torsional degrees of freedom in S{sub 1} acetylene, C{sub 2}H{sub 2}, are subject to strong vibrational resonances and rovibrational interactions, which create complex vibrational polyad structures even at low energy. As the internal energy approaches that of the barrier to cis-trans isomerization, these energy level patterns undergo further large-scale reorganization that cannot be satisfactorily treated by traditional models tied to local minima of the potential energy surface for nuclear motion. Experimental spectra in the region near the cis-trans transition state have revealed these complicated new patterns. In order to understand near-barrier spectroscopic observations and to predict the detailed effects of cis-trans isomerization on the rovibrational energy level structure, we have performed reduced dimension rovibrational variational calculations of the S{sub 1} state. In this paper, we present the methodological details, several of which require special care. Our calculation uses a high accuracy ab initio potential surface and a fully symmetrized extended complete nuclear permutation inversion group theoretical treatment of a multivalued internal coordinate system that is appropriate for large amplitude bending and torsional motions. We also discuss the details of the rovibrational basis functions and their symmetrization, as well as the use of a constrained reduced dimension rovibrational kinetic energy operator.

  7. Radiation Tolerance of A{sub 2}Ti{sub 2}O{sub 7} Materials - A Question of Bonding?

    SciTech Connect (OSTI)

    Whittle, Karl R. [University of Sheffield, Sheffield, S1 3JD (United Kingdom); Lumpkin, Gregory R.; Smith, Katherine L.; Blackford, Mark G. [Australian Nuclear Science and Technology Organisation, Sydney, NSW 2234 (Australia); Harvey, Elizabeth J. [University of Cambridge, Cambridge, CB2 3EQ (United Kingdom); Zaluzec, Nestor J. [Argonne National Laboratory, Chicago, IL, 60439 (United States)

    2007-07-01T23:59:59.000Z

    The resistance of Ln{sub 2}Ti{sub 2}O{sub 7} (Ln = lanthanide) compounds to radiation damage is an important topic in the understanding and development of new materials by which radioactive nuclear waste can safely be immobilised. A model has been developed, from previously published density functional theory and molecular orbital theory simulations of the band structure for Ln{sub 2}Ti{sub 2}O{sub 7} materials. This model provides a chemical interpretation of radiation stability. (authors)

  8. Thermoelectric properties of M{sub 2}Mo{sub 6}Se{sub 6} (M =Tl,In)

    SciTech Connect (OSTI)

    Verebelyi, D.T.; Payne, J.E.; Tessema, G.X.; Mengistu, E.

    1997-07-01T23:59:59.000Z

    The authors have measured the thermal conductivity of Tl{sub 2}Mo{sub 6}Se{sub 6}, a quasi-one dimensional conductor which belongs to the family of M{sub 2}Mo{sub 6}X{sub 6} linear chain compounds. Using these results and the measurements of the Seebeck coefficient and the electrical conductivity the authors estimate the dimensionless figure of merit to be of the order of 0.08. This result suggest that this compound and other related compounds are good potential TE.

  9. Micro-Raman spectroscopic study of nanolaminated Ti{sub 5}Al{sub 2}C{sub 3}

    SciTech Connect (OSTI)

    Zhang, H.; Li, Z. J. [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Wang, X. H. [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); Xiang, H. M.; Zhou, Y. C, E-mail: yczhou714@gmail.com [Science and Technology of Advanced Functional Composite Laboratory, ARIMPT, No.1 South Dahongmen Road, Beijing 100076 (China)

    2014-03-31T23:59:59.000Z

    Micro-Raman spectroscopic study and lattice dynamics calculations were conducted to study a recently identified layered ternary carbide, Ti{sub 5}Al{sub 2}C{sub 3}. The experimental Raman shifts were remarkably consistent with the calculated values. Polarized Raman spectrum was collected in the polycrystalline sample, which confirmed the theoretical symmetry assignment of the Raman modes. In addition, the atomic vibrations of the peaks at 192?cm{sup ?1}, 311?cm{sup ?1}, and 660?cm{sup ?1} were identified to be the combination of the counterparts in Ti{sub 2}AlC and Ti{sub 3}AlC{sub 2}.

  10. Multiple temperature-induced magnetization reversals in SmCr{sub 1?x}Fe{sub x}O{sub 3} system

    SciTech Connect (OSTI)

    Yin, L.H.; Liu, Y.; Tan, S.G.; Zhao, B.C.; Dai, J.M. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Song, W.H., E-mail: whsong@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Sun, Y.P., E-mail: ypsun@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China)

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • Multiple temperature-induced magnetization reversals were observed in x = 0.1. • Coexistence of normal and inverse magnetocaloric effects was observed. • A reasonable model was proposed to explain the magnetization reversals. - Abstract: The structural and magnetic properties of the SmCr{sub 1?x}Fe{sub x}O{sub 3} (0 ? x ? 0.5) system have been investigated. Multiple temperature-induced magnetization reversals were observed in x = 0.1. The high-temperature magnetization reversal is due to the special spin structure, in which the net canted moment of the Cr-rich regions and the net moment of the Fe–Cr ordered regions orient in opposite direction; while the low temperature one can be ascribed to the spin reorientation. The sample with x = 0.5 exhibits the highest compensation temperature. Coexistence of normal and inverse magnetocaloric effects was observed in all doped samples. Potential applications in magnetic refrigeration based constant temperature bath near room temperature (?286 K) have been demonstrated.

  11. THE CHEMISTRY OF HO{sub 2}NO{sub 2} AND THE PHOTOCHEMISTRY OF THE HO{sub X}-NO{sub X}-CO{sub X} SYSTEM

    SciTech Connect (OSTI)

    Littlejohn, David

    1980-08-01T23:59:59.000Z

    The objectives of this work were: (1) to investigate formation and destruction reactions of peroxynitric acid, HO{sub 2}NO{sub 2} and (2) to study the photochemistry and kinetics of the HO{sub x} - NO{sub x} - CO{sub x} system were also studied. Investigations were done using infrared spectroscopy to observe the behavior of species involved with the reactions of interest. Several techniques were used, including expansion of reactants into an evacuated cell, static cell decays under constant illumination, and periodic photolysis of flow systems, Infrared absorption cross sections were obtained for CO, CO{sub 2}, NO, NO{sub 2}, N{sub 2}O{sub 5}, HNO{sub 3}, H{sub 2}O{sub 2}, and H{sub 2}O. The spectroscopic measurements were used to derive kinetic information on the systems under study,

  12. Thickness dependence of magnetoelectric response for composites of Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} films on CoFe{sub 2}O{sub 4} ceramic substrates

    SciTech Connect (OSTI)

    Wang, Jing, E-mail: wang-jing@nuaa.edu.cn; Zhu, Kongjun [State Key Laboratory of Mechanics and Control of Mechanical Structures, College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Wu, Xia; Deng, Chaoyong [School of Electronics and Information Engineering, Guizhou University, Guiyang 550025 (China); Peng, Renci; Wang, Jianjun [School of Materials Science and Engineering, and State Key Lab of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China)

    2014-08-15T23:59:59.000Z

    Using chemical solution spin-coating we grew Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} films of different thicknesses on highly dense CoFe{sub 2}O{sub 4} ceramics. X-ray diffraction revealed no other phases except Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} and CoFe{sub 2}O{sub 4}. In many of these samples we observed typical ferroelectric hysteresis loops, butterfly-shaped piezoelectric strains, and the magnetic-field-dependent magnetostriction. These behaviors caused appreciable magnetoelectric responses based on magnetic-mechanical-electric coupling. Our results indicated that the thickness of the Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} film was important in obtaining strong magnetoelectric coupling.

  13. Low temperature and magnetic field behaviour of the (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy

    SciTech Connect (OSTI)

    Jacobs, B. S., E-mail: sjacobs@uj.ac.za; Sheppard, C. J.; Prinsloo, A. R. E. [Department of Physics, University of Johannesburg, P.O. Box 524, Auckland Park 2006 (South Africa); Lodya, L. [Sasol Technology, Research and Development, 1 Klasie Havenga Road, Sasolburg 1947 (South Africa)

    2014-05-07T23:59:59.000Z

    Measurements of the temperature (T) dependence of the magnetic susceptibility (?) and electrical resistance (R) on an antiferromagnetic (AFM) (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy are reported in order to probe the existence of quantum critical behaviour (QCB) utilizing static magnetic fields (H) as a tuning parameter. The results indicate that an increase in H suppresses T{sub N} in such a way that it varies exponentially with increasing H. R(T) measurements show evidence of possible superconducting (SC) behaviour below 1?K at H?=?0?T. These results therefore indicate the coexistence of the AFM and SC phases in the (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy.

  14. Synthesis and structural characterization of the ternary Zintl phases AE{sub 3}Al{sub 2}Pn{sub 4} and AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As)

    SciTech Connect (OSTI)

    He, Hua; Tyson, Chauntae; Saito, Maia [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States); Bobev, Svilen, E-mail: bobev@udel.edu [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States)

    2012-04-15T23:59:59.000Z

    Ten new ternary phosphides and arsenides with empirical formulae AE{sub 3}Al{sub 2}Pn{sub 4} and AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As) have been synthesized using molten Ga, Al, and Pb fluxes. They have been structurally characterized by single-crystal and powder X-ray diffraction to form with two different structures-Ca{sub 3}Al{sub 2}P{sub 4}, Sr{sub 3}Al{sub 2}As{sub 4}, Eu{sub 3}Al{sub 2}P{sub 4}, Eu{sub 3}Al{sub 2}As{sub 4}, Ca{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}As{sub 4}, and Eu{sub 3}Ga{sub 2}As{sub 4} crystallize with the Ca{sub 3}Al{sub 2}As{sub 4} structure type (space group C2/c, Z=4); Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt the Na{sub 3}Fe{sub 2}S{sub 4} structure type (space group Pnma, Z=4). The polyanions in both structures are made up of TrPn{sub 4} tetrahedra, which share common corners and edges to form {sup 2}{sub {infinity}}[TrPn{sub 2}]{sub 3-} layers in the phases with the Ca{sub 3}Al{sub 2}As{sub 4} structure, and {sup 1}{sub {infinity}}[TrPn{sub 2}]{sub 3-} chains in Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} with the Na{sub 3}Fe{sub 2}S{sub 4} structure type. The valence electron count for all of these compounds follows the Zintl-Klemm rules. Electronic band structure calculations confirm them to be semiconductors. - Graphical abstract: AE{sub 3}Al{sub 2}Pn{sub 4} and AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As) crystallize in two different structures-Ca{sub 3}Al{sub 2}P{sub 4}, Sr{sub 3}Al{sub 2}As{sub 4}, Eu{sub 3}Al{sub 2}P{sub 4}, Eu{sub 3}Al{sub 2}As{sub 4}, Ca{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}As{sub 4}, and Eu{sub 3}Ga{sub 2}As{sub 4}, are isotypic with the previously reported Ca{sub 3}Al{sub 2}As{sub 4} (space group C2/c (No. 15)), while Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt a different structure known for Na{sub 3}Fe{sub 2}S{sub 4} (space group Pnma (No. 62). The polyanions in both structures are made up of TrPn{sub 4} tetrahedra, which by sharing common corners and edges, form {sup 2}{sub {infinity}}[TrPn{sub 2}]{sub 3-}layers in the former and {sup 1}{sub {infinity}}[TrPn{sub 2}]{sub 3-} chains in Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4}. Highlights: Black-Right-Pointing-Pointer AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As) are new ternary pnictides. Black-Right-Pointing-Pointer Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt the Na{sub 3}Fe{sub 2}S{sub 4} structure type. Black-Right-Pointing-Pointer The Sr- and Ca-compounds crystallize with the Ca{sub 3}Al{sub 2}As{sub 4} structure type. Black-Right-Pointing-Pointer The valence electron count for all title compounds follows the Zintl-Klemm rules.

  15. Structural characterization of the perovskite series Sr{sub 1?x}La{sub x}Ti{sub 0.5}Mn{sub 0.5}O{sub 3}

    SciTech Connect (OSTI)

    Qasim, Ilyas [School of Chemistry, The University of Sydney, Sydney, NSW 2006 (Australia); Kennedy, Brendan J., E-mail: B.Kennedy@chem.usyd.edu.au [School of Chemistry, The University of Sydney, Sydney, NSW 2006 (Australia)

    2013-04-15T23:59:59.000Z

    The perovskite-type compounds Sr{sub 1?x}La{sub x}Ti{sub 0.5}Mn{sub 0.5}O{sub 3}, x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 have been synthesized by solid-state methods, and their room temperature structures determined using X-ray synchrotron powder diffraction. The x=0.0 end member, SrMn{sub 0.5}Ti{sub 0.5}O{sub 3} is cubic in space group Pm3{sup ¯}m; there being no evidence for ordering of the Ti{sup 4+} and Mn{sup 4+} cations. We find that x=0.5 compound is rhombohedral in R3{sup ¯}c rather than orthorhombic as reported previously. Magnetic measurements suggest that both SrMn{sub 0.5}Ti{sub 0.5}O{sub 3} and Sr{sub 0.5}La{sub 0.5}Mn{sub 0.5}Ti{sub 0.5}O{sub 3} are spin-glasses. - Graphical abstract: A cubic–rhombohedral phase-transition is observed cation disordered perovskites Sr{sub 1?x}La{sub x}Ti{sub 0.5}Mn{sub 0.5}O{sub 3}. Both end members are spin-glasses. Highlights: ? Structural studies of Sr{sub 1?x}La{sub x}Ti{sub 0.5}Nb{sub 0.5}O{sub 3} perovskites, show lack of long range Mn:Ti order. ? Magnetic properties indicative of spin-glass behavior. ? Changes of crystal structure from cubic to rhombohedral with increasing lanthanum content.

  16. Photoluminescence in the Ca{sub x}Sr{sub 1-x}WO{sub 4} system at room temperature

    SciTech Connect (OSTI)

    Porto, S.L. [Laboratorio de Combustiveis e Materiais (LACOM/DQ/CCEN), Universidade Federal da Paraiba, Campus I, Cidade Universitaria, Joao Pessoa, PB, CEP 58059-900 (Brazil); Longo, E. [CMDMC/LIEC, Instituto de Quimica, UNESP-Araraquara, Rua Prof. Francisco Degni s/n, Araraquara, SP, CEP 14800-900 (Brazil); Pizani, P.S.; Boschi, T.M. [Departamento de Fisica, Universidade Federal de Sao Carlos, Sao Carlos, Rodovia Washington Luiz km 235, SP, CEP 13565-905 (Brazil); Simoes, L.G.P. [Centro Multidisciplinar de Desenvolvimento de Materiais Ceramicos (LIEC/DQ), Universidade Federal de Sao Carlos, Rodovia Washington Luiz km 235, Sao Carlos, SP, CEP 13565-905 (Brazil); Lima, S.J.G. [Laboratorio de Solidificacao Rapida, Departamento de Tecnologia Mecanica (LSR/DTM/CT), Universidade Federal da Paraiba, Campus I, Cidade Universitaria, Joao Pessoa, PB, CEP 58059-900 (Brazil); Ferreira, J.M. [Laboratorio de Combustiveis e Materiais (LACOM/DQ/CCEN), Universidade Federal da Paraiba, Campus I, Cidade Universitaria, Joao Pessoa, PB, CEP 58059-900 (Brazil); COAMA, Area de Meio Ambiente, Centro Federal de Educacao Tecnologica da Paraiba, Av. 1o de Maio 720, Jaguaribe, Joao Pessoa, PB, CEP 58015-430 (Brazil); Soledade, L.E.B.; Espinoza, J.W.M.; Cassia-Santos, M.R.; Maurera, M.A.M.A. [Laboratorio de Combustiveis e Materiais (LACOM/DQ/CCEN), Universidade Federal da Paraiba, Campus I, Cidade Universitaria, Joao Pessoa, PB, CEP 58059-900 (Brazil); Paskocimas, C.A. [Departamento de Engenharia Mecanica, Universidade Federal do Rio Grande do Norte, Natal, RN, CEP 59072-970 (Brazil); Santos, I.M.G. [Laboratorio de Combustiveis e Materiais (LACOM/DQ/CCEN), Universidade Federal da Paraiba, Campus I, Cidade Universitaria, Joao Pessoa, PB, CEP 58059-900 (Brazil)], E-mail: ieda@quimica.ufpb.br; Souza, A.G. [Laboratorio de Combustiveis e Materiais (LACOM/DQ/CCEN), Universidade Federal da Paraiba, Campus I, Cidade Universitaria, Joao Pessoa, PB, CEP 58059-900 (Brazil)

    2008-08-15T23:59:59.000Z

    In this work, a study was undertaken about the structural and photoluminescent properties, at room temperature, of powder samples from the Ca{sub x}Sr{sub 1-x}WO{sub 4} (x=0-1.0) system, synthesized by a soft chemical method and heat treated between 400 and 700 deg. C. The material was characterized using Infrared, UV-vis and Raman spectroscopy and XRD. The most intense PL emission was obtained for the sample calcined at 600 deg. C, which is neither highly disordered (400-500 deg. C), nor completely ordered (700 deg. C). Corroborating the role of disorder in the PL phenomenon, the most intense PL response was not observed for pure CaWO{sub 4} or SrWO{sub 4}, but for Ca{sub 0.6}Sr{sub 0.4}WO{sub 4}. The PL emission spectra could be separated into two Gaussian curves. The lower wavelength peak is placed around 530 nm, and the higher wavelength peak at about 690 nm. Similar results were reported in the literature for both CaWO{sub 4} and SrWO{sub 4}. - Graphical abstract: The structural and room temperature photoluminescence of Ca{sub x}Sr{sub 1-x}WO4 synthesized by a soft chemical method was studied. The most intense PL emission was obtained for the sample calcined at 600 deg. C, that is neither highly disordered (400-500 deg. C), nor completely ordered (700 deg. C). Corroborating the role of disorder in the PL phenomenon, the most intense PL response was not observed for pure CaWO{sub 4} or SrWO{sub 4}, but for Ca{sub 0.6}Sr{sub 0.4}WO{sub 4}.

  17. Observation of ?<sub>cJ> decaying into the pp?K?K? final state

    SciTech Connect (OSTI)

    Ablikim, M.; Achasov, M. N.; Alberto, D.; An, L.; An, Q.; An, Z. H.; Bai, J. Z.; Baldini, R.; Ban, Y.; Becker, J.; Berger, N.; Bertani, M.; Bian, J. M.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Cao, G. F.; Cao, X. X.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, Y.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denysenko, I.; Destefanis, M.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fan, R. R.; Fang, J.; Fang, S. S.; Feng, C. Q.; Fu, C. D.; Fu, J. L.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Greco, M.; Grishin, S.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y. P.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Heng, Y. K.; Hou, Z. L.; Hu, H. M.; Hu, J. F.; Hu, T.; Huang, B.; Huang, G. M.; Huang, J. S.; Huang, X. T.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, X. B.; Ji, X. L.; Jia, L. K.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Komamiya, S.; Kuehn, W.; Lange, J. S.; Leung, J. K. C.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, Lei; Li, N. B.; Li, Q. J.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Liao, X. T.; Liu, B. J.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, C. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, G. C.; Liu, H.; Liu, H. B.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K.; Liu, K. Y.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. H.; Liu, Y. B.; Liu, Y. W.; Liu, Yong; Liu, Z. A.; Liu, Z. Q.; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, T.; Ma, X.; Ma, X. Y.; Maggiora, M.; Malik, Q. A.; Mao, H.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Muchnoi, N. Yu.; Nefedov, Y.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pelizaeus, M.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Pun, C. S. J.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, X. S.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schulze, J.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Sonoda, S.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. D.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tang, X. F.; Tian, H. L.; Toth, D.; Varner, G. S.; Wan, X.; Wang, B. Q.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q.; Wang, S. G.; Wang, X. L.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Wen, Q. G.; Wen, S. P.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, W.; Wu, Z.; Xiao, Z. J.; Xie, Y. G.; Xu, G. F.; Xu, G. M.; Xu, H.; Xu, Y.; Xu, Z. R.; Xu, Z. Z.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, M.; Yang, T.; Yang, Y.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, L.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, L.; Zhang, S. H.; Zhang, T. R.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, Jiawei; Zhao, Jingwei; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, S. J.; Zhao, T. C.; Zhao, X. H.; Zhao, Y. B.; Zhao, Z. G.; Zhao, Z. L.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zheng, Z. P.; Zhong, B.; Zhong, J.; Zhong, L.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, X. W.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.; Zuo, J. X.; Zweber, P.

    2011-06-01T23:59:59.000Z

    First measurements of the decays of the three ?<sub>cJ> states to pp?K?K? final states are presented. Intermediate ??K?K? and ?(1520)?pK? resonance states are observed, and branching fractions for ?<sub>cJ>?p?K??(1520), ?(1520)?¯¯¯(1520), and ?pp? are reported. We also measure branching fractions for direct ?<sub>cJ>?pp?K?K? decays. These are first observations of ?<sub>cJ> decays to unstable baryon resonances and provide useful information about the ?<sub>cJ> states. The experiment uses samples of ?<sub>cJ> mesons produced via radiative transitions from 106×10? ?' mesons collected in the BESIII detector at the BEPCII e?e? collider.

  18. Three-dimensional topological insulators Bi{sub 2}Te{sub 3}, Bi{sub 2}Se{sub 3}, and Bi{sub 2}Te{sub 2}Se - a microwave spectroscopy study

    SciTech Connect (OSTI)

    Wolos, A. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland and Faculty of Physics, University of Warsaw, ul Hoza 69, 00-681 Warsaw (Poland); Drabinska, A.; Szyszko, S.; Kaminska, M. [Faculty of Physics, University of Warsaw, ul Hoza 69, 00-681 Warsaw (Poland); Strzelecka, S. G.; Hruban, A.; Materna, A.; Piersa, M. [Institute of Electronic Materials Technology, ul. Wolczynska 133, 01-919 Warsaw (Poland)

    2013-12-04T23:59:59.000Z

    We present results of investigations of three-dimensional topological insulators from a family of bismuth compounds performed in electron spin resonance spectrometer. Next to the standard spin resonance spectra in Bi{sub 2}Se{sub 3} originating from bulk conduction electrons (g{sub Verbar;} = 27.5 ± 0.1 and g{sub ?} = 19.5 ± 0.1), we observed also cyclotron resonance due to topological surface states in Bi{sub 2}Te{sub 3} and non-resonant signal related to weak anti-localization in Bi{sub 2}Te{sub 2}Se. The analysis of the cyclotron resonance signal yields low Fermi velocity equal to 3250 m/s in Bi{sub 2}Te{sub 3}. The phase coherence length determined from weak anti-localization signal equals to 550 nm at low temperatures in Bi{sub 2}Te{sub 2}Se. Relation of the signals to bulk, topological surface or two-dimensional quantum well states is discussed and where possible indicated.

  19. Infrared-optical spectroscopy of transparent conducting perovskite (La,Ba)SnO{sub 3} thin films

    SciTech Connect (OSTI)

    Seo, Dongmin; Yu, Kwangnam; Jun Chang, Young; Choi, E. J., E-mail: echoi@uos.ac.kr [Department of Physics, University of Seoul, Seoul 130-743 (Korea, Republic of); Sohn, Egon; Hoon Kim, Kee [Center for Novel States of Complex Materials Research, Department of Physics and Astronomy, Seoul National University, Seoul 151-747 (Korea, Republic of)

    2014-01-13T23:59:59.000Z

    We have performed optical transmission, reflection, spectroscopic ellipsometry, and Hall effect measurements on the electron-doped La{sub x}Ba{sub 1–x}SnO{sub 3} (x?=?0.04) transparent thin films. From the infrared Drude response and plasma frequency analysis we determine the effective mass of the conducting electron m*?=?0.35m{sub 0}. In the visible-UV region the optical band gap shifts to high energy in (La,Ba)SnO{sub 3} by 0.18?eV compared with undoped BaSnO{sub 3} which, in the context of the Burstein-Moss analysis, is consistent with the infrared-m*. m* of BaSnO{sub 3} is compared with other existing transparent conducting oxides (TCO), and implication on search for high-mobility TCO compounds is discussed.

  20. Morphology of silver on YBa sub 2 Cu sub 3 O sub 7 minus. delta. thin films

    SciTech Connect (OSTI)

    Roshko, A.; Ono, R.H.; Beall, J.A.; Moreland, J. (National Inst. of Standards and Technology, Boulder, CO (US)); Nelson, A.J.; Asher, S.E. (Solar Energy Research Inst., Golden, CO (United States))

    1991-03-01T23:59:59.000Z

    This paper examines the morphology of silver layers deposited and annealed on laser ablated YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} films. Silver was found to dewet the YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (001) surface on annealing in oxygen and nitrogen. This dewetting behavior may be kinetically inhibited by using either thick silver layers or short anneals and low temperatures. Silver layers 70 nm to 2.5 {mu}m thick were studied on films deposited on SrTiO{sub 3}, LaAlO{sub 3} and MgO substrates. Anneal times were varied from 6.5 min to 15 hrs at temperatures from 200 to 700{degrees}C.

  1. Giant magnetocaloric effect in magnetoelectric Eu{sub 1-x}Ba{sub x}TiO{sub 3}

    SciTech Connect (OSTI)

    Rubi, Km; Kumar, Pawan; Maheswar Repaka, D. V.; Chen, Ruofan; Wang, Jian-Sheng; Mahendiran, R., E-mail: phyrm@nus.edu.sg [Department of Physics, 2 Science Drive 3, Faculty of Science, National University of Singapore, Singapore 117551 (Singapore)

    2014-01-20T23:59:59.000Z

    We report the magnetic entropy change (?S{sub m}) in magnetoelectric Eu{sub 1-x}Ba{sub x}TiO{sub 3} for 0.1???x???0.9. We find ??S{sub m}?=?11 (40) J/kg·K in x?=?0.1 for a field change of 1 (5) T, respectively, which is the largest value among all Eu-based oxides. ?S{sub m} arises from the field-induced suppression of the spin entropy of Eu{sup 2+}:4f{sup 7} localized moments. While ???S{sub m}? decreases with increasing x, ???S{sub m}??=?6.58?J/kg·K observed in the high spin diluted composition x?=?0.9 is larger than that in many manganites. Our results indicate that these magnetoelectrics are potential candidates for cryogenic magnetic refrigeration.

  2. CAN H{sub 2}CCC BE THE CARRIER OF BROAD DIFFUSE BANDS?

    SciTech Connect (OSTI)

    Krelowski, J. [Center for Astronomy, Nicholas Copernicus University, Gagarina 11, Pl-87-100 Torun (Poland); Galazutdinov, G. [Instituto de Astronomia, Universidad Catolica del Norte, Av. Angamos 0610, Antofagasta (Chile); Kolos, R., E-mail: jacek@astri.uni.torun.pl, E-mail: runizag@gmail.com, E-mail: robert.kolos@ichf.edu.pl [Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw (Poland)

    2011-07-10T23:59:59.000Z

    The recent assignment of two broad diffuse interstellar bands (DIBs) near 4882 and 5450 A to the propadienylidene (l-C{sub 3}H{sub 2}) molecule is examined using a statistically meaningful sample of targets. Our spectra clearly show that the strength ratio of two broad DIBs is strongly variable, contrary to what should be observed if both features are due to l-C{sub 3}H{sub 2}, since the proposed transitions are lifetime broadened and start from the same level. Moreover, even in directions where the 4882 DIB and 5450 DIB are strong, the third expected l-C{sub 3}H{sub 2} band, in the 5165-5185 A region, is absent. Another puzzling characteristic of l-C{sub 3}H{sub 2} as the proposed carrier of both broad diffuse bands is its column density of several 10{sup 14} cm{sup -2}, inferred from the equivalent width of the 5450 DIB. This value is one order of magnitude higher than N(CH) toward the same objects and two to three orders of magnitude higher than N(H{sub 2}CCC), measured at radio frequencies in absorption, for comparable samples of the diffuse medium. We conclude that the proposed identification of broad DIBs is unjustified.

  3. Polar nanoregions and dielectric properties in high-strain lead-free 0.93(Bi{sub 1/2}Na{sub 1/2})TiO{sub 3}-0.07BaTiO{sub 3} piezoelectric single crystals

    SciTech Connect (OSTI)

    Chen, Cheng-Sao, E-mail: rickchen@cc.hwh.edu.tw [Department of Mechanical Engineering, Hwa-Hsia Institute of Technology, New Taipei City 23567, Taiwan (China); Chen, Pin-Yi [Department of Mechanical Engineering, Ming-Chi University of Technology, New Taipei City 24301, Taiwan (China); Tu, Chi-Shun [Graduate Institute of Applied Science and Engineering, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China)

    2014-01-07T23:59:59.000Z

    A structural coexistence of rhombohedral (R) and tetragonal (T) phases has been revealed in the (001){sub c}-cut lead-free 0.93(Bi{sub 1/2}Na{sub 1/2})TiO{sub 3}–0.07BaTiO{sub 3} (BNB7T) piezoelectric crystals, which grown by the self-flux method, in the lower temperatures by high-resolution synchrotron X-ray diffraction, reciprocal space mapping, and transmission electron microscopy. The dielectric permittivity exhibits a thermal hysteresis in the region of 120–260?°C, implying a first-order-like phase transition from R+T to T. The real part (??) of dielectric permittivity begins to deviates from the Curie-Weiss equation, ???=?C/(T ? T{sub o}), from the Burns temperature T{sub B}?=?460?°C, below which the polar nanoregions (or nanoclusters) develop and attenuate dielectric responses. The polar nanoregions of 5–10?nm were revealed by high-resolution transmission electron microscope. The normal piezoelectric coefficient d{sub 33} exhibits a rapid increase at E?=?15–20?kV/cm and reaches a maximum of d{sub 33} ?450 pC/N. The high piezoelectric response and E-field induced strain in BNB7T single crystals can be attributed to structural phase transitions under an E-field application.

  4. Dispersion states and acid properties of SiO{sub 2}-supported Nb{sub 2}O{sub 5}

    SciTech Connect (OSTI)

    He, Jie, E-mail: jhe@aust.edu.cn [School of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001 (China); Li, Qing-Jie [School of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001 (China); Fan, Yi-Ning [Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China)

    2013-06-15T23:59:59.000Z

    Nb{sub 2}O{sub 5}/SiO{sub 2} samples were prepared by the incipient-wetness impregnation method using niobium oxalate aqueous solution. The microstructure and dispersion process of the niobia species supported on SiO{sub 2} were characterized by means of power X-ray diffraction (XRD), laser Raman spectroscopy (LRS), and UV–vis diffuse reflectance spectroscopy (UV–vis DRS). The acid properties were investigated by the method of Hammett indicator and Pyridine adsorption infrared (Py-IR) spectroscopy. The results showed that the dispersion process of Nb{sub 2}O{sub 5} was performed by consuming surface hydroxyl groups of the amorphous SiO{sub 2} support. The aggregation of niobia species led to the formation of microcrystalline particles, so that there was no a clear monolayer dispersion capacity for Nb{sub 2}O{sub 5} supported on amorphous SiO{sub 2}. Furthermore, the catalytic activities of the as-prepared samples were evaluated by the condensation reaction of iso-butene (IB) and iso-butyraldehyde (IBA) to form 2,5-dimethyl-2,4-hexadiene (DMHD). The catalytic activities of the as-prepared samples for the condensation and their acid properties were strongly affected by the dispersion states. - Graphical abstract: The acid amount and strength of Nb{sub 2}O{sub 5}/SiO{sub 2} samples varied with the increase of Nb{sub 2}O{sub 5} loading. The catalytic activities of the as-prepared samples for the condensation and their acid properties were strongly affected by the dispersion states. - Highlights: • The dispersed process of Nb{sub 2}O{sub 5} was completed by consuming surface hydroxyl groups of SiO{sub 2}. • XRD quantitative phase analysis is not applicable for oxides dispersing on amorphous support. • The catalytic activity of Nb{sub 2}O{sub 5}/SiO{sub 2} is closely related to the dispersion state of SiO{sub 2}.

  5. Crystal structure analysis of lead free Ba{sub 1-x}La{sub x}[Ti{sub 0.5}(Fe{sub 0.5}Nb{sub 0.5}){sub 0.5}]{sub 1-x/4}O{sub 3} Ceramics

    SciTech Connect (OSTI)

    Patel, Piyush Kumar; Rani, Jyoti; Yadav, K. L. [Smart Materials Research Laboratory, Department of Physics Indian Institute of Technology, Roorkee-247667 (India)

    2012-06-05T23:59:59.000Z

    Single phase Ba{sub 1-x}La{sub x}[Ti{sub 0.5}(Fe{sub 0.5}Nb{sub 0.5}){sub 0.5}]{sub 1-x/4}O{sub 3} [referred as BT-LFN]; x=0, 0.02, 0.04 and 0.06 ceramics have been synthesized by solid - state reaction process and were characterized by X-ray diffraction technique. The microstructure of the ceramics was examined by field emission-scanning electron microscopy (FE-SEM).

  6. Phase transitions in K{sub 3}AlF{sub 6}

    SciTech Connect (OSTI)

    Abakumov, Artem M. [Department of Chemistry, Moscow State University, Moscow 119992 (Russian Federation)]. E-mail: abakumov@icr.chem.msu.ru; Rossell, Marta D. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Alekseeva, Anastasiya M. [Department of Chemistry, Moscow State University, Moscow 119992 (Russian Federation); Vassiliev, Sergey Yu. [Department of Chemistry, Moscow State University, Moscow 119992 (Russian Federation); Mudrezova, Svetlana N. [Department of Chemistry, Moscow State University, Moscow 119992 (Russian Federation); Tendeloo, Gustaaf van [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Antipov, Evgeny V. [Department of Chemistry, Moscow State University, Moscow 119992 (Russian Federation)

    2006-02-15T23:59:59.000Z

    Phase transitions in the elpasolite-type K{sub 3}AlF{sub 6} complex fluoride were investigated using differential scanning calorimetry, electron diffraction and X-ray powder diffraction. Three phase transitions were identified with critical temperatures T{sub 1}=132 deg. C, T{sub 2}=153 deg. C and T{sub 3}=306 deg. C. The {alpha}-K{sub 3}AlF{sub 6} phase is stable below T{sub 1} and crystallizes in a monoclinic unit cell with a=18.8588(2)A, b=34.0278(2)A, c=18.9231(1)A, {beta}=90.453(1){sup o} (a=2a{sub c}-c{sub c}, b=4b{sub c}, c=a{sub c}+2c{sub c}; a{sub c}, b{sub c}, c{sub c}-the basic lattice vectors of the face-centered cubic elpasolite structure) and space group I2/a or Ia. The intermediate {beta} phase exists only in very narrow temperature interval between T{sub 1} and T{sub 2}. The {gamma} polymorph is stable in the T{sub 2}sub 3} temperature range and has an orthorhombic unit cell with a=36.1229(6)A, b=17.1114(3)A, c=12.0502(3)A (a=3a{sub c}-3c{sub c}, b=2b{sub c}, c=a{sub c}+c{sub c}) at 250 deg. C and space group Fddd. Above T{sub 3} the cubic {delta} polymorph forms with a{sub c}=8.5786(4)A at 400 deg. C and space group Fm3-bar m. The similarity between the K{sub 3}AlF{sub 6} and K{sub 3}MoO{sub 3}F{sub 3} compounds is discussed.

  7. Catalytic process for control of NO<sub>x sub>emissions using hydrogen

    DOE Patents [OSTI]

    Sobolevskiy, Anatoly; Rossin, Joseph A.; Knapke, Michael J.

    2010-05-18T23:59:59.000Z

    A selective catalytic reduction process with a palladium catalyst for reducing NOx in a gas, using hydrogen as a reducing agent. A zirconium sulfate (ZrO<sub>2sub>)SO>4 sub>catalyst support material with about 0.01-2.0 wt. % Pd is applied to a catalytic bed positioned in a flow of exhaust gas at about 70-200.degree. C. The support material may be (ZrO<sub>2sub>--SiO>2sub>)SO>4sub>. H<sub>2sub>O and hydrogen may be injected into the exhaust gas upstream of the catalyst to a concentration of about 15-23 vol. % H<sub>2sub>O and a molar ratio for H<sub>2sub>/NO>x sub>in the range of 10-100. A hydrogen-containing fuel may be synthesized in an Integrated Gasification Combined Cycle power plant for combustion in a gas turbine to produce the exhaust gas flow. A portion of the fuel may be diverted for the hydrogen injection.

  8. Seismic Modelling for the Sub-Basalt Imaging Problem Including an Analysis and Development of the Boundary Element Method 

    E-Print Network [OSTI]

    Dobson, Andrew

    The north-east Atlantic margin (NEAM) is important for hydrocarbon exploration because of the growing evidence of hydrocarbon reserves in the region. However, seismic exploration of the sub-surface is hampered by large ...

  9. Thickness dependent functional properties of PbZr{sub 0.52}Ti{sub 0.48}O{sub 3}/La{sub 0.67}Sr{sub 0.33}MnO{sub 3} heterostructures

    SciTech Connect (OSTI)

    Barrionuevo, D.; Ortega, N.; Katiyar, R. S. [Department of Physics and Institute of Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); Kumar, A. [National Physical Laboratory (CSIR), Dr. K. S. Krishnan Road, New Delhi 110012 (India); Chatterjee, R. [Indian Institute of Technology, Hauz Khas, New Delhi (India); Scott, J. F. [Department of Physics and Institute of Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); Earth Science Department, University of Cambridge, Cambridge CB2 3EQ (United Kingdom)

    2013-12-21T23:59:59.000Z

    The ultra thin ferroelectric PbZr{sub 0.52}Ti{sub 0.48}O{sub 3} (PZT) films with various thicknesses ranging from 100 (P100) to 10 (P10) nm were grown on La{sub 0.67}Sr{sub 0.33}MnO{sub 3}/(LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} (LSMO/LSAT) (001) substrates deposited by pulsed laser deposition technique. The x-ray diffraction patterns of the heterostructures show only (00l) (l?=?1 and/or 2) reflections corresponding to the LSAT substrate, PZT, and LSMO layers. The atomic force microscopy studies show that the root mean square surface roughnesses of P100 and P10 films are 2.39 and 0.99?nm, respectively. An increase of both real (??) and imaginary (??) permittivities was observed when thickness of PZT increases from 10?nm to 100?nm. Temperature dependent ?? presents an anomaly, related to ferromagnetic-metal to paramagnetic-insulator transition of the LSMO, in the range of 350–500?K. The dielectric anomalies and magnetic phase transition temperature shifted to the lower temperature values with decrease in the PZT films thicknesses. The values of the remanent polarization (P{sub r}) and coercive field (E{sub c}) of the heterostructures were in the range of 24–42??C/cm{sup 2}–170–1300?kV/cm. An appreciable increase of saturated magnetization (M{sub s}) was observed with increase of PZT layer thickness. The average M{sub s} values of PZT/LSMO heterostructure were 170, 150, 100, and 45?emu/cm{sup 3} for 100, 50, 25, and 10?nm at 300?K, respectively. Enhancement in magnetization with increase in PZT thickness may be due to the interface effect between PZT/LSMO layers.

  10. Temperature-dependent structural studies of mullite-type Bi{sub 2}Fe{sub 4}O{sub 9}

    SciTech Connect (OSTI)

    Murshed, M. Mangir [Chemische Kristallographie fester Stoffe, Universitaet Bremen, Leobener Strasse, D-28359 Bremen (Germany); Nenert, Gwilherm [Institut Laue Langevin, 6 rue Jules Horowitz, 38042 Grenoble (France); Burianek, Manfred [Kristallographie, Universitaet Koeln, Greinstrasse 6, 50939 Koeln (Germany); Robben, Lars [Chemische Kristallographie fester Stoffe, Universitaet Bremen, Leobener Strasse, D-28359 Bremen (Germany); Muehlberg, Manfred [Kristallographie, Universitaet Koeln, Greinstrasse 6, 50939 Koeln (Germany); Schneider, Hartmut [Kristallographie, Universitaet Koeln, Greinstrasse 6, 50939 Koeln (Germany); Kristallographie, FB Geowissenschaften, Universitaet Bremen, Klagenfurter Strasse, D-28359 Bremen (Germany); Fischer, Reinhard X. [Kristallographie, FB Geowissenschaften, Universitaet Bremen, Klagenfurter Strasse, D-28359 Bremen (Germany); Gesing, Thorsten M., E-mail: gesing@uni-bremen.de [Chemische Kristallographie fester Stoffe, Universitaet Bremen, Leobener Strasse, D-28359 Bremen (Germany); Kristallographie, FB Geowissenschaften, Universitaet Bremen, Klagenfurter Strasse, D-28359 Bremen (Germany)

    2013-01-15T23:59:59.000Z

    We report on the temperature-dependent structural studies on the mullite-type Bi{sub 2}Fe{sub 4}O{sub 9} compound. The crystal structures were determined using both powder X-ray diffraction and single crystal neutron diffraction. The thermal expansion of the cell parameters from smallest to largest occurred in the order aregion of choice. The anisotropic thermal expansion was monitored with respect to the expansion coefficients, anisotropy factor, and polyhedral geometry. At 900 K an abrupt change of the anisotropy factor is observed which correlates with a slope in the BiO{sub 6} polyhedral volume. At the same temperature the FeO{sub 4} tetrahedral distortion starts to increase. The temperature-dependent stereochemically activity of the Bi{sup 3+} 6s{sup 2} lone electron pair was probed by the absolute value of eccentricity parameter. This parameter shows a significant drop at around 773 K. Additionally, the average crystal size and micro-strain of the powder samples were studied. A healing of intrinsic defects is observed with respect to a decreasing micro-strain followed by crystal growth above about 900 K. The temperature-dependent infrared spectra were described in three distinct zones. Deconvolution of the absorption features between 370 cm{sup -1} and 1000 cm{sup -1} required nine fitted bands, and the decomposed Pseudo-Voigt elements were assigned to Fe-O stretching, Fe-O-Fe bending and O-Fe-O bending vibrations. The shift of the observed modes was described with respect to temperature. An effective linewidth parameter {Delta}corr was determined by autocorrelation analysis between 740 cm{sup -1} and 900 cm{sup -1} for each temperature-dependent spectrum. The break of the slope of {Delta}corr at about 773 K was interpreted as the change of some vibrational modes of the FeO{sub 4} tetrahedra. The intrinsic effects observed around 773 K are responsible for extrinsic parameter changes found around 900 K. - Graphical abstract: Temperature-dependent stereochemical activity (eccentricity |{Phi}{sub i}|) of the Bi{sup 3+} 6s{sup 2} lone electron pair directing in the non-bonded region of the Bi-O coordination in the Bi{sub 2}Fe{sub 4}O{sub 9} iron framework (given as polyhedra). Highlights: Black-Right-Pointing-Pointer Complex expansion-contraction mechanism explains anisotropic thermal expansion. Black-Right-Pointing-Pointer Bi 6s{sup 2} lone electron pair sphericity influences analyses by FTIR autocorrelation. Black-Right-Pointing-Pointer Intrinsic effects at 773 K are responsible for extrinsic parameter changes at 900 K.

  11. Synthesis and crystal structure of new layered BaNaSc(BO{sub 3}){sub 2} and BaNaY(BO{sub 3}){sub 2} orthoborates

    SciTech Connect (OSTI)

    Seryotkin, Yurii V., E-mail: yuvs@uiggm.nsc.r [Institute of Geology and Mineralogy RAS, 3, Koptyuga avenue, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 2, Pirogova street, 630090 Novosibirsk (Russian Federation); Bakakin, Vladimir V. [Institute of Inorganic Chemistry RAS, 3, Lavrentieva avenue, 630090 Novosibirsk (Russian Federation); Kokh, Aleksandr E.; Kononova, Nadezhda G. [Institute of Geology and Mineralogy RAS, 3, Koptyuga avenue, 630090 Novosibirsk (Russian Federation); Svetlyakova, Tatyana N. [Institute of Geology and Mineralogy RAS, 3, Koptyuga avenue, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 2, Pirogova street, 630090 Novosibirsk (Russian Federation); Kokh, Konstantin A. [Institute of Geology and Mineralogy RAS, 3, Koptyuga avenue, 630090 Novosibirsk (Russian Federation); Drebushchak, Tatyana N. [Novosibirsk State University, 2, Pirogova street, 630090 Novosibirsk (Russian Federation); Institute of Solid State Chemistry and Mechanochemistry RAS, 18, Kutateladze street, 630128 Novosibirsk (Russian Federation)

    2010-05-15T23:59:59.000Z

    Crystals of two new layered BaNaSc(BO{sub 3}){sub 2} (I) and BaNaY(BO{sub 3}){sub 2} (II) orthoborates are grown from the melt-solution by the spontaneous crystallization onto the platinum loop. Single crystal X-ray analysis showed that the compounds are isostructural with the space group R3-bar, a=5.23944(12) and 5.3338(2) A, and c=34.5919(11) and 35.8303(19) A for I and II, respectively, Z=6. The distinctive feature of the structure is the close-packed composite anion-cation (Ba,Na)(BO{sub 3}) layers. The layers are combined into the base building packages of two types: {l_brace}M{sup 3+}[Ba{sup 2+}(BO{sub 3}){sup 3-}]{sub 2}{r_brace}{sup +} and {l_brace}M{sup 3+}[Na{sup +}(BO{sub 3}){sup 3-}]{sub 2}{r_brace}{sup -}, where M is Sc or Y. Neutral-charge two-package (four-layer) blocks are stacked by the rhombohedral principle into twelve layers of the cubic packing. - Graphical abstract: The distinctive feature of new orthoborate crystals BaNaSc(BO{sub 3}){sub 2} and BaNaY(BO{sub 3}){sub 2} is the combination of base building packages of two types: {l_brace}M{sup 3+}[Ba{sup 2+}(BO{sub 3}){sup 3-}]{sub 2}{r_brace}{sup +} and {l_brace}M{sup 3+}[Na{sup +}(BO{sub 3}){sup 3-}]{sub 2}{r_brace}{sup -}, where M is Sc or Y.

  12. Luminescence properties of Eu-activated alkaline and alkaline-earth silicate Na{sub 2}Ca{sub 3}Si{sub 6}O{sub 16}

    SciTech Connect (OSTI)

    Wang, Jing [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Huang, Yanlin, E-mail: huang@suda.edu.cn [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Wang, Xigang, E-mail: wangxigang@suda.edu.cn [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Qin, Lin [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Seo, Hyo Jin, E-mail: hjseo@pknu.ac.kr [Department of Physics and Center for Marine-Integrated Biomedical Technology, Pukyong National University, Busan 608-737 (Korea, Republic of)

    2014-07-01T23:59:59.000Z

    Highlights: • A novel yellow-emitting alkaline and alkaline-earth silicate Na{sub 2}Ca{sub 3}Si{sub 6}O{sub 16}:Eu{sup 2+} was first developed. • Under excitation with UV or near UV light the silicate presents broad emission band centered at 580 nm. - Abstract: Yellow-emitting phosphors of Na{sub 2}Ca{sub 3}Si{sub 6}O{sub 16}:Eu{sup 2+} was prepared by wet chemistry sol–gel method. X-ray powder diffraction and SEM measurements were applied to characterize the structure and morphology, respectively. The luminescence properties were investigated by the photoluminescence excitation and emission spectra, decay curve (lifetimes), CIE coordinates and the internal quantum efficiencies. The excitation spectra can match well with the emission light of near UV-LED chips (360–400 nm). Na{sub 2}Ca{sub 3}Si{sub 6}O{sub 16}:Eu{sup 2+} presents a symmetric emission band from 4f{sup 6}5d{sup 1} ? 4f{sup 7}({sup 8}S{sub 7/2}) transitions of Eu{sup 2+} ions on doping below 3.0 mol%. On increasing Eu-doping levels, the sample contains two kinds of emission centers, i.e., Eu{sup 2+} and Eu{sup 3+} ions, which present the characteristic broad band (5d ? 4f) and narrower (4f ? 4f) luminescence lines, respectively. The energy transfer, the luminescence thermal stability (activation energy ?E for thermal quenching) and luminescence mechanism of Na{sub 2}Ca{sub 3}Si{sub 6}O{sub 16}:Eu{sup 2+} phosphors were discussed by analyzing the relationship between the luminescence characteristics and the crystal structure.

  13. Highly tunable electron transport in epitaxial topological insulator (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} thin films

    SciTech Connect (OSTI)

    He Xiaoyue; Guan Tong; Wang Xiuxia; Feng Baojie; Cheng Peng; Chen Lan; Li Yongqing; Wu Kehui [Institute of Physics, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2012-09-17T23:59:59.000Z

    Atomically smooth, single crystalline (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} films have been grown on SrTiO{sub 3}(111) substrates by molecular beam epitaxy. A full range of Sb-Bi compositions have been studied in order to obtain the lowest possible bulk conductivity. For the samples with optimized Sb compositions (x=0.5{+-}0.1), the carrier type can be tuned from n-type to p-type across the whole thickness with the help of a back-gate. Linear magnetoresistance has been observed at gate voltages close to the maximum in the longitudinal resistance of a (Bi{sub 0.5}Sb{sub 0.5}){sub 2}Te{sub 3} sample. These highly tunable (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} thin films provide an excellent platform to explore the intrinsic transport properties of the three-dimensional topological insulators.

  14. Crystal structure of Sr{sub 6}Y{sub 2}Al{sub 4}O{sub 15}: XRD refinements and first-principle calculations

    SciTech Connect (OSTI)

    Wang Chunhai, E-mail: chwang81@163.com [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, CAEP, Mianyang 621900 (China) and Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Guo Dongfang [College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000 (China); Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Li Zhaofei; Wang Xiaoming; Lin Jianhua [Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Zeng Zhengzhi [College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000 (China); Jing Xiping, E-mail: xpjing@pku.edu.cn [Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)

    2012-08-15T23:59:59.000Z

    The ternary oxide phase Sr{sub 6}Y{sub 2}Al{sub 4}O{sub 15} (SYA) was synthesized and the crystal structure was determined by using the X-ray powder diffraction data. Structure of the phase can be considered as an oxygen-deficient perovskite Sr(Y{sub 1/3}Al{sub 2/3})O{sub 2.5} and has a monoclinic C2 (S.G. No. 5) unit cell with the unit cell parameters: a=17.597(1) A, b=5.7408(1) A, c=7.6860(1) A, {beta}=90.7659(3) Degree-Sign , V{sub cell}=776.37(1) A{sup 3}, Z=2. By bond parameter analysis and first-principle calculations, we confirmed the reasonability of our crystal structure model. According to the calculated band structure, SYA has an indirect band gap {approx}4.3 eV and a direct band gap {approx}4.4 eV, which is wide to be transparent to UV and visible lights. We also synthesized other rare-earth isomorphs Sr{sub 6}Ln{sub 2}Al{sub 4}O{sub 15} (Ln=Tb, Dy, Ho, Er, Tm, Yb and Lu) and obtained their cell parameters. - Graphical abstract: Sr{sub 6}Y{sub 2}Al{sub 4}O{sub 15} has a monoclinic unit cell with space group C2 (5) with unit cell parameters: a=17.597(1) A, b=5.7408(1) A, c=7.6860(1) A, {beta}=90.7659(3) Degree-Sign . Highlights: Black-Right-Pointing-Pointer Sr{sub 6}Y{sub 2}Al{sub 4}O{sub 15} (SYA) has an oxygen-deficient perovskite structure Sr(Y{sub 1/3}Al{sub 2/3})O{sub 2.5}. Black-Right-Pointing-Pointer SYA shows C2 symmetry: a=17.597(1) A, b=5.7408(1) A, c=7.6860(1) A, {beta}=90.7659(3) Degree-Sign . Black-Right-Pointing-Pointer SYA has an indirect band gap {approx}4.3 eV and a direct band gap {approx}4.4 eV.

  15. Inhibition effects of N,N-dimethylalkylamines and octanethiol on iron corrosion in anhydrous acetonitrile solution containing FeCl{sub 3}

    SciTech Connect (OSTI)

    Aramaki, Kunitsugu; Kikuchi, Takeshi

    2000-05-01T23:59:59.000Z

    Polarization and impedance measurements were carried out on an iron electrode in an anhydrous acetonitrile solution of 0.1 M LiClO{sub 4} and 0.01 M FeCl{sub 3} containing organic corrosion inhibitors. The inhibitors investigated were N,N-dimethylalkylamines C{sub n}H{sub 2n+1}N(CH{sub 3}){sub 2} (C{sub n}DMA, n = 8, 12, 16, and 18) and octanethiol C{sub 8}H{sub 17}SH (C{sub 8}T). These compounds suppressed both cathodic and anodic processes of iron corrosion in the acetonitrile solution. The double-layer capacitances obtained from impedance data for the electrode inhibited with C{sub n}DMA were markedly lower in the potential region of the cathodic polarization curve than those for the uninhibited electrode. Ultraviolet and visible spectra of the FeCl{sub 3} acetonitrile solution containing C{sub n}DMA revealed the formation of a Fe{sup 3+} complex cation with C{sub n}DMA, and joint adsorption of the complex cation with Cl{sup {minus}} on the iron surface was substantiated by X-ray photoelectron spectroscopy of the surface treated with the solution. A surface thiolate of C{sub 8}T was formed by its chemisorption on the iron surface, resulting in a decrease in the double-layer capacitance and the cathodic and anodic current densities, respectively.

  16. Thermal conductivity of Zn{sub 4{minus}x}Cd{sub x}Sb{sub 3} solid solutions

    SciTech Connect (OSTI)

    Caillat, T.; Borshchevsky, A.; Fleurial, J.P.

    1997-07-01T23:59:59.000Z

    {beta}-Zn{sub 4}Sb{sub 3} was recently identified at the Jet Propulsion Laboratory as a new high performance p-type thermoelectric material with a maximum dimensionless thermoelectric figure of merit ZT of 1.4 at a temperature of 673K. A usual approach, used for many state-of-the-art thermoelectric materials, to further improve ZT values is to alloy {beta}-Zn{sub 4}Sb{sub 3} with isostructural compounds because of the expected decrease in lattice thermal conductivity. The authors have grown Zn{sub 4{minus}x}Cd{sub x}Sb{sub 3} crystals with 0.2 {le} x < 1.2 and measured their thermal conductivity from 10 to 500K. The thermal conductivity values of Zn{sub 4{minus}x}Cd{sub x}Sb{sub 3} alloys are significantly lower than those measured for {beta}-Zn{sub 4}Sb{sub 3} and are comparable to its calculated minimum thermal conductivity. A strong atomic disorder is believed to be primarily at the origin of the very low thermal conductivity of these materials which are also fairly good electrical conductors and are therefore excellent candidates for thermoelectric applications.

  17. Strain induced Z{sub 2} topological insulating state of ?-As{sub 2}Te{sub 3}

    SciTech Connect (OSTI)

    Pal, Koushik [Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064 (India); Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064 (India); Waghmare, Umesh V., E-mail: waghmare@jncasr.ac.in [Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064 (India)

    2014-08-11T23:59:59.000Z

    Topological insulators are non-trivial quantum states of matter which exhibit a gap in the electronic structure of their bulk form, but a gapless metallic electronic spectrum at the surface. Here, we predict a uniaxial strain induced electronic topological transition (ETT) from a band to topological insulating state in the rhombohedral phase (space group: R3{sup ¯}m) of As{sub 2}Te{sub 3} (?-As{sub 2}Te{sub 3}) through first-principles calculations including spin-orbit coupling within density functional theory. The ETT in ?-As{sub 2}Te{sub 3} is shown to occur at the uniaxial strain ?{sub zz}?=??0.05 (?{sub zz}?=?1.77?GPa), passing through a Weyl metallic state with a single Dirac cone in its electronic structure at the ? point. We demonstrate the ETT through band inversion and reversal of parity of the top of the valence and bottom of the conduction bands leading to change in the ?{sub 2} topological invariant ?{sub 0} from 0 to 1 across the transition. Based on its electronic structure and phonon dispersion, we propose ultra-thin films of As{sub 2}Te{sub 3} to be promising for use in ultra-thin stress sensors, charge pumps, and thermoelectrics.

  18. Fundamental research on gas–solid reaction between CO{sub 2} and Li{sub 2}CuO{sub 2} linking application for solid CO{sub 2} absorbent

    SciTech Connect (OSTI)

    Oh-ishi, Katsuyoshi, E-mail: oh-ishi@kc.chuo-u.ac.jp; Matsukura, Yusuke; Okumura, Takeshi; Matsunaga, Yuuki; Kobayashi, Ryota

    2014-03-15T23:59:59.000Z

    We compared reactivity between CO{sub 2} and Li{sub 2}CuO{sub 2} with that between CO{sub 2} and Li{sub 4}SiO{sub 4} by using XRD, SEM observation, and thermogravimetry in order to study fundamentally a potential of Li{sub 2}CuO{sub 2} oxide for application to solid CO{sub 2} absorbents. The CO{sub 2} absorption ability of Li{sub 2}CuO{sub 2} was examined by measuring rate constants for the gas–solid reaction between perfectly single-phase Li{sub 2}CuO{sub 2} and CO{sub 2} at various temperatures in 100 vol% CO{sub 2} atmosphere using the rate theory with thermogravimetry using rapid heating. The measured rate constants were compared with those reported previously for Li{sub 4}SiO{sub 4} at various temperatures. Almost no difference was found between these rate constants of Li{sub 2}CuO{sub 2} and Li{sub 4}SiO{sub 4} at temperatures less than 660 °C, but at temperatures higher than 670 °C, the rate constants of Li{sub 2}CuO{sub 2} were greater than those of Li{sub 4}SiO{sub 4}. These results demonstrate that Li{sub 2}CuO{sub 2} can outstrip the ability of Li{sub 4}SiO{sub 4} to absorb CO{sub 2}. Moreover, different from Li{sub 4}SiO{sub 4}, the CO{sub 2} absorption ability of Li{sub 2}CuO{sub 2} decays only slightly, even if the atmospheric CO{sub 2} concentration decreases. -- Graphical abstract: Surface changes of Li{sub 2}CuO{sub 2} and Li{sub 4}SiO{sub 4} particles by progression of the gas–solid reactions between CO{sub 2} and these oxides. Highlights: • The CO{sub 2} absorption ability of perfect single-phase Li{sub 2}CuO{sub 2} is reported. • Results show that Li{sub 2}CuO{sub 2} can outstrip the Li{sub 4}SiO{sub 4} ability to absorb CO{sub 2}. • The oxide particle CO{sub 2} absorption ability is size- and surface-state-dependent.

  19. Study of calcium-containing orthophosphates of NaZr{sub 2}(PO{sub 4}){sub 3} structural type by high-temperature X-ray diffraction

    SciTech Connect (OSTI)

    Orlova, A. I.; Kanunov, A. E., E-mail: a.kanunov@mail.ru [Nizhni Novgorod State University (Russian Federation); Samoilov, S. G.; Kazakova, A. Yu.; Kazantsev, G. N. [Leipunsky Institute of Physics and Power Engineering (Russian Federation)] [Leipunsky Institute of Physics and Power Engineering (Russian Federation)

    2013-03-15T23:59:59.000Z

    Orthophosphates Ca{sub 0.5}Ti{sub 2}(PO{sub 4}){sub 3}, Ca{sub 0.5}Zr{sub 2}(PO{sub 4}){sub 3}, Ca{sub 0.75}Zr{sub 2}(SiO{sub 4}){sub 0.5}(PO{sub 4}){sub 2.5}, and CaMg{sub 0.5}Zr{sub 1.5}(PO{sub 4}){sub 3} (structural type NaZr{sub 2}(PO{sub 4}){sub 3}), having different occupancies of interframework positions by calcium, have been prepared by the sol-gel method with the subsequent thermal treatment of dried gels and investigated by IR spectroscopy and X-ray diffraction. The analytical indexing of X-ray diffraction patterns is performed within the sp. gr. R3{sup -}. High-temperature X-ray diffraction was used to investigate the behavior of the orthophosphates upon heating: thermal expansion in the temperature range of 20-610 Degree-Sign C (up to 500 Degree-Sign C for Ca{sub 0.5}Zr{sub 2}(PO{sub 4}){sub 3}). The coefficients of thermal expansion are calculated from the shift of diffraction peaks. The unit-cell parameters of crystals at different temperatures are determined. The dependences of thermal expansion and its anisotropy on the occupancy of cation M positions by calcium are revealed.

  20. Dissociative-recombination product states and the dissociation energy D<sub>0sub> of Ne<sub>2sub>+

    SciTech Connect (OSTI)

    Hardy, K. A.; Peterson, J. R.; Ramos, G.; Sheldon, J. W.

    1998-02-28T23:59:59.000Z

    Final product states of Ne<sub>2sub>+ dissociative recombination were studied using time-of-flight spectroscopy to determine the kinetic energies released. The dissociative recombination occurred in a sustained discharge in the presence of a variable magnetic field and discharge voltage, at pressures of 5-15 mTorr. Under different conditions various excited states were observed ranging from the lowest 3s metastable states to higher Rydbcrg states within 0.000 54 eV of the dissociation limit. From their narrow widths, it is deduced that these higher states arose from Ne<sub>2sub>+ ions with subthermal energies. From two of these narrow distributions, we obtain an improved value for the dissociation limit D<sub>0sub>(Ne>2sub>+)= 1.26±0.02 eV.

  1. Compact Li-doped Gd{sub 2}Ti{sub 2}O{sub 7} prepared with LiO{sub 0.5} self-flux

    SciTech Connect (OSTI)

    Wen, L.C.; Hsieh, H.Y.; Chang, S.C.; Lin, M.Y.; Lee, Y.H.; Su, W.P. [Department of Chemistry, Tamkang University, New Taipei City 25137, Taiwan (China); Kao, H.-C.I., E-mail: kaohci@mail.tku.edu.tw [Department of Chemistry, Tamkang University, New Taipei City 25137, Taiwan (China); Sheu, H.S.; Jang, L.Y. [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Lee, M.C.; Lee, Y.S. [Institute of Nuclear Energy Research, Atomic Energy Council, Longtan 32546, Taiwan (China)

    2014-02-01T23:59:59.000Z

    Graphical abstract: Left figure is the unit cell a-axis of the GLT-2L (?), GLT (?) and GT (?) as a function of x. Both of the GLT-2L and GLT have the same results so that they have the same chemical formula, (Gd{sub 2?x}Li{sub x})Ti{sub 2}O{sub 7?x}, in which GT has a formula of Gd{sub 2?x}Ti{sub 2}O{sub 7?x}. Relative densities are shown in the right figure. GLT-2L (?) has higher values than GLT (?). 2x moles of LiO{sub 0.5} were added as a self-flux to prepare GLT-2L at 1250 °C, which was about 300 °C lowered than required without the co-existence of the flux and Li ion substitution. - Highlights: • A new series of compounds with a formula as (Gd{sub 2?x}Li{sub x})Ti{sub 2}O{sub 7?x} was synthesized. • Each GLT-2L sample contains (Gd{sub 2?x}Li{sub x})Ti{sub 2}O{sub 7?x} and 2x moles of LiO{sub 0.5} self-flux. • 1250 °C was used to prepare the GLT-2L samples; 300 °C lower than required. • Electrical conductivity of the GLT-2L is not affected by the presence of the flux. • Average valence of the Ti ions is slightly less than 4. - Abstract: A series of (Gd{sub 2?x}Li{sub x})Ti{sub 2}O{sub 7?x} with x = 0.040–0.110 was first reported. Parent compound with 2x moles of LiO{sub 0.5} self-flux was prepared at 1250 °C and abbreviated as GLT-2L. Relative density of all the samples is higher than 92%. By the addition of flux and Li ions substitution, preparation temperature is lowered for more than 300 °C. Comparing the unit cell a-axis, GLT with a formula as (Gd{sub 2?x}Li{sub x})Ti{sub 2}O{sub 7?x} without flux addition has exactly the same as the GLT-2L with the same x. By the addition of flux, materials become more compact and grains grow bigger for the GLT-2L than the corresponding GLT samples. Electrical conductivity of a GLT-2L with x = 0.110 at 700 °C is 3 times larger than the measurements done by other research groups in the Gd{sub 2}Ti{sub 2}O{sub 7}. In order to demonstrate the successful substitution of the Li ion into the Gd site, a series of GT samples was prepared with a formula of Gd{sub 2?x}Ti{sub 2}O{sub 7?1.5x}. With the same amount of x, every GLT samples have a longer unit cell a-axis than that of the GT. The difference is caused by the substitution of the Li ion into the Gd site. Valence of the Ti atoms of the GLT-2L samples is slightly less than 4 studied by the XANES spectroscopy.

  2. Magnetic behavior of LaMn{sub 2}(Si{sub (1?x)}Ge{sub x}){sub 2} compounds characterized by magnetic hyperfine field measurements

    SciTech Connect (OSTI)

    Bosch-Santos, B., E-mail: brianna@usp.br; Carbonari, A. W.; Cabrera-Pasca, G. A.; Saxena, R. N. [Instituto de Pesquisas Energéticas e Nucleares, University of São Paulo, 05508-000 São Paulo (Brazil)

    2014-05-07T23:59:59.000Z

    The temperature dependence of the magnetic hyperfine field (B{sub hf}) at Mn atom sites was measured in LaMn{sub 2}(Si{sub (1?x)}Ge{sub x}){sub 2}, with 0???x???1, compounds with perturbed ??? angular correlation spectroscopy using {sup 111}In({sup 111}Cd) as probe nuclei in the temperature range from 20?K to 480?K. The results show a transition from antiferromagnetic to ferromagnetic ordering for all studied compounds when Ge gradually replaces Si and allowed an accurate determination of the Néel temperature (T{sub N}) for each compound. It was observed that T{sub N} decreases when Ge concentration increases. Conversely, the Curie temperature increases with increase of Ge concentration. This remarkable change in the behavior of the transition temperatures is discussed in terms of the Mn-Mn distance and ascribed to a change in the exchange constant J{sub ex}.

  3. Solar reduction of CO.sub.2

    DOE Patents [OSTI]

    Jensen, Reed J. (121 La Vista Dr., Los Alamos, NM 87544); Lyman, John L. (Los Alamos, NM); King, Joe D. (Los Alamos, NM); Guettler, Robert D. (Los Alamos, NM)

    2000-01-01T23:59:59.000Z

    The red shift of the absorption spectrum of CO.sub.2 with increasing temperature permits the use of sunlight to photolyze CO.sub.2 to CO. The process of the present invention includes: preheating CO.sub.2 to near 1800 K; exposing the preheated CO.sub.2 to sunlight, whereby CO, O.sub.2 and O are produced; and cooling the hot product mix by rapid admixture with room temperature CO.sub.2. The excess thermal energy may be used to produce electricity and to heat additional CO.sub.2 for subsequent process steps. The product CO may be used to generate H.sub.2 by the shift reaction or to synthesize methanol.

  4. Magnetic properties and magnetocaloric effect in La{sub 0.7}Nd{sub 0.3}Fe{sub 13-x}Si{sub x} compounds

    SciTech Connect (OSTI)

    Mican, S. [Babes-Bolyai University, Faculty of Physics, RO-400084, Cluj-Napoca (Romania); Tetean, R., E-mail: romulus.tetean@phys.ubbcluj.ro [Babes-Bolyai University, Faculty of Physics, RO-400084, Cluj-Napoca (Romania)

    2012-03-15T23:59:59.000Z

    The structural, magnetic and magnetocaloric properties in the cubic NaZn{sub 13}-type La{sub 0.7}Nd{sub 0.3}Fe{sub 13-x}Si{sub x} compounds with x=1.2, 1.4, 1.6 and 1.8 are reported. All of the investigated samples are ferromagnetically ordered. The Fe saturation moment at 5 K is independent of Si concentration, having a value of 2.05{+-}0.09 {mu}{sub B}, which suggests a high degree of localization. The Curie temperatures increase almost linearly with the increase in silicon concentration. The large {Delta}S{sub M} values obtained for samples with low Si content are mainly due to the first-order character of the transition at T{sub C}. The field-induced transition above T{sub C} causes an asymmetric broadening of the {Delta}S{sub M} peak towards higher temperatures for higher applied fields. With increasing Si content, the first-order character of the transition at T{sub C} is diminished, leading to lower {Delta}S{sub M} values. The potential use of these materials in magnetic refrigeration is discussed. - Graphical abstract: Transition from a first-order to a second-order magnetic phase transition at T{sub C} on La{sub 0.7}Nd{sub 0.3}Fe{sub 13-x}Si{sub x}. Highlights: Black-Right-Pointing-Pointer Magnetic properties and magnetocaloric effect in La{sub 0.7}Nd{sub 0.3}Fe{sub 13-x}Si{sub x} compounds are reported. Black-Right-Pointing-Pointer Transition from a first-order to a second-order type magnetic phase transition at T{sub C} with increasing silicon content. Black-Right-Pointing-Pointer Itinerant electronic metamagnetic transition above the Curie temperature. Black-Right-Pointing-Pointer High values of the magnetic entropy changes in 2 T magnetic field.

  5. Electronic structure and magnetism of Mn{sub 12}O{sub 12} clusters

    SciTech Connect (OSTI)

    Pederson, M.R. [Complex Systems Theory Branch-6692, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Complex Systems Theory Branch-6692, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Khanna, S.N. [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)] [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)

    1999-01-01T23:59:59.000Z

    To address the ferrimagnetic state of the Mn{sub 12} acetate matrix [Mn{sub 12}O{sub 12}(CH{sub 3}COO){sub 16}(H{sub 2}O){sub 4}] we have performed all-electron gradient-corrected density-functional calculations on (MnO){sub n} with n=1, 2, 4, and 12. In contrast to bulk MnO which is antiferromagnetic, the small (MnO){sub n} (n=1, 2, and 4) clusters are ferromagnetic with Mn moments of 5.0{mu}{sub B} but the ground state of Mn{sub 12}O{sub 12} is ferrimagnetic with a total magnetic moment of 20.0{mu}{sub B} as observed experimentally. The inner Mn sites in Mn{sub 12}O{sub 12} are found to have localized moments of 4.1{mu}{sub B} which are antiferromagnetically coupled to two types of outer Mn with moments of 4.2{mu}{sub B}. The cluster is shown to be marked by ionic as well as covalent bonds between Mn d and O p electrons and a strong intracluster magnetic coupling. {copyright} {ital 1999} {ital The American Physical Society}

  6. Hydrothermal synthesis, structure, and magnetic properties of Pu(SeO{sub 3}){sub 2}

    SciTech Connect (OSTI)

    Bray, Travis H. [Department of Chemistry and Biochemistry and Center for Actinide Science, Auburn University, Auburn, AL 36849 (United States); Skanthakumar, S.; Soderholm, L. [Chemistry Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Sykora, Richard E. [Department of Chemistry, University of South Alabama, Mobile, AL 36688 (United States); Haire, Richard G. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Albrecht-Schmitt, Thomas E. [Department of Chemistry and Biochemistry and Center for Actinide Science, Auburn University, Auburn, AL 36849 (United States)], E-mail: albreth@auburn.edu

    2008-03-15T23:59:59.000Z

    The reaction between PuO{sub 2} and SeO{sub 2} under mild hydrothermal conditions results in the formation of Pu(SeO{sub 3}){sub 2} as brick-red prisms. This compound adopts the Ce(SeO{sub 3}){sub 2} structure type, and consists of one-dimensional chains of edge-sharing [PuO{sub 8}] distorted bicapped trigonal prisms linked by [SeO{sub 3}] units into a three-dimensional network. Crystallographic data: Pu(SeO{sub 3}){sub 2}, monoclinic, space group P2{sub 1}/n, a=6.960(1) A, b=10.547(2) A, c=7.245(1) A, {beta}=106.880(9){sup o}, V=508.98(17) A{sup 3}, Z=4 (T=193 K), R(F)=2.92% for 83 parameters with 1140 reflections with I>2{sigma}(I). Magnetic susceptibility data for Pu(SeO{sub 3}){sub 2} are linear from 35 to 320 K and yield an effective moment of 2.71(5) {mu}{sub B} and a Weiss constant of -500(5) K. - Graphical abstract: A depiction of the three-dimensional structure of Pu(SeO{sub 3}){sub 2} formed from the interconnection of one-dimensional chains of edge-sharing PuO{sub 8} dodecahedra by selenite anions.

  7. Improvement of the physical properties of novel (1 ? y) Co{sub 0.8}Cu{sub 0.2}Fe{sub 2}O{sub 4} + (y) SrTiO{sub 3} nanocomposite

    SciTech Connect (OSTI)

    Ahmed, M.A., E-mail: moala47@hotmail.com [Materials Science Lab (1), Physics Department, Faculty of Science, Cairo University, Giza (Egypt); Mansour, S.F.; Abdo, M.A. [Physics Department, Faculty of Science, Zagazig University (Egypt)

    2013-05-15T23:59:59.000Z

    Graphical abstract: The ME coefficient as a function of magnetic field for the composites (1 ? y) Co{sub 0.8}Cu{sub 0.2}Fe{sub 2}O{sub 4} + (y) SrTiO{sub 3} (y = 40, 50, 60 and 80%). Highlights: ? T{sub C} and M{sub s} decrease with the increase of SrTiO{sub 3} concentration. ? The P–E hysteresis loops were observed for all compositions. ? The maximum ME coefficient was observed for the composite with 60% SrTiO{sub 3}. - Abstract: Magnetoelectric (ME) nanocomposites (1 ? y) Co{sub 0.8}Cu{sub 0.2}Fe{sub 2}O{sub 4} + (y) SrTiO{sub 3} (y = 40, 50, 60, 80 and 100%) were prepared by standard ceramic method. Phase formation was checked using X-ray diffraction analysis. Both saturation magnetization (M{sub s}) and Curie temperature (T{sub C}) decrease with increasing SrTiO{sub 3} content. Temperature dependence of the dielectric constant reveals two maxima, one about 550 K corresponds to non-stoichiometry and lattice distortions while the second around 900 K corresponds to the Curie temperature (T{sub C}). The large value of ME output is due to the strain induced by lattice distortion in the ferrite phase by Jahn–Teller ions like Cu. Hence, Jahn–Teller effect in the ferrite leads to polarization in the piezoelectric phase.

  8. Adsorption sites in zeolites A and X probed by competitive adsorption of H{sub 2} with N{sub 2} or O{sub 2} : implications for N{sub 2}/O{sub 2} separation.

    SciTech Connect (OSTI)

    Eckert, J.

    1998-08-31T23:59:59.000Z

    We determine details of the adsorption of O{sub 2} or N{sub 2} in Na{sup +} and Li{sup +} exchanged zeolites by way of their effect on coadsorbed H{sub 2} molecules using inelastic neutron scattering (INS) techniques. Adsorption site occupancies are deduced with the aid of MC simulations. The expected stronger binding of N{sub 2} (compared with O{sub 2}) in LiX is evident in coadsorption spectra of N{sub 2} or O{sub 2} with H{sub 2}.

  9. Vortex line pinning in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} single crystals with columnar defects

    SciTech Connect (OSTI)

    van der Beek, C.J.; Vinokur, V.M.; Crabtree, G.W. [Argonne National Lab., IL (United States); Schmidt, B.; Konczykowski, M. [CEA-Ecole Polytechnique, 91 - Palaiseau (France). Lab. d`Etudes des Solides Irradies

    1994-05-01T23:59:59.000Z

    The ac transmittivity of heavy-ion irradiated Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} single crystals shows a sharp cusp as function of the dc field orientation with respect to the columnar defects. This unambiguously demonstrates the connected nature of vortices in these samples. In contrast, the irreversibility line does not reveal a cusp.

  10. Controllable synthesis, magnetic and biocompatible properties of Fe{sub 3}O{sub 4} and {alpha}-Fe{sub 2}O{sub 3} nanocrystals

    SciTech Connect (OSTI)

    Zhou, Xi, E-mail: xizhou@xmu.edu.cn [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China)] [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China); Shi, Yanfeng; Ren, Lei [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China)] [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China); Bao, Shixiong [State Key Laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China)] [State Key Laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Han, Yu; Wu, Shichao; Zhang, Honggang; Zhong, Lubin [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China)] [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China); Zhang, Qiqing, E-mail: zhangqiq@xmu.edu.cn [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China)] [Research Center of Biomedical Engineering, Department of Biomaterials, College of Materials, The Key Laboratory of Biomedical Engineering of Fujian Province, Xiamen University, Xiamen, Fujian 361005 (China)

    2012-12-15T23:59:59.000Z

    Iron oxide nanocrystals (NCs) with a series of well-controlled morphologies (octahedron, rod, wire, cube and plate) and compositions (Fe{sub 3}O{sub 4} and {alpha}-Fe{sub 2}O{sub 3}) were synthesized via a facile hydrothermal process. The morphological and compositional control of various iron oxide NCs was based on the regulations of precursor thermolysis kinetics and surfactants. The obtained samples were characterized by XRD, SEM, TEM, SQUID and cytotoxicity test. These as-prepared iron oxide NCs showed excellent magnetic properties and good biocompatibility, paving the way for their high-efficiency bio-separation and bio-detection applications. - Graphical Abstract: Schematic illustration for the formation of iron oxide NCs (Fe{sub 3}O{sub 4} and {alpha}-Fe{sub 2}O{sub 3}) with different controlled morphologies and compositions. Highlights: Black-Right-Pointing-Pointer Iron oxide NCs with a series of well-controlled morphologies (octahedron, rod, wire, cube, and plate) and compositions (Fe{sub 3}O{sub 4} and {alpha}-Fe{sub 2}O{sub 3}) were synthesized via a facile hydrothermal method. Black-Right-Pointing-Pointer The mechanism of the morphological and compositional control process is directly related to precursor thermolysis kinetics and surfactants. Black-Right-Pointing-Pointer These iron oxide NCs exhibited excellent magnetic response and good biocompatibility, which should have great applications in the cell separation and biodetection.

  11. Interfacial mode coupling as the origin of the enhancement of T<sub>c> in FeSe films on SrTiO<sub>3sub>

    SciTech Connect (OSTI)

    Lee, J.J.; Schmitt, F.T.; Moore, R.G.; Johnston, S.; Cui, Y.-T.; Li, W.; Yi, M.; Liu, Z.K.; Hashimoto, M.; Zhang, Y.; Lu, D.H.; Devereaux, T.P.; Lee, D.-H.; Shen, Z.-X.

    2014-11-12T23:59:59.000Z

    Films of iron selenide (FeSe) one unit cell thick grown on strontium titanate (SrTiO<sub>3sub> or STO) substrates have recently shown superconducting energy gaps opening at temperatures close to the boiling point of liquid nitrogen (77 K), which is a record for the iron-based superconductors. The gap opening temperature usually sets the superconducting transition temperature T<sub>c>, as the gap signals the formation of Cooper pairs, the bound electron states responsible for superconductivity. To understand why Cooper pairs form at such high temperatures, we examine the role of the SrTiO<sub>3sub> substrate. Here we report high-resolution angle-resolved photoemission spectroscopy results that reveal an unexpected characteristic of the single-unit-cell FeSe/SrTiO<sub>3sub> system: shake-off bands suggesting the presence of bosonic modes, most probably oxygen optical phonons in SrTiO<sub>3sub>, which couple to the FeSe electrons with only a small momentum transfer. Such interfacial coupling assists superconductivity in most channels, including those mediated by spin fluctuations. Our calculations suggest that this coupling is responsible for raising the superconducting gap opening temperature in single-unit-cell FeSe/SrTiO<sub>3sub>.

  12. Dielectric, ferromagnetic and maganetoelectric properties of BaTiO{sub 3}–Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4} composite ceramics

    SciTech Connect (OSTI)

    Zhang, Rong-Fen [Department of Electronic Science, College of Science, Key Laboratory of Functional Composite Materials of Guizhou Province, Guizhou University, Guiyang, Guizhou 550025 (China); Deng, Chao-Yong, E-mail: cydeng@gzu.edu.cn [Department of Electronic Science, College of Science, Key Laboratory of Functional Composite Materials of Guizhou Province, Guizhou University, Guiyang, Guizhou 550025 (China); Ren, Li [Department of Electronic Science, College of Science, Key Laboratory of Functional Composite Materials of Guizhou Province, Guizhou University, Guiyang, Guizhou 550025 (China); Li, Zheng [Department of Materials Science and Engineering, State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China); Zhou, Jian-Ping [College of Physics and Information Technology, Shaanxi Normal University, Xi’an 710062 (China)

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • The lead-free ME ceramic composites BaTiO{sub 3}–Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4} were successfully synthesized. • The composites showed high dielectric constant and low dielectric loss. • The composite with 30% NiZn ferrite presented good soft magnetic properties and ME performance. - Abstract: Lead-free magnetoelectric composite ceramics (1 ? x)BaTiO{sub 3}–xNi{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4} (x = 0.15, 0.3, 0.45) were successfully prepared by conventional oxide ceramic process. The tetragonal perovskite BaTiO{sub 3} and cubic spinel Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4} were confirmed by X-ray diffraction. The dielectric behaviors of all composite samples show a normal response to the increasing measurement frequency and Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4} ferrite content. Well defined ferromagnetic hysteresis loops and obvious magnetoelectric coupling effect are observed in the composite ceramics. The influence of applied dc bias magnetic field and Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4} ferrite content on the magnetoelectric coupling responding voltage is investigated. The strongest peak magnetoelectric coupling voltage coefficient is 124 ?V/cm Oe when x = 0.3, which corresponds to the maximum magnetoelectric coupling responding voltage of 200 ?V.

  13. Microdomains, solid solutions and the {open_quotes}defect fluorite{close_quotes} to C-type sesquioxide transition in CeO{sub 2}-RO{sub 1.5} and ZrO{sub 2}-RO{sub 1.5} systems

    SciTech Connect (OSTI)

    Withers, R.L.; Thompson, J.G.; Gabbitas, N.; Wallenburg, L.R.; Welberry, T.R. [Australian National Univ., Canberra (Australia)] [Australian National Univ., Canberra (Australia)

    1995-12-01T23:59:59.000Z

    Satellite dark field (SDF) imaging is used to show that there is a definite change in symmetry on moving across the two phase region separating the so-called {open_quotes}defect fluorite{close_quotes} and C-type sesquioxide solid solution regions in (1-x)CeO{sub 2}.xRO{sub 1.5} and (1-x)ZrO{sub 2}.xRO{sub 1.5} systems. SDF images of the {open_quotes}defect fluorite{close_quotes} side of the two-phase region are characterized by a microdomain texture on the {approximately}100-200 {angstrom} scale and the local symmetry within any one of these microdomains is shown to be lower than cubic. Corresponding SDF images of the C-type sesquioxide side of the two-phase region are by contrast homogeneous and consistent with Ia3 space group symmetry. The nature of the local oxygen vacancy distribution on either side of the two-phase region is discussed and a possible model for the {open_quotes}defect fluorite{close_quotes} side of the two-phase region proposed.

  14. Enhanced dielectric constant and relaxor behavior realized by dual stage sintering of Sr{sub 0.5}Ba{sub 0.5}Nb{sub 2}O{sub 6}

    SciTech Connect (OSTI)

    Rathore, Satyapal S., E-mail: satish.vitta@iitb.ac.in; Vitta, Satish, E-mail: satish.vitta@iitb.ac.in [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai- 400076 (India)

    2014-04-24T23:59:59.000Z

    The relaxor ferroelectric compound, Sr{sub 0.5}Ba{sub 0.5}Nb{sub 2}O{sub 6} (SBN50) was synthesized by solid state reaction followed by sintering under two different conditions: single and dual stage sintering. The impact of sintering process on structural and dielectric properties has been studied in detail using X-ray diffraction, scanning electron microscopy and broadband dielectric spectroscopy. The crystal structure determined by performing Rietveld refinement of X-ray diffractogram was found to be identical in both cases. SBN50 crystallizes in the ferroelectric tetragonal tungsten bronze, P4bm structure. It was observed that uniform grain growth can be controlled by dual stage sintering and relatively narrow distribution of grains can be achieved with an average grain size of ?15 ?m. The dielectric studies show that SBN50 exhibits a relaxor ferroelectric behavior with the transformation taking place at ? 380 K due to formation of polar nano regions. Although both single and dual stage sintered SBN50 exhibits relaxor behaviour, the maximum dielectric constant of dual stage sintered SBN50 is found to be 1550 compare to 1440 for single stage sintering.

  15. Luminescence properties of a blue-emitting phosphor: (Sr{sub 1?x}Eu{sub x})Si{sub 9}Al{sub 19}ON{sub 31} (0

    SciTech Connect (OSTI)

    Liu, Lihong [Structural and Functional Integration of Ceramics Group, The Division of Functional Materials and Nanodevices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201 (China); Xie, Rong-Jun, E-mail: XIE.Rong-Jun@nims.go.jp [Sialon Group, Sialon Unit, National Institute for Materials Science, Namiki 1-1, Tsukuba, Ibaraki 305-0044 (Japan); Hirosaki, Naoto; Dierre, Benjamin [Sialon Group, Sialon Unit, National Institute for Materials Science, Namiki 1-1, Tsukuba, Ibaraki 305-0044 (Japan); Sekiguchi, Takashi [Advanced Electronic Materials Center, National Institute for Materials Science, Namiki 1-1, Tsukuba, Ibaraki 305-0044 (Japan)

    2013-11-15T23:59:59.000Z

    Blue-emitting Sr{sub 1?x}Eu{sub x}Si{sub 9}Al{sub 19}ON{sub 31} phosphors were synthesized at 1800 °C for 2 h under 1 MPa N{sub 2} by using the gas-pressure sintering method (GPS). The microstructure, photoluminescence (PL) properties of the prepared phosphors were investigated. Under the 290 nm excitation, broad PL emission bands with peak positions at 448–490 nm were detected. The concentration quenching was not observed owing to the large distance betweenEu{sup 2+} ions that made the nonradiative energy transfer between neighboring Eu{sup 2+} ions difficult. The blue phosphor generally showed a small thermal quenching at low Eu{sup 2+} concentrations. The absorption and external quantum efficiency of the synthesized Sr{sub 0.5}Eu{sub 0.5}Si{sub 9}Al{sub 19}ON{sub 31} were 85% and 62% upon the 365 nm excitation, respectively. The interesting PL results indicate that Sr{sub 1?x}Eu{sub x}Si{sub 9}Al{sub 19}ON{sub 31} has great potentials as a blue phosphor for white LEDs applications. - Graphical abstract: Sr{sub 0.7}Eu{sub 0.3}Si{sub 9}Al{sub 19}ON{sub 31} gives blue-emitting at 471 nm. Excitation spectrum is composed of five bands in the range of 250–450 nm, which are matching well with emission wavelength of UV LEDs. Display Omitted - Highlights: • Blue-emitting Sr{sub 1?x}Eu{sub x}Si{sub 9}Al{sub 19}ON{sub 31} phosphors were synthesized by gas-pressure sintering method. • The concentration quenching was not observed in this phosphor. • This blue phosphor generally showed a small thermal quenching at low Eu{sup 2+} concentrations. • The absorption and external quantum efficiency of the synthesized Sr{sub 0.5}Eu{sub 0.5}Si{sub 9}Al{sub 19}ON{sub 31} were 85% and 62% upon the 365 nm excitation.

  16. Sub- and above barrier fusion of loosely bound $^6$Li with $^{28}$Si

    E-Print Network [OSTI]

    Mandira Sinha; H. Majumdar; P. Basu; Subinit Roy; R. Bhattacharya; M. Biswas; M. K. Pradhan; R. Palit; I. Mazumdar; S. Kailas

    2010-05-07T23:59:59.000Z

    Fusion excitation functions are measured for the system $^6$Li+$^{28}$Si using the characteristic $\\gamma$-ray method, encompassing both the sub-barrier and above barrier regions, viz., $E_{lab}$= 7-24 MeV. Two separate experiments were performed, one for the above barrier region ($E_{lab}$= 11-24 MeV) and another for the below barrier region ($E_{lab}$= 7-10 MeV). The results were compared with our previously measured fusion cross section for the $^7$Li+$^{28}$Si system. We observed enhancement of fusion cross section at sub-barrier regions for both $^6$Li and $^7$Li, but yield was substantially larger for $^6$Li. However, for well above barrier regions, similar type of suppression was identified for both the systems.

  17. Drift velocity of electrons in quantum wells of selectively doped In{sub 0.5}Ga{sub 0.5}As/Al{sub x}In{sub 1-x}As and In{sub 0.2}Ga{sub 0.8}As/Al{sub x}Ga{sub 1-x}As heterostructures in high electric fields

    SciTech Connect (OSTI)

    Pozela, J., E-mail: pozela@pfi.lt; Pozela, K.; Raguotis, R.; Juciene, V. [Center for Physical Sciences and Technology, Semiconductor Physics Institute (Lithuania)

    2011-06-15T23:59:59.000Z

    The field dependence of drift velocity of electrons in quantum wells of selectively doped In{sub 0.5}Ga{sub 0.5}As/Al{sub x}In{sub 1-x}As and In{sub 0.2}Ga{sub 0.8}As/Al{sub x}Ga{sub 1-x}As heterostructures is calculated by the Monte Carlo method. The influence of varying the molar fraction of Al in the composition of the Al{sub x}Ga{sub 1-x}As and Al{sub x}In{sub 1-x}As barriers of the quantum well on the mobility and drift velocity of electrons in high electric fields is studied. It is shown that the electron mobility rises as the fraction x of Al in the barrier composition is decreased. The maximum mobility in the In{sub 0.5}Ga{sub 0.5}As/In{sub 0.8}Al{sub 0.2}As quantum wells exceeds the mobility in a bulk material by a factor of 3. An increase in fraction x of Al in the barrier leads to an increase in the threshold field E{sub th} of intervalley transfer (the Gunn effect). The threshold field is E{sub th} = 16 kV/cm in the In{sub 0.5}Ga{sub 0.5}As/Al{sub 0.5}In{sub 0.5}As heterostructures and E{sub th} = 10 kV/cm in the In{sub 0.2}Ga{sub 0.8}As/Al{sub 0.3}Ga{sub 0.7}As heterostructures. In the heterostructures with the lowest electron mobility, E{sub th} = 2-3 kV/cm, which is lower than E{sub th} = 4 kV/cm in bulk InGaAs.

  18. Crystal structure of the binary complex of cobalt and zinc chlorides with carbamide [Co(OCN{sub 2}H{sub 4}){sub 5}(H{sub 2}O)][ZnCl{sub 4}

    SciTech Connect (OSTI)

    Furmanova, N. G., E-mail: furm@ns.crys.ras.ru; Chernaya, T. S. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Resnyanskii, V. F., E-mail: kakin@inbox.ru; Sulaimankulov, K. S. [National Academy of Sciences of Kyrgyzstan, Institute of Chemistry and Chemical Technology (Kyrgyzstan)

    2010-03-15T23:59:59.000Z

    Mixed single crystals of [Co(OCN{sub 2}H{sub 4}){sub 5}(H{sub 2}O)][ZnCl{sub 4}] were grown by the isothermal evaporation of an aqueous solution. The crystal structure of this complex was established by X-ray diffraction (R = 0.052 based on 7003 reflections). The crystals consist of [Co(OCN{sub 2}H{sub 4}){sub 5}(H{sub 2}O)]{sup 2+} cations containing Co atoms in an octahedral coordination and [ZnCl{sub 4}]{sup 2-}] anions containing Zn atoms in a tetrahedral coordination. The carbamide molecules are involved in both intramolecular and interionic hydrogen bonds. The H{sub 2}O molecule forms hydrogen bonds with the anions.

  19. Temperature driven transition from giant to tunneling magneto-resistance in Fe{sub 3}O{sub 4}/Alq{sub 3}/Co spin Valve: Role of Verwey transition of Fe{sub 3}O{sub 4}

    SciTech Connect (OSTI)

    Dey, P., E-mail: pujaiitkgp2007@gmail.com; Rawat, R.; Potdar, S. R.; Choudhary, R. J.; Banerjee, A. [UGC-DAE Consortium for Scientific Research (CSR), University Campus, Khandwa Road, Indore 452 001 (India)

    2014-05-07T23:59:59.000Z

    We demonstrate interface energy level engineering, exploiting the modification in energy band structure across Verwey transition temperature (T{sub V}) of Fe{sub 3}O{sub 4}, in a Fe{sub 3}O{sub 4}(111)/Alq{sub 3}/Co spin-valve (SV). I-V characteristics exhibit a transition in conduction mode from carrier injection to tunneling across T{sub V} of Fe{sub 3}O{sub 4} electrode. Both giant magneto-resistance (GMR) and tunneling MR (TMR) have been observed in a single SV, below and above T{sub V}, respectively. We have achieved room-temperature SV operation in our device. We believe that the tuning of charge gap at Fermi level across T{sub V} resulting in a corresponding tuning of conduction mode and a unique cross over from GMR to TMR.

  20. Electron beam induced oxygen in YBa sub 2 Cu sub 3 O sub 7-x superconductors

    SciTech Connect (OSTI)

    Basu, S.N.; Roy, T.; Mitchell, T.E.; Nastasi, M.

    1989-01-01T23:59:59.000Z

    Thin foils of bulk YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) superconductors were subjected to electron irradiation in a Transmission Electron Microscope (TEM). The resulting disordering of the oxygen atoms and vacancies in the Cu-O planes was monitored by measuring the splitting of the (110) diffraction spots in the (001) diffraction pattern. Samples were irradiated at 83K with 100, 150, 200 and 300kV electrons. The 100kV electrons did not cause any disordering, even after prolonged irradiation. The results of the higher energy irradiations showed an excellent fit to a disordering model, indicating a lack of radiation assisted ordering at 83K. This was further confirmed by the insensitivity of the disordering to the dose rate of 300kV electrons at 83K. However, at 300K, an increase in the dose rate of 300kV electrons increased the disordering rate, indicating that radiation assisted reordering was occurring at that temperature. 7 refs., 4 figs.

  1. Measurement of Muon Antineutrino Quasielastic Scattering on a Hydrocarbon Target at E<sub>?>~3.5 GeV

    SciTech Connect (OSTI)

    Fields, L.; Chvojka, J.; Aliaga, L.; Altinok, O.; Baldin, B.; Baumbaugh, A.; Bodek, A.; Boehnlein, D.; Boyd, S.; Bradford, R.; Brooks, W. K.; Budd, H.; Butkevich, A.; Martinez Caicedo, D. A.; Castromonte, C. M.; Christy, M. E.; Chung, H.; Clark, M.; da Motta, H.; Damiani, D. S.; Danko, I.; Datta, M.; Day, M.; DeMaat, R.; Devan, J.; Draeger, E.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Edmondson, D. A.; Felix, J.; Fitzpatrick, T.; Fiorentini, G. A.; Gago, A. M.; Gallagher, H.; George, C. A.; Gielata, J. A.; Gingu, C.; Gobbi, B.; Gran, R.; Grossman, N.; Hanson, J.; Harris, D. A.; Heaton, J.; Higuera, A.; Howley, I. J.; Hurtado, K.; Jerkins, M.; Kafka, T.; Kaisen, J.; Kanter, M. O.; Keppel, C. E.; Kilmer, J.; Kordosky, M.; Krajeski, A. H.; Kulagin, S. A.; Le, T.; Lee, H.; Leister, A. G.; Locke, G.; Maggi, G.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Niculescu, G.; Niculescu, I.; Ochoa, N.; O’Connor, C. D.; Olsen, J.; Osmanov, B.; Osta, J.; Palomino, J. L.; Paolone, V.; Park, J.; Patrick, C. E.; Perdue, G. N.; Peña, C.; Rakotondravohitra, L.; Ransome, R. D.; Ray, H.; Ren, L.; Rodrigues, P. A.; Rude, C.; Sassin, K. E.; Schellman, H.; Schmitz, D. W.; Schneider, R. M.; Schulte, E. C.; Simon, C.; Snider, F. D.; Snyder, M. C.; Sobczyk, J. T.; Solano Salinas, C. J.; Tagg, N.; Tan, W.; Tice, B. G.; Tzanakos, G.; Velásquez, J. P.; Walding, J.; Walton, T.; Wolcott, J.; Wolthuis, B. A.; Woodward, N.; Zavala, G.; Zeng, H. B.; Zhang, D.; Zhu, L. Y.; Ziemer, B. P.

    2013-07-01T23:59:59.000Z

    We have isolated ?¯<sub>?> charged-current quasielastic (QE) interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross section, d?/dQ², and compare to several theoretical models of QE scattering. Good agreement is obtained with a model where the nucleon axial mass, M<sub>A>, is set to 0.99 GeV/c² but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q² favor this interpretation over an alternative in which the axial mass is increased.

  2. THE EFFECT OF A TWISTED MAGNETIC FIELD ON THE PERIOD RATIO P{sub 1}/P{sub 2} OF NONAXISYMMETRIC MAGNETOHYDRODYNAMIC WAVES

    SciTech Connect (OSTI)

    Karami, K. [Department of Physics, University of Kurdistan, Pasdaran Street, Sanandaj (Iran, Islamic Republic of); Bahari, K., E-mail: KKarami@uok.ac.ir, E-mail: K.Bahari@razi.ac.ir [Physics Department, Faculty of Science, Razi University, Kermanshah (Iran, Islamic Republic of)

    2012-10-01T23:59:59.000Z

    We consider nonaxisymmetric magnetohydrodynamic (MHD) modes in a zero-beta cylindrical compressible thin magnetic flux tube modeled as a twisted core surrounded by a magnetically twisted annulus, with both embedded in a straight ambient external field. The dispersion relation is derived and solved analytically and numerically to obtain the frequencies of the nonaxisymmetric MHD waves. The main result is that the twisted magnetic annulus does affect the period ratio P{sub 1}/P{sub 2} of the kink modes. For the kink modes, the magnetic twist in the annulus region can achieve deviations from P{sub 1}/P{sub 2} = 2 of the same order of magnitude as in the observations. Furthermore, the effect of the internal twist on the fluting modes is investigated.

  3. Microsoft Word - IGCA Inventory Sub Guide 031611 | Department...

    Office of Environmental Management (EM)

    Word - IGCA Inventory Sub Guide 031611 Microsoft Word - IGCA Inventory Sub Guide 031611 Microsoft Word - IGCA Inventory Sub Guide 031611 More Documents & Publications OFFICE OF...

  4. IGCA Inventory Sub Guide 040512 | Department of Energy

    Energy Savers [EERE]

    Inventory Sub Guide 040512 IGCA Inventory Sub Guide 040512 IGCAInventorySubGuide040512.pdf More Documents & Publications OFFICE OF PROCUREMENT & ASSISTANCE MANAGEMENT...

  5. Northwest Regional Technology Center

    E-Print Network [OSTI]

    Northwest Regional Technology Center for Homeland Security The Northwest Regional Technology Center and deployment of technologies that are effective homeland security solutions for the region, and accelerate technology transfer to the national user community. Foster a collaborative spirit across agencies

  6. Cathode encapsulation of organic light emitting diodes by atomic layer deposited Al{sub 2}O{sub 3} films and Al{sub 2}O{sub 3}/a-SiN{sub x}:H stacks

    SciTech Connect (OSTI)

    Keuning, W.; Weijer, P. van de; Lifka, H.; Kessels, W. M. M.; Creatore, M. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Philips Research Laboratories, High Tech Campus 4, P.O. Box WAG12, 5656 AE Eindhoven (Netherlands); Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

    2012-01-15T23:59:59.000Z

    Al{sub 2}O{sub 3} thin films synthesized by plasma-enhanced atomic layer deposition (ALD) at room temperature (25 deg. C) have been tested as water vapor permeation barriers for organic light emitting diode devices. Silicon nitride films (a-SiN{sub x}:H) deposited by plasma-enhanced chemical vapor deposition served as reference and were used to develop Al{sub 2}O{sub 3}/a-SiN{sub x}:H stacks. On the basis of Ca test measurements, a very low intrinsic water vapor transmission rate of {<=} 2 x 10{sup -6} g m{sup -2} day{sup -1} and 4 x 10{sup -6} g m{sup -2} day{sup -1} (20 deg. C/50% relative humidity) were found for 20-40 nm Al{sub 2}O{sub 3} and 300 nm a-SiN{sub x}:H films, respectively. The cathode particle coverage was a factor of 4 better for the Al{sub 2}O{sub 3} films compared to the a-SiN{sub x}:H films and an average of 0.12 defects per cm{sup 2} was obtained for a stack consisting of three barrier layers (Al{sub 2}O{sub 3}/a-SiN{sub x}:H/Al{sub 2}O{sub 3}).

  7. Synthesis of Li{sub (x)}Na{sub (2-x)}Mn{sub 2}S{sub 3} and LiNaMnS{sub 2} through redox-induced ion exchange reactions

    SciTech Connect (OSTI)

    Luthy, Joshua A.; Goodman, Phillip L. [Department of Chemistry and Biochemistry, Texas State University-San Marcos, 601 University Drive, San Marcos, TX 78666 (United States); Martin, Benjamin R. [Department of Chemistry and Biochemistry, Texas State University-San Marcos, 601 University Drive, San Marcos, TX 78666 (United States)], E-mail: bmartin@txstate.edu

    2009-03-15T23:59:59.000Z

    Na{sub 2}Mn{sub 2}S{sub 3} was oxidatively deintercalated using iodine in acetonitrile to yield Na{sub 1.3}Mn{sub 2}S{sub 3}, with lattice constants nearly identical to that of the reactant. Lithium was then reductively intercalated into the oxidized product to yield Li{sub 0.7}Na{sub 1.3}Mn{sub 2}S{sub 3}. When heated, this metastable compound decomposed to form a new crystalline compound, LiNaMnS{sub 2}, along with MnS and residual Na{sub 2}Mn{sub 2}S{sub 3}. Single crystal X-ray diffraction structural analysis of LiNaMnS{sub 2} revealed that this compound crystallizes in P-3m1 with cell parameters a=4.0479(6) A, c=6.7759(14) A, V=96.15(3) A{sup 3} (Z=1, wR2=0.0367) in the NaLiCdS{sub 2} structure-type. - Graphical abstract: Structure of LiNaMnS{sub 2}. Li and Mn are statistically distributed in edge-shared tetrahedral environments linked into infinite planes. Sodium ions occupy interlayer sites.

  8. Process for separation of CO/sub 2/ from CO/sub 2/-containing gases

    SciTech Connect (OSTI)

    Linde, G.

    1985-07-09T23:59:59.000Z

    For separating CO/sub 2/ from CO/sub 2/-containing gases, especially stack gases and/or blast furnace gases, dimethylformamide is employed as a physical scrubbing medium to ensure high CO/sub 2/ purity. After absorption of CO/sub 2/, the DMF is regenerated and returned into the scrubbing stage. Dimethylformamide is utilized as the scrubbing medium.

  9. Electronic and optical properties of the cubic spinel phase of c-Si{sub 3}N{sub 4}, c-Ge{sub 3}N{sub 4}, c-SiGe{sub 2}N{sub 4}, and c-GeSi{sub 2}N{sub 4}

    SciTech Connect (OSTI)

    Ching, W. Y.; Mo, Shang-Di; Ouyang, Lizhi

    2001-06-15T23:59:59.000Z

    The electronic and optical properties of the new cubic spinel nitrides c-Si{sub 3}N{sub 4}, c-Ge{sub 3}N{sub 4}, and that of the predicted double nitrides c-SiGe{sub 2}N{sub 4} and c-GeSi{sub 2}N{sub 4} are studied by a first-principles method. They are all semiconductors with band gaps between 1.85 and 3.45 eV and a bulk modulus between 258 and 280 GPa. From the total-energy calculations, it is shown that c-SiGe{sub 2}N{sub 4} should be a stable compound while c-GeSi{sub 2}N{sub 4} could be metastable. The compound c-SiGe{sub 2}N{sub 4} is of particular interest because of a favorable direct band gap of 1.85 eV and a conduction-band effective mass of 0.49. The crystal has a very strong covalent bonding character as revealed by the calculated Mulliken effective charge and bond order. The strong covalent bonding in c-SiGe{sub 2}N{sub 4} is attributed to the optimal arrangement of the cations. The smaller Si ion occupies the tetrahedrally coordinated (8a) site and the larger Ge ion occupies the octahedrally coordinated (16d) site.

  10. Positron annihilation studies of the AlO{sub x}/SiO{sub 2}/Si interface in solar cell structures

    SciTech Connect (OSTI)

    Edwardson, C. J.; Coleman, P. G. [Department of Physics, University of Bath, Bath BA2 7AY (United Kingdom); Li, T.-T. A.; Cuevas, A. [College of Engineering and Computer Science, Australian National University, Canberra, ACT 0200 (Australia); Ruffell, S. [Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2012-03-01T23:59:59.000Z

    Film and film/substrate interface characteristics of 30 and 60 nm-thick AlO{sub x} films grown on Si substrates by thermal atomic layer deposition (ALD), and 30 nm-thick AlO{sub x} films by sputtering, have been probed using variable-energy positron annihilation spectroscopy (VEPAS) and Doppler-broadened spectra ratio curves. All samples were found to have an interface which traps positrons, with annealing increasing this trapping response, regardless of growth method. Thermal ALD creates an AlO{sub x}/SiO{sub x}/Si interface with positron trapping and annihilation occurring in the Si side of the SiO{sub x}/Si boundary. An induced positive charge in the Si next to the interface reduces diffusion into the oxides and increases annihilation in the Si. In this region there is a divacancy-type response (20 {+-} 2%) before annealing which is increased to 47 {+-} 2% after annealing. Sputtering seems to not produce samples with this same electrostatic shielding; instead, positron trapping occurs directly in the SiO{sub x} interface in the as-deposited sample, and the positron response to it increases after annealing as an SiO{sub 2} layer is formed. Annealing the film has the effect of lowering the film oxygen response in all film types. Compared to other structural characterization techniques, VEPAS shows larger sensitivity to differences in film preparation method and between as-deposited and annealed samples.

  11. Structural studies of the metal-rich region in the ternary Ta-Nb-S system

    SciTech Connect (OSTI)

    Yao, Xiaoqiang.

    1991-10-07T23:59:59.000Z

    Six new solid solution type compounds have been prepared using high temperature techniques and characterized by means of single crystal x-ray techniques during a study of the metal-rich region of the ternary Ta-Nb-S system. The structures of Nb{sub x}Ta{sub 11-x}S{sub 4} are reminiscent of niobium-rich sulfides, rather than of tantalum-rich sulfides. The coordinations of sulfur are capped trigonal prismatic while the metal coordinations are capped distorted cubic prismatic for Nb{sub x}Ta{sub 11-x}S{sub 4}, and capped distorted cubic prismatic and pentagonal prismatic for Nb{sub 12-x}Ta{sub x}S{sub 4}. The structures of Nb{sub x}Ta{sub 5-x}S{sub 2} contain homoatomic layers sequenced S-M3-M2-M1-M2-M3-S (M is mixed Nb, Ta) generating six-layer sheets, respectively. Weak S-S interactions at 3.26 and 3.19{Angstrom} between sheets contrast with the M-M binding within and between the sheets in these two novel layered compounds. The former are presumably responsible for the observed graphitic slippage of the samples. Nb{sub 21-x}Ta{sub x}S{sub 8} and Nb{sub x}Ta{sub 2-x}S are isostructural with Nb{sub 21}S{sub 8} and Ta{sub 2}S, respectively. Extended Hueckel band calculations were carried out for two layered compounds, Nb{sub x}Ta{sub 5-x}S{sub 2} (x {approx} 1.72) and Nb{sub x}ta{sub 2-x}S (x {approx} 0.95). Based upon band calculations metallic properties can be expected for these two layered compounds. The relative preference of the metal sites for the two metal elements (Ta, Nb) in two layered compounds is explained by the results of the band calculations. 17 figs., 31 tabs., 80 refs.

  12. Formation of mixed oxide powders in flames: Part II. SiO sub 2 --GeO sub 2 and Al sub 2 O sub 3 --TiO sub 2

    SciTech Connect (OSTI)

    Hung, C.; Miquel, P.F.; Katz, J.L. (Department of Chemical Engineering, The Johns Hopkins University, Baltimore, Maryland 21218 (United States))

    1992-07-01T23:59:59.000Z

    SiO{sub 2}--GeO{sub 2} and Al{sub 2}O{sub 3}--TiO{sub 2} mixed oxide powders were synthesized using a counterflow diffusion flame burner. SiCl{sub 4}, GeCl{sub 4}, Al(CH{sub 3}){sub 3}, and TiCl{sub 4} were used as source materials for the formation of oxide particles in hydrogen-oxygen flames. {ital In} {ital situ} particle sizes were determined using dynamic light-scattering. Powders were collected using two different methods, a thermophoretic method (particles are collected onto carbon coated TEM grids) and an electrophoretic method (particles are collected onto stainless steel strips). Their size, morphology, and crystalline form were examined using a transmission electron microscope and an x-ray diffractometer. A photomultiplier at 90{degree} to the argon ion laser beam was used to measure the light-scattering intensity. The formation of the mixed oxides was investigated using Si to Ge and Al to Ti ratios of 3:5 and 1:1, respectively. Heterogeneous nucleation of the SiO{sub 2} on the surface of the GeO{sub 2} was observed. In Al{sub 2}O{sub 3}--TiO{sub 2} mixtures, both oxide particles form at the same temperature. X-ray diffraction analysis of particles sampled at temperatures higher than 1553 K showed the presence of rutile, {gamma}--Al{sub 2}O{sub 3}, and aluminum titanate. Although the particle formation processes for SiO{sub 2}--GeO{sub 2} is very different from that for Al{sub 2}O{sub 3}--TiO{sub 2}, both mixed oxides result in very uniform mixtures.

  13. Photocatalytic oxidation of NO{sub x} using TiO{sub 2}/activated carbon

    SciTech Connect (OSTI)

    Wang, S.; Chen, D.H.; Li, K.Y. [Lamar Univ., Beaumont, TX (United States)] [and others

    1995-12-31T23:59:59.000Z

    This paper summarizes experimental results for a method of nitrogen oxides (NO{sub x}) emission control. NO{sub x} was oxidized photocatalytically to nitric acid (HNO{sub 3}) using different titanium dioxide (TiO{sub 2}) catalysts. The addition of ferric oxide improved the performance of the TiO{sub 2}. Of four adsorbents tested, activated carbon performed best in suppressing NO{sub 2} concentration. Optimum catalyst compositions were determined. Initial results indicated that photocatalytic oxidation of NO{sub x} offers several advantages over other emission control methods.

  14. Synthesis and crystal structure of a new open-framework iron phosphate (NH{sub 4}){sub 4}Fe{sub 3}(OH){sub 2}F{sub 2}[H{sub 3}(PO{sub 4}){sub 4}]: Novel linear trimer of corner-sharing Fe(III) octahedra

    SciTech Connect (OSTI)

    Mi, Jin-Xiao, E-mail: jxmi@xmu.edu.c [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Wang, Cheng-Xin [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Chen, Ning [Canadian Light Source, University of Saskatchewan, Saskatoon, SK, Canada S7N 0X4 (Canada); Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E2 (Canada); Li, Rong [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E2 (Canada); Pan, Yuanming [Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E2 (Canada)

    2010-12-15T23:59:59.000Z

    A new iron phosphate (NH{sub 4}){sub 4}Fe{sub 3}(OH){sub 2}F{sub 2}[H{sub 3}(PO{sub 4}){sub 4}] has been synthesized hydrothermally at HF concentrations from 0.5 to 1.2 mL. Single-crystal X-ray diffraction analysis reveals its three-dimensional open-framework structure (monoclinic, space group P2{sub 1}/n (No. 14), a=6.2614(13) A, b=9.844(2) A, c=14.271(3) A, {beta}=92.11(1){sup o}, V=879.0(3) A{sup 3}). This structure is built from isolated linear trimers of corner-sharing Fe(III) octahedra, which are linked by (PO{sub 4}) groups to form ten-membered-ring channels along [1 0 0]. This isolated, linear trimer of corner-sharing Fe(III) octahedra, [(FeO{sub 4}){sub 3}(OH){sub 2}F{sub 2}], is new and adds to the diverse linkages of Fe polyhedra as secondary building units in iron phosphates. The trivalent iron at octahedral sites for the title compound has been confirmed by synchrotron Fe K-edge XANES spectra and magnetic measurements. Magnetic measurements also show that this compound exhibit a strong antiferromagnetic exchange below T{sub N}=17 K, consistent with superexchange interactions expected for the linear trimer of ferric octahedra with the Fe-F-Fe angle of 132.5{sup o}. -- Graphical abstract: The three-dimensional open-framework structure of (NH{sub 4}){sub 4}Fe{sub 3}(OH){sub 2}F{sub 2}[H{sub 3}(PO{sub 4}){sub 4}] is built from a novel isolated, linear (FeO{sub 4}){sub 3}(OH){sub 2}F{sub 2} trimer of corner-sharing Fe(III) octahedra linked by PO{sub 4} tetrahedra. Display Omitted

  15. Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub T} in Au+Au collisions at {radical}s{sub NN} = 130 GeV

    SciTech Connect (OSTI)

    Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B.D.; Arkhipkin, D.; Averichev, G.S.; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellwied, R.; Berger, J.; Bezverkhny, B.I.; Bharadwaj, S.; Bhatia, V.S.; Bichsel, H.; Billmeier, A.; Bland, L.C.; Blyth, C.O.; Bonner, B.E.; Botje, M.; Boucham, A.; Brandin, A.; Bravar, A.; Bystersky, M.; Cadman, R.V.; Cai, X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Carroll, J.; Castillo, J.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, H.F.; Chen, Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Cramer, J.G.; Crawford, H.J.; Das, D.; Das, S.; de Moura, M.M.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Dong, W.J.; Dong, X.; Draper, J.E.; Du, F.; Dubey, A.K.; Dunin, V.B.; Dunlop, J.C.; Dutta Mazumdar, M.R.; Eckardt, V.; Edwards, W.R.; Efimov, L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Faivre, J.; Fatemi, R.; Fedorisin, J.; Filimonov, K.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Foley, K.J.; Fomenko, K.; Fu, J.; Gagliardi, C.A.; Gans, J.; Ganti, M.S.; Gaudichet, L.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.E.; Grachov, O.; Grebenyuk, O.; Grosnick, D.; Guertin, S.M.; Gupta, A.; Gutierrez, T.D.; Hallman, T.J.; Hamed, A.; Hardtke, D.; Harris, J.W.; Heinz, M.; Henry, T.W.; Heppelmann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G.W.; Huang, H.Z.; Huang, S.L.; Hughes, E.W.; Humanic, T.J.; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, W.W.; Janik, M.; Jiang, H.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kang, K.; Kaplan, M.; Keane, D.; Khodyrev, V.Yu; Kiryluk, J.; Kisiel, A.; Kislov, E.M.; Klay, J.; Klein, S.R.; Klyachko, A.; Koetke, D.D.; Kollegger, T.; Kopytine, M.; Kotchenda, L.; Kramer, M.; Kravtsov, P.; Kravtsov, V.I.; Krueger, K.; Kuhn, C.; Kulikov, A.I.; Kumar, A.; Kunz, C.L.; Kutuev, R.Kh.; Kuznetsov, A.A.; Lamont, M.A.C.; et al.

    2004-04-15T23:59:59.000Z

    We present STAR measurements of charged hadron production as a function of centrality in Au + Au collisions at {radical}s{sub NN} = 130 GeV. The measurements cover a phase space region of 0.2 < p{sub T} < 6.0 GeV/c in transverse momentum and -1 < {eta} < 1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5 < |{eta}| < 1 are reported and compared to our previously published results for |{eta}| < 0.5. No significant difference is seen for inclusive p{sub T} distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d{eta} distributions and truncated mean p{sub T} in a region of p{sub T} > p{sub T}{sup cut}, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured p{sub T} region. The relative importance of hard scattering process is investigated through binary scaling fraction of particle production.

  16. Nanocrystalline Cs{sub x}WO{sub 3} particles: Effects of N{sub 2} annealing on microstructure and near-infrared shielding characteristics

    SciTech Connect (OSTI)

    Liu, Jing-Xiao, E-mail: drliu-shi@dlpu.edu.cn [School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034 (China); Institute of Multidisciplinary Research for Advanced Material, Tohoku University, Sendai, 980-8577,Japan (Japan); Shi, Fei; Dong, Xiao-Li; Xu, Qiang [School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034 (China); Yin, Shu; Sato, Tsugio [Institute of Multidisciplinary Research for Advanced Material, Tohoku University, Sendai, 980-8577,Japan (Japan)

    2013-10-15T23:59:59.000Z

    In order to further improve the near-infrared shielding properties of cesium tungsten bronze (Cs{sub x}WO{sub 3}) for solar filter applications, Cs{sub x}WO{sub 3} particles were prepared by solvothermal reaction method and the effects of nitrogen annealing on the microstructure and near-infrared shielding properties of Cs{sub x}WO{sub 3} were investigated. The obtained Cs{sub x}WO{sub 3} samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and spectrophotometer. The results indicate that nanosheet-like Cs{sub x}WO{sub 3} particles with hexagonal structure began to transform into nanorods after annealed at temperature higher than 600 °C. The near-infrared shielding properties of Cs{sub x}WO{sub 3} particles could be further improved by N{sub 2} annealing at 500–700 °C. Particularly, the 500 °C-annealed Cs{sub x}WO{sub 3} samples in the N{sub 2} atmosphere showed best near-infrared shielding properties. It was suggested that the excellent near-infrared shielding ability of the 500 °C-annealed Cs{sub x}WO{sub 3} samples is correlated with its minimum O/W atomic ratio and most oxygen vacancies. Highlights: • N{sub 2} annealing could further improve the near-infrared (NIR) shielding of Cs{sub x}WO{sub 3}. • Effects of N{sub 2} annealing on microstructure and NIR shielding of Cs{sub x}WO{sub 3} were studied. • The 500 °C-N{sub 2}-annealed Cs{sub x}WO{sub 3} exhibited minimum O/W ratio and most oxygen vacancies. • The 500 °C-N{sub 2}-annealed Cs{sub x}WO{sub 3} particles exhibited best NIR shielding properties.

  17. Comparative study of water reactivity with Mo{sub 2}O{sub y}{sup ?} and W{sub 2}O{sub y}{sup ?} clusters: A combined experimental and theoretical investigation

    SciTech Connect (OSTI)

    Ray, Manisha; Waller, Sarah E.; Saha, Arjun; Raghavachari, Krishnan; Jarrold, Caroline Chick, E-mail: cjarrold@indiana.edu [Department of Chemistry, Indiana University, Bloomington, Indiana 47405 (United States)

    2014-09-14T23:59:59.000Z

    A computational investigation of the Mo{sub 2}O{sub y}{sup ?} + H{sub 2}O (y = 4, 5) reactions as well as a photoelectron spectroscopic probe of the deuterated Mo{sub 2}O{sub 6}D{sub 2}{sup ?} product have been carried out to understand a puzzling question from a previous study: Why is the rate constant determined for the Mo{sub 2}O{sub 5}{sup ?} + H{sub 2}O/D{sub 2}O reaction, the terminal reaction in the sequential oxidation of Mo{sub 2}O{sub y}{sup ?} by water, higher than the W{sub 2}O{sub 5}{sup ?} + H{sub 2}O/D{sub 2}O reaction? This disparity was intriguing because W{sub 3}O{sub y}{sup ?} clusters were found to be more reactive toward water than their Mo{sub 3}O{sub y}{sup ?} analogs. A comparison of molecular structures reveals that the lowest energy structure of Mo{sub 2}O{sub 5}{sup ?} provides a less hindered water addition site than the W{sub 2}O{sub 5}{sup ?} ground state structure. Several modes of water addition to the most stable molecular and electronic structures of Mo{sub 2}O{sub 4}{sup ?} and Mo{sub 2}O{sub 5}{sup ?} were explored computationally. The various modes are discussed and compared with previous computational studies on W{sub 2}O{sub y}{sup ?} + H{sub 2}O reactions. Calculated free energy reaction profiles show lower barriers for the initial Mo{sub 2}O{sub y}{sup ?} + H{sub 2}O addition, consistent with the higher observed rate constant. The terminal Mo{sub 2}O{sub y}{sup ?} sequential oxidation product predicted computationally was verified by the anion photoelectron spectrum of Mo{sub 2}O{sub 6}D{sub 2}{sup ?}. Based on the computational results, this anion is a trapped dihydroxide intermediate in the Mo{sub 2}O{sub 5}{sup ?} + H{sub 2}O/D{sub 2}O ? Mo{sub 2}O{sub 6}{sup ?} + H{sub 2}/D{sub 2} reaction.

  18. Activated Al/Al{sub 2}O{sub 3} for transformation of chlorinated hydrocarbons

    SciTech Connect (OSTI)

    Lien, H.L.; Zhang, W.X.

    1999-07-01T23:59:59.000Z

    A method for the preparation of activated Al/Al{sub 2}O{sub 3} mixture has been developed in the laboratory. Al and Al{sub 2}O{sub 3} are infused and activated within an alkaline solution. Optimal Al to Al{sub 2}O{sub 3} ratio is in the range of 0.1 to 1. Batch experiments have demonstrated that the activated Al/Al{sub 2}O{sub 3} mixture can rapidly dechlorinate tetrachloroethylene (PCE), carbon tetrachloride (CT) and hexachlorobenzene (HCB). Due to the high reactivity, light density and low cost, the activated Al/Al{sub 2}O{sub 3} may be used as a remediation agent in ex-situ treatment of industrial effluent, in-situ treatment wall, and for direct injection into ground water.

  19. Vapor-liquid equilibrium of the Mg(NO/sub 3/)/sub 2/-HNO/sub 3/-H/sub 2/O system

    SciTech Connect (OSTI)

    Thompson, B.E.; Derby, J.J.; Stalzer, E.H.

    1983-06-01T23:59:59.000Z

    The vapor-liquid equilibrium of the Mg(NO/sub 3/)/sub 2/-HNO/sub 3/-H/sub 2/O system in concentrations of 0 to 70 wt % Mg(NO/sub 3/)/sub 2/ and 0 to 75 wt % HNO/sub 3/ at atmospheric pressure was correlated by two approaches. One was based on a dissociation equilibrium expression in which the activities of the reacting species (HNO/sub 3/, NO/sub 3//sup -/, and H/sup +/) were approximated with mole fractions. The activity coefficients of the undissociated HNO/sub 3/ and H/sub 2/O were correlated as functions of the concentrations of magnesium nitrate and nitric acid by second-order polynomials. The average absolute difference between predicted and experimental values was 8% for the mole fraction of acid in the vapor and 8/sup 0/K for the bubble-point temperature. The second approach was to correlate the mean ionic rational activity coefficient of water with a form of the excess Gibbs energy composed of two terms. One term, a function of the ionic strength, accounts for the coulombic (ionic) interactions; the other term accounts for the non-coulombic (molecular) interactions. The average absolute difference between predicted and experimental values was 9% for the mole fraction of acid in the vapor, and 10/sup 0/K for the bubble-point temperature.

  20. Observation of spectral composition and polarization of sub-terahertz emission from dense plasma during relativistic electron beam–plasma interaction

    SciTech Connect (OSTI)

    Arzhannikov, A. V.; Burmasov, V. S.; Ivanov, I. A.; Kuznetsov, S. A.; Postupaev, V. V.; Sinitsky, S. L.; Vyacheslavov, L. N. [Budker Institute of Nuclear Physics, 11 Lavrentiev Ave., Novosibirsk 630090 (Russian Federation); Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090 (Russian Federation); Burdakov, A. V. [Budker Institute of Nuclear Physics, 11 Lavrentiev Ave., Novosibirsk 630090 (Russian Federation); Novosibirsk State Technical University, 20 Karl Marks Ave., Novosibirsk 630092 (Russian Federation); Gavrilenko, D. E.; Kasatov, A. A.; Mekler, K. I.; Rovenskikh, A. F. [Budker Institute of Nuclear Physics, 11 Lavrentiev Ave., Novosibirsk 630090 (Russian Federation); Polosatkin, S. V.; Sklyarov, V. F. [Budker Institute of Nuclear Physics, 11 Lavrentiev Ave., Novosibirsk 630090 (Russian Federation); Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090 (Russian Federation); Novosibirsk State Technical University, 20 Karl Marks Ave., Novosibirsk 630092 (Russian Federation)

    2014-08-15T23:59:59.000Z

    The paper presents results of measurements of sub-terahertz electromagnetic emission from magnetized plasma during injection of a powerful relativistic electron beam of microsecond duration in plasma with the density of 3?×?10{sup 14?}cm{sup ?3}. It was found that the spectrum of the radiation concentrated in three distinct regions with high level of spectral power density. The first region is located near f{sub 1}?=?100?GHz; the second one is in the vicinity of 190?GHz, and the third region is in the frequency interval f{sub 3}?=?280–340?GHz. Polarization vectors of the emission in the first and third regions (f{sub 1} and f{sub 3}) are directed mainly perpendicular to the magnetic field in the plasma. At the same time, the polarization of the radiation in the vicinity of f{sub 2}?=?190?GHz is parallel to the magnetic field. The most likely mechanism of electromagnetic wave generation in the frequency regions f{sub 1} and f{sub 2} is the linear conversion of the plasma oscillations into the electromagnetic waves on strong gradients of the plasma density. The third region is situated in the vicinity of second harmonic of electron plasma frequency, and we explain this emission by the coalescence of the upper-hybrid oscillations at high level turbulence in plasma.

  1. Sandia Energy - SubTER

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > TheNuclear PressLaboratorySoftware Home Climate &SubTER Home

  2. Comparison of the crystal and electronic structures of three 2:1 salts of the organic donor molecule BEDT-TTF with pentafluorothiomethylsulfonate anions SF{sub 5}CH{sub 2}SO{sub 3}{sup {minus}}, SF{sub 5}CHFSO{sub 3}{sup {minus}}, and SF{sub 5}CF{sub 2}SO{sub 3}{sup {minus}}

    SciTech Connect (OSTI)

    Ward, B.H.; Schlueter, J.A.; Geiser, U. [and others] [and others

    2000-02-01T23:59:59.000Z

    Salts of the donor molecule, bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF or ET), with pentafluorothiomethylsulfonate (SF{sub 5}CX{sub 2}SO{sub 3}{sup {minus}}, X = H or F) anions have been prepared. Three phases, {beta}{double_prime}-(ET){sub 2}SF{sub 5}CH{sub 2}SO{sub 3}{beta}{prime}-(ET){sub 2}SF{sub 5}CF{sub 2}SO{sub 3} and {beta}{double_prime}-(ET){sub 2}SF{sub 5}CHFSO{sub 3} (A,B, and C respectively) were obtained by electrocrystallization with the corresponding LiSF{sub 5}CX{sub 2}SO{sub 3} electrolytes. The structures of these salts were determined by single-crystal X-ray diffraction, and their physical properties were examined by electrical resistivity measurements as well as by ESR and Raman spectroscopy. The A,C and B salts are considerably different in their crystal structures, physical properties, and electronic structures despite the similarity in the structures of SF{sub 5}CX{sub 2}SO{sub 3}{sup {minus}}(X = H,F) anions. The A salt has two kinds of ET donor molecules with considerably different charge densities. The electronic structure of C has both one-dimensional (1D) and two-dimensional (2D) Fermi surfaces which are similar to those found in the organic superconductor A. The ESR data for the B salt indicate that it opens a spin gap below 45 K. The differences in the physical properties of the three salts were analyzed by calculating the HOMO-HOMO interaction energies between nearest-neighbor ET molecules in their donor molecule layers.

  3. Gamma ray shielding and structural properties of Bi{sub 2}O{sub 3}?PbO?B{sub 2}O{sub 3}?V{sub 2}O{sub 5} glass system

    SciTech Connect (OSTI)

    Kaur, Kulwinder, E-mail: kanwarjitsingh@yahoo.com; Singh, K. J., E-mail: kanwarjitsingh@yahoo.com; Anand, Vikas, E-mail: kanwarjitsingh@yahoo.com [Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India)

    2014-04-24T23:59:59.000Z

    The present work has been undertaken to evaluate the applicability of Bi{sub 2}O{sub 3}?PbO?B{sub 2}O{sub 3}?V{sub 2}O{sub 5} glass system as gamma ray shielding material. Gamma ray mass attenuation coefficient has been determined theoretically using WinXcom computer software developed by National Institute of Standards and Technology. A meaningful comparison of their radiation shielding properties has been made in terms of their half value layer parameter with standard radiation shielding concrete 'barite'. Structural properties of the prepared glass system have been investigated in terms of XRD and FTIR techniques in order to check the possibility of their commercial utility as alternate to conventional concrete for gamma ray shielding applications.

  4. Charge control of antiferromagnetism at PbZr{sub 0.52}Ti{sub 0.48}O{sub 3}/La{sub 0.67}Sr{sub 0.33}MnO{sub 3} interface

    SciTech Connect (OSTI)

    Ma, X.; Zhai, H.; Fang, F.; Lüpke, G., E-mail: gxluep@wm.edu [Department of Applied Science, College of William and Mary, 251 Jamestown Road, Williamsburg, Virginia 23187 (United States); Kumar, A. [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); CSIR-National Physical Laboratory, New Delhi 110012 (India); Dussan, S.; Katiyar, R. S. [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); Zhao, H. B. [Department of Optical Science and Engineering, Fudan University, 220 Handan Road, Shanghai 200433 (China); Scott, J. F. [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); Department of Physics, Cavendish Laboratory, University of Cambridge, Cambridge CB3 OHE (United Kingdom)

    2014-03-31T23:59:59.000Z

    The interfacial spin state of the multiferroic heterostructure PbZr{sub 0.52}Ti{sub 0.48}O{sub 3}/La{sub 0.67}Sr{sub 0.33}MnO{sub 3} and its dependence on ferroelectric polarization is investigated with magnetic second-harmonic generation at 78?K. The spin alignment of Mn ions in the first unit cell layer at the heterointerface can be tuned from ferromagnetic to antiferromagnetic exchange coupled, while the bulk magnetization remains unchanged. Multiple domains of both phases coexist as the ferroelectric polarization is switched. The results will help promote the development of new interface-based functionalities and device concepts.

  5. Transition threshold in Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses

    SciTech Connect (OSTI)

    Wei, Wen-Hou [Department of Applied Physics, Chongqing University, Chongqing 401331 (China); Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Fang, Liang, E-mail: lfang@cqu.edu.cn [Department of Applied Physics, Chongqing University, Chongqing 401331 (China); Shen, Xiang [Laboratory of Infrared Material and Devices, Advanced Technology Research Institute, Ningbo University, Ningbo 315211 (China); Wang, Rong-Ping [Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2014-03-21T23:59:59.000Z

    Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses with Ge content from 7.5 to 32.5?at.?% have been prepared by melt-quench technique, and the physical parameters including glass transition temperature (T{sub g}), density (?), compactness (C), shear elastic moduli (C{sub s}), compression elastic moduli (C{sub c}), refractive index (n), and optical bandgap (E{sub g}) have been investigated. While all these physical parameters show threshold behavior in the glass with a chemically stoichiometric composition. Raman spectra analysis also indicates that, with increasing Ge content, Se-chains or rings gradually disappear until all Se-atoms are consumed in the glass with a chemically stoichiometric composition. With further increasing Ge content, homopolar Ge-Ge and Sb-Sb bonds are formed and the chemical order in the glasses is violated. The threshold behavior of the physical properties in the Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses can be traced to demixing of networks above the chemically stoichiometric composition.

  6. Ternary lithium stannides Li{sub x}T{sub 3}Sn{sub 7-x} (T=Rh, Ir)

    SciTech Connect (OSTI)

    Sreeraj, Puravankara [Institut fuer Anorganische und Analytische Chemie, NRW Graduate School of Chemistry, and Sonderforschungsbereich 458, Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany); Kurowski, Daniel [Institut fuer Anorganische und Analytische Chemie, NRW Graduate School of Chemistry, and Sonderforschungsbereich 458, Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany); Hoffmann, Rolf-Dieter [Institut fuer Anorganische und Analytische Chemie, NRW Graduate School of Chemistry, and Sonderforschungsbereich 458, Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany); Wu Zhiyun [Institut fuer Anorganische und Analytische Chemie, NRW Graduate School of Chemistry, and Sonderforschungsbereich 458, Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany); Poettgen, Rainer [Institut fuer Anorganische und Analytische Chemie, NRW Graduate School of Chemistry, and Sonderforschungsbereich 458, Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany)]. E-mail: pottgen@uni-muenster.de

    2005-11-15T23:59:59.000Z

    The ternary stannides Li{sub x}Rh{sub 3}Sn{sub 7-x} (x=0.45, 0.64, 0.80) and Li{sub x}Ir{sub 3}Sn{sub 7-x} (x=0.62 and 0.66) were synthesized from the elements in sealed tantalum tubes in a water-cooled sample chamber of an induction furnace. The samples were characterized by X-ray diffraction on powders and single crystals. The stannides adopt the cubic Ir{sub 3}Ge{sub 7}-type structure (space group Im3-bar m, Z=4). In this structure type the tin atoms occupy the Wyckoff positions 12d and 16f and form two interpenetrating frameworks consisting of cubes and square antiprisms. The rhodium and iridium atoms center the square antiprisms and are arranged in pairs. With increasing lithium substitution the lattice parameter of Ir{sub 3}Sn{sub 7} (936.7) decreases via 932.2pm (x=0.62) to 931.2pm (x=0.66), while the Ir-Ir distance remains almost the same (290pm). A similar trend is observed for the rhodium compounds. The lithium atoms substitute Sn on both framework sites. However, the 16f site shows a substantially larger preference for Li occupation. This is in contrast to the isotypic magnesium based compounds.

  7. Investigation of site preference of Zn doped Ba{sub 3}Co{sub 2?x}Zn{sub x}Fe{sub 24}O{sub 41} by Mössbauer spectroscopy

    SciTech Connect (OSTI)

    Lim, Jung Tae; Kim, Chul Sung, E-mail: cskim@kookmin.ac.kr [Department of Physics, Kookmin University, Seoul 136-702 (Korea, Republic of)

    2014-05-07T23:59:59.000Z

    The polycrystalline Ba{sub 3}Co{sub 2?x}Zn{sub x}Fe{sub 24}O{sub 41} (x?=?0.0, 0.5, 1.0) samples were prepared by using solid-state-reaction method. The crystal structures and magnetic properties of samples were investigated with x-ray diffractometer, vibrating sample magnetometer, and Mössbauer spectroscopy. The crystal structure of Ba{sub 3}Co{sub 2?x}Zn{sub x}Fe{sub 24}O{sub 41} (x?=?0.0, 0.5, 1.0) samples was determined to be a hexagonal structure with P6{sub 3}/mmc space group at 295 K, and the saturation magnetization (M{sub s}) of Ba{sub 3}Co{sub 2?x}Zn{sub x}Fe{sub 24}O{sub 41} (x?=?0.0, 0.5, 1.0) samples were found to be M{sub s} =?50.9, 53.1, 55.0 emu/g, respectively. From the temperature dependence of magnetization curves under 100 Oe between 4.2 and 740?K, we were able to observe the spin transition, and both spin transition temperature (T{sub s}) and Curie temperature (T{sub C}) decrease with increasing Zn concentration. Mössbauer spectra of all samples were obtained and analyzed at various temperatures ranging from 4.2 to 295 K. With ten-sextets for Fe sites corresponding to the Z-type hexagonal crystallographic sites, all spectra below T{sub C} were fitted by least-square method. In addition, from the site occupation numbers of Fe, calculated from the relative areas fitted to the Mössbauer spectra, we find that Zn ions preferentially occupy the tetrahedral sublattices of down sites.

  8. SWIFT GRB GRB071010B: OUTLIER OF THE E {sup src} {sub peak} - E {sub gamma} AND E {sub iso} - E {sup src} {sub peak} - t {sup src} {sub jet} CORRELATIONS

    SciTech Connect (OSTI)

    Urata, Yuji; Lee, Induk; Ip, Wing Huen [Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan (China); Huang, Kuiyun [Academia Sinica Institute of Astronomy and Astrophysics, Taipei 106, Taiwan (China); Im, Myungshin [Center for the Exploration of the Origin of the Universe, Department of Physics and Astronomy, FPRD, Seoul National University, Shillim-dong, San 56-1, Kwanak-gu, Seoul (Korea, Republic of); Deng Jinsong; Liping Xin; Qiu Yulei; Wei Jianyan; Zheng Weikang [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Krimm, Hans [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ohno, Masanori [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan); Sugita, Satoshi [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tashiro, Makoto [Department of Physics, Saitama University, Shimo-Okubo, Saitama, 338-8570 (Japan); Yamaoka, Kazutaka, E-mail: urata@astro.ncu.edu.t [Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1, Fuchinobe, Sayamihara 229-8558 (Japan)

    2009-11-20T23:59:59.000Z

    We present multi-band results for GRB071010B based on Swift, Suzaku, and ground-based optical observations. This burst is an ideal target to evaluate the robustness of the E{sup src}{sub peak} - E{sub iso} and E{sup src}{sub peak} - E {sub gamma} relations, whose studies have been in stagnation due to the lack of the combined estimation of E{sup src} {sub peak} and long-term optical monitoring. The joint prompt spectral fitting using Swift/Burst Alert Telescope and Suzaku/Wide-band All-sky Monitor data yielded the spectral peak energy as E {sup src} {sub peak} of 86.5{sup +6.4} {sub -6.3} keV and E {sub iso} of 2.25{sup +0.19} {sub -0.16} x 10{sup 52} erg with z = 0.947. The optical afterglow light curve is well fitted by a simple power law with temporal index alpha = -0.60 +- 0.02. The lower limit of temporal break in the optical light curve is 9.8 days. Our multi-wavelength analysis reveals that GRB071010B follows E{sup src}{sub peak} - E{sub iso} but violates the E{sup src}{sub peak} - E{sub gamma} and E{sub iso} - E {sup src}{sub peak} - t {sup src}{sub jet} at more than the 3sigma level.

  9. Effects of K doping on structural and superconducting properties of Bi{sub 1.5}Pb{sub 0.5}Sr{sub 1.8}CaCu{sub 2}O{sub 8+?} compounds

    SciTech Connect (OSTI)

    Belala, K; Mosbah, M. F. [Material Sciences and Applications Research Unit, Physics Department, Constantine 1 University, B.P. 325 Route d'Ain El Bey, 25017 Constantine (Algeria)

    2013-12-16T23:59:59.000Z

    Two kinds of potassium doped Bi(Pb)2212 samples are used to investigate the effect of doping the Bi(Pb)2212 ((Bi,Pb){sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8}) phase by potassium (K): In the first one K is substituted on the Sr site; In the second one K is added. Using the solid state method reaction samples of Bi{sub 1.5}Pb{sub 0.5}(Sr{sub 1.8?x}K{sub x})CaCu{sub 2}O{sub 8+d} and Bi{sub 1.5}Pb{sub 0.5}Sr{sub 1.8}CaCu{sub 2}O{sub 8+d}K{sub x} (0 ? x? 0.05) have been prepared from powders of carbonates and primary oxides having purity over 99%. The samples have been characterized by X ray diffraction (XRD), scanning electron microscopy (SEM) and resistivity versus temperature measurements. Results show how the kind and the rate of doping by potassium affects the structural and transport properties of Bi(Pb)2212 phase.

  10. Fluorine sites in glasses and transparent glass-ceramics of the system Na{sub 2}O/K{sub 2}O/Al{sub 2}O{sub 3}/SiO{sub 2}/BaF{sub 2}

    SciTech Connect (OSTI)

    Bocker, Christian, E-mail: christian.bocker@uni-jena.d [Otto-Schott-Institut, Jena University, Fraunhoferstr. 6, 07743 Jena (Germany); Munoz, Francisco; Duran, Alicia [Instituto de Ceramica y Vidrio (CSIC), Kelsen 5, 28049 Madrid (Spain); Ruessel, Christian [Otto-Schott-Institut, Jena University, Fraunhoferstr. 6, 07743 Jena (Germany)

    2011-02-15T23:59:59.000Z

    The transparent glass-ceramics obtained in the silicate system Na{sub 2}O/K{sub 2}O/SiO{sub 2}/BaF{sub 2} show homogeneously dispersed BaF{sub 2} nano crystals with a narrow size distribution. The X-ray diffraction and the nuclear magnetic resonance spectroscopy were applied to glasses and the respective glass-ceramics in order to clarify the crystallization mechanism and the role of fluorine during crystallization. With an increasing annealing time, the concentration and also the number of crystals remain approximately constant. With an increasing annealing temperature, the crystalline fraction increases until a saturation limit is reached, while the number of crystals decreases and the size of the crystals increases. Fluoride in the glassy network occurs as Al-F-Ba, Al-F-Na and also as Ba-F structures. The latter are transformed into crystalline BaF{sub 2} and fluoride is removed from the Al-F-Ba/Na bonds. However, some fluorine is still present in the glassy phase after the crystallization. -- Graphical abstract: The X-ray diffraction and the nuclear magnetic resonance spectroscopy were applied to glasses in the silicate system Na{sub 2}O/K{sub 2}O/SiO{sub 2}/BaF{sub 2} and the respective glass-ceramics with BaF{sub 2} nano crystals in order to clarify the crystallization mechanism and the role of fluorine during crystallization. Display Omitted Research highlights: {yields} BaF{sub 2} nano crystals are precipitated from a silicate glass system. {yields} Ostwald ripening during the late stage of crystallization does not occur. {yields} Fluorine in the glass is coordinated with Ba as well as Al together with Ba or Na.{yields} In the glass-ceramics, the residual fluorine is coordinated as Al-F-Ba/Na.

  11. Synthesis and structural characterization of Al{sub 7}C{sub 3}N{sub 3}-homeotypic aluminum silicon oxycarbonitride, (Al{sub 7-x}Si{sub x})(O{sub y}C{sub z}N{sub 6-y-z}) (x{approx}1.2, y{approx}1.0 and z{approx}3.5)

    SciTech Connect (OSTI)

    Urushihara, Daisuke; Kaga, Motoaki; Asaka, Toru [Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555 (Japan); Nakano, Hiromi [Cooperative Research Facility Center, Toyohashi University of Technology, Toyohashi 441-8580 (Japan); Fukuda, Koichiro, E-mail: fukuda.koichiro@nitech.ac.jp [Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555 (Japan)

    2011-08-15T23:59:59.000Z

    A new aluminum silicon oxycarbonitride, (Al{sub 5.8}Si{sub 1.2})(O{sub 1.0}C{sub 3.5}N{sub 1.5}), has been synthesized and characterized by X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and electron energy loss spectroscopy (EELS). The title compound is hexagonal with space group P6{sub 3}/mmc and unit-cell dimensions a=0.322508(4) nm, c=3.17193(4) nm and V=0.285717(6) nm{sup 3}. The atom ratios of Al:Si and those of O:C:N were, respectively, determined by EDX and EELS. The initial structural model was successfully derived from the XRPD data by the direct methods and further refined by the Rietveld method. The crystal is most probably composed of four types of domains with nearly the same fraction, each of which is isotypic to Al{sub 7}C{sub 3}N{sub 3} with space group P6{sub 3}mc. The existence of another new oxycarbonitride (Al{sub 6.6}Si{sub 1.4})(O{sub 0.7}C{sub 4.3}N{sub 2.0}), which must be homeotypic to Al{sub 8}C{sub 3}N{sub 4}, has been also demonstrated by XRPD and TEM. - Graphical abstract: A new oxycarbonitride discovered in the Al-Si-O-C-N system, (Al{sub 7-x}Si{sub x})(O{sub y}C{sub z}N{sub 6-y-z}) (x{approx}1.2, y{approx}1.0 and z{approx}3.5). The crystal is composed of four types of domains (I, II, III and IV), and hence the structure is represented by a split-atom model. Individual crystal structures can be regarded as layered structures, which consist of A-type [(Al, Si){sub 4}(O, C, N){sub 4}] unit layers and B-type [(Al, Si)(O, C, N){sub 2}] single layers. Highlights: > (Al{sub 5.8}Si{sub 1.2})(O{sub 1.0}C{sub 3.5}N{sub 1.5}) as a new aluminum silicon oxycarbonitride. > Crystal structure is determined and represented by a split-atom model. > Existence of another new oxycarbonitride (Al{sub 6.6}Si{sub 1.4})(O{sub 0.7}C{sub 4.3}N{sub 2.0}) is demonstrated. > Both new materials are formed by oxidation and nitridation of (Al, Si){sub 6}(O, C){sub 5}.

  12. Transition metal chemistry of main group hydrazides. 16. (Phosphanyl)hydrazines R{sub 2}PN(Me)N(Me)PR{sub 2} as a novel class of chelating bis(phosphines). Synthesis, coordination chemistry, and X-ray structures of cis-[PdCl{sub 2}[(p-BrC{sub 6}H{sub 4}O){sub 2}PN-(Me)N(Me)P(OC{sub 6}H{sub 4}Br-p){sub 2}

    SciTech Connect (OSTI)

    Reedy, V.S.; Katti, K.V. [Center for Radiological Research and MU Research Reactor, Columbia, MO (United States); Barnes, C.L. [Univ. of Missouri, Columbia, MO (United States)

    1995-10-25T23:59:59.000Z

    The alkoxy- and aryloxy-functionalized bis(phosphanyl)hydrazines of the type (OR){sub 2}PN(Me)N(Me)P(OR){sub 2} were obtained from the reactions of the corresponding alcohols and phenols with Cl{sub 2}PN(Me)N(Me)PCl{sub 2} in the presence of Et{sub 3}N. Interaction of these ligands with group 6 metal carbonyl precursors M(CO){sub 4}(NHC{sub 5}H{sub 10}){sub 2}(M=Mo, W) gave the tetracarbonyl complexes of the type cis-[M(CO){sub 4}(OR){sub 2}PN(Me)N(Me)P(OR){sub 2}]. The reactions of the alkoxy and aryloxy-functionalized bis(phosphanyl)hydrazines with Pd(PhCN){sub 2}(Cl){sub 2} or with Pt(COD)Cl{sub 2} resulted in the formation of the complexes of the type cis[MCl{sub 2}(OR){sub 2}PN(Me)N(Me)P(OR){sub 2}]. The ligands are bound cis to the metal center(s) in all the complexes. The structures of all the complexes have been established by combination of spectroscopic and elemental analysis. As representative examples, the authors have determined the structures of cis-[W(CO){sub 4}[(OPh){sub 2}PN(Me)N(Me)P(OPh){sub 2}

  13. Synthesis and photoluminescence properties of the high-brightness Eu{sup 3+}-doped M{sub 2}Gd{sub 4}(MoO{sub 4}){sub 7} (M=Li, Na) red phosphors

    SciTech Connect (OSTI)

    Zhao Chengchun [Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Yin Xin [CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Huang Fuqiang, E-mail: huangfq@mail.sic.ac.cn [CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Hang Yin, E-mail: yhang@siom.ac.cn [Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2011-12-15T23:59:59.000Z

    A series of red-emitting phosphors Eu{sup 3+}-doped M{sub 2}Gd{sub 4}(MoO{sub 4}){sub 7} (M=Li, Na) have been successfully synthesized at 850 Degree-Sign C by solid state reaction. The excitation spectra of the two phosphors reveal two strong excitation bands at 396 nm and 466 nm, respectively, which match well with the two popular emissions from near-UV and blue light-emitting diode chips. The intensity of the emission from {sup 5}D{sub 0} to {sup 7}F{sub 2} of M{sub 2}(Gd{sub 1-x}Eu{sub x}){sub 4}(MoO{sub 4}){sub 7} phosphors with the optimal compositions of x=0.85 for Li or x=0.70 for Na is about five times higher than that of Y{sub 2}O{sub 3}:Eu{sup 3+}. The quantum efficiencies of the entitled phosphors excited under 396 nm and 466 nm are also investigated and compared with commercial phosphors Sr{sub 2}Si{sub 5}N{sub 8}:Eu{sup 2+} and Y{sub 3}A{sub 5}O{sub 12}:Ce{sup 3+}. The experimental results indicate that the Eu{sup 3+}-doped M{sub 2}Gd{sub 4}(MoO{sub 4}){sub 7} (M=Li, Na) phosphors are promising red-emitting phosphors pumped by near-UV and blue light. - Graphical Abstract: The intensity of the red emission of M{sub 2}(Gd{sub 1-x}Eu{sub x}){sub 4}(MoO{sub 4}){sub 7} (M=Li, Na) phosphors with the optimal compositions is about five times higher than that of Y{sub 2}O{sub 3}:Eu{sup 3+}. Highlights: Black-Right-Pointing-Pointer Two novel Eu{sup 3+}-doped red phosphors (Na{sub 2}Gd{sub 4}(MoO{sub 4}){sub 2}, Li{sub 2}Gd{sub 4}(MoO{sub 4}){sub 7}) were synthesized. Black-Right-Pointing-Pointer Their emission intensities are about five times higher than that of Y{sub 2}O{sub 3}:Eu{sup 3+}. Black-Right-Pointing-Pointer Their quantum efficiencies are higher than that of commercial red phosphor Sr{sub 2}Si{sub 5}N{sub 8}:Eu{sup 2+}.

  14. Electrochromic investigation of sol-gel-derived thin films of TiO{sub 2}-V{sub 2}O{sub 5}

    SciTech Connect (OSTI)

    Ivanova, T. [Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, Blvd. 'Tzarigaradsko chaussee' 72, 1784 Sofia (Bulgaria)]. E-mail: tativan@phys.bas.bg; Harizanova, A. [Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, Blvd. 'Tzarigaradsko chaussee' 72, 1784 Sofia (Bulgaria)

    2005-03-08T23:59:59.000Z

    Thin films of TiO{sub 2} and TiO{sub 2}-V{sub 2}O{sub 5} were obtained by dip-coating sol-gel technique. Sols were prepared from titanium ethoxide and inorganic V{sub 2}O{sub 5} sol received by dissolution of vanadium pentoxide in hydrogen peroxide. Sol-gel TiO{sub 2} and TiO{sub 2}-V{sub 2}O{sub 5} films are deposited on conductive glass substrates. TiO{sub 2} and TiO{sub 2}-V{sub 2}O{sub 5} systems were characterized by FTIR and Raman spectroscopy. Optical transmittance measurements were carried out. Electrochromic characterization was recorded by cyclic voltammetry using three-electrode arrangement. All samples demonstrated electrochromic effect.

  15. Processing of the intermetallic matrix composite Ni[sub 76]Al[sub 23. 9]B[sub 0. 1]/[alpha]-Al[sub 2]O[sub 3] from nickel-plated alumina powder

    SciTech Connect (OSTI)

    Chiou, W.C.; Hu, C.T. (National Tsing Hua Univ., Hsinchu (Taiwan, Province of China). Dept. of Materials Science and Engineering)

    1994-09-01T23:59:59.000Z

    The nickel aluminide intermetallic compound Ni[sub 3]Al exhibits many extraordinary properties. In addition, the intrinsic brittleness of the polycrystalline Ni[sub 76]Al[sub 24] compound at ambient temperatures is eliminated by microalloying with boron (B 0.1 percent). In the present report the authors demonstrate a new approach to prepare Ni[sub 76]Al[sub 23.9]B[sub 0.1]/[alpha]-Al[sub 2]O[sub 3] IMC from electroless nickel-boron-plated [alpha]-Al[sub 2]O[sub 3] powder mixed with Ni and Al powder and sintered. Expensive facilities, i.e. HIP and vacuum HP etc., are unnecessary, but ductile fracture behavior and excellent elongation are observed.

  16. Luminescence and superradiance in electron-beam-excited Al{sub x}Ga{sub 1?x}N

    SciTech Connect (OSTI)

    Bokhan, P. A.; Gugin, P. P.; Zakrevsky, Dm. E.; Malin, T. V. [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, 13, Lavrentieva av., Novosibirsk 630090 (Russian Federation); Zhuravlev, K. S.; Osinnykh, I. V. [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, 13, Lavrentieva av., Novosibirsk 630090 (Russian Federation); Novosibirsk State University, 2 Pirogova Str., Novosibirsk 630090 (Russian Federation); Solomonov, V. I.; Spirina, A. V. [Institute of Electrophysics, Ural Division of the Russian Academy of Sciences, 106, Amundsen str., Ekaterinburg 620016 (Russian Federation)

    2014-09-21T23:59:59.000Z

    Luminescence and superradiance characteristics of 0.5–1.2-?m thick Al{sub x}Ga{sub 1?x}N films grown by molecular-beam epitaxy on sapphire substrates were studied under excitation of the films with low-energy (<20?keV) and high-energy (170?keV) electron beams. In both cases, the luminescence spectra looked quite similarly; they exhibited a band-edge luminescence with x-dependent wavelength ranging from 365?nm to 310?nm and a broadband emission taking over the whole visible spectral region. Superradiance within the broad band was obtained by pumping the samples with powerful an electron beam in the form of an open-discharge-generated filament.

  17. XAFS near-edge structure of As[sub 2]S[sub 3]: A comparison of experiment and theory

    SciTech Connect (OSTI)

    Pfeiffer, G. (Max-Planck-Institut fuer Festkoerperforschung, Postfach 800665, 70506 Stuttgart (Germany)); Rehr, J.J. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States)); Sayers, D.E. (Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (United States))

    1995-01-01T23:59:59.000Z

    The experimental As [ital K]-edge x-ray-absorption fine structure of As[sub 2]S[sub 3] is analyzed in detail and compared to data calculated theoretically from a model structure. The experimental spectrum is resolved into two components, one representing a bound excited state resonance and a second due to transitions to the continuum. The bound state resonance is located 6.1 eV below the continuum threshold and is fitted by a Lorentzian. The continuum structure is constructed using theoretically calculated [chi] and absorption cross section data together with an arctangent function simulating the absorption and lifetime at the continuum edge. For the theoretical calculation, the [ital ab] [ital initio] code FEFF was applied to an atomic cluster representing the amorphous solid. The results show that multiple scattering effects give rise only to small contributions in the region of the continuum threshold. They are negligible for higher energies.

  18. Ordered nanoporous carbon for increasing CO{sub 2} capture

    SciTech Connect (OSTI)

    Yoo, Hye-Min; Lee, Seul-Yi [Korea CCS R and D Center, Korea Institute of Energy Research, 152 Gajeongro, Yuseoung-gu, Daejeon 305-343 (Korea, Republic of); Department of Chemistry, Inha University, 100 Inharo, Nam-gu, Incheon 402-751 (Korea, Republic of); Park, Soo-Jin, E-mail: sjpark@inha.ac.kr [Korea CCS R and D Center, Korea Institute of Energy Research, 152 Gajeongro, Yuseoung-gu, Daejeon 305-343 (Korea, Republic of); Department of Chemistry, Inha University, 100 Inharo, Nam-gu, Incheon 402-751 (Korea, Republic of)

    2013-01-15T23:59:59.000Z

    Ordered nanoporous carbons (ONCs) were prepared using a soft-templating method. The prepared ONCs materials were subjected to a controlled carbonization temperature over the temperature range, 700-1000 Degree-Sign C, to increase the specific surface area and total pore volume of ordered nanoporous carbon followed by carbonization of the phenolic resin. ONCs materials synthesized at various carbonization temperatures were used as adsorbents to improve the CO{sub 2} adsorption efficiency. The surface properties of the ONCs materials were examined by X-ray photoelectron spectroscopy. The structural properties of the ONCs materials were analyzed by X-ray diffraction. The textural properties of the ONCs materials were examined using the N{sub 2}/77 K adsorption isotherms according to the Brunauer-Emmett-Teller equation. The CO{sub 2} adsorption capacity was measured by CO{sub 2} isothermal adsorption at 298 K/30 bar and 298 K/1 bar. The carbonization temperature was found to have a major effect on the CO{sub 2} adsorption capacity, resulting from the specific surface area and total pore volumes of the ONCs materials. - Graphical abstract: This schematic diagram described synthesis of ONCs. Highlights: Black-Right-Pointing-Pointer ONCs materials can be prepared readily using the direct-triblock-copolymer-templating method. Black-Right-Pointing-Pointer The distributions show that prominent development can be observed around the micro-pore region. Black-Right-Pointing-Pointer The soft-templating method provides opportunities for controlling the pore structure of ONCs. Black-Right-Pointing-Pointer From thermal power plants for CO2 capture by adsorption technology, is a new direction.

  19. Two-dimensional titanium carbonitrides and their hydroxylated derivatives: Structural, electronic properties and stability of MXenes Ti{sub 3}C{sub 2?x}N{sub x}(OH){sub 2} from DFTB calculations

    SciTech Connect (OSTI)

    Enyashin, A.N.; Ivanovskii, A.L., E-mail: ivanovskii@ihim.uran.ru

    2013-11-15T23:59:59.000Z

    The structural, electronic properties and stability of the new MXene compounds—two-dimensional pristine carbonitrides Ti{sub 3}C{sub 2?x}N{sub x} and their hydroxylated derivatives Ti{sub 3}C{sub 2?x}N{sub x}(OH){sub 2} are studied by means of DFTB calculations. The genesis of the properties is discussed in the sequence: binary MXenes Ti{sub 3}C{sub 2} (Ti{sub 3}N{sub 2})?hydroxylated forms Ti{sub 3}C{sub 2}(OH){sub 2} (Ti{sub 3}N{sub 2}(OH){sub 2})?pristine MXene Ti{sub 3}C{sub 2?x}N{sub x}?hydroxylated Ti{sub 3}C{sub 2?x}N{sub x}(OH){sub 2}. All examined materials are metallic-like. The most favorable type of OH-covering is presented by the occupation of the hollow sites between three neighboring carbon (nitrogen) atoms. Two-dimensional MXene carbonitrides with random distribution of C and N atoms are found to be thermodynamically more favorable. - Graphical abstract: The side views of the optimized atomic structures of some examined hydroxylated derivatives of MXene Ti{sub 3}CN and their electronic band structures. Display Omitted - Highlights: • Very recently 2D titanium carbonitrides have been synthesized. • Structural, electronic properties and stability for these materials were evaluated. • The hydroxylated derivatives of 2D titanium carbonitrides are examined.

  20. Oil and Natural Gas in Sub-Saharan Africa

    U.S. Energy Information Administration (EIA) Indexed Site

    Natural Gas in Sub-Saharan Africa August 1, 2013 2 Sub-Saharan Africa Source: U.S. Department of State Liquid Fuels Reserves and Production in Sub-Saharan Africa 3 4 Sub-Saharan...

  1. Structural distortion in RPt sub 2 Sn sub 2 compounds (R = rare earth)

    SciTech Connect (OSTI)

    Latroche, M.; Selsane, M.; Godart, C.; Schiffmacher, G. (Centre National de la Recherche Scientifique (CNRS), 92 - Meudon-Bellevue (France)); Beyerman, W.P.; Thompson, J.D. (Los Alamos National Lab., NM (USA))

    1991-01-01T23:59:59.000Z

    CeM{sub 2}X{sub 2} compounds (M-transition metals, X = Si, Ge, Sn) exhibit very exotic properties such as intermediate valence state, heavy fermion, magnetism, and superconductivity. Most of them crystallize in the ThCr{sub 2}Si{sub 2} type structure (14/nmm) while a few adopt the CeBe{sub 2}Ge{sub 2} primitive one (P4/nmmm). Among these compounds, CePt{sub 2}Sn{sub 2} has the heaviest known specific heat coefficient ({gamma} = 3.5 J/mol-K{sup 2}) and orders antiferromagnetically at T{sub N} = 0.88 K. Samples of CePt{sub 2}Sn{sub 2}, Ce{sub 0.e}La{sub 0.2}Pt{sub 2}Sn{sub 2}, and LaPt{sub 2}Sn{sub 2} have been studied by X-ray powder diffraction experiments including Rietveld calculations before and after annealing. As-cast samples can be indexed in the tetragonal primitive cell; however, re- examination of annealed samples (1 3 days at 800{degrees}C and 3 weeks at 700{degrees}C) reveals a monoclinic distortion of the lattice. Such a distortion has already been observed for CeNi{sub 2}Sn{sub 2}. Furthermore, our diffraction patterns show evidence for superlattice lines at twice the unit cell parameters, which was verified by transmission electron microscopy. Microprobes analysis on these samples show that the Pt sublattice is slightly substoichiometric (97.5%). Thus strains due to large atomic radii and ordering of Pt vacancies could be responsible for the monoclinic distortion and superlattice lines. 13 refs., 3 figs., 1 tab.

  2. Microstructure and hydriding studies of AB/sub 5/ hydrogen storage compounds. Final report

    SciTech Connect (OSTI)

    Goodell, P.D.; Sandrock, G.D.; Huston, E.L.

    1980-01-01T23:59:59.000Z

    New data on the microstructure, pressure-composition-temperature, and absorption/desorption kinetics of AB/sub 5/ metal hydrides are presented. The most significant result to emerge from the investigation is that many of the AB/sub 5/ metal hydrides, especially the LaNi/sub 5/ related materials, show instantaneous absorption and desorption response in proportion to the amount of cooling or heating which is provided. Eight categories of materials were studied: reference alloys (LaNi/sub 5/, LaNi/sub 4/ /sub 9/Al/sub 0/ /sub 1/, LaNi/sub 3/Co/sub 2/); Ni second phase particles (LaNi/sub 5/ /sub 67/, LaNi/sub 7/, LaNi/sub 11/ /sub 3/); eutectoid microstructure (SmCo/sub 5/); other second phases (LaNi/sub 3/ /sub 8/Fe/sub 1/ /sub 2/, LaNi/sub 3/ /sub 5/Cr/sub 1/ /sub 5/, LaNi/sub 4/Cr, LaNi/sub 4/Si; LaNi/sub 4/Sn, MNi/sub 4/Sn, MNi/sub 4/ /sub 3/Al/sub 0/ /sub 7/); substitutional elements (LaNi/sub 4/Cu, LaNi/sub 4/ /sub 5/Pd/sub 0/ /sub 5/, LaNi/sub 4/ /sub 7/Sn/sub 0/ /sub 3/, LaNi/sub 4/ /sub 8/C/sub 0/ /sub 2/, MNi/sub 4/ /sub 3/Mn/sub 0/ /sub 7/); surface active elements (LaNi/sub 4/ /sub 8/B/sub 0/ /sub 2/, LaNi/sub 4/ /sub 9/S/sub 0/ /sub 1/, LaNi/sub 4/ /sub 9/Se/sub 0/ /sub 1/); large diameter atom substitutions (Mg/sub 0/ /sub 1/La/sub 0/ /sub 9/Ni/sub 5/, Ca/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/, Sr/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/, Ba/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/); other compositions (LaNi/sub 3/); and Pd plating (electroless plated samples and mechanically alloyed specimens).

  3. Synthesis, crystal and electronic structure, and physical properties of the new lanthanum copper telluride La{sub 3}Cu{sub 5}Te{sub 7}

    SciTech Connect (OSTI)

    Zelinska, Mariya; Assoud, Abdeljalil [Department of Chemistry, University of Waterloo, Waterloo, ON, Canada N2L 3G1 (Canada); Kleinke, Holger, E-mail: kleinke@uwaterloo.c [Department of Chemistry, University of Waterloo, Waterloo, ON, Canada N2L 3G1 (Canada)

    2011-03-15T23:59:59.000Z

    The new lanthanum copper telluride La{sub 3}Cu{sub 5-x}Te{sub 7} has been obtained by annealing the elements at 1073 K. Single-crystal X-ray diffraction studies revealed that the title compound crystallizes in a new structure type, space group Pnma (no. 62) with lattice dimensions of a=8.2326(3) A, b=25.9466(9) A, c=7.3402(3) A, V=1567.9(1) A{sup 3}, Z=4 for La{sub 3}Cu{sub 4.86(4)}Te{sub 7}. The stru