Sample records for hydride generation atomic

  1. automated hydride generation-cryotrapping-atomic: Topics by E...

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

    Mohammad 3 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

  2. Vanadium hydride deuterium-tritium generator

    DOE Patents [OSTI]

    Christensen, Leslie D. (Livermore, CA)

    1982-01-01T23:59:59.000Z

    A pressure controlled vanadium hydride gas generator to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

  3. Vanadium hydride deuterium-tritium generator

    DOE Patents [OSTI]

    Christensen, L.D.

    1980-03-13T23:59:59.000Z

    A pressure controlled vanadium hydride gas generator was designed to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

  4. Metal Hydride Thermal Storage: Reversible Metal Hydride Thermal Storage for High-Temperature Power Generation Systems

    SciTech Connect (OSTI)

    None

    2011-12-05T23:59:59.000Z

    HEATS Project: PNNL is developing a thermal energy storage system based on a Reversible Metal Hydride Thermochemical (RMHT) system, which uses metal hydride as a heat storage material. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun is not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. PNNL’s metal hydride material can reversibly store heat as hydrogen cycles in and out of the material. In a RHMT system, metal hydrides remain stable in high temperatures (600- 800°C). A high-temperature tank in PNNL’s storage system releases heat as hydrogen is absorbed, and a low-temperature tank stores the heat until it is needed. The low-cost material and simplicity of PNNL’s thermal energy storage system is expected to keep costs down. The system has the potential to significantly increase energy density.

  5. Method of generating hydrogen-storing hydride complexes

    DOE Patents [OSTI]

    Srinivasan, Sesha S; Niemann, Michael U; Goswami, D. Yogi; Stefanakos, Elias K

    2013-05-14T23:59:59.000Z

    A ternary hydrogen storage system having a constant stoichiometric molar ratio of LiNH.sub.2:MgH.sub.2:LiBH.sub.4 of 2:1:1. It was found that the incorporation of MgH.sub.2 particles of approximately 10 nm to 20 nm exhibit a lower initial hydrogen release temperature of 150.degree. C. Furthermore, it is observed that the particle size of LiBNH quaternary hydride has a significant effect on the hydrogen sorption concentration with an optimum size of 28 nm. The as-synthesized hydrides exhibit two main hydrogen release temperatures, one around 160.degree. C. and the other around 300.degree. C., with the main hydrogen release temperature reduced from 310.degree. C. to 270.degree. C., while hydrogen is first reversibly released at temperatures as low as 150.degree. C. with a total hydrogen capacity of 6 wt. % to 8 wt. %. Detailed thermal, capacity, structural and microstructural properties have been demonstrated and correlated with the activation energies of these materials.

  6. Rapid hydrogen gas generation using reactive thermal decomposition of uranium hydride.

    SciTech Connect (OSTI)

    Kanouff, Michael P.; Van Blarigan, Peter; Robinson, David B.; Shugard, Andrew D.; Gharagozloo, Patricia E.; Buffleben, George M.; James, Scott Carlton; Mills, Bernice E.

    2011-09-01T23:59:59.000Z

    Oxygen gas injection has been studied as one method for rapidly generating hydrogen gas from a uranium hydride storage system. Small scale reactors, 2.9 g UH{sub 3}, were used to study the process experimentally. Complimentary numerical simulations were used to better characterize and understand the strongly coupled chemical and thermal transport processes controlling hydrogen gas liberation. The results indicate that UH{sub 3} and O{sub 2} are sufficiently reactive to enable a well designed system to release gram quantities of hydrogen in {approx} 2 seconds over a broad temperature range. The major system-design challenge appears to be heat management. In addition to the oxidation tests, H/D isotope exchange experiments were performed. The rate limiting step in the overall gas-to-particle exchange process was found to be hydrogen diffusion in the {approx}0.5 {mu}m hydride particles. The experiments generated a set of high quality experimental data; from which effective intra-particle diffusion coefficients can be inferred.

  7. Advanced Metal-Hydrides-Based Thermal Battery: A New Generation of High Density Thermal Battery Based on Advanced Metal Hydrides

    SciTech Connect (OSTI)

    None

    2011-12-01T23:59:59.000Z

    HEATS Project: The University of Utah is developing a compact hot-and-cold thermal battery using advanced metal hydrides that could offer efficient climate control system for EVs. The team’s innovative designs of heating and cooling systems for EVs with high energy density, low-cost thermal batteries could significantly reduce the weight and eliminate the space constraint in automobiles. The thermal battery can be charged by plugging it into an electrical outlet while charging the electric battery and it produces heat and cold through a heat exchanger when discharging. The ultimate goal of the project is a climate-controlling thermal battery that can last up to 5,000 charge and discharge cycles while substantially increasing the driving range of EVs, thus reducing the drain on electric batteries.

  8. Proposed Virtual Center for Excellence for Metal Hydride Development

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

    & Engineering Sciences Center Atoms to Continuum Proposed Virtual Center of Excellence Proposed Virtual Center of Excellence for Metal Hydride Development for Metal Hydride...

  9. Atomic-Scale Chemical, Physical and Electronic Properties of the Subsurface Hydride of Palladium

    SciTech Connect (OSTI)

    Weiss, Paul

    2014-01-20T23:59:59.000Z

    We employed low-temperature, extreme-high vacuum scanning tunneling microscopy (STM) to investigate the roles of subsurface hydride (H) and deuteride (D) in the surface reconstruction and surface reactivity of Pd{110}. Specifically, we gained the ability to tailor the surface structure of Pd{110} both by preparation method and by deposition of deuterium from the gas phase. We observed thiophene at low coverage on Pd{110} to determine its adsorption orientation and electronic structure through scanning tunneling spectroscopy (STS) – namely, conductance spectroscopy and differential conductance imaging. We developed the methods necessary to coadsorb D adatoms with thiophene molecules, and to induce the reaction of individual molecules with predefined subsurface H or D features. In the case of Pd{110}, we found a much more pronounced effect from subsurface D, as it is influenced by the surface directionality. These experiments facilitate an understanding of the role of surface and subsurface H and D in heterogeneous catalytic processes, specifically in the hydrodesulfuization (HDS) of thiophene, an important and ubiquitous component found to be detrimental to petroleum refining.

  10. Activated aluminum hydride hydrogen storage compositions and uses thereof

    DOE Patents [OSTI]

    Sandrock, Gary (Ringwood, NJ); Reilly, James (Bellport, NY); Graetz, Jason (Mastic, NY); Wegrzyn, James E. (Brookhaven, NY)

    2010-11-23T23:59:59.000Z

    In one aspect, the invention relates to activated aluminum hydride hydrogen storage compositions containing aluminum hydride in the presence of, or absence of, hydrogen desorption stimulants. The invention particularly relates to such compositions having one or more hydrogen desorption stimulants selected from metal hydrides and metal aluminum hydrides. In another aspect, the invention relates to methods for generating hydrogen from such hydrogen storage compositions.

  11. Hydride compositions

    DOE Patents [OSTI]

    Lee, Myung, W.

    1994-01-01T23:59:59.000Z

    Disclosed are a composition for use in storing hydrogen and a method for making the composition. The composition comprises a mixture of two or more hydrides, each hydride having a different series of hydrogen sorption isotherms that contribute to the overall isotherms of the mixture. The hydrides are chosen so that the isotherms of the mixture have regions wherein the H equilibrium pressure increases with increasing hydrogen, preferably linearly. The isotherms of the mixture can be adjusted by selecting hydrides with different isotherms and by varying the amounts of the individual hydrides, or both. Preferably, the mixture is made up of hydrides that have isotherms with substantially flat plateaus and in nearly equimolar amounts. The composition is activated by degassing, exposing to H, and then heating below the softening temperature of any of the constituents. When the composition is used to store hydrogen, its hydrogen content can be found simply by measuring P{sub H}{sub 2} and determining H/M from the isothermic function of the composition.

  12. atomic power generation: Topics by E-print Network

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

    a squeezed atom laser is to use Queensland, University of 420 A Silicon-Based Micro Gas Turbine Engine for Power Generation CERN Preprints Summary: This paper reports on our...

  13. Remote generation of entanglement for individual atoms via optical fibers

    E-Print Network [OSTI]

    Y. Q. Guo; H. Y. Zhong; Y. H. Zhang; H. S. Song

    2008-05-29T23:59:59.000Z

    The generation of atomic entanglement is discussed in a system that atoms are trapped in separate cavities which are connected via optical fibers. Two distant atoms can be projected to Bell-state by synchronized turning off the local laser fields and then performing a single quantum measurement by a distant controller. The distinct advantage of this scheme is that it works in a regime that $\\Delta\\approx\\kappa\\gg g$, which makes the scheme insensitive to cavity strong leakage. Moreover, the fidelity is not affected by atomic spontaneous emission.

  14. Advanced Hydride Laboratory

    SciTech Connect (OSTI)

    Motyka, T.

    1989-01-01T23:59:59.000Z

    Metal hydrides have been used at the Savannah River Tritium Facilities since 1984. However, the most extensive application of metal hydride technology at the Savannah River Site is being planned for the Replacement Tritium Facility, a $140 million facility schedules for completion in 1990 and startup in 1991. In the new facility, metal hydride technology will be used to store, separate, isotopically purify, pump, and compress hydrogen isotopes. In support of the Replacement Tritium Facility, a $3.2 million, cold,'' process demonstration facility, the Advanced Hydride Laboratory began operation in November of 1987. The purpose of the Advanced Hydride Laboratory is to demonstrate the Replacement Tritium Facility's metal hydride technology by integrating the various unit operations into an overall process. This paper will describe the Advanced Hydride Laboratory, its role and its impact on the application of metal hydride technology to tritium handling.

  15. Advanced Hydride Laboratory

    SciTech Connect (OSTI)

    Motyka, T.

    1989-12-31T23:59:59.000Z

    Metal hydrides have been used at the Savannah River Tritium Facilities since 1984. However, the most extensive application of metal hydride technology at the Savannah River Site is being planned for the Replacement Tritium Facility, a $140 million facility schedules for completion in 1990 and startup in 1991. In the new facility, metal hydride technology will be used to store, separate, isotopically purify, pump, and compress hydrogen isotopes. In support of the Replacement Tritium Facility, a $3.2 million, ``cold,`` process demonstration facility, the Advanced Hydride Laboratory began operation in November of 1987. The purpose of the Advanced Hydride Laboratory is to demonstrate the Replacement Tritium Facility`s metal hydride technology by integrating the various unit operations into an overall process. This paper will describe the Advanced Hydride Laboratory, its role and its impact on the application of metal hydride technology to tritium handling.

  16. Metal Hydrides - Science Needs

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

    with traditions in metal hydride research Metal and Ceramic Sciences Condensed Matter Physics Materials Chemistry Chemical and Biological Sciences Located on campus of Tier...

  17. Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser

    E-Print Network [OSTI]

    Chu, Shih-I

    Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields-high-order harmonic generation HHG from Ar atoms and Ar+ ions by means of the self-interaction-free time-order harmonic generation HHG is one of the most rapidly developing topics in the field of laser-atom molecule

  18. Velocity distribution measurements in atomic beams generated using laser induced back-ablation

    E-Print Network [OSTI]

    Denning, A; Lee, S; Ammonson, M; Bergeson, S D

    2008-01-01T23:59:59.000Z

    We present measurements of the velocity distribution of calcium atoms in an atomic beam generated using a dual-stage laser back-ablation apparatus. Distributions are measured using a velocity selective Doppler time-of-flight technique. They are Boltzmann-like with rms velocities corresponding to temperatures above the melting point for calcium. Contrary to a recent report in the literature, this method does not generate a sub-thermal atomic beam.

  19. atomic beams generated: Topics by E-print Network

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

    of macroscopic pair-correlated atomic beams by four-wave mixing in Bose-Einstein condensates Condensed Matter (arXiv) Summary: By colliding two Bose-Einstein condensates we...

  20. Generation of genuine $?$-type four-particle entangled state of superconducting artificial atoms with broken symmetry

    E-Print Network [OSTI]

    Chun-Ling Leng; Qi Guo; Xin Ji; Shou Zhang

    2014-12-11T23:59:59.000Z

    We propose a scheme for generating a genuine $\\chi$-type four-particle entangled state of superconducting artificial atoms with broken symmetry by using one-dimensional transmission line resonator as a data bus. The $\\Delta$-type three-level artificial atom we use in the scheme is different from natural atom and has cyclic transitions. After suitable interaction time and simple operations, the desired entangled state can be obtained. Since artificial atomic excited states and photonic states are adiabatically eliminated, our scheme is robust against the spontaneous emissions of artificial atoms and the decays of transmission line resonator.

  1. Method for preparing porous metal hydride compacts

    DOE Patents [OSTI]

    Ron, M.; Gruen, D.M.; Mendelsohn, M.H.; Sheft, I.

    1980-01-21T23:59:59.000Z

    A method for preparing porous metallic-matrix hydride compacts which can be repeatedly hydrided and dehydrided without disintegration. A mixture of a finely divided metal hydride and a finely divided matrix metal is contacted with a poison which prevents the metal hydride from dehydriding at room temperature and atmospheric pressure. The mixture of matrix metal and poisoned metal hydride is then compacted under pressure at room temperature to form porous metallic-matrix hydride compacts.

  2. Method for preparing porous metal hydride compacts

    DOE Patents [OSTI]

    Ron, Moshe (Haifa, IL); Gruen, Dieter M. (Downers Grove, IL); Mendelsohn, Marshall H. (Woodridge, IL); Sheft, Irving (Oak Park, IL)

    1981-01-01T23:59:59.000Z

    A method for preparing porous metallic-matrix hydride compacts which can be repeatedly hydrided and dehydrided without disintegration. A mixture of a finely divided metal hydride and a finely divided matrix metal is contacted with a poison which prevents the metal hydride from dehydriding at room temperature and atmospheric pressure. The mixture of matrix metal and poisoned metal hydride is then compacted under pressure at room temperature to form porous metallic-matrix hydride compacts.

  3. Hydrogen Outgassing from Lithium Hydride

    SciTech Connect (OSTI)

    Dinh, L N; Schildbach, M A; Smith, R A; Balazs1, B; McLean II, W

    2006-04-20T23:59:59.000Z

    Lithium hydride is a nuclear material with a great affinity for moisture. As a result of exposure to water vapor during machining, transportation, storage and assembly, a corrosion layer (oxide and/or hydroxide) always forms on the surface of lithium hydride resulting in the release of hydrogen gas. Thermodynamically, lithium hydride, lithium oxide and lithium hydroxide are all stable. However, lithium hydroxides formed near the lithium hydride substrate (interface hydroxide) and near the sample/vacuum interface (surface hydroxide) are much less thermally stable than their bulk counterpart. In a dry environment, the interface/surface hydroxides slowly degenerate over many years/decades at room temperature into lithium oxide, releasing water vapor and ultimately hydrogen gas through reaction of the water vapor with the lithium hydride substrate. This outgassing can potentially cause metal hydriding and/or compatibility issues elsewhere in the device. In this chapter, the morphology and the chemistry of the corrosion layer grown on lithium hydride (and in some cases, its isotopic cousin, lithium deuteride) as a result of exposure to moisture are investigated. The hydrogen outgassing processes associated with the formation and subsequent degeneration of this corrosion layer are described. Experimental techniques to measure the hydrogen outgassing kinetics from lithium hydride and methods employing the measured kinetics to predict hydrogen outgassing as a function of time and temperature are presented. Finally, practical procedures to mitigate the problem of hydrogen outgassing from lithium hydride are discussed.

  4. Entanglement generation between distant atoms by Lyapunov control

    SciTech Connect (OSTI)

    Wang Xiaoting; Schirmer, S. G. [Department of Applied Maths and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

    2009-10-15T23:59:59.000Z

    We show how to apply Lyapunov control design to the problem of entanglement creation between two atoms in distant cavities connected by optical fibers. The Lyapunov control design is optimal in the sense that the distance from the target state decreases monotonically and exponentially, and the concurrence increases accordingly. This method is far more robust than simple geometric schemes.

  5. Influence of uranium hydride oxidation on uranium metal behaviour

    SciTech Connect (OSTI)

    Patel, N.; Hambley, D. [National Nuclear Laboratory (United Kingdom); Clarke, S.A. [Sellafield Ltd (United Kingdom); Simpson, K.

    2013-07-01T23:59:59.000Z

    This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

  6. Pressure atomizer having multiple orifices and turbulent generation feature

    DOE Patents [OSTI]

    VanBrocklin, Paul G. (Pittsford, NY); Geiger, Gail E. (Caledonia, NY); Moran, Donald James (Rochester, NY); Fournier, Stephane (Rochester, NY)

    2002-01-01T23:59:59.000Z

    A pressure atomizer includes a silicon plate having a top surface and a bottom surface. A portion of the top surface defines a turbulent chamber. The turbulent chamber is peripherally bounded by the top surface of the plate. The turbulent chamber is recessed a predetermined depth relative to the top surface. The silicon plate further defines at least one flow orifice. Each flow orifice extends from the bottom surface of the silicon plate to intersect with and open into the turbulent chamber. Each flow orifice is in fluid communication with the turbulent chamber.

  7. Generation of Werner states via collective decay of coherently driven atoms

    E-Print Network [OSTI]

    Girish S. Agarwal; Kishore T. Kapale

    2005-10-13T23:59:59.000Z

    We show deterministic generation of Werner states as a steady state of the collective decay dynamics of a pair of neutral atom coupled to a leaky cavity and strong coherent drive. We also show how the scheme can be extended to generate $2N$-particle analogue of the bipartite Werner states.

  8. Thermodynamic Studies and Hydride Transfer Reactions from a Rhodium Complex to BX3 Compounds

    SciTech Connect (OSTI)

    Mock, Michael T.; Potter, Robert G.; Camaioni, Donald M.; Li, Jun; Dougherty, William G.; Kassel, W. S.; Twamley, Brendan; DuBois, Daniel L.

    2009-10-14T23:59:59.000Z

    This study examines the use of transition-metal hydride complexes that can be generated by the heterolytic cleavage of H2 gas to form B–H bonds. Specifically, these studies are focused on providing a reliable and quantitative method for determining when hydride transfer from transition-metal hydrides to three-coordinate BX3 compounds will be favorable. This involves both experimental and theoretical determinations of hydride transfer abilities. Thermodynamic hydride donor abilities (?G°H-) were determined for HRh(dmpe)2 and HRh(depe)2, where dmpe = 1,2-bis(dimethylphosphinoethane) and depe = 1,2-bis(diethylphosphinoethane), on a previously established scale in acetonitrile. This hydride donor ability was used to determine the hydride donor ability of [HBEt3]? on this scale. Isodesmic reactions between [HBEt3]? and various BX3 complexes to form BEt3 and [HBX3]? were examined computationally to determine the relative hydride affinities of various BX3 compounds. The use of these scales of hydride donor abilities and hydride affinities for transition-metal hydrides and BX3 compounds is illustrated with a few selected reactions relevant to the regeneration of ammonia borane. Our findings indicate that it is possible to form B?H bonds from B?X bonds, and the extent to which BX3 compounds are reduced by transition-metal hydride complexes forming species containing multiple B?H bonds depends on the heterolytic B?X bond energy. An example is the reduction of B(SPh)3 using HRh(dmpe)2 in the presence of triethylamine to form Et3N-BH3 in high yields. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  9. atomic hydrogen generated: Topics by E-print Network

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

    hydrogen generated First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Evidence of Catalytic Production of...

  10. Generation, characterization and use of atom-resonant indistinguishable photon pairs

    E-Print Network [OSTI]

    Morgan W. Mitchell

    2015-02-26T23:59:59.000Z

    We describe the generation of atom-resonant indistinguishable photon pairs using nonlinear optical techniques, their spectral purification using atomic filters, characterization using multi-photon interference, and application to quantum-enhanced sensing with atoms. Using either type-I or type-II cavity-enhanced spontaneous parametric down-conversion, we generate pairs of photons in the resonant modes of optical cavities with linewidths comparable to the 6 MHz natural linewidth of the D$_1$ line of atomic rubidium. The cavities and pump lasers are tuned so that emission occurs in a mode or a pair of orthogonally-polarized modes that are resonant to the D$_1$ line, at 794.7 nm. The emission from these frequency-degenerate modes is separated from other cavity emission using ultra-narrow atomic frequency filters, either a Faraday anomalous dispersion optical filter (FADOF) with a 445MHz linewidth and 57 dB of out-of-band rejection or an induced dichroism filter with an 80 MHz linewidth and $\\ge$35dB out-of-band rejection. Using the type-I source, we demonstrate interference of photon pair amplitudes against a coherent state and a new method for full characterization of the temporal wave-function of narrow-band photon pairs. With the type-II source we demonstrate high-visibility super-resolving interference, a high-fidelity atom-tuned NooN state, and quantum enhanced sensing of atoms using indistinguishable photon pairs.

  11. Erbium hydride decomposition kinetics.

    SciTech Connect (OSTI)

    Ferrizz, Robert Matthew

    2006-11-01T23:59:59.000Z

    Thermal desorption spectroscopy (TDS) is used to study the decomposition kinetics of erbium hydride thin films. The TDS results presented in this report are analyzed quantitatively using Redhead's method to yield kinetic parameters (E{sub A} {approx} 54.2 kcal/mol), which are then utilized to predict hydrogen outgassing in vacuum for a variety of thermal treatments. Interestingly, it was found that the activation energy for desorption can vary by more than 7 kcal/mol (0.30 eV) for seemingly similar samples. In addition, small amounts of less-stable hydrogen were observed for all erbium dihydride films. A detailed explanation of several approaches for analyzing thermal desorption spectra to obtain kinetic information is included as an appendix.

  12. Low density metal hydride foams

    DOE Patents [OSTI]

    Maienschein, Jon L. (Oakland, CA); Barry, Patrick E. (Pleasant Hill, CA)

    1991-01-01T23:59:59.000Z

    Disclosed is a low density foam having a porosity of from 0 to 98% and a density less than about 0.67 gm/cc, prepared by heating a mixture of powered lithium hydride and beryllium hydride in an inert atmosphere at a temperature ranging from about 455 to about 490 K for a period of time sufficient to cause foaming of said mixture, and cooling the foam thus produced. Also disclosed is the process of making the foam.

  13. Protecting and Dynamically Generating Entanglement in a Two-Atom Two-Field-Mode Model

    E-Print Network [OSTI]

    K. Sinha; N. Cummings; B. L. Hu

    2010-10-06T23:59:59.000Z

    We analyze the time evolution of quantum entanglement in a model consisting of two two-level atoms interacting with a two-mode electromagnetic field for a variety of initial states. We study two different coupling schemes motivated by the forms that can arise due to atomic separation. We observe a variety of qualitative features such as entanglement sudden death, dynamical generation, protection, and transfer between subsystems. Our quantitative analysis shows that these cases with different couplings and initial states differ significantly in these qualitative features. The multifarious behaviors in these two-mode cases suggest the importance of considering atomic separation carefully for any model where two atoms interact with a common field.

  14. Synthesis and Hydride Transfer Reactions of Cobalt and Nickel Hydride Complexes to BX3 Compounds

    SciTech Connect (OSTI)

    Mock, Michael T.; Potter, Robert G.; O'Hagan, Molly J.; Camaioni, Donald M.; Dougherty, William G.; Kassel, W. S.; DuBois, Daniel L.

    2011-12-05T23:59:59.000Z

    Hydrides of numerous transition metal complexes can be generated by the heterolytic cleavage of H{sub 2} gas such that they offer alternatives to using main group hydrides in the regeneration of ammonia borane, a compound that has been intensely studied for hydrogen storage applications. Previously, we reported that HRh(dmpe){sub 2}, dmpe = 1,2-bis(dimethylphosphinoethane) was capable of reducing a variety of BX{sub 3} compounds having hydride affinity (HA) greater than or equal to HA of BEt{sub 3}. This study examines the reactivity of less expensive cobalt and nickel hydride complexes, (HCo(dmpe){sub 2} and [HNi(dmpe){sub 2}]{sup +}), to form B-H bonds. The hydride donor abilities ({Delta}G{sub H{sup -}}{sup o}) of HCo(dmpe){sub 2} and [HNi(dmpe){sub 2}]{sup +} were positioned on a previously established scale in acetonitrile that is cross-referenced with calculated HAs of BX{sub 3} compounds. The collective data guided our selection of BX{sub 3} compounds to investigate and aided our analysis of factors that determine favorability of hydride transfer. HCo(dmpe){sub 2} was observed to transfer H{sup -} to BX{sub 3} compounds with X = H, OC{sub 6}F{sub 5} and SPh. The reaction with B(SPh){sub 3} is accompanied by formation of (BH{sub 3}){sub 2}-dmpe and (BH{sub 2}SPh){sub 2}-dmpe products that follow from reduction of multiple BSPh bonds and loss of a dmpe ligand from Co. Reactions between HCo(dmpe){sub 2} and B(SPh){sub 3} in the presence of triethylamine result in formation of Et{sub 3}N-BH{sub 2}SPh and Et{sub 3}N-BH{sub 3} with no loss of dmpe ligand. Reactions of the cationic complex [HNi(dmpe){sub 2}]{sup +} with B(SPh){sub 3} under analogous conditions give Et{sub 3}N-BH{sub 2}SPh as the final product along with the nickel-thiolate complex [Ni(dmpe){sub 2}(SPh)]{sup +}. The synthesis and characterization of HCo(dedpe){sub 2} (dedpe = diethyldiphenyl(phosphino)ethane) from H{sub 2} and a base is also discussed; including the formation of an uncommon trans dihydride species, trans-[(H{sub 2})Co(dedpe){sub 2}][BF{sub 4}].

  15. Regeneration of Aluminum Hydride - Energy Innovation Portal

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

    hydride is an attractive alternative to the traditional metal hydrides for the storage of hydrogen for its use as an energy source. Alanes use as the primary source of hydrogen has...

  16. Arc plasma generator of atomic driver for steady-state negative ion source

    SciTech Connect (OSTI)

    Ivanov, A. A.; Belchenko, Yu. I.; Davydenko, V. I. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation) [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Ivanov, I. A.; Kolmogorov, V. V.; Listopad, A. A., E-mail: a.a.listopad@inp.nsk.su; Mishagin, V. V.; Shulzhenko, G. I. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)] [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Putvinsky, S. V.; Smirnov, A. [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States)] [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States)

    2014-02-15T23:59:59.000Z

    The paper reviews the results of development of steady-state arc-discharge plasma generator with directly heated LaB{sub 6} cathode. This arc-discharge plasma generator produces a plasma jet which is to be converted into an atomic one after recombination on a metallic plate. The plate is electrically biased relative to the plasma in order to control the atom energies. Such an intensive jet of hydrogen atoms can be used in negative ion sources for effective production of negative ions on a cesiated surface of plasma grid. All elements of the plasma generator have an augmented water cooling to operate in long pulse mode or in steady state. The thermo-mechanical stresses and deformations of the most critical elements of the plasma generator were determined by simulations. Magnetic field inside the discharge chamber was optimized to reduce the local power loads. The first tests of the steady-state arc plasma generator prototype have performed in long-pulse mode.

  17. Hydrogen, lithium, and lithium hydride production

    DOE Patents [OSTI]

    Brown, Sam W; Spencer, Larry S; Phillips, Michael R; Powell, G. Louis; Campbell, Peggy J

    2014-03-25T23:59:59.000Z

    A method of producing high purity lithium metal is provided, where gaseous-phase lithium metal is extracted from lithium hydride and condensed to form solid high purity lithium metal. The high purity lithium metal may be hydrided to provide high purity lithium hydride.

  18. Two-color ghost interference with photon pairs generated in hot atoms

    SciTech Connect (OSTI)

    Ding Dongsheng; Zhou Zhiyuan; Shi Baosen; Zou Xubo; Guo Guangcan [Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026 (China)

    2012-09-15T23:59:59.000Z

    We report on an experimental observation of a two-photon ghost interference experiment. A distinguishing feature of our experiment is that the photons are generated via a non-degenerated spontaneous four-wave mixing process in a hot atomic ensemble; therefore the photon has narrow bandwidth. Besides, there is a large difference in frequency between two photons in a pair. Our works may be important to achieve more secure, large transmission capacity long-distance quantum communication.

  19. Moessbauer studies of iron hydride at high pressure

    SciTech Connect (OSTI)

    Choe, I.; Ingalls, R. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (USA)); Brown, J.M.; Sato-Sorensen, Y. (Geophysics Program, AK-50, University of Washington, Seattle, Washington 98195 (USA)); Mills, R. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (USA))

    1991-07-01T23:59:59.000Z

    We have measured {ital in} {ital situ} Moessbauer spectra of iron hydride made in a diamond anvil cell at high pressure and room temperature. The spectra show a sudden change at 3.5{plus minus}0.5 GPa from a single hyperfine pattern to a superposition of three. The former pattern results from normal {alpha}-iron with negligible hydrogen content, and the latter from residual {alpha}-iron plus newly formed iron hydride. Between 3.5 and 10.4 GPa, the extra hydride pattern have hyperfine fields for one ranging from 276 to 263 kOe, and the other, from 317 to 309 kOe. Both have isomer shifts of about 0.4 mm/sec, and negligible quadrupole splittings. X-ray studies on quenched samples have shown that iron hydride is of double hexagonal close-packed structure, whose two nonequivalent iron sites may account for the observation of two different patterns. Even allowing for the effect of volume expansion, the observed isomer shifts for the hydride are considerably more positive than those of other metallic phases of iron. At the same time, the hyperfine fields are slightly smaller than that of {alpha}-iron. As a possible explanation, one may expect a bonding of hydrogen with iron, which would result in a small reduction of 4{ital s} electrons, possibly accompanied by a small increase of 3{ital d} electrons compared with the neutral atom in metallic iron. The difference between the hyperfine fields in the two spectra are presumably due to the different symmetry at the two iron sites.

  20. atomic nano-generators actinium-225-labeled: Topics by E-print...

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  1. First-principles calculations of niobium hydride formation in superconducting radio-frequency cavities

    SciTech Connect (OSTI)

    Ford, Denise C.; Cooley, Lance D.; Seidman, David N.

    2013-09-01T23:59:59.000Z

    Niobium hydride is suspected to be a major contributor to degradation of the quality factor of niobium superconducting radio-frequency (SRF) cavities. In this study, we connect the fundamental properties of hydrogen in niobium to SRF cavity performance and processing. We modeled several of the niobium hydride phases relevant to SRF cavities and present their thermodynamic, electronic, and geometric properties determined from calculations based on density-functional theory. We find that the absorption of hydrogen from the gas phase into niobium is exothermic and hydrogen becomes somewhat anionic. The absorption of hydrogen by niobium lattice vacancies is strongly preferred over absorption into interstitial sites. A single vacancy can accommodate six hydrogen atoms in the symmetrically equivalent lowest-energy sites and additional hydrogen in the nearby interstitial sites affected by the strain field: this indicates that a vacancy can serve as a nucleation center for hydride phase formation. Small hydride precipitates may then occur near lattice vacancies upon cooling. Vacancy clusters and extended defects should also be enriched in hydrogen, potentially resulting in extended hydride phase regions upon cooling. We also assess the phase changes in the niobium-hydrogen system based on charge transfer between niobium and hydrogen, the strain field associated with interstitial hydrogen, and the geometry of the hydride phases. The results of this study stress the importance of not only the hydrogen content in niobium, but also the recovery state of niobium for the performance of SRF cavities.

  2. High-order harmonic generation in atomic hydrogen at 248 nm: Dipole-moment versus acceleration spectrum

    E-Print Network [OSTI]

    Jiang, Tsin-Fu; Chu, Shih-I

    1992-12-01T23:59:59.000Z

    We present a study of the high-order harmonic-generation (HG) spectra of atomic hydrogen at 248 nm based on the Fourier transform of the expectation values of the induced dipole moment and acceleration. The calculations ...

  3. Ab initio treatment of electron correlations in polymers: Lithium hydride chain and beryllium hydride polymer

    E-Print Network [OSTI]

    Birkenheuer, Uwe

    Ab initio treatment of electron correlations in polymers: Lithium hydride chain and berylliumH and beryllium hydride Be2H4 . First, employing a Wannier-function-based approach, the systems are studiedH and the beryllium hydride polymer Be2H4 . As a simple, but due to its ionic character, non- trivial model polymer

  4. Complex hydrides for hydrogen storage

    DOE Patents [OSTI]

    Zidan, Ragaiy

    2006-08-22T23:59:59.000Z

    A hydrogen storage material and process of forming the material is provided in which complex hydrides are combined under conditions of elevated temperatures and/or elevated temperature and pressure with a titanium metal such as titanium butoxide. The resulting fused product exhibits hydrogen desorption kinetics having a first hydrogen release point which occurs at normal atmospheres and at a temperature between 50.degree. C. and 90.degree. C.

  5. Igniter containing titanium hydride and potassium perchlorate

    DOE Patents [OSTI]

    Dietzel, Russel W. (Albuquerque, NM); Leslie, William B. (Albuquerque, NM)

    1976-01-01T23:59:59.000Z

    An explosive device is described which employs a particular titanium hydride-potassium perchlorate composition directly ignitible by an electrical bridgewire.

  6. argon hydrides: Topics by E-print Network

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

    authors 2 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

  7. aluminium hydrides: Topics by E-print Network

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

    Norman A. 3 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

  8. aluminum hydride phases: Topics by E-print Network

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

    University of 19 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

  9. Incorporation of Hydride Nuclear Fuels in Commercial Light Water Reactors

    E-Print Network [OSTI]

    Terrani, Kurt Amir

    2010-01-01T23:59:59.000Z

    1.2.1 PWRs . . . . . . . . . . . . . . . . . . . . 1.2.2Actinides Multi-Recycling in PWR Using Hydride Fuels. InRecycling in Hydride Fueled PWR Cores. Nuclear Engineering

  10. Comprehensive Thermodynamics of Nickel Hydride Bis(Diphosphine...

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

    Thermodynamics of Nickel Hydride Bis(Diphosphine) Complexes: A Predictive Model through Computations. Comprehensive Thermodynamics of Nickel Hydride Bis(Diphosphine) Complexes: A...

  11. Thermal analysis of uranium zirconium hydride fuel using a lead-bismuth gap at LWR operating temperatures

    E-Print Network [OSTI]

    Ensor, Brendan M. (Brendan Melvin)

    2012-01-01T23:59:59.000Z

    Next generation nuclear technology calls for more advanced fuels to maximize the effectiveness of new designs. A fuel currently being studied for use in advanced light water reactors (LWRs) is uranium zirconium hydride ...

  12. Diffusional exchange of isotopes in a metal hydride sphere.

    SciTech Connect (OSTI)

    Wolfer, Wilhelm G.; Hamilton, John C.; James, Scott Carlton

    2011-04-01T23:59:59.000Z

    This report describes the Spherical Particle Exchange Model (SPEM), which simulates exchange of one hydrogen isotope by another hydrogen isotope in a spherical metal hydride particle. This is one of the fundamental physical processes during isotope exchange in a bed of spherical metal particles and is thus one of the key components in any comprehensive physics-based model of exchange. There are two important physical processes in the model. One is the entropy of mixing between the two isotopes; the entropy of mixing is increased by having both isotopes randomly placed at interstitial sites on the lattice and thus impedes the exchange process. The other physical process is the elastic interaction between isotope atoms on the lattice. The elastic interaction is the cause for {beta}-phase formation and is independent of the isotope species. In this report the coupled diffusion equations for two isotopes in the {beta}-phase hydride are solved. A key concept is that the diffusion of one isotope depends not only on its concentration gradient, but also on the concentration gradient of the other isotope. Diffusion rate constants and the chemical potentials for deuterium and hydrogen in the {beta}-phase hydride are reviewed because these quantities are essential for an accurate model of the diffusion process. Finally, a summary of some of the predictions from the SPEM model are provided.

  13. The calculated rovibronic spectrum of scandium hydride, ScH

    E-Print Network [OSTI]

    Lodi, Lorenzo; Tennyson\\, Jonathan

    2015-01-01T23:59:59.000Z

    The electronic structure of six low-lying electronic states of scandium hydride, $X\\,{}^{1}\\Sigma^+$, $a\\,{}^{3}\\Delta$, $b\\,{}^{3}\\Pi$, $A\\,{}^{1}\\Delta$ $c\\,{}^{3}\\Sigma^+$, and $B\\,{}^{1}\\Pi$, is studied using multi-reference configuration interaction as a function of bond length. Diagonal and off-diagonal dipole moment, spin-orbit coupling and electronic angular momentum curves are also computed. The results are benchmarked against experimental measurements and calculations on atomic scandium. The resulting curves are used to compute a line list of molecular ro-vibronic transitions for $^{45}$ScH.

  14. Direct synthesis of catalyzed hydride compounds

    DOE Patents [OSTI]

    Gross, Karl J.; Majzoub, Eric

    2004-09-21T23:59:59.000Z

    A method is disclosed for directly preparing alkali metal aluminum hydrides such as NaAlH.sub.4 and Na.sub.3 AlH.sub.6 from either the alkali metal or its hydride, and aluminum. The hydride thus prepared is doped with a small portion of a transition metal catalyst compound, such as TiCl.sub.3, TiF.sub.3, or a mixture of these materials, in order to render them reversibly hydridable. The process provides for mechanically mixing the dry reagents under an inert atmosphere followed by charging the mixed materials with high pressure hydrogen while heating the mixture to about 125.degree. C. The method is relatively simple and inexpensive and provides reversible hydride compounds which are free of the usual contamination introduced by prior art wet chemical methods.

  15. Effects of outgassing of loader chamber walls on hydriding of thin films for commercial applications

    SciTech Connect (OSTI)

    Provo, James L., E-mail: jlprovo@verizon.net [Consultant, J.L. Provo Consulting, Trinity, Florida 34655-7179 (United States)

    2014-07-01T23:59:59.000Z

    An important aspect of understanding industrial processing is to know the characteristics of the materials used in such processes. A study was performed to determine the effects of hydriding chamber material on the degree of hydriding for the commercial production of thin film hydride targets for various research universities, commercial companies, and government national laboratories. The goal was to increase the degree of hydriding of various thin film hydrides and to study the vacuum environment during air-exposure hydriding. For this purpose, dynamic residual gas analysis during deuterium gas hydride processing was utilized with erbium thin films, employing a special set-up for direct dynamic hydride gas sampling during processing at elevated temperature and full loading gas pressure. Complete process data for (1) a copper–(1.83?wt.?%)beryllium wet hydrogen fired passivated (600?°C–1?h) externally heated pipe hydriding chamber are reported. Dynamic residual gas analysis comparisons during hydriding are presented for hydriding chambers made from (2) alumina (99.8 wt.?%), (3) copper (with an interior aluminum coating ?10 k Å thick, and (4) for a stainless-steel air-fired passivated (900?°C–1?h) chamber. Dynamic data with deuterium gas in the chamber at the hydriding temperature (450?°C) showed the presence and growth of water vapor (D{sub 2}O) and related mixed ion species(H{sub 2}O{sup +}, HDO{sup +}, D{sub 2}O{sup +}, and OD{sup +}) from hydrogen isotope exchange reactions during the 1?h process time. Peaks at mass-to-charge ratios (i.e., m/e) of 12(C{sup +}), 16(CD{sub 2}{sup +}), 17(CHD{sub 2}{sup +}), and 18(CD{sub 3}{sup +}, OD{sup +}) increased for approximately the first half hour of a 1?h hydriding process and then approach steady state. Mass-to-charge peaks at 19(HDO{sup +}) and 20(D{sub 2}O{sup +}) continue to increase throughout the process cycle. Using the m/e?=?20 (D{sub 2}O{sup +}) peak intensity from chamber (1)–Cu(1.83 wt.?%)Be as a standard, the peak intensity from chamber (4)—stainless-steel (air-fired) was 7.1× higher, indicating that the surface of stainless-steel had a larger concentration of reactive oxygen and/or water than hydrogen. The (D{sub 2}O{sup +}) peak intensity from chamber (3)—Cu (interior Al coating) was 1.55× larger and chamber (2)—alumina(99.8%) was 1.33× higher than Cu(1.83 wt.?%)Be. Thus copper–(1.83 wt.?%)beryllium was the best hydriding chamber material studied followed closely by the alumina (99.8 wt.?%) chamber. Gas take-up by Er occluder targets processed in Cu(1.83?wt.?%)Be hydriding chambers (i.e., gas/metal atomic ratios) correlate with the dynamic RGA data.

  16. Zirconium hydride containing explosive composition

    DOE Patents [OSTI]

    Walker, Franklin E. (18 Shadow Oak Rd., Danville, CA 94526); Wasley, Richard J. (4290 Colgate Way, Livermore, CA 94550)

    1981-01-01T23:59:59.000Z

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a donor additive comprising a non-explosive compound or mixture of non-explosive compounds which when subjected to an energy fluence of 1000 calories/cm.sup.2 or less is capable of releasing free radicals each having a molecular weight between 1 and 120. Exemplary donor additives are dibasic acids, polyamines and metal hydrides.

  17. A non-isothermal model of a nickelmetal hydride cell , M. Mohammedb

    E-Print Network [OSTI]

    ) to avoid oxygen gas generation during over discharge and has extra capacity to avoid hydrogen gas generation during over- charge. Since the metal hydride material gradually loses capacity through usage due. The side reaction at the positive electrode is oxygen evolu- tion and at the negative electrode oxygen

  18. Wire Wrapped Hexagonal Pin Arrays for Hydride Fueled PWRs

    E-Print Network [OSTI]

    Diller, Peter

    This work contributes to the Hydride Fuels Project, a collaborative effort between UC Berkeley and MIT

  19. Experimental generation of tripartite telecom photons via an atomic ensemble and a nonlinear waveguide

    E-Print Network [OSTI]

    Dong-Sheng Ding; Wei Zhang; Shuai Shi; Zhi-Yuan Zhou; Yan Li; Bao-Sen Shi; Guang-Can Guo

    2015-01-12T23:59:59.000Z

    Non-classical multi-photon and number states attracts many people because of their wide applications in fundamental quantum mechanics tests, quantum metrology and quantum computation, therefore it is a longstanding aim to generate such states experimentally. Here, we prepare photon triplets by using the spontaneously Raman scattering process in a hot atomic ensemble cascaded by the spontaneous parametric down conversion process in a periodical poled nonlinear waveguide, the strong temporal correlations of these three photons are observed. Our experiment represents the first combination of the different order nonlinear processes and different physical systems, showing the feasibility of such composite system in this research direction. In addition, the all photons in the prepared genuine triplet are in telecom band make them be suitable for long-distance quantum communication in optical fibre.

  20. Electrochemical process and production of novel complex hydrides

    DOE Patents [OSTI]

    Zidan, Ragaiy

    2013-06-25T23:59:59.000Z

    A process of using an electrochemical cell to generate aluminum hydride (AlH.sub.3) is provided. The electrolytic cell uses a polar solvent to solubilize NaAlH.sub.4. The resulting electrochemical process results in the formation of AlH.sub.3. The AlH.sub.3 can be recovered and used as a source of hydrogen for the automotive industry. The resulting spent aluminum can be regenerated into NaAlH.sub.4 as part of a closed loop process of AlH.sub.3 generation.

  1. Hydrogen-storing hydride complexes

    DOE Patents [OSTI]

    Srinivasan, Sesha S. (Tampa, FL); Niemann, Michael U. (Venice, FL); Goswami, D. Yogi (Tampa, FL); Stefanakos, Elias K. (Tampa, FL)

    2012-04-10T23:59:59.000Z

    A ternary hydrogen storage system having a constant stoichiometric molar ratio of LiNH.sub.2:MgH.sub.2:LiBH.sub.4 of 2:1:1. It was found that the incorporation of MgH.sub.2 particles of approximately 10 nm to 20 nm exhibit a lower initial hydrogen release temperature of 150.degree. C. Furthermore, it is observed that the particle size of LiBNH quaternary hydride has a significant effect on the hydrogen sorption concentration with an optimum size of 28 nm. The as-synthesized hydrides exhibit two main hydrogen release temperatures, one around 160.degree. C. and the other around 300.degree. C., with the main hydrogen release temperature reduced from 310.degree. C. to 270.degree. C., while hydrogen is first reversibly released at temperatures as low as 150.degree. C. with a total hydrogen capacity of 6 wt. % to 8 wt. %. Detailed thermal, capacity, structural and microstructural properties have been demonstrated and correlated with the activation energies of these materials.

  2. Intramolecular hydride migration from formyl to carbonyl and nitrene ligands

    SciTech Connect (OSTI)

    Luan, L.; Brookhart, M.; Templeton, J.L. [Univ. of North Carolina, Chapel Hill, NC (United States)

    1992-04-01T23:59:59.000Z

    Reaction of [Tp{prime}W(CO){sub 2}(NPh)][PF{sub 6}] [Tp{prime} = hydrotris(3,5-dimethylpyrazolyl)borate] with lithium borohydride at -40 {degrees}C generates Tp{prime}W(CO)(Nph)(CHO) (1), which undergoes hydride migration from carbon to nitrogen (at -70 {degrees}C, k{sub obs} = 7.2 x 10{sup -6} s{sup -1}, {Delta}G{sup {double_dagger}} = 16.5 kcal/mol, t{sub {1/2}} = 27 h) to form Tp{prime}W(CO){sub 2}(NHPh). Crossover experiments indicate that the hydride migration is intramolecular. The metal formyl intermediate is fluxional; hydride migration interconverts the formyl and carbonyl ligands. The rate constant for this degenerate migration is 40 s{sup -1} at -41 {degrees}C with {Delta}G{sup {double_dagger}} = 11.7 kcal/mol. The analogous acyl complex Tp{prime}W(CO)(Nph)[C(O)Ph] (3) has been synthesized from the reaction of [Tp{prime}W(CO){sub 2}-(NPh)][PF{sub 6}] with PhMgBr. 9 refs.

  3. Liquid suspensions of reversible metal hydrides

    DOE Patents [OSTI]

    Reilly, J.J.; Grohse, E.W.; Winsche, W.E.

    1983-12-08T23:59:59.000Z

    The reversibility of the process M + x/2 H/sub 2/ ..-->.. MH/sub x/, where M is a metal hydride former that forms a hydride MH/sub x/ in the presence of H/sub 2/, generally used to store and recall H/sub 2/, is found to proceed under a liquid, thereby to reduce contamination, provide better temperature control and provide in situ mobility of the reactants. Thus, a slurry of particles of a metal hydride former with an inert solvent is subjected to temperature and pressure controlled atmosphere containing H/sub 2/, to store hydrogen (at high pressures) and to release (at low pressures) previously stored hydrogen. The direction of the flow of the H/sub 2/ through the liquid is dependent upon the H/sub 2/ pressure in the gas phase at a given temperature. When the former is above the equilibrium absorption pressure of the respective hydride the reaction proceeds to the right, i.e., the metal hydride is formed and hydrogen is stored in the solid particle. When the H/sub 2/ pressure in the gas phase is below the equilibrium dissociation pressure of the respective hydride the reaction proceeds to the left, the metal hydride is decomposed and hydrogen is released into the gas phase.

  4. COMBUSTION DRIVEN ATOMIC FLUORINE GENERATORS FOR DF CHEMICAL LASERS Abstract -Conventional high pressure corabustors delivering atomic fluorine for DF chemical

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    compositions assuming frozen isentropic expansion and with or without heat losses in the combustor. The values production at good overall laser power. 1. INTRODUCTION Available references describing combustors for also reactants. Solid propellant com- high production of F atom by thermal equilibrium positions such as NF

  5. Characteristics of cooperative spontaneous radiation with applications to atom microscopy and coherent XUV radiation generation

    E-Print Network [OSTI]

    Chang, Juntao

    2009-05-15T23:59:59.000Z

    quicker than single atom decay, with a decay rate proportional to N(?/R)2, where N is the atom numbers, R is the size of the atom cloud, and ? is the wavelength. We call it Markovian regime because the sytem does not persist memory effect. The other regime...

  6. Metastable Metal Hydrides for Hydrogen Storage

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

    Graetz, Jason

    2012-01-01T23:59:59.000Z

    The possibility of using hydrogen as a reliable energy carrier for both stationary and mobile applications has gained renewed interest in recent years due to improvements in high temperature fuel cells and a reduction in hydrogen production costs. However, a number of challenges remain and new media are needed that are capable of safely storing hydrogen with high gravimetric and volumetric densities. Metal hydrides and complex metal hydrides offer some hope of overcoming these challenges; however, many of the high capacity “reversible” hydrides exhibit a large endothermic decomposition enthalpy making it difficult to release the hydrogen at low temperatures. Onmore »the other hand, the metastable hydrides are characterized by a low reaction enthalpy and a decomposition reaction that is thermodynamically favorable under ambient conditions. The rapid, low temperature hydrogen evolution rates that can be achieved with these materials offer much promise for mobile PEM fuel cell applications. However, a critical challenge exists to develop new methods to regenerate these hydrides directly from the reactants and hydrogen gas. This spotlight paper presents an overview of some of the metastable metal hydrides for hydrogen storage and a few new approaches being investigated to address the key challenges associated with these materials.« less

  7. METALLIC HYDRIDES. Magnetic properties of laves-phase rare earth hydrides

    E-Print Network [OSTI]

    Boyer, Edmond

    METALLIC HYDRIDES. Magnetic properties of laves-phase rare earth hydrides J. J. Rhyne and G. E on the rare earth site. The rare earth spins disorder at a temperature lower than the bulk Tc in ErFe2 H3 5 per formula unit assuming complete occupation of 3 tetrahedral sites. The heavy rare earth (RFe2

  8. Short-range order of low-coverage Ti/Al,,111...: Implications for hydrogen storage in complex metal hydrides

    E-Print Network [OSTI]

    Ciobanu, Cristian

    - sition to a hydrogen economy.1 Solid-state storage in hydrogen-rich compounds, e.g., complex hydridesShort-range order of low-coverage Ti/Al,,111...: Implications for hydrogen storage in complex metal-coverage Ti atoms on Al 111 as a model surface system for transition metal doped alanate hydrogen storage

  9. arsenic hydrides: Topics by E-print Network

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

    2005-12-02 3 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

  10. americium hydrides: Topics by E-print Network

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

    2012-01-01 3 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

  11. Incorporation of Hydride Nuclear Fuels in Commercial Light Water Reactors

    E-Print Network [OSTI]

    Terrani, Kurt Amir

    2010-01-01T23:59:59.000Z

    of Zirconium Hydride and Deuteride. Journal of Alloysof ThZr 2 hydrides and deuterides using X-ray and neutronX-ray Diffraction Deuteride - X-ray Diffraction Deuteride -

  12. Interaction of Lithium Hydride and Ammonia Borane in THF . |...

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

    Lithium Hydride and Ammonia Borane in THF . Interaction of Lithium Hydride and Ammonia Borane in THF . Abstract: The two-step reaction between LiH and NH3BH3 in THF leads to the...

  13. Optimization of hydride fueled pressurized water reactor cores

    E-Print Network [OSTI]

    Shuffler, Carter Alexander

    2004-01-01T23:59:59.000Z

    This thesis contributes to the Hydride Fuels Project, a collaborative effort between UC Berkeley and MIT aimed at investigating the potential benefits of hydride fuel use in light water reactors (LWRs). This pursuit involves ...

  14. A PROTOTYPE FOUR INCH SHORT HYDRIDE (FISH) BED AS A REPLACEMENT TRITIUM STORAGE BED

    SciTech Connect (OSTI)

    Klein, J.; Estochen, E.; Shanahan, K.; Heung, L.

    2011-02-23T23:59:59.000Z

    The Savannah River Site (SRS) tritium facilities have used 1st generation (Gen1) metal hydride storage bed assemblies with process vessels (PVs) fabricated from 3 inch nominal pipe size (NPS) pipe to hold up to 12.6 kg of LaNi{sub 4.25}Al{sub 0.75} metal hydride for tritium gas absorption, storage, and desorption for over 15 years. The 2nd generation (Gen2) of the bed design used the same NPS for the PV, but the added internal components produced a bed nominally 1.2 m long, and presented a significant challenge for heater cartridge replacement in a footprint limited glove-box. A prototype 3rd generation (Gen3) metal hydride storage bed has been designed and fabricated as a replacement candidate for the Gen2 storage bed. The prototype Gen3 bed uses a PV pipe diameter of 4 inch NPS so the bed length can be reduced below 0.7 m to facilitate heater cartridge replacement. For the Gen3 prototype bed, modeling results show increased absorption rates when using hydrides with lower absorption pressures. To improve absorption performance compared to the Gen2 beds, a LaNi{sub 4.15}Al{sub 0.85} material was procured and processed to obtain the desired pressure-composition-temperature (PCT) properties. Other bed design improvements are also presented.

  15. Generating Entanglement between Atomic Spins with Low-Noise Probing of an Optical Cavity

    E-Print Network [OSTI]

    Cox, Kevin C; Greve, Graham P; Thompson, James K

    2015-01-01T23:59:59.000Z

    Atomic projection noise limits the ultimate precision of all atomic sensors, including clocks, inertial sensors, magnetometers, etc. The independent quantum collapse of $N$ atoms into a definite state (for example spin up or down) leads to an uncertainty $\\Delta \\theta_{SQL}=1/\\sqrt{N}$ in the estimate of the quantum phase accumulated during a Ramsey sequence or its many generalizations. This phase uncertainty is referred to as the standard quantum limit. Creating quantum entanglement between the $N$ atoms can allow the atoms to partially cancel each other's quantum noise, leading to reduced noise in the phase estimate below the standard quantum limit. Recent experiments have demonstrated up to $10$~dB of phase noise reduction relative to the SQL by making collective spin measurements. This is achieved by trapping laser-cooled Rb atoms in an optical cavity and precisely measuring the shift of the cavity resonance frequency by an amount that depends on the number of atoms in spin up. Detecting the probe light ...

  16. Generating Entanglement between Atomic Spins with Low-Noise Probing of an Optical Cavity

    E-Print Network [OSTI]

    Kevin C. Cox; Joshua M. Weiner; Graham P. Greve; James K. Thompson

    2015-04-20T23:59:59.000Z

    Atomic projection noise limits the ultimate precision of all atomic sensors, including clocks, inertial sensors, magnetometers, etc. The independent quantum collapse of $N$ atoms into a definite state (for example spin up or down) leads to an uncertainty $\\Delta \\theta_{SQL}=1/\\sqrt{N}$ in the estimate of the quantum phase accumulated during a Ramsey sequence or its many generalizations. This phase uncertainty is referred to as the standard quantum limit. Creating quantum entanglement between the $N$ atoms can allow the atoms to partially cancel each other's quantum noise, leading to reduced noise in the phase estimate below the standard quantum limit. Recent experiments have demonstrated up to $10$~dB of phase noise reduction relative to the SQL by making collective spin measurements. This is achieved by trapping laser-cooled Rb atoms in an optical cavity and precisely measuring the shift of the cavity resonance frequency by an amount that depends on the number of atoms in spin up. Detecting the probe light with high total efficiency reduces excess classical and quantum back-action of the probe. Here we discuss recent progress and a technique for reducing the relative frequency noise between the probe light and the optical cavity, a key requirement for further advances.

  17. High Harmonic Generation and the Role of Atomic Orbital Wave Functions

    SciTech Connect (OSTI)

    Levesque, J. [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); INRS-Energie et Materiaux, 1650 boul. Lionel-Boulet, C.P. 1020, Varennes (Quebec) J3X 1S2 (Canada); Zeidler, D. [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Carl Zeiss SMT AG, Rudolf-Eber-Str. 2, 73447 Oberkochen (Germany); Marangos, J. P. [The Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom); Corkum, P. B.; Villeneuve, D. M. [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada)

    2007-05-04T23:59:59.000Z

    High harmonic spectra were recorded from different rare-gas atoms under identical experimental conditions. It is shown that although each atom's spectrum is different, the differences are due almost entirely to the orbital influence in the recombination step. The amplitude of the continuum electron wave packet versus kinetic energy is derived from these data and is shown to be largely independent of the atom, in agreement with models of tunnel ionization. We compare the measurements with calculations in both the length gauge and the velocity gauge and show that the two gauges imply a different de Broglie wavelength.

  18. Hydridable material for the negative electrode in a nickel-metal hydride storage battery

    DOE Patents [OSTI]

    Knosp, Bernard (Neuilly-sur-Seine, FR); Bouet, Jacques (Paris, FR); Jordy, Christian (Dourdan, FR); Mimoun, Michel (Neuilly-sur-Marne, FR); Gicquel, Daniel (Lanorville, FR)

    1997-01-01T23:59:59.000Z

    A monophase hydridable material for the negative electrode of a nickel-metal hydride storage battery with a "Lave's phase" structure of hexagonal C14 type (MgZn.sub.2) has the general formula: Zr.sub.1-x Ti.sub.x Ni.sub.a Mn.sub.b Al.sub.c Co.sub.d V.sub.e where ##EQU1##

  19. Ionic hydrogenations of hindered olefins at low temperature. Hydride transfer reactions of transition metal hydrides

    SciTech Connect (OSTI)

    Bullock, R.M.; Song, J.S. (Brookhaven National Lab., Upton, NY (United States))

    1994-09-21T23:59:59.000Z

    Sterically hindered olefins can be hydrogenated at -50[degree]C in dichloromethane using triflic acid (CF[sub 3]SO[sub 3]H) and a hydride donor. Mechanistic studies indicate that these reactions proceed by hydride transfer to the carbenium ion that is formed by protonation of the olefin. Olefins that form tertiary carbenium ions upon protonation are hydrogenated in high yields (90-100%). Styrenes generally produce lower yields of hydrogenated products (50-60%). Suitable hydride donors include HSiE[sub 3] and several transition metal carbonyl hydrides HW(CO)[sub 3]Cp, HW(CO)[sub 3]Cp[sup +], HMo-(CO)[sub 3]Cp, HMn(CO)[sub 5], HRe(CO)[sub 3], and HO[sub 3](CO)[sub 1]Cp*; Cp = [eta][sup 5]-C[sub 3]H[sub 5+], Cp* = [eta][sup 5]-C[sub 5]Me[sub 5]. A characteristic that is required for transition metal hydrides to be effective is that the cationic dihydrides (or dihydrogen complexes) that result from their protonation must have sufficient acidity to transfer a proton to the olefin, as well as sufficient thermal stability to avoid significant decomposition on the time scale of the hydrogenation reaction. Metal hydrides that fall due to insufficient stability of their protonated forms include HMo(CO)[sub 2](PPH[sub 3])Cp, HMo(CO)[sub 3]Cp*, and HFe(CO)[sub 2]Cp*. 62 refs., 2 tabs.

  20. Encapsulated Metal Hydride for Hydrogen Separation

    E-Print Network [OSTI]

    concentration feed stock, not for low concentration ­ Hydrogen economy will need hydrogen recovery from lowEncapsulated Metal Hydride for Hydrogen Separation (Formerly Separation Membrane Development) DOE Hydrogen Program 2003 Merit Review and Peer Evaluation L. Kit Heung, Jim Congdon Savannah River Technology

  1. Metal hydride fuel storage and method thereof

    DOE Patents [OSTI]

    Morse, Jeffrey D. (Martinez, CA); Jankowski, Alan F. (Livermore, CA); Yu, Conrad (Antioch, CA)

    2006-10-17T23:59:59.000Z

    Disclosed herein is a metal hydride fuel storage cartridge having integrated resistive heaters that can be used in conjunction with fuel cells such as MEMS-based fuel cells. The cartridge is fabricated using micromachining methods and thin/thick film materials synthesis techniques.

  2. Metal hydride fuel storage and method thereof

    DOE Patents [OSTI]

    Morse, Jeffrey D [Martinez, CA; Jankowski, Alan F [Livermore, CA; Yu, Conrad [Antioch, CA

    2009-05-05T23:59:59.000Z

    Disclosed herein is a metal hydride fuel storage cartridge having integrated resistive heaters that can be used in conjunction with fuel cells such as MEMS-based fuel cells. The cartridge is fabricated using micromachining methods and thin/thick film materials synthesis techniques.

  3. Development of encapsulated lithium hydride thermal energy storage for space power systems

    SciTech Connect (OSTI)

    Morris, D.G.; Foote, J.P.; Olszewski, M.

    1987-12-01T23:59:59.000Z

    Inclusion of thermal energy storage in a pulsed space power supply will reduce the mass of the heat rejection system. In this mode, waste heat generated during the brief high-power burst operation is placed in the thermal store; later, the heat in the store is dissipated to space via the radiator over the much longer nonoperational period of the orbit. Thus, the radiator required is of significantly smaller capacity. Scoping analysis indicates that use of lithium hydride as the thermal storage medium results in system mass reduction benefits for burst periods as long as 800 s. A candidate design for the thermal energy storage component utilizes lithium hydride encapsulated in either 304L stainless steel or molybdenum in a packed-bed configuration with a lithium or sodium-potassium (NaK) heat transport fluid. Key issues associated with the system design include phase-change induced stresses in the shell, lithium hydride and shell compatibility, lithium hydride dissociation and hydrogen loss from the system, void presence and movement associated with the melt-freeze process, and heat transfer limitations on obtaining the desired energy storage density. 58 refs., 40 figs., 11 tabs.

  4. Comparative investigation of third- and fifth-harmonic generation in atomic and molecular gases driven by midinfrared ultrafast laser pulses

    SciTech Connect (OSTI)

    Ni Jielei; Yao Jinping; Zeng Bin; Chu Wei; Li Guihua; Zhang Haisu; Jing Chenrui [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800-211, Shanghai 201800 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Chin, S. L. [Department of Physics, Engineering Physics and Optics, and Center for Optics, Photonics and Laser (COPL), Laval University, Laval, Quebec, G1K 7P4 (Canada); Cheng, Y.; Xu, Z. [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800-211, Shanghai 201800 (China)

    2011-12-15T23:59:59.000Z

    We report on the comparative experimental investigation on third- and fifth-harmonic generation (THG and FHG) in atomic and molecular gases driven by midinfrared ultrafast laser pulses at a wavelength of {approx}1500 nm. We observe that the conversion efficiencies of both the THG and FHG processes saturate at similar peak intensities close to {approx}1.5 x 10{sup 14} W/cm{sup 2} for argon, nitrogen, and air, whose ionization potentials are close to each other. Near the saturation intensity, the ratio of yields of the FHG and THG reaches {approx}10{sup -1} for all the gases. Our results show that high-order Kerr effect seems to exist; however, contribution from the fourth-order Kerr refractive index coefficient alone is insufficient to balance the Kerr self-focusing without the assistance of plasma generation.

  5. Characterization and High Throughput Analysis of Metal Hydrides for Hydrogen Storage

    E-Print Network [OSTI]

    Barcelo, Steven James

    2009-01-01T23:59:59.000Z

    Hydrides for Energy Storage. A.F. Andresen and A.J. Maeland,Metal Hydrides for Hydrogen Storage by Steven James BarceloMetal Hydrides for Hydrogen Storage by Steven James Barcelo

  6. Chemical Hydrides Ken Stroh, facilitator

    E-Print Network [OSTI]

    Development Approach To Deliver Economic H2 via NaBH4 NaBH4 Natural Gas Solar Energy Hydro Power H2 Catalyst and distributed generation applications could be early markets that help establish the infrastructure #12;Refining

  7. HYDRIDE-RELATED DEGRADATION OF SNF CLADDING UNDER REPOSITORY CONDITIONS

    SciTech Connect (OSTI)

    K. McCoy

    2000-12-12T23:59:59.000Z

    The purpose and scope of this analysis/model report is to analyze the degradation of commercial spent nuclear fuel (CSNF) cladding under repository conditions by the hydride-related metallurgical processes, such as delayed hydride cracking (DHC), hydride reorientation and hydrogen embrittlement, thereby providing a better understanding of the degradation process and clarifying which aspects of the process are known and which need further evaluation and investigation. The intended use is as an input to a more general analysis of cladding degradation.

  8. Project Profile: Engineering a Novel High Temperature Metal Hydride...

    Office of Environmental Management (EM)

    ELEMENTS) funding program, is developing a concept for high energy density thermochemical energy storage for concentrating solar power (CSP) using metal hydrides. These materials...

  9. Proposed Virtual Center for Excellence for Metal Hydride Development...

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

    Virtual Center for Excellence for Metal Hydride Development Presentation from the Hydrogen Storage Pre-Solicitation Meeting held June 19, 2003 in Washington, DC....

  10. Documentation of Hybrid Hydride Model for Incorporation into...

    Office of Environmental Management (EM)

    Strategy This report documents the development, demonstration and validation of a mesoscale, microstructural evolution model for simulation of zirconium hydride d-ZrH1.5...

  11. METAL HYDRIDE HYDROGEN COMPRESSORS: A REVIEW

    SciTech Connect (OSTI)

    Bowman Jr, Robert C [ORNL] [ORNL; Yartys, Dr. Volodymyr A. [Institute for Energy Technology (IFE)] [Institute for Energy Technology (IFE); Lototskyy, Dr. Michael V [University of the Western Cape, South Africa] [University of the Western Cape, South Africa; Pollet, Dr. B.G. [University of the Western Cape, South Africa

    2014-01-01T23:59:59.000Z

    Metal hydride (MH) thermal sorption compression is an efficient and reliable method allowing a conversion of energy from heat into a compressed hydrogen gas. The most important component of such a thermal engine the metal hydride material itself should possess several material features in order to achieve an efficient performance in the hydrogen compression. Apart from the hydrogen storage characteristics important for every solid H storage material (e.g. gravimetric and volumetric efficiency of H storage, hydrogen sorption kinetics and effective thermal conductivity), the thermodynamics of the metal-hydrogen systems is of primary importance resulting in a temperature dependence of the absorption/desorption pressures). Several specific features should be optimized to govern the performance of the MH-compressors including synchronisation of the pressure plateaus for multi-stage compressors, reduction of slope of the isotherms and hysteresis, increase of cycling stability and life time, together with challenges in system design associated with volume expansion of the metal matrix during the hydrogenation. The present review summarises numerous papers and patent literature dealing with MH hydrogen compression technology. The review considers (a) fundamental aspects of materials development with a focus on structure and phase equilibria in the metal-hydrogen systems suitable for the hydrogen compression; and (b) applied aspects, including their consideration from the applied thermodynamic viewpoint, system design features and performances of the metal hydride compressors and major applications.

  12. LANL/PNNL Virtual Center for Chemical Hydrides and New Concepts...

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

    LANLPNNL Virtual Center for Chemical Hydrides and New Concepts for Hydrogen Storage LANLPNNL Virtual Center for Chemical Hydrides and New Concepts for Hydrogen Storage...

  13. Method of making crack-free zirconium hydride

    DOE Patents [OSTI]

    Sullivan, Richard W. (Denver, CO)

    1980-01-01T23:59:59.000Z

    Crack-free hydrides of zirconium and zirconium-uranium alloys are produced by alloying the zirconium or zirconium-uranium alloy with beryllium, or nickel, or beryllium and scandium, or nickel and scandium, or beryllium and nickel, or beryllium, nickel and scandium and thereafter hydriding.

  14. Separation Membrane Development (Separation Using Encapsulated Metal Hydride)

    E-Print Network [OSTI]

    Separation Membrane Development (Separation Using Encapsulated Metal Hydride) L. Kit Heung Savannah: The first is to produce a sol-gel encapsulated metal hydride packing material that will a) absorbs hydrogen may be that hydrogen must come from multiple sources. These sources will include renewable (solar

  15. Generation of Free Oxygen Atoms O(3P) in Solution by Photolysis of 4-Benzoylpyridine N-Oxide

    SciTech Connect (OSTI)

    Carraher, Jack M. [Ames Laboratory; Bakac, Andreja [Ames Laboratory

    2014-08-04T23:59:59.000Z

    Laser flash photolysis of 4-benzoylpyridine N-oxide (BPyO) at 308 nm in aqueous solutions generates a triplet excited state 3BPyO* that absorbs strongly in the visible, ?max 490 and 380 nm. 3BPyO* decays with the rate law kdecay/s?1 = (3.3 ± 0.9) × 104 + (1.5 ± 0.2) × 109 [BPyO] to generate a mixture of isomeric hydroxylated benzoylpyridines, BPy(OH), in addition to small amounts of oxygen atoms, O(3P). Molecular oxygen quenches 3BPyO*, kQ = 1.4 × 109 M?1 s?1, but the yields of O(3P) increase in O2-saturated solutions to 36%. Other triplet quenchers have a similar effect, which rules out the observed 3BPyO* as a source of O(3P). It is concluded that O(3P) is produced from either 1BPyO* or a short-lived, unobserved, higher energy triplet generated directly from 1BPyO*. 3BPyO* is reduced by Fe2+ and by ABTS2? to the radical anion BPyO?? which exhibits a maximum at 510 nm, ? = 2200 M?1 cm?1. The anion engages in back electron transfer with ABTS?? with k = 1.7 × 109 M?1 s?1. The same species can be generated by reducing ground state BPyO with ?C(CH3)2OH. The photochemistry of BPyO in acetonitrile is similar to that in aqueous solutions.

  16. Porous metal hydride composite and preparation and uses thereof

    DOE Patents [OSTI]

    Steyert, W.A.; Olsen, C.E.

    1980-03-12T23:59:59.000Z

    A composite formed from large pieces of aggregate formed from (1) metal hydride (or hydride-former) powder and (2) either metal powder or plastic powder or both is prepared. The composite has large macroscopic interconnected pores (much larger than the sizes of the powders which are used) and will have a very fast heat transfer rate and low windage loss. It will be useful, for example, in heat engines, hydrogen storage devices, and refrigerator components which depend for their utility upon both a fast rate of hydriding and dehydriding. Additionally, a method of preparing the composite and a method of increasing the rates of hydriding and dehydriding of metal hydrides are also given.

  17. Porous metal hydride composite and preparation and uses thereof

    DOE Patents [OSTI]

    Steyert, William A. (Los Alamos, NM); Olsen, Clayton E. (Los Alamos, NM)

    1982-01-01T23:59:59.000Z

    A composite formed from large pieces of aggregate formed from (1) metal hydride (or hydride-former) powder and (2) either metal powder or plastic powder or both is prepared. The composite has large macroscopic interconnected pores (much larger than the sizes of the powders which are used) and will have a very fast heat transfer rate and low windage loss. It will be useful, for example, in heat engines, hydrogen storage devices, and refrigerator components which depend for their utility upon both a fast rate of hydriding and dehydriding. Additionally, a method of preparing the composite and a method of increasing the rates of hydriding and dehydriding of metal hydrides are also given.

  18. A novel plating process for microencapsulating metal hydrides

    SciTech Connect (OSTI)

    Law, H.H.; Vyas, B.; Zahurak, S.M.; Kammlott, G.W. [AT and T Bell Labs., Murray Hill, NJ (United States)

    1996-08-01T23:59:59.000Z

    One approach to increasing the lifetime of the metal hydride electrode has been the use of conventional electroless plating to produce a coating of copper or nickel on the surface of the metal hydride powders. In this paper, a novel method for microencapsulating the active electrode powders is presented. This new plating technique takes advantage of the reducing power of hydrogen already stored inside the metal hydride to plate a variety of metals onto metal hydride materials. This method greatly simplifies electroless plating for these powders, eliminating the need for stabilizers and additives typically required for conventional electroless plating solutions. Metals that can be electrolessly plated with stored hydrogen have been identified based on thermodynamic considerations. Experimentally, micrometers thick coatings of copper, silver, and nickel have been plated on several metal hydrides.

  19. Modular hydride beds for mobile applications

    SciTech Connect (OSTI)

    Malinowski, M.E.; Stewart, K.D.

    1997-08-01T23:59:59.000Z

    Design, construction, initial testing and simple thermal modeling of modular, metal hydride beds have been completed. Originally designed for supplying hydrogen to a fuel cell on a mobile vehicle, the complete bed design consists of 8 modules and is intended for use on the Palm Desert Vehicle (PDV) under development at the Schatz Energy Center, Humbolt State University. Each module contains approximately 2 kg of a commercially available, low temperature, hydride-forming metal alloy. Waste heat from the fuel cell in the form of heated water is used to desorb hydrogen from the alloy for supplying feed hydrogen to the fuel cell. In order to help determine the performance of such a modular bed system, six modules were constructed and tested. The design and construction of the modules is described in detail. Initial testing of the modules both individually and as a group showed that each module can store {approximately} 30 g of hydrogen (at 165 PSIA fill pressure, 17 C), could be filled with hydrogen in 6 minutes at a nominal, 75 standard liters/min (slm) fueling rate, and could supply hydrogen during desorption at rates of 25 slm, the maximum anticipated hydrogen fuel cell input requirement. Tests made of 5 modules as a group indicated that the behavior of the group run in parallel both in fueling and gas delivery could be directly predicted from the corresponding, single module characteristics by using an appropriate scaling factor. Simple thermal modeling of a module as an array of cylindrical, hydride-filled tubes was performed. The predictions of the model are in good agreement with experimental data.

  20. Results of NDE Technique Evaluation of Clad Hydrides

    SciTech Connect (OSTI)

    Dennis C. Kunerth

    2014-09-01T23:59:59.000Z

    This report fulfills the M4 milestone, M4FT-14IN0805023, Results of NDE Technique Evaluation of Clad Hydrides, under Work Package Number FT-14IN080502. During service, zirconium alloy fuel cladding will degrade via corrosion/oxidation. Hydrogen, a byproduct of the oxidation process, will be absorbed into the cladding and eventually form hydrides due to low hydrogen solubility limits. The hydride phase is detrimental to the mechanical properties of the cladding and therefore it is important to be able to detect and characterize the presence of this constituent within the cladding. Presently, hydrides are evaluated using destructive examination. If nondestructive evaluation techniques can be used to detect and characterize the hydrides, the potential exists to significantly increase test sample coverage while reducing evaluation time and cost. To demonstrate the viability this approach, an initial evaluation of eddy current and ultrasonic techniques were performed to demonstrate the basic ability to these techniques to detect hydrides or their effects on the microstructure. Conventional continuous wave eddy current techniques were applied to zirconium based cladding test samples thermally processed with hydrogen gas to promote the absorption of hydrogen and subsequent formation of hydrides. The results of the evaluation demonstrate that eddy current inspection approaches have the potential to detect both the physical damage induced by hydrides, e.g. blisters and cracking, as well as the combined effects of absorbed hydrogen and hydride precipitates on the electrical properties of the zirconium alloy. Similarly, measurements of ultrasonic wave velocities indicate changes in the elastic properties resulting from the combined effects of absorbed hydrogen and hydride precipitates as well as changes in geometry in regions of severe degradation. However, for both approaches, the signal responses intended to make the desired measurement incorporate a number of contributing parameters. These contributing factors need to be recognized and a means to control them or separate their contributions will be required to obtain the desired information.

  1. Metal hydride fuel storage and method thereof

    DOE Patents [OSTI]

    Morse, Jeffrey D. (Martinez, CA); Jankowski, Alan F. (Livermore, CA); Yu, Conrad (Antioch, CA)

    2010-08-10T23:59:59.000Z

    An apparatus having a first substrate having (1) a cavity, (2) one or more resistive heaters, and (3) one or more coatings forming a diffusion barrier to hydrogen; a second substrate having (1) an outlet valve comprising a pressure relief structure and (2) one or more coatings forming a diffusion barrier to hydrogen, wherein said second substrate is coupled to said first substrate forming a sealed volume in said cavity; a metal hydride material contained within said cavity; and a gas distribution system formed by coupling a microfluidic interconnect to said pressure relief structure. Additional apparatuses and methods are also disclosed.

  2. Highly Concentrated Palladium Hydrides/Deuterides; Theory

    SciTech Connect (OSTI)

    Papaconstantopoulos, Dimitrios

    2013-11-26T23:59:59.000Z

    Accomplishments are reported in these areas: tight-binding molecular dynamics study of palladium; First-principles calculations and tight-binding molecular dynamics simulations of the palladium-hydrogen system; tight-binding studies of bulk properties and hydrogen vacancies in KBH{sub 4}; tight-binding study of boron structures; development of angular dependent potentials for Pd-H; and density functional and tight-binding calculations for the light-hydrides NaAlH4 and NaBH4

  3. New generation polyphase resonant converter-modulators for the Korean atomic energy research institute

    SciTech Connect (OSTI)

    Reass, William A [Los Alamos National Laboratory; Baca, David M [Los Alamos National Laboratory; Gribble, Robert F [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    This paper will present operational data and performance parameters of the newest generation polyphase resonant high voltage converter modulator (HVCM) as developed and delivered to the KAERI 100 MeV ''PEFP'' accelerator [1]. The KAERI design realizes improvements from the SNS and SLAC designs [2]. To improve the IGBT switching performance at 20 kHz for the KAERI system, the HVCM utilizes the typical zero-voltage-switching (ZVS) at turn on and as well as artificial zero-current-switching (ZCS) at turn-off. The new technique of artificial ZCS technique should result in a 6 fold reduction of IGBT switching losses (3). This improves the HCVM conversion efficiency to better than 95% at full average power, which is 500 kW for the KAERI two klystron 105 kV, 50 A application. The artificial ZCS is accomplished by placing a resonant RLC circuit across the input busswork to the resonant boost transformer. This secondary resonant circuit provides a damped ''kick-back'' to assist in IGBT commutation. As the transformer input busswork is extremely low inductance (< 10 nH), the single RLC network acts like it is across each of the four IGBT collector-emitter terminals of the H-bridge switching network. We will review these topological improvements and the overall system as delivered to the KAERI accelerator and provide details of the operational results.

  4. OPTIMIZATION OF INTERNAL HEAT EXCHANGERS FOR HYDROGEN STORAGE TANKS UTILIZING METAL HYDRIDES

    SciTech Connect (OSTI)

    Garrison, S.; Tamburello, D.; Hardy, B.; Anton, D.; Gorbounov, M.; Cognale, C.; van Hassel, B.; Mosher, D.

    2011-07-14T23:59:59.000Z

    Two detailed, unit-cell models, a transverse fin design and a longitudinal fin design, of a combined hydride bed and heat exchanger are developed in COMSOL{reg_sign} Multiphysics incorporating and accounting for heat transfer and reaction kinetic limitations. MatLab{reg_sign} scripts for autonomous model generation are developed and incorporated into (1) a grid-based and (2) a systematic optimization routine based on the Nelder-Mead downhill simplex method to determine the geometrical parameters that lead to the optimal structure for each fin design that maximizes the hydrogen stored within the hydride. The optimal designs for both the transverse and longitudinal fin designs point toward closely-spaced, small cooling fluid tubes. Under the hydrogen feed conditions studied (50 bar), a 25 times improvement or better in the hydrogen storage kinetics will be required to simultaneously meet the Department of Energy technical targets for gravimetric capacity and fill time. These models and methodology can be rapidly applied to other hydrogen storage materials, such as other metal hydrides or to cryoadsorbents, in future work.

  5. Chemical Hydride Slurry for Hydrogen Production and Storage

    SciTech Connect (OSTI)

    McClaine, Andrew W.

    2008-09-30T23:59:59.000Z

    The purpose of this project was to investigate and evaluate the attractiveness of using a magnesium chemical hydride slurry as a hydrogen storage, delivery, and production medium for automobiles. To fully evaluate the potential for magnesium hydride slurry to act as a carrier of hydrogen, potential slurry compositions, potential hydrogen release techniques, and the processes (and their costs) that will be used to recycle the byproducts back to a high hydrogen content slurry were evaluated. A 75% MgH2 slurry was demonstrated, which was just short of the 76% goal. This slurry is pumpable and storable for months at a time at room temperature and pressure conditions and it has the consistency of paint. Two techniques were demonstrated for reacting the slurry with water to release hydrogen. The first technique was a continuous mixing process that was tested for several hours at a time and demonstrated operation without external heat addition. Further work will be required to reduce this design to a reliable, robust system. The second technique was a semi-continuous process. It was demonstrated on a 2 kWh scale. This system operated continuously and reliably for hours at a time, including starts and stops. This process could be readily reduced to practice for commercial applications. The processes and costs associated with recycling the byproducts of the water/slurry reaction were also evaluated. This included recovering and recycling the oils of the slurry, reforming the magnesium hydroxide and magnesium oxide byproduct to magnesium metal, hydriding the magnesium metal with hydrogen to form magnesium hydride, and preparing the slurry. We found that the SOM process, under development by Boston University, offers the lowest cost alternative for producing and recycling the slurry. Using the H2A framework, a total cost of production, delivery, and distribution of $4.50/kg of hydrogen delivered or $4.50/gge was determined. Experiments performed at Boston University have demonstrated the technical viability of the process and have provided data for the cost analyses that have been performed. We also concluded that a carbothermic process could also produce magnesium at acceptable costs. The use of slurry as a medium to carry chemical hydrides has been shown during this project to offer significant advantages for storing, delivering, and distributing hydrogen: • Magnesium hydride slurry is stable for months and pumpable. • The oils of the slurry minimize the contact of oxygen and moisture in the air with the metal hydride in the slurry. Thus reactive chemicals, such as lithium hydride, can be handled safely in the air when encased in the oils of the slurry. • Though magnesium hydride offers an additional safety feature of not reacting readily with water at room temperatures, it does react readily with water at temperatures above the boiling point of water. Thus when hydrogen is needed, the slurry and water are heated until the reaction begins, then the reaction energy provides heat for more slurry and water to be heated. • The reaction system can be relatively small and light and the slurry can be stored in conventional liquid fuel tanks. When transported and stored, the conventional liquid fuel infrastructure can be used. • The particular metal hydride of interest in this project, magnesium hydride, forms benign byproducts, magnesium hydroxide (“Milk of Magnesia”) and magnesium oxide. • We have estimated that a magnesium hydride slurry system (including the mixer device and tanks) could meet the DOE 2010 energy density goals. ? During the investigation of hydriding techniques, we learned that magnesium hydride in a slurry can also be cycled in a rechargeable fashion. Thus, magnesium hydride slurry can act either as a chemical hydride storage medium or as a rechargeable hydride storage system. Hydrogen can be stored and delivered and then stored again thus significantly reducing the cost of storing and delivering hydrogen. Further evaluation and development of this concept will be performed as follow-on work under a

  6. Use of Solid Hydride Fuel for Improved long-Life LWR Core Designs

    SciTech Connect (OSTI)

    Greenspan, E

    2006-04-30T23:59:59.000Z

    The primary objective of this project was to assess the feasibility of improving the performance of PWR and BWR cores by using solid hydride fuels instead of the commonly used oxide fuel. The primary measure of performance considered is the bus-bar cost of electricity (COE). Additional performance measures considered are safety, fuel bundle design simplicity – in particular for BWR’s, and plutonium incineration capability. It was found that hydride fuel can safely operate in PWR’s and BWR’s without restricting the linear heat generation rate of these reactors relative to that attainable with oxide fuel. A couple of promising applications of hydride fuel in PWR’s and BWR’s were identified: (1) Eliminating dedicated water moderator volumes in BWR cores thus enabling to significantly increase the cooled fuel rods surface area as well as the coolant flow cross section area in a given volume fuel bundle while significantly reducing the heterogeneity of BWR fuel bundles thus achieving flatter pin-by-pin power distribution. The net result is a possibility to significantly increase the core power density – on the order of 30% and, possibly, more, while greatly simplifying the fuel bundle design. Implementation of the above modifications is, though, not straightforward; it requires a design of completely different control system that could probably be implemented only in newly designed plants. It also requires increasing the coolant pressure drop across the core. (2) Recycling plutonium in PWR’s more effectively than is possible with oxide fuel by virtue of a couple of unique features of hydride fuel – reduced inventory of U-238 and increased inventory of hydrogen. As a result, the hydride fuelled core achieves nearly double the average discharge burnup and the fraction of the loaded Pu it incinerates in one pass is double that of the MOX fuel. The fissile fraction of the Pu in the discharged hydride fuel is only ~2/3 that of the MOX fuel and the discharged hydride fuel is more proliferation resistant. Preliminary feasibility assessment indicates that by replacing some of the ZrH1.6 by ThH2 it will be possible to further improve the plutonium incineration capability of PWR’s. Other possibly promising applications of hydride fuel were identified but not evaluated in this work. A number of promising oxide fueled PWR core designs were also found as spin-offs of this study: (1) The optimal oxide fueled PWR core design features smaller fuel rod diameter of D=6.5 mm and a larger pitch-to-diameter ratio of P/D=1.39 than presently practiced by industry – 9.5mm and 1.326. This optimal design can provide a 30% increase in the power density and a 24% reduction in the cost of electricity (COE) provided the PWR could be designed to have the coolant pressure drop across the core increased from the reference 29 psia to 60 psia. (2) Using wire wrapped oxide fuel rods in hexagonal fuel assemblies it is possible to design PWR cores to operate at 54% higher power density than the reference PWR design that uses grid spacers and a square lattice, provided 60 psia coolant pressure drop across the core could be accommodated. Uprating existing PWR’s to use such cores could result in 40% reduction in the COE. The optimal lattice geometry is D = 8.08 mm and P/D = 1.41. The most notable advantages of wire wraps over grid spacers are their significant lower pressure drop, higher critical heat flux and improved vibrations characteristics.

  7. ENVIRONMENTAL REACTIVITY OF SOLID STATE HYDRIDE MATERIALS

    SciTech Connect (OSTI)

    Gray, J; Donald Anton, D

    2009-04-23T23:59:59.000Z

    In searching for high gravimetric and volumetric density hydrogen storage systems, it is inevitable that higher energy density materials will be used. In order to make safe and commercially acceptable condensed phase hydrogen storage systems, it is important to understand quantitatively the risks involved in using and handling these materials and to develop appropriate mitigation strategies to handle potential material exposure events. A crucial aspect of the development of risk identification and mitigation strategies is the development of rigorous environmental reactivity testing standards and procedures. This will allow for the identification of potential risks and implementation of risk mitigation strategies. Modified testing procedures for shipping air and/or water sensitive materials, as codified by the United Nations, have been used to evaluate two potential hydrogen storage materials, 2LiBH{sub 4} {center_dot} MgH{sub 2} and NH{sub 3}BH{sub 3}. The modified U.N. procedures include identification of self-reactive substances, pyrophoric substances, and gas-emitting substances with water contact. The results of these tests for air and water contact sensitivity will be compared to the pure material components where appropriate (e.g. LiBH{sub 4} and MgH{sub 2}). The water contact tests are divided into two scenarios dependent on the hydride to water mole ratio and heat transport characteristics. Air contact tests were run to determine whether a substance will spontaneously react with air in a packed or dispersed form. In the case of the 2LiBH{sub 4} {center_dot} MgH{sub 2} material, the results from the hydride mixture compared to the pure materials results showed the MgH{sub 2} to be the least reactive component and LiBH{sub 4} the more reactive. The combined 2LiBH{sub 4} {center_dot} MgH{sub 2} resulted in a material having environmental reactivity between these two materials. Relative to 2LiBH{sub 4} {center_dot} MgH{sub 2}, the chemical hydride NH{sub 3}BH{sub 3} was observed to be less environmentally reactive.

  8. Process for production of a metal hydride

    DOE Patents [OSTI]

    Allen, Nathan Tait; Butterick, III, Robert; Chin, Arthur Achhing; Millar, Dean Michael; Molzahn, David Craig

    2014-08-12T23:59:59.000Z

    A process for production of a metal hydride compound MH.sub.x, wherein x is one or two and M is an alkali metal, Be or Mg. The process comprises combining a compound of formula (R.sup.1O).sub.xM with aluminum, hydrogen and at least one metal selected from among titanium, zirconium, hafnium, niobium, vanadium, tantalum and iron to produce a compound of formula MH.sub.x. R.sup.1 is phenyl or phenyl substituted by at least one alkyl or alkoxy group. A mole ratio of aluminum to (R.sup.1O).sub.xM is from 0.1:1 to 1:1. The catalyst is present at a level of at least 200 ppm based on weight of aluminum.

  9. Ni/metal hydride secondary element

    DOE Patents [OSTI]

    Bauerlein, Peter

    2005-04-19T23:59:59.000Z

    A Ni/metal hydride secondary element having a positive nickel hydroxide electrode, a negative electrode having a hydrogen storage alloy, and an alkaline electrolyte, the positive electrode, provided with a three-dimensional metallic conductive structure, also contains an aluminum compound which is soluble in the electrolyte, in addition to nickel hydroxide and cobalt oxide. The aluminum compound is aluminum hydroxide and/or aluminum oxide, and the mass of the aluminum compound which is present in the positive bulk material mixture is 0.1 to 2% by weight relative to the mass of the nickel hydroxide which is present. In combination with aluminum hydroxide or aluminum oxide, the positive electrode further contains lanthanoid oxidic compounds Y.sub.2 O.sub.3, La.sub.2 O.sub.3 and Ca(OH).sub.2, as well as mixtures of these compounds.

  10. High capacity stabilized complex hydrides for hydrogen storage

    DOE Patents [OSTI]

    Zidan, Ragaiy; Mohtadi, Rana F; Fewox, Christopher; Sivasubramanian, Premkumar

    2014-11-11T23:59:59.000Z

    Complex hydrides based on Al(BH.sub.4).sub.3 are stabilized by the presence of one or more additional metal elements or organic adducts to provide high capacity hydrogen storage material.

  11. Metal Hydride Chemical Heat Pumps for Industrial Use 

    E-Print Network [OSTI]

    Ally, M. R.; Rebello, W. J.; Rosso, M. J., Jr.

    1984-01-01T23:59:59.000Z

    Hydriding alloys are intermetallic absorbent compounds which have the remarkable quality of absorbing very large quantities of hydrogen gas per unit volume of metallic powder. The absorption and desorption of hydrogen are exothermic and endothermic...

  12. Transient analysis of hydride fueled pressurized water reactor cores

    E-Print Network [OSTI]

    Trant, Jarrod Michael

    2004-01-01T23:59:59.000Z

    This thesis contributes to the hydride nuclear fuel project led by U. C. Berkeley for which MIT is to perform the thermal hydraulic and economic analyses. A parametric study has been performed to determine the optimum ...

  13. Metal Hydride Chemical Heat Pumps for Industrial Use

    E-Print Network [OSTI]

    Ally, M. R.; Rebello, W. J.; Rosso, M. J., Jr.

    1984-01-01T23:59:59.000Z

    Hydriding alloys are intermetallic absorbent compounds which have the remarkable quality of absorbing very large quantities of hydrogen gas per unit volume of metallic powder. The absorption and desorption of hydrogen are exothermic and endothermic...

  14. Advanced nickel-metal hydride cell development. Final report, September 1993--March 1996

    SciTech Connect (OSTI)

    Lim, Hong S.

    1996-03-01T23:59:59.000Z

    Inert gas atomization using metal hydride alloys for a Ni/MH{sub x}cell was studied. Atomization of the alloys was demonstrated on a small production scale up to batch size of several kg. Relative performance of the atomized and nonatomized alloys was investigated for the electrode material in a Ni/MH{sub x} cell. The study included effects of charge-discharge rates, temperature, and particle size on cell voltage (polarization) and specific capacity. Results show that the specific capacity of the present atomized alloys was apprecialy smaller than that of the nonatomized powder, especially for initial cycles. Full activation of the atomized alloys oftentook several hundreds of cycles. However, no appreciable difference in discharge rate capability was observed with R10 and R12 alloys. Chemical compositions were indistinguishable, although the oxygen contents of the atomized alloys were always higher. Effects of Ni and Cu coating on alloy performance were studied after electroless coating; the coatings noticeably improved the electrode rate capability for all the alloys. The electrode polarization was esecially improved, but not the cycle life. Further studies are needed.

  15. Optimization of Hydride Rim Formation in Unirradiated Zr 4 Cladding

    SciTech Connect (OSTI)

    Shimskey, Rick W.; Hanson, Brady D.; MacFarlan, Paul J.

    2013-09-30T23:59:59.000Z

    The purpose of this work is to build on the results reported in the M2 milestone M2FT 13PN0805051, document number FCRD-USED-2013-000151 (Hanson, 2013). In that work, it was demonstrated that unirradiated samples of zircaloy-4 cladding could be pre-hydrided at temperatures below 400°C in pure hydrogen gas and that the growth of hydrides on the surface could be controlled by changing the surface condition of the samples and form a desired hydride rim on the outside diameter of the cladding. The work performed at Pacific Northwest National Laboratory since the issuing of the M2 milestone has focused its efforts to optimize the formation of a hydride rim on available zircaloy-4 cladding samples by controlling temperature variation and gas flow control during pre-hydriding treatments. Surface conditioning of the outside surface was also examined as a variable. The results of test indicate that much of the variability in the hydride thickness is due to temperature variation occurring in the furnaces as well as how hydrogen gas flows across the sample surface. Efforts to examine other alloys, gas concentrations, and different surface conditioning plan to be pursed in the next FY as more cladding samples become available

  16. CRYSTALLOGRAPHIC PROPERTIES AND MECHANICAL BEHAVIOR OF TITANIUM HYDRIDE LAYERS GROWN ON TITANIUM IMPLANTS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    CRYSTALLOGRAPHIC PROPERTIES AND MECHANICAL BEHAVIOR OF TITANIUM HYDRIDE LAYERS GROWN ON TITANIUM, Switzerland Keywords: SLA treated titanium - bone-anchored dental implants - transmission and scanning electron microscopy - titanium hydride sub-surface layer - epitaxy Abstract Commercially pure titanium

  17. Synthesis and small molecule chemistry of the niobaziridine-hydride functional group

    E-Print Network [OSTI]

    Figueroa, Joshua S

    2005-01-01T23:59:59.000Z

    Chapter 1. Synthesis and Divergent Reactivity of the Niobaziridine-Hydride Functional Group The synthesis, characterization and reactivity of the niobaziridine-hydride complex Nb(H)([eta]²-t- ]Bu(H)C=NAr)(N[Np]Ar)? (la-H; ...

  18. Storage, generation, and use of hydrogen

    DOE Patents [OSTI]

    McClaine, Andrew W.; Rolfe, Jonathan L.; Larsen, Christopher A.; Konduri, Ravi K.

    2006-05-30T23:59:59.000Z

    A composition comprising a carrier liquid; a dispersant; and a chemical hydride. The composition can be used in a hydrogen generator to generate hydrogen for use, e.g., as a fuel. A regenerator recovers elemental metal from byproducts of the hydrogen generation process.

  19. THERMAL ENHANCEMENT CARTRIDGE HEATER MODIFIED TECH MOD TRITIUM HYDRIDE BED DEVELOPMENT PART I DESIGN AND FABRICATION

    SciTech Connect (OSTI)

    Klein, J.; Estochen, E.

    2014-03-06T23:59:59.000Z

    The Savannah River Site (SRS) tritium facilities have used 1{sup st} generation (Gen1) LaNi{sub 4.25}Al{sub 0.75} (LANA0.75) metal hydride storage beds for tritium absorption, storage, and desorption. The Gen1 design utilizes hot and cold nitrogen supplies to thermally cycle these beds. Second and 3{sup rd} generation (Gen2 and Gen3) storage bed designs include heat conducting foam and divider plates to spatially fix the hydride within the bed. For thermal cycling, the Gen2 and Gen 3 beds utilize internal electric heaters and glovebox atmosphere flow over the bed inside the bed external jacket for cooling. The currently installed Gen1 beds require replacement due to tritium aging effects on the LANA0.75 material, and cannot be replaced with Gen2 or Gen3 beds due to different designs of these beds. At the end of service life, Gen1 bed desorption efficiencies are limited by the upper temperature of hot nitrogen supply. To increase end-of-life desorption efficiency, the Gen1 bed design was modified, and a Thermal Enhancement Cartridge Heater Modified (TECH Mod) bed was developed. Internal electric cartridge heaters in the new design to improve end-of-life desorption, and also permit in-bed tritium accountability (IBA) calibration measurements to be made without the use of process tritium. Additional enhancements implemented into the TECH Mod design are also discussed.

  20. JOURNAL DE PHYSIQUE ColZoque C9, suppZe'ment au nO1l, Tome 41, novembre 1980, page C9-449 A POTENTIAL ATOMIC IODINE LASER PUMPED BY ELECTRICALLY GENERATED 'A OXYGEN

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -449 A POTENTIAL ATOMIC IODINE LASER PUMPED BY ELECTRICALLY GENERATED 'A OXYGEN G. Fournier, J. Bonnet and D ation. This paper shows that an electron generator of 1~ oxygen [21 . A condition beam controlled discharge could be an for lasing is a concentration ratio ['A] / efficient oxygen generator to lase with C3z

  1. Composite Materials for Hazard Mitigation of Reactive Metal Hydrides.

    SciTech Connect (OSTI)

    Pratt, Joseph William; Cordaro, Joseph Gabriel; Sartor, George B.; Dedrick, Daniel E.; Reeder, Craig L.

    2012-02-01T23:59:59.000Z

    In an attempt to mitigate the hazards associated with storing large quantities of reactive metal hydrides, polymer composite materials were synthesized and tested under simulated usage and accident conditions. The composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride. Composites with vinyl-containing siloxane oligomers were also polymerized with and without added styrene and divinyl benzene. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride reduced the inherent hydrogen storage capacity of the material. The composites were found to be initially effective at reducing the amount of heat released during oxidation. However, upon cycling the composites, the mitigating behavior was lost. While the polymer composites we investigated have mitigating potential and are physically robust, they undergo a chemical change upon cycling that makes them subsequently ineffective at mitigating heat release upon oxidation of the metal hydride. Acknowledgements The authors would like to thank the following people who participated in this project: Ned Stetson (U.S. Department of Energy) for sponsorship and support of the project. Ken Stewart (Sandia) for building the flow-through calorimeter and cycling test stations. Isidro Ruvalcaba, Jr. (Sandia) for qualitative experiments on the interaction of sodium alanate with water. Terry Johnson (Sandia) for sharing his expertise and knowledge of metal hydrides, and sodium alanate in particular. Marcina Moreno (Sandia) for programmatic assistance. John Khalil (United Technologies Research Corp) for insight into the hazards of reactive metal hydrides and real-world accident scenario experiments. Summary In an attempt to mitigate and/or manage hazards associated with storing bulk quantities of reactive metal hydrides, polymer composite materials (a mixture of a mitigating polymer and a metal hydride) were synthesized and tested under simulated usage and accident conditions. Mitigating the hazards associated with reactive metal hydrides during an accident while finding a way to keep the original capability of the active material intact during normal use has been the focus of this work. These composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride, in this case a prepared sodium alanate (chosen as a representative reactive metal hydride). It was found that the polymerization of styrene and divinyl benzene could be initiated using AIBN in toluene at 70 degC. The resulting composite materials can be either hard or brittle solids depending on the cross-linking density. Thermal decomposition of these styrene-based composite materials is lower than neat polystyrene indicating that the chemical nature of the polymer is affected by the formation of the composite. The char-forming nature of cross-linked polystyrene is low and therefore, not an ideal polymer for hazard mitigation. To obtain composite materials containing a polymer with higher char-forming potential, siloxane-based monomers were investigated. Four vinyl-containing siloxane oligomers were polymerized with and without added styrene and divinyl benzene. Like the styrene materials, these composite materials exhibited thermal decomposition behavior significantly different than the neat polymers. Specifically, the thermal decomposition temperature was shifted approximately 100 degC lower than the neat polymer signifying a major chemical change to the polymer network. Thermal analysis of the cycled samples was performed on the siloxane-based composite materials. It was found that after 30 cycles the siloxane-containing polymer composite material has similar TGA/DSC-MS traces as the virgin composite material indicating that the polymer is physically intact upon cycling. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride in the form of a composite material reduced the inherent hydrogen storage capacity of the material. This

  2. Models for Metal Hydride Particle Shape, Packing, and Heat Transfer

    E-Print Network [OSTI]

    Kyle C. Smith; Timothy S. Fisher

    2012-05-04T23:59:59.000Z

    A multiphysics modeling approach for heat conduction in metal hydride powders is presented, including particle shape distribution, size distribution, granular packing structure, and effective thermal conductivity. A statistical geometric model is presented that replicates features of particle size and shape distributions observed experimentally that result from cyclic hydride decreptitation. The quasi-static dense packing of a sample set of these particles is simulated via energy-based structural optimization methods. These particles jam (i.e., solidify) at a density (solid volume fraction) of 0.665+/-0.015 - higher than prior experimental estimates. Effective thermal conductivity of the jammed system is simulated and found to follow the behavior predicted by granular effective medium theory. Finally, a theory is presented that links the properties of bi-porous cohesive powders to the present systems based on recent experimental observations of jammed packings of fine powder. This theory produces quantitative experimental agreement with metal hydride powders of various compositions.

  3. High-Spin Cobalt Hydrides for Catalysis

    SciTech Connect (OSTI)

    Holland, Patrick L. [Yale University] [Yale University

    2013-08-29T23:59:59.000Z

    Organometallic chemists have traditionally used catalysts with strong-field ligands that give low-spin complexes. However, complexes with a weak ligand field have weaker bonds and lower barriers to geometric changes, suggesting that they may lead to more rapid catalytic reactions. Developing our understanding of high-spin complexes requires the use of a broader range of spectroscopic techniques, but has the promise of changing the mechanism and/or selectivity of known catalytic reactions. These changes may enable the more efficient utilization of chemical resources. A special advantage of cobalt and iron catalysts is that the metals are more abundant and cheaper than those currently used for major industrial processes that convert unsaturated organic molecules and biofeedstocks into useful chemicals. This project specifically evaluated the potential of high-spin cobalt complexes for small-molecule reactions for bond rearrangement and cleavage reactions relevant to hydrocarbon transformations. We have learned that many of these reactions proceed through crossing to different spin states: for example, high-spin complexes can flip one electron spin to access a lower-energy reaction pathway for beta-hydride elimination. This reaction enables new, selective olefin isomerization catalysis. The high-spin cobalt complexes also cleave the C-O bond of CO2 and the C-F bonds of fluoroarenes. In each case, the detailed mechanism of the reaction has been determined. Importantly, we have discovered that the cobalt catalysts described here give distinctive selectivities that are better than known catalysts. These selectivities come from a synergy between supporting ligand design and electronic control of the spin-state crossing in the reactions.

  4. Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields: An ab initio self-interaction-free time-dependent density-functional approach

    E-Print Network [OSTI]

    Carrera, Juan J.; Chu, Shih-I; Tong, Xiao-Min

    2005-06-21T23:59:59.000Z

    We present an ab initio nonpertubative investigation of the mechanisms responsible for the production of very-high-order harmonic generation (HHG) from Ar atoms and Ar+ ions by means of the self-interaction-free time-dependent density...

  5. Process of forming a sol-gel/metal hydride composite

    DOE Patents [OSTI]

    Congdon, James W. (Aiken, SC)

    2009-03-17T23:59:59.000Z

    An external gelation process is described which produces granules of metal hydride particles contained within a sol-gel matrix. The resulting granules are dimensionally stable and are useful for applications such as hydrogen separation and hydrogen purification. An additional coating technique for strengthening the granules is also provided.

  6. air metal hydride: Topics by E-print Network

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

    air metal hydride First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Carbon-Fluorine Bond Cleavage by...

  7. Dynamics of oxygen Rydberg atom generation following O 1s inner-shell excitation of H{sub 2}O

    SciTech Connect (OSTI)

    Gejo, T., E-mail: gejo@sci.u-hyogo.ac.jp; Ikegami, T.; Honma, K. [University of Hyogo, Koto 3-2-1, Kamigori-cho, Ako-gun, Hyogo 678-1297 (Japan); Takahashi, O. [Hiroshima University, 2-2 Kagamiyama 1-chome, Higashihiroshima 739-8512 (Japan); Shigemasa, E. [UVSOR Facility, Institute for Molecular Science, 38 Nishigo-Naka, Myodaiji, Okazaki 444-8585 (Japan); Hikosaka, Y. [Department of Environmental Science, Niigata University, 8050, Ikarashi 2-no-cho, Nishi-ku, Niigata 950-2181 (Japan); Tamenori, Y. [JASRI, Koto 1-1-1, Sayo-cho, Hyogo 679-5198 (Japan)

    2014-06-07T23:59:59.000Z

    The emission of low-energy electrons from H{sub 2}O has been investigated at photon excitation energies in the vicinity of the O 1s ionization threshold. Neutral oxygen Rydberg atoms (O*) were found to form, and the correlation between the initial inner-shell excited state of H{sub 2}O and the Rydberg state of O* was determined. The initially excited electron in a Rydberg orbital is shown to remain associated with O* even after the cleavage of two O-H bonds. We also show that the energy discrepancy between two Rydberg states of H{sub 2}O and O* can be explained by the influence of the post-collision interaction, which becomes stronger as the excitation energy approaches the 1s ionization threshold.

  8. FEASIBILITY OF RECYCLING PLUTONIUM AND MINOR ACTINIDES IN LIGHT WATER REACTORS USING HYDRIDE FUEL

    SciTech Connect (OSTI)

    Greenspan, Ehud; Todreas, Neil; Taiwo, Temitope

    2009-03-10T23:59:59.000Z

    The objective of this DOE NERI program sponsored project was to assess the feasibility of improving the plutonium (Pu) and minor actinide (MA) recycling capabilities of pressurized water reactors (PWRs) by using hydride instead of oxide fuels. There are four general parts to this assessment: 1) Identifying promising hydride fuel assembly designs for recycling Pu and MAs in PWRs 2) Performing a comprehensive systems analysis that compares the fuel cycle characteristics of Pu and MA recycling in PWRs using the promising hydride fuel assembly designs identified in Part 1 versus using oxide fuel assembly designs 3) Conducting a safety analysis to assess the likelihood of licensing hydride fuel assembly designs 4) Assessing the compatibility of hydride fuel with cladding materials and water under typical PWR operating conditions Hydride fuel was found to offer promising transmutation characteristics and is recommended for further examination as a possible preferred option for recycling plutonium in PWRs.

  9. ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE

    SciTech Connect (OSTI)

    Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J

    2009-01-09T23:59:59.000Z

    One of the challenges of implementing the hydrogen economy is finding a suitable solid H{sub 2} storage material. Aluminium (alane, AlH{sub 3}) hydride has been examined as a potential hydrogen storage material because of its high weight capacity, low discharge temperature, and volumetric density. Recycling the dehydride material has however precluded AlH{sub 3} from being implemented due to the large pressures required (>10{sup 5} bar H{sub 2} at 25 C) and the thermodynamic expense of chemical synthesis. A reversible cycle to form alane electrochemically using NaAlH{sub 4} in THF been successfully demonstrated. Alane is isolated as the triethylamine (TEA) adduct and converted to unsolvated alane by heating under vacuum. To complete the cycle, the starting alanate can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride (NaH) This novel reversible cycle opens the door for alane to fuel the hydrogen economy.

  10. Ground-state energy and relativistic corrections for positronium hydride

    SciTech Connect (OSTI)

    Bubin, Sergiy; Varga, Kalman [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)

    2011-07-15T23:59:59.000Z

    Variational calculations of the ground state of positronium hydride (HPs) are reported, including various expectation values, electron-positron annihilation rates, and leading relativistic corrections to the total and dissociation energies. The calculations have been performed using a basis set of 4000 thoroughly optimized explicitly correlated Gaussian basis functions. The relative accuracy of the variational energy upper bound is estimated to be of the order of 2x10{sup -10}, which is a significant improvement over previous nonrelativistic results.

  11. Thermomechanics of hydrogen storage in metallic hydrides: modeling and analysis

    E-Print Network [OSTI]

    Tomas Roubicek; Giuseppe Tomassetti

    2013-09-12T23:59:59.000Z

    A thermodynamically consistent mathematical model for hydrogen adsorption in metal hydrides is proposed. Beside hydrogen diffusion, the model accounts for phase transformation accompanied by hysteresis, swelling, temperature and heat transfer, strain, and stress. We prove existence of solutions of the ensuing system of partial differential equations by a carefully-designed, semi-implicit approximation scheme. A generalization for a drift-diffusion of multi-component ionized "gas" is outlined, too.

  12. The affect of erbium hydride on the conversion efficience to accelerated protons from ultra-shsort pulse laser irradiated foils

    SciTech Connect (OSTI)

    Offermann, D

    2008-09-04T23:59:59.000Z

    This thesis work explores, experimentally, the potential gains in the conversion efficiency from ultra-intense laser light to proton beams using erbium hydride coatings. For years, it has been known that contaminants at the rear surface of an ultra-intense laser irradiated thin foil will be accelerated to multi-MeV. Inertial Confinement Fusion fast ignition using proton beams as the igniter source requires of about 10{sup 16} protons with an average energy of about 3MeV. This is far more than the 10{sup 12} protons available in the contaminant layer. Target designs must include some form of a hydrogen rich coating that can be made thick enough to support the beam requirements of fast ignition. Work with computer simulations of thin foils suggest the atomic mass of the non-hydrogen atoms in the surface layer has a strong affect on the conversion efficiency to protons. For example, the 167amu erbium atoms will take less energy away from the proton beam than a coating using carbon with a mass of 12amu. A pure hydrogen coating would be ideal, but technologically is not feasible at this time. In the experiments performed for my thesis, ErH{sub 3} coatings on 5 {micro}m gold foils are compared with typical contaminants which are approximately equivalent to CH{sub 1.7}. It will be shown that there was a factor of 1.25 {+-} 0.19 improvement in the conversion efficiency for protons above 3MeV using erbium hydride using the Callisto laser. Callisto is a 10J per pulse, 800nm wavelength laser with a pulse duration of 200fs and can be focused to a peak intensity of about 5 x 10{sup 19}W/cm{sup 2}. The total number of protons from either target type was on the order of 10{sup 10}. Furthermore, the same experiment was performed on the Titan laser, which has a 500fs pulse duration, 150J of energy and can be focused to about 3 x 10{sup 20} W/cm{sup 2}. In this experiment 10{sup 12} protons were seen from both erbium hydride and contaminants on 14 {micro} m gold foils. Significant improvements were also observed but possibly because of the depletion of hydrogen in the contaminant layer case.

  13. Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices

    DOE Patents [OSTI]

    Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R

    2014-11-18T23:59:59.000Z

    An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles.

  14. Hydrogen storage material and process using graphite additive with metal-doped complex hydrides

    DOE Patents [OSTI]

    Zidan, Ragaiy (Aiken, SC); Ritter, James A. (Lexington, SC); Ebner, Armin D. (Lexington, SC); Wang, Jun (Columbia, SC); Holland, Charles E. (Cayce, SC)

    2008-06-10T23:59:59.000Z

    A hydrogen storage material having improved hydrogen absorbtion and desorption kinetics is provided by adding graphite to a complex hydride such as a metal-doped alanate, i.e., NaAlH.sub.4. The incorporation of graphite into the complex hydride significantly enhances the rate of hydrogen absorbtion and desorption and lowers the desorption temperature needed to release stored hydrogen.

  15. Solid-State Gadolinium-Magnesium Hydride Optical Switch R. Armitage

    E-Print Network [OSTI]

    -state electrochromic device. With positive polarization of the hydride electrode, the visible reflectance approaches 35 and reflecting states. Keywords: gadolinium-magnesium; electrochromic hydride; optical switching device. 2 #12;A conventional electrochromics5 . Optical switching has also been demonstrated by varying the H content

  16. X-ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films

    E-Print Network [OSTI]

    X-ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films T. J. Richardsona@lbl.gov Abstract Mixed metal thin films containing magnesium and a first-row transition element exhibit very large of magnesium hydride. Keywords: A. hydrogen storage materials, thin films; C. EXAFS, NEXAFS, X-ray diffraction

  17. Multiphoton ionization and high-order harmonic generation of He, Ne, and Ar atoms in intense pulsed laser fields: Self-interaction-free time-dependent density-functional theoretical approach

    E-Print Network [OSTI]

    Chu, Shih-I; Tong, Xiao-Min

    2001-06-12T23:59:59.000Z

    We present a detailed study of the multiphoton ionization and high-order harmonic generation (HHG) processes of rare-gas atoms (He, Ne, and Ar) in intense pulsed laser fields by means of a self-interaction-free time-dependent density...

  18. Elastic modulus mapping of atomically thin film based Lithium Ion Battery electrodes Lithium Ion Batteries (LIB) are one of the most promising class of next generation energy storage devices,

    E-Print Network [OSTI]

    Batteries (LIB) are one of the most promising class of next generation energy storage devices, which canElastic modulus mapping of atomically thin film based Lithium Ion Battery electrodes Lithium Ion the charging/discharging which otherwise lead to in efficient battery operation. The cyclically charging

  19. Mathematical modeling of the nickel/metal hydride battery system

    SciTech Connect (OSTI)

    Paxton, B K [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering

    1995-09-01T23:59:59.000Z

    A group of compounds referred to as metal hydrides, when used as electrode materials, is a less toxic alternative to the cadmium hydroxide electrode found in nickel/cadmium secondary battery systems. For this and other reasons, the nickel/metal hydride battery system is becoming a popular rechargeable battery for electric vehicle and consumer electronics applications. A model of this battery system is presented. Specifically the metal hydride material, LaNi{sub 5}H{sub 6}, is chosen for investigation due to the wealth of information available in the literature on this compound. The model results are compared to experiments found in the literature. Fundamental analyses as well as engineering optimizations are performed from the results of the battery model. In order to examine diffusion limitations in the nickel oxide electrode, a ``pseudo 2-D model`` is developed. This model allows for the theoretical examination of the effects of a diffusion coefficient that is a function of the state of charge of the active material. It is found using present data from the literature that diffusion in the solid phase is usually not an important limitation in the nickel oxide electrode. This finding is contrary to the conclusions reached by other authors. Although diffusion in the nickel oxide active material is treated rigorously with the pseudo 2-D model, a general methodology is presented for determining the best constant diffusion coefficient to use in a standard one-dimensional battery model. The diffusion coefficients determined by this method are shown to be able to partially capture the behavior that results from a diffusion coefficient that varies with the state of charge of the active material.

  20. ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE

    SciTech Connect (OSTI)

    Fewox, C; Ragaiy Zidan, R; Brenda Garcia-Diaz, B

    2008-12-31T23:59:59.000Z

    Hydrogen storage is one of the greatest challenges for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods; the direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum.

  1. ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE

    SciTech Connect (OSTI)

    Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J

    2009-01-09T23:59:59.000Z

    Hydrogen storage is one of the challenges to be overcome for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods. The direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali metal alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum.

  2. Proximity breakdown of hydrides in superconducting niobium cavities

    E-Print Network [OSTI]

    Romanenko, A; Cooley, L D; Grassellino, A

    2012-01-01T23:59:59.000Z

    Many modern and proposed future particle accelerators rely on superconducting radio frequency cavities made of bulk niobium as primary particle accelerating structures. Such cavities suffer from the anomalous field dependence of their quality factors Q0. High field degradation - so-called high field Q-slope - is yet unexplained even though an empirical cure is known. Here we propose a mechanism based on the presence of proximity-coupled niobium hydrides, which can explain this effect. Furthermore, the same mechanism can be present in any surface-sensitive experiments or superconducting devices involving niobium.

  3. Working with SRNL - Our Facilities - Metal Hydride Laboratories

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhat is abigpresentedMetal Hydride Laboratories

  4. Comparative analysis of the high-order harmonic generation in the laser ablation plasmas prepared on the surfaces of complex and atomic targets

    SciTech Connect (OSTI)

    Ganeev, R. A. [Scientific Association Akadempribor, Academy of Sciences of Uzbekistan, Akademgorodok, Tashkent 100125 (Uzbekistan); Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Milosevic, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany)

    2008-07-15T23:59:59.000Z

    We analyzed high-order harmonic generation from the plasma plumes prepared on the surfaces of complex targets. The studies of In-Ag targets showed that the characteristics of the high-order harmonics from the double-target plume were the same as those from the single-target plasmas. For the chromium-tellurium plasma, the enhancements of the 29th and 27th harmonics were obtained, thus indicating the appearance of the enhancement properties from both components of the double-target plasma. These comparative studies also showed higher enhancement of a single harmonic in the case of atomic plasma (Sb) with regard to the molecular one (InSb). The additional component can only decrease the enhancement factor of the medium, due to the change of the oscillator strength and spectral distribution of the transitions involved in the resonance enhancement of the specific harmonic order. The theoretical calculations have shown the enhancement of specific harmonics for the Sb, Te, and Cr plasmas in the double-target configurations.

  5. Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems

    SciTech Connect (OSTI)

    Peterman, D.J.

    1980-01-01T23:59:59.000Z

    Electronic band structure calculations are used to interpret the optical spectra of the cubic Sc, Y and La hydride systems. Self-consistent band calculations of ScH/sub 2/ and YH/sub 2/ were carried out. The respective joint densities of states are computed and compared to the dielectric functions determined from the optical measurements. Additional calculations were performed in which the Fermi level or band gap energies are rigidly shifted by a small energy increment. These calculations are then used to simulate the derivative structure in thermomodulation spectra and relate the origin of experimental interband features to the calculated energy bands. While good systematic agreement is obtained for several spectral features, the origin of low-energy interband transitions in YH/sub 2/ cannot be explained by these calculated bands. A lattice-size-dependent premature occupation of octahedral sites by hydrogen atoms in the fcc metal lattice is suggested to account for this discrepancy. Various non-self-consistent calculations are used to examine the effect of such a premature occupation. Measurements of the optical absorptivity of LaH/sub x/ with 1.6 < x < 2.9 are presented which, as expected, indicate a more premature occupation of the octahedral sites in the larger LaH/sub 2/ lattice. These experimental results also suggest that, in contrast to recent calculations, LaH/sub 3/ is a small-band-gap semiconductor.

  6. ACCEPTABILITY ENVELOPE FOR METAL HYDRIDE-BASED HYDROGEN STORAGE SYSTEMS

    SciTech Connect (OSTI)

    Hardy, B.; Corgnale, C.; Tamburello, D.; Garrison, S.; Anton, D.

    2011-07-18T23:59:59.000Z

    The design and evaluation of media based hydrogen storage systems requires the use of detailed numerical models and experimental studies, with significant amount of time and monetary investment. Thus a scoping tool, referred to as the Acceptability Envelope, was developed to screen preliminary candidate media and storage vessel designs, identifying the range of chemical, physical and geometrical parameters for the coupled media and storage vessel system that allow it to meet performance targets. The model which underpins the analysis allows simplifying the storage system, thus resulting in one input-one output scheme, by grouping of selected quantities. Two cases have been analyzed and results are presented here. In the first application the DOE technical targets (Year 2010, Year 2015 and Ultimate) are used to determine the range of parameters required for the metal hydride media and storage vessel. In the second case the most promising metal hydrides available are compared, highlighting the potential of storage systems, utilizing them, to achieve 40% of the 2010 DOE technical target. Results show that systems based on Li-Mg media have the best potential to attain these performance targets.

  7. GAS-PHASE REACTIONS OF HYDRIDE ANION, H{sup -}

    SciTech Connect (OSTI)

    Martinez, Oscar; Yang Zhibo; Demarais, Nicholas J.; Bierbaum, Veronica M. [Department of Chemistry and Biochemistry, 215 UCB, University of Colorado, Boulder, CO 80309-0215 (United States); Snow, Theodore P., E-mail: Oscar.Martinez@colorado.ed, E-mail: Zhibo.Yang@colorado.ed, E-mail: Nicholas.Demarais@colorado.ed, E-mail: Veronica.Bierbaum@colorado.ed, E-mail: Theodore.Snow@colorado.ed [Department of Astrophysical and Planetary Sciences, 391 UCB, University of Colorado, Boulder, CO 80309-0391 (United States)

    2010-09-01T23:59:59.000Z

    Rate constants were measured at 300 K for the reactions of the hydride anion, H{sup -}, with neutral molecules C{sub 2}H{sub 2}, H{sub 2}O, CH{sub 3}CN, CH{sub 3}OH, (CH{sub 3}){sub 2}CO, CH{sub 3}CHO, N{sub 2}O, CO{sub 2}, O{sub 2}, CO, CH{sub 3}Cl, (CH{sub 3}){sub 3}CCl, (CH{sub 3}CH{sub 2}){sub 2}O, C{sub 6}H{sub 6}, and D{sub 2} using a flowing-afterglow instrument. Experimental work was supplemented by ab initio calculations to provide insight into the viability of reaction pathways. Our reported rate constants should prove useful to models of astrophysical environments where conditions prevail for the existence of both H{sup -} and neutral species. The variety of neutral reactants studied includes representative species from prototypical chemical groups, effectively mapping reactivity trends for the hydride anion.

  8. Microstructure and hydriding studies of AB/sub 5/ hydrogen storage compounds. Final report

    SciTech Connect (OSTI)

    Goodell, P.D.; Sandrock, G.D.; Huston, E.L.

    1980-01-01T23:59:59.000Z

    New data on the microstructure, pressure-composition-temperature, and absorption/desorption kinetics of AB/sub 5/ metal hydrides are presented. The most significant result to emerge from the investigation is that many of the AB/sub 5/ metal hydrides, especially the LaNi/sub 5/ related materials, show instantaneous absorption and desorption response in proportion to the amount of cooling or heating which is provided. Eight categories of materials were studied: reference alloys (LaNi/sub 5/, LaNi/sub 4/ /sub 9/Al/sub 0/ /sub 1/, LaNi/sub 3/Co/sub 2/); Ni second phase particles (LaNi/sub 5/ /sub 67/, LaNi/sub 7/, LaNi/sub 11/ /sub 3/); eutectoid microstructure (SmCo/sub 5/); other second phases (LaNi/sub 3/ /sub 8/Fe/sub 1/ /sub 2/, LaNi/sub 3/ /sub 5/Cr/sub 1/ /sub 5/, LaNi/sub 4/Cr, LaNi/sub 4/Si; LaNi/sub 4/Sn, MNi/sub 4/Sn, MNi/sub 4/ /sub 3/Al/sub 0/ /sub 7/); substitutional elements (LaNi/sub 4/Cu, LaNi/sub 4/ /sub 5/Pd/sub 0/ /sub 5/, LaNi/sub 4/ /sub 7/Sn/sub 0/ /sub 3/, LaNi/sub 4/ /sub 8/C/sub 0/ /sub 2/, MNi/sub 4/ /sub 3/Mn/sub 0/ /sub 7/); surface active elements (LaNi/sub 4/ /sub 8/B/sub 0/ /sub 2/, LaNi/sub 4/ /sub 9/S/sub 0/ /sub 1/, LaNi/sub 4/ /sub 9/Se/sub 0/ /sub 1/); large diameter atom substitutions (Mg/sub 0/ /sub 1/La/sub 0/ /sub 9/Ni/sub 5/, Ca/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/, Sr/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/, Ba/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/); other compositions (LaNi/sub 3/); and Pd plating (electroless plated samples and mechanically alloyed specimens).

  9. Calibration of a single atom detector for atomic micro chips

    E-Print Network [OSTI]

    A. Stibor; S. Kraft; T. Campey; D. Komma; A. Günther; J. Fortágh; C. J. Vale; H. Rubinsztein-Dunlop; C. Zimmermann

    2007-02-13T23:59:59.000Z

    We experimentally investigate a scheme for detecting single atoms magnetically trapped on an atom chip. The detector is based on the photoionization of atoms and the subsequent detection of the generated ions. We describe the characterization of the ion detector with emphasis on its calibration via the correlation of ions with simultaneously generated electrons. A detection efficiency of 47.8% (+-2.6%) is measured, which is useful for single atom detection, and close to the limit allowing atom counting with sub-Poissonian uncertainty.

  10. Final report for the DOE Metal Hydride Center of Excellence.

    SciTech Connect (OSTI)

    Keller, Jay O.; Klebanoff, Leonard E.

    2012-01-01T23:59:59.000Z

    This report summarizes the R&D activities within the U.S. Department of Energy Metal Hydride Center of Excellence (MHCoE) from March 2005 to June 2010. The purpose of the MHCoE has been to conduct highly collaborative and multi-disciplinary applied R&D to develop new reversible hydrogen storage materials that meet or exceed DOE 2010 and 2015 system goals for hydrogen storage materials. The MHCoE combines three broad areas: mechanisms and modeling (which provide a theoretically driven basis for pursuing new materials), materials development (in which new materials are synthesized and characterized) and system design and engineering (which allow these new materials to be realized as practical automotive hydrogen storage systems). This Final Report summarizes the organization and execution of the 5-year research program to develop practical hydrogen storage materials for light duty vehicles. Major results from the MHCoE are summarized, along with suggestions for future research areas.

  11. Atomic magnetometer

    DOE Patents [OSTI]

    Schwindt, Peter (Albuquerque, NM); Johnson, Cort N. (Albuquerque, NM)

    2012-07-03T23:59:59.000Z

    An atomic magnetometer is disclosed which uses a pump light beam at a D1 or D2 transition of an alkali metal vapor to magnetically polarize the vapor in a heated cell, and a probe light beam at a different D2 or D1 transition to sense the magnetic field via a polarization rotation of the probe light beam. The pump and probe light beams are both directed along substantially the same optical path through an optical waveplate and through the heated cell to an optical filter which blocks the pump light beam while transmitting the probe light beam to one or more photodetectors which generate electrical signals to sense the magnetic field. The optical waveplate functions as a quarter waveplate to circularly polarize the pump light beam, and as a half waveplate to maintain the probe light beam linearly polarized.

  12. Photogeneration of Hydride Donors and Their Use Toward CO2 Reduction

    SciTech Connect (OSTI)

    Fujita,E.; Muckerman, J.T.; Polyansky, D.E.

    2009-06-07T23:59:59.000Z

    Despite substantial effort, no one has succeeded in efficiently producing methanol from CO2 using homogeneous photocatalytic systems. We are pursuing reaction schemes based on a sequence of hydride-ion transfers to carry out stepwise reduction of CO2 to methanol. We are using hydride-ion transfer from photoproduced C-H bonds in metal complexes with bio-inspired ligands (i.e., NADH-like ligands) that are known to store one proton and two electrons.

  13. The effects of phosphorous donor ligand substitution on the reactivity of anionic group 6 transition metal carbonyl hydrides

    E-Print Network [OSTI]

    Lusk, Richard Jay

    1986-01-01T23:59:59.000Z

    in THP, followed by protonation with methanol, gave rise to a new group of chromium and tungsten hydrides, 7 HM(CO) P . The importance of the P-substituted hydr ides is enhanced 4 reactivity as well as the possibility of selective hydride transfer... found to be similar to those of the unsubstituted tungsten hydride. Reaction of this phosphite hydride with HC1, HOAc 7 (acetic acid), or phenol results in formation of W(CO)&(OAc)P(OMe) W(CO)&P(OMe) Cl , and (u-H)W (CO)S(P(OMe) ) , respectively...

  14. ALKYL, HYDRIDE, AND RELATED BIS (TRIMETHYLSILYL)-AMIDE DERIVATIVES OF THE 4f- AND 5f- BLOCK METALS

    E-Print Network [OSTI]

    Andersen, R.A.

    2010-01-01T23:59:59.000Z

    shifts to 1060 c m in the deuteride. The paramagnetic (u -The first step is hydride for deuteride exchange by way of a

  15. Documentation of Hybrid Hydride Model for Incorporation into Moose-Bison and Validation Strategy.

    SciTech Connect (OSTI)

    Weck, Philippe F; Tikare, Veena; Schultz, Peter Andrew; Clark, B (SNL); Mitchell, J (SNL); Glazoff, Michael V.; Homer, Eric R.

    2014-10-01T23:59:59.000Z

    This report documents the development, demonstration and validation of a mesoscale, microstructural evolution model for simulation of zirconium hydride ?-ZrH{sub 1.5} precipitation in the cladding of used nuclear fuels that may occur during long-term dry storage. While the Zr-based claddings are manufactured free of any hydrogen, they absorb hydrogen during service, in the reactor by a process commonly termed ‘hydrogen pick-up’. The precipitation and growth of zirconium hydrides during dry storage is one of the most likely fuel rod integrity failure mechanisms either by embrittlement or delayed hydride cracking of the cladding (Hanson et al., 2011). While the phenomenon is well documented and identified as a potential key failure mechanism during long-term dry storage (Birk et al., 2012 and NUREG/CR-7116), the ability to actually predict the formation of hydrides is poor. The model being documented in this work is a computational capability for the prediction of hydride formation in different claddings of used nuclear fuels. This work supports the Used Fuel Disposition Research and Development Campaign in assessing the structural engineering performance of the cladding during and after long-term dry storage. In this work, a model to numerically simulate hydride precipitation at the microstructural scale, in a wide variety of Zr-based claddings, under dry-storage conditions is being developed. It will be used to aid in the evaluation of the mechanical integrity of used fuel rods during dry storage and transportation by providing the structural conditions from the microstructural scale to the continuum scale to engineering component scale models to predict if the used fuel rods will perform without failure under normal and off-normal conditions. The microstructure, especially, the hydride structure is thought to be a primary determinant of cladding failure, thus this component of UFD’s storage and transportation analysis program is critical. The model development, application and validation of the model are documented and the limitations of the current model are discussed. The model has been shown to simulate hydride precipitation in Zircaloy-4 cladding with correct morphology, thermodynamics and kinetics. An unexpected insight obtained from simulations hydride formation in Zircaloy-4 is that small (sub-micron) precipitates need to order themselves to form the larger hydrides typically described as radially-reoriented precipitates. A limitation of this model is that it does not currently solve the stress state that forms dynamically in the precipitate or matrix surrounding the precipitate. A method to overcome the limitations is suggested and described in detail. The necessary experiments to provide key materials physics and to validate the model are also recommended.

  16. Characterization of the molecular structure and mechanical properties of polymer surfaces and protein/polymer interfaces by sum frequency generation vibrational spectroscopy and atomic force microscopy

    SciTech Connect (OSTI)

    Koffas, Telly Stelianos

    2004-05-15T23:59:59.000Z

    Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and other complementary surface-sensitive techniques have been used to study the surface molecular structure and surface mechanical behavior of biologically-relevant polymer systems. SFG and AFM have emerged as powerful analytical tools to deduce structure/property relationships, in situ, for polymers at air, liquid and solid interfaces. The experiments described in this dissertation have been performed to understand how polymer surface properties are linked to polymer bulk composition, substrate hydrophobicity, changes in the ambient environment (e.g., humidity and temperature), or the adsorption of macromolecules. The correlation of spectroscopic and mechanical data by SFG and AFM can become a powerful methodology to study and engineer materials with tailored surface properties. The overarching theme of this research is the interrogation of systems of increasing structural complexity, which allows us to extend conclusions made on simpler model systems. We begin by systematically describing the surface molecular composition and mechanical properties of polymers, copolymers, and blends having simple linear architectures. Subsequent chapters focus on networked hydrogel materials used as soft contact lenses and the adsorption of protein and surfactant at the polymer/liquid interface. The power of SFG is immediately demonstrated in experiments which identify the chemical parameters that influence the molecular composition and ordering of a polymer chain's side groups at the polymer/air and polymer/liquid interfaces. In general, side groups with increasingly greater hydrophobic character will be more surface active in air. Larger side groups impose steric restrictions, thus they will tend to be more randomly ordered than smaller hydrophobic groups. If exposed to a hydrophilic environment, such as water, the polymer chain will attempt to orient more of its hydrophilic groups to the surface in order to minimize the total surface energy. With an understanding of the structural and environmental parameters which govern polymer surface structure, SFG is then used to explore the effects of surface hydrophobicity and solvent polarity on the orientation and ordering of amphiphilic neutral polymers adsorbed at the solid/liquid interface. SFG spectra show that poly(propylene glycol) (PPG) and poly(ethylene glycol) (PEG) adsorb with their hydrophobic moieties preferentially oriented toward hydrophobic polystyrene surfaces. These same moieties, however, disorder when adsorbed onto a hydrophilic silica/water interface. Water is identified as a critical factor for mediating the orientation and ordering of hydrophobic moieties in polymers adsorbed at hydrophobic interfaces. The role of bulk water content and water vapor, as they influence hydrogel surface structure and mechanics, continues to be explored in the next series of experiments. A method was developed to probe the surface viscoelastic properties of hydroxylethyl methacrylate (HEMA) based contact lens materials by analyzing AFM force-distance curves. AFM analysis indicates that the interfacial region is dehydrated, relative to the bulk. Experiments performed on poly(HEMA+MA) (MA = methacrylic acid), a more hydrophilic copolymer with greater bulk water content, show even greater water depletion at the surface. SFG spectra, as well as surface energy arguments, suggest that the more hydrophilic polymer component (such as MA) is not favored at the air interface; this may explain anomalies in water retention at the hydrogel surface. Adsorption of lysozyme onto poly(HEMA+MA) was found to further reduce near-surface viscous behavior, suggesting lower surface water content. Lastly, protein adsorption is studied using a model polymer system of polystyrene covalently bound with a monolayer of bovine serum albumin. SFG results indicate that some amino acid residues in proteins adopt preferred orientations. SFG spectra also show that the phenyl rings of the bare polystyrene substrate in contact with air or

  17. Materials Down-selection Decisions Made within the DOE Metal Hydride Center of Excellence (MHCoE) - September-October 2007

    Fuel Cell Technologies Publication and Product Library (EERE)

    Reports on which hydrogen storage materials offer potential for further research as decided by DOE's Metal Hydride Center of Excellence.

  18. Incorporation of Hydride Nuclear Fuels in Commercial Light Water Reactors

    E-Print Network [OSTI]

    Terrani, Kurt Amir

    2010-01-01T23:59:59.000Z

    electricity generation capacity and operating efficiency of nuclear plants [Nuclear Plant Capacity Factor Nuclear Electricity Generationelectricity generation capacity and operating efficiency of nu- clear plants [

  19. Raman Spectroscopy as a Probe of Surface Oxides and Hydrides on Niobium

    SciTech Connect (OSTI)

    J. Zasadzinski, B. Albee, S. Bishnoi, C. Cao, G. Ciovati, L.D. Cooley, D.C. Ford, Th. Proslier

    2011-07-01T23:59:59.000Z

    Raman microscopy/spectroscopy has been used in conjunction with AFM, tunneling and magnetic susceptibility to identify surface oxides and hydrides on annealed, recrystallized foils of high purity Nb and on single crystals of cavity grade Nb. Cold worked regions of the Nb foil as well as rough regions near grain boundaries showed clear evidence of ordered hydride phases which were identified by VASP phonon calculations. Cold worked regions also displayed enhanced surface paramagnetism. Surface enhanced Raman spectra have also been obtained using 1.0 nm Au depositon. The SERS spectra reveal hydride molecular species which are not observable by conventional Raman. These results indicate that Raman is a useful probe of Nb surfaces relevant for cavity performance

  20. High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides

    SciTech Connect (OSTI)

    Daniel A. Mosher; Xia Tang; Ronald J. Brown; Sarah Arsenault; Salvatore Saitta; Bruce L. Laube; Robert H. Dold; Donald L. Anton

    2007-07-27T23:59:59.000Z

    This final report describes the motivations, activities and results of the hydrogen storage independent project "High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides" performed by the United Technologies Research Center under the Department of Energy Hydrogen Program, contract # DE-FC36-02AL67610. The objectives of the project were to identify and address the key systems technologies associated with applying complex hydride materials, particularly ones which differ from those for conventional metal hydride based storage. This involved the design, fabrication and testing of two prototype systems based on the hydrogen storage material NaAlH4. Safety testing, catalysis studies, heat exchanger optimization, reaction kinetics modeling, thermochemical finite element analysis, powder densification development and material neutralization were elements included in the effort.

  1. Titanium tritide radioisotope heat source development : palladium-coated titanium hydriding kinetics and tritium loading tests.

    SciTech Connect (OSTI)

    Van Blarigan, Peter; Shugard, Andrew D.; Walters, R. Tom (Savannah River National Labs, Aiken, SC)

    2012-01-01T23:59:59.000Z

    We have found that a 180 nm palladium coating enables titanium to be loaded with hydrogen isotopes without the typical 400-500 C vacuum activation step. The hydriding kinetics of Pd coated Ti can be described by the Mintz-Bloch adherent film model, where the rate of hydrogen absorption is controlled by diffusion through an adherent metal-hydride layer. Hydriding rate constants of Pd coated and vacuum activated Ti were found to be very similar. In addition, deuterium/tritium loading experiments were done on stacks of Pd coated Ti foil in a representative-size radioisotope heat source vessel. The experiments demonstrated that such a vessel could be loaded completely, at temperatures below 300 C, in less than 10 hours, using existing department-of-energy tritium handling infrastructure.

  2. Process for production of an aluminum hydride compound

    DOE Patents [OSTI]

    Allen, Nathan Tait; Butterick, III, Robert; Chin, Arthur Achhing; Miller, Dean Michael; Molzahn, David Craig

    2013-08-06T23:59:59.000Z

    A compound of formula M(AlH.sub.3OR.sup.1).sub.y, wherein R.sup.1 is phenyl substituted by at least one of: (i) an alkoxy group having from one to six carbon atoms; and (ii) an alkyl group having from three to twelve carbon atoms; wherein M is an alkali metal, Be or Mg; and y is one or two.

  3. Method and composition in which metal hydride particles are embedded in a silica network

    DOE Patents [OSTI]

    Heung, Leung K. (Aiken, SC)

    1999-01-01T23:59:59.000Z

    A silica embedded metal hydride composition and a method for making such a composition. The composition is made via the following process: A quantity of fumed silica is blended with water to make a paste. After adding metal hydride particles, the paste is dried to form a solid. According to one embodiment of the invention, the solid is ground into granules for use of the product in hydrogen storage. Alternatively, the paste can be molded into plates or cylinders and then dried for use of the product as a hydrogen filter. Where mechanical strength is required, the paste can be impregnated in a porous substrate or wire network.

  4. A mechanistic study of aryl halide reactions with lithium aluminum hydride 

    E-Print Network [OSTI]

    Chung, Fu-Fan

    1980-01-01T23:59:59.000Z

    A M:"CHA~JISTIC STUDv OF ARYL HALID RHAC IC~JS ' ITH LITHIUM ALUM 'J"M HYDRIDE A Thesis FU-FAJJ CHUI'JG Submitted to the Graduate College of Texas ARM University in nartial fulfillment of the reauirement for the degree of MASTER OF SCI- JC... August Jo80 Major Subject: Chemistry A MECHANISTIC STUDY OF ARYL HALIDE REACTIONS 1'IITH LITHIUM ALUMINUM HYDRIDE A Thesis by FU-FAN CHUNG Approved as to style and content by; (Chairman of Co ittee) (Member) , . 7 1 (Member) (Member) i (Head...

  5. A mechanistic study of aryl halide reactions with lithium aluminum hydride

    E-Print Network [OSTI]

    Chung, Fu-Fan

    1980-01-01T23:59:59.000Z

    A M:"CHA~JISTIC STUDv OF ARYL HALID RHAC IC~JS ' ITH LITHIUM ALUM 'J"M HYDRIDE A Thesis FU-FAJJ CHUI'JG Submitted to the Graduate College of Texas ARM University in nartial fulfillment of the reauirement for the degree of MASTER OF SCI- JC... of this stud!y :a to investigate possibility o f a. fr ee r a . 1 ca machina=--. by;;h:ch ". thium alum'num hydride may reduce organic ccmnounds. evzcus results have irdicated that thc reductior of o-allylcxy- 'oenzene diazonium icn by . ributyltin hydrioe...

  6. The Use of Metal Hydrides for Hydrogen Recovery from Industrial Off-Gas Streams 

    E-Print Network [OSTI]

    Rebello, W. J.; Guerrero, P. S.; Goodell, P. D.

    1987-01-01T23:59:59.000Z

    . and with allo s based on certain intermetall c compounds. Lanthanium penta-nicke , LaNis, is one of the earliest sUfh compounds to be widely studied, and others will be discussed shortIt. Its reaction with hydrogen can e represented by: LaNis + 3H2 = La... Hydride Alloy TYPBS OF HYDRIDIHG ALLOYS Outside of a few elemental metals (Pd, V, Hb and Mg) most hydride formers that are reversible under conditions of practicai interest are based on intermetallic compounds. These usually consist of a strong...

  7. Method of production of pure hydrogen near room temperature from aluminum-based hydride materials

    DOE Patents [OSTI]

    Pecharsky, Vitalij K.; Balema, Viktor P.

    2004-08-10T23:59:59.000Z

    The present invention provides a cost-effective method of producing pure hydrogen gas from hydride-based solid materials. The hydride-based solid material is mechanically processed in the presence of a catalyst to obtain pure gaseous hydrogen. Unlike previous methods, hydrogen may be obtained from the solid material without heating, and without the addition of a solvent during processing. The described method of hydrogen production is useful for energy conversion and production technologies that consume pure gaseous hydrogen as a fuel.

  8. New binding materials for metal hydride electrodes which permit good recyclability

    SciTech Connect (OSTI)

    Hara, T.; Yasuda, N. (Japan Synthetic Rubber Co., Ltd., Yokkaichi (Japan). Development Center); Takeuchi, Y. (Japan Synthetic Rubber Co., Ltd., Tokyo (Japan). Electronics Project Dept.); Sakai, T.; Uchiyama, A.; Miyamura, H.; Kuriyama, N.; Ishikawa, H. (Government Industrial Research Inst., Osaka (Japan))

    1993-09-01T23:59:59.000Z

    Thermoplastic elastomers such as styrene-butadiene-styrene block copolymer (SBS) and styrene-ethylene/butylene-styrene block copolymer (SEBS) were used successfully as binding materials for metal hydride (MH) electrodes of a nickel-metal hydride battery. These binding materials have a rubber-like nature and are soluble in organic solvents. It was easy to remove the alloy powder from a used electrode for recycling. The battery performance depended on both the kind and amount of binding materials. The best discharge capacity and rate capability were obtained for MH electrodes containing 2--5 weight percent (w/o) SEBS. The particle size distributions for the alloy were examined successfully.

  9. Calculation of properties of crystalline lithium hydride using correlated wave function theory S. J. Nolan,1 M. J. Gillan,2,3 D. Alf,2,3,4 N. L. Allan,1 and F. R. Manby1

    E-Print Network [OSTI]

    Alfè, Dario

    . All calculated properties of lithium hydride and deuteride agree with empirical observations to within

  10. Coherent Atom Optics with fast metastable rare gas atoms

    SciTech Connect (OSTI)

    Grucker, J.; Baudon, J.; Karam, J.-C.; Perales, F.; Vassilev, G.; Ducloy, M. [Laboratoire de Physique des Lasers, Universite Paris 13, Avenue J.B. Clement, 93430-Villetaneuse (France); Bocvarski, V. [Institute of Physics, Pregrevica 118, 11080 - Belgrade-Zemun (Serbia and Montenegro)

    2006-12-01T23:59:59.000Z

    Coherent atom optics experiments making use of an ultra-narrow beam of fast metastable atoms generated by metastability exchange are reported. The transverse coherence of the beam (coherence radius of 1.7 {mu}m for He*, 1.2 {mu}m for Ne*, 0.87 {mu}m for Ar*) is demonstrated via the atomic diffraction by a non-magnetic 2{mu}m-period reflection grating. The combination of the non-scalar van der Waals (vdW) interaction with the Zeeman interaction generated by a static magnetic field gives rise to ''vdW-Zeeman'' transitions among Zeeman sub-levels. Exo-energetic transitions of this type are observed with Ne*(3P2) atoms traversing a copper micro-slit grating. They can be used as a tunable beam splitter in an inelastic Fresnel bi-prism atom interferometer.

  11. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-05-08T23:59:59.000Z

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using, a metal hydride.

  12. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1993-01-01T23:59:59.000Z

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  13. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1993-03-30T23:59:59.000Z

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  14. Quantum-fluid-dynamics approach for strong-field processes: Application to the study of multiphoton ionization and high-order harmonic generation of He and Ne atoms

    E-Print Network [OSTI]

    Chu, Shih-I

    of the hydrodynamical density and wave function in space and time. The procedure is applied to the study of multiphoton for Ne, good agreement is achieved. Four different exchange-correlation energy functionals are used systems. Among these novel high-intensity phenomena, multiple high-order har- monic generation HHG

  15. First Principles Studies of Phase Stability and Reaction Dynamics in Complex Metal Hydrides

    SciTech Connect (OSTI)

    Chou, Mei-Yin

    2014-09-29T23:59:59.000Z

    Complex metal hydrides are believed to be one of the most promising materials for developing hydrogen storage systems that can operate under desirable conditions. At the same time, these are also a class of materials that exhibit intriguing properties. We have used state-of-the-art computational techniques to study the fundamental properties of these materials.

  16. Hydrogen Internal Combustion Engine Two Wheeler with on-board Metal Hydride Storage

    E-Print Network [OSTI]

    Hydrogen Internal Combustion Engine Two Wheeler with on-board Metal Hydride Storage K. Sapru*, S, as a transition, the hydrogen internal combustion engine can lead the way to a hydrogen economy, allowing of these can ease India's dependence on foreign oil, and also eliminate the drastic power shortage, which

  17. Electrochromically switched, gas-reservoir metal hydride devices with application to energy-efficient windows

    E-Print Network [OSTI]

    concentration) in the gas volume between glass panes of the insulated glass units (IGUs). The elimination is an option but it requires well controlled gas exchange processes. Alternatively, and from many pointsElectrochromically switched, gas-reservoir metal hydride devices with application to energy

  18. Improving nickel metal hydride batteries through research in negative electrode corrosion control and novel electrode materials

    E-Print Network [OSTI]

    Alexander, Michael Scott

    1997-01-01T23:59:59.000Z

    The objective of this work is to improve the negative electrode of the metal hydride electrodes. Three areas were investigated: corrosion inhibition through Zn additives to the electrolyte, the use of AB5 and AB2 alloy mixtures, and novel AB2...

  19. Friction Stir Welding of Hydrided Titanium Alloys Mark Taylor, D.P. Field

    E-Print Network [OSTI]

    Collins, Gary S.

    Friction Stir Welding of Hydrided Titanium Alloys Mark Taylor, D.P. Field Multi-Scale Engineering for Undergraduates program under grant number EEC-0754370 During Friction Stir Welding (FSW), a non-consumable tool-state welding process, much frictional heating and force is required of the tool. This steep demand on the tool

  20. Proposal to Lead the Virtual Center on Carbon Materials, and support the Chemical Hydrides Center

    E-Print Network [OSTI]

    of nanoscale carbons, SWNTs, MWNTs by laser vaporization, chemical vapor deposition, hot wire CVD, and arc-discharge methods. Experience with dopant and/or catalyst incorporation NREL Capabilities in Carbon Materials laser by transition metal hydride complexes (funded by DOE BES) Lead DOE lab for new SiH4 production process ­ pilot

  1. First-row hydrides: Dissociation and ground state energies using quantum Monte Carlo

    E-Print Network [OSTI]

    Anderson, James B.

    First-row hydrides: Dissociation and ground state energies using quantum Monte Carlo Arne Lu, Pennsylvania 16802 Received 20 May 1996; accepted 24 July 1996 Accurate ground state energies comparable FN-DQMC method. The residual energy, the nodal error due to the error in the nodal structure

  2. Complex Hydrides for Hydrogen Storage Darlene K. Slattery and Michael D. Hampton

    E-Print Network [OSTI]

    Energy Center 1679 Clearlake Road Cocoa, FL 32922 Abstract Complex hydrides, containing a minimum of 7 must be capable of being regenerated with a minimal energy penalty. It also must release the hydrogen of combinations of these transition metal compounds for use as catalysts. It was found that titanium and iron

  3. ANALYSIS OF THE ELECTRON EXCITATION SPECTRA IN HEAVY RARE EARTH METALS, HYDRIDES AND OXIDES

    E-Print Network [OSTI]

    Boyer, Edmond

    397 ANALYSIS OF THE ELECTRON EXCITATION SPECTRA IN HEAVY RARE EARTH METALS, HYDRIDES AND OXIDES C thin evaporated foils of heavy rare earths (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in three different chemical of high energy incident electrons (75 keV) transmitted through thin foils of yttric rare earth elements

  4. Mathematical Modelling of a Metal Hydride Hydrogen Storage System Brendan David MacDonald

    E-Print Network [OSTI]

    Victoria, University of

    storage technology, such as gasoline tanks and batteries, it is important to have fast reaction ratesMathematical Modelling of a Metal Hydride Hydrogen Storage System by Brendan David MacDonald B Hydrogen Storage System by Brendan David MacDonald B.A.Sc., University of Waterloo, 2004 Supervisory

  5. Reversible Metal Hydride Thermal Energy Storage for High Temperature Power Generation Systems

    Broader source: Energy.gov [DOE]

    This presentation was delivered at the SunShot Concentrating Solar Power (CSP) Program Review 2013, held April 23–25, 2013 near Phoenix, Arizona.

  6. analysis-hydride generation-gas phase: Topics by E-print Network

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

    we derive the corresponding equilibrium distribution. This formulation leads us to the maximum entropy distribution that captures pair-wise phase relationships. To solve the...

  7. Threat of Hydride Re-orientation to Spent Fuel Integrity During Transportation Accidents: Myth or Reality?

    SciTech Connect (OSTI)

    Rashid, Joe [ANATECH, 5435 Oberlin Drive, San Diego, CA 92121 (United States); Machiels, Albert [EPRI, 3420 Hillview Avenue, Palo Alto, CA 94304 (United States)

    2007-07-01T23:59:59.000Z

    The source-term study conducted by Sandia National Laboratories nearly two decades ago for the spent fuel inventory known at the time, which was in the low-to-medium burnup range ({approx}35 GWd/MTU), showed that the effects of transportation accidents on spent fuel failures, and consequential radioactivity release to the environment, were relatively benign. However, with today's discharged fuel burnups routinely greater than 45 GWd/MTU, potential hydride reorientation during interim dry storage, and its effects on cladding properties, has become one of the primary concerns for spent fuel transportation. Laboratory tests of un-irradiated cladding specimens subjected to heat treatments promoting hydride dissolution followed by re-precipitation in the radial direction have shown that relatively moderate concentrations ({approx}70 ppm) of radial hydrides can significantly degrade cladding ductility, at least at room temperature. The absence of specific data that are relevant to high-burnup spent fuel under dry storage conditions have led to the conjecture, deduced from those tests, that massive cladding failures, possibly resulting in fuel reconfiguration, can be expected during cask drop events. Such conclusions are not borne out by the findings in this paper. The analysis results indicate that cladding failure is bi-modal: a state of failure initiation at the cladding ID remaining as part-wall damage with less than 2% probability of occurrence, and a through-wall failure at a probability of 1 E-5. These results indicate that spent fuel conditions that could promote the formation of radial hydrides during dry storage are not sufficient to produce radial hydrides concentrations of significant levels to cause major threat to spent fuel integrity. It is important to note in this regard that the through-wall cladding failure probability of 1 E-5 is of the same order of magnitude as calculated in the cited Sandia study for low burnup fuel. (authors)

  8. URANIUM METAL POWDER PRODUCTION, PARTICLE DISTRIBUTION ANALYSIS, AND REACTION RATE STUDIES OF A HYDRIDE-DEHYDRIDE PROCESS 

    E-Print Network [OSTI]

    Sames, William

    2011-08-08T23:59:59.000Z

    Work was done to study a hydride-dehydride method for producing uranium metal powder. Particle distribution analysis was conducted using digital microscopy and grayscale image analysis software. The particle size was found to be predominantly...

  9. Atom Interferometry

    ScienceCinema (OSTI)

    Mark Kasevich

    2010-01-08T23:59:59.000Z

    Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton?s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

  10. Fast, Quantitative, and Nondestructive Evaluation on Hydrided LWR Fuel Cladding by Small Angle Incoherent Neutron Scattering of Hydrogen

    SciTech Connect (OSTI)

    Yan, Yong [ORNL; Qian, Shuo [ORNL; Littrell, Ken [ORNL; Parish, Chad M [ORNL; Plummer, Lee K [ORNL

    2015-01-01T23:59:59.000Z

    A non-destructive neutron scattering method to precisely measure the uptake of hydrogen and the distribution of hydride precipitates in light water reactor (LWR) fuel cladding was developed. Zircaloy-4 cladding used in commercial LWRs was used to produce hydrided specimens. The hydriding apparatus consists of a closed stainless steel vessel that contains Zr alloy specimens and hydrogen gas. Following hydrogen charging, the hydrogen content of the hydrided specimens was measured using the vacuum hot extraction method, by which the samples with desired hydrogen concentration were selected for the neutron study. Optical microscopy shows that our hydriding procedure results in uniform distribution of circumferential hydrides across the wall. Small angle neutron incoherent scattering was performed in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Our study demonstrates that the hydrogen in commercial Zircaloy-4 cladding can be measured very accurately in minutes by this nondestructive method over a wide range of hydrogen concentrations from a very small amount ( 20 ppm) to over 1000 ppm. The hydrogen distribution in a tube sample was obtained by scaling the neutron scattering rate with a factor determined by a calibration process using standard, destructive direct chemical analysis methods on the specimens. This scale factor can be used in future tests with unknown hydrogen concentrations, thus providing a nondestructive method for absolute hydrogen concentration determination.

  11. Method to predict relative hydriding within a group of zirconium alloys under nuclear irradiation

    DOE Patents [OSTI]

    Johnson, A.B. Jr.; Levy, I.S.; Trimble, D.J.; Lanning, D.D.; Gerber, F.S.

    1990-04-10T23:59:59.000Z

    An out-of-reactor method for screening to predict relative in-reactor hydriding behavior of zirconium-based materials is disclosed. Samples of zirconium-based materials having different compositions and/or fabrication methods are autoclaved in a relatively concentrated (0.3 to 1.0M) aqueous lithium hydroxide solution at constant temperatures within the water reactor coolant temperature range (280 to 316 C). Samples tested by this out-of-reactor procedure, when compared on the basis of the ratio of hydrogen weight gain to oxide weight gain, accurately predict the relative rate of hydriding for the same materials when subject to in-reactor (irradiated) corrosion. 1 figure.

  12. Theoretical Standard Model Rates of Proton to Neutron Conversions Near Metallic Hydride Surfaces

    E-Print Network [OSTI]

    Widom, A

    2006-01-01T23:59:59.000Z

    The process of radiation induced electron capture by protons or deuterons producing new ultra low momentum neutrons and neutrinos may be theoretically described within the standard field theoretical model of electroweak interactions. For protons or deuterons in the neighborhoods of surfaces of condensed matter metallic hydride cathodes, such conversions are determined in part by the collective plasma modes of the participating charged particles, e.g. electrons and protons. The radiation energy required for such low energy nuclear reactions may be supplied by the applied voltage required to push a strong charged current across a metallic hydride surface employed as a cathode within a chemical cell. The electroweak rates of the resulting ultra low momentum neutron production are computed from these considerations.

  13. Improving nickel metal hydride batteries through research in negative electrode corrosion control and novel electrode materials 

    E-Print Network [OSTI]

    Alexander, Michael Scott

    1997-01-01T23:59:59.000Z

    on the Adsorption of Hydrogen on and Absorption into Metal, Alloys, and Intermetallics, The Electrochemical Society, PV 97-16, p. 277. vn1 TABLE OF CONTENTS ABSTRACT Page DEDICATION. lv ACKNOWLEGEMENTS . TABLE OF CONTENTS vnr LIST OF FIGURES. . LIST... of a new family of the intermetallic alloys containing one transition metal (4, 7, 8-10). The major family of such intermetallic alloys and their hydrides are listed in Table 1. 2 which also shows the gravimetric and volumetric hydrogen density...

  14. Engineering of the band gap and optical properties of thin films of yttrium hydride

    SciTech Connect (OSTI)

    You, Chang Chuan; Mongstad, Trygve; Maehlen, Jan Petter; Karazhanov, Smagul, E-mail: smagulk@ife.no [Institute for Energy Technology, P.O. Box 40, NO-2027 Kjeller (Norway)

    2014-07-21T23:59:59.000Z

    Thin films of oxygen-containing yttrium hydride show photochromic effect at room temperature. In this work, we have studied structural and optical properties of the films deposited at different deposition pressures, discovering the possibility of engineering the optical band gap by variation of the oxygen content. In sum, the transparency of the films and the wavelength range of photons triggering the photochromic effect can be controlled by variation of the deposition pressure.

  15. Non-stoichiometric AB5 alloys for metal hydride electrodes

    DOE Patents [OSTI]

    Reilly, James J. (Bellport, NY); Adzic, Gordana D. (Setauket, NY); Johnson, John R. (Calverton, NY); Vogt, Thomas (Cold Spring Harbor, NY); McBreen, James (Bellport, NY)

    2001-01-01T23:59:59.000Z

    The present invention provides a non-stoichiometric alloy comprising a composition having the formula AB.sub.5+X an atomic ratio wherein A is selected from the group consisting of the rare earth metals, yttrium, mischmetal, or a combination thereof; B is nickel and tin, or nickel and tin and at least a third element selected from the group consisting of the elements in group IVA of the periodic table, aluminum, manganese, iron, cobalt, copper, antimony or a combination thereof; X is greater than 0 and less than or equal to about 2.0; and wherein at least one substituted A site is occupied by at least one of the B elements. An electrode incorporating said alloy and an electrochemical cell incorporating said electrode are also described.

  16. Draft of M2 Report on Integration of the Hybrid Hydride Model into INL’s MBM Framework for Review

    SciTech Connect (OSTI)

    Tikare, Veena; Weck, Philippe F.; Schultz, Peter A.; Clark, Blythe; Glazoff, Michael; Homer, Eric

    2014-07-01T23:59:59.000Z

    This report documents the development, demonstration and validation of a mesoscale, microstructural evolution model for simulation of zirconium hydride {delta}-ZrH{sub 1.5} precipitation in the cladding of used nuclear fuels that may occur during long-term dry storage. While the Zr-based claddings are manufactured free of any hydrogen, they absorb hydrogen during service, in the reactor by a process commonly termed ‘hydrogen pick-up’. The precipitation and growth of zirconium hydrides during dry storage is one of the most likely fuel rod integrity failure mechanisms either by embrittlement or delayed hydride cracking of the cladding (Hanson et al., 2011). While the phenomenon is well documented and identified as a potential key failure mechanism during long-term dry storage (Birk et al., 2012 and NUREG/CR-7116), the ability to actually predict the formation of hydrides is poor. The model being documented in this work is a computational capability for the prediction of hydride formation in different claddings of used nuclear fuels. This work supports the Used Fuel Disposition Research and Development Campaign in assessing the structural engineering performance of the cladding during and after long-term dry storage. This document demonstrates a basic hydride precipitation model that is built on a recently developed hybrid Potts-phase field model that combines elements of Potts-Monte Carlo and the phase-field models (Homer et al., 2013; Tikare and Schultz, 2012). The model capabilities are demonstrated along with the incorporation of the starting microstructure, thermodynamics of the Zr-H system and the hydride formation mechanism.

  17. Study on generating of thermal neutron scattering cross sections for LiH

    SciTech Connect (OSTI)

    Wang, L.; Jiang, X.; Zhao, Z.; Chen, L. [Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

    2013-07-01T23:59:59.000Z

    LiH is designated as a promising moderator and shielding material because of its low density, high melting point and large fraction of H atoms. However, lack of the thermal neutron cross sections of LiH makes numerical calculation deviate from experimental data to some extent. As a result, it is necessary to study LiH thermal kernel effect. The phonon property of LiH has been investigated by first-principles calculations using the plane-wave pseudo potential method with CASTEP code. The scattering law and the thermal neutron scattering cross sections for Li and H have been generated using this distribution. The results have been compared with zirconium hydride data. The GASKET and NJOY/LEAPR codes have been used in the calculation of scattering law, whose results have been compared with the reference; the discrepancy mainly comes from phonon spectrums and its expansion. LEAPR had the capability to compute scattering through larger energy and momentum transfers than GASKET did. By studying LiH phonon spectrum and constructing the model of LiH thermal kernel and scattering matrix, the ACE format LiH thermal neutron cross sections for MCNP software could be made and used for reactor Neutronics calculation. (authors)

  18. Measuring Atomic Properties with an Atom Interferometer

    E-Print Network [OSTI]

    Roberts, Tony David

    2006-06-28T23:59:59.000Z

    Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths,

  19. Identification of a new pseudo-binary hydroxide during calendar corrosion of (La, Mg)2Ni7-type hydrogen storage alloys for Nickel-Metal Hydride batteries

    E-Print Network [OSTI]

    Boyer, Edmond

    hydrogen storage alloys for Nickel-Metal Hydride batteries J. Monnier 1 , H. Chen 1 , S. Joiret2,3 , J-MH batteries have been extensively studied during calendar storage and cycling [6-8]. In these alloys To improve the performances of Nickel-Metal Hydride batteries, an important step is the understanding

  20. Isotope exchange kinetics in metal hydrides I : TPLUG model.

    SciTech Connect (OSTI)

    Larson, Rich; James, Scott Carlton; Nilson, Robert H.

    2011-05-01T23:59:59.000Z

    A one-dimensional isobaric reactor model is used to simulate hydrogen isotope exchange processes taking place during flow through a powdered palladium bed. This simple model is designed to serve primarily as a platform for the initial development of detailed chemical mechanisms that can then be refined with the aid of more complex reactor descriptions. The one-dimensional model is based on the Sandia in-house code TPLUG, which solves a transient set of governing equations including an overall mass balance for the gas phase, material balances for all of the gas-phase and surface species, and an ideal gas equation of state. An energy equation can also be solved if thermodynamic properties for all of the species involved are known. The code is coupled with the Chemkin package to facilitate the incorporation of arbitrary multistep reaction mechanisms into the simulations. This capability is used here to test and optimize a basic mechanism describing the surface chemistry at or near the interface between the gas phase and a palladium particle. The mechanism includes reversible dissociative adsorptions of the three gas-phase species on the particle surface as well as atomic migrations between the surface and the bulk. The migration steps are more general than those used previously in that they do not require simultaneous movement of two atoms in opposite directions; this makes possible the creation and destruction of bulk vacancies and thus allows the model to account for variations in the bulk stoichiometry with isotopic composition. The optimization code APPSPACK is used to adjust the mass-action rate constants so as to achieve the best possible fit to a given set of experimental data, subject to a set of rigorous thermodynamic constraints. When data for nearly isothermal and isobaric deuterium-to-hydrogen (D {yields} H) and hydrogen-to-deuterium (H {yields} D) exchanges are fitted simultaneously, results for the former are excellent, while those for the latter show pronounced deviations at long times. These discrepancies can be overcome by postulating the presence of a surface poison such as carbon monoxide, but this explanation is highly speculative. When the method is applied to D {yields} H exchanges intentionally poisoned by known amounts of CO, the fitting results are noticeably degraded from those for the nominally CO-free system but are still tolerable. When TPLUG is used to simulate a blowdown-type experiment, which is characterized by large and rapid changes in both pressure and temperature, discrepancies are even more apparent. Thus, it can be concluded that the best use of TPLUG is not in simulating realistic exchange scenarios, but in extracting preliminary estimates for the kinetic parameters from experiments in which variations in temperature and pressure are intentionally minimized.

  1. Mathematical model of a NiOOH/metal hydride cell. Final report, September 15, 1993--November 14, 1996

    SciTech Connect (OSTI)

    White, R.E.; Popov, B.N.

    1996-12-31T23:59:59.000Z

    One of the objectives of work on the nickel/metal hydride cell has been to develop a mathematical model of the performance of the cell. This is a summary of work to date and is meant to be a Final Report of the BES project. Mathematical model of the nickel/metal hydride cell depends on the kinetics, thermodynamics, and transport properties of the metal hydride electrode. Consequently, investigations were carried out to determine: (1) the exchange current density and the equilibrium potential as a function of hydrogen content in the electrode; (2) the hydrogen diffusion coefficient in the bulk of the alloy; (3) the hydrogen reaction rate order; (4) the symmetry factor for hydrogen evolution reaction and (5) to determine the reaction mechanisms of the hydrogen charge and discharge processes including overcharge and overdischarge mechanism.

  2. Atomic physics: An almost lightless laser

    E-Print Network [OSTI]

    Vuletic, Vladan

    Lasers are often described in terms of a light field circulating in an optical resonator system. Now a laser has been demonstrated in which the field resides primarily in the atomic medium that is used to generate the light.

  3. Metal hydride/chemical heat-pump development project. Phase I. Final report

    SciTech Connect (OSTI)

    Argabright, T.A.

    1982-02-01T23:59:59.000Z

    The metal hydride/chemical heat pump (MHHP) is a chemical heat pump containing two hydrides for the storage and/or recovery of thermal energy. It utilizes the heat of reaction of hydrogen with specific metal alloys. The MHHP design can be tailored to provide heating and/or cooling or temperature upgrading over a wide range of input and ambient temperatures. The system can thus be used with a variety of heat sources including waste heat, solar energy or a fossil fuel. The conceptual design of the MHHP was developed. A national market survey including a study of applications and market sectors was conducted. The technical tasks including conceptual development, thermal and mechanical design, laboratory verification of design and material performance, cost analysis and the detailed design of the Engineering Development Test Unit (EDTU) were performed. As a result of the market study, the temperature upgrade cycle of the MHHP was chosen for development. Operating temperature ranges for the upgrader were selected to be from 70 to 110/sup 0/C (160 to 230/sup 0/F) for the source heat and 140 to 190/sup 0/C (280 to 375/sup 0/F) for the product heat. These ranges are applicable to many processes in industries such as food, textile, paper and pulp, and chemical. The hydride pair well suited for these temperatures is LaNi/sub 5//LaNi/sub 4/ /sub 5/Al/sub 0/ /sub 5/. The EDTU was designed for the upgrade cycle. It is a compact finned tube arrangement enclosed in a pressure vessel. This design incorporates high heat transfer and low thermal mass in a system which maximizes the coefficient of performance (COP). It will be constructed in Phase II. Continuation of this effort is recommended.

  4. Metal hydrides as electrode/catalyst materials for oxygen evolution/reduction in electrochemical devices

    DOE Patents [OSTI]

    Bugga, Ratnakumar V. (Arcadia, CA); Halpert, Gerald (Pasadena, CA); Fultz, Brent (Pasadena, CA); Witham, Charles K. (Pasadena, CA); Bowman, Robert C. (La Mesa, CA); Hightower, Adrian (Whittier, CA)

    1997-01-01T23:59:59.000Z

    An at least ternary metal alloy of the formula, AB.sub.(5-Y)X(.sub.y), is claimed. In this formula, A is selected from the rare earth elements, B is selected from the elements of groups 8, 9, and 10 of the periodic table of the elements, and X includes at least one of the following: antimony, arsenic, and bismuth. Ternary or higher-order substitutions, to the base AB.sub.5 alloys, that form strong kinetic interactions with the predominant metals in the base metal hydride are used to form metal alloys with high structural integrity after multiple cycles of hydrogen sorption.

  5. Theory of Hydride-Proton Transfer (HPT) Carbonyl Reduction by [Os(III)(tpy)(Cl)(NH=CHCH3)(NSAr)

    SciTech Connect (OSTI)

    Ess, Daniel H.; Schauer, Cynthia; Meyer, Thomas J.

    2010-01-01T23:59:59.000Z

    Quantum mechanical analysis reveals that carbonyl reduction of aldehydes and ketones by the imine-based reductant cis-[Os{sup III}(tpy)(Cl)(NH?CHCH{sub 3})(NSAr)] (2), which is accessible by reduction of the analogous nitrile, occurs by hydride-proton transfer (HPT) involving both the imine and sulfilimido ligands. In carbonyl reduction, water or alcohol is necessary to significantly lower the barrier for proton shuttling between ligands. The ?N(H)SAr group activates the carbonyl group through hydrogen bonding while the ?NC(H)CH{sub 3} ligand delivers the hydride.

  6. CRADA (AL-C-2009-02) Final Report: Phase I. Lanthanum-based Start Materials for Hydride Batteries

    SciTech Connect (OSTI)

    Gschneidner, Jr., Karl [Ames Laboratory; Schmidt, Frederick [Ames Laboratory] [Ames Laboratory; Frerichs, A.E. [Ames Laboratory] [Ames Laboratory; Ament, Katherine A. [Ames Laboratory] [Ames Laboratory

    2013-05-01T23:59:59.000Z

    The purpose of Phase I of this work is to focus on developing a La-based start material for making nickel-metal (lanthanum)-hydride batteries based on our carbothermic-silicon process. The goal is to develop a protocol for the manufacture of (La{sub 1-x}R{sub x})(Ni{sub 1-y}M{sub y})(Si{sub z}), where R is a rare earth metal and M is a non-rare earth metal, to be utilized as the negative electrode in nickel-metal hydride (NiMH) rechargeable batteries.

  7. Engineering atom-atom thermal entanglement via two-photon process

    E-Print Network [OSTI]

    Y. Q. Guo; L. Zhou; H. S. Song

    2005-09-21T23:59:59.000Z

    We study the system that two atoms simultaneously interact with a single-mode thermal field via different couplings and different spontaneous emission rates when two-photon process is involved. It is found that we indeed can employ the different couplings to produce the atom-atom thermal entanglement in two-photon process. The different atomic spontaneous emission rates are also utilizable in generating thermal entanglement. We also investigate the effect of the cavity leakage. To the initial atomic state $|ee> ,$a slight leakage can relieve the restriction of interaction time and we can obtain a large and steady entanglement.

  8. A Novel Zr-1Nb Alloy and a New Look at Hydriding

    SciTech Connect (OSTI)

    Robert D. Mariani; James I. Cole; Assel Aitkaliyeva

    2013-09-01T23:59:59.000Z

    A novel Zr-1Nb has begun development based on a working model that takes into account the hydrogen permeabilities for zirconium and niobium metals. The beta-Nb secondary phase particles (SPPs) in Zr-1Nb are believed to promote more rapid hydrogen dynamics in the alloy in comparison to other zirconium alloys. Furthermore, some hydrogen release is expected at the lower temperatures corresponding to outages when the partial pressure of H2 in the coolant is less. These characteristics lessen the negative synergism between corrosion and hydriding that is otherwise observed in cladding alloys without niobium. In accord with the working model, development of nanoscale precursors was initiated to enhance the performance of existing Zr-1Nb alloys. Their characteristics and properties can be compared to oxide-dispersion strengthened alloys, and material additions have been proposed to zirconium-based LWR cladding to guard further against hydriding and to fix the size of the SPPs for microstructure stability enhancements. A preparative route is being investigated that does not require mechanical alloying, and 10 nanometer molybdenum particles have been prepared which are part of the nanoscale precursors. If successful, the approach has implications for long term dry storage of used fuel and for new routes to nanoferritic and ODS alloys.

  9. Method of performing MRI with an atomic magnetometer

    DOE Patents [OSTI]

    Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

    2013-08-27T23:59:59.000Z

    A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

  10. Method of performing MRI with an atomic magnetometer

    DOE Patents [OSTI]

    Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

    2012-11-06T23:59:59.000Z

    A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

  11. THE CRYSTAL STRUCTURE OF NICKEL HYDRIDE By J. W. CABLE, E. O. WOLLAN, and W. C. KOEHLER,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    460. THE CRYSTAL STRUCTURE OF NICKEL HYDRIDE By J. W. CABLE, E. O. WOLLAN, and W. C. KOEHLER, Oak Ridge National Laboratory, Oak Ridge, Tennessee. Résumé. 2014 L'hydrure de nickel est cubique à faces centrées. H occupe les sites octaédriques avec un rapport H/Ni égal à 0,6 ± 0,1. Abstract. 2014 Nickel

  12. Verification and Validation Strategy for Implementation of Hybrid Potts-Phase Field Hydride Modeling Capability in MBM

    SciTech Connect (OSTI)

    Jason D. Hales; Veena Tikare

    2014-04-01T23:59:59.000Z

    The Used Fuel Disposition (UFD) program has initiated a project to develop a hydride formation modeling tool using a hybrid Potts­phase field approach. The Potts model is incorporated in the SPPARKS code from Sandia National Laboratories. The phase field model is provided through MARMOT from Idaho National Laboratory.

  13. atom-atom collisions: Topics by E-print Network

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

    Atomic Safronova, Marianna 3 Atom-atom correlations in colliding Bose-Einstein condensates Quantum Physics (arXiv) Summary: We analyze atom-atom correlations in the s-wave...

  14. Metal Hydrides

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment3311, 3312), OctoberMay 18-19,DepartmentEnergyMetalMetal

  15. Mechanistic Insights into Hydride Transfer for Catalytic Hydrogenation of CO2 with Cobalt Complexes

    SciTech Connect (OSTI)

    Kumar, Neeraj; Camaioni, Donald M.; Dupuis, Michel; Raugei, Simone; Appel, Aaron M.

    2014-08-21T23:59:59.000Z

    The catalytic hydrogenation of CO2 to formate by Co(dmpe)2H can proceeds via direct hydride transfer or via CO2 coordination to Co followed by reductive elimination of formate. Both pathways have activation barriers consistent with experiment (~17.5 kcal/mol). Controlling the basicity of Co by ligand design is key to improve catalysis. The research by N.K., D.M.C. and A.M.A. was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. The research by S.R. and M.D. was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for the DOE by Battelle.

  16. LaNi{sub 5}-based metal hydride electrode in Ni-MH rechargeable cells

    DOE Patents [OSTI]

    Bugga, R.V.; Fultz, B.; Bowman, R.; Surampudi, S.R.; Witham, C.K.; Hightower, A.

    1999-03-30T23:59:59.000Z

    An at least ternary metal alloy of the formula AB{sub (Z-Y)}X{sub (Y)} is disclosed. In this formula, A is selected from the rare earth elements, B is selected from the elements of Groups 8, 9, and 10 of the Periodic Table of the Elements, and X includes at least one of the following: antimony, arsenic, germanium, tin or bismuth. Z is greater than or equal to 4.8 and less than or equal to 6.0. Y is greater than 0 and less than 1. Ternary or higher-order substitutions to the base AB{sub 5} alloys that form strong kinetic interactions with the predominant metals in the base metal hydride are used to form metal alloys with high structural integrity after multiple cycles of hydrogen sorption. 16 figs.

  17. Raman Spectroscopy of Lithium Hydride Corrosion: Selection of an Appropriate Excitation Wavelength to Minimize Fluorescence

    SciTech Connect (OSTI)

    Stowe, A. C.; Smyrl, N. R.

    2011-05-26T23:59:59.000Z

    The recent interest in a hydrogen-based fuel economy has renewed research into metal hydride chemistry. Many of these compounds react readily with water to release hydrogen gas and form a caustic. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFT) has been used to study the hydrolysis reaction. The LiOH stretch appears at 3670 cm{sup -1}. Raman spectroscopy is a complementary technique that employs monochromatic excitation (laser) allowing access to the low energy region of the vibrational spectrum (<600 cm{sup -1}). Weak scattering and fluorescence typically prevent Raman from being used for many compounds. The role of Li{sub 2}O in the moisture reaction has not been fully studied for LiH. Li{sub 2}O can be observed by Raman while being hidden in the Infrared spectrum.

  18. Quantum Simulation of Helium Hydride in a Solid-State Spin Register

    E-Print Network [OSTI]

    Ya Wang; Florian Dolde; Jacob Biamonte; Ryan Babbush; Ville Bergholm; Sen Yang; Ingmar Jakobi; Philipp Neumann; Alán Aspuru-Guzik; James D. Whitfield; Jörg Wrachtrup

    2014-05-12T23:59:59.000Z

    \\emph{Ab initio} computation of molecular properties is one of the most promising applications of quantum computing. While this problem is widely believed to be intractable for classical computers, efficient quantum algorithms exist which have the potential to vastly accelerate research throughput in fields ranging from material science to drug discovery. Using a solid-state quantum register realized in a nitrogen-vacancy (NV) defect in diamond, we compute the bond dissociation curve of the minimal basis helium hydride cation, HeH$^+$. Moreover, we report an energy uncertainty (given our model basis) of the order of $10^{-14}$ Hartree, which is ten orders of magnitude below desired chemical precision. As NV centers in diamond provide a robust and straightforward platform for quantum information processing, our work provides several important steps towards a fully scalable solid state implementation of a quantum chemistry simulator.

  19. Predicting the Reactivity of Hydride Donors in Water: Thermodynamic Constants for Hydrogen

    SciTech Connect (OSTI)

    Connelly, Samantha J.; Wiedner, Eric S.; Appel, Aaron M.

    2015-01-01T23:59:59.000Z

    Chemical reactivity of hydride complexes can be predicted by comparing bond strengths for homolytic and heterolytic cleavage of bonds to hydrogen. To determine these bond strengths, thermodynamic constants for H+, H•, H–, and H2 are essential and need to be used uniformly to enable the prediction of reactivity and equilibria. One of the largest challenges is quantifying the stability of solvated H– in water, which is discussed. Due to discrepancies in the literature for the constants used in water, we propose the use of a set of self-consistent constants with convenient standard states. The work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences.

  20. Erroneous Wave Functions of Ciuchi et al for Collective Modes in Neutron Production on Metallic Hydride Cathodes

    E-Print Network [OSTI]

    Widom, A; Larsen, L

    2012-01-01T23:59:59.000Z

    There is a recent comment (Ciuchi et al., 2012) concerning the theory of collective many body effects on the neutron production rates in a chemical battery cathode. Ciuchi et al employ an inverse beta decay expression that contains a two body amplitude. Only one electron and one proton may exist in the Ciuchi et al model initial state wave function. A flaw in their reasoning is that one cannot in reality describe collective many body correlations with only a two particle wave function. One needs very many particles to describe collective effects. In the model wave functions of Ciuchi et al there are no metallic hydrides, there are no cathodes and there are no chemical batteries. Employing a wave function with only one electron and one proton is inadequate for describing collective metallic hydride surface quantum plasma physics in cathodes accurately.

  1. Erroneous Wave Functions of Ciuchi et al for Collective Modes in Neutron Production on Metallic Hydride Cathodes

    E-Print Network [OSTI]

    A. Widom; Y. N. Srivastava; L. Larsen

    2012-10-17T23:59:59.000Z

    There is a recent comment (Ciuchi et al., 2012) concerning the theory of collective many body effects on the neutron production rates in a chemical battery cathode. Ciuchi et al employ an inverse beta decay expression that contains a two body amplitude. Only one electron and one proton may exist in the Ciuchi et al model initial state wave function. A flaw in their reasoning is that one cannot in reality describe collective many body correlations with only a two particle wave function. One needs very many particles to describe collective effects. In the model wave functions of Ciuchi et al there are no metallic hydrides, there are no cathodes and there are no chemical batteries. Employing a wave function with only one electron and one proton is inadequate for describing collective metallic hydride surface quantum plasma physics in cathodes accurately.

  2. Generation of graph-state streams

    E-Print Network [OSTI]

    Daniel Ballester; Jaeyoon Cho; M. S. Kim

    2010-12-08T23:59:59.000Z

    We propose a protocol to generate a stream of mobile qubits in a graph state through a single stationary parent qubit and discuss two types of its physical implementation, namely, the generation of photonic graph states through an atom-like qubit and those of flying atoms through a cavity-mode photonic qubit. The generated graph states fall into an important class that can hugely reduce the resource requirement of fault-tolerant linear optics quantum computation, which was previously known to be far from realistic. In regard to the flying atoms, we also propose a heralded generation scheme, which allows for high-fidelity graph states even under the photon loss.

  3. Development of a lithium hydride powered hydrogen generator for use in long life, low power PEM fuel cell power supplies

    E-Print Network [OSTI]

    Strawser, Daniel DeWitt

    2012-01-01T23:59:59.000Z

    This thesis studies a hybrid PEM fuel cell system for use in low power, long life sensor networks. PEM fuel cells offer high efficiency and environmental friendliness but have not been widely adopted due to cost, reliability, ...

  4. Atomizing nozzle and process

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Molnar, H.M.

    1993-07-20T23:59:59.000Z

    High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

  5. Study atom-vacuum interaction by the weak measurement technique

    E-Print Network [OSTI]

    M. Zhang; S. Y. Zhu

    2014-10-27T23:59:59.000Z

    Quantum weak measurement attracts much interests recently [Rev. Mod. Phys. 86, 307 (2014)], as it could amplify some weak signals and provide a technique to observe the nonclassical phenomenons. Here, we apply this technique to study the interaction between the free atoms and the vacuum in a cavity. Due to the gradient field in the vacuum cavity, the external orbital motions and the internal electronic states of the atoms can be weakly coupled via the atom-field electric-dipole interaction. We show an interesting phenomenon that, within the properly post-selected internal states, the weak atom-vacuum interaction could generate a large change to the external motions of atoms.

  6. Driven Ratchets for Cold Atoms

    E-Print Network [OSTI]

    Renzoni, F

    2011-01-01T23:59:59.000Z

    Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

  7. Driven Ratchets for Cold Atoms

    E-Print Network [OSTI]

    F. Renzoni

    2011-12-05T23:59:59.000Z

    Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

  8. Atomic oxygen flux determined by mixed-phase Ag/Ag2O deposition...

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

    oxygen flux determined by mixed-phase AgAg2O deposition. Atomic oxygen flux determined by mixed-phase AgAg2O deposition. Abstract: The flux of atomic oxygen generated in a...

  9. Atomic swelling upon compression

    E-Print Network [OSTI]

    V. K. Dolmatov; J. L. King

    2012-08-18T23:59:59.000Z

    The hydrogen atom under the pressure of a spherical penetrable confinement potential of a decreasing radius $r_{0}$ is explored, as a case study. A novel counter-intuitive effect of atomic swelling rather than shrinking with decreasing $r_{0}$ is unraveled, when $r_{0}$ reaches, and remains smaller than, a certain critical value. Upon swelling, the size of the atom is shown to increase by an order of magnitude, or more, compared to the size of the free atom. Examples of changes of photoabsorption properties of confined hydrogen atom upon its swelling are uncovered and demonstrated.

  10. Discovery of novel hydrogen storage materials: an atomic scale...

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

    several key capabilities to be effective: (i) accurate prediction of decomposition thermodynamics, (ii) prediction of crystal structures for unknown hydrides, and (iii) prediction...

  11. Hydride vapor phase epitaxy and characterization of high-quality ScN epilayers

    SciTech Connect (OSTI)

    Oshima, Yuichi, E-mail: OSHIMA.Yuichi@nims.go.jp; Víllora, Encarnación G.; Shimamura, Kiyoshi [Environment and Energy Materials Research Division, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2014-04-21T23:59:59.000Z

    The heteroepitaxial growth of ScN films was investigated on various substrates by hydride vapor phase epitaxy (HVPE). Single crystalline mirror-like ScN(100) and ScN(110) layers were successfully deposited on r- and m-plane sapphire substrates, respectively. Homogeneous stoichiometric films (N/Sc ratio 1.01?±?0.10) up to 40??m in thickness were deposited. Their mosaicity drastically improved with increasing the film thickness. The band gap was determined by optical methods to be 2.06?eV. Impurity concentrations including H, C, O, Si, and Cl were investigated through energy dispersive X-ray spectrometry and secondary ion mass spectrometry. As a result, it was found that the presence of impurities was efficiently suppressed in comparison with that of HVPE-grown ScN films reported in the past, which was possible thanks to the home-designed corrosion-free HVPE reactor. Room-temperature Hall measurements indicated that the residual free electron concentrations ranged between 10{sup 18}–10{sup 20}?cm{sup ?3}, which was markedly lower than the reported values. The carrier mobility increased monotonically with the decreasing in carrier concentration, achieving the largest value ever reported, 284?cm{sup 2}?V{sup ?1}?s{sup ?1} at n?=?3.7?×?10{sup 18}?cm{sup ?3}.

  12. Trends in the electron-phonon coupling parameter in some metallic hydrides

    SciTech Connect (OSTI)

    Gupta, M.; Burger, J.P.

    1981-12-15T23:59:59.000Z

    We present an evaluation of the electron-phonon coupling parameter lambda, using the McMillan formalism, for several classes of stoichiometric mono- and dihydrides with a metallic underlying fcc structure. We calculate the electronic term eta and use experimental estimates for the phonon energies when available. We derive systematic trends concerning both contributions to eta stemming, respectively, from the metallic site M and the hydrogen site H. We show that eta/sub H/ is generally small, but it may become large if the Fermi energy is in the metal s-p band as in the filled d-band transition-metal (TM) hydrides such as PdH; eta/sub H/ may also be large when a metal-hydrogen antibonding band crosses the Fermi level, a case which happens in AlH and may happen for some unstable dihydrides. The metallic contribution eta/sub M/ is calculated to be small for all stable mono- and dihydrides like PdH, NiH, ZrH/sub 2/, NbH/sub 2/, etc., but nothing in principle prevents this contribution from becoming as large as in some pure TM, if one sweeps the Fermi level through the whole metallic d band. Good agreement with the available experimental data is obtained concerning the occurrence of superconductivity in the compounds considered.

  13. Discovery of Novel Complex Metal Hydrides for Hydrogen Storage through Molecular Modeling and Combinatorial Methods

    SciTech Connect (OSTI)

    Lesch, David A; Adriaan Sachtler, J.W. J.; Low, John J; Jensen, Craig M; Ozolins, Vidvuds; Siegel, Don

    2011-02-14T23:59:59.000Z

    UOP LLC, a Honeywell Company, Ford Motor Company, and Striatus, Inc., collaborated with Professor Craig Jensen of the University of Hawaii and Professor Vidvuds Ozolins of University of California, Los Angeles on a multi-year cost-shared program to discover novel complex metal hydrides for hydrogen storage. This innovative program combined sophisticated molecular modeling with high throughput combinatorial experiments to maximize the probability of identifying commercially relevant, economical hydrogen storage materials with broad application. A set of tools was developed to pursue the medium throughput (MT) and high throughput (HT) combinatorial exploratory investigation of novel complex metal hydrides for hydrogen storage. The assay programs consisted of monitoring hydrogen evolution as a function of temperature. This project also incorporated theoretical methods to help select candidate materials families for testing. The Virtual High Throughput Screening served as a virtual laboratory, calculating structures and their properties. First Principles calculations were applied to various systems to examine hydrogen storage reaction pathways and the associated thermodynamics. The experimental program began with the validation of the MT assay tool with NaAlH4/0.02 mole Ti, the state of the art hydrogen storage system given by decomposition of sodium alanate to sodium hydride, aluminum metal, and hydrogen. Once certified, a combinatorial 21-point study of the NaAlH4 â?? LiAlH4 â??Mg(AlH4)2 phase diagram was investigated with the MT assay. Stability proved to be a problem as many of the materials decomposed during synthesis, altering the expected assay results. This resulted in repeating the entire experiment with a mild milling approach, which only temporarily increased capacity. NaAlH4 was the best performer in both studies and no new mixed alanates were observed, a result consistent with the VHTS. Powder XRD suggested that the reverse reaction, the regeneration of the alanate from alkali hydride, Al and hydrogen, was hampering reversibility. The reverse reaction was then studied for the same phase diagram, starting with LiH, NaH, and MgH2, and Al. The study was extended to phase diagrams including KH and CaH2 as well. The observed hydrogen storage capacity in the Al hexahydrides was less than 4 wt. %, well short of DOE targets. The HT assay came on line and after certification with studies on NaAlH4, was first applied to the LiNH2 - LiBH4 - MgH2 phase diagram. The 60-point study elucidated trends within the system locating an optimum material of 0.6 LiNH2 â?? 0.3 MgH2 â?? 0.1 LiBH4 that stored about 4 wt. % H2 reversibly and operated below 220 °C. Also present was the phase Li4(NH2)3BH4, which had been discovered in the LiNH2 -LiBH4 system. This new ternary formulation performed much better than the well-known 2 LiNH2 â?? MgH2 system by 50 °C in the HT assay. The Li4(NH2)3BH4 is a low melting ionic liquid under our test conditions and facilitates the phase transformations required in the hydrogen storage reaction, which no longer relies on a higher energy solid state reaction pathway. Further study showed that the 0.6 LiNH2 â?? 0.3 MgH2 â?? 0.1 LiBH4 formulation was very stable with respect to ammonia and diborane desorption, the observed desorption was from hydrogen. This result could not have been anticipated and was made possible by the efficiency of HT combinatorial methods. Investigation of the analogous LiNH2 â?? LiBH4 â?? CaH2 phase diagram revealed new reversible hydrogen storage materials 0.625 LiBH4 + 0.375 CaH2 and 0.375 LiNH2 + 0.25 LiBH4 + 0.375 CaH2 operating at 1 wt. % reversible hydrogen below 175 °C. Powder x-ray diffraction revealed a new structure for the spent materials which had not been previously observed. While the storage capacity was not impressive, an important aspect is that it boron appears to participate in a low temperature reversible reaction. The last major area of study also focused

  14. Four-level atom interferometer with trichromatic laser fields

    SciTech Connect (OSTI)

    Honda, Kazuhito; Kobayashi, Yoshiyuki; Morinaga, Atsuo [Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510 (Japan)

    2007-02-15T23:59:59.000Z

    A four-level atom interferometer comprised of three excited states and one ground state with trichromatic fields coupled between them is investigated using Zeeman sublevels of {sup 3}P{sub 1} and {sup 1}S{sub 0} states of a calcium atom. A theoretical description of the interaction of four-level atoms with trichromatic laser fields is presented and compared with the experimental results of the interference fringes which are generated by the three excited states.

  15. Please cite this article in press as: Malen, J.A., et al., Thermal hydraulic design of a hydride-fueled inverted PWR core. Nucl. Eng. Des. (2009), doi:10.1016/j.nucengdes.2009.02.026

    E-Print Network [OSTI]

    Malen, Jonathan A.

    2009-01-01T23:59:59.000Z

    Please cite this article in press as: Malen, J.A., et al., Thermal hydraulic design of a hydride hydraulic design of a hydride-fueled inverted PWR core J.A. Malena, , N.E. Todreasb , P. Hejzlarb , P and its thermal hydraulic performance is compared to that of a standard rod bundle core design also fueled

  16. Vacuum - induced stationary entanglement in radiatively coupled three - level atoms

    E-Print Network [OSTI]

    L. Derkacz; L. Jakobczyk

    2008-05-05T23:59:59.000Z

    We consider a pair of three - level atoms interacting with a common vacuum and analyze the process of entanglement production due to spontaneous emission. We show that in the case of closely separated atoms, collective damping can generate robust entanglement of the asymptotic states.

  17. Gauge invariant hydrogen atom Hamiltonian

    E-Print Network [OSTI]

    Wei-Min Sun; Xiang-Song Chen; Xiao-Fu Lu; Fan Wang

    2010-06-22T23:59:59.000Z

    For quantum mechanics of a charged particle in a classical external electromagnetic field, there is an apparent puzzle that the matrix element of the canonical momentum and Hamiltonian operators is gauge dependent. A resolution to this puzzle is recently provided by us in [2]. Based on the separation of the electromagnetic potential into pure gauge and gauge invariant parts, we have proposed a new set of momentum and Hamiltonian operators which satisfy both the requirement of gauge invariance and the relevant commutation relations. In this paper we report a check for the case of the hydrogen atom problem: Starting from the Hamiltonian of the coupled electron, proton and electromagnetic field, under the infinite proton mass approximation, we derive the gauge invariant hydrogen atom Hamiltonian and verify explicitly that this Hamiltonian is different from the Dirac Hamiltonian, which is the time translation generator of the system. The gauge invariant Hamiltonian is the energy operator, whose eigenvalue is the energy of the hydrogen atom. It is generally time-dependent. In this case, one can solve the energy eigenvalue equation at any specific instant of time. It is shown that the energy eigenvalues are gauge independent, and by suitably choosing the phase factor of the time-dependent eigenfunction, one can ensure that the time-dependent eigenfunction satisfies the Dirac equation.

  18. Variations of the infrared transmission properties with the metal{endash}insulator transition in thin films of the yttrium-hydride system

    SciTech Connect (OSTI)

    Lee, M. W.; Kuo, C. Y.; Lin, H. C.; Wang, H. C.

    2001-06-01T23:59:59.000Z

    This work investigates the variations of the infrared transmission spectra of yttrium-hydride films YH{sub x} during the hydrogen loading process for the frequency range 500{endash}4000 cm{minus}1. The results indicate that the transmittance slightly decreases in the dihydride phase, followed by a significant increase in the trihydride phase. In addition, the carrier concentration decreases, whereas the carrier relaxation time increases with hydrogen content. The hydrogen vibration modes at interstitial sites are completely screened in the dihydride phase. The screening effect decreases as the system goes through the metal{endash}insulator transition. Moreover, the screening effect can be continuously tuned by simply varying the hydrogen content in the yttrium-hydride system. Analysis indicates that the absorption intensity of the vibration mode depends on the carrier concentration. This effect can be used as a diagnostic tool for estimating the carrier concentration and hydrogen content in rare-earth hydrides. {copyright} 2001 American Institute of Physics.

  19. Improved graphite furnace atomizer

    DOE Patents [OSTI]

    Siemer, D.D.

    1983-05-18T23:59:59.000Z

    A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

  20. Atomic Collapse Observed

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

    Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

  1. Soil and Water Science Department University of Florida Phytoremediation of Arsenic Contaminated Sites: Feasibility and Optimization

    E-Print Network [OSTI]

    Ma, Lena

    - atomic fluorescence spectrometry and high performance liquid chromatography- inductively coupled plasma mass spectrometry, and scanning/transmission electron microscope equipped with energy dispersive x in the plant biomass will be accomplished using high performance liquid chromatography-hydride generation

  2. Arsenic removal and stabilization by synthesized pyrite

    E-Print Network [OSTI]

    Song, Jin Kun

    2009-05-15T23:59:59.000Z

    hydride generation atomic absorption spectrometry method for measuring arsenic species (As(III), As(V)). The synthesized pyrite was applied to remove arsenic and its maximum capacity for arsenic removal was measured in batch adsorption experiments to be 3...

  3. A coupled transport and solid mechanics formulation with improved reaction kinetics parameters for modeling oxidation and decomposition in a uranium hydride bed.

    SciTech Connect (OSTI)

    Salloum, Maher N.; Shugard, Andrew D.; Kanouff, Michael P.; Gharagozloo, Patricia E.

    2013-03-01T23:59:59.000Z

    Modeling of reacting flows in porous media has become particularly important with the increased interest in hydrogen solid-storage beds. An advanced type of storage bed has been proposed that utilizes oxidation of uranium hydride to heat and decompose the hydride, releasing the hydrogen. To reduce the cost and time required to develop these systems experimentally, a valid computational model is required that simulates the reaction of uranium hydride and oxygen gas in a hydrogen storage bed using multiphysics finite element modeling. This SAND report discusses the advancements made in FY12 (since our last SAND report SAND2011-6939) to the model developed as a part of an ASC-P&EM project to address the shortcomings of the previous model. The model considers chemical reactions, heat transport, and mass transport within a hydride bed. Previously, the time-varying permeability and porosity were considered uniform. This led to discrepancies between the simulated results and experimental measurements. In this work, the effects of non-uniform changes in permeability and porosity due to phase and thermal expansion are accounted for. These expansions result in mechanical stresses that lead to bed deformation. To describe this, a simplified solid mechanics model for the local variation of permeability and porosity as a function of the local bed deformation is developed. By using this solid mechanics model, the agreement between our reacting bed model and the experimental data is improved. Additionally, more accurate uranium hydride oxidation kinetics parameters are obtained by fitting the experimental results from a pure uranium hydride oxidation measurement to the ones obtained from the coupled transport-solid mechanics model. Finally, the coupled transport-solid mechanics model governing equations and boundary conditions are summarized and recommendations are made for further development of ARIA and other Sandia codes in order for them to sufficiently implement the model.

  4. Method and apparatus for atomic imaging

    DOE Patents [OSTI]

    Saldin, Dilano K. (Milwaukee, WI); de Andres Rodriquez, Pedro L. (Madrid, ES)

    1993-01-01T23:59:59.000Z

    A method and apparatus for three dimensional imaging of the atomic environment of disordered adsorbate atoms are disclosed. The method includes detecting and measuring the intensity of a diffuse low energy electron diffraction pattern formed by directing a beam of low energy electrons against the surface of a crystal. Data corresponding to reconstructed amplitudes of a wave form is generated by operating on the intensity data. The data corresponding to the reconstructed amplitudes is capable of being displayed as a three dimensional image of an adsorbate atom. The apparatus includes a source of a beam of low energy electrons and a detector for detecting the intensity distribution of a DLEED pattern formed at the detector when the beam of low energy electrons is directed onto the surface of a crystal. A device responsive to the intensity distribution generates a signal corresponding to the distribution which represents a reconstructed amplitude of a wave form and is capable of being converted into a three dimensional image of the atomic environment of an adsorbate atom on the crystal surface.

  5. Producing and Detecting Correlated atoms

    E-Print Network [OSTI]

    Christoph I. Westbrook; Martijn Schellekens; Aurélien Perrin; Valentina Krachmalnicoff; Jose Carlos Viana Gomes; Jean-Baptiste Trebbia; Jérôme Estève; Hong Chang; Isabelle Bouchoule; Denis Boiron; Alain Aspect; Tom Jeltes; John McNamara; Wim Hogervorst; Wim Vassen

    2006-09-04T23:59:59.000Z

    We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions.We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four-wavemixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.

  6. Nitric Oxide Production from Surface Recombination of Oxygen and Nitrogen Atoms

    E-Print Network [OSTI]

    Martín, Pino

    of hypersonic reentry vehicles. In the Earth's atmosphere, oxygen and nitrogen atoms are generated in the shock1 Nitric Oxide Production from Surface Recombination of Oxygen and Nitrogen Atoms Dusan A. Pejakovi from the recombination of oxygen and nitrogen atoms on quartz. The experiments employ two-photon laser

  7. Atomic and molecular supernovae

    SciTech Connect (OSTI)

    Liu, W.

    1997-12-01T23:59:59.000Z

    Atomic and molecular physics of supernovae is discussed with an emphasis on the importance of detailed treatments of the critical atomic and molecular processes with the best available atomic and molecular data. The observations of molecules in SN 1987A are interpreted through a combination of spectral and chemical modelings, leading to strong constraints on the mixing and nucleosynthesis of the supernova. The non-equilibrium chemistry is used to argue that carbon dust can form in the oxygen-rich clumps where the efficient molecular cooling makes the nucleation of dust grains possible. For Type Ia supernovae, the analyses of their nebular spectra lead to strong constraints on the supernova explosion models.

  8. Polar intermetallic compounds of the silicon and arsenic family elements and their ternary hydrides and fluorides

    SciTech Connect (OSTI)

    Leon-Escamilla, E.A.

    1996-10-17T23:59:59.000Z

    An investigation has been made on the effects of hydrogen and fluoride in the solid state chemistry of alkaline-earth and divalent rare-earth metal pnictide (Pn) and tetrelide (Tt) phases A{sub 5}(Pn,Tt,){sub 3}Z{sub x}, where A = Ca, Sr, Ba, Sm, Eu, Yb; Pn = As, Sb, Bi; Tt = Si, Ge, Sn, Pb and Z = H, F. Several trivalent rare-earth-metal pnictides, RE{sub 5}Pn{sub 3} (RE = Y, La, Gd, Tb, Dy, Ho, Er, Tm) and alkaline-earth-metal trielides, A{sub 5}Tr{sub 3}Z{sub x} (Tr = Ga, In, Tl) have been included in an effort to complete observed structural trends. Two main experimental techniques were followed throughout this work, (a) reactions in absence of hydrogen or under continuous high vacuum, and (b) reactions with binary metal hydrides, AH{sub x}, in closed containers. The results demonstrate that all the phases reported with the {beta}-Yb{sub 5}Sb{sub 3}-type structure in the A{sub 5}Pn{sub 3} systems are hydrogen-stabilized compounds. Reactions in absence of hydrogen lead to compounds with the Mn{sub 5}Si{sub 3}-type structure. The structure type {beta}-Yb{sub 5}Sb{sub 3} (= Ca{sub 5}SB{sub 3}F) was found to be characteristic of ternary systems and inaccurately associated with phases that form in the Y{sub 5}Bi{sub 3}-type. A new series of isomorphous Zintl compounds with the Ca{sub 16}Sb{sub 11}-type structure were prepared and studied as well. All the alkaline-earth-metal tetrelides, A{sub 5}Tt{sub 3}, that crystallize in the Cr{sub 5}B{sub 3}-type structure can be interstitially derivatized by hydrogen or fluoride. Binary and ternary compounds were characterized by Guinier powder patterns, single crystal X-ray and powder neutron diffraction techniques. In an effort to establish property-structure relationships, electrical resistivity and magnetic measurements were performed on selected systems, and the results were explained in terms of the Zintl concepts, aided by extended Hueckel band calculations.

  9. An Electrolytic Method to Form Zirconium Hydride Phases in Zirconium Alloys with Morphologies Similar to Hydrides Formed in Used Nuclear Fuel

    E-Print Network [OSTI]

    Kuhr, Samuel Houston

    2012-10-19T23:59:59.000Z

    Thermal Gradient (ECH-TG) system has the ability to generate static 20°C to 120°C temperatures for a H2SO4 and H2O bath for isothermal experiment conditions. This system was designed to accommodate a molten salt bath in future experiments to achieve higher...

  10. MOSSBAUER STUDIES OF DILUTE ERBIUM IMPURITIES IN ZIRCONIUM HYDRIDES* G.K. Shenoy, B.D. Dunlap, D.G. Westlake and A.E. Dwight*

    E-Print Network [OSTI]

    Boyer, Edmond

    MOSSBAUER STUDIES OF DILUTE ERBIUM IMPURITIES IN ZIRCONIUM HYDRIDES* G.K. Shenoy, B.D. Dunlap, D previously shown 15,6/ that Mossbauer effect measurements can be used to investigate the electronic.6 keV Mossbauer transition in 16G Er. The re- sonance spectra were measured using conventional

  11. Hydrogen-deuterium exchange of the anionic group 6B transition-metal hydrides. Convenient, in-situ-deuterium transfer reagents

    SciTech Connect (OSTI)

    Gaus, P.L.; Kao, S.C.; Darensbourg, M.Y.; Arndt, L.W.

    1984-08-22T23:59:59.000Z

    The facile exchange of hydrogen for detuerium in the anionic group 6B carbonyl hydrides HM(CO)/sub 4/L/sup -/(M = Cr, W; L = CO P(OMe)/sub 3/) has been studied in THF/sub 4/ (tetrahydrofuran) with CH/sub 3/OD, D/sub 2/O, and CH/sub 3/CO/sub 2/D. This has provided a synthesis of the deuterides, DM(CO)/sub 4/L/sup -/, as well as a convenient in situ source of deuteride reducing reagents for organic halides. A number of such reductions are described, using /sup 2/H NMR to demonstrate both selectivity and stereospecificity for certain systems. The carbonyl region of the infrared spectra of the hydrides is not affected by deuteration of the hydrides, suggesting that the M-H or M-D vibrational modes are not coupled significantly to CO vibrations in these hydrides. The mechanism of the H/D exchange and of a related H/sub 2/ elimination reaction is discussed.

  12. Metal atomization spray nozzle

    DOE Patents [OSTI]

    Huxford, T.J.

    1993-11-16T23:59:59.000Z

    A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

  13. Atomizing nozzle and method

    DOE Patents [OSTI]

    Ting, Jason (Ames, IA); Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA)

    2000-03-16T23:59:59.000Z

    A high pressure close-coupled gas atomizing nozzle includes multiple discrete gas jet discharge orifices having aerodynamically designed convergent-divergent geometry with an first converging section communicated to a gas supply manifold and to a diverging section by a constricted throat section to increase atomizing gas velocity. The gas jet orifices are oriented at gas jet apex angle selected relative to the melt supply tip apex angle to establish a melt aspiration condition at the melt supply tip.

  14. Optical atomic magnetometer

    DOE Patents [OSTI]

    Budker, Dmitry; Higbie, James; Corsini, Eric P

    2013-11-19T23:59:59.000Z

    An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

  15. Atomic mass compilation 2012

    SciTech Connect (OSTI)

    Pfeiffer, B., E-mail: bpfeiffe@uni-mainz.de [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Venkataramaniah, K. [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India)] [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India); Czok, U. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)] [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); Scheidenberger, C. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany) [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)

    2014-03-15T23:59:59.000Z

    Atomic mass reflects the total binding energy of all nucleons in an atomic nucleus. Compilations and evaluations of atomic masses and derived quantities, such as neutron or proton separation energies, are indispensable tools for research and applications. In the last decade, the field has evolved rapidly after the advent of new production and measuring techniques for stable and unstable nuclei resulting in substantial ameliorations concerning the body of data and their precision. Here, we present a compilation of atomic masses comprising the data from the evaluation of 2003 as well as the results of new measurements performed. The relevant literature in refereed journals and reports as far as available, was scanned for the period beginning 2003 up to and including April 2012. Overall, 5750 new data points have been collected. Recommended values for the relative atomic masses have been derived and a comparison with the 2003 Atomic Mass Evaluation has been performed. This work has been carried out in collaboration with and as a contribution to the European Nuclear Structure and Decay Data Network of Evaluations.

  16. Request for Support for the Conference on Super Intense Laser Atom Physics

    SciTech Connect (OSTI)

    Todd Ditmire

    2004-10-21T23:59:59.000Z

    The Conference on Super Intense Laser Atom Physics (SILAP) was held in November 2003 in Dallas, Texas. The venue for the meeting was South Fork Ranch in the outskirts of Dallas. The topics of the meeting included high harmonic generation and attosecond pulse generation, strong field interactions with molecules and clusters, particle acceleration, and relativistic laser atom interactions.

  17. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C. (Port Jefferson, NY); Wang, Chengpu (Upton, NY)

    2003-01-01T23:59:59.000Z

    An atomic force microscope utilizes a pulse release system and improved method of operation to minimize contact forces between a probe tip affixed to a flexible cantilever and a specimen being measured. The pulse release system includes a magnetic particle affixed proximate the probe tip and an electromagnetic coil. When energized, the electromagnetic coil generates a magnetic field which applies a driving force on the magnetic particle sufficient to overcome adhesive forces exhibited between the probe tip and specimen. The atomic force microscope includes two independently displaceable piezo elements operable along a Z-axis. A controller drives the first Z-axis piezo element to provide a controlled approach between the probe tip and specimen up to a point of contact between the probe tip and specimen. The controller then drives the first Z-axis piezo element to withdraw the cantilever from the specimen. The controller also activates the pulse release system which drives the probe tip away from the specimen during withdrawal. Following withdrawal, the controller adjusts the height of the second Z-axis piezo element to maintain a substantially constant approach distance between successive samples.

  18. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    A. Deltuva

    2012-03-28T23:59:59.000Z

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  19. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    Deltuva, A

    2012-01-01T23:59:59.000Z

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  20. LaNi.sub.5 is-based metal hydride electrode in Ni-MH rechargeable cells

    DOE Patents [OSTI]

    Bugga, Ratnakumar V. (Arcadia, CA); Fultz, Brent (Pasadena, CA); Bowman, Robert (La Mesa, CA); Surampudi, Subra Rao (Glendora, CA); Witham, Charles K. (Pasadena, CA); Hightower, Adrian (Pasadena, CA)

    1999-01-01T23:59:59.000Z

    An at least ternary metal alloy of the formula AB.sub.(Z-Y) X.sub.(Y) is disclosed. In this formula, A is selected from the rare earth elements, B is selected from the elements of Groups 8, 9, and 10 of the Periodic Table of the Elements, and X includes at least one of the following: antimony, arsenic, germanium, tin or bismuth. Z is greater than or equal to 4.8 and less than or equal to 6.0. Y is greater than 0 and less than 1. Ternary or higher-order substitutions to the base AB.sub.5 alloys that form strong kinetic interactions with the predominant metals in the base metal hydride are used to form metal alloys with high structural integrity after multiple cycles of hydrogen sorption.

  1. Li{sub 4}FeH{sub 6}: Iron-containing complex hydride with high gravimetric hydrogen density

    SciTech Connect (OSTI)

    Saitoh, Hiroyuki, E-mail: cyto@spring8.or.jp [Quantum Beam Science Center, Japan Atomic Energy Agency, Hyogo 679-5148 (Japan); Takagi, Shigeyuki; Matsuo, Motoaki; Aoki, Katsutoshi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Iijima, Yuki [WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Endo, Naruki [Renewable Energy Research Center, National Institute of Advanced Industrial Science and Technology, Fukushima 963-0215 (Japan); Orimo, Shin-ichi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2014-07-01T23:59:59.000Z

    Li{sub 4}FeH{sub 6}, which has the highest gravimetric hydrogen density of iron-containing complex hydrides reported so far, is synthesized by hydrogenation of a powder mixture of iron and LiH above 6.1 GPa at 900?°C. In situ synchrotron radiation X-ray diffraction measurements reveal that while kinetics require high temperature and thus high pressure for the synthesis, Li{sub 4}FeH{sub 6} is expected to be thermodynamically stable slightly below room temperature at ambient pressure; further synthetic studies to suppress the kinetic effects may enable us to synthesize Li{sub 4}FeH{sub 6} at moderate pressures. Li{sub 4}FeH{sub 6} can be recovered at ambient conditions where Li{sub 4}FeH{sub 6} is metastable.

  2. Atomic Force Microscope

    SciTech Connect (OSTI)

    Day, R.D.; Russell, P.E.

    1988-12-01T23:59:59.000Z

    The Atomic Force Microscope (AFM) is a recently developed instrument that has achieved atomic resolution imaging of both conducting and non- conducting surfaces. Because the AFM is in the early stages of development, and because of the difficulty of building the instrument, it is currently in use in fewer than ten laboratories worldwide. It promises to be a valuable tool for obtaining information about engineering surfaces and aiding the .study of precision fabrication processes. This paper gives an overview of AFM technology and presents plans to build an instrument designed to look at engineering surfaces.

  3. Iowa Powder Atomization Technologies

    ScienceCinema (OSTI)

    None

    2013-03-01T23:59:59.000Z

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  4. Iowa Powder Atomization Technologies

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  5. Elements & Compounds Atoms (Elements)

    E-Print Network [OSTI]

    Frey, Terry

    #12;Elements & Compounds #12;Atoms (Elements) Molecules (Compounds) Cells Elements & Compounds #12 #12;First shell Second shell Third shell Hydrogen 1H Lithium 3Li Sodium 11Na Beryllium 4Be Magnesium energy Higher energy (a) A ball bouncing down a flight of stairs provides an analogy for energy levels

  6. New results in atomic physics at the Advanced Light Source

    SciTech Connect (OSTI)

    Schlachter, A.S.

    1995-01-01T23:59:59.000Z

    The Advanced Light Source is the world's first low-energy third-generation synchrotron radiation source. It has been running reliably and exceeding design specifications since it began operation in October 1993. It is available to a wide community of researchers in many scientific fields, including atomic and molecular science and chemistry. Here, new results in atomic physics at the Advanced Light Source demonstrate the opportunities available in atomic and molecular physics at this synchrotron light source. The unprecedented brightness allows experiments with high flux, high spectral resolution, and nearly 100% linear polarization.

  7. Atom-by-atom nucleation and growth of graphene nanopores

    E-Print Network [OSTI]

    Golovchenko, Jene A.

    Atom-by-atom nucleation and growth of graphene nanopores Christopher J. Russoa,b and J. A February 17, 2012 (received for review December 9, 2011) Graphene is an ideal thin membrane substrate structures in graphene with atomic preci- sion. It consists of inducing defect nucleation centers with ener

  8. Multimode Raman light-atom interface in warm atomic ensemble as multiple three-mode quantum operations

    E-Print Network [OSTI]

    Micha? Parniak; Daniel P?cak; Wojciech Wasilewski

    2015-06-08T23:59:59.000Z

    We analyze the properties of a Raman quantum light-atom interface in long atomic ensemble and its applications as a quantum memory or two-mode squeezed state generator. We include both Stokes and anti-Stokes scattering and the effects of Doppler broadening in buffer gas assuming frequent velocity-averaging collisions. We find the Green functions describing multimode transformation from input to output fields of photons and atomic excitations. Further considerations (following Sec. II D) are incorrect due to a mistake in finding a proper mode basis. Correct description is being worked out and should be published soon.

  9. Atomic phenomena in dense plasmas

    SciTech Connect (OSTI)

    Weisheit, J.C.

    1981-03-01T23:59:59.000Z

    The following chapters are included: (1) the plasma environment, (2) perturbations of atomic structure, (3) perturbations of atomic collisions, (4) formation of spectral lines, and (5) dielectronic recombination. (MOW)

  10. Atom chip apparatus for experiments with ultracold rubidium and potassium gases

    SciTech Connect (OSTI)

    Ivory, M. K.; Ziltz, A. R.; Fancher, C. T.; Pyle, A. J.; Sensharma, A.; Chase, B.; Field, J. P.; Garcia, A.; Aubin, S., E-mail: saaubi@wm.edu [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187 (United States); Jervis, D. [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)] [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)

    2014-04-15T23:59:59.000Z

    We present a dual chamber atom chip apparatus for generating ultracold {sup 87}Rb and {sup 39}K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 10{sup 4} {sup 87}Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold {sup 39}K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multicoil magnetic transport system, the atom chip, and two optical dipole traps. Due in part to the use of light-induced atom desorption, the laser cooling chamber features a sufficiently good vacuum to also support optical dipole trap-based experiments. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems.

  11. Possible hydride and methide transfer reactions: Reactions of Fe(CO){sub 4}R{sup -} (R=H, CH{sub 3}) and W(CO){sub 5}R{sup -} (R = H, CH{sub 3}, CL, Br, I) with metal carbonyl cations

    SciTech Connect (OSTI)

    Wang, P.; Striejewske, W.S.; Atwood, J.D. [State Univ. of New York, Buffalo, NY (United States)

    1996-02-01T23:59:59.000Z

    Reactions of metal carbonyl cations (M(CO){sub 6}{sup +}, M = Mn, Re) with hydride-, methide- or halide-containing metal carbonyl anions Fe(CO){sub 4}R{sup -}, R = H, Me; W(CO){sub 5} (CH{sub 3}CN) and W(CO){sub 5}X{sup -}. In contrast, the tungsten hydride and methide complexes react, predominantly, by transfer of the hydride or methide to a carbonyl of the cation at a much faster rate. The iron hydride and methide complexes react by iron-based nucleophilicity involving a two-electron process.

  12. atoms: Topics by E-print Network

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  13. Thermoelectric Generators 1. Thermoelectric generator

    E-Print Network [OSTI]

    Lee, Ho Sung

    1 Thermoelectric Generators HoSung Lee 1. Thermoelectric generator 1.1 Basic Equations In 1821 effects are called the thermoelectric effects. The mechanisms of thermoelectricity were not understood. Cold Hot I - -- - - - - -- Figure 1 Electron concentration in a thermoelectric material. #12;2 A large

  14. A microfabricated atomic clock

    SciTech Connect (OSTI)

    Knappe, Svenja; Shah, Vishal; Schwindt, Peter D.D.; Hollberg, Leo; Kitching, John; Liew, Li-Anne; Moreland, John [Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States); Electromagnetics Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States)

    2004-08-30T23:59:59.000Z

    Fabrication techniques usually applied to microelectromechanical systems (MEMS) are used to reduce the size and operating power of the core physics assembly of an atomic clock. With a volume of 9.5 mm{sup 3}, a fractional frequency instability of 2.5x10{sup -10} at 1 s of integration, and dissipating less than 75 mW of power, the device has the potential to bring atomically precise timing to hand-held, battery-operated devices. In addition, the design and fabrication process allows for wafer-level assembly of the structures, enabling low-cost mass-production of thousands of identical units with the same process sequence, and easy integration with other electronics.

  15. Delay in Atomic Photoionization

    SciTech Connect (OSTI)

    Kheifets, A. S. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030 (United States); Ivanov, I. A. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia)

    2010-12-03T23:59:59.000Z

    We analyze the time delay between emission of photoelectrons from the outer valence ns and np subshells in noble gas atoms following absorption of an attosecond extreme ultraviolet pulse. Various processes such as elastic scattering of the photoelectron on the parent ion and many-electron correlation affect the apparent 'time zero' when the photoelectron leaves the atom. This qualitatively explains the time delay between photoemission from the 2s and 2p subshells of Ne as determined experimentally by attosecond streaking [Science 328, 1658 (2010)]. However, with our extensive numerical modeling, we were only able to account for less than half of the measured time delay of 21{+-}5 as. We argue that the extreme ultraviolet pulse alone cannot produce such a large time delay and it is the streaking IR field that is most likely responsible for this effect.

  16. Effect of Gaseous Impurities on Long-Term Thermal Cycling and Aging Properties of Complex Hydrides for Hydrogen Storage

    SciTech Connect (OSTI)

    Chandra, Dhanesh (Primary Contact); Lamb, Joshua; Chien, Wen-Ming; Talekar, Anjali; and Pal, Narendra.

    2011-03-28T23:59:59.000Z

    This program was dedicated to understanding the effect of impurities on Long-Term Thermal Cycling and aging properties of Complex Hydrides for Hydrogen Storage. At the start of the program we found reversibility between Li2NH+LiH ? LiH+LiNH2 (yielding ~5.8 wt.%H capacity). Then we tested the effect of impurity in H2 gas by pressure cycling at 255oC; first with industrial gas containing ppm levels of O2 and H2O as major impurities. Both these impurities had a significant impact on the reversibility and decreased the capacity by 2.65 wt.%H. Further increase in number of cycles from 500 to 1100 showed only a 0.2 wt%H more weight loss, showing some capacity is still maintained after a significant number of cycles. The loss of capacity is attributed to the formation of ~55 wt% LiH and ~30% Li2O, as major contaminant phases, along with the hydride Li2NH phase; suggesting loss of nitrogen during cycling. The effect of 100 ppm H2O in H2 also showed a decrease of ~2.5 wt.%H (after 560 cycles), and 100ppm O2 in H2; a loss of ~4.1 wt.%. Methane impurity (100 ppm, 100cycles), showed a very small capacity loss of 0.9 wt.%H under similar conditions. However, when Li3N was pressure cycled with 100ppmN2-H2 there were beneficial effects were observed (255oC); the reversible capacity increased to 8.4wt.%H after 853 cycles. Furthermore, with 20 mol.%N2-H2 capacity increased to ~10 wt.%H after 516 cycles. We attribute this enhancement to the reaction of nitrogen with liquid lithium during cycling as the Gibbs free energy of formation of Li3N (?Go = -98.7 kJ/mol) is more negative than that of LiH (?Go = -50.3 kJ/mol). We propose that the mitigation of hydrogen capacity losses is due to the destabilization of the LiH phase that tends to accumulate during cycling. Also more Li2NH phase was found in the cycled product. Mixed Alanates (3LiNH2:Li3AlH6) showed that 7 wt% hydrogen desorbed under dynamic vacuum. Equilibrium experiments (maximum 12 bar H2) showed up to 4wt% hydrogen reversibly stored in the material after the first desorption. The activation energy was found to be 51 kJ/mol, as compared to 81 kJ/mol for pure lithium alanate. It is proposed that based on the data obtained and CALPHAD modeling that the improvement in cycling is due to the formation of pure lithium (liquid at 255oC), which is able to react with nitrogen specifically forming Li3N. The presence of nitrogen in the 80/20 molar mixtures in a hydride bed along with hydrogen causes Li to form Li3N rather than LiH, and subsequently regenerates the Li2NH phase and yields a ~10 wt.%H reversibly.

  17. Hydrogen atom in Palatini theories of gravity

    E-Print Network [OSTI]

    Gonzalo J. Olmo

    2008-06-03T23:59:59.000Z

    We study the effects that the gravitational interaction of $f(R)$ theories of gravity in Palatini formalism has on the stationary states of the Hydrogen atom. We show that the role of gravity in this system is very important for lagrangians $f(R)$ with terms that grow at low curvatures, which have been proposed to explain the accelerated expansion rate of the universe. We find that new gravitationally induced terms in the atomic Hamiltonian generate a strong backreaction that is incompatible with the very existence of bound states. In fact, in the 1/R model, Hydrogen disintegrates in less than two hours. The universe that we observe is, therefore, incompatible with that kind of gravitational interaction. Lagrangians with high curvature corrections do not lead to such instabilities.

  18. Optics and interferometry with atoms and molecules

    E-Print Network [OSTI]

    Cronin, Alexander D.

    Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic ...

  19. Atomic Collapse Observed

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumni AlumniFederalAshley BoyleAn overhead viewAtom-split it

  20. Laser system for secondary cooling of {sup 87}Sr atoms

    SciTech Connect (OSTI)

    Khabarova, K Yu; Slyusarev, S N; Strelkin, S A; Belotelov, G S; Kostin, A S; Pal'chikov, Vitaly G; Kolachevsky, Nikolai N

    2012-11-30T23:59:59.000Z

    A laser system with a narrow generation line for secondary laser cooling of {sup 87}Sr atoms has been developed and investigated. It is planned to use ultracold {sup 87}Sr atoms loaded in an optical lattice in an optical frequency standard. To this end, a 689-nm semiconductor laser has been stabilised using an external reference ultrastable cavity with vibrational and temperature compensation near the critical point. The lasing spectral width was 80 Hz (averaging time 40 ms), and the frequency drift was at a level of 0.3 Hz s{sup -1}. Comparison of two independent laser systems yielded a minimum Allan deviation: 2 Multiplication-Sign 10{sup -14} for 300-s averaging. It is shown that this system satisfies all requirements necessary for secondary cooling of 87Sr atoms using the spectrally narrow {sup 1}S{sub 0} - {sup 3}P{sub 1} transition ({lambda} = 689 nm). (cooling of atoms)

  1. A Single-Photon Server with Just One Atom

    E-Print Network [OSTI]

    Markus Hijlkema; Bernhard Weber; Holger P. Specht; Simon C. Webster; Axel Kuhn; Gerhard Rempe

    2007-02-05T23:59:59.000Z

    Neutral atoms are ideal objects for the deterministic processing of quantum information. Entanglement operations have been performed by photon exchange or controlled collisions. Atom-photon interfaces were realized with single atoms in free space or strongly coupled to an optical cavity. A long standing challenge with neutral atoms, however, is to overcome the limited observation time. Without exception, quantum effects appeared only after ensemble averaging. Here we report on a single-photon source with one-and-only-one atom quasi permanently coupled to a high-finesse cavity. Quasi permanent refers to our ability to keep the atom long enough to, first, quantify the photon-emission statistics and, second, guarantee the subsequent performance as a single-photon server delivering up to 300,000 photons for up to 30 seconds. This is achieved by a unique combination of single-photon generation and atom cooling. Our scheme brings truly deterministic protocols of quantum information science with light and matter within reach.

  2. Atoms.inp Archive: Crystallographic Data from GSECARS

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

    Newville, Matthew

    The Atoms.inp Archive is a collection of crystallographic data for use in XAFS analysis. The crystallographic data is stored as atoms.inp files, which contain all the information necessary to describe the crystal, and can be used by the program ATOMS to generate feff.inp files. These files can then be used by the FEFF program [See http://leonardo.phys.washington.edu/feff/] to calculate a theoretical XAFS spectrum for the crystal. This archive exists because it can take a considerable amount of time to locate a suitable reference for a model structure to use for making theoretical XAFS standards. Even then, references sometimes give non-standard or incomplete crystallographic notation that ATOMS has difficulty interpreting. All of this means that getting a reliable atoms.inp file can take quite a bit of effort. It is hoped that this collection of well-documented and well-tested atoms.inp files will eliminate much of the work in creating theoretical XAFS standards from FEFF. [Taken from http://cars9.uchicago.edu/~newville/adb/]. The collection currently has more than 200 crystal structures, 2748 data files, and it continues to expand. The collection is related to the UWXAFS Project [http://depts.washington.edu/uwxafs/] and to the work of the Consortium for Advanced Radiation Sources (CARS). After searching the Archive, a user may also choose to run the web version of ATOMS software.

  3. Atomic Energy Commission Takes Over Responsibility for all Atomic...

    National Nuclear Security Administration (NNSA)

    Takes Over Responsibility for all Atomic Energy Programs | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

  4. NOx reduction by electron beam-produced nitrogen atom injection

    DOE Patents [OSTI]

    Penetrante, Bernardino M. (San Ramon, CA)

    2002-01-01T23:59:59.000Z

    Deactivated atomic nitrogen generated by an electron beam from a gas stream containing more than 99% N.sub.2 is injected at low temperatures into an engine exhaust to reduce NOx emissions. High NOx reduction efficiency is achieved with compact electron beam devices without use of a catalyst.

  5. Transient x-ray absorption spectroscopy of hydrated halogen atom

    E-Print Network [OSTI]

    Elles, Christopher G.; Shkrob, Ilya A.; Crowell, Robert A.; Arms, Dohn A.; Landahl, Eric C.

    2008-02-11T23:59:59.000Z

    Time-resolved x-ray absorption spectroscopy has been used to observe the transient species generated by one-photon detachment of an electron from aqueous bromide. The K-edge spectrum of the short-lived Br(0) atom exhibits a resonant 1s-4p transition...

  6. A STUDY OF FUNDAMENTAL REACTION PATHWAYS FOR TRANSITION METAL ALKYL COMPLEXES. I. THE REACTION OF A NICKEL METHYL COMPLEX WITH ALKYNES. II. THE MECHANISM OF ALDEHYDE FORMATION IN THE REACTION OF A MOLYBDENUM HYDRIDE WITH MOLYBDENUM ALKYLS

    SciTech Connect (OSTI)

    Huggins, John Mitchell

    1980-06-01T23:59:59.000Z

    I. This study reports the rapid reaction under mild conditions of internal or terminal alkynes with methyl (acetyl~ acetonato) (triphenylphosphine) nickel (1) in either aromatic or ether solvents. In all cases vinylnickel products 2 are formed by insertion of the alkyne into the nickel=methyl bond. These complexes may be converted into a variety of organic products (e.g. alkenes, esters, vinyl halides) by treatment with appropriate reagents. Unsymmetrical alkynes give selectively the one regioisomer with the sterically largest substituent next to the nickel atom. In order to investigate the stereochemistry of the initial insertion, a x-ray diffraction study of the reaction of 1 with diphenylacetylene was carried out. This showed that the vinylnickel complex formed by overall trans insertion was the product of the reaction. Furthermore, subsequent slow isomerization of this complex, to a mixture of it and the corresponding cis isomer, demonstrated that this trans addition product is the kinetic product of the reaction. In studies with other alkynes, the product of trans addition was not always exclusively (or even predominantly) formed, but the ratio of the stereoisomers formed kinetically was substantially different from the thermodynamic ratio. Isotope labeling, added phosphine, and other experiments have allowed us to conclude that the mechanism of this reaction does involve initial cis addition. However, a coordinatively unsaturated vinylnickel complex is initially formed which can undergo rapid, phosphine-catalyzed cis-trans isomerization in competition with its conversion to the isolable phosphine-substituted kinetic reaction products. II. The reaction of CpMo(CO){sub 3}H (1a) with CpMo(CO){sub 3}R (2, R= CH{sub 3}, C{sub 2}H{sub 5}) at 50{degrees} C in THF gives the aldehyde RCHO and the dimers [CpMo(CO){sub 3}]{sub 2} (3a) and [CpMo(CO){sub 2}]{sub 2} (4a). Labeling one of the reactants with a methylcyclopentadienyl ligand it was possible to show that the mixed dimers MeCpMo(CO){sub 3}-(CO){sub 3}MoCp (3b) and MeCpMo(CO){sub 2}{triple_bond}(CO){sub 2}MoCp (4b) are the predominant kinetic products of the reaction. Additionally labeling the carbonyl ligands of 1a with {sup 13}CO led to the conclusion that all three of the carbonyl ligands in 1a end up in the tetracarbonyl dimers 4a if the reaction is carried out under a continuous purge of argon Trapping studies failed to find any evidence for the intermediacy of either [CpMo(CO){sub 3}]{sup -} or [CpMo(CO){sub 3}]{sup +} in this reaction. A mechanism is proposed that involves the initial migration of the alkyl ligand in 2 to CO forming an unsaturated acyl complex which reacts with 1a to give a binuclear complex containing a three center-two electron Mo-H-Mo bond. This complex then selectively looses a carbonyl from the acyl molybdenum, migrates the hydride to that same metal, and forms a metal-metal bond. This binuclear complex with the hydride and acyl ligands on one metal reductively eliminates aldehyde, and migrates a carbonyl ligand, to give 4a directly. The other product 3a is formed by addition of two molecules of free CO to 4a.

  7. Comprehensive online Atomic Database Management System (DBMS) with Highly Qualified Computing Capabilities

    E-Print Network [OSTI]

    Tahat, Amani

    2011-01-01T23:59:59.000Z

    The intensive need of atomic data is expanding continuously in a wide variety of applications (e.g. fusion energy and astrophysics, laser-produced, plasma researches, and plasma processing).This paper will introduce our ongoing research work to build a comprehensive, complete, up-to-date, user friendly and online atomic Database Management System (DBMS) namely called AIMS by using SQLite (http://www.sqlite.org/about.html)(8). Programming language tools and techniques will not be covered here. The system allows the generation of various atomic data based on professional online atomic calculators. The ongoing work is a step forward to bring detailed atomic model accessible to a wide community of laboratory and astrophysical plasma diagnostics. AIMS is a professional worldwide tool for supporting several educational purposes and can be considered as a complementary database of IAEA atomic databases. Moreover, it will be an exceptional strategy of incorporating the output data of several atomic codes to external ...

  8. Quantum transport in ultracold atoms

    E-Print Network [OSTI]

    Chih-Chun Chien; Sebastiano Peotta; Massimiliano Di Ventra

    2015-04-11T23:59:59.000Z

    Ultracold atoms confined by engineered magnetic or optical potentials are ideal systems for studying phenomena otherwise difficult to realize or probe in the solid state because their atomic interaction strength, number of species, density, and geometry can be independently controlled. This review focuses on quantum transport phenomena in atomic gases that mirror and oftentimes either better elucidate or show fundamental differences with those observed in mesoscopic and nanoscopic systems. We discuss significant progress in performing transport experiments in atomic gases, contrast similarities and differences between transport in cold atoms and in condensed matter systems, and survey inspiring theoretical predictions that are difficult to verify in conventional setups. These results further demonstrate the versatility offered by atomic systems in the study of nonequilibrium phenomena and their promise for novel applications.

  9. Experimental Effects of Atomic Oxygen on the Development of an Electric Discharge Oxygen Iodine Laser

    E-Print Network [OSTI]

    Carroll, David L.

    state I. Conventionally, a two-phase (gas-liquid) chemistry singlet oxygen generator (SOG) producesExperimental Effects of Atomic Oxygen on the Development of an Electric Discharge Oxygen Iodine of the electric discharge iodine laser continues, the role of oxygen atoms downstream of the discharge region

  10. Atomic Inference from Weak Gravitational Lensing Data

    SciTech Connect (OSTI)

    Marshall, Phil; /KIPAC, Menlo Park

    2005-12-14T23:59:59.000Z

    We present a novel approach to reconstructing the projected mass distribution from the sparse and noisy weak gravitational lensing shear data. The reconstructions are regularized via the knowledge gained from numerical simulations of clusters, with trial mass distributions constructed from n NFW profile ellipsoidal components. The parameters of these ''atoms'' are distributed a priori as in the simulated clusters. Sampling the mass distributions from the atom parameter probability density function allows estimates of the properties of the mass distribution to be generated, with error bars. The appropriate number of atoms is inferred from the data itself via the Bayesian evidence, and is typically found to be small, reecting the quality of the data. Ensemble average mass maps are found to be robust to the details of the noise realization, and succeed in recovering the demonstration input mass distribution (from a realistic simulated cluster) over a wide range of scales. As an application of such a reliable mapping algorithm, we comment on the residuals of the reconstruction and the implications for predicting convergence and shear at specific points on the sky.

  11. HYDRIDE DEVELOPMENT FOR HYDROGEN STORAGE K. J. Gross, E. Majzoub, G.J. Thomas, and G. Sandrock

    E-Print Network [OSTI]

    of materials have been developed. These are; Generation III and Generation IV Ti-doped sodium alanates requirements needed to supply onboard hydrogen for PEM fuel cell powered vehicles. Two new generations as a function of temperature for both alanate phases Experimental Basics Generation II materials: Crystalline Na

  12. Bogoliubov theory and bosonic atoms

    E-Print Network [OSTI]

    Phan Thanh Nam

    2011-09-13T23:59:59.000Z

    We formulate the Bogoliubov variational principle in a mathematical framework similar to the generalized Hartree-Fock theory. Then we analyze the Bogoliubov theory for bosonic atoms in details. We discuss heuristically why the Bogoliubov energy should give the first correction to the leading energy of large bosonic atoms.

  13. In-situ control system for atomization

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Terpstra, R.L.

    1995-06-13T23:59:59.000Z

    Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray is disclosed. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray. 3 figs.

  14. Spectral Emission of Moving Atom

    E-Print Network [OSTI]

    J. X. Zheng-Johansson

    2008-03-17T23:59:59.000Z

    A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the spectral emission of a moving atom exhibits always a redshift which informs not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a portion of its internal energy on transiting to a lower-energy state which however has in a moving atom an additional energy gain; this results in a redshift in the emission frequency. Based on auxiliary experimental information and a scheme for de Broglie particle formation, we give a vigorous elucidation of the mechanism for deceleration radiation of atomic electron; the corresponding prediction of the redshift is in complete agreement with the Ives and Stilwell's experimental formula.

  15. Supersonic coal water slurry fuel atomizer

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA); Balsavich, John (Foxborough, MA)

    1991-01-01T23:59:59.000Z

    A supersonic coal water slurry atomizer utilizing supersonic gas velocities to atomize coal water slurry is provided wherein atomization occurs externally of the atomizer. The atomizer has a central tube defining a coal water slurry passageway surrounded by an annular sleeve defining an annular passageway for gas. A converging/diverging section is provided for accelerating gas in the annular passageway to supersonic velocities.

  16. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-06-16T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a challenging endeavor. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6$\\,$s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1$\\,$Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based BEC experiments while offering significantly higher repetition rates. Additionally, the flux is approaching those of current interferometers employing Raman-type velocity selection of laser-cooled atoms. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for transportable high-precision quantum sensors.

  17. Atomic cluster state build-up with macroscopic heralding

    SciTech Connect (OSTI)

    Metz, Jeremy; Schoen, Christian [Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BZ (United Kingdom); Beige, Almut [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2007-11-15T23:59:59.000Z

    We describe a measurement-based state preparation scheme for the efficient build-up of cluster states in atom-cavity systems. As in a recent proposal for the generation of maximally entangled atom pairs [Metz et al., Phys. Rev. Lett. 97, 040503 (2006)], we use an electron shelving technique to avoid the necessity for the detection of single photons. Instead, the successful fusion of smaller into larger clusters is heralded by an easy-to-detect macroscopic fluorescence signal. High fidelities are achieved even in the vicinity of the bad cavity limit and are essentially independent of the concrete size of the system parameters.

  18. Generation Planning (pbl/generation)

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.Newof EnergyFundingGene ControlsCounselGeneral User Generation

  19. Detection of transient fluorine atoms

    SciTech Connect (OSTI)

    Loge, G.W.; Nereson, N.; Fry, H.A.

    1986-01-01T23:59:59.000Z

    A KrF eximer laser with a fluence of 50 mJ/cm/sup 2/ was used to photolyze either uranium hexafluoride or molecular fluorine, yielding a transient number density of fluorine atoms. The rise and decay of the atomic fluorine density was observed by transient absorption of a 25-..mu..m Pb-salt diode laser. To prevent the diode laser wavelength from drifting out of resonance with the atomic fluorine line, part of the beam was split off and sent through a microwave discharge fluorine atom cell. This allowed a wavelength modulation-feedback technique to be used to lock the diode laser wavelength onto the atomic line. The remaining diode laser beam was made collinear with the eximer laser beam using a LiF window with a 45/sup 0/ angle of incidence to reflect the infrared beam while transmitting most of the uv beam. Using this setup along with a transient digitizer to average between 100 and 200 transient absorption profiles, fluorine atom number densities on the order of 10/sup 14/ cm/sup -3/ in a 1.7 m pathlength were detected. The signals observed were about a factor of two less than expected from known photolysis and atomic fluorine absorption cross-sections. 2 refs., 4 figs.

  20. Anticipating the atom: popular perceptions of atomic power before Hiroshima

    E-Print Network [OSTI]

    d'Emal, Jacques-Andre Christian

    1994-01-01T23:59:59.000Z

    Before Hiroshima made the Bomb an object of popular concern, possible implications and applications of atomic physics had been discussed in the public forum. The new science of X-rays and radium promised the possibilities of unlimited energy...

  1. atomization atomic absorption: Topics by E-print Network

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

    cells to modern observations of dust clouds in stellar nebulas and Bose-Einstein condensates. Here we show the first absorption imaging of a single atom isolated in vacuum. The...

  2. Chemical factors influencing selenium atomization

    E-Print Network [OSTI]

    Buren, Mary Sue

    1980-01-01T23:59:59.000Z

    Atomization. (August 1980) Mary Sue Buren, B, S. , Angelo State University Chairman of Advisory Comm1ttee: Dr. Thomas M. Vickrey Selenium in an acid1c matrix was analyzed using graphite furnace atom1c absorption with Zeeman-effect background correct1on.... Nickel(II} and lanthanum( III) were introduced as matrix modifiers to determine their effect on interferences 1n selenium atom1zation. In add1tion to matr1x mod1ficat1on, surface coating the graphite furnace with z1rconium and tantalum salts was also...

  3. Chemical factors influencing selenium atomization 

    E-Print Network [OSTI]

    Buren, Mary Sue

    1980-01-01T23:59:59.000Z

    Atomization. (August 1980) Mary Sue Buren, B, S. , Angelo State University Chairman of Advisory Comm1ttee: Dr. Thomas M. Vickrey Selenium in an acid1c matrix was analyzed using graphite furnace atom1c absorption with Zeeman-effect background correct1on.... Nickel(II} and lanthanum( III) were introduced as matrix modifiers to determine their effect on interferences 1n selenium atom1zation. In add1tion to matr1x mod1ficat1on, surface coating the graphite furnace with z1rconium and tantalum salts was also...

  4. Effect of Interatomic Separation on Entanglement Dynamics in a Two-Atom Two-Mode Model

    E-Print Network [OSTI]

    K. Sinha; N. I. Cummings; B. L. Hu

    2011-11-16T23:59:59.000Z

    We analyze the time evolution of quantum entanglement in a model consisting of two two-level atoms interacting with a two-mode electromagnetic field for a variety of initial states and interatomic separations. We study two specific atomic separations which give rise to symmetric atom-field couplings. For general atomic distances we consider a subset of initial states analytically, and then treat the more general situation numerically. We examine a variety of qualitative features such as entanglement sudden death, dynamical generation, protection, and transfer between subsystems. Our analysis shows a stark contrast in features of entanglement between the two special coupling schemes often considered; further, these features are uncharacteristic of those arising for general distances, due to the high degree of symmetry present in the special cases. The variety of behaviors in these two-mode cases suggest the importance of considering atomic separation carefully for any model where two atoms interact with a common field.

  5. Heterogeneous Catalysis on Atomically Dispersed Supported Metals...

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

    Catalysis on Atomically Dispersed Supported Metals: CO2 Reduction on Multifunctional Pd Catalysts. Heterogeneous Catalysis on Atomically Dispersed Supported Metals: CO2 Reduction...

  6. Imaging atoms in 3-D

    ScienceCinema (OSTI)

    Ercius, Peter

    2014-06-27T23:59:59.000Z

    Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

  7. Imaging atoms in 3-D

    SciTech Connect (OSTI)

    Ercius, Peter

    2013-10-31T23:59:59.000Z

    Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

  8. The effect of fluence and irradiation temperature on delayed hydride cracking in Zr-2.5Nb

    SciTech Connect (OSTI)

    Sagat, S.; Coleman, C.E.; Griffiths, M. [AECL Research, Chalk River, Ontario (Canada); Wilkins, B.J.S. [AECL Research, Pinawa, Manitoba (Canada)

    1994-12-31T23:59:59.000Z

    Zirconium alloys are susceptible to a stable cracking process called delayed hydride cracking (DHC). DHC has two stages: (a) crack initiation that requires a minimum crack driving force (the threshold stress intensity factor, K{sub IH}) and (b) stable crack growth that is weakly dependent on K{sub l}. The value of K{sub lH} is an important element in determining the tolerance of components to sharp flaws. The rate of cracking is used in estimating the action time for detecting propagating cracks before they become unstable. Hence, it is important for reactor operators to know how these properties change during service in reactors where the components are exposed to neutron irradiation at elevated temperatures. DHC properties were measured on a number of components, made from the two-phase alloy Zr-2.5 Nb, irradiated at temperatures in the range of 250 to 290 C in fast neutron fluxes (E {>=} 1 MeV) between 1.6 {times} 10{sup 17} and 1.8 {times} 10{sup 18} n/m{sup 2} {center_dot} s to fluences between 0.01 {times} 10{sup 25} and 9.8 {times} 10{sup 25} n/m{sup 2}. The neutron irradiation reduced K{sub IH} by about 20% and increased the velocity of cracking by a factor of about five. The increase in crack velocity was greatest with the lowest irradiation temperature. These changes in the rack velocity by neutron irradiation are explained in terms of the combined effects of irradiation hardening associated with increased -type dislocation density, and {beta}-phase decomposition. While the former process increases crack velocity, the latter process decrease it. The combined contribution is controlled by the irradiation temperature. X-ray diffraction analyses showed that the degree of {beta}-phase decomposition was highest with an irradiation temperature of 290 C while -type dislocation densities were highest with an irradiation temperature of 250 C.

  9. Topological Insulators and Metals in Atomic Optical Lattices

    E-Print Network [OSTI]

    Tudor D. Stanescu; Victor Galitski; J. Y. Vaishnav; Charles W. Clark; S. Das Sarma

    2009-01-26T23:59:59.000Z

    We propose the realization of topological quantum states with cold atoms trapped in an optical lattice. We discuss an experimental setup that generates a two-dimensional hexagonal lattice in the presence of a light-induced periodic vector potential, which represents a realization of the Haldane model with cold atoms. We determine theoretically the conditions necessary for observing the topological states and show that two of the key conditions are: 1) the realization of sharp boundaries and 2) the minimization of any smoothly varying component of the confining potential. We argue that, unlike their condensed matter counterparts, cold atom topological quantum states can be i) "seen", by mapping out the characteristic chiral edge states, and ii) controlled, by controlling the periodic vector potential and the properties of the confining potential.

  10. Cooling atom-cavity systems into entangled states

    E-Print Network [OSTI]

    J. Busch; S. De; S. S. Ivanov; B. T. Torosov; T. P. Spiller; A. Beige

    2011-05-25T23:59:59.000Z

    Generating entanglement by simply cooling a system into a stationary state which is highly entangled has many advantages. Schemes based on this idea are robust against parameter fluctuations, tolerate relatively large spontaneous decay rates, and achieve high fidelities independent of their initial state. A possible implementation of this idea in atom-cavity systems has recently been proposed by Kastoryano et al. [Phys. Rev. Lett. 106, 090502 (2011)]. Here we propose an improved entanglement cooling scheme for two atoms inside an optical cavity which achieves higher fidelities for comparable single-atom cooperativity parameters C. For example, we predict fidelities above 90% even for C as low as 20 without requiring individual laser addressing and without having to detect photons.

  11. The use of zirconium hydride blankets in a minor actinide/thorium burner sodium-cooled reactor for void coefficient control with particular reference to UK's plutonium disposition problem

    E-Print Network [OSTI]

    Arias, Francisco J.; Parks, Geoffrey T.

    2015-04-21T23:59:59.000Z

    The use of zirconium hydride (Th–ZrH1.6) blankets in a thorium-fuelled sodium-cooled reactor for void reactivity control with particular reference to UK's plutonium disposition problem is proposed and considered. It is shown that, with the use...

  12. Recent Progress in ultracold atoms

    E-Print Network [OSTI]

    Baltisberger, Jay H.

    , cold gas experiments 2. How to make a BEC out of fermions 3. Recent Progress: Controlling Interaction (Feshbach Resonance) 4. From BCS to BEC: Rotating trap and spin- polarized condensates. 5. Future research and Einstein What is Bose-Einstein condensation (BEC)? #12;300 K to 1 mK 109 atoms 1 mK to 1 mK 108 106 atoms

  13. Absorption properties of identical atoms

    E-Print Network [OSTI]

    Pedro Sancho

    2013-07-31T23:59:59.000Z

    Emission rates and other optical properties of multiparticle systems in collective and entangled states differ from those in product ones. We show the existence of similar effects in the absorption probabilities for (anti)symmetrized states of two identical atoms. The effects strongly depend on the overlapping between the atoms and differ for bosons and fermions. We propose a viable experimental verification of these ideas.

  14. Light-induced gauge fields for ultracold atoms

    E-Print Network [OSTI]

    N. Goldman; G. Juzeliunas; P. Ohberg; I. B. Spielman

    2014-12-12T23:59:59.000Z

    Gauge fields are central in our modern understanding of physics at all scales. At the highest energy scales known, the microscopic universe is governed by particles interacting with each other through the exchange of gauge bosons. At the largest length scales, our universe is ruled by gravity, whose gauge structure suggests the existence of a particle - the graviton - that mediates the gravitational force. At the mesoscopic scale, solid-state systems are subjected to gauge fields of different nature: materials can be immersed in external electromagnetic fields, but they can also feature emerging gauge fields in their low-energy description. In this review, we focus on another kind of gauge field: those engineered in systems of ultracold neutral atoms. In these setups, atoms are suitably coupled to laser fields that generate effective gauge potentials in their description. Neutral atoms "feeling" laser-induced gauge potentials can potentially mimic the behavior of an electron gas subjected to a magnetic field, but also, the interaction of elementary particles with non-Abelian gauge fields. Here, we review different realized and proposed techniques for creating gauge potentials - both Abelian and non-Abelian - in atomic systems and discuss their implication in the context of quantum simulation. While most of these setups concern the realization of background and classical gauge potentials, we conclude with more exotic proposals where these synthetic fields might be made dynamical, in view of simulating interacting gauge theories with cold atoms.

  15. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-01-02T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for portable high-precision quantum sensors.

  16. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Rudolph, Jan; Grzeschik, Christoph; Sternke, Tammo; Grote, Alexander; Popp, Manuel; Becker, Dennis; Müntinga, Hauke; Ahlers, Holger; Peters, Achim; Lämmerzahl, Claus; Sengstock, Klaus; Gaaloul, Naceur; Ertmer, Wolfgang; Rasel, Ernst M

    2015-01-01T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of...

  17. HRTEM Imaging of Atoms at Sub-Angstrom Resolution

    SciTech Connect (OSTI)

    O'Keefe, Michael A.; Allard, Lawrence F.; Blom, Douglas A.

    2005-04-06T23:59:59.000Z

    John Cowley and his group at Arizona State University pioneered the use of transmission electron microscopy (TEM) for high-resolution imaging. Images were achieved three decades ago showing the crystal unit cell content at better than 4 Angstrom resolution. This achievement enabled researchers to pinpoint the positions of heavy atom columns within the unit cell. Lighter atoms appear as resolution is improved to sub-Angstrom levels. Currently, advanced microscopes can image the columns of the light atoms (carbon, oxygen, nitrogen) that are present in many complex structures, and even the lithium atoms present in some battery materials. Sub-Angstrom imaging, initially achieved by focal-series reconstruction of the specimen exit surface wave, will become common place for next-generation electron microscopes with CS-corrected lenses and monochromated electron beams. Resolution can be quantified in terms of peak separation and inter-peak minimum, but the limits imposed on the attainable resolution by the properties of the micro-scope specimen need to be considered. At extreme resolution the ''size'' of atoms can mean that they will not be resolved even when spaced farther apart than the resolution of the microscope.

  18. Accelerometer using atomic waves for space applications

    E-Print Network [OSTI]

    of Bose-Einstein condensation (BEC) of a dilute gas of trapped atoms in a single quantum state [18, 19, 20 of such devices in the field of navigation, surveying and analysis of earth structures. Matter-wave interferometry that the use of Bose-Einstein condensed atoms will bring the science of atom optics, and in particular atom

  19. Atomic Cascade in Muonic and Hadronic Hydrogen Atoms

    E-Print Network [OSTI]

    T. S. Jensen; V. P. Popov; V. N. Pomerantsev

    2007-12-18T23:59:59.000Z

    The atomic cascade in $\\mu^- p$ and $\\pi^- p$ atoms has been studied with the improved version of the extended cascade model in which new quantum mechanical calculations of the differential and integral cross sections of the elastic scattering, Stark transitions and Coulomb de-excitation have been included for the principal quantum number values $n\\le 8$ and the relative energies $E \\ge 0.01$ eV. The $X$-ray yields and kinetic energy distributions are compared with the experimental data.

  20. Quantum Electrodynamics of Atomic Resonances

    E-Print Network [OSTI]

    Miguel Ballesteros; Jérémy Faupin; Jürg Fröhlich; Baptiste Schubnel

    2015-03-09T23:59:59.000Z

    A simple model of an atom interacting with the quantized electromagnetic field is studied. The atom has a finite mass $m$, finitely many excited states and an electric dipole moment, $\\vec{d}_0 = -\\lambda_{0} \\vec{d}$, where $\\| d^{i}\\| = 1,$ $ i=1,2,3,$ and $\\lambda_0$ is proportional to the elementary electric charge. The interaction of the atom with the radiation field is described with the help of the Ritz Hamiltonian, $-\\vec{d}_0\\cdot \\vec{E}$, where $\\vec{E}$ is the electric field, cut off at large frequencies. A mathematical study of the Lamb shift, the decay channels and the life times of the excited states of the atom is presented. It is rigorously proven that these quantities are analytic functions of the momentum $\\vec{p}$ of the atom and of the coupling constant $\\lambda_0$, provided $|\\vec{p}| < mc$ and $| \\Im\\vec{p} |$ and $| \\lambda_{0} |$ are sufficiently small. The proof relies on a somewhat novel inductive construction involving a sequence of `smooth Feshbach-Schur maps' applied to a complex dilatation of the original Hamiltonian, which yields an algorithm for the calculation of resonance energies that converges super-exponentially fast.

  1. Degeneracy Breaking of Hydrogen Atom

    E-Print Network [OSTI]

    Agung Trisetyarso; Pantur Silaban

    2014-11-21T23:59:59.000Z

    The three dimensional rotation group, SO(3), is a symmetry group of the normal hydrogen atom. Each reducible representation of this group can be associated with a degenerate energy level. If this atom is placed in an external magnetic field, the interaction between the orbital magnetic moment with this field will lead to a symmetry breaking where the symmetry group of the atom is a new group distinct from the SO(3) group. This phenomenon describes the normal Zeeman effect, where a degenerate energy level splits into several new energy levels. It is explicitly shown that each of the new energy levels can be associated with an irreducible representation of the new symmetry group.

  2. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, Cyril V. (Knoxville, TN); Wise, Marcus B. (Kingston, TN)

    1997-01-01T23:59:59.000Z

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid.

  3. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, C.V.; Wise, M.B.

    1997-07-08T23:59:59.000Z

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid. 3 figs.

  4. Regeneration of aluminum hydride

    DOE Patents [OSTI]

    Graetz, Jason Allan (Mastic, NY); Reilly, James J. (Bellport, NY)

    2009-04-21T23:59:59.000Z

    The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

  5. PNNL Chemical Hydride Capabilities

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

    * Quantum chemistry, density functional theory, Car- Parinello, ab initio dynamics, variational transition state theory, molecular dynamics Strategy * Bring some of the...

  6. Regeneration of aluminum hydride

    DOE Patents [OSTI]

    Graetz, Jason Allan; Reilly, James J; Wegrzyn, James E

    2012-09-18T23:59:59.000Z

    The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, and by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

  7. Preparation of Ag Schottky contacts on n-type GaN bulk crystals grown in nitrogen rich atmosphere by the hydride vapor phase epitaxy technique

    SciTech Connect (OSTI)

    Stübner, R., E-mail: ronald.stuebner@physik.tu-dresden.de; Kolkovsky, Vl.; Weber, J. [Technische Universität Dresden, 01062 Dresden (Germany); Leibiger, Gunnar; Habel, Frank [Freiberger Compound Materials GmbH, 09599 Freiberg (Germany)

    2014-10-14T23:59:59.000Z

    Electrical properties of Schottky contacts on n-type GaN grown in nitrogen rich atmosphere with different N/Ga ratios by hydride vapor phase epitaxy were investigated. We show that tunneling of electrons from the conduction band of GaN to the metal is dominant in our samples. The quality of Schottky contacts does not only depend on surface preparation but also on the growth conditions of the crystals. Schottky contacts on these crystals show an increasing deterioration when higher N/Ga growth ratios are used. We correlate our results with the presence of negatively charged gallium vacancies in the samples. These charges compensate the positively charged donors and lead to a significant increase in series resistance.

  8. Understanding and Managing Generation Y

    E-Print Network [OSTI]

    Wallace, Kevin

    2007-12-14T23:59:59.000Z

    There are four generations in the workplace today; they consist of the Silent Generation, Baby Boom Generation, Generation X, and Generation Y. Generation Y, being the newest generation, is the least understood generation although marketers...

  9. Nanoplasmonic Lattices for Ultracold atoms

    E-Print Network [OSTI]

    M. Gullans; T. Tiecke; D. E. Chang; J. Feist; J. D. Thompson; J. I. Cirac; P. Zoller; M. D. Lukin

    2014-07-25T23:59:59.000Z

    We propose to use sub-wavelength confinement of light associated with the near field of plasmonic systems to create nanoscale optical lattices for ultracold atoms. Our approach combines the unique coherence properties of isolated atoms with the sub-wavelength manipulation and strong light-matter interaction associated with nano-plasmonic systems. It allows one to considerably increase the energy scales in the realization of Hubbard models and to engineer effective long-range interactions in coherent and dissipative many-body dynamics. Realistic imperfections and potential applications are discussed.

  10. An ultra-bright atom laser

    E-Print Network [OSTI]

    V. Bolpasi; N. K. Efremidis; M. J. Morrissey; P. Condylis; D. Sahagun; M. Baker; W. von Klitzing

    2013-11-25T23:59:59.000Z

    We present a novel, ultra-bright atom-laser and ultra-cold thermal atom beam. Using rf-radiation we strongly couple the magnetic hyperfine levels of 87Rb atoms in a magnetically trapped Bose-Einstein condensate. At low rf-frequencies gravity opens a small hole in the trapping potenital and a well collimated, extremely bright atom laser emerges from just below the condensate. As opposed to traditional atom lasers based on weak coupling, this technique allows us to outcouple atoms at an arbitrarily large rate. We demonstrate an increase in flux per atom in the BEC by a factor of sixteen compared to the brightest quasi-continuous atom laser. Furthermore, we produce by two orders of magnitude the coldest thermal atom beam to date (200 nK).

  11. Narrowband Biphotons: Generation, Manipulation, and Applications

    E-Print Network [OSTI]

    Chih-Sung Chuu; Shengwang Du

    2015-03-14T23:59:59.000Z

    In this chapter, we review recent advances in generating narrowband biphotons with long coherence time using spontaneous parametric interaction in monolithic cavity with cluster effect as well as in cold atoms with electromagnetically induced transparency. Engineering and manipulating the temporal waveforms of these long biphotons provide efficient means for controlling light-matter quantum interaction at the single-photon level. We also review recent experiments using temporally long biphotons and single photons.

  12. Advancements in Ti Alloy Powder Production by Close-Coupled Gas Atomization

    SciTech Connect (OSTI)

    Heidloff, Andy; Rieken, Joel; Anderson, Iver; Byrd, David

    2011-04-01T23:59:59.000Z

    As the technology for titanium metal injection molding (Ti-MIM) becomes more readily available, efficient Ti alloy fine powder production methods are required. An update on a novel close-coupled gas atomization system has been given. Unique features of the melting apparatus are shown to have measurable effects on the efficiency and ability to fully melt within the induction skull melting system (ISM). The means to initiate the melt flow were also found to be dependent on melt apparatus. Starting oxygen contents of atomization feedstock are suggested based on oxygen pick up during the atomization and MIM processes and compared to a new ASTM specification. Forming of titanium by metal injection molding (Ti-MIM) has been extensively studied with regards to binders, particle shape, and size distribution and suitable de-binding methods have been discovered. As a result, the visibility of Ti-MIM has steadily increased as reviews of technology, acceptability, and availability have been released. In addition, new ASTM specification ASTM F2885-11 for Ti-MIM for biomedical implants was released in early 2011. As the general acceptance of Ti-MIM as a viable fabrication route increases, demand for economical production of high quality Ti alloy powder for the preparation of Ti-MIM feedstock correspondingly increases. The production of spherical powders from the liquid state has required extensive pre-processing into different shapes thereby increasing costs. This has prompted examination of Ti-MIM with non-spherical particle shape. These particles are produced by the hydride/de-hydride process and are equi-axed but fragmented and angular which is less than ideal. Current prices for MIM quality titanium powder range from $40-$220/kg. While it is ideal for the MIM process to utilize spherical powders within the size range of 0.5-20 {mu}m, titanium's high affinity for oxygen to date has prohibited the use of this powder size range. In order to meet oxygen requirements the top size cut has traditionally been 45 {mu}m, and in some instances a bottom cut at +5 {mu}m is made to remove ultra-fine particles and reduce oxygen content. Predictably, use of irregular shaped or larger particle feedstock powder can reduce part quality as sintering shrinkage and part detail suffer. Thus, widespread production and technological use of Ti-MIM is limited due in large part to Ti alloy feedstock cost and availability, not MIM processing capability. Lower cost feedstock of fine, spherical Ti alloy powder with sufficient purity must be available in order to fully utilize the advantages of the Ti-MIM processing route allowing expansion of the market to small complex Ti parts in many high volume applications.

  13. ELECTRONIC SPUTTERING: FROM ATOMIC PHYSICS

    E-Print Network [OSTI]

    Johnson, Robert E.

    ELECTRONIC SPUTTERING: FROM ATOMIC PHYSICS TO CONTINUUM MECHANICS Ejection of simple and complex molecules from surfaces probes the response of condensed matter to electronic excitations and has and Engineering Physics at the University of Virginia, Charlottesville. Bo Sundqvist holds the Chair in Ion

  14. Photoabsorption by Ions and Atoms

    SciTech Connect (OSTI)

    Manson, Steven T. [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)

    2004-12-01T23:59:59.000Z

    Recent progress in theoretical and experimental investigations of photoabsorption by atoms and ions is presented. Specifically, examples of near-chaotic behavior in photoionization of positive ions, low-energy manifestations of nondipole effects, high-energy breakdown of the single particle picture and new phenomenology uncovered in the inner-shell photoabsorption by negative ions are discussed.

  15. Realization of a superconducting atom chip

    E-Print Network [OSTI]

    Thomas Nirrengarten; Angie Qarry; Cédric Roux; Andreas Emmert; Gilles Nogues; Michel Brune; Jean-Michel Raimond; Serge Haroche

    2006-10-09T23:59:59.000Z

    We have trapped rubidium atoms in the magnetic field produced by a superconducting atom chip operated at liquid Helium temperatures. Up to $8.2\\cdot 10^5$ atoms are held in a Ioffe-Pritchard trap at a distance of 440 $\\mu$m from the chip surface, with a temperature of 40 $\\mu$K. The trap lifetime reaches 115 s at low atomic densities. These results open the way to the exploration of atom--surface interactions and coherent atomic transport in a superconducting environment, whose properties are radically different from normal metals at room temperature.

  16. Remote atom entanglement in a fiber-connected three-atom system

    E-Print Network [OSTI]

    Guo Yan-Qing; Chen Jing; Song He-Shan

    2008-05-28T23:59:59.000Z

    An Ising-type atom-atom interaction is obtained in a fiber-connected three-atom system. The interaction is effective when $\\Delta\\approx \\gamma _{0}\\gg g$. The preparations of remote two-atom and three-atom entanglement governed by this interaction are discussed in specific parameters region. The overall two-atom entanglement is very small because of the existence of the third atom. However, the three-atom entanglement can reach a maximum very close to 1.

  17. A solenoidal synthetic field and the non-Abelian Aharonov-Bohm effects in neutral atoms

    E-Print Network [OSTI]

    Ming-Xia Huo; Nie Wei; David A. W. Hutchinson; Leong Chuan Kwek

    2014-08-11T23:59:59.000Z

    Cold neutral atoms provide a versatile and controllable platform for emulating various quantum systems. Despite efforts to develop artificial gauge fields in these systems, realizing a unique ideal-solenoid-shaped magnetic field within the quantum domain in any real-world physical system remains elusive. Here we propose a scheme to generate a "hairline" solenoid with an extremely small size around 1 micrometer which is smaller than the typical coherence length in cold atoms. Correspondingly, interference effects will play a role in transport. Despite the small size, the magnetic flux imposed on the atoms is very large thanks to the very strong field generated inside the solenoid. By arranging different sets of Laguerre-Gauss (LG) lasers, the generation of Abelian and non-Abelian SU(2) lattice gauge fields is proposed for neutral atoms in ring- and square-shaped optical lattices. As an application, interference patterns of the magnetic type-I Aharonov-Bohm (AB) effect are obtained by evolving atoms along a circle over several tens of lattice cells. During the evolution, the quantum coherence is maintained and the atoms are exposed to a large magnetic flux. The scheme requires only standard optical access, and is robust to weak particle interactions.

  18. Gas Diffusion in Metals: Fundamental Study of Helium-Point Defect Interactions in Iron and Kinetics of Hydrogen Desorption from Zirconium Hydride

    E-Print Network [OSTI]

    Hu, Xunxiang

    2013-01-01T23:59:59.000Z

    spallation, fusion and Generation IV fission applications,steels: fusion, and Generation IV fission applications as058101. W.R. Corwin. U.S. Generation IV reactor integrated

  19. Moøller polarimetry with polarized atomic hydrogen at MESA

    SciTech Connect (OSTI)

    Bartolomé, P. Aguar; Aulenbacher, K.; Tyukin, V. [Institut für Kernphysik, Johannes Gutenberg-University, D-55099 Mainz (Germany)

    2013-11-07T23:59:59.000Z

    A new generation of parity violation (PV) electron scattering experiments are planned to be carried out at the Institut für Kernphysik in Mainz. These experiments will be performed at low energies of 100-200 MeV using the new accelerator MESA (Mainz Energy recovering Superconducting Accelerator). One of the main challenges of such experiments is to achieve an accuracy in beam polarization measurements that must be below 0.5%. This very high accuracy can be reached using polarized atomic hydrogen gas, stored in an ultra-cold magnetic trap, as the target for electron beam polarimetry based on Mo/ller scattering. Electron spin-polarized atomic hydrogen can be stored at high densities of 10{sup 16} cm{sup ?2}, over relatively long time periods, in a high magnetic field (8T) and at low temperatures (0.3K). The gradient force splits the ground state of the hydrogen into four states with different energies. Atoms in the low energy states are trapped in the strong magnetic field region whereas the high energy states are repelled and pumped away. The physics of ultra-cold atomic hydrogen in magnetic traps and the status of the Mainz Hydro-Mo/ller project will be presented.

  20. Laser sustained discharge nozzle apparatus for the production of an intense beam of high kinetic energy atomic species

    DOE Patents [OSTI]

    Cross, J.B.; Cremers, D.A.

    1986-01-10T23:59:59.000Z

    Laser sustained discharge apparatus for the production of intense beams of high kinetic energy atomic species is described. A portion of the plasma resulting from a laser sustained continuous optical discharge which generates energetic atomic species from a gaseous source thereof is expanded through a nozzle into a region of low pressure. The expanded plasma contains a significant concentration of the high kinetic energy atomic species which may be used to investigate the interaction of surfaces therewith. In particular, O-atoms having velocities in excess of 3.5 km/s can be generated for the purpose of studying their interaction with materials in order to develop protective materials for spacecraft which are exposed to such energetic O-atoms during operation in low earth orbit.

  1. Role of atomic collisions in fusion

    SciTech Connect (OSTI)

    Post, D.E.

    1982-04-01T23:59:59.000Z

    Atomic physics issues have played a large role in controlled fusion research. A general discussion of the present role of atomic processes in both magnetic and inertial controlled fusion work is presented.

  2. Preliminary steps to the Atomic Energy Commission

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

    program to the newly created Atomic Energy Commission. He had succeeded in ending the war, but the transition to peacetime use of atomic energy was not something the Army was...

  3. atomic kitteni lauljatar: Topics by E-print Network

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  4. atoms barrasiye barhamkoneshhaye: Topics by E-print Network

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  5. atomic mass spectrometry: Topics by E-print Network

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

    Negative *) Atomic composition Graham, Nick 3 Prospects in Analytical Atomic Spectrometry CERN Preprints Summary: Tendencies in five main branches of atomic spectrometry...

  6. Institute for Atom-Efficient Chemical Transformations Energy...

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

    adsorbed in a zirconium oxide nanobowl. The brown atoms are surface oxygen and the coral atoms are zirconium. Carbon, oxygen, and hydrogen atoms of fructose molecules are...

  7. Towards a high-precision atomic gyroscope

    E-Print Network [OSTI]

    Van Camp, Mackenzie A. (Mackenzie Anne)

    2013-01-01T23:59:59.000Z

    In this thesis, I report on the design and construction of the Rubidium Atomic Gyroscope Experiment (RAGE) at Draper Lab.

  8. Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys...

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

    Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction Reaction. Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction...

  9. Generation gaps in engineering?

    E-Print Network [OSTI]

    Kim, David J. (David Jinwoo)

    2008-01-01T23:59:59.000Z

    There is much enthusiastic debate on the topic of generation gaps in the workplace today; what the generational differences are, how to address the apparent challenges, and if the generations themselves are even real. ...

  10. Organolanthanide and organoyttrium hydride chemistry. 6. Direct synthesis and /sup 1/H NMR spectral analysis of the trimetallic yttrium and yttrium-zirconium tetrahydride complexes, (((C/sub 5/H/sub 5/)/sub 2/YH)/sub 3/H)(Li(THF)/sub 4/) and ((CCH/sub 3/C/sub 5/H/sub 4/)/sub 2/YH)/sub 2/((CH/sub 3/C/sub 5/H/sub 4/)/sub 2/ZrH)H)/sup 1/

    SciTech Connect (OSTI)

    Evans, W.J.; Meadows, J.H.; Hanusa, T.P.

    1984-08-08T23:59:59.000Z

    Improved syntheses of several trimetallic tetrahydride complexes (tri(diphenyl lanthanon hydride)-lithium tetrahydrofuran) were studied using lithium hydride, methyl hydride, and tetra-butyl lithium reacted with diphenyl yttrium hydride tetrahydrofuran dimer. The reaction with tetra-butyl lithium yields the trimer as above while the reaction with diphenyl yttrium deuteride tetrahydrofuran with tert-butyl lithium forms a perdeuterio trimer indicating that the tert-butyl group does not provide a negative hydrogen ion for the trimer. Proton NMR spectra of some of the compounds are presented with H-H, Y-H, and Y-Y couplng constants derived from computer simulation of the spectra.

  11. Chaotic Behaviour of Atomic Energy Levels

    E-Print Network [OSTI]

    A. Yilmaz; G. Hacibekiroglu; E. Bolcal; Y. Polatoglu

    2008-04-01T23:59:59.000Z

    The authors of this paper studied Schrodinger wave equation to investiagate the chaotic behavior of atomic energy levels in relation with three quantum numbers n, l, m by means of derived inequality. It could give rise to the siplitting of atomic spectral lines. Keywords: Chaos, Schrodinger wave equation, atomic energy levels

  12. Riso Report No. Danish Atomic Energy Commission

    E-Print Network [OSTI]

    Jagiellonski Institute of Physics Krakow, Poland and P. A. Lindgård Mogensen The Danish Atomic EnergyfM O o 8- OL '·O c/i Riso Report No. Danish Atomic Energy Commission Research Establishment Riso/t on exchangefrom: Library, Danish Atomic Energy Commission, Risd, Roskilde, Denmark #12;May, 1966 Ris6 Report No

  13. The Future of Atomic Energy

    DOE R&D Accomplishments [OSTI]

    Fermi, E.

    1946-05-27T23:59:59.000Z

    There is definitely a technical possibility that atomic power may gradually develop into one of the principal sources of useful power. If this expectation will prove correct, great advantages can be expected to come from the fact that the weight of the fuel is almost negligible. This feature may be particularly valuable for making power available to regions of difficult access and far from deposits of coal. It also may prove a great asset in mobile power units for example in a power plant for ship propulsion. On the negative side there are some technical limitations to be applicability of atomic power of which perhaps the most serious is the impossibility of constructing light power units; also there will be some peculiar difficulties in operating atomic plants, as for example the necessity of handling highly radioactive substances which will necessitate, at least for some considerable period, the use of specially skilled personnel for the operation. But the chief obstacle in the way of developing atomic power will be the difficulty of organizing a large scale industrial development in an internationally safe way. This presents actually problems much more difficult to solve than any of the technical developments that are necessary, It will require an unusual amount of statesmanship to balance properly the necessity of allaying the international suspicion that arises from withholding technical secrets against the obvious danger of dumping the details of the procedures for an extremely dangerous new method of warfare on a world that may not yet be prepared to renounce war. Furthermore, the proper balance should be found in the relatively short time that will elapse before the 'secrets' will naturally become open knowledge by rediscovery on part of the scientists and engineers of other countries.

  14. Small Generator Aggregation (Maine)

    Broader source: Energy.gov [DOE]

    This section establishes requirements for electricity providers to purchase electricity from small generators, with the goal of ensuring that small electricity generators (those with a nameplate...

  15. NAAP Hydrogen Atom 1/9 The Hydrogen Atom Student Guide

    E-Print Network [OSTI]

    Farritor, Shane

    Name: NAAP ­ Hydrogen Atom 1/9 The Hydrogen Atom ­ Student Guide Background Material Carefully read and the Quantum model represent the Hydrogen atom. In some cases they both describe things in the same way frequency, smaller energy, and the same velocity through space as a blue photon". #12;NAAP ­Hydrogen Atom 2

  16. Fast transport, atom sample splitting and single-atom qubit supply in two-dimensional arrays

    E-Print Network [OSTI]

    Birkl, Gerhard

    Fast transport, atom sample splitting and single-atom qubit supply in two-dimensional arrays architecture for neutral atom quantum information processing, quantum simulation and the manipulation of ultra-cold implemented functions. We introduce piezo-actuator-based transport of atom ensembles over distances of more

  17. Light pulse in {Lambda}-type cold-atom gases

    SciTech Connect (OSTI)

    Wei Ran; Deng Youjin; Chen Shuai; Chen Zengbing; Pan Jianwei [Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Zhao Bo [Institute for Theoretical physics, University of Innsbruck, A-6020 Innsbruck (Austria); Institute for Quantum Optics and Quantum Information of the Austrian Academy of Science, A-6020 Innsbruck (Austria)

    2010-04-15T23:59:59.000Z

    We investigate the behavior of the light pulse in {Lambda}-type cold-atom gases with two counter-propagating control lights with equal strength by directly simulating the dynamic equations and exploring the dispersion relation. Our analysis shows that, depending on the length L{sub 0} of the stored wave packet and the decay rate {gamma} of ground-spin coherence, the recreated light can behave differently. For long L{sub 0} and/or large {gamma}, a stationary light pulse is produced, while two propagating light pulses appear for short L{sub 0} and/or small {gamma}. In the {gamma}{yields}0 limit, the light always splits into two propagating pulses for a sufficiently long time. This scenario agrees with a recent experiment [Y.-W. Lin et al., Phys. Rev. Lett. 102, 213601 (2009)] where two propagating light pulses are generated in laser-cooled cold-atom ensembles.

  18. Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel

    SciTech Connect (OSTI)

    John D. Bess; Thomas L. Maddock; Margaret A. Marshall; Leland M. Montierth

    2011-03-01T23:59:59.000Z

    The neutron radiography (NRAD) reactor is a 250 kW TRIGA® (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The 60-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has been evaluated as an acceptable benchmark experiment. The initial critical configuration developed during the fuel loading process, which contains only 56 fuel elements, has not been evaluated as it is very similar to the evaluated core configuration. The benchmark eigenvalue is 1.0012 ± 0.0029. Calculated eigenvalues differ significantly (~±1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

  19. Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel

    SciTech Connect (OSTI)

    John D. Bess; Thomas L. Maddock; Margaret A. Marshall; Leland M. Montierth

    2014-03-01T23:59:59.000Z

    The neutron radiography (NRAD) reactor is a 250 kW TRIGA® (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The 60-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has been evaluated as an acceptable benchmark experiment. The initial critical configuration developed during the fuel loading process, which contains only 56 fuel elements, has not been evaluated as it is very similar to the evaluated core configuration. The benchmark eigenvalue is 1.0012 ± 0.0029. Calculated eigenvalues differ significantly (~±1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

  20. Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel

    SciTech Connect (OSTI)

    John D. Bess; Thomas L. Maddock; Margaret A. Marshall; Leland M. Montierth

    2013-03-01T23:59:59.000Z

    The neutron radiography (NRAD) reactor is a 250 kW TRIGA® (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The initial critical configuration developed during the fuel loading process, which contains only 56 fuel elements, has been evaluated as an acceptable benchmark experiment. The 60-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has also been evaluated as an acceptable benchmark experiment. Calculated eigenvalues differ significantly (~±1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

  1. Ultracold Atoms: How Quantum Field Theory Invaded Atomic Physics

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank CasellaEnergyUltracold Atoms: How Quantum

  2. Engineering Atomic Quantum Reservoirs for Photons

    E-Print Network [OSTI]

    Susanne Pielawa; Luiz Davidovich; David Vitali; Giovanna Morigi

    2010-04-06T23:59:59.000Z

    We present protocols for creating entangled states of two modes of the electromagnetic field, by using a beam of atoms crossing microwave resonators. The atoms are driven by a transverse, classical field and pump correlated photons into (i) two modes of a cavity and (ii) the modes of two distant cavities. The protocols are based on a stochastic dynamics, characterized by random arrival times of the atoms and by random interaction times between atoms and cavity modes. The resulting effective model yields a master equation, whose steady state is an entangled state of the cavity modes. In this respect, the atoms act like a quantum reservoir, pulling the cavity modes into an entangled, Einstein-Podolski-Rosen (EPR) state, whose degree of entanglement is controlled by the intensity and the frequency of the transverse field. This scheme is robust against stochastic fluctuations in the atomic beam, and it does not require atomic detection nor velocity selection.

  3. Engineering Atomic Quantum Reservoirs for Photons

    E-Print Network [OSTI]

    Pielawa, Susanne; Vitali, David; Morigi, Giovanna

    2010-01-01T23:59:59.000Z

    We present protocols for creating entangled states of two modes of the electromagnetic field, by using a beam of atoms crossing microwave resonators. The atoms are driven by a transverse, classical field and pump correlated photons into (i) two modes of a cavity and (ii) the modes of two distant cavities. The protocols are based on a stochastic dynamics, characterized by random arrival times of the atoms and by random interaction times between atoms and cavity modes. The resulting effective model yields a master equation, whose steady state is an entangled state of the cavity modes. In this respect, the atoms act like a quantum reservoir, pulling the cavity modes into an entangled, Einstein-Podolski-Rosen (EPR) state, whose degree of entanglement is controlled by the intensity and the frequency of the transverse field. This scheme is robust against stochastic fluctuations in the atomic beam, and it does not require atomic detection nor velocity selection.

  4. atomic recoil laser: Topics by E-print Network

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

    Atomic Recoil Laser Quantum Physics (arXiv) Summary: We formulate a wave atom optics theory of the Collective Atomic Recoil Laser, where the atomic center-of-mass motion...

  5. Design of a dual species atom interferometer for space

    E-Print Network [OSTI]

    Thilo Schuldt; Christian Schubert; Markus Krutzik; Lluis Gesa Bote; Naceur Gaaloul; Jonas Hartwig; Holger Ahlers; Waldemar Herr; Katerine Posso-Trujillo; Jan Rudolph; Stephan Seidel; Thijs Wendrich; Wolfgang Ertmer; Sven Herrmann; André Kubelka-Lange; Alexander Milke; Benny Rievers; Emanuele Rocco; Andrew Hinton; Kai Bongs; Markus Oswald; Matthias Franz; Matthias Hauth; Achim Peters; Ahmad Bawamia; Andreas Wicht; Baptiste Battelier; Andrea Bertoldi; Philippe Bouyer; Arnaud Landragin; Didier Massonnet; Thomas Lévèque; Andre Wenzlawski; Ortwin Hellmig; Patrick Windpassinger; Klaus Sengstock; Wolf von Klitzing; Chris Chaloner; David Summers; Philip Ireland; Ignacio Mateos; Carlos F. Sopuerta; Fiodor Sorrentino; Guglielmo M. Tino; Michael Williams; Christian Trenkel; Domenico Gerardi; Michael Chwalla; Johannes Burkhardt; Ulrich Johann; Astrid Heske; Eric Wille; Martin Gehler; Luigi Cacciapuoti; Norman Gürlebeck; Claus Braxmaier; Ernst Rasel

    2014-12-08T23:59:59.000Z

    Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry, the detection unit, the vacuum system for $10^{-11}$ mbar ultra-high vacuum generation, and the high-suppression factor magnetic shielding as well as the thermal control system. The laser system is based on a hybrid approach using fiber-based telecom components and high-power laser diode technology and includes all laser sources for 2D-MOT, 3D-MOT, ODT, interferometry and detection. Manipulation and switching of the laser beams is carried out on an optical bench using Zerodur bonding technology. The instrument consists of 9 units with an overall mass of 221 kg, an average power consumption of 608 W (819 W peak), and a volume of 470 liters which would well fit on a satellite to be launched with a Soyuz rocket, as system studies have shown.

  6. Generation to Generation: The Heart of Family Medicine

    E-Print Network [OSTI]

    Winter, Robin O

    2012-01-01T23:59:59.000Z

    Ageism in the Workplace. Generations Spring, 5. Westman,of caring for multiple generations simultaneously. StronglyGeneration to Generation: The Heart of Family Medicine

  7. Gamma ray generator

    DOE Patents [OSTI]

    Firestone, Richard B; Reijonen, Jani

    2014-05-27T23:59:59.000Z

    An embodiment of a gamma ray generator includes a neutron generator and a moderator. The moderator is coupled to the neutron generator. The moderator includes a neutron capture material. In operation, the neutron generator produces neutrons and the neutron capture material captures at least some of the neutrons to produces gamma rays. An application of the gamma ray generator is as a source of gamma rays for calibration of gamma ray detectors.

  8. Atomic Structure Calculations from the Los Alamos Atomic Physics Codes

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

    Cowan, R. D.

    The well known Hartree-Fock method of R.D. Cowan, developed at Los Alamos National Laboratory, is used for the atomic structure calculations. Electron impact excitation cross sections are calculated using either the distorted wave approximation (DWA) or the first order many body theory (FOMBT). Electron impact ionization cross sections can be calculated using the scaled hydrogenic method developed by Sampson and co-workers, the binary encounter method or the distorted wave method. Photoionization cross sections and, where appropriate, autoionizations are also calculated. Original manuals for the atomic structure code, the collisional excitation code, and the ionization code, are available from this website. Using the specialized interface, you will be able to define the ionization stage of an element and pick the initial and final configurations. You will be led through a series of web pages ending with a display of results in the form of cross sections, collision strengths or rates coefficients. Results are available in tabular and graphic form.

  9. General Atomics | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdf Jump1946865°,Park, Texas:Webinars/Puesta en Marcha,Geary,GenSelfandAtomics

  10. Atoms can be divided into three categories: polar, non-polar and hydrogen atom

    E-Print Network [OSTI]

    Pei-Lin You

    2010-10-10T23:59:59.000Z

    Since the time of Rutherford 1911) physicists and chemists commonly believed that with no electric field, the nucleus of an atom is at the centre of the electron cloud, atoms do not have permanent electric dipole moment (EDM), so that there is no polar atom in nature. In the fact, the idea is untested hypothesis. After ten years of intense research, our experiments showed that atoms can be divided into three categories: polar, non-polar and hydrogen atom. Alkali atoms are all polar atoms. The EDM of a Sodium, Potassium, Rubidium and Cesium atom in the ground state have been obtained as follows: d(Na)=1.28*10 to-8 power e.cm; d(K)=1.58*10 to-8 power e.cm; d(Rb)=1.70 *10 to-8 power e.cm; d(Cs)=1.86*10 to-8 power e.cm. All kind of atoms are non-polar atoms except for alkali and hydrogen atoms. Hydrogen atom is quite distinct from the others. The ground state in hydrogen is non-polar atom(d=0) but the excited state is polar atom, for example, the first excited state has a large EDM: d(H)=3ea=1.59*10 to-8 power e.cm (a is Bohr radius).

  11. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    2008-04-22T23:59:59.000Z

    A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

  12. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    2009-12-29T23:59:59.000Z

    A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

  13. Cylindrical neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2005-06-14T23:59:59.000Z

    A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

  14. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C.; Wang, Chengpu

    2006-08-22T23:59:59.000Z

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  15. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V.; Wang, Chengpu

    2004-11-16T23:59:59.000Z

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  16. Hydrogen Atom in Relativistic Motion

    E-Print Network [OSTI]

    M. Jarvinen

    2005-04-11T23:59:59.000Z

    The Lorentz contraction of bound states in field theory is often appealed to in qualitative descriptions of high energy particle collisions. Surprisingly, the contraction has not been demonstrated explicitly even in simple cases such as the hydrogen atom. It requires a calculation of wave functions evaluated at equal (ordinary) time for bound states in motion. Such wave functions are not obtained by kinematic boosts from the rest frame. Starting from the exact Bethe-Salpeter equation we derive the equal-time wave function of a fermion-antifermion bound state in QED, i.e., positronium or the hydrogen atom, in any frame to leading order in alpha. We show explicitly that the bound state energy transforms as the fourth component of a vector and that the wave function of the fermion-antifermion Fock state contracts as expected. Transverse photon exchange contributes at leading order to the binding energy of the bound state in motion. We study the general features of the corresponding fermion-antifermion-photon Fock states, and show that they do not transform by simply contracting. We verify that the wave function reduces to the light-front one in the infinite momentum frame.

  17. ICPIG, July 15-20, 2007, Prague, Czech Republic C9 Heavy particle impact excitation of atomic oxygen in front of the powered

    E-Print Network [OSTI]

    Fehske, Holger

    was assumed. Collision between O2 + and the background gas O2 generate electronically excited atomic oxygen oxygen in front of the powered electrode of oxygen rf plasmas ­ Experiment and PIC-Simulation K. Dittmann) resolved plasma induced optical emission of the atomic oxygen in an asymmetrical oxygen rf plasma (CCP

  18. Phases of Atom-Molecule Vortex Matter

    SciTech Connect (OSTI)

    Woo, S. J.; Bigelow, N. P. [Department of Physics and Astronomy, University of Rochester, Rochester, New York (United States); Park, Q-Han [Department of Physics, Korea University, Seoul (Korea, Republic of)

    2008-03-28T23:59:59.000Z

    We study ground state vortex configurations in a rotating atom-molecule Bose-Einstein condensate. It is found that the coherent coupling between the atomic and molecular condensates can render a pairing of atomic and molecular vortices into a composite structure that resembles a carbon dioxide molecule. Structural phase transitions of vortex lattices are also explored through different physical parameters including the rotational frequency of the system.

  19. Method for enhanced atomization of liquids

    DOE Patents [OSTI]

    Thompson, Richard E. (27121 Puerta del Oro, Mission Viejo, CA 92691); White, Jerome R. (44755 Wyandotte, Hemet, CA 92544)

    1993-01-01T23:59:59.000Z

    In a process for atomizing a slurry or liquid process stream in which a slurry or liquid is passed through a nozzle to provide a primary atomized process stream, an improvement which comprises subjecting the liquid or slurry process stream to microwave energy as the liquid or slurry process stream exits the nozzle, wherein sufficient microwave heating is provided to flash vaporize the primary atomized process stream.

  20. Collective Atomic Recoil Laser as a synchronization transition

    E-Print Network [OSTI]

    J. Javaloyes; M. Perrin; A. Politi

    2007-12-11T23:59:59.000Z

    We consider here a model previously introduced to describe the collective behavior of an ensemble of cold atoms interacting with a coherent electromagnetic field. The atomic motion along the self-generated spatially-periodic force field can be interpreted as the rotation of a phase oscillator. This suggests a relationship with synchronization transitions occurring in globally coupled rotators. In fact, we show that whenever the field dynamics can be adiabatically eliminated, the model reduces to a self-consistent equation for the probability distribution of the atomic "phases". In this limit, there exists a formal equivalence with the Kuramoto model, though with important differences in the self-consistency conditions. Depending on the field-cavity detuning, we show that the onset of synchronized behavior may occur through either a first- or second-order phase transition. Furthermore, we find a secondary threshold, above which a periodic self-pulsing regime sets in, that is immediately followed by the unlocking of the forward-field frequency. At yet higher, but still experimentally meaningful, input intensities, irregular, chaotic oscillations may eventually appear. Finally, we derive a simpler model, involving only five scalar variables, which is able to reproduce the entire phenomenology exhibited by the original model.

  1. CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT

    Office of Legacy Management (LM)

    Westinghouse Atomic 1 U.S. Department of Energy Interim Residual Contamination and Waste Control Guidelines for bormerly Utilized Sites Remedial Action Program (FUSRAP) d Remote...

  2. Atomic 'mismatch' creates nano 'dumbbells' | Argonne National...

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

    Atomic 'mismatch' creates nano 'dumbbells' By Jared Sagoff * December 4, 2014 Tweet EmailPrint ARGONNE, Ill. - Like snowflakes, nanoparticles come in a wide variety of shapes and...

  3. Atomic Energy and Nuclear Materials Program (Tennessee)

    Broader source: Energy.gov [DOE]

    The Atomic Energy and Nuclear Materials section of the Tennessee Code covers all of the regulations, licenses, permits, siting requirements, and practices relevant to a nuclear energy development. ...

  4. Classical and Quantum Chaos in Atom Optics

    E-Print Network [OSTI]

    Farhan Saif

    2006-04-10T23:59:59.000Z

    The interaction of an atom with an electromagnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electromagnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits dynamical localization and quantum recurrences.

  5. United States Atomic Energy Commission formed

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

    weapons problem, the United States worked to establish its own formal organization. The transition from military civilian control of nuclear energy was defined in the Atomic...

  6. Distribution Category: Atomic, Molecular, and Chemical Physics

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

    Atomic, Molecular, and Chemical Physics (UC-411) ARGONNE NATIONAL LABORATORY 9700 South Cass Avenue Argonne, TIlinois 60439 ANLI APSILS-151 RESULTS OF DESIGN CALCULATIONS FOR THE...

  7. Remote preparation of an atomic quantum memory

    E-Print Network [OSTI]

    Wenjamin Rosenfeld; Stefan Berner; Juergen Volz; Markus Weber; Harald Weinfurter

    2006-08-29T23:59:59.000Z

    Storage and distribution of quantum information are key elements of quantum information processing and quantum communication. Here, using atom-photon entanglement as the main physical resource, we experimentally demonstrate the preparation of a distant atomic quantum memory. Applying a quantum teleportation protocol on a locally prepared state of a photonic qubit, we realized this so-called remote state preparation on a single, optically trapped 87Rb atom. We evaluated the performance of this scheme by the full tomography of the prepared atomic state, reaching an average fidelity of 82%.

  8. Gas Atomization of Stainless Steel - Slow Motion

    SciTech Connect (OSTI)

    None

    2011-01-01T23:59:59.000Z

    Stainless steel liquid atomized by supersonic argon gas into a spray of droplets at ~1800ºC. Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a black and white high speed video of a liquid metal stream being atomized by high pressure gas. This material was atomized at the Ames Laboratory's Materials Preparation Center http://www.mpc.ameslab.gov

  9. Subwavelength Transportation of Light with Atomic Resonances

    E-Print Network [OSTI]

    Chui, Siu-Tat; Jo, Gyu-Boong

    2015-01-01T23:59:59.000Z

    We propose and investigate a new type of optical waveguide made by an array of atoms without involving conventional Bragg scattering or total internal reflection. A finite chain of atoms collectively coupled through their intrinsic resonance supports a propagating mode with minimal radiative loss when the array spacing $a$ is around 0.6$\\lambda_0/2\\pi$ where $\\lambda_0$ is the wavelength of the nearly resonant optical transition. We find that the transportation is robust with respect to position fluctuation and remains possible when the atoms are placed on a circle. Our result paves the way to implement the subwavelength transportation of light in integrated optical circuits with cold atoms.

  10. New wave generation

    E-Print Network [OSTI]

    Mercier, Matthieu J.

    We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (Exp. Fluids, vol. 42, 2007, pp. 123–130). This ...

  11. CARBON ATOM DISTRIBUTION IN A DUAL PHASE STEEL: AN ATOM PROBE STUDY

    E-Print Network [OSTI]

    Barnard, S.J.

    2014-01-01T23:59:59.000Z

    ATOM DISTRIBUTION IN A DUAL PHASE STEEL: AN ATOM PROBE STUDY~4720 1 U.S.A. IntroductioE. Dual Phase steels are currentlymartensite-austenite dual phase steel, although the results

  12. Vibrational Modes of Adsorbed Atoms

    E-Print Network [OSTI]

    LAWRENCE, WR; Allen, Roland E.

    1977-01-01T23:59:59.000Z

    of adsorbed atoms. vi rational modes *Present address: S h University of H c ool of Scienc City, Tex. ouston at Clear La ', r e e and Technology Lake City, Clea Lak %. R. wrence and R. E. Allen published). Allen, Phys. Rev. B (to be 2G. P... are about t r Ne on Kr. The d ou he same as fo mode labeled 2V a as large in the f' t X is almost erst (adsorbate) la e od( b t t)l pure surface mod e ayer. The 1H mode at X is a 4, this mode bec m e. Just to the r'right of X in Fig. e ecomes a...

  13. Multimode Raman light-atom interface in warm atomic ensemble as multiple three-mode quantum operations

    E-Print Network [OSTI]

    Parniak, Micha?; Wasilewski, Wojciech

    2015-01-01T23:59:59.000Z

    We analyze the properties of a Raman quantum light-atom interface in long atomic ensemble and its applications as a quantum memory or two-mode squeezed state generator. We include both Stokes and anti-Stokes scattering and the effects of Doppler broadening in buffer gas assuming frequent velocity-averaging collisions. We find the Green functions describing multimode transformation from input to output fields of photons and atomic excitations. Proper mode basis is found via singular value decomposition. It reveals that triples of modes are coupled by a transformation equivalent to a combination of two beamsplitters and a two-mode squeezing operation. We analyze the possible transformations on an example of warm rubidium-87 vapor. We find that the fidelity of the mapping of a single excitation between the memory and light is strictly limited by the fractional contribution of the Stokes scattering in predominantly anti-Stokes process. The model we present bridges the gap between the Stokes only and anti-Stokes o...

  14. Motor/generator

    DOE Patents [OSTI]

    Hickam, Christopher Dale (Glasford, IL)

    2008-05-13T23:59:59.000Z

    A motor/generator is provided for connecting between a transmission input shaft and an output shaft of a prime mover. The motor/generator may include a motor/generator housing, a stator mounted to the motor/generator housing, a rotor mounted at least partially within the motor/generator housing and rotatable about a rotor rotation axis, and a transmission-shaft coupler drivingly coupled to the rotor. The transmission-shaft coupler may include a clamp, which may include a base attached to the rotor and a plurality of adjustable jaws.

  15. Creating a Cognitive Agent in a Virtual World: Planning, Navigation, and Natural Language Generation

    E-Print Network [OSTI]

    Hewlett, William

    2013-01-01T23:59:59.000Z

    Generation . . . . . . . . . . . . . . . . . . . . .Language Generation . . . . . . . . . . . . . . . . .Language Generation . . . . . . . . . . . . . . . . . . . .

  16. Relativistic atomic physics at the SSC

    SciTech Connect (OSTI)

    NONE

    1990-12-31T23:59:59.000Z

    This report discusses the following proposed work for relativistic atomic physics at the Superconducting Super Collider: Beam diagnostics; atomic physics research; staffing; education; budget information; statement concerning matching funds; description and justification of major items of equipment; statement of current and pending support; and assurance of compliance.

  17. Atomic processes in high-density plasmas

    SciTech Connect (OSTI)

    More, R.M.

    1982-12-21T23:59:59.000Z

    This review covers dense atomic plasmas such as that produced in inertial confinement fusion. The target implosion physics along with the associated atomic physics, i.e., free electron collision phenomena, electron states I, electron states II, and nonequilibrium plasma states are described. (MOW)

  18. Interaction of trapped ions with trapped atoms

    E-Print Network [OSTI]

    Grier, Andrew T. (Andrew Todd)

    2011-01-01T23:59:59.000Z

    In this thesis, I present results from two Paul-trap based ion traps carried out in the Vuleti? laboratory: the Atom-Ion trap for collision studies between cold atoms and cold ions, and the Cavity-Array trap for studying ...

  19. Photoassociative molecular spectroscopy for atomic radiative lifetimes.

    E-Print Network [OSTI]

    Boyer, Edmond

    very far apart, in so-called long- range molecular states, their mutual interaction is ruled by plain atomic properties. The high- resolution spectroscopic study of some molecular excited states populated by photoassociation of cold atoms (photoassociative spectroscopy) gives a good illustration of this property

  20. Sagnac interferometry with a single atomic clock

    E-Print Network [OSTI]

    Stevenson, R; Bishop, T; Lesanovsky, I; Fernholz, T

    2015-01-01T23:59:59.000Z

    We theoretically discuss an implementation of a Sagnac interferometer with cold atoms. In contrast to currently existing schemes our protocol does not rely on any free propagation of atoms. Instead it is based on superpositions of fully confined atoms and state-dependent transport along a closed path. Using Ramsey sequences for an atomic clock, the accumulated Sagnac phase is encoded in the resulting population imbalance between two internal (clock) states. Using minimal models for the above protocol we analytically quantify limitations arising from atomic dynamics and finite temperature. We discuss an actual implementation of the interferometer with adiabatic radio-frequency potentials that is inherently robust against common mode noise as well as phase noise from the reference oscillator.

  1. Sagnac interferometry with a single atomic clock

    E-Print Network [OSTI]

    R. Stevenson; M. Hush; T. Bishop; I. Lesanovsky; T. Fernholz

    2015-04-21T23:59:59.000Z

    We theoretically discuss an implementation of a Sagnac interferometer with cold atoms. In contrast to currently existing schemes our protocol does not rely on any free propagation of atoms. Instead it is based on superpositions of fully confined atoms and state-dependent transport along a closed path. Using Ramsey sequences for an atomic clock, the accumulated Sagnac phase is encoded in the resulting population imbalance between two internal (clock) states. Using minimal models for the above protocol we analytically quantify limitations arising from atomic dynamics and finite temperature. We discuss an actual implementation of the interferometer with adiabatic radio-frequency potentials that is inherently robust against common mode noise as well as phase noise from the reference oscillator.

  2. Electronic structures of transition metal to hydrogen bonds: oxidative addition of dihydrogen to a square planar rhodium complex and quantum mechanical prediction of the geometry of a metal hydride

    E-Print Network [OSTI]

    Halpin, Carolyn F.

    1986-01-01T23:59:59.000Z

    and applications is dihydrogen or molecular hydrogen. Both the Heber process, in which nitrogen is converted to ammonia on an iron catalyst, and the Fischer-Tropsch synthesis, in which carbon monoxide is converted to hydrocarbons over iron and cobalt catalysts... systems containing hydride ligands. This work presents a computational method for examining the energetics and structures of two systems. The reaction RhC1(CO)(PHs)z + Hz ~ (H)zRhC1(CO)(PHs)z was examined to a~plain why the oxidation of RhCI(CO...

  3. On the energy of electric field in hydrogen atom

    E-Print Network [OSTI]

    Yuri Kornyushin

    2009-07-30T23:59:59.000Z

    It is shown that hydrogen atom is a unique object in physics having negative energy of electric field, which is present in the atom. This refers also to some hydrogen-type atoms: hydrogen anti-atom, atom composed of proton and antiproton, and positronium.

  4. Laser trapping of {sup 21}Na atoms

    SciTech Connect (OSTI)

    Lu, Zheng-Tian

    1994-09-01T23:59:59.000Z

    This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, {sup 21}Na atoms were produced by bombarding {sup 24}Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The {sup 21}Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.

  5. Spectral and temporal structures of high-order harmonic generation of Na in intense mid-ir laser fields

    E-Print Network [OSTI]

    Chu, Shih-I

    and efficient propagation of the wave function in space and time. Excellent agreement of the HHG spectrum into different HHG mechanisms in different energy regimes of Na atoms at long wavelengths. DOI: 10.1103/Phys,2 . The generation of har- monics in rare-gas atoms that extend up to orders of about 300 well within the water

  6. Coherence Induced by Incoherent Pumping Field and Decay Process in Three-level $?$ Type Atomic System

    E-Print Network [OSTI]

    Bao-Quan Ou; Lin-Mei Liang; Cheng-Zu Li

    2007-12-25T23:59:59.000Z

    Following the method of Victor V. Kozlov et al.[PhysRevA. 74. 063829],we inspect the coherence induced by incoherent pump and spontaneous decay process in $\\Lambda$ type three-level atomic system with degenerated lower duplicate levels. The system shows a coherent population trapping state and multi-steady states characteristic in different conditions. Interestingly, two kinds of steady states generated by the system in different sets of pumping and decaying parameters, the "singlet" state and the "triplet" state, exhibit stable or unstable characteristics under the action of pumping field and vacuum reservoir, which promise fruitful applications to atomic coherence and interference in quantum optics.

  7. Engineering an atom-interferometer with modulated light-induced $3 \\pi$ spin-orbit coupling

    E-Print Network [OSTI]

    Olson, Abraham J; Blasing, David B; Niffenegger, Robert J; Chen, Yong P

    2015-01-01T23:59:59.000Z

    We have developed an experimental method to modify the single-particle dispersion using periodic modulation of Raman beams which couple two spin-states of an ultracold atomic gas. The modulation introduces a new coupling between Raman-induced spin-orbit-coupled dressed bands, creating a second generation of dressed-state eigenlevels that feature both a novel 3{\\pi} spin-orbit coupling and a pair of avoided crossings, which is used to realize an atomic interferometer. The spin polarization and energies of these eigenlevels are characterized by studying the transport of a Bose-Einstein condensate in this system, including observing a Stueckelberg interference.

  8. Method of grid generation

    DOE Patents [OSTI]

    Barnette, Daniel W. (Veguita, NM)

    2002-01-01T23:59:59.000Z

    The present invention provides a method of grid generation that uses the geometry of the problem space and the governing relations to generate a grid. The method can generate a grid with minimized discretization errors, and with minimal user interaction. The method of the present invention comprises assigning grid cell locations so that, when the governing relations are discretized using the grid, at least some of the discretization errors are substantially zero. Conventional grid generation is driven by the problem space geometry; grid generation according to the present invention is driven by problem space geometry and by governing relations. The present invention accordingly can provide two significant benefits: more efficient and accurate modeling since discretization errors are minimized, and reduced cost grid generation since less human interaction is required.

  9. Steam generator support system

    DOE Patents [OSTI]

    Moldenhauer, J.E.

    1987-08-25T23:59:59.000Z

    A support system for connection to an outer surface of a J-shaped steam generator for use with a nuclear reactor or other liquid metal cooled power source is disclosed. The J-shaped steam generator is mounted with the bent portion at the bottom. An arrangement of elongated rod members provides both horizontal and vertical support for the steam generator. The rod members are interconnected to the steam generator assembly and a support structure in a manner which provides for thermal distortion of the steam generator without the transfer of bending moments to the support structure and in a like manner substantially minimizes forces being transferred between the support structure and the steam generator as a result of seismic disturbances. 4 figs.

  10. Steam generator support system

    DOE Patents [OSTI]

    Moldenhauer, James E. (Simi Valley, CA)

    1987-01-01T23:59:59.000Z

    A support system for connection to an outer surface of a J-shaped steam generator for use with a nuclear reactor or other liquid metal cooled power source. The J-shaped steam generator is mounted with the bent portion at the bottom. An arrangement of elongated rod members provides both horizontal and vertical support for the steam generator. The rod members are interconnected to the steam generator assembly and a support structure in a manner which provides for thermal distortion of the steam generator without the transfer of bending moments to the support structure and in a like manner substantially minimizes forces being transferred between the support structure and the steam generator as a result of seismic disturbances.

  11. Atomic magnetometer for human magnetoencephalograpy.

    SciTech Connect (OSTI)

    Schwindt, Peter; Johnson, Cort N.

    2010-12-01T23:59:59.000Z

    We have developed a high sensitivity (<5 fTesla/{radical}Hz), fiber-optically coupled magnetometer to detect magnetic fields produced by the human brain. This is the first demonstration of a noncryogenic sensor that could replace cryogenic superconducting quantum interference device (SQUID) magnetometers in magnetoencephalography (MEG) and is an important advance in realizing cost-effective MEG. Within the sensor, a rubidium vapor is optically pumped with 795 laser light while field-induced optical rotations are measured with 780 nm laser light. Both beams share a single optical axis to maximize simplicity and compactness. In collaboration with neuroscientists at The Mind Research Network in Albuquerque, NM, the evoked responses resulting from median nerve and auditory stimulation were recorded with the atomic magnetometer and a commercial SQUID-based MEG system with signals comparing favorably. Multi-sensor operation has been demonstrated with two AMs placed on opposite sides of the head. Straightforward miniaturization would enable high-density sensor arrays for whole-head magnetoencephalography.

  12. Talkin’ Bout Wind Generation

    Broader source: Energy.gov [DOE]

    The amount of electricity generated by the wind industry started to grow back around 1999, and since 2007 has been increasing at a rapid pace.

  13. SNE TRAFIC GENERATOR

    Energy Science and Technology Software Center (OSTI)

    003027MLTPL00 Network Traffic Generator for Low-rate Small Network Equipment Software  http://eln.lbl.gov/sne_traffic_gen.html 

  14. Hydrogen Generation for Refineries

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

    Single Cycle Shown for ATB SteamCarbon 3 * ATB reforming * Steamcarbon 3 * Syngas generated during reforming * 70% H 2 * 20% CO * Syngas composition agrees with...

  15. Next-generation transcriptome assembly

    E-Print Network [OSTI]

    Martin, Jeffrey A.

    2012-01-01T23:59:59.000Z

    technologies - the next generation. Nat Rev Genet 11, 31-algorithms for next-generation sequencing data. Genomicsassembly from next- generation sequencing data. Genome Res

  16. Scattering properties of dark atoms and molecules

    E-Print Network [OSTI]

    James M. Cline; Zuowei Liu; Guy D. Moore; Wei Xue

    2014-01-15T23:59:59.000Z

    There has been renewed interest in the possibility that dark matter exists in the form of atoms, analogous to those of the visible world. An important input for understanding the cosmological consequences of dark atoms is their self-scattering. Making use of results from atomic physics for the potentials between hydrogen atoms, we compute the low-energy elastic scattering cross sections for dark atoms. We find an intricate dependence upon the ratio of the dark proton to electron mass, allowing for the possibility to "design" low-energy features in the cross section. Dependences upon other parameters, namely the gauge coupling and reduced mass, scale out of the problem by using atomic units. We derive constraints on the parameter space of dark atoms by demanding that their scattering cross section does not exceed bounds from dark matter halo shapes. We discuss the formation of molecular dark hydrogen in the universe, and determine the analogous constraints on the model when the dark matter is predominantly in molecular form.

  17. Scattering properties of dark atoms and molecules

    E-Print Network [OSTI]

    Cline, James M; Moore, Guy; Xue, Wei

    2013-01-01T23:59:59.000Z

    There has been renewed interest in the possibility that dark matter exists in the form of atoms, analogous to those of the visible world. An important input for understanding the cosmological consequences of dark atoms is their self-scattering. Making use of results from atomic physics for the potentials between hydrogen atoms, we compute the low-energy elastic scattering cross sections for dark atoms. We find an intricate dependence upon the ratio of the dark proton to electron mass, allowing for the possibility to "design" low-energy features in the cross section. Dependences upon other parameters, namely the gauge coupling and reduced mass, scale out of the problem by using atomic units. We derive constraints on the parameter space of dark atoms by demanding that their scattering cross section does not exceed bounds from dark matter halo shapes. We discuss the formation of molecular dark hydrogen in the universe, and determine the analogous constraints on the model when the dark matter is predominantly in ...

  18. Ps-atom scattering at low energies

    E-Print Network [OSTI]

    Fabrikant, I I

    2015-01-01T23:59:59.000Z

    A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at $v<1$ a.u. Our results show that the effect of the Ps-atom van der Waals interaction is weak compared to the polarization interaction in electron-atom and positron-atom scattering. As a result, the Ps scattering length for both Ar and Kr is positive, and the Ramsauer-Townsend minimum is not observed for Ps scattering from these targets. This makes Ps scattering quite different from electron scattering in the low-energy region, in contrast to the inter...

  19. Studying coherence in ultra-cold atomic gases

    E-Print Network [OSTI]

    Miller, Daniel E. (Daniel Edward)

    2007-01-01T23:59:59.000Z

    This thesis will discuss the study of coherence properties of ultra-cold atomic gases. The atomic systems investigated include a thermal cloud of atoms, a Bose-Einstein condensate and a fermion pair condensate. In each ...

  20. 1984 Bibliography of atomic and molecular processes

    SciTech Connect (OSTI)

    Barnett, C.F.; Gilbody, H.B.; Gregory, D.C.; Griffin, P.M.; Havener, C.C.; Howard, A.M.; Kirkpatrick, M.I.; McDaniel, E.W.; Meyer, F.W.; Morgan, T.J. (comps.)

    1985-04-01T23:59:59.000Z

    This annotated bibliography includes papers on atomic and molecular processes published during 1984. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.

  1. 1985 bibliography of atomic and molecular processes

    SciTech Connect (OSTI)

    Barnett, C.F.; Gilbody, H.B.; Gregory, D.C.; Griffin, P.M.; Havener, C.C.; Howald, A.M.; Kirkpatrick, M.I.; McDaniel, E.W.; Meyer, F.W.; Morgan, T.J. (comps.)

    1986-06-01T23:59:59.000Z

    This annotated bibliography includes papers on atomic and molecular processes published during 1985. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.

  2. Gain narrowing in few-atom systems

    E-Print Network [OSTI]

    Tom Savels; Allard P. Mosk; Ad Lagendijk

    2006-05-31T23:59:59.000Z

    Using a density matrix approach, we study the simplest systems that display both gain and feedback: clusters of 2 to 5 atoms, one of which is pumped. The other atoms supply feedback through multiple scattering of light. We show that, if the atoms are in each other's near-field, the system exhibits large gain narrowing and spectral mode redistribution. The observed phenomena are more pronounced if the feedback is enhanced. Our system is to our knowledge the simplest exactly solvable microscopic system which shows the approach to laser oscillation.

  3. Cold Light from Hot Atoms and Molecules

    SciTech Connect (OSTI)

    Lister, Graeme [OSRAM SYLVANIA, CRSL, 71 Cherry Hill Drive, Beverly, MA (United States); Curry, John J. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    2011-05-11T23:59:59.000Z

    The introduction of rare earth atoms and molecules into lighting discharges led to great advances in efficacy of these lamps. Atoms such as Dy, Ho and Ce provide excellent radiation sources for lighting applications, with rich visible spectra, such that a suitable combination of these elements can provide high quality white light. Rare earth molecules have also proved important in enhancing the radiation spectrum from phosphors in fluorescent lamps. This paper reviews some of the current aspects of lighting research, particularly rare earth chemistry and radiation, and the associated fundamental atomic and molecular data.

  4. An Atom Trap Relying on Optical Pumping

    E-Print Network [OSTI]

    P. Bouyer; P. Lemonde; M. Ben Dahan; A. Michaud; C. Salomon; J. Dalibard

    2005-09-21T23:59:59.000Z

    We have investigated a new radiation pressure trap which relies on optical pumping and does not require any magnetic field. It employs six circularly polarized divergent beams and works on the red of a $J_{g} \\longrightarrow J_{e} = J_{g} + 1$ atomic transition with $J_{g} \\geq 1/2$. We have demonstrated this trap with cesium atoms from a vapour cell using the 852 nm $J_{g} = 4 \\longrightarrow J_{e} = 5$ resonance transition. The trap contained up to $3 \\cdot 10^{7}$ atoms in a cloud of $1/\\sqrt{e}$ radius of 330 $\\mu$m.

  5. The Manhattan Project: Making the atomic bomb

    SciTech Connect (OSTI)

    Gosling, F.G.

    1994-09-01T23:59:59.000Z

    This article is a short history of the origins and development of the American atomic bomb program during World War II. Beginning with the scientific developments of the pre-war years, the monograph details the role of US government in conducting a secret, nationwide enterprise that took science from the laboratory and into combat with an entirely new type of weapon. The monograph concludes with a discussion of the immediate postwar period, the debate over the Atomic Energy Act of 1946, and the founding of the Atomic Energy Commission.

  6. 1982 bibliography of atomic and molecular processes

    SciTech Connect (OSTI)

    Barnett, C.F.; Crandall, D.H.; Gilbody, H.B.; Gregory, D.C.; Kirkpatrick, M.I.; McDaniel, E.W.; McKnight, R.H.; Meyer, F.W.; Morgan, T.J.; Phaneuf, R.A. (comps.)

    1984-05-01T23:59:59.000Z

    This annotated bibliography includes papers on atomic and molecular processes published during 1982. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.

  7. Numerical estimation on free electrons generated by shielded radioactive materials under various gaseous environments

    SciTech Connect (OSTI)

    Kim, D. S. [Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); Lee, W. S.; So, J. H. [Agency for Defence Development (ADD), Daejeon 305-152 (Korea, Republic of); Choi, E. M. [Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); School of Electrical and Computer Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of)

    2013-06-15T23:59:59.000Z

    We report simulation results on generation of free electrons due to the presence of radioactive materials under controlled pressure and gases using a general Monte Carlo transport code (MCNPX). A radioactive material decays to lower atomic number, simultaneously producing high energy gamma rays that can generate free electrons via various scattering mechanisms. This paper shows detailed simulation works for answering how many free electrons can be generated under the existence of shielded radioactive materials as a function of pressure and types of gases.

  8. Second generation PFB for advanced power generation

    SciTech Connect (OSTI)

    Robertson, A.; Van Hook, J.

    1995-11-01T23:59:59.000Z

    Research is being conducted under a United States Department of Energy (USDOE) contract to develop a new type of coal-fueled plant for electric power generation. This new type of plant-called an advanced or second-generation pressurized fluidized bed combustion (APFBC) plant-offers the promise of 45-percent efficiency (HHV), with emissions and a cost of electricity that are significantly lower than conventional pulverized-coal-fired plants with scrubbers. This paper summarizes the pilot plant R&D work being conducted to develop this new type of plant. Although pilot plant testing is still underway, preliminary estimates indicate the commercial plant Will perform better than originally envisioned. Efficiencies greater than 46 percent are now being predicted.

  9. Contracting for wind generation

    E-Print Network [OSTI]

    Newbery, David

    The UK Government proposes offering long-term Feed-in-Tariffs (FiTs) to low-carbon generation to reduce risk and encourage new entrants. Their preference is for a Contract-for-Difference (CfD) or a premium FiT (pFiT) for all generation regardless...

  10. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, B.E.; Duncan, D.B.

    1994-02-15T23:59:59.000Z

    Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus is described. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 7 figures.

  11. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, B.E.; Duncan, D.B.

    1993-12-28T23:59:59.000Z

    Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 11 figures.

  12. The fifth generation computer

    SciTech Connect (OSTI)

    Moto-Oka, T.; Kitsuregawa, M.

    1985-01-01T23:59:59.000Z

    The leader of Japan's Fifth Generation computer project, known as the 'Apollo' project, and a young computer scientist elucidate in this book the process of how the idea came about, international reactions, the basic technology, prospects for realization, and the abilities of the Fifth Generation computer. Topics considered included forecasting, research programs, planning, and technology impacts.

  13. Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of AlZn

    E-Print Network [OSTI]

    Morse, Michael D.

    Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of Al-block main group element, aluminum, and the 3d series of transi- tion metal atoms. Although the bonding in Al

  14. acoustic wave atomization: Topics by E-print Network

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

    of fluid and acoustic computations, hybrid methodologies still Kohlenbach, Ulrich 12 Propagation of atomic matter waves inside an atom wave guide Quantum Physics (arXiv)...

  15. atomic emission spectrometry: Topics by E-print Network

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

    not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a...

  16. atomic photoabsorption process: Topics by E-print Network

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

    individual sites within atom-trap arrays. Cecilia Muldoon; Lukas Brandt; Jian Dong; Dustin Stuart; Edouard Brainis; Matthew Himsworth; Axel Kuhn 2012-03-21 306 Atomic...

  17. Structure of ?-Alumina: Toward The Atomic Level Understanding...

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

    -Alumina: Toward The Atomic Level Understanding Of Transition Alumina Phases. Structure of -Alumina: Toward The Atomic Level Understanding Of Transition Alumina Phases....

  18. Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions...

    National Nuclear Security Administration (NNSA)

    Our Jobs Working at NNSA Blog Home About Us Our History NNSA Timeline Atomic Energy Commission Explores Peaceful Uses of ... Atomic Energy Commission Explores Peaceful...

  19. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium...

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

    Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys....

  20. atomic carbon nanowires: Topics by E-print Network

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

    Page Topic Index 1 Electron Transport Properties of Atomic Carbon Nanowires between Graphene Electrodes CERN Preprints Summary: Long, stable and free-standing linear atomic...

  1. Isolation, Characterization of an Intermediate in an Oxygen Atom...

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

    Characterization of an Intermediate in an Oxygen Atom-Transfer Reaction, and the Determination of the Bond Isolation, Characterization of an Intermediate in an Oxygen Atom-Transfer...

  2. atom trap trace: Topics by E-print Network

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

    1 An atom trap trace analysis system for measuring krypton contamination in xenon dark matter detectors Physics Websites Summary: An atom trap trace analysis system for measuring...

  3. Materials, Modules, and Systems: An Atoms to Autos Approach to...

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

    Materials, Modules, and Systems: An Atoms to Autos Approach to Automotive Thermoelectric Systems Development Materials, Modules, and Systems: An Atoms to Autos Approach to...

  4. atomic number: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  5. atomic number density: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Quantum Physics (arXiv) Summary: We study atom-atom correlations and relative...

  6. atomic mass number: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  7. atomic number electron: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  8. atom interferometry measurement: Topics by E-print Network

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

    Bose-condensed atoms . Open Access Theses and Dissertations Summary: ??Bose-Einstein condensates are coherent matter waves, produced by cooling gaseous atomic clouds to ultra-low...

  9. atomic wave packets: Topics by E-print Network

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

    Statistics of atomic populations in output coupled wave packets from Bose-Einstein condensates: Four-wave mixing Physics Websites Summary: Statistics of atomic populations in...

  10. atomic number range: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  11. atom interferometry progress: Topics by E-print Network

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

    Bose-condensed atoms . Open Access Theses and Dissertations Summary: ??Bose-Einstein condensates are coherent matter waves, produced by cooling gaseous atomic clouds to ultra-low...

  12. Adsorption of Atoms and Molecules Physisorption

    E-Print Network [OSTI]

    Glashausser, Charles

    Adsorption of Atoms and Molecules Physisorption Chemisorption Surface Bonding Kinetics of Adsorption/Diffusion/Desorption (Scattering Dynamics) #12;Outcomes of Collision Process Rebound (elastically or inelastically) Elastic Scattering Inelastic Scattering Accomodation (thermalizing) Adsorption E V(r) r

  13. FREQUENCY DEPENDENT MULTIPOLE POLARIZABILITIES OF ATOMIC SYSTEMS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1259 FREQUENCY DEPENDENT MULTIPOLE POLARIZABILITIES OF ATOMIC SYSTEMS S. I. EASA and G. C. SHUKLA et d'helium. Abstract. 2014 A variational calculation for frequency dependent multipole 1978, Classification Physics Abstracts 31.10 The calculation of multipole polarizabilities

  14. Electronic transport in atomically thin layered materials

    E-Print Network [OSTI]

    Baugher, Britton William Herbert

    2014-01-01T23:59:59.000Z

    Electronic transport in atomically thin layered materials has been a burgeoning field of study since the discovery of isolated single layer graphene in 2004. Graphene, a semi-metal, has a unique gapless Dirac-like band ...

  15. Accurate capacitive metrology for atomic force microscopy

    E-Print Network [OSTI]

    Mazzeo, Aaron D. (Aaron David), 1979-

    2005-01-01T23:59:59.000Z

    This thesis presents accurate capacitive sensing metrology designed for a prototype atomic force microscope (AFM) originally developed in the MIT Precision Motion Control Lab. The capacitive measurements use a set of ...

  16. Quantum Structures of the Hydrogen Atom

    E-Print Network [OSTI]

    J. Jeknic-Dugic; M. Dugic; A. Francom; M. Arsenijevic

    2014-05-28T23:59:59.000Z

    Modern quantum theory introduces quantum structures (decompositions into subsystems) as a new discourse that is not fully comparable with the classical-physics counterpart. To this end, so-called Entanglement Relativity appears as a corollary of the universally valid quantum mechanics that can provide for a deeper and more elaborate description of the composite quantum systems. In this paper we employ this new concept to describe the hydrogen atom. We offer a consistent picture of the hydrogen atom as an open quantum system that naturally answers the following important questions: (a) how do the so called "quantum jumps" in atomic excitation and de-excitation occur? and (b) why does the classically and seemingly artificial "center-of-mass + relative degrees of freedom" structure appear as the primarily operable form in most of the experimental reality of atoms?

  17. United Nations Atomic Energy Commission stalls out

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

    commission would be short-lived and would not result in the desired control of atomic energy. In the wake of the disappointing results of the Moscow meeting, the United States...

  18. Moving closer to the Atomic Energy Commission

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

    in some way. On October 3, 1945 the president addressed Congress on the subject of atomic energy. Here he first mentioned the need for international agreements. Attempts were made...

  19. Quantum micro-mechanics with ultracold atoms

    E-Print Network [OSTI]

    Thierry Botter; Daniel Brooks; Subhadeep Gupta; Zhao-Yuan Ma; Kevin L. Moore; Kater W. Murch; Tom P. Purdy; Dan M. Stamper-Kurn

    2008-10-21T23:59:59.000Z

    In many experiments isolated atoms and ions have been inserted into high-finesse optical resonators for the study of fundamental quantum optics and quantum information. Here, we introduce another application of such a system, as the realization of cavity optomechanics where the collective motion of an atomic ensemble serves the role of a moveable optical element in an optical resonator. Compared with other optomechanical systems, such as those incorporating nanofabricated cantilevers or the large cavity mirrors of gravitational observatories, our cold-atom realization offers direct access to the quantum regime. We describe experimental investigations of optomechanical effects, such as the bistability of collective atomic motion and the first quantification of measurement backaction for a macroscopic object, and discuss future directions for this nascent field.

  20. Remote-State Prparation eines einzelnen Atoms

    E-Print Network [OSTI]

    Weinfurter, Harald

    Remote-State Präparation eines einzelnen Atoms Diplomarbeit am Department für Physik der Ludwig . . . . . . . . . . . . . . . . . . . . . 8 1.3.3 Remote-State-Präparation . . . . . . . . . . . . . . . . . . . . . 11 1.3.4 Zusammenfassung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 3 Remote-State-Präparation 31 3.1 Einleitung

  1. Electrical Analogs of Atomic Radiative Decay Processes

    E-Print Network [OSTI]

    Fontana, Peter R.; Srivastava, Rajendra P.

    1977-03-01T23:59:59.000Z

    Simple electrical circuits are analyzed, and the results show that for high frequencies they have frequency and time responses identical to the spontaneous radiative decays of atoms. As an illustration of the analogy a two-circuit electrical system...

  2. Atomic vapor spectroscopy in integrated photonic structures

    E-Print Network [OSTI]

    Ritter, Ralf; Pernice, Wolfram; Kübler, Harald; Pfau, Tilman; Löw, Robert

    2015-01-01T23:59:59.000Z

    We investigate an integrated optical chip immersed in atomic vapor providing several waveguide geometries for spectroscopy applications. The narrow-band transmission through a silicon nitride waveguide and interferometer is altered when the guided light is coupled to a vapor of rubidium atoms via the evanescent tail of the waveguide mode. We use grating couplers to couple between the waveguide mode and the radiating wave, which allow for addressing arbitrary coupling positions on the chip surface. The evanescent atom-light interaction can be numerically simulated and shows excellent agreement with our experimental data. This work demonstrates a next step towards miniaturization and integration of alkali atom spectroscopy and provides a platform for further fundamental studies of complex waveguide structures.

  3. An alternative power spectrum of the resonance fluorescence of atomic systems

    E-Print Network [OSTI]

    Adam Stokes; Almut Beige

    2014-08-31T23:59:59.000Z

    We adopt an open quantum systems perspective to calculate the power spectrum associated with the electric field generated by an atomic dipole moment undergoing resonant laser-driving. This spectrum has a similar shape to the usual Mollow spectrum, but also has some distinct features. For sufficiently strong laser driving, both spectra have a symmetric triplet structure with a large central peak and two sidebands. However, the relative height of the sidebands to the central peak differs in each case. The two spectra also behave quite differently when the laser Rabi frequency is varied. Both spectra may be of interest in high-precision experiments into the quantum physics of atomic systems, especially artificial atoms.

  4. Backaction-Driven Transport of Bloch Oscillating Atoms in Ring Cavities

    E-Print Network [OSTI]

    J. Goldwin; B. Prasanna Venkatesh; D. H. J. O'Dell

    2014-08-19T23:59:59.000Z

    We predict that an atomic Bose-Einstein condensate strongly coupled to an intracavity optical lattice can undergo resonant tunneling and directed transport when a constant and uniform bias force is applied. The bias force induces Bloch oscillations, causing amplitude and phase modulation of the lattice which resonantly modifies the site-to-site tunneling. For the right choice of parameters a net atomic current is generated. The transport velocity can be oriented oppositely to the bias force, with its amplitude and direction controlled by the detuning between the pump laser and the cavity. The transport can also be enhanced through imbalanced pumping of the two counter-propagating running wave cavity modes. Our results add to the cold atoms quantum simulation toolbox, with implications for quantum sensing and metrology.

  5. Hydrogen atom in rotationally invariant noncommutative space

    E-Print Network [OSTI]

    Kh. P. Gnatenko; V. M. Tkachuk

    2014-11-03T23:59:59.000Z

    We consider the noncommutative algebra which is rotationally invariant. The hydrogen atom is studied in a rotationally invariant noncommutative space. We find the corrections to the energy levels of the hydrogen atom up to the second order in the parameter of noncommutativity. The upper bound of the parameter of noncommutativity is estimated on the basis of the experimental results for 1s-2s transition frequency.

  6. Atomic resolution images of graphite in air

    SciTech Connect (OSTI)

    Grigg, D.A.; Shedd, G.M.; Griffis, D.; Russell, P.E.

    1988-12-01T23:59:59.000Z

    One sample used for proof of operation for atomic resolution in STM is highly oriented pyrolytic graphite (HOPG). This sample has been imaged with many different STM`s obtaining similar results. Atomic resolution images of HOPG have now been obtained using an STM designed and built at the Precision Engineering Center. This paper discusses the theoretical predictions and experimental results obtained in imaging of HOPG.

  7. Controlling the Ratchet Effect for Cold Atoms

    E-Print Network [OSTI]

    Anatole Kenfack; Jiangbin Gong; Arjendu K. Pattanayak

    2007-11-27T23:59:59.000Z

    Low-order quantum resonances manifested by directed currents have been realized with cold atoms. Here we show that by increasing the strength of an experimentally achievable delta-kicking ratchet potential, quantum resonances of a very high order may naturally emerge and can induce larger ratchet currents than low-order resonances, with the underlying classical limit being fully chaotic. The results offer a means of controlling quantum transport of cold atoms.

  8. ac-driven atomic quantum motor

    E-Print Network [OSTI]

    A. V. Ponomarev; S. Denisov; P. Hanggi

    2009-06-09T23:59:59.000Z

    We invent an ac-driven quantum motor consisting of two different, interacting ultracold atoms placed into a ring-shaped optical lattice and submerged in a pulsating magnetic field. While the first atom carries a current, the second one serves as a quantum starter. For fixed zero-momentum initial conditions the asymptotic carrier velocity converges to a unique non-zero value. We also demonstrate that this quantum motor performs work against a constant load.

  9. Use of Slip Ring Induction Generator for Wind Power Generation

    E-Print Network [OSTI]

    K Y Patil; D S Chavan

    Wind energy is now firmly established as a mature technology for electricity generation. There are different types of generators that can be used for wind energy generation, among which Slip ring Induction generator proves to be more advantageous. To analyse application of Slip ring Induction generator for wind power generation, an experimental model is developed and results are studied. As power generation from natural sources is the need today and variable speed wind energy is ample in amount in India, it is necessary to study more beneficial options for wind energy generating techniques. From this need a model is developed by using Slip ring Induction generator which is a type of Asynchronous generator.

  10. From Lattice Gauge Theories to Hydrogen Atoms

    E-Print Network [OSTI]

    Manu Mathur; T. P. Sreeraj

    2014-10-13T23:59:59.000Z

    Using canonical transformations we obtain a complete and most economical realization of the loop or physical Hilbert space of pure $SU(2)_{2+1}$ lattice gauge theory in terms of Wigner coupled Hilbert spaces of hydrogen atoms. One hydrogen atom is assigned to every plaquette of the lattice. The SU(2) gauge theory loop basis states over a plaquette are the bound energy eigenstates $|n l m>$ of the corresponding hydrogen atom. The Wigner couplings of these hydrogen atom energy eigenstates on different plaquettes provide a complete SU(2) gauge theory loop basis on the entire lattice. The loop basis is invariant under simultaneous rotations of all hydrogen atoms. The dual description of this basis diagonalizes all Wilson loop operators and is given in terms of hyperspherical harmonics on the SU(2) group manifold $S^3$. The SU(2) loop dynamics is governed by a "SU(2) spin Hamiltonian" without any gauge fields. The relevance of the hydrogen atom basis and its dynamical symmetry group SO(4,2) in SU(2) loop dynamics in weak coupling continuum limit ($g^2\\rightarrow 0$) is emphasized.

  11. Excess optical quantum noise in atomic sensors

    E-Print Network [OSTI]

    Irina Novikova; Eugeniy E. Mikhailov; Yanhong Xiao

    2014-10-14T23:59:59.000Z

    Enhanced nonlinear optical response of a coherent atomic medium is the basis for many atomic sensors, and their performance is ultimately limited by the quantum fluctuations of the optical read-out. Here we demonstrate that off-resonant interactions can significantly modify the quantum noise of the optical field, even when their effect on the mean signal is negligible. We illustrate this concept by using an atomic magnetometer based on the nonlinear Faraday effect: the rotation of the light polarization is mainly determined by the resonant light-induced spin alignment, which alone does not change the photon statistics of the optical probe. Yet, we found that the minimum noise of output polarization rotation measurements is above the expected shot noise limit. This excess quantum noise is due to off-resonant coupling and grows with atomic density. We also show that the detection scheme can be modified to reduce the measured quantum noise (even below the shot-noise limit) but only at the expense of the reduced rotational sensitivity. These results show the existence of previously unnoticed factors in fundamental limitations in atomic magnetometry and could have impacts in many other atom-light based precision measurements.

  12. Atoms 2014, 2, 157-177; doi:10.3390/atoms2020157 OPEN ACCESS

    E-Print Network [OSTI]

    Atoms 2014, 2, 157-177; doi:10.3390/atoms2020157 OPEN ACCESS atomsISSN 2218-2004 www]: = ne2 ¯h2 - dt1 t1 - dt2E(t1)·E(t2)ei (t1-t2) (3) where E(t1)·E(t2) = 2 3 0 vf(v)dv max 0 dE(t1

  13. Compact neutron generator

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Lou, Tak Pui

    2005-03-22T23:59:59.000Z

    A compact neutron generator has at its outer circumference a toroidal shaped plasma chamber in which a tritium (or other) plasma is generated. A RF antenna is wrapped around the plasma chamber. A plurality of tritium ion beamlets are extracted through spaced extraction apertures of a plasma electrode on the inner surface of the toroidal plasma chamber and directed inwardly toward the center of neutron generator. The beamlets pass through spaced acceleration and focusing electrodes to a neutron generating target at the center of neutron generator. The target is typically made of titanium tubing. Water is flowed through the tubing for cooling. The beam can be pulsed rapidly to achieve ultrashort neutron bursts. The target may be moved rapidly up and down so that the average power deposited on the surface of the target may be kept at a reasonable level. The neutron generator can produce fast neutrons from a T-T reaction which can be used for luggage and cargo interrogation applications. A luggage or cargo inspection system has a pulsed T-T neutron generator or source at the center, surrounded by associated gamma detectors and other components for identifying explosives or other contraband.

  14. Electrochemical Oxidation of H2 Catalyzed by Ruthenium Hydride Complexes Bearing P2N2 Ligands With Pendant Amines as Proton Relays

    SciTech Connect (OSTI)

    Liu, Tianbiao L.; Rakowski DuBois, Mary; DuBois, Daniel L.; Bullock, R. Morris

    2014-11-03T23:59:59.000Z

    Two Ru hydride complexes (Cp*Ru(PPh2NBn2)H, 1-H and (Cp*Ru(PtBu2NBn2)H, 2-H) supported by cyclic PR2NR'2 ligands (Cp* = ?5-C5Me5; 1,5-diaza-3,7-diphosphacyclooctane, where R = Ph or tBu and R' = Bn) have been synthesized and fully characterized. Both complexes are demonstrated to be electrocatalysts for oxidation of H2 (1 atm, 22 °C) in the presence of external base, DBU (1,8-diazabicyclo[5.4.0]undec-7-ene). The turnover frequency of 2-H is 1.2 s-1, with an overpotential at Ecat/2 of 0.45 V, while catalysis by 1-H has a turnover frequency of 0.6 s-1 and an overpotential of 0.6 V at Ecat/2. Addition of H2O facilitates oxidation of H2 by 2-H and increases its turnover frequency to 1.9 s-1 while , H2O slows down the catalysis by 1-H. The different effects of H2O for 1-H and 2-H are ascribed to different binding affinities of H2O to the Ru center of the corresponding unsaturated species, [Cp*Ru(PPh2NBn2)]+ and [Cp*Ru(PPh2NBn2)]+. In addition, studies of Cp*Ru(dmpm)H (where dmpm = bis(dimethylphosphino)methane), a control complex lacking pendent amines in its diphosphine ligand, confirms the critical roles of the pendent amines of P2N2 ligands for oxidation of H2. We thank the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences, for supporting initial parts of the work. Current work is supported by the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

  15. Single photon absorption by a single atom: from heralded absorption to polarization state mapping

    E-Print Network [OSTI]

    Nicolas Piro; Jürgen Eschner

    2015-02-19T23:59:59.000Z

    Together with photon emission, the absorption of a single photon by a single atom is a fundamental process in matter-light interaction that manifests its quantum mechanical nature. As an experimentally controlled process, it is a key tool for the realization of quantum technologies. In particular, in an atom/photon based quantum network scenario, in which localized atomic particles are used as quantum information processing nodes while photons are used as carriers of quantum information between distant nodes, controlling both emission and absorption of single photons by single atoms is required for quantum coherent state mapping between the two entities. Most experimental efforts to date have focused on establishing the control of single photon emission by single trapped atoms, and the implementation of quantum networking protocols using this interaction. In this chapter, we describe experimental efforts to control the process of single photon absorption by single trapped ions. We describe a series of experiments in which polarization entangled photon pairs, generated by a spontaneous parametric down-conversion source, are coupled to a single ion. First the source is operated to generate heralded single photons, and coincidences between the absorption event of one photon of the pair and the detection of the heralding partner photon are observed. We then show how polarization control in the process is established, leading to the manifestation of the photonic polarization entanglement in the absorption process. Finally, we introduce protocols in which this interaction scheme is harnessed to perform tasks in a quantum network, such as entanglement distribution among distant nodes of the network, and we demonstrate a specific protocol for heralded, high-fidelity photon-to-atom quantum state transfer.

  16. Atoms for peace and war, 1953-1961: Eisenhower and the Atomic Energy Commission

    SciTech Connect (OSTI)

    Hewlett, Richard G.; Holl, Jack M.

    1989-12-01T23:59:59.000Z

    This third volume in the official history of the U.S. Atomic Energy Commission covers the years of the Eisenhower Administration.

  17. Synthetic guide star generation

    DOE Patents [OSTI]

    Payne, Stephen A.; Page, Ralph H.; Ebbers, Christopher A.; Beach, Raymond J.

    2004-03-09T23:59:59.000Z

    A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

  18. Synthetic guide star generation

    DOE Patents [OSTI]

    Payne, Stephen A. (Castro Valley, CA) [Castro Valley, CA; Page, Ralph H. (Castro Valley, CA) [Castro Valley, CA; Ebbers, Christopher A. (Livermore, CA) [Livermore, CA; Beach, Raymond J. (Livermore, CA) [Livermore, CA

    2008-06-10T23:59:59.000Z

    A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

  19. Graph Generator Survey

    SciTech Connect (OSTI)

    Lothian, Josh [ORNL; Powers, Sarah S [ORNL; Sullivan, Blair D [ORNL; Baker, Matthew B [ORNL; Schrock, Jonathan [ORNL; Poole, Stephen W [ORNL

    2013-12-01T23:59:59.000Z

    The benchmarking effort within the Extreme Scale Systems Center at Oak Ridge National Laboratory seeks to provide High Performance Computing benchmarks and test suites of interest to the DoD sponsor. The work described in this report is a part of the effort focusing on graph generation. A previously developed benchmark, SystemBurn, allowed the emulation of dierent application behavior profiles within a single framework. To complement this effort, similar capabilities are desired for graph-centric problems. This report examines existing synthetic graph generator implementations in preparation for further study on the properties of their generated synthetic graphs.

  20. Generating electricity from viruses

    ScienceCinema (OSTI)

    Lee, Seung-Wuk

    2014-06-23T23:59:59.000Z

    Berkeley Lab's Seung-Wuk Lee discusses "Generating electricity from viruses" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas.

  1. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, James M. (Livermore, CA); Leighton, James F. (Livermore, CA)

    1990-01-01T23:59:59.000Z

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  2. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, J.M.; Leighton, J.F.

    1988-02-05T23:59:59.000Z

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  3. Energy and Mass Generation

    E-Print Network [OSTI]

    Burra G. Sidharth

    2010-03-11T23:59:59.000Z

    Modifications in the energy momentum dispersion laws due to a noncommutative geometry, have been considered in recent years. We examine the oscillations of extended objects in this perspective and find that there is now a "generation" of energy.

  4. Local entropy generation analysis

    SciTech Connect (OSTI)

    Drost, M.K.; White, M.D.

    1991-02-01T23:59:59.000Z

    Second law analysis techniques have been widely used to evaluate the sources of irreversibility in components and systems of components but the evaluation of local sources of irreversibility in thermal processes has received little attention. While analytical procedures for evaluating local entropy generation have been developed, applications have been limited to fluid flows with analytical solutions for the velocity and temperature fields. The analysis of local entropy generation can be used to evaluate more complicated flows by including entropy generation calculations in a computational fluid dynamics (CFD) code. The research documented in this report consists of incorporating local entropy generation calculations in an existing CFD code and then using the code to evaluate the distribution of thermodynamic losses in two applications: an impinging jet and a magnetic heat pump. 22 refs., 13 figs., 9 tabs.

  5. Generating electricity from viruses

    SciTech Connect (OSTI)

    Lee, Seung-Wuk

    2013-10-31T23:59:59.000Z

    Berkeley Lab's Seung-Wuk Lee discusses "Generating electricity from viruses" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas.

  6. Monte Carlo event generators

    SciTech Connect (OSTI)

    Frixione, Stefano [INFN, Sezione di Genova, Via Dodecaneso 33, 16146 Genova (Italy)

    2005-10-06T23:59:59.000Z

    I review recent progress in the physics of parton shower Monte Carlos, emphasizing the ideas which allow the inclusion of higher-order matrix elements into the framework of event generators.

  7. Oscillating fluid power generator

    DOE Patents [OSTI]

    Morris, David C

    2014-02-25T23:59:59.000Z

    A system and method for harvesting the kinetic energy of a fluid flow for power generation with a vertically oriented, aerodynamic wing structure comprising one or more airfoil elements pivotably attached to a mast. When activated by the moving fluid stream, the wing structure oscillates back and forth, generating lift first in one direction then in the opposite direction. This oscillating movement is converted to unidirectional rotational movement in order to provide motive power to an electricity generator. Unlike other oscillating devices, this device is designed to harvest the maximum aerodynamic lift forces available for a given oscillation cycle. Because the system is not subjected to the same intense forces and stresses as turbine systems, it can be constructed less expensively, reducing the cost of electricity generation. The system can be grouped in more compact clusters, be less evident in the landscape, and present reduced risk to avian species.

  8. Steam generator tube failures

    SciTech Connect (OSTI)

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01T23:59:59.000Z

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service.

  9. Strong coupling of an optomechanical system to an anomalously dispersive atomic medium

    E-Print Network [OSTI]

    Haibin Wu; Min Xiao

    2014-07-14T23:59:59.000Z

    We investigate a hybrid optomechanical system in which a membrane oscillator is coupled to a collective spin of ground states of an intracavity $\\Lambda$-type three-level atomic medium. The cavity field response is greatly modified by atomic coherence and the anomalous dispersion generated by two Raman pumping beams near two-photon resonance. The optomechanical interaction, therefore radiation pressure force, is substantially enhanced due to superluminal propagation of photons in the cavity. Such improvement facilitates ground-state cooling of the mechanical oscillator with room temperature thermal environment. Moreover, it can greatly improve the sensitivity and bandwidth of displacement measurement. In such system, optically-controlled strong-coupling interaction between the mechanical oscillator and cavity field could be implemented on small intracavity photon number, even at the single quanta level, which is important for weak-light nonlinear photonics and the generation of nonclassical quantum states in the mechanical field.

  10. High order harmonic generation in dual gas multi-jets

    SciTech Connect (OSTI)

    Tosa, Valer, E-mail: valer.tosa@itim-cj.ro, E-mail: calin.hojbota@itim-cj.ro; Hojbota, Calin, E-mail: valer.tosa@itim-cj.ro, E-mail: calin.hojbota@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, Donath 65-103, 400293 Cluj-Napoca (Romania)] [National Institute for Research and Development of Isotopic and Molecular Technologies, Donath 65-103, 400293 Cluj-Napoca (Romania)

    2013-11-13T23:59:59.000Z

    High order harmonic generation (HHG) in gas media suffers from a low conversion efficiency that has its origins in the interaction of the atom/molecule with the laser field. Phase matching is the main way to enhance the harmonic flux and several solutions have been designed to achieve it. Here we present numerical results modeling HHG in a system of multi-jets in which two gases alternate: the first gas jet (for example Ne) generates harmonics and the second one which ionizes easier, recover the phase matching condition. We obtain configurations which are experimentally feasible with respect to pressures and dimensions of the jets.

  11. 29Counting Atoms in a Molecule The complex molecule Propanal

    E-Print Network [OSTI]

    29Counting Atoms in a Molecule The complex molecule Propanal was discovered in a dense interstellar is the ratio of carbon atoms to hydrogen atoms in propanal? Problem 4 - If the mass of a hydrogen atom of a propanal molecule in AMUs? Problem 5 - What is the complete chemical formula for propanal? C3 H __ O

  12. ATOMIC PHYSICS DMITRY BUDKER | DEREK F. KIMBALL | DAVID P. DEMILLE

    E-Print Network [OSTI]

    Pines, Alexander

    symmetries, atomic magnetometers and frequency comb metrology with ultra-short laser pulses. Dmitry Budker

  13. High-Yield D-T Neutron Generator

    SciTech Connect (OSTI)

    Ludewigt, B.A.; Wells, R.P.; Reijonen, J.

    2006-11-15T23:59:59.000Z

    A high-yield D-T neutron generator has been developed for neutron interrogation in homeland security applications such as cargo screening. The generator has been designed as a sealed tube with a performance goal of producing 5 {center_dot} 10{sup 11} n/s over a long lifetime. The key generator components developed are a radio-frequency (RF) driven ion source and a beam-loaded neutron production target that can handle a beam power of 10 kW. The ion source can provide a 100 mA D{sup +}/T{sup +} beam current with a high fraction of atomic species and can be pulsed up to frequencies of several kHz for pulsed neutron generator operation. Testing in D-D operation has been started.

  14. Isolating and moving single atoms using silicon nanocrystals

    DOE Patents [OSTI]

    Carroll, Malcolm S. (Albuquerque, NM)

    2010-09-07T23:59:59.000Z

    A method is disclosed for isolating single atoms of an atomic species of interest by locating the atoms within silicon nanocrystals. This can be done by implanting, on the average, a single atom of the atomic species of interest into each nanocrystal, and then measuring an electrical charge distribution on the nanocrystals with scanning capacitance microscopy (SCM) or electrostatic force microscopy (EFM) to identify and select those nanocrystals having exactly one atom of the atomic species of interest therein. The nanocrystals with the single atom of the atomic species of interest therein can be sorted and moved using an atomic force microscope (AFM) tip. The method is useful for forming nanoscale electronic and optical devices including quantum computers and single-photon light sources.

  15. Atomic-level imaging, processing and characterization of semiconductor surfaces

    DOE Patents [OSTI]

    Kazmerski, L.L.

    1995-08-22T23:59:59.000Z

    A method for selecting and removing single specific atoms from a solid material surface uses photon biasing to break down bonds that hold the selected atom in the lattice and to reduce barrier effects that hold the atom from transferring to a probe. The photon bias is preferably light or other electromagnetic radiation with a wavelength and frequency that approximately matches the wave function of the target atom species to be removed to induce high energy, selective thermionic-like vibration. An electric field potential is then applied between the probe and the surface of the solid material to pull the atom out of the lattice and to transfer the atom to the probe. Different extrinsic atoms can be installed in the lattice sites that are vacated by the removed atoms by using a photon bias that resonates the extrinsic atom species, reversing polarity of the electric field, and blowing gas comprising the extrinsic atoms through a hollow catheter probe. 8 figs.

  16. Atomic-level imaging, processing and characterization of semiconductor surfaces

    DOE Patents [OSTI]

    Kazmerski, Lawrence L. (Lakewood, CO)

    1995-01-01T23:59:59.000Z

    A method for selecting and removing single specific atoms from a solid material surface uses photon biasing to break down bonds that hold the selected atom in the lattice and to reduce barrier effects that hold the atom from transferring to a probe. The photon bias is preferably light or other electromagnetic radiation with a wavelength and frequency that approximately matches the wave function of the target atom species to be removed to induce high energy, selective thermionic-like vibration. An electric field potential is then applied between the probe and the surface of the solid material to pull the atom out of the lattice and to transfer the atom to the probe. Different extrinsic atoms can be installed in the lattice sites that are vacated by the removed atoms by using a photon bias that resonates the extrinsic atom species, reversing polarity of the electric field, and blowing gas comprising the extrinsic atoms through a hollow catheter probe.

  17. Chapter 44. Cooling and Trapping Neutral Atoms Cooling and Trapping Neutral Atoms

    E-Print Network [OSTI]

    transition. This year, we made progress in developing novel detection and cooling techniques. 1. SpinChapter 44. Cooling and Trapping Neutral Atoms 44-1 Cooling and Trapping Neutral Atoms RLE Groups in optical lattices. Additional cooling methods will be needed to reach this very interesting temperature

  18. High-Resolved X-ray Spectra of Hollow Atoms in a Femtosecond Laser-Produced Solid Plasma

    E-Print Network [OSTI]

    Umstadter, Donald

    High-Resolved X-ray Spectra of Hollow Atoms in a Femtosecond Laser-Produced Solid Plasma A. Ya and interpreted for the ¢rst time. It is shown that such spectra were generated by multicharged hollow ions-ray spectra of nano- and subnanosecond laser produced plasmas were intensively investigated during the last 20

  19. Measurement of positive gain on the 1315 nm transition of atomic iodine pumped by O2,,a1

    E-Print Network [OSTI]

    Carroll, David L.

    state I 2 P3/2 . Conventionally, the O2 1 is produced by a liquid chemistry singlet oxygen generator of gain. © 2004 American Institute of Physics. [DOI: 10.1063/1.1784519] The classic chemical oxygen the metastable excited singlet oxygen molecule, O2 a1 [de- noted O2 1 hereafter], and the iodine atom ground

  20. Hydrogen atom in de Sitter spaces

    E-Print Network [OSTI]

    O. V. Veko; K. V. Kazmerchuk; E. M. Ovsiyuk; V. M. Red'kov; A. M. Ishkhanyan

    2014-12-28T23:59:59.000Z

    The hydrogen atom theory is developed for the de Sitter and anti de Sitter spaces on the basis of the Klein-Gordon-Fock wave equation in static coordinates. In both models, after separation of the variables, the problem is reduced to the general Heun equation, a second order linear differential equation having four regular singular points. A qualitative examination shows that the energy spectrum for the hydrogen atom in the de Sitter space should be quasi-stationary, and the atom should be unstable. We derive an approximate expression for energy levels within the quasi-classical approach and estimate the probability of decay of the atom. A similar analysis shows that in the anti de Sitter model the hydrogen atom should be stable in the quantum-mechanical sense. Using the quasi-classical approach, we derive approximate formulas for energy levels for this case as well. Finally, we present the extension to the case of a spin 1/2 particle for both de Sitter models. This extension leads to complicated differential equations with 8 singular points.