National Library of Energy BETA

Sample records for namibia sb st

  1. Bicon Namibia Consulting Engineers | Open Energy Information

    Open Energy Info (EERE)

    Name: Bicon Namibia Consulting Engineers Place: Windhoek, Namibia Sector: Wind energy Product: Windhoek-based engineering consultancy firm. Provides design and supervision of...

  2. Namibia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Unexpected > operator. SWERA logo.png SWERA View the Solar and Wind Energy Resource Atlas for Namibia. 5 Programs Namibia-UNEP Green Economy Advisory Services National Action...

  3. Namibia | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Namibia NNSA Supports IAEA Regional Training in Zambia on Management Practices for Uranium The International Atomic Energy Agency (IAEA), European Commission and National Nuclear Security Administration (NNSA) co-sponsored a training course in Livingstone, Zambia this week focusing on good management practices for uranium ore concentrate (UOC). The Zambia Radiation Protection Authority

  4. ST

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

    ST Meeting of the Joint Working Group on Safety for the U.S.-PRC Coordinating Committee of Fusion Energy (U.S.-PRC Safety Monitoring Program) Meeting in China, December 9-14, 2009 Respectfully submitted on April 12, 2010 to: Barry Sullivan U.S. DOE - Office of Fusion Energy Sciences Professor Yican Wu, Deputy Director Academy of Science Institute for Plasma Physics Professor Yong Liu, Director Southwestern Institute of Physics - Center for Fusion Science Prepared by: Lee Cadwallader, Rick

  5. MHK Projects/GPP Namibia | Open Energy Information

    Open Energy Info (EERE)

    Namibia utility, GPP (subsidiary of Southern African Utility SELCo), for a 1.5 MW unit. Once this unit reaches its agreed performance criteria, it will be followed by a further 10...

  6. SB 1149 Schools Program

    Office of Energy Efficiency and Renewable Energy (EERE)

    Oregon's retail electricity restructuring law, SB 1149, includes a requirement for the state's two largest utilities, Pacific Power and Portland General Electric, to collect a 3% public purpose...

  7. CRAD, NNSA- Safety Basis (SB)

    Broader source: Energy.gov [DOE]

    CRAD for Safety Basis (SB). Criteria Review and Approach Documents (CRADs) that can be used to conduct a well-organized and thorough assessment of elements of safety and health programs.

  8. via Spence St 39 min

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

    via Spence St 39 min

  9. DWPF SB6 INITIAL CPC FLOWSHEET TESTING SB6-1 TO SB6-4L TESTS OF SB6-A AND SB6-B SIMULANTS

    SciTech Connect (OSTI)

    Lambert, D.; Pickenheim, B.; Best, D.

    2009-09-09

    The Defense Waste Processing Facility (DWPF) will transition from Sludge Batch 5 (SB5) processing to Sludge Batch 6 (SB6) processing in late fiscal year 2010. Tests were conducted using non-radioactive simulants of the expected SB6 composition to determine the impact of varying the acid stoichiometry during the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) processes. The work was conducted to meet the Technical Task Request (TTR) HLW/DWPF/TTR-2008-0043, Rev.0 and followed the guidelines of a Task Technical and Quality Assurance Plan (TT&QAP). The flowsheet studies are performed to evaluate the potential chemical processing issues, hydrogen generation rates, and process slurry rheological properties as a function of acid stoichiometry. These studies were conducted with the estimated SB6 composition at the time of the study. This composition assumed a blend of 101,085 kg of Tank 4 insoluble solids and 179,000 kg of Tank 12 insoluble solids. The current plans are to subject Tank 12 sludge to aluminum dissolution. Liquid Waste Operations assumed that 75% of the aluminum would be dissolved during this process. After dissolution and blending of Tank 4 sludge slurry, plans included washing the contents of Tank 51 to {approx}1M Na. After the completion of washing, the plan assumes that 40 inches on Tank 40 slurry would remain for blending with the qualified SB6 material. There are several parameters that are noteworthy concerning SB6 sludge: (1) This is the second batch DWPF will be processing that contains sludge that has had a significant fraction of aluminum removed through aluminum dissolution; (2) The sludge is high in mercury, but the projected concentration is lower than SB5; (3) The sludge is high in noble metals, but the projected concentrations are lower than SB5; and(4) The sludge is high in U and Pu - components that are not added in sludge simulants. Six DWPF process simulations were completed in 4-L laboratory-scale equipment using

  10. Scavenging Elemental Sb Through Addition of NbSb to Mm0.9Fe3...

    Office of Scientific and Technical Information (OSTI)

    Title: Scavenging Elemental Sb Through Addition of NbSb to Mm0.9Fe3.5Co0.5S12 Skutterudites Authors: Zhang, Long ; Zhou, Chen ; Morelli, Donald T ; Sakamoto, Jeffrey Publication ...

  11. AlGaAsSb/GaSb Distributed Bragg Reflectors Grown by Organometallic Vapor Phase Epitaxy

    SciTech Connect (OSTI)

    C.A. Wang; C.J. Vineis; D.R. Calawa

    2002-02-13

    The first AlGaAsSb/GaSb quarter-wave distributed Bragg reflectors grown by metallic vapor phase epitaxy are reported. The peak reflectance is 96% for a 10-period structure.

  12. Method of making an InAsSb/InAsSbP diode lasers

    DOE Patents [OSTI]

    Razeghi, Manijeh

    1997-01-01

    InAsSb/InAsSbP/InAs Double Heterostructures (DH) and Separate Confinement Heterostructure Multiple Quantum Well (SCH-MQW) structures are taught wherein the ability to tune to a specific wavelength within 3 .mu.m to 5 .mu.m is possible by varying the ratio of As:Sb in the active layer.

  13. Method of making an InAsSb/InAsSbP diode lasers

    DOE Patents [OSTI]

    Razeghi, M.

    1997-08-19

    InAsSb/InAsSbP/InAs Double Heterostructures (DH) and Separate Confinement Heterostructure Multiple Quantum Well (SCH-MQW) structures are taught wherein the ability to tune to a specific wavelength within 3 {micro}m to 5 {micro}m is possible by varying the ratio of As:Sb in the active layer. 9 figs.

  14. Relation between the magnetization and the electrical properties of alloy GaSb-MnSb films

    SciTech Connect (OSTI)

    Koplak, O. V.; Polyakov, A. A.; Davydov, A. B.; Morgunov, R. B.; Talantsev, A. D.; Kochura, A. V.; Fedorchenko, I. V.; Novodvorskii, O. A.; Parshina, L. S.; Khramova, O. D.; Shorokhova, A. V.; Aronzon, B. A.

    2015-06-15

    The influence of the charge carrier concentration on the magnetic properties of GaSb-MnSb alloys is studied. The ferromagnetism of GaSb-MnSb films is caused by the presence of MnSb granules and manifests itself in both magnetometric measurements and the presence of an anisotropic magnetoresistance and the anomalous Hall effect. Electric conduction is executed by charge carriers (holes) in a GaSb matrix. The magnetization of clusters depends on stoichiometry and the concentration of Mn{sup 2+} and Mn{sup 3+} ions, which is specified by the film growth conditions. At high film growth temperatures, ferromagnetic clusters containing Mn{sup 2+} ions mainly form. At low growth temperatures, an antiferromagnetic phase containing Mn{sup 3+} ions forms.

  15. SbSI nanocrystal formation in AsSbSI glass under laser beam

    SciTech Connect (OSTI)

    Azhniuk, Yu.M.; Stoyka, V.; Petryshynets, I.; Rubish, V.M.; Guranich, O.G.; Gomonnai, A.V.; Zahn, D.R.T.

    2012-06-15

    Highlights: ? AsSbSI glasses are obtained by co-melting of As{sub 2}S{sub 3} and SbSI. ? The glass structure and composition are confirmed by SEM, EDX, and Raman studies. ? Laser-induced crystallization of SbSI from the glass is observed by Raman spectroscopy. -- Abstract: AsSbSI glasses are obtained by co-melting of As{sub 2}S{sub 3} and SbSI in a broad compositional interval. Their structure and composition are confirmed by the studies of scanning electron microscopy, energy dispersive X-ray spectroscopy, and micro-Raman scattering. Laser-induced crystallization of SbSI crystallites from the glass matrix is observed in the course of the micro-Raman measurement as a result of local laser beam heating.

  16. Growth mechanisms of GaSb heteroepitaxial films on Si with an AlSb buffer layer

    SciTech Connect (OSTI)

    Vajargah, S. Hosseini; Botton, G. A.; Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4M1; Canadian Centre for Electron Microscopy, McMaster University, Hamilton, Ontario L8S 4M1 ; Ghanad-Tavakoli, S.; Preston, J. S.; Kleiman, R. N.; Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4L7; Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4L7

    2013-09-21

    The initial growth stages of GaSb epilayers on Si substrates and the role of the AlSb buffer layer were studied by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Heteroepitaxy of GaSb and AlSb on Si both occur by Volmer-Weber (i.e., island mode) growth. However, the AlSb and GaSb islands have distinctly different characteristics as revealed through an atomic-resolution structural study using Z-contrast of HAADF-STEM imaging. While GaSb islands are sparse and three dimensional, AlSb islands are numerous and flattened. The introduction of 3D island-forming AlSb buffer layer facilitates the nucleation of GaSb islands. The AlSb islands-assisted nucleation of GaSb islands results in the formation of drastically higher quality planar film at a significantly smaller thickness of films. The interface of the AlSb and GaSb epilayers with the Si substrate was further investigated with energy dispersive X-ray spectrometry to elucidate the key role of the AlSb buffer layer in the growth of GaSb epilayers on Si substrates.

  17. ST. LCUIS ST. LallS JOKIN KFms Clrv S!. LrMS ST. Lcm

    Office of Legacy Management (LM)

    Ho. 30 !2121/87 smt6w cm ST. LCUIS ST. LallS JOKIN KFms Clrv S!. LrMS ST. Lcm

  18. Lattice-matched epitaxial GaInAsSb/GaSb thermophotovoltaic devices

    SciTech Connect (OSTI)

    Wang, C.A.; Choi, H.K.; Turner, G.W.; Spears, D.L.; Manfra, M.J.; Charache, G.W.

    1997-05-01

    The materials development of Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} alloys for lattice-matched thermophotovoltaic (TPV) devices is reported. Epilayers with cutoff wavelength 2--2.4 {micro}m at room temperature and lattice-matched to GaSb substrates were grown by both low-pressure organometallic vapor phase epitaxy and molecular beam epitaxy. These layers exhibit high optical and structural quality. For demonstrating lattice-matched thermophotovoltaic devices, p- and n-type doping studies were performed. Several TPV device structures were investigated, with variations in the base/emitter thicknesses and the incorporation of a high bandgap GaSb or AlGaAsSb window layer. Significant improvement in the external quantum efficiency is observed for devices with an AlGaAsSb window layer compared to those without one.

  19. DWPF simulant CPC studies for SB8

    SciTech Connect (OSTI)

    Koopman, D. C.; Zamecnik, J. R.

    2013-06-25

    The Savannah River National Laboratory (SRNL) accepted a technical task request (TTR) from Waste Solidification Engineering to perform simulant tests to support the qualification of Sludge Batch 8 (SB8) and to develop the flowsheet for SB8 in the Defense Waste Processing Facility (DWPF). These efforts pertained to the DWPF Chemical Process Cell (CPC). Separate studies were conducted for frit development and glass properties (including REDOX). The SRNL CPC effort had two primary phases divided by the decision to drop Tank 12 from the SB8 constituents. This report focuses on the second phase with SB8 compositions that do not contain the Tank 12 piece. A separate report will document the initial phase of SB8 testing that included Tank 12. The second phase of SB8 studies consisted of two sets of CPC studies. The first study involved CPC testing of an SB8 simulant for Tank 51 to support the CPC demonstration of the washed Tank 51 qualification sample in the SRNL Shielded Cells facility. SB8-Tank 51 was a high iron-low aluminum waste with fairly high mercury and moderate noble metal concentrations. Tank 51 was ultimately washed to about 1.5 M sodium which is the highest wash endpoint since SB3-Tank 51. This study included three simulations of the DWPF Sludge Receipt and Adjustment Tank (SRAT) cycle and Slurry Mix Evaporator (SME) cycle with the sludge-only flowsheet at nominal DWPF processing conditions and three different acid stoichiometries. These runs produced a set of recommendations that were used to guide the successful SRNL qualification SRAT/SME demonstration with actual Tank 51 washed waste. The second study involved five SRAT/SME runs with SB8-Tank 40 simulant. Four of the runs were designed to define the acid requirements for sludge-only processing in DWPF with respect to nitrite destruction and hydrogen generation. The fifth run was an intermediate acid stoichiometry demonstration of the coupled flowsheet for SB8. These runs produced a set of processing

  20. St. Bernard Project Update

    Broader source: Energy.gov [DOE]

    The folks at St. Bernard Project are helping survivors of Hurricane Katrina get back into their homes -- and are using new technologies to reduce energy and save money for the returning residents.

  1. Peter St. John | Bioenergy | NREL

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

    St. John Peter St. John Postdoctoral Researcher, Systems Biology and Metabolic Engineering Peter.StJohn@nrel.gov | 303-275-4399 Education Peter St. John received his B.S. in chemical engineering from Tufts University in 2010, followed by his Ph.D. in chemical engineering from the University of California at Santa Barbara in 2015. During his Ph.D., St. John applied techniques from systems biology and dynamic systems to understand the gene regulatory networks underlying mammalian circadian

  2. DWPF Simulant CPC Studies For SB8

    SciTech Connect (OSTI)

    Newell, J. D.

    2013-09-25

    Prior to processing a Sludge Batch (SB) in the Defense Waste Processing Facility (DWPF), flowsheet studies using simulants are performed. Typically, the flowsheet studies are conducted based on projected composition(s). The results from the flowsheet testing are used to 1) guide decisions during sludge batch preparation, 2) serve as a preliminary evaluation of potential processing issues, and 3) provide a basis to support the Shielded Cells qualification runs performed at the Savannah River National Laboratory (SRNL). SB8 was initially projected to be a combination of the Tank 40 heel (Sludge Batch 7b), Tank 13, Tank 12, and the Tank 51 heel. In order to accelerate preparation of SB8, the decision was made to delay the oxalate-rich material from Tank 12 to a future sludge batch. SB8 simulant studies without Tank 12 were reported in a separate report.1 The data presented in this report will be useful when processing future sludge batches containing Tank 12. The wash endpoint target for SB8 was set at a significantly higher sodium concentration to allow acceptable glass compositions at the targeted waste loading. Four non-coupled tests were conducted using simulant representing Tank 40 at 110-146% of the Koopman Minimum Acid requirement. Hydrogen was generated during high acid stoichiometry (146% acid) SRAT testing up to 31% of the DWPF hydrogen limit. SME hydrogen generation reached 48% of of the DWPF limit for the high acid run. Two non-coupled tests were conducted using simulant representing Tank 51 at 110-146% of the Koopman Minimum Acid requirement. Hydrogen was generated during high acid stoichiometry SRAT testing up to 16% of the DWPF limit. SME hydrogen generation reached 49% of the DWPF limit for hydrogen in the SME for the high acid run. Simulant processing was successful using previously established antifoam addition strategy. Foaming during formic acid addition was not observed in any of the runs. Nitrite was destroyed in all runs and no N2O was detected

  3. Fragile structural transition in Mo3Sb7

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yan, Jiaqiang -Q.; McGuire, Michael A; May, Andrew F; Parker, David S.; Mandrus, D. G.; Sales, Brian C.

    2015-01-01

    Mo3Sb7 single crystals lightly doped with Cr, Ru, or Te are studied in order to explore the interplay between superconductivity, magnetism, and the cubic-tetragonal structural transition. The structural transition at 53 K is extremely sensitive to Ru or Te substitution which introduces additional electrons, but robust against Cr substitution. We observed no sign of a structural transition in superconducting Mo2.91Ru0.09Sb7 and Mo3Sb6.975Te0.025. In contrast, 3 at.% Cr doping only slightly suppresses the structural transition to 48 K while leaving no trace of superconductivity above 1.8 K. Analysis of magnetic properties suggests that the interdimer interaction in Mo3Sb7 is near amore » critical value and essential for the structural transition. Futhermore, all dopants suppress the superconductivity of Mo3Sb7. The tetragonal structure is not necessary for superconductivity.« less

  4. The reaction mechanism of SnSb and Sb thin film anodes for Na-ion batteries studied by X-ray diffraction, 119Sn and 121Sb Mössbauer spectroscopies

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baggetto, Loïc; Hah, Hien-Yoong; Jumas, Jean-Claude; Johnson, Charles E.; Johnson, Jacqueline A.; Keum, Jong K.; Bridges, Craig A.; Veith, Gabriel M.

    2014-06-01

    The electrochemical reaction of Sb and SnSb anode materials with Na results in the formation of amorphous materials. To understand the resulting phases and electrochemical capacities we studied the reaction products local order using 119Sn and 121Sb Mössbauer spectroscopies in conjunction with measurements performed on model powder compounds of Na-Sn and Na-Sb to further clarify the reactions steps. For pure Sb the discharge (sodiation) starts with the formation of an amorphous phase composed of atomic environments similar to those found in NaSb, and proceeds further by the formation of environments similar to that present in Na3Sb. The reversible reaction takesmore » place during a large portion of the charge process. At full charge the anode material still contains a substantial fraction of Na, which explains the lack of recrystallization into crystalline Sb. The reaction of SnSb yields Na3Sb crystalline phase at full discharge at higher temperatures (65 and 95°C) while the room temperature reaction yields amorphous compounds. The electrochemically-driven, solid-state amorphization reaction occurring at room temperature is governed by the simultaneous formation of Na-coordinated Sn and Sb environments, as monitored by the decrease (increase) of the 119Sn (121Sb) Mössbauer isomer shifts. Overall, the monitoring of the hyperfine parameters enables to correlate the changes in Na content to the individual Sn and Sb local chemical environments.« less

  5. The reaction mechanism of SnSb and Sb thin film anodes for Na-ion batteries studied by X-ray diffraction, 119Sn and 121Sb M ssbauer spectroscopies

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baggetto, Loic; Hah, Hien-Yoong; Jumas, Dr. Jean-Claude; Johnson, Prof. Dr. Charles E.; Johnson, Jackie A.; Keum, Jong Kahk; Bridges, Craig A; Veith, Gabriel M

    2014-01-01

    The electrochemical reaction of Sb and SnSb anode materials with Na results in the formation of amorphous materials. To understand the resulting phases and electrochemical capacities we studied the reaction products local order using 119Sn and 121Sb M ssbauer spectroscopies in conjunction with measurements performed on model powder compounds of Na-Sn and Na-Sb to further clarify the reactions steps. For pure Sb the discharge (sodiation) starts with the formation of an amorphous phase composed of atomic environments similar to those found in NaSb, and proceeds further by the formation of environments similar to that present in Na3Sb. The reversible reactionmore » takes place during a large portion of the charge process. At full charge the anode material still contains a substantial fraction of Na, which explains the lack of recrystallization into crystalline Sb. The reaction of SnSb yields Na3Sb crystalline phase at full discharge at higher temperatures (65 and 95 C) while the room temperature reaction yields amorphous compounds. The electrochemically-driven, solid-state amorphization reaction occurring at room temperature is governed by the simultaneous formation of Na-coordinated Sn and Sb environments, as monitored by the decrease (increase) of the 119Sn (121Sb) M ssbauer isomer shifts. Overall, the monitoring of the hyperfine parameters enables to correlate the changes in Na content to the individual Sn and Sb local chemical environments.« less

  6. Anisotropic giant magnetoresistance in NbSb?

    SciTech Connect (OSTI)

    Wang, Kefeng [Brookhaven National Lab. (BNL), Upton, NY (United States); Graf, D. [Florida State Univ., Tallahassee, FL (United States); Li, Lijun [Brookhaven National Lab. (BNL), Upton, NY (United States); Wang, Limin [Brookhaven National Lab. (BNL), Upton, NY (United States); Petrovic, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-12-05

    We report large transverse magnetoreistance (the magnetoresistant ratio ~ 1.3 10?% in 2 K and 9 T field, and 4.3 10?% in 0.4 K and 32 T field, without saturation) and field-induced metal semiconductor-like transition in NbSb?. Magnetoresistance is significantly suppressed but the metal-semiconductor-like transition persists when the current is along the ac-plane. The sign reversal of the Hall resistivity and Seebeck coefficient in the field, plus the electronic structure reveal the coexistence of a small number of holes with very high mobility and a large number of electrons with low mobility. The large MR is attributed to the change of the Fermi surface induced by the magnetic field in addition to the high mobility metal.

  7. Geology of offshore southern Namibia: Evidence from tectonic and basin-fill modeling based on modern seismic data

    SciTech Connect (OSTI)

    Houghton, M.L.; Peacock, D.N. )

    1993-09-01

    License 2815 is located offshore southern Namibia between Cape Dernberg and the South African border, approximately 50 km east of the 1974 Kudu gas discovery. Interactive workstation modeling of modern two-dimensional seismic data from the License area provides an improved understanding of the geology and tectonic history of this unexplored region. Although presently a broad submarine shelf influenced by late Cretaceous-Tertiary deltaic sedimentation from the Orange River, Interpretation based on modern seismic coverage has resulted in the recognition of a Late Jurassic-Early Cretaceous rift complex associated with the initial opening of the Atlantic Ocean. Geologic modeling suggests that a seismically-identified elongate rift localized along a major westward-dipping bounding fault may contain significant thicknesses of Neocomian( ) clastic sediments. Barremian-Aptian marine flooding of this area followed the rifting episode. Mixed marine and deltaic sedimentation has dominated the region since the middle Aptian. Palinspastic restorations of depth-converted seismic lines have helped to unravel the episodic tectonic history of rifting in this area. Input of geologic parameters, including relative sea level changes and sedimentation rates, has yielded computer-derived basin-fill models, which have in turn been integrated with the local tectonic model to make lithology predictions.

  8. Set the PACE St. Louis

    Broader source: Energy.gov [DOE]

    Commercial property owners, community associations (e.g., Home Owners Associations), and some residential property owners are eligible for Set the PACE St. Louis. Currently, only residential prop...

  9. Enhanced optical property in quaternary GaInAsSb/AlGaAsSb quantum wells

    SciTech Connect (OSTI)

    Lin, Chien-Hung Lee, Chien-Ping

    2014-10-21

    High quality GaInAsSb/AlGaAsSb quantum wells (QWs) have been grown by molecular beam epitaxy using proper interface treatments. By controlling the group-V elements at interfaces, we obtained excellent optical quality QWs, which were free from undesired localized trap states, which may otherwise severely affect the exciton recombination. Strong and highly efficient exciton emissions up to room temperature with a wavelength of 2.2 μm were observed. A comprehensive investigation on the QW quality was carried out using temperature dependent and power dependent photoluminescence (PL) measurements. The PL emission intensity remains nearly constant at low temperatures and is free from the PL quenching from the defect induced localized states. The temperature dependent emission energy had a bulk-like behavior, indicating high quality well/barrier interfaces. Because of the uniformity of the QWs and smooth interfaces, the low temperature limit of inhomogeneous line width broadening is as small as 5 meV.

  10. St Andrews Fuel Cells | Open Energy Information

    Open Energy Info (EERE)

    St Andrews Fuel Cells Place: Fife, Scotland, United Kingdom Product: A spin-out fuel cell company from the University of St Andrews to work on further prototypes of St Andrews'...

  11. St. Lucie Data Dashboard | Department of Energy

    Energy Savers [EERE]

    Data Dashboard St. Lucie Data Dashboard The data dashboard for St. Lucie, Florida, a partner in the Better Buildings Neighborhood Program. St. Lucie Data Dashboard (300.64 KB) More ...

  12. The reaction mechanism of SnSb and Sb thin film anodes for Na-ion batteries studied by X-ray diffraction, 119Sn and 121Sb Mössbauer spectroscopies

    SciTech Connect (OSTI)

    Baggetto, Loïc; Hah, Hien-Yoong; Jumas, Jean-Claude; Johnson, Charles E.; Johnson, Jacqueline A.; Keum, Jong K.; Bridges, Craig A.; Veith, Gabriel M.

    2014-06-01

    The electrochemical reaction of Sb and SnSb anode materials with Na results in the formation of amorphous materials. To understand the resulting phases and electrochemical capacities we studied the reaction products local order using 119Sn and 121Sb Mössbauer spectroscopies in conjunction with measurements performed on model powder compounds of Na-Sn and Na-Sb to further clarify the reactions steps. For pure Sb the discharge (sodiation) starts with the formation of an amorphous phase composed of atomic environments similar to those found in NaSb, and proceeds further by the formation of environments similar to that present in Na3Sb. The reversible reaction takes place during a large portion of the charge process. At full charge the anode material still contains a substantial fraction of Na, which explains the lack of recrystallization into crystalline Sb. The reaction of SnSb yields Na3Sb crystalline phase at full discharge at higher temperatures (65 and 95°C) while the room temperature reaction yields amorphous compounds. The electrochemically-driven, solid-state amorphization reaction occurring at room temperature is governed by the simultaneous formation of Na-coordinated Sn and Sb environments, as monitored by the decrease (increase) of the 119Sn (121Sb) Mössbauer isomer shifts. Overall, the monitoring of the hyperfine parameters enables to correlate the changes in Na content to the individual Sn and Sb local chemical environments.

  13. TANK 40 FINAL SB6 CHEMICAL CHARACTERIZATION RESULTS

    SciTech Connect (OSTI)

    Bannochie, C.

    2010-08-13

    A sample of Sludge Batch 6 (SB6) was taken from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS), and a portion of the sample was designated for SB6 processing studies. The SB6 WAPS sample was also analyzed for chemical composition including noble metals and fissile composition, and these results are reported here. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to DWPF as SB6. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB6 sample was transferred from the shipping container into a 4-L high density polyethylene vessel and solids were allowed to settle overnight. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 485 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples.

  14. Chemical ordering rather than random alloying in SbAs (Journal...

    Office of Scientific and Technical Information (OSTI)

    Chemical ordering rather than random alloying in SbAs Title: Chemical ordering rather than random alloying in SbAs Authors: Shoemaker, Daniel P. ; Chasapis, Thomas C. ; Do, Dat ; ...

  15. A new n-type half-Heusler thermoelectric material NbCoSb (Journal...

    Office of Scientific and Technical Information (OSTI)

    A new n-type half-Heusler thermoelectric material NbCoSb Citation Details In-Document Search Title: A new n-type half-Heusler thermoelectric material NbCoSb Highlights: * ...

  16. Quaternary InGaAsSb Thermophotovoltaic Diode Technology

    SciTech Connect (OSTI)

    M Dashiell; J Beausang; H Ehsani; G Nichols; D DePoy; L Danielson; P Talamo; K Rahner; E Brown; S Burger; P Fourspring; W Topper; P Baldasaro; C Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; Jizhong Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryl

    2005-01-26

    Thermophotovoltaic (TPV) diodes fabricated from InGaAsSb alloys lattice-matched to GaSb substrates are grown by Metal Organic Vapor Phase Epitaxy (MOVPE). 0.53eV InGaAsSb TPV diodes utilizing front-surface spectral control filters have been tested in a vacuum cavity and a TPV thermal-to-electric conversion efficiency ({eta}{sub TPV}) and a power density (PD) of {eta}{sub TPV} = 19% and PD=0.58 W/cm{sup 2} were measured for T{sub radiator} = 950 C and T{sub diode} = 27 C. Recombination coefficients deduced from minority carrier measurements and the theory reviewed in this article predict a practical limit to the maximum achievable conversion efficiency and power density for 0.53eV InGaAsSb TPV. The limits for the above operating temperatures are projected to be {eta}{sub TPV} = 26% and PD = 0.75 W/cm{sup 2}. These limits are extended to {eta}{sub TPV} = 30% and PD = 0.85W/cm{sup 2} if the diode active region is bounded by a reflective back surface to enable photon recycling and a two-pass optical path length. The internal quantum efficiency of the InGaAsSb TPV diode is close to the theoretically predicted limits, with the exception of short wavelength absorption in GaSb contact layers. Experiments show that the open circuit voltage of the 0.53eV InGaAsSb TPV diodes is not strongly dependent on the device architectures studied in this work where both N/P and P/N double heterostructure diodes have been grown with various acceptor and donor doping levels, having GaSb and AlGaAsSb confinement, and also partial back surface reflectors. Lattice matched InGaAsSb TPV diodes were fabricated with bandgaps ranging from 0.6 to 0.5eV without significant degradation of the open circuit voltage factor, quantum efficiency, or fill factor as the composition approached the miscibility gap. The key diode performance parameter which is limiting efficiency and power density below the theoretical limits in InGaAsSb TPV devices is the open circuit voltage. The open circuit voltages of

  17. SB Electronics Breaks Ground on New Factory | Department of Energy

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

    SB Electronics Breaks Ground on New Factory SB Electronics Breaks Ground on New Factory April 29, 2010 - 5:22pm Addthis U.S. Rep. Peter Welch (from left), Vermont Lt. Gov. Brian Dubie, SBE board member Win Hunter, SBE board chair Stan Fishkin, Assi U.S. Rep. Peter Welch (from left), Vermont Lt. Gov. Brian Dubie, SBE board member Win Hunter, SBE board chair Stan Fishkin, Assi Paul Lester Paul Lester Digital Content Specialist, Office of Public Affairs A Vermont company broke ground on a new

  18. Growth of Sb-Bi gradient single crystals

    SciTech Connect (OSTI)

    Kozhemyakin, G. N. Lutskiy, D. V.; Rom, M. A.; Mateychenko, P. V.

    2008-12-15

    The growth conditions and structural quality of Sb-Bi gradient single crystals with Bi content from 2 to 18 at %, grown by the Czochralski method with solid phase feed, are investigated. Bi distribution in the crystals along their pulling direction are studied by electron probe microanalysis and the change in the interplanar spacing is analyzed by double-crystal X-ray diffraction. It is established that the pulling rate and feed mass affect the Bi distribution in Sb-Bi single crystals.

  19. Structural transformations in amorphous ↔ crystalline phase change of Ga-Sb alloys

    SciTech Connect (OSTI)

    Edwards, T. G.; Sen, S.; Hung, I.; Gan, Z.; Kalkan, B.; Raoux, S.

    2013-12-21

    Ga-Sb alloys with compositions ranging between ∼12 and 50 at. % Ga are promising materials for phase change random access memory applications. The short-range structures of two such alloys with compositions Ga{sub 14}Sb{sub 86} and Ga{sub 46}Sb{sub 54} are investigated, in their amorphous and crystalline states, using {sup 71}Ga and {sup 121}Sb nuclear magnetic resonance spectroscopy and synchrotron x-ray diffraction. The Ga and Sb atoms are fourfold coordinated in the as-deposited amorphous Ga{sub 46}Sb{sub 54} with nearly 40% of the constituent atoms being involved in Ga-Ga and Sb-Sb homopolar bonding. This necessitates extensive bond switching and elimination of homopolar bonds during crystallization. On the other hand, Ga and Sb atoms are all threefold coordinated in the as-deposited amorphous Ga{sub 14}Sb{sub 86}. Crystallization of this material involves phase separation of GaSb domains in Sb matrix and a concomitant increase in the Ga coordination number from 3 to 4. Results from crystallization kinetics experiments suggest that the melt-quenching results in the elimination of structural “defects” such as the homopolar bonds and threefold coordinated Ga atoms in the amorphous phases of these alloys, thereby rendering them structurally more similar to the corresponding crystalline states compared to the as-deposited amorphous phases.

  20. St. Lucie County Summary of Reported Data

    Broader source: Energy.gov [DOE]

    Summary of data reported by Better Buildings Neighborhood Program partner St. Lucie County, Florida.

  1. Quaternary InGaAsSb Thermophotovoltaic Diodes

    SciTech Connect (OSTI)

    MW Dashiell; JF Beausang; H Ehsani; GJ Nichols; DM Depoy; LR Danielson; P Talamo; KD Rahner; EJ Brown; SR Burger; PM Foruspring; WF Topper; PF Baldasaro; CA Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; J Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryi

    2006-03-09

    In{sub x}Ga{sub 1-x}As{sub y}Sb{sub 1-y} thermophotovoltaic (TPV) diodes were grown lattice-matched to GaSb substrates by Metal Organic Vapor Phase Epitaxy (MOVPE) in the bandgap range of E{sub G} = 0.5 to 0.6eV. InGaAsSb TPV diodes, utilizing front-surface spectral control filters, are measured with thermal-to-electric conversion efficiency and power density of {eta}{sub TPV} = 19.7% and PD =0.58 W/cm{sup 2} respectively for a radiator temperature of T{sub radiator} = 950 C, diode temperature of T{sub diode} = 27 C, and diode bandgap of E{sub G} = 0.53eV. Practical limits to TPV energy conversion efficiency are established using measured recombination coefficients and optical properties of front surface spectral control filters, which for 0.53eV InGaAsSb TPV energy conversion is {eta}{sub TPV} = 28% and PD = 0.85W/cm{sup 2} at the above operating temperatures. The most severe performance limits are imposed by (1) diode open-circuit voltage (VOC) limits due to intrinsic Auger recombination and (2) parasitic photon absorption in the inactive regions of the module. Experimentally, the diode V{sub OC} is 15% below the practical limit imposed by intrinsic Auger recombination processes. Analysis of InGaAsSb diode electrical performance vs. diode architecture indicate that the V{sub OC} and thus efficiency is limited by extrinsic recombination processes such as through bulk defects.

  2. TANK 40 FINAL SB7B CHEMICAL CHARACTERIZATION RESULTS

    SciTech Connect (OSTI)

    Bannochie, C.

    2012-03-15

    A sample of Sludge Batch 7b (SB7b) was taken from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). The SB7b WAPS sample was also analyzed for chemical composition including noble metals and fissile constituents, and these results are reported here. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to the Defense Waste Processing Facility (DWPF) as SB7b. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB7b sample was transferred from the shipping container into a 4-L high density polyethylene bottle and solids were allowed to settle over the weekend. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 558 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon{reg_sign} vessels and four with NaOH/Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Two Analytical Reference Glass - 1 (ARG-1) standards were digested along with a blank for each preparation. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma - atomic emission spectroscopy (ICP-AES) analysis, inductively coupled plasma - mass spectrometry (ICP-MS) analysis, atomic absorption spectroscopy (AA) for As and Se, and cold vapor atomic absorption spectroscopy (CV-AA) for Hg. Equivalent dilutions of the alkali fusion digestions and blank were submitted to AD for ICP-AES analysis. Tank 40 SB7b supernate was collected from a mixed slurry sample in the SRNL Shielded Cells and submitted to AD for ICP-AES, ion chromatography (IC), total base

  3. Magnetic properties of MnSb inclusions formed in GaSb matrix directly during molecular beam epitaxial growth

    SciTech Connect (OSTI)

    Lawniczak-Jablonska, Krystyna; Wolska, Anna; Klepka, Marcin T.; Kret, Slawomir; Kurowska, Boguslawa; Kowalski, Bogdan J.; Twardowski, Andrzej; Wasik, Dariusz; Kwiatkowski, Adam; Sadowski, Janusz

    2011-04-01

    Despite of intensive search for the proper semiconductor base materials for spintronic devices working at room temperature no appropriate material based on ferromagnetic semiconductors has been found so far. We demonstrate that the phase segregated system with MnSb hexagonal inclusions inside the GaSb matrix, formed directly during the molecular beam epitaxial growth reveals the ferromagnetic properties at room temperature and is a good candidate for exploitation in spintronics. Furthermore, the MnSb inclusions with only one crystalline structure were identified in this GaMn:MnSb granular material. The SQUID magnetometry confirmed that this material exhibits ferromagnetic like behavior starting from helium up to room temperature. Moreover, the magnetic anisotropy was found which was present also at room temperature, and it was proved that by choosing a proper substrate it is possible to control the direction of easy axis of inclusions' magnetization moment between in-plane and out-of-plane; the latter is important in view of potential applications in spintronic devices.

  4. Influence of substituting Sn for Sb on the thermoelectric transport properties of CoSb{sub 3}-based skutterudites

    SciTech Connect (OSTI)

    Hui, Si; Nielsen, Michele D.; Homer, Mark R.; Medlin, Douglas L.; Tobola, Janusz; Salvador, James R.; Heremans, Joseph P.; Pipe, Kevin P.; Uher, Ctirad

    2014-03-14

    Band structure calculations that incorporate impurity effects suggest that a band resonant state may be formed in p-type CoSb{sub 3}-based skutterudites by replacing Sb atoms with Sn dopant atoms. Such resonant states have the potential to greatly improve thermoelectric energy conversion efficiency by increasing the density of states variation near the Fermi level, thereby increasing the Seebeck coefficient at a given carrier concentration. Through transport measurements of the Seebeck coefficient, electrical conductivity, thermal conductivity, and Hall coefficient, we show that a practical band resonant state is not achieved by Sn doping. Compared to undoped CoSb{sub 3}, the dimensionless figure of merit (ZT) in Sn-doped CoSb{sub 3} is enhanced slightly at high temperatures to a value of 0.2, mostly due to a reduction in thermal conductivity. The Fermi level is calculated not to reach the band resonant state induced by Sn impurity atoms within the range of Sn concentrations examined here.

  5. Electronic structures of [001]- and [111]-oriented InSb and GaSb free-standing nanowires

    SciTech Connect (OSTI)

    Liao, Gaohua; Luo, Ning; Yang, Zhihu; Chen, Keqiu; Xu, H. Q. E-mail: hongqi.xu@ftf.lth.se

    2015-09-07

    We report on a theoretical study of the electronic structures of InSb and GaSb nanowires oriented along the [001] and [111] crystallographic directions. The nanowires are described by atomistic, tight-binding models, including spin-orbit interaction. The band structures and the wave functions of the nanowires are calculated by means of a Lanczos iteration algorithm. For the [001]-oriented InSb and GaSb nanowires, the systems with both square and rectangular cross sections are considered. Here, it is found that all the energy bands are doubly degenerate. Although the lowest conduction bands in these nanowires show good parabolic dispersions, the top valence bands show rich and complex structures. In particular, the topmost valence bands of the nanowires with a square cross section show a double maximum structure. In the nanowires with a rectangular cross section, this double maximum structure is suppressed, and the top valence bands gradually develop into parabolic bands as the aspect ratio of the cross section is increased. For the [111]-oriented InSb and GaSb nanowires, the systems with hexagonal cross sections are considered. It is found that all the bands at the Γ-point are again doubly degenerate. However, some of them will split into non-degenerate bands when the wave vector moves away from the Γ-point. Although the lowest conduction bands again show good parabolic dispersions, the topmost valence bands do not show the double maximum structure. Instead, they show a single maximum structure with its maximum at a wave vector slightly away from the Γ-point. The wave functions of the band states near the band gaps of the [001]- and [111]-oriented InSb and GaSb nanowires are also calculated and are presented in terms of probability distributions in the cross sections. It is found that although the probability distributions of the band states in the [001]-oriented nanowires with a rectangular cross section could be qualitatively described by one-band effective

  6. St. Louis FUSRAP Lessons Learned

    SciTech Connect (OSTI)

    Eberlin, J.; Williams, D.; Mueller, D.

    2003-02-26

    The purpose of this paper is to present lessons learned from fours years' experience conducting Remedial Investigation and Remedial Action activities at the St. Louis Downtown Site (SLDS) under the Formerly Utilized Sites Remedial Action Program (FUSRAP). Many FUSRAP sites are experiencing challenges conducting Remedial Actions within forecasted volume and budget estimates. The St. Louis FUSRAP lessons learned provide insight to options for cost effective remediation at FUSRAP sites. The lessons learned are focused on project planning (budget and schedule), investigation, design, and construction.

  7. St. Lucie County, Florida: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hutchinson Island South, Florida Indian River Estates, Florida Lakewood Park, Florida Port St. Lucie, Florida Port St. Lucie-River Park, Florida St. Lucie Village, Florida White...

  8. St. Charles County, Missouri: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Missouri O'Fallon, Missouri Portage Des Sioux, Missouri St. Charles, Missouri St. Paul, Missouri St. Peters, Missouri Weldon Spring Heights, Missouri Weldon Spring, Missouri...

  9. GaSb substrates with extended IR wavelength for advanced space based applications

    SciTech Connect (OSTI)

    Allen, Lisa P.; Flint, Patrick; Dallas, Gordon; Bakken, Daniel; Blanchat, Kevin; Brown, Gail J.; Vangala, Shivashankar R.; Goodhue, William D.; Krishnaswami, Kannan

    2009-05-01

    GaSb substrates have advantages that make them attractive for implementation of a wide range of infrared (IR) detectors with higher operating temperatures for stealth and space based applications. A significant aspect that would enable widespread commercial application of GaSb wafers for very long wavelength IR (VLWIR) applications is the capability for transmissivity beyond 15 m. Due largely to the GaSb (antisite) defect and other point defects in undoped GaSb substrates, intrinsic GaSb is still slightly p-type and strongly absorbs in the VLWIR. This requires backside thinning of the GaSb substrate for IR transmissivity. An extremely low n-type GaSb substrate is preferred to eliminate thinning and provide a substrate solution for backside illuminated VLWIR devices. By providing a more homogeneous radial distribution of the melt solute to suppress GaSb formation and controlling the cooling rate, ultra low doped n:GaSb has been achieved. This study examines the surface properties and IR transmission spectra of ultra low doped GaSb substrates at both room and low temperatures. Atomic force microscopy (AFM), homoepitaxy by MBE, and infrared Fourier transform (FTIR) analysis was implemented to examine material quality. As compared with standard low doped GaSb, the ultra low doped substrates show over 50% transmission and consistent wavelength transparency past 23 m with improved %T at low temperature. Homoepitaxy and AFM results indicate the ultra low doped GaSb has a low thermal desorbtion character and qualified morphology. In summary, improvements in room temperature IR transmission and extended wavelength characteristics have been shown consistently for ultra low doped n:GaSb substrates.

  10. Phase transitions in Ge-Sb phase change materials

    SciTech Connect (OSTI)

    Raoux, Simone; Virwani, Kumar; Hitzbleck, Martina; Salinga, Martin; Madan, Anita; Pinto, Teresa L.

    2009-03-15

    Thin films of the phase change material Ge-Sb with Ge concentrations between 7.3 and 81.1 at. % were deposited by cosputtering from elemental targets. Their crystallization behavior was studied using time-resolved x-ray diffraction, Auger electron spectroscopy, differential scanning calorimetry, x-ray reflectivity, profilometry, optical reflectivity, and resistivity versus temperature measurements. It was found that the crystallization temperature increases with Ge content. Calculations of the glass transition temperature (which is a lower limit for the crystallization temperature T{sub x}) also show an increase with Ge concentration closely tracking the measured values of T{sub x}. For low Ge content samples, Sb x-ray diffraction peaks occurred during a heating ramp at lower temperature than Ge diffraction peaks. The appearance of Ge peaks is related to Ge precipitation and agglomeration. For Ge concentrations of 59.3 at. % and higher, Sb and Ge peaks occurred at the same temperature. Upon crystallization, film mass density and optical reflectivity increase as well as electrical contrast (ratio of resistivity in amorphous phase to crystalline phase) all showed a maximum for the eutectic alloy (14.5 at. % Ge). For the alloy with 59.3 at. % Ge there was very little change in any of these parameters, while the alloy with 81.1 at. % Ge behaved opposite to a typical phase change alloy and showed reduced mass density and reflectivity and increased resistivity.

  11. Short-wave infrared barriode detectors using InGaAsSb absorption material lattice matched to GaSb

    SciTech Connect (OSTI)

    Craig, A. P.; Percy, B.; Marshall, A. R. J.; Jain, M.; Wicks, G.; Hossain, K.; Golding, T.; McEwan, K.; Howle, C.

    2015-05-18

    Short-wave infrared barriode detectors were grown by molecular beam epitaxy. An absorption layer composition of In{sub 0.28}Ga{sub 0.72}As{sub 0.25}Sb{sub 0.75} allowed for lattice matching to GaSb and cut-off wavelengths of 2.9 μm at 250 K and 3.0 μm at room temperature. Arrhenius plots of the dark current density showed diffusion limited dark currents approaching those expected for optimized HgCdTe-based detectors. Specific detectivity figures of around 7×10{sup 10} Jones and 1×10{sup 10} Jones were calculated, for 240 K and room temperature, respectively. Significantly, these devices could support focal plane arrays working at higher operating temperatures.

  12. GaInP semiconductor compounds doped with the Sb isovalent impurity

    SciTech Connect (OSTI)

    Skachkov, A. F.

    2015-05-15

    GaInP{sub 1−x}Sb{sub x} layers containing different Sb fractions are produced by metal-organic vaporphase epitaxy on GaAs and Ge substrates. The charge-carrier mobilities in the GaInP{sub 1−x}Sb{sub x} layers are measured at room temperature and 77 K. The room-temperature charge-carrier mobilities in the GaInP{sub 1−x}Sb{sub x} layers additionally doped with donor and acceptor impurities are measured. The photoluminescence peaks of GaInP{sub 1−x}Sb{sub x} are detected. The influence of the Sb impurity on the band gap and charge-carrier mobility in GaInP is determined.

  13. Ab initio study of structural, electronic, magnetic alloys: XTiSb (X = Co, Ni and Fe)

    SciTech Connect (OSTI)

    Ibrir, M. Berri, S.; Lakel, S.; Alleg, S.; Bensalem, R.

    2015-03-30

    Structural, electronic and magnetic properties of three semi-Heusler compounds of CoTiSb, NiTiSb and FeTiSb were calculated by the method (FP-LAPW) which is based on the DFT code WIEN2k. We used the generalized gradient approximation (GGA (06)) for the term of the potential exchange and correlation (XC) to calculate structural properties, electronic properties and magnetic properties. Structural properties obtained as the lattice parameter are in good agreement with the experimental results available for the electronic and magnetic properties was that: CoTiSb is a semiconductor NiTiSb is a metal and FeTiSb is a half-metal ferromagnetic.

  14. Comparative analysis of hole transport in compressively strained InSb and Ge quantum well heterostructures

    SciTech Connect (OSTI)

    Agrawal, Ashish; Barth, Michael; Madan, Himanshu; Datta, Suman; Lee, Yi-Jing; Lin, You-Ru; Wu, Cheng-Hsien; Ko, Chih-Hsin; Wann, Clement H.; Loubychev, Dmitri; Liu, Amy; Fastenau, Joel; Lindemuth, Jeff

    2014-08-04

    Compressively strained InSb (s-InSb) and Ge (s-Ge) quantum well heterostructures are experimentally studied, with emphasis on understanding and comparing hole transport in these two-dimensional confined heterostructures. Magnetotransport measurements and bandstructure calculations indicate 2.5 lower effective mass for s-InSb compared to s-Ge quantum well at 1.9??10{sup 12}?cm{sup 2}. Advantage of strain-induced m* reduction is negated by higher phonon scattering, degrading hole transport at room temperature in s-InSb quantum well compared to s-Ge heterostructure. Consequently, effective injection velocity is superior in s-Ge compared to s-InSb. These results suggest s-Ge quantum well heterostructure is more favorable and promising p-channel candidate compared to s-InSb for future technology node.

  15. Science in St. Louis - Dr. Christine Kirmaier | Photosynthetic Antenna

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

    Research Center in St. Louis - Dr. Christine Kirmaier Science in St. Louis - Dr. Christine Kirmaier

  16. Chemical ordering rather than random alloying in SbAs (Journal...

    Office of Scientific and Technical Information (OSTI)

    Title: Chemical ordering rather than random alloying in SbAs Authors: Shoemaker, Daniel P. ; Chasapis, Thomas C. ; Do, Dat ; Francisco, Melanie C. ; Chung, Duck Young ; Mahanti, S. ...

  17. Method of making AlInSb by metal-organic chemical vapor deposition

    DOE Patents [OSTI]

    Biefeld, Robert M. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Baucom, Kevin C. (Albuquerque, NM)

    2000-01-01

    A method for producing aluminum-indium-antimony materials by metal-organic chemical vapor deposition (MOCVD). This invention provides a method of producing Al.sub.X In.sub.1-x Sb crystalline materials by MOCVD wherein an Al source material, an In source material and an Sb source material are supplied as a gas to a heated substrate in a chamber, said Al source material, In source material, and Sb source material decomposing at least partially below 525.degree. C. to produce Al.sub.x In.sub.1-x Sb crystalline materials wherein x is greater than 0.002 and less than one.

  18. ST

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

    Safety Monitoring Program) Meeting in China, December 9-14, 2009 Respectfully ... Rick Savercool and Keith Rule - U.S. JWG to China Reviewed by: Prof. Huang and Dr. ...

  19. High-temperature luminescence in an n-GaSb/n-InGaAsSb/p-AlGaAsSb light-emitting heterostructure with a high potential barrier

    SciTech Connect (OSTI)

    Petukhov, A. A., E-mail: andrey-rus29@rambler.ru; Zhurtanov, B. E.; Kalinina, K. V.; Stoyanov, N. D.; Salikhov, H. M.; Mikhailova, M. P.; Yakovlev, Yu. P. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)] [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2013-09-15

    The electroluminescent properties of an n-GaSb/n-InGaAsSb/p-AlGaAsSb heterostructure with a high potential barrier in the conduction band (large conduction-band offset) at the n-GaSb/n-InGaAsSb type-II heterointerface ({Delta}E{sub c} = 0.79 eV) are studied. Two bands with peaks at 0.28 and 0.64 eV at 300 K, associated with radiative recombination in n-InGaAsSb and n-GaSb, respectively, are observed in the electroluminescence (EL) spectrum. In the entire temperature range under study, T = 290-480 K, additional electron-hole pairs are formed in the n-InGaAsSb active region by impact ionization with hot electrons heated as a result of the conduction-band offset. These pairs contribute to radiative recombination, which leads to a nonlinear increase in the EL intensity and output optical power with increasing pump current. A superlinear increase in the emission power of the long-wavelength band is observed upon heating in the temperature range T = 290-345 K, and a linear increase is observed at T > 345 K. This work for the first time reports an increase in the emission power of a light-emitting diode structure with increasing temperature. It is shown that this rise is caused by a decrease in the threshold energy of the impact ionization due to narrowing of the band gap of the active region.

  20. Probing the mechanism of sodium ion insertion into copper antimony Cu2Sb anodes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baggetto, Loic; Carroll, Kyler J.; Hah, Hien -Yoong; Johnson, Charles E.; Mullins, David R.; Unocic, Raymond R.; Johnson, Jacqueline A.; Meng, Ying Shirley; Veith, Gabriel M.

    2014-03-25

    Cycling Cu2Sb films with fluoroethylene carbonate additive drastically improves the capacity retention of the electrode compared to cycling in pure PC with about 250 mAh g-1 retained capacity for about two hundred cycles. TEM photographs reveal that the pristine films are formed of nanoparticles of 5-20 nm diameters. XRD results highlight that during the first discharge the reaction leads to the formation of Na3Sb via an intermediate amorphous phase. During charge, Na3Sb crystallites convert into an amorphous phase, which eventually crystallizes into Cu2Sb at full charge, indicating a high degree of structural reversibility. The subsequent discharge is marked by amore » new plateau around 0.5 V at low Na/Sb content which does not correspond to the formation of a crystalline phase. XAS data show that the fully discharged electrode material has interatomic distances matching those expected for the coexistence of Cu and Na3Sb nanodomains. At 1 V charge, the structure somewhat differs from that of Cu2Sb whereas at 2 V charge, when all Na is removed, the structure is significantly closer to that of the starting material. 121Sb Mössbauer spectroscopy isomer shifts of Cu2Sb powder (-9.67 mm s-1) and thin films (-9.65 mm s-1) are reported for the first time, and agree with the value predicted theoretically. At full discharge, an isomer shift (-8.10 mm s-1) rather close to that of a Na3Sb reference powder (-8.00 mm s-1) is measured, in agreement with the formation of Na3Sb domains evidenced by XRD and XAS data. As a result, the isomer shift at 1 V charge (-9.29 mm s-1) is close to that of the pristine material and the higher value is in agreement with the lack of full desodiation at 1 V.« less

  1. The reaction mechanism of FeSb2 as anode for sodium-ion batteries

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baggetto, Loic; Hah, Hien-Yoong; Charles E. Johnson; Bridges, Craig A.; Johnson, Jackie A.; Veith, Gabriel M.

    2014-04-04

    The electrochemical reaction of FeSb2 with Na is reported for the first time. The first discharge (sodiation) potential profile of FeSb2 is characterized by a gentle slope centered at 0.25 V. During charge (Na removal) and the subsequent discharge, the main reaction takes place near 0.7 V and 0.4 V, respectively. The reversible storage capacity amounts to 360 mA h g-1, which is smaller than the theoretical value of 537 mA h g-1. The reaction, studied by ex situ and in situ X-ray diffraction, is found to proceed by the consumption of crystalline FeSb2 to form an amorphous phase. Uponmore » further sodiation, the formation of nanocrystalline Na3Sb domains is evidenced. During desodiation, Na3Sb domains convert into an amorphous phase. The chemical environment of Fe, probed by 57Fe Mo ssbauer spectroscopy, undergoes significant changes during the reaction. During sodiation, the well-resolved doublet of FeSb2 with an isomer shift around 0.45 mm s-1 and a quadrupole splitting of 1.26 mm s-1 is gradually converted into a doublet line centered at about 0.15 mm s1 along with a singlet line around 0 mm s-1. The former signal results from the formation of a Fe-rich FexSb alloy with an estimated composition of Fe4Sb while the latter signal corresponds to superparamagnetic Fe due to the formation of nanosized pure Fe domains. Interestingly the signal of Fe4Sb remains unaltered during desodiation. This mechanism is substantially different than that observed during the reaction with Li. The irreversible formation of a Fe-rich Fe4Sb alloy and the absence of full desodiation of Sb domains explain the lower than theoretical practical storage capacity.« less

  2. Probing the Mechanism of Sodium Ion Insertion into Copper Antimony Cu2 Sb Anodes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baggetto, Loïc; Carroll, Kyler J.; Hah, Hien-Yoong; Johnson, Charles E.; Mullins, David R.; Unocic, Raymond R.; Johnson, Jacqueline A.; Meng, Ying Shirley; Veith, Gabriel M.

    2014-03-25

    Cycling Cu2Sb films with fluoroethylene carbonate additive drastically improves the capacity retention of the electrode compared to cycling in pure PC with about 250 mAh g-1 retained capacity for about two hundred cycles. TEM photographs reveal that the pristine films are formed of nanoparticles of 5-20 nm diameters. XRD results highlight that during the first discharge the reaction leads to the formation of Na3Sb via an intermediate amorphous phase. During charge, Na3Sb crystallites convert into an amorphous phase, which eventually crystallizes into Cu2Sb at full charge, indicating a high degree of structural reversibility. The subsequent discharge is marked by amore » new plateau around 0.5 V at low Na/Sb content which does not correspond to the formation of a crystalline phase. XAS data show that the fully discharged electrode material has interatomic distances matching those expected for the coexistence of Cu and Na3Sb nanodomains. At 1 V charge, the structure somewhat differs from that of Cu2Sb whereas at 2 V charge, when all Na is removed, the structure is significantly closer to that of the starting material. 121Sb Mössbauer spectroscopy isomer shifts of Cu2Sb powder (-9.67 mm s-1) and thin films (-9.65 mm s-1) are reported for the first time, and agree with the value predicted theoretically. At full discharge, an isomer shift (-8.10 mm s-1) rather close to that of a Na3Sb reference powder (-8.00 mm s-1) is measured, in agreement with the formation of Na3Sb domains evidenced by XRD and XAS data. The isomer shift at 1 V charge (-9.29 mm s-1) is close to that of the pristine material and the higher value is in agreement with the lack of full desodiation at 1 V.« less

  3. Temperature dependence of the dielectric response of AlSb

    SciTech Connect (OSTI)

    Jung, Y. W.; Kim, T. J.; Kim, Y. D.; Shin, S. H.; Kim, S. Y.; Song, J. D.

    2011-12-23

    Spectroscopic ellipometry was used to determine the optical response of an intrinsic AlSb film as a function of temperature. The 1.5 {mu}m thick film was grown on a (001) GaAs substrate by molecular beam epitaxy. Measurements were done at temperatures from 300 K to the growth temperature of 800 K over a spectral range of 0.7 to 5.0 eV. To avoid oxidation artifacts, measurements were done with the film in situ. The data were analyzed using a parametric semiconductor model for its temperature dependence.

  4. Tank 40 Final SB7b Chemical Characterization Results

    SciTech Connect (OSTI)

    Bannochie, C. J.

    2012-11-06

    A sample of Sludge Batch 7b (SB7b) was taken from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). The SB7b WAPS sample was also analyzed for chemical composition including noble metals and fissile constituents. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB7b sample was transferred from the shipping container into a 4-L high density polyethylene bottle and solids were allowed to settle over the weekend. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 558 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon? vessels and four with NaOH/Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Two Analytical Reference Glass ? 1 (ARG-1) standards were digested along with a blank for each preparation. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma ? atomic emission spectroscopy (ICP-AES) analysis, inductively coupled plasma ? mass spectrometry (ICP-MS) analysis, atomic absorption spectroscopy (AA) for As and Se, and cold vapor atomic absorption spectroscopy (CV-AA) for Hg. Equivalent dilutions of the alkali fusion digestions and blank were submitted to AD for ICP-AES analysis. Tank 40 SB7b supernate was collected from a mixed slurry sample in the SRNL Shielded Cells and submitted to AD for ICP-AES, ion chromatography (IC), total base/free OH{sup -}/other base, total inorganic carbon/total organic carbon (TIC/TOC) analyses, and Cs-137 gamma scan. Weighted dilutions of slurry were submitted for IC, TIC/TOC, and total base/free OH-/other base analyses. Activities for U-233, U-235

  5. Florida Nuclear Profile - St Lucie

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

    St Lucie" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer capacity factor (percent)","Type","Commercial operation date","License expiration date" 1,839,"5,299",72.1,"PWR","application/vnd.ms-excel","application/vnd.ms-excel" 2,839,"7,331",99.7,"PWR","application/vnd.ms-excel","application/vnd.ms-excel"

  6. Spintronic properties of Li1.5Mn0.5Z (Z=As, Sb) compounds in...

    Office of Scientific and Technical Information (OSTI)

    Publisher's Accepted Manuscript: Spintronic properties of Li1.5Mn0.5Z (ZAs, Sb) compounds in the Cu2Sb structure This content will become publicly available on January 26, 2017 ...

  7. Interface Reactions and Electrical Characteristics of Au/GaSb Contacts

    SciTech Connect (OSTI)

    H. Ehsani; R.J. Gutmann; G.W. Charache

    2000-07-07

    The reaction of Au with GaSb occurs at a relatively low temperature (100 C). Upon annealing, a AuSb{sub 2} compound and several Au-Ga phases are produced. Phase transitions occur toward higher Ga concentration with increasing annealing temperatures. Furthermore, the depth of the contact also increases with increased annealing temperature. They found that the AuSb{sub 2} compound forms on the GaSb surface, with the compound crystal partially ordered with respect to the substrate. The transition of Schottky- to ohmic-contact behavior in Au/n-type GaSb occurs simultaneously with the formation of the AuGa compound at about a 250 C annealing temperature. This ohmic contact forms without the segregation of dopants at the metallic compound/GaSb interface. Therefore it is postulated that transition from Schottky- to ohmic-contact behavior is obtained through a series of tunneling transitions of electrons through defects in the depletion region in the Au/n-type GaSb contacts. Contact resistivities of 6-7 x 10{sup -6} {Omega}-cm{sup 2} were obtained with the annealing temperature between 300 and 350 C for 30 seconds. In Au/p-type GaSb contacts, the resistivity was independent of the annealing temperature. This suggested that the carrier transport in p-type contact dominated by thermionic emission.

  8. Facile synthesis of one-dimensional peapod-like Sb@C submicron-structures

    SciTech Connect (OSTI)

    Luo, W; Lorger, S; Wang, B; Bommier, C; Ji, XL

    2014-01-01

    We demonstrate a novel synthetic route to fabricate a one-dimensional peapod-like Sb@C structure with disperse Sb submicron-particles encapsulated in carbon submicron-tubes. The synthetic route may well serve as a general methodology for fabricating carbon/metallic fine structures by thermally reducing their carbon-coated metal oxide composites.

  9. In-situ crystallization of GeTe\\GaSb phase change memory stacked films

    SciTech Connect (OSTI)

    Velea, A.; Borca, C. N.; Grolimund, D.; Socol, G.; Galca, A. C.; Popescu, M.; Bokhoven, J. A. van

    2014-12-21

    Single and double layer phase change memory structures based on GeTe and GaSb thin films were deposited by pulsed laser deposition (PLD). Their crystallization behavior was studied using in-situ synchrotron techniques. Electrical resistance vs. temperature investigations, using the four points probe method, showed transition temperatures of 138 °C and 198 °C for GeTe and GaSb single films, respectively. It was found that after GeTe crystallization in the stacked films, Ga atoms from the GaSb layer diffused in the vacancies of the GeTe crystalline structure. Therefore, the crystallization temperature of the Sb-rich GaSb layer is decreased by more than 30 °C. Furthermore, at 210 °C, the antimony excess from GaSb films crystallizes as a secondary phase. At higher annealing temperatures, the crystalline Sb phase increased on the expense of GaSb crystalline phase which was reduced. Extended X-ray absorption fine structure (EXAFS) measurements at the Ga and Ge K-edges revealed changes in their local atomic environments as a function of the annealing temperature. Simulations unveil a tetrahedral configuration in the amorphous state and octahedral configuration in the crystalline state for Ge atoms, while Ga is four-fold coordinated in both as-deposited and annealed samples.

  10. Development of an electronic device quality aluminum antimonide (AlSb) semiconductor for solar cell applications

    SciTech Connect (OSTI)

    Sherohman, John W; Yee, Jick Hong; Combs, III, Arthur W

    2014-11-11

    Electronic device quality Aluminum Antimonide (AlSb)-based single crystals produced by controlled atmospheric annealing are utilized in various configurations for solar cell applications. Like that of a GaAs-based solar cell devices, the AlSb-based solar cell devices as disclosed herein provides direct conversion of solar energy to electrical power.

  11. Pennsylvania's 1st congressional district: Energy Resources ...

    Open Energy Info (EERE)

    in Pennsylvania's 1st congressional district PECO Energy Co Retrieved from "http:en.openei.orgwindex.php?titlePennsylvania%27s1stcongressionaldistrict&oldid198299...

  12. California's 31st congressional district: Energy Resources |...

    Open Energy Info (EERE)

    in California's 31st congressional district Angeleno Group Retrieved from "http:en.openei.orgwindex.php?titleCalifornia%27s31stcongressionaldistrict&oldid181523...

  13. Connecticut's 1st congressional district: Energy Resources |...

    Open Energy Info (EERE)

    1st congressional district Aztech Engineers Connecticut Light and Power Infinity Fuel Cell and Hydrogen Inc LiquidPiston Inc Nxegen SmartPower United Technologies Corp...

  14. St. Paul Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    USA Biomass National Map Retrieved from "http:en.openei.orgwindex.php?titleSt.PaulBiomassFacility&oldid398161" Feedback Contact needs updating Image needs updating...

  15. Green St Energy | Open Energy Information

    Open Energy Info (EERE)

    Green St. Energy Place: Tehachapi, California Zip: 93561 Sector: Wind energy Product: California-based OTC-quoted wind energy project developer. Coordinates: 35.132245,...

  16. California's 21st congressional district: Energy Resources |...

    Open Energy Info (EERE)

    can help OpenEI by expanding it. This page represents a congressional district in California. Registered Energy Companies in California's 21st congressional district Agrimass...

  17. California's 41st congressional district: Energy Resources |...

    Open Energy Info (EERE)

    can help OpenEI by expanding it. This page represents a congressional district in California. Registered Energy Companies in California's 41st congressional district BCL...

  18. Mount St. Mary's Abbey | Open Energy Information

    Open Energy Info (EERE)

    Energy Developments Energy Purchaser Mount St. Mary's Abbey Location Wrentham MA Coordinates 42.033096, -71.393711 Show Map Loading map... "minzoom":false,"mappings...

  19. City of St. George- Net Metering

    Broader source: Energy.gov [DOE]

    The City of St. George Energy Services Department (SGESD) offers a net metering program to its customers, and updated program guidelines and fees in September 2015.* 

  20. Ab initio calculation of the thermodynamic properties of InSb under intense laser irradiation

    SciTech Connect (OSTI)

    Feng, ShiQuan; Cheng, XinLu; Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Sichuan University, Chengdu, 610064 ; Zhao, JianLing; Zhang, Hong

    2013-07-28

    In this paper, phonon spectra of InSb at different electronic temperatures are presented. Based on the phonon dispersion relationship, we further perform a theoretical investigation of the thermodynamic properties of InSb under intense laser irradiation. The phonon entropy, phonon heat capacity, and phonon contribution to Helmholtz free energy and internal energy of InSb are calculated as functions of temperature at different electronic temperatures. The abrupt change in the phonon entropy- temperature curve from T{sub e} = 0.75 to 1.0 eV provides an indication of InSb undergoing a phase transition from solid to liquid. It can be considered as a collateral evidence of non-thermal melting for InSb under intense electronic excitation effect.

  1. Illinois SB 1987: the Clean Coal Portfolio Standard Law

    SciTech Connect (OSTI)

    2009-01-15

    On January 12, 2009, Governor Rod Blagojevich signed SB 1987, the Clean Coal Portfolio Standard Law. The legislation establishes emission standards for new coal-fueled power plants power plants that use coal as their primary feedstock. From 2009-2015, new coal-fueled power plants must capture and store 50 percent of the carbon emissions that the facility would otherwise emit; from 2016-2017, 70 percent must be captured and stored; and after 2017, 90 percent must be captured and stored. SB 1987 also establishes a goal of having 25 percent of electricity used in the state to come from cost-effective coal-fueled power plants that capture and store carbon emissions by 2025. Illinois is the first state to establish a goal for producing electricity from coal-fueled power plants with carbon capture and storage (CCS). To support the commercial development of CCS technology, the legislation guarantees purchase agreements for the first Illinois coal facility with CCS technology, the Taylorville Energy Center (TEC); Illinois utilities are required to purchase at least 5 percent of their electricity supply from the TEC, provided that customer rates experience only modest increases. The TEC is expected to be completed in 2014 with the ability to capture and store at least 50 percent of its carbon emissions.

  2. DWPF SIMULANT CPC STUDIES FOR SB7B

    SciTech Connect (OSTI)

    Koopman, D.

    2011-11-01

    Lab-scale DWPF simulations of Sludge Batch 7b (SB7b) processing were performed. Testing was performed at the Savannah River National Laboratory - Aiken County Technology Laboratory (SRNL-ACTL). The primary goal of the simulations was to define a likely operating window for acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT). In addition, the testing established conditions for the SRNL Shielded Cells qualification simulation of SB7b-Tank 40 blend, supported validation of the current glass redox model, and validated the coupled process flowsheet at the nominal acid stoichiometry. An acid window of 105-140% by the Koopman minimum acid (KMA) equation (107-142% DWPF Hsu equation) worked for the sludge-only flowsheet. Nitrite was present in the SRAT product for the 105% KMA run at 366 mg/kg, while SME cycle hydrogen reached 94% of the DWPF Slurry Mix Evaporator (SME) cycle limit in the 140% KMA run. The window was determined for sludge with added caustic (0.28M additional base, or roughly 12,000 gallons 50% NaOH to 820,000 gallons waste slurry). A suitable processing window appears to be 107-130% DWPF acid equation for sludge-only processing allowing some conservatism for the mapping of lab-scale simulant data to full-scale real waste processing including potentially non-conservative noble metal and mercury concentrations. This window should be usable with or without the addition of up to 7,000 gallons of caustic to the batch. The window could potentially be wider if caustic is not added to SB7b. It is recommended that DWPF begin processing SB7b at 115% stoichiometry using the current DWPF equation. The factor could be increased if necessary, but changes should be made with caution and in small increments. DWPF should not concentrate past 48 wt.% total solids in the SME cycle if moderate hydrogen generation is occurring simultaneously. The coupled flowsheet simulation made more hydrogen in the SRAT and SME cycles than the sludge-only run with the

  3. Effect of arsenic on the optical properties of GaSb-based type II quantum wells with quaternary GaInAsSb layers

    SciTech Connect (OSTI)

    Janiak, F. Motyka, M.; S?k, G.; Dyksik, M.; Ryczko, K.; Misiewicz, J.; Weih, R.; Hfling, S.; Kamp, M.; Patriarche, G.

    2013-12-14

    Optical properties of molecular beam epitaxially grown type II W shaped GaSb/AlSb/InAs/GaIn(As)Sb/InAs/AlSb/GaSb quantum wells (QWs) designed for the active region of interband cascade lasers have been investigated. Temperature dependence of Fourier-transformed photoluminescence and photoreflectance was employed to probe the effects of addition of arsenic into the original ternary valence band well of GaInSb. It is revealed that adding arsenic provides an additional degree of freedom in terms of band alignment and strain tailoring and allows enhancing the oscillator strength of the active type II transition. On the other hand, however, arsenic incorporation apparently also affects the structural and optical material quality via generating carrier trapping states at the interfaces, which can deteriorate the radiative efficiency. These have been evidenced in several spectroscopic features and are also confirmed by cross-sectional transmission electron microscopy images. While arsenic incorporation into type II QWs is a powerful heterostructure engineering tool for optoelectronic devices, a compromise has to be found between ideal band structure properties and high quality morphological properties.

  4. Structural properties of Sb2S3 under pressure: Evidence of an electronic topological transition

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Efthimiopoulos, Ilias; Buchan, Cienna; Wang, Yuejian

    2016-04-06

    High-pressure Raman spectroscopy and x-ray diffraction of Sb2S3 up to 53 GPa reveals two phase transitions at 5 GPa and 15 GPa. The first transition is evidenced by noticeable compressibility changes in distinct Raman-active modes, in the lattice parameter axial ratios, the unit cell volume, as well as in specific interatomic bond lengths and bond angles. By taking into account relevant results from the literature, we assign these effects to a second-order isostructural transition arising from an electronic topological transition in Sb2S3 near 5 GPa. Close comparison between Sb2S3 and Sb2S3 up to 10 GPa reveals a slightly diverse structuralmore » behavior for these two compounds after the isostructural transition pressure. This structural diversity appears to account for the different pressure-induced electronic behavior of Sb2S3 and Sb2S3 up to 10 GPa, i.e. the absence of an insulator-metal transition in Sb2S3 up to that pressure. Lastly, the second high-pressure modification appearing above 15 GPa appears to trigger a structural disorder at ~20 GPa; full decompression from 53 GPa leads to the recovery of an amorphous state.« less

  5. Electrochemical studies of CNT/Si–SnSb nanoparticles for lithium ion batteries

    SciTech Connect (OSTI)

    Nithyadharseni, P.; Reddy, M.V.; Nalini, B.; Ravindran, T.R.; Pillai, B.C.; Kalpana, M.; Chowdari, B.V.R.

    2015-10-15

    Highlights: • Si added SnSb and CNT exhibits very low particle size of below 30 nm • A strong PL quenching due to the addition of Si to SnSb. • Electrochemical studies show CNT added SnSb shows good capacity retention. - Abstract: Nano-structured SnSb, SnSb–CNT, Si–SnSb and Si–SnSb–CNT alloys were synthesized from metal chlorides of Sn, Sb and Si via reductive co-precipitation technique using NaBH{sub 4} as reducing agent. The as prepared compounds were characterized by various techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), Raman, Fourier transform infra-red (FTIR) and photoluminescence (PL) spectroscopy. The electrochemical performances of the compounds were characterized by galvanostatic cycling (GC) and cyclic voltammetry (CV). The Si–SnSb–CNT compound shows a high reversible capacity of 1200 mAh g{sup −1}. However, the rapid capacity fading was observed during cycling. In contrast, SnSb–CNT compound showed a high reversible capacity of 568 mAh g{sup −1} at 30th cycles with good cycling stability. The improved reversible capacity and cyclic performance of the SnSb–CNT compound could be attributed to the nanosacle dimension of SnSb particles and the structural advantage of CNTs.

  6. Pressure dependence of donor excitation spectra in AlSb

    SciTech Connect (OSTI)

    Hsu, L.; McCluskey, M.D.; Haller, E.E.

    2002-01-16

    We have investigated the behavior of ground to bound excited-state electronic transitions of Se and Te donors in AlSb as a function of hydrostatic pressure. Using broadband far-infrared Fourier transform spectroscopy, we observe qualitatively different behaviors of the electronic transition energies of the two donors. While the pressure derivative of the Te transition energy is small and constant, as might be expected for a shallow donor, the pressure derivatives of the Se transition energies are quadratic and large at low pressures, indicating that Se is actually a deep donor. In addition, at pressures between 30 and 50 kbar, we observe evidence of an anti-crossing between one of the selenium electronic transitions and a two-phonon mode.

  7. Isotopic Analysis At Mt St Helens Area (Shevenell & Goff, 2000...

    Open Energy Info (EERE)

    Home Exploration Activity: Isotopic Analysis At Mt St Helens Area (Shevenell & Goff, 2000) Exploration Activity Details Location Mt St Helens Area Exploration Technique...

  8. Compound and Elemental Analysis At Mt St Helens Area (Shevenell...

    Open Energy Info (EERE)

    Exploration Activity: Compound and Elemental Analysis At Mt St Helens Area (Shevenell & Goff, 2000) Exploration Activity Details Location Mt St Helens Area Exploration Technique...

  9. Geothermometry At Mt St Helens Area (Shevenell & Goff, 1995)...

    Open Energy Info (EERE)

    St Helens Area (Shevenell & Goff, 1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermometry At Mt St Helens Area (Shevenell & Goff,...

  10. Isotopic Analysis At Mt St Helens Area (Shevenell & Goff, 1995...

    Open Energy Info (EERE)

    Home Exploration Activity: Isotopic Analysis At Mt St Helens Area (Shevenell & Goff, 1995) Exploration Activity Details Location Mt St Helens Area Exploration Technique...

  11. Compound and Elemental Analysis At Mt St Helens Area (Shevenell...

    Open Energy Info (EERE)

    Exploration Activity: Compound and Elemental Analysis At Mt St Helens Area (Shevenell & Goff, 1995) Exploration Activity Details Location Mt St Helens Area Exploration Technique...

  12. Hawaii's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Hawaii. Registered Networking Organizations in Hawaii's 1st congressional district Hawaii Public Utilities Commission Registered Energy Companies in Hawaii's 1st congressional...

  13. East Grand St Bridge Snowmelt Low Temperature Geothermal Facility...

    Open Energy Info (EERE)

    East Grand St Bridge Snowmelt Low Temperature Geothermal Facility Jump to: navigation, search Name East Grand St Bridge Snowmelt Low Temperature Geothermal Facility Facility East...

  14. Arkansas's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Act Smart Grid Projects in Arkansas's 1st congressional district Woodruff Electric Smart Grid Project Utility Companies in Arkansas's 1st congressional district City Water...

  15. Michigan's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Registered Energy Companies in Michigan's 1st congressional district AG Solutions Inc Dow Chemical Co Dow Kokam Energy Generation Facilities in Michigan's 1st congressional...

  16. Washington University in St Louis | Open Energy Information

    Open Energy Info (EERE)

    in St Louis Jump to: navigation, search Name: Washington University in St Louis Place: Missouri Product: University with large research departments, particularly medical....

  17. St. Mary's Hospital Space Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Hospital Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name St. Mary's Hospital Space Heating Low Temperature Geothermal Facility Facility St....

  18. Virginia's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Virginia's 1st congressional district Delta T Corporation E85 Inc Virginia Biodiesel Refinery Utility Companies in Virginia's 1st congressional district Rappahannock Electric Coop...

  19. 21st century Green Solutions LLC | Open Energy Information

    Open Energy Info (EERE)

    21st century Green Solutions LLC Jump to: navigation, search Name: 21st century Green Solutions, LLC Place: Grand Blanc, Michigan Zip: 48439 Sector: Wind energy Product: Exclusive...

  20. St. James Parish, Louisiana: Energy Resources | Open Energy Informatio...

    Open Energy Info (EERE)

    Energy Generation Facilities in St. James Parish, Louisiana IMC Phosphates Company Uncle Sam Biomass Facility Places in St. James Parish, Louisiana Gramercy, Louisiana Lutcher,...

  1. St. Charles Parish, Louisiana: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Louisiana Montz, Louisiana New Sarpy, Louisiana Norco, Louisiana Paradis, Louisiana St. Rose, Louisiana Taft, Louisiana Retrieved from "http:en.openei.orgwindex.php?titleSt.C...

  2. Boise Inc. St. Helens Paper Mill Achieves Significant Fuel Savings...

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

    Boise Inc. St. Helens Paper Mill Achieves Significant Fuel Savings Boise Inc. St. Helens Paper Mill Achieves Significant Fuel Savings This case study describes how the Boise Inc. ...

  3. St. Clair County, Illinois: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    in St. Clair County, Illinois DarkStar VI Mid America Advanced Power Solutions Midwest Biodiesel Products Energy Generation Facilities in St. Clair County, Illinois Milam Gas...

  4. Using SDI-12 with ST microelectronics MCU's

    SciTech Connect (OSTI)

    Saari, Alexandra; Hinzey, Shawn Adrian; Frigo, Janette Rose; Proicou, Michael Chris; Borges, Louis

    2015-09-03

    ST Microelectronics microcontrollers and processors are readily available, capable and economical processors. Unfortunately they lack a broad user base like similar offerings from Texas Instrument, Atmel, or Microchip. All of these devices could be useful in economical devices for remote sensing applications used with environmental sensing. With the increased need for environmental studies, and limited budgets, flexibility in hardware is very important. To that end, and in an effort to increase open support of ST devices, I am sharing my teams' experience in interfacing a common environmental sensor communication protocol (SDI-12) with ST devices.

  5. In-situ TEM study of sodiation and failure mechanism of Sb anodes...

    Office of Scientific and Technical Information (OSTI)

    Title: In-situ TEM study of sodiation and failure mechanism of Sb anodes. Abstract not provided. Authors: XueHai Tan ; Jungjohann, Katherine Leigh ; Mook, William ; David Mitlin ...

  6. Intense terahertz emission from molecular beam epitaxy-grown GaAs/GaSb(001)

    SciTech Connect (OSTI)

    Sadia, Cyril P.; Laganapan, Aleena Maria; Agatha Tumanguil, Mae; Estacio, Elmer; Somintac, Armando; Salvador, Arnel; Que, Christopher T.; Yamamoto, Kohji; Tani, Masahiko

    2012-12-15

    Intense terahertz (THz) electromagnetic wave emission was observed in undoped GaAs thin films deposited on (100) n-GaSb substrates via molecular beam epitaxy. GaAs/n-GaSb heterostructures were found to be viable THz sources having signal amplitude 75% that of bulk p-InAs. The GaAs films were grown by interruption method during the growth initiation and using various metamorphic buffer layers. Reciprocal space maps revealed that the GaAs epilayers are tensile relaxed. Defects at the i-GaAs/n-GaSb interface were confirmed by scanning electron microscope images. Band calculations were performed to infer the depletion region and electric field at the i-GaAs/n-GaSb and the air-GaAs interfaces. However, the resulting band calculations were found to be insufficient to explain the THz emission. The enhanced THz emission is currently attributed to a piezoelectric field induced by incoherent strain and defects.

  7. A new n-type half-Heusler thermoelectric material NbCoSb (Journal...

    Office of Scientific and Technical Information (OSTI)

    new n-type half-Heusler thermoelectric material NbCoSb Citation Details In-Document Search This content will become publicly available on June 15, 2017 Title: A new n-type ...

  8. A new n-type half-Heusler thermoelectric material NbCoSb (Journal...

    Office of Scientific and Technical Information (OSTI)

    A new n-type half-Heusler thermoelectric material NbCoSb This content will become publicly available on June 15, 2017 Prev Next Title: A new n-type half-Heusler ...

  9. Ultrafast Terahertz-Induced Response of GeSbTe Phase-Change Materials...

    Office of Scientific and Technical Information (OSTI)

    Title: Ultrafast Terahertz-Induced Response of GeSbTe Phase-Change Materials ... Resource Relation: Journal Name: Appl. Phys. Lett.; Journal Volume: 104; Journal Issue: 25 Research ...

  10. Material and device characteristics of InAs/GaAsSb sub-monolayer quantum dot solar cells

    SciTech Connect (OSTI)

    Kim, Yeongho; Ban, Keun-Yong Zhang, Chaomin; Honsberg, Christiana B.

    2015-10-12

    We have studied the material and photovoltaic characteristics of InAs/GaAsSb sub-monolayer quantum dot solar cells (QDSCs) with different Sb contents of 0%, 5%, 15%, and 20%. All QDSCs exhibit an extended external quantum efficiency (EQE) response in the wavelength range of 960–1000 nm that corresponds to sub-bandgap photon absorption. As Sb content increases from 5% to 20%, the cutoff wavelength in the EQE extends towards longer wavelength whilst the EQE in the wavelength region of 300–880 nm is lowered due to increased defect density. Compared to the QDSC (Sb 0%), an Sb incorporation of 5% enhances the short-circuit current density from 20.65 to 22.15 mA/cm{sup 2} induced by Sb surfactant effect. Since the open-circuit voltage and fill factor of the QDSC (Sb 5%) are comparable to those of the QDSC (Sb 0%), an enhancement in solar cell efficiency (10.5%) of the QDSC (Sb 5%) is observed. Further increasing Sb content to 15% and 20% results in the degradation of solar cell performance due to increased nonradiative recombination and large valence band offset in a type-II band line-up.

  11. Structure and magnetic properties of LnMnSbO ( Ln=La and Ce)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Qiang; Kumar, C. M. N.; Tian, Wei; Dennis, Kevin W.; Goldman, Alan I.; Vaknin, David

    2016-03-11

    Here, a neutron powder diffraction (NPD) study of LnMnSbO (Ln = La or Ce) reveals differences between the magnetic ground state of the two compounds due to the strong Ce-Mn coupling compared to La-Mn. The two compounds adopt the P4/nmm space group down to 2 K, and whereas magnetization measurements do not show obvious anomaly at high temperatures, NPD reveals a C-type antiferromagnetic (AFM) order below TN = 255K for LaMnSbO and 240 K for CeMnSbO. While the magnetic structure of LaMnSbO is preserved to base temperature, a sharp transition at TSR = 4.5K is observed in CeMnSbO due tomore » a spin-reorientation (SR) transition of the Mn2+ magnetic moments from pointing along the c axis to the ab plane. The SR transition in CeMnSbO is accompanied by a simultaneous long-range AFM ordering of the Ce moments, which indicates that the Mn SR transition is driven by the Ce-Mn coupling. The ordered moments are found to be somewhat smaller than those expected for Mn2+ (S = 5/2) in insulators, but large enough to suggest that these compounds belong to the class of local-moment antiferromagnets. The lower TN found in these two compounds compared to the As-based counterparts (TN = 317 for LaMnAsO, TN = 347K for CeMnAsO) indicates that the Mn-Pn (Pn=As or Sb) hybridization that mediates the superexchange Mn-Pn-Mn coupling is weaker for the Sb-based compounds.« less

  12. Ultrafast Terahertz-Induced Response of GeSbTe Phase-Change Materials

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Journal Article: Ultrafast Terahertz-Induced Response of GeSbTe Phase-Change Materials Citation Details In-Document Search Title: Ultrafast Terahertz-Induced Response of GeSbTe Phase-Change Materials Authors: Shu, Michael J. ; Zalden, Peter ; Chen, Frank ; Weems, Ben ; Chatzakis, Ioannis ; Xiong, Feng ; Jeyasingh, Rakesh ; Hoffmann, Matthias C. ; Pop, Eric ; Wong, H.-S.Philip ; Wuttig, Matthias ; Lindenberg, Aaron M. Publication Date: 2014-07-08 OSTI

  13. AlSb/InAs HIGH ELECTRON MOBILITY TRANSISTORS - Energy Innovation Portal

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

    Electricity Transmission Electricity Transmission Advanced Materials Advanced Materials Find More Like This Return to Search AlSb/InAs HIGH ELECTRON MOBILITY TRANSISTORS Naval Research Laboratory Contact NRL About This Technology Technology Marketing Summary The Naval Research Laboratory (NRL) has developed materials growth and fabrication technology for the manufacture of high-speed, low power AlSb/InAs high electron mobility transistors (HEMTs) that exhibit state-of-the-art low-power

  14. SL/ST Performance Management Training

    Broader source: Energy.gov [DOE]

    The training provides an overview of DOE's SL/ST appraisal system, as well as describes key actions within all of the major phases of the annual performance management cycle. The guidance/training...

  15. Electrical properties of n-type GaSb substrates and p-type GaSb buffer layers for InAs/InGaSb superlattice infrared detectors

    SciTech Connect (OSTI)

    Mitchel, W. C. Haugan, H. J.; Mou, Shin; Brown, G. J.; Elhamri, S.; Berney, R.

    2015-09-15

    Lightly doped n-type GaSb substrates with p-type GaSb buffer layers are the preferred templates for growth of InAs/InGaSb superlattices used in infrared detector applications because of relatively high infrared transmission and a close lattice match to the superlattices. We report here temperature dependent resistivity and Hall effect measurements of bare substrates and substrate-p-type buffer layer structures grown by molecular beam epitaxy. Multicarrier analysis of the resistivity and Hall coefficient data demonstrate that high temperature transport in the substrates is due to conduction in both the high mobility zone center Γ band and the low mobility off-center L band. High overall mobility values indicate the absence of close compensation and that improved infrared and transport properties were achieved by a reduction in intrinsic acceptor concentration. Standard transport measurements of the undoped buffer layers show p-type conduction up to 300 K indicating electrical isolation of the buffer layer from the lightly n-type GaSb substrate. However, the highest temperature data indicate the early stages of the expected p to n type conversion which leads to apparent anomalously high carrier concentrations and lower than expected mobilities. Data at 77 K indicate very high quality buffer layers.

  16. Antiferromagnetic ordering in the doped Kondo insulator CeRhSb

    SciTech Connect (OSTI)

    Menon, L.; Malik, S.K.

    1997-06-01

    CeRhSb, the so-called {open_quotes}Kondo insulator,{close_quotes} is a mixed-valent compound showing a gap formation in the electronic density of states. On the other hand, CePdSb is ferromagnetically ordered with a Curie temperature of {approximately}17 K. We have carried out magnetic susceptibility and electrical resistivity measurements on CeRh{sub 1{minus}x}Pd{sub x}Sb (0{le}x{le}1.0), to study the ground-state properties of this system. For small Pd doping in CeRhSb, up to 20{percent}, the gap continually diminishes and no magnetic ordering is observed down to 2 K. In the region 0.3{le}x{le}0.4, as soon as the gap is suppressed, an antiferromagnetic ground state is observed. In the region 0.5{le}x{lt}0.7, the compounds are not single phase. At the CePdSb end, in the region 0.7{le}x{le}1, the ground state is ferromagnetic. The observation of an antiferromagnetic phase in the phase diagram of CeRh{sub 1{minus}x}Pd{sub x}Sb, where neither end is antiferromagnetic, is interesting and is discussed in the light of some recent theoretical models. {copyright} {ital 1997} {ital The American Physical Society}

  17. The magnetic structure of EuCu2Sb2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ryan, D. H.; Cadogan, J. M.; Anand, V. K.; Johnston, D. C.; Flacau, R.

    2015-05-06

    Antiferromagnetic ordering of EuCu2Sb2 which forms in the tetragonal CaBe2Ge2-type structure (space group P4/nmm #129) has been studied using neutron powder diffraction and 151Eu Mössbauer spectroscopy. The room temperature 151Eu isomer shift of –12.8(1) mm/s shows the Eu to be divalent, while the 151Eu hyperfine magnetic field (Bhf) reaches 28.7(2) T at 2.1 K, indicating a full Eu2+ magnetic moment. Bhf(T) follows a smoothmore » $$S=\\frac{7}{2}$$ Brillouin function and yields an ordering temperature of 5.1(1) K. Refinement of the neutron diffraction data reveals a collinear A-type antiferromagnetic arrangement with the Eu moments perpendicular to the tetragonal c-axis. As a result, the refined Eu magnetic moment at 0.4 K is 7.08(15) μB which is the full free-ion moment expected for the Eu2+ ion with $$S=\\frac{7}{2}$$ and a spectroscopic splitting factor of g = 2.« less

  18. Interconnection of thermal parameters, microstructure and mechanical properties in directionally solidified Sn–Sb lead-free solder alloys

    SciTech Connect (OSTI)

    Dias, Marcelino; Costa, Thiago; Rocha, Otávio; Spinelli, José E.; Cheung, Noé; Garcia, Amauri

    2015-08-15

    Considerable effort is being made to develop lead-free solders for assembling in environmental-conscious electronics, due to the inherent toxicity of Pb. The search for substitute alloys of Pb–Sn solders has increased in order to comply with different soldering purposes. The solder must not only meet the expected levels of electrical performance but may also have appropriate mechanical strength, with the absence of cracks in the solder joints. The Sn–Sb alloy system has a range of compositions that can be potentially included in the class of high temperature solders. This study aims to establish interrelations of solidification thermal parameters, microstructure and mechanical properties of Sn–Sb alloys (2 wt.%Sb and 5.5 wt.%Sb) samples, which were directionally solidified under cooling rates similar to those of reflow procedures in industrial practice. A complete high-cooling rate cellular growth is shown to be associated with the Sn–2.0 wt.%Sb alloy and a reverse dendrite-to-cell transition is observed for the Sn–5.5 wt.%Sb alloy. Strength and ductility of the Sn–2.0 wt.%Sb alloy are shown not to be affected by the cellular spacing. On the other hand, a considerable variation in these properties is associated with the cellular region of the Sn–5.5 wt.%Sb alloy casting. - Graphical abstract: Display Omitted - Highlights: • The microstructure of the Sn–2 wt.%Sb alloy is characterized by high-cooling rates cells. • Reverse dendrite > cell transition occurs for Sn–5.5 wt.%Sb alloy: cells prevail for cooling rates > 1.2 K/s. • Sn–5.5 wt.%Sb alloy: the dendritic region occurs for cooling rates < 0.9 K/s. • Sn–5.5 wt.%Sb alloy: tensile properties are improved with decreasing cellular spacing.

  19. Solvothermal synthesis of graphene-Sb{sub 2}S{sub 3} composite and the degradation activity under visible light

    SciTech Connect (OSTI)

    Tao, Wenguang; Chang, Jiuli; Wu, Dapeng; Gao, Zhiyong; Duan, Xiaoli; Xu, Fang; Engineering Technology Research Center of Motive Power and Key Materials, Henan, 453007 ; Jiang, Kai; Engineering Technology Research Center of Motive Power and Key Materials, Henan, 453007

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ? Graphene-Sb{sub 2}S{sub 3} composites were synthesized through a facile solvothermal method. ? Hydroxyl radicals are the main species responsible for the photodegradation activity. ? Graphene-Sb{sub 2}S{sub 3} demonstrated dramatically improved visible light degradation activity. -- Abstract: Novel graphene-Sb{sub 2}S{sub 3} (G-Sb{sub 2}S{sub 3}) composites were synthesized via a facile solvothermal method with graphene oxide (GO), SbCl{sub 3} and thiourea as the reactants. GO played an important role in controlling the size and the distribution of the formed Sb{sub 2}S{sub 3} nanoparticles on the graphene sheets with different density. Due to the negative surface charge, smaller Sb{sub 2}S{sub 3} particles size and efficient electrons transfer from Sb{sub 2}S{sub 3} to graphene, the composites demonstrated improved photodegradation activity on rhodamine B (RhB). Among these composites, the product G-Sb{sub 2}S{sub 3} 0.1, which was synthesized with the GO concentration of 0.1 mg/mL, exhibited the highest photodegradation activity owing to the considerable density of Sb{sub 2}S{sub 3} nanoparticles onto graphene sheet free of aggregation. Hydroxyl radicals (OH) derived from conduction band (CB) electrons of Sb{sub 2}S{sub 3} is suggested to be responsible for the photodegradation of RhB. The high visible light degradation activity and the satisfactory cycling stability made the as-prepared G-Sb{sub 2}S{sub 3} 0.1 an applicable photocatalyst.

  20. Superconductivity in strong spin orbital coupling compound Sb2Se3

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kong, P. P.; Sun, F.; Xing, L. Y.; Zhu, J.; Zhang, S. J.; Li, W. M.; Liu, Q. Q.; Wang, X. C.; Feng, S. M.; Yu, X. H.; et al

    2014-10-20

    Recently, A2B3 type strong spin orbital coupling compounds such as Bi2Te3, Bi2Se3 and Sb2Te3 were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb2Se3 on the other hand was found to be topological trivial, but theoretical studies indicated that the pressure might induce Sb2Se3 into a topological nontrivial state. We report on the discovery of superconductivity in Sb2Se3 single crystal induced via pressure. Our experiments indicated that Sb2Se3 became superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition at ~3 GPa which should be related tomore » the topological quantum transition. The superconducting transition temperature (TC) increased to around 8.0 K with pressure up to 40 GPa while it keeps ambient structure. As a result, high pressure Raman revealed that new modes appeared around 10 GPa and 20 GPa, respectively, which correspond to occurrence of superconductivity and to the change of TC slop as the function of high pressure in conjunction with the evolutions of structural parameters at high pressures.« less

  1. Sb{sub 2}O{sub 4} at high pressures and high temperatures

    SciTech Connect (OSTI)

    Orosel, D.; Balog, P.; Liu, H.; Qian, J.; Jansen, M. . E-mail: m.jansen@fkf.mpg.de

    2005-09-15

    Investigations on Sb{sub 2}O{sub 4} at high pressure and temperature have been performed up to 600{sup o}C and up to 27.3GPa. The so-called 'high temperature' phase ({beta}-Sb{sub 2}O{sub 4}) was obtained following pressure increase at ambient temperature and at relatively low temperatures. Thus, in contrast to previous perceptions, {beta}-Sb{sub 2}O{sub 4} is the modification more stable at high pressures, i.e., at low temperatures. The fact that the metastable {alpha}-form is typically obtained through the conventional way of preparation has to be attributed to kinetic effects. The pressure-induced phase transitions have been monitored by in-situ X-ray diffraction in a diamond anvil cell, and confirmed ex-situ, by X-ray diffraction at ambient conditions, following temperature decrease and decompression in large volume devices. Bulk modulus values have been derived from the pressure-induced volume changes at room temperature, and are 143GPa for {alpha}-Sb{sub 2}O{sub 4} and 105GPa for the {beta}-Sb{sub 2}O{sub 4}.

  2. Performance Study of K2CsSb Photocathode Inside a DC High Voltage Gun

    SciTech Connect (OSTI)

    McCarter J. L.; Rao T.; Smedley, J.; Grames, J.; Mammei, R.; Poelker, M.; Suleiman, R.

    2011-09-01

    In the past decade, there has been considerable interest in the generation of tens of mA average current in a photoinjector. Until recently, GaAs:Cs cathodes and K{sub 2}CsSb cathodes have been tested successfully in DC and RF injectors respectively for this application. Our goal is to test the K{sub 2}CsSb photocathode inside a DC gun. Since the multialkali cathode is a compound with constant characteristics over its entire thickness, we anticipate that the lifetime issues seen in GaAs:Cs due to surface damage by ion bombardment would be minimized. Hence successful operation of the K{sub 2}CsSb cathode in a DC gun could lead to a relatively robust electron source capable of delivering ampere level currents. In order to test the performance of a K{sub 2}CsSb cathode in a DC gun, we have designed and built a load lock system that allows the fabrication of the cathode at Brookhaven National Lab (BNL) and its testing at Jefferson Lab (JLab). In this paper, we will present the performance of the K{sub 2}CsSb photocathode in the preparation chamber and in the DC gun.

  3. Lattice-registered growth of GaSb on Si (211) with molecular beam epitaxy

    SciTech Connect (OSTI)

    Hosseini Vajargah, S.; Botton, G. A.; Ghanad-Tavakoli, S.; Preston, J. S.; Kleiman, R. N.

    2012-11-01

    A GaSb film was grown on a Si(211) substrate using molecular beam epitaxy indicating full lattice relaxation as well as full lattice registration and dislocation-free growth in the plane perpendicular to the [01 - 1]-direction. Heteroepitaxy of GaSb on a Si(211) substrate is dominated by numerous first order and multiple higher order micro-twins. The atomic-resolved structural study of GaSb films by high-angle annular dark-field scanning transmission electron microscopy reveals that slight tilt, along with twinning, favors the lattice registry to Si(211) substrates. Preferential bonding of impinging Ga and Sb atoms at the interface due to two distinctive bonding sites on the Si(211) surface enables growth that is sublattice-ordered and free of anti-phase boundaries. The role of the substrate orientation on the strain distribution of GaSb epilayers is further elucidated by investigating the local change in the lattice parameter using the geometric phase analysis method and hence effectiveness of the lattice tilting in reducing the interfacial strain was confirmed further.

  4. Fragile structural transition in Mo3Sb7

    SciTech Connect (OSTI)

    Yan, Jiaqiang -Q.; McGuire, Michael A; May, Andrew F; Parker, David S.; Mandrus, D. G.; Sales, Brian C.

    2015-08-10

    Mo3Sb7 single crystals lightly doped with Cr, Ru, or Te are studied in order to explore the interplay between superconductivity, magnetism, and the cubic-tetragonal structural transition. The structural transition at 53 K is extremely sensitive to Ru or Te substitution which introduces additional electrons, but robust against Cr substitution. We observed no sign of a structural transition in superconducting Mo2.91Ru0.09Sb7 and Mo3Sb6.975Te0.025. In contrast, 3 at.% Cr doping only slightly suppresses the structural transition to 48 K while leaving no trace of superconductivity above 1.8 K. Analysis of magnetic properties suggests that the interdimer interaction in Mo3Sb7 is near a critical value and essential for the structural transition. Futhermore, all dopants suppress the superconductivity of Mo3Sb7. The tetragonal structure is not necessary for superconductivity.

  5. Semiconductor structures having electrically insulating and conducting portions formed from an AlSb-alloy layer

    DOE Patents [OSTI]

    Spahn, O.B.; Lear, K.L.

    1998-03-10

    The semiconductor structure comprises a plurality of semiconductor layers formed on a substrate including at least one layer of a III-V compound semiconductor alloy comprising aluminum (Al) and antimony (Sb), with at least a part of the AlSb-alloy layer being chemically converted by an oxidation process to form superposed electrically insulating and electrically conducting portions. The electrically insulating portion formed from the AlSb-alloy layer comprises an oxide of aluminum (e.g., Al{sub 2}O{sub 3}), while the electrically conducting portion comprises Sb. A lateral oxidation process allows formation of the superposed insulating and conducting portions below monocrystalline semiconductor layers for forming many different types of semiconductor structures having particular utility for optoelectronic devices such as light-emitting diodes, edge-emitting lasers, vertical-cavity surface-emitting lasers, photodetectors and optical modulators (waveguide and surface normal), and for electronic devices such as heterojunction bipolar transistors, field-effect transistors and quantum-effect devices. The invention is expected to be particularly useful for forming light-emitting devices for use in the 1.3--1.6 {mu}m wavelength range, with the AlSb-alloy layer acting to define an active region of the device and to effectively channel an electrical current therein for efficient light generation. 10 figs.

  6. Semiconductor structures having electrically insulating and conducting portions formed from an AlSb-alloy layer

    DOE Patents [OSTI]

    Spahn, Olga B.; Lear, Kevin L.

    1998-01-01

    A semiconductor structure. The semiconductor structure comprises a plurality of semiconductor layers formed on a substrate including at least one layer of a III-V compound semiconductor alloy comprising aluminum (Al) and antimony (Sb), with at least a part of the AlSb-alloy layer being chemically converted by an oxidation process to form superposed electrically insulating and electrically conducting portions. The electrically insulating portion formed from the AlSb-alloy layer comprises an oxide of aluminum (e.g. Al.sub.2 O.sub.3), while the electrically conducting portion comprises Sb. A lateral oxidation process allows formation of the superposed insulating and conducting portions below monocrystalline semiconductor layers for forming many different types of semiconductor structures having particular utility for optoelectronic devices such as light-emitting diodes, edge-emitting lasers, vertical-cavity surface-emitting lasers, photodetectors and optical modulators (waveguide and surface normal), and for electronic devices such as heterojunction bipolar transistors, field-effect transistors and quantum-effect devices. The invention is expected to be particularly useful for forming light-emitting devices for use in the 1.3-1.6 .mu.m wavelength range, with the AlSb-alloy layer acting to define an active region of the device and to effectively channel an electrical current therein for efficient light generation.

  7. 21st International Conference on Photochemical Conversion and Storage of

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

    Solar Energy "IPS-21" (St. Petersburg, Russia) - JCAP 1st International Conference on Photochemical Conversion and Storage of Solar Energy "IPS-21" (St. Petersburg, Russia) 21st International Conference on Photochemical Conversion and Storage of Solar Energy "IPS-21" (St. Petersburg, Russia) Mon, Jul 25, 2016 3:30pm 15:30 Fri, Jul 29, 2016 4:30pm 16:30 St. Petersburg Russia Joel Haber, "Artificial Photosynthesis-Progress and Prospects" July 24 2016

  8. Natural nanostructure and superlattice nanodomains in AgSbTe{sub 2}

    SciTech Connect (OSTI)

    Carlton, Christopher E.; De Armas, Ricardo; Shao-Horn, Yang E-mail: shaohorn@mit.edu; Ma, Jie; May, Andrew F.; Delaire, Olivier E-mail: shaohorn@mit.edu

    2014-04-14

    AgSbTe{sub 2} has long been of interest for thermoelectric applications because of its favorable electronic properties and its low lattice thermal conductivity of ?0.7?W/mK. In this work, we report new findings from a high-resolution transmission electron microscopy study revealing two nanostructures in single crystal Ag{sub 1?x}Sb{sub 1+x}Sb{sub 2+x} (with x?=?0, 0.1, 0.2); (i) a rippled natural nanostructure with a period of ?2.55?nm and (ii) superlattice ordered nanodomains consistent with cation ordering predicted in previous density functional theory studies. These nanostructures, combined with point-defects, probably serve as sources of scattering for phonons, thereby yielding a low lattice thermal conductivity over a wide temperature range.

  9. Elastic strains at interfaces in InAs/AlSb multilayer structures for quantum cascade lasers

    SciTech Connect (OSTI)

    Nicolai, J.; Gatel, Ch.; Warot-Fonrose, B.; Ponchet, A.; Teissier, R.; Baranov, A. N.; Magen, C.

    2014-01-20

    InAs/AlSb multilayers similar to those used in quantum cascade lasers have been grown by molecular beam epitaxy on (001) InAs substrates. Elastic strain is investigated by high resolution transmission electron microscopy. Thin interfacial regions with lattice distortions significantly different from the strain of the AlSb layers themselves are revealed from the geometrical phase analysis. Strain profiles are qualitatively compared to the chemical contrast of high angle annular dark field images obtained by scanning transmission electron microscopy. The strain and chemical profiles are correlated with the growth sequences used to form the interfaces. Tensile strained AlAs-like interfaces tend to form predominantly due to the high thermal stability of AlAs. Strongly asymmetric interfaces, AlAs-rich and (Al, In)Sb, respectively, can also be achieved by using appropriate growth sequences.

  10. The Crystallization Behavior of Stochiometric and Off-stochiometric Ga-Sb-Te Materials for Phase-Change Memory

    SciTech Connect (OSTI)

    H Cheng; S Raoux; J Jordan-Sweet

    2011-12-31

    The stoichiometric Ga{sub 4}Sb{sub 6}Te{sub 3} and Ga-Sb materials were systematically studied. The alloy Ga{sub 4}Sb{sub 6}Te{sub 3} shows a fast crystallization speed, very high crystallization temperature, T{sub x}, and high electrical contrast. Although stoichiometric GaSb has similar performance and even faster crystallization speed, the electrical contrast is much lower. The other off-stoichiometric compounds we studied all have higher T{sub x} than Ge{sub 2}Sb{sub 2}Te{sub 5} indicating a good amorphous stability. By raising the Sb/Te ratio with GaSb incorporation, T{sub x} and the recrystallization time of melt-quenched, amorphous samples can be effectively increased. The stoichiometric Ga{sub 4}Sb{sub 6}Te{sub 3} with less likelihood of phase-segregation compared to nonstoichiometric compounds is a promising candidate for phase-change memory.

  11. Evaluation Of Glass Density To Support The Estimation Of Fissile Mass Loadings From Iron Concentrations In SB8 Glasses

    SciTech Connect (OSTI)

    Edwards, T. B.; Peeler, D. K.; Kot, W. K.; Gan, H.; Pegg, I. L.

    2013-04-30

    The Department of Energy Savannah River (DOE-SR) has provided direction to Savannah River Remediation (SRR) to maintain fissile concentration in glass below 897 g/m{sup 3}. In support of that guidance, the Savannah River National Laboratory (SRNL) provided a technical basis and a supporting Microsoft Excel spreadsheet for the evaluation of fissile loading in Sludge Batch 5 (SB5), Sludge Batch 6 (SB6), Sludge Batch 7a (SB7a), and Sludge Batch 7b (SB7b) glass based on the iron (Fe) concentration in glass as determined by the measurements from the Slurry Mix Evaporator (SME) acceptability analysis. SRR has since requested that the necessary density information be provided to allow SRR to update the Excel spreadsheet so that it may be used to maintain fissile concentration in glass below 897 g/m{sup 3} during the processing of Sludge Batch 8 (SB8). One of the primary inputs into the fissile loading spreadsheet includes an upper bound for the density of SB8-based glasses. Thus, these bounding density values are to be used to assess the fissile concentration in this glass system. It should be noted that no changes are needed to the underlying structure of the Excel-based spreadsheet to support fissile assessments for SB8. However, SRR should update the other key inputs to the spreadsheet that are based on fissile and Fe concentrations reported from the SB8 Waste Acceptance Product Specification (WAPS) sample.

  12. St. Croix Chippewa Indians- 2003 Project

    Broader source: Energy.gov [DOE]

    The St. Croix tribe's interest in sustainable economic development has led them to explore using locally available biofuel for power generation. A biofuel power project will leverage community assets and resources and provide a foundation for future sustainable development. It will also help to meet power demands and reduce dependence on imported nonrenewable energy sources.

  13. Nanoscale structure in AgSbTe2 determined by diffuse elastic neutron scattering

    SciTech Connect (OSTI)

    Specht, Eliot D [ORNL; Ma, Jie [ORNL; Delaire, Olivier A [ORNL; Budai, John D [ORNL; May, Andrew F [ORNL; Karapetrova, Evguenia A. [Argonne National Laboratory (ANL)

    2015-01-01

    Diffuse elastic neutron scattering measurements confirm that AgSbTe2 has a hierarchical structure, with defects on length scales from nanometers to microns. While scattering from mesoscale structure is consistent with previously-proposed structures in which Ag and Sb order on a NaCl lattice, more diffuse scattering from nanoscale structure suggests a structural rearrangement in which hexagonal layers form a combination of (ABC), (ABA), and (AAB) stacking sequences. The AgCrSe2 structure is the best-fitting model for the local atomic arrangements.

  14. Low temperature fabrication and doping concentration analysis of Au/Sb ohmic contacts to n-type Si

    SciTech Connect (OSTI)

    Liu, J. Q.; Wang, C.; Zhu, T.; Wu, W. J.; Fan, J.; Tu, L. C.

    2015-11-15

    This paper investigates low temperature ohmic contact formation of Au/Sb to n-type Si substrates through AuSb/NiCr/Au metal stacks. Liquid epitaxy growth is utilized to incorporate Sb dopants into Si substrate in AuSi melt. The best specific contact resistivity achieved is 0.003 Ω ⋅ cm{sup 2} at 425 {sup o}C. Scanning electron microscopy (SEM) reveals inverted pyramidal crater regions at the metal/semiconductor interface, indicating that AuSi alloying efficiently occurs at such sites. Secondary ion mass spectroscopy (SIMS) shows that Sb atoms are successfully incorporated into Si as doping impurities during the anneal process, and the Sb doping concentration at the contact interface is found to be higher than the solid solubility limit in a Si crystal. This ohmic contacts formation method is suitable for semiconductor fabrication processes with limited thermal budget, such as post CMOS integration of MEMS.

  15. Microstructural stability in LPE Ga{sub x}In{sub (1{minus}x)}As{sub y}Sb{sub (1{minus}y)}/GaSb heterostructures

    SciTech Connect (OSTI)

    Chen, C.Y.; Bucklen, V.; Rajan, K.; Freeman, M.; Cardines, R.P.

    1998-06-01

    The morphological and structural characteristics associated with the growth of lattice matched In{sub x}Ga{sub (1{minus}x)}As{sub y}Sb{sub (1{minus}y)}/GaSb (100) heterostructures is presented. The experiments focused on studying the effect of growth on vicinal surfaces tilted from the exact (100) orientation as well as variations in epilayer chemistry. It was found that variations in these process parameters had very strong effects on both the nucleation characteristics of the epilayer and the atomistic scale homogeneity of the alloy. The <100> and <110> variants in compositional modulation/phase separation were detected, as well as the evolution of weak (110) ordering. These results are discussed in the context of other studies on phase stability in III-V epitaxial structures, especially in terms of surface reconstruction and kinetic effects near conditions of spinodal decomposition.

  16. Gate-tunable high mobility remote-doped InSb/In{sub 1−x}Al{sub x}Sb quantum well heterostructures

    SciTech Connect (OSTI)

    Yi, Wei E-mail: MSokolich@hrl.com; Kiselev, Andrey A.; Thorp, Jacob; Noah, Ramsey; Nguyen, Binh-Minh; Bui, Steven; Rajavel, Rajesh D.; Hussain, Tahir; Gyure, Mark F.; Sokolich, Marko E-mail: MSokolich@hrl.com; Kratz, Philip; Qian, Qi; Manfra, Michael J.; Pribiag, Vlad S.; Kouwenhoven, Leo P.; Marcus, Charles M.

    2015-04-06

    Gate-tunable high-mobility InSb/In{sub 1−x}Al{sub x}Sb quantum wells (QWs) grown on GaAs substrates are reported. The QW two-dimensional electron gas (2DEG) channel mobility in excess of 200 000 cm{sup 2}/V s is measured at T = 1.8 K. In asymmetrically remote-doped samples with an HfO{sub 2} gate dielectric formed by atomic layer deposition, parallel conduction is eliminated and complete 2DEG channel depletion is reached with minimal hysteresis in gate bias response of the 2DEG electron density. The integer quantum Hall effect with Landau level filling factor down to 1 is observed. A high-transparency non-alloyed Ohmic contact to the 2DEG with contact resistance below 1 Ω·mm is achieved at 1.8 K.

  17. Properties of Sb{sub 2}S{sub 3} and Sb{sub 2}Se{sub 3} thin films obtained by pulsed laser ablation

    SciTech Connect (OSTI)

    Virt, I. S.; Rudyj, I. O.; Kurilo, I. V.; Lopatynskyi, I. Ye.; Linnik, L. F.; Tetyorkin, V. V.; Potera, P.; Luka, G.

    2013-07-15

    The properties of Sb{sub 2}S{sub 3} and Sb{sub 2}Se{sub 3} thin films of variable thickness deposited onto Al{sub 2}O{sub 3}, Si, and KCl substrates are investigated by the method of pulsed laser ablation. The samples are obtained at a substrate temperature of 180 Degree-Sign C in a vacuum chamber with a residual pressure of 10{sup -5} Torr. The thickness of the films amounted to 40-1500 nm. The structure of the bulk material of the targets and films is investigated by the methods of X-ray diffraction and transmission high-energy electron diffraction, respectively. The electrical properties of the films are investigated in the temperature range of 253-310 K. It is shown that the films have semiconductor properties. The structural features of the films determine their optical parameters.

  18. 1st Quarter 2016 Domestic Uranium Production Report

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

    Table 1. Total production of uranium concentrate in the United States, 1996 - 1st quarter 2016 pounds U 3 O 8 Calendar-year quarter 1st quarter 2nd quarter 3rd quarter 4th quarter ...

  19. FY 2014 SL/ST Performance Appraisal System Guidance

    Broader source: Energy.gov [DOE]

    This document provides a summary of the key performance management requirements for the FY 2014 SL/ST performance management cycle. These requirements should be understood and applied for all SL/ST...

  20. Complex Systems: Science for the 21st Century (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Complex Systems: Science for the 21st Century Citation Details In-Document Search Title: Complex Systems: Science for the 21st Century The workshop was designed ...

  1. Complex Systems: Science for the 21st Century (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Complex Systems: Science for the 21st Century Citation Details In-Document Search Title: Complex Systems: Science for the 21st Century You are accessing a document from the ...

  2. EECBG Success Story: St. Louis Launches Plan for More Sustainable...

    Energy Savers [EERE]

    St. Louis Launches Plan for More Sustainable Community EECBG Success Story: St. Louis Launches Plan for More Sustainable Community March 1, 2013 - 1:56pm Addthis Using money from ...

  3. Sunrayce 97 Continues Day 7 - Smith Center to St. Francis

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

    7 - Smith Center to St. Francis For more information contact: Patrick Booher, Sunrayce Program Manager (202) 586-0713 St. Francis, Kan. -- It was a close race for the top three ...

  4. Frit Development Efforts for Sludge Batch 4 (SB4): Operating Window Assessments fo Scenarios Leading Up to the Selected Preparation Plan for SB4

    SciTech Connect (OSTI)

    Peeler, D

    2006-03-21

    The objective of this report is to document technical information that has been provided to Defense Waste Processing Facility (DWPF) and Closure Business Unit (CBU) personnel as part of the frit development support for Sludge Batch 4 (SB4). The information presented in this report includes projected operating windows (expressed in terms of waste loading) for various sludge blending and/or washing options coupled with candidate frits of interest. Although the Nominal Stage assessment serves as the primary tool for these evaluations, select systems were also evaluated using a Variation Stage assessment in which compositional variations were introduced. In addition, assessments of the impacts of nepheline formation potential and the SO{sub 4}{sup -} solubility limit on the projected operating windows are also provided. Although this information was used as part of the technical basis leading to CBU's development of the preferred SB4 preparation plan, none of the options presented in this report was selected as the preferred plan. Therefore, the information is presented without significant interpretation of the resulting operating windows, but the projected windows are provided so additional insight can be explored if desired. Detailed assessments of the projected operating windows (using both Nominal and Variation Stage assessments) of the preferred sludge preparation plan with candidate frits are to be documented elsewhere. The information provided in this report is focused solely on model-based projections of the operating windows for various SB4 blending strategies of interest. Although nepheline formation potential is monitored via model predictions as a part of this assessment, experimental work investigating the impact of nepheline on glass quality is also being addressed in a parallel study. The results of this paper study and the experimental assessments of melt rate, SO{sub 4} solubility, and/or nepheline formation potential are all critical components of the

  5. PP-99 St. Clair Tunnel Company | Department of Energy

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

    9 St. Clair Tunnel Company PP-99 St. Clair Tunnel Company Presidential Permit authorizong St. Clair Tunnel Company to construct, operate,a nd maintain eelctric transmission facilities at the U.S. - Canada Border PP-99 St. Clair Tunnel Company (1.08 MB) More Documents & Publications PP-48-3 El Paso Eelctric Company PP-90-1 Imperial Irrigation District PP-76 The Vermont Electric Transmission Company

  6. National Electric Transmission Congestion Study - St. Louis Workshop |

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

    Department of Energy St. Louis Workshop National Electric Transmission Congestion Study - St. Louis Workshop On December 8, 2011, DOE hosted a regional pre-study workshop in St. Louis, MO to receive input and suggestions concerning the National Electric Transmission Congestion Study. The workshop flyer, agenda, presentations, and full transcript are available below. National Electric Transmission Congestion Study Eastern Workshops (89.81 KB) 12-08-11 Congestion Workshop Agenda - St Louis

  7. The 21st Century Truck Partnership | Department of Energy

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

    The 21st Century Truck Partnership The 21st Century Truck Partnership 2002 DEER Conference Presentation: 2002_deer_howden.pdf (268.3 KB) More Documents & Publications 21st Century Truck Partnership Roadmap Roadmap and Technical White Papers - 21CTP-0003, December 2006 Roadmap and Technical White Papers for 21st Century Truck Partnership Vehicle Technologies Office Merit Review 2016: Annual Merit Review and Peer Evaluation Meeting

  8. Science in St. Louis | Dr. Tristram R. Kidder | Photosynthetic Antenna

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

    Research Center Tristram R. Kidder Science in St. Louis | Dr. Tristram R. Kidder Ancient Lessons for Modern Times: An Environmental History of the Yellow River, China, 5000-2000 BC November 10, 2015 - 7:00pm Mid-County Branch, St. Louis County Library, 7821 Maryland Ave. St. Louis, MO 63105-3875

  9. The radiation chemistry of Cs-7SB, a solvent modifier used in Cs and Sr extraction

    SciTech Connect (OSTI)

    Mincher, B.J.; Martin, L.R.; Elias, G.; Mezyk, S.P.

    2008-07-01

    The solvent modifier 1-(2,2,3,3-tetrafluoro-propoxy)-3-(4-sec-butylphenoxy)-2-propanol, (Cs- 7SB) is used in conjunction with calixarenes and crown ethers dissolved in alkane diluents for the extraction of Cs and Sr from highly radioactive solutions. Its purpose is to solvate the ligands and the resulting ligand-metal complexes in the organic phase. Given this role, and its relatively high concentration in the formulations used for solvent extraction, radiolytic degradation of Cs-7SB might decrease the extraction efficiency of these elements as the solvent accumulates absorbed radiation dose. This work presents the results of studies of Cs-7SB using post-radiolysis gas chromatography with electron-capture detection and solvent-extraction distribution-ratio measurements. Also presented is the kinetic analysis of the bimolecular rate constant for the modifier's reaction with nitrogen trioxide and nitrogen dioxide radicals, major radiolytically-produced radical species in irradiated aqueous nitric acid. Although Cs-7SB was found to undergo reactions with nitrogen-centered radicals, little decrease in extraction efficiency was found. It is concluded the modifier, always present at concentrations much higher than the ligands, acts as a radical scavenger, protecting ligands from radiolytic attack. (authors)

  10. Performance Study of K2CsSb Photocathode inside a DC High Voltage Gun

    SciTech Connect (OSTI)

    T. Rao, J. Smedley, J.M. Grames, R. Mammei, J.L. McCarter, M. Poelker, R. Suleiman

    2011-03-01

    In the past decade, there has been considerable interest in the generation of tens of mA average current in a photoinjector. Until recently, GaAs:Cs cathodes and K2CsSb cathodes have been tested successfully in DC and RF injectors respectively for this application. Our goal is to test the GaAs:Cs in RF injector and the K2CsSb cathode in the DC gun in order to widen our choices. Since the multialkali cathode is a compound with uniform stochiometry over its entire thickness, we anticipate that the life time issues seen in GaAs:Cs due surface damage by ion bombardment would be minimized with this material. Hence successful operation of the K2CsSb cathode in DC gun could lead to a relatively robust electron source capable of delivering ampere level currents. In order to test the performance of K2CsSb cathode in a DC gun, we have designed and built a load lock system that would allow the fabrication of the cathode at BNL and its testing at JLab. In this paper, we will present the design of the load-lock system, cathode fabrication, and the cathode performance in the preparation chamber and in the DC gun.

  11. Thermoelectric properties of AgSbTe₂ from first-principles calculations

    SciTech Connect (OSTI)

    Rezaei, Nafiseh; Akbarzadeh, Hadi; Hashemifar, S. Javad

    2014-09-14

    The structural, electronic, and transport properties of AgSbTe₂ are studied by using full-relativistic first-principles electronic structure calculation and semiclassical description of transport parameters. The results indicate that, within various exchange-correlation functionals, the cubic Fd3⁻m and trigonal R3⁻m structures of AgSbTe₂ are more stable than two other considered structures. The computed Seebeck coefficients at different values of the band gap and carrier concentration are accurately compared with the available experimental data to speculate a band gap of about 0.1–0.35 eV for AgSbTe₂ compound, in agreement with our calculated electronic structure within the hybrid HSE (Heyd-Scuseria-Ernzerhof) functional. By calculating the semiclassical Seebeck coefficient, electrical conductivity, and electronic part of thermal conductivity, we present the theoretical upper limit of the thermoelectric figure of merit of AgSbTe₂ as a function of temperature and carrier concentration.

  12. Structural phase transition and phonon instabilities in Cu12Sb4S13

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    May, Andrew F.; Delaire, Olivier A.; Niedziela, Jennifer L.; Lara-Curzio, Edgar; Susner, Michael A.; Abernathy, Douglas L.; Kirkham, Melanie J.; McGuire, Michael A.

    2016-02-08

    In this study, a structural phase transition has been discovered in the synthetic tetrahedrite Cu12Sb4S13 at approximately 88 K. Upon cooling, the material transforms from its known cubic symmetry to a tetragonal unit cell that is characterized by an in-plane ordering that leads to a doubling of the unit cell volume. Specific heat capacity measurements demonstrate a hysteresis of more than two degrees in the associated anomaly. A similar hysteresis was observed in powder x-ray diffraction measurements, which also indicate a coexistence of the two phases, and together these results suggest a first-order transition. This structural transition coincides with amore » recently-reported metal-insulator transition, and the structural instability is related to the very low thermal conductivity κ in these materials. Inelastic neutron scattering was used to measure the phonon density of states in Cu12Sb4S13 and Cu10Zn2Sb4S13, both of which possess a localized, low-energy phonon mode associated with strongly anharmonic copper displacements that suppress κ. In Cu12Sb4S13, signatures of the phase transition are observed in the temperature dependence of the localized mode, which disappears at the structural transition. In contrast, in the cubic Zn-doped material, the mode is at slightly higher-energy but observable for all temperatures, though it softens upon cooling.« less

  13. Rashba effect in single-layer antimony telluroiodide SbTeI

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhuang, Houlong L.; Cooper, Valentino R.; Xu, Haixuan; Ganesh, P.; Hennig, Richard G.; Kent, P. R. C.

    2015-09-04

    Exploring spin-orbit coupling (SOC) in single-layer materials is important for potential spintronics applications. In this paper, using first-principles calculations, we show that single-layer antimony telluroiodide SbTeI behaves as a two-dimensional semiconductor exhibiting a G0W0 band gap of 1.82 eV. More importantly, we observe the Rashba spin splitting in the SOC band structure of single-layer SbTeI with a sizable Rashba coupling parameter of 1.39 eV Å, which is significantly larger than that of a number of two-dimensional systems including surfaces and interfaces. The low formation energy and real phonon modes of single-layer SbTeI imply that it is stable. Finally, our studymore » suggests that single-layer SbTeI is a candidate single-layer material for applications in spintronics devices.« less

  14. Structural phase transition and phonon instability in Cu12Sb4S13

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    May, Andrew F.; Delaire, Olivier A.; Niedziela, Jennifer L.; Lara-Curzio, Edgar; Susner, Michael A.; Abernathy, Douglas L.; Kirkham, Melanie J.; McGuire, Michael A.

    2016-02-08

    In this study, a structural phase transition has been discovered in the synthetic tetrahedrite Cu12Sb4S13 at approximately 88 K. Upon cooling, the material transforms from its known cubic symmetry to a tetragonal unit cell that is characterized by an in-plane ordering that leads to a doubling of the unit cell volume. Specific heat capacity measurements demonstrate a hysteresis of more than two degrees in the associated anomaly. A similar hysteresis was observed in powder x-ray diffraction measurements, which also indicate a coexistence of the two phases, and together these results suggest a first-order transition. This structural transition coincides with amore » recently-reported metal-insulator transition, and the structural instability is related to the very low thermal conductivity κ in these materials. Inelastic neutron scattering was used to measure the phonon density of states in Cu12Sb4S13 and Cu10Zn2Sb4S13, both of which possess a localized, low-energy phonon mode associated with strongly anharmonic copper displacements that suppress κ. In Cu12Sb4S13, signatures of the phase transition are observed in the temperature dependence of the localized mode, which disappears at the structural transition. In contrast, in the cubic Zn-doped material, the mode is at slightly higher-energy but observable for all temperatures, though it softens upon cooling.« less

  15. High resolution InSb quantum well ballistic nanosensors for room temperature applications

    SciTech Connect (OSTI)

    Gilbertson, Adam; Cohen, L. F.; Lambert, C. J.; Solin, S. A.

    2013-12-04

    We report the room temperature operation of a quasi-ballistic InSb quantum well Hall sensor that exhibits a high frequency sensitivity of 560nT/?Hz at 20uA bias current. The device utilizes a partitioned buffer layer design that suppresses leakage currents through the mesa floor and can sustain large current densities.

  16. Baseline risk assessment for exposure to contaminants at the St. Louis Site, St. Louis, Missouri

    SciTech Connect (OSTI)

    Not Available

    1993-11-01

    The St. Louis Site comprises three noncontiguous areas in and near St. Louis, Missouri: the St. Louis Downtown Site (SLDS), the St. Louis Airport Storage Site (SLAPS), and the Latty Avenue Properties. The main site of the Latty Avenue Properties includes the Hazelwood Interim Storage Site (HISS) and the Futura Coatings property, which are located at 9200 Latty Avenue. Contamination at the St. Louis Site is the result of uranium processing and disposal activities that took place from the 1940s through the 1970s. Uranium processing took place at the SLDS from 1942 through 1957. From the 1940s through the 1960s, SLAPS was used as a storage area for residues from the manufacturing operations at SLDS. The materials stored at SLAPS were bought by Continental Mining and Milling Company of Chicago, Illinois, in 1966, and moved to the HISS/Futura Coatings property at 9200 Latty Avenue. Vicinity properties became contaminated as a result of transport and movement of the contaminated material among SLDS, SLAPS, and the 9200 Latty Avenue property. This contamination led to the SLAPS, HISS, and Futura Coatings properties being placed on the National Priorities List (NPL) of the US Environmental Protection Agency (EPA). The US Department of Energy (DOE) is responsible for cleanup activities at the St. Louis Site under its Formerly Utilized Sites Remedial Action Program (FUSRAP). The primary goal of FUSRAP is the elimination of potential hazards to human health and the environment at former Manhattan Engineer District/Atomic Energy Commission (MED/AEC) sites so that, to the extent possible, these properties can be released for use without restrictions. To determine and establish cleanup goals for the St. Louis Site, DOE is currently preparing a remedial investigation/feasibility study-environmental impact statement (RI/FS-EIS). This baseline risk assessment (BRA) is a component of the process; it addresses potential risk to human health and the environment associated wi

  17. Solar Policy Environment: Minneapolis/St. Paul

    Broader source: Energy.gov [DOE]

    The cities of Minneapolis and St. Paul joined forces to implement a comprehensive approach to promoting “Solar in the Cities” including commercial and residential solar installations, technical training programs, and city and state policy review. The Cities are marshalling a wide array of expertise through strategic partnerships with Xcel Energy, Minnesota Dept. of Commerce, Minnesota Renewable Energy Society, Green Institute, freEner-g, Int’l Brotherhood of Electrical Workers, League of Minnesota cities, Neighborhood Energy Connection, and Century College.

  18. Advanced ST Plasma Scenario Simulations for NSTX

    SciTech Connect (OSTI)

    C.E. Kessel; E.J. Synakowski; D.A. Gates; R.W. Harvey; S.M. Kaye; T.K. Mau; J. Menard; C.K. Phillips; G. Taylor; R. Wilson; the NSTX Research Team

    2004-10-28

    Integrated scenario simulations are done for NSTX [National Spherical Torus Experiment] that address four primary milestones for developing advanced ST configurations: high {beta} and high {beta}{sub N} inductive discharges to study all aspects of ST physics in the high-beta regime; non-inductively sustained discharges for flattop times greater than the skin time to study the various current-drive techniques; non-inductively sustained discharges at high {beta} for flattop times much greater than a skin time which provides the integrated advanced ST target for NSTX; and non-solenoidal start-up and plasma current ramp-up. The simulations done here use the Tokamak Simulation Code (TSC) and are based on a discharge 109070. TRANSP analysis of the discharge provided the thermal diffusivities for electrons and ions, the neutral-beam (NB) deposition profile, and other characteristics. CURRAY is used to calculate the High Harmonic Fast Wave (HHFW) heating depositions and current drive. GENRAY/CQL3D is used to establish the heating and CD [current drive] deposition profiles for electron Bernstein waves (EBW). Analysis of the ideal-MHD stability is done with JSOLVER, BALMSC, and PEST2. The simulations indicate that the integrated advanced ST plasma is reachable, obtaining stable plasmas with {beta} {approx} 40% at {beta}{sub N}'s of 7.7-9, I{sub P} = 1.0 MA, and B{sub T} = 0.35 T. The plasma is 100% non-inductive and has a flattop of 4 skin times. The resulting global energy confinement corresponds to a multiplier of H{sub 98(y,2)} = 1.5. The simulations have demonstrated the importance of HHFW heating and CD, EBW off-axis CD, strong plasma shaping, density control, and early heating/H-mode transition for producing and optimizing these plasma configurations.

  19. TANK 40 FINAL SB5 CHEMICAL CHARACTERIZATION RESULTS PRIOR TO NP ADDITION

    SciTech Connect (OSTI)

    Bannochie, C.; Click, D.

    2010-01-06

    A sample of Sludge Batch 5 (SB5) was pulled from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). This sample was also analyzed for chemical composition including noble metals. Prior to radionuclide inventory analyses, a final sample of the H-canyon Np stream will be added to bound the Np addition anticipated for Tank 40. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to DWPF as SB5. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB5 sample was transferred from the shipping container into a 4-L high density polyethylene vessel and solids allowed to settle overnight. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 239 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon{reg_sign} vessels and four in Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Due to the use of Zr crucibles and Na in the peroxide fusions, Na and Zr cannot be determined from this preparation. Additionally, other alkali metals, such as Li and K that may be contaminants in the Na{sub 2}O{sub 2} are not determined from this preparation. Three Analytical Reference Glass - 14 (ARG-1) standards were digested along with a blank for each preparation. The ARG-1 glass allows for an assessment of the completeness of each digestion. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma - atomic emission spectroscopy (ICPAES) analysis, inductively coupled plasma - mass spectrometry (ICP-MS) analysis of masses 81-209 and 230

  20. Molecular Beam Epitaxy on Gas Cluster Ion Beam Prepared GaSb Substrates: Towards Improved Surfaces and Interfaces

    SciTech Connect (OSTI)

    Krishnaswami, Kannan; Vangala, Shivashankar R.; Dauplaise, Helen; Allen, Lisa; Dallas, Gordon; Bakken, Daniel; Bliss, David; Goodhue, William

    2008-04-01

    A key problem in producing mid-infrared optoelectronic and low-power electronic devices in the GaSb material system is the lack of substrates with appropriate surfaces for epitaxial growth. Chemical mechanical polishing (CMP) of GaSb results in surface damage accompanied by tenacious oxides that do not easily desorb. To overcome this, we have developed a process using gas cluster ion beams (GCIB) to remove surface damage and produce engineered surface oxides. In this paper, we present surface modification results on GaSb substrates using O2-, CF4/O2-, and HBr-GCIB processes. X-ray photoelectron spectroscopy of GCIB produced surface layers showed the presence of mixed Ga- and Sb-oxides, with mostly Ga-oxides at the interface, desorbing at temperatures ranging 530°C to 560°C. Cross-sectional transmission electron microscopy of molecular beam epitaxy grown GaSb/AlGaSb layers showed that GCIB surfaces yielded smooth defect free substrate to epi transitions as compared to CMP surfaces. Furthermore, HBr-GCIB surfaces exhibited neither dislocation layers nor discernable interfaces, indicating complete oxide desorbtion prior to epigrowth on a clean single crystal template. Atomic force microscopy of GCIB epilayers exhibited smooth surfaces with characteristic step-terrace formations comprising monatomic steps and wide terraces. The HBr-GCIB process can be easily adapted to a large scale manufacturing process for epi-ready GaSb.

  1. Engineering evaluation/cost analysis for decontamination at the St. Louis Downtown Site, St. Louis, Missouri

    SciTech Connect (OSTI)

    Picel, M.H.; Hartmann, H.M.; Nimmagadda, M.R. ); Williams, M.J. )

    1991-05-01

    The US Department of Energy (DOE) is implementing a cleanup program for three groups of properties in the St. Louis, Missouri, area: the St. Louis Downtown Site (SLDS), the St. Louis Airport Site (SLAPS) and vicinity properties, and the Latty Avenue Properties, including the Hazelwood Interim Storage Site (HISS). The general location of these properties is shown in Figure 1; the properties are referred to collectively as the St. Louis Site. None of the properties are owned by DOE, but each property contains radioactive residues from federal uranium processing activities conducted at the SLDS during and after World War 2. The activities addressed in this environmental evaluation/cost analysis (EE/CA) report are being proposed as interim components of a comprehensive cleanup strategy for the St. Louis Site. As part of the Department's Formerly Utilized Sites Remedial Action Program (FUSRAP), DOE is proposing to conduct limited decontamination in support of proprietor-initiated activities at the SLDS, commonly referred to as the Mallinckrodt Chemical Works. The primary goal of FUSRAP activity at the SLDS is to eliminate potential environmental hazards associated with residual contamination resulting from the site's use for government-funded uranium processing activities. 17 refs., 3 figs., 5 tabs.

  2. Direct Evidence for Abrupt Postcrystallization Germanium Precipitation in Thin Phase-Change Films of Sb-15 at. % Ge

    SciTech Connect (OSTI)

    Cabral,C.; Krusin-Elbaum, L.; Bruley, J.; Raoux, S.; Deline, V.; Madan, A.; Pinto, T.

    2008-01-01

    We present evidence for the instability in the crystalline (metallic) state of binary Te-free phase-change Ge-Sb thin films considered for integration into nonvolatile nanosized memory cells. We find that while the amorphous (semiconducting) phase of eutectic Sb-15 at. % Ge is very robust until Sb crystallization at 240 C, at about 350 C, germanium rapidly precipitates out. Ge precipitation, visualized directly with transmission electron microscopy, is exothermic and is found to affect the films' reflectivity, resistance, and stress. It converts melting into a two-step process, which may seriously impact the switching reliability of a device.

  3. Electronically- and crystal-structure-driven magnetic structures and physical properties of RScSb (R = rare earth) compounds. A neutron diffraction, magnetization and heat capacity study

    SciTech Connect (OSTI)

    Ritter, C; Dhar, S K; Kulkarni, R; Provino, A; Paudyal, Durga; Manfrinetti, Pietro; Gschneidner, Karl A

    2014-08-14

    The synthesis of the new equiatomic RScSb ( R = La-Nd, Sm, Gd-Tm, Lu, Y) compounds has been recently reported. These rare earth compounds crystallize in two different crystal structures, adopting the CeScSi-type ( I 4/ mmm) for the lighter R (La-Nd, Sm) and the CeFeSi-type (P4 /nmm) structure for the heavier R ( R = Gd-Tm, Lu, Y). Here we report the results of neutron diffraction, magnetization and heat capacity measurements on some of these compounds ( R = Ce, Pr, Nd, Gd and Tb). Band structure calculations have also been performed on CeScSb and GdScGe (CeScSi-type), and on GdScSb and TbScSb (CeFeSi-type) to compare and understand the exchange interactions in CeScSi and CeFeSi structure types. The neutron diffraction investigation shows that all five compounds order magnetically, with the highest transition temperature of 66 K in TbScSb and the lowest of about 9 K in CeScSb. The magnetic ground state is simple ferromagnetic (τ = [0 0 0]) in CeScSb, as well in NdScSb for 32 >T > 22 K. Below 22 K a second magnetic transition, with propagation vector τ = [¼ ¼ 0], appears in NdScSb. PrScSb has a magnetic structure within, determined by mostly ferromagnetic interactions and antiferromagnetic alignment of the Pr-sites connected through the I-centering ( τ = [1 0 0]). A cycloidal spiral structure with a temperature dependent propagation vector τ = [δ δ ½] is found in TbScSb. The results of magnetization and heat capacity lend support to the main conclusions derived from neutron diffraction. As inferred from a sharp peak in magnetization, GdScSb orders antiferromagnetically at 56 K. First principles calculations show lateral shift of spin split bands towards lower energy from the Fermi level as the CeScSi-type structure changes to the CeFeSi-type structure. This rigid shift may force the system to transform from exchange split ferromagnetic state to the antiferromagnetic state in RScSb compounds (as seen for example in GdScSb and TbScSb) and is proposed to

  4. Temperature-dependent structural property and power factor of n type thermoelectric Bi{sub 0.90}Sb{sub 0.10} and Bi{sub 0.86}Sb{sub 0.14} alloys

    SciTech Connect (OSTI)

    Malik, K.; Das, Diptasikha; Bandyopadhyay, S.; Banerjee, Aritra; Center for Research in Nanoscience and Nanotechnology, University of Calcutta, JD-2, Sector-III, Saltlake City, Kolkata 700 098 ; Mandal, P.; Srihari, Velaga

    2013-12-09

    Thermal variation of structural property, linear thermal expansion coefficient (?), resistivity (?), thermopower (S), and power factor (PF) of polycrystalline Bi{sub 1-x}Sb{sub x} (x?=?0.10 and 0.14) samples are reported. Temperature-dependent powder diffraction experiments indicate that samples do not undergo any structural phase transition. Rietveld refinement technique has been used to perform detailed structural analysis. Temperature dependence of ? is found to be stronger for Bi{sub 0.90}Sb{sub 0.10}. Also, PF for direct band gap Bi{sub 0.90}Sb{sub 0.10} is higher as compared to that for indirect band gap Bi{sub 0.86}Sb{sub 0.14}. Role of electron-electron and electron-phonon scattering on ?, S, and PF has been discussed.

  5. Carrier localization and in-situ annealing effect on quaternary Ga{sub 1-x}In{sub x}As{sub y}Sb{sub 1-y}/GaAs quantum wells grown by Sb pre-deposition

    SciTech Connect (OSTI)

    Thoma, Jiri; Huyet, Guillaume; Tyndall National Institute, UCC, Lee Maltings, Cork ; Liang, Baolai; Huffaker, Diana L.; Lewis, Liam; Hegarty, Stephen P.

    2013-03-18

    Using temperature-dependent photoluminescence spectroscopy, we have investigated and compared intrinsic InGaAs, intrinsic GaInAsSb, and p-i-n junction GaInAsSb quantum wells (QWs) embedded in GaAs barriers. Strong carrier localization inside the intrinsic GaInAsSb/GaAs QW has been observed together with its decrease inside the p-i-n sample. This is attributed to the effect of an in-situ annealing during the top p-doped AlGaAs layer growth at an elevated temperature of 580 Degree-Sign C, leading to Sb-atom diffusion and even atomic redistribution. High-resolution X-ray diffraction measurements and the decrease of both maximum localization energy and full delocalization temperature in the p-i-n QW sample further corroborated this conclusion.

  6. Defect reduction in epitaxial GaSb grown on nanopatterned GaAs substrates using full wafer block copolymer lithography

    SciTech Connect (OSTI)

    Jha, Smita; Liu, C.-C.; Nealey, P. F.; Kuech, T. F.; Kuan, T. S.; Babcock, S. E.; Park, J. H.; Mawst, L. J.

    2009-08-10

    Defect reduction in the large lattice mismatched system of GaSb on GaAs, {approx}7%, was accomplished using full wafer block copolymer (BCP) lithography. A self-assembled BCP mask layer was used to generate a hexagonal pattern of {approx}20 nm holes on {approx}40 nm centers in a 20 nm SiO{sub 2} layer. GaSb growth initially takes place selectively within these holes leading to a dense array of small, strain-relaxed epitaxial GaSb islands. The GaSb grown on the patterned SiO{sub 2} layer exhibits a reduction in the x-ray linewidth attributed to a decrease in the threading dislocation density when compared to blanket pseudomorphic film growth.

  7. Effect of rare-earth doping in RCrSb3 (R = La, Pr, Sm, and Gd...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Effect of rare-earth doping in RCrSb3 (R La, Pr, Sm, and Gd) Citation Details In-Document Search ... We report on the electrical resistivity and magnetic ...

  8. Characterization of silver photodiffusion in Ge{sub 8}Sb{sub 2}Te{sub 11} thin films

    SciTech Connect (OSTI)

    Kumar, Sandeep; Singh, D.; Sandhu, S.; Thangaraj, R.

    2015-06-24

    Silver-doped amorphous Ge{sub 8}Sb{sub 2}Te{sub 11} thin films have been prepared by photodiffusion at room-temperature; the Ge{sub 8}Sb{sub 2}Te{sub 11}/Ag bilayer was deposited by vacuum thermal evaporation. Photodiffusion of Ag into the amorphous Ge{sub 8}Sb{sub 2}Te{sub 11} thin films has been carried out by illuminating the prepared Ge{sub 8}Sb{sub 2}Te{sub 11}/Ag bilayer with halogen lamp. The photodiffused silver depth profile was traced by means of time of flight secondary ion mass spectroscopy. The film remains amorphous after Ag photodiffusion. The crystallization temperature of the films was evaluated by temperature dependent sheet resistance measurement. The amorphous nature and crystalline phases of the films have been identified by using X-ray diffraction.

  9. Impact of stress relaxation in GaAsSb cladding layers on quantum dot creation in InAs/GaAsSb structures grown on GaAs (001)

    SciTech Connect (OSTI)

    Bremner, S. P.; Ban, K.-Y.; Faleev, N. N.; Honsberg, C. B.; Smith, D. J.

    2013-09-14

    We describe InAs quantum dot creation in InAs/GaAsSb barrier structures grown on GaAs (001) wafers by molecular beam epitaxy. The structures consist of 20-nm-thick GaAsSb barrier layers with Sb content of 8%, 13%, 15%, 16%, and 37% enclosing 2 monolayers of self-assembled InAs quantum dots. Transmission electron microscopy and X-ray diffraction results indicate the onset of relaxation of the GaAsSb layers at around 15% Sb content with intersected 60° dislocation semi-loops, and edge segments created within the volume of the epitaxial structures. 38% relaxation of initial elastic stress is seen for 37% Sb content, accompanied by the creation of a dense net of dislocations. The degradation of In surface migration by these dislocation trenches is so severe that quantum dot formation is completely suppressed. The results highlight the importance of understanding defect formation during stress relaxation for quantum dot structures particularly those with larger numbers of InAs quantum-dot layers, such as those proposed for realizing an intermediate band material.

  10. 1994 SSRL 21st USERS MEETING

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

    SSRL 21st USERS MEETING SSRL 12 Oct 1994 October 17-18, 1994, SLAC Auditorium PROGRAM MONDAY, OCTOBER 17 7:30 Registration and Continental Breakfast - Auditorium Breezeway SESSION I Chair: Louis Terminello 8:30 Welcome - L. Terminello (LLNL) 8:35 SSRL Director's Report - A. Bienenstock (SSRL) 9:15 SSRLUO Report - J. Kortright (LBL) 9:30 Report from Washington - W. Oosterhuis (DOE) 9:45 Coffee Break SESSION II Surface and Reduced Dimensional Studies Chair: Charles Fadley lO:15 Ultra-trace Metal

  11. The reaction mechanism of FeSb2 as anode for sodium-ion batteries

    SciTech Connect (OSTI)

    Baggetto, Loic; Hah, Hien-Yoong; Charles E. Johnson; Bridges, Craig A.; Johnson, Jackie A.; Veith, Gabriel M.

    2014-04-04

    The electrochemical reaction of FeSb2 with Na is reported for the first time. The first discharge (sodiation) potential profile of FeSb2 is characterized by a gentle slope centered at 0.25 V. During charge (Na removal) and the subsequent discharge, the main reaction takes place near 0.7 V and 0.4 V, respectively. The reversible storage capacity amounts to 360 mA h g-1, which is smaller than the theoretical value of 537 mA h g-1. The reaction, studied by ex situ and in situ X-ray diffraction, is found to proceed by the consumption of crystalline FeSb2 to form an amorphous phase. Upon further sodiation, the formation of nanocrystalline Na3Sb domains is evidenced. During desodiation, Na3Sb domains convert into an amorphous phase. The chemical environment of Fe, probed by 57Fe Mo ssbauer spectroscopy, undergoes significant changes during the reaction. During sodiation, the well-resolved doublet of FeSb2 with an isomer shift around 0.45 mm s-1 and a quadrupole splitting of 1.26 mm s-1 is gradually converted into a doublet line centered at about 0.15 mm s1 along with a singlet line around 0 mm s-1. The former signal results from the formation of a Fe-rich FexSb alloy with an estimated composition of Fe4Sb while the latter signal corresponds to superparamagnetic Fe due to the formation of nanosized pure Fe domains. Interestingly the signal of Fe4Sb remains unaltered during desodiation. This mechanism is substantially different than that observed during the reaction with Li. The irreversible formation of a Fe-rich Fe4Sb alloy and the absence of full desodiation of Sb domains explain the lower than theoretical practical storage capacity.

  12. Irreversible altering of crystalline phase of phase-change Ge-Sb thin films

    SciTech Connect (OSTI)

    Krusin-Elbaum, L.; Shakhvorostov, D.; Cabral, C. Jr.; Raoux, S.; Jordan-Sweet, J. L.

    2010-03-22

    The stability of the crystalline phase of binary phase-change Ge{sub x}Sb{sub 1-x} films is investigated over a wide range of Ge content. From Raman spectroscopy we find the Ge-Sb crystalline structure irreversibly altered after exposure to a laser beam. We show that with increasing beam intensity/temperature Ge agglomerates and precipitates out in the amount growing with x. A simple empirical relation links Ge precipitation temperature T{sub Ge}{sup p} to the rate of change dT{sub cryst}/dx of crystallization, with the precipitation easiest on the mid-range x plateau, where T{sub cryst} is nearly constant. Our findings point to a preferable 15% < or approx. x < 50% window, that may achieve the desired cycling/archival properties of a phase-change cell.

  13. InAs quantum dot morphology after capping with In, N, Sb alloyed thin films

    SciTech Connect (OSTI)

    Keizer, J. G.; Koenraad, P. M.; Ulloa, J. M.; Utrilla, A. D.

    2014-02-03

    Using a thin capping layer to engineer the structural and optical properties of InAs/GaAs quantum dots (QDs) has become common practice in the last decade. Traditionally, the main parameter considered has been the strain in the QD/capping layer system. With the advent of more exotic alloys, it has become clear that other mechanisms significantly alter the QD size and shape as well. Larger bond strengths, surfactants, and phase separation are known to act on QD properties but are far from being fully understood. In this study, we investigate at the atomic scale the influence of these effects on the morphology of capped QDs with cross-sectional scanning tunneling microscopy. A broad range of capping materials (InGaAs, GaAsSb, GaAsN, InGaAsN, and GaAsSbN) are compared. The QD morphology is related to photoluminescence characteristics.

  14. Structural stability and electronic properties of InSb nanowires: A first-principles study

    SciTech Connect (OSTI)

    Zhang, Yong; Tang, Li-Ming Ning, Feng; Chen, Ke-Qiu; Wang, Dan

    2015-03-28

    Using first-principles calculations, we investigate the structural stability and electronic properties of InSb nanowires (NWs). The results show that, in contrast to the bulk InSb phase, wurtzite (WZ) NWs are more stable than zinc-blende (ZB) NWs when the NW diameter is smaller than 10 nm. Nonpassivated ZB and WZ NWs are found to be metallic and semiconducting, respectively. After passivation, both ZB and WZ NWs exhibit direct-gap semiconductor character, and the band gap magnitude of the NWs strongly depends on the suppression of surface states by the charge-compensation ability of foreign atoms to surface atoms. Moreover, the carrier mobility of the NW can be strengthened by halogen passivation.

  15. Funding Opportunity Announcement: Solar Bankability Data to Advance Transactions and Access (SB-DATA)

    Broader source: Energy.gov [DOE]

    The Solar Bankability Data to Advance Transactions and Access (SB-DATA) funding program targets soft cost reduction by increasing data accessibility and quality. It will facilitate the growth and expansion of the solar industry by creating a standardized data landscape for distributed solar. As the solar market continues to rapidly grow, it’s critical that the collection, management, and exchange of solar datasets across the value chain – especially those that affect the bankability of solar assets – are coordinated and streamlined to protect consumers, increase efficient pricing, and support new and existing businesses entering the solar marketplace. The goal of SB-DATA is to support the creation and adoption of industry-led open data standards for rapid and seamless data exchange across the value chain from origination to decommissioning.

  16. Doping Effects on the Thermoelectric Properties of Cu3SbSe4

    SciTech Connect (OSTI)

    Skoug, Eric; Cain, Jeffrey D.; Morelli, Donald; Majsztrik, Paul W; Kirkham, Melanie J; Lara-Curzio, Edgar

    2011-01-01

    We present the first systematic doping study on the ternary semiconductor Cu3SbSe 4 . We have developed a novel synthesis procedure that produces high-quality polycrystalline samples with hole concentrations an order of magnitude lower than have been reported for the undoped compound. The hole concentration can be increased by adding small amounts of either Ge or Sn on the Sb site. The power factor increases with increasing doping, reaching a maximum value of 16 W/cmK^2 . The thermoelectric properties are optimized for the 2% Sn doped compound which has ZT=0.72 at 630K, rivaling that of state-of-the-art thermoelectric materials in this temperature range.

  17. Chicago-St. Louis high speed rail plan

    SciTech Connect (OSTI)

    Stead, M.E.

    1994-12-31

    The Illinois Department of Transportation (IDOT), in cooperation with Amtrak, undertook the Chicago-St. Louis High Speed Rail Financial and Implementation Plan study in order to develop a realistic and achievable blueprint for implementation of high speed rail in the Chicago-St. Louis corridor. This report presents a summary of the Price Waterhouse Project Team`s analysis and the Financial and Implementation Plan for implementing high speed rail service in the Chicago-St. Louis corridor.

  18. DOE - Office of Legacy Management -- Fort St Vrain - 011

    Office of Legacy Management (LM)

    Fort St Vrain - 011 FUSRAP Considered Sites Site: Fort St Vrain (011) DOE Office of Environmental Management assumed the radioactive materials license for storage of spent nuclear fuel in 1999. Designated Name: Not Designated under FUSRAP Alternate Name: Fort St Vrain Independent Spent Fuel Storage Installation (ISFSI) Location: Platteville, Colorado Evaluation Year: Not considered for FUSRAP - in another program Site Operations: Nuclear power plant Site Disposition: Decommissioned in 1989 with

  19. Program Update: 1st Quarter 2009 | Department of Energy

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

    09 Program Update: 1st Quarter 2009 The Program Update newsletter is produced every quarter and highlights major activities and events that occurred across the DOE complex during that period of time. Office of Legacy Management (LM) Program Update, January-March 2009 (3.33 MB) More Documents & Publications Program Update: 1st Quarter 2011 Program Update: 1st Quarter 2010 Program Update: 2nd Quarter 2013

  20. Absorption properties of type-II InAs/InAsSb superlattices measured by spectroscopic ellipsometry

    SciTech Connect (OSTI)

    Webster, P. T.; Riordan, N. A.; Liu, S.; Zhang, Y.-H.; Johnson, S. R.; Steenbergen, E. H.

    2015-02-09

    Strain-balanced InAs/InAsSb superlattices offer access to the mid- to long-wavelength infrared region with what is essentially a ternary material system at the GaSb lattice constant. The absorption coefficients of InAs/InAsSb superlattices grown by molecular beam epitaxy on (100)-oriented GaSb substrates are measured at room temperature over the 30 to 800?meV photon energy range using spectroscopic ellipsometry, and the miniband structure of each superlattice is calculated using a Kronig-Penney model. The InAs/InAsSb conduction band offset is used as a fitting parameter to align the calculated superlattice ground state transition energy to the measured absorption onset at room temperature and to the photoluminescence peak energy at low temperature. It is observed that the ground state absorption coefficient and transition strength are proportional to the square of the wavefunction overlap and the ground state absorption coefficient approaches a maximum value of around 5780?cm{sup ?1} as the wavefunction overlap approaches 100%. The absorption analysis of these samples indicates that the optical joint density of states is weakly dependent on the period thickness and Sb content of the superlattice, and that wavefunction overlap is the principal design parameter in terms of obtaining strong absorption in these structures.

  1. Time-course analysis of the Shewanella amazonensis SB2B proteome in response to sodium chloride shock

    SciTech Connect (OSTI)

    Parnell, John J.; Callister, Stephen J.; Rompato, Giovanni; Nicora, Carrie D.; Pasa-Tolic, Ljiljana; Williamson, Ashley; Pfrender, Michael E.

    2011-06-29

    Organisms in the genus Shewanella have become models for response to environmental stress. One of the most important environmental stresses is change in osmolarity. In this study, we experimentally determine the response mechanisms of Shewanella amazonensis SB2B during osmotic stress. Osmotic stress in SB2B was induced through exposure to NaCl, and the time-course proteomics response was measured using liquid chromatography mass spectrometry. Protein trends were qualitatively compared to gene expression trends and to phenotypic characterization. Osmotic stress affects motility, and has also been associated with a change in the membrane fatty acid composition (due to induction of branched chain amino acid degradation pathways); however, we show this is not the case for SB2B. Although proteins and genes involved with branched chain amino acid degradation are induced, fatty acid degradation pathways are not induced and no change in the fatty acid profile occurs in SB2B as a result of osmotic shock. The most extensive response of SB2B over the time course of acclimation to high salt involves an orchestrated sequence of events comprising increased expression of signal transduction associated with motility and restricted cell division and DNA replication. After SB2B has switched to increased branched chain amino acid degradation, motility, and cellular replication proteins return to pre-perturbed levels.

  2. Two-dimensional topological crystalline insulator phase in Sb/Bi planar honeycomb with tunable Dirac gap

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hsu, Chia -Hsiu; Huang, Zhi -Quan; Crisostomo, Christian P.; Yao, Liang -Zi; Chuang, Feng -Chuan; Liu, Yu -Tzu; Wang, Baokai; Hsu, Chuang -Han; Lee, Chi -Cheng; Lin, Hsin; et al

    2016-01-14

    We predict planar Sb/Bi honeycomb to harbor a two-dimensional (2D) topological crystalline insulator (TCI) phase based on first-principles computations. Although buckled Sb and Bi honeycombs support 2D topological insulator (TI) phases, their structure becomes planar under tensile strain. The planar Sb/Bi honeycomb structure restores the mirror symmetry, and is shown to exhibit non-zero mirror Chern numbers, indicating that the system can host topologically protected edge states. Our computations show that the electronic spectrum of a planar Sb/Bi nanoribbon with armchair or zigzag edges contains two Dirac cones within the band gap and an even number of edge bands crossing themore » Fermi level. Lattice constant of the planar Sb honeycomb is found to nearly match that of hexagonal-BN. As a result, the Sb nanoribbon on hexagonal-BN exhibits gapped edge states, which we show to be tunable by an out-of the-plane electric field, providing controllable gating of edge state important for device applications.« less

  3. Federal laboratories for the 21st century

    SciTech Connect (OSTI)

    Gover, J.; Huray, P.G.

    1998-04-01

    Federal laboratories have successfully filled many roles for the public; however, as the 21st Century nears it is time to rethink and reevaluate how Federal laboratories can better support the public and identify new roles for this class of publicly-owned institutions. The productivity of the Federal laboratory system can be increased by making use of public outcome metrics, by benchmarking laboratories, by deploying innovative new governance models, by partnerships of Federal laboratories with universities and companies, and by accelerating the transition of federal laboratories and the agencies that own them into learning organizations. The authors must learn how government-owned laboratories in other countries serve their public. Taiwan`s government laboratory, Industrial Technology Research Institute, has been particularly successful in promoting economic growth. It is time to stop operating Federal laboratories as monopoly institutions; therefore, competition between Federal laboratories must be promoted. Additionally, Federal laboratories capable of addressing emerging 21st century public problems must be identified and given the challenge of serving the public in innovative new ways. Increased investment in case studies of particular programs at Federal laboratories and research on the public utility of a system of Federal laboratories could lead to increased productivity of laboratories. Elimination of risk-averse Federal laboratory and agency bureaucracies would also have dramatic impact on the productivity of the Federal laboratory system. Appropriately used, the US Federal laboratory system offers the US an innovative advantage over other nations.

  4. Proceedings of the 21st Seismic Research Symposium: Technologies...

    Office of Scientific and Technical Information (OSTI)

    Nuclear Test-Ban Treaty Citation Details In-Document Search Title: Proceedings of the 21st Seismic Research Symposium: Technologies for Monitoring The Comprehensive Nuclear ...

  5. DOE - Office of Legacy Management -- Fort St Vrain - 011

    Office of Legacy Management (LM)

    Site Disposition: Radioactive Materials Handled: Primary Radioactive Materials ... Vrains spent nuclear fuel. Originally, Fort St. Vrain was a nuclear power generating ...

  6. St. Mary's County, Maryland: Energy Resources | Open Energy Informatio...

    Open Energy Info (EERE)

    Zone Subtype A. Places in St. Mary's County, Maryland California, Maryland Charlotte Hall, Maryland Golden Beach, Maryland Leonardtown, Maryland Lexington Park, Maryland...

  7. St. Clair County, Michigan: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Marine City, Michigan Marysville, Michigan Memphis, Michigan Pearl Beach, Michigan Port Huron, Michigan Richmond, Michigan St. Clair, Michigan Yale, Michigan Retrieved from...

  8. Texas's 21st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Companies in Texas's 21st congressional district Texas General Land Office Retrieved from "http:en.openei.orgwindex.php?titleTexas%27s21stcongressionaldistrict&oldid204390...

  9. Maine's 1st congressional district: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Companies in Maine's 1st congressional district Central Maine Power Co Retrieved from "http:en.openei.orgwindex.php?titleMaine%27s1stcongressionaldistrict&oldid192967...

  10. Louisiana's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    in Louisiana's 1st congressional district Entergy New Orleans Inc Retrieved from "http:en.openei.orgwindex.php?titleLouisiana%27s1stcongressionaldistrict&oldid192537...

  11. Washington's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    in Washington's 1st congressional district Snohomish County PUD No 1 Retrieved from "http:en.openei.orgwindex.php?titleWashington%27s1stcongressionaldistrict&oldid189772...

  12. MIT- Center for 21st Century Energy | Open Energy Information

    Open Energy Info (EERE)

    Name: MIT- Center for 21st Century Energy Address: 77 Massachusetts Avenue Place: Cambridge, Massachusetts Zip: 02139 Region: Greater Boston Area Website: web.mit.educ21ce...

  13. Florida's 21st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Florida's 21st congressional district Biodiesel of South Florida LLC Biofuels Digest Cambridge Project Development Caribbean Energy Resources Corp ClimeCo Corporation Electron...

  14. Texas's 1st congressional district: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Energy Companies in Texas's 1st congressional district Eisenbach Consulting NM Invest Retrieved from "http:en.openei.orgwindex.php?titleTexas%27s1stcongressionaldis...

  15. The 21st International Conference on Laser Spectroscopy - ICOLS 2013

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

    The 21st International Conference on Laser Spectroscopy - ICOLS 2013 http://icols.berkeley.edu/ June 9-14, 2013; Berkeley, CA

  16. Laboratories for the 21st Century Case Studies

    Broader source: Energy.gov [DOE]

    These case studies feature examples of energy-efficient laboratories for the 21st century. The Featured Concepts Table outlines technologies covered in each case study.

  17. St. Kitts and Nevis-Caribbean Community (CARICOM) Sustainable...

    Open Energy Info (EERE)

    Kitts and Nevis-Caribbean Community (CARICOM) Sustainable Energy Roadmap and Strategy Jump to: navigation, search Name St. Kitts and Nevis-Caribbean Community (CARICOM) Sustainable...

  18. The 21st International Conference on Laser Spectroscopy - ICOLS...

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

    The 21st International Conference on Laser Spectroscopy - ICOLS 2013 http:icols.berkeley.edu June 9-14, 2013; Berkeley, CA

  19. West Virginia's 1st congressional district: Energy Resources...

    Open Energy Info (EERE)

    You can help OpenEI by expanding it. This page represents a congressional district in West Virginia. Registered Research Institutions in West Virginia's 1st congressional...

  20. Washington University in St. Louis | OSTI, US Dept of Energy...

    Office of Scientific and Technical Information (OSTI)

    Career Award I-CARES Director, Himadri Pakrasi DOE awards 2 million to design a battery management system for electric cars Washington People: Tiffany Knight About WUSTL & St. ...

  1. Water Sampling At Mt St Helens Area (Shevenell & Goff, 1995)...

    Open Energy Info (EERE)

    Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Water Sampling At Mt St Helens Area (Shevenell & Goff, 1995) Exploration Activity Details...

  2. Iowa's 1st congressional district: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    in Iowa. Registered Energy Companies in Iowa's 1st congressional district Clinton County Bio Energy LLC Natural Solutions Waverly Light and Power Retrieved from "http:...

  3. Nevada's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Energy Companies in Nevada's 1st congressional district Algodyne Ethanol Energy Inc Bio Solutions Manufacturing Inc Innovative Energy Solutions Inc Li ion Motors Corp formerly...

  4. New Hampshire's 1st congressional district: Energy Resources...

    Open Energy Info (EERE)

    New Hampshire. Registered Energy Companies in New Hampshire's 1st congressional district Bio Energy US New Hampshire Cate Street Capital Inc Environmental Power Corp Eolian...

  5. St. Mary Parish, Louisiana: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    A. Places in St. Mary Parish, Louisiana Amelia, Louisiana Baldwin, Louisiana Bayou Vista, Louisiana Berwick, Louisiana Charenton, Louisiana Franklin, Louisiana Morgan City,...

  6. St. Clair County, Missouri: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Missouri Gerster, Missouri Lowry City, Missouri Osceola, Missouri Roscoe, Missouri Vista, Missouri Retrieved from "http:en.openei.orgwindex.php?titleSt.ClairCounty,Mis...

  7. Utah's 1st congressional district: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Energy Companies in Utah's 1st congressional district Blue Source LLC Ciralight Emery Energy Company Eneco Inc EnergySolutions Inc Genifuel Green Joules GreenFire Energy...

  8. St. George, Maine: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    St. George, Maine: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 44.0164709, -69.1989341 Show Map Loading map... "minzoom":false,"mappingserv...

  9. Food and Fuel for the 21st Century

    Broader source: Energy.gov [DOE]

    Food and Fuel for the 21st Century held its annual symposium March 12–13, 2015, at Atkinson Hall, University of California San Diego.

  10. North Carolina's 1st congressional district: Energy Resources...

    Open Energy Info (EERE)

    You can help OpenEI by expanding it. This page represents a congressional district in North Carolina. Registered Policy Organizations in North Carolina's 1st congressional...

  11. Job Creation and Energy Savings in St. Paul, Minnesota

    Broader source: Energy.gov [DOE]

    Check out this video where Mayor Chris Coleman explains how St. Paul is using grant money to create jobs while cutting waste and saving energy.

  12. City of St Clairsville, Ohio (Utility Company) | Open Energy...

    Open Energy Info (EERE)

    Clairsville, Ohio (Utility Company) Jump to: navigation, search Name: City of St Clairsville Place: Ohio Website: www.stclairsville.comassist.s Outage Hotline: 740.695.0123...

  13. St. Johns County, Florida: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 2 Climate Zone Subtype A. Places in St. Johns County, Florida Butler Beach, Florida Crescent Beach, Florida Fruit Cove, Florida Hastings, Florida...

  14. St. Clair County, Alabama: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 3 Climate Zone Subtype A. Places in St. Clair County, Alabama Argo, Alabama Ashville, Alabama Leeds, Alabama Margaret, Alabama Moody, Alabama Odenville,...

  15. Ohio's 1st congressional district: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    RBI Solar Inc SEMCO THOR Turner Hunt Ocean Renewable LLC The Utilities Group Inc Vision Energy Energy Generation Facilities in Ohio's 1st congressional district Melink Solar...

  16. Maryland's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    in Maryland. Registered Energy Companies in Maryland's 1st congressional district Gore Fuel Cell Technologies Maryland Biodiesel Retrieved from "http:en.openei.orgw...

  17. Minnesota's 1st congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    1st congressional district Agra Resources Cooperative EXOL Agri Energy LLC Corn Plus High Country Energy Juhl Wind Inc MinnErgy LLC Minwind Energy LLC Next Generation...

  18. St. Tammany Parish, Louisiana: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Madisonville, Louisiana Mandeville, Louisiana Pearl River, Louisiana Slidell, Louisiana Sun, Louisiana Retrieved from "http:en.openei.orgwindex.php?titleSt.TammanyParish,L...

  19. Vehicle Technologies Office: 21st Century Truck Partnership | Department of

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

    Energy 21st Century Truck Partnership Vehicle Technologies Office: 21st Century Truck Partnership Logo for 21st Century Truck Partnership. Partial outline of three various size medium to heavy-duty trucks followed by the words, 21st Century Truck Partnership. Medium-duty and heavy-duty trucks play a vital role in moving freight and passengers, serving as the backbone of America's economy. These trucks also play essential roles in other parts of society, such as maintaining our electricity

  20. City of St James, Minnesota (Utility Company) | Open Energy Informatio...

    Open Energy Info (EERE)

    St James Place: Minnesota Phone Number: (507) 375-3241 Website: www.ci.stjames.mn.usindex.asp Twitter: @cityofstjames Facebook: https:www.facebook.compages...

  1. City of St James, Missouri (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    St James Place: Missouri Phone Number: 573-265-7011 or 573.265.7013 Website: stjamesmo.orgindex.phpdepart Facebook: https:www.facebook.comstjamesmo Outage Hotline:...

  2. City of St Paul, Nebraska (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    Paul, Nebraska (Utility Company) Jump to: navigation, search Name: City of St Paul Place: Nebraska Phone Number: 308.754.4661 Website: www.stpaulnebraska.comlive-he Outage...

  3. North St. Paul, Minnesota: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    St. Paul, Minnesota: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 45.0124657, -92.9918828 Show Map Loading map... "minzoom":false,"mappingse...

  4. Vehicle Technologies Office: 21st Century Truck Technical Goals

    Broader source: Energy.gov [DOE]

    The 21st Century Truck Partnership aims to improve fuel efficiency in heavy trucks through improvements in engine efficiency, aerodynamics, and rolling resistance.

  5. 21st Century Truck Partnership Roadmap Roadmap and Technical...

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

    Roadmap Roadmap and Technical White Papers - 21CTP-0003, December 2006 21st Century Truck Partnership Roadmap Roadmap and Technical White Papers - 21CTP-0003, December 2006 Report ...

  6. 21st Century Truck Partnership - Roadmap and Technical White...

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

    - Roadmap and Technical White Papers Appendix of Supporting Information - 21CTP-0003, December 2006 21st Century Truck Partnership - Roadmap and Technical White Papers Appendix of ...

  7. Aeromagnetic Survey At Mt St Helens Area (Towle, 1983) | Open...

    Open Energy Info (EERE)

    structure of Mount St. Helens in more detail. Electrical and electromagnetic methods would be especially useful in determining the actual electrical conductivity of...

  8. St. Martin Parish, Louisiana: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Broussard, Louisiana Cecilia, Louisiana Henderson, Louisiana Morgan City, Louisiana Parks, Louisiana St. Martinville, Louisiana Retrieved from "http:en.openei.orgw...

  9. Gain and tuning characteristics of mid-infrared InSb quantum dot diode lasers

    SciTech Connect (OSTI)

    Lu, Q.; Zhuang, Q.; Hayton, J.; Yin, M.; Krier, A.

    2014-07-21

    There have been relatively few reports of lasing from InSb quantum dots (QDs). In this work, type II InSb/InAs QD laser diodes emitting in the mid-infrared at 3.1??m have been demonstrated and characterized. The gain was determined to be 2.9?cm{sup ?1} per QD layer, and the waveguide loss was ?15?cm{sup ?1} at 4?K. Spontaneous emission measurements below threshold revealed a blue shift of the peak wavelength with increasing current, indicating filling of ground state heavy hole levels in the QDs. The characteristic temperature, T{sub 0}?=?101?K below 50?K, but decreased to 48?K at higher temperatures. The emission wavelength of these lasers showed first a blue shift followed by a red shift with increasing temperature. A hybrid structure was used to fabricate the laser by combining a liquid phase epitaxy grown p-InAs{sub 0.61}Sb{sub 0.13}P{sub 0.26} lower cladding layer and an upper n{sup +} InAs plasmon cladding layer which resulted in a maximum operating temperature (T{sub max}) of 120?K in pulsed mode, which is the highest reported to date.

  10. Interband magneto-spectroscopy in InSb square and parabolic quantum wells

    SciTech Connect (OSTI)

    Kasturiarachchi, T.; Edirisooriya, M.; Mishima, T. D.; Doezema, R. E.; Santos, M. B.; Saha, D.; Pan, X.; Sanders, G. D.; Stanton, C. J.

    2015-06-07

    We measure the magneto-optical absorption due to intersubband optical transitions between conduction and valence subband Landau levels in InSb square and parabolic quantum wells. InSb has the narrowest band gap (0.24 eV at low temperature) of the III–V semiconductors leading to a small effective mass (0.014 m{sub 0}) and a large g–factor (−51). As a result, the Landau level spacing is large at relatively small magnetic fields (<8 T), and one can observe spin-splitting of the Landau levels. We examine two structures: (i) a multiple-square-well structure and (ii) a structure containing multiple parabolic wells. The energies and intensities of the strongest features are well explained by a modified Pidgeon-Brown model based on an 8-band k•p model that explicitly incorporates pseudomorphic strain. The strain is essential for obtaining agreement between theory and experiment. While modeling the square well is relatively straight-forward, the parabolic well consists of 43 different layers of various thickness to approximate a parabolic potential. Agreement between theory and experiment for the parabolic well validates the applicability of the model to complicated structures, which demonstrates the robustness of our model and confirms its relevance for developing electronic and spintronic devices that seek to exploit the properties of the InSb band structure.

  11. Vacancy structures and melting behavior in rock-salt GeSbTe

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Bin; Wang, Xue -Peng; Shen, Zhen -Ju; Li, Xian -Bin; Wang, Chuan -Shou; Chen, Yong -Jin; Li, Ji -Xue; Zhang, Jin -Xing; Zhang, Ze; Zhang, Sheng -Bai; et al

    2016-05-03

    Ge-Sb-Te alloys have been widely used in optical/electrical memory storage. Because of the extremely fast crystalline-amorphous transition, they are also expected to play a vital role in next generation nonvolatile microelectronic memory devices. However, the distribution and structural properties of vacancies have been one of the key issues in determining the speed of melting (or amorphization), phase-stability, and heat-dissipation of rock-salt GeSbTe, which is crucial for its technological breakthrough in memory devices. Using spherical aberration-aberration corrected scanning transmission electron microscopy and atomic scale energy-dispersive X-ray mapping, we observe a new rock-salt structure with high-degree vacancy ordering (or layered-like ordering) atmore » an elevated temperature, which is a result of phase transition from the rock-salt phase with randomly distributed vacancies. First-principles calculations reveal that the phase transition is an energetically favored process. Furthermore, molecular dynamics studies suggest that the melting of the cubic rock-salt phases is initiated at the vacancies, which propagate to nearby regions. The observation of multi-rock-salt phases suggests another route for multi-level data storage using GeSbTe.« less

  12. Science in St. Louis | Dr. Benjamin Kumfer | Photosynthetic Antenna

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

    Research Center Benjamin Kumfer Science in St. Louis | Dr. Benjamin Kumfer An Introduction to Carbon Capture, Utilization, and Storage December 8, 2015 - 7:00pm Jamestown Bluffs Branch, St. Louis County Library, 4153 N. Highway 67 Florissant, MO

  13. Ultrathin body GaSb-on-insulator p-channel metal-oxide-semiconductor field-effect transistors on Si fabricated by direct wafer bonding

    SciTech Connect (OSTI)

    Yokoyama, Masafumi Takenaka, Mitsuru; Takagi, Shinichi; Yokoyama, Haruki

    2015-02-16

    We have realized ultrathin body GaSb-on-insulator (GaSb-OI) on Si wafers by direct wafer bonding technology using atomic-layer deposition (ALD) Al{sub 2}O{sub 3} and have demonstrated GaSb-OI p-channel metal-oxide-semiconductor field-effect transistors (p-MOSFETs) on Si. A 23-nm-thick GaSb-OI p-MOSFET exhibits the peak effective mobility of ∼76 cm{sup 2}/V s. We have found that the effective hole mobility of the thin-body GaSb-OI p-MOSFETs decreases with a decrease in the GaSb-OI thickness or with an increase in Al{sub 2}O{sub 3} ALD temperature. The InAs passivation of GaSb-OI MOS interfaces can enhance the peak effective mobility up to 159 cm{sup 2}/V s for GaSb-OI p-MOSFETs with the 20-nm-thick GaSb layer.

  14. Optical properties of amorphous and crystalline Sb-doped SnO{sub 2} thin films studied with spectroscopic ellipsometry: Optical gap energy and effective mass

    SciTech Connect (OSTI)

    So, Hyeon Seob; Park, Jun-Woo; Jung, Dae Ho; Ko, Kun Hee; Lee, Hosun

    2015-08-28

    We investigated the optical properties of amorphous and crystalline antimony (Sb)-doped tin dioxide (SnO{sub 2}) thin films grown using the co-sputtering deposition method at room temperature. We used undoped and Sb-doped (8 wt. %) SnO{sub 2} targets. Varying the relative power ratio of the two targets, we controlled the Sb-composition of the SnO{sub 2}:Sb thin films up to 2.3 at. % of Sb contents. Through annealing, the as-grown amorphous SnO{sub 2}:Sb thin films were transformed to crystalline thin films. Dielectric functions were obtained from the measured ellipsometry angles, Ψ and Δ, using the Drude and parametric optical constant models. We determined the absorption coefficients and optical gap energies of the SnO{sub 2}:Sb thin films from the dielectric functions. We found increasing optical gap energy with increasing Sb composition. Increases in the Drude tail amplitudes, a signature of free carrier concentrations, were found in annealed, crystalline thin films with increasing Sb composition. The increase in the optical gap energy with increasing Sb composition was mainly attributed to the Burstein-Moss effect. Using Hall effect measurements, we obtained Hall carrier concentrations (N{sub Hall}) and electron Hall mobilities (μ{sub Hall}). The carrier concentrations and mobilities increased from 2.6 × 10{sup 19 }cm{sup −3} and 1.0 cm{sup 2}/(V s) to 2.0 × 10{sup 20 }cm{sup −1} and 7.2 cm{sup 2}/(V s), respectively, with increasing Sb contents. This result suggests that the nominally undoped SnO{sub 2} films are unintentionally n-type doped. Assuming that the N{sub Hall} and optical carrier concentrations (N{sub opt}) were the same, we obtained the effective masses of the SnO{sub 2}:Sb thin films with increasing Sb compositions. The effective masses of the SnO{sub 2}:Sb thin films increased from 0.245 m{sub 0} to 0.4 m{sub 0} with increasing Sb doping contents, and the nonparabolicity of the conduction band was estimated. We

  15. Using galvanostatic electroforming of Bi1–xSbx nanowires to control composition, crystallinity, and orientation

    SciTech Connect (OSTI)

    Limmer, Steven J.; Medlin, Douglas L.; Siegal, Michael P.; Hekmaty, Michelle; Lensch-Falk, Jessica L.; Erickson, Kristopher; Pillars, Jamin; Yelton, W. Graham

    2014-12-03

    When using galvanostatic pulse deposition, we studied the factors influencing the quality of electroformed Bi1–xSbx nanowires with respect to composition, crystallinity, and preferred orientation for high thermoelectric performance. Two nonaqueous baths with different Sb salts were investigated. The Sb salts used played a major role in both crystalline quality and preferred orientations. Nanowire arrays electroformed using an SbI3 -based chemistry were polycrystalline with no preferred orientation, whereas arrays electroformed from an SbCl3-based chemistry were strongly crystallographically textured with the desired trigonal orientation for optimal thermoelectric performance. From the SbCl3 bath, the electroformed nanowire arrays were optimized to have nanocompositional uniformity, with a nearly constant composition along the nanowire length. Moreover, nanowires harvested from the center of the array had an average composition of Bi0.75 Sb0.25. However, the nanowire compositions were slightly enriched in Sb in a small region near the edges of the array, with the composition approaching Bi0.70Sb0.30.

  16. In-situ characterization of the optical and electronic properties in GeTe and GaSb thin films

    SciTech Connect (OSTI)

    Velea, A.; Popescu, M.; Galca, A. C.; Socol, G.

    2015-10-07

    GeTe and GaSb thin films obtained by pulsed laser deposition were investigated by spectroscopic ellipsometry at controlled temperatures. The GeTe films were fully amorphous, while the GaSb films were partially crystalized in the as-deposited state. The Tauc-Lorentz model was employed to fit the experimental data. From the temperature study of the optical constants, it was observed the crystallization in the 150–160 °C range of GeTe amorphous films and between 230 and 240 °C of GaSb amorphous phase. A second transition in the resonance energy and the broadening parameter of the Lorentz oscillator was observed due to the crystallization of Sb after 250 °C. The temperatures of 85 °C and 130 °C are noticed as the start of the relaxation of the amorphous GeTe phase and as-deposited GaSb. The peaks of the imaginary part of the dielectric function red shifted after the phase change, while the variation with temperature of the crystalline phase follows the Varshni law. The electron-phonon coupling constants are 2.88 and 1.64 for c-GeTe and c-GaSb, respectively. An optical contrast up to 60% was obtained for GeTe films and a maximum value of 7.5% is revealed in the case GaSb, which is altered by the partial crystallinity of the as-deposited films.

  17. Microstructural evaluation of Sb-adjusted Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} buffer layer systems for IR applications

    SciTech Connect (OSTI)

    Chen, E.; Paine, D.C.; Uppal, P.; Ahearn, J.S.; Nichols, K.; Charache, G.W.

    1998-06-01

    The authors report on a transmission electron microscopy (TEM) study of Sb-adjusted quaternary Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} buffer-layers grown on <001> GaAs substrates. A series of structures were grown by MBE at 470 C that utilize a multilayer grading scheme in which the Sb content of Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} buffer-layers grown on <001> GaAs substrates. A series of structures were grown by MBe at 470 C that utilize a multilayer grading scheme in which the Sb content of Al{sub 0.5}Ga{sub 0.5}As{sub 1{minus}y}Sb{sub y} is successively increased in a series of 125 nm thick layers. Post growth analysis using conventional bright field and weak beam dark field imaging of these buffer layers in cross-section reveals that the interface misfit dislocations are primarily of the 60{degree} type and are distributed through out the interfaces of the buffer layer. When optimized, the authors have shown, using plan view and cross-sectional TEM, that this approach can reduce the threading defect density to below the detectability limit of TEM (< 10{sup 5}/cm{sup 2}) and preserve growth surface planarity. The Sb-graded approach was used to fabricate two 2.2 {micro}m power converter structures fabricated using InGaAs grown on Sb-based buffer layers on GaAs substrates. A microstructural and electrical characterization was performed on these device structures and the results are contrasted with a sample in which InP was selected as the substrate. Microstructure, defect density and device performance in these not-yet-optimized Sb-based buffer layers compares favorably to equivalent devices fabricated using InP substrates.

  18. St. Louis Airport site environmental report for calendar year 1989, St. Louis, Missouri

    SciTech Connect (OSTI)

    none,

    1990-05-01

    The environmental monitoring program, which began in 1984, continued during 1989 at the St. Louis Airport Site (SLAPS) in St. Louis County, Missouri. SLAPS and its vicinity properties, including ditches north and south of the site, were designated for cleanup as part of the Formerly Utilized Sites Remedial Action Program (FUSRAP), a United States Department of Energy (DOE) program to identify and decontaminate or otherwise control sites where residual radioactive material remains from the early years of the nation's atomic energy program. The monitoring program at SLAPS measures radon concentrations in air; external gamma dose rates; and uranium, thorium, and radium concentrations in surface water, groundwater, and sediment. Additionally, several nonradiological parameters are measured in groundwater. To assess the potential effect of SLAPS on public health, the potential radiation dose was estimated for a hypothetical maximally exposed individual. This report presents the findings of the environmental monitoring program conducted at the St. Louis Airport Site (SLAPS) during calendar year 1989. 19 refs., 13 figs., 14 tabs.

  19. Investigation of high hole mobility In{sub 0.41}Ga{sub 0.59}Sb/Al{sub 0.91}Ga{sub 0.09}Sb quantum well structures grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Wang, Juan; Xing, Jun-Liang; Xiang, Wei; Wang, Guo-Wei; Xu, Ying-Qiang; Ren, Zheng-Wei; Niu, Zhi-Chuan

    2014-02-03

    Modulation-doped In{sub 0.41}Ga{sub 0.59}Sb/Al{sub 0.91}Ga{sub 0.09}Sb quantum-well (QW) structures were grown by molecular beam epitaxy. Cross-sectional transmission electron microscopy and atomic force microscopy studies show high crystalline quality and smooth surface morphology. X-ray diffraction investigations confirm 1.94% compressive strain within In{sub 0.41}Ga{sub 0.59}Sb channel. High room temperature hole mobility with high sheet density of 1000 cm{sup 2}/Vs, 0.877??10{sup 12}/cm{sup 2}, and 965 cm{sup 2}/Vs, 1.112??10{sup 12}/cm{sup 2} were obtained with different doping concentrations. Temperature dependent Hall measurements show different scattering mechanisms on hole mobility at different temperature range. The sheet hole density keeps almost constantly from 300?K to 77?K. This study shows great potential of In{sub 0.41}Ga{sub 0.59}Sb/Al{sub 0.91}Ga{sub 0.09}Sb QW for high-hole-mobility device applications.

  20. Roadmap and Technical White Papers for 21st Century Truck Partnership...

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

    Roadmap and Technical White Papers for 21st Century Truck Partnership Roadmap and Technical White Papers for 21st Century Truck Partnership Roadmap document for 21st Century Truck ...

  1. Superconductivity in strong spin orbital coupling compound Sb2Se3

    SciTech Connect (OSTI)

    Kong, P. P.; Sun, F.; Xing, L. Y.; Zhu, J.; Zhang, S. J.; Li, W. M.; Liu, Q. Q.; Wang, X. C.; Feng, S. M.; Yu, X. H.; Zhu, J. L.; Yu, R. C.; Yang, W. G.; Shen, G. Y.; Zhao, Y. S.; Ahuja, R.; Mao, H. K.; Jin, C. Q.

    2014-10-20

    Recently, A2B3 type strong spin orbital coupling compounds such as Bi2Te3, Bi2Se3 and Sb2Te3 were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb2Se3 on the other hand was found to be topological trivial, but theoretical studies indicated that the pressure might induce Sb2Se3 into a topological nontrivial state. We report on the discovery of superconductivity in Sb2Se3 single crystal induced via pressure. Our experiments indicated that Sb2Se3 became superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition at ~3 GPa which should be related to the topological quantum transition. The superconducting transition temperature (TC) increased to around 8.0 K with pressure up to 40 GPa while it keeps ambient structure. As a result, high pressure Raman revealed that new modes appeared around 10 GPa and 20 GPa, respectively, which correspond to occurrence of superconductivity and to the change of TC slop as the function of high pressure in conjunction with the evolutions of structural parameters at high pressures.

  2. Characterization of Cr-rich Cr-Sb multilayer films: Syntheses of a new metastable phase using modulated elemental reactants

    SciTech Connect (OSTI)

    Regus, Matthias; Mankovsky, Sergiy; Polesya, Svitlana; Kuhn, Gerhard; Ditto, Jeffrey; Schürmann, Ulrich; Jacquot, Alexandre; Bartholomé, Kilian; Näther, Christian; Winkler, Markus; König, Jan D.; Böttner, Harald; Kienle, Lorenz; Johnson, David C.; Ebert, Hubert; Bensch, Wolfgang

    2015-10-15

    The new metastable compound Cr{sub 1+x}Sb with x up to 0.6 has been prepared via a thin film approach using modulated elemental reactants and investigated by in-situ X-ray reflectivity, X-ray diffraction, differential scanning calorimetry, energy dispersive X-ray analysis as well as transmission electron microscopy and atomic force microscopy. The new Cr-rich antimonide crystallizes in a structure related to the Ni{sub 2}In-type structure, where the crystallographic position (1/3, 2/3, 3/4) is partially occupied by excess Cr. The elemental layers of the pristine material interdiffused significantly before Cr{sub 1+x}Sb crystallized. A change in the activation energy was observed for the diffusion process when crystal growth starts. First-principles electronic structure calculations provide insight into the structural stability, magnetic properties and resistivity of Cr{sub 1+x}Sb. - Graphical abstract: 1 amorphous multilayered film 2 interdiffused amorphous film 3 metastable crystalline phase 4 thermodynamic stable phase (and by-product). - Highlights: • Interdiffusion of amorphous Cr and Sb occurs before crystallization. • Crystallization of a new metastable phase Cr{sub 1.6}Sb in Ni{sub 2}In-type structure. • The new Cr-rich phase shows half-metallic behavior.

  3. High thermal stability Sb{sub 3}Te-TiN{sub 2} material for phase change memory application

    SciTech Connect (OSTI)

    Ji, Xinglong; Zhou, Wangyang; Wu, Liangcai Zhu, Min; Rao, Feng; Song, Zhitang; Cao, Liangliang; Feng, Songlin

    2015-01-12

    For phase change memory (PCM) applications, it has been widely accepted that δ phase Sb-Te has fast operation speed and good phase stability. However, the fast growth crystallization mechanism will cause poor amorphous phase stability and overlarge grain size. We introduce TiN{sub 2} into δ phase Sb-Te (Sb{sub 3}Te) to enhance the amorphous thermal stability and refine the grain size. With TiN{sub 2} incorporating, the temperature for 10-year data retention increases from 79 °C to 124 °C. And the grain size decreases to dozens of nanometers scale. Based on X-ray photoelectron spectroscopy and transmission electron microscopy results, we knew that nitrogen atoms bond with titanium, forming disorder region at the grain boundary of Sb{sub 3}Te-TiN{sub 2} (STTN). Thus, STTN has a quite different crystallization mechanism from Sb{sub 3}Te. Furthermore, PCM device based on STTN can realize reversible phase change under 20 ns electrical pulse.

  4. Unusual magnetic hysteresis and the weakened transition behavior induced by Sn substitution in Mn{sub 3}SbN

    SciTech Connect (OSTI)

    Sun, Ying, E-mail: sunying@buaa.edu.cn [Center for Condensed Matter and Materials Physics, Department of Physics, Beihang University, Beijing 100191 (China); International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Guo, Yanfeng; Li, Jun; Wang, Xia [Superconducting Properties Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Tsujimoto, Yoshihiro [Materials Processing Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan); Wang, Cong [Center for Condensed Matter and Materials Physics, Department of Physics, Beihang University, Beijing 100191 (China); Feng, Hai L.; Sathish, Clastin I.; Yamaura, Kazunari, E-mail: yamaura.kazunari@nims.go.jp [Superconducting Properties Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Matsushita, Yoshitaka [Analysis Station, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan)

    2014-01-28

    Substitution of Sb with Sn was achieved in ferrimagnetic antiperovskite Mn{sub 3}SbN. The experimental results indicate that with an increase in Sn concentration, the magnetization continuously decreases and the crystal structure of Mn{sub 3}Sb{sub 1-x}Sn{sub x}N changes from tetragonal to cubic phase at around x of 0.8. In the doping series, step-like anomaly in the isothermal magnetization was found and this behavior was highlighted at x?=?0.4. The anomaly could be attributed to the magnetic frustration, resulting from competition between the multiple spin configurations in the antiperovskite lattice. Meantime, H{sub c} of 18 kOe was observed at x?=?0.3, which is probably the highest among those of manganese antiperovskite materials reported so far. With increasing Sn content, the abrupt change of resistivity and the sharp peak of heat capacity in Mn{sub 3}SbN were gradually weakened. The crystal structure refinements indicate the weakened change at the magnetic transition is close related to the change of c/a ratio variation from tetragonal to cubic with Sn content. The results derived from this study indicate that the behavior of Mn{sub 3}Sb{sub 1-x}Sn{sub x}N could potentially enhance its scientific and technical applications, such as spin torque transfer and hard magnets.

  5. DOE/BES Workshop on Clean and Efficient Combustion of 21st Century...

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

    DOEBES Workshop on Clean and Efficient Combustion of 21st Century Transportation Fuels DOEBES Workshop on Clean and Efficient Combustion of 21st Century Transportation Fuels ...

  6. Hybridized Nature of Pseudogap in Kondo Insulators CeRhSb and CeRhAs

    SciTech Connect (OSTI)

    Kumigashira, H.; Takahashi, T.; Yoshii, S.; Kasaya, M.

    2001-08-06

    We studied the electronic structure of Kondo insulators CeRhSb and CeRhAs using high-resolution photoemission spectroscopy. We found that the 4f -derived density of states shows a depletion (pseudogap) at E{sub F} in contrast to metallic Kondo materials. It was found that the size of the f pseudogap is smaller than that of conduction electrons (c pseudogap) while both scale well with the Kondo temperature. The present results indicate that the hybridization between 4f and conduction electrons near E{sub F} is essential for the Kondo gap in the Ce-based compounds.

  7. Hybrid Back Surface Reflector GaInAsSb Thermophotovoltaic Devices

    SciTech Connect (OSTI)

    RK Huang; CA Wang; MK Connors; GW Turner; M Dashiell

    2004-05-11

    Back surface reflectors have the potential to improve thermophotovoltaic (TPV) device performance though the recirculation of infrared photons. The ''hybrid'' back-surface reflector (BSR) TPV cell approach allows one to construct BSRs for TPV devices using conventional, high efficiency, GaInAsSb-based TPV material. The design, fabrication, and measurements of hybrid BSR-TPV cells are described. The BSR was shown to provide a 4 mV improvement in open-circuit voltage under a constant shortcircuit current, which is comparable to the 5 mV improvement theoretically predicted. Larger improvements in open-circuit voltage are expected in the future with materials improvements.

  8. Production and properties of Si-SiO2-In Sb structures

    SciTech Connect (OSTI)

    Padalko, A.G.; Kotov, B.A.; Lazarev, V.B.; Sukharev, V.I.; Volkov, V.V.

    1985-10-01

    When MIS structures are formed by pyrolysis of silane with subsequent thermal oxidation of the film of polycrystalline silicon on sapphire and with oriented crystallization of thin layers of an indium antimonide melt on the produced structures, the highly doped silicon-silicon dioxide-InSb has a concentration of majority charge carriers of (2-5) . 10/sup 15/ cm/sup -9/ with a density of surface states of (2-8) . 10/sup 11/ ev/sup -1/ . cm/sup -2/.

  9. Torsional fatigue model for limitorque type SMB/SB/SBD actuators for motor-operated valves

    SciTech Connect (OSTI)

    Somogyi, D.; Alvarez, P.D.; Kalsi, M.S.

    1996-12-01

    Kalsi Engineering, Inc. has recently developed a computer program to predict the torsional fatigue life of Limitorque Type SMB/SB/SBD actuators for motor-operated valves under given loading levels, including those that exceed the ratings. The development effort was an outgrowth of the {open_quote}Thrust Rating Increase{close_quote} test program. The fatigue model computes all pertinent stress components and their variations as a function of the loading ramp. The cumulative damage and fatigue life due to stress cycling is computed by use of a modification of Miner`s rule. Model predictions were validated against actual cyclic loading test results.

  10. Pairing phenomenon in doubly odd neutron rich {sup 136}Sb nucleus

    SciTech Connect (OSTI)

    Laouet, N.; Benrachi, F.

    2012-06-27

    Based on p-n and n-n pairing gap energies giving by K. Kaneko et al. (2003), we make modifications on the kh5082 interaction. Calculations and study of some nuclear properties for {sup 136}Sb nucleus are developed in the framework of the nuclear shell model by means of OXBASH structure code. We get the same energetic sequence as the recent experimental values of single particle energies. The effective charge values e{sub p}=1.35e and e{sub n}=0.9e, and factors given by V. I. Isakov are used to evaluate multipole electromagnetic moments.