National Library of Energy BETA

Sample records for transitional depth structures

  1. Depth-resolved magnetic and structural analysis of relaxing epitaxial...

    Office of Scientific and Technical Information (OSTI)

    Depth-resolved magnetic and structural analysis of relaxing epitaxial Sr 2 CrReO 6 <...

  2. Structural Phase Transition and Photoluminescence Properties...

    Office of Scientific and Technical Information (OSTI)

    Phase Transition and Photoluminescence Properties of YF3:Eu3+ Nanocrystals under High Pressure Citation Details In-Document Search Title: Structural Phase Transition and ...

  3. STARSPOTS-TRANSIT DEPTH RELATION OF THE EVAPORATING PLANET CANDIDATE KIC 12557548b

    SciTech Connect (OSTI)

    Kawahara, Hajime; Kurosaki, Kenji; Ito, Yuichi; Ikoma, Masahiro; Hirano, Teruyuki

    2013-10-10

    Violent variation of transit depths and an ingress-egress asymmetry of the transit light curve discovered in KIC 12557548 have been interpreted as evidence of a catastrophic evaporation of atmosphere with dust ( M-dot {sub p}?>1 M{sub ?} Gyr{sup 1}) from a close-in small planet. To explore what drives the anomalous atmospheric escape, we perform time-series analysis of the transit depth variation of Kepler archival data for ?3.5 yr. We find a ?30% periodic variation of the transit depth with P {sub 1} = 22.83 0.21 days, which is within the error of the rotation period of the host star estimated using the light curve modulation, P {sub rot} = 22.91 0.24 days. We interpret the results as evidence that the atmospheric escape of KIC 12557548b correlates with stellar activity. We consider possible scenarios that account for both the mass loss rate and the correlation with stellar activity. X-ray and ultraviolet (XUV)-driven evaporation is possible if one accepts a relatively high XUV flux and a high efficiency for converting the input energy to the kinetic energy of the atmosphere. Star-planet magnetic interaction is another possible scenario, though huge uncertainty remains for the mass loss rate.

  4. LINKING Lyα AND LOW-IONIZATION TRANSITIONS AT LOW OPTICAL DEPTH

    SciTech Connect (OSTI)

    Jaskot, A. E.; Oey, M. S.

    2014-08-20

    We suggest that low optical depth in the Lyman continuum (LyC) may relate the Lyα emission, C II and Si II absorption, and C II* and Si II* emission seen in high-redshift galaxies. We base this analysis on Hubble Space Telescope Cosmic Origins Spectrograph spectra of four Green Pea (GP) galaxies, which may be analogs of z > 2 Lyα emitters (LAEs). In the two GPs with the strongest Lyα emission, the Lyα line profiles show reduced signs of resonant scattering. Instead, the Lyα profiles resemble the Hα line profiles of evolved star ejecta, suggesting that the Lyα emission originates from a low column density and similar outflow geometry. The weak C II absorption and presence of non-resonant C II* emission in these GPs support this interpretation and imply a low LyC optical depth along the line of sight. In two additional GPs, weak Lyα emission and strong C II absorption suggest a higher optical depth. These two GPs differ in their Lyα profile shapes and C II* emission strengths, however, indicating different inclinations of the outflows to our line of sight. With these four GPs as examples, we explain the observed trends linking Lyα, C II, and C II* in stacked LAE spectra, in the context of optical depth and geometric effects. Specifically, in some galaxies with strong Lyα emission, a low LyC optical depth may allow Lyα to escape with reduced scattering. Furthermore, C II absorption, C II* emission, and Lyα profile shape can reveal the optical depth, constrain the orientation of neutral outflows in LAEs, and identify candidate LyC emitters.

  5. Structural transition and orbital glass physics in near-itinerant...

    Office of Scientific and Technical Information (OSTI)

    Title: Structural transition and orbital glass physics in ... which can be driven metallic with moderate applied pressure. ... Type: Accepted Manuscript Journal Name: Physical Review B ...

  6. Energy level structure and transition probabilities in the spectra...

    Office of Scientific and Technical Information (OSTI)

    Energy level structure and transition probabilities in the spectra of the trivalent lanthanides in LaFsub 3. Tables, diagrams Citation Details In-Document Search Title: Energy ...

  7. 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

  8. Probing the surface structure of divalent transition metals using...

    Office of Scientific and Technical Information (OSTI)

    Title: Probing the surface structure of divalent transition metals using surface specific solid-state NMR spectroscopy Authors: Mason, H E ; Harley, S J ; Maxwell, R S ; Carroll, S ...

  9. Uniaxial pressure effect on structural and magnetic phase transitions...

    Office of Scientific and Technical Information (OSTI)

    and its comparison with as-grown and annealed BaFe 2 As 2 Prev Next Title: Uniaxial pressure effect on structural and magnetic phase transitions in NaFeAs and its ...

  10. Characterization of structural response to hypersonic boundary-layer transition

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

    Riley, Zachary B.; Deshmukh, Rohit; Miller, Brent A.; McNamara, Jack J.; Casper, Katya M.

    2016-05-24

    The inherent relationship between boundary-layer stability, aerodynamic heating, and surface conditions makes the potential for interaction between the structural response and boundary-layer transition an important and challenging area of study in high-speed flows. This paper phenomenologically explores this interaction using a fundamental two-dimensional aerothermoelastic model under the assumption of an aluminum panel with simple supports. Specifically, an existing model is extended to examine the impact of transition onset location, transition length, and transitional overshoot in heat flux and fluctuating pressure on the structural response of surface panels. Transitional flow conditions are found to yield significantly increased thermal gradients, and theymore » can result in higher maximum panel temperatures compared to turbulent flow. Results indicate that overshoot in heat flux and fluctuating pressure reduces the flutter onset time and increases the strain energy accumulated in the panel. Furthermore, overshoot occurring near the midchord can yield average temperatures and peak displacements exceeding those experienced by the panel subject to turbulent flow. Lastly, these results suggest that fully turbulent flow does not always conservatively predict the thermo-structural response of surface panels.« less

  11. Structural Phase Transition in AuZn Alloys

    SciTech Connect (OSTI)

    Winn,B.L.; Shapiro, S.M.; Lashley, J.C.; Opeil, C.; Ratcliff, W.

    2009-05-03

    AuxZn1-x alloys undergo a shape memory martensitic transformation whose temperature and nature (continuous or discontinuous) is strongly composition dependent. Neutron diffraction experiments were performed on single crystals of x=50 and 52 to explore the structural changes occurring at the transition temperature. A transverse modulation with wavevector q0=(1/3,1/3,0) develops below the transition temperature, with no observable change in lattice parameter. However, the Bragg peak width shows a broadening suggesting an unresolved rhombohedral distortion similar to what has been observed in NiTi-Fe alloys.

  12. Structure transitions induced by the Hall term in homogeneous and isotropic magnetohydrodynamic turbulence

    SciTech Connect (OSTI)

    Miura, H., E-mail: miura.hideaki@nifs.ac.jp [Department of Helical Plasma Research, National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Araki, K. [Faculty of Engineering, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005 (Japan)

    2014-07-15

    Hall effects on local structures in homogeneous, isotropic, and incompressible magnetohydrodynamic turbulence are studied numerically. The transition of vortices from sheet-like to tubular structures induced by the Hall term is found, while the kinetic energy spectrum does not distinguish the two types of structures. It is shown by the use of the sharp low-pass filter that the transition occurs not only in the scales smaller than the ion skin depth but also in a larger scale. The transition is related with the forward energy transfer in the spectral space. Analyses by the use of the sharp low-pass filter show that the nonlinear energy transfer associated with the Hall term is dominated by the forward transfer and relatively local in the wave number space. A projection of the simulation data to a Smagorinsky-type sub-grid-scale model shows that the high wave number component of the Hall term may possibly be replaced by the model effectively.

  13. Light and phospholipid driven structural transitions in nematic microdroplets

    SciTech Connect (OSTI)

    Dubtsov, A. V., E-mail: alexanderdubtsov@gmail.com; Pasechnik, S. V.; Shmeliova, D. V. [Moscow State University of Instrument Engineering and Computer Science, Stromynka 20, Moscow 107996 (Russian Federation); Kralj, Samo [Condensed Matter Physics Department, Joef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); FNM, University of Maribor, Koroska 160, 2000 Maribor (Slovenia)

    2014-10-13

    We studied the UV-irradiation and phospholipid driven bipolar-radial structural transitions within azoxybenzene nematic liquid crystal (LC) droplets dispersed in water. It was found that the UV-irradiation induced trans-cis isomerisation of LC molecules could enable structural transitions into radial-type configurations at a critical UV-irradiation time t{sub c}. In particular, we show that under appropriate conditions, a value of t{sub c} could sensitively fingerprint the concentration of phospholipid molecules present in LC-water dispersions. This demonstrated proof-of-principle mechanism could be exploited for development of sensitive detectors for specific nanoparticles (NPs), where value of t{sub c} reveals concentration of NPs.

  14. Depth-resolved confocal micro-Raman spectroscopy for characterizing GaN-based light emitting diode structures

    SciTech Connect (OSTI)

    Chen, Wei-Liang; Lee, Yu-Yang; Chang, Yu-Ming; Chang, Chiao-Yun; Huang, Huei-Min; Lu, Tien-Chang

    2013-11-15

    In this work, we demonstrate that depth-resolved confocal micro-Raman spectroscopy can be used to characterize the active layer of GaN-based LEDs. By taking the depth compression effect due to refraction index mismatch into account, the axial profiles of Raman peak intensities from the GaN capping layer toward the sapphire substrate can correctly match the LED structural dimension and allow the identification of unique Raman feature originated from the 0.3 μm thick active layer of the studied LED. The strain variation in different sample depths can also be quantified by measuring the Raman shift of GaN A{sub 1}(LO) and E{sub 2}(high) phonon peaks. The capability of identifying the phonon structure of buried LED active layer and depth-resolving the strain distribution of LED structure makes this technique a potential optical and remote tool for in operando investigation of the electronic and structural properties of nitride-based LEDs.

  15. Structural phase transitions in BaPrO{sub 3}

    SciTech Connect (OSTI)

    Saines, Paul J.; Kennedy, Brendan J. Smith, Ronald I.

    2009-04-02

    The crystal structures adopted by BaPrO{sub 3} at and above ambient temperature have been examined using a combination of synchrotron X-ray and neutron diffraction. BaPrO{sub 3} has been established to undergo a series of phase transitions from Pbnmorthorhombic{yields}Ibmmorthorhombic{yields}R3-bar crhombohedral{yields}Pm3-barm cubic. BaPrO{sub 3} is the second A{sup 2+}B{sup 4+}O{sub 3} perovskite found to adopt rhombohedral symmetry in preference to the I4/mcm tetragonal structure. Analysis of the octahedral tilting through the rhombohedral to cubic phase transition indicates that this transformation is continuous and tricritical in nature. The tricritical behaviour of this transition is likely to be a result of the competition between tetragonal and rhombohedral structures to be the preferred phase, with the rhombohedral symmetry adopted by BaPrO{sub 3} being stabilised by the unusually large B-site cation.

  16. A Reversible Structural Phase Transition in ZnV2O6 at High Pressures...

    Office of Scientific and Technical Information (OSTI)

    A Reversible Structural Phase Transition in ZnV2O6 at High Pressures Citation Details In-Document Search Title: A Reversible Structural Phase Transition in ZnV2O6 at High Pressures ...

  17. Giant Controllable Magnetization Changes Induced by Structural Phase Transitions in a Metamagnetic Artificial Multiferroic

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

    Bennett, S. P.; Wong, A. T.; Glavic, A.; Herklotz, A.; Urban, C.; Valmianski, I.; Biegalski, M. D.; Christen, H. M.; Ward, T. Z.; Lauter, V.

    2016-03-04

    We realize that a controllable metamagnetic transition from AFM to FM ordering would open the door to a plethora of new spintronics based devices that, rather than reorienting spins in a ferromagnet, harness direct control of a materials intrinsic magnetic ordering. In this study FeRh films with drastically reduced transition temperatures and a large magneto-thermal hysteresis were produced for magnetocaloric and spintronics applications. Remarkably, giant controllable magnetization changes (measured to be as high has ~25%) are realized and by manipulating the strain transfer from the external lattice when subjected to two structural phase transitions of BaTiO3 (001) single crystal substrate.more » These magnetization changes are the largest seen to date to be controllably induced in the FeRh system. Using polarized neutron reflectometry we reveal how just a slight in plane surface strain change at ~290C results in a massive magnetic transformation in the bottom half of the film clearly demonstrating a strong lattice-spin coupling in FeRh. By means of these substrate induced strain changes we show a way to reproducibly explore the effects of temperature and strain on the relative stabilities of the FM and AFM phases in multi-domain metamagnetic systems. In our study also demonstrates for the first time the depth dependent nature of a controllable magnetic order using strain in an artificial multiferroic heterostructure.« less

  18. Detection of in-depth helical spin structures by planar Hall effect

    SciTech Connect (OSTI)

    Basaran, Ali C. Guénon, S.; Schuller, Ivan K.; Morales, R.

    2015-06-22

    We developed a method to determine the magnetic helicity and to study reversal mechanisms in exchange biased nanostructures using Planar Hall Effect (PHE). As a test case, we use an in-depth helical spin configuration that occurs during magnetization reversal in exchange coupled Ni/FeF{sub 2} heterostructures. We show the way to induce and determine the sign of the helicity from PHE measurements on a lithographically patterned cross. The helicity sign can be controlled by the angle between the externally applied magnetic field and a well-defined unidirectional anisotropy axis. Furthermore, the PHE signal reveals complex reversal features due to small deviations of the local unidirectional anisotropy axes from the crystallographic easy axis. The simulations using an incomplete domain wall model are in excellent agreement with the experimental data. These studies show that helical spin formations in nanomagnetic systems can be studied using laboratory-based magnetotransport.

  19. (Electronic structure and reactivities of transition metal clusters)

    SciTech Connect (OSTI)

    Not Available

    1992-01-01

    The following are reported: theoretical calculations (configuration interaction, relativistic effective core potentials, polyatomics, CASSCF); proposed theoretical studies (clusters of Cu, Ag, Au, Ni, Pt, Pd, Rh, Ir, Os, Ru; transition metal cluster ions; transition metal carbide clusters; bimetallic mixed transition metal clusters); reactivity studies on transition metal clusters (reactivity with H{sub 2}, C{sub 2}H{sub 4}, hydrocarbons; NO and CO chemisorption on surfaces). Computer facilities and codes to be used, are described. 192 refs, 13 figs.

  20. Accurate Band-Structure Calculations for the 3d Transition Metal Oxides

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

    has developed a method to calculate accurate band structures and bandgap energies for 3d transition metal oxides using an augmented GW formalism. Significance and Impact This approach provides a computationally viable route for high-throughput prediction of band structures and optical properties in transition metal compounds. Accurate Band-Structure Calculations for the 3d Transition Metal Oxides S. Lany, Phys. Rev. B 87, 085112 (2013). Density of states (DOS) and absorption spectrum, shown for

    1. Structural phase transitions and topological defects in ion Coulomb crystals

      SciTech Connect (OSTI)

      Partner, Heather L.; Nigmatullin, Ramil; Burgermeister, Tobias; Keller, Jonas; Pyka, Karsten; Plenio, Martin B.; Retzker, Alex; Zurek, Wojciech Hubert; del Campo, Adolfo; Mehlstaubler, Tanja E.

      2014-11-19

      We use laser-cooled ion Coulomb crystals in the well-controlled environment of a harmonic radiofrequency ion trap to investigate phase transitions and defect formation. Topological defects in ion Coulomb crystals (kinks) have been recently proposed for studies of nonlinear physics with solitons and as carriers of quantum information. Defects form when a symmetry breaking phase transition is crossed non-adiabatically. For a second order phase transition, the Kibble-Zurek mechanism predicts that the formation of these defects follows a power law scaling in the rate of the transition. We demonstrate a scaling of defect density and describe kink dynamics and stability. We further discuss the implementation of mass defects and electric fields as first steps toward controlled kink preparation and manipulation.

    2. Pressure-Induced Structural Phase Transition in CeNi: X-ray and...

      Office of Scientific and Technical Information (OSTI)

      Pressure-Induced Structural Phase Transition in CeNi: X-ray and Neutron Scattering Studies and First-Principles Calculations Citation Details In-Document Search Title: ...

    3. Depth-dependent Vertical-to-Horizontal (V/H) Ratios of Free-Field Ground Motion Response Spectra for Deeply Embedded Nuclear Structures

      SciTech Connect (OSTI)

      Wei X.; Braverman J.; Miranda, M.; Rosario, M.E.; Costantino, C.J.

      2015-02-25

      This report documents the results of a study to determine the depth-dependent V/H ratios of ground motion response spectra in the free field. The V/H ratios reported herein were developed from a worldwide database of surface and downhole acceleration recordings obtained from 45 vertical array stations. This database was specifically compiled for this project, and includes information from a diversity of active tectonic regions (California, Alaska, Taiwan, Japan), site conditions (rock to soft soil), ground motion intensity levels (PGAs between 0.01 g and 0.50 g), magnitudes (between ML 2.78 and JMA 8.1), epicentral distances (between 3.2 km and 812 km), and source depths (between 1.2 km and 112 km), as well as sensors at surface and at a wide range of depths relevant to the project. To study the significance of the depth effect, V/H ratios from all the records were sorted into a number of depth bins relevant to the project, and statistics (average, standard deviation, coefficient of variation, 16th, 50th, and 84th percentiles) of the V/H ratios within each bin were computed. Similar analyses were repeated, controlling for different site conditions, ground motion intensity levels, array locations, and source depths, to study their relative effect on the V/H ratios. Our findings confirm the importance of the depth effect on the V/H ratios. The research findings in this report can be used to provide guidance on the significance of the depth effect, and the extent to which this effect should be considered in the seismic design of deeply embedded SMR structures and NPP structures in general.

    4. Seismic Velocity Structure and Depth-Dependence of Anisotropy in the Red Sea and Arabian Shield from Surface Wave Analysis

      SciTech Connect (OSTI)

      Hansen, S; Gaherty, J; Schwartz, S; Rodgers, A; Al-Amri, A

      2007-07-25

      We investigate the lithospheric and upper mantle structure as well as the depth-dependence of anisotropy along the Red Sea and beneath the Arabian Peninsula using receiver function constraints and phase velocities of surface waves traversing two transects of stations from the Saudi Arabian National Digital Seismic Network. Frequency-dependent phase delays of fundamental-mode Love and Rayleigh waves, measured using a cross-correlation procedure, require very slow shear velocities and the presence of anisotropy throughout the upper mantle. Linearized inversion of these data produce path-averaged 1D radially anisotropic models with about 4% anisotropy in the lithosphere, increasing to about 4.8% anisotropy across the lithosphere-asthenosphere boundary (LAB). Models with reasonable crustal velocities in which the mantle lithosphere is isotropic cannot satisfy the data. The lithospheric lid, which ranges in thickness from about 70 km near the Red Sea coast to about 90 km beneath the Arabian Shield, is underlain by a pronounced low-velocity zone with shear velocities as low as 4.1 km/s. Forward models, which are constructed from previously determined shear-wave splitting estimates, can reconcile surface and body wave observations of anisotropy. The low shear velocity values are similar to many other continental rift and oceanic ridge environments. These low velocities combined with the sharp velocity contrast across the LAB may indicate the presence of partial melt beneath Arabia. The anisotropic signature primarily reflects a combination of plate- and density-driven flow associated with active rifting processes in the Red Sea.

    5. The structural origin of the hard-sphere glass transition in granular packing

      SciTech Connect (OSTI)

      Xia, Chengjie; Li, Jindong; Cao, Yixin; Kou, Binquan; Xiao, Xianghui; Fezzaa, Kamel; Xiao, Tiqiao; Wang, Yujie

      2015-09-28

      Glass transition is accompanied by a rapid growth of the structural relaxation time and a concomitant decrease of configurational entropy. It remains unclear whether the transition has a thermodynamic origin, and whether the dynamic arrest is associated with the growth of a certain static order. Using granular packing as a model hard-sphere glass, we show the glass transition as a thermodynamic phase transition with a ‘hidden’ polytetrahedral order. This polytetrahedral order is spatially correlated with the slow dynamics. It is geometrically frustrated and has a peculiar fractal dimension. Additionally, as the packing fraction increases, its growth follows an entropy-driven nucleation process, similar to that of the random first-order transition theory. In conclusion, our study essentially identifies a long-sought-after structural glass order in hard-sphere glasses.

    6. The structural origin of the hard-sphere glass transition in granular packing

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

      Xia, Chengjie; Li, Jindong; Cao, Yixin; Kou, Binquan; Xiao, Xianghui; Fezzaa, Kamel; Xiao, Tiqiao; Wang, Yujie

      2015-09-28

      Glass transition is accompanied by a rapid growth of the structural relaxation time and a concomitant decrease of configurational entropy. It remains unclear whether the transition has a thermodynamic origin, and whether the dynamic arrest is associated with the growth of a certain static order. Using granular packing as a model hard-sphere glass, we show the glass transition as a thermodynamic phase transition with a ‘hidden’ polytetrahedral order. This polytetrahedral order is spatially correlated with the slow dynamics. It is geometrically frustrated and has a peculiar fractal dimension. Additionally, as the packing fraction increases, its growth follows an entropy-driven nucleationmore » process, similar to that of the random first-order transition theory. In conclusion, our study essentially identifies a long-sought-after structural glass order in hard-sphere glasses.« less

    7. Reciprocal space XRD mapping with varied incident angle as a probe of structure variation within surface depth

      SciTech Connect (OSTI)

      Yang, Qiguang; Williams, Frances; Zhao, Xin; Reece, Charles E.; Krishnan, Mahadevan

      2013-09-01

      In this study, we used a differential-depth X-Ray diffraction Reciprocal Spacing Mapping (XRD RSM) technique to investigate the crystal quality of a variety of SRF-relevant Nb film and bulk materials. By choosing different X-ray probing depths, the RSM study successfully revealed evolution the of materials? microstructure after different materials processes, such as energetic condensation or surface polishing. The RSM data clearly measured the materials? crystal quality at different thickness. Through a novel differential-depth RSM technique, this study found: I. for a heteroepitaxy Nb film Nb(100)/MgO(100), the film thickening process, via a cathodic arc-discharge Nb ion deposition, created a near-perfect single crystal Nb on the surface?s top-layer; II. for a mechanically polished single-crystal bulk Nb material, the microstructure on the top surface layer is more disordered than that in-grain.

    8. Structural and magnetic phase transitions near optimal superconductivity in BaFe2(As1-xPx)2

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

      Hu, Ding; Lu, Xingye; Zhang, Wenliang; Luo, Huiqian; Li, Shiliang; Wang, Peipei; Chen, Genfu; Han, Fei; Banjara, Shree R.; Sapkota, A.; et al

      2015-04-17

      In this study, we use nuclear magnetic resonance (NMR), high-resolution x-ray and neutron scattering to study structural and magnetic phase transitions in phosphorus-doped BaFe2(As1-xPx)2. Thus, previous transport, NMR, specific heat, and magnetic penetration depth measurements have provided compelling evidence for the presence of a quantum critical point (QCP) near optimal superconductivity at x = 0.3. However, we show that the tetragonal-to-orthorhombic structural (Ts) and paramagnetic to antiferromagnetic (AF, TN) transitions in BaFe2(As1-xPx)2 are always coupled and approach to TN ≈ Ts ≥ Tc (≈ 29 K) for x = 0.29 before vanishing abruptly for x ≥ 0.3. These results suggestmore » that AF order in BaFe2(As1-xPx)2 disappears in a weakly first order fashion near optimal superconductivity, much like the electron-doped iron pnictides with an avoided QCP.« less

    9. 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.

    10. 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

    11. 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

    12. Structural Phase Transitions and Water Dynamics in Uranyl Fluoride Hydrates

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

      Miskowiec, Andrew J.; Kirkegaard, Marie C.; Huq, Ashfia; Mamontov, Eugene; Herwig, Kenneth W.; Trowbridge, Lee D.; Rondinone, Adam Justin; Anderson, Brian B.

      2015-11-17

      We report a novel production method for uranium oxy uoride [(UO2)7F14(H2O)7] 4H2O, referred to as structure D. Structure D is produced as a product of hydrating anhydrous uranyl uoride, UO2F2, through the gas phase at ambient temperatures fol- lowed by desiccation by equilibration with a dry environment. We follow the structure of [(UO2)7F14(H2O)7] 4H2O through an intermediate, liquid-like phase, wherein the coordination number of the uranyl ion is reduced to 5 (from 6 in the anhydrous struc- ture), and a water molecule binds as an equatorial ligand to the uranyl ion. Quasielas- tic neutron scattering results compare well with previousmore » measurements of mineral hydrates. The two groups of structurally distinct water molecules in D perform re- stricted motion on a length scale commensurate with the O{H bond (r = 0.92 A). The more tightly bound equatorial ligand waters rotate slower (Dr = 2.2 ps-1) than their hydrogen-bonded partners (Dr = 28.7 ps-1).« less

    13. Structural Phase Transitions and Water Dynamics in Uranyl Fluoride Hydrates

      SciTech Connect (OSTI)

      Miskowiec, Andrew J.; Kirkegaard, Marie C.; Huq, Ashfia; Mamontov, Eugene; Herwig, Kenneth W.; Trowbridge, Lee D.; Rondinone, Adam Justin; Anderson, Brian B.

      2015-11-17

      We report a novel production method for uranium oxy uoride [(UO2)7F14(H2O)7] 4H2O, referred to as structure D. Structure D is produced as a product of hydrating anhydrous uranyl uoride, UO2F2, through the gas phase at ambient temperatures fol- lowed by desiccation by equilibration with a dry environment. We follow the structure of [(UO2)7F14(H2O)7] 4H2O through an intermediate, liquid-like phase, wherein the coordination number of the uranyl ion is reduced to 5 (from 6 in the anhydrous struc- ture), and a water molecule binds as an equatorial ligand to the uranyl ion. Quasielas- tic neutron scattering results compare well with previous measurements of mineral hydrates. The two groups of structurally distinct water molecules in D perform re- stricted motion on a length scale commensurate with the O{H bond (r = 0.92 A). The more tightly bound equatorial ligand waters rotate slower (Dr = 2.2 ps-1) than their hydrogen-bonded partners (Dr = 28.7 ps-1).

    14. Global phenomenology of mean field structure and phase transitional behavior in nuclei

      SciTech Connect (OSTI)

      Zamfir, N.V. ||; Casten, R.F.; Brenner, D.S.

      1994-03-01

      Correlation schemes of nuclear properties provide a powerful organizing principle for nuclear phenomenology. Mean field observables can be systematized in the framework of Valence Correlation Schemes. Direct Correlations Schemes provide new signatures to identify particular structure. The correlations of yrast energies give a new tripartite global characterization of the evolution of nuclear structure. The linking regions where the major structural changes occur can be interpreted in terms of critical phase transitions.

    15. Crystal structures and phase transitions in Ba{sub 2}HoTaO{sub 6}

      SciTech Connect (OSTI)

      Kennedy, Brendan J. Saines, Paul J.; Kubota, Yoshiki; Minakata, Chiharu; Hano, Hiroko; Kato, Kenichi; Takata, Masaki

      2007-11-06

      The structure of the cation-ordered double perovskite Ba{sub 2}HoTaO{sub 6} was examined using synchrotron X-ray powder diffraction at fine temperature intervals over the range of 90-300 K. Ba{sub 2}HoTaO{sub 6} has a cubic structure in space group Fm3-barm at room temperature. A proper ferroelastic phase transition to I4/m tetragonal symmetry occurs near approximately 260 K. Analysis of the spontaneous tetragonal strain versus temperature indicated that the phase transition is second order in nature.

    16. Crystal structure and phase transition mechanisms in CsFe{sub 2}F{sub 6}

      SciTech Connect (OSTI)

      Molokeev, M.S.; Bogdanov, E.V.; Misyul, S.V.; Tressaud, A.; Flerov, I.N.

      2013-04-15

      For the first time, structural phase transitions induced by the temperature were found in A{sub x}M{sub x}{sup II}M{sub (1?x)}{sup III}F{sub 3} fluorides with the defect pyrochlore structure (Fd3{sup }m, Z=8). The room temperature structure of CsFe{sub 2}F{sub 6} was determined using X-ray powder diffraction technique. This phase was found to be ordered with the Pnma space group. The study of the temperature stability of orthorhombic structure by differential scanning calorimeter between 100 K and 700 K has shown a succession of phase transitions. The Pnma (Z=4)?Imma (Z=4)?I4{sub 1}/amd (Z=4)?Fd3{sup }m (Z=8) structural sequence was proposed to occur within a rather narrow temperature range 500560 K. The mechanism of structural transition has been mainly associated with the rotation of (MF{sub 6}) octahedra and small displacements of some Fe atoms. This assumption is in good agreement with the low experimental entropy value, which is characteristic for displacive transformations. - Graphical abstract: Mechanism of phase transition between the HT cubic form of CsFe{sub 2}F{sub 6} at 573 K (left) and the room temperature orthorhombic form at 298 K (right). The grey rectangles are clusters of five FeF{sub 6} octahedra. Highlights: ? Structural transition found for the first time in CsFe{sub 2}F{sub 6} with defect pyrochlore type. ? Fe{sup II} and Fe{sup III} atoms are ordered in room temperature Pnma form of CsFe{sub 2}F{sub 6}. ? Pnma(Z=4)?Imma(Z=4)?I4{sub 1}/amd(Z=4)?Fd-3m(Z=8) transition sequence is proposed. ? Structural transition due to rotation of MF{sub 6} groups+small displacements of Fe atoms. ? The low value of the entropy is in agreement with a displacive-type transition.

    17. 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

    18. Structural Flexibility and Alloying in Ultrathin Transition-Metal Chalcogenide Nanowires

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

      Lin, Junhao; Zhang, Yuyang; Zhou, Wu; Pantelides, Sokrates T.

      2016-01-18

      Metallic transition-metal chalcogenide (TMC) nanowires are an important building block for 2D electronics that may be fabricated within semiconducting transition-metal dichalcogenide (TMDC) monolayers. Tuning the geometric structure and electronic properties of such nanowires is a promising way to pattern diverse functional channels for wiring multiple units inside a 2D electronic circuit. Nevertheless, few experimental investigations have been reported exploring the structural and compositional tunability of these nanowires, due to difficulties in manipulating the structure and chemical composition of an individual nanowire. Here, using a combination of scanning transmission electron microscopy (STEM) and density functional theory (DFT), we report that TMCmore » nanowires have substantial intrinsic structural flexibility and their chemical composition can be manipulated.« less

    19. Rare-Earth Transition-Metal Intermetallics: Structure-bonding-Property Relationships

      SciTech Connect (OSTI)

      Mi-Kyung Han

      2006-05-01

      Our explorations of rare-earth, transition metal intermetallics have resulted in the synthesis and characterization, and electronic structure investigation, as well as understanding the structure-bonding-property relationships. Our work has presented the following results: (1) Understanding the relationship between compositions and properties in LaFe{sub 13-x}Si{sub x} system: A detailed structural and theoretical investigation provided the understanding of the role of a third element on stabilizing the structure and controlling the transformation of cubic NaZn{sub 13}-type structures to the tetragonal derivative, as well as the relationship between the structures and properties. (2) Synthesis of new ternary rare-earth iron silicides RE{sub 2-x}Fe{sub 4}Si{sub 14-y} and proposed superstructure: This compound offers complex structural challenges such as fractional occupancies and their ordering in superstructure. (3) Electronic structure calculation of FeSi{sub 2}: This shows that the metal-semiconductor phase transition depends on the structure. The mechanism of band gap opening is described in terms of bonding and structural distortion. This result shows that the electronic structure calculations are an essential tool for understanding the relationship between structure and chemical bonding in these compounds. (4) Synthesis of new ternary rare-earth Zinc aluminides Tb{sub 3}Zn{sub 3.6}Al{sub 7.4}: Partially ordered structure of Tb{sub 3}Zn{sub 3.6}Al{sub 7.4} compound provides new insights into the formation, composition and structure of rare-earth transition-metal intermetallics. Electronic structure calculations attribute the observed composition to optimizing metal-metal bonding in the electronegative (Zn, Al) framework, while the specific ordering is strongly influenced by specific orbital interactions. (5) Synthesis of new structure type of Zn{sub 39}(Cr{sub x}Al{sub 1-x}){sub 81}: These layered structures are similar to icosahedral Mn-Al quasicrystalline

    20. Rare-earth transition-metal intermetallics: Structure-bonding-property relationships

      SciTech Connect (OSTI)

      Han, M.K.

      2006-05-06

      The explorations of rare-earth, transition metal intermetallics have resulted in the synthesis and characterization, and electronic structure investigation, as well as understanding the structure-bonding property relationships. The work has presented the following results: (1) Understanding the relationship between compositions and properties in LaFe{sub 13-x}Si{sub x} system: A detailed structural and theoretical investigation provided the understanding of the role of a third element on stabilizing the structure and controlling the transformation of cubic NaZn{sub 13}-type structures to the tetragonal derivative, as well as the relationship between the structures and properties. (2) Synthesis of new ternary rare-earth iron silicides Re{sub 2-x}Fe{sub 4}Si{sub 14-y} and proposed superstructure: This compound offers complex structural challenges such as fractional occupancies and their ordering in superstructure. (3) Electronic structure calculation of FeSi{sub 2}: This shows that the metal-semiconductor phase transition depends on the structure. The mechanism of band gap opening is described in terms of bonding and structural distortion. This result shows that the electronic structure calculations are an essential tool for understanding the relationship between structure and chemical bonding in these compounds. (4) Synthesis of new ternary rare-earth Zinc aluminides Tb{sub 3}Zn{sub 3.6}Al{sub 7.4}: Partially ordered structure of Tb{sub 3}Zn{sub 3.6}Al{sub 7.4} compound provides new insights into the formation, composition and structure of rare-earth transition-metal intermetallics. Electronic structure calculations attribute the observed composition to optimizing metal-metal bonding in the electronegative (Zn, Al) framework, while the specific ordering is strongly influenced by specific orbital interactions. (5) Synthesis of new structure type of Zn{sub 39}(Cr{sub x}Al{sub 1-x}){sub 81}: These layered structures are similar to icosahedral Mn-Al quasicrystalline

    1. Structural transition in rare earth doped zirconium oxide: A positron annihilation study

      SciTech Connect (OSTI)

      Chakraborty, Keka; Bisoi, Abhijit

      2012-11-15

      Graphical abstract: New microstructural analysis and phase transition of rare earth doped mixed oxide compounds such as: Sm{sub 2?x}Dy{sub x}Zr{sub 2}O{sub 7} (where x = 0.0 ? x ? 2.0) that are potentially useful as solid oxide fuels, ionic conductors, optoelectronic materials and most importantly as radiation resistant host for high level rad-waste disposal, structural transition in the system is reported through positron annihilation spectroscopy as there is an indication in the X-ray diffraction analysis. Highlights: ? Zirconium oxide material doped with rare earth ions. ? The method of positron annihilation spectroscopy suggests a phase transition in the system. ? The crystal structure transformation from pure pyrochlore to defect fluorite type of structure is shown by X-ray diffraction results. -- Abstract: A series of compounds with the general composition Sm{sub 2?x}Dy{sub x}Zr{sub 2}O{sub 7} (where 0 ? x ? 2.0) were synthesized by chemical route and characterized by powder X-ray diffraction (XRD) analysis. The rare earth ion namely Sm{sup +3} in the compound was gradually replaced with another smaller and heavier ion, Dy{sup +3} of the 4f series, there by resulting in orderdisorder structural transition, which has been studied by positron annihilation lifetime and Doppler broadening spectroscopy. This study reveals the subtle electronic micro environmental changes in the pyrochlore lattice (prevalent due to the oxygen vacancy in anti-site defect structure of the compound) toward its transformation to defect fluorite structure as found in Dy{sub 2}Zr{sub 2}O{sub 7}. A comparison of the changes perceived with PAS as compared to XRD analysis is critically assayed.

    2. Structural Transition of PETN-I to Ferroelastic Orthorhombic Phase PETN-III at Elevated Pressures

      SciTech Connect (OSTI)

      Tschauner,O.; Kiefer, B.; Lee, Y.; Pravica, M.; Nicol, M.; Kim, E.

      2007-01-01

      Using powder x-ray diffraction and first-principles calculations, we provide evidence for a structural transition of PETN-I below 6 GPa to an orthorhombic phase of space group P2{sub 1}2{sub 1}2. The transition can be rationalized as shear-stress induced and ferroelastic, which involves a slight static displacement of the molecules that breaks the fourfold symmetry of PETN-I. Previously reported changes in the optical spectra reflect a lifting of the twofold degeneracy of modes in tetragonal PETN-I. The observed transition is expected to induce soft shear compliances along specific directions in PETN crystallites that may relate to the observed dependence of detonation pressure on crystal orientation.

    3. Pressure induced metallization with absence of structural transition in layered molybdenum diselenide

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

      Zhao, Zhao; Zhang, Haijun; Yuan, Hongtao; Wang, Shibing; Lin, Yu; Zeng, Qiaoshi; Xu, Gang; Liu, Zhenxian; Solanki, G. K.; Patel, K. D.; et al

      2015-06-19

      Layered transition-metal dichalcogenides have emerged as exciting material systems with atomically thin geometries and unique electronic properties. Pressure is a powerful tool for continuously tuning their crystal and electronic structures away from the pristine states. Here, we systematically investigated the pressurized behavior of MoSe2 up to ~60 GPa using multiple experimental techniques and ab-initio calculations. MoSe2 evolves from an anisotropic two-dimensional layered network to a three-dimensional structure without a structural transition, which is a complete contrast to MoS2. The role of the chalcogenide anions in stabilizing different layered patterns is underscored by our layer sliding calculations. MoSe2 possesses highly tunablemore » transport properties under pressure, determined by the gradual narrowing of its band-gap followed by metallization. The continuous tuning of its electronic structure and band-gap in the range of visible light to infrared suggest possible energy-variable optoelectronics applications in pressurized transition-metal dichalcogenides.« less

    4. Structural and magnetic phase transitions in gadolinium under high pressures and low temperatures

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

      Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.; Vohra, Yogesh K.

      2014-11-07

      High pressure structural transition studies have been carried out on rare earth metal gadolinium in a diamond anvil cell at room temperature to 169 GPa. Gadolinium has been compressed to 38% of its initial volume at this pressure. With increasing pressure, a crystal structure sequence of hcp → Smtype→ dhcp → fcc → dfcc → monoclinic has been observed in our studies on gadolinium. The measured equation of state of gadolinium is presented to 169 GPa at ambient temperature. Magnetic ordering temperature of gadolinium has been studied using designer diamond anvils to a pressure of 25 GP and a temperaturemore » of 10 K. The magnetic ordering temperature has been determined from the four-point electrical resistivity measurements carried out on gadolinium. Furthermore, our experiments show that the magnetic transition temperature decreases with increasing pressure to 19 GPa and then increases when gadolinium is subjected to higher pressures.« less

    5. Structural and magnetic phase transitions in gadolinium under high pressures and low temperatures

      SciTech Connect (OSTI)

      Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.; Vohra, Yogesh K.

      2014-11-07

      High pressure structural transition studies have been carried out on rare earth metal gadolinium in a diamond anvil cell at room temperature to 169 GPa. Gadolinium has been compressed to 38% of its initial volume at this pressure. With increasing pressure, a crystal structure sequence of hcp → Smtype→ dhcp → fcc → dfcc → monoclinic has been observed in our studies on gadolinium. The measured equation of state of gadolinium is presented to 169 GPa at ambient temperature. Magnetic ordering temperature of gadolinium has been studied using designer diamond anvils to a pressure of 25 GP and a temperature of 10 K. The magnetic ordering temperature has been determined from the four-point electrical resistivity measurements carried out on gadolinium. Furthermore, our experiments show that the magnetic transition temperature decreases with increasing pressure to 19 GPa and then increases when gadolinium is subjected to higher pressures.

    6. Effect of surface attractive strength on structural transitions of a confined HP lattice protein

      SciTech Connect (OSTI)

      Pattanasiri, Busara; Li, Ying Wai; Wuest, Thomas; Landau, David P

      2015-01-01

      We investigate the influence of surface attractive strength on structural transitions of a hydrophobic-polar (HP) lattice protein confined in a slit formed by two parallel, attractive walls. We apply Wang-Landau sampling together with efficient Monte Carlo updates to estimate the density of states of the system. The conformational transitions, namely, the debridging process and hydrophobic core formation, can be identified by analyzing the specific heat together with several structural observables, such as the numbers of surface contacts, the number of hydrophobic pairs, and radii of gyration in different directions. As temperature decreases, we find that the occurrence of the debridging process is conditional depending on the surface attractive strength. This, in turn, affects the nature of the hydrophobic core formation that takes place at a lower temperature. We illustrate these observations with the aid of a HP protein chain with 48 monomers.

    7. Structure and magnetism of epitaxial rare-earth-transition-metal films

      SciTech Connect (OSTI)

      Fullerton, E.E.; Sowers, C.H.; Pearson, J.P.; Bader, S.D.

      1996-10-01

      Growth of epitaxial transition-metal superlattices; has proven essential in elucidating the role of crystal orientation and structure on magnetic properties such as giant magnetoresistance, interlayer coupling, and magnetic surface anisotropies. Extending these studies to the growth of epitaxial rare earth-transition metal (RE-TM) films and superlattices promises to play an equally important role in exploring and optimizing the properties of hard magnets. For instance, Skomski and Coey predict that a giant energy product (120 MG Oe) is possible in multilayer structures consisting of aligned hard-magnet layers exchanged coupled with soft-phase layers with high magnetization. Epitaxy provides one route to synthesizing such exchange-hardened magnets on controlled length scales. Epitaxial growth also allows the magnetic properties to be tailored by controlling the crystal orientation and the anisotropies of the magnetic layers and holds the possibility of stabilizing metastable phases. This paper describes the epitaxy and magnetic properties for several alloys.

    8. Excitonic transitions in highly efficient (GaIn)As/Ga(AsSb) type-II quantum-well structures

      SciTech Connect (OSTI)

      Gies, S.; Kruska, C.; Berger, C.; Hens, P.; Fuchs, C.; Rosemann, N. W.; Veletas, J.; Stolz, W.; Koch, S. W.; Heimbrodt, W.; Ruiz Perez, A.; Hader, J.; Moloney, J. V.

      2015-11-02

      The excitonic transitions of the type-II (GaIn)As/Ga(AsSb) gain medium of a “W”-laser structure are characterized experimentally by modulation spectroscopy and analyzed using microscopic quantum theory. On the basis of the very good agreement between the measured and calculated photoreflectivity, the type-I or type-II character of the observable excitonic transitions is identified. Whereas the energetically lowest three transitions exhibit type-II character, the subsequent energetically higher transitions possess type-I character with much stronger dipole moments. Despite the type-II character, the quantum-well structure exhibits a bright luminescence.

    9. Structural and magnetic phase transitions inEuTi1-xNbxO3

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

      Li, Ling; Morris, James R.; Koehler, Michael R.; Dun, Zhiling; Zhou, Haidong; Yan, Jiaqiang; Mandrus, David; Keppens, Veerle

      2015-07-30

      We have investigated the structural and magnetic phase transitions in EuTi1-xNbxO3 (0 ≤ x ≤ 0.3) with synchrotron powder x-ray diffraction, resonant ultrasound spectroscopy, and magnetization measurements. Upon Nb doping, the Pm3¯m ↔ I4/mcm structural transition shifts to higher temperatures and the room temperature lattice parameter increases while the magnitude of the octahedral tilting decreases. In addition, Nb substitution for Ti destabilizes the antiferromagnetic ground state of the parent compound and long-range ferromagnetic order is observed in the samples with x ≥ 0.1. The structural transition in pure and doped compounds is marked by a dramatic steplike softening of themore » elastic moduli near TS , which resembles that of SrTiO3 and can be adequately modeled using the Landau free energy model employing the same coupling between strain and octahedral tilting order parameter as previously used to model SrTiO3.« less

    10. Synthesis and structural, magnetic, thermal, and transport properties of several transition metal oxides and aresnides

      SciTech Connect (OSTI)

      Das, Supriyo

      2010-05-16

      Oxide compounds containing the transition metal vanadium (V) have attracted a lot of attention in the field of condensed matter physics owing to their exhibition of interesting properties including metal-insulator transitons, structural transitions, ferromagnetic and antiferromagnetic orderings, and heavy fermion behavior. Binary vanadium oxides V{sub n}O{sub 2n-1} where 2 {le} n {le} 9 have triclinic structures and exhibit metal-insulator and antiferromagnetic transitions. The only exception is V{sub 7}O{sub 13} which remains metallic down to 4 K. The ternary vanadium oxide LiV{sub 2}O{sub 4} has the normal spinel structure, is metallic, does not undergo magnetic ordering and exhibits heavy fermion behavior below 10 K. CaV{sub 2}O{sub 4} has an orthorhombic structure with the vanadium spins forming zigzag chains and has been suggested to be a model system to study the gapless chiral phase. These provide great motivation for further investigation of some known vanadium compounds as well as to explore new vanadium compounds in search of new physics. This thesis consists, in part, of experimental studies involving sample preparation and magnetic, transport, thermal, and x-ray measurements on some strongly correlated eletron systems containing the transition metal vanadium. The compounds studied are LiV{sub 2}O{sub 4}, YV{sub 4}O{sub 8}, and YbV{sub 4}O{sub 8}. The recent discovery of superconductivity in RFeAsO{sub 1-x}F{sub x} (R = La, Ce, Pr, Gd, Tb, Dy, Sm, and Nd), and AFe{sub 2}As{sub 2} (A = Ba, Sr, Ca, and Eu) doped with K, Na, or Cs at the A site with relatively high T{sub c} has sparked tremendous activities in the condensed matter physics community and a renewed interest in the area of superconductivity as occurred following the discovery of the layered cuprate high T{sub c} superconductors in 1986. To discover more superconductors with hopefully higher T{sub c}'s, it is extremely important to investigate compounds having crystal structures related to the

    11. Structural evolution of epitaxial SrCoOx films near topotactic phase transition

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

      Jeen, Hyoung Jeen; Lee, Ho Nyung

      2015-12-18

      Control of oxygen stoichiometry in complex oxides via topotactic phase transition is an interesting avenue to not only modifying the physical properties, but utilizing in many energy technologies, such as energy storage and catalysts. However, detailed structural evolution in the close proximity of the topotactic phase transition in multivalent oxides has not been much studied. In this work, we used strontium cobaltites (SrCoOx) epitaxially grown by pulsed laser epitaxy (PLE) as a model system to study the oxidation-driven evolution of the structure, electronic, and magnetic properties. We grew coherently strained SrCoO2.5thin films and performed post-annealing at various temperatures for topotacticmore » conversion into the perovskite phase (SrCoO3-δ). We clearly observed significant changes in electronic transport, magnetism, and microstructure near the critical temperature for the topotactic transformation from the brownmillerite to the perovskite phase. Furthermore, the overall crystallinity was well maintained without much structural degradation, indicating that topotactic phase control can be a useful tool to control the physical properties repeatedly via redox reactions.« less

    12. ARM - Measurement - Snow depth

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

      Send Measurement : Snow depth Snow depth measured at the surface Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the...

    13. Structural transition and amorphization in compressed α - Sb 2 O 3

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

      Zhao, Zhao; Zeng, Qiaoshi; Zhang, Haijun; Wang, Shibing; Hirai, Shigeto; Zeng, Zhidan; Mao, Wendy L.

      2015-05-27

      Sb₂O₃-based materials are of broad interest in materials science and industry. High-pressure study using diamond anvil cells shows promise in obtaining new crystal and electronic structures different from their pristine states. Here, we conducted in situ angle dispersive synchrotron x-ray-diffraction and Raman spectroscopy experiments on α-Sb₂O₃ up to 50 GPa with neon as the pressure transmitting medium. A first-order structural transition was observed in between 15 and 20 GPa, where the cubic phase I gradually transformed into a layered tetragonal phase II through structural distortion and symmetry breaking. To explain the dramatic changes in sample color and transparency, we performedmore » first-principles calculations to track the evolution of its density of states and electronic structure under pressure. At higher pressure, a sluggish amorphization was observed. Our results highlight the structural connections among the sesquioxides, where the lone electron pair plays an important role in determining the local structures.« less

    14. Crustal structure beneath two seismic stations in the Sunda-Banda arc transition zone derived from receiver function analysis

      SciTech Connect (OSTI)

      Syuhada; Hananto, Nugroho D.; Handayani, Lina; Puspito, Nanang T; Yudistira, Tedi; Anggono, Titi

      2015-04-24

      We analyzed receiver functions to estimate the crustal thickness and velocity structure beneath two stations of Geofon (GE) network in the Sunda-Banda arc transition zone. The stations are located in two different tectonic regimes: Sumbawa Island (station PLAI) and Timor Island (station SOEI) representing the oceanic and continental characters, respectively. We analyzed teleseismic events of 80 earthquakes to calculate the receiver functions using the time-domain iterative deconvolution technique. We employed 2D grid search (H-κ) algorithm based on the Moho interaction phases to estimate crustal thickness and Vp/Vs ratio. We also derived the S-wave velocity variation with depth beneath both stations by inverting the receiver functions. We obtained that beneath station PLAI the crustal thickness is about 27.8 km with Vp/Vs ratio 2.01. As station SOEI is covered by very thick low-velocity sediment causing unstable solution for the inversion, we modified the initial velocity model by adding the sediment thickness estimated using high frequency content of receiver functions in H-κ stacking process. We obtained the crustal thickness is about 37 km with VP/Vs ratio 2.2 beneath station SOEI. We suggest that the high Vp/Vs in station PLAI may indicate the presence of fluid ascending from the subducted plate to the volcanic arc, whereas the high Vp/Vs in station SOEI could be due to the presence of sediment and rich mafic composition in the upper crust and possibly related to the serpentinization process in the lower crust. We also suggest that the difference in velocity models and crustal thicknesses between stations PLAI and SOEI are consistent with their contrasting tectonic environments.

    15. Structural transition and orbital glass physics in near-itinerant CoV2O4

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

      Reig-i-Plessis, D.; Casavant, D.; Garlea, Vasile O.; Aczel, Adam A.; Feygenson, Mikhail; Neuefeind, Joerg C.; Zhou, H. D.; Nagler, Stephen E.; MacDougall, Gregory J.

      2016-01-25

      In this study, the ferrimagnetic spinel CoV2O4 has been a topic of intense recent interest, both as a frustrated insulator with unquenched orbital degeneracy and as a near-itinerant magnet which can be driven metallic with moderate applied pressure. Here, we report on our recent neutron di raction and inelastic scattering measurements on powders with minimal cation site disorder. Our main new result is the identification of a weak (Δa/a ~ 10–4), first order structural phase transition at T* = 90 K, the same temperature where spin canting was seen in recent single crystal measurements. This transition is characterized by amore » short-range distortion of oxygen octahedral positions, and inelastic data further establish a weak 1.25meV spin gap at low temperature. Together, these findings provide strong support for the local orbital picture and the existence of an orbital glass state at temperatures below T*.« less

    16. Structural Evolution in Atomic Nuclei: Residual Interactions, Quantum Phase Transitions and the Emergence of Collectivity

      SciTech Connect (OSTI)

      Casten, R. F.

      2007-10-26

      A synoptic view of the evolution of structure with Z and N in nuclei is beginning to emerge from the confiuence of new experimental results on phase transitional behavior, newly proposed many-body symmetries for critical point nuclei, a new generation of solvable collective models, powerful approaches to viewing the systematics of nuclear properties based on simple models of residual interactions, and advances in microscopic calculations of medium mass and heavy nuclei. A recent compilation of nuclear masses has contributed by permitting empirical extractions of new p-n interaction strengths of the last protons with the last neutrons in many nuclei across the nuclear chart. A number of these developments will be discussed with an eye to the opportunities and challenges they provide for the future, especially in the era of next-generation exotic beam facihties throughout the world.

    17. Enhanced sensitivity to the fine-structure-constant variation in the Th IV atomic clock transition

      SciTech Connect (OSTI)

      Flambaum, V. V.; Porsev, S. G.

      2009-12-15

      Our calculations have shown that the 5f{sub 5/2}-7s{sub 1/2} 23 131 cm{sup -1} transition from the ground state in the ion Th{sup 3+} is very sensitive to the temporal variation of the fine-structure constant alpha=e{sup 2}/(Planck constant/2pi)c (q=-75 300 cm{sup -1}). The line is very narrow, the ion has been trapped and laser cooled, and the positive shifter line 5f{sub 5/2}-5f{sub 7/2} 4325 cm{sup -1} (q=+2900 cm{sup -1}) may be used as a reference. A comparison may also be made with a positive shifter in another atom or ion. This makes Th{sup 3+} a good candidate to search for the alpha variation.

    18. Unravelling structural ambiguities in lithium- and manganese-rich transition metal oxides

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

      Shukla, Alpesh Khushalchand; Ramasse, Quentin M.; Ophus, Colin; Duncan, Hugues; Hage, Fredrik; Chen, Guoying

      2015-10-29

      Although Li- and Mn-rich transition metal oxides have been extensively studied as high-capacity cathode materials for Li-ion batteries, the crystal structure of these materials in their pristine state is not yet fully understood. Here we apply complementary electron microscopy and spectroscopy techniques at multi-length scale on well-formed Li1.2(Ni0.13Mn0.54Co0.13)O2 crystals with two different morphologies as well as two commercially available materials with similar compositions, and unambiguously describe the structural make-up of these samples. Systematically observing the entire primary particles along multiple zone axes reveals that they are consistently made up of a single phase, save for rare localized defects and amore » thin surface layer on certain crystallographic facets. Finally and more specifically, we show the bulk of the oxides can be described as an aperiodic crystal consisting of randomly stacked domains that correspond to three variants of monoclinic structure, while the surface is composed of a Co- and/or Ni-rich spinel with antisite defects.« less

    19. Thermoelectric material including a multiple transition metal-doped type I clathrate crystal structure

      DOE Patents [OSTI]

      Yang, Jihui; Shi, Xun; Bai, Shengqiang; Zhang, Wenqing; Chen, Lidong; Yang, Jiong

      2012-01-17

      A thermoelectric material includes a multiple transition metal-doped type I clathrate crystal structure having the formula A.sub.8TM.sub.y.sub.1.sup.1TM.sub.y.sub.2.sup.2 . . . TM.sub.y.sub.n.sup.nM.sub.zX.sub.46-y.sub.1.sub.-y.sub.2.sub.- . . . -y.sub.n.sub.-z. In the formula, A is selected from the group consisting of barium, strontium, and europium; X is selected from the group consisting of silicon, germanium, and tin; M is selected from the group consisting of aluminum, gallium, and indium; TM.sup.1, TM.sup.2, and TM.sup.n are independently selected from the group consisting of 3d, 4d, and 5d transition metals; and y.sub.1, y.sub.2, y.sub.n and Z are actual compositions of TM.sup.1, TM.sup.2, TM.sup.n, and M, respectively. The actual compositions are based upon nominal compositions derived from the following equation: z=8q.sub.A-|.DELTA.q.sub.1|y.sub.1-|.DELTA.q.sub.2|y.sub.2- . . . -|.DELTA.q.sub.n|y.sub.n, wherein q.sub.A is a charge state of A, and wherein .DELTA.q.sub.1, .DELTA.q.sub.2, .DELTA.q.sub.n are, respectively, the nominal charge state of the first, second, and n-th TM.

    20. Structural study of a bent-core liquid crystal showing the B{sub 1}-B{sub 2} transition

      SciTech Connect (OSTI)

      Folcia, Cesar Luis; Etxebarria, J.; Ortega, J.; Ros, M. B.

      2006-09-15

      An experimental study of the B{sub 1}-B{sub 2} transition is carried out in a bent-core liquid crystal. The study is essentially based on x-ray measurements as a function of temperature. The B{sub 1}-B{sub 2} transition is extremely unusual and implies a deep structural change from a columnar phase to a lamellar phase. We have found that the B{sub 1} phase in our compound is similar to the so-called B{sub 1} reversed phase, with an additional splay of the polarization in the columns. On approaching the B{sub 2} phase the width of the cross section of the columns increases. The transition is clearly first order, with a large hysteresis though the enthalpy content is very small. A possible mechanism for the transition is briefly sketched.

    1. Structure, phase transitions, and isotope effects in [(CH3)4N]2PuCl6

      SciTech Connect (OSTI)

      Wilson, Richard E.

      2015-11-02

      The single crystal X-ray diffraction structure of [(CH3)4N]2PuCl6 is presented for the first time, resolving long standing confusion and speculation regarding the structure of this compound in the literature. A temperature dependent study of this compound shows that the structure of [(CH3)4N]2PuCl6 undergoes no fewer than two phase transitions between 100 and 360 K. The phase of [(CH3)4N]2PuCl6 at room temperature is Fd-3c a = 26.012(3) Å. At 360 K, the structure is in space group Fm-3m with a = 13.088(1) Å. The plutonium octahedra and tetramethylammonium cations undergo a rotative displacement and the degree of rotation varies with temperature, giving rise to the phase transition from Fm-3m to Fd-3c as the crystal is cooled. Synthesis and structural studies of the deuterated salt [(CD3)4N]2PuCl6 suggest that there is an isotopic effect associated with this phase transition as revealed by a changing transition temperature in the deuterated versus protonated compound indicating that the donor-acceptor interactions between the tetramethylammonium cations and the hexachloroplutonate anions are driving the phase transformation.

    2. Electronic Reconstruction through the Structural and Magnetic Transitions in Detwinned NaFeAs

      SciTech Connect (OSTI)

      Yi, M.; Lu, D.H.; Moore, R.G.; Kihou, K; Lee, C-H; Iyo, A.; Eisaki, H.; Yoshida, T; Fujimori, A; Shen, Z-X

      2012-05-25

      We use angle-resolved photoemission spectroscopy to study twinned and detwinned iron pnictide compound NaFeAs. Distinct signatures of electronic reconstruction are observed to occur at the structural (T{sub S}) and magnetic (T{sub SDW}) transitions. At T{sub S}, C{sub 4} rotational symmetry is broken in the form of an anisotropic shift of the orthogonal d{sub xz} and d{sub yz} bands. The magnitude of this orbital anisotropy rapidly develops to near completion upon approaching T{sub SDW}, at which temperature band folding occurs via the antiferromagnetic ordering wave vector. Interestingly, the anisotropic band shift onsetting at T{sub S} develops in such a way to enhance the nesting conditions in the C{sub 2} symmetric state, hence is intimately correlated with the long range collinear AFM order. Furthermore, the similar behaviors of the electronic reconstruction in NaFeAs and Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} suggests that this rapid development of large orbital anisotropy between T{sub S} and T{sub SDW} is likely a general feature of the electronic nematic phase in the iron pnictides, and the associated orbital fluctuations may play an important role in determining the ground state properties.

    3. Reactive sputter deposition of pyrite structure transition metal disulfide thin films: Microstructure, transport, and magnetism

      SciTech Connect (OSTI)

      Baruth, A.; Manno, M.; Narasimhan, D.; Shankar, A.; Zhang, X.; Johnson, M.; Aydil, E. S.; Leighton, C. [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

      2012-09-01

      Transition metal disulfides crystallizing in the pyrite structure (e.g., TMS{sub 2}, with TM = Fe, Co, Ni, and Cu) are a class of materials that display a remarkably diverse array of functional properties. These properties include highly spin-polarized ferromagnetism (in Co{sub 1-x}Fe{sub x}S{sub 2}), superconductivity (in CuS{sub 2}), an antiferromagnetic Mott insulating ground state (in NiS{sub 2}), and semiconduction with close to optimal parameters for solar absorber applications (in FeS{sub 2}). Exploitation of these properties in heterostructured devices requires the development of reliable and reproducible methods for the deposition of high quality pyrite structure thin films. In this manuscript, we report on the suitability of reactive sputter deposition from metallic targets in an Ar/H{sub 2}S environment as a method to achieve exactly this. Optimization of deposition temperature, Ar/H{sub 2}S pressure ratio, and total working gas pressure, assisted by plasma optical emission spectroscopy, reveals significant windows over which deposition of single-phase, polycrystalline, low roughness pyrite films can be achieved. This is illustrated for the test cases of the ferromagnetic metal CoS{sub 2} and the diamagnetic semiconductor FeS{sub 2}, for which detailed magnetic and transport characterization are provided. The results indicate significant improvements over alternative deposition techniques such as ex situ sulfidation of metal films, opening up exciting possibilities for all-sulfide heterostructured devices. In particular, in the FeS{sub 2} case it is suggested that fine-tuning of the sputtering conditions provides a potential means to manipulate doping levels and conduction mechanisms, critical issues in solar cell applications. Parenthetically, we note that conditions for synthesis of phase-pure monosulfides and thiospinels are also identified.

    4. THE TRANSIT LIGHT CURVE OF AN EXOZODIACAL DUST CLOUD

      SciTech Connect (OSTI)

      Stark, Christopher C.

      2011-10-15

      Planets embedded within debris disks gravitationally perturb nearby dust and can create clumpy, azimuthally asymmetric circumstellar ring structures that rotate in lock with the planet. The Earth creates one such structure in the solar zodiacal dust cloud. In an edge-on system, the dust 'clumps' periodically pass in front of the star as the planet orbits, occulting and forward-scattering starlight. In this paper, we predict the shape and magnitude of the corresponding transit signal. To do so, we model the dust distributions of collisional, steady-state exozodiacal clouds perturbed by planetary companions. We examine disks with dusty ring structures formed by the planet's resonant trapping of in-spiraling dust for a range of planet masses and semi-major axes, dust properties, and disk masses. We synthesize edge-on images of these models and calculate the transit signatures of the resonant ring structures. The transit light curves created by dusty resonant ring structures typically exhibit two broad transit minima that lead and trail the planetary transit. We find that Jupiter-mass planets embedded within disks hundreds of times denser than our zodiacal cloud can create resonant ring structures with transit depths up to {approx}10{sup -4}, possibly detectable with Kepler. Resonant rings produced by planets more or less massive than Jupiter produce smaller transit depths. Observations of these transit signals may provide upper limits on the degree of asymmetry in exozodiacal clouds.

    5. Magnetic and Structural Phase Transitions in the Spinel Compound Fe1+xCr2 xO4

      SciTech Connect (OSTI)

      Ma, Jie; Garlea, Vasile O; Rondinone, Adam Justin; Aczel, Adam A; Calder, Stuart A; Dela Cruz, Clarina R; Sinclair, R.; Tian, Wei; Chi, Songxue; Kiswandhi, Andhika; Brooks, James S.; Zhou, Haidong; Matsuda, Masaaki

      2014-01-01

      Neutron diffraction, X-ray diffraction, magnetic susceptibility, and specific heat measurements have been used to investigate the magnetic and structural phase transitions of the spinel system Fe1+xCr2 xO4 (0.0 x 1.0). The temperature versus Fe concentration (x) phase diagram contains two magnetically ordered phases and four structural phases below 420 K. The complicated transitions are closely related to the change in the spin and orbital degrees of freedom induced by substitution of Fe ions for Cr ions. The systematic change in the crystal structure is explained by the combined effects of Jahn-Teller distortion, spin-lattice interaction, Fe2+-Fe3+ hopping, and disorder among Fe2+, Fe3+, and Cr3+ ions.

    6. The synthesis and structure of new transition metal lithium calcium nitride compounds

      SciTech Connect (OSTI)

      Hunting, Janet L.; Szymanski, Marta M.; Kowalsick, Amanda L.; Downie, Craig M.; DiSalvo, Francis J.

      2013-01-15

      Three new nitrides, Li{sub 3}Ca{sub 2}V{sub 0.79}Nb{sub 0.21}N{sub 4}, Li{sub 2}Ca{sub 2.67}Nb{sub 0.33}N{sub 3} and Li{sub 12}Ca{sub 9}W{sub 5}N{sub 20}, were synthesized in sealed niobium tubes using lithium nitride as a flux at temperatures ranging from 800 Degree-Sign C to 1050 Degree-Sign C. In all of these compounds, the transition metals are coordinated tetrahedrally by nitrogen; these tetrahedra are isolated from each other. Bullet Li{sub 3}Ca{sub 2}V{sub 0.79}Nb{sub 0.21}N{sub 4}, space group P2{sub 1}/m (no. 11), cell parameters a=5.7669(8) A, b=6.9123(9) A, c=6.0116(12) A, {beta}=90.727(9) Degree-Sign , Z=2, has a shared vanadium/niobium tetrahedral position which shares vertices with the tetrahedrally-coordinated lithium position. Bullet Li{sub 2}Ca{sub 2.67}Nb{sub 0.33}N{sub 3}, space group Req /o(3, Macron )m (no. 166), cell parameters a=3.6311(2) A, c=29.459(3) A, Z=3, contains a disordered tetrahedral calcium/niobium position, an octahedral calcium position and a triangularly coordinated lithium position. Bullet Li{sub 12}Ca{sub 9}W{sub 5}N{sub 20}, space group C2/c (no. 15), cell parameters a=27.7347(19) A, b=8.6652(6) A, c=10.7685(7) A, {beta}=110.314(2) Degree-Sign , Z=4, contains three crystallographically different tungsten positions as well as one disordered lithium position. - Graphical abstract: Crystal structure of Li{sub 3}Ca{sub 2}V{sub 0.79}Nb{sub 0.21}N{sub 4} depicting the chains of edge-sharing LiN{sub 4} (light hatching) and (V/Nb)N{sub 4} (dark hatching) tetrahedra viewed approximately along the [100] direction. Calcium atoms are shown as open circles and nitrogen atoms are colored black. Highlights: Black-Right-Pointing-Pointer Three new lithium calcium nitrides are synthesized. Black-Right-Pointing-Pointer Lithium nitride flux used in synthesis. Black-Right-Pointing-Pointer Structures contain isolated tetrahedrally coordinated transition metals. Black-Right-Pointing-Pointer Li{sub 12}Ca{sub 9}W{sub 5}N{sub 20} contains three

    7. Depth Optimization Study

      DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

      Kawase, Mitsuhiro

      2009-11-22

      The zipped file contains a directory of data and routines used in the NNMREC turbine depth optimization study (Kawase et al., 2011), and calculation results thereof. For further info, please contact Mitsuhiro Kawase at kawase@uw.edu. Reference: Mitsuhiro Kawase, Patricia Beba, and Brian Fabien (2011), Finding an Optimal Placement Depth for a Tidal In-Stream Conversion Device in an Energetic, Baroclinic Tidal Channel, NNMREC Technical Report.

    8. Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability

      SciTech Connect (OSTI)

      Yu, Xiqian; Hu, Enyuan; Bak, Seongmin; Zhou, Yong -Ning; Yang, Xiao -Qing

      2015-12-07

      Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. Furthermore, we also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue. As a result, it is widely accepted that the thermal instability of the cathodes is one of the most critical factors in thermal runaway and related safety problems.

    9. Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability

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

      Yu, Xiqian; Hu, Enyuan; Bak, Seongmin; Zhou, Yong -Ning; Yang, Xiao -Qing

      2015-12-07

      Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. Furthermore, we also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue. As a result, it is widely accepted that the thermal instability of themore »cathodes is one of the most critical factors in thermal runaway and related safety problems.« less

    10. Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability

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

      Yu, Xiqian; Hu, Enyuan; Bak, Seongmin; Zhou, Yong -Ning; Yang, Xiao -Qing

      2015-12-07

      Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. Furthermore, we also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue. As a result, it is widely accepted that the thermal instability of themore » cathodes is one of the most critical factors in thermal runaway and related safety problems.« less

    11. Tuning the magnetic and structural phase transitions of PrFeAsO via Fe/Ru spin dilution

      SciTech Connect (OSTI)

      Yiu, Yuen; Bonfa, Pietro; Sanna, Samuele; De Renzi, Roberto; Caretta, Pietro; McGuire, Michael A; Huq, Ashfia; Nagler, Stephen E

      2014-01-01

      Neutron diffraction and muon spin relaxation measurements are used to obtain a detailed phase diagram of PrFe1{xRuxAsO. The isoelectronic substitution of Ru for Fe acts eectively as spin dilution, suppressing both the structural and magnetic phase transitions. The temperature, TS, of the tetragonal-orthorhombic structural phase transition decreases gradually as a function of x. Slightly below TS coherent precessions of the muon spin are observed corresponding to static magnetism, possibly re ecting a signicant magneto-elastic coupling in the FeAs layers. Short range order in both the Fe and Pr moments persists for higher levels of x. The static magnetic moments disappear at a concentration coincident with that expected for percolation of the J1 - J2 square lattice model.

    12. Structural response in FeCl2 (iron chloride) to pressure-induced electro-magnetic transitions

      SciTech Connect (OSTI)

      Taylor, R D; Rozenberg, G Kh; Pasternak, M P; Gorodetsky, P; Xu, W M; Dubrovinsky, L S; Le Bihan, T L

      2009-01-01

      High pressure (HP) synchrotron x-ray diffraction studies were carried out in FeCl{sub 2} together with resistivity (R) studies, at various temperatures and pressures to 65 GPa using diamond anvil cells. This work follows a previous HP {sup 57}Fe Mossbauer study in which two pressure-induced (PI) electronic transitions were found interpreted as: (i) quenching of the orbital-term contribution to the hyperfine field concurring with a tilting of the magnetic moment by 55 degrees and (ii) collapse of the magnetism concurring with a sharp decrease of the isomer shift (IS). The R(P,T) studies affirm that the cause the collapse of the magnetism is a PI p-d correlation breakdown, leading to an insulator-metal transition at {approx}45 GPa and is not due to a spi-Ir,crossover (S=2 {yields} S=0). The structure response to the pressure evolution of the two electronic phase transitions starting at low pressures (LP), through an intermediate phase (IP) 30-57 GPa, and culminating in a high-pressure phase (HP), P >32 GPa, can clearly be quantified. The IP-HP phases coexist through the 32-57 GPa range in which the HP abundance increases monotonically at the expense of the IP phase. At the LP-IP interface no volume change is detected, yet the c-axis increases and the a-axis shrinks by 0.21 Angstroms and 0.13 Angstroms, respectively. The fit of the equation of state of the combined LP-IP phases yields a bulk modulus K{sub 0} = 35.3(1.8) GPa. The intralayer CI-CI distances increases, but no change is observed in Fe-CI bond-length nor are there substantial changes in the interlayer spacing. The pressure-induced electronic IP-HP transition leads to a first-order structural phase transition characterized by a decrease in Fe-CI bond length and an abrupt drop in V(P) by {approx}3.5% accompanying the correlation breakdown. In this transition no symmetry change is detected,and the XRD data could be satisfactorily fitted with the CdI{sub 2} structure. The bulk modulus of the HP phase is

    13. Pressure-Induced Structural Phase Transition in CeNi: X-ray and Neutron Scattering Studies and First-Principles Calculations

      SciTech Connect (OSTI)

      Mirmelstein, A.; Podlesnyak, Andrey A.; dos Santos, Antonio M.; Ehlers, Georg; Kerbel, O.; Matvienko, V.; Sefat, A. S.; Saporov, B.; Halder, G. J.; Tobin, J. G.

      2015-08-03

      The pressure-induced structural phase transition in the intermediate-valence compound CeNi has been investigated by x-ray and neutron powder diffraction techniques. It is shown that the structure of the pressure-induced CeNi phase (phases) can be described in terms of the Pnma space group. Equations of state for CeNi on both sides of the phase transition are derived and an approximate P-T phase diagram is suggested for P<8 GPa and T<300 K. The observed Cmcm→Pnma structural transition is then analyzed using density functional theory calculations, which successfully reproduce the ground state volume, the phase transition pressure, and the volume collapse associated with the phase transition.

    14. Pressure-Induced Structural Phase Transition in CeNi: X-ray and Neutron Scattering Studies and First-Principles Calculations

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

      Mirmelstein, A.; Podlesnyak, Andrey A.; dos Santos, Antonio M.; Ehlers, Georg; Kerbel, O.; Matvienko, V.; Sefat, A. S.; Saporov, B.; Halder, G. J.; Tobin, J. G.

      2015-08-03

      The pressure-induced structural phase transition in the intermediate-valence compound CeNi has been investigated by x-ray and neutron powder diffraction techniques. It is shown that the structure of the pressure-induced CeNi phase (phases) can be described in terms of the Pnma space group. Equations of state for CeNi on both sides of the phase transition are derived and an approximate P-T phase diagram is suggested for P<8 GPa and T<300 K. The observed Cmcm→Pnma structural transition is then analyzed using density functional theory calculations, which successfully reproduce the ground state volume, the phase transition pressure, and the volume collapse associated withmore » the phase transition.« less

    15. Structural transitions of ternary imide Li{sub 2}Mg(NH){sub 2} for hydrogen storage

      SciTech Connect (OSTI)

      Liang, C.; Gao, M. X.; Pan, H. G. Liu, Y. F.

      2014-08-25

      Phase transitions and energetic properties of Li{sub 2}Mg(NH){sub 2} with different crystal structures are investigated by experiments and first-principles calculations. The Li{sub 2}Mg(NH){sub 2} with the primitive cubic and orthorhombic structure is obtained by dynamically dehydrogenating a Mg(NH{sub 2}){sub 2}-2LiH mixture up to 280?C under an initial vacuum and 9.0?bars H{sub 2}, respectively. It is found that the obtained orthorhombic Li{sub 2}Mg(NH){sub 2} is converted to a primitive cubic structure as the dehydrogenation temperature is further increased to 400?C or performed by a 36?h of high-energetic ball milling. Moreover, the primitive cubic phase can be converted to an orthorhombic phase after heating at 280?C under 9.0?bars H{sub 2} for 1?h. Thermodynamic calculations show that the orthorhombic phase is the ground state structure of Li{sub 2}Mg(NH){sub 2}. The mechanism for phase transitions of Li{sub 2}Mg(NH){sub 2} is also discussed from the angle of energy.

    16. Structural cooling fluid tube for supporting a turbine component and supplying cooling fluid to transition section

      SciTech Connect (OSTI)

      Charron, Richard; Pierce, Daniel

      2015-08-11

      A shaft cover support for a gas turbine engine is disclosed. The shaft cover support not only provides enhanced support to a shaft cover of the gas turbine engine, but also includes a cooling fluid chamber for passing fluids from a rotor air cooling supply conduit to an inner ring cooling manifold. Furthermore, the shaft cover support may include a cooling shield supply extending from the cooling fluid chamber between the radially outward inlet and the radially inward outlet on the radially extending region and in fluid communication with the cooling fluid chamber for providing cooling fluids to a transition section. The shaft cover support may also provide additional stiffness and reduce interference of the flow from the compressor. In addition, the shaft cover support accommodates a transition section extending between compressor and turbine sections of the gas turbine engine.

    17. Time-resolved x-ray diffraction and electrical resistance measurements of structural phase transitions in zirconium

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

      Velisavljevic, N.; Sinogeikin, S.; Saavedra, R.; Chellappa, R. S.; Rothkirch, A.; Dattelbaum, D. M.; Konopkova, Z.; Liermann, H. -P.; Bishop, M.; Tsoi, G. M.; et al

      2014-05-07

      Here, we have designed a portable pressure controller module to tune compression rates and maximum pressures attainable in a standard gas-membrane diamond anvil cell (DAC). During preliminary experiments, performed on zirconium (Zr) metal sample, pressure jumps of up to 80 GPa were systematically obtained in less than 0.2s (resulting in compression rate of few GPa/s up to more than 400 GPa/s). In-situ x-ray diffraction and electrical resistance measurements were performed simultaneously during this rapid pressure increase to provide the first time resolved data on α → ω → β structural evolution in Zr at high pressures. Direct control of compressionmore » rates and peak pressures, which can be held for prolonged time, allows for investigation of structural evolution and kinetics of structural phase transitions of materials under previously unexplored compression rate-pressure conditions that bridge traditional static and shock/dynamic experimental platforms.« less

    18. Structural and magnetic phase transitions in CeCu6-xTx (T = Ag,Pd)

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

      Poudel, Lekhanath N.; De la cruz, Clarina; Payzant, E. Andrew; Koehler, Michael R.; May, Andrew F.; Garlea, Vasile O.; Taylor, Alice E.; Parker, David S.; Cao, Huibo B.; McGuire, Michael A.; et al

      2015-12-15

      The structural and the magnetic properties of CeCu6-xAgx (0 ≤ x ≤ 0.85) and CeCu6-xPdx (0 ≤ x ≤ 0.4) have been studied using neutron diffraction, resonant ultrasound spectroscopy (RUS), x-ray diffraction measurements, and first principles calculations. The structural and magnetic phase diagrams of CeCu6-xAgx and CeCu6-xPdx as a function of Ag/Pd composition are reported. The end member, CeCu6, undergoes a structural phase transition from an orthorhombic (Pnma) to a monoclinic (P21/c) phase at 240 K. In CeCu6-xAgx, the structural phase transition temperature (Ts) decreases linearly with Ag concentration and extrapolates to zero at xS ≈ 0.1. The structural transitionmore » in CeCu6-xPdx remains unperturbed with Pd substitution within the range of our study. The lattice constant b slightly decreases with Ag/Pd doping, whereas a and c increase with an overall increase in the unit cell volume. Both systems, CeCu6-xAgx and CeCu6-xPdx, exhibit a magnetic quantum critical point (QCP), at x ≈ 0.2 and x ≈ 0.05, respectively. Near the QCP, long range antiferromagnetic ordering takes place at an incommensurate wave vector (δ1 0 δ2), where δ1 ~ 0.62, δ2 ~ 0.25, x = 0.125 for CeCu6-xPdx and δ1 ~ 0.64, δ2 ~ 0.3, x = 0.3 for CeCu6-xAgx. As a result, the magnetic structure consists of an amplitude modulation of the Ce moments which are aligned along the c axis of the orthorhombic unit cell.« less

    19. Variable depth core sampler

      DOE Patents [OSTI]

      Bourgeois, Peter M.; Reger, Robert J.

      1996-01-01

      A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

    20. Variable depth core sampler

      DOE Patents [OSTI]

      Bourgeois, P.M.; Reger, R.J.

      1996-02-20

      A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

    1. Structural and magnetic properties of transition metal substituted BaFe{sub 2}As{sub 2} compounds studied by x-ray and neutron scattering

      SciTech Connect (OSTI)

      Kim, Min Gyu

      2012-08-28

      The purpose of my dissertation is to understand the structural and magnetic properties of the newly discovered FeAs-based superconductors and the interconnection between superconductivity, antiferromagnetism, and structure. X-ray and neutron scattering techniques are powerful tools to directly observe the structure and magnetism in this system. I used both xray and neutron scattering techniques on di#11;erent transition substituted BaFe2As2 compounds in order to investigate the substitution dependence of structural and magnetic transitions and try to understand the connections between them.

    2. Electronic structure reconstruction across the antiferromagnetic transition in TaFe₁̣₂₃Te₃ spin ladder

      SciTech Connect (OSTI)

      Xu, Min; Wang, Li -Min; Peng, Rui; Ge, Qing -Qin; Chen, Fei; Ye, Zi -Rong; Zhang, Yan; Chen, Su -Di; Xia, Miao; Liu, Rong -Hua; Arita, M.; Shimada, K.; Namatame, H.; Taniguchi, M.; Matsunami, M.; Kimura, S.; Shi, Ming; Chen, Xian -Hui; Yin, Wei -Guo; Ku, Wei; Xie, Bin -Ping; Feng, Dong -Lai

      2015-02-01

      With angle-resolved photoemission spectroscopy, we studied the electronic structure of TaFe₁̣₂₃Te₃, a two-leg spin ladder compound with a novel antiferromagnetic ground state. Quasi-two-dimensional Fermi surface is observed, with sizable inter-ladder hopping. Moreover, instead of observing an energy gap at the Fermi surface in the antiferromagnetic state, we observed the shifts of various bands. Combining these observations with density-functional-theory calculations, we propose that the large scale reconstruction of the electronic structure, caused by the interactions between coexisting itinerant electrons and local moments, is most likely the driving force of the magnetic transition. Thus TaFe₁̣₂₃Te₃ serves as a simpler platform that contains similar ingredients as the parent compounds of iron-based superconductors.

    3. Electronic structure reconstruction across the antiferromagnetic transition in TaFe₁̣₂₃Te₃ spin ladder

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

      Xu, Min; Wang, Li -Min; Peng, Rui; Ge, Qing -Qin; Chen, Fei; Ye, Zi -Rong; Zhang, Yan; Chen, Su -Di; Xia, Miao; Liu, Rong -Hua; et al

      2015-02-01

      With angle-resolved photoemission spectroscopy, we studied the electronic structure of TaFe₁̣₂₃Te₃, a two-leg spin ladder compound with a novel antiferromagnetic ground state. Quasi-two-dimensional Fermi surface is observed, with sizable inter-ladder hopping. Moreover, instead of observing an energy gap at the Fermi surface in the antiferromagnetic state, we observed the shifts of various bands. Combining these observations with density-functional-theory calculations, we propose that the large scale reconstruction of the electronic structure, caused by the interactions between coexisting itinerant electrons and local moments, is most likely the driving force of the magnetic transition. Thus TaFe₁̣₂₃Te₃ serves as a simpler platform that containsmore » similar ingredients as the parent compounds of iron-based superconductors.« less

    4. Structural and Dynamic Characterization of Amorphous Solids and Associated Phase Transitions. Final Report

      SciTech Connect (OSTI)

      Yarger, J. L.

      2000-08-15

      The effect of hydrostatic pressure on the structure of glasses is not well understood. There is extensive evidence now indicating that glasses undergo structural transformation upon application of pressure. These transformations are usually evidenced by changes in density, sound velocity, and structural changes from diffraction measurements (x-ray and neutron). In vitreous GeO{sub 2}, a change in Ge-coordination from 4-6 is evidenced on the application of pressure. The coordination change reverts back to 4 on releasing the pressure indicating that the structural transformation is reversible with pressure. But a shift towards higher Q (inverse space) of the first sharp diffraction peak (FSDP) on the pressure compacted v-SiO{sub 2} and v-GeO{sub 2} suggests that application of pressure has both reversible and irreversible components such that on the release of pressure, the glass remains in a permanently compacted state.

    5. Structural and magnetic phase transitions near optimal superconductivity in BaFe2(As1-xPx)2

      SciTech Connect (OSTI)

      Hu, Ding; Lu, Xingye; Zhang, Wenliang; Luo, Huiqian; Li, Shiliang; Wang, Peipei; Chen, Genfu; Han, Fei; Banjara, Shree R.; Sapkota, A.; Kreyssig, A.; Goldman, A. I.; Yamani, Z.; Niedermayer, Christof; Skoulatos, Markos; Georgii, Robert; Keller, T.; Wang, Pengshuai; Yu, Weiqiang; Dai, Pengcheng

      2015-04-17

      In this study, we use nuclear magnetic resonance (NMR), high-resolution x-ray and neutron scattering to study structural and magnetic phase transitions in phosphorus-doped BaFe2(As1-xPx)2. Thus, previous transport, NMR, specific heat, and magnetic penetration depth measurements have provided compelling evidence for the presence of a quantum critical point (QCP) near optimal superconductivity at x = 0.3. However, we show that the tetragonal-to-orthorhombic structural (Ts) and paramagnetic to antiferromagnetic (AF, TN) transitions in BaFe2(As1-xPx)2 are always coupled and approach to TN ≈ Ts ≥ Tc (≈ 29 K) for x = 0.29 before vanishing abruptly for x ≥ 0.3. These results suggest that AF order in BaFe2(As1-xPx)2 disappears in a weakly first order fashion near optimal superconductivity, much like the electron-doped iron pnictides with an avoided QCP.

    6. FINAL TECHNICAL REPORT Synthetic, Structural and Mechanistic Investigations of Olefin Polymerization Catalyzed by Early Transition Metal Compounds

      SciTech Connect (OSTI)

      Bercaw, John E.

      2014-05-23

      The goal of this project is to develop new catalysts and provide understanding of ligand effects on catalyst composition in order to guide development of superior catalyst systems for polymerization of olefins. Our group is designing and synthesizing new “LX2”,“pincer” type ligands and complexing early transition metals to afford precatalysts. In a collaboration with Hans Brintzinger from the University of Konstanz, we are also examining the structures of the components of catalyst systems obtained from reaction of zirconocene dichlorides with aluminum alkyls and aluminum hydrides. Such systems are currently used commercially to produce polyolefins, but the nature of the active and dormant species as well as the mechanisms of their interconversions are not understood. New information on catalyst design and performance may lead to new types of polymers and/or new chemical transformations between hydrocarbons and transition metal centers, ultimately contributing to the development of catalytic reactions for the production of fuels, commodity and polymeric materials.

    7. Structural phase transitions in Bi2Se3 under high pressure

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

      Yu, Zhenhai; Gu, Genda; Wang, Lin; Hu, Qingyang; Zhao, Jinggeng; Yan, Shuai; Yang, Ke; Sinogeikin, Stanislav; Mao, Ho -kwang

      2015-11-02

      Raman spectroscopy and angle dispersive X-ray diffraction (XRD) experiments of bismuth selenide (Bi2Se3) have been carried out to pressures of 35.6 and 81.2 GPa, respectively, to explore its pressure-induced phase transformation. The experiments indicate that a progressive structural evolution occurs from an ambient rhombohedra phase (Space group (SG): R-3m) to monoclinic phase (SG: C2/m) and eventually to a high pressure body-centered tetragonal phase (SG: I4/mmm). Evidenced by our XRD data up to 81.2 GPa, the Bi2Se3 crystallizes into body-centered tetragonal structures rather than the recently reported disordered body-centered cubic (BCC) phase. Furthermore, first principles theoretical calculations favor the viewpoint thatmore » the I4/mmm phase Bi2Se3 can be stabilized under high pressure (>30 GPa). Remarkably, the Raman spectra of Bi2Se3 from this work (two independent runs) are still Raman active up to ~35 GPa. Furthermore, it is worthy to note that the disordered BCC phase at 27.8 GPa is not observed here. The remarkable difference in atomic radii of Bi and Se in Bi2Se3 may explain why Bi2Se3 shows different structural behavior than isocompounds Bi2Te3 and Sb2Te3.« less

    8. Fine-structure calculations of energy levels, oscillator strengths, and transition probabilities for sulfur-like iron, Fe XI

      SciTech Connect (OSTI)

      Abou El-Maaref, A.; Ahmad, Mahmoud; Allam, S.H.

      2014-05-15

      Energy levels, oscillator strengths, and transition probabilities for transitions among the 14 LS states belonging to configurations of sulfur-like iron, Fe XI, have been calculated. These states are represented by configuration interaction wavefunctions and have configurations 3s{sup 2}3p{sup 4}, 3s3p{sup 5}, 3s{sup 2}3p{sup 3}3d, 3s{sup 2}3p{sup 3}4s, 3s{sup 2}3p{sup 3}4p, and 3s{sup 2}3p{sup 3}4d, which give rise to 123 fine-structure energy levels. Extensive configuration interaction calculations using the CIV3 code have been performed. To assess the importance of relativistic effects, the intermediate coupling scheme by means of the BreitPauli Hamiltonian terms, such as the one-body mass correction and Darwin term, and spinorbit, spinother-orbit, and spinspin corrections, are incorporated within the code. These incorporations adjusted the energy levels, therefore the calculated values are close to the available experimental data. Comparisons between the present calculated energy levels as well as oscillator strengths and both experimental and theoretical data have been performed. Our results show good agreement with earlier works, and they might be useful in thermonuclear fusion research and astrophysical applications. -- Highlights: Accurate atomic data of iron ions are needed for identification of solar corona. Extensive configuration interaction wavefunctions including 123 fine-structure levels have been calculated. The relativistic effects by means of the BreitPauli Hamiltonian terms are incorporated. This incorporation adjusts the energy levels, therefore the calculated values are close to experimental values.

    9. Couples Magnetic and Structural Transitions in High-Purity Dy and Gd5SbxGe4-x

      SciTech Connect (OSTI)

      Alexander S. Chernyshov

      2006-08-09

      Magnetic materials exhibiting magnetic phase transitions simultaneously with structural rearrangements of their crystal lattices hold a promise for numerous applications including magnetic refrigeration, magnetomechanical devices and sensors. We undertook a detailed study of a single crystal of dysprosium metal, which is a classical example of a system where magnetic and crystallographic sublattices can be either coupled or decoupled from one another. Magnetocaloric effect, magnetization, ac magnetic susceptibility, and heat capacity of high purity single crystals of dysprosium have been investigated over broad temperature and magnetic field intervals with the magnetic field vector parallel to either the a- or c-axes of the crystal. Notable differences in the behavior of the physical properties when compared to Dy samples studied in the past have been observed between 110 K and 125 K, and between 178 K and {approx}210 K. A plausible mechanism based on the formation of antiferromagnetic clusters in the impure Dy has been suggested in order to explain the reduction of the magnetocaloric effect in the vicinity of the Neel point. Experimental and theoretical investigations of the influence of commensurability effects on the magnetic phase diagram and the value of the magnetocaloric effect have been conducted. The presence of newly found anomalies in the physical properties has been considered as evidence of previously unreported states of Dy. The refined magnetic phase diagram of dysprosium with the magnetic field vector parallel to the a-axis of a crystal has been constructed and discussed. The magnetic and crystallographic properties of Gd{sub 5}Sb{sub x}Ge{sub 4-x} pseudo-binary system were studied by x-ray diffraction (at room temperature), heat capacity, ac-magnetic susceptibility, and magnetization in the temperature interval 5-320 K in magnetic fields up to 100 kOe. The magnetic properties of three composition (x = 0.5, 1,2) were examined in detail. The Gd{sub 5

    10. Direct probe of Mott-Hubbard to charge-transfer insulator transition and electronic structure evolution in transition-metal systems

      SciTech Connect (OSTI)

      Olalde-Velasco, P; Jimenez-Mier, J; Denlinger, JD; Hussain, Z; Yang, WL

      2011-07-11

      We report the most direct experimental verification of Mott-Hubbard and charge-transfer insulators through x-ray emission spectroscopy in transition-metal (TM) fluorides. The p-d hybridization features in the spectra allow a straightforward energy alignment of the anion-2p and metal-3d valence states, which visually shows the difference between the two types of insulators. Furthermore, in parallel with the theoretical Zaanen-Sawatzky-Allen diagram, a complete experimental systematics of the 3d Coulomb interaction and the 2p-3d charge-transfer energy is reported and could serve as a universal experimental trend for other TM systems including oxides.

    11. ARM - Measurement - Aerosol optical depth

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

      Sky-Scanning, Sun Tracking Atmospheric Research SAM : Sun and Aureole Measurement UAV-GNAT : UAV-General Atomics GNAT Value-Added Products AOD : Aerosol Optical Depth, derived from ...

    12. Structural evolution across the insulator-metal transition in oxygen-deficient BaTiO3-δ studied using neutron total scattering and Rietveld analysis

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

      Jeong, I.-K.; Lee, Seunghun; Jeong, Se-Young; Won, C. J.; Hur, N.; Llobet, A.

      2011-08-29

      Oxygen-deficient BaTiO3-δ exhibits an insulator-metal transition with increasing δ. We performed neutron total scattering measurements to study structural evolution across an insulator-metal transition in BaTiO3-δ. Despite its significant impact on resistivity, slight oxygen reduction (δ=0.09) caused only a small disturbance on the local doublet splitting of Ti-O bond. This finding implies that local polarization is well preserved under marginal electric conduction. In the highly oxygen-deficient metallic state (δ=0.25), however, doublet splitting of the Ti-O bond became smeared. The smearing of the local Ti-O doublet is complemented with long-range structural analysis and demonstrates that the metallic conduction in the highly oxygen-reducedmore » BaTiO3-δ is due to the appearance of nonferroelectric cubic lattice.« less

    13. Superconductivity versus structural phase transition in the closely related Bi2Rh3.5S2 and Bi2Rh3S2

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

      Kaluarachchi, Udhara S.; Xie, Weiwei; Lin, Qisheng; Taufour, Valentin; Bud'ko, Sergey L.; Miller, Gordon J.; Canfield, Paul C.

      2015-05-19

      Single crystals of Bi2Rh3S2 and Bi2Rh3.5S2 were synthesized by solution growth, and the crystal structures and thermodynamic and transport properties of both compounds were studied. In the case of Bi2Rh3S2, a structural first-order transition at around 165 K is identified by single-crystal diffraction experiments, with clear signatures visible in resistivity, magnetization, and specific heat data. No superconducting transition for Bi2Rh3S2 was observed down to 0.5 K. In contrast, no structural phase transition at high temperature was observed for Bi2Rh3.5S2; however, bulk superconductivity with a critical temperature, Tc ≈ 1.7 K, was observed. The Sommerfeld coefficient γ and the Debye temperaturemore » (ΘD) were found to be 9.41 mJ mol–1K–2 and 209 K, respectively, for Bi2Rh3S2, and 22 mJ mol–1K–2 and 196 K, respectively, for Bi2Rh3.5S2. As a result, the study of the specific heat in the superconducting state of Bi2Rh3.5S2 suggests that Bi2Rh3.5S2 is a weakly coupled, BCS superconductor.« less

    14. Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies

      SciTech Connect (OSTI)

      Daoud-Aladine, A.; Chapon, L. C.; Knight, K. S.; Martin, C.; Hervieu, M.; Brunelli, M.; Radaelli, P. G.

      2007-03-01

      The structural and magnetic properties of the hexagonal four-layer form of SrMnO{sub 3} have been investigated by combining magnetization measurements, electron diffraction, and high-resolution synchrotron x-ray and neutron powder diffraction. Below 350 K, there is subtle structural phase transition from hexagonal symmetry (space group P6{sub 3}/mmc) to orthorhombic symmetry (space group C222{sub 1}) where the hexagonal metric is preserved. The second-order phase transition involves a slight tilting of the corner-sharing Mn{sub 2}O{sub 9} units composed of two face-sharing MnO{sub 6} octahedra and the associated displacement of Sr{sup 2+} cations. The phase transition is described in terms of symmetry-adapted displacement modes of the high symmetry phase. Upon further cooling, long range magnetic order with propagation vector k=(0,0,0) sets in below 300 K. The antiferromagnetic structure, analyzed using representation theory, shows a considerably reduced magnetic moment indicating the crucial role played by direct exchange between Mn centers of the Mn{sub 2}O{sub 9} units.

    15. Binding energies and spatial structures of small carrier complexes in monolayer transition-metal dichalcogenides via diffusion Monte Carlo

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

      Mayers, Matthew Z.; Berkelbach, Timothy C.; Hybertsen, Mark S.; Reichman, David R.

      2015-10-09

      Ground-state diffusion Monte Carlo is used to investigate the binding energies and intercarrier radial probability distributions of excitons, trions, and biexcitons in a variety of two-dimensional transition-metal dichalcogenide materials. We compare these results to approximate variational calculations, as well as to analogous Monte Carlo calculations performed with simplified carrier interaction potentials. Our results highlight the successes and failures of approximate approaches as well as the physical features that determine the stability of small carrier complexes in monolayer transition-metal dichalcogenide materials. In conclusion, we discuss points of agreement and disagreement with recent experiments.

    16. Gender Transition Guidelines, Workplace

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

      Gender Transition Guidelines, Workplace

    17. Structurally-driven metal-insulator transition in Ca{sub 2}Ru{sub 1-x}Cr{sub x}O{sub 4} (0{<=}x<0.14): A single crystal X-ray diffraction study

      SciTech Connect (OSTI)

      Qi, T.F.; Ge, M.; Korneta, O.B.; Parkin, S.; De Long, L.E.; Cao, G.

      2011-04-15

      Correlation between structure and transport properties are investigated in high-quality single-crystals of Ca{sub 2}Ru{sub 1-x}Cr{sub x}O{sub 4} with 0structurally driven metal-insulator (MI) transition at 357 K. Upon chromium doping on the ruthenium site, the metal-insulator transition temperature (T{sub MI}) was drastically reduced, and is related to the competition between structural changes that occur upon Cr doping and with decreasing temperature. A strong suppression of structural distortions with increasing Cr substitution was identified. No clear T{sub MI} can be observed when x>13.5% and the system behaves as an insulator. Such a large, sharp metal-insulator transition and tuneable transition temperature may have potential applications in electronic devices. -- Graphical abstract: The metal-insulator transition temperature (T{sub MI}) was drastically reduced by Cr doping, and is closely related to the distortion of structure. Display Omitted Research highlights: {yields} The metal-insulator transition temperature (T{sub MI}) was drastically reduced by doping Cr into Ca{sub 2}RuO{sub 4} single crystal. {yields} Detailed single crystal structural analysis provided important insight into this structurally-driven metal-insulator transition. {yields} Negative Volume Thermal Expansion (NVTE) was observed with increasing temperature.

    18. Structures and phases transition in hexylenediammonium pentachlorobismuthate (III) [NH{sub 3}(CH{sub 2}){sub 6}NH{sub 3}]BiCl{sub 5} crystal

      SciTech Connect (OSTI)

      Ouasri, A.; Jeghnou, H.; Rhandour, A.; Roussel, P.

      2013-04-15

      The crystal structure of [NH{sub 3}(CH{sub 2}){sub 6}NH{sub 3}]BiCl{sub 5} was determined at: 223 K [P2{sub 1}2{sub 1}2{sub 1} (Z=4), a=7.788(1), b=13.886(2), c=13.972(2) Å], 308 K [P2{sub 1}/n (Z=8), a=19.972(3), b=7.772(2), c=20.166(3) Å, β=92.32(1)°] and 378 K [Pnma (Z=4), a=13911(2), b=7.834(7), c=14.457(2) Å]. It was consisted of isolated (BiCl{sub 5}{sup 2−}){sub n} anionic chains composed by distorted octahedra BiCl{sub 6}{sup 3−} sharing two corners and {sup +}NH{sub 3}(CH{sub 2}){sub 6}NH{sub 3}{sup +} cations placed in the free cavities between anionic chains. In the β phase, there are two crystallographically inequivalent cations and two one-dimensional anionic chains (BiCl{sub 5}{sup 2−}){sub n} in which BiCl{sub 6}{sup 3−} octahedra was doubly tilted and simply tilted. Two structural phase transitions at low and high temperatures α (P2{sub 1}2{sub 1}2{sub 1}, 223 K)↔β (P2{sub 1}/n, 308 K)↔γ (Pnma, 373 K) are observed and discussed. It was crystallographically showed that both anionic and cationic entities contribute to phase transitions mechanisms. The BiCl{sub 6}{sup 3−} octahedra were found to posses significant distortions on decreasing temperature and became more distorted in α (223 K) phase. It is argued that these deformations are caused by weak to moderate N--H···Cl hydrogen bonding. - Graphical abstract: Projection of the crystal structure of [NH{sub 3}(CH{sub 2}){sub 6}NH{sub 3}]BiCl{sub 5} down the a axis at 208 K. Highlights: ► The crystal shows two phase transitions: α(223 K)↔β(308 K)↔γ(373 K). ► A discontinuous transition may be occurred between α and β phases. ► The α↔β and β↔γ phase transitions are of first order. ► Both anionic and cationic motions contribute to phase transition mechanisms. ► The BiCl{sub 6}{sup 3−} octahedra showed significant distortions on decreasing temperature.

    19. Rotating drum variable depth sampler

      DOE Patents [OSTI]

      Nance, Thomas A.; Steeper, Timothy J.

      2008-07-01

      A sampling device for collecting depth-specific samples in silt, sludge and granular media has three chambers separated by a pair of iris valves. Rotation of the middle chamber closes the valves and isolates a sample in a middle chamber.

    20. Structural and magnetic phase transitions in Ca0.73Le0.27FeAs2 with electron-overdoped FeAs layers

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

      Jiang, Shan; Liu, Chang; Cao, Huibo; Birol, Turan; Allred, Jared M.; Tian, Wei; Liu, Lian; Cho, Kyuil; Krogstad, Matthew J.; Ma, Jie; et al

      2016-02-26

      We report a study of the Ca0.73La0.27FeAs2 single crystals. We unravel a monoclinic to triclinic phase transition at 58 K, and a paramagnetic to stripe antiferromagnetic (AFM) phase transition at 54 K, below which spins order 45° away from the stripe direction. Furthermore, we demonstrate this material is substantially structurally untwinned at ambient pressure with the formation of spin rotation walls (S-walls). Lastly, in addition to the central-hole and corner-electron Fermi pockets usually appearing in FPS, angle-resolved photoemission (ARPES) measurements resolve a Fermiology where an extra electron pocket of mainly As chain character exists at the Brillouin zone edge.

    1. Ultrasonic material hardness depth measurement

      DOE Patents [OSTI]

      Good, Morris S.; Schuster, George J.; Skorpik, James R.

      1997-01-01

      The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part.

    2. Ultrasonic material hardness depth measurement

      DOE Patents [OSTI]

      Good, M.S.; Schuster, G.J.; Skorpik, J.R.

      1997-07-08

      The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part. 12 figs.

    3. Neutron diffraction study of the crystal structure and structural phase transition of La{sub 0.7}Ca{sub 0.3-x}Sr{sub x}CrO{sub 3} (0<=x<=0.3)

      SciTech Connect (OSTI)

      Omoto, Kazuki; Norberg, Stefan T.; Hull, Steve; Aoto, Akimitsu; Hashimoto, Takuya

      2010-02-15

      The crystal structure of the La{sub 0.7}Ca{sub 0.3-x}Sr{sub x}CrO{sub 3} series, including the compositional and temperature dependence of the structural parameters, has been studied by variable temperature neutron diffraction measurements. The extent of the distortions from the ideal cubic perovskite structure has been evaluated quantitatively using the average bond lengths and the mean volumes of the [CrO{sub 6}] octahedron and [(La/Ca/Sr)O{sub 12}] polyhedron, and has been shown to decrease with increase of Sr content or temperature. At the structural phase transition from the orthorhombic (Pnma) structure to the rhombohedral (R3-barc) one, the volume of the [CrO{sub 6}] octahedron decreases whereas that of the [(La/Ca/Sr)O{sub 12}] polyhedron shows little difference, resulting in an overall decrease in the level of distortion. The change in the degree of distortion at the phase transition decreases with increase of Sr content, in agreement with the smaller variation of the enthalpy and volume for the specimens with higher Sr content. - Graphical abstract: Temperature dependence of parameter, PHI, representing the extent of distortion from the ideal cubic perovskite structure, for La{sub 0.7}Ca{sub 0.3}CrO{sub 3} (diamonds) and La{sub 0.7}Ca{sub 0.15}Sr{sub 0.15}CrO{sub 3} (circles) calculated from neutron diffraction patterns.

    4. Structural and magnetic phase transitions in CeCu6-xTx (T = Ag,Pd)

      SciTech Connect (OSTI)

      Poudel, Lekhanath N.; De la cruz, Clarina; Payzant, E. Andrew; Koehler, Michael R.; May, Andrew F.; Garlea, Vasile O.; Taylor, Alice E.; Parker, David S.; Cao, Huibo B.; McGuire, Michael A.; Tian, Wei; Matsuda, Masaaki; Jeen, Hyoung Jeen; Lee, Ho Nyung; Hong, Tao; Calder, Stuart A.; Lumsden, Mark D.; Zhou, Haidong; Keppens, Veerle; Mandrus, D.; Christianson, Andrew D.

      2015-12-15

      The structural and the magnetic properties of CeCu6-xAgx (0 ≤ x ≤ 0.85) and CeCu6-xPdx (0 ≤ x ≤ 0.4) have been studied using neutron diffraction, resonant ultrasound spectroscopy (RUS), x-ray diffraction measurements, and first principles calculations. The structural and magnetic phase diagrams of CeCu6-xAgx and CeCu6-xPdx as a function of Ag/Pd composition are reported. The end member, CeCu6, undergoes a structural phase transition from an orthorhombic (Pnma) to a monoclinic (P21/c) phase at 240 K. In CeCu6-xAgx, the structural phase transition temperature (Ts) decreases linearly with Ag concentration and extrapolates to zero at xS ≈ 0.1. The structural transition in CeCu6-xPdx remains unperturbed with Pd substitution within the range of our study. The lattice constant b slightly decreases with Ag/Pd doping, whereas a and c increase with an overall increase in the unit cell volume. Both systems, CeCu6-xAgx and CeCu6-xPdx, exhibit a magnetic quantum critical point (QCP), at x ≈ 0.2 and x ≈ 0.05, respectively. Near the QCP, long range antiferromagnetic ordering takes place at an incommensurate wave vector (δ1 0 δ2), where δ1 ~ 0.62, δ2 ~ 0.25, x = 0.125 for CeCu6-xPdx and δ1 ~ 0.64, δ2 ~ 0.3, x = 0.3 for CeCu6-xAgx. As a result, the magnetic structure consists of an amplitude modulation of the Ce moments which are aligned along the c axis of the orthorhombic unit cell.

    5. Structural and phase transition changes of sodium dodecyl sulfate micellar solution in alcohols probed by small-angle neutron scattering (SANS)

      SciTech Connect (OSTI)

      Putra, Edy Giri Rachman; Patriati, Arum

      2015-04-16

      Small-angle neutron scattering (SANS) measurements on 0.3M sodium dodecyl sulfate (SDS) micellar solutions have been performed in the presence of n-alcohols, from ethanol to decanol at different alcohol concentrations, 2–10 wt%. The ellipsoid micellar structure which occurred in the 0.3M SDS in aqueous solution with the size range of 30–50 Å has different behavior at various hydrocarbon chain length and concentration of alcohols. At low concentration and short chain-length of alcohols, such as ethanol, propanol, and butanol, the size of micelles reduced and had a spherical-like structure. The opposite effect occurred as medium to long chain alcohols, such as hexanol, octanol and decanol was added into the 0.3M SDS micellar solutions. The micelles structure changed to be more elongated in major axis and then crossed the critical phase transition from micellar solution into liquid crystal phase as lamellar structure emerged by further addition of alcohols. The inter-lamellar distances were also depending on the hydrocarbon chain length and concentration of alcohols. In the meantime, the persistent micellar structures occurred in addition of medium chain of n-alcohol, pentanol at all concentrations.

    6. Determination of structure and phase transition of light element nanocomposites in mesoporous silica: case study of NH3BH3 in MCM-41

      SciTech Connect (OSTI)

      Kim, Hyun Jeong; Karkamkar, Abhijeet J.; Autrey, Thomas; Chupas, Peter; Proffen, Thomas E.

      2009-09-30

      The structure of ammonia borane (AB), NH3BH3, infused in mesoporous silica MCM-41 and its evolution over the temperature range of 80 to 300 K was investigated using the atomic pair distribution function (PDF) analysis of synchrotron X-ray powder diffraction data in order to understand the origin of improved dehydrogenation properties of the system. Our study shows how X-ray PDF analysis can be used to elucidate the structure of light guest species loaded in mesoporous silica materials despite of its low scattering power of composed elements (N, B, and H) compared to its host (SiO2). PDF analyses of two AB-loaded compositions with weight ratio AB:MCM-41=1:1 and 3:1 provide a strong evidence that AB aggregate, previously found in AB:MCM-41?1:1 samples, is same species as neat AB. For both of them an orthorhombic to tetragonal structural phase transition occurs at 225 K on warming. On the other hand, AB residing inside meso-pores, which is found in AB:MCM-41=1:2 sample, does not undergo such phase transition. It rather stays in tetragonal phase over a wide temperature range of 110 to 240 K and starts to lose structural correlation above 240 K. This strongly suggests that nano-confinement of AB inside meso-pores stabilizes high temperature tetragonal phase at much lower temperature. These results provide important clues to two critical questions: why nan-compositions of AB leads dehydrogenation to lower temperature and why the neat AB like propoerties are recovered at high AB loading samples. This work was supported by the US Department of Energy Office of Basic Energy Sciences, Chemical Sciences program. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

    7. AC Transit

      Broader source: Energy.gov [DOE]

      AC Transit (or the Alameda-Contra Costa Transit District) is based in Oakland, California, and provides transportation services to the East Bay of San Francisco. The 360-square-mile service area includes 13 cities and adjacent unincorporated areas in Alameda and Contra Costa counties. AC Transit's approximately 638 vehicles serve more than 65 million annual passengers.

    8. Spatially resolved penetration depth measurements and vortex manipulation in the ferromagnetic superconductor ErNi2B2C

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

      Wulferding, Dirk; Yang, Ilkyu; Yang, Jinho; Lee, Minkyung; Choi, Hee Cheul; Bud'ko, Sergey L.; Canfield, Paul C.; Yeom, Han Woong; Kim, Jeehoon

      2015-07-31

      We present a local probe study of the magnetic superconductor ErNi2B2C, using magnetic force microscopy at sub-Kelvin temperatures. ErNi2B2C is an ideal system to explore the effects of concomitant superconductivity and ferromagnetism. At 500 mK, far below the transition to a weakly ferromagnetic state, we directly observe a structured magnetic background on the micrometer scale. We determine spatially resolved absolute values of the magnetic penetration depth λ and study its temperature dependence as the system undergoes magnetic phase transitions from paramagnetic to antiferromagnetic, and to weak ferromagnetic, all within the superconducting regime. We estimate the absolute pinning force of Abrikosovmore » vortices, which shows a position dependence and temperature dependence as well, and discuss the possibility of the purported spontaneous vortex formation.« less

    9. Pressure Effect on the Structural Transition and Suppression of the High-Spin State in the Triple-Layer T'-La₄Ni₃O₈

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

      Cheng, J.-G.; Zhou, J.-S.; Goodenough, J. B.; Zhou, H. D.; Matsubayashi, K.; Uwatoko, Y.; Kong, P. P.; Jin, C. Q.; Yang, W. G.; Shen, G. Y.

      2012-06-08

      We report a comprehensive high-pressure study on the triple-layer T'-La₄Ni₃O₈ with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at Pc≈6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T†-type structure, which involves a structural reconstruction from fluorite La–O₂–La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallicmore » phase under pressure has been discussed in terms of local displacements of O²⁻ ions in the fluorite block under pressure before a global T† phase is established.« less

    10. Pressure Effect on the Structural Transition and Suppression of the High-Spin State in the Triple-Layer T'-La?Ni?O?

      SciTech Connect (OSTI)

      Cheng, J.-G.; Zhou, J.-S.; Goodenough, J. B.; Zhou, H. D.; Matsubayashi, K.; Uwatoko, Y.; Kong, P. P.; Jin, C. Q.; Yang, W. G.; Shen, G. Y.

      2012-06-08

      We report a comprehensive high-pressure study on the triple-layer T'-La?Ni?O? with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at Pc?6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T-type structure, which involves a structural reconstruction from fluorite LaO?La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallic phase under pressure has been discussed in terms of local displacements of O? ions in the fluorite block under pressure before a global T phase is established.

    11. Structural characteristics of transition-iron-carbide precipitates formed during the first stage of tempering in 4340 steel

      SciTech Connect (OSTI)

      Thompson, S.W.

      2015-08-15

      Microstructural and crystallographic characteristics of fine-scale transition-iron-carbide precipitates formed in martensite during tempering of 4340 steel at 200 °C for 3.6 ks were studied via transmission electron microscopy. Precipitates of near-equiaxed shapes and about 10 nm in size were observed, and rows of closely spaced precipitates were aligned predominantly along < 100 > martensite directions. Aggregates of aligned precipitates were up to 150 nm in length, although occasional kinks were present that disrupted the alignment, and some of the adjacent precipitates possessed somewhat different crystallographic orientations. Electron-diffraction results were analyzed in detail and found to be consistent with both epsilon-carbide and eta-carbide phases. Similarities between these two phases were highlighted and discussed. Experimental electron-diffraction data were compared with data from five different unit cells, and each was found to be consistent within uncertainty ranges of ± 0.003 nm for interplanar spacings, ± 2° for angles between plane normals, and a few degrees for the orientation relationship between precipitates and the matrix.

    12. Property:Depth(m) | Open Energy Information

      Open Energy Info (EERE)

      Depth(m) Jump to: navigation, search This is a property of type String. Pages using the property "Depth(m)" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft...

    13. A conformational transition in the structure of a 2'-thiomethyl-modified DNA visualized at high resolution

      SciTech Connect (OSTI)

      Pallan, Pradeep S.; Prakash, Thazha P.; Li, Feng; Eoff, Robert L.; Manoharan, Muthiah; Egli, Martin

      2009-06-17

      Crystal structures of A-form and B-form DNA duplexes containing 2'-S-methyl-uridines reveal that the modified residues adopt a RNA-like C3'-endo pucker, illustrating that the replacement of electronegative oxygen at the 2'-carbon of RNA by sulfur does not appear to fundamentally alter the conformational preference of the sugar in the oligonucleotide context and sterics trump stereoelectronics.

    14. Uterine caliper and depth gauge

      DOE Patents [OSTI]

      King, Loyd L.; Wheeler, Robert G.; Fish, Thomas M.

      1977-01-01

      A uterine caliper and sound consisting of an elongated body having outwardly biased resilient caliper wings and a spring-loaded slidable cervical stop. A slide on the body is operatively connected to the wings by a monofilament and operates with respect to a first scale on the body as a width indicator. A rod extending longitudinally on the body is connected to the cervical stop and cooperates with a second scale on the body as a depth indicator. The instrument can be positioned to measure the distance from the outer cervical ostium to the fundus, as read on said second scale. The wings may be allowed to open by moving the slide, and when the wings engage the utero-tubal junctions, the width may be read on said first scale. By adjustment of the caliper wings the instrument may be retracted until the resistance of the inner ostium of the cervix is felt, enabling the length of the cervical canal to be read directly by the position of the longitudinal indicator rod with respect to said second scale. The instrument may be employed to measure the width of the uterine cavity at any position between the inner ostium of the cervix and the fundus.

    15. Structural phase transitions in Bi2Se3 under high pressure

      SciTech Connect (OSTI)

      Yu, Zhenhai; Gu, Genda; Wang, Lin; Hu, Qingyang; Zhao, Jinggeng; Yan, Shuai; Yang, Ke; Sinogeikin, Stanislav; Mao, Ho -kwang

      2015-11-02

      Raman spectroscopy and angle dispersive X-ray diffraction (XRD) experiments of bismuth selenide (Bi2Se3) have been carried out to pressures of 35.6 and 81.2 GPa, respectively, to explore its pressure-induced phase transformation. The experiments indicate that a progressive structural evolution occurs from an ambient rhombohedra phase (Space group (SG): R-3m) to monoclinic phase (SG: C2/m) and eventually to a high pressure body-centered tetragonal phase (SG: I4/mmm). Evidenced by our XRD data up to 81.2 GPa, the Bi2Se3 crystallizes into body-centered tetragonal structures rather than the recently reported disordered body-centered cubic (BCC) phase. Furthermore, first principles theoretical calculations favor the viewpoint that the I4/mmm phase Bi2Se3 can be stabilized under high pressure (>30 GPa). Remarkably, the Raman spectra of Bi2Se3 from this work (two independent runs) are still Raman active up to ~35 GPa. Furthermore, it is worthy to note that the disordered BCC phase at 27.8 GPa is not observed here. The remarkable difference in atomic radii of Bi and Se in Bi2Se3 may explain why Bi2Se3 shows different structural behavior than isocompounds Bi2Te3 and Sb2Te3.

    16. Surface structure determinations of crystalline ionic thin films grown on transition metal single crystal surfaces by low energy electron diffraction

      SciTech Connect (OSTI)

      Roberts, J.G.

      2000-05-01

      The surface structures of NaCl(100), LiF(100) and alpha-MgCl2(0001) adsorbed on various metal single crystals have been determined by low energy electron diffraction (LEED). Thin films of these salts were grown on metal substrates by exposing the heated metal surface to a molecular flux of salt emitted from a Knudsen cell. This method of investigating thin films of insulators (ionic salts) on a conducting substrate (metal) circumvents surface charging problems that plagued bulk studies, thereby allowing the use of electron-based techniques to characterize the surface.

    17. Fast radial flows in transition disk holes

      SciTech Connect (OSTI)

      Rosenfeld, Katherine A.; Andrews, Sean M.; Chiang, Eugene

      2014-02-20

      Protoplanetary 'transition' disks have large, mass-depleted central cavities, yet also deliver gas onto their host stars at rates comparable to disks without holes. The paradox of simultaneous transparency and accretion can be explained if gas flows inward at much higher radial speeds inside the cavity than outside the cavity, since surface density (and by extension optical depth) varies inversely with inflow velocity at fixed accretion rate. Radial speeds within the cavity might even have to approach free-fall values to explain the huge surface density contrasts inferred for transition disks. We identify observational diagnostics of fast radial inflow in channel maps made in optically thick spectral lines. Signatures include (1) twisted isophotes in maps made at low systemic velocities and (2) rotation of structures observed between maps made in high-velocity line wings. As a test case, we apply our new diagnostic tools to archival Atacama Large Millimeter Array data on the transition disk HD 142527 and uncover evidence for free-fall radial velocities inside its cavity. Although the observed kinematics are also consistent with a disk warp, the radial inflow scenario is preferred because it predicts low surface densities that appear consistent with recent observations of optically thin CO isotopologues in this disk. How material in the disk cavity sheds its angular momentum wholesale to fall freely onto the star is an unsolved problem; gravitational torques exerted by giant planets or brown dwarfs are briefly discussed as a candidate mechanism.

    18. Protective spin-labeled fluorenes maintain amyloid beta peptide in small oligomers and limit transitions in secondary structure

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

      Altman, Robin; Ly, Sonny; Hilt, Silvia; Petrlova, Jitka; Maezawa, Izumi; Kálai, Tamás; Hideg, Kálmán; Jin, Lee-Way; Laurence, Ted A.; Voss, John C.

      2015-12-01

      Alzheimer’s disease is characterized by the presence of extracellular plaques comprised of amyloid beta (Aβ) peptides. Soluble oligomers of the Aβ peptide underlie a cascade of neuronal loss and dysfunction associated with Alzheimer's disease. Single particle analyses of Aβ oligomers in solution by fluorescence correlation spectroscopy (FCS) were used to provide real-time descriptions of how spin-labeled fluorenes (SLFs; bi-functional small molecules that block the toxicity of Aβ) prevent and disrupt oligomeric assemblies of Aβ in solution. The FCS results, combined with electron paramagnetic resonance spectroscopy and circular dichroism spectroscopy, demonstrate SLFs can inhibit the growth of Aβ oligomers and disruptmore » existing oligomers while retaining Aβ in a largely disordered state. Furthermore, while the ability of SLF to block Aβ toxicity correlates with a reduction in oligomer size, our results suggest the conformation of Aβ within the oligomer determines the toxicity of the species. Attenuation of Aβ toxicity, which has been associated primarily with the soluble oligomeric form, can be achieved through redistribution of the peptides into smaller oligomers and arrest of the fractional increase in beta secondary structure.« less

    19. Intrinsic relationship between electronic structures and phase transition of SrBi{sub 2?x}Nd{sub x}Nb{sub 2}O{sub 9} ceramics from ultraviolet ellipsometry at elevated temperatures

      SciTech Connect (OSTI)

      Duan, Z. H.; Jiang, K.; Xu, L. P.; Li, Y. W.; Hu, Z. G. Chu, J. H.

      2014-02-07

      The ferroelectric orthorhombic to paraelectric tetragonal phase transition of SrBi{sub 2?x}Nd{sub x}Nb{sub 2}O{sub 9} (x?=?0, 0.05, 0.1, and 0.2) layer-structured ceramics has been investigated by temperature-dependent spectroscopic ellipsometry. Based on the analysis of dielectric functions from 0 to 500?C with double Tauc-Lorentz dispersion model, the interband transitions located at ultraviolet region have shown an abrupt variation near the Curie temperature. The changes of dielectric functions are mainly due to the thermal-optical and/or photoelastic effect. Moreover, the characteristic alteration in interband transitions can be ascribed to distortion of NbO{sub 6} octahedron and variation of hybridization between Bi 6s and O 2p states during the structure transformation.

    20. Two Keggin-type heteropolytungstates with transition metal as a central atom: Crystal structure and magnetic study with 2D-IR correlation spectroscopy

      SciTech Connect (OSTI)

      Chai, Feng [Department of Chemistry, Fuzhou University, Fuzhou 350108 (China); Chen, YiPing, E-mail: ypchen007@sina.com [Department of Chemistry, Fuzhou University, Fuzhou 350108 (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); You, ZhuChai; Xia, ZeMin; Ge, SuZhi; Sun, YanQiong; Huang, BiHua [Department of Chemistry, Fuzhou University, Fuzhou 350108 (China)

      2013-06-01

      Two Keggin-type heteropolytungstates, [Co(phen)?]?[CoW??O??]9H?O 1 (phen=1,10-phenanthroline) and [Fe(phen)?]?[FeW??O??]H?OH?O 2, have been synthesized via the hydrothermal technique and characterized by single crystal X-ray diffraction analyses, IR, XPS, TG analysis, UVDRS, XRD, thermal-dependent and magnetic-dependent 2D-COS IR (two-dimensional infrared correlation spectroscopy). Crystal structure analysis reveals that the polyanions in compound 1 are linked into 3D supramolecule through hydrogen bonding interactions between lattice water molecules and terminal oxygen atoms of polyanion units, and [Co(phen)?]? cations distributed in the polyanion framework with many hydrogen bonding interactions. The XPS spectra indicate that all the Co atoms in 1 are +2 oxidation state, the Fe atoms in 2 existing with +2 and +3 mixed oxidation states. - Graphical abstract: The magnetic-dependent synchronous 2D correlation IR spectra of 1 (a), 2 (b) over 050 mT in the range of 6001000 cm?, the obvious response indicate two Keggin polyanions skeleton susceptible to applied magnetic field. Highlights: Two Keggin-type heteropolytungstates with transition metal as a central atom has been obtained. Compound 1 forms into 3D supramolecular architecture through hydrogen bonding between water molecules and polyanions. Magnetic-dependent 2D-IR correlation spectroscopy was introduced to discuss the magnetism of polyoxometalate.

    1. Matter in transition

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

      Anderson, Lara B.; Gray, James; Raghuram, Nikhil; Taylor, Washington

      2016-04-13

      In this study, we explore a novel type of transition in certain 6D and 4D quantum field theories, in which the matter content of the theory changes while the gauge group and other parts of the spectrum remain invariant. Such transitions can occur, for example, for SU(6) and SU(7) gauge groups, where matter fields in a three-index antisymmetric representation and the fundamental representation are exchanged in the transition for matter in the two-index antisymmetric representation. These matter transitions are realized by passing through superconformal theories at the transition point. We explore these transitions in dual F-theory and heterotic descriptions, wheremore » a number of novel features arise. For example, in the heterotic description the relevant 6D SU(7) theories are described by bundles on K3 surfaces where the geometry of the K3 is constrained in addition to the bundle structure. On the F-theory side, non-standard representations such as the three-index antisymmetric representation of SU(N) require Weierstrass models that cannot be realized from the standard SU(N) Tate form. We also briefly describe some other situations, with groups such as Sp(3), SO(12), and SU(3), where analogous matter transitions can occur between different representations. For SU(3), in particular, we find a matter transition between adjoint matter and matter in the symmetric representation, giving an explicit Weierstrass model for the F-theory description of the symmetric representation that complements another recent analogous construction.« less

    2. Control of electrode depth in electroslag remelting

      DOE Patents [OSTI]

      Melgaard, David K.; Shelmidine, Gregory J.; Damkroger, Brian K.

      2002-01-01

      A method of and apparatus for controlling an electroslag remelting furnace by driving the electrode at a nominal speed based upon melting rate and geometry while making minor proportional adjustments based on a measured metric of the electrode immersion depth. Electrode drive speed is increased if a measured metric of electrode immersion depth differs from a set point by a predetermined amount, indicating that the tip is too close to the surface of a slag pool. Impedance spikes are monitored to adjust the set point for the metric of electrode immersion depth based upon one or more properties of the impedance spikes.

    3. VARIABILITY OF DISK EMISSION IN PRE-MAIN SEQUENCE AND RELATED STARS. III. EXPLORING STRUCTURAL CHANGES IN THE PRE-TRANSITIONAL DISK IN HD169142

      SciTech Connect (OSTI)

      Wagner, Kevin R.; Sitko, Michael L.; Swearingen, Jeremy R.; Champney, Elizabeth H.; Johnson, Alexa N.; Werren, Chelsea; Grady, Carol A.; Whitney, Barbara A.; Russell, Ray W.; Schneider, Glenn H.; Momose, Munetake; Muto, Takayuki; Inoue, Akio K.; Lauroesch, James T.; Hornbeck, Jeremy; Brown, Alexander; Fukagawa, Misato; Currie, Thayne M.; Wisniewski, John P.; Woodgate, Bruce E. E-mail: sitkoml@ucmail.uc.edu E-mail: ehchampney@gmail.com E-mail: ccwerren@yahoo.com E-mail: bwhitney@astro.wisc.edu

      2015-01-10

      We present near-IR (NIR) and far-UV observations of the pre-transitional (gapped) disk in HD169142 using NASA's Infrared Telescope Facility and Hubble Space Telescope. The combination of our data along with existing data sets into the broadband spectral energy distribution reveals variability of up to 45% between ?1.5-10 ?m over a maximum timescale of 10yr. All observations known to us separate into two distinct states corresponding to a high near-IR state in the pre-2000 epoch and a low state in the post-2000 epoch, indicating activity within the ?1 AU region of the disk. Through analysis of the Pa ? and Br ? lines in our data we derive a mass accretion rate in 2013 May of M-dot ? (1.5-2.7) 10{sup 9} M {sub ?} yr{sup 1}. We present a theoretical modeling analysis of the disk in HD169142 using Monte-Carlo radiative transfer simulation software to explore the conditions and perhaps signs of planetary formation in our collection of 24yr of observations. We find that shifting the outer edge (r ? 0.3 AU) of the inner disk by 0.05 AU toward the star (in simulation of accretion and/or sculpting by forming planets) successfully reproduces the shift in NIR flux. We establish that the ?40-70 AU dark ring imaged in the NIR by Quanz et al. and Momose et al. and at 7mm by Osorio et al. may be reproduced with a 30% scaled density profile throughout the region, strengthening the link to this structure being dynamically cleared by one or more planetary mass bodies.

    4. Depth-dependent phase change in Gd{sub 2}O{sub 3} epitaxial layers under ion irradiation

      SciTech Connect (OSTI)

      Mejai, N.; Debelle, A. Thomé, L.; Sattonnay, G.; Gosset, D.; Dargis, R.; Clark, A.

      2015-09-28

      Epitaxial Gd{sub 2}O{sub 3} thin layers with the cubic structure were irradiated with 4-MeV Au{sup 2+} ions in the 10{sup 13}–10{sup 15} cm{sup −2} fluence range. X-ray diffraction indicates that ion irradiation induces a cubic to monoclinic phase change. Strikingly, although the energy-deposition profile of the Au{sup 2+} ions is constant over the layer thickness, this phase transformation is depth-dependent, as revealed by a combined X-ray diffraction and ion channeling analysis. In fact, the transition initiates very close to the surface and propagates inwards, which can be explained by an assisted migration process of irradiation-induced defects. This result is promising for developing a method to control the thickness of the rare-earth oxide crystalline phases.

    5. TRENDS IN ESTIMATED MIXING DEPTH DAILY MAXIMUMS

      SciTech Connect (OSTI)

      Buckley, R; Amy DuPont, A; Robert Kurzeja, R; Matt Parker, M

      2007-11-12

      Mixing depth is an important quantity in the determination of air pollution concentrations. Fireweather forecasts depend strongly on estimates of the mixing depth as a means of determining the altitude and dilution (ventilation rates) of smoke plumes. The Savannah River United States Forest Service (USFS) routinely conducts prescribed fires at the Savannah River Site (SRS), a heavily wooded Department of Energy (DOE) facility located in southwest South Carolina. For many years, the Savannah River National Laboratory (SRNL) has provided forecasts of weather conditions in support of the fire program, including an estimated mixing depth using potential temperature and turbulence change with height at a given location. This paper examines trends in the average estimated mixing depth daily maximum at the SRS over an extended period of time (4.75 years) derived from numerical atmospheric simulations using two versions of the Regional Atmospheric Modeling System (RAMS). This allows for differences to be seen between the model versions, as well as trends on a multi-year time frame. In addition, comparisons of predicted mixing depth for individual days in which special balloon soundings were released are also discussed.

    6. Structural phase transition, narrow band gap, and room-temperature ferromagnetism in [KNbO{sub 3}]{sub 1?x}[BaNi{sub 1/2}Nb{sub 1/2}O{sub 3??}]{sub x} ferroelectrics

      SciTech Connect (OSTI)

      Zhou, Wenliang; Yang, Pingxiong Chu, Junhao; Deng, Hongmei

      2014-09-15

      Structural phase transition, narrow band gap (E{sub g}), and room-temperature ferromagnetism (RTFM) have been observed in the [KNbO{sub 3}]{sub 1?x}[BaNi{sub 1/2}Nb{sub 1/2}O{sub 3??}]{sub x} (KBNNO) ceramics. All the samples have single phase perovskite structure, but exhibit a gradual transition behaviour from the orthorhombic to a cubic structure with the increase of x. Raman spectroscopy analysis not only corroborates this doping-induced change in normal structure but also shows the local crystal symmetry for x ? 0.1 compositions to deviate from the idealized cubic perovskite structure. A possible mechanism for the observed specific changes in lattice structure is discussed. Moreover, it is noted that KBNNO with compositions x?=?0.10.3 have quite narrow E{sub g} of below 1.5?eV, much smaller than the 3.2?eV band gap of parent KNbO{sub 3} (KNO), which is due to the increasing Ni 3d electronic states within the gap of KNO. Furthermore, the KBNNO materials present RTFM near a tetragonal to cubic phase boundary. With increasing x from 0 to 0.3, the magnetism of the samples develops from diamagnetism to ferromagnetism and paramagnetism, originating from the ferromagneticantiferromagnetic competition. These results are helpful in the deeper understanding of phase transitions, band gap tunability, and magnetism variations in perovskite oxides and show the potential role, such materials can play, in perovskite solar cells and multiferroic applications.

    7. ARM - PI Product - Niamey Aerosol Optical Depths

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

      Aerosol Optical Depths ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Niamey Aerosol Optical Depths MFRSR irradiance data collected during the ACRF AMF deployment in Niamey, Niger have been used to derive AOD for five wavelength channels of the MFRSR. These data have been corrected to adjust for filter drift over the course of the campaign and contamination due to forward scattering as a result of

    8. Development of Site Transition Plan, Use of the Site Transition...

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

      Site Transition Plan, Use of the Site Transition Framework, and Terms and Conditions for Site Transition Development of Site Transition Plan, Use of the Site Transition Framework, ...

    9. Defense-in-Depth, How Department of Energy Implements Radiation...

      Energy Savers [EERE]

      Defense-in-Depth, How Department of Energy Implements Radiation Protection in Low Level Waste Disposal Defense-in-Depth, How Department of Energy Implements Radiation Protection in ...

    10. Structural phase transition of ternary dielectric SmGdO{sub 3}: Evidence from angle dispersive x-ray diffraction and Raman spectroscopic studies

      SciTech Connect (OSTI)

      Sharma, Yogesh E-mail: satya504@gmail.com Sahoo, Satyaprakash E-mail: satya504@gmail.com Misra, Pankaj; Pavunny, Shojan P.; Katiyar, Ram S. E-mail: satya504@gmail.com; Mishra, A. K.; Dwivedi, Abhilash; Sharma, S. M.

      2015-03-07

      High-pressure synchrotron based angle dispersive x-ray diffraction (ADXRD) studies were carried out on SmGdO{sub 3} (SGO) up to 25.7 GPa at room temperature. ADXRD results indicated a reversible pressure-induced phase transition from ambient monoclinic to hexagonal phase at ∼8.9 GPa. The observed pressure-volume data were fitted with the third order Birch-Murnaghan equation of state yielding zero pressure bulk modulus B{sub 0} = 132(22) and 177(9) GPa for monoclinic (B-type) and hexagonal (A-type) phases, respectively. Pressure dependent micro-Raman spectroscopy further confirmed the monoclinic to hexagonal phase transition at about 5.24 GPa. The mode Grüneisen parameters and pressure coefficients for different Raman modes corresponding to each individual phases of SGO were calculated using pressure dependent Raman mode analysis.

    11. Hyperfine structure of {sup 87,89}Sr 5s4d{sup 3}D-5snf transitions in collinear fast beam RIMS

      SciTech Connect (OSTI)

      Bushaw, B. A.; Kluge, H.-J.; Lantzsch, J.; Schwalbach, R.; Schwarz, M.; Stenner, J.; Stevens, H.; Wendt, K.; Zimmer, K.

      1995-04-01

      The title transition, with n=20, 23, and 32 were measured for stable {sup 87}Sr and the observed hfs was interpreted and strong hyperfine mixing of all four terms {sup 1}F3 and {sup 3}F2,3,4 in the upper configuration. The results of the analysis were used to predict the hfs for the radioactive isotope {sup 89}Sr. Measurement were then performed on samples containing 10{sup 9} atoms {sup 89}Sr. The positions and intensities of the hfs components selected for study were found to agree well with the predicted values.

    12. Campbell penetration depth in Fe-based superconductors

      SciTech Connect (OSTI)

      Prommapan, Plegchart

      2011-08-15

      A 'true' critical current density, j{sub c}, as opposite to commonly measured relaxed persistent (Bean) current, j{sub B}, was extracted from the Campbell penetration depth, {lambda}{sub c}(T,H) measured in single crystals of LiFeAs, and optimally electron-doped Ba(Fe{sub 0.954}Ni{sub 0.046}){sub 2}As{sub 2} (FeNi122). In LiFeAs, the effective pinning potential is nonparabolic, which follows from the magnetic field - dependent Labusch parameter {alpha}. At the equilibrium (upon field - cooling), {alpha}(H) is non-monotonic, but it is monotonic at a finite gradient of the vortex density. This behavior leads to a faster magnetic relaxation at the lower fields and provides a natural dynamic explanation for the fishtail (second peak) effect. We also find the evidence for strong pinning at the lower fields.The inferred field dependence of the pinning potential is consistent with the evolution from strong pinning, through collective pinning, and eventually to a disordered vortex lattice. The value of j{sub c}(2 K) {approx_equal} 1.22 x 10{sup 6} A/cm{sup 2} provide an upper estimate of the current carrying capability of LiFeAs. Overall, vortex behavior of almost isotropic, fully-gapped LiFeAs is very similar to highly anisotropic d-wave cuprate superconductors, the similarity that requires further studies in order to understand unconventional superconductivity in cuprates and pnictides. In addition to LiFeAs, we also report the magnetic penetration depth in BaFe{sub 2}As{sub 2} based superconductors including irradiation of FeNi122. In unirradiated FeNi122, the maximum critical current value is, j{sub c}(2K) {approx_equal} 3.3 x 10{sup 6} A/cm{sup 2}. The magnetic-dependent feature was observed near the transition temperature in FeTe{sub 0.53}Se{sub 0.47} and irradiated FeNi122. Because of this feature, further studies are required in order to properly calibrate the Campbell penetration depth. Finally, we detected the crossing between the magnetic penetration depth and

    13. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second...

      Energy Savers [EERE]

      Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and ...

    14. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third...

      Energy Savers [EERE]

      Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation Report and Appendices Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation Report and ...

    15. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary...

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

      Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results This ...

    16. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell...

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

      Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation Report and ...

    17. Alameda-Contra Costa Transit District Fuel Cell Transit Buses...

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

      SunLine Transit Agency Hydrogen-Powered Transit Buses: Evaluation Results Update Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices

    18. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell...

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

      Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and ... Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation Report and Appendices

    19. Effective Incentive Structures

      Broader source: Energy.gov [DOE]

      Presents an in-depth look at effective incentive structures, how to clarify your program goals, and tips to plan for the long term.

    20. Atomistic tight-binding study of electronic structure and interband optical transitions in GaBi{sub x}As{sub 1?x}/GaAs quantum wells

      SciTech Connect (OSTI)

      Usman, Muhammad; O'Reilly, Eoin P.

      2014-02-17

      Large-supercell tight-binding calculations are presented for GaBi{sub x}As{sub 1?x}/GaAs single quantum wells (QWs) with Bi fractions x of 3.125% and 12.5%. Our results highlight significant distortion of the valence band states due to the alloy disorder. A large full-width-half-maximum (FWHM) is estimated in the ground state interband transition energy (?33?meV) at 3.125% Bi, consistent with recent photovoltage measurements for similar Bi compositions. Additionally, the alloy disorder effects are predicted to become more pronounced as the QW width is increased. However, they are less strong at the higher Bi composition (12.5%) required for the design of temperature-stable lasers, with a calculated FWHM of ?23.5?meV at x?=?12.5%.

    1. Analysis of Nuclear Quantum Phase Transitions

      SciTech Connect (OSTI)

      Li, Z. P.; Meng, J.; Niksic, T.; Vretenar, D.; Lalazissis, G. A.; Ring, P.

      2009-08-26

      A microscopic analysis, based on nuclear energy density functionals, is presented for shape phase transitions in Nd isotopes. Low-lying excitation spectra and transition probabilities are calculated starting from a five-dimensional Hamiltonian, with parameters determined by constrained relativistic mean-field calculations for triaxial shapes. The results reproduce available data, and show that there is an abrupt change of structure at N = 90, that corresponds to a first-order quantum phase transition between spherical and axially deformed shapes.

    2. Identification Of Rippability And Bedrock Depth Using Seismic Refraction

      SciTech Connect (OSTI)

      Ismail, Nur Azwin; Saad, Rosli; Nawawi, M. N. M; Muztaza, Nordiana Mohd; El Hidayah Ismail, Noer; Mohamad, Edy Tonizam

      2010-12-23

      Spatial variability of the bedrock with reference to the ground surface is vital for many applications in geotechnical engineering to decide the type of foundation of a structure. A study was done within the development area of Mutiara Damansara utilising the seismic refraction method using ABEM MK8 24 channel seismograph. The geological features of the subsurface were investigated and velocities, depth to the underlying layers were determined. The seismic velocities were correlated with rippability characteristics and borehole records. Seismic sections generally show a three layer case. The first layer with velocity 400-600 m/s predominantly consists of soil mix with gravel. The second layer with velocity 1600-2000 m/s is suggested to be saturated and weathered area. Both layers forms an overburden and generally rippable. The third layer represents granite bedrock with average depth and velocity 10-30 m and >3000 m/s respectively and it is non-rippable. Steep slope on the bedrock are probably the results of shear zones.

    3. Abnormal thermal expansion, multiple transitions, magnetocaloric effect, and electronic structure of Gd{sub 6}Co{sub 4.85}

      SciTech Connect (OSTI)

      Zhang, Jiliang; Zheng, Zhigang; Shan, Guangcun E-mail: bobev@udel.edu; Bobev, Svilen E-mail: bobev@udel.edu; Shek, Chan Hung E-mail: bobev@udel.edu

      2015-10-07

      The structure of known Gd{sub 4}Co{sub 3} compound is re-determined as Gd{sub 6}Co{sub 4.85}, adopting the Gd{sub 6}Co{sub 1.67}Si{sub 3} structure type, which is characterized by two disorder Co sites filling the Gd octahedral and a short Gd-Gd distance within the octahedra. The compound shows uniaxial negative thermal expansion in paramagnetic state, significant negative expansion in ferromagnetic state, and positive expansion below ca. 140 K. It also exhibits large magnetocaloric effect, with an entropy change of −6.4 J kg{sup −1} K{sup −1} at 50 kOe. In the lattice of the compound, Co atoms at different sites show different spin states. It was confirmed by the X-ray photoelectron spectra and calculation of electronic structure and shed lights on the abnormal thermal expansion. The stability of such compound and the origin of its magnetism are also discussed based on measured and calculated electronic structures.

    4. Gulf of Mexico Proved Reserves By Water Depth, 2009

      Gasoline and Diesel Fuel Update (EIA)

      Gulf of Mexico Proved Reserves and Production by Water Depth, 2009 1 Gulf of Mexico Proved Reserves and Production by Water Depth The Gulf of Mexico Federal Offshore region (GOM ...

    5. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell...

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

      Transit Bus: Fifth Evaluation Report SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation Report and Appendices SunLine Transit Agency Fuel Cell Transit Bus: ...

    6. Hyperspectral Aerosol Optical Depths from TCAP Flights

      SciTech Connect (OSTI)

      Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

      2013-11-13

      4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the worlds first hyperspectral airborne tracking sunphotometer, acquired aerosol optical depths (AOD) at 1 Hz during all July 2012 flights of the Two Column Aerosol Project (TCAP). Root-mean square differences from AERONET ground-based observations were 0.01 at wavelengths between 500-1020 nm, 0.02 at 380 and 1640 nm and 0.03 at 440 nm in four clear-sky fly-over events, and similar in ground side-by-side comparisons. Changes in the above-aircraft AOD across 3-km-deep spirals were typically consistent with integrals of coincident in situ (on DOE Gulfstream 1 with 4STAR) and lidar (on NASA B200) extinction measurements within 0.01, 0.03, 0.01, 0.02, 0.02, 0.02 at 355, 450, 532, 550, 700, 1064 nm, respectively, despite atmospheric variations and combined measurement uncertainties. Finer vertical differentials of the 4STAR measurements matched the in situ ambient extinction profile within 14% for one homogeneous column. For the AOD observed between 350-1660 nm, excluding strong water vapor and oxygen absorption bands, estimated uncertainties were ~0.01 and dominated by (then) unpredictable throughput changes, up to +/-0.8%, of the fiber optic rotary joint. The favorable intercomparisons herald 4STARs spatially-resolved high-frequency hyperspectral products as a reliable tool for climate studies and satellite validation.

    7. Exploration of R2XM2 (R=Sc, Y, Ti, Zr, Hf, rare earth; X=main group element; M=transition metal, Si, Ge): Structural Motifs, the novel Compound Gd2AlGe2 and Analysis of the U3Si2 and Zr3Al2 Structure Types

      SciTech Connect (OSTI)

      Sean William McWhorter

      2006-05-01

      In the process of exploring and understanding the influence of crystal structure on the system of compounds with the composition Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} several new compounds were synthesized with different crystal structures, but similar structural features. In Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4}, the main feature of interest is the magnetocaloric effect (MCE), which allows the material to be useful in magnetic refrigeration applications. The MCE is based on the magnetic interactions of the Gd atoms in the crystal structure, which varies with x (the amount of Si in the compound). The crystal structure of Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} can be thought of as being formed from two 3{sup 2}434 nets of Gd atoms, with additional Gd atoms in the cubic voids and Si/Ge atoms in the trigonal prismatic voids. Attempts were made to substitute nonmagnetic atoms for magnetic Gd using In, Mg and Al. Gd{sub 2}MgGe{sub 2} and Gd{sub 2}InGe{sub 2} both possess the same 3{sup 2}434 nets of Gd atoms as Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4}, but these nets are connected differently, forming the Mo{sub 2}FeB{sub 2} crystal structure. A search of the literature revealed that compounds with the composition R{sub 2}XM{sub 2} (R=Sc, Y, Ti, Zr, Hf, rare earth; X=main group element; M=transition metal, Si, Ge) crystallize in one of four crystal structures: the Mo{sub 2}FeB{sub 2}, Zr{sub 3}Al{sub 2}, Mn{sub 2}AlB{sub 2} and W{sub 2}CoB{sub 2} crystal structures. These crystal structures are described, and the relationships between them are highlighted. Gd{sub 2}AlGe{sub 2} forms an entirely new crystal structure, and the details of its synthesis and characterization are given. Electronic structure calculations are performed to understand the nature of bonding in this compound and how electrons can be accounted for. A series of electronic structure calculations were performed on models with the U{sub 3}Si{sub 2} and Zr{sub 3}Al{sub 2} structures, using Zr and A1 as

    8. Transition section for acoustic waveguides

      DOE Patents [OSTI]

      Karplus, H.H.B.

      1975-10-28

      A means of facilitating the transmission of acoustic waves with minimal reflection between two regions having different specific acoustic impedances is described comprising a region exhibiting a constant product of cross-sectional area and specific acoustic impedance at each cross-sectional plane along the axis of the transition region. A variety of structures that exhibit this feature is disclosed, the preferred embodiment comprising a nested structure of doubly reentrant cones. This structure is useful for monitoring the operation of nuclear reactors in which random acoustic signals are generated in the course of operation.

    9. Optical and structural characterization of nitrogen-rich InN: Transition from nearly intrinsic to strongly n-type degenerate with temperature

      SciTech Connect (OSTI)

      Hong Tran, Nhung; Huy Le, Binh; Fan, Shizhao; Zhao, Songrui; Mi, Zetian; Schmidt, Benjamin A.; Savard, Michel; Gervais, Guillaume; Butcher, Kenneth Scott A.

      2013-12-23

      We report on a detailed study of the structural and optical properties of nonstoichiometric nitrogen-rich InN grown on sapphire substrates, by migration enhanced afterglow deposition. The samples were polycrystalline, with the presence of InN dots. Unusually strong photoluminescence emission was measured at cryogenic temperatures, with the peak energy at ?0.68?eV. Detailed analysis further shows that the sample has very low residual electron density in the range of ?10{sup 16}?cm{sup ?3} at temperatures below 20?K.

    10. Exoplanet transit spectroscopy using WFC3: WASP-12 b, WASP-17 b, and WASP-19 b

      SciTech Connect (OSTI)

      Mandell, Avi M.; Haynes, Korey; Sinukoff, Evan; Madhusudhan, Nikku; Burrows, Adam; Deming, Drake

      2013-12-20

      We report an analysis of transit spectroscopy of the extrasolar planets WASP-12 b, WASP-17 b, and WASP-19 b using the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). We analyze the data for a single transit for each planet using a strategy similar, in certain aspects, to the techniques used by Berta et al., but we extend their methodology to allow us to correct for channel- or wavelength-dependent instrumental effects by utilizing the band-integrated time series and measurements of the drift of the spectrum on the detector over time. We achieve almost photon-limited results for individual spectral bins, but the uncertainties in the transit depth for the band-integrated data are exacerbated by the uneven sampling of the light curve imposed by the orbital phasing of HST's observations. Our final transit spectra for all three objects are consistent with the presence of a broad absorption feature at 1.4 ?m most likely due to water. However, the amplitude of the absorption is less than that expected based on previous observations with Spitzer, possibly due to hazes absorbing in the NIR or non-solar compositions. The degeneracy of models with different compositions and temperature structures combined with the low amplitude of any features in the data preclude our ability to place unambiguous constraints on the atmospheric composition without additional observations with WFC3 to improve the signal-to-noise ratio and/or a comprehensive multi-wavelength analysis.

    11. Rooting depths of plants relative to biological and environmental factors

      SciTech Connect (OSTI)

      Foxx, T S; Tierney, G D; Williams, J M

      1984-11-01

      In 1981 to 1982 an extensive bibliographic study was completed to document rooting depths of native plants in the United States. The data base presently contains 1034 citations with approximately 12,000 data elements. In this paper the data were analyzed for rooting depths as related to life form, soil type, geographical region, root type, family, root depth to shoot height ratios, and root depth to root lateral ratios. Average rooting depth and rooting frequencies were determined and related to present low-level waste site maintenance.

    12. Gas turbine combustor transition

      DOE Patents [OSTI]

      Coslow, Billy Joe; Whidden, Graydon Lane

      1999-01-01

      A method of converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit.

    13. Gas turbine combustor transition

      DOE Patents [OSTI]

      Coslow, B.J.; Whidden, G.L.

      1999-05-25

      A method is described for converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit. 7 figs.

    14. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation

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

      Report and Appendices | Department of Energy 2.pdf (1.02 MB) More Documents & Publications Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Third Evaluation Report - Appendices Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    15. Supersaturating silicon with transition metals by ion implantation and pulsed laser melting

      SciTech Connect (OSTI)

      Recht, Daniel; Aziz, Michael J.; Smith, Matthew J.; Grade?ak, Silvija; Charnvanichborikarn, Supakit; Williams, James S.; Sullivan, Joseph T.; Winkler, Mark T.; Buonassisi, Tonio; Mathews, Jay; Warrender, Jeffrey M.

      2013-09-28

      We investigate the possibility of creating an intermediate band semiconductor by supersaturating Si with a range of transition metals (Au, Co, Cr, Cu, Fe, Pd, Pt, W, and Zn) using ion implantation followed by pulsed laser melting (PLM). Structural characterization shows evidence of either surface segregation or cellular breakdown in all transition metals investigated, preventing the formation of high supersaturations. However, concentration-depth profiling reveals that regions of Si supersaturated with Au and Zn are formed below the regions of cellular breakdown. Fits to the concentration-depth profile are used to estimate the diffusive speeds, v{sub D,} of Au and Zn, and put lower bounds on v{sub D} of the other metals ranging from 10{sup 2} to 10{sup 4} m/s. Knowledge of v{sub D} is used to tailor the irradiation conditions and synthesize single-crystal Si supersaturated with 10{sup 19} Au/cm{sup 3} without cellular breakdown. Values of v{sub D} are compared to those for other elements in Si. Two independent thermophysical properties, the solute diffusivity at the melting temperature, D{sub s}(T{sub m}), and the equilibrium partition coefficient, k{sub e}, are shown to simultaneously affect v{sub D}. We demonstrate a correlation between v{sub D} and the ratio D{sub s}(T{sub m})/k{sub e}{sup 0.67}, which is exhibited for Group III, IV, and V solutes but not for the transition metals investigated. Nevertheless, comparison with experimental results suggests that D{sub s}(T{sub m})/k{sub e}{sup 0.67} might serve as a metric for evaluating the potential to supersaturate Si with transition metals by PLM.

    16. APOSTLE: 11 TRANSIT OBSERVATIONS OF TrES-3b

      SciTech Connect (OSTI)

      Kundurthy, P.; Becker, A. C.; Agol, E.; Barnes, R.; Williams, B.

      2013-02-10

      The Apache Point Survey of Transit Lightcurves of Exoplanets (APOSTLE) observed 11 transits of TrES-3b over two years in order to constrain system parameters and look for transit timing and depth variations. We describe an updated analysis protocol for APOSTLE data, including the reduction pipeline, transit model, and Markov Chain Monte Carlo analyzer. Our estimates of the system parameters for TrES-3b are consistent with previous estimates to within the 2{sigma} confidence level. We improved the errors (by 10%-30%) on system parameters such as the orbital inclination (i {sub orb}), impact parameter (b), and stellar density ({rho}{sub *}) compared to previous measurements. The near-grazing nature of the system, and incomplete sampling of some transits, limited our ability to place reliable uncertainties on individual transit depths and hence we do not report strong evidence for variability. Our analysis of the transit timing data shows no evidence for transit timing variations and our timing measurements are able to rule out super-Earth and gas giant companions in low-order mean motion resonance with TrES-3b.

    17. The A-site driven phase transition procedure of (Pb{sub 0.97}La{sub 0.02})(Zr{sub 0.42}Sn{sub 0.40}Ti{sub 0.18})O{sub 3} ceramics: An evidence from electronic structure variation

      SciTech Connect (OSTI)

      Chen, X.; Jiang, P. P; Duan, Z. H.; Hu, Z. G. Chu, J. H.; Chen, X. F.; Wang, G. S.; Dong, X. L.

      2013-11-04

      The transition of (Pb{sub 0.97}La{sub 0.02})(Zr{sub 0.42}Sn{sub 0.40}Ti{sub 0.18})O{sub 3} (PLZST) ceramic has been investigated by temperature-dependent X-ray diffraction (XRD) and spectroscopic ellipsometry (SE). The rhombohedral and tetragonal symmetries are confirmed by XRD analysis. Two interband transitions (E{sub cp1} and E{sub cp2}) located at about 3.7 and 5.2?eV can be derived from the second derivative of the complex dielectric functions using the standard critical point (SCP) model. Except for the negative temperature coefficient parts, the transitions present additional parts corresponding to appearance of the antiferroelectric (AFE) phase. The phenomena can be attributed to variation of the electronic structure during A-site driven phase transition.

    18. Method and apparatus of prefetching streams of varying prefetch depth

      DOE Patents [OSTI]

      Gara, Alan; Ohmacht, Martin; Salapura, Valentina; Sugavanam, Krishnan; Hoenicke, Dirk

      2012-01-24

      Method and apparatus of prefetching streams of varying prefetch depth dynamically changes the depth of prefetching so that the number of multiple streams as well as the hit rate of a single stream are optimized. The method and apparatus in one aspect monitor a plurality of load requests from a processing unit for data in a prefetch buffer, determine an access pattern associated with the plurality of load requests and adjust a prefetch depth according to the access pattern.

    19. Control Systems Cyber Security: Defense in Depth Strategies ...

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

      Cyber Security: Defense in Depth Strategies Control Systems Cyber Security: Defense in ... strategies for organizations that use control system networks while maintaining a ...

    20. Bouguer gravity anomalies, depth to bedrock, and shallow temperature...

      Open Energy Info (EERE)

      Bouguer gravity anomalies, depth to bedrock, and shallow temperature in the Humboldt House geothermal area, Pershing County, Nevada Jump to: navigation, search OpenEI Reference...

    1. Hyperspectral aerosol optical depths from TCAP flights (Journal...

      Office of Scientific and Technical Information (OSTI)

      Journal Article: Hyperspectral aerosol optical depths from TCAP flights Citation Details ... DOE Contract Number: DE-AC02-98CH10886 Resource Type: Journal Article Resource Relation: ...

    2. ARM - Evaluation Product - MicroPulse LIDAR Cloud Optical Depth...

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

      from the MPLNOR (Micro Pulse Lidar Normalized Backscatter) and radiosonde thermodynamic profiles. The optical depth retrieval is derived following Comstock et al. (2001),...

    3. Understanding Fault Characteristics And Sediment Depth For Geothermal...

      Open Energy Info (EERE)

      Understanding Fault Characteristics And Sediment Depth For Geothermal Exploration Using 3D Gravity Inversion In Walker Valley, Nevada Jump to: navigation, search OpenEI Reference...

    4. Advanced Technology Vehicle Lab Benchmarking - Level 2 (in-depth...

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

      More Documents & Publications Advanced Technology Vehicle Lab Benchmarking - Level 2 (in-depth) Data Collection for Improved Cold Temperature Thermal Modeling Advanced Technology ...

    5. A Comparison of Cirrus Cloud Visible Optical Depth Derived from...

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

      Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar Lo, Chaomei Pacific Northwest National Laboratory Comstock, Jennifer Pacific Northwest National Laboratory...

    6. Transit Users Group Supports Transit Agencies with Natural Gas Buses

      SciTech Connect (OSTI)

      Not Available

      2002-04-01

      Fact sheet describes the benefits of the Transit Users Group, which supports transit groups with compressed natural gas (CNG) buses.

    7. Late-time cosmological phase transitions

      SciTech Connect (OSTI)

      Schramm, D.N. Fermi National Accelerator Lab., Batavia, IL )

      1990-11-01

      It is shown that the potential galaxy formation and large-scale structure problems of objects existing at high redshifts (Z {approx gt} 5), structures existing on scales of 100M pc as well as velocity flows on such scales, and minimal microwave anisotropies ({Delta}T/T) {approx lt} 10{sup {minus}5} can be solved if the seeds needed to generate structure form in a vacuum phase transition after decoupling. It is argued that the basic physics of such a phase transition is no more exotic than that utilized in the more traditional GUT scale phase transitions, and that, just as in the GUT case, significant random gaussian fluctuations and/or topological defects can form. Scale lengths of {approximately}100M pc for large-scale structure as well as {approximately}1 M pc for galaxy formation occur naturally. Possible support for new physics that might be associated with such a late-time transition comes from the preliminary results of the SAGE solar neutrino experiment, implying neutrino flavor mixing with values similar to those required for a late-time transition. It is also noted that a see-saw model for the neutrino masses might also imply a tau neutrino mass that is an ideal hot dark matter candidate. However, in general either hot or cold dark matter can be consistent with a late-time transition. 47 refs., 2 figs.

    8. Transit light curves with finite integration time: Fisher information analysis

      SciTech Connect (OSTI)

      Price, Ellen M.; Rogers, Leslie A.

      2014-10-10

      Kepler has revolutionized the study of transiting planets with its unprecedented photometric precision on more than 150,000 target stars. Most of the transiting planet candidates detected by Kepler have been observed as long-cadence targets with 30 minute integration times, and the upcoming Transiting Exoplanet Survey Satellite will record full frame images with a similar integration time. Integrations of 30 minutes affect the transit shape, particularly for small planets and in cases of low signal to noise. Using the Fisher information matrix technique, we derive analytic approximations for the variances and covariances on the transit parameters obtained from fitting light curve photometry collected with a finite integration time. We find that binning the light curve can significantly increase the uncertainties and covariances on the inferred parameters when comparing scenarios with constant total signal to noise (constant total integration time in the absence of read noise). Uncertainties on the transit ingress/egress time increase by a factor of 34 for Earth-size planets and 3.4 for Jupiter-size planets around Sun-like stars for integration times of 30 minutes compared to instantaneously sampled light curves. Similarly, uncertainties on the mid-transit time for Earth and Jupiter-size planets increase by factors of 3.9 and 1.4. Uncertainties on the transit depth are largely unaffected by finite integration times. While correlations among the transit depth, ingress duration, and transit duration all increase in magnitude with longer integration times, the mid-transit time remains uncorrelated with the other parameters. We provide code in Python and Mathematica for predicting the variances and covariances at www.its.caltech.edu/∼eprice.

    9. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation

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

      Report and Appendices | Department of Energy 1.pdf (875.56 KB) More Documents & Publications SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report and Appendices Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices

    10. Detecting Fractures Using Technology at High Temperatures and Depths -

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

      Geothermal Ultrasonic Fracture Imager (GUFI); 2010 Geothermal Technology Program Peer Review Report | Department of Energy Detecting Fractures Using Technology at High Temperatures and Depths - Geothermal Ultrasonic Fracture Imager (GUFI); 2010 Geothermal Technology Program Peer Review Report Detecting Fractures Using Technology at High Temperatures and Depths - Geothermal Ultrasonic Fracture Imager (GUFI); 2010 Geothermal Technology Program Peer Review Report DOE 2010 Geothermal

    11. Electrode immersion depth determination and control in electroslag remelting furnace

      DOE Patents [OSTI]

      Melgaard, David K.; Beaman, Joseph J.; Shelmidine, Gregory J.

      2007-02-20

      An apparatus and method for controlling an electroslag remelting furnace comprising adjusting electrode drive speed by an amount proportional to a difference between a metric of electrode immersion and a set point, monitoring impedance or voltage, and calculating the metric of electrode immersion depth based upon a predetermined characterization of electrode immersion depth as a function of impedance or voltage.

    12. PLANETARY TRANSITS WITH THE ATACAMA LARGE MILLIMETER/SUBMILLIMETER ARRAY RADIO INTERFEROMETER

      SciTech Connect (OSTI)

      Selhorst, C. L.; Barbosa, C. L.; Vlio, Adriana

      2013-11-10

      Planetary transits are commonly observed at visible wavelengths. Here we investigate the shape of a planetary transit observed at radio wavelengths. Solar maps at 17 GHz are used as a proxy for the stellar eclipse by several sizes of planets from super-Earths to hot Jupiters. The relative depth at mid-transit is the same as observed at visible wavelengths, but the limb brightening of the stellar disk at 17 GHz is clearly seen in the shape of the transit light curve. Moreover, when the planet occults an active region the depth of the transit decreases even further, depending on the brightness of the active region relative to the surrounding disk. For intense active region, with 50 times the brightness temperature of the surrounding disk, the decrease can supercede the unperturbed transit depth depending on the size of the eclipsing planet. For a super-Earth (R{sub p} = 0.02 R{sub s} ) crossing, the decrease in intensity is 0.04%, increasing to 0.86% in the case when a strong active region is present. On the other hand, for a hot Jupiter with R{sub p} = 0.17R{sub s} , the unperturbed transit depth is 3% increasing to 4.7% when covering this strong active region. This kind of behavior can be verified with observation of planetary transits with the Atacama Large Millimeter/submillimeter Array radio interferometer.

    13. Hydrogen Transition Study

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

      Transition Study Paul N. Leiby, David L. Greene, Zhenhong Lin, David Bowman, Sujit Das Oak Ridge National Laboratory July 26, 2010 Presented at "Overview of Light-duty Vehicle Studies" Washington, DC Workshop 2 Overview * Some lessons learned from analyzing fuel transitions - Find barriers to transitions significant, but progress being made - Review work by DOE-sponsored team, highlighting key factors * Note some similar findings by NRC * Find important role for policy - in advancing

    14. Site Transition Guidance

      Office of Environmental Management (EM)

      Site Transition Guidance March 2010 Office of Environmental Management U.S. Department of Energy Washington D. C. 20585 Standard Review Plan (SRP) Technical Framework for EM...

    15. Hydrogen Transition Infrastructure Analysis

      SciTech Connect (OSTI)

      Melendez, M.; Milbrandt, A.

      2005-05-01

      Presentation for the 2005 U.S. Department of Energy Hydrogen Program review analyzes the hydrogen infrastructure needed to accommodate a transitional hydrogen fuel cell vehicle demand.

    16. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation

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

      Report and Appendices | Department of Energy Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. 45670-1.pdf (836.62 KB) More Documents & Publications SunLine Transit Agency Fuel Cell Transit

    17. Spatially resolved penetration depth measurements and vortex manipulation in the ferromagnetic superconductor ErNi2B2C

      SciTech Connect (OSTI)

      Wulferding, Dirk; Yang, Ilkyu; Yang, Jinho; Lee, Minkyung; Choi, Hee Cheul; Bud'ko, Sergey L.; Canfield, Paul C.; Yeom, Han Woong; Kim, Jeehoon

      2015-07-31

      We present a local probe study of the magnetic superconductor ErNi2B2C, using magnetic force microscopy at sub-Kelvin temperatures. ErNi2B2C is an ideal system to explore the effects of concomitant superconductivity and ferromagnetism. At 500 mK, far below the transition to a weakly ferromagnetic state, we directly observe a structured magnetic background on the micrometer scale. We determine spatially resolved absolute values of the magnetic penetration depth ? and study its temperature dependence as the system undergoes magnetic phase transitions from paramagnetic to antiferromagnetic, and to weak ferromagnetic, all within the superconducting regime. We estimate the absolute pinning force of Abrikosov vortices, which shows a position dependence and temperature dependence as well, and discuss the possibility of the purported spontaneous vortex formation.

    18. Spatially resolved penetration depth measurements and vortex manipulation in the ferromagnetic superconductor ErNi2B2C

      SciTech Connect (OSTI)

      Wulferding, Dirk; Yang, Ilkyu; Yang, Jinho; Lee, Minkyung; Choi, Hee Cheul; Bud'ko, Sergey L.; Canfield, Paul C.; Yeom, Han Woong; Kim, Jeehoon

      2015-07-31

      We present a local probe study of the magnetic superconductor ErNi2B2C, using magnetic force microscopy at sub-Kelvin temperatures. ErNi2B2C is an ideal system to explore the effects of concomitant superconductivity and ferromagnetism. At 500 mK, far below the transition to a weakly ferromagnetic state, we directly observe a structured magnetic background on the micrometer scale. We determine spatially resolved absolute values of the magnetic penetration depth λ and study its temperature dependence as the system undergoes magnetic phase transitions from paramagnetic to antiferromagnetic, and to weak ferromagnetic, all within the superconducting regime. We estimate the absolute pinning force of Abrikosov vortices, which shows a position dependence and temperature dependence as well, and discuss the possibility of the purported spontaneous vortex formation.

    19. Confocal volume in laser Raman microscopy depth profiling

      SciTech Connect (OSTI)

      Maruyama, Yutaka; Kanematsu, Wataru

      2011-11-15

      To clarify the degradation of confocality in laser Raman microscopy depth profiling (optical sectioning) and the influence of pinhole filtering on it, we investigate the confocal volume in detail based on Gaussian beam optics and scalar wave optics. Theoretical depth profiles of a homogeneous transparent sample for four different pinhole sizes, which are computed using the measured incident beam waist radius w{sub 0} and only a few optical system specific parameters such as a numerical aperture (NA) and a focal length, show a good agreement with the corresponding measured depth profiles. The computed confocal volume demonstrates that the pinhole size affects the actual probe depth as well as the axial resolution and the total intensity loss.

    20. Aerosol Optical Depth Value-Added Product Report

      SciTech Connect (OSTI)

      Koontz, A; Hodges, G; Barnard, J; Flynn, C; Michalsky, J

      2013-03-17

      This document describes the process applied to retrieve aerosol optical depth (AOD) from multifilter rotating shadowband radiometers (MFRSR) and normal incidence multifilter radiometers (NIMFR) operated at the ARM Climate Research Facility’s ground-based facilities.

    1. Heat Flow At Standard Depth | Open Energy Information

      Open Energy Info (EERE)

      to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Heat Flow At Standard Depth Abstract Secular and long-term periodic changes in surface...

    2. Next Generation Nuclear Plant Defense-in-Depth Approach

      SciTech Connect (OSTI)

      Edward G. Wallace; Karl N. Fleming; Edward M. Burns

      2009-12-01

      The purpose of this paper is to (1) document the definition of defense-in-depth and the pproach that will be used to assure that its principles are satisfied for the NGNP project and (2) identify the specific questions proposed for preapplication discussions with the NRC. Defense-in-depth is a safety philosophy in which multiple lines of defense and conservative design and evaluation methods are applied to assure the safety of the public. The philosophy is also intended to deliver a design that is tolerant to uncertainties in knowledge of plant behavior, component reliability or operator performance that might compromise safety. This paper includes a review of the regulatory foundation for defense-in-depth, a definition of defense-in-depth that is appropriate for advanced reactor designs based on High Temperature Gas-cooled Reactor (HTGR) technology, and an explanation of how this safety philosophy is achieved in the NGNP.

    3. Method and apparatus to measure the depth of skin burns

      DOE Patents [OSTI]

      Dickey, Fred M.; Holswade, Scott C.

      2002-01-01

      A new device for measuring the depth of surface tissue burns based on the rate at which the skin temperature responds to a sudden differential temperature stimulus. This technique can be performed without physical contact with the burned tissue. In one implementation, time-dependent surface temperature data is taken from subsequent frames of a video signal from an infrared-sensitive video camera. When a thermal transient is created, e.g., by turning off a heat lamp directed at the skin surface, the following time-dependent surface temperature data can be used to determine the skin burn depth. Imaging and non-imaging versions of this device can be implemented, thereby enabling laboratory-quality skin burn depth imagers for hospitals as well as hand-held skin burn depth sensors the size of a small pocket flashlight for field use and triage.

    4. Assessing the Radiative Impact of Clouds of Low Optical Depth

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

      the Radiative Impact of Clouds of Low Optical Depth W. O'Hirok and P. Ricchiazzi Institute for Computational Earth System Science University of California Santa Barbara, California C. Gautier Department of Geography and Institute for Computational Earth System Science University of California Santa Barbara, California Introduction Analysis from the International Satellite Cloud Climatology Project (ISCCP) reveals that the global mean cloud optical depth is surprisingly low (i.e., τ = 3.8).

    5. Low floor mass transit vehicle

      DOE Patents [OSTI]

      Emmons, J. Bruce; Blessing, Leonard J.

      2004-02-03

      A mass transit vehicle includes a frame structure that provides an efficient and economical approach to providing a low floor bus. The inventive frame includes a stiff roof panel and a stiff floor panel. A plurality of generally vertical pillars extend between the roof and floor panels. A unique bracket arrangement is disclosed for connecting the pillars to the panels. Side panels are secured to the pillars and carry the shear stresses on the frame. A unique seating assembly that can be advantageously incorporated into the vehicle taking advantage of the load distributing features of the inventive frame is also disclosed.

    6. Six novel transition-metal phosphite compounds, with structure related to yavapaiite: Crystal structures and magnetic and thermal properties of A{sup I}[M{sup III}(HPO{sub 3}){sub 2}] (A=K, NH{sub 4}, Rb and M=V, Fe)

      SciTech Connect (OSTI)

      Hamchaoui, Farida; Alonzo, Veronique; Universite Europeenne de Bretagne ; Venegas-Yazigi, Diego; Rebbah, Houria; Le Fur, Eric

      2013-02-15

      Six new transition metal(III) phosphites A{sup I}[V{sup III}(HPO{sub 3}){sub 2}], where A=K (1), NH{sub 4} (2) and Rb (3) and A{sup I}[Fe{sup III}(HPO{sub 3}){sub 2}] where A=K (4), NH{sub 4} (5) and Rb (6) have been synthesized under hydrothermal conditions and the solid-state structures were solved from single-crystal X-ray diffraction data. These compounds crystallize in the hexagonal system, space group P6{sub 3}mc (no. 186), with a=5.3294(2) A and c=12.3130(5) A for 1, a=5.3330(2) A and c=12.8760(4) A for 2, a=5.3459(2) A and c=12.6850(8) A for 3, a=5.3256(1) A and c=12.2362(3) A for 4, a=5.3229(2) A and c=12.8562(4) A for 5, a=5.3393(2) A and c=12.6913(5) A for 6, with Z=2 in the six phases. The crystal structures of these compounds are isotypic and exhibit a layered structure stacked along the c-axis with the A{sup +} cations located in the interlayer space. The [M{sup III}(HPO{sub 3}){sub 2}]{sup -} sheets are formed by MO{sub 6} octahedra interconnected by HPO{sub 3} tetrahedral phosphite oxoanions through sharing vertices. Thermal analysis shows a large range of stability for compounds containing potassium and rubidium cations with decomposition starting around 550 K for stable compounds and above 840 K for the most stable compounds leading in general to pyrophosphate compounds. Triangular nets of metallic centers are observed within the layers in which antiferromagnetic interactions are evidenced by magnetic susceptibility measurements suggesting magnetic frustration. - Graphical abstract: Six new transition metal(III) phosphites A{sup I}[M{sup III}(HPO{sub 3}){sub 2}], where A=K, NH{sub 4}, Rb and M=V, Fe, have been synthesized. The crystal structures of these compounds are isotypic and exhibit a lamellar structure related to Yavapaiite. The M(HPO{sub 3}){sub 2} layers separated by cationic species present the metallic centers in a triangular arrangement. Bulk antiferromagnetic behavior is observed for all the studied compounds. Highlights: Black

    7. Source Parameters for Moderate Earthquakes in the Zagros Mountains with Implications for the Depth Extent of Seismicity

      SciTech Connect (OSTI)

      Adams, A; Brazier, R; Nyblade, A; Rodgers, A; Al-Amri, A

      2009-02-23

      Six earthquakes within the Zagros Mountains with magnitudes between 4.9 and 5.7 have been studied to determine their source parameters. These events were selected for study because they were reported in open catalogs to have lower crustal or upper mantle source depths and because they occurred within an area of the Zagros Mountains where crustal velocity structure has been constrained by previous studies. Moment tensor inversion of regional broadband waveforms have been combined with forward modeling of depth phases on short period teleseismic waveforms to constrain source depths and moment tensors. Our results show that all six events nucleated within the upper crust (<11 km depth) and have thrust mechanisms. This finding supports other studies that call into question the existence of lower crustal or mantle events beneath the Zagros Mountains.

    8. Federal Transit Administration-National Transit Database (NTD...

      Open Energy Info (EERE)

      Type: Dataset User Interface: Website Website: www.ntdprogram.govntdprogram Cost: Free Language: English Federal Transit Administration-National Transit Database (NTD)...

    9. Alternative fuel transit buses

      SciTech Connect (OSTI)

      Motta, R.; Norton, P.; Kelly, K.

      1996-10-01

      The National Renewable Energy Laboratory (NREL) is a U.S. Department of Energy (DOE) national laboratory; this project was funded by DOE. One of NREL`s missions is to objectively evaluate the performance, emissions, and operating costs of alternative fuel vehicles so fleet managers can make informed decisions when purchasing them. Alternative fuels have made greater inroads into the transit bus market than into any other. Each year, the American Public Transit Association (APTA) surveys its members on their inventory and buying plans. The latest APTA data show that about 4% of the 50,000 transit buses in its survey run on an alternative fuel. Furthermore, 1 in 5 of the new transit buses that members have on order are alternative fuel buses. This program was designed to comprehensively and objectively evaluate the alternative fuels in use in the industry.

    10. Oligocyclopentadienyl transition metal complexes

      SciTech Connect (OSTI)

      de Azevedo, Cristina G.; Vollhardt, K. Peter C.

      2002-01-18

      Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

    11. Making the transition to automation

      SciTech Connect (OSTI)

      Christenson, D.J. )

      1992-10-01

      By 1995, the Bureau of Reclamation's hydropower plant near Hungry Horse, Montana, will be remotely operated from Grand Coulee dam (about 300 miles away) in Washington State. Automation at Hungry Horse will eliminate the need for four full-time power plant operators. Between now and then, a transition plan that offers employees choices for retraining, transferring, or taking early retirement will smooth the transition in reducing from five operators to one. The transition plan also includes the use of temporary employees to offset risks of reducing staff too soon. When completed in 1953, the Hungry Horse structure was the world's fourth largest and fourth highest concrete dam. The arch-gravity structure has a crest length of 2,115 feet; it is 3,565 feet above sea level. The four turbine-generator units in the powerhouse total 284 MW, and supply approximately 1 billion kilowatt-hours of electricity annually to the federal power grid managed by the Bonneville Power Administration. In 1988, Reclamation began to automate operations at many of its hydro plants, and to establish centralized control points. The control center concept will increase efficiency. It also will coordinate water movements and power supply throughout the West. In the Pacific Northwest, the Grand Coulee and Black Canyon plants are automated control centers. Several Reclamation-owned facilities in the Columbia River Basin, including Hungry Horse, will be connected to these centers via microwave and telephone lines. When automation is complete, constant monitoring by computer will replace hourly manual readings and equipment checks. Computers also are expected to increase water use efficiency by 1 to 2 percent by ensuring operation for maximum turbine efficiency. Unit efficiency curves for various heads will be programmed into the system.

    12. Measuring depth profiles of residual stress with Raman spectroscopy

      SciTech Connect (OSTI)

      Enloe, W.S.; Sparks, R.G.; Paesler, M.A.

      1988-12-01

      Knowledge of the variation of residual stress is a very important factor in understanding the properties of machined surfaces. The nature of the residual stress can determine a part`s susceptibility to wear deformation, and cracking. Raman spectroscopy is known to be a very useful technique for measuring residual stress in many materials. These measurements are routinely made with a lateral resolution of 1{mu}m and an accuracy of 0.1 kbar. The variation of stress with depth; however, has not received much attention in the past. A novel technique has been developed that allows quantitative measurement of the variation of the residual stress with depth with an accuracy of 10nm in the z direction. Qualitative techniques for determining whether the stress is varying with depth are presented. It is also demonstrated that when the stress is changing over the volume sampled, errors can be introduced if the variation of the stress with depth is ignored. Computer aided data analysis is used to determine the depth dependence of the residual stress.

    13. Buckling transition in long ?-helices

      SciTech Connect (OSTI)

      Palen?r, Peter; Bleha, Tom

      2014-11-07

      The treatment of bending and buckling of stiff biopolymer filaments by the popular worm-like chain model does not provide adequate understanding of these processes at the microscopic level. Thus, we have used the atomistic molecular-dynamic simulations and the Amber03 force field to examine the compression buckling of ?-helix (AH) filaments at room temperature. It was found that the buckling instability occurs in AHs at the critical force f{sub c} in the range of tens of pN depending on the AH length. The decrease of the force f{sub c} with the contour length follows the prediction of the classic thin rod theory. At the force f{sub c} the helical filament undergoes the swift and irreversible transition from the smoothly bent structure to the buckled one. A sharp kink in the AH contour arises at the transition, accompanied by the disruption of the hydrogen bonds in its vicinity. The kink defect brings in an effective softening of the AH molecule at buckling. Nonbonded interactions between helical branches drive the rearrangement of a kinked AH into the ultimate buckled structure of a compact helical hairpin described earlier in the literature.

    14. Site Transition Plan Guidance | Department of Energy

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

      Plan Guidance Site Transition Plan Guidance Site Transition Plan Guidance PDF icon Site Transition Plan Guidance More Documents & Publications Development of Site Transition Plan, ...

    15. Quantum phase transition of condensed bosons in optical lattices

      SciTech Connect (OSTI)

      Liang Junjun; Liang, J.-Q.; Liu, W.-M.

      2003-10-01

      In this paper we study the superfluid-Mott-insulator phase transition of ultracold dilute gas of bosonic atoms in an optical lattice by means of Green function method and Bogliubov transformation as well. The superfluid-Mott-insulator phase transition condition is determined by the energy-band structure with an obvious interpretation of the transition mechanism. Moreover the superfluid phase is explained explicitly from the energy spectrum derived in terms of Bogliubov approach.

    16. Microsoft Word - SEC J_Appendix C - Contractor's Transition Plan_Negotiated

      National Nuclear Security Administration (NNSA)

      C, Page 1 SECTION J APPENDIX C CONTRACTOR'S TRANSITION PLAN Plan: As attached below. Guidance: The Contractor shall submit a Transition Plan that describes the process, details, and schedule for providing an orderly transition during the Contract's Transition Term stated in Section F, F-2, Period of Performance, in accordance with the guidance herein for all elements of Section J, Appendix A, Statement of Work, Chapter II Work Scope Structure. The objectives of the Transition Plan are: to

    17. Gulf of Mexico Proved Reserves By Water Depth, 2009

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

      Gulf of Mexico Proved Reserves and Production by Water Depth, 2009 1 Gulf of Mexico Proved Reserves and Production by Water Depth The Gulf of Mexico Federal Offshore region (GOM Fed) has long been one of the Nation's principal sources of proved reserves. At the end of 2009, the GOM Fed accounted for close to one-fifth of oil proved reserves (second only to Texas) and just over four percent of natural gas proved reserves (the country's seventh largest reporting region). 1 Natural gas proved

    18. Examining hydrogen transitions.

      SciTech Connect (OSTI)

      Plotkin, S. E.; Energy Systems

      2007-03-01

      This report describes the results of an effort to identify key analytic issues associated with modeling a transition to hydrogen as a fuel for light duty vehicles, and using insights gained from this effort to suggest ways to improve ongoing modeling efforts. The study reported on here examined multiple hydrogen scenarios reported in the literature, identified modeling issues associated with those scenario analyses, and examined three DOE-sponsored hydrogen transition models in the context of those modeling issues. The three hydrogen transition models are HyTrans (contractor: Oak Ridge National Laboratory), MARKAL/DOE* (Brookhaven National Laboratory), and NEMS-H2 (OnLocation, Inc). The goals of these models are (1) to help DOE improve its R&D effort by identifying key technology and other roadblocks to a transition and testing its technical program goals to determine whether they are likely to lead to the market success of hydrogen technologies, (2) to evaluate alternative policies to promote a transition, and (3) to estimate the costs and benefits of alternative pathways to hydrogen development.

    19. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation

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

      Report and Appendices | Department of Energy Second Evaluation Report and Appendices Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. 45670-2.pdf (1.25 MB) More Documents & Publications Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third

    20. Continuous Snow Depth, Intensive Site 1, Barrow, Alaska

      DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

      Bob Busey; Larry Hinzman; Vladimir Romanovsky; William Cable

      2014-11-06

      Continuous Snow depth data are being collected at several points within four intensive study areas in Barrow, Alaska. These data are being collected to better understand the energy dynamics above the active layer and permafrost. They complement in-situ snow and soil measurements at this location. The data could also be used as supporting measurements for other research and modeling activities.

    1. Continuous Snow Depth, Intensive Site 1, Barrow, Alaska

      DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

      Bob Busey; Larry Hinzman; Vladimir Romanovsky; William Cable

      Continuous Snow depth data are being collected at several points within four intensive study areas in Barrow, Alaska. These data are being collected to better understand the energy dynamics above the active layer and permafrost. They complement in-situ snow and soil measurements at this location. The data could also be used as supporting measurements for other research and modeling activities.

    2. Transition Plan | Department of Energy

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

      Transition Plan Transition Plan This template is used to define the objectives, resources, and plans for systems transition, e.g., scheduling the transition from acceptance testing to full operational status, identifying staffing and training needs for system operation and maintenance, planning for data migration, etc Transition Plan (35.86 KB) More Documents & Publications System Design Feasibility Study Report Template Configuration Management Plan

    3. Magnetic blackbody shift of hyperfine transitions for atomic clocks

      SciTech Connect (OSTI)

      Berengut, J. C.; Flambaum, V. V.; King-Lacroix, J.

      2009-12-15

      We derive an expression for the magnetic blackbody shift of hyperfine transitions such as the cesium primary reference transition which defines the second. The shift is found to be a complicated function of temperature, and has a T{sup 2} dependence only in the high-temperature limit. We also calculate the shift of ground-state p{sub 1/2} hyperfine transitions which have been proposed as new atomic clock transitions. In this case interaction with the p{sub 3/2} fine-structure multiplet may be the dominant effect.

    4. Variational transition state theory

      SciTech Connect (OSTI)

      Truhlar, D.G.

      1993-12-01

      This research program involves the development of variational transition state theory (VTST) and semiclassical tunneling methods for the calculation of gas-phase reaction rates and selected applications. The applications are selected for their fundamental interest and/or their relevance to combustion.

    5. Transition Implementation Guide

      Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

      2001-04-24

      This Guide was prepared to aid in the development, planning, and implementation of requirements and activities during the transition phase at Department of Energy (DOE) facilities that have been declared or are forecast to become excess to any future mission requirements.

    6. A microwave resonator for limiting depth sensitivity for electron paramagnetic resonance spectroscopy of surfaces

      SciTech Connect (OSTI)

      Sidabras, Jason W.; Varanasi, Shiv K.; Hyde, James S.; Mett, Richard R.; Swarts, Steven G.; Swartz, Harold M.

      2014-10-15

      A microwave Surface Resonator Array (SRA) structure is described for use in Electron Paramagnetic Resonance (EPR) spectroscopy. The SRA has a series of anti-parallel transmission line modes that provides a region of sensitivity equal to the cross-sectional area times its depth sensitivity, which is approximately half the distance between the transmission line centers. It is shown that the quarter-wave twin-lead transmission line can be a useful element for design of microwave resonators at frequencies as high as 10 GHz. The SRA geometry is presented as a novel resonator for use in surface spectroscopy where the region of interest is either surrounded by lossy material, or the spectroscopist wishes to minimize signal from surrounding materials. One such application is in vivo spectroscopy of human finger-nails at X-band (9.5 GHz) to measure ionizing radiation dosages. In order to reduce losses associated with tissues beneath the nail that yield no EPR signal, the SRA structure is designed to limit depth sensitivity to the thickness of the fingernail. Another application, due to the resonator geometry and limited depth penetration, is surface spectroscopy in coating or material science. To test this application, a spectrum of 1.44 μM of Mg{sup 2+} doped polystyrene 1.1 mm thick on an aluminum surface is obtained. Modeling, design, and simulations were performed using Wolfram Mathematica (Champaign, IL; v. 9.0) and Ansys High Frequency Structure Simulator (HFSS; Canonsburg, PA; v. 15.0). A micro-strip coupling circuit is designed to suppress unwanted modes and provide a balanced impedance transformation to a 50 Ω coaxial input. Agreement between simulated and experimental results is shown.

    7. A new look at Spitzer primary transit observations of the exoplanet HD 189733b

      SciTech Connect (OSTI)

      Morello, G.; Waldmann, I. P.; Tinetti, G.; Howarth, I. D.; Peres, G.; Micela, G.

      2014-05-01

      Blind source separation techniques are used to reanalyze two exoplanetary transit light curves of the exoplanet HD 189733b recorded with the IR camera IRAC on board the Spitzer Space Telescope at 3.6 μm during the 'cold' era. These observations, together with observations at other IR wavelengths, are crucial to characterize the atmosphere of the planet HD 189733b. Previous analyses of the same data sets reported discrepant results, hence the necessity of the reanalyses. The method we used here is based on the Independent Component Analysis (ICA) statistical technique, which ensures a high degree of objectivity. The use of ICA to detrend single photometric observations in a self-consistent way is novel in the literature. The advantage of our reanalyses over previous work is that we do not have to make any assumptions on the structure of the unknown instrumental systematics. Such 'admission of ignorance' may result in larger error bars than reported in the literature, up to a factor 1.6. This is a worthwhile tradeoff for much higher objectivity, necessary for trustworthy claims. Our main results are (1) improved and robust values of orbital and stellar parameters, (2) new measurements of the transit depths at 3.6 μm, (3) consistency between the parameters estimated from the two observations, (4) repeatability of the measurement within the photometric level of ∼2 × 10{sup –4} in the IR, and (5) no evidence of stellar variability at the same photometric level within one year.

    8. Pressure induced phase transitions in ceramic compounds containing tetragonal zirconia

      SciTech Connect (OSTI)

      Sparks, R.G.; Pfeiffer, G.; Paesler, M.A.

      1988-12-01

      Stabilized tetragonal zirconia compounds exhibit a transformation toughening process in which stress applied to the material induces a crystallographic phase transition. The phase transition is accompanied by a volume expansion in the stressed region thereby dissipating stress and increasing the fracture strength of the material. The hydrostatic component of the stress required to induce the phase transition can be investigated by the use of a high pressure technique in combination with Micro-Raman spectroscopy. The intensity of Raman lines characteristic for the crystallographic phases can be used to calculate the amount of material that has undergone the transition as a function of pressure. It was found that pressures on the order of 2-5 kBar were sufficient to produce an almost complete transition from the original tetragonal to the less dense monoclinic phase; while a further increase in pressure caused a gradual reversal of the transition back to the original tetragonal structure.

    9. Synthesis of transition metal carbonitrides

      DOE Patents [OSTI]

      Munir, Zuhair A. R.; Eslamloo-Grami, Maryam

      1994-01-01

      Transition metal carbonitrides (in particular, titanium carbonitride, TiC.sub.0.5 N.sub.0.5) are synthesized by a self-propagating reaction between the metal (e.g., titanium) and carbon in a nitrogen atmosphere. Complete conversion to the carbonitride phase is achieved with the addition of TiN as diluent and with a nitrogen pressure .gtoreq.0.6 MPa. Thermodynamic phase-stability calculations and experimental characterizations of quenched samples provided revealed that the mechanism of formation of the carbonitride is a two-step process. The first step involves the formation of the nonstoichiometric carbide, TiC.sub.0.5, and is followed by the formation of the product by the incorporation of nitrogen in the defect-structure carbide.

    10. RFID tag modification for full depth backscatter modulation

      DOE Patents [OSTI]

      Scott, Jeffrey Wayne [Pasco, WA; Pratt, Richard M [Richland, WA

      2010-07-20

      A modulated backscatter radio frequency identification device includes a diode detector configured to selectively modulate a reply signal onto an incoming continuous wave; communications circuitry configured to provide a modulation control signal to the diode detector, the diode detector being configured to modulate the reply signal in response to be modulation control signal; and circuitry configured to increase impedance change at the diode detector which would otherwise not occur because the diode detector rectifies the incoming continuous wave while modulating the reply signal, whereby reducing the rectified signal increases modulation depth by removing the reverse bias effects on impedance changes. Methods of improving depth of modulation in a modulated backscatter radio frequency identification device are also provided.

    11. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary

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

      Evaluation Results | Department of Energy Preliminary Evaluation Results Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results This report provides preliminary results from the evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment, early results and agency experience are also provided. 43847.pdf (1.59 MB) More Documents & Publications

    12. Laser induced popcornlike conformational transition of nanodiamond as a nanoknife

      SciTech Connect (OSTI)

      Chang, C.-C.; Chen, P.-H.; Chu, H.-L.; Lee, T.-C.; Chou, C.-C.; Chao, J.-I; Su, C.-Y.; Chen, J.S.; Tsai, J.-S.; Tsai, C.-M.; Ho, Y.-P.; Sun, K.W.; Cheng, C.-L.; Chen, F.-R.

      2008-07-21

      Nanodiamond (ND) is surrounded by layers of graphite on its surface. This unique structure feature creates unusual fluorescence spectra, which can be used as an indicator to monitor its surface modification. Meanwhile, the impurity, nitroso (C-N=O) inside the ND can be photolyzed by two-photon absorption, releasing NO to facilitate the formation of a sp{sup 3} diamond structure in the core of ND and transforming it into a sp{sup 2} graphite structure. Such a conformational transition enlarges the size of ND from 8 to 90 nm, resulting in a popcornlike structure. This transition reaction may be useful as nanoknives in biomedical application.

    13. Phase transitions and compressibility of NaMgF[subscript 3] ...

      Office of Scientific and Technical Information (OSTI)

      Title: Phase transitions and compressibility of NaMgFsubscript 3 (Neighborite) in perovskite- and post perovskite-related structures Authors: Martin, C. David ; Crichton, Wilson ...

    14. transitional | netl.doe.gov

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

      from Flue Gas by Phase Transitional Absorption Project No.: FG26-05NT42488 Basic Illustration of the Phase Transitional Absorption Process. Basic Illustration of the Phase Transitional Absorption Process. Hampton University researched a novel carbon dioxide (CO2) absorption concept, phase transitional absorption, that utilizes a two-part proprietary absorbent consisting of an activated agent dissolved in a solvent. Phase separation of the activated agent from the chemical solvent occurs during

    15. Elasticity and Inverse Temperature Transition in Elastin

      SciTech Connect (OSTI)

      Perticaroli, Stefania; Ehlers, Georg; Jalarvo, Niina; Katsaras, John; Nickels, Jonathan D.

      2015-09-22

      Structurally, elastin is protein and biomaterial that provides elasticity and resilience to a range of tissues. This work provides insights into the elastic properties of elastin and its peculiar inverse temperature transition (ITT). These features are dependent on hydration of elastin and are driven by a similar mechanism of hydrophobic collapse to an entropically favorable state. Moreover, when using neutron scattering, we quantify the changes in the geometry of molecular motions above and below the transition temperature, showing a reduction in the displacement of water-induced motions upon hydrophobic collapse at the ITT. Finally, we measured the collective vibrations of elastin gels as a function of elongation, revealing no changes in the spectral features associated with local rigidity and secondary structure, in agreement with the entropic origin of elasticity.

    16. Elasticity and Inverse Temperature Transition in Elastin

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

      Perticaroli, Stefania; Ehlers, Georg; Jalarvo, Niina; Katsaras, John; Nickels, Jonathan D.

      2015-09-22

      Structurally, elastin is protein and biomaterial that provides elasticity and resilience to a range of tissues. This work provides insights into the elastic properties of elastin and its peculiar inverse temperature transition (ITT). These features are dependent on hydration of elastin and are driven by a similar mechanism of hydrophobic collapse to an entropically favorable state. Moreover, when using neutron scattering, we quantify the changes in the geometry of molecular motions above and below the transition temperature, showing a reduction in the displacement of water-induced motions upon hydrophobic collapse at the ITT. Finally, we measured the collective vibrations of elastinmore » gels as a function of elongation, revealing no changes in the spectral features associated with local rigidity and secondary structure, in agreement with the entropic origin of elasticity.« less

    17. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

      Broader source: Energy.gov [DOE]

      This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

    18. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

      SciTech Connect (OSTI)

      Chandler, K.; Eudy, L.

      2007-03-01

      This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

    19. Site Transition Process Upon Cleanup Completion | Department...

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

      Process Upon Cleanup Completion Site Transition Process Upon Cleanup Completion Site Transition Process Upon Cleanup Completion PDF icon Site Transition Process Upon Cleanup ...

    20. Transition of Sites from Environmental Management Memorandum...

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

      Transition of Sites from Environmental Management Memorandum of Understanding Transition of Sites from Environmental Management Memorandum of Understanding Transition of Sites from ...

    1. Site Transition Framework | Department of Energy

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

      Site Transition Framework (April 2004) PDF icon Site Transition Framework More Documents & Publications Process for Transition of Uranium Mill Tailings Radiation Control Act Title ...

    2. Alternative Fuel Transit Buses

      Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

      35th St. Craig Ave. Alt Blvd. Colucci Pkwy. Final Results from the National Renewable Energy Laboratory Vehicle Evaluation Program Final Results from the National Renewable Energy Laboratory Vehicle Evaluation Program N T Y A U E O F E N E R G D E P A R T M E N I T E D S T A T S O F A E R I C M Produced for the U.S. Department of Energy (DOE) by the National Renewable Energy Laboratory (NREL), a U.S. DOE national laboratory Transit Buses Alternative Fuel Alternative Fuel Final Results from the

    3. Transition Metal Switchable Mirror

      ScienceCinema (OSTI)

      None

      2013-05-29

      The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

    4. Transition Metal Switchable Mirror

      ScienceCinema (OSTI)

      None

      2010-01-08

      The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

    5. Dynamics of the magneto structural phase transition in La(Fe{sub 0.9}Co{sub 0.015}Si{sub 0.085}){sub 13} observed by magneto-optical imaging

      SciTech Connect (OSTI)

      Kuepferling, M. Basso, V.; Bennati, C.; Laviano, F.; Ghigo, G.

      2014-05-07

      We investigate the temperature induced ferromagnetic to paramagnetic phase transition in Co substituted La(Fe{sub x}Co{sub y}Si{sub 1−x−y}){sub 13} with x = 0.9 and low Co content of y = 0.015 (T{sub c}≃200 K) by means of magneto-optical imaging with indicator film and by calorimetry at very low temperature rates. We were able to visualize the motion of the ferromagnetic (FM)/paramagnetic (PM) front which is forming reproducible patterns independently of the temperature rate. The average velocity of the FM/PM front was calculated to be 10{sup −4} m/s during the continuous propagation and 4×10{sup −3} m/s during an avalanche. The heat flux was measured at low temperature rates by a differential scanning calorimeter and shows a reproducible sequence of individual and separated avalanches which occurs independently of the rate. We interpret the observed effects as the result of the athermal character of the phase transition.

    6. Report on the Depth Requirements for a Massive Detector at Homestake

      SciTech Connect (OSTI)

      Bernstein,A.; Blucher, E.; Cline, D. B.; Diwan, M. V.; Fleming, b.; Kadel, R.; Kearns, E.; Klein, J.; Lande, K.; Lanni, F.; Lissauer, D.; McKeown, R.; Morse, W.; Radeika, R.; Scholberg, K.; Smy, M.; Sobel, H.; Sullivan, G.; Svoboda, R.; Vagins, M.; Walter, C.; Zwaska, R.

      2008-12-22

      depth should be sufficient for any possible future use of these cavities or the level which will be developed for these large structures. Along with these physics justifications there are practical issues regarding the existing infrastructure at Homestake and also the stress characteristics of the Homestake rock formations. In this report we will examine the various depth choices at Homestake from the point of view of the particle and nuclear physics signatures of interest. We also have sufficient information about the existing infrastructure and the rock characteristics to narrow the choice of levels for the development of large cavities with long lifetimes. We make general remarks on desirable ground conditions for such large cavities and then make recommendations on how to start examining these levels to make a final choice. In the appendix we have outlined the initial requirements for the detectors. These requirements will undergo refinement during the course of the design. Finally, we strongly recommend that the geotechnical studies be commenced at the 4850 ft level, which we find to be the most suitable, in a timely manner.

    7. Report on the Depth Requirements for a Massive Detector at Homestake

      SciTech Connect (OSTI)

      Kadel, Richard W.; Bernstein, Adam; Blucher, Edward; Cline, David B.; Diwan, Milind V.; Fleming, Bonnie; Kearns, Edward; Klein, Joshua; Lande, Kenneth; Lanni, Francesco; Lissauer, David; McKeown, Robert; Morse, William; Rameika, Regina; Scholberg, Kate; Smy, Michael; Sobel, Henry; Sullivan, Gregory; Svoboda, Robert; Vagins, Mark; Walter, Christopher; Zwaska, Robert

      2008-12-23

      currently planned detectors or new technologies. Therefore the depth requirement also needs to be made on the basis of sound judgment regarding possible future use. In particular, the depth should be sufficient for any possible future use of these cavities or the level which will be developed for these large structures.Along with these physics justifications there are practical issues regarding the existing infrastructure at Homestake and also the stress characteristics of the Homestake rock formations. In this report we will examine the various depth choices at Homestake from the point of view of the particle and nuclear physics signatures of interest. We also have sufficient information about the existing infrastructure and the rock characteristics to narrow the choice of levels for the development of large cavities with long lifetimes. We make general remarks on desirable ground conditions for such large cavities and then make recommendations on how to start examining these levels to make a final choice. In the appendix we have outlined the initial requirements for the detectors. These requirements will undergo refinement during the course of the design. Finally, we strongly recommend that the geotechnical studies be commenced at the 4850 ft level, which we find to be the most suitable, in a timely manner.

    8. Phase diagram and incommensurate antiferroelectric structure in (Pb{sub 1?1.5x}La{sub x})(Zr{sub 0.42}Sn{sub 0.40}Ti{sub 0.18})O{sub 3} ceramics discovered by band-to-band optical transitions

      SciTech Connect (OSTI)

      Ding, X. J.; Xu, L. P.; Hu, Z. G. Chu, J. H.; Chen, X. F.; Wang, G. S.; Dong, X. L.

      2014-09-29

      Optical properties and phase transitions of (Pb{sub 1?1.5x}La{sub x})(Zr{sub 0.42}Sn{sub 0.40}Ti{sub 0.18})O{sub 3} (PLZST 100x/42/40/18) ceramics with different compositions have been investigated by temperature dependent spectroscopic ellipsometry. Two interband critical points (E{sub cp1} and E{sub cp2}) located at about 3.9 and 5.1?eV can be obtained by fitting standard line shapes to the second derivatives of the complex dielectric functions. Based on the band-to-band transitions, the phase diagram of PLZST ceramics can be well presented. Moreover, a peculiar incommensurate antiferroelectric state has been found to exist above the temperature of the normal commensurate antiferroelectric tetragonal structure. It can be stable below Curie temperature, evolving slowly with decreasing temperature towards the commensurate structure, which is due to strong pinning of incommensurate domain walls. The phenomena can result from a competition between ferroelectric ordering and antiferroelectric ordering caused by the lanthanum modification.

    9. Structural/magnetic phase transitions and superconductivity in Ba(Fe1-xTMx)2As2 (TM=Co, Ni, Cu, Co/Cu, Rh and Pd) single crystals

      SciTech Connect (OSTI)

      Ni, Ni

      2009-08-15

      Since its discovery in 1911, superconductivity has been one of the most actively studied fields in condensed matter physics and has attracted immense experimental and theoretical effort. At this point in time, with more and more superconductors discovered in elements, alloys, intermetallic compounds and oxides, it is becoming clear that superconductivity is actually not so rare in nature. Almost half of the elements in the periodic table and hundreds of compounds have been found to be superconducting. Fig. 1.1 shows the milestones in discovering higher T{sub c} superconductors. Among the elemental superconductors, Niobium has the highest superconducting transition temperature, T{sub c}, of 9.5 K. This record held for more than ten years, until the discovery of niobium nitride which superconducts below 16 K. It took another thirty years for T{sub c} to increase from 16 K in niobium nitride to 23 K in niobium germanium.

    10. Low temperature London penetration depth and superfluid density in Fe-based superconductors

      SciTech Connect (OSTI)

      Kim, Hyunsoo

      2013-05-15

      The superconducting gap symmetry of the Fe-based superconductors was studied by measurements and analysis of London penetration depth and super uid density. Tunnel diode resonator technique for these measurements was implemented in a dilution refrigerator allowing for the temperatures down to 50 mK. For the analysis of the super uid density, we used both experimental studies of Al-coated samples and original thermodynamic approach based on Rutgers relation. In three systems studied, we found that the superconducting gap at the optimal doping is best described in multi-gap full gap scenario. By performing experiments on samples with arti#12;cially introduced disorder with heavy ion irradiation, we show that evolution of the superconducting transition temperature and of the super uid density are consistent with full-gap sign changing s#6; superconducting state. The superconducting gap develops strong modulation both in the under-doped and the over-doped regimes. In the terminal hole-doped KFe{sub 2}As{sub 2}, both temperature dependence of the super uid density and its evolution with increase of the scattering rate are consistent with symmetry imposed vertical line nodes in the superconducting gap. By comparative studies of hole-doped (Ba,K)Fe{sub 2}As{sub 2} and electron-doped Ca10-3-8, we show that the superconducting gap modulation in the under-doped regime is intrinsic and is not induced by the coexisting static magnetic order.

    11. Laser Acoustic Molten Metal Depth Sensing in Titanium

      SciTech Connect (OSTI)

      J. B. Walter; K. L. Telschow; R. E. Haun

      1999-09-22

      A noncontacting ultrasonic method has been investigated for probing the solidification front in molten titanium for the purposes of profiling the channel depth in a plasma hearth re-melter. The method, known as Laser Ultrasonics, utilized a pulsed laser for generation of ultrasonic waves at the surface of a molten metal pool. The ultrasonic waves propagated into the liquid titanium reflected from the solidification front and the boundaries of the solid plug. A Fabry-Perot interferometer, driven by a second laser, demodulated the small displacements caused by the ultrasonic wave motion at the liquid surface. The method and results of measurements taken within a small research plasma melting furnace will be described. Successful results were obtained even directly beneath the plasma arc using this all-optical approach.

    12. Laser Acoustic Molten Metal Depth Sensing in Titanium

      SciTech Connect (OSTI)

      Walter, John Bradley; Telschow, Kenneth Louis; Haun, R.E.

      1999-08-01

      A noncontacting ultrasonic method has been investigated for probing the solidification front in molten titanium for the purposes of profiling the channel depth in plasma hearth re-melter. The method, known as Laser Ultrasonics, utilized a pulsed laser for generation of ultrasonic waves at the surface of a molten metal pool. The ultrasonic waves propagated into the liquid titanium reflected from the solidification front and the boundaries of the solid plug. A Fabry-Perot interferometer, driven by a second laser, demodulated the small displacements caused by the ultrasonic wave motion at the liquid surface. The method and results of measurements taken within a small research plasma melting furnace will be described. Successful results were obtained even directly beneath the plasma arc using this all optical approach.

    13. The nature of the first order isostructural transition in GdRhSn...

      Office of Scientific and Technical Information (OSTI)

      ZrNiAl type hexagonal crystal structure at room temperature and undergoes a first order iso-structural transition in the paramagnetic state at 245 K. The unit cell volume change at ...

    14. Cluster Monte Carlo simulations of the nematic-isotropic transition

      SciTech Connect (OSTI)

      Priezjev, N. V.; Pelcovits, Robert A.

      2001-06-01

      We report the results of simulations of the three-dimensional Lebwohl-Lasher model of the nematic-isotropic transition using a single cluster Monte Carlo algorithm. The algorithm, first introduced by Kunz and Zumbach to study two-dimensional nematics, is a modification of the Wolff algorithm for spin systems, and greatly reduces critical slowing down. We calculate the free energy in the neighborhood of the transition for systems up to linear size 70. We find a double well structure with a barrier that grows with increasing system size. We thus obtain an upper estimate of the value of the transition temperature in the thermodynamic limit.

    15. Stochastic Seismic Response of an Algiers Site with Random Depth to Bedrock

      SciTech Connect (OSTI)

      Badaoui, M.; Mebarki, A.; Berrah, M. K.

      2010-05-21

      Among the important effects of the Boumerdes earthquake (Algeria, May 21{sup st} 2003) was that, within the same zone, the destructions in certain parts were more important than in others. This phenomenon is due to site effects which alter the characteristics of seismic motions and cause concentration of damage during earthquakes. Local site effects such as thickness and mechanical properties of soil layers have important effects on the surface ground motions.This paper deals with the effect of the randomness aspect of the depth to bedrock (soil layers heights) which is assumed to be a random variable with lognormal distribution. This distribution is suitable for strictly non-negative random variables with large values of the coefficient of variation. In this case, Monte Carlo simulations are combined with the stiffness matrix method, used herein as a deterministic method, for evaluating the effect of the depth to bedrock uncertainty on the seismic response of a multilayered soil. This study considers a P and SV wave propagation pattern using input accelerations collected at Keddara station, located at 20 km from the epicenter, as it is located directly on the bedrock.A parametric study is conducted do derive the stochastic behavior of the peak ground acceleration and its response spectrum, the transfer function and the amplification factors. It is found that the soil height heterogeneity causes a widening of the frequency content and an increase in the fundamental frequency of the soil profile, indicating that the resonance phenomenon concerns a larger number of structures.

    16. An in-depth longitudinal analysis of mixing patterns in a small scientific collaboration network

      SciTech Connect (OSTI)

      Rodriguez, Marko A; Pepe, Alberto

      2009-01-01

      Many investigations of scientific collaboration are based on large-scale statistical analyses of networks constructed from bibliographic repositories. These investigations often rely on a wealth of bibliographic data, but very little or no other information about the individuals in the network, and thus, fail to illustate the broader social and academic landscape in which collaboration takes place. In this article, we perform an in-depth longitudinal analysis of a small-scale network of scientific collaboration (N = 291) constructed from the bibliographic record of a research center involved in the development and application of sensor network technologies. We perform a preliminary analysis of selected structural properties of the network, computing its range, configuration and topology. We then support our preliminary statistical analysis with an in-depth temporal investigation of the assortativity mixing of these node characteristics: academic department, affiliation, position, and country of origin of the individuals in the network. Our qualitative analysis of mixing patterns offers clues as to the nature of the scientific community being modeled in relation to its organizational, disciplinary, institutional, and international arrangements of collaboration.

    17. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

      SciTech Connect (OSTI)

      Chandler, K.; Eudy, L.

      2008-10-01

      This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

    18. Aerosol Optical Depth Value-Added Product for the SAS-He Instrument...

      Office of Scientific and Technical Information (OSTI)

      Aerosol Optical Depth Value-Added Product for the SAS-He Instrument Citation Details In-Document Search Title: Aerosol Optical Depth Value-Added Product for the SAS-He Instrument ...

    19. Taking Oil and Gas Exploration to New Depths | GE Global Research

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

      Taking Oil and Gas Exploration to New Depths Click to email this to a friend (Opens in new ... Taking Oil and Gas Exploration to New Depths Oliver Astley 2014.11.12 The challenges of ...

    20. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Third Evaluation Report

      Broader source: Energy.gov [DOE]

      This report describes operations at Alameda-Contra Costa Transit district for three protoype fuel cell buses and six diesel buses operating from the same location.

    1. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Third Evaluation Report- Appendices

      Broader source: Energy.gov [DOE]

      This report describes operations at Alameda-Contra Costa Transit district for three protoype fuel cell buses and six diesel buses operating from the same location.

    2. Tritium research laboratory cleanup and transition project final report

      SciTech Connect (OSTI)

      Johnson, A.J.

      1997-02-01

      This Tritium Research Laboratory Cleanup and Transition Project Final Report provides a high-level summary of this project`s multidimensional accomplishments. Throughout this report references are provided for in-depth information concerning the various topical areas. Project related records also offer solutions to many of the technical and or administrative challenges that such a cleanup effort requires. These documents and the experience obtained during this effort are valuable resources to the DOE, which has more than 1200 other process contaminated facilities awaiting cleanup and reapplication or demolition.

    3. Energy Transition Initiative: Islands Playbook

      Broader source: Energy.gov [DOE]

      The Island Energy Playbook provides an action-oriented guide to successfully initiating, planning, and completing a transition to an energy system that primarily relies on local resources to eliminate a dependence on one or two imported fuels. It is intended to serve as a readily available framework that any community can adapt to organize its own energy transition effort.

    4. Alternative Fuels Data Center: Mass Transit

      Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

      Mass Transit to someone by E-mail Share Alternative Fuels Data Center: Mass Transit on Facebook Tweet about Alternative Fuels Data Center: Mass Transit on Twitter Bookmark Alternative Fuels Data Center: Mass Transit on Google Bookmark Alternative Fuels Data Center: Mass Transit on Delicious Rank Alternative Fuels Data Center: Mass Transit on Digg Find More places to share Alternative Fuels Data Center: Mass Transit on AddThis.com... More in this section... Idle Reduction Parts & Equipment

    5. Transition metal catalysis in the generation of natural gas

      SciTech Connect (OSTI)

      Mango, F.D.

      1995-12-31

      The view that natural gas is thermolytic, coming from decomposing organic debris, has remained almost unchallenged for nearly half a century. Disturbing contradictions exist, however: Oil is found at great depth, at temperatures where only gas should exist and oil and gas deposits show no evidence of the thermolytic debris indicative of oil decomposing to gas. Moreover, laboratory attempts to duplicate the composition of natural gas, which is typically between 60 and 95+ wt% methane in C{sub 1}-C{sub 4}, have produced insufficient amounts of methane (10 to 60%). It has been suggested that natural gas may be generated catalytically, promoted by the transition metals in carbonaceous sedimentary rocks. This talk will discuss experimental results that support this hypothesis. Various transition metals, as pure compounds and in source rocks, will be shown to generate a catalytic gas that is identical to natural gas. Kinetic results suggest robust catalytic activity under moderate catagenetic conditions.

    6. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation...

      Energy Savers [EERE]

      Fourth Evaluation Report and Appendices SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report and Appendices This report describes operations at SunLine Transit ...

    7. Washington Metropolitan Area Transit Authority: Compressed Natural Gas Transit Bus Evaluation

      SciTech Connect (OSTI)

      Chandler, K.; Eberts, E.; Melendez, M.

      2006-04-01

      Evaluates compressed natural gas (CNG) powered transit buses at Washington Metropolitan Area Transit Authority (WMATA), providing a comparison between them and standard diesel transit buses.

    8. Toward the detection of exoplanet transits with polarimetry

      SciTech Connect (OSTI)

      Wiktorowicz, Sloane J.; Laughlin, Gregory P.

      2014-11-01

      In contrast to photometric transits, whose peak signal occurs at mid-transit due to occultation of the brightest region of the disk, polarimetric transits provide a signal upon ingress and egress due to occultation of the polarized stellar limb. Limb polarization, the bright corollary to limb darkening, arises from the 90 scattering angle and low optical depth experienced by photons at the limb. In addition to the ratio R {sub p}/R {sub *}, the amplitude of a polarimetric transit is expected to be controlled by the strength and width of the stellar limb polarization profile, which depend on the scattering-to-total opacity ratio at the stellar limb. We present a short list of the systems providing the highest expected signal-to-noise ratio for detection of this effect, and we draw particular attention to HD 80606b. This planet is spin/orbit misaligned, has a three-hour ingress, and has a bright parent star, which make it an attractive target. We report on test observations of an HD 80606b ingress with the POLISH2 polarimeter at the Lick Observatory Shane 3 m telescope. We conclude that unmodeled telescope systematic effects prevented polarimetric detection of this event. We outline a roadmap for further refinements of exoplanet polarimetry, whose eventual success will require a further factor of ten reduction in systematic noise.

    9. Boundaries for martensitic transition of 7Li under pressure

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

      Schaeffer, Anne Marie; Cai, Weizhao; Olejnik, Ella; Molaison, Jamie J.; Sinogeikin, Stanislav; dos Santos, Antonio M.; Deemyad, Shanti

      2015-08-14

      We report that physical properties of lithium under extreme pressures continuously reveal unexpected features. These include a sequence of structural transitions to lower symmetry phases, metal-insulator-metal transition, superconductivity with one of the highest elemental transition temperatures, and a maximum followed by a minimum in its melting line. The instability of the bcc structure of lithium is well established by the presence of a temperature-driven martensitic phase transition. The boundaries of this phase, however, have not been previously explored above 3 GPa. All higher pressure phase boundaries are either extrapolations or inferred based on indirect evidence. Here we explore the pressuremore » dependence of the martensitic transition of lithium up to 7 GPa using a combination of neutron and X-ray scattering. We find a rather unexpected deviation from the extrapolated boundaries of the hR3 phase of lithium. Furthermore, there is evidence that, above ~3 GPa, once in fcc phase, lithium does not undergo a martensitic transition.« less

    10. Two glass transitions in miscible polymer blends?

      SciTech Connect (OSTI)

      Dudowicz, Jacek; Freed, Karl F.; Douglas, Jack F.

      2014-06-28

      In contrast to mixtures of two small molecule fluids, miscible binary polymer blends often exhibit two structural relaxation times and two glass transition temperatures. Qualitative explanations postulate phenomenological models of local concentration enhancements due to chain connectivity in ideal, fully miscible systems. We develop a quantitative theory that explains qualitative trends in the dynamics of real miscible polymer blends which are never ideal mixtures. The theory is a synthesis of the lattice cluster theory of blend thermodynamics, the generalized entropy theory for glass-formation in polymer materials, and the Kirkwood-Buff theory for concentration fluctuations in binary mixtures.

    11. Concerted Allosteric Transition Highlight

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

      combined use of x-ray crystallography and solution small angle x-ray scattering has enabled a research collaboration involving scientists from Boston College and SSRL to provide structural evidence supporting a 30-year old model accounting for the cooperative binding of ligands to allosteric proteins and enzymes - a function central to physiology and cellular processes. Over 30 years ago, two major models were developed to account for the cooperativity observed in oligomeric allosteric proteins

    12. Intermediate depth burial of classified transuranic wastes in arid alluvium

      SciTech Connect (OSTI)

      Cochran, J.R. [Sandia National Labs., Albuquerque, NM (United States). Environmental Risk and Decision Analysis Dept.; Crowe, B.M. [Los Alamos National Lab., NM (United States). Geologic Integration Group; Di Sanza, F. [Dept. of Energy, Las Vegas, NV (United States). Nevada Operations Office

      1999-04-01

      Intermediate depth disposal operations were conducted by the US Department of Energy (DOE) at the DOE`s Nevada Test Site (NTS) from 1984 through 1989. These operations emplaced high-specific activity low-level wastes (LLW) and limited quantities of classified transuranic (TRU) wastes in 37 m (120-ft) deep, Greater Confinement Disposal (GCD) boreholes. The GCD boreholes are 3 m (10 ft) in diameter and founded in a thick sequence of arid alluvium. The bottom 15 m (50 ft) of each borehole was used for waste emplacement and the upper 21 m (70 ft) was backfilled with native alluvium. The bottom of each GCD borehole is almost 200 m (650 ft) above the water table. The GCD boreholes are located in one of the most arid portions of the US, with an average precipitation of 13 cm (5 inches) per year. The limited precipitation, coupled with generally warm temperatures and low humidities results in a hydrologic system dominated by evapotranspiration. The US Environmental Protection Agency`s (EPA`s) 40 CFR 191 defines the requirements for protection of human health from disposed TRU wastes. This EPA standard sets a number of requirements, including probabilistic limits on the cumulative releases of radionuclides to the accessible environment for 10,000 years. The DOE Nevada Operations Office (DOE/NV) has contracted with Sandia National Laboratories (Sandia) to conduct a performance assessment (PA) to determine if the TRU wastes emplaced in the GCD boreholes complies with the EPA`s 40 CFR 191 requirements. This paper describes DOE`s actions undertaken to evaluate whether the TRU wastes in the GCD boreholes will, or will not, endanger human health. Based on preliminary modeling, the TRU wastes in the GCD boreholes meet the EPA`s requirements, and are, therefore, protective of human health.

    13. The structure, thermal expansion and phase transition properties of Ho{sub 2}Mo{sub 3−x}W{sub x}O{sub 12} (x = 0, 1.0, 2.0) solid solutions

      SciTech Connect (OSTI)

      Liu, X.Z.; Hao, L.J.; Wu, M.M.; Ma, X.B.; Chen, D.F.; Liu, Y.T.

      2015-10-15

      Graphical abstract: A polymorph with Gd{sub 2}Mo{sub 3}O{sub 12}-type structure (space group: Pba2) for negative thermal expansion material Ho{sub 2}Mo{sub 3}O{sub 12} is observed above 700 °C, this polymorphism could be effectively supressed by W-substiution for Mo, the give the temperature dependence of Pba2 phase contents for Ho{sub 2}Mo{sub 3−x}W{sub x}O{sub 12} (x = 0.0, 1.0, 2.0). - Highlights: • The solid solution Ho{sub 2}Mo{sub 3−x}W{sub x}O{sub 12} was investigated by in situ X-ray diffraction. • It is found that the substitution slightly influence thermal expansion property. • A polymorph of Ho{sub 2}Mo{sub 3}O{sub 12} with Pba2 space group was observed above 700 °C. • The W-substitution for Mo effectively suppresses this transformation. - Abstract: Three solid solutions of Ho{sub 2}Mo{sub 3−x}W{sub x}O{sub 12}(x = 0, 1.0, 2.0) were prepared by solid state reaction method, the temperature dependent in-situ X-ray diffraction and thermal analysis were performed to investigate their structure and thermal expansion. All samples have orthorhombic structure(space group Pbcn# 60) with negative thermal expansion at the room temperature. the substitution of W for Mo enlarges the lattice constant and slightly influences the negative thermal expansion. An irreversible phase transformation to the Pba2 phase(Tb{sub 2}Mo{sub 3}O{sub 12} structure) was observed at high temperature for Mo-rich samples. This ploymorphism could be effectively suppressed by the W-substitution for Mo, this phenomenon could be explained by the lower electronegativity of W{sup 6+} than Mo{sup 6+}.

    14. Comparison of bifurcation dynamics of turbulent transport models for the L-H transition

      SciTech Connect (OSTI)

      Weymiens, W. Blank, H. J. de; Hogeweij, G. M. D.; Paquay, S.

      2014-05-15

      In more than three decades, a large amount of models and mechanisms have been proposed to describe a very beneficial feature of magnetically confined fusion plasmas: the L-H transition. Bifurcation theory can be used to compare these different models based on their dynamical transition structure. In this paper, we employ bifurcation theory to distinguish two fundamentally different descriptions of the interaction between turbulence levels and sheared flows. The analytic bifurcation analysis characterises the parameter space structure of the transition dynamics. Herewith, in these models three dynamically different types of transitions are characterised, sharp transitions, oscillatory transitions, and smooth transitions. One of the two models has a very robust transition structure and is therefore likely to be more accurate for such a robust phenomenon as the L-H transition. The other model needs more fine-tuning to get non-oscillatory transitions. These conclusions from the analytic bifurcation analysis are confirmed by dedicated numerical simulations, with the newly developed code Bifurcator.

    15. SUBSIDY ENERGY EMPLOYEES TRANSIT (SEET)

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

      SUBSIDY ENERGY EMPLOYEES TRANSIT (SEET) Decrease in the Transit Subsidy Per The American Taxpayer Relief Act of 2012, the maximum amount for the Transit Subsidy is due to decrease from $245 to $130 a month. This change is scheduled to take effect on January 1, 2014. Outlined below are actions that you must take to purchase your fare for January 2014. SmarTrip less than $130.00 Per Month No Action Required SmarTrip greater than $130.00 Per Month Action Required SmarTrip Participants The new

    16. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation...

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

      PDF icon 44646-2.pdf More Documents & Publications SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary Evaluation Results SunLine Transit Agency Fuel Cell Transit ...

    17. Aerosol optical depth derived from solar radiometry observations at northern mid-latitude sites

      SciTech Connect (OSTI)

      Laulainen, N.S.; Larson, N.R.; Michalsky, J.J.; Harrison, L.C.

      1994-01-01

      Routine, automated solar radiometry observations began with the development of the Mobile Automated Scanning Photometer (MASP) and its installation at the Rattlesnake Mountain Observatory (RMO). We have introduced a microprocessor controlled rotating shadowband radiometer (RSR), both the single detector and the multi-filter/detector (MFRSR) versions to replace the MASP. The operational mode of the RSRs is substantially different than the MASP or other traditional sun-tracking radiometers, because, by virtue of the automated rotating shadowband, the total and diffuse irradiance on a horizontal plane are measured and the direct-normal component deduced through computation from the total and diffuse components by the self-contained microprocessor. Because the three irradiance components are measured using the same detector for a given wavelength, the calibration coefficients are identical for each component, thus reducing errors when comparing them. The MFRSR is the primary radiometric instrument in the nine-station Quantitative Links Network (QLN) established in the eastern United States in late 1991. Data from this network are being used to investigate how cloud- and aerosol-induced radiative effects vary in time and with cloud structure and type over a mid-latitude continental region. This work supports the DOE Quantitative Links Program to quantify linkages between changes in atmospheric composition and climate forcing. In this paper we describe the setup of the QLN and present aerosol optical depth results from the on-going measurements at PNL/RMO, as well as preliminary results from the QLN. From the time-series of data at each site, we compare seasonal variability and geographical differences, as well as the effect of the perturbation to the stratosphere by Mt. Pinatubo. Analysis of the wavelength dependence of optical depth also provides information on the evolution and changes in the size distribution of the aerosols.

    18. Office of Technology Transitions- Overview

      Broader source: Energy.gov [DOE]

      The following fact sheet provides an overview of the Office of Technology Transitions (OTT). The Department of Energy (DOE) is one of the largest supporters of technology transfer in the federal...

    19. Lab transitions employee giving campaigns

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

      Lab transitions employee giving campaigns Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Lab transitions employee giving campaigns This year's theme: "I Give Because..." November 1, 2013 Employee Giving Logo The theme for this year's employee giving campaigns Contact Community Programs Office Director Kurt Steinhaus Email Editor Linda Anderman Email During the past seven

    20. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report and

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

      Appendices | Department of Energy 44646-2.pdf (1.51 MB) More Documents & Publications SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary Evaluation Results SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report -- Appendices SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation Report -- Appendices

    1. Nanodisperse transition metal electrodes (NTME) for electrochemical cells

      DOE Patents [OSTI]

      Striebel, Kathryn A.; Wen, Shi-Jie

      2000-01-01

      Disclosed are transition metal electrodes for electrochemical cells using gel-state and solid-state polymers. The electrodes are suitable for use in primary and secondary cells. The electrodes (either negative electrode or positive electrode) are characterized by uniform dispersion of the transition metal at the nanoscale in the polymer. The transition metal moiety is structurally amorphous, so no capacity fade should occur due to lattice expansion/contraction mechanisms. The small grain size, amorphous structure and homogeneous distribution provide improved charge/discharge cycling performance, and a higher initial discharge rate capability. The cells can be cycled at high current densities, limited only by the electrolyte conductivity. A method of making the electrodes (positive and negative), and their usage in electrochemical cells are disclosed.

    2. Electronic structure of metallic glasses

      SciTech Connect (OSTI)

      Oelhafen, P.; Lapka, R.; Gubler, U.; Krieg, J.; DasGupta, A.; Guentherodt, H.J.; Mizoguchi, T.; Hague, C.; Kuebler, J.; Nagel, S.R.

      1981-01-01

      This paper is organized in six sections and deals with (1) the glassy transition metal alloys, their d-band structure, the d-band shifts on alloying and their relation to the alloy heat of formation (..delta..H) and the glass forming ability, (2) the glass to crystal phase transition viewed by valence band spectroscopy, (3) band structure calculations, (4) metallic glasses prepared by laser glazing, (5) glassy normal metal alloys, and (6) glassy hydrides.

    3. Energy Transition Initiative Energy Scenario Tool | Department...

      Energy Savers [EERE]

      Energy Transition Initiative Energy Scenario Tool Energy Transition Initiative Energy Scenario Tool The ETI Energy Scenario Tool helps communities analyze different pathways to ...

    4. Low Carbon Transition Unit | Open Energy Information

      Open Energy Info (EERE)

      Transition Unit Jump to: navigation, search Name Low Carbon Transition Unit AgencyCompany Organization Danish Government Partner Danish Ministry of Climate, Energy and Buildings;...

    5. Energy Transition Model | Open Energy Information

      Open Energy Info (EERE)

      Transition Model Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Energy Transition Model AgencyCompany Organization: Quintel Intelligence Sector: Energy Topics:...

    6. Technology Transitions Facilities Database | Department of Energy

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

      Technology Transitions Facilities Database Technology Transitions Facilities Database Type* Laboratory Name Facilities DataBase The DOE National Laboratories maintain cutting-edge ...

    7. Transition Zone Geothermal Region | Open Energy Information

      Open Energy Info (EERE)

      Unknown Planned Capacity 1 Geothermal Areas within the Transition Zone Geothermal Region Energy Generation Facilities within the Transition Zone Geothermal Region Geothermal Power...

    8. Office of Technology Transitions | Department of Energy

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

      Turning Ideas into Impact: The Energy Department's Office of Technology Transitions Turning Ideas into Impact: The Energy Department's Office of Technology Transitions Amazing...

    9. Dewetting Transitions on Superhydrophobic Surfaces: When are...

      Office of Scientific and Technical Information (OSTI)

      Dewetting Transitions on Superhydrophobic Surfaces: When are Wenzel Drops Reversible? Citation Details In-Document Search Title: Dewetting Transitions on Superhydrophobic Surfaces: ...

    10. Solitosynthesis induced phase transitions (Journal Article) ...

      Office of Scientific and Technical Information (OSTI)

      Solitosynthesis induced phase transitions Citation Details In-Document Search Title: Solitosynthesis induced phase transitions Authors: Pearce, Lauren Publication Date: 2012-06-19 ...

    11. Solitosynthesis induced phase transitions (Journal Article) ...

      Office of Scientific and Technical Information (OSTI)

      Solitosynthesis induced phase transitions Prev Next Title: Solitosynthesis induced phase transitions Authors: Pearce, Lauren Publication Date: 2012-06-19 OSTI Identifier: ...

    12. Phase transitions in insertion electrodes for lithium batteries

      SciTech Connect (OSTI)

      Thackeray, M. M.

      2000-02-02

      Phase transitions that occur during lithium insertion into layered and framework structures are discussed in the context of their application as positive and negative electrodes in lithium-ion batteries. The discussion is focused on the two-dimensional structures of graphite, LiNi{sub 1{minus}x}M{sub x}O{sub 2} (M = Co, Ti and Mg), and Li{sub 1.2}V{sub 3}O{sub 8}; examples of framework structures with a three-dimensional interstitial space for Li{sup +}-ion transport include the spinel oxides and intermetallic compounds with zinc-blende-type structures. The phase transitions are discussed in terms of their tolerance to lithium insertion and extraction and to the chemical stability of the electrodes in the cell environment.

    13. Fuel Cell Transit Bus Coordination and Evaluation Plan California...

      Energy Savers [EERE]

      Transit Bus Coordination and Evaluation Plan California Fuel Cell Transit Evaluation Team Fuel Cell Transit Bus Coordination and Evaluation Plan California Fuel Cell Transit ...

    14. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

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

      Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print Wednesday, 28 September 2005 00:00 The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions.

    15. The phase transition in VO2 probed using x-ray, visible and infrared

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

      radiations phase transition in VO2 probed using x-ray, visible and infrared radiations The phase transition in VO2 probed using x-ray, visible and infrared radiations Print Thursday, 18 February 2016 10:48 The nearly simultaneous Mott (electronic) and Peierls (structural) transitions in vanadium dioxide are of significant scientific interest and have tremendous technological promise in computing, memory, optics, and micromechanics. The cover features nanoscale-resolution maps of the Mott and

    16. On the nature of the magnetocaloric effect of the first-order magnetostructural transition

      SciTech Connect (OSTI)

      Gschneidner, Karl A. Jr; Mudryk, Yaroslav; Pecharsky, Vitalij K.

      2012-01-10

      Methods were developed to determine the structural entropy contribution to the total isothermal entropy change of materials which undergo a magnetostructural first-order phase transition. The structural entropies range from 4.5 to 45 J kg#2;1 K#2;1 and are proportional to the volume differences of the phases involved in the transition. This correlation allows one to predict new giant magnetocaloric effect materials from crystallographic data. There is a critical magnetic field which must be exceeded to drive the structural transition to completion.

    17. Polyamorphous transition in amorphous fullerites C{sub 70}

      SciTech Connect (OSTI)

      Borisova, P. A.; Agafonov, S. S.; Glazkov, V. P.; D'yakonova, N. P.; Somenkov, V. A.

      2011-12-15

      Samples of amorphous fullerites C{sub 70} have been obtained by mechanical activation (grinding in a ball mill). The structure of the samples has been investigated by neutron and X-ray diffraction. The high-temperature (up to 1200 Degree-Sign C) annealing of amorphous fullerites revealed a polyamorphous transition from molecular to atomic glass, which is accompanied by the disappearance of fullerene halos at small scattering angles. Possible structural versions of the high-temperature amorphous phase are discussed.

    18. The change of microstructure and thermal properties in ion irradiated carbon nanotube mats as a function of ion penetration depth

      SciTech Connect (OSTI)

      Aitkaliyeva, A. [Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States)] [Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States); Shao, L. [Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States) [Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States); Department of Nuclear Engineering, Texas A and M University, College Station, Texas 77843 (United States)

      2013-02-11

      A stack of three carbon nanotube (CNT) mats was irradiated with 3 MeV He ions. The change in structural and thermal properties of individual mats as a function of ion penetration depth was characterized using electron microscopy and laser flash techniques. Ion irradiation can enhance thermal conductivity of the mats by introducing inter-tube displacements, which improve phonon transport across adjacent nanotubes. The enhancement, however, is reduced at higher damage levels due to the increasing phonon-defect scattering within the tubes. This study demonstrates the feasibility of using ion irradiation to manipulate thermal transport in carbon nanotubes.

    19. PoroTomo Subtask 6.8 - Brady Well Coordinates and Observation Sensor Depths

      Office of Scientific and Technical Information (OSTI)

      (Dataset) | SciTech Connect 8 - Brady Well Coordinates and Observation Sensor Depths Citation Details In-Document Search Title: PoroTomo Subtask 6.8 - Brady Well Coordinates and Observation Sensor Depths Contains metadata associated with the wells used in the 2016 Spring Campaign led partially by UW - Madison, LBNL, and LLNL scientists. Included with the well coordinates are the depths to the pressure sensors used in observation and pumping wells. Read me files are included for each .csv

    20. Practical Analysis of materials with depth varying compositions using FT-IR photoacoustic spectroscopy (PAS)

      SciTech Connect (OSTI)

      J.F. McClelland; R.W. Jones; Siquan Luo

      2004-09-30

      FT-IR photoacoustic spectroscopy (PAS) is discussed as a nondestructive method to probe the molecular composition of materials versus depth on the basis of the analysis of layers of experimentally controllable thickness, which are measured from the sample surface to depths of some tens of micrometers, depending on optical and thermal properties. Computational methods are described to process photoacoustic amplitude and phase spectra for both semi-quantitative and quantitative depth analyses. These methods are demonstrated on layered and gradient samples.

    1. CONNECTING TRANSITIONS IN GALAXY PROPERTIES TO REFUELING

      SciTech Connect (OSTI)

      Kannappan, Sheila J.; Stark, David V.; Eckert, Kathleen D.; Moffett, Amanda J.; Norris, Mark A.; Weinberg-Wolf, Jennifer; Wei, Lisa H.; Fabricant, Daniel G.; Pisano, D. J.; Baker, Andrew J.; Vogel, Stuart N.; Laine, Seppo; Jogee, Shardha; Lepore, Natasha; Hough, Loren E.

      2013-11-01

      We relate transitions in galaxy structure and gas content to refueling, here defined to include both the external gas accretion and the internal gas processing needed to renew reservoirs for star formation. We analyze two z = 0 data sets: a high-quality ∼200 galaxy sample (the Nearby Field Galaxy Survey, data release herein) and a volume-limited ∼3000 galaxy sample with reprocessed archival data. Both reach down to baryonic masses ∼10{sup 9} M{sub ☉} and span void-to-cluster environments. Two mass-dependent transitions are evident: (1) below the 'gas-richness threshold' scale (V ∼ 125 km s{sup –1}), gas-dominated quasi-bulgeless Sd-Im galaxies become numerically dominant; while (2) above the 'bimodality' scale (V ∼ 200 km s{sup –1}), gas-starved E/S0s become the norm. Notwithstanding these transitions, galaxy mass (or V as its proxy) is a poor predictor of gas-to-stellar mass ratio M{sub gas}/M{sub *}. Instead, M{sub gas}/M{sub *} correlates well with the ratio of a galaxy's stellar mass formed in the last Gyr to its preexisting stellar mass, such that the two ratios have numerically similar values. This striking correspondence between past-averaged star formation and current gas richness implies routine refueling of star-forming galaxies on Gyr timescales. We argue that this refueling underlies the tight M{sub gas}/M{sub *} versus color correlations often used to measure 'photometric gas fractions'. Furthermore, the threshold and bimodality scale transitions reflect mass-dependent demographic shifts between three refueling regimes—accretion-dominated, processing-dominated, and quenched. In this picture, gas-dominated dwarfs are explained not by inefficient star formation but by overwhelming gas accretion, which fuels stellar mass doubling in ∼<1 Gyr. Moreover, moderately gas-rich bulged disks such as the Milky Way are transitional, becoming abundant only in the narrow range between the threshold and bimodality scales.

    2. SunLine Transit Agency Hydrogen-Powered Transit Buses: Evaluation Results

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

      Update | Department of Energy Hydrogen-Powered Transit Buses: Evaluation Results Update SunLine Transit Agency Hydrogen-Powered Transit Buses: Evaluation Results Update This report provides an update on the evaluation results for hydrogen and CNG-fueled buses opertating at SunLine Transit Agency in California. 42080.pdf (1.02 MB) More Documents & Publications SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary Evaluation Results SunLine Transit Agency Hydrogen-Powered

    3. SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary

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

      Evaluation Results | Department of Energy Agency, Hydrogen-Powered Transit Buses: Preliminary Evaluation Results SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary Evaluation Results This paper provides preliminary results from an evaluation by DOE's National Renewable Energy Laboratory of hydrogen-powered transit buses at SunLine Transit Agency. 41001.pdf (1.38 MB) More Documents & Publications SunLine Transit Agency Hydrogen-Powered Transit Buses: Evaluation Results

    4. Image of the Moho across the continent-ocean transition, US east coast

      SciTech Connect (OSTI)

      Holbrook, W.S.; Purdy, G.M. ); Reiter, E.C.; Toksoez, M.N. )

      1992-03-01

      Strong wide-angle reflections from the Moho were recorded by ocean-bottom seismic instruments during the 1988 Carolina Trough multichannel seismic experiment, in an area where the Moho is difficult to detect with vertical-incidence seismic data. Prestack depth migration of these reflections has enabled the construction of a seismic image of the Moho across the continent-ocean transition of a sedimented passive margin. The Moho rises across the margin at a slope of 10{degree}-12{degree}, from a depth of about 33 km beneath the continental shelf to 20 km beneath the outer rise. This zone of crustal thinning defines a distinct, 60-70-km-wide continent-ocean transition zone. The authors interpret the Moho in the Carolina Trough as a Jurassic feature, formed by magmatic intrusion and underplating during the rifting of Pangea.

    5. DOE Transition Documents - 2008 | Department of Energy

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

      Transition Documents - 2008 DOE Transition Documents - 2008 Following are the DOE Transition Documents - 2008 Files in PDF format 2008_Transition_Corporate_Overview_Book_One.pdf (8.1 MB) 2008_Transition_Important_Issues_Book_Two.pdf (6.85 MB) 2008_Transition_Program_Details_Book_Three.pdf (41.97 MB) 2008_Transition_Budget_Details_Book_Four.pdf (10.21 MB) Authorize_Changes_Contractor_Work_Force_Restructuring_Policy.pdf (137.48 KB) Compilation Congressional Correspondence, January 1, 2008 throught

    6. LTS Transition and Timeline - Hanford Site

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

      Transition and Timeline About Us Hanford Cultural Resources LTS Home Page LTS Project Management LTS Transition and Timeline LTS Execution LTS Background LTS Information Management LTS Fact Sheets / Briefings LTS In The News LTS Related Links LTS Contact Us LTS Transition and Timeline Email Email Page | Print Print Page | Text Increase Font Size Decrease Font Size Transition Map Please click on area to see more information Transition Map Segment 1 : Area Size 18,161 acres, 28 sq mi Segment 2

    7. Energy Transition Initiative | Department of Energy

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

      Energy Transition Initiative Energy Transition Initiative Energy Transition Initiative Through the Energy Transition Initiative (ETI), the U.S. Department of Energy and its partners work with government entities and other stakeholders to establish a long-term energy vision and successfully implement energy efficiency and renewable energy solutions. ETI provides a proven framework and technical resources and tools to help islands, states, and cities transition to a clean energy economy and

    8. DEPTH-CHARGE static and time-dependent perturbation/sensitivity system for nuclear reactor core analysis. Revision I. [DEPTH-CHARGE code

      SciTech Connect (OSTI)

      White, J.R.

      1985-04-01

      This report provides the background theory, user input, and sample problems required for the efficient application of the DEPTH-CHARGE system - a code black for both static and time-dependent perturbation theory and data sensitivity analyses. The DEPTH-CHARGE system is of modular construction and has been implemented within the VENTURE-BURNER computational system at Oak Ridge National Laboratory. The DEPTH module (coupled with VENTURE) solves for the three adjoint functions of Depletion Perturbation Theory and calculates the desired time-dependent derivatives of the response with respect to the nuclide concentrations and nuclear data utilized in the reference model. The CHARGE code is a collection of utility routines for general data manipulation and input preparation and considerably extends the usefulness of the system through the automatic generation of adjoint sources, estimated perturbed responses, and relative data sensitivity coefficients. Combined, the DEPTH-CHARGE system provides, for the first time, a complete generalized first-order perturbation/sensitivity theory capability for both static and time-dependent analyses of realistic multidimensional reactor models. This current documentation incorporates minor revisions to the original DEPTH-CHARGE documentation (ORNL/CSD-78) to reflect some new capabilities within the individual codes.

    9. Method for determining depth and shape of a sub-surface conductive object

      DOE Patents [OSTI]

      Lee, D.O.; Montoya, P.C.; Wayland, Jr.

      1984-06-27

      The depth to and size of an underground object may be determined by sweeping a controlled source audio magnetotelluric (CSAMT) signal and locating a peak response when the receiver spans the edge of the object. The depth of the object is one quarter wavelength in the subsurface media of the frequency of the peak. 3 figures.

    10. Two weight system for measuring depth and sediment in slurry-supported excavations

      SciTech Connect (OSTI)

      Deming, P.; Good, D.

      1999-07-01

      This paper describes a two weight system using bar and flat shaped weights for measuring depth and detecting sediment at the bottom of slurry-supported excavations. Currently there are no standard depth measurement weights or methods for reliably identifying bottom sediment. Two weights and a procedural system for using the weights is described. Details suitable for manufacture are provided.

    11. Using the depth-velocity-size diagram to interpret equilibrium bed configurations in river flows

      SciTech Connect (OSTI)

      Southard, J.B. (Massachusetts Institute of Technology, Cambridge, MA (USA))

      1990-05-01

      Data from flume studies that report equilibrium bed configuration as well as water temperature, flow depth, flow velocity, and sediment size were used to develop the best approximation to the relationships among the various bed phases (ripples, dunes, lower regime plane bed, upper regime plane bed, and antidunes) in a three-axis graph (depth-velocity-size diagram) with dimensionless measures of mean flow depth, mean flow velocity, and sediment size along the axis. Relationships are shown in a series of depth-velocity and velocity-size sections through the diagram. Boundaries between bed-phase stability fields are drawn as surfaces that minimize, misplacement of data points. A large subset of the data, for which reliable values of bed shear stress are reported, was also used to represent the stability relationships in a graph of dimensionless boundary shear stress against dimensionless sediment size, but with results less useful for fluvial flow interpretation. The diagram covers about one order of magnitude in flow depth. To be useful for river flows, the diagram must be extrapolated in flow depth by about one more order of magnitude, but this is not a serious problem for approximate work. The depth-velocity-size diagram permits prediction of equilibrium bed configuration in river flows when the approximate flow depth and mean flow velocity are known. Because the diagram is essentially dimensionless, the effect of water temperature (via the fluid viscosity) on the bed configuration is easily accounted for by use of the diagram.

    12. FTA- SunLine Transit Agency- Final Report

      Broader source: Energy.gov [DOE]

      Final Report on the Federal Transit Administration, SunLine Transit Agency Cooperative Agreement (Part One)

    13. Transition metal sulfide loaded catalyst

      DOE Patents [OSTI]

      Maroni, Victor A.; Iton, Lennox E.; Pasterczyk, James W.; Winterer, Markus; Krause, Theodore R.

      1994-01-01

      A zeolite based catalyst for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C.sub.2 + hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

    14. Stress relief of transition zones

      SciTech Connect (OSTI)

      Woodward, J.; van Rooyen, D.

      1984-01-01

      This paper considers the problem of intergranular stress corrosion cracking, initiated on the primary side, in the expansion transition region of roller expanded Alloy 600 tubing. In general it is believed that residual stresses, arising from the expansion process, are the cause of the problem. The work reported here concentrated on the identification of an optimal, in-situ stress relief treatment.

    15. Transition metal sulfide loaded catalyst

      DOE Patents [OSTI]

      Maroni, V.A.; Iton, L.E.; Pasterczyk, J.W.; Winterer, M.; Krause, T.R.

      1994-04-26

      A zeolite-based catalyst is described for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C[sub 2]+ hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

    16. Evolution of Nuclear Observables in the Spherical-Deformed Phase Transition and the Interacting Boson Model

      SciTech Connect (OSTI)

      Zamfir, N.V.; McCutchan, E.A.; Casten, R.F.

      2004-09-13

      We discuss the empirical evolution of structure in the spherical-deformed phase transition region in the context of the behavior of basic structural signatures in the IBA symmetry triangle. The main signatures of a phase/shape transition are a sharp increase in R{sub 4/2} {identical_to} E(4{sub 1}{sup +})/E(2{sub 1}{sup +}) and minima in E(0{sub 2}{sup +}) and E(2{sub {gamma}}{sup +})

    17. Understanding heat and groundwater flow through continental flood basalt provinces: insights gained from alternative models of permeability/depth relationships for the Columbia Plateau, USA

      SciTech Connect (OSTI)

      Burns, Erick R.; Williams, Colin F.; Ingebritsen, Steven E.; Voss, Clifford I.; Spane, Frank A.; DeAngelo, Jacob

      2015-02-01

      Heat-flow mapping of the western USA has identified an apparent low-heat-flow anomaly coincident with the Columbia Plateau Regional Aquifer System, a thick sequence of basalt aquifers within the Columbia River Basalt Group (CRBG). A heat and mass transport model (SUTRA) was used to evaluate the potential impact of groundwater flow on heat flow along two different regional groundwater flow paths. Limited in situ permeability (k) data from the CRBG are compatible with a steep permeability decrease (approximately 3.5 orders of magnitude) at 600–900 m depth and approximately 40°C. Numerical simulations incorporating this permeability decrease demonstrate that regional groundwater flow can explain lower-than-expected heat flow in these highly anisotropic (kx/kz ~ 104) continental flood basalts. Simulation results indicate that the abrupt reduction in permeability at approximately 600 m depth results in an equivalently abrupt transition from a shallow region where heat flow is affected by groundwater flow to a deeper region of conduction-dominated heat flow. Most existing heat-flow measurements within the CRBG are from shallower than 600 m depth or near regional groundwater discharge zones, so that heat-flow maps generated using these data are likely influenced by groundwater flow. Substantial k decreases at similar temperatures have also been observed in the volcanic rocks of the adjacent Cascade Range volcanic arc and at Kilauea Volcano, Hawaii, where they result from low-temperature hydrothermal alteration.

    18. A SUPER-EARTH TRANSITING A NAKED-EYE STAR

      SciTech Connect (OSTI)

      Winn, Joshua N.; Matthews, Jaymie M.; Kallinger, Thomas; Dragomir, Diana; Dawson, Rebekah I.; Holman, Matthew J.; Sasselov, Dimitar; Fabrycky, Daniel; Guenther, David B.; Moffat, Anthony F. J.; Rowe, Jason F.; Rucinski, Slavek

      2011-08-10

      We have detected transits of the innermost planet 'e' orbiting 55 Cnc (V = 6.0), based on two weeks of nearly continuous photometric monitoring with the MOST space telescope. The transits occur with the period (0.74 days) and phase that had been predicted by Dawson and Fabrycky, and with the expected duration and depth for the crossing of a Sun-like star by a hot super-Earth. Assuming the star's mass and radius to be 0.963{sup +0.051}{sub -0.029} M{sub sun} and 0.943 {+-} 0.010 R{sub sun}, the planet's mass, radius, and mean density are 8.63 {+-} 0.35 M{sub +}, 2.00 {+-} 0.14 R{sub +}, and 5.9{sup +1.5}{sub -1.1} g cm{sup -3}, respectively. The mean density is comparable to that of Earth, despite the greater mass and consequently greater compression of the interior of 55 Cnc e. This suggests a rock-iron composition supplemented by a significant mass of water, gas, or other light elements. Outside of transits, we detected a sinusoidal signal resembling the expected signal due to the changing illuminated phase of the planet, but with a full range (168 {+-} 70 ppm) too large to be reflected light or thermal emission. This signal has no straightforward interpretation and should be checked with further observations. The host star of 55 Cnc e is brighter than that of any other known transiting planet, which will facilitate future investigations.

    19. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation...

      Energy Savers [EERE]

      Fifth Evaluation Report SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report This report describes operations at SunLine Transit Agency for a prototype fuel cell ...

    20. Direct measurement of the alpha-epsilon transition stress and kinetics for shocked iron

      SciTech Connect (OSTI)

      Jensen, Brian J; Gray, Ill, George T; Hixson, Robert S

      2009-01-01

      Iron undergoes a polymorphic phase transformation from alpha phase (bcc) to the epsilon phase (hcp) when compressed to stresses exceeding 13 CPa. Bccause the epsilon phase is denser than the alpha phase, a single shock wave is unstable and breaks up into an elastic wave, a plastic wave, and a phase transition wave. Examination of this structured wave coupled with various phase transformation models has been used to indirectly examine the transition kinetics. Recently, multimillion atom simulations (molecular dynamics) have been used to examine the shock-induced transition in single crystal iron illustrating an orientation dependence of the transition stress, mechanisms, and kinetics. The objective of the current work was to perform plate impact experiments to examine the shock-response of polycrystalline and single crystal iron with nanosecond resolution for impact stresses spanning the {alpha} - {epsilon} transition. The current data reveal an orientation dependence of the transition stress coupled with a transition time that is nonlinearly dependent on the impact stress with a duration ranging from picoseconds to hundreds of nanoseconds. The higher transition stress for iron[100] is in agreement with the predictions from MD calculations that describe an orientation dependence of the transition stress. However, MD calculations do not capture the complexity of the continuum states achieved or the transition kinetics. Further results and implications are discussed in this paper.

    1. Origin of thickness dependence of structural phase transition...

      Office of Scientific and Technical Information (OSTI)

      Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA Materials ... Oak Ridge, Tennessee 37831, USA X-Ray Science Division, Advanced Photon Source, ...

    2. Coupled ion Binding and Structural Transitions Along the Transport...

      Office of Scientific and Technical Information (OSTI)

      binding primes the transport domain to accept its substrate and triggers extracellular gate opening, which prevents inward domain translocation until substrate binding takes place. ...

    3. Following a Structural Phase Transition in Real Time with Atomic...

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

      high brightness, ultrafast x-ray sources such as the Linac Coherent Light Source (LCLS). ... disordering results from inertial motion on a laser softened potential energy surface. ...

    4. Probing the surface structure of divalent transition metals using...

      Office of Scientific and Technical Information (OSTI)

      Authors: Mason, H E ; Harley, S J ; Maxwell, R S ; Carroll, S A Publication Date: 2011-12-07 OSTI Identifier: 1107317 Report Number(s): LLNL-JRNL-520237 DOE Contract Number: ...

    5. Structural and magnetic phase transitions near optimal superconductivi...

      Office of Scientific and Technical Information (OSTI)

      results suggest that AF order in BaFe2(As1-xPx)2 disappears in a weakly first order fashion near optimal superconductivity, much like the electron-doped iron pnictides with an ...

    6. Surface Domain Structures and Mesoscopic Phase Transition in...

      Office of Scientific and Technical Information (OSTI)

      discovery of ferroelectric relaxors by the Smolensky group, the most basic aspect of these materials the existence and nature of order parameter has not been understood thoroughly. ...

    7. Energy level structure and transition probabilities in the spectra...

      Office of Scientific and Technical Information (OSTI)

      H.M. 74 ATOMIC AND MOLECULAR PHYSICS; 36 MATERIALS SCIENCE; DYSPROSIUM IONS; ENERGY LEVELS; ERBIUM IONS; EUROPIUM IONS; GADOLINIUM IONS; HOLMIUM IONS; LANTHANUM...

    8. ANL-78-XX-95 Energy Level Structure and Transition Probabilities

      Office of Scientific and Technical Information (OSTI)

      III. Treatment of Experimental Data 8 Fig. 2. Crystal-field Parameters for Ln 3+ :LaCl 3 and Ln 3+ :LaF 3 13 IV. Energy Level Correlations - Survey of Experimental Data 14 1. f 2 ...

    9. Structural Flexibility and Alloying in Ultrathin Transition-Metal...

      Office of Scientific and Technical Information (OSTI)

      Citation Details In-Document Search This content will become ... theory (DFT), we report that TMC nanowires have ... Type: Accepted Manuscript Journal Name: ACS Nano Additional ...

    10. Terahertz spectroscopy of two-dimensional subwavelength plasmonic structures

      SciTech Connect (OSTI)

      Azad, Abul K; Chen, Houtong; Taylor, Antoinette; O' Hara, John F; Han, Jiaguang; Lu, Xinchao; Zhang, Weili

      2009-01-01

      The fascinating properties of plasmonic structures have had significant impact on the development of next generation ultracompact photonic and optoelectronic components. We study two-dimensional plasmonic structures functioning at terahertz frequencies. Resonant terahertz response due to surface plasmons and dipole localized surface plasmons were investigated by the state-of-the-art terahertz time domain spectroscopy (THz-TDS) using both transmission and reflection configurations. Extraordinary terahertz transmission was demonstrated through the subwavelength metallic hole arrays made from good conducting metals as well as poor metals. Metallic arrays m!lde from Pb, generally a poor metal, and having optically thin thicknesses less than one-third of a skin depth also contributed in enhanced THz transmission. A direct transition of a surface plasmon resonance from a photonic crystal minimum was observed in a photo-doped semiconductor array. Electrical controls of the surface plasmon resonances by hybridization of the Schottkey diode between the metallic grating and the semiconductor substrate are investigated as a function of the applied reverse bias. In addition, we have demonstrated photo-induced creation and annihilation of surface plasmons with appropriate semiconductors at room temperature. According to the Fano model, the transmission properties are characterized by two essential contributions: resonant excitation of surface plasmons and nonresonant direct transmission. Such plasmonic structures may find fascinating applications in terahertz imaging, biomedical sensing, subwavelength terahertz spectroscopy, tunable filters, and integrated terahertz devices.

    11. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report and

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

      Appendices | Department of Energy This is the fourth evaluation report for this site, and it describes results and experiences from April 2008 through October 2008. 44646-1.pdf (641.2 KB) More Documents & Publications SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation Report and Appendices SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary Evaluation Results

    12. New York City Transit Hybrid and CNG Transit Buses: Interim Evaluation Results

      SciTech Connect (OSTI)

      Chandler, K.; Eberts, E.; Eudy, L.

      2006-01-01

      This report focuses on the evaluation of compressed natural gas (CNG) and diesel hybrid electric bus propulsion systems in New York City Transit's transit buses.

    13. SunLine Transit Agency, Hydrogen Powered Transit Buses: Preliminary Evaluation Results

      SciTech Connect (OSTI)

      Chandler, K.; Eudy, L.

      2007-02-01

      This paper provides preliminary results from an evaluation by DOE's National Renewable Energy Laboratory of hydrogen-powered transit buses at SunLine Transit Agency.

    14. SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary...

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

      This paper provides preliminary results from an evaluation by DOE's National Renewable Energy Laboratory of hydrogen-powered transit buses at SunLine Transit Agency. 41001.pdf ...

    15. Preliminary 3d depth migration of a network of 2d seismic lines for fault

      Office of Scientific and Technical Information (OSTI)

      imaging at a Pyramid Lake, Nevada geothermal prospect (Conference) | SciTech Connect Preliminary 3d depth migration of a network of 2d seismic lines for fault imaging at a Pyramid Lake, Nevada geothermal prospect Citation Details In-Document Search Title: Preliminary 3d depth migration of a network of 2d seismic lines for fault imaging at a Pyramid Lake, Nevada geothermal prospect Roxanna Frary, John N. Louie, Sathish Pullammanappallil, Amy Eisses, 2011, Preliminary 3d depth migration of a

    16. Electronic transitions of palladium dimer

      SciTech Connect (OSTI)

      Qian, Yue; Ng, Y. W.; Chen, Zhihua; Cheung, A. S.-C., E-mail: hrsccsc@hku.hk [Department of Chemistry, The University of Hong Kong, Pokfulam Road (Hong Kong)

      2013-11-21

      The laser induced fluorescence spectrum of palladium dimer (Pd{sub 2}) in the visible region between 480 and 700 nm has been observed and analyzed. The gas-phase Pd{sub 2} molecule was produced by laser ablation of palladium metal rod. Eleven vibrational bands were observed and assigned to the [17.1] {sup 3}II{sub g} - X{sup 3}?{sub u}{sup +} transition system. The bond length (r{sub o}) and vibrational frequency (?G{sub 1/2}) of the ground X{sup 3}?{sub u}{sup +} state were determined to be 2.47(4) and 211.4(5) cm{sup ?1}, respectively. A molecular orbital energy level diagram was used to understand the observed ground and excited electronic states. This is the first gas-phase experimental investigation of the electronic transitions of Pd{sub 2}.

    17. Articulated transition duct in turbomachine

      SciTech Connect (OSTI)

      Flanagan, James Scott; McMahan, Kevin Weston; LeBegue, Jeffrey Scott; Pentecost, Ronnie Ray

      2014-04-29

      Turbine systems are provided. A turbine system includes a transition duct comprising an inlet, an outlet, and a duct passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The duct passage includes an upstream portion and a downstream portion. The upstream portion extends from the inlet between an inlet end and an aft end. The downstream portion extends from the outlet between an outlet end and a head end. The turbine system further includes a joint coupling the aft end of the upstream portion and the head end of the downstream portion together. The joint is configured to allow movement of the upstream portion and the downstream portion relative to each other about or along at least one axis.

    18. Fast flux test facility, transition project plan

      SciTech Connect (OSTI)

      Guttenberg, S.

      1994-11-15

      The FFTF Transition Project Plan, Revision 1, provides changes and project baseline for the deactivation activities necessary to transition the FFTF to a radiologically and industrially safe shutdown condition.

    19. SEP Program Transition Tables | Department of Energy

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

      Transition Tables SEP Program Transition Tables The Program Transition Tables provide information concerning the level of effort required to move from a traditional, industrial incentive program to Strategic Energy Management, ISO 50001, or SEP. Both the customers' and utility program administrators' perspectives are considered. Utilities and PAs can use these detailed tables to understand and develop estimates of scope, resources, and realistic implementation timelines. View Program Transition

    20. Contact Technology Transitions | Department of Energy

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

      Contact Technology Transitions Contact Technology Transitions Please use this form to send us your comments, report problems, and/or ask questions about information on the Office of Technology Transition website. All entries on the form will go to the Office of Technology Transitions at the Department of Energy. If you wish to contact a specific laboratory, please do so directly on this page. Your Email Message Here * CAPTCHA This question is for testing whether you are a human visitor and to

    1. Recommendation 198: Establish a site transition process

      Broader source: Energy.gov [DOE]

      The ORSSAB recommends DOE Establish a Site Transition Process Upon Completion of Remediation at Ongoing Mission Sites.

    2. Hydrogen Policy and Analyzing the Transition

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

      Policy and Analyzing the Transition Paul N. Leiby, David L. Greene, Zhenhong Lin, David Bowman, Sujit Das Oak Ridge National Laboratory November 16, 2009 Presented at the Workshop, "Delivering Renewable Hydrogen," NREL/CaFCP, Palm Springs, CA 2 Overview: Hydrogen Policy and Analyzing the Transition * Some lessons learned from analyzing fuel transitions - Find barriers to transitions significant, but progress being made - Review work by DOE-sponsored team, highlighting key factors *

    3. Method of varying a physical property of a material through its depth

      SciTech Connect (OSTI)

      Daniel, Claus

      2015-04-21

      A method is disclosed for varying a mechanical property of a material at two depths. The method involves the application of at least two laser pulses of different durations. The method involves a determination of the density of the material from the surface to each depth, a determination of the heat capacity of the material from the surface to each depth, and a determination of the thermal conductivity of the material from the surface to each depth. Each laser pulse may affect the density, heat capacity, and thermal conductivity of the material, so it may be necessary to re-evaluate those parameters after each laser pulse and prior to the next pulse. The method may be applied to implantation materials to improve osteoblast and osteoclast activity.

    4. Depth Profiling of SiC Lattice Damage Using Micro-Raman Spectroscopy...

      Office of Scientific and Technical Information (OSTI)

      (OAS) was used for establishing the opacity (and therefore the probing depth) of the damaged layer to the 632.8 nm wavelength of the He-Ne laser used for CMR throughout this study. ...

    5. Vehicle Technologies Office Merit Review 2014: Advanced Technology Vehicle Lab Benchmarking- Level 2 (in-depth)

      Broader source: Energy.gov [DOE]

      Presentation given by Argonne National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about level 2 (in-depth...

    6. Depth-dependent ordering, two-length-scale phenomena, and crossover...

      Office of Scientific and Technical Information (OSTI)

      a skin layer with defects Citation Details In-Document Search Title: Depth-dependent ordering, two-length-scale phenomena, and crossover behavior in a crystal featuring a skin ...

    7. Depth Profile of Uncompensated Spins in an Exchange-Bias System

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

      resonant x-ray scattering and polarized-neutron reflectometry to determine the depth-dependent magnetization in an exchange-biased sample. These results provide atomic-level ...

    8. Depth Profile of Uncompensated Spins in an Exchange-Bias System

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

      Depth Profile of Uncompensated Spins in an Exchange-Bias System Print The phenomenon known as exchange bias at the interface between a ferromagnet and an antiferromagnet is currently a subject of intense research because of its applications in the magnetic recording and read-head industries. An international collaboration headed by researchers from the University of California, San Diego, has used resonant x-ray scattering and polarized-neutron reflectometry to determine the depth-dependent

    9. Depth Profile of Uncompensated Spins in an Exchange-Bias System

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

      Depth Profile of Uncompensated Spins in an Exchange-Bias System Print The phenomenon known as exchange bias at the interface between a ferromagnet and an antiferromagnet is currently a subject of intense research because of its applications in the magnetic recording and read-head industries. An international collaboration headed by researchers from the University of California, San Diego, has used resonant x-ray scattering and polarized-neutron reflectometry to determine the depth-dependent

    10. Depth Profile of Uncompensated Spins in an Exchange-Bias System

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

      Depth Profile of Uncompensated Spins in an Exchange-Bias System Print The phenomenon known as exchange bias at the interface between a ferromagnet and an antiferromagnet is currently a subject of intense research because of its applications in the magnetic recording and read-head industries. An international collaboration headed by researchers from the University of California, San Diego, has used resonant x-ray scattering and polarized-neutron reflectometry to determine the depth-dependent

    11. Depth Profile of Uncompensated Spins in an Exchange-Bias System

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

      Depth Profile of Uncompensated Spins in an Exchange-Bias System Print The phenomenon known as exchange bias at the interface between a ferromagnet and an antiferromagnet is currently a subject of intense research because of its applications in the magnetic recording and read-head industries. An international collaboration headed by researchers from the University of California, San Diego, has used resonant x-ray scattering and polarized-neutron reflectometry to determine the depth-dependent

    12. Depth Profile of Uncompensated Spins in an Exchange-Bias System

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

      Depth Profile of Uncompensated Spins in an Exchange-Bias System Print The phenomenon known as exchange bias at the interface between a ferromagnet and an antiferromagnet is currently a subject of intense research because of its applications in the magnetic recording and read-head industries. An international collaboration headed by researchers from the University of California, San Diego, has used resonant x-ray scattering and polarized-neutron reflectometry to determine the depth-dependent

    13. Depth Profile of Uncompensated Spins in an Exchange-Bias System

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

      Depth Profile of Uncompensated Spins in an Exchange-Bias System Depth Profile of Uncompensated Spins in an Exchange-Bias System Print Wednesday, 25 January 2006 00:00 The phenomenon known as exchange bias at the interface between a ferromagnet and an antiferromagnet is currently a subject of intense research because of its applications in the magnetic recording and read-head industries. An international collaboration headed by researchers from the University of California, San Diego, has used

    14. Analysis of Langley optical depth data, with aerosol and gas retrievals,

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

      for the RSS 103 instrument in Barrow, Alaska Analysis of Langley optical depth data, with aerosol and gas retrievals, for the RSS 103 instrument in Barrow, Alaska Gianelli, Scott Columbia University - NASA/GISS Lacis, Andrew NASA/Goddard Institute for Space Studies Carlson, Barbara NASA/Goddard Institute for Space Studies Category: Aerosols Bimodal aerosol retrievals, and high-resolution retrevals of nitrogen dioxide, are performed on the Langley optical depth data from the RSS 103 device

    15. Comparison of Cloud Top Height and Optical Depth Histograms from ISCCP,

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

      MISR, and MODIS Comparison of Cloud Top Height and Optical Depth Histograms from ISCCP, MISR, and MODIS Marchand, Roger Pacific Northwest National Laboratory Ackerman, Thomas Pacific Northwest National Laboratory Category: Cloud Properties Joint histograms of Cloud Top Height (CTH) and Optical Depth (OD) derived by the International Satellite Cloud Climatology Project (ISCCP) are being widely used by the climate modeling community in evaluating global climate models. Similar joint histograms

    16. Non-destructive in-situ method and apparatus for determining radionuclide depth in media

      DOE Patents [OSTI]

      Xu, X. George; Naessens, Edward P.

      2003-01-01

      A non-destructive method and apparatus which is based on in-situ gamma spectroscopy is used to determine the depth of radiological contamination in media such as concrete. An algorithm, Gamma Penetration Depth Unfolding Algorithm (GPDUA), uses point kernel techniques to predict the depth of contamination based on the results of uncollided peak information from the in-situ gamma spectroscopy. The invention is better, faster, safer, and/cheaper than the current practice in decontamination and decommissioning of facilities that are slow, rough and unsafe. The invention uses a priori knowledge of the contaminant source distribution. The applicable radiological contaminants of interest are any isotopes that emit two or more gamma rays per disintegration or isotopes that emit a single gamma ray but have gamma-emitting progeny in secular equilibrium with its parent (e.g., .sup.60 Co, .sup.235 U, and .sup.137 Cs to name a few). The predicted depths from the GPDUA algorithm using Monte Carlo N-Particle Transport Code (MCNP) simulations and laboratory experiments using .sup.60 Co have consistently produced predicted depths within 20% of the actual or known depth.

    17. Measurement of sound speed vs. depth in South Pole ice: pressure waves and shear waves

      SciTech Connect (OSTI)

      IceCube Collaboration; Klein, Spencer

      2009-06-04

      We have measured the speed of both pressure waves and shear waves as a function of depth between 80 and 500 m depth in South Pole ice with better than 1% precision. The measurements were made using the South Pole Acoustic Test Setup (SPATS), an array of transmitters and sensors deployed in the ice at the South Pole in order to measure the acoustic properties relevant to acoustic detection of astrophysical neutrinos. The transmitters and sensors use piezoceramics operating at {approx}5-25 kHz. Between 200 m and 500 m depth, the measured profile is consistent with zero variation of the sound speed with depth, resulting in zero refraction, for both pressure and shear waves. We also performed a complementary study featuring an explosive signal propagating vertically from 50 to 2250 m depth, from which we determined a value for the pressure wave speed consistent with that determined for shallower depths, higher frequencies, and horizontal propagation with the SPATS sensors. The sound speed profile presented here can be used to achieve good acoustic source position and emission time reconstruction in general, and neutrino direction and energy reconstruction in particular. The reconstructed quantities could also help separate neutrino signals from background.

    18. Transition Metal Phosphide Hydroprocessing Catalysts: A review

      SciTech Connect (OSTI)

      Oyama, S.; Gott, T; Zhao, H; Lee, Y

      2009-01-01

      The diminishing quality of oil feedstocks coupled with increasingly more stringent environmental regulations limiting the content of sulfur in transportation fuels have given rise to a need for improved hydroprocessing technology. This review begins with a summary of the major improvements in hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) catalysts and processes that have been reported in recent years. It then describes a new class of hydroprocessing catalysts, the transition metal phosphides, which have emerged as a promising group of high-activity, stable catalysts. The phosphides have physical properties resembling ceramics, so are strong and hard, yet retain electronic and magnetic properties similar to metals. Their crystal structures are based on trigonal prisms, yet they do not form layered structures like the sulfides. They display excellent performance in HDS and HDN, with the most active phosphide, Ni{sub 2}P, having activity surpassing that of promoted sulfides on the basis of sites titrated by chemisorption (CO for the phosphides, O{sub 2} for the sulfides). In the HDS of difficult heteroaromatics like 4,6-dimethyldibenzothiophene Ni{sub 2}P operates by the hydrogenation pathway, while in the HDN of substituted nitrogen compounds like 2-methylpiperidine it carries out nucleophilic substitution. The active sites for hydrogenation in Ni{sub 2}P have a square pyramidal geometry, while those for direct hydrodesulfurization have a tetrahedral geometry. Overall, Ni{sub 2}P is a promising catalyst for deep HDS in the presence of nitrogen and aromatic compounds.

    19. Spotlight on Maine: Transition to a Sustainable Level of Incentives...

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

      Spotlight on Maine: Transition to a Sustainable Level of Incentives Spotlight on Maine: Transition to a Sustainable Level of Incentives Spotlight on Maine: Transition to a ...

    20. Subsidy for Energy Employee Transit (SEET) | Department of Energy

      Office of Environmental Management (EM)

      Subsidy for Energy Employee Transit (SEET) Subsidy for Energy Employee Transit (SEET) The Subsidy for Energy Employees' Transit (SEET) program is designed to promote the use of ...

    1. Cape Cod Regional Transit Authority | Open Energy Information

      Open Energy Info (EERE)

      Cod Regional Transit Authority Jump to: navigation, search Name Cape Cod Regional Transit Authority Facility Cape Cod Regional Transit Authority Sector Wind energy Facility Type...

    2. Railway vehicle body structures

      SciTech Connect (OSTI)

      Not Available

      1985-01-01

      The strength and durability of railway vehicle structures is a major topic of engineering research and design. To reflect this importance the Railway Division of the Institution of Mechanical Engineers organised a conference to discuss all matters relating to railway vehicle design. This book presents the papers discussed in that conference. The contents include: Vehicle body design and the UIC's international contribution; LUL prototype 1986 stock - body structure; vehicle structure for the intermediate capacity transmit system vehicles; car body technology of advanced light rapid transit vehicles; concepts, techniques and experience in the idealization of car body structures for finite element analysis; Calcutta metropolitan railway; design for a lightweight diesel multiple unit body; the design of lightweight inter-city coal structures; the BREL international coach body shell structure; new concepts and design techniques versus material standards; structures of BR diesel electric freight locomotives; structural design philosophy for electric locomotives; suspension design for a locomotive with low structural frequencies; freight wagon structures; a finite element study of coal bodyside panels including the effects of joint flexibility; a fresh approach to the problem of car body design strength; energy absorption in automatic couplings and draw gear; passenger vehicle design loads and structural crashworthiness; design of the front part of railway vehicles (in case of frontal impact); the development of a theoretical technique for rail vehicle structural crashworthiness.

    3. A Spitzer search for transits of radial velocity detected super-Earths

      SciTech Connect (OSTI)

      Kammer, J. A.; Knutson, H. A.; Desert, J.-M.; Howard, A. W.; Laughlin, G. P.; Fortney, J. J.; Deming, D.; Todorov, K. O.; Agol, E.; Burrows, A.; Showman, A. P.; Lewis, N. K.

      2014-02-01

      Unlike hot Jupiters or other gas giants, super-Earths are expected to have a wide variety of compositions, ranging from terrestrial bodies like our own to more gaseous planets like Neptune. Observations of transiting systems, which allow us to directly measure planet masses and radii and constrain atmospheric properties, are key to understanding the compositional diversity of the planets in this mass range. Although Kepler has discovered hundreds of transiting super-Earth candidates over the past 4 yr, the majority of these planets orbit stars that are too far away and too faint to allow for detailed atmospheric characterization and reliable mass estimates. Ground-based transit surveys focus on much brighter stars, but most lack the sensitivity to detect planets in this size range. One way to get around the difficulty of finding these smaller planets in transit is to start by choosing targets that are already known to host super-Earth sized bodies detected using the radial velocity (RV) technique. Here we present results from a Spitzer program to observe six of the most favorable RV-detected super-Earth systems, including HD 1461, HD 7924, HD 156668, HIP 57274, and GJ 876. We find no evidence for transits in any of their 4.5 ?m flux light curves, and place limits on the allowed transit depths and corresponding planet radii that rule out even the most dense and iron-rich compositions for these objects. We also observed HD 97658, but the observation window was based on a possible ground-based transit detection that was later ruled out; thus the window did not include the predicted time for the transit detection recently made by the Microvariability and Oscillations of Stars space telescope.

    4. Metal to semiconductor transition in metallic transition metal dichalcogenides

      SciTech Connect (OSTI)

      Li, Yan; Kang, Jun; Li, Jingbo; Tongay, Sefaattin; Wu, Junqiao; Yue, Qu

      2013-11-07

      We report on tuning the electronic and magnetic properties of metallic transition metal dichalcogenides (mTMDCs) by 2D to 1D size confinement. The stability of the mTMDC monolayers and nanoribbons is demonstrated by the larger binding energy compared to the experimentally available semiconducting TMDCs. The 2D MX{sub 2} (M?=?Nb, Ta; X?=?S, Se) monolayers are non-ferromagnetic metals and mechanically softer compared to their semiconducting TMDCs counterparts. Interestingly, mTMDCs undergo metal-to-semiconductor transition when the ribbon width approaches to ?13? and ?7? for zigzag and armchair edge terminations, respectively; then these ribbons convert back to metal when the ribbon widths further decrease. Zigzag terminated nanoribbons are ferromagnetic semiconductors, and their magnetic properties can also be tuned by hydrogen edge passivation, whereas the armchair nanoribbons are non-ferromagnetic semiconductors. Our results display that the mTMDCs offer a broad range of physical properties spanning from metallic to semiconducting and non-ferromagnetic to ferromagnetic that is ideal for applications where stable narrow bandgap semiconductors with different magnetic properties are desired.

    5. Shim for sealing transition pieces

      DOE Patents [OSTI]

      Lacy, Benjamin Paul; Demiroglu, Mehmet; Sarawate, Neelesh Nandkumar

      2012-07-24

      According to one aspect of the invention, a shim for sealing two adjacent turbine transition pieces is disclosed. The shim includes a circumferential member that includes a first lateral flange and a second lateral flange. Further, the first and second lateral flanges each comprise a tab configured to mate to a first surface plane and the first and second lateral flanges are configured to mate to a second surface plane, wherein the first and second surface planes are substantially parallel. In addition, the shim includes a first flange extending substantially perpendicular from the circumferential member.

    6. SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation

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

      Report and Appendices | Department of Energy and Appendices SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation Report and Appendices This report describes operations at SunLine Transit Agency for a protoype fuel cell bus, a prototype hydrogen hybrid interal combustion engine bus, and five new compressed natural gas buses. 43741-1.pdf (763.42 KB) More Documents & Publications SunLine Transit Agency, Hydrogen-Powered Transit Buses: Preliminary Evaluation Results

    7. Cross-plane thermal properties of transition metal dichalcogenides

      SciTech Connect (OSTI)

      Muratore, C.; Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 ; Varshney, V.; Universal Technology Corporation, Dayton, Ohio 45432 ; Gengler, J. J.; Spectral Energies LLC, Dayton, Ohio 45431 ; Hu, J. J.; Bultman, J. E.; University of Dayton Research Institute, Dayton, Ohio 45469 ; Smith, T. M.; Shamberger, P. J.; Roy, A. K.; Voevodin, A. A.; Qiu, B.; Ruan, X.

      2013-02-25

      In this work, we explore the thermal properties of hexagonal transition metal dichalcogenide compounds with different average atomic masses but equivalent microstructures. Thermal conductivity values of sputtered thin films were compared to bulk crystals. The comparison revealed a >10 fold reduction in thin film thermal conductivity. Structural analysis of the films revealed a turbostratic structure with domain sizes on the order of 5-10 nm. Estimates of phonon scattering lengths at domain boundaries based on computationally derived group velocities were consistent with the observed film microstructure, and accounted for the reduction in thermal conductivity compared to values for bulk crystals.

    8. SU-E-I-11: Cascaded Linear System Model for Columnar CsI Flat Panel Imagers with Depth Dependent Gain and Blur

      SciTech Connect (OSTI)

      Peng, B; Lubinsky, A; Zheng, H; Zhao, W; Teymurazyan, A

      2014-06-01

      Purpose: To implement a depth dependent gain and blur cascaded linear system model (CLSM) for optimizing columnar structured CsI indirect conversion flat panel imager (FPI) for advanced imaging applications. Methods: For experimental validation, depth dependent escape efficiency, e(z), was extracted from PHS measurement of different CsI scintillators (thickness, substrate and light output). The inherent MTF and DQE of CsI was measured using high resolution CMOS sensor. For CLSM, e(z) and the depth dependent MTF(f,z), were estimated using Monte Carlo simulation (Geant4) of optical photon transport through columnar CsI. Previous work showed that Monte Carlo simulation for CsI was hindered by the non-ideality of its columnar structure. In the present work we allowed variation in columnar width with depth, and assumed diffusive reflective backing and columns. Monte Carlo simulation was performed using an optical point source placed at different depth of the CsI layer, from which MTF(z,f) and e(z) were computed. The resulting e(z) with excellent matching with experimental measurements were then applied to the CLSM, Monte Carlo simulation was repeated until the modeled MTF, DQE(f) also match experimental measurement. Results: For a 150 micron FOS HL type CsI, e(z) varies between 0.56 to 0.45, and the MTF at 14 cycles/mm varies between 62.1% to 3.9%, from the front to the back of the scintillator. The overall MTF and DQE(f) at all frequencies are in excellent agreement with experimental measurements at all frequencies. Conclusion: We have developed a CLSM for columnar CsI scintillators with depth dependent gain and MTF, which were estimated from Monte Carlo simulation with novel optical simulation settings. Preliminary results showed excellent agreement between simulation results and experimental measurements. Future work is aimed at extending this approach to optimize CsI screen optic design and sensor structure for achieving higher DQE(f) in cone-beam CT, which uses

    9. ARM: 10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

      DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

      Chitra Sivaraman; Connor Flynn

      1998-03-01

      10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

    10. ARM: 10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

      DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

      Chitra Sivaraman; Connor Flynn

      10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

    11. Theoretical uncertainties in the nuclear matrix elements of neutrinoless double beta decay: The transition operator

      SciTech Connect (OSTI)

      Menndez, Javier

      2013-12-30

      We explore the theoretical uncertainties related to the transition operator of neutrinoless double-beta (0???) decay. The transition operator used in standard calculations is a product of one-body currents, that can be obtained phenomenologically as in Tomoda [1] or imkovic et al. [2]. However, corrections to the operator are hard to obtain in the phenomenological approach. Instead, we calculate the 0??? decay operator in the framework of chiral effective theory (EFT), which gives a systematic order-by-order expansion of the transition currents. At leading orders in chiral EFT we reproduce the standard one-body currents of Refs. [1] and [2]. Corrections appear as two-body (2b) currents predicted by chiral EFT. We compute the effects of the leading 2b currents to the nuclear matrix elements of 0??? decay for several transition candidates. The 2b current contributions are related to the quenching of Gamow-Teller transitions found in nuclear structure calculations.

    12. Depth-resolved ultra-violet spectroscopic photo current-voltage measurements for the analysis of AlGaN/GaN high electron mobility transistor epilayer deposited on Si

      SciTech Connect (OSTI)

      Ozden, Burcu; Yang, Chungman; Tong, Fei; Khanal, Min P.; Mirkhani, Vahid; Sk, Mobbassar Hassan; Ahyi, Ayayi Claude; Park, Minseo

      2014-10-27

      We have demonstrated that the depth-dependent defect distribution of the deep level traps in the AlGaN/GaN high electron mobility transistor (HEMT) epi-structures can be analyzed by using the depth-resolved ultra-violet (UV) spectroscopic photo current-voltage (IV) (DR-UV-SPIV). It is of great importance to analyze deep level defects in the AlGaN/GaN HEMT structure, since it is recognized that deep level defects are the main source for causing current collapse phenomena leading to reduced device reliability. The AlGaN/GaN HEMT epi-layers were grown on a 6 in. Si wafer by metal-organic chemical vapor deposition. The DR-UV-SPIV measurement was performed using a monochromatized UV light illumination from a Xe lamp. The key strength of the DR-UV-SPIV is its ability to provide information on the depth-dependent electrically active defect distribution along the epi-layer growth direction. The DR-UV-SPIV data showed variations in the depth-dependent defect distribution across the wafer. As a result, rapid feedback on the depth-dependent electrical homogeneity of the electrically active defect distribution in the AlGaN/GaN HEMT epi-structure grown on a Si wafer with minimal sample preparation can be elucidated from the DR-UV-SPIV in combination with our previously demonstrated spectroscopic photo-IV measurement with the sub-bandgap excitation.

    13. Giant atomic displacement at a magnetic phase transition in metastable Mn3O4

      SciTech Connect (OSTI)

      Hirai, Shigeto; Moreira Dos Santos, Antonio F; Shapiro, Max C; Molaison, Jamie J; Pradhan, Neelam; Guthrie, Malcolm; Tulk, Christopher A; Fisher, Ian R; Mao, Wendy

      2013-01-01

      We present x-ray, neutron scattering, and heat capacity data that reveal a coupled first-order magnetic and structural phase transition of the metastable mixed-valence postspinel compound Mn3O4 at 210 K. Powder neutron diffraction measurements reveal a magnetic structure in which Mn3+ spins align antiferromagnetically along the edge-sharing a axis, with a magnetic propagation vector k = [1/2,0,0]. In contrast, the Mn2+ spins, which are geometrically frustrated, do not order until a much lower temperature. Although the Mn2+ spins do not directly participate in the magnetic phase transition at 210 K, structural refinements reveal a large atomic shift at this phase transition, corresponding to a physical motion of approximately 0.25 angstrom, even though the crystal symmetry remains unchanged. This "giant" response is due to the coupled effect of built-in strain in the metastable postspinel structure with the orbital realignment of the Mn3+ ion.

    14. Depth profiling analysis of solar wind helium collected in diamond-like carbon film from Genesis

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

      Bajo, Ken-ichi; Olinger, Chad T.; Jurewicz, Amy J.G.; Burnett, Donald S.; Sakaguchi, Isao; Suzuki, Taku; Itose, Satoru; Ishihara, Morio; Uchino, Kiichiro; Wieler, Rainer; et al

      2015-10-01

      The distribution of solar-wind ions in Genesis mission collectors, as determined by depth profiling analysis, constrains the physics of ion solid interactions involving the solar wind. Thus, they provide an experimental basis for revealing ancient solar activities represented by solar-wind implants in natural samples. We measured the first depth profile of ⁴He in a collector; the shallow implantation (peaking at <20 nm) required us to use sputtered neutral mass spectrometry with post-photoionization by a strong field. The solar wind He fluence calculated using depth profiling is ~8.5 x 10¹⁴ cm⁻². The shape of the solar wind ⁴He depth profile ismore » consistent with TRIM simulations using the observed ⁴He velocity distribution during the Genesis mission. It is therefore likely that all solar-wind elements heavier than H are completely intact in this Genesis collector and, consequently, the solar particle energy distributions for each element can be calculated from their depth profiles. Ancient solar activities and space weathering of solar system objects could be quantitatively reproduced by solar particle implantation profiles.« less

    15. Daily snow depth measurements from 195 stations in the United States

      SciTech Connect (OSTI)

      Allison, L.J.; Easterling, D.R.; Jamason, P.; Bowman, D.P.; Hughes, P.Y.; Mason, E.H.

      1997-02-01

      This document describes a database containing daily measurements of snow depth at 195 National Weather Service (NWS) first-order climatological stations in the United States. The data have been assembled and made available by the National Climatic Data Center (NCDC) in Asheville, North Carolina. The 195 stations encompass 388 unique sampling locations in 48 of the 50 states; no observations from Delaware or Hawaii are included in the database. Station selection criteria emphasized the quality and length of station records while seeking to provide a network with good geographic coverage. Snow depth at the 388 locations was measured once per day on ground open to the sky. The daily snow depth is the total depth of the snow on the ground at measurement time. The time period covered by the database is 1893--1992; however, not all station records encompass the complete period. While a station record ideally should contain daily data for at least the seven winter months (January through April and October through December), not all stations have complete records. Each logical record in the snow depth database contains one station`s daily data values for a period of one month, including data source, measurement, and quality flags.

    16. Extraction of depth-dependent perturbation factors for silicon diodes using a plastic scintillation detector

      SciTech Connect (OSTI)

      Lacroix, Frederic; Guillot, Mathieu; McEwen, Malcolm; Gingras, Luc; Beaulieu, Luc

      2011-10-15

      Purpose: This work presents the experimental extraction of the perturbation factor in megavoltage electron beams for three models of silicon diodes (IBA Dosimetry, EFD and SFD, and the PTW 60012 unshielded) using a plastic scintillation detector (PSD). Methods: The authors used a single scanning PSD mounted on a high-precision scanning tank to measure depth-dose curves in 6-, 12-, and 18-MeV clinical electron beams. They also measured depth-dose curves using the IBA Dosimetry, EFD and SFD, and the PTW 60012 unshielded diodes. The authors used the depth-dose curves measured with the PSD as a perturbation-free reference to extract the perturbation factors of the diodes. Results: The authors found that the perturbation factors for the diodes increased substantially with depth, especially for low-energy electron beams. The experimental results show the same trend as published Monte Carlo simulation results for the EFD diode; however, the perturbations measured experimentally were greater. They found that using an effective point of measurement (EPOM) placed slightly away from the source reduced the variation of perturbation factors with depth and that the optimal EPOM appears to be energy dependent. Conclusions: The manufacturer recommended EPOM appears to be incorrect at low electron energy (6 MeV). In addition, the perturbation factors for diodes may be greater than predicted by Monte Carlo simulations.

    17. Terms and Conditions for Site Transition | Department of Energy

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

      Terms and Conditions for Site Transition Terms and Conditions for Site Transition Terms and Conditions for Site Transition Terms and Conditions for Site Transition (207.92 KB) More Documents & Publications Development of Site Transition Plan, Use of the Site Transition Framework, and Terms and Conditions for Site Transition Terms and Conditions for EM Clean Up to the Office of Science Site Transition Framework for Long-Term Surveillance and Maintenance

    18. Structural rejuvenation in bulk metallic glasses

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

      Tong, Yang; Iwashita, T.; Dmowski, Wojciech; Bei, Hongbin; Yokoyama, Y.; Egami, Takeshi

      2015-01-05

      Using high-energy X-ray diffraction we study structural changes in bulk metallic glasses after uniaxial compressive homogeneous deformation at temperatures slightly below the glass transition. We observe that deformation results in structural disordering corresponding to an increase in the fictive, or effective, temperature. However, the structural disordering saturates after yielding. Lastly, examination of the experimental structure and molecular dynamics simulation suggests that local changes in the atomic connectivity network are the main driving force of the structural rejuvenation.

    19. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Third Evaluation Report and Appendices

      SciTech Connect (OSTI)

      Chandler, K.; Eudy, L.

      2008-07-01

      This report describes operations at Alameda-Contra Costa Transit district for three protoype fuel cell buses and six diesel buses operating from the same location.

    20. ToF-SIMS Depth Profiling Of Insulating Samples, Interlaced Mode Or Non-interlaced Mode?

      SciTech Connect (OSTI)

      Wang, Zhaoying; Jin, Ke; Zhang, Yanwen; Wang, Fuyi; Zhu, Zihua

      2014-11-01

      Dual beam depth profiling strategy has been widely adopted in ToF-SIMS depth profiling, in which two basic operation modes, interlaced mode and non-interlaced mode, are commonly used. Generally, interlaced mode is recommended for conductive or semi-conductive samples, whereas non-interlaced mode is recommended for insulating samples, where charge compensation can be an issue. Recent publications, however, show that the interlaced mode can be used effectively for glass depth profiling, despite the fact that glass is an insulator. In this study, we provide a simple guide for choosing between interlaced mode and non-interlaced mode for insulator depth profiling. Two representative cases are presented: (1) depth profiling of a leached glass sample, and (2) depth profiling of a single crystal MgO sample. In brief, the interlaced mode should be attempted first, because (1) it may provide reasonable-quality data, and (2) it is time-saving for most cases, and (3) it introduces low H/C/O background. If data quality is the top priority and measurement time is flexible, non-interlaced mode is recommended because interlaced mode may suffer from low signal intensity and poor mass resolution. A big challenge is tracking trace H/C/O in a highly insulating sample (e.g., MgO), because non-interlaced mode may introduce strong H/C/O background but interlaced mode may suffer from low signal intensity. Meanwhile, a C or Au coating is found to be very effective to improve the signal intensity. Surprisingly, the best analyzing location is not on the C or Au coating, but at the edge (outside) of the coating.

    1. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

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

      Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

    2. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

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

      Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

    3. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

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

      Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

    4. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

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

      Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

    5. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

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

      Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

    6. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

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

      Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

    7. Properties of molecular beam epitaxy grown Eu{sub x}(transition metal){sub y} films (transition metals: Mn, Cr)

      SciTech Connect (OSTI)

      Balin, K.; Nowak, A.; Gibaud, A.; Szade, J.; Celinski, Z.

      2011-04-01

      The electronic and crystallographic structures, as well as the magnetic properties, of Eu{sub x}(transition metal){sub y} (transition metals: Mn, Cr) thin films grown by molecular beam epitaxy were studied. Relative changes of the Eu/Mn and Eu/Cr ratios derived from the XPS lines, as well as x-ray reflectivity, indicate mixing of the Eu/Mn and Eu/Cr layers. Valency transitions from Eu{sup 2+} to Eu{sup 3+} were observed in both systems for most studied stoichiometries. A transition to a magnetically ordered phase was observed at 15 K, 40 K, and 62 K for selected films in the Eu-Mn system, and at 50 K for the film with a Eu/Cr ratio of 0.5.

    8. Performance Assessment for Pump-and-Treat Closure or Transition

      SciTech Connect (OSTI)

      Truex, Michael J.; Johnson, Christian D.; Becker, Dave J.; Lee, Michelle H.; Nimmons, Michael J.

      2015-09-29

      A structured performance assessment approach is useful to evaluate pump-and-treat (P&T) groundwater remediation, which has been applied at numerous sites. Consistent with the U.S. Environmental Protection Agency’s Groundwater Road Map, performance assessment during remedy implementation may be needed, and should consider remedy optimization, transition to alternative remedies, or remedy closure. In addition, a recent National Research Council study examined groundwater remediation at complex contaminated sites and concluded that it may be beneficial to evaluate remedy performance and the potential need for transition to alternative approaches at these sites. The intent of this document is to provide a structured approach for assessing P&T performance to support a decision to optimize, transition, or close a P&T remedy. The process presented in this document for gathering information and performing evaluations to support P&T remedy decisions includes use of decision elements to distinguish between potential outcomes of a remedy decision. Case studies are used to augment descriptions of decision elements and to illustrate each type of outcome identified in the performance assessment approach. The document provides references to resources for tools and other guidance relevant to conducting the P&T assessment.

    9. Soil temperature, soil moisture and thaw depth, Barrow, Alaska, Ver. 1

      DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

      Sloan, V.L.; J.A. Liebig; M.S. Hahn; J.B. Curtis; J.D. Brooks; A. Rogers; C.M. Iversen; R.J. Norby

      This dataset consists of field measurements of soil properties made during 2012 and 2013 in areas A-D of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska. Included are i) weekly measurements of thaw depth, soil moisture, presence and depth of standing water, and soil temperature made during the 2012 and 2013 growing seasons (June - September) and ii) half-hourly measurements of soil temperature logged continuously during the period June 2012 to September 2013.

    10. Soil temperature, soil moisture and thaw depth, Barrow, Alaska, Ver. 1

      DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

      Sloan, V.L.; J.A. Liebig; M.S. Hahn; J.B. Curtis; J.D. Brooks; A. Rogers; C.M. Iversen; R.J. Norby

      2014-01-10

      This dataset consists of field measurements of soil properties made during 2012 and 2013 in areas A-D of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska. Included are i) weekly measurements of thaw depth, soil moisture, presence and depth of standing water, and soil temperature made during the 2012 and 2013 growing seasons (June - September) and ii) half-hourly measurements of soil temperature logged continuously during the period June 2012 to September 2013.

    11. Theoretical studies of atomic transitions

      SciTech Connect (OSTI)

      Fischer, C.F.

      1990-10-01

      This paper discusses: lifetime of excited states; core-polarization studies; large relativistic calculations; Monte Carlo Hartree-Fock (MCHF) atomic structure package; and MCHF codes for the hypercube. (LSP)

    12. DETECTION OF POTENTIAL TRANSIT SIGNALS IN THE FIRST 12 QUARTERS OF KEPLER MISSION DATA

      SciTech Connect (OSTI)

      Tenenbaum, Peter; Jenkins, Jon M.; Seader, Shawn; Burke, Christopher J.; Christiansen, Jessie L.; Rowe, Jason F.; Caldwell, Douglas A.; Clarke, Bruce D.; Li, Jie; Quintana, Elisa V.; Smith, Jeffrey C.; Thompson, Susan E.; Twicken, Joseph D.; Girouard, Forrest R. [Orbital Sciences Corporation and others

      2013-05-01

      We present the results of a search for potential transit signals in the first three years of photometry data acquired by the Kepler mission. The targets of the search include 112,321 targets that were observed over the full interval and an additional 79,992 targets that were observed for a subset of the full interval. From this set of targets we find a total of 11,087 targets that contain at least one signal that meets the Kepler detection criteria: periodicity of the signal, an acceptable signal-to-noise ratio, and three tests that reject false positives. Each target containing at least one detected signal is then searched repeatedly for additional signals, which represent multi-planet systems of transiting planets. When targets with multiple detections are considered, a total of 18,406 potential transiting planet signals are found in the Kepler mission data set. The detected signals are dominated by events with relatively low signal-to-noise ratios and by events with relatively short periods. The distribution of estimated transit depths appears to peak in the range between 20 and 30 parts per million, with a few detections down to fewer than 10 parts per million. The detections exhibit signal-to-noise ratios from 7.1{sigma}, which is the lower cutoff for detections, to over 10,000{sigma}, and periods ranging from 0.5 days, which is the shortest period searched, to 525 days, which is the upper limit of achievable periods given the length of the data set and the requirement that all detections include at least three transits. The detected signals are compared to a set of known transit events in the Kepler field of view, many of which were identified by alternative methods; the comparison shows that the current search recovery rate for targets with known transit events is 98.3%.

    13. Vehicle Technologies Office: Transitioning the Transportation Sector -

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

      Exploring the Intersection of H2 Fuel Cell and Natural Gas Vehicles | Department of Energy Transitioning the Transportation Sector - Exploring the Intersection of H2 Fuel Cell and Natural Gas Vehicles Vehicle Technologies Office: Transitioning the Transportation Sector - Exploring the Intersection of H2 Fuel Cell and Natural Gas Vehicles This report, titled "Transitioning the Transportation Sector: Exploring the Intersection of Hydrogen Fuel Cell and Natural Gas Vehicles" is based

    14. the-schedule-based-transit-model

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

      The Schedule-Based transit model of the Chicago Metropolitan Area Vadim Sokolov Transportation Research and Analysis Computing Center Argonne National Laboratory List of Authors ================ Vadim Sokolov Transportation Research and Analysis Computing Center Argonne National Laboratory 277 International Drive West Chicago, IL 60185 Abstract ========= Usually public transit systems are modeled using so called frequency based approach. In this case transit route times are defined in terms of

    15. Site Transition Guidance | Department of Energy

      Office of Environmental Management (EM)

      Guidance Site Transition Guidance On June 16, 2004, Michael W. Owen, Director, Office of Legacy Management (LM) and Jessie H. Roberson, Assistant Secretary, Office of Environmental ...

    16. Vehicle Technologies Office: Transitioning the Transportation...

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

      This report, titled "Transitioning the Transportation Sector: Exploring the Intersection of Hydrogen Fuel Cell and Natural Gas Vehicles" is based on a workshop that was held on ...

    17. Aspects of the non-zonal transition

      SciTech Connect (OSTI)

      Pueschel, M. J.; Terry, P. W. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)] [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Hatch, D. R. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)] [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)

      2014-05-15

      The non-zonal transition, a process which can bring about very large heat fluxes in gyrokinetic simulations, occurs once a certain threshold plasma ? is reached. This threshold is parameterized via a simulation database, yielding an expression estimating at what ? a given system may approach the transition. Furthermore, the diffusive outward transport of a heat blob in a temperature profile marginally stable with respect to the non-zonal transition is discussed: the resulting transport timescale combines the underlying turbulent transport timescale and the linear instability growth time, thus demonstrating that the non-zonal transition provides a mechanism for very fast heat dissipation.

    18. Transitioning the Transportation Sector: Exploring the Intersection...

      Office of Environmental Management (EM)

      the Intersection of Hydrogen Fuel Cell and Natural Gas Vehicles Transitioning the Transportation Sector: Exploring the Intersection of Hydrogen Fuel Cell and Natural Gas ...

    19. Electronic Spin Transition in Nanosize Stoichiometric Lithium...

      Office of Scientific and Technical Information (OSTI)

      Title: Electronic Spin Transition in Nanosize Stoichiometric Lithium Cobalt Oxide Authors: ... Language: English Subject: energy storage (including batteries and capacitors), defects, ...

    20. Fuel Cells Technology Transit | Open Energy Information

      Open Energy Info (EERE)

      Fuel Cells Technology Transit Place: Clearwater, Florida Zip: 33767 Sector: Hydro, Hydrogen Product: Involved in the development and research of energy models on Hydrogen Energy...

    1. Transitioning Los Alamos technology into the marketplace

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

      All Issues submit Transitioning Los Alamos technology into the marketplace A personal message from Duncan McBranch, Chief Technology Officer, Los Alamos National...

    2. Deputy Director, Office of Technology Transitions

      Broader source: Energy.gov [DOE]

      The Office of Technology Transitions (OTT) is responsible for developing and overseeing the delivery of the DOE strategic vision and goals for technology commercialization and engagement with the...

    3. NO TRANSIT TIMING VARIATIONS IN WASP-4

      SciTech Connect (OSTI)

      Petrucci, R.; Schwartz, M.; Buccino, A. P.; Mauas, P. J. D.; Jofr, E.; Cneo, V.; Gmez, M.; Martnez, C.

      2013-12-20

      We present six new transits of the system WASP-4. Together with 28 light curves published in the literature, we perform a homogeneous study of its parameters and search for variations in the transits' central times. The final values agree with those previously reported, except for a slightly lower inclination. We find no significant long-term variations in i or R{sub P} /R {sub *}. The O-C mid-transit times do not show signs of transit timing variations greater than 54s.

    4. CHARACTERIZATION OF TRANSITIONS IN THE SOLAR WIND PARAMETERS

      SciTech Connect (OSTI)

      Perri, S.; Balogh, A. E-mail: a.balogh@imperial.ac.u

      2010-02-20

      The distinction between fast and slow solar wind streams and the dynamically evolved interaction regions is reflected in the characteristic fluctuations of both the solar wind and the embedded magnetic field. High-resolution magnetic field data from the Ulysses spacecraft have been analyzed. The observations show rapid variations in the magnetic field components and in the magnetic field strength, suggesting a structured nature of the solar wind at small scales. The typical sizes of fluctuations cover a broad range. If translated to the solar surface, the scales span from the size of granules ({approx}10{sup 3} km) and supergranules ({approx}10{sup 4} km) on the Sun down to {approx}10{sup 2} km and less. The properties of the short time structures change in the different types of solar wind. While fluctuations in fast streams are more homogeneous, slow streams present a bursty behavior in the magnetic field variances, and the regions of transition are characterized by high levels of power in narrow structures around the transitions. The probability density functions of the magnetic field increments at several scales reveal a higher level of intermittency in the mixed streams, which is related to the presence of well localized features. It is concluded that, apart from the differences in the nature of fluctuations in flows of different coronal origin, there is a small-scale structuring that depends on the origin of streams themselves but it is also related to a bursty generation of the fluctuations.

    5. TRANSITION STATE FOR THE GAS-PHASE REACTION OF URANIUM HEXAFLUORIDE WITH WATER

      SciTech Connect (OSTI)

      Garrison, S; James Becnel, J

      2008-03-18

      Density Functional Theory and small-core, relativistic pseudopotentials were used to look for symmetric and asymmetric transitions states of the gas-phase hydrolysis reaction of uranium hexafluoride, UF{sub 6}, with water. At the B3LYP/6-31G(d,p)/SDD level, an asymmetric transition state leading to the formation of a uranium hydroxyl fluoride, U(OH)F{sub 5}, and hydrogen fluoride was found with an energy barrier of +77.3 kJ/mol and an enthalpy of reaction of +63.0 kJ/mol (both including zero-point energy corrections). Addition of diffuse functions to all atoms except uranium led to only minor changes in the structure and relative energies of the reacting complex and transition state. However, a significant change in the product complex structure was found, significantly reducing the enthalpy of reaction to +31.9 kJ/mol. Similar structures and values were found for PBE0 and MP2 calculations with this larger basis set, supporting the B3LYP results. No symmetric transition state leading to the direct formation of uranium oxide tetrafluoride, UOF{sub 4}, was found, indicating that the reaction under ambient conditions likely includes several more steps than the mechanisms commonly mentioned. The transition state presented here appears to be the first published transition state for the important gas-phase reaction of UF{sub 6} with water.

    6. Depinning transition of a domain wall in ferromagnetic films

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

      Xi, Bin; Luo, Meng -Bo; Vinokur, Valerii M.; Hu, Xiao

      2015-09-14

      We report first principle numerical study of domain wall (DW) depinning in two-dimensional magnetic film, which is modeled by 2D random-field Ising system with the dipole-dipole interaction. We observe non-conventional activation-type motion of DW and reveal the fractal structure of DW near the depinning transition. We determine scaling functions describing critical dynamics near the transition and obtain universal exponents establishing connection between thermal softening of pinning potential and critical dynamics. In addition, we observe that tuning the strength of the dipole-dipole interaction switches DW dynamics between two different universality classes, corresponding to two distinct dynamic regimes characterized by non-Arrhenius andmore » conventional Arrhenius-type DW motions.« less

    7. Ductile-to-brittle transition in spallation of metallic glasses

      SciTech Connect (OSTI)

      Huang, X.; Ling, Z.; Dai, L. H.

      2014-10-14

      In this paper, the spallation behavior of a binary metallic glass Cu{sub 50}Zr{sub 50} is investigated with molecular dynamics simulations. With increasing the impact velocity, micro-voids induced by tensile pulses become smaller and more concentrated. The phenomenon suggests a ductile-to-brittle transition during the spallation process. Further investigation indicates that the transition is controlled by the interaction between void nucleation and growth, which can be regarded as a competition between tension transformation zones (TTZs) and shear transformation zones (STZs) at atomic scale. As impact velocities become higher, the stress amplitude and temperature rise in the spall region increase and micro-structures of the material become more unstable. Therefore, TTZs are prone to activation in metallic glasses, leading to a brittle behavior during the spallation process.

    8. Hydrocarbon-free resonance transition 795-nm rubidium laser

      SciTech Connect (OSTI)

      Wu, S Q; Soules, T F; Page, R H; Mitchell, S C; Kanz, V K; Beach, R J

      2008-01-09

      An optical resonance transition rubidium laser (5{sup 2}P{sub 1/2} {yields} 5{sup 2}S{sub 1/2}) is demonstrated with a hydrocarbon-free buffer gas. Prior demonstrations of alkali resonance transition lasers have used ethane as either the buffer gas or a buffer gas component to promote rapid fine-structure mixing. However, our experience suggests that the alkali vapor reacts with the ethane producing carbon as one of the reaction products. This degrades long term laser reliability. Our recent experimental results with a 'clean' helium-only buffer gas system pumped by a Ti:sapphire laser demonstrate all the advantages of the original alkali laser system, but without the reliability issues associated with the use of ethane.

    9. Depinning transition of a domain wall in ferromagnetic films

      SciTech Connect (OSTI)

      Xi, Bin; Luo, Meng -Bo; Vinokur, Valerii M.; Hu, Xiao

      2015-09-14

      We report first principle numerical study of domain wall (DW) depinning in two-dimensional magnetic film, which is modeled by 2D random-field Ising system with the dipole-dipole interaction. We observe non-conventional activation-type motion of DW and reveal the fractal structure of DW near the depinning transition. We determine scaling functions describing critical dynamics near the transition and obtain universal exponents establishing connection between thermal softening of pinning potential and critical dynamics. In addition, we observe that tuning the strength of the dipole-dipole interaction switches DW dynamics between two different universality classes, corresponding to two distinct dynamic regimes characterized by non-Arrhenius and conventional Arrhenius-type DW motions.

    10. Long-Term Stewardship Baseline Report and Transition Guidance

      SciTech Connect (OSTI)

      Kristofferson, Keith

      2001-11-01

      Long-term stewardship consists of those actions necessary to maintain and demonstrate continued protection of human health and the environment after facility cleanup is complete. As the Department of Energys (DOE) lead laboratory for environmental management programs, the Idaho National Engineering and Environmental Laboratory (INEEL) administers DOEs long-term stewardship science and technology efforts. The INEEL provides DOE with technical, and scientific expertise needed to oversee its long-term environmental management obligations complexwide. Long-term stewardship is administered and overseen by the Environmental Management Office of Science and Technology. The INEEL Long-Term Stewardship Program is currently developing the management structures and plans to complete INEEL-specific, long-term stewardship obligations. This guidance document (1) assists in ensuring that the program leads transition planning for the INEEL with respect to facility and site areas and (2) describes the classes and types of criteria and data required to initiate transition for areas and sites where the facility mission has ended and cleanup is complete. Additionally, this document summarizes current information on INEEL facilities, structures, and release sites likely to enter long-term stewardship at the completion of DOEs cleanup mission. This document is not intended to function as a discrete checklist or local procedure to determine readiness to transition. It is an overarching document meant as guidance in implementing specific transition procedures. Several documents formed the foundation upon which this guidance was developed. Principal among these documents was the Long-Term Stewardship Draft Technical Baseline; A Report to Congress on Long-Term Stewardship, Volumes I and II; Infrastructure Long-Range Plan; Comprehensive Facility Land Use Plan; INEEL End-State Plan; and INEEL Institutional Plan.

    11. SunLine Transit Agency Hydrogen-Powered Transit Buses: Evaluation...

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

      SunLine Transit Agency Hydrogen-Powered Transit Buses: Evaluation Results Update This report provides an update on the evaluation results for hydrogen and CNG-fueled buses ...

    12. Structural health monitoring for ship structures

      SciTech Connect (OSTI)

      Farrar, Charles; Park, Gyuhae; Angel, Marian; Bement, Matthew; Salvino, Liming

      2009-01-01

      Currently the Office of Naval Research is supporting the development of structural health monitoring (SHM) technology for U.S. Navy ship structures. This application is particularly challenging because of the physical size of these structures, the widely varying and often extreme operational and environmental conditions associated with these ships missions, lack of data from known damage conditions, limited sensing that was not designed specifically for SHM, and the management of the vast amounts of data that can be collected during a mission. This paper will first define a statistical pattern recognition paradigm for SHM by describing the four steps of (1) Operational Evaluation, (2) Data Acquisition, (3) Feature Extraction, and (4) Statistical Classification of Features as they apply to ship structures. Note that inherent in the last three steps of this process are additional tasks of data cleansing, compression, normalization and fusion. The presentation will discuss ship structure SHM challenges in the context of applying various SHM approaches to sea trials data measured on an aluminum multi-hull high-speed ship, the HSV-2 Swift. To conclude, the paper will discuss several outstanding issues that need to be addressed before SHM can make the transition from a research topic to actual field applications on ship structures and suggest approaches for addressing these issues.

    13. Possibility of using cylindrical ionization chambers for percent depth-dose measurements in clinical electron beams

      SciTech Connect (OSTI)

      Ono, Takeshi; Araki, Fujio; Yoshiyama, Fumiaki

      2011-08-15

      Purpose: This study investigated the possibility of using cylindrical ionization chambers for percent depth-dose (PDD) measurements in high-energy clinical electron beams. Methods: The cavity correction factor, P{sub cav}, for cylindrical chambers with various diameters was calculated as a function of depth from the surface to R{sub 50}, in the energy range of 6-18 MeV electrons with the EGSnrc C ++ -based user-code CAVITY. The results were compared with those for IBA NACP-02 and PTW Roos parallel-plate ionization chambers. The effective point of measurement (EPOM) for the cylindrical chamber and the parallel-plate chamber was positioned according to the IAEA TRS-398 code of practice. The overall correction factor, P{sub Q}, and the percent depth-ionization (PDI) curve for a PTW30013 Farmer-type chamber were also compared with those of NACP-02 and Roos chambers. Results: The P{sub cav} values at depths between the surface and R{sub 50} for cylindrical chambers were all lower than those with parallel-plate chambers. However, the variation in depth for cylindrical chambers equal to or less than 4 mm in diameter was equivalent to or smaller than that for parallel-plate chambers. The P{sub Q} values for the PTW30013 chamber mainly depended on P{sub cav}, and for parallel-plate chambers depended on the wall correction factor, P{sub wall}, rather than P{sub cav}. P{sub Q} at depths from the surface to R{sub 50} for the PTW30013 chamber was consequently a lower value than that with parallel-plate chambers. However, the variation in depth was equivalent to that of parallel-plate chambers at electron energies equal to or greater than 9 MeV. The shift to match calculated PDI curves for the PTW30013 chamber and water (perturbation free) varied from 0.65 to 0 mm between 6 and 18 MeV beams. Similarly, the shifts for NACP-02 and Roos chambers were 0.5-0.6 mm and 0.2-0.3 mm, respectively, and were nearly independent of electron energy. Conclusions: Calculated PDI curves for PTW

    14. Emission Testing of Washington Metropolitan Area Transit Authority (WMATA) Natural Gas and Diesel Transit Buses

      Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

      Emission Testing of Washington Metropolitan Area Transit Authority (WMATA) Natural Gas and Diesel Transit Buses M. Melendez, J. Taylor, and J. Zuboy National Renewable Energy Laboratory W.S. Wayne West Virginia University D. Smith U.S. Department of Energy Technical Report NREL/TP-540-36355 December 2005 Emission Testing of Washington Metropolitan Area Transit Authority (WMATA) Natural Gas and Diesel Transit Buses M. Melendez, J. Taylor, and J. Zuboy National Renewable Energy Laboratory W.S.

    15. New York City Transit Hybrid and CNG Transit Buses: Interim Evaluation Results

      Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

      New York City Transit Hybrid and CNG Transit Buses: Interim Evaluation Results K. Chandler and E. Eberts Battelle L. Eudy National Renewable Energy Laboratory Technical Report NREL/TP-540-38843 January 2006 New York City Transit Hybrid and CNG Transit Buses: Interim Evaluation Results K. Chandler and E. Eberts Battelle L. Eudy National Renewable Energy Laboratory Prepared under Task No. FC06.3000 Technical Report NREL/TP-540-38843 January 2006 National Renewable Energy Laboratory 1617 Cole

    16. Emission Testing of Washington Metropolitan Area Transit Authority (WMATA) Natural Gas and Diesel Transit Buses

      SciTech Connect (OSTI)

      Melendez, M.; Taylor, J.; Wayne, W. S.; Smith, D.; Zuboy, J.

      2005-12-01

      An evaluation of emissions of natural gas and diesel buses operated by the Washington Metro Area Transit Authority.

    17. Insulator to correlated metal transition in V_1-xMo_xO_2

      SciTech Connect (OSTI)

      Klimczuk, Tomasz; Ronning, Filip; Holman, Katherine; Mcqueen, Tyrel M; Williams, Anthony J; Stephens, P W; Zandbergen, Henny W; Xu, Q; Cava, Robert J

      2009-01-01

      The change from metallic to insulating states is one of the most dramatic transitions that solids undergo on cooling or chemical doping. Many materials display this transition, but only a handful have the right combination of crystal structure and physical properties to serve as model systems. VO{sub 2} is one of those materials. Using Mo as a chemical dopant in VO{sub 2}, we find unanticipated phenomenology for both the electronic and structural characteristics of the resulting insulator to metal transition. The results support a complex, previously proposed scenario involving the coexistence of both electron repulsion and electron pairing for yielding an insulator in VO{sub 2}, but not simply; many issues are raised about local versus itinerant behavior and structure-property correlations in this most iconic ofdoped correlated electron systems.

    18. X-ray Emission Spectroscopy in Magnetic 3d-Transition Metals

      SciTech Connect (OSTI)

      Iota, V; Park, J; Baer, B; Yoo, C; Shen, G

      2003-11-18

      The application of high pressure affects the band structure and magnetic interactions in solids by modifying nearest-neighbor distances and interatomic potentials. While all materials experience electronic changes with increasing pressure, spin polarized, strongly electron correlated materials are expected to undergo the most dramatic transformations. In such materials, (d and f-electron metals and compounds), applied pressure reduces the strength of on-site correlations, leading to increased electron delocalization and, eventually, to loss of its magnetism. In this ongoing project, we study the electronic and magnetic properties of Group VIII, 3d (Fe, Co and Ni) magnetic transition metals and their compounds at high pressures. The high-pressure properties of magnetic 3d-transition metals and compounds have been studied extensively over the years, because of iron being a major constituent of the Earth's core and its relevance to the planetary modeling to understand the chemical composition, internal structure, and geomagnetism. However, the fundamental scientific interest in the high-pressure properties of magnetic 3d-electron systems extends well beyond the geophysical applications to include the electron correlation-driven physics. The role of magnetic interactions in the stabilization of the ''non-standard'' ambient pressure structures of Fe, Co and Ni is still incompletely understood. Theoretical studies have predicted (and high pressure experiments are beginning to show) strong correlations between the electronic structure and phase stability in these materials. The phase diagrams of magnetic 3d systems reflect a delicate balance between spin interactions and structural configuration. At ambient conditions, the crystal structures of {alpha}-Fe(bcc) and {var_epsilon}-Co(hcp) phases depart from the standard sequence (hcp {yields} bcc{yields} hcp {yields} fcc), as observed in all other non-magnetic transition metals with increasing the d-band occupancy, and are

    19. Method for dry etching of transition metals

      DOE Patents [OSTI]

      Ashby, C.I.H.; Baca, A.G.; Esherick, P.; Parmeter, J.E.; Rieger, D.J.; Shul, R.J.

      1998-09-29

      A method for dry etching of transition metals is disclosed. The method for dry etching of a transition metal (or a transition metal alloy such as a silicide) on a substrate comprises providing at least one nitrogen- or phosphorus-containing {pi}-acceptor ligand in proximity to the transition metal, and etching the transition metal to form a volatile transition metal/{pi}-acceptor ligand complex. The dry etching may be performed in a plasma etching system such as a reactive ion etching (RIE) system, a downstream plasma etching system (i.e. a plasma afterglow), a chemically-assisted ion beam etching (CAIBE) system or the like. The dry etching may also be performed by generating the {pi}-acceptor ligands directly from a ligand source gas (e.g. nitrosyl ligands generated from nitric oxide), or from contact with energized particles such as photons, electrons, ions, atoms, or molecules. In some preferred embodiments of the present invention, an intermediary reactant species such as carbonyl or a halide ligand is used for an initial chemical reaction with the transition metal, with the intermediary reactant species being replaced at least in part by the {pi}-acceptor ligand for forming the volatile transition metal/{pi}-acceptor ligand complex.

    20. Method for dry etching of transition metals

      DOE Patents [OSTI]

      Ashby, Carol I. H.; Baca, Albert G.; Esherick, Peter; Parmeter, John E.; Rieger, Dennis J.; Shul, Randy J.

      1998-01-01

      A method for dry etching of transition metals. The method for dry etching of a transition metal (or a transition metal alloy such as a silicide) on a substrate comprises providing at least one nitrogen- or phosphorous-containing .pi.-acceptor ligand in proximity to the transition metal, and etching the transition metal to form a volatile transition metal/.pi.-acceptor ligand complex. The dry etching may be performed in a plasma etching system such as a reactive ion etching (RIE) system, a downstream plasma etching system (i.e. a plasma afterglow), a chemically-assisted ion beam etching (CAIBE) system or the like. The dry etching may also be performed by generating the .pi.-acceptor ligands directly from a ligand source gas (e.g. nitrosyl ligands generated from nitric oxide), or from contact with energized particles such as photons, electrons, ions, atoms, or molecules. In some preferred embodiments of the present invention, an intermediary reactant species such as carbonyl or a halide ligand is used for an initial chemical reaction with the transition metal, with the intermediary reactant species being replaced at least in part by the .pi.-acceptor ligand for forming the volatile transition metal/.pi.-acceptor ligand complex.

    1. Energy Transition Initiative: Islands Playbook (Book)

      SciTech Connect (OSTI)

      Not Available

      2015-01-01

      The Island Energy Playbook (the Playbook) provides an action-oriented guide to successfully initiating, planning, and completing a transition to an energy system that primarily relies on local resources to eliminate a dependence on one or two imported fuels. It is intended to serve as a readily available framework that any community can adapt to organize its own energy transition effort.

    2. Superconducting transition temperature in anodized aluminum

      SciTech Connect (OSTI)

      Leemann, C.; Elliott, J.H.; Deutscher, G.; Orbach, R.; Wolf, S.A.

      1983-08-01

      We have measured the superconducting transition temperature of anodized aluminum films of grain sizes ranging from less than 100 to 3000 A. The transition temperature is 1.8 K for films of grain size 100 A and decreases monotonically with increasing grain size to 1.2 K for 3000-A grains. The effect depends only on the volume of the grains.

    3. QCD Phase Transitions, Volume 15

      SciTech Connect (OSTI)

      Schaefer, T.; Shuryak, E.

      1999-03-20

      The title of the workshop, ''The QCD Phase Transitions'', in fact happened to be too narrow for its real contents. It would be more accurate to say that it was devoted to different phases of QCD and QCD-related gauge theories, with strong emphasis on discussion of the underlying non-perturbative mechanisms which manifest themselves as all those phases. Before we go to specifics, let us emphasize one important aspect of the present status of non-perturbative Quantum Field Theory in general. It remains true that its studies do not get attention proportional to the intellectual challenge they deserve, and that the theorists working on it remain very fragmented. The efforts to create Theory of Everything including Quantum Gravity have attracted the lion share of attention and young talent. Nevertheless, in the last few years there was also a tremendous progress and even some shift of attention toward emphasis on the unity of non-perturbative phenomena. For example, we have seen some efforts to connect the lessons from recent progress in Supersymmetric theories with that in QCD, as derived from phenomenology and lattice. Another example is Maldacena conjecture and related development, which connect three things together, string theory, super-gravity and the (N=4) supersymmetric gauge theory. Although the progress mentioned is remarkable by itself, if we would listen to each other more we may have chance to strengthen the field and reach better understanding of the spectacular non-perturbative physics.

    4. Distinguishing Unfolding and Functional Conformational Transitions of Calmodulin Using Ultraviolet Resonance Raman Spectroscopy

      SciTech Connect (OSTI)

      Jones, Eric M.; Balakrishnan, G.; Squier, Thomas C.; Spiro, Thomas

      2014-06-14

      Calmodulin (CaM) is a ubiquitous moderator protein for calcium signaling in all eukaryotic cells. This small calcium-binding protein exhibits a broad range of structural transitions, including domain opening and folding-unfolding, that allow it to recognize a wide variety of binding partners in vivo. While the static structures of CaM associated with its various binding activities are fairly well known, it has been challenging to examine the dynamics of transition between these structures in real-time, due to a lack of suitable spectroscopic probes of CaM structure. In this paper, we examine the potential of ultraviolet resonance Raman (UVRR) spectroscopy for clarifying the nature of structural transitions in CaM. We find that the UVRR spectral change (with 229 nm excitation) due to thermal unfolding of CaM is qualitatively different from that associated with opening of the C-terminal domain in response to Ca2+ binding. This spectral difference is entirely due to differences in teritary contacts at the inter-domain tyrosine residue Tyr138, toward which other spectroscopic methods are not sensitive. We conclude that UVRR is ideally suited to identifying the different types of structural transitions in CaM and other proteins with conformation-sensitive tyrosine residues, opening a path to time-resolved studies of CaM dynamics using Raman spectroscopy.

    5. Stainless Steel to Titanium Bimetallic Transitions

      SciTech Connect (OSTI)

      Kaluzny, J. A.; Grimm, C.; Passarelli, D.

      2015-01-01

      In order to use stainless steel piping in an LCLS-II (Linac Coherent Light Source Upgrade) cryomodule, stainless steel to titanium bimetallic transitions are needed to connect the stainless steel piping to the titanium cavity helium vessel. Explosion bonded stainless steel to titanium transition pieces and bimetallic transition material samples have been tested. A sample transition tube was subjected to tests and x-ray examinations between tests. Samples of the bonded joint material were impact and tensile tested at room temperature as well as liquid helium temperature. The joint has been used successfully in horizontal tests of LCLS-II cavity helium vessels and is planned to be used in LCLS-II cryomodules. Results of material sample and transition tube tests will be presented.

    6. SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation

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

      Report -- Appendices | Department of Energy -- Appendices SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation Report -- Appendices This report describes operations at SunLine Transit Agency for a protoype fuel cell bus, a prototype hydrogen hybrid interal combustion engine bus, and five new compressed natural gas buses. For main report, see NREL/TP-560-43741. 43741-2.pdf (1.69 MB) More Documents & Publications SunLine Transit Agency, Hydrogen-Powered Transit Buses:

    7. Assessing strategies to address transition costs in a restructuring electricity industry

      SciTech Connect (OSTI)

      Baxter, L.; Hadley, S.; Hirst, E.

      1996-08-01

      Restructuring the US electricity industry has become the nation`s central energy issue for the 1990s. Restructuring proposals at the federal and state levels focus on more competitive market structures for generation and the integration of transmission within those structures. The proposed move to more competitive generation markets will expose utility costs that are above those experienced by alternative suppliers. Debate about these above-market, or transition, costs (e.g., their size,who will pay for them and how) has played a prominent role in restructuring proceedings. This paper presents results from a project to systematically assess strategies to address transition costs exposed by restructuring the electricity industry.

    8. Conventional empirical law reverses in the phase transitions of 122-type iron-based superconductors

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

      Yu, Zhenhai; Wang, Lin; Wang, Luhong; Liu, Haozhe; Zhao, Jinggeng; Li, Chunyu; Sinogeikin, Stanislav; Wu, Wei; Luo, Jianlin; Wang, Nanlin; et al

      2014-11-24

      Phase transition of solid-state materials is a fundamental research topic in condensed matter physics, materials science and geophysics. It has been well accepted and widely proven that isostructural compounds containing different cations undergo same pressure-induced phase transitions but at progressively lower pressures as the cation radii increases. However, we discovered that this conventional law reverses in the structural transitions in 122-type iron-based superconductors. In this report, a combined low temperature and high pressure X-ray diffraction (XRD) measurement has identified the phase transition curves among the tetragonal (T), orthorhombic (O) and the collapsed-tetragonal (cT) phases in the structural phase diagram ofmore » the iron-based superconductor AFe2As2 (A = Ca, Sr, Eu, and Ba). As a result, the cation radii dependence of the phase transition pressure (T → cT) shows an opposite trend in which the compounds with larger ambient radii cations have a higher transition pressure.« less

    9. Conventional empirical law reverses in the phase transitions of 122-type iron-based superconductors

      SciTech Connect (OSTI)

      Yu, Zhenhai; Wang, Lin; Wang, Luhong; Liu, Haozhe; Zhao, Jinggeng; Li, Chunyu; Sinogeikin, Stanislav; Wu, Wei; Luo, Jianlin; Wang, Nanlin; Yang, Ke; Zhao, Yusheng; Mao, Ho -kwang

      2014-11-24

      Phase transition of solid-state materials is a fundamental research topic in condensed matter physics, materials science and geophysics. It has been well accepted and widely proven that isostructural compounds containing different cations undergo same pressure-induced phase transitions but at progressively lower pressures as the cation radii increases. However, we discovered that this conventional law reverses in the structural transitions in 122-type iron-based superconductors. In this report, a combined low temperature and high pressure X-ray diffraction (XRD) measurement has identified the phase transition curves among the tetragonal (T), orthorhombic (O) and the collapsed-tetragonal (cT) phases in the structural phase diagram of the iron-based superconductor AFe2As2 (A = Ca, Sr, Eu, and Ba). As a result, the cation radii dependence of the phase transition pressure (T → cT) shows an opposite trend in which the compounds with larger ambient radii cations have a higher transition pressure.

    10. Information and Records Management Transition Guidance | Department of

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

      Energy Information and Records Management Transition Guidance Information and Records Management Transition Guidance Information and Records Management Transition Guidance (March 2004) Information and Records Management Transition Guidance (869.4 KB) More Documents & Publications LM Records and Information Management Transition Guidance (May 2016) ADMINISTRATIVE RECORDS SCHEDULE 20: ELECTRONIC RECORDS ADMINISTRATIVE RECORDS SCHEDULE 20: ELECTRONIC RECORDS

    11. Combined UHV/high-pressure catalysis setup for depth-resolved near-surface spectroscopic characterization and catalytic testing of model catalysts

      SciTech Connect (OSTI)

      Mayr, Lukas; Kltzer, Bernhard; Penner, Simon; Rameshan, Raffael; Department of Inorganic Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin ; Rameshan, Christoph; Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/BC/01, 1060 Vienna

      2014-05-15

      An ultra-high vacuum (UHV) setup for real and inverse model catalyst preparation, depth-resolved near-surface spectroscopic characterization, and quantification of catalytic activity and selectivity under technologically relevant conditions is described. Due to the all-quartz reactor attached directly to the UHV-chamber, transfer of the catalyst for in situ testing without intermediate contact to the ambient is possible. The design of the UHV-compatible re-circulating batch reactor setup allows the study of reaction kinetics under close to technically relevant catalytic conditions up to 1273 K without contact to metallic surfaces except those of the catalyst itself. With the attached differentially pumped exchangeable evaporators and the quartz-microbalance thickness monitoring equipment, a reproducible, versatile, and standardised sample preparation is possible. For three-dimensional near-surface sample characterization, the system is equipped with a hemispherical analyser for X-ray photoelectron spectroscopy (XPS), electron-beam or X-ray-excited Auger-electron spectroscopy, and low-energy ion scattering measurements. Due the dedicated geometry of the X-ray gun (54.7, magic angle) and the rotatable sample holder, depth analysis by angle-resolved XPS measurements can be performed. Thus, by the combination of characterisation methods with different information depths, a detailed three-dimensional picture of the electronic and geometric structure of the model catalyst can be obtained. To demonstrate the capability of the described system, comparative results for depth-resolved sample characterization and catalytic testing in methanol steam reforming on PdGa and PdZn near-surface intermetallic phases are shown.

    12. Pseudopotentials for quantum Monte Carlo studies of transition metal oxides

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

      Krogel, Jaron T.; Santana Palacio, Juan A.; Reboredo, Fernando A.

      2016-02-22

      Quantum Monte Carlo (QMC) calculations of transition metal oxides are partially limited by the availability of high-quality pseudopotentials that are both accurate in QMC and compatible with major plane-wave electronic structure codes. We have generated a set of neon-core pseudopotentials with small cutoff radii for the early transition metal elements Sc to Zn within the local density approximation of density functional theory. The pseudopotentials have been directly tested for accuracy within QMC by calculating the first through fourth ionization potentials of the isolated transition metal (M) atoms and the binding curve of each M-O dimer. We find the ionization potentialsmore » to be accurate to 0.16(1) eV, on average, relative to experiment. The equilibrium bond lengths of the dimers are within 0.5(1)% of experimental values, on average, and the binding energies are also typically accurate to 0.18(3) eV. The level of accuracy we find for atoms and dimers is comparable to what has recently been observed for bulk metals and oxides using the same pseudopotentials. Our QMC pseudopotential results compare well with the findings of previous QMC studies and benchmark quantum chemical calculations.« less

    13. Systems and methods that generate height map models for efficient three dimensional reconstruction from depth information

      DOE Patents [OSTI]

      Frahm, Jan-Michael; Pollefeys, Marc Andre Leon; Gallup, David Robert

      2015-12-08

      Methods of generating a three dimensional representation of an object in a reference plane from a depth map including distances from a reference point to pixels in an image of the object taken from a reference point. Weights are assigned to respective voxels in a three dimensional grid along rays extending from the reference point through the pixels in the image based on the distances in the depth map from the reference point to the respective pixels, and a height map including an array of height values in the reference plane is formed based on the assigned weights. An n-layer height map may be constructed by generating a probabilistic occupancy grid for the voxels and forming an n-dimensional height map comprising an array of layer height values in the reference plane based on the probabilistic occupancy grid.

    14. Effect of Ion Skin Depth on Relaxation of Merging Spheromaks to a Field-Reversed Configuration

      SciTech Connect (OSTI)

      Kawamori, Eiichirou; Ono, Yasushi

      2005-08-19

      The effect of ion skin depth on the relaxation of merging spheromaks to a field-reversed configuration (FRC) is studied experimentally for a wide range of size parameter S* (ratio of minor radius to ion skin depth) from 1 to 7. The two merging spheromaks are observed to relax to an FRC or a new spheromak depending on whether the initial poloidal eigenvalue is smaller or larger than a threshold value. The bifurcation value is found to increase with decreasing size parameter S{sup *}, indicating that the low-S* condition provides a wide bifurcated range of relaxation to an FRC. The FRC-style relaxation under the low-S* conditions was accompanied by the suppression of the low-n modes (n is the toroidal mode number) activity. The fast rotations of the modes were followed by suppression of the low-n modes.

    15. Surface hardening of titanium alloys with melting depth controlled by heat sink

      DOE Patents [OSTI]

      Oden, Laurance L.; Turner, Paul C.

      1995-01-01

      A process for forming a hard surface coating on titanium alloys includes providing a piece of material containing titanium having at least a portion of one surface to be hardened. The piece having a portion of a surface to be hardened is contacted on the backside by a suitable heat sink such that the melting depth of said surface to be hardened may be controlled. A hardening material is then deposited as a slurry. Alternate methods of deposition include flame, arc, or plasma spraying, electrodeposition, vapor deposition, or any other deposition method known by those skilled in the art. The surface to be hardened is then selectively melted to the desired depth, dependent on the desired coating thickness, such that a molten pool is formed of the piece surface and the deposited hardening material. Upon cooling a hardened surface is formed.

    16. Microtopographic and depth controls on active layer chemistry in Arctic polygonal ground

      SciTech Connect (OSTI)

      Newman, Brent D.; Throckmorton, Heather M.; Graham, David E.; Gu, Baohua; Hubbard, Susan S.; Liang, Liyuan; Wu, Yuxin; Heikoop, J. M.; Herndon, Elizabeth M.; Phelps, Tommy J.; Wilson, Cathy; Wullschleger, Stan D.

      2015-03-24

      Polygonal ground is a signature characteristic of Arctic lowlands, and carbon release from permafrost thaw can alter feedbacks to Arctic ecosystems and climate. This study describes the first comprehensive spatial examination of active layer biogeochemistry that extends across high- and low-centered, ice wedge polygons, their features, and with depth. Water chemistry measurements of 54 analytes were made on surface and active layer pore waters collected near Barrow, Alaska, USA. Significant differences were observed between high- and low-centered polygons suggesting that polygon types may be useful for landscape-scale geochemical classification. However, differences were found for polygon features (centers and troughs) for analytes that were not significant for polygon type, suggesting that finer-scale features affect biogeochemistry differently from polygon types. Depth variations were also significant, demonstrating important multidimensional aspects of polygonal ground biogeochemistry. These results have major implications for understanding how polygonal ground ecosystems function, and how they may respond to future change.

    17. Activation of methane by transition metal-substituted aluminophosphate molecular sieves

      DOE Patents [OSTI]

      Iton, Lennox E.; Maroni, Victor A.

      1991-01-01

      Aluminophosphate molecular sieves substituted with cobalt, manganese or iron and having the AlPO.sub.4 -34 or AlPO.sub.4 -5, or related AlPO.sub.4 structure activate methane starting at approximately 350.degree. C. Between 400.degree. and 500.degree. C. and at methane pressures .ltoreq.1 atmosphere the rate of methane conversion increases steadily with typical conversion efficiencies at 500.degree. C. approaching 50% and selectivity to the production of C.sub.2+ hydrocarbons approaching 100%. The activation mechanism is based on reduction of the transition metal(III) form of the molecular sieve to the transition metal(II) form with accompanying oxidative dehydrogenation of the methane. Reoxidation of the - transition metal(II) form to the transition metal(III) form can be done either chemically (e.g., using O.sub.2) or electrochemically.

    18. SSI (soil-structure interactions) and structural benchmarks

      SciTech Connect (OSTI)

      Philippacopoulos, A.J.; Miller, C.A.; Costantino, C.J.; Graves, H.

      1986-01-01

      This paper presents the latest results of the ongoing program entitled, ''Standard Problems for Structural Computer Codes'', currently being worked on at BNL for the USNRC, Office of Nuclear Regulatory Research. During FY 1986, efforts were focussed on three tasks, namely, (1) an investigation of ground water effects on the response of Category I structures, (2) the Soil-Structure Interaction Workshop and (3) studies on structural benchmarks associated with Category I structures. The objective of the studies on ground water effects is to verify the applicability and the limitations of the SSI methods currently used by the industry in performing seismic evaluations of nuclear plants which are located at sites with high water tables. In a previous study by BNL (NUREG/CR-4588), it has been concluded that the pore water can influence significantly the soil-structure interaction process. This result, however, is based on the assumption of fully saturated soil profiles. Consequently, the work was further extended to include cases associated with variable water table depths. In this paper, results related to ''cut-off'' depths beyond which the pore water effects can be ignored in seismic calculations, are addressed. Comprehensive numerical data are given for soil configurations typical to those encountered in nuclear plant sites. These data were generated by using a modified version of the SLAM code which is capable of handling problems related to the dynamic response of saturated soils.

    19. NREL Takes First In-Depth Look at Solar Project Completion Timelines - News

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

      Releases | NREL Takes First In-Depth Look at Solar Project Completion Timelines Report examines new data to show how long the PV interconnection process takes in the U.S. February 11, 2015 The Energy Department's National Renewable Energy Laboratory (NREL) has gathered and analyzed data for more than 30,000 solar photovoltaic (PV) installations across the United States to better understand how interconnection regulations align with actual project completion timelines. The findings indicate

    20. DOE/SC-ARM/TR-129 Aerosol Optical Depth Value-Added Product

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

      9 Aerosol Optical Depth Value-Added Product A Koontz C Flynn G Hodges J Michalsky J Barnard March 2013 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use

    1. Evaluation of the Effective Moisture Penetration Depth Model for Estimating Moisture Buffering in Buildings

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

      Evaluation of the Effective Moisture Penetration Depth Model for Estimating Moisture Buffering in Buildings J. Woods, J. Winkler, and D. Christensen National Renewable Energy Laboratory Technical Report NREL/TP-5500-57441 January 2013 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 15013 Denver West Parkway Golden, Colorado 80401

    2. Small-angle Compton Scattering to Determine the Depth of a Radioactive Source in Matter

      SciTech Connect (OSTI)

      Oberer, R. B.; Gunn, C. A.; Chiang, L. G.; Valiga, R. E.; Cantrell, J. A.

      2011-04-01

      A gamma-ray peak in a spectrum is often accompanied by a discontinuity in the Compton continuum at the peak. The Compton continuum results from Compton scattering in the detector. The discontinuity at a peak results from small-angle Compton scattering by the gamma rays in matter situated directly between the gamma-ray source and the detector. The magnitude of this discontinuity with respect to the gamma-ray peak is therefore an indicator of the amount of material or shielding between the gamma-ray source and the detector. This small-angle scattering was used to determine the depth of highly-enriched uranium (HEU) solution standards in a concrete floor mockup. The empirical results of the use of this small-angle scattering discontinuity in a concrete floor experiment will be described. A Monte Carlo calculation of the experiment will also be described. In addition, the depth determined from small-angle scattering was used in conjunction with differential attenuation to more accurately measure the uranium content of the mockup. Following these empirical results, the theory of small-angle scattering will be discussed. The magnitude of the discontinuity compared to the peak count rate is directly related to the depth of the gamma-ray source in matter. This relation can be described by relatively simple mathematical expressions. This is the first instance that we are aware of in which the small-angle Compton scattering has been used to determine the depth of a radioactive source. Furthermore this is the first development of the theoretical expressions for the magnitude of the small-angle scattering discontinuity.

    3. Tsunami and acoustic-gravity waves in water of constant depth

      SciTech Connect (OSTI)

      Hendin, Gali; Stiassnie, Michael

      2013-08-15

      A study of wave radiation by a rather general bottom displacement, in a compressible ocean of otherwise constant depth, is carried out within the framework of a three-dimensional linear theory. Simple analytic expressions for the flow field, at large distance from the disturbance, are derived. Realistic numerical examples indicate that the Acoustic-Gravity waves, which significantly precede the Tsunami, are expected to leave a measurable signature on bottom-pressure records that should be considered for early detection of Tsunami.

    4. Method for the depth corrected detection of ionizing events from a co-planar grids sensor

      DOE Patents [OSTI]

      De Geronimo, Gianluigi; Bolotnikov, Aleksey E.; Carini, Gabriella

      2009-05-12

      A method for the detection of ionizing events utilizing a co-planar grids sensor comprising a semiconductor substrate, cathode electrode, collecting grid and non-collecting grid. The semiconductor substrate is sensitive to ionizing radiation. A voltage less than 0 Volts is applied to the cathode electrode. A voltage greater than the voltage applied to the cathode is applied to the non-collecting grid. A voltage greater than the voltage applied to the non-collecting grid is applied to the collecting grid. The collecting grid and the non-collecting grid are summed and subtracted creating a sum and difference respectively. The difference and sum are divided creating a ratio. A gain coefficient factor for each depth (distance between the ionizing event and the collecting grid) is determined, whereby the difference between the collecting electrode and the non-collecting electrode multiplied by the corresponding gain coefficient is the depth corrected energy of an ionizing event. Therefore, the energy of each ionizing event is the difference between the collecting grid and the non-collecting grid multiplied by the corresponding gain coefficient. The depth of the ionizing event can also be determined from the ratio.

    5. Letter Report: Borehole Flow and Horizontal Hydraulic Conductivity with Depth at Well ER-12-4

      SciTech Connect (OSTI)

      Phil L. Oberlander; Charles E. Russell

      2005-12-31

      Borehole flow and fluid temperature during pumping were measured at well ER-12-4 at the Nevada Test Site in Nye County, Nevada. This well was constructed to characterize the carbonate aquifer. The well is cased from land surface to the total depth at 1,132 m (3,713 ft bgs) below ground surface (bgs). The screened section of the well consists of alternating sections of slotted well screen and blank casing from 948 to 1,132 m bgs (3,111 to 3,713 ft bgs). Borehole flow velocity (LT-1) with depth was measured with an impeller flowmeter from the top of the screened section to the maximum accessible depth while the well was pumped and under ambient conditions. A complicating factor to data interpretation is that the well was not filter packed and there is upward and downward vertical flow in the open annulus under ambient and pumping conditions. The open annulus in the well casing likely causes the calculated borehole flow rates being highly nonrepresentative of inflow from the formation. Hydraulic conductivities calculated under these conditions would require unsupportable assumptions and would be subject to very large uncertainties. Borehole hydraulic conductivities are not presented under these conditions.

    6. IMPROVED V II log(gf) VALUES, HYPERFINE STRUCTURE CONSTANTS, AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

      SciTech Connect (OSTI)

      Wood, M. P.; Lawler, J. E.; Den Hartog, E. A.; Sneden, C.; Cowan, J. J. E-mail: jelawler@wisc.edu E-mail: chris@verdi.as.utexas.edu

      2014-10-01

      New experimental absolute atomic transition probabilities are reported for 203 lines of V II. Branching fractions are measured from spectra recorded using a Fourier transform spectrometer and an echelle spectrometer. The branching fractions are normalized with radiative lifetime measurements to determine the new transition probabilities. Generally good agreement is found between this work and previously reported V II transition probabilities. Two spectrometers, independent radiometric calibration methods, and independent data analysis routines enable a reduction in systematic uncertainties, in particular those due to optical depth errors. In addition, new hyperfine structure constants are measured for selected levels by least squares fitting line profiles in the FTS spectra. The new V II data are applied to high resolution visible and UV spectra of the Sun and metal-poor star HD 84937 to determine new, more accurate V abundances. Lines covering a range of wavelength and excitation potential are used to search for non-LTE effects. Very good agreement is found between our new solar photospheric V abundance, log ε(V) = 3.95 from 15 V II lines, and the solar-system meteoritic value. In HD 84937, we derive [V/H] = –2.08 from 68 lines, leading to a value of [V/Fe] = 0.24.

    7. Structural and mechanical properties of thorium carbide

      SciTech Connect (OSTI)

      Aynyas, Mahendra; Pataiya, Jagdeesh; Arya, B. S.; Singh, A.; Sanyal, S. P.

      2015-06-24

      We have investigated the cohesive energies, equilibrium lattice constants, pressure-volume relationship, phase transition pressure and elastic constant for thorium carbide using an interionic potential theory with modified ionic charge, which includes Coulomb screening effect due to d-electrons. This compound undergoes structural phase transition from NaCl (B{sub 1}) to CsCl (B{sub 2}) structure at high pressure 40 GPa. We have also calculated bulk, Young, and shear moduli, Poisson ratio and anisotropic ratio in NaCl (B{sub 1}) structure and compared them with other experimental and theoretical results which show a good agreement.

    8. Method for forming suspended micromechanical structures

      DOE Patents [OSTI]

      Fleming, James G. (Albuquerque, NM)

      2000-01-01

      A micromachining method is disclosed for forming a suspended micromechanical structure from {111} crystalline silicon. The micromachining method is based on the use of anisotropic dry etching to define lateral features of the structure which are etched down into a {111}-silicon substrate to a first etch depth, thereby forming sidewalls of the structure. The sidewalls are then coated with a protection layer, and the substrate is dry etched to a second etch depth to define a spacing of the structure from the substrate. A selective anisotropic wet etchant (e.g. KOH, EDP, TMAH, NaOH or CsOH) is used to laterally undercut the structure between the first and second etch depths, thereby forming a substantially planar lower surface of the structure along a {111} crystal plane that is parallel to an upper surface of the structure. The lateral extent of undercutting by the wet etchant is controlled and effectively terminated by either timing the etching, by the location of angled {111}-silicon planes or by the locations of preformed etch-stops. This present method allows the formation of suspended micromechanical structures having large vertical dimensions and large masses while allowing for detailed lateral features which can be provided by dry etch definition. Additionally, the method of the present invention is compatible with the formation of electronic circuitry on the substrate.

    9. Knoxville Area Transit: Propane Hybrid Electric Trolleys

      SciTech Connect (OSTI)

      Not Available

      2005-04-01

      A 2-page fact sheet summarizing the evaluation done by the U.S. Department of Energy's Advanced Vehicle Testing Activity on the Knoxville Area Transit's use of propane hybrid electric trolleys.

    10. LM Records and Information Management Transition Guidance (May 2016) |

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

      Department of Energy Records and Information Management Transition Guidance (May 2016) LM Records and Information Management Transition Guidance (May 2016) This guidance document establishes a framework for developing a Records and Information Management Transition Plan as part of the overall transition effort for a legacy site. LM Records and Information Management Transition Guidance (May 2016) (1.47 MB) More Documents & Publications Information and Records Management Transition

    11. Pion-Photon Transition Distribution Amplitudes

      SciTech Connect (OSTI)

      Courtoy, A.; Noguera, S.

      2008-08-29

      The newly introduced Transition Distribution Amplitudes (TDAs) are discussed for the {pi}-{gamma} transitions. Relations between {pi}-{gamma} and {gamma}-{pi} TDAs for different cases are given. Numerical values for the {pi}-{gamma} TDAs in different models are compared. GPD's features are extended to TDAs and the role of PCAC highlighted. We give hints for the evaluation of cross sections for meson pair production in our approach.

    12. DOE'S geothermal division: A period of transition

      SciTech Connect (OSTI)

      Jelacic, Allan J.; Reed, Marshall

      1996-01-24

      The transition that the Department of Energy's geothemal research program is undergoing is discussed. This transitional period began last year and will continue at least through final implementation of the Department's reorganization and downsizing. Current and recently completed R&D programs are reviewed. New initiatives are outlined. The foci and direction of the Division's activities of particular interest to the geothermal research community are addressed.

    13. Ferroelasticity and domain physics in two-dimensional transition metal dichalcogenide monolayers

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

      Li, Wenbin; Li, Ju

      2016-02-24

      Monolayers of transition metal dichalcogenides can exist in several structural polymorphs, including 2H, 1T and 1T'. The low-symmetry 1T' phase has three orientation variants, resulting from the three equivalent directions of Peierls distortion in the parental 1T phase. Using first-principles calculations, we predict that mechanical strain can switch the relative thermodynamic stability between the orientation variants of the 1T' phase. We find that such strain-induced variant switching only requires a few percent elastic strain, which is eminently achievable experimentally with transition metal dichalcogenide monolayers. Calculations indicate that the transformation barrier associated with such variant switching is small (<0.2 eV permore » chemical formula unit), suggesting that strain-induced variant switching can happen under laboratory conditions. Furthermore, monolayers of transition metal dichalcogenides with 1T' structure therefore have the potential to be ferroelastic and shape memory materials with interesting domain physics.« less

    14. Band gap tuning in transition metal oxides by site-specific substitution

      DOE Patents [OSTI]

      Lee, Ho Nyung; Chisholm, Jr., Matthew F; Jellison, Jr., Gerald Earle; Singh, David J; Choi, Woo Seok

      2013-12-24

      A transition metal oxide insulator composition having a tuned band gap includes a transition metal oxide having a perovskite or a perovskite-like crystalline structure. The transition metal oxide includes at least one first element selected form the group of Bi, Ca, Ba, Sr, Li, Na, Mg, K, Pb, and Pr; and at least one second element selected from the group of Ti, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ru, Rh, Hf, Ta, W, Re, Os, Ir, and Pt. At least one correlated insulator is integrated into the crystalline structure, including REMO.sub.3, wherein RE is at least one Rare Earth element, and wherein M is at least one element selected from the group of Co, V, Cr, Ni, Mn, and Fe. The composition is characterized by a band gap of less of 4.5 eV.

    15. Anomalously large isotope effect in the glass transition of water

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

      Gainaru, Catalin; Agapov, Alexander L.; Fuentes-Landete, Violeta; Amann-Winkel, Katrin; Nelson, Helge; Köster, Karsten W.; Kolesnikov, Alexander I.; Novikov, Vladimir N.; Richert, Ranko; Böhmer, Roland; et al

      2014-11-24

      Here we present the discovery of an unusually large isotope effect in the structural relaxation and the glass transition temperature Tg of water. Dielectric relaxation spectroscopy of low-density as well as of vapor deposited amorphous water reveal Tg differences of 10±2K between H2O and D2O, sharply contrasting with other hydrogen bonded liquids for which H/D exchange increases Tg by typically less than 1K. We show that the large isotope effect and the unusual variation of relaxation times in water at low temperatures can be explained in terms of quantum effects. Thus, our findings shed new light on water's peculiar low-temperaturemore » dynamics and the possible role of quantum effects in its structural relaxation, and possibly in dynamics of other low molecular weight liquids.« less

    16. LM Records and Information Management Transition Guidance (January 2015)

      Broader source: Energy.gov [DOE]

      This guidance document establishes a framework for developing a Records and Information Management Transition Plan as part of the overall transition effort for a legacy site.

    17. Walker-Lane Transition Zone Geothermal Region | Open Energy Informatio...

      Open Energy Info (EERE)

      At Walker-Lane Transitional Zone Region (Coolbaugh, Et Al., 2005 - 2) Direct-Current Resistivity Survey At Walker-Lane Transitional Zone Region (Pritchett,...

    18. Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation...

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

      Administration; Appendix Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration; Appendix ...

    19. United Kingdom Low Carbon Transition Plan | Open Energy Information

      Open Energy Info (EERE)

      Low Carbon Transition Plan Jump to: navigation, search Tool Summary LAUNCH TOOL Name: United Kingdom Low Carbon Transition Plan AgencyCompany Organization: United Kingdom...

    20. EBRD-The Low Carbon Transition | Open Energy Information

      Open Energy Info (EERE)

      The Low Carbon Transition Jump to: navigation, search Tool Summary LAUNCH TOOL Name: EBRD-The Low Carbon Transition AgencyCompany Organization: European Bank for Reconstruction...

    1. Integrated Market Modeling of Hydrogen Transition Scenarios with...

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

      Integrated Market Modeling of Hydrogen Transition Scenarios with HyTrans Integrated Market Modeling of Hydrogen Transition Scenarios with HyTrans Presentation by Paul Leiby of Oak ...

    2. Site Transition Framework for Long-Term Surveillance and Maintenance...

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

      for Long-Term Surveillance and Maintenance Site Transition Framework for Long-Term Surveillance and Maintenance (943.69 KB) More Documents & Publications Site Transition Framework ...

    3. Site Transition Framework for Long-Term Surveillance and Maintenance...

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

      Framework for Long-Term Surveillance and Maintenance Site Transition Framework for Long-Term Surveillance and Maintenance The Site Transition Framework (STF) provides a framework ...

    4. Hiring Our Heroes Transition and Benefits Career Fair- Baltimore...

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

      Hiring Our Heroes Transition and Benefits Career Fair- Baltimore, MD part of the 97th Annual American Legion National Convention Hiring Our Heroes Transition and Benefits Career...

    5. Unbalanced edge modes and topological phase transition in gated...

      Office of Scientific and Technical Information (OSTI)

      Unbalanced edge modes and topological phase transition in gated trilayer graphene Title: Unbalanced edge modes and topological phase transition in gated trilayer graphene Authors: ...

    6. Superconductors and Complex Transition Metal Oxides for Tunable...

      Office of Scientific and Technical Information (OSTI)

      Superconductors and Complex Transition Metal Oxides for Tunable THz Plasmonic Metamaterials Citation Details In-Document Search Title: Superconductors and Complex Transition Metal ...

    7. POLICY GUIDANCE MEMORANDUM #19 Guidance on Transition to Eliminate...

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

      9 Guidance on Transition to Eliminate FCIP (Expired) POLICY GUIDANCE MEMORANDUM 19 Guidance on Transition to Eliminate FCIP (Expired) THIS GUIDANCE HAS EXPIRED Guidance on the...

    8. Transitioning to a Utility Funded Program Environment: What Do...

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

      Program Sustainability Peer Exchange Call: Transitioning to a Utility Funded Program ... More Documents & Publications Program Sustainability Peer Exchange Call: Transitioning to ...

    9. Program Sustainability Peer Exchange Call: Transitioning to a...

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

      Program Sustainability Peer Exchange Call: Transitioning to a Utility Funded Program Environment: What Do I Need to Know? Program Sustainability Peer Exchange Call: Transitioning to ...

    10. Electronic Transitions in f-electron Metals at High Pressures...

      Office of Scientific and Technical Information (OSTI)

      Technical Report: Electronic Transitions in f-electron Metals at High Pressures: Citation Details In-Document Search Title: Electronic Transitions in f-electron Metals at High ...

    11. Graphene physics and insulator-metal transition in compressed...

      Office of Scientific and Technical Information (OSTI)

      Graphene physics and insulator-metal transition in compressed hydrogen Title: Graphene physics and insulator-metal transition in compressed hydrogen Authors: Naumov, Ivan I. ; ...

    12. Driven Skyrmions and Dynamical Transitions in Chiral Magnets...

      Office of Scientific and Technical Information (OSTI)

      Driven Skyrmions and Dynamical Transitions in Chiral Magnets Citation Details In-Document Search Title: Driven Skyrmions and Dynamical Transitions in Chiral Magnets Authors: Lin, ...

    13. Transition of Long-Term Response Action Management Requirements...

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

      Transition of Long-Term Response Action Management Requirements Transition of Long-Term Response Action Management Requirements The purpose of this memorandum is to provide you ...

    14. Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation...

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

      Administration Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration This document ...

    15. LM Records and Information Management Transition Guidance (January...

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

      2015) More Documents & Publications Information and Records Management Transition Guidance LM Environmental Policy (PO 436.1a) Site Transition Process Upon Cleanup Completion

    16. Energy Independence for North America - Transition to the Hydrogen...

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

      Independence for North America - Transition to the Hydrogen Economy Energy Independence for North America - Transition to the Hydrogen Economy 2003 DEER Conference Presentation: ...

    17. Phase transitions in ferroic and multiferroic materials (Conference...

      Office of Scientific and Technical Information (OSTI)

      Phase transitions in ferroic and multiferroic materials Citation Details In-Document Search Title: Phase transitions in ferroic and multiferroic materials You are accessing a...

    18. ?-tin?Imma?sh Phase Transitions of Germanium (Journal Article...

      Office of Scientific and Technical Information (OSTI)

      DOE PAGES Search Results Publisher's Accepted Manuscript: -tinImmash Phase Transitions of Germanium Prev Next Title: -tinImmash Phase Transitions of Germanium...

    19. Phase transitions in ferroic and multiferroic materials (Conference...

      Office of Scientific and Technical Information (OSTI)

      Phase transitions in ferroic and multiferroic materials Citation Details In-Document Search Title: Phase transitions in ferroic and multiferroic materials Authors: Saxena, Avadh B...

    20. Accelerating the Transition to Clean Energy Technologies | Department...

      Office of Environmental Management (EM)

      the Transition to Clean Energy Technologies Accelerating the Transition to Clean Energy Technologies April 5, 2011 - 2:40pm Addthis David Sandalow David Sandalow Former Under ...

    1. Effects of realistic tensor force on nuclear structure

      SciTech Connect (OSTI)

      Nakada, H.

      2012-10-20

      First-order tensor-force effects on nuclear structure are investigated in the self-consistent mean-field and RPA calculations with the M3Y-type semi-realistic interactions, which contain the realistic tensor force. The tensor force plays a key role in Z- or N-dependence of the shell structure, and in transitions involving spin degrees-of-freedom. It is demonstrated that the semi-realistic interactions successfully describe the N-dependence of the shell structure in the proton-magic nuclei (e.g. Ca and Sn), and the magnetic transitions (e.g. M1 transition in {sup 208}Pb).

    2. SunLine Transit Agency Hydrogen-Powered Transit Buses: Third...

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

      This report describes operations at SunLine Transit Agency for a protoype fuel cell bus, a prototype hydrogen hybrid interal combustion engine bus, and five new compressed...

    3. Alameda-Contra Costa Transit District Fuel Cell Transit Buses: Evalluation Results Update

      Broader source: Energy.gov [DOE]

      This report is an update to the 2007 preliminary results report on hydrogen fuel cell and diesel buses operating at Alameda-Contra Costa Transit District.

    4. Sunline Transit Agency Hydrogen-Powered Transit Buses: Evaluation Results Update

      SciTech Connect (OSTI)

      Chandler, K.; Eudy, L.

      2007-10-01

      This report provides an update on the evaluation results for hydrogen and CNG-fueled buses opertating at SunLine Transit Agency in California.

    5. Fuel Cell Transit Buses: ThunderPower Bus Evaluation at SunLine Transit

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

      Agency | Department of Energy Buses: ThunderPower Bus Evaluation at SunLine Transit Agency Fuel Cell Transit Buses: ThunderPower Bus Evaluation at SunLine Transit Agency Report details the six-month evaluation of the ThunderPower hydrogen fuel cell bus demonstrated at SunLine Transit Agency. sunline_report.pdf (1.27 MB) More Documents & Publications SunLine Test Drives Hydrogen Bus: Hydrogen Fuel Cell & Infrastructure Technologies Program, Fuel Cell Bus Demonstration Projects Fact

    6. Observed damage during Argon gas cluster depth profiles of compound semiconductors

      SciTech Connect (OSTI)

      Barlow, Anders J. Portoles, Jose F.; Cumpson, Peter J.

      2014-08-07

      Argon Gas Cluster Ion Beam (GCIB) sources have become very popular in XPS and SIMS in recent years, due to the minimal chemical damage they introduce in the depth-profiling of polymer and other organic materials. These GCIB sources are therefore particularly useful for depth-profiling polymer and organic materials, but also (though more slowly) the surfaces of inorganic materials such as semiconductors, due to the lower roughness expected in cluster ion sputtering compared to that introduced by monatomic ions. We have examined experimentally a set of five compound semiconductors, cadmium telluride (CdTe), gallium arsenide (GaAs), gallium phosphide (GaP), indium arsenide (InAs), and zinc selenide (ZnSe) and a high-? dielectric material, hafnium oxide (HfO), in their response to argon cluster profiling. An experimentally determined HfO etch rate of 0.025?nm/min (3.95??10{sup ?2}?amu/atom in ion) for 6?keV Ar gas clusters is used in the depth scale conversion for the profiles of the semiconductor materials. The assumption has been that, since the damage introduced into polymer materials is low, even though sputter yields are high, then there is little likelihood of damaging inorganic materials at all with cluster ions. This seems true in most cases; however, in this work, we report for the first time that this damage can in fact be very significant in the case of InAs, causing the formation of metallic indium that is readily visible even to the naked eye.

    7. Results of Hg speciation testing on tanks 30, 32, and 37 depth samples

      SciTech Connect (OSTI)

      Bannochie, C. J.

      2015-11-30

      The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team. The twelfth shipment of samples was designated to include 3H evaporator system Tank 30, 32, and 37 depth samples. The Tank 30 depth sample (HTF-30-15-70) was taken at 190 inches from the tank bottom and the Tank 32 depth sample (HTF-32-15-68) was taken at 89 inches from the tank bottom and both were shipped to SRNL on June 29, 2015 in an 80 mL stainless steel dip bottles. The Tank 37 surface sample (HTF-37-15-94) was taken around 253.4 inches from the tank bottom and shipped to SRNL on July 21, 2015 in an 80 mL stainless steel dip bottle. All samples were placed in the SRNL Shielded Cells and left unopened until intermediate dilutions were made on July 24, 2015 using 1.00 mL of sample diluted to 100.00 mL with deionized H2O. A 30 mL Teflon® bottle was rinsed twice with the diluted tank sample and then filled leaving as little headspace as possible. It was immediately removed from the Shielded Cells and transferred to refrigerated storage where it remained at 4 °C until final dilutions were made on October 20. A second portion of the cells diluted tank sample was poured into a shielded polyethylene bottle and transferred to Analytical Development for radiochemical analysis data needed for Hazardous Material Transportation calculations.

    8. Evaluation of the Effective Moisture Penetration Depth Model for Estimating Moisture Buffering in Buildings

      SciTech Connect (OSTI)

      Woods, J.; Winkler, J.; Christensen, D.

      2013-01-01

      This study examines the effective moisture penetration depth (EMPD) model, and its suitability for building simulations. The EMPD model is a compromise between the simple, inaccurate effective capacitance approach and the complex, yet accurate, finite-difference approach. Two formulations of the EMPD model were examined, including the model used in the EnergyPlus building simulation software. An error in the EMPD model we uncovered was fixed with the release of EnergyPlus version 7.2, and the EMPD model in earlier versions of EnergyPlus should not be used.

    9. Apparatus for in-situ calibration of instruments that measure fluid depth

      DOE Patents [OSTI]

      Campbell, Melvin D.

      1994-01-01

      The present invention provides a method and apparatus for in-situ calibration of distance measuring equipment. The method comprises obtaining a first distance measurement in a first location, then obtaining at least one other distance measurement in at least one other location of a precisely known distance from the first location, and calculating a calibration constant. The method is applied specifically to calculating a calibration constant for obtaining fluid level and embodied in an apparatus using a pressure transducer and a spacer of precisely known length. The calibration constant is used to calculate the depth of a fluid from subsequent single pressure measurements at any submerged position.

    10. Apparatus for in-situ calibration of instruments that measure fluid depth

      DOE Patents [OSTI]

      Campbell, M.D.

      1994-01-11

      The present invention provides a method and apparatus for in-situ calibration of distance measuring equipment. The method comprises obtaining a first distance measurement in a first location, then obtaining at least one other distance measurement in at least one other location of a precisely known distance from the first location, and calculating a calibration constant. The method is applied specifically to calculating a calibration constant for obtaining fluid level and embodied in an apparatus using a pressure transducer and a spacer of precisely known length. The calibration constant is used to calculate the depth of a fluid from subsequent single pressure measurements at any submerged position. 8 figures.

    11. DOE/SC-ARM/TR-133 Aerosol Optical Depth Value-Added

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

      3 Aerosol Optical Depth Value-Added Product for the SAS-He Instrument B Ermold CJ Flynn J Barnard September 2013 Version 1.0 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or

    12. Size-dependent phase transition in methylammonium lead iodide perovskite microplate crystals

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

      Li, Dehui; Wang, Gongming; Cheng, Hung -Chieh; Chen, Chih -Yen; Wu, Hao; Liu, Yuan; Huang, Yu; Duan, Xiangfeng

      2016-04-21

      Methylammonium lead iodide perovskite has attracted considerable recent interest for solution processable solar cells and other optoelectronic applications. The orthorhombic-to-tetragonal phase transition in perovskite can significantly alter its optical, electrical properties and impact the corresponding applications. Here, we report a systematic investigation of the size-dependent orthorhombic-to-tetragonal phase transition using a combined temperature-dependent optical, electrical transport and transmission electron microscopy study. Our studies of individual perovskite microplates with variable thicknesses demonstrate that the phase transition temperature decreases with reducing microplate thickness. The sudden decrease of mobility around phase transition temperature and the presence of hysteresis loops in the temperature-dependent mobility confirmmore » that the orthorhombic-to-tetragonal phase transition is a first-order phase transition. Lastly, our findings offer significant fundamental insight on the temperature-and size-dependent structural, optical and charge transport properties of perovskite materials, and can greatly impact future exploration of novel electronic and optoelectronic devices from these materials.« less

    13. STRUCtural Simulator

      Energy Science and Technology Software Center (OSTI)

      2004-07-01

      STRUC-ANL is a derivative of the FLUSTR-ANL finite element code. It contains only the structural capabilities of the original fluid-structural FLUSTR code.

    14. Structural Materials

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

      Structural Materials Development enables advanced technologies through the discovery, development, and demonstration of cost-effective advanced structural materials for use in ...

    15. Defense-in-Depth, How Department of Energy Implements Radiation Protection in Low Level Waste Disposal

      Broader source: Energy.gov [DOE]

      Defense-in-Depth, How Department of Energy Implements Radiation Protection in Low Level Waste Disposal Linda Suttora*, U.S. Department of Energy ; Andrew Wallo, U.S. Department of Energy Abstract: The United States Department of Energy (DOE) has adopted an integrated protection system for the safety of radioactive waste disposal similar to the concept of a safety case that is used internationally. This approach has evolved and been continuously improved as a result of many years of experience managing low-level waste (LLW) and mixed LLW from on-going operations, decommissioning and environmental restoration activities at 29 sites around the United States. The integrated protection system is implemented using a defense-in-depth approach taking into account the combination of natural and engineered barriers, performance objectives, long-term risk assessments, maintenance of those assessments based on the most recent information to ascertain continued compliance, site-specific waste acceptance criteria based on the risk assessment and a commitment to continuous improvement. There is also a strong component of stakeholder involvement. The integrated protection system approach will be discussed to demonstrate the commitment to safety for US DOE disposal.

    16. Microtopographic and depth controls on active layer chemistry in Arctic polygonal ground

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

      Newman, Brent D.; Throckmorton, Heather M.; Graham, David E.; Gu, Baohua; Hubbard, Susan S.; Liang, Liyuan; Wu, Yuxin; Heikoop, J. M.; Herndon, Elizabeth M.; Phelps, Tommy J.; et al

      2015-03-24

      Polygonal ground is a signature characteristic of Arctic lowlands, and carbon release from permafrost thaw can alter feedbacks to Arctic ecosystems and climate. This study describes the first comprehensive spatial examination of active layer biogeochemistry that extends across high- and low-centered, ice wedge polygons, their features, and with depth. Water chemistry measurements of 54 analytes were made on surface and active layer pore waters collected near Barrow, Alaska, USA. Significant differences were observed between high- and low-centered polygons suggesting that polygon types may be useful for landscape-scale geochemical classification. However, differences were found for polygon features (centers and troughs) formore » analytes that were not significant for polygon type, suggesting that finer-scale features affect biogeochemistry differently from polygon types. Depth variations were also significant, demonstrating important multidimensional aspects of polygonal ground biogeochemistry. These results have major implications for understanding how polygonal ground ecosystems function, and how they may respond to future change.« less

    17. Device and method for the measurement of depth of interaction using co-planar electrodes

      DOE Patents [OSTI]

      DeGeronimo, Gianluigi

      2007-09-18

      A device and method for measuring a depth of interaction of an ionizing event and improving resolution of a co-planar grid sensor (CPG) are provided. A time-of-occurrence is measured using a comparator to time the leading edge of the event pulse from the non-collecting or collecting grid. A difference signal between the grid signals obtained with a differential amplifier includes a pulse with a leading edge occurring at the time-of-detection, measured with another comparator. A timing difference between comparator outputs corresponds to the depth of interaction, calculated using a processor, which in turn weights the difference grid signal to improve spectral resolution of a CPG sensor. The device, which includes channels for grid inputs, may be integrated into an Application Specific Integrated Circuit. The combination of the device and sensor is included. An improved high-resolution CPG is provided, e.g., a gamma-ray Cadmium Zinc Telluride CPG sensor operating at room temperature.

    18. Alternative Fuel Transit Buses: DART's (Dallas Area Rapid Transit) LNG Bus Fleet Final Results

      SciTech Connect (OSTI)

      Chandler, K.; Norton, P.; Clark, N.

      2000-11-07

      In 1998, Dallas Area Rapid Transit, a public transit agency in Dallas, Texas, began operating a large fleet of heavy-duty buses powered by liquefied natural gas. As part of a $16 million commitment to alternative fuels, DART operates 139 LNG buses serviced by two new LNG fueling stations.

    19. TRANSITIONAL DISKS AND THEIR ORIGINS: AN INFRARED SPECTROSCOPIC SURVEY OF ORION A

      SciTech Connect (OSTI)

      Kim, K. H.; Watson, Dan M.; Manoj, P.; Forrest, W. J.; Arnold, Laura; Najita, Joan; Furlan, Elise; Sargent, Benjamin; Espaillat, Catherine; Muzerolle, James; Megeath, S. T.; Calvet, Nuria; Green, Joel D.

      2013-06-01

      Transitional disks are protoplanetary disks around young stars, with inner holes or gaps which are surrounded by optically thick outer, and often inner, disks. Here we present observations of 62 new transitional disks in the Orion A star-forming region. These were identified using the Spitzer Space Telescope's Infrared Spectrograph and followed up with determinations of stellar and accretion parameters using the Infrared Telescope Facility's SpeX. We combine these new observations with our previous results on transitional disks in Taurus, Chamaeleon I, Ophiuchus, and Perseus, and with archival X-ray observations. This produces a sample of 105 transitional disks of ''cluster'' age 3 Myr or less, by far the largest hitherto assembled. We use this sample to search for trends between the radial structure in the disks and many other system properties, in order to place constraints on the possible origins of transitional disks. We see a clear progression of host-star accretion rate and the different disk morphologies. We confirm that transitional disks with complete central clearings have median accretion rates an order of magnitude smaller than radially continuous disks of the same population. Pre-transitional disks-those objects with gaps that separate inner and outer disks-have median accretion rates intermediate between the two. Our results from the search for statistically significant trends, especially related to M-dot , strongly support that in both cases the gaps are far more likely to be due to the gravitational influence of Jovian planets or brown dwarfs orbiting within the gaps, than to any of the photoevaporative, turbulent, or grain-growth processes that can lead to disk dissipation. We also find that the fraction of Class II YSOs which are transitional disks is large, 0.1-0.2, especially in the youngest associations.

    20. Osborne Reynolds pipe flow: Direct simulation from laminar through gradual transition to fully developed turbulence

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

      Wu, Xiaohua; Moin, Parviz; Adrian, Ronald J.; Baltzer, Jon R.

      2015-06-15

      We report that the precise dynamics of breakdown in pipe transition is a century-old unresolved problem in fluid mechanics. We demonstrate that the abruptness and mysteriousness attributed to the Osborne Reynolds pipe transition can be partially resolved with a spatially developing direct simulation that carries weakly but finitely perturbed laminar inflow through gradual rather than abrupt transition arriving at the fully developed turbulent state. Our results with this approach show during transition the energy norms of such inlet perturbations grow exponentially rather than algebraically with axial distance. When inlet disturbance is located in the core region, helical vortex filaments evolvemore » into large-scale reverse hairpin vortices. The interaction of these reverse hairpins among themselves or with the near-wall flow when they descend to the surface from the core produces small-scale hairpin packets, which leads to breakdown. When inlet disturbance is near the wall, certain quasi-spanwise structure is stretched into a Lambda vortex, and develops into a large-scale hairpin vortex. Small-scale hairpin packets emerge near the tip region of the large-scale hairpin vortex, and subsequently grow into a turbulent spot, which is itself a local concentration of small-scale hairpin vortices. This vortex dynamics is broadly analogous to that in the boundary layer bypass transition and in the secondary instability and breakdown stage of natural transition, suggesting the possibility of a partial unification. Under parabolic base flow the friction factor overshoots Moody’s correlation. Plug base flow requires stronger inlet disturbance for transition. Finally, accuracy of the results is demonstrated by comparing with analytical solutions before breakdown, and with fully developed turbulence measurements after the completion of transition.« less

    1. Nuclear-structure studies with pions and heavy ions. Progress report, June 1, 1980-May 31, 1981

      SciTech Connect (OSTI)

      Dehnhard, D.

      1981-03-01

      Experiments performed at the Los Alamos Meson Physics Facility yielded very striking results. In inelastic pion scattering from /sup 14/C near the (3,3) resonance cross sections ratios R = sigma(..pi../sup +/)/sigma(..pi../sup -/) and R/sup -1/ = sigma(..pi../sup -/)/sigma(..pi../sup +/) were observed that are significantly larger than the free pion-nucleon values. These results were interpreted as due to strong cancellations of the neutron and proton components in the transition amplitude. Measurements of /sup 13/C(..pi..,..pi..') excitation functions between 100 and 300 MeV at two momentum transfers showed dramatically different energy dependencies for ..delta..S =0 and ..delta..S = 1 transitions. They were used to derive nuclear structure information on several highly excited states. Pion data for other nuclei (/sup 12/C, /sup 16/O, /sup 40/Ca, etc.) were analyzed and information on isospin mixing, the double-charge-exchange reaction mechanism, and the excitation of collective states was extracted. Further data were taken with a 547 MeV proton beam on /sup 13/C. The data taking for the (t,t') and (/sup 3/He,/sup 3/He') reactions at the Los Alamos Van de Graaff has been completed. The continuing studies of the heavy-ion nucleus optical potential yielded information on very systematic dependencies of the potential depths on the incident energy.

    2. Hydrogen Policy and Analyzing the Transition | Department of Energy

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

      Policy and Analyzing the Transition Hydrogen Policy and Analyzing the Transition Presentation at the Renewable Hydrogen Workshop held Nov 16, 2009, in Palm Springs, CA renewable_hydrogen_workshop_nov16_leiby.pdf (697.09 KB) More Documents & Publications Integrated Market Modeling of Hydrogen Transition Scenarios with HyTrans Hydrogen Transition Study Cost and Impacts of Policies

    3. Microwave-assisted synthesis of transition metal phosphide

      DOE Patents [OSTI]

      Viswanathan, Tito

      2014-12-30

      A method of synthesizing transition metal phosphide. In one embodiment, the method has the steps of preparing a transition metal lignosulfonate, mixing the transition metal lignosulfonate with phosphoric acid to form a mixture, and subjecting the mixture to a microwave radiation for a duration of time effective to obtain a transition metal phosphide.

    4. Draft Policy and Planning Guidance for Community Transition Activities

      Broader source: Energy.gov [DOE]

      Planning Guidance for Contractor Work Force RestructuringOffice of Worker and Community Transition 

    5. In-Transit Natural Gas Form | Department of Energy

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

      In-Transit Natural Gas Form In-Transit Natural Gas Form Excel Version of In-Transit Natural Gas Form.xlsx (11.84 KB) PDF Version of In-Transit Natural Gas Form (68.4 KB) More ...

    6. Phase transition and possible metallization in CeVO{sub 4} under pressure

      SciTech Connect (OSTI)

      Garg, Alka B.; Shanavas, K.V.; Wani, B.N.; Sharma, Surinder M.

      2013-07-15

      Phase stability of CeVO{sub 4} under pressure has been investigated using synchrotron based angle dispersive x-ray diffraction (ADXRD), electrical resistance and first principles calculations. The results indicate that the ambient zircon structure of the compound transforms to a low symmetry monoclinic monazite phase beyond 3.8 GPa with nearly 8.6% volume discontinuity. Beyond 11 GPa, the pattern could be fitted to a similar monazite structure which is about 12.7% denser and has a much larger monoclinic beta angle. On pressure release the first monoclinic phase is recovered. The electrical resistance data show a large drop in resistance with pressure indicating substantial narrowing down of the band gap. Electronic structure calculations support these observations and suggest possible pressure induced metallization in this material. - Pressure induced structural phase transition in CeVO{sub 4} as observed by x- ray diffraction (pressure vs. volume) and possible metallization in CeVO{sub 4} through electrical resistance and first principles electronic structure calculations. - Highlights: Structural and electrical behavior of CeVO{sub 4} under pressure studied using x-ray diffraction and electrical resistance measurements and first principles calculations. Two successive structural transitions confirmed by experiment and theory: zirconmonazite Imonazite II. Band gap collapse and possible metallization is indicated by electrical resistance measurements and electronic structure calculations under pressure. Novel observation of lower bulk modulus in the high pressure phase (both by experiment and calculations) explained through structural analysis.

    7. Migration depths of adult steelhead Oncorhynchus mykiss in relation to dissolved gas supersaturation in a regulated river system

      SciTech Connect (OSTI)

      Johnson, Eric L.; Clabough, Tami S.; Caudill, Christopher C.; keefer, matthew L.; Peery, Christopher A.; Richmond, Marshall C.

      2010-04-01

      Adult steelhead tagged with archival transmitters primarily migrated through a large river corridor at depths > 2 m, interspersed with frequent but short (< 5 min) periods closer to the surface. The recorded swimming depths and behaviours probably provided adequate hydrostatic compensation for the encountered supersaturated dissolved gas conditions and probably limited development of gas bubble disease (GBD). Results parallel those from a concurrent adult Chinook salmon study, except steelhead experienced greater seasonal variability and were more likely to have depth-uncompensated supersaturation exposure in some dam tailraces, perhaps explaining the higher incidence of GBD in this species.

    8. Method of boronizing transition metal surfaces

      DOE Patents [OSTI]

      Koyama, Koichiro (Hyogo, JP); Shimotake, Hiroshi (Hinsdale, IL)

      1983-01-01

      A method is presented for preparing a boride layer on a transition metal substrate for use in corrosive environments or as a harden surface in machine applications. This method is particularly useful in treating current collectors for use within a high temperature and corrosive electrochemical cell environment. A melt of a alkali metal boride tetrafluoride salt including such as KF to lower its melting point is prepared including a dissolved boron containing material, for instance NiB, MnB.sub.2, or CrB.sub.2. A transition metal to be coated is immersed in the melt at a temperature of no more than 700.degree. C. and a surface boride layer of that transition metal is formed within a period of about 24 hours on the substrate surface.

    9. Method of boronizing transition metal surfaces

      DOE Patents [OSTI]

      Koyama, Koichiro; Shimotake, Hiroshi.

      1983-08-16

      A method is presented for preparing a boride layer on a transition metal substrate for use in corrosive environments or as a harden surface in machine applications. This method is particularly useful in treating current collectors for use within a high temperature and corrosive electrochemical cell environment. A melt of a alkali metal boride tetrafluoride salt including such as KF to lower its melting point is prepared including a dissolved boron containing material, for instance NiB, MnB[sub 2], or CrB[sub 2]. A transition metal to be coated is immersed in the melt at a temperature of no more than 700 C and a surface boride layer of that transition metal is formed within a period of about 24 hours on the substrate surface. 4 figs.

    10. Entanglement across a transition to quantum chaos

      SciTech Connect (OSTI)

      Mejia-Monasterio, Carlos [Center for Nonlinear and Complex Systems, Universita degli Studi dell'Insubria, via Vallegio 11, Como 22100 (Italy); Benenti, Guliano; Casati, Giulio [Center for Nonlinear and Complex Systems, Universita degli Studi dell'Insubria, via Vallegio 11, Como 22100 (Italy); Istituto Nazionale per la Fisica della Materia, Unita di Como, via Vallegio 11, Como 22100 (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milan (Italy); Carlo, Gabriel G. [Center for Nonlinear and Complex Systems, Universita degli Studi dell'Insubria, via Vallegio 11, Como 22100 (Italy); Istituto Nazionale per la Fisica della Materia, Unita di Como, via Vallegio 11, Como 22100 (Italy)

      2005-06-15

      We study the relation between entanglement and quantum chaos in one- and two-dimensional spin-1/2 lattice models, which exhibit mixing of the noninteracting eigenfunctions and transition from integrability to quantum chaos. Contrary to what occurs in a quantum phase transition, the onset of quantum chaos is not a property of the ground state but takes place for any typical many-spin quantum state. We study bipartite and pairwise entanglement measures--namely, the reduced von Neumann entropy and the concurrence--and discuss quantum entanglement sharing. Our results suggest that the behavior of the entanglement is related to the mixing of the eigenfunctions rather than to the transition to chaos.

    11. Technical Approach and Plan for Transitioning Spent Nuclear Fuel (SNF) Project Facilities to the Environmental Restoration Program

      SciTech Connect (OSTI)

      SKELLY, W.A.

      1999-10-06

      This document describes the approach and process in which the 100-K Area Facilities are to be deactivated and transitioned over to the Environmental Restoration Program after spent nuclear fuel has been removed from the K Basins. It describes the Transition Project's scope and objectives, work breakdown structure, activity planning, estimated cost, and schedule. This report will be utilized as a planning document for project management and control and to communicate details of project content and integration.

    12. In-Transit Natural Gas | Department of Energy

      Office of Environmental Management (EM)

      Gas Form In-Transit Natural Gas Form Excel Version of In-Transit Natural Gas Form.xlsx (11.84 KB) PDF Version of In-Transit Natural Gas Form (68.4 KB) More Documents & Publications Natural Gas Imports by Pipeline into the U.S. Form Natural Gas Exports by Pipeline out of the U.S. Form In-Transit Natural Gas

      Gas In-Transit Natural Gas In-Transit Natural Gas Form (Excel) (41 KB) In-Transit Natural Gas Form (pdf) (11.87 KB) More Documents & Publications Other Imports by Truck into the

    13. Investigation of methods for the selective removal and characterization of transition metals associated with solids in the marine environment

      SciTech Connect (OSTI)

      Van Valin, R.; Morse, J.W.

      1981-02-01

      The operation of an OTEC plant will result in the mixing of large volumes of seawater from different depths within the ocean. Because suspended particulate material is intimately involved in marine food webs and transition metals, such as copper, can have toxic effects, it is important to develop a sound methodology for characterizing and quantifying transition metal behavior associated with the solid material. The characterization of solid-phase-associated transition metals in the marine environment has largely been directed at marine sediments. These studies have generally indicated that it is not possible to uniquely identify the solid phases or chemical speciation of a given metal. There are many reasons for this difficulty, but the probable major analytical problems arise from the fact that many of the transition metals of interest are present only in trace concentrations as adsorbed species on amorphous oxides or as coprecipitates. In one approach transition metals are classified according to how easily they are solubilized when exposed to different types of chemical attack, as defined in chemical extraction schemes. In this study, several of the most widely accepted extraction techniques were compared for many of the most commonly measured transition metals to a variety of marine sediments. Based on the results of this study, the sequential extraction scheme of Tessler et al. (1979) is the recommended method for the characterization of solid-phase associated transition metals. An increase of the reducing agent concentration in the intermediate step and temperature decrease with an additional HCl digestion in the residual step are recommended as improvements, based on the results of the individual extraction method studies.

    14. Hydrogen Infrastructure Transition Analysis: Milestone Report

      Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

      Hydrogen Infrastructure Transition Analysis M. Melendez and A. Milbrandt Milestone Report NREL/TP-540-38351 January 2006 Hydrogen Infrastructure Transition Analysis M. Melendez and A. Milbrandt Prepared under Task No. HY55.2200 Milestone Report NREL/TP-540-38351 January 2006 National Renewable Energy Laboratory 1617 Cole Boulevard, Golden, Colorado 80401-3393 303-275-3000 * www.nrel.gov Operated for the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy by Midwest

    15. A Controlled Phase Transition | Jefferson Lab

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

      A Controlled Phase Transition A Controlled Phase Transition August 20, 2013 Since May 18, 2012, CEBAF has not accelerated an electron. In fact, for a significant fraction of that time the accelerator, as such, did not exist. Magnets were removed from the tunnel to be refurbished and upgraded to accommodate higher 12 GeV beam energies. This was done by adding a fourth leg of steel return yoke to existing C-frame magnets. Several of the dipole arcs were completed during the six-month shutdown in

    16. ARM - Field Campaign - RS-90 Transition IOP

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

      govCampaignsRS-90 Transition IOP ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : RS-90 Transition IOP 2001.03.01 - 2001.03.30 Lead Scientist : Barry Lesht Data Availability Data will be available through normal ARM channels (e.g., the ARM Data Archive). For data sets, see below. Summary One dual sounding, flying an RS-80 and RS-90 radiosonde on the same balloon, will be performed at 20:30 Universal Time

    17. DOE Community Transition Contacts | Department of Energy

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

      About Us » Contact Us » DOE Community Transition Contacts DOE Community Transition Contacts Headquarters Tom Pauling, Acting Director Office of Legacy Management, LM-1 U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 (202) 586-1782 (202) 586-8403 (FAX) thomas.pauling@hq.doe.gov Field HANFORD Colleen French U.S. Department of Energy Richland Operations Office P.O. Box 550 A7-75 Richland, WA 99352 (509) 373-5985 (509) 373-1563 (FAX) colleen_c_french@rl.gov IDAHO NATIONAL

    18. Electric quadrupole transition probabilities for atomic lithium

      SciTech Connect (OSTI)

      elik, Gltekin; Gke, Yasin; Y?ld?z, Murat

      2014-05-15

      Electric quadrupole transition probabilities for atomic lithium have been calculated using the weakest bound electron potential model theory (WBEPMT). We have employed numerical non-relativistic HartreeFock wavefunctions for expectation values of radii and the necessary energy values have been taken from the compilation at NIST. The results obtained with the present method agree very well with the Coulomb approximation results given by Caves (1975). Moreover, electric quadrupole transition probability values not existing in the literature for some highly excited levels have been obtained using the WBEPMT.

    19. Transition undulator radiation as bright infrared sources

      SciTech Connect (OSTI)

      Kim, K.J.

      1995-02-01

      Undulator radiation contains, in addition to the usual component with narrow spectral features, a broad-band component in the low frequency region emitted in the near forward direction, peaked at an angle 1/{gamma}, where {gamma} is the relativistic factor. This component is referred to as the transition undulator radiation, as it is caused by the sudden change in the electron`s longitudinal velocity as it enters and leaves the undulator. The characteristic of the transition undulator radiation are analyzed and compared with the infrared radiation from the usual undulator harmonics and from bending magnets.

    20. Magic wavelengths for terahertz clock transitions

      SciTech Connect (OSTI)

      Zhou Xiaoji; Xu Xia; Chen Xuzong; Chen Jingbiao

      2010-01-15

      Magic wavelengths for laser trapping of boson isotopes of alkaline-earth metal atoms Sr, Ca, and Mg are investigated while considering terahertz clock transitions between the {sup 3}P{sub 0}, {sup 3}P{sub 1}, and {sup 3}P{sub 2} metastable triplet states. Our calculation shows that magic wavelengths for laser trapping do exist. This result is important because those metastable states have already been used to make accurate clocks in the terahertz frequency domain. Detailed discussions for magic wavelengths for terahertz clock transitions are given in this article.