National Library of Energy BETA

Sample records for br baghouse reverse

  1. br Owner br Facility br Type br Capacity br MW br Commercial...

    Open Energy Info (EERE)

    Owner br Facility br Type br Capacity br MW br Commercial br Online br Date br Geothermal br Area br Geothermal br Region Coordinates Ahuachapan Geothermal Power Plant LaGeo SA de...

  2. Using high temperature baghouses to enhance desulfurization following economizer sorbent injection

    SciTech Connect (OSTI)

    Li, G.; Keener, T.C.

    1995-12-31

    In order to explore the potential of using high temperature baghouses to enhance SO{sub 2} removal following upstream sorbent injection, an integrated two-stage reactor system has been built. It consists of an injection stage and a filtration stage. Distinct from one-stage fixed-bed reactors, sorbent particles in this system are initially converted under controlled injection conditions before entering the filtration reactor chamber. By the aid of the system, several unique features regarding the gas-solid reactions in the baghouse after economizer zone sorbent injection have been revealed. Results have shown that the appropriate usage of a high temperature baghouse may substantially enhance the performance of the process. The further SO{sub 2} removal in the baghouse is comprehensively affected by both the conditions in the injection zone and those in the baghouse.

  3. Hydrometallurgical process for recovering iron sulfate and zinc sulfate from baghouse dust

    DOE Patents [OSTI]

    Zaromb, Solomon; Lawson, Daniel B.

    1994-01-01

    A process for recovering zinc/rich and iron-rich fractions from the baghouse dust that is generated in various metallurgical operations, especially in steel-making and other iron-making plants, comprises the steps of leaching the dust by hot concentrated sulfuric acid so as to generate dissolved zinc sulfate and a precipitate of iron sulfate, separating the precipitate from the acid by filtration and washing with a volatile liquid, such as methanol or acetone, and collecting the filtered acid and the washings into a filtrate fraction. The volatile liquid may be recovered distillation, and the zinc may be removed from the filtrate by alternative methods, one of which involves addition of a sufficient amount of water to precipitate hydrated zinc sulfate at 10.degree. C., separation of the precipitate from sulfuric acid by filtration, and evaporation of water to regenerate concentrated sulfuric acid. The recovery of iron may also be effected in alternative ways, one of which involves roasting the ferric sulfate to yield ferric oxide and sulfur trioxide, which can be reconverted to concentrated sulfuric acid by hydration. The overall process should not generate any significant waste stream.

  4. Hydrometallurgical process for recovering iron sulfate and zinc sulfate from baghouse dust

    DOE Patents [OSTI]

    Zaromb, S.; Lawson, D.B.

    1994-02-15

    A process for recovering zinc-rich and iron-rich fractions from the baghouse dust that is generated in various metallurgical operations, especially in steel-making and other iron-making plants, comprises the steps of leaching the dust by hot concentrated sulfuric acid so as to generate dissolved zinc sulfate and a precipitate of iron sulfate, separating the precipitate from the acid by filtration and washing with a volatile liquid, such as methanol or acetone, and collecting the filtered acid and the washings into a filtrate fraction. The volatile liquid may be recovered by distillation, and the zinc may be removed from the filtrate by alternative methods, one of which involves addition of a sufficient amount of water to precipitate hydrated zinc sulfate at 10 C, separation of the precipitate from sulfuric acid by filtration, and evaporation of water to regenerate concentrated sulfuric acid. The recovery of iron may also be effected in alternative ways, one of which involves roasting the ferric sulfate to yield ferric oxide and sulfur trioxide, which can be reconverted to concentrated sulfuric acid by hydration. The overall process should not generate any significant waste stream. 1 figure.

  5. Jatropha BR | Open Energy Information

    Open Energy Info (EERE)

    BR Jump to: navigation, search Name: Jatropha BR Place: Brazil Product: Brazilian-based consortium of five leading Brazilian companies engaged in the integrated jatropha curcas...

  6. X-ray absorption studies of mixed salt polymer electrolytes: ZnBr{sub 2}/CaBr{sub 2}-PEO, ZnBr{sub 2}/LiBr-PEO, and ZnBr{sub 2}/RbBr-PEO complexes

    SciTech Connect (OSTI)

    McBreen, J.; Yang, X.Q.; Lee, H.S.; Okamoto, Y.

    1995-02-01

    Polyethylene oxide (PEO)-salt systems are an important new class of electrolytes that are being considered for many uses. X-ray absorption (XAS) studies of ZnBr{sub 2}-PEO complexes, at the Zn K edge, at temperatures between 25 and 120 C, indicate that additions of bromide salts of Li, Rb, or Ca result in the formation of ZnBr{sub 4}{sup {minus} 2} complexes with a Zn-Br bond length of 2.42 {angstrom}. XAS, at the Rb K edge, in mixed RbBr/ZnBr{sub 2}-PEO complexes with an excess of ZnBr{sub 2}, shows that the ZnBr{sub 2} causes the RbBr to dissolve in the polymer. The Rb{sup +} ions are weakly complexed with the PEO with an Rb-O bond distance of 2.93 {angstrom}.

  7. High energy XeBr electric discharge laser

    DOE Patents [OSTI]

    Sze, Robert C. (Santa Fe, NM); Scott, Peter B. (Los Alamos, NM)

    1981-01-01

    A high energy XeBr laser for producing coherent radiation at 282 nm. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr is used as the halogen donor which undergoes harpooning reactions with Xe.sub.M * to form XeBr*.

  8. Optimization of electrode characteristics for the Br?/H? redox flow cell

    SciTech Connect (OSTI)

    Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Van Nguyen, Trung

    2014-10-17

    The Br?/H? redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and () electrode architecture are investigated. Increasing hydrogen pressure and depositing the () catalyst layer on the membrane instead of on the carbon-paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm-2 and a peak power density of 1.4 W cm-2. Maximum energy efficiency of 79% is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br- reversibly adsorbs at the Pt () electrode for potentials exceeding a critical value, and the extent of Br- coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.

  9. Optimization of electrode characteristics for the Br?/H? redox flow cell

    SciTech Connect (OSTI)

    Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Van Nguyen, Trung

    2015-01-01

    The Br?/H? redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and () electrode architecture are investigated. Increasing hydrogen pressure and depositing the () catalyst layer on the membrane instead of on the carbon-paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm-2 and a peak power density of 1.4 W cm-2. Maximum energy efficiency of 79% is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br- reversibly adsorbs at the Pt () electrode for potentials exceeding a critical value, and the extent of Br- coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.

  10. Optimization of electrode characteristics for the Br-2/H-2 redox flow cell

    SciTech Connect (OSTI)

    Tucker, MC; Cho, KT; Weber, AZ; Lin, GY; Nguyen, TV

    2014-10-17

    The Br-2/H-2 redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (-) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (-) catalyst layer on the membrane instead of on the carbon paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm(-2) and a peak power density of 1.4 W cm(-2). Maximum energy efficiency of 79 % is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br- reversibly adsorbs at the Pt (-) electrode for potentials exceeding a critical value, and the extent of Br- coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.

  11. Reversible Acid Gas Capture

    ScienceCinema (OSTI)

    Dave Heldebrant

    2012-12-31

    Pacific Northwest National Laboratory scientist David Heldebrant demonstrates how a new process called reversible acid gas capture works to pull carbon dioxide out of power plant emissions.

  12. Improved production of Br atoms near zero speed by photodissociating laser aligned Br{sub 2} molecules

    SciTech Connect (OSTI)

    Deng, L. Z., E-mail: lzdeng@phy.ecnu.edu.cn; Yin, J. P., E-mail: jpyin@phy.ecnu.edu.cn [State Key Laboratory of Precision Spectroscopy, Department of Physics, East China Normal University, Shanghai 200062 (China)

    2014-10-28

    We theoretically investigated the improvement on the production rate of the decelerated bromine (Br) atoms near zero speed by photodissociating laser aligned Br{sub 2} precursors. Adiabatic alignment of Br{sub 2} precursors exposed to long laser pulses with duration on the order of nanoseconds was investigated by solving the time-dependent Schrdinger equation. The dynamical fragmentation of adiabatically aligned Br{sub 2} precursors was simulated and velocity distribution of the Br atoms produced was analyzed. Our study shows that the larger the degree of the precursor alignment, ?cos{sup 2}???, the higher the production rate of the decelerated Br atoms near zero speed. For Br{sub 2} molecules with an initial rotational temperature of ?1 K, a ?cos{sup 2}??? value of ?0.88 can result in an improvement factor of over ?20 on the production rate of the decelerated Br atoms near zero speed, requiring a laser intensity of only ?1 10{sup 12} W/cm{sup 2} for alignment.

  13. Reversible Fuel Cells Workshop

    Broader source: Energy.gov [DOE]

    The National Renewable Energy Laboratory hosted a workshop addressing the current state-of-the-art of reversible fuel cells that use hydrogen/air or hydrogen/oxygen on April 19, 2011, at the...

  14. Ca2+-Doped CeBr3 Scintillating Materials

    SciTech Connect (OSTI)

    Guss, Paul; Foster, Michael E.; Wong, Bryan M.; Doty, F. Patrick; Shah, Kanai; Squillante, Michael R.; Shirwadkar, Urmila; Hawrami, Rastgo; Tower, Josh; Yuan, Ding

    2014-01-21

    Despite the outstanding scintillation performance characteristics of cerium tribromide (CeBr3) and cerium-activated lanthanum tribromide, their commercial availability and application are limited due to the difficulties of growing large, crack-free single crystals from these fragile materials. This investigation employed aliovalent doping to increase crystal strength while maintaining the optical properties of the crystal. One divalent dopant (Ca2+) was used as a dopant to strengthen CeBr3 without negatively impacting scintillation performance. Ingots containing nominal concentrations of 1.9% of the Ca2+ dopant were grown. Preliminary scintillation measurements are presented for this aliovalently doped scintillator. Ca2+-doped CeBr3 exhibited little or no change in the peak fluorescence emission for 371 nm optical excitation for CeBr3. The structural, electronic, and optical properties of CeBr3 crystals were studied using the density functional theory within the generalized gradient approximation. The calculated lattice parameters are in good agreement with the experimental data. The energy band structures and density of states were obtained. The optical properties of CeBr3, including the dielectric function, were calculated.

  15. Photoelectron Emission Studies in CsBr at 257 nm

    SciTech Connect (OSTI)

    Maldonado, Juan R.; Liu, Zhi; Sun, Yun; Pianetta, Piero A.; Pease, Fabian W.; /Stanford U., Elect. Eng. Dept. /SLAC, SSRL

    2006-09-28

    CsBr/Cr photocathodes were found [1,2] to meet the requirements of a multi-electron beam lithography system operating with a light energy of 4.8 eV (257nm). The fact that photoemission was observed with a light energy below the reported 7.3 eV band gap for CsBr was not understood. This paper presents experimental results on the presence of intra-band gap absorption sites (IBAS) in CsBr thin film photo electron emitters, and presents a model based on IBAS to explain the observed photoelectron emission behavior at energies below band gap. A fluorescence band centered at 330 nm with a FWHM of about 0.34 eV was observed in CsBr/Cr samples under 257 nm laser illumination which can be attributed to IBAS and agrees well with previously obtained synchrotron photoelectron spectra[1] from the valence band of CsBr films.

  16. Time reversal communication system

    DOE Patents [OSTI]

    Candy, James V. (Danville, CA); Meyer, Alan W. (Danville, CA)

    2008-12-02

    A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

  17. Reversible Solid Oxide Electrolysis

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

    Clean, Efficient, Reliable Power Reversible Solid Oxide Electrolysis Randy Petri Director Product Development & Federal Programs Electrolytic Hydrogen Production Workshop DOE Fuel Cell Technologies Office Hosted by: National Renewable Energy Laboratory, Golden, Colorado February 27th and 28th, 2014 FCE Acquires VPS * FuelCell Energy fully acquired the shares of Versa Power Systems on December 20, 2012. Prior to this, FuelCell Energy owned approximately 39% of Versa "We view solid oxide

  18. Decommissioning of the BR3 reactor: status and perspectives

    SciTech Connect (OSTI)

    Noynaert, L.; Verstraeten, I.

    2007-07-01

    The BR3 plant at Mol in Belgium built at the end of the fifties was the first PWR plant built outside the USA. The reactor had a small net power output (10 MWe) but comprised all the loops and features of a commercial PWR plant. The BR3 plant was operated with the main objective of testing advanced PWR fuels under irradiation conditions similar to those encountered in large commercial PWR plants. The reactor was started in 1962 and shut down in 1987 after 25 years of continuous operation. Since 1989, SCK.CEN is decommissioning the BR3 PWR research reactor. The dismantling of the metallic components including reactor pressure vessel and internals is completed and extensively reported in the literature. The dismantling of auxiliary components and the decontamination of parts of the infrastructure are now going on. The decommissioning progress is continuously monitored and costs and strategy are regularly reassessed. The first part of the paper describes the main results and lessons learned from the reassessment exercises performed in 1994, 1999, 2004 and 2007. Impacts of changes in legal framework on the decommissioning costs will be addressed. These changes concern e.g. licensing aspects, clearance levels, waste management... The middle part of the paper discusses the management of activated and/or contaminated concrete. The costing exercise performed in 1995 highlighted that the management of activated and contaminated concrete is the second main cost item after the dismantling of the reactor pressure vessel and internals. Different possible solutions were studied. These are evacuation as radioactive waste with or without supercompaction, recycling this 'radioactive' grout or concrete for conditioning of radioactive waste e.g. conditioning of metallic waste. The paper will give the results of the cost-benefit analysis made to select the solution retained. The last part of the paper will discuss the end goal of the decommissioning of the BR3. In the final decommissioning plan approved by ONDRAF/NIRAS, it was mentioned that the final goal of the BR3 decommissioning will be the 'green field' unless opportunities for reuse of the BR3 site will occur during decommissioning. A strategy of partial reuse of the BR3 facility is proposed and being discussed with the main stakeholders. The paper will give the present state of the discussion. (authors)

  19. Reversible brazing process

    DOE Patents [OSTI]

    Pierce, Jim D. (Albuquerque, NM); Stephens, John J. (Albuquerque, NM); Walker, Charles A. (Albuquerque, NM)

    1999-01-01

    A method of reversibly brazing surfaces together. An interface is affixed to each surface. The interfaces can be affixed by processes such as mechanical joining, welding, or brazing. The two interfaces are then brazed together using a brazing process that does not defeat the surface to interface joint. Interfaces of materials such as Ni-200 can be affixed to metallic surfaces by welding or by brazing with a first braze alloy. The Ni-200 interfaces can then be brazed together using a second braze alloy. The second braze alloy can be chosen so that it minimally alters the properties of the interfaces to allow multiple braze, heat and disassemble, rebraze cycles.

  20. Reversal bending fatigue testing

    DOE Patents [OSTI]

    Wang, Jy-An John; Wang, Hong; Tan, Ting

    2014-10-21

    Embodiments for apparatuses for testing reversal bending fatigue in an elongated beam are disclosed. Embodiments are configured to be coupled to first and second end portions of the beam and to apply a bending moment to the beam and create a pure bending condition in an intermediate portion of the beam. Embodiments are further configured to cyclically alternate the direction of the bending moment applied to the beam such that the intermediate portion of the beam cyclically bends in opposite directions in a pure bending condition.

  1. A preliminary report on the photoionization efficiency spectrum, ionization energy and heat of formation of Br{sub 2}O; and the appearance energy of BrO{sup +} (Br{sub 2}O)

    SciTech Connect (OSTI)

    Thorn, R.P. Jr.; Monks, P.S.; Stief, L.J.; Kuo, S.C.; Zhang, Z.; Klemm, R.B.

    1995-08-01

    We report experimental results for the photoionization efficiency (PIE) spectrum of Br{sub 2}O along with the ionization energy (derived form the ionization threshold) and the appearance energy (AE) of BrO{sup +} (Br{sub 2}O). A value for the heat of formation of Br{sub 2}O is derived form the AE result. Experiments were performed by employing a discharge flow-photoionization mass spectrometer (DF-PIMS) apparatus coupled to beamline U-11 at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory.

  2. High gradient rf gun studies of CsBr photocathodes

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

    Vecchione, Theodore; Maldonado, Juan R.; Gierman, Stephen; Corbett, Jeff; Hartmann, Nick; Pianetta, Piero A.; Hesselink, Lambertus; Schmerge, John F.

    2015-04-03

    CsBr photocathodes have 10 times higher quantum efficiency with only 3 times larger intrinsic transverse emittance than copper. They are robust and can withstand 80 MV/m fields without breaking down or emitting dark current. They can operate in 2×10⁻⁹ torr vacuum and survive exposure to air. They are well suited for generating high pulse charge in rf guns without a photocathode transfer system.

  3. High gradient rf gun studies of CsBr photocathodes

    SciTech Connect (OSTI)

    Vecchione, Theodore; Maldonado, Juan R.; Gierman, Stephen; Corbett, Jeff; Hartmann, Nick; Pianetta, Piero A.; Hesselink, Lambertus; Schmerge, John F.

    2015-04-03

    CsBr photocathodes have 10 times higher quantum efficiency with only 3 times larger intrinsic transverse emittance than copper. They are robust and can withstand 80 MV/m fields without breaking down or emitting dark current. They can operate in 210?? torr vacuum and survive exposure to air. They are well suited for generating high pulse charge in rf guns without a photocathode transfer system.

  4. Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption...

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

    Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, ...

  5. Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption...

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

    Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP...

  6. Multiple stimulus reversible hydrogels

    DOE Patents [OSTI]

    Gutowska, Anna; Krzyminski, Karol J.

    2006-04-25

    A polymeric solution capable of gelling upon exposure to a critical minimum value of a plurality of environmental stimuli is disclosed. The polymeric solution may be an aqueous solution utilized in vivo and capable of having the gelation reversed if at least one of the stimuli fall below, or outside the range of, the critical minimum value. The aqueous polymeric solution can be used either in industrial or pharmaceutical environments. In the medical environment, the aqueous polymeric solution is provided with either a chemical or radioisotopic therapeutic agent for delivery to a specific body part. The primary advantage of the process is that exposure to one environmental stimuli alone will not cause gelation, thereby enabling the therapeutic agent to be conducted through the body for relatively long distances without gelation occurring.

  7. Multiple stimulus reversible hydrogels

    DOE Patents [OSTI]

    Gutowska, Anna; Krzyminski, Karol J.

    2003-12-09

    A polymeric solution capable of gelling upon exposure to a critical minimum value of a plurality of environmental stimuli is disclosed. The polymeric solution may be an aqueous solution utilized in vivo and capable of having the gelation reversed if at least one of the stimuli fall below, or outside the range of, the critical minimum value. The aqueous polymeric solution can be used either in industrial or pharmaceutical environments. In the medical environment, the aqueous polymeric solution is provided with either a chemical or radioisotopic therapeutic agent for delivery to a specific body part. The primary advantage of the process is that exposure to one environmental stimuli alone will not cause gelation, thereby enabling the therapeutic agent to be conducted through the body for relatively long distances without gelation occurring.

  8. Reverse Osmosis Optimization

    SciTech Connect (OSTI)

    McMordie Stoughton, Kate; Duan, Xiaoli; Wendel, Emily M.

    2013-08-26

    This technology evaluation was prepared by Pacific Northwest National Laboratory on behalf of the U.S. Department of Energys Federal Energy Management Program (FEMP). The technology evaluation assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. This evaluation provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. The evaluation is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system optimization options, enabling them to make informed decisions during the system design process for either new projects or recommissioning of existing equipment. This evaluation is focused on commercial-sized RO systems generally treating more than 80 gallons per hour.

  9. Reverse slapper detonator

    DOE Patents [OSTI]

    Weingart, Richard C. (Livermore, CA)

    1990-01-01

    A reverse slapper detonator (70), and methodology related thereto, are provided. The detonator (70) is adapted to be driven by a pulse of electric power from an external source (80). A conductor (20) is disposed along the top (14), side (18), and bottom (16) surfaces of a sheetlike insulator (12). Part of the conductor (20) comprises a bridge (28), and an aperture (30) is positioned within the conductor (20), with the bridge (28) and the aperture (30) located on opposite sides of the insulator (12). A barrel (40) and related explosive charge (50) are positioned adjacent to and in alignment with the aperture (30), and the bridge (28) is buttressed with a backing layer (60). When the electric power pulse vaporizes the bridge (28), a portion of the insulator (12) is propelled through the aperture (30) and barrel (40), and against the explosive charge (50), thereby detonating it.

  10. Reverse photoacoustic standoff spectroscopy

    DOE Patents [OSTI]

    Van Neste, Charles W. (Kingston, TN); Senesac, Lawrence R. (Knoxville, TN); Thundat, Thomas G. (Knoxville, TN)

    2011-04-12

    A system and method are disclosed for generating a reversed photoacoustic spectrum at a greater distance. A source may emit a beam to a target and a detector measures signals generated as a result of the beam being emitted on the target. By emitting a chopped/pulsed light beam to the target, it may be possible to determine the target's optical absorbance by monitoring the intensity of light collected at the detector at different wavelengths. As the wavelength of light is changed, the target may absorb or reject each optical frequency. Rejection may increase the intensity at the sensing element and absorption may decrease the intensity. Accordingly, an identifying spectrum of the target may be made with the intensity variation of the detector as a function of illuminating wavelength.

  11. Reverse Osmosis Optimization

    SciTech Connect (OSTI)

    2013-08-01

    This technology evaluation was prepared by Pacific Northwest National Laboratory on behalf of the U.S. Department of Energys Federal Energy Management Program (FEMP). The technology evaluation assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. This evaluation provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. The evaluation is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system optimization options, enabling them to make informed decisions during the system design process for either new projects or recommissioning of existing equipment. This evaluation is focused on commercial-sized RO systems generally treating more than 80 gallons per hour.

  12. Improved Growth Methods for LaBr3 Scintillation Radiation Detectors

    SciTech Connect (OSTI)

    McGregor, Douglas S

    2011-05-01

    The objective is to develop advanced materials for deployment as high-resolution gamma ray detectors. Both LaBr3 and CeBr3 are advanced scintillation materials, and will be studied in this research. Prototype devices, in collaboration Sandia National Laboratories, will be demonstrated along with recommendations for mass production and deployment. It is anticipated that improved methods of crystal growth will yield larger single crystals of LaBr3 for deployable room-temperature operated gamma radiation spectrometers. The growth methods will be characterized. The LaBr3 and CeBr3 scintillation crystals will be characterized for light yield, spectral resolution, and for hardness.

  13. Reversible micromachining locator

    DOE Patents [OSTI]

    Salzer, Leander J. (Los Alamos, NM); Foreman, Larry R. (Los Alamos, NM)

    1999-01-01

    This invention provides a device which includes a locator, a kinematic mount positioned on a conventional tooling machine, a part carrier disposed on the locator and a retainer ring. The locator has disposed therein a plurality of steel balls, placed in an equidistant position circumferentially around the locator. The kinematic mount includes a plurality of magnets which are in registry with the steel balls on the locator. In operation, a blank part to be machined is placed between a surface of a locator and the retainer ring (fitting within the part carrier). When the locator (with a blank part to be machined) is coupled to the kinematic mount, the part is thus exposed for the desired machining process. Because the locator is removably attachable to the kinematic mount, it can easily be removed from the mount, reversed, and reinserted onto the mount for additional machining. Further, the locator can likewise be removed from the mount and placed onto another tooling machine having a properly aligned kinematic mount. Because of the unique design and use of magnetic forces of the present invention, positioning errors of less than 0.25 micrometer for each machining process can be achieved.

  14. Reversible micromachining locator

    DOE Patents [OSTI]

    Salzer, L.J.; Foreman, L.R.

    1999-08-31

    This invention provides a device which includes a locator, a kinematic mount positioned on a conventional tooling machine, a part carrier disposed on the locator and a retainer ring. The locator has disposed therein a plurality of steel balls, placed in an equidistant position circumferentially around the locator. The kinematic mount includes a plurality of magnets which are in registry with the steel balls on the locator. In operation, a blank part to be machined is placed between a surface of a locator and the retainer ring (fitting within the part carrier). When the locator (with a blank part to be machined) is coupled to the kinematic mount, the part is thus exposed for the desired machining process. Because the locator is removably attachable to the kinematic mount, it can easily be removed from the mount, reversed, and reinserted onto the mount for additional machining. Further, the locator can likewise be removed from the mount and placed onto another tooling machine having a properly aligned kinematic mount. Because of the unique design and use of magnetic forces of the present invention, positioning errors of less than 0.25 micrometer for each machining process can be achieved. 7 figs.

  15. Natural Organobromine in Marine Sediments: New Evidence of Biogeochemical Br Cycling

    SciTech Connect (OSTI)

    A Leri; J Hakala; M Marcus; A Lanzirotti; C Reddy; S Myneni

    2011-12-31

    Organobromine (Br{sub org}) compounds, commonly recognized as persistent, toxic anthropogenic pollutants, are also produced naturally in terrestrial and marine systems. Several enzymatic and abiotic bromination mechanisms have been identified, as well as an array of natural Br{sub org} molecules associated with various marine organisms. The fate of the carbon-bromine functionality in the marine environment, however, remains largely unexplored. Oceanographic studies have noted an association between bromine (Br) and organic carbon (C{sub org}) in marine sediments. Even so, there has been no direct chemical evidence that Br in the sediments exists in a stable form apart from inorganic bromide (Br{sub inorg}), which is widely presumed conservative in marine systems. To investigate the scope of natural Br{sub org} production and its fate in the environment, we probed Br distribution and speciation in estuarine and marine sediments using in situ X-ray spectroscopy and spectromicroscopy. We show that Br{sub org} is ubiquitous throughout diverse sedimentary environments, occurring in correlation with C{sub org} and metals such as Fe, Ca, and Zn. Analysis of sinking particulate carbon from the seawater column links the Br{sub org} observed in sediments to biologically produced Br{sub org} compounds that persist through humification of natural organic matter (NOM). Br speciation varies with sediment depth, revealing biogeochemical cycling of Br between organic and inorganic forms as part of the burial and degradation of NOM. These findings illuminate the chemistry behind the association of Br with Corg in marine sediments and cast doubt on the paradigmatic classification of Br as a conservative element in seawater systems.

  16. Novel visible-light AgBr/Ag?PO? hybrids photocatalysts with surface plasma resonance effects

    SciTech Connect (OSTI)

    Wang, Yunfang Li, Xiuli; Wang, Yawen; Fan, Caimei

    2013-06-01

    Three kinds of AgBr/Ag?PO? hybrids were synthesised via an anion-exchange precipitation method and characterised by XRD, XPS, SEM, EDS, and UVvis. The results showed that AgBr/Ag?PO? hybrids displayed much higher photocatalytic activities than single Ag?PO? or AgBr under visible light (?>420 nm), and OH and h? were the major active species during the degradation process. Considering interstitial ions Ag?? on lattice gap of AgBr are easy to become sliver particle, we deduced the possible photocatalytic mechanism could be ascribed to the synergistic effects of the appropriate valence band position of Ag?PO? and AgBr, surface plasmon resonance effect of Ag?, reactive radical species Br?, and the Ag vacancy on the surface of catalysts. - Graphical abstract: The optical absorption and structural morphology of the as-prepared AgBr@Ag?PO? photocatalyst using an anion-exchange precipitation method are conductive to the photocatalytic degradation of organics in water. Highlights: Novel AgBr/Ag?PO? hybrids are synthesised by a facile method. AgBr/Ag?PO? hybrids show excellent photocatalytic activities under visible light. Interstitial ions are in favour of the formation of Ag particle. Surface plasmon resonance effect plays a key factor for light absorption. The photocatalytic mechanism for AgBr/Ag?PO? hybrids is studied.

  17. Supercritical fluid reverse micelle separation

    DOE Patents [OSTI]

    Fulton, J.L.; Smith, R.D.

    1993-11-30

    A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W[sub o] that determines the maximum size of the reverse micelles. The maximum ratio W[sub o] of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions. 27 figures.

  18. Supercritical fluid reverse micelle separation

    DOE Patents [OSTI]

    Fulton, John L. (Richland, WA); Smith, Richard D. (Richland, WA)

    1993-01-01

    A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W.sub.o that determines the maximum size of the reverse micelles. The maximum ratio W.sub.o of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions.

  19. Apparatus for improving the working time of the XeBr laser

    DOE Patents [OSTI]

    Sander, Robert K. (Los Alamos, MN); Balog, George (Los Alamos, MN); Seegmiller, Emma T. (Los Alamos, MN)

    1982-01-01

    In XeBr lasers which make use of HBr as the source of bromine, it has been found that the working life of the laser is limited because of dissociation of the HBr in the lasing region to form H.sub.2 and Br.sub.2. Accordingly, apparatus is disclosed for substantially improving the working time of the XeBr laser wherein means are provided for recombining H.sub.2 and Br.sub.2 into HBr and for continuously circulating the gaseous working medium from the lasing region through the recombination region. BACKGROUND OF THE INVENTION

  20. Apparatus for improving the working time of the XeBr laser

    DOE Patents [OSTI]

    Sander, R.K.; Balog, G.; Seegmiller, E.T.

    1980-03-04

    In XeBr lasers which make use of HBr as the source of bromine, it has been found that the working life of the laser is limited because of dissociation of the HBr in the lasing region to form H/sub 2/ and Br/sub 2/. Accordingly, apparatus is disclosed for substantially improving the working time of the XeBr laser wherein means are provided for recombining H/sub 2/ and Br/sub 2/ into HBr and for continuously circulating the gaseous working medium from the lasing region through the recombination region.

  1. X-ray photoemission analysis of chemically modified TlBr surfaces for improved radiation detectors

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

    Nelson, A. J.; Voss, L. F.; Beck, P. R.; Graff, R. T.; Conway, A. M.; Nikolic, R. J.; Payne, S. A.; Lee, J. -S.; Kim, H.; Cirignano, L.; et al

    2013-01-12

    We subjected device-grade TlBr to various chemical treatments used in room temperature radiation detector fabrication to determine the resulting surface composition and electronic structure. As-polished TlBr was treated separately with HCl, SOCl2, Br:MeOH and HF solutions. High-resolution photoemission measurements on the valence band electronic structure and Tl 4f, Br 3d, Cl 2p and S 2p core lines were used to evaluate surface chemistry and shallow heterojunction formation. Surface chemistry and valence band electronic structure were correlated with the goal of optimizing the long-term stability and radiation response.

  2. Rotation Reversal Bifurcation and Energy Confinement Saturation...

    Office of Scientific and Technical Information (OSTI)

    Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak OhmicL-Mode Plasmas Citation Details In-Document Search Title: Rotation Reversal Bifurcation and Energy...

  3. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Direct Imaging of Asymmetric Magnetization Reversal Print Wednesday, 28 September 2005 00:00 The phenomenon of exchange bias has...

  4. Chemically homogeneous and thermally reversible oxidation of...

    Office of Scientific and Technical Information (OSTI)

    Chemically homogeneous and thermally reversible oxidation of epitaxial graphene Citation Details In-Document Search Title: Chemically homogeneous and thermally reversible oxidation ...

  5. Performance of LiAlloy/Ag(2)CrO(4) Couples in Molten CsBr-LiBr-KBr Eutectic

    SciTech Connect (OSTI)

    GUIDOTTI,RONALD A.; REINHARDT,FREDERICK W.

    1999-10-18

    The performance of Li-alloy/CsBr-LiBr-KBr/Ag{sub 2}CrO{sub 4} systems was studied over a temperature range of 250 C to 300 C, for possible use as a power source for geothermal borehole applications. Single cells were discharged at current densities of 15.8 and 32.6 mA/cm{sup 2} using Li-Si and Li-Al anodes. When tested in 5-cell batteries, the Li-Si/CsBr-LiBr-KBr/Ag{sub 2}CrO{sub 4} system exhibited thermal runaway. Thermal analytical tests showed that the Ag{sub 2}CrO{sub 4} cathode reacted exothermically with the electrolyte on activation. Consequently, this system would not be practical for the envisioned geothermal borehole applications.

  6. Results for aliovalent doping of CeBr{sub 3} with Ca{sup 2+}

    SciTech Connect (OSTI)

    Guss, Paul; Foster, Michael E.; Wong, Bryan M.; Patrick Doty, F.; Shah, Kanai; Squillante, Michael R.; Shirwadkar, Urmila; Hawrami, Rastgo; Tower, Joshua; Yuan, Ding

    2014-01-21

    Despite the outstanding scintillation performance characteristics of cerium tribromide (CeBr{sub 3}) and cerium-activated lanthanum tribromide, their commercial availability and application are limited due to the difficulties of growing large, crack-free single crystals from these fragile materials. This investigation employed aliovalent doping to increase crystal strength while maintaining the optical properties of the crystal. One divalent dopant (Ca{sup 2+}) was used as a dopant to strengthen CeBr{sub 3} without negatively impacting scintillation performance. Ingots containing nominal concentrations of 1.9% of the Ca{sup 2+} dopant were grown, i.e., 1.9% of the CeBr{sub 3} molecules were replaced by CaBr{sub 2} molecules, to match our target replacement of 1 out of 54 cerium atoms be replaced by a calcium atom. Precisely the mixture was composed of 2.26 g of CaBr{sub 2} added to 222.14 g of CeBr{sub 3}. Preliminary scintillation measurements are presented for this aliovalently doped scintillator. Ca{sup 2+}-doped CeBr{sub 3} exhibited little or no change in the peak fluorescence emission for 371?nm optical excitation for CeBr{sub 3}. The structural, electronic, and optical properties of CeBr{sub 3} crystals were studied using the density functional theory within the generalized gradient approximation. Calculated lattice parameters are in agreement with the experimental data. The energy band structures and density of states were obtained. The optical properties of CeBr{sub 3}, including the dielectric function, were calculated.

  7. Characterization of the LiSi/CsBr-LiBr-KBr/FeS(2) System for Potential Use as a Geothermal Borehole Power Source

    SciTech Connect (OSTI)

    GUIDOTTI, RONALD A.; REINHARDT, FREDERICK W.

    1999-10-18

    We are continuing to study the suitability of modified thermal-battery technology as a potential power source for geothermal borehole applications. Previous work focused on the LiSi/FeS{sub 2} couple over a temperature range of 350 C to 400 C with the LiBr-KBr-LiF eutectic, which melts at 324.5 C. In this work, the discharge processes that take place in LiSi/CsBr-LiBr-KBr eutectic/FeS{sub 2} thermal cells were studied at temperatures between 250 C and 400 C using pelletized cells with immobilized electrolyte. The CsBr-LiBr-KBr eutectic was selected because of its lower melting point (228.5 C). Incorporation of a quasi-reference electrode allowed the determination of the relative contribution of each electrode to the overall cell polarization. The results of single-cell tests and limited battery tests are presented, along with preliminary data for battery stacks tested in a simulated geothermal borehole environment.

  8. Studies on Ca2+-Doped CeBr3 Scintillating Materials

    SciTech Connect (OSTI)

    Guss, P. [NSTec; Foster, M. E. [SNL; Wong, B. M. [SNL; Doty, F. P. [SNL; Shah, K. [RMD; Squillante, M. [RMD; Glodo, J. [RMD; Yuan, D. [NSTec

    2013-07-03

    Despite the outstanding scintillation performance characteristics of cerium tribromide (CeBr3) and cerium-activated lanthanum tribromide (LaBr3:Ce), their commercial availability and application is limited due to the difficulties of growing large, crack-free single crystals from these fragile materials. The objective of this investigation was to employ aliovalent doping to increase crystal strength while maintaining the optical properties of the crystal. One divalent dopant (Ca2+) was investigated as a dopant to strengthen CeBr3 without negatively impacting scintillation performance. Ingots containing nominal concentrations of 1.9% of the Ca2+ dopant were grown. Preliminary scintillation measurements are presented for this aliovalently doped scintillator. Ca2+-doped CeBr3 exhibited little or no change in the peak fluorescence emission for 371 nm optical excitation for CeBr3. The structural, electronic, and optical properties of CeBr3 crystals were investigated using the density functional theory within generalized gradient approximation. The calculated lattice parameters are in good agreement with the experimental data. The energy band structures and density of states were obtained. The optical properties of CeBr3, including the dielectric function, were calculated.

  9. Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP

    Office of Environmental Management (EM)

    Applications, April 2005 | Department of Energy Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 The objective of this paper is to summarize the development status of air-cooled lithium bromide (LiBr)-water absorption chillers to guide future efforts to develop chillers for combined heat and power (CHP) applications in light-commercial buildings. The key

  10. Reverse engineering of integrated circuits

    DOE Patents [OSTI]

    Chisholm, Gregory H. (Shorewood, IL); Eckmann, Steven T. (Colorado Springs, CO); Lain, Christopher M. (Pittsburgh, PA); Veroff, Robert L. (Albuquerque, NM)

    2003-01-01

    Software and a method therein to analyze circuits. The software comprises several tools, each of which perform particular functions in the Reverse Engineering process. The analyst, through a standard interface, directs each tool to the portion of the task to which it is most well suited, rendering previously intractable problems solvable. The tools are generally used iteratively to produce a successively more abstract picture of a circuit, about which incomplete a priori knowledge exists.

  11. Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface...

    Office of Scientific and Technical Information (OSTI)

    Title: OxidationReduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Authors: Nelson, A J ; Swanberg, E L ; Voss, L F ; Graff, R T ; ...

  12. Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface...

    Office of Scientific and Technical Information (OSTI)

    Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Citation Details In-Document Search Title: OxidationReduction Reactions at...

  13. Remote Whispering Applying Time Reversal

    SciTech Connect (OSTI)

    Anderson, Brian Eric

    2015-07-16

    The purpose of this project was to explore the use of time reversal technologies as a means for communication to a targeted individual or location. The idea is to have the privacy of whispering in one’s ear, but to do this remotely from loudspeakers not located near the target. Applications of this work include communicating with hostages and survivors in rescue operations, communicating imaging and operational conditions in deep drilling operations, monitoring storage of spent nuclear fuel in storage casks without wires, or clandestine activities requiring signaling between specific points. This technology provides a solution in any application where wires and radio communications are not possible or not desired. It also may be configured to self calibrate on a regular basis to adjust for changing conditions. These communications allow two people to converse with one another in real time, converse in an inaudible frequency range or medium (i.e. using ultrasonic frequencies and/or sending vibrations through a structure), or send information for a system to interpret (even allowing remote control of a system using sound). The time reversal process allows one to focus energy to a specific location in space and to send a clean transmission of a selected signal only to that location. In order for the time reversal process to work, a calibration signal must be obtained. This signal may be obtained experimentally using an impulsive sound, a known chirp signal, or other known signals. It may also be determined from a numerical model of a known environment in which the focusing is desired or from passive listening over time to ambient noise.

  14. Measurement of BR(Bu to phi K)/BR(Bu to J/psi K) at the collider detector at Fermilab

    SciTech Connect (OSTI)

    Napora, Robert A

    2004-10-01

    This thesis presents evidence for the decay mode B{sup {+-}} {yields} {phi}K{sup {+-}} in p{bar p} collisions at {radical}s = 1.96 TeV using (120 {+-} 7)pb{sup -1} of data collected by the Collider Detector at Fermilab (CDF). This signal is then used to measure the branching ratio relative to the decay mode B{sup {+-}} {yields} J/{psi}K{sup {+-}}. The measurement starts from reconstructing the two decay modes: B{sup {+-}} {yields} {phi}K{sup {+-}}, where {phi} {yields} K{sup +}K{sup -} and B{sup {+-}} {yields} J/{psi}K{sup {+-}}, where J/{psi} {yields} {mu}{sup +}{mu}{sup -}. The measurement yielded 23 {+-} 7 B{sup {+-}} {yields} {phi}K{sup {+-}} events, and 406 {+-} 26 B{sup {+-}} {yields} J/{psi}K{sup {+-}} events. The fraction of B{sup {+-}} {yields} J/{psi}K{sup {+-}} events where the J/{psi} subsequently decayed to two muons (as opposed to two electrons) was found to be f{sub {mu}{mu}} = 0.839 {+-} 0.066. The relative branching ratio of the two decays is then calculated based on the equation: BR(B{sup {+-}} {yields} {phi}K{sup {+-}})/BR(B{sup {+-}} {yields} J/{psi}K{sup {+-}}) = N{sub {phi}K}/N{sub {psi}K} {center_dot}f{sub {mu}{mu}} BR(J/{psi} {yields} {mu}{sup +}{mu}{sup -})/BR({phi} {yields} K{sup +}K{sup -}) {epsilon}{sub {mu}{mu}}K/{epsilon}KKK R({epsilon}{sub iso}). The measurement finds BR(B{sup {+-}} {yields} {phi}K{sup {+-}})/BR(B{sup {+-}} {yields} J/{psi}K{sup {+-}}) = 0.0068 {+-} 0.0021(stat.) {+-} 0.0007(syst.). The B{sup {+-}} {yields} {phi}K{sup {+-}} branching ratio is then found to be BR(B{sup {+-}} {yields} {phi}K{sup {+-}}) = [6.9 {+-} 2.1(stat.) {+-} 0.8(syst.)] x 10{sup -6}. This value is consistent with similar measurements reported by the e{sup +}e{sup -} collider experiments BaBar[1], Belle[2], and CLEO[3].

  15. Gravity controlled anti-reverse rotation device

    DOE Patents [OSTI]

    Dickinson, Robert J. (Shaler Township, Allegheny County, PA); Wetherill, Todd M. (Lower Burrell, PA)

    1983-01-01

    A gravity assisted anti-reverse rotation device for preventing reverse rotation of pumps and the like. A horizontally mounted pawl is disposed to mesh with a fixed ratchet preventing reverse rotation when the pawl is advanced into intercourse with the ratchet by a vertically mounted lever having a lumped mass. Gravitation action on the lumped mass urges the pawl into mesh with the ratchet, while centrifugal force on the lumped mass during forward, allowed rotation retracts the pawl away from the ratchet.

  16. Time Reversal of Bose-Einstein Condensates

    SciTech Connect (OSTI)

    Martin, J.; Georgeot, B.; Shepelyansky, D. L. [Laboratoire de Physique Theorique, Universite de Toulouse III, CNRS, 31062 Toulouse (France)

    2008-08-15

    Using Gross-Pitaevskii equation, we study the time reversibility of Bose-Einstein condensates (BEC) in kicked optical lattices, showing that in the regime of quantum chaos, the dynamics can be inverted from explosion to collapse. The accuracy of time reversal decreases with the increase of atom interactions in BEC, until it is completely lost. Surprisingly, quantum chaos helps to restore time reversibility. These predictions can be tested with existing experimental setups.

  17. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Direct Imaging of Asymmetric Magnetization Reversal Print Wednesday, 28 September 2005 00:00 The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron

  18. Reverse Osmosis Optimization | Department of Energy

    Energy Savers [EERE]

    Reverse Osmosis Optimization Reverse Osmosis Optimization Report assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. It provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. This report is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system

  19. Rotation Reversal Bifurcation and Energy Confinement Saturation...

    Office of Scientific and Technical Information (OSTI)

    Title: Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L ... Publication Date: 2011-12-20 OSTI Identifier: 1098456 Type: Publisher's Accepted ...

  20. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their...

  1. Very fast doped LaBr.sub.3 scintillators and time-of-flight PET

    DOE Patents [OSTI]

    Shah, Kanai S.

    2006-10-31

    The present invention concerns very fast scintillator materials capable of resolving the position of an annihilation event within a portion of a human body cross-section. In one embodiment, the scintillator material comprises LaBr.sub.3 doped with cerium. Particular attention is drawn to LaBr.sub.3 doped with a quantity of Ce that is chosen for improving the timing properties, in particular the rise time and resultant timing resolution of the scintillator, and locational capabilities of the scintillator.

  2. Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray

    Office of Scientific and Technical Information (OSTI)

    Photoelectron Spectroscopy Study (Conference) | SciTech Connect Conference: Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Citation Details In-Document Search Title: Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Authors: Nelson, A J ; Swanberg, E L ; Voss, L F ; Graff, R T ; Conway, A M ; Nikolic, R J ; Payne, S A ; Kim, H ; Cirignano, L ; Shah, K Publication Date:

  3. Lattice dynamics in perovskite halides CsSn X 3 with X = I , Br , Cl

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Lattice dynamics in perovskite halides CsSn X 3 with X = I , Br , Cl Citation Details In-Document Search Title: Lattice dynamics in perovskite halides CsSn X 3 with X = I , Br , Cl Authors: Huang, Ling-yi ; Lambrecht, Walter R. L. Publication Date: 2014-11-05 OSTI Identifier: 1180124 Grant/Contract Number: ER 46874-SC0008933 Type: Publisher's Accepted Manuscript Journal Name: Physical Review B Additional Journal Information: Journal Volume: 90; Journal

  4. LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON

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

    81 § ¨ ¦ 81 LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON CALEDONIA HURON C REEK LEIC EST ER COL DEN ASH FORD INDIAN FALLS LAWTONS SAR DINIA RPD-037 -2 GLENWOOD PU LASKI PAVILION CON CORD COL LINS N ELM A ORC HARD PARK-H AMBU RG DANLEY CORNERS ST ILLWAT ER CHAFF EE-ARCAD E FAYETT E-WATERLOO LAKEVIEW JAVA SEN EC A W ELLER Y AU RORA E ZOAR BU FFALO TIOGA SILVER LAKE AKR ON ROM E RAT HBON E ALM A BET HANY WYOMING ULYSSES BR ANCH W SAN DY CREEK COL LINS BLOOMFIELD E LEBANON

  5. Fuel cell system with coolant flow reversal

    DOE Patents [OSTI]

    Kothmann, Richard E. (Pittsburgh, PA)

    1986-01-01

    Method and apparatus for cooling electrochemical fuel cell system components. Periodic reversal of the direction of flow of cooling fluid through a fuel cell stack provides greater uniformity and cell operational temperatures. Flow direction through a recirculating coolant fluid circuit is reversed through a two position valve, without requiring modulation of the pumping component.

  6. CALiPER Application Summary Report 16. LED BR30 and R30 Lamps

    SciTech Connect (OSTI)

    none,

    2012-07-01

    This report analyzes the independently tested performance of 13 LED products labeled as BR30 or R30 lamps. The test results indicate substantial improvement versus earlier CALiPER testing of similar products, and performance comparable to recent data from LED Lighting Facts and ENERGY STAR.

  7. Brønsted Acidity in Metal-Organic Frameworks | Center for Gas

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

    SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Brønsted Acidity in Metal-Organic Frameworks Previous Next List Jiang, Juncong and Yaghi, Omar, M. Bronsted Acidity in Metal-Organic Frameworks. Chem. Rev., 115, 6966-6997 (2015). DOI: 10.1021/acs.chemrev.5b00221 Bronsted Acidity in MOFs

  8. Chemical reactions in reverse micelle systems

    DOE Patents [OSTI]

    Matson, Dean W. (Kennewick, WA); Fulton, John L. (Richland, WA); Smith, Richard D. (Richland, WA); Consani, Keith A. (Richland, WA)

    1993-08-24

    This invention is directed to conducting chemical reactions in reverse micelle or microemulsion systems comprising a substantially discontinuous phase including a polar fluid, typically an aqueous fluid, and a microemulsion promoter, typically a surfactant, for facilitating the formation of reverse micelles in the system. The system further includes a substantially continuous phase including a non-polar or low-polarity fluid material which is a gas under standard temperature and pressure and has a critical density, and which is generally a water-insoluble fluid in a near critical or supercritical state. Thus, the microemulsion system is maintained at a pressure and temperature such that the density of the non-polar or low-polarity fluid exceeds the critical density thereof. The method of carrying out chemical reactions generally comprises forming a first reverse micelle system including an aqueous fluid including reverse micelles in a water-insoluble fluid in the supercritical state. Then, a first reactant is introduced into the first reverse micelle system, and a chemical reaction is carried out with the first reactant to form a reaction product. In general, the first reactant can be incorporated into, and the product formed in, the reverse micelles. A second reactant can also be incorporated in the first reverse micelle system which is capable of reacting with the first reactant to form a product.

  9. Cheaper Adjoints by Reversing Address Computations

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

    Hascoët, L.; Utke, J.; Naumann, U.

    2008-01-01

    The reverse mode of automatic differentiation is widely used in science and engineering. A severe bottleneck for the performance of the reverse mode, however, is the necessity to recover certain intermediate values of the program in reverse order. Among these values are computed addresses, which traditionally are recovered through forward recomputation and storage in memory. We propose an alternative approach for recovery that uses inverse computation based on dependency information. Address storage constitutes a significant portion of the overall storage requirements. An example illustrates substantial gains that the proposed approach yields, and we show use cases in practical applications.

  10. Direct Imaging of Asymmetric Magnetization Reversal

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

    and H. Ohldag, "Direct imaging of asymmetric magnetization reversal in exchange-biased FeMnPd bilayers by x-ray photoemission electron microscopy," Phys. Rev. Lett. 94, 107203...

  11. Direct Imaging of Asymmetric Magnetization Reversal

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

    H. Ohldag, "Direct imaging of asymmetric magnetization reversal in exchange-biased FeMnPd bilayers by x-ray photoemission electron microscopy," Phys. Rev. Lett. 94, 107203 (2005...

  12. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in...

  13. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Reversing the Circulation of Magnetic Vortices Print Wednesday, 31 July 2013 00:00 In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny

  14. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  15. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  16. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  17. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  18. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  19. Geothermal br Resource br Area Geothermal br Resource br Area...

    Open Energy Info (EERE)

    Aluto Langano Geothermal Area Aluto Langano Geothermal Area East African Rift System Ethiopian Rift Valley Major Normal Fault Basalt MW K Amatitlan Geothermal Area Amatitlan...

  20. Fractional Topological Phases and Broken Time-Reversal Symmetry...

    Office of Scientific and Technical Information (OSTI)

    Fractional Topological Phases and Broken Time-Reversal Symmetry in Strained Graphene Prev Next Title: Fractional Topological Phases and Broken Time-Reversal Symmetry in...

  1. Reversible ratchet effects for vortices in conformal pinning...

    Office of Scientific and Technical Information (OSTI)

    Reversible ratchet effects for vortices in conformal pinning arrays Citation Details In-Document Search This content will become publicly available on May 3, 2016 Title: Reversible...

  2. Reverse phase transformation of martensite to austenite in stainless...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Reverse phase transformation of martensite to austenite in stainless steels: a 3D phase-field study Citation Details In-Document Search Title: Reverse phase...

  3. Investigation into Nanostructured Lanthanum Halides and CeBr{sub 3} for Nuclear Radiation Detection

    SciTech Connect (OSTI)

    Guss, P., Guise, R., Mukhopadhyay, S., Yuan, D.

    2011-06-22

    This slide-show presents work on radiation detection with nanostructured lanthanum halides and CeBr{sub 3}. The goal is to extend the gamma energy response on both low and high-energy regimes by demonstrating the ability to detect low-energy x-rays and relatively high-energy activation prompt gamma rays simultaneously using the nano-structured lanthanum bromide, lanthanum fluoride, cerium bromide, or other nanocrystal material. Homogeneous and nano structure cases are compared.

  4. A modified Stillinger-Weber potential for TlBr and its polymorphic extension

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

    Zhou, Xiaowang; Foster, Michael E.; Jones, Reese E.; Doty, F. Patrick; Yang, Pin; Fan, Hongyou

    2015-04-30

    TlBr is promising for g- and x- radiation detection, but suffers from rapid performance degradation under the operating external electric fields. To enable molecular dynamics (MD) studies of this degradation, we have developed a Stillinger-Weber type of TlBr interatomic potential. During this process, we have also addressed two problems of wider interests. First, the conventional Stillinger-Weber potential format is only applicable for tetrahedral structures (e.g., diamond-cubic, zinc-blende, or wurtzite). Here we have modified the analytical functions of the Stillinger-Weber potential so that it can now be used for other crystal structures. Second, past modifications of interatomic potentials cannot always bemore » applied by a broad community because any new analytical functions of the potential would require corresponding changes in the molecular dynamics codes. Here we have developed a polymorphic potential model that simultaneously incorporates Stillinger-Weber, Tersoff, embedded-atom method, and any variations (i.e., modified functions) of these potentials. As a result, we have implemented this polymorphic model in MD code LAMMPS, and demonstrated that our TlBr potential enables stable MD simulations under external electric fields.« less

  5. Response of LaBr{sub 3}(Ce) scintillators to 2.5 MeV fusion neutrons

    SciTech Connect (OSTI)

    Cazzaniga, C.; Nocente, M.; Gorini, G.; Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Via Roberto Cozzi 53, Milano 20125 ; Tardocchi, M.; Croci, G.; Giacomelli, L.; Angelone, M.; Pillon, M.; Villari, S.; Weller, A.; Petrizzi, L.; Collaboration: ASDEX Upgrade Team; JET-EFDA Contributors

    2013-12-15

    Measurements of the response of LaBr{sub 3}(Ce) to 2.5 MeV neutrons have been carried out at the Frascati Neutron Generator and at tokamak facilities with deuterium plasmas. The observed spectrum has been interpreted by means of a Monte Carlo model. It is found that the main contributor to the measured response is neutron inelastic scattering on {sup 79}Br, {sup 81}Br, and {sup 139}La. An extrapolation of the count rate response to 14 MeV neutrons from deuterium-tritium plasmas is also presented. The results are of relevance for the design of ?-ray diagnostics of fusion burning plasmas.

  6. Characterization of low-melting electrolytes for potential geothermal borehole power supplies: The LiBr-KBr-LiF eutectic

    SciTech Connect (OSTI)

    Guidotti, R.A.; Reinhardt, F.W.

    1998-05-01

    The suitability of modified thermal-battery technology for use as a potential power source for geothermal borehole applications is under investigation. As a first step, the discharge processes that take place in LiSi/LiBr-KBr-LiF/FeS{sub 2} thermal cells were studied at temperatures of 350 C and 400 C using pelletized cells with immobilized electrolyte. Incorporation of a reference electrode allowed the relative contribution of each electrode to the overall cell polarization to be determined. The results of single-cell tests are presented, along with preliminary data for cells based on a lower-melting CsBr-LiBr-KBr eutectic salt.

  7. Optimal design of reverse osmosis module networks

    SciTech Connect (OSTI)

    Maskan, F.; Wiley, D.E.; Johnston, L.P.M.; Clements, D.J.

    2000-05-01

    The structure of individual reverse osmosis modules, the configuration of the module network, and the operating conditions were optimized for seawater and brackish water desalination. The system model included simple mathematical equations to predict the performance of the reverse osmosis modules. The optimization problem was formulated as a constrained multivariable nonlinear optimization. The objective function was the annual profit for the system, consisting of the profit obtained from the permeate, capital cost for the process units, and operating costs associated with energy consumption and maintenance. Optimization of several dual-stage reverse osmosis systems were investigated and compared. It was found that optimal network designs are the ones that produce the most permeate. It may be possible to achieve economic improvements by refining current membrane module designs and their operating pressures.

  8. Time reversal signal processing for communication.

    SciTech Connect (OSTI)

    Young, Derek P.; Jacklin, Neil; Punnoose, Ratish J.; Counsil, David T.

    2011-09-01

    Time-reversal is a wave focusing technique that makes use of the reciprocity of wireless propagation channels. It works particularly well in a cluttered environment with associated multipath reflection. This technique uses the multipath in the environment to increase focusing ability. Time-reversal can also be used to null signals, either to reduce unintentional interference or to prevent eavesdropping. It does not require controlled geometric placement of the transmit antennas. Unlike existing techniques it can work without line-of-sight. We have explored the performance of time-reversal focusing in a variety of simulated environments. We have also developed new algorithms to simultaneously focus at a location while nulling at an eavesdropper location. We have experimentally verified these techniques in a realistic cluttered environment.

  9. Transport Physics in Reversed Shear Plasmas

    SciTech Connect (OSTI)

    Levinton, F.M.; Batha, S.H.; Beer, M.A.; Bell, M.G.; Budny, R.V.; Efthimion, P.C.; Mazzucato, E.; Nazikian, R.; Park, H.K.; Ramsey, A.T.; Schmidt, G.L.; Scott, S.D.; Synakowski, E.J.; Taylor, G.; Von Goeler, S.; Zarnstorff, M.C.; Bush, C.E.

    1997-12-31

    Reversed magnetic shear is considered a good candidate for improving the tokamak concept because it has the potential to stabilize MHD instabilities and reduce particle and energy transport. With reduced transport the high pressure gradient would generate a strong off-axis bootstrap current and could sustain a hollow current density profile. Such a combination of favorable conditions could lead to an attractive steady-state tokamak configuration. Indeed, a new tokamak confinement regime with reversed magnetic shear has been observed on the Tokamak Fusion Test Reactor (TFTR) where the particle, momentum, and ion thermal diffusivities drop precipitously, by over an order of magnitude. The particle diffusivity drops to the neoclassical level and the ion thermal diffusivity drops to much less than the neoclassical value in the region with reversed shear. This enhanced reversed shear (ERS) confinement mode is characterized by an abrupt transition with a large rate of rise of the density in the reversed shear region during neutral beam injection, resulting in nearly a factor of three increase in the central density to 1.2 X 10(exp 20) cube m. At the same time the density fluctuation level in the reversed shear region dramatically decreases. The ion and electron temperatures, which are about 20 keV and 7 keV respectively, change little during the ERS mode. The transport and transition into and out of the ERS mode have been studied on TFTR with plasma currents in the range 0.9-2.2 MA, with a toroidal magnetic field of 2.7-4.6 T, and the radius of the q(r) minimum, q{sub min}, has been varied from r/a = 0.35 to 0.55. Toroidal field and co/counter neutral beam injection toroidal rotation variations have been used to elucidate the underlying physics of the transition mechanism and power threshold of the ERS mode.

  10. Reversible Fuel Cells Workshop Summary Report | Department of Energy

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

    Reversible Fuel Cells Workshop Summary Report Reversible Fuel Cells Workshop Summary Report Summary and presentations from the NREL Reversible Fuel Cells Workshop held April 19, 2011 PDF icon rev_fc_wkshp_report.pdf More Documents & Publications Lessons Learned from SOFC/SOEC Development Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Development of Reversible Fuel Cell Systems at Proton Energy

  11. Forward and reverse characteristics of irradiated MOSFETs

    SciTech Connect (OSTI)

    Paccagnella, A.; Ceschia, M.; Verzellesi, G.; Dalla Betta, G.F.; Soncini, G.; Bellutti, P.; Fuochi, P.G.

    1996-06-01

    pMOSFETs biased with V{sub gs} < V{sub gd} during Co{sup 60} {gamma} irradiation have shown substantial differences between the forward and reverse subthreshold characteristics, induced by a non-uniform charge distribution in the gate oxide. Correspondingly, modest differences have been observed in the over-threshold I-V characteristics. After irradiation, the forward subthreshold curves can shift at higher or lower gate voltages than the reverse ones. The former behavior has been observed in long-channel devices, in agreement with the classical MOS theory and numerical simulations. The latter result has been obtained in short-channel devices, and it has been correlated to a parasitic punch-through conduction mechanism.

  12. Reversible Sigma C-C Bond Formation Between Phenanthroline Ligands...

    Office of Scientific and Technical Information (OSTI)

    Reversible Sigma C-C Bond Formation Between Phenanthroline Ligands Activated by (C5Me5)2Yb Citation Details In-Document Search Title: Reversible Sigma C-C Bond Formation Between ...

  13. High temperature crystal structures and superionic properties of SrCl{sub 2}, SrBr{sub 2}, BaCl{sub 2} and BaBr{sub 2}

    SciTech Connect (OSTI)

    Hull, Stephen; Norberg, Stefan T.; Ahmed, Istaq; Eriksson, Sten G.; Mohn, Chris E.

    2011-11-15

    The structural properties of the binary alkaline-earth halides SrCl{sub 2}, SrBr{sub 2}, BaCl{sub 2} and BaBr{sub 2} have been investigated from ambient temperature up to close to their melting points, using the neutron powder diffraction technique. Fluorite-structured SrCl{sub 2} undergoes a gradual transition to a superionic phase at 900-1100 K, characterised by an increasing concentration of anion Frenkel defects. At a temperature of 920(3) K, the tetragonal phase of SrBr{sub 2} undergoes a first-order transition to a cubic fluorite phase. This high temperature phase shows the presence of extensive disorder within the anion sublattice, which differs from that found in superionic SrCl{sub 2}. BaCl{sub 2} and BaBr{sub 2} both adopt the cotunnite crystal structure under ambient conditions. BaCl{sub 2} undergoes a first-order structural transition at 917(5) K to a disordered fluorite-structured phase. The relationship between the (disordered) crystal structures and the ionic conductivity behaviour is discussed and the influence of the size of the mobile anion on the superionic behaviour is explored. - Graphical abstract: Anomalous behaviour of the lattice expansion of SrCl{sub 2} at temperatures of {approx}1000 K is associated with the gradual transition to a superionic phase, whilst SrBr{sub 2} undergoes a first-order structural transition ({beta}{yields}{alpha}) to a fluorite-structured superionic phase at 920(3) K. Highlights: > Anomalous behaviour of the lattice expansion of SrCl{sub 2} occurs at temperatures {approx}1000 K. > Crystal structure of {beta}-SrBr{sub 2} is described in detail. > On heating, SrBr{sub 2} and BaCl{sub 2} transform to a fluorite-structured superionic phase. > Temperature dependence of the BaCl{sub 2} and BaBr{sub 2} structures is presented. > Nature of the superionic phases within the alkaline-earth halides is discussed.

  14. Progress on the Development of Reversible SOFC Stack Technology

    Broader source: Energy.gov [DOE]

    Presentation by Casey Brown, Versa Power Systems, at the NREL Reversible Fuel Cells Workshop, April 19, 2011

  15. Development of Reversible Fuel Cell Systems at Proton Energy | Department

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

    of Energy Reversible Fuel Cell Systems at Proton Energy Development of Reversible Fuel Cell Systems at Proton Energy Presentation by Everett Anderson, PROTON ON SITE, at the NREL Reversible Fuel Cells Workshop, April 19, 2011 PDF icon rev_fc_wkshp_anderson.pdf More Documents & Publications Reversible Fuel Cells Workshop Summary Report Regenerative Fuel Cells for Energy Storage Small Business Innovation Research (SBIR) Award Success Story: Proton Energy Systems

  16. LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    DOE Patents [OSTI]

    Ko, Suk M. (Huntsville, AL)

    1980-01-01

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

  17. Time Reversal in Solids (Linear and Nonlinear Elasticity): Multimedia Resources in Time Reversal

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

    Dynamic nonlinear elastic behavior, nonequilibrium dynamics, first observed as a curiosity in earth materials has now been observed in a great variety of solids. The primary manifestations of the behavior are characteristic wave distortion, and slow dynamics, a recovery process to equilibrium that takes place linearly with the logarithm of time, over hours to days after a wave disturbance. The link between the diverse materials that exhibit nonequilibrium dynamics appears to be the presence of soft regions, thought to be 'damage' at many scales, ranging from order 10-9 m to 10-1 m at least. The regions of soft matter may be distributed as in a rock sample, or isolated, as in a sample with a single crack [LANLhttp://www.lanl.gov/orgs/ees/ees11/geophysics/nonlinear/nonlinear.shtml]. The Geophysics Group (EES-11) at Los Alamos National Laboratory has posted two or more multimedia items under each of the titles below to demonstrate aspects of their work: 1) Source Reconstruction Using Time Reversal; 2) Robustness and Efficiency of Time Reversal Acoustics in Solid Media; 3) Audio Example of Time Reversal - Speech Privacy; 4) Crack Imagining with Time Reversal - Experimental Results; 5) Time Reversal of the 2004 (M9.0) Sumatra Earthquake.

  18. X-ray-absorption study of CuBr at high pressure

    SciTech Connect (OSTI)

    Tranquada, J.M.; Ingalls, R.

    1986-09-15

    The x-ray-absorption spectrum of cuprous bromide has been measured as a function of pressure. The x-ray-absorption near-edge structure proved to be an excellent indicator of high-pressure phase transitions in this material. The normalized ''white-line'' peak heights at both the Cu and Br K-italic edges decreased on entering the tetragonal phase and increased in going to the NaCl structure. The zinc-blende to tetragonal phase transition took place over a very narrow pressure range centered at 46 +- 5 kbar. The transformation from the tetragonal to the NaCl structure, on the other hand, showed a broad mixed-phase region, suggesting a nucleation-and-growth mechanism for the transition. The mixed-phase region was centered at 75 +- 6 kbar. No evidence of a phase between the zinc-blende and tetragonal phases was observed, presumably because it does not exist. Analysis of the extended x-ray-absorption fine-structure (EXAFS) clearly showed that there is no change in coordination in going from the zinc-blende to the tetragonal phase although the nearest-neighbor distance increases slightly. A much larger increase in R-italic/sub 1/ occurs at the transition to the NaCl structure, where the coordination increases from 4 to 6. The mean-square deviation in the nearest-neighbor bond length, sigma/sub 1//sup 2/, appears to be a fairly smooth function of nearest-neighbor distance, decreasing (or increasing) as R-italic/sub 1/ decreases (or increases) more or less independent of structure. Evidence from the literature was presented to suggest that the zinc-blende to tetragonal transition in CuBr (and also CuCl) should occur by shear deformation.

  19. Molecular Characterization of Brown Carbon (BrC) Chromophores in Secondary Organic Aerosol Generated From Photo-Oxidation of Toluene

    SciTech Connect (OSTI)

    Lin, Peng; Liu, Jiumeng; Shilling, John E.; Kathmann, Shawn M.; Laskin, Julia; Laskin, Alexander

    2015-09-28

    Atmospheric Brown carbon (BrC) is a significant contributor to light absorption and climate forcing. However, little is known about a fundamental relationship between the chemical composition of BrC and its optical properties. In this work, light-absorbing secondary organic aerosol (SOA) was generated in the PNNL chamber from toluene photo-oxidation in the presence of NOx (Tol-SOA). Molecular structures of BrC components were examined using nanospray desorption electrospray ionization (nano-DESI) and liquid chromatography (LC) combined with UV/Vis spectroscopy and electrospray ionization (ESI) high-resolution mass spectrometry (HRMS). The chemical composition of BrC chromophores and the light absorption properties of toluene SOA (Tol-SOA) depend strongly on the initial NOx concentration. Specifically, Tol-SOA generated under high-NOx conditions (defined here as initial NOx/toluene of 5/1) appears yellow and mass absorption coefficient of the bulk sample (MACbulk@365nm = 0.78 m2 g-1) is nearly 80 fold higher than that measured for the Tol-SOA sample generated under low-NOx conditions (NOx/toluene < 1/300). Fifteen compounds, most of which are nitrophenols, are identified as major BrC chromophores responsible for the enhanced light absorption of Tol-SOA material produced in the presence of NOx. The integrated absorbance of these fifteen chromophores accounts for 40-60% of the total light absorbance by Tol-SOA at wavelengths between 300 nm and 500 nm. The combination of tandem LC-UV/Vis-ESI/HRMS measurements provides an analytical platform for predictive understanding of light absorption properties by BrC and their relationship to the structure of individual chromophores. General trends in the UV/vis absorption by plausible isomers of the BrC chromophores were evaluated using theoretical chemistry calculations. The molecular-level understanding of BrC chemistry is helpful for better understanding the evolution and behavior of light absorbing aerosols in the atmosphere.

  20. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  1. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  2. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  3. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  4. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  5. Kinetic Stability of the Field Reversed Configuration

    SciTech Connect (OSTI)

    E.V. Belova; R.C. Davidson; H. Ji; and M. Yamada

    2002-07-09

    New computational results are presented which advance the understanding of the stability properties of the Field-Reversed Configuration (FRC). The FRC is an innovative confinement approach that offers a unique fusion reactor potential because of its compact and simple geometry, translation properties, and high plasma beta. One of the most important issues is FRC stability with respect to low-n (toroidal mode number) MHD modes. There is a clear discrepancy between the predictions of standard MHD theory that many modes should be unstable on the MHD time scale, and the observed macroscopic resilience of FRCs in experiments.

  6. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  7. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

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

    SciTech Connect (OSTI)

    Peric, Berislav; Jozic, Drazan; Planinic, Pavica; Brnicevic, Nevenka; Giester, Gerald

    2009-09-15

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

  9. Ultrafast dynamics of strong-field dissociative ionization ofCH2Br2 probed by femtosecond soft x-ray transient absorptionspectroscopy

    SciTech Connect (OSTI)

    Loh, Zhi-Heng; Leone, Stephen R.

    2008-01-15

    Femtosecond time-resolved soft x-ray transient absorption spectroscopy based on a high-order harmonic generation source is used to investigate the dissociative ionization of CH{sub 2}Br{sub 2} induced by 800 nm strong-field irradiation. At moderate peak intensities (2.0 x 10{sup 14} W/cm{sup 2}), strong-field ionization is accompanied by ultrafast C-Br bond dissociation, producing both neutral Br ({sup 2}P{sub 3/2}) and Br* ({sup 2}P{sub 1/2}) atoms together with the CH{sub 2}Br{sup +} fragment ion. The measured rise times for Br and Br* are 130 {+-} 22 fs and 74 {+-} 10 fs, respectively. The atomic bromine quantum state distribution shows that the Br/Br* population ratio is 8.1 {+-} 3.8 and that the Br {sup 2}P{sub 3/2} state is not aligned. The observed product distribution and the timescales of the photofragment appearances suggest that multiple field-dressed potential energy surfaces are involved in the dissociative ionization process. In addition, the transient absorption spectrum of CH{sub 2}Br{sub 2}{sup +} suggests that the alignment of the molecule relative to the polarization axis of the strong-field ionizing pulse determines the electronic symmetry of the resulting ion; alignment of the Br-Br, H-H, and C{sub 2} axis of the molecule along the polarization axis results in the production of the ion {tilde X}({sup 2}B{sub 2}), {tilde B}({sup 2}B{sub 1}) and {tilde C}({sup 2}A{sub 1}) states, respectively. At higher peak intensities (6.2 x 10{sup 14} W/cm{sup 2}), CH{sub 2}Br{sub 2}{sup +} undergoes sequential ionization to form the metastable CH{sub 2}Br{sub 2}{sup 2+} dication. These results demonstrate the potential of core-level probing with high-order harmonic transient absorption spectroscopy for studying ultrafast molecular dynamics.

  10. Electrodeposition of zinc on glassy carbon from ZnCl/sub 2/ and ZnBr/sub 2/ electrolytes

    SciTech Connect (OSTI)

    McBreen, J.; Gannon, E.

    1983-08-01

    The initial stages of the electrocrystallization of zinc from 3M ZnCl/sub 2/ and 3M ZnBr/sub 2/ on glassy carbon has been investigated using cyclic voltametry, the potential step method, and scanning electron microscopy. Particular care was taken to ensure electrolyte purity and to eliminate resistance effects in the measurements. The nucleation overvoltage in 3M ZnCl/sub 2/ was about 17 and about 12 mV in 3M ZnBr/sub 2/. In 3M ZnCl/sub 2/, the current transients from the potential step measurements could be fitted to a simple model that assumes instantaneous nucleation followed by growth of three dimensional centers under kinetic control. A similar mechanism is operative for 3M ZnBr/sub 2/ at low overvoltages. At higher overvoltages, the current transient is governed by mixed kinetic and diffusion control and cannot be fitted to a simple model. The lower nucleation overvoltage and the faster kinetics in 3M ZnBr/sub 2/ is correlated with the lower stability constants for the zinc bromide complexes. Erroneous results are obtained when resistance effects are not accounted for.

  11. Towards reversible basic linear algebra subprograms: A performance study

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

    Perumalla, Kalyan S.; Yoginath, Srikanth B.

    2014-12-06

    Problems such as fault tolerance and scalable synchronization can be efficiently solved using reversibility of applications. Making applications reversible by relying on computation rather than on memory is ideal for large scale parallel computing, especially for the next generation of supercomputers in which memory is expensive in terms of latency, energy, and price. In this direction, a case study is presented here in reversing a computational core, namely, Basic Linear Algebra Subprograms, which is widely used in scientific applications. A new Reversible BLAS (RBLAS) library interface has been designed, and a prototype has been implemented with two modes: (1) amore » memory-mode in which reversibility is obtained by checkpointing to memory in forward and restoring from memory in reverse, and (2) a computational-mode in which nothing is saved in the forward, but restoration is done entirely via inverse computation in reverse. The article is focused on detailed performance benchmarking to evaluate the runtime dynamics and performance effects, comparing reversible computation with checkpointing on both traditional CPU platforms and recent GPU accelerator platforms. For BLAS Level-1 subprograms, data indicates over an order of magnitude better speed of reversible computation compared to checkpointing. For BLAS Level-2 and Level-3, a more complex tradeoff is observed between reversible computation and checkpointing, depending on computational and memory complexities of the subprograms.« less

  12. Digital reverse propagation in focusing Kerr media

    SciTech Connect (OSTI)

    Goy, Alexandre; Psaltis, Demetri

    2011-03-15

    Lenses allow the formation of clear images in homogeneous linear media. Holography is an alternative imaging method, but its use is limited to cases in which it provides an advantage, such as three-dimensional imaging. In nonlinear media, lenses no longer work. The light produces intensity-dependent aberrations. The reverse propagation method used in digital holography to form images from recorded holograms works even in Kerr media [M. Tsang, D. Psaltis, and F. G. Omenetto, Opt. Lett. 28, 1873 (2003).]. The principle has been experimentally demonstrated recently in defocusing media [C. Barsi, W.Wan, and J.W. Fleischer, Nat. Photonics 3, 211 (2009).]. Here, we report experimental results in focusing media.

  13. Review of field-reversed configurations

    SciTech Connect (OSTI)

    Steinhauer, Loren C.

    2011-07-15

    This review addresses field-reversed configurations (FRCs), which are compact-toroidal magnetic systems with little or no toroidal field and very high {beta} (ratio of plasma pressure to magnetic pressure). Although enthusiasm for the FRC has primarily been driven by its potential for an attractive fusion reactor, this review focuses on the physics rather than on technological or engineering aspects. Major advances in both theory and experiment have taken place since the previous comprehensive FRC review in 1988. Even so many questions remain. In particular, even though FRC experiments have exhibited remarkable stability, how well this extrapolates to larger systems remains unresolved. The review considers FRCs under familiar topical categories: equilibrium, global stability, self-organization, transport, formation, and sustainment.

  14. Ag/AgBr/g-C{sub 3}N{sub 4}: A highly efficient and stable composite photocatalyst for degradation of organic contaminants under visible light

    SciTech Connect (OSTI)

    Cao, Jing; Zhao, Yijie; Lin, Haili; Xu, Benyan; Chen, Shifu

    2013-10-15

    Graphical abstract: Ag/AgBr/g-C{sub 3}N{sub 4} composite photocatalysts displayed excellent photocatalytic activities on the degradation of methyl orange (MO) under visible light. The improved photocatalytic performance and stability of Ag/AgBr/g-C{sub 3}N{sub 4} originated from the synergetic effects of AgBr/g-C{sub 3}N{sub 4} interface and metallic Ag nanoparticles. O{sub 2}?, one of the reactive species, was responsible for the photodegradation of MO compared to H+ and OH. - Highlights: Novel Ag/AgBr/g-C{sub 3}N{sub 4} composite photocatalyst was reported. Ag/AgBr/g-C{sub 3}N{sub 4} had novel energy band combination between AgBr and g-C{sub 3}N{sub 4}. Synergetic effects of AgBr/g-C{sub 3}N{sub 4} interface and metallic Ag nanoparticles. Electron trapping role of metallic Ag dominated the stability of Ag/AgBr/g-C{sub 3}N{sub 4}. - Abstract: Novel Ag/AgBr/g-C{sub 3}N{sub 4} composite photocatalysts were constructed via depositionprecipitation method and extensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and UVvis diffuse reflectance spectroscopy (DRS). Under visible light (? > 420 nm), Ag/AgBr/g-C{sub 3}N{sub 4} composite photocatalysts displayed much higher photocatalytic activities than those of Ag/AgBr and g-C{sub 3}N{sub 4} for degradation of methyl orange (MO). 50% Ag/AgBr/g-C{sub 3}N{sub 4} presented the best photocatalytic performance, which was mainly attributed to the synergistic effects of AgBr/g-C{sub 3}N{sub 4} interface and the in situ metallic Ag nanoparticles for efficiently separating electronhole pairs. Furthermore, Ag/AgBr/g-C{sub 3}N{sub 4} remained good photocatalytic activity through 5 times of cycle experiments. Additionally, the radical scavengers experiment indicated that O{sub 2}{sup ?} was the main reactive species for the MO degradation under visible light.

  15. Direct molecular diffusion and micro-mixing for rapid dewatering of LiBr solution

    SciTech Connect (OSTI)

    Bigham, S; Isfahani, RN; Moghaddam, S

    2014-03-01

    A slow molecular diffusion rate often limits the desorption process of an absorbate molecule from a liquid absorbent. To enhance the desorption rate, the absorbent is often boiled to increase the liquid vapor interfacial area. However, the growth of bubbles generated during the nucleate boiling process still remains mass-diffusion limited. Here, it is shown that a desorption rate higher than that of boiling can be achieved, if the vapor absorbent interface is continuously replenished with the absorbate-rich solution to limit the concentration boundary layer growth. The study is conducted in a LiBr-water-solution, in which the water molecules' diffusion rate is quite slow. The manipulation of the vapor solution interface concentration distribution is enabled by the mechanical confinement of the solution flow within microchannels, using a hydrophobic vapor-venting membrane and the implementation of microstructures on the flow channel's bottom wall. The microstructures stretch and fold the laminar streamlines within the solution film and produce vortices. The vortices continuously replace the concentrated solution at the vapor solution interface with the water-rich solution brought from the bottom and middle of the flow channel. The physics of the process is described using a combination of experimental and numerical studies. Published by Elsevier Ltd.

  16. Photoluminescence characteristics of polariton condensation in a CuBr microcavity

    SciTech Connect (OSTI)

    Nakayama, Masaaki Murakami, Katsuya; Furukawa, Yoshiaki; Kim, DaeGwi

    2014-07-14

    We have investigated the photoluminescence (PL) properties of a CuBr microcavity at 10?K, including the temporal profiles, from the viewpoint of cavity-polariton condensation. The excitation energy density dependence of the PL intensity (band width) of the lower polariton branch at an in-plane wave vector of k{sub //}?=?0 exhibits a threshold-like increase (decrease). A large blueshift in the PL energy of ?10?meV caused by the cavity-polariton renormalization is correlated with the excitation energy density dependence of the PL intensity. The estimated density of photogenerated electron-hole pairs at the threshold is two orders lower than the Mott transition density. These results consistently demonstrate the occurrence of cavity-polariton condensation. In addition, we found that the PL rise and decay times are shortened dramatically by the cavity-polariton condensation, which reflects the bosonic final state stimulation in the relaxation process and the intrinsic cavity-polariton lifetime in the decay process.

  17. Synthesis and photocatalytic performance of an efficient Ag@AgBr/K{sub 2}Ti{sub 4}O{sub 9} composite photocatalyst under visible light

    SciTech Connect (OSTI)

    Liang, Yinghua; Lin, Shuanglong; Liu, Li; Hu, Jinshan; Cui, Wenquan

    2014-08-15

    Highlights: The plasmatic Ag@AgBr sensitized K{sub 2}Ti{sub 4}O{sub 9} composite photocatalysts. Ag@AgBr greatly increased visible light absorption for K{sub 2}Ti{sub 4}O{sub 9}. The plamonic photocatalysts exhibited enhanced activity for the degradation of RhB. - Abstract: Ag@AgBr nanoparticle-sensitized K{sub 2}Ti{sub 4}O{sub 9} composite photocatalysts (Ag@AgBr/K{sub 2}Ti{sub 4}O{sub 9}) were prepared by a facile precipitationphotoreduction method. The photocatalytic activities of the Ag@AgBr/K{sub 2}Ti{sub 4}O{sub 9} nanocomposites were evaluated for photocatalytic degradation of (RhB) under visible light irradiation. The composites exhibited excellent visible light absorption, which was attributable to the surface plasmon effect of Ag nanoparticles. The Ag@AgBr was uniformly scattered on the surface of K{sub 2}Ti{sub 4}O{sub 9} and possessed sizes in the range of 2050 nm. The loading amount of Ag@AgBr was also studied, and was found to influence the absorption spectra of the resulting composites. Approximately 95.9% of RhB was degraded by Ag@AgBr (20 wt.%)/K{sub 2}Ti{sub 4}O{sub 9} after irradiation for 1 h. The stability of the material was also investigated by performing consecutive runs. Additionally, studies performed using radical scavengers indicated that O{sub 2}{sup ?} and Br{sup 0} acted as the main reactive species. Based on the experimental results, a photocatalytic mechanism for organics degradation over Ag@AgBr/K{sub 2}Ti{sub 4}O{sub 9} photocatalysts was proposed.

  18. A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic

    Office of Scientific and Technical Information (OSTI)

    disks: distorted viscous vortex (Journal Article) | DOE PAGES DOE PAGES Search Results Accepted Manuscript: A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic disks: distorted viscous vortex « Prev Next » Title: A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic disks: distorted viscous vortex Magnetic vortices have generated intense interest in recent years due to their unique reversal mechanisms, fascinating topological properties, and exciting

  19. Membranes for Reverse-Organic Air Separations | Department of Energy

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

    Membranes for Reverse-Organic Air Separations Membranes for Reverse-Organic Air Separations New Membranes Use Reverse Separation to Reduce Pollutant Emissions Many industrial applications need a process to separate pollutants known as volatile organic compounds (VOCs) from air in order to protect the environment and save energy. One such application is the venting of vapor from underground storage tanks (UST) used in gasoline storage and dispensing. These vapors, which can build up and create

  20. Reversible Seeding in Storage Rings (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Reversible Seeding in Storage Rings Citation Details In-Document Search Title: Reversible Seeding in Storage Rings We propose to generate steady-state microbunching in a storage ring with a reversible seeding scheme. High gain harmonic generation (HGHG) and echo-enabled harmonic generation (EEHG) are two promising methods for microbunching linac electron beams. Because both schemes increase the energy spread of the seeded beam, they cannot drive a coherent radiator turn-by-turn in a storage

  1. Reversible inactivation of CO dehydrogenase with thiol compounds (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Reversible inactivation of CO dehydrogenase with thiol compounds Citation Details In-Document Search Title: Reversible inactivation of CO dehydrogenase with thiol compounds Highlights: * Rather large thiols (e.g. coenzyme A) can reach the active site of CO dehydrogenase. * CO- and H{sub 2}-oxidizing activity of CO dehydrogenase is inhibited by thiols. * Inhibition by thiols was reversed by CO or upon lowering the thiol concentration. * Thiols coordinate the Cu ion

  2. Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC...

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

    Low Degradation Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Presented at the Department of Energy Fuel Cell Projects ...

  3. Strain-assisted current-induced magnetization reversal in magnetic...

    Office of Scientific and Technical Information (OSTI)

    Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity Citation Details In-Document Search ...

  4. Materials and System Issues with Reversible SOFC | Department...

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

    Cells Workshop Summary Report Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Lessons Learned from SOFCSOEC Development...

  5. A Reversible Crystallinity-Preserving Phase Transition in Metal...

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

    Reversible Crystallinity-Preserving Phase Transition in Metal-Organic Frameworks: Discovery, Mechanistic Studies, and Potential Applications Previous Next List Liu, Dahuan; Liu,...

  6. Dynamics and efficiency of magnetic vortex circulation reversal...

    Office of Scientific and Technical Information (OSTI)

    Publisher's Accepted Manuscript: Dynamics and efficiency of magnetic vortex circulation reversal This content will become publicly available on March 15, 2016 Prev Next ...

  7. Viscosity and density of aqueous solutions of LiBr, LiCl, ZnBr[sub 2], CaCl[sub 2], and LiNO[sub 3]; 1: Single salt solutions

    SciTech Connect (OSTI)

    Wimby, J.M.; Berntsson, T.S. . Dept. of Heat and Power Technology)

    1994-01-01

    New experimental data for the viscosity and density of the binary systems lithium chloride + water, lithium bromide + water, calcium chloride + water, lithium nitrate + water, and zinc bromide + water are presented. Densities are presented in tabular form and as 10-parameter correlations, while kinematic and dynamic viscosities are presented in tabular form. Data are presented in the concentration range from intermediate dilution to close to room temperature crystallization concentration. The temperature ranges are 20--70 C for density and 25--90 C for viscosity. When available, literature data are compared with the new data, and some disagreement is found. New thermogravimetric curves are presented for the dehydration of CaCl[sub 2], ZnBr[sub 2], and LiBr in order to enable evaluation of drying as a composition determination technique.

  8. Periodicity, Electronic Structures, and Bonding of Gold Tetrahalides [AuX4](-) (X = F, CI, Br, I, At, Uus)

    SciTech Connect (OSTI)

    Li, Wan-Lu; Li, Yong; Xu, Congqiao; Wang, Xue B.; Vorpagel, Erich R.; Li, Jun

    2015-12-07

    Systematic theoretical and experimental investigations have been performed to understand the periodicity and electronic structures of trivalent-gold halides using gold tetrahalides [AuX4]⁻ anions (X = F, Cl, Br, I, At, Uus). The [AuX4]⁻ (X = Cl, Br, I) anions were produced in gas phase and their negative-ion photoelectron spectra were obtained, which exhibited rich and well-resolved spectral peaks. We calculated the adiabatic as well as vertical electron detachment energies using density functional methods with scalar and spin-orbit coupling relativistic effects. The simulated photoelectron spectra based on these calculations are in good agreement with the experimental spectra. Our results show that the trivalent Au(III) oxidation state becomes progressively less stable while Au(I) is preferred when the halides become heavier along the Period Table. This trend reveals that the oxidation state of metals in complexes can be manipulated through ligand design

  9. Comparison of CsBr and KBr coated Cu photocathodes: Effects of laser irradiation and work function changes

    SciTech Connect (OSTI)

    He, Weidong; VilayurGanapathy, Subramanian; Joly, Alan G.; Droubay, Timothy C.; Chambers, Scott A.; Maldonado, Juan R.; Hess, Wayne P.

    2013-02-20

    Thin films (7 nm layers) of CsBr and KBr were deposited on Cu(100) to investigate photoemission properties of these potential photocathode materials. After thin film deposition and prolonged laser ultraviolet (UV) irradiation (266 nm picosecond laser) photoemission quantum efficiency increases by factors of 26 and 77 for KBr/Cu(100) and CsBr/Cu(100) photocathodes, respectively. Immediately following thin film deposition, a decrease in work function is observed, compared to bare Cu, in both cases. Quantum efficiency enhancements are attributed to the decrease in photocathode work function, due to the deposition of alkali halide thin films, and photo-induced processes, that introduce defect states into the alkali halide bandgap, induced by UV laser irradiation. It is possible that alkali metal formation occurs during UV irradiation and that this further contributes to photoemission enhancement. Our results suggest that KBr, a relatively stable alkali-halide, has potential for photocathode applications.

  10. Reversible piezomagnetoelectric switching in bulk polycrystalline ceramics

    SciTech Connect (OSTI)

    Stevenson, T. Bennett, J.; Brown, A. P.; Wines, T.; Bell, A. J.; Comyn, T. P.; Smith, R. I.

    2014-08-01

    Magnetoelectric (ME) coupling in materials offer tremendous advantages in device functionality enabling technologies including advanced electronic memory, combining electronic speed, and efficiency with magnetic robustness. However, low cost polycrystalline ME materials are excluded from most commercial applications, operating only at cryogenic temperatures, impractically large electric/magnetic fields, or with low ME coefficients (1-100 mV/cm Oe). Despite this, the technological potential of single compound ME coupling has continued to drive research into multiferroics over the last two decades. Here we show that by manipulating the large induced atomic strain within the polycrystalline, room temperature multiferroic compound 0.7BiFeO{sub 3}–0.3PbTiO{sub 3}, we can induce a reversible, piezoelectric strain controlled ME effect. Employing an in situ neutron diffraction experiment, we have demonstrated that this piezomagnetoelectric effect manifests with an applied electric field >8 kV/mm at the onset of piezoelectric strain, engineered in to the compound by crystallographic phase mixing. This produces a remarkable intrinsic ME coefficient of 1276 mV/cm Oe, due to a strain driven modification to the oxygen sub-lattice, inducing an increase in magnetic moment per Fe{sup 3+} ion of +0.142 μ{sub B}. This work provides a framework for investigations into strain engineered nanostructures to realize low-cost ME devices designed from the atoms up, as well as contributing to the deeper understanding of single phase ME coupling mechanisms.

  11. Liquid suspensions of reversible metal hydrides

    DOE Patents [OSTI]

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

    1983-12-08

    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.

  12. A high performance field-reversed configuration

    SciTech Connect (OSTI)

    Binderbauer, M. W.; Tajima, T.; Steinhauer, L. C.; Garate, E.; Tuszewski, M.; Smirnov, A.; Gota, H.; Barnes, D.; Deng, B. H.; Thompson, M. C.; Trask, E.; Yang, X.; Putvinski, S.; Rostoker, N.; Andow, R.; Aefsky, S.; Bolte, N.; Bui, D. Q.; Ceccherini, F.; Clary, R.; and others

    2015-05-15

    Conventional field-reversed configurations (FRCs), high-beta, prolate compact toroids embedded in poloidal magnetic fields, face notable stability and confinement concerns. These can be ameliorated by various control techniques, such as introducing a significant fast ion population. Indeed, adding neutral beam injection into the FRC over the past half-decade has contributed to striking improvements in confinement and stability. Further, the addition of electrically biased plasma guns at the ends, magnetic end plugs, and advanced surface conditioning led to dramatic reductions in turbulence-driven losses and greatly improved stability. Together, these enabled the build-up of a well-confined and dominant fast-ion population. Under such conditions, highly reproducible, macroscopically stable hot FRCs (with total plasma temperature of ∼1 keV) with record lifetimes were achieved. These accomplishments point to the prospect of advanced, beam-driven FRCs as an intriguing path toward fusion reactors. This paper reviews key results and presents context for further interpretation.

  13. Rigid-rotor, field-reversed configuration

    SciTech Connect (OSTI)

    Conti, F. Giammanco, F.; Plasma Diagnostics and Technologies Ltd., Via Giuntini 63, 56023 Navacchio ; Wessel, F. J.; Binderbauer, M. W.; Bolte, N.; Morehouse, M.; Qerushi, A.; Rahman, H. U.; Roche, T.; Slepchenkov, M.

    2014-02-15

    The radial profiles, n(r), B{sub z}(r), and E{sub r}(r), for a Flux-Coil (“inductively driven”), Field-Reversed Configuration (FC-FRC) are measured and compared to the predictions of the Rigid-Rotor Model (RRM), which is an analytic, one-dimensional, time-independent, equilibrium description for the FRC. Injectors mounted on both ends of the confinement vessel provide a pre-fill plasma. Coaxial coils mounted outside the vacuum boundaries of the annular-confinement vessel accelerate the plasma and produce the FRC. The density profile is measured by laser interferometry, the magnetic-field profile using an in-situ probe array, and the electric-field profile using an in-situ, floating-probe array. Free parameters for each profile are measured, which also allow other intrinsic-plasma parameters to be determined, using computer-fit algorithms: null radius, radial thickness, plasma temperature, rotation frequencies, the latter of which are independently verified by spectroscopy. All radial profiles agree with the RRM predictions, for the experimental configuration, parameter regime, and specified-time interval studied here.

  14. Cs{sub 3}Zr{sub 6}Br{sub 15}Z (Z = C, B): A stuffed rhombohedral perovskite structure of linked clusters

    SciTech Connect (OSTI)

    Qi, Ru-Yi; Corbett, J.D.

    1995-03-29

    The isostructural title compounds are synthesized in good yields form reactions of Zr, ZrBr{sub 4}, CsBr, and Z in sealed Ta tubing for {approximately}3 weeks at 850 {degrees}C. Their single-crystal data refinements established the products as Cs{sub 3.02(7)-}Zr{sub 6}Br{sub 14}C and Cs{sub 3.39(5)}Zr{sub 6}br{sub 15}B (R3c, Z = 6, a = 13.1031 (6), 13.116(1) {angstrom}, c = 35.800(3), 35.980(6) {angstrom}, R(F)/R{sub w} = 5.4/5.9, 5.4/4.4%, respectively). The structure is derived form a three-dimensional [Zr{sub 6}(Z)Br{sub 12}]Br{sub 6/2} network of four-rings (as in ReO{sub 6/2}) twisted into a rhombohedral perovskite analogous to VF{sub 3}. The three necessary Cs{sup +} cations are fractionally distributed over five sites that are far from optimal or common, with either eight asymmetric or only three close bromide neighbors. Refinement of a third Cs{sub 3.18(5)}Zr{sub 6}Br{sub 15}C structure at {minus}50 {degrees}C gave the same result with somewhat smaller positional distributions of the atoms.

  15. Palladium-catalyzed Br/D exchange of arenes: Selective deuterium incorporation with versatile functional group tolerance and high efficiency

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

    Zhang, Honghai -Hai; Bonnesen, Peter V.; Hong, Kunlun

    2015-07-13

    There is a facile method for introducing one or more deuterium atoms onto an aromatic nucleus via Br/D exchange with high functional group tolerance and high incorporation efficiency is disclosed. Deuterium-labeled aryl chlorides and aryl borates which could be used as substrates in cross-coupling reactions to construct more complicated deuterium-labeled compounds can also be synthesized by this method.

  16. Magnetic excitations in the spin-1/2 triangular-lattice antiferromagnet Cs2CuBr4

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

    Zvyagin, S. A.; Ozerov, M.; Kamenskyi, D.; Wosnitza, J.; Krzystek, J.; Yoshizawa, D.; Hagiwara, M.; Hu, Rongwei; Ryu, Hyejin; Petrovic, C.; et al

    2015-11-27

    We present on high- field electron spin resonance (ESR) studies of magnetic excitations in the spin- 1/2 triangular-lattice antiferromagnet Cs2CuBr4. Frequency- field diagrams of ESR excitations are measured for different orientations of magnetic fields up to 25 T. We show that the substantial zero- field energy gap, Δ ≈ 9.5 K, observed in the low-temperature excitation spectrum of Cs2CuBr4 [Zvyagin et al:, Phys. Rev. Lett. 112, 077206 (2014)], is present well above TN. Noticeably, the transition into the long-range magnetically ordered phase does not significantly affect the size of the gap, suggesting that even below TN the high-energy spin dynamicsmore » in Cs2CuBr4 is determined by short-range-order spin correlations. The experimental data are compared with results of model spin-wave-theory calculations for spin-1/2 triangle-lattice antiferromagnet.« less

  17. Reversibly immobilized biological materials in monolayer films on electrodes

    DOE Patents [OSTI]

    Weaver, Paul F. (Golden, CO); Frank, Arthur J. (Lakewood, CO)

    1993-01-01

    Methods and techniques are described for reversibly binding charged biological particles in a fluid medium to an electrode surface. The methods are useful in a variety of applications. The biological materials may include microbes, proteins, and viruses. The electrode surface may consist of reversibly electroactive materials such as polyvinylferrocene, silicon-linked ferrocene or quinone.

  18. Reversibly immobilized biological materials in monolayer films on electrodes

    DOE Patents [OSTI]

    Weaver, P.F.; Frank, A.J.

    1993-05-04

    Methods and techniques are described for reversibly binding charged biological particles in a fluid medium to an electrode surface. The methods are useful in a variety of applications. The biological materials may include microbes, proteins, and viruses. The electrode surface may consist of reversibly electroactive materials such as polyvinylferrocene, silicon-linked ferrocene or quinone.

  19. Method for distinguishing multiple targets using time-reversal acoustics

    DOE Patents [OSTI]

    Berryman, James G.

    2004-06-29

    A method for distinguishing multiple targets using time-reversal acoustics. Time-reversal acoustics uses an iterative process to determine the optimum signal for locating a strongly reflecting target in a cluttered environment. An acoustic array sends a signal into a medium, and then receives the returned/reflected signal. This returned/reflected signal is then time-reversed and sent back into the medium again, and again, until the signal being sent and received is no longer changing. At that point, the array has isolated the largest eigenvalue/eigenvector combination and has effectively determined the location of a single target in the medium (the one that is most strongly reflecting). After the largest eigenvalue/eigenvector combination has been determined, to determine the location of other targets, instead of sending back the same signals, the method sends back these time reversed signals, but half of them will also be reversed in sign. There are various possibilities for choosing which half to do sign reversal. The most obvious choice is to reverse every other one in a linear array, or as in a checkerboard pattern in 2D. Then, a new send/receive, send-time reversed/receive iteration can proceed. Often, the first iteration in this sequence will be close to the desired signal from a second target. In some cases, orthogonalization procedures must be implemented to assure the returned signals are in fact orthogonal to the first eigenvector found.

  20. Reducing current reversal time in electric motor control

    DOE Patents [OSTI]

    Bredemann, Michael V

    2014-11-04

    The time required to reverse current flow in an electric motor is reduced by exploiting inductive current that persists in the motor when power is temporarily removed. Energy associated with this inductive current is used to initiate reverse current flow in the motor.

  1. Magnetization reversal in TmCrO{sub 3}

    SciTech Connect (OSTI)

    Yoshii, Kenji

    2012-11-15

    Highlights: ► We observed two magnetization reversals in TmCrO{sub 3}. ► The reversal at 28 K is attributed to antiparallel coupling between Cr{sup 3+} and Tm{sup 3+}. ► The other reversal originates from spin reorientation. ► Magnetocaloric effect is observed at the spin reorientation temperature. ► Characteristic magnetization switching is demonstrated. -- Abstract: The perovskite chromite TmCrO{sub 3} shows magnetization reversal at two temperatures. The reversal at ∼28 K is attributed to the antiparallel coupling between Tm{sup 3+} and Cr{sup 3+} moments, while that at the lower temperature (∼6–7 K) is rooted in a rotation of the magnetic moments. Magnetocaloric measurements offer a relatively large entropy change (∼4–5 J kg{sup −1} K{sup −1}) at the lower temperature. The reversal at ∼28 K is accompanied by a sign change of an exchange-bias-like field. The absence of the training effect suggests that this behavior is rooted in unidirectional magnetic anisotropy. The existence of the two magnetization reversals offers the characteristic switching of magnetization. For example, the magnetization is flipped without changing the direction of the applied magnetic field.

  2. Preparation, characterization and photocatalytic activity of visible-light-driven plasmonic Ag/AgBr/ZnFe{sub 2}O{sub 4} nanocomposites

    SciTech Connect (OSTI)

    Li, Xiaojuan Tang, Duanlian; Tang, Fan; Zhu, Yunyan; He, Changfa; Liu, Minghua Lin, Chunxiang; Liu, Yifan

    2014-08-15

    Highlights: A plasmonic Ag/AgBr/ZnFe{sub 2}O{sub 4} photocatalyst has been successfully synthesized. Ag/AgBr/ZnFe{sub 2}O{sub 4} nanocomposites exhibit high visible light photocatalytic activity. Ag/AgBr/ZnFe{sub 2}O{sub 4} photocatalyst is stable and magnetically separable. - Abstract: A visible-light-driven plasmonic Ag/AgBr/ZnFe{sub 2}O{sub 4} nanocomposite has been successfully synthesized via a depositionprecipitation and photoreduction through a novel one-pot process. X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and UVvis diffuse reflectance spectroscopy were employed to investigate the crystal structure, chemical composition, morphology, and optical properties of the as-prepared nanocomposites. The photocatalytic activities of the nanocomposites were evaluated by photodegradation of Rhodamine B (RhB) and phenol under visible light. The results demonstrated that the obtained Ag/AgBr/ZnFe{sub 2}O{sub 4} nanocomposites exhibited higher photocatalytic activity as compared to pure ZnFe{sub 2}O{sub 4}. In addition, the sample photoreduced for 20 min and calcined at 500 C achieved the highest photocatalytic activity. Furthermore, the Ag/AgBr/ZnFe{sub 2}O{sub 4} nanocomposite has high stability under visible light irradiation and could be conveniently separated by using an external magnetic field.

  3. Nanostructured Lanthanum Halides and CeBr3 for Nuclear Radiation and Detection

    SciTech Connect (OSTI)

    Paul Guss, Sanjoy Mukhopadhyay, Ron Guise, Ding Yuan

    2010-06-09

    Scintillator materials are used to detect, and in some cases identify, gamma rays. Higher performance scintillators are expensive, hard to manufacture, fragile, and sometimes require liquid nitrogen or cooling engines. But whereas lower-quality scintillators are cheap, easy to manufacture, and more rugged, their performance is lower. At issue: can the desirable qualities of high-and low-performance scintillators be combined to achieve better performance at lower cost? Preliminary experiments show that a LaF{sub 3}:Ce oleic acid-based nanocomposite exhibits a photopeak when exposed to {sup 137}Cs source gamma-radiation. The chemical synthesis of the cerium-doped lanthanum halide nanoparticles are scalable and large quantities of material can be produced at a time, unlike typical crystal growth processes such as the Bridgeman process. Using a polymer composite (Figure 1), produced by LANL, initial measurements of the unloaded and 8% LaF{sub 3}:Ce-loaded sample have been made using {sup 137}Cs sources. Figure 2 shows an energy spectrum acquired for CeF{sub 3}. The lighter plot is the measured polymer-only spectrum and the black plot is the spectrum from the nanocomposite scintillator. As the development of this material continues, the energy resolution is expected to improve and the photopeak-to-Compton ratio will become greater at higher loadings. These measurements show the expected Compton edge in the polymer-only sample, and the Compton edge and photo-peak expected in the nanophosphor composites that LANL has produced. Using a porous VYCORR with CdSe/ZnS core shell quantum dots, Letant has demonstrated that he has obtained signatures of the 241Am photopeak with energy resolution as good at NaI (Figure 3). We begin with the fact that CeBr{sub 3} crystals do not have a self-activity component as strong as the lanthanum halides. The radioactive 0.090% {sup 138}La component of lanthanum leads to significant self-activity, which will be a problem for very large detector volumes. Yet a significant strength of the nanostructure detector concept is the ability to create extremely large detector volumes by mixing nanoparticles into a transparent matrix. This would argue for use of nanoparticles other than lanthanum halides. Nanocomposites are easy to prepare; it is much less costly to use nanocomposites than to grow large whole crystals of these materials. The material can be fabricated at an industrial scale, further reducing cost. This material potentially offers the performance of $300/cc material (e.g., lanthanum bromide) at a cost of $1/cc. Because the material acts as a plastic, it is rugged and flexible, and can be made in large sheets, increasing the sensitivity of a detector using it. It would operate at ambient temperatures. Very large volumes of detector may be produced at greatly reduced cost, enhancing the non-proliferation posture of the nation for the same dollar value.

  4. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    millitesla (mT) to reverse the direction of a vortex core. ... and their possible application to data storage technologies. ... Is there a physical limit to how far this process can go? At ...

  5. Time-reversal-invariant topological superconductivity in n -doped...

    Office of Scientific and Technical Information (OSTI)

    This content will become publicly available on April 22, 2016 Title: Time-reversal-invaria... become publicly available on April 22, 2016 Publisher's Version of Record 10.1103...

  6. Reversibility and criticality in amorphous solids (Journal Article) |

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Reversibility and criticality in amorphous solids Citation Details In-Document Search Title: Reversibility and criticality in amorphous solids The physical processes governing the onset of yield, where a material changes its shape permanently under external deformation, are not yet understood for amorphous solids that are intrinsically disordered. Here, using molecular dynamics simulations and mean-field theory, we show that at a critical strain amplitude the sizes of

  7. Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak

    Office of Scientific and Technical Information (OSTI)

    Ohmic L -Mode Plasmas (Journal Article) | SciTech Connect Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L -Mode Plasmas Citation Details In-Document Search Title: Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L -Mode Plasmas Authors: Rice, J. E. ; Cziegler, I. ; Diamond, P. H. ; Duval, B. P. ; Podpaly, Y. A. ; Reinke, M. L. ; Ennever, P. C. ; Greenwald, M. J. ; Hughes, J. W. ; Ma, Y. ; Marmar, E. S. ; Porkolab, M. ;

  8. Modified polynomial function model for reversed-field pinches

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

    Modified polynomial function model for reversed-field pinches W. Shen and J. C. Sprott Department of Physics, University of Wisconsin, Madison, Wisconsin 53 706 (Received 26 November 1990; accepted 29 January 199 1) A generalized analytic representation for the magnetic field and current density profiles in a reversed-field pinch (RFP) is proposed. These profiles have zero current density at the wall and finite plasma pressure. The profiles are characterized by two free parameters here taken to

  9. Preliminary design report: Babcock and Wilcox BR-100 100-ton rail/barge spent fuel shipping cask

    SciTech Connect (OSTI)

    None

    1990-02-01

    The purpose of this document is to provide information on burnup credit as applied to the preliminary design of the BR-100 shipping cask. There is a brief description of the preliminary basket design and the features used to maintain a critically safe system. Following the basket description is a discussion of various criticality analyses used to evaluate burnup credit. The results from these analyses are then reviewed in the perspective of fuel burnups expected to be shipped to either the final repository or a Monitored Retrievable Storage (MRS) facility. The hurdles to employing burnup credit in the certification of any cask are then outlines and reviewed. the last section gives conclusions reached as to burnup credit for the BR-100 cask, based on our analyses and experience. All information in this study refers to the cask configured to transport PWR fuel. Boiling Water Reactor (BWR) fuel satisfies the criticality requirements so that burnup credit is not needed. All calculations generated in the preparation of this report were based upon the preliminary design which will be optimized during the final design. 8 refs., 19 figs., 16 tabs.

  10. Dissociative adsorption of CH{sub 3}X (X = Br and Cl) on a silicon(100) surface revisited by density functional theory

    SciTech Connect (OSTI)

    Wang, Chen-Guang; Huang, Kai E-mail: wji@ruc.edu.cn; Ji, Wei E-mail: wji@ruc.edu.cn

    2014-11-07

    During the dissociative adsorption on a solid surface, the substrate usually participates in a passive manner to accommodate fragments produced upon the cleavage of the internal bond(s) of a (transient) molecular adsorbate. This simple picture, however, neglects the flexibility of surface atoms. Here, we report a Density Functional Theory study to revisit our early studies of the dissociative adsorption of CH{sub 3}X (X = Br and Cl) on Si(100). We have identified a new reaction pathway, which involves a flip of a silicon dimer; this new pathway agrees better with experiments. For our main exemplar of CH{sub 3}Br, insights have been gained using a simple model that involves a three-atom reactive center, Br-C-Si. When the silicon dimer flips, the interaction between C and Si in the Br-C-Si center is enhanced, evident in the increased energy-split of the frontier orbitals. We also examine how the dissociation dynamics of CH{sub 3}Br is altered on a heterodimer (Si-Al, Si-P, and Si-Ge) in a Si(100) surface. In each case, we conclude, on the basis of computed reaction pathways, that no heterodimer flipping is involved before the system transverses the transition state to dissociative adsorption.

  11. Implications of Scheduled ITC Reversion for RPS Compliance: Preliminary Results

    SciTech Connect (OSTI)

    Lowder, Travis; Miller, John; O'Shaughnessy, Eric; Heeter, Jenny

    2015-09-14

    This poster presents DRAFT initial results of a forthcoming NREL analysis. The analysis investigates the impacts of the scheduled investment tax credit (ITC) reversion from 30 percent to 10 percent for certain solar photovoltaic projects. Specifically, it considers whether the reversion will result in increased use of alternative compliance payments (ACPs) in lieu of solar renewable energy credits (SRECs) for renewable portfolio standard (RPS) compliance. The analysis models the effect of a 10 percent ITC on power purchase agreement (PPA) prices for non-residential systems in the eight states with solar carve-outs and solar ACPs. Our preliminary results suggest that states will likely install sufficient capacity to meet long-term targets through SRECs rather than ACPs following the ITC reversion. However, the analysis shows that the ITC reversion could affect project economics such that capacity shortfalls in certain states could temporarily increase the use of ACPs. NREL anticipates publishing a full report of this analysis in fall 2015. credits (SRECs) for renewable portfolio standard (RPS) compliance. The analysis models the effect of a 10 percent ITC on power purchase agreement (PPA) prices for non-residential systems in the eight states with solar carve-outs and solar ACPs. Our preliminary results suggest that states will likely install sufficient capacity to meet long-term targets through SRECs rather than ACPs following the ITC reversion. However, the analysis shows that the ITC reversion could affect project economics such that capacity shortfalls in certain states could temporarily increase the use of ACPs. NREL anticipates publishing a full report of this analysis in fall 2015.

  12. E-print Network : Main View : Search Results for Title: "Reversible...

    Office of Scientific and Technical Information (OSTI)

    Reversible control of spin-polarized supercurrents in ferromagnetic Josephson junctions" Author: Banerjee AND Robinson...

  13. Reversible Alteration of CO2 Adsorption upon Photochemical or Thermal

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

    Treatment in a Metal-Organic Framework | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Reversible Alteration of CO2 Adsorption upon Photochemical or Thermal Treatment in a Metal-Organic Framework Previous Next List Jinhee Park , Daqiang Yuan , Khanh T. Pham , Jian-Rong Li , Andrey Yakovenko , and Hong-Cai Zhou, J. Am. Chem. Soc., 2012, 134 (1), pp 99-102 DOI: 10.1021/ja209197f Abstract Image Abstract: A metal-organic framework (MOF) for reversible

  14. Reverse phase transformation of martensite to austenite in stainless

    Office of Scientific and Technical Information (OSTI)

    steels: a 3D phase-field study (Journal Article) | SciTech Connect Reverse phase transformation of martensite to austenite in stainless steels: a 3D phase-field study Citation Details In-Document Search Title: Reverse phase transformation of martensite to austenite in stainless steels: a 3D phase-field study Authors: Yeddu, Hemantha K. [1] ; Lookman, Turab [1] ; Saxena, Avadh B. [1] + Show Author Affiliations Los Alamos National Laboratory Publication Date: 2014-08-19 OSTI Identifier:

  15. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Magnetic Vortex Core Reversal by Low-Field Excitations Print Wednesday, 28 March 2007 00:00 In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to

  16. Energy current imaging method for time reversal in elastic media

    SciTech Connect (OSTI)

    Anderson, Brian E; Ulrich, Timothy J; Le Bas, Pierre - Yves A; Larmat, Carene; Johnson, Paul A; Guyer, Robert A; Griffa, Michele

    2009-01-01

    An energy current imaging method is presented for use in locating sources of wave energy during the back propagation stage of the time reversal process. During the back propagation phase of an ideal time reversal experiment, wave energy coalesces from all angles of incidence to recreate the source event; after the recreation, wave energy diverges in every direction. An energy current imaging method based on this convergence/divergence behavior has been developed. The energy current imaging method yields a smaller spatial distribution for source reconstruction than is possible with traditional energy imaging methods.

  17. Environmental effects on noble-gas hydrides: HXeBr, HXeCCH, and HXeH in noble-gas and molecular matrices

    SciTech Connect (OSTI)

    Tsuge, Masashi E-mail: leonid.khriachtchev@helsinki.fi; Lignell, Antti; Rsnen, Markku; Khriachtchev, Leonid E-mail: leonid.khriachtchev@helsinki.fi

    2013-11-28

    Noble-gas hydrides HNgY (Ng is a noble-gas atom and Y is an electronegative group) are sensitive probes of local environment due to their relatively weak bonding and large dipole moments. We experimentally studied HXeBr in Ar, Kr, and N{sub 2} matrices, HXeCCH in Ne and N{sub 2} matrices, and HXeH in an N{sub 2} matrix. These are the first observations of noble-gas hydrides in an N{sub 2} matrix. An N{sub 2} matrix strongly increases the HXe stretching frequency of HXeBr and HXeCCH with respect to a Ne matrix, which is presumably due to a strong interaction between the HNgY dipole moment and quadrupole moments of the surrounding lattice N{sub 2} molecules. The spectral shift of HXeBr in an N{sub 2} matrix is similar to that in a CO{sub 2} matrix, which is a rather unexpected result because the quadrupole moment of CO{sub 2} is about three times as large as that of N{sub 2}. The HXe stretching frequencies of HXeBr and HXeCCH in noble-gas matrices show a trend of ?(Ne) < ?(Xe) < ?(Kr) < ?(Ar), which is a non-monotonous function of the dielectric constants of the noble-gas solids. The MP2(full) calculations of HXeBr and HXeCCH with the polarizable continuum model as well as the CCSD(T) calculations of the HXeBrNg and HXeCCHNg (Ng = Ne, Ar, Kr, and Xe) complexes cannot fully explain the experimental observations. It is concluded that more sophisticated computational models should be used to describe these experimental findings.

  18. Stabilized wide bandgap MAPbBrxI3-x perovskite by enhanced grain size and improved crystallinity

    SciTech Connect (OSTI)

    Hu, Miao; Bi, Cheng; Yuan, Yongbo; Bai, Yang; Huang, Jinsong

    2015-12-07

    In this study, the light instability of CH3NH3PbIxBr3x has been raised one of the biggest challenges for its application in tandem solar cells. Here we show that an improved crystallinity and grain size of CH3NH3PbIxBr3x films could stabilize these materials under one sun illumination, improving both the efficiency and stability of the wide-bandgap perovskite solar cells.

  19. Reversing-counterpulse repetitive-pulse inductive storage circuit

    DOE Patents [OSTI]

    Honig, Emanuel M.

    1987-01-01

    A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.

  20. Reversing-counterpulse repetitive-pulse inductive storage circuit

    DOE Patents [OSTI]

    Honig, E.M.

    1984-06-05

    A high power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.

  1. Rotational stability of a long field-reversed configuration

    SciTech Connect (OSTI)

    Barnes, D. C. Steinhauer, L. C.

    2014-02-15

    Rotationally driven modes of long systems with dominantly axial magnetic field are considered. We apply the incompressible model and order axial wavenumber small. A recently developed gyro-viscous model is incorporated. A one-dimensional equilibrium is assumed, but radial profiles are arbitrary. The dominant toroidal (azimuthal) mode numbers ℓ=1 and ℓ=2 modes are examined for a variety of non-reversed (B) and reversed profiles. Previous results for both systems with rigid rotor equilibria are reproduced. New results are obtained by incorporation of finite axial wavenumber and by relaxing the assumption of rigid electron and ion rotation. It is shown that the frequently troublesome ℓ=2 field reversed configuration (FRC) mode is not strongly affected by ion kinetic effects (in contrast to non-reversed cases) and is likely stabilized experimentally only by finite length effects. It is also shown that the ℓ=1 wobble mode has a complicated behavior and is affected by a variety of configuration and profile effects. The rotationally driven ℓ=1 wobble is completely stabilized by strong rotational shear, which is anticipated to be active in high performance FRC experiments. Thus, observed wobble modes in these systems are likely not driven by rotation alone.

  2. Reversing-counterpulse repetitive-pulse inductive storage circuit

    DOE Patents [OSTI]

    Honig, E.M.

    1987-02-10

    A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime. 10 figs.

  3. Simulation studies of nucleation of ferroelectric polarization reversal.

    SciTech Connect (OSTI)

    Brennecka, Geoffrey L.; Winchester, Benjamin Michael

    2014-08-01

    Electric field-induced reversal of spontaneous polarization is the defining characteristic of a ferroelectric material, but the process(es) and mechanism(s) associated with the initial nucleation of reverse-polarity domains are poorly understood. This report describes studies carried out using phase field modeling of LiTaO3, a relatively simple prototype ferroelectric material, in order to explore the effects of either mechanical deformation or optically-induced free charges on nucleation and resulting domain configuration during field-induced polarization reversal. Conditions were selected to approximate as closely as feasible those of accompanying experimental work in order to provide not only support for the experimental work but also ensure that additional experimental validation of the simulations could be carried out in the future. Phase field simulations strongly support surface mechanical damage/deformation as effective for dramatically reducing the overall coercive field (Ec) via local field enhancements. Further, optically-nucleated polarization reversal appears to occur via stabilization of latent nuclei via the charge screening effects of free charges.

  4. CROSSED MOLECULAR BEAM STUDIES OF CHEMILUMINESCENT REACTIONS: F{sub 2} + I{sub 2}, Br{sub 2} and ICl

    SciTech Connect (OSTI)

    Kahler, C.C.; Lee, Y.T.

    1980-05-01

    The chemiluminescent bimolecular halogen-halogen reactions, F{sub 2} + I{sub 2}, Br{sub 2} and ICl, have been studied by the crossed molecular beam technique. Undispersed chemiluminescence was measured as a function of collision energy and, for I{sub 2} + F{sub 2}, as a function of the two beam pressures. Although no spectra were obtained to positively identify the emitters as IF*, ClF* and BrF*, arguments are given to support this identification. The observed reaction thresholds of 4.2 and 5.9 kcal/mole for I{sub 2} + F{sub 2} and ICl + F{sub 2} , respectively, are the same as the threshold energies for production of the stable trihalogens I{sub 2}F and ClF. This coincidence of threshold energies, as well as similar high collision energy behavior, implies that the chemiluminescent reaction proceeds via a stable trihalogen intermediate. This mechanism can explain our results and the results of other workers without resorting to a symmetry forbidden four center reaction mechanism. A threshold of 11.3 kcal/mole was found for Br{sub 2} + F{sub 2} , no threshold for Br{sub 2}F has been previously reported. Laser enhancement of the I{sub 2} + F{sub 2} reaction was attempted, but no enhancement was seen.

  5. ITP Industrial Distributed Energy: A Guide to Developing Air-Cooled LiBr Absorption for Combined Heat and Power Applications

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

    Guide to Developing Air- Cooled LiBr Absorption for Combined Heat and Power Applications April 2005 By Robert A. Zogg Michael Y. Feng Detlef Westphalen TIAX LLC Re: D0281 Table of Contents 1.0 INTRODUCTION/BACKGROUND .................................................................................................1 2.0 LIBR ABSORPTION OVERVIEW...................................................................................................3 3.0 KEY TECHNOLOGY BARRIERS

  6. Fast chirality reversal of the magnetic vortex by electric current

    SciTech Connect (OSTI)

    Lim, W. L. Liu, R. H.; Urazhdin, S.; Tyliszczak, T.; Erokhin, S. G.; Berkov, D.

    2014-12-01

    The possibility of high-density information encoding in magnetic materials by topologically stable inhomogeneous magnetization configurations such as domain walls, skyrmions, and vortices has motivated intense research into mechanisms enabling their control and detection. While the uniform magnetization states can be efficiently controlled by electric current using magnetic multilayer structures, this approach has proven much more difficult to implement for inhomogeneous states. Here, we report direct observation of fast reversal of magnetic vortex by electric current in a simple planar structure based on a bilayer of spin Hall material Pt with a single microscopic ferromagnetic disk contacted by asymmetric electrodes. The reversal is enabled by a combination of the chiral Oersted field and spin current generated by the nonuniform current distribution in Pt. Our results provide a route for the efficient control of inhomogeneous magnetization configurations by electric current.

  7. Forward and reverse control system for induction motors

    DOE Patents [OSTI]

    Wright, J.T.

    1987-09-15

    A control system for controlling the direction of rotation of a rotor of an induction motor includes an array of five triacs with one of the triacs applying a current of fixed phase to the windings of the rotor and four of the triacs being switchable to apply either hot ac current or return ac current to the stator windings so as to reverse the phase of current in the stator relative to that of the rotor and thereby reverse the direction of rotation of the rotor. Switching current phase in the stator is accomplished by operating the gates of pairs of the triacs so as to connect either hot ac current or return ac current to the input winding of the stator. 1 fig.

  8. Reversible geling co-polymer and method of making

    DOE Patents [OSTI]

    Gutowska, Anna

    2005-12-27

    The present invention is a thereapeutic agent carrier having a thermally reversible gel or geling copolymer that is a linear random copolymer of an [meth-]acrylamide derivative and a hydrophilic comonomer, wherein the linear random copolymer is in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum geling molecular weight cutoff and a therapeutic agent.

  9. Cooling by Time Reversal of Atomic Matter Waves

    SciTech Connect (OSTI)

    Martin, J.; Georgeot, B.; Shepelyansky, D. L. [Laboratoire de Physique Theorique, Universite de Toulouse III, CNRS, 31062 Toulouse (France)

    2008-02-01

    We propose an experimental scheme which allows us to realized approximate time reversal of matter waves for ultracold atoms in the regime of quantum chaos. We show that a significant fraction of the atoms return back to their original state, being at the same time cooled down by several orders of magnitude. We give a theoretical description of this effect supported by extensive numerical simulations. The proposed scheme can be implemented with existing experimental setups.

  10. Corrosion/erosion pipe inspection using reverse geometry radiography

    SciTech Connect (OSTI)

    Albert, R.D.

    1996-07-01

    Measurement of corrosion in piping was studied using the Digiray Reverse Geometry X-ray{reg_sign} (RGX{reg_sign}) imaging system during a series of field tests. Sponsored by Shell, Exxon and Mobil oil companies, these were recently carried out at the Shell Martinez refinery facility. Results of the field tests as well as other RGX radiographs taken in the laboratory by Digiray will be described in this report.

  11. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  12. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  13. Photochromic Metal-Organic Frameworks: Reversible Control of Singlet

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

    Oxygen Generation | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Photochromic Metal-Organic Frameworks: Reversible Control of Singlet Oxygen Generation Previous Next List Jihye Park, Dawei Feng, Shuai Yuan and Hong-Cai Zhou, Angew. Chem. Int. Ed. 54, 430-435 (2014) DOI: 10.1002/anie.201408862 Abstract: The controlled generation of singlet oxygen is of great interest owing to its potential applications including industrial wastewater treatment,

  14. Reversible Switching from Antiferro- to Ferromagnetic Behavior by

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

    Solvent-Mediated, Thermally-Induced Phase Transitions in a Trimorphic MOF-Based Magnetic Sponge System | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Reversible Switching from Antiferro- to Ferromagnetic Behavior by Solvent-Mediated, Thermally-Induced Phase Transitions in a Trimorphic MOF-Based Magnetic Sponge System Previous Next List Mario Wriedt, Andrey A. Yakovenko, Gregory J. Halder, Andrey V. Prosvirin, Kim R. Dunbar, and Hong-Cai Zhou, J. Am. Chem.

  15. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  16. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  17. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  18. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  19. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  20. Dynamic processes in field-reversed-configuration compact toroids

    SciTech Connect (OSTI)

    Rej, D.J.

    1987-01-01

    In this lecture, the dynamic processes involved in field-reversed configuration (FRC) formation, translation, and compression will be reviewed. Though the FRC is related to the field-reversed mirror concept, the formation method used in most experiments is a variant of the field-reversed THETA-pinch. Formation of the FRC eqilibrium occurs rapidly, usually in less than 20 ..mu..s. The formation sequence consists of several coupled processes: preionization; radial implosion and compression; magnetic field line closure; axial contraction; equilibrium formation. Recent experiments and theory have led to a significantly improved understanding of these processes; however, the experimental method still relies on a somewhat empirical approach which involves the optimization of initial preionization plasma parameters and symmetry. New improvements in FRC formation methods include the use of lower voltages which extrapolate better to larger devices. The axial translation of compact toroid plasmas offers an attractive engineering convenience in a fusion reactor. FRC translation has been demonstrated in several experiments worldwide, and these plasmas are found to be robust, moving at speeds up to the Alfven velocity over distances of up to 16 m, with no degradation in the confinement. Compact toroids are ideal for magnetic compression. Translated FRCs have been compressed and heated by imploding liners. Upcoming experiments will rely on external flux compression to heat a translater FRC at 1-GW power levels. 39 refs.

  1. High Temperature Reverse By-Pass Diodes Bias and Failures | Department...

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

    Reverse By-Pass Diodes Bias and Failures High Temperature Reverse By-Pass Diodes Bias and ... US & Japan TG 4 Activities of QA Forum Thermal Reliability Study of Bypass Diodes in ...

  2. Reversible CO Binding in Metal-Organic Frameworks | Center for Gas

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

    SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Reversible CO Binding in Metal-Organic Frameworks

  3. Reversible Acid Gas Capture Using CO2-Binding Organic Liquids

    SciTech Connect (OSTI)

    Heldebrant, David J.; Koech, Phillip K.; Yonker, Clement R.; Rainbolt, James E.; Zheng, Feng

    2010-08-31

    Acid gas scrubbing technology is predominantly aqueous alkanolamine based. Of the acid gases, CO2, H2S and SO2 have been shown to be reversible, however there are serious disadvantages with corrosion and high regeneration costs. The primary scrubbing system composed of monoethanolamine is limited to 30% by weight because of the highly corrosive solution. This gravimetric limitation limits the CO2 volumetric (?108 g/L) and gravimetric capacity (?7 wt%) of the system. Furthermore the scrubbing system has a large energy penalty from pumping and heating the excess water required to dissolve the MEA bicarbonate salt. Considering the high specific heat of water (4 j/g-1K-1), low capacities and the high corrosion we set out to design a fully organic solvent that can chemically bind all acid gases i.e. CO2 as reversible alkylcarbonate ionic liquids or analogues thereof. Having a liquid acid gas carrier improves process economics because there is no need for excess solvent to pump and to heat. We have demonstrated illustrated in Figure 1, that CO2-binding organic liquids (CO2BOLs) have a high CO2 solubility paired with a much lower specific heat (<1.5 J/g-1K-1) than aqueous systems. CO2BOLs are a subsection of a larger class of materials known as Binding Organic Liquids (BOLs). Our BOLs have been shown to reversibly bind and release COS, CS2, and SO2, which we denote COSBOLS, CS2BOLs and SO2BOLs. Our BOLs are highly tunable and can be designed for post or pre-combustion gas capture. The design and testing of the next generation zwitterionic CO2BOLs and SO2BOLs are presented.

  4. Reversible Bending Fatigue Testing on Zry-4 Surrogate Rods

    SciTech Connect (OSTI)

    Wang, Jy-An John; Wang, Hong; Bevard, Bruce Balkcom; Howard, Rob L

    2014-01-01

    Testing high-burnup spent nuclear fuel (SNF) presents many challenges in areas such as specimen preparation, specimen installation, mechanical loading, load control, measurements, data acquisition, and specimen disposal because these tasks are complicated by the radioactivity of the test specimens. Research and comparison studies conducted at Oak Ridge National Laboratory (ORNL) resulted in a new concept in 2010 for a U-frame testing setup on which to perform hot-cell reversible bending fatigue testing. Subsequently, the three-dimensional finite element analysis and the engineering design of components were completed. In 2013 the ORNL team finalized the upgrade of the U-frame testing setup and the integration of the U-frame setup into a Bose dual linear motor test bench to develop a cyclic integrated reversible-bending fatigue tester (CIRFT). A final check was conducted on the CIRFT test system in August 2013, and the CIRFT was installed in the hot cell in September 2013 to evaluate both the static and dynamic mechanical response of SNF rods under simulated loads. The fatigue responses of Zircaloy-4 (Zry-4) cladding and the role of pellet pellet and pellet clad interactions are critical to SNF vibration integrity, but such data are not available due to the unavailability of an effective testing system. While the deployment of the developed CIRFT test system in a hot cell will provide the opportunity to generate the data, the use of a surrogate rod has proven quite effective in identifying the underlying deformation mechanism of an SNF composite rod under an equivalent loading condition. This paper presents the experimental results of using surrogate rods under CIRFT reversible cyclic loading. Specifically, monotonic and cyclic bending tests were conducted on surrogate rods made of a Zry-4 tube and alumina pellet inserts, both with and without an epoxy bond.

  5. Error-field penetration in reversed magnetic shear configurations

    SciTech Connect (OSTI)

    Wang, H. H.; Wang, Z. X.; Wang, X. Q. [MOE Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)] [MOE Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Wang, X. G. [School of Physics, Peking University, Beijing 100871 (China)] [School of Physics, Peking University, Beijing 100871 (China)

    2013-06-15

    Error-field penetration in reversed magnetic shear (RMS) configurations is numerically investigated by using a two-dimensional resistive magnetohydrodynamic model in slab geometry. To explore different dynamic processes in locked modes, three equilibrium states are adopted. Stable, marginal, and unstable current profiles for double tearing modes are designed by varying the current intensity between two resonant surfaces separated by a certain distance. Further, the dynamic characteristics of locked modes in the three RMS states are identified, and the relevant physics mechanisms are elucidated. The scaling behavior of critical perturbation value with initial plasma velocity is numerically obtained, which obeys previously established relevant analytical theory in the viscoresistive regime.

  6. Overview of results from the MST reversed field pinch experiment

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

    38 Please note that terms and conditions apply. Overview of results from the MST reversed field pinch experiment View the table of contents for this issue, or go to the journal homepage for more 2015 Nucl. Fusion 55 104006 (http://iopscience.iop.org/0029-5515/55/10/104006) Home Search Collections Journals About Contact us My IOPscience | International Atomic Energy Agency Nuclear Fusion Nucl. Fusion 55 (2015) 104006 (8pp) doi:10.1088/0029-5515/55/10/104006 Overview of results from the MST

  7. Overview of results from the MST reversed field pinch experiment

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

    results from the MST reversed field pinch experiment This content has been downloaded from IOPscience. Please scroll down to see the full text. Download details: IP Address: 128.104.165.63 This content was downloaded on 26/09/2013 at 15:57 Please note that terms and conditions apply. 2013 Nucl. Fusion 53 104017 (http://iopscience.iop.org/0029-5515/53/10/104017) View the table of contents for this issue, or go to the journal homepage for more Home Search Collections Journals About Contact us My

  8. New Limit on Time-Reversal Violation in Beta Decay

    SciTech Connect (OSTI)

    Mumm, H. P.; Chupp, T. E.; Cooper, R. L.; Coulter, K. P.; Freedman, S. J.; Fujikawa, B. K.; Garcia, A.; Jones, G. L.; Nico, J. S.; Thompson, A. K.; Trull, C. A.; Wietfeldt, F. E.; Wilkerson, J. F.

    2011-09-02

    We report the results of an improved determination of the triple correlation DP{center_dot}(p{sub e}xp{sub v}) that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the standard model. Our result is D=[-0.96{+-}1.89(stat){+-}1.01(sys)]x10{sup -4}. The corresponding phase between g{sub A} and g{sub V} is {phi}{sub AV}=180.013 deg. {+-}0.028 deg. (68% confidence level). This result represents the most sensitive measurement of D in nuclear {beta} decay.

  9. First-Principles Prediction of Thermodynamically Reversible Hydrogen

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

    Storage Reactions in the Li-Mg-Ca-B-H system | Energy Frontier Research Centers First-Principles Prediction of Thermodynamically Reversible Hydrogen Storage Reactions in the Li-Mg-Ca-B-H system Home Author: V. Ozolins, E. H. Majzoub, C. Wolverton Year: 2009 Abstract: Introduction of economically viable hydrogen cars is hindered by the need to store large amounts of hydrogen. Metal borohydrides [LiBH4, Mg(BH4)2, Ca(BH4)2] are attractive candidates for onboard storage because they contain high

  10. Highly-Selective and Reversible O2 Binding in

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

    Cr3(1,3,5-benzenetricarboxylate)2 | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Highly-Selective and Reversible O2 Binding in Cr3(1,3,5-benzenetricarboxylate)2 Previous Next List Leslie J. Murray, Mircea Dinca, Junko Yano, Sachin Chavan, Silvia Bordiga, Craig M. Brown and Jeffrey R. Long, J. Am. Chem. Soc., 2010, 132 (23), pp 7856-7857 DOI: 10.1021/ja1027925 Abstract Image Abstract: Reaction of Cr(CO)6 with trimesic acid in DMF affords the metal-organic

  11. Synthesis and magnetic reversal of bi-conical Ni nanostructures

    SciTech Connect (OSTI)

    Biziere, N.; Lassalle Ballier, R.; Viret, M.

    2011-09-15

    Template synthesis in polyethylene terephthalate (PET) membranes has been used to grow hour glass shaped nickel nanowires with a constriction in the range of tens of nanometers at the center. Anisotropic magnetoresistance measurements have been performed on a single nanowire to follow magnetization reversal of the structure. The results are explained via 3D micromagnetic simulations showing the appearance of a complex vortex state close to the constriction whose propagation depends on the angle between the cone axis and the applied field. The interest of this original growth process for spintronics is discussed.

  12. Magnetic excitations in the spin-1/2 triangular-lattice antiferromagnet Cs2CuBr4

    SciTech Connect (OSTI)

    Zvyagin, S. A.; Ozerov, M.; Kamenskyi, D.; Wosnitza, J.; Krzystek, J.; Yoshizawa, D.; Hagiwara, M.; Hu, Rongwei; Ryu, Hyejin; Petrovic, C.; Zhitomirsky, M. E.

    2015-11-27

    We present on high- field electron spin resonance (ESR) studies of magnetic excitations in the spin- 1/2 triangular-lattice antiferromagnet Cs2CuBr4. Frequency- field diagrams of ESR excitations are measured for different orientations of magnetic fields up to 25 T. We show that the substantial zero- field energy gap, Δ ≈ 9.5 K, observed in the low-temperature excitation spectrum of Cs2CuBr4 [Zvyagin et al:, Phys. Rev. Lett. 112, 077206 (2014)], is present well above TN. Noticeably, the transition into the long-range magnetically ordered phase does not significantly affect the size of the gap, suggesting that even below TN the high-energy spin dynamics in Cs2CuBr4 is determined by short-range-order spin correlations. The experimental data are compared with results of model spin-wave-theory calculations for spin-1/2 triangle-lattice antiferromagnet.

  13. Semi-Implicit Reversible Algorithms for Rigid Body Rotational Dynamics

    SciTech Connect (OSTI)

    Nukala, Phani K; Shelton Jr, William Allison

    2006-09-01

    This paper presents two semi-implicit algorithms based on splitting methodology for rigid body rotational dynamics. The first algorithm is a variation of partitioned Runge-Kutta (PRK) methodology that can be formulated as a splitting method. The second algorithm is akin to a multiple time stepping scheme and is based on modified Crouch-Grossman (MCG) methodology, which can also be expressed as a splitting algorithm. These algorithms are second-order accurate and time-reversible; however, they are not Poisson integrators, i.e., non-symplectic. These algorithms conserve some of the first integrals of motion, but some others are not conserved; however, the fluctuations in these invariants are bounded over exponentially long time intervals. These algorithms exhibit excellent long-term behavior because of their reversibility property and their (approximate) Poisson structure preserving property. The numerical results indicate that the proposed algorithms exhibit superior performance compared to some of the currently well known algorithms such as the Simo-Wong algorithm, Newmark algorithm, discrete Moser-Veselov algorithm, Lewis-Simo algorithm, and the LIEMID[EA] algorithm.

  14. Dual capacity compressor with reversible motor and controls arrangement therefor

    DOE Patents [OSTI]

    Sisk, Francis J. (Washington Township, Fayette County, PA)

    1980-12-02

    A hermetic reciprocating compressor such as may be used in heat pump applications is provided for dual capacity operation by providing the crankpin of the crankshaft with an eccentric ring rotatably mounted thereon, and with the end of the connecting rod opposite the piston encompassing the outer circumference of the eccentric ring, with means limiting the rotation of the eccentric ring upon the crankpin between one end point and an opposite angularly displaced end point to provide different values of eccentricity depending upon which end point the eccentric ring is rotated to upon the crankpin, and a reversible motor in the hermetic shell of the compressor for rotating the crankshaft, the motor operating in one direction effecting the angular displacement of the eccentric ring relative to the crankpin to the one end point, and in the opposite direction effecting the angular displacement of the eccentric ring relative to the crankpin to the opposite end point, this arrangement automatically giving different stroke lengths depending upon the direction of motor rotation. The mechanical structure of the arrangement may take various forms including at least one in which any impact of reversal is reduced by utilizing lubricant passages and chambers at the interface area of the crankpin and eccentric ring to provide a dashpot effect. In the main intended application of the arrangement according to the invention, that is, in a refrigerating or air conditioning system, it is desirable to insure a delay during reversal of the direction of compressor operation. A control arrangement is provided in which the control system controls the direction of motor operation in accordance with temperature conditions, the system including control means for effecting operation in a low capacity direction or alternatively in a high capacity direction in response to one set, and another set, respectively, of temperature conditions and with timer means delaying a restart of the compressor motor for at least a predetermined time in response to a condition of the control means operative to initiate a change in the operating direction of the compressor when it restarts.

  15. Neutron inelastic scattering investigation of the magnetic excitations in Cu{sub 2}Te{sub 2}O{sub 5}X{sub 2} (X=Br,Cl)

    SciTech Connect (OSTI)

    Crowe, S.J.; Majumdar, S.; Lees, M.R.; Paul, D. McK.; Bewley, R.I.; Levett, S.J.; Ritter, C.

    2005-06-01

    Neutron inelastic scattering investigations have been performed on the spin tetrahedral system Cu{sub 2}Te{sub 2}O{sub 5}X{sub 2} (X=Cl,Br). We report the observation of magnetic excitations with a dispersive component in both compounds, associated with the three-dimensional incommensurate magnetic order that develops below T{sub N}{sup Cl}=18.2 K and T{sub N}{sup Br}=11.4 K. The excitation in Cu{sub 2}Te{sub 2}O{sub 5}Cl{sub 2} softens as the temperature approaches T{sub N}{sup Cl}, leaving diffuse quasi-elastic scattering above the transition temperature. In the bromide, the excitations are present well above T{sub N}{sup Br}, which might be attributed to the presence of a degree of low dimensional correlations above T{sub N}{sup Br} in this compound.

  16. Reducing collective quantum state rotation errors with reversible dephasing

    SciTech Connect (OSTI)

    Cox, Kevin C.; Norcia, Matthew A.; Weiner, Joshua M.; Bohnet, Justin G.; Thompson, James K.

    2014-12-29

    We demonstrate that reversible dephasing via inhomogeneous broadening can greatly reduce collective quantum state rotation errors, and observe the suppression of rotation errors by more than 21?dB in the context of collective population measurements of the spin states of an ensemble of 2.110{sup 5} laser cooled and trapped {sup 87}Rb atoms. The large reduction in rotation noise enables direct resolution of spin state populations 13(1) dB below the fundamental quantum projection noise limit. Further, the spin state measurement projects the system into an entangled state with 9.5(5) dB of directly observed spectroscopic enhancement (squeezing) relative to the standard quantum limit, whereas no enhancement would have been obtained without the suppression of rotation errors.

  17. Adiabatic model and design of a translating field reversed configuration

    SciTech Connect (OSTI)

    Intrator, T. P.; Siemon, R. E.; Sieck, P. E.

    2008-04-15

    We apply an adiabatic evolution model to predict the behavior of a field reversed configuration (FRC) during decompression and translation, as well as during boundary compression. Semi-empirical scaling laws, which were developed and benchmarked primarily for collisionless FRCs, are expected to remain valid even for the collisional regime of FRX-L experiment. We use this approach to outline the design implications for FRX-L, the high density translated FRC experiment at Los Alamos National Laboratory. A conical theta coil is used to accelerate the FRC to the largest practical velocity so it can enter a mirror bounded compression region, where it must be a suitable target for a magnetized target fusion (MTF) implosion. FRX-L provides the physics basis for the integrated MTF plasma compression experiment at the Shiva-Star pulsed power facility at Kirtland Air Force Research Laboratory, where the FRC will be compressed inside a flux conserving cylindrical shell.

  18. Nanofiltration/reverse osmosis for treatment of coproduced waters

    SciTech Connect (OSTI)

    Mondal, S.; Hsiao, C.L.; Wickramasinghe, S.R. [Colorado State University, Ft Collins, CO (United States)

    2008-07-15

    Current high oil and gas prices have lead to renewed interest in exploration of nonconventional energy sources such as coal bed methane, tar sand, and oil shale. However oil and gas production from these nonconventional sources has lead to the coproduction of large quantities of produced water. While produced water is a waste product from oil and gas exploration it is a very valuable natural resource in the arid Western United States. Thus treated produced water could be a valuable new source of water. Commercially available nanofiltration and low pressure reverse osmosis membranes have been used to treat three produced waters. The results obtained here indicate that the permeate could be put to beneficial uses such as crop and livestock watering. However minimizing membrane fouling will be essential for the development of a practical process. Field Emission Scanning Electron Microscopy imaging may be used to observe membrane fouling.

  19. Statistical Stability and Time-Reversal Imgaing in Random Media

    SciTech Connect (OSTI)

    Berryman, J; Borcea, L; Papanicolaou, G; Tsogka, C

    2002-02-05

    Localization of targets imbedded in a heterogeneous background medium is a common problem in seismic, ultrasonic, and electromagnetic imaging problems. The best imaging techniques make direct use of the eigenfunctions and eigenvalues of the array response matrix, as recent work on time-reversal acoustics has shown. Of the various imaging functionals studied, one that is representative of a preferred class is a time-domain generalization of MUSIC (MUltiple Signal Classification), which is a well-known linear subspace method normally applied only in the frequency domain. Since statistical stability is not characteristic of the frequency domain, a transform back to the time domain after first diagonalizing the array data in the frequency domain takes optimum advantage of both the time-domain stability and the frequency-domain orthogonality of the relevant eigenfunctions.

  20. Magnetization reversal driven by a spin torque oscillator

    SciTech Connect (OSTI)

    Sbiaa, R.

    2014-09-01

    Magnetization reversal of a magnetic free layer under spin transfer torque (STT) effect from a magnetic hard layer with a fixed magnetization direction and an oscillating layer is investigated. By including STT from the oscillating layer with in-plane anisotropy and orthogonal polarizer, magnetization-time dependence of free layer is determined. The results show that the frequency and amplitude of oscillations can be varied by adjusting the current density and magnetic properties. For an optimal oscillation frequency (f{sub opt}), a reduction of the switching time (t{sub 0}) of the free layer is observed. Both f{sub opt} and t{sub 0} increase with the anisotropy field of the free layer.

  1. REVERSE RADIATIVE SHOCK LASER EXPERIMENTS RELEVANT TO ACCRETING STREAM-DISK

    Office of Scientific and Technical Information (OSTI)

    IMPACT IN INTERACTING BINARIES (Journal Article) | SciTech Connect REVERSE RADIATIVE SHOCK LASER EXPERIMENTS RELEVANT TO ACCRETING STREAM-DISK IMPACT IN INTERACTING BINARIES Citation Details In-Document Search Title: REVERSE RADIATIVE SHOCK LASER EXPERIMENTS RELEVANT TO ACCRETING STREAM-DISK IMPACT IN INTERACTING BINARIES We present the first results from high-energy-density laboratory astrophysics experiments that explore the hydrodynamic and radiative properties of a reverse shock relevant

  2. Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode

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

    Operation with Low Degradation | Department of Energy for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Presented at the Department of Energy Fuel Cell Projects Kickoff Meeting, September 1 - October 1, 2009 PDF icon petri_versa%20_power_kickoff.pdf More Documents & Publications Reversible Fuel Cells Workshop Summary Report Progress on the

  3. Considerations for the use of the modified line reversal technique for gas temperature measurement

    SciTech Connect (OSTI)

    Winkleman, B.C.

    1993-06-01

    Several areas related to the successful and accurate application of modified line reversal are discussed. Initially, generalized modified line reversal equations are developed. A review of basic line reversal theory is presented followed by development of correction factors for optical system effects. Image size and their effect on accurate determinations of spectral radiances is discussed. Temperature biases introduced by image vignetting is calculated. Measured image irradiances are given.

  4. Testing the Time-Reversal Modified Universality of the Sivers Function

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Testing the Time-Reversal Modified Universality of the Sivers Function Citation Details In-Document Search Title: Testing the Time-Reversal Modified Universality of the Sivers Function We derive the time-reversal modified universality for both quark and gluon Sivers functions from the parity and time-reversal invariance of QCD. We calculate the single transverse-spin asymmetry of inclusive lepton from the decay of W bosons in polarized proton-proton

  5. Are We Heading Towards a Reversal of the Trend for Ever-Greater...

    Open Energy Info (EERE)

    Mobility? Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Are We Heading Towards a Reversal of the Trend for Ever-Greater Mobility? AgencyCompany Organization:...

  6. Magnetization reversal induced by in-plane current in Ta/CoFeB...

    Office of Scientific and Technical Information (OSTI)

    current are accordance with those for magnetization reversal by spin transfer torque originated from the spin Hall effect in the Ta layer. Authors: Zhang, C. 1 ;...

  7. MODIFIED REVERSE OSMOSIS SYSTEM FOR TREATMENT OF PRODUCED WATERS

    SciTech Connect (OSTI)

    T.M. Whitworth; Liangxiong Li

    2002-09-15

    This report describes work performed during the second year of the project ''Modified reverse osmosis system for treatment of produced waters.'' We performed two series of reverse osmosis experiments using very thin bentonite clay membranes compacted to differing degrees. The first series of 10 experiments used NaCl solutions with membranes that ranged between 0.041 and 0.064mm in thickness. Our results showed compaction of such ultra-thin clay membranes to be problematic. The thickness of the membranes was exceeded by the dimensional variation in the machined experimental cell and this is believed to have resulted in local bypassing of the membrane with a resultant decrease in solute rejection efficiency. In two of the experiments, permeate flow was varied as a percentage of the total flow to investigate results of changing permeate flow on solute rejection. In one experiment, the permeate flow was varied between 2.4 and 10.3% of the total flow with no change in solute rejection. In another experiment, the permeate flow was varied between 24.6 and 52.5% of the total flow. In this experiment, the solute rejection rate decreased as the permeate occupied greater fractions of the total flow. This suggests a maximum solute rejection efficiency for these clay membranes for a permeate flow of between 10.3 and 24.6% of the total; flow. Solute rejection was found to decrease with increasing salt concentration and ranged between 62.9% and 19.7% for chloride and between 61.5 and 16.8% for sodium. Due to problems with the compaction procedure and potential membrane bypassing, these rejection rates are probably not the upper limit for NaCl rejection by bentonite membranes. The second series of four reverse osmosis experiments was conducted with a 0.057mm-thick bentonite membrane and dilutions of a produced water sample with an original TDS of 196,250 mg/l obtained from a facility near Loco Hill, New Mexico, operated by an independent. These experiments tested the separation efficiency of the bentonite membrane for each of the dilutions. We found that membrane efficiency decreased with increasing solute concentration and with increasing TDS. The rejection of SO{sub 4}{sup 2-} was greater than Cl{sup -}. This may be because the SO{sub 4}{sup 2-} concentration was much lower than the Cl{sup -} concentration in the waters tested. The cation rejection sequence varied with solute concentration and TDS. The solute rejection sequence for multi-component solutions is difficult to predict for synthetic membranes; it may not be simple for clay membranes either. The permeate flows in our experiments were 4.1 to 5.4% of the total flow. This suggests that very thin clay membranes may be useful for some separations. Work on development of a spiral-wound clay membrane module found that it is difficult to maintain compaction of the membrane if the membrane is rolled and then inserted in the outer tube. A different design was tried using a cylindrical clay membrane and this also proved difficult to assemble with adequate membrane compaction. The next step is to form the membrane in place using hydraulic pressure on a thin slurry of clay in either water or a nonpolar organic solvent such as ethanol. Technology transfer efforts included four manuscripts submitted to peer-reviewed journals, two abstracts, and chairing a session on clays as membranes at the Clay Minerals Society annual meeting.

  8. MODIFIED REVERSE OSMOSIS SYSTEM FOR TREATMENT OF PRODUCED WATERS

    SciTech Connect (OSTI)

    T.M. Whitworth; Liangxiong Li

    2002-09-15

    This report describes work performed during the first year of the project ''Modified Reverse Osmosis System for Treatment of Produced Waters.'' This research project has two objectives. The first objective is to test the use of clay membranes in the treatment of produced waters by reverse osmosis. The second objective is to test the ability of a system patented by the New Mexico Tech Research Foundation to remove salts from reverse osmosis waste streams as a solid. We performed 12 experiments using clay membranes in cross-flow experimental cells. We found that, due to dispersion in the porous frit used adjacent to the membrane, the concentration polarization layer seems to be completely (or nearly completely) destroyed at low flow rates. This observation suggests that clay membranes used with porous frit material many reach optimum rejection rates at lower pumping rates than required for use with synthetic membranes. The solute rejection efficiency decreases with increasing solution concentration. For the membranes and experiments reported here, the rejection efficiency ranged from 71% with 0.01 M NaCl solution down to 12% with 2.3 M NaCl solution. More compacted clay membranes will have higher rejection capabilities. The clay membranes used in our experiments were relatively thick (approximately 0.5 mm). The active layer of most synthetic membranes is only 0.04 {micro}m (0.00004 mm), approximately 1250 times thinner than the clay membranes used in these experiments. Yet clay membranes as thin as 12 {micro}m have been constructed (Fritz and Eady, 1985). Since Darcy's law states that the flow through a material of constant permeability is inversely proportional to it's the material's thickness, then, based on these experimental observations, a very thin clay membrane would be expected to have much higher flow rates than the ones used in these experiments. Future experiments will focus on testing very thin clay membranes. The membranes generally exhibited reasonable stable rejection rates over time for chloride for a range of concentrations between 0.01 and 2.5 M. One membrane ran in excess of three months with no apparent loss of usability. This suggests that clay membranes may have a long useable life. Twenty different hyperfiltration-induced solute precipitation experiments were either attempted or completed and are reported here. The results of these experiments suggest that hyperfiltration-induced solute precipitation is possible, even for very soluble substances such as NaCl. However, the precipitation rates obtained in the laboratory do not appear to be adequate for commercial application at this time. Future experiments will focus on making the clay membranes more compact and thinner in order to obtain higher flux rates. Two alternative methods of removing solutes from solution, for which the New Mexico Tech Research Foundation is preparing patent applications, are also being investigated. These methods will be described in the next annual report after the patent applications are filed. Technology transfer efforts included two meetings (one in Farmington NM, and one in Hobbs, NM) where the results of this research were presented to independent oil producers and other interested parties. In addition, members of the research team gave seven presentations concerning this research and because of this research project T. M. (Mike) Whitworth was asked to sit on the advisory board for development of a new water treatment facility for the City of El Paso, Texas. Several papers are in preparation for submission to peer-reviewed journals based on the data presented in this report.

  9. Compact Reversed-Field Pinch Reactors (CRFPR): preliminary engineering considerations

    SciTech Connect (OSTI)

    Hagenson, R.L.; Krakowski, R.A.; Bathke, C.G.; Miller, R.L.; Embrechts, M.J.; Schnurr, N.M.; Battat, M.E.; LaBauve, R.J.; Davidson, J.W.

    1984-08-01

    The unique confinement physics of the Reversed-Field Pinch (RFP) projects to a compact, high-power-density fusion reactor that promises a significant reduction in the cost of electricity. The compact reactor also promises a factor-of-two reduction in the fraction of total cost devoted to the reactor plant equipment (i.e., fusion power core (FPC) plus support systems). In addition to operational and developmental benefits, these physically smaller systems can operate economically over a range of total power output. After giving an extended background and rationale for the compact fusion approaches, key FPC subsystems for the Compact RFP Reactor (CRFPR) are developed, designed, and integrated for a minimum-cost, 1000-MWe(net) system. Both the problems and promise of the compact, high-power-density fusion reactor are quantitatively evaluated on the basis of this conceptual design. The material presented in this report both forms a framework for a broader, more expanded conceptual design as well as suggests directions and emphases for related research and development.

  10. Two-dimensional interpreter for field-reversed configurations

    SciTech Connect (OSTI)

    Steinhauer, Loren

    2014-08-15

    An interpretive method is developed for extracting details of the fully two-dimensional (2D) “internal” structure of field-reversed configurations (FRC) from common diagnostics. The challenge is that only external and “gross” diagnostics are routinely available in FRC experiments. Inferring such critical quantities as the poloidal flux and the particle inventory has commonly relied on a theoretical construct based on a quasi-one-dimensional approximation. Such inferences sometimes differ markedly from the more accurate, fully 2D reconstructions of equilibria. An interpreter based on a fully 2D reconstruction is needed to enable realistic within-the-shot tracking of evolving equilibrium properties. Presented here is a flexible equilibrium reconstruction with which an extensive data base of equilibria was constructed. An automated interpreter then uses this data base as a look-up table to extract evolving properties. This tool is applied to data from the FRC facility at Tri Alpha Energy. It yields surprising results at several points, such as the inferences that the local β (plasma pressure/external magnetic pressure) of the plasma climbs well above unity and the poloidal flux loss time is somewhat longer than previously thought, both of which arise from full two-dimensionality of FRCs.

  11. Multichannel optical diagnostic system for field-reversed configuration plasmas

    SciTech Connect (OSTI)

    Takahashi, Tsutomu; Gota, Hiroshi; Fujino, Toshiyuki; Okada, Masanori; Asai, Tomohiko; Fujimoto, Kayoko; Ohkuma, Yasunori; Nogi, Yasuyuki

    2004-12-01

    A constructed diagnostic system consisting of a 60-channel set of optical detectors with flexible viewing configurations is realized to investigate three-dimensional magnetohydrodynamic (MHD) motions and the internal structure of a field-reversed configuration (FRC) plasma. The system can detect radiation from the plasma in the wavelength range of 420-820 nm. Optical filters are used to select the wavelength ranges required in the experiment. The sensitivities of all the optical detectors are calibrated using radiation from the FRC plasma at a quiescent phase. Radiation profiles measured by orthogonal viewing configuration of the detectors are shown at three toroidal cross sections. From these profiles, the time evolution of the three-dimensional MHD motion of the plasma is depicted. The radiation profile measured by a one-dimensional viewing configuration yields not only an electron density profile inside the separatrix but also the width of an edge-layer plasma. A bright halo around the edge-layer plasma is observed using a Balmer-{alpha} line filter. The orthogonal viewing configuration can also be used to analyze the internal structure of the FRC. The deviated position of the major axis is estimated from the comparison between the measured radiation profiles and the nonconcentric density profile based on the rigid rotor profile model.

  12. Advances in the numerical modeling of field-reversed configurations

    SciTech Connect (OSTI)

    Belova, Elena V.; Davidson, Ronald C.; Ji, Hantao; Yamada, Masaaki

    2006-05-15

    The field-reversed configuration (FRC) is a compact torus with little or no toroidal magnetic field. A theoretical understanding of the observed FRC equilibrium and stability properties presents significant challenges due to the high plasma beta, plasma flows, large ion gyroradius, and the stochasticity of the particle orbits. Advanced numerical simulations are generally required to describe and understand the detailed behavior of FRC plasmas. Results of such simulations are presented in this paper. It is shown that 3D nonlinear hybrid simulations using the HYM code [E. V. Belova et al., Phys. Plasmas 7, 4996 (2000)] reproduce all major experimentally observed stability properties of elongated (theta-pinch-formed) FRCs. Namely, the scaling of the growth rate of the n=1 tilt mode with the S*/E parameter (S* is the FRC kinetic parameter, E is elongation, and n is toroidal mode number), the nonlinear saturation of the tilt mode, ion toroidal spin-up, and the growth of the n=2 rotational mode have been demonstrated and studied in detail. The HYM code has also been used to study stability properties of FRCs formed by the counterhelicity spheromak merging method. A new stability regime has been found for FRCs with elongation E{approx}1, which requires a close-fitting conducting shell and energetic beam ion stabilization.

  13. Two-fluid physics and field-reversed configurations

    SciTech Connect (OSTI)

    Hakim, A.; Shumlak, U.

    2007-05-15

    In this paper, algorithms for the solution of two-fluid plasma equations are presented and applied to the study of field-reversed configurations (FRCs). The two-fluid model is more general than the often used magnetohydrodynamic (MHD) model. The model takes into account electron inertia, charge separation, and the full electromagnetic field equations, and it allows for separate electron and ion motion. The algorithm presented is the high-resolution wave propagation scheme. The wave propagation method is based on solutions to the Riemann problem at cell interfaces. Operator splitting is used to incorporate the Lorentz and electromagnetic source terms. The algorithms are benchmarked against the Geospace Environmental Modeling Reconnection Challenge problem. Equilibrium of FRC is studied. It is shown that starting from a MHD equilibrium produces a relaxed two-fluid equilibrium with strong flows at the FRC edges due to diamagnetic drift. The azimuthal electron flow causes lower-hybrid drift instabilities (LHDI), which can be captured if the ion gyroradius is well resolved. The LHDI is known to be a possible source of anomalous resistivity in many plasma configurations. LHDI simulations are performed in slab geometries and are compared to recent experimental results.

  14. Transport and equilibrium in field-reversed mirrors

    SciTech Connect (OSTI)

    Boyd, J.K.

    1982-09-01

    Two plasma models relevant to compact torus research have been developed to study transport and equilibrium in field reversed mirrors. In the first model for small Larmor radius and large collision frequency, the plasma is described as an adiabatic hydromagnetic fluid. In the second model for large Larmor radius and small collision frequency, a kinetic theory description has been developed. Various aspects of the two models have been studied in five computer codes ADB, AV, NEO, OHK, RES. The ADB code computes two dimensional equilibrium and one dimensional transport in a flux coordinate. The AV code calculates orbit average integrals in a harmonic oscillator potential. The NEO code follows particle trajectories in a Hill's vortex magnetic field to study stochasticity, invariants of the motion, and orbit average formulas. The OHK code displays analytic psi(r), B/sub Z/(r), phi(r), E/sub r/(r) formulas developed for the kinetic theory description. The RES code calculates resonance curves to consider overlap regions relevant to stochastic orbit behavior.

  15. Fusion proton diagnostic for the C-2 field reversed configuration

    SciTech Connect (OSTI)

    Magee, R. M. Clary, R.; Korepanov, S.; Smirnov, A.; Garate, E.; Knapp, K.; Tkachev, A.

    2014-11-15

    Measurements of the flux of fusion products from high temperature plasmas provide valuable insights into the ion energy distribution, as the fusion reaction rate is a very sensitive function of ion energy. In C-2, where field reversed configuration plasmas are formed by the collision of two compact toroids and partially sustained by high power neutral beam injection [M. Binderbauer et al., Phys. Rev. Lett. 105, 045003 (2010); M. Tuszewski et al., Phys. Rev. Lett. 108, 255008 (2012)], measurements of DD fusion neutron flux are used to diagnose ion temperature and study fast ion confinement and dynamics. In this paper, we will describe the development of a new 3 MeV proton detector that will complement existing neutron detectors. The detector is a large area (50?cm{sup 2}), partially depleted, ion implanted silicon diode operated in a pulse counting regime. While the scintillator-based neutron detectors allow for high time resolution measurements (?100 kHz), they have no spatial or energy resolution. The proton detector will provide 10 cm spatial resolution, allowing us to determine if the axial distribution of fast ions is consistent with classical fast ion theory or whether anomalous scattering mechanisms are active. We will describe in detail the diagnostic design and present initial data from a neutral beam test chamber.

  16. Homopolar machine for reversible energy storage and transfer systems

    DOE Patents [OSTI]

    Stillwagon, Roy E. (Ruffsdale, PA)

    1981-01-01

    A homopolar machine designed to operate as a generator and motor in reversibly storing and transferring energy between the machine and a magnetic load coil for a thermo-nuclear reactor. The machine rotor comprises hollow thin-walled cylinders or sleeves which form the basis of the system by utilizing substantially all of the rotor mass as a conductor thus making it possible to transfer substantially all the rotor kinetic energy electrically to the load coil in a highly economical and efficient manner. The rotor is divided into multiple separate cylinders or sleeves of modular design, connected in series and arranged to rotate in opposite directions but maintain the supply of current in a single direction to the machine terminals. A stator concentrically disposed around the sleeves consists of a hollow cylinder having a number of excitation coils each located radially outward from the ends of adjacent sleeves. Current collected at an end of each sleeve by sleeve slip rings and brushes is transferred through terminals to the magnetic load coil. Thereafter, electrical energy returned from the coil then flows through the machine which causes the sleeves to motor up to the desired speed in preparation for repetition of the cycle. To eliminate drag on the rotor between current pulses, the brush rigging is designed to lift brushes from all slip rings in the machine.

  17. Reversible rigid coupling apparatus and method for borehole seismic transducers

    DOE Patents [OSTI]

    Owen, Thomas E. (Helotes, TX); Parra, Jorge O. (Helotes, TX)

    1992-01-01

    An apparatus and method of high resolution reverse vertical seismic profile (VSP) measurements is shown. By encapsulating the seismic detector and heaters in a meltable substance (such as wax), the seismic detector can be removably secured in a borehole in a manner capable of measuring high resolution signals in the 100 to 1000 hertz range and higher. The meltable substance is selected to match the overall density of the detector package with the underground formation, yet still have relatively low melting point and rigid enough to transmit vibrations to accelerometers in the seismic detector. To minimize voids in the meltable substance upon solidification, the meltable substance is selected for minimum shrinkage, yet still having the other desirable characteristics. Heaters are arranged in the meltable substance in such a manner to allow the lowermost portion of the meltable substance to cool and solidify first. Solidification continues upwards from bottom-to-top until the top of the meltable substance is solidified and the seismic detector is ready for use. To remove, the heaters melt the meltable substance and the detector package is pulled from the borehole.

  18. A chopper system for shortening the duration of pulsed supersonic beams seeded with NO or Br{sub 2} down to 13 μs

    SciTech Connect (OSTI)

    Lam, Jessica; Rennick, Christopher J.; Softley, Timothy P.

    2015-05-15

    A chopper wheel construct is used to shorten the duration of a molecular beam to 13 μs. Molecular beams seeded with NO or with Br{sub 2} and an initial pulse width of ≥200 μs were passed through a spinning chopper wheel, which was driven by a brushless DC in vacuo motor at a range of speeds, from 3000 rpm to 80 000 rpm. The resulting duration of the molecular-beam pulses measured at the laser detection volume ranged from 80 μs to 13 μs and was the same for both NO and Br{sub 2}. The duration is consistent with a simple analytical model, and the minimum pulse width measured is limited by the spreading of the beam between the chopper and the detection point as a consequence of the longitudinal velocity distribution of the beam. The setup adopted here effectively eliminates buildup of background gas without the use of a differential pumping stage, and a clean narrow pulse is obtained with low rotational temperature.

  19. Design and experimental testing of the performance of an outdoor LiBr/H{sub 2}O solar thermal absorption cooling system with a cold store

    SciTech Connect (OSTI)

    Agyenim, Francis; Knight, Ian; Rhodes, Michael

    2010-05-15

    A domestic-scale prototype experimental solar cooling system has been developed based on a LiBr/H{sub 2}O absorption system and tested during the 2007 summer and autumn months in Cardiff University, UK. The system consisted of a 12 m{sup 2} vacuum tube solar collector, a 4.5 kW LiBr/H{sub 2}O absorption chiller, a 1000 l cold storage tank and a 6 kW fan coil. The system performance, as well as the performances of the individual components in the system, were evaluated based on the physical measurements of the daily solar radiation, ambient temperature, inlet and outlet fluid temperatures, mass flow rates and electrical consumption by component. The average coefficient of thermal performance (COP) of the system was 0.58, based on the thermal cooling power output per unit of available thermal solar energy from the 12 m{sup 2} Thermomax DF100 vacuum tube collector on a hot sunny day with average peak insolation of 800 W/m{sup 2} (between 11 and 13.30 h) and ambient temperature of 24 C. The system produced an electrical COP of 3.6. Experimental results prove the feasibility of the new concept of cold store at this scale, with chilled water temperatures as low as 7.4 C, demonstrating its potential use in cooling domestic scale buildings. (author)

  20. Radiative reverse shock laser experiments relevant to accretion processes in cataclysmic variables

    SciTech Connect (OSTI)

    Krauland, C. M.; Drake, R. P.; Kuranz, C. C.; Sweeney, R.; Grosskopf, M.; Klein, S.; Gillespie, R.; Keiter, P. A.; Loupias, B.; Falize, E.

    2013-05-15

    We discuss the production of radiative reverse shocks in experiments at the Omega-60 laser facility. The ability of this high-intensity laser to impart large energy densities on micron-thin foils makes it feasible to create supersonic plasma flows. Obtaining a radiative reverse shock in the laboratory requires a sufficiently fast flow (∼100 km/s) of a material whose opacity is large enough to produce energetically significant emission from experimentally achievable shocked layers. The reverse shock forms in the flow once it is impeded. This paper presents the first radiographic data of normal incidence, reverse shockwaves. These experiments are primarily motivated by the contribution of radiative reverse shock waves to the evolving dynamics of the cataclysmic variable (CV) system in which they reside. We show similarity properties to suggest that the experimental production of radiative reserve shocks in the laboratory may be scalable to such astrophysical systems.

  1. Electric Dipole Moments in Radioactive Nuclei, Tests of Time Reversal Symmetry

    SciTech Connect (OSTI)

    Auerbach, N.

    2010-11-24

    The research of radioactive nuclei opens new possibilities to study fundamental symmetries, such as time reversal and reflection symmetry. Such nuclei often provide conditions to check in an optimal way certain symmetries and the violation of such symmetries. We will discuss the possibility of obtaining improved limits on violation of time reversal symmetry using pear shaped radioactive nuclei. An effective method to test time reversal invariance in the non-strange sector is to measure parity and time reversal violating (T-P-odd) electromagnetic moments, (such as the static electric dipole moment). Parity and time reversal violating components in the nuclear force may produce P-T-odd moments in nuclei which in turn induce such moments in atoms. We will discuss the possibility that in some reflection asymmetric, heavy nuclei (which are radioactive) these moments are enhanced by several orders of magnitude. Present and future experiments, which will test this idea, will be mentioned.

  2. Phenomenology of reverse-shock emission in the optical afterglows of gamma-ray bursts

    SciTech Connect (OSTI)

    Japelj, J.; Kopa?, D.; Gomboc, A. [Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, SI-1000 Ljubljana (Slovenia); Kobayashi, S.; Harrison, R.; Virgili, F. J.; Mundell, C. G. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool, L3 5RF (United Kingdom); Guidorzi, C. [Physics Departments, University of Ferrara, via Saragat 1, I-44122, Ferrara (Italy); Melandri, A., E-mail: jure.japelj@fmf.uni-lj.si, E-mail: andreja.gomboc@fmf.uni-lj.si [INAF Osservatorio Astronomico di Brera, via E. Bianchi 46, I-23807 Merate (Italy)

    2014-04-20

    We use a parent sample of 118 gamma-ray burst (GRB) afterglows, with known redshift and host galaxy extinction, to separate afterglows with and without signatures of dominant reverse-shock (RS) emission and to determine which physical conditions lead to a prominent reverse-shock emission. We identify 10 GRBs with reverse-shock signatures: 990123, 021004, 021211, 060908, 061126, 080319B, 081007, 090102, 090424, and 130427A. By modeling their optical afterglows with reverse- and forward-shock analytic light curves and using Monte Carlo simulations, we estimate the parameter space of the physical quantities describing the ejecta and circumburst medium. We find that physical properties cover a wide parameter space and do not seem to cluster around any preferential values. Comparing the rest-frame optical, X-ray, and high-energy properties of the larger sample of non-RS-dominated GRBs, we show that the early-time (<1 ks) optical spectral luminosity, X-ray afterglow luminosity, and ?-ray energy output of our reverse-shock dominated sample do not differ significantly from the general population at early times. However, the GRBs with dominant reverse-shock emission have fainter than average optical forward-shock emission at late times (>10 ks). We find that GRBs with an identifiable reverse-shock component show a high magnetization parameter R {sub B} = ?{sub B,r}/?{sub B,f} ? 2-10{sup 4}. Our results are in agreement with the mildly magnetized baryonic jet model of GRBs.

  3. Estimation of steady-state and transcient power distributions for the RELAP analyses of the 1963 loss-of-flow and loss-of-pressure tests at BR2.

    SciTech Connect (OSTI)

    Dionne, B.; Tzanos, C. P.

    2011-05-23

    To support the safety analyses required for the conversion of the Belgian Reactor 2 (BR2) from highly-enriched uranium (HEU) to low-enriched uranium (LEU) fuel, the simulation of a number of loss-of-flow tests, with or without loss of pressure, has been undertaken. These tests were performed at BR2 in 1963 and used instrumented fuel assemblies (FAs) with thermocouples (TC) imbedded in the cladding as well as probes to measure the FAs power on the basis of their coolant temperature rise. The availability of experimental data for these tests offers an opportunity to better establish the credibility of the RELAP5-3D model and methodology used in the conversion analysis. In order to support the HEU to LEU conversion safety analyses of the BR2 reactor, RELAP simulations of a number of loss-of-flow/loss-of-pressure tests have been undertaken. Preliminary analyses showed that the conservative power distributions used historically in the BR2 RELAP model resulted in a significant overestimation of the peak cladding temperature during the transient. Therefore, it was concluded that better estimates of the steady-state and decay power distributions were needed to accurately predict the cladding temperatures measured during the tests and establish the credibility of the RELAP model and methodology. The new approach ('best estimate' methodology) uses the MCNP5, ORIGEN-2 and BERYL codes to obtain steady-state and decay power distributions for the BR2 core during the tests A/400/1, C/600/3 and F/400/1. This methodology can be easily extended to simulate any BR2 core configuration. Comparisons with measured peak cladding temperatures showed a much better agreement when power distributions obtained with the new methodology are used.

  4. LATE SPECTRAL EVOLUTION OF THE EJECTA AND REVERSE SHOCK IN SN 1987A

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect LATE SPECTRAL EVOLUTION OF THE EJECTA AND REVERSE SHOCK IN SN 1987A Citation Details In-Document Search Title: LATE SPECTRAL EVOLUTION OF THE EJECTA AND REVERSE SHOCK IN SN 1987A We present observations with the Very Large Telescope and Hubble Space Telescope (HST) of the broad emission lines from the inner ejecta and reverse shock of SN 1987A from 1999 February until 2012 January (days 4381-9100 after explosion). We detect broad lines from H{alpha},

  5. U.S. DEPARTMENT OF ENERGY'S REPLY BRIEF IN SUPPORT OF REVIEW AND REVERSAL

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

    OF THE BOARD'S RULING ON THE MOTION TO WITHDRAW | Department of Energy DEPARTMENT OF ENERGY'S REPLY BRIEF IN SUPPORT OF REVIEW AND REVERSAL OF THE BOARD'S RULING ON THE MOTION TO WITHDRAW U.S. DEPARTMENT OF ENERGY'S REPLY BRIEF IN SUPPORT OF REVIEW AND REVERSAL OF THE BOARD'S RULING ON THE MOTION TO WITHDRAW U.S. DEPARTMENT OF ENERGY'S REPLY BRIEF IN SUPPORT OF REVIEW AND REVERSAL OF THE Nuclear Regulatory Commission's Atomic Safety and Licensing Board's (BOARD) RULING ON THE MOTION TO

  6. A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic disks: distorted viscous vortex

    SciTech Connect (OSTI)

    Gilbert, Dustin A.; Ye, Li; Varea, Aïda; Agramunt-Puig, Sebastià; del Valle, Nuria; Navau, Carles; López-Barbera, José Francisco; Buchanan, Kristen S.; Hoffmann, Axel; Sánchez, Alvar; Sort, Jordi; Liu, Kai; Nogués, Josep

    2015-04-28

    Magnetic vortices have generated intense interest in recent years due to their unique reversal mechanisms, fascinating topological properties, and exciting potential applications. In addition, the exchange coupling of magnetic vortices to antiferromagnets has also been shown to lead to a range of novel phenomena and functionalities. Here we report a new magnetization reversal mode of magnetic vortices in exchange coupled Ir20Mn80/Fe20Ni80 microdots: distorted viscous vortex reversal. In contrast to the previously known or proposed reversal modes, the vortex is distorted close to the interface and viscously dragged due to the uncompensated spins of a thin antiferromagnet, which leads to unexpected asymmetries in the annihilation and nucleation fields. These results provide a deeper understanding of the physics of exchange coupled vortices and may also have important implications for applications involving exchange coupled nanostructures.

  7. Colorado - C.R.S. 36-1-136 - Rights of Way Granted - Reversion...

    Open Energy Info (EERE)

    search OpenEI Reference LibraryAdd to library Legal Document- StatuteStatute: Colorado - C.R.S. 36-1-136 - Rights of Way Granted - ReversionLegal Abstract This section covers the...

  8. Pairing state with a time-reversal symmetry breaking in FeAs...

    Office of Scientific and Technical Information (OSTI)

    in FeAs-based superconductors Citation Details In-Document Search Title: Pairing state with a time-reversal symmetry breaking in FeAs-based superconductors You are ...

  9. Pairing state with a time-reversal symmetry breaking in FeAs-based

    Office of Scientific and Technical Information (OSTI)

    superconductors (Technical Report) | SciTech Connect Technical Report: Pairing state with a time-reversal symmetry breaking in FeAs-based superconductors Citation Details In-Document Search Title: Pairing state with a time-reversal symmetry breaking in FeAs-based superconductors We investigate the competition between the extended s{+-} wave and dx2-y2 -wave pairing order parameters in the iron-based superconductors. Because of the frustrating pairing interactions among the electron and the

  10. Real-time sub- Å ngstrom imaging of reversible and irreversible

    Office of Scientific and Technical Information (OSTI)

    conformations in rhodium catalysts and graphene (Journal Article) | DOE PAGES Real-time sub- Å ngstrom imaging of reversible and irreversible conformations in rhodium catalysts and graphene Title: Real-time sub- Å ngstrom imaging of reversible and irreversible conformations in rhodium catalysts and graphene Authors: Kisielowski, Christian ; Wang, Lin-Wang ; Specht, Petra ; Calderon, Hector A. ; Barton, Bastian ; Jiang, Bin ; Kang, Joo H. ; Cieslinski, Robert Publication Date: 2013-07-29

  11. Real-time sub- Å ngstrom imaging of reversible and irreversible

    Office of Scientific and Technical Information (OSTI)

    conformations in rhodium catalysts and graphene (Journal Article) | DOE PAGES Real-time sub- Å ngstrom imaging of reversible and irreversible conformations in rhodium catalysts and graphene Title: Real-time sub- Å ngstrom imaging of reversible and irreversible conformations in rhodium catalysts and graphene Authors: Kisielowski, Christian ; Wang, Lin-Wang ; Specht, Petra ; Calderon, Hector A. ; Barton, Bastian ; Jiang, Bin ; Kang, Joo H. ; Cieslinski, Robert Publication Date: 2013-07-29

  12. FLUX ENHANCEMENT IN CROSSFLOW MEMBRANE FILTRATION: FOULING AND IT'S MINIMIZATION BY FLOW REVERSAL

    SciTech Connect (OSTI)

    Shamsuddin Ilias

    2005-01-25

    Fouling problems are perhaps the single most important reason for relatively slow acceptance of ultrafiltration in many areas of chemical and biological processing. To overcome the losses in permeate flux associated with concentration polarization and fouling in cross flow membrane filtration, we investigated the concept of flow reversal as a method to enhance membrane flux in ultrafiltration. Conceptually, flow reversal prevents the formation of stable hydrodynamic and concentration boundary layers at or near the membrane surface. Further more, periodic reversal of the flow direction of the feed stream at the membrane surface results in prevention and mitigation of membrane fouling. Consequently, these advantages are expected to enhance membrane flux significantly. A crossflow membrane filtration unit was designed and built to test the concept of periodic flow reversal for flux enhancement. The essential elements of the system include a crossflow hollow fiber membrane module integrated with a two-way valve to direct the feed flow directions. The two-way valve is controlled by a controller-timer for periodic reversal of flow of feed stream. Another important feature of the system is that with changing feed flow direction, the permeate flow direction is also changed to maintain countercurrent feed and permeate flows for enhanced mass transfer driving force (concentration difference). In this report, we report our application of Flow Reversal technique in clarification of apple juice containing pectin. The presence of pectin in apple juice makes the clarification process difficult and is believed to cause membrane fouling. Of all compounds found in apple juice, pectin is most often identified as the major hindrance to filtration performance. Based on our ultrafiltration experiments with apple juice, we conclude that under flow reversal conditions, the permeate flux is significantly enhanced when compared with the conventional unidirectional flow. Thus, flow reversal technology seems an attractive alternative to mitigate fouling problem in crossflow membrane filtration.

  13. Strain-assisted current-induced magnetization reversal in magnetic tunnel

    Office of Scientific and Technical Information (OSTI)

    junctions: A micromagnetic study with phase-field microelasticity (Journal Article) | SciTech Connect Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity Citation Details In-Document Search Title: Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity Effect of substrate misfit strain on current-induced in-plane

  14. Incommensurate magnetic ordering in Cu{sub 2}Te{sub 2}O{sub 5}X{sub 2} (X=Cl,Br) studied by single crystal neutron diffraction

    SciTech Connect (OSTI)

    Zaharko, O.; Roennow, H.; Mesot, J.; Crowe, S. J.; Paul, D. McK.; Brown, P. J.; Daoud-Aladine, A.; Meents, A.; Wagner, A.; Prester, M.; Berger, H.

    2006-02-01

    Polarized and unpolarized neutron-diffraction studies have been carried out on single crystals of the coupled spin tetrahedra systems Cu{sub 2}Te{sub 2}O{sub 5}X{sub 2} (X=Cl,Br). A model of the magnetic structure associated with the propagation vectors k{sup '}{sub Cl}{approx_equal}(-0.150,0.422,(1/2)) and k{sup '}{sub Br}{approx_equal}(-0.172,0.356,(1/2)) and stable below T{sub N}=18 K for X=Cl and T{sub N}=11 K for X=Br is proposed. A feature of the model, common to both the bromide and chloride, is a canted coplanar motif for the four Cu{sup 2+} spins on each tetrahedron which rotates on a helix from cell to cell following the propagation vector. The Cu{sup 2+} magnetic moment determined for X=Br,0.395(5){mu}{sub B}, is significantly less than for X=Cl,0.88(1){mu}{sub B} at 2 K. The magnetic structure of the chloride associated with the wave vector k{sup '} differs from that determined previously for the wave vector k{approx_equal}(0.150,0.422,(1/2)) [O. Zaharko et al., Phys. Rev. Lett. 93, 217206(E) (2004)].

  15. Laser Raman spectroscopy study of the zinc and bromide ion complex equilibrium in zinc/bromine battery electrolytes. [2M ZnBr/sub 2/ and 1M KBr solution

    SciTech Connect (OSTI)

    Grimes, P.G.; Larrabee, J.A.

    1985-01-01

    Laser Raman spectroscopy was used to study the zinc and bromide ion complex equilibrium in zinc bromine battery model electrolytes. Solutions of zinc bromide with added KBr, HBr and N-methyl, N-ethyl morpholinium (MEM) bromide were examined and compared. Solutions studied ranged from 1 to 3 molar in zinc and from 2.5 to 8 molar in bromide. A typical Raman spectrum of a zinc bromide solution is shown in Figure 1. Each of the zinc species is identified, Zn/sup + +/ (aq), ZnBr/sup +/, ZnBr/sub 2/ (aq), ZnBr/sub 3//sup -/ and ZnBr/sub 4//sup 2 -/. By the use of peak heights or deconvolution/integration along with published Raman cross sections, the amount of each zinc species could be quantitatively determined. The addition of bromide ions to the zinc bromide solutions will shift the equilibrium toward higher bromide complexes. The added cations will influence the shifts. It has been noted that the conductivity of the electrolyte decreases when the quaternary ammonium ions are present compared to cations such as potassium or hydrogen. Significantly more free zinc is present in zinc bromide solutions with added KBr than with either MEMBr or HBr. Shifts are also noted with the other zinc ion containing species. It appears that the quaternary ammonium ions and possibly the pH could have a stabilizing effect on zinc bromide complex ion formation. 2 figs.

  16. FLUX ENHANCEMENT IN CROSSFLOW MEMBRANE FILTRATION: FOULING AND IT'S MINIMIZATION BY FLOW REVERSAL

    SciTech Connect (OSTI)

    Shamsuddin Ilias

    2004-06-14

    Fouling problems are perhaps the single most important reason for relatively slow acceptance of ultrafiltration in many areas of chemical and biological processing. To overcome the losses in permeate flux associated with concentration polarization and fouling in cross flow membrane filtration, we investigated the concept of flow reversal as a method to enhance membrane flux in ultrafiltration. Conceptually, flow reversal prevents the formation of stable hydrodynamic and concentration boundary layers at or near the membrane surface. Further more, periodic reversal of the flow direction of the feed stream at the membrane surface results in prevention and mitigation of membrane fouling. Consequently, these advantages are expected to enhance membrane flux significantly. A crossflow membrane filtration unit was designed and built to test the concept of periodic flow reversal for flux enhancement. The essential elements of the system include a crossflow hollow fiber membrane module integrated with a two-way valve to direct the feed flow directions. The two-way valve is controlled by a controller-timer for periodic reversal of flow of feed stream. Another important feature of the system is that with changing feed flow direction, the permeate flow direction is also changed to maintain countercurrent feed and permeate flows for enhanced mass transfer driving force (concentration difference). In our previous report, we reported our work on UF of BSA. In this report, we report our continuing application of Flow Reversal technique in clarification of apple juice containing pectin. The presence of pectin in apple juice makes the clarification process difficult and is believed to cause membrane fouling. Of all compounds found in apple juice, pectin is most often identified as the major hindrance to filtration performance. Laboratory-scale tests on a hollow-fiber ultrafiltration membrane module using pectin in apple juice as feed show that under flow reversal conditions, the permeate flux is significantly enhanced when compared with the conventional unidirectional flow.

  17. Flux Enhancement in Crossflow Membrane Filtration: Fouling and It's Minimization by Flow Reversal

    SciTech Connect (OSTI)

    Shamsuddin Ilias

    2005-08-04

    Fouling problems are perhaps the single most important reason for relatively slow acceptance of ultrafiltration in many areas of chemical and biological processing. To overcome the losses in permeate flux associated with concentration polarization and fouling in cross flow membrane filtration, we investigated the concept of flow reversal as a method to enhance membrane flux in ultrafiltration. Conceptually, flow reversal prevents the formation of stable hydrodynamic and concentration boundary layers at or near the membrane surface. Further more, periodic reversal of the flow direction of the feed stream at the membrane surface results in prevention and mitigation of membrane fouling. Consequently, these advantages are expected to enhance membrane flux significantly. A crossflow membrane filtration unit was designed and built to test the concept of periodic flow reversal for flux enhancement. The essential elements of the system include a crossflow hollow fiber membrane module integrated with a two-way valve to direct the feed flow directions. The two-way valve is controlled by a controller-timer for periodic reversal of flow of feed stream. Another important feature of the system is that with changing feed flow direction, the permeate flow direction is also changed to maintain countercurrent feed and permeate flows for enhanced mass transfer driving force (concentration difference). Three feed solutions (Bovine serum albumin (BSA), apple juice and citrus fruit pectin) were studied in crossflow membrane filtration. These solutes are well-known in membrane filtration for their fouling and concentration polarization potentials. Laboratory-scale tests on a hollow-fiber ultrafiltration membrane module using each of the feed solutes show that under flow reversal conditions, the permeate flux is significantly enhanced when compared with the conventional unidirectional flow. The flux enhancement is dramatic (by an order of magnitude) with increased feed concentration and operating transmembrane pressure. Thus, flow reversal technology seems an attractive alternative to mitigate fouling problem in crossflow membrane filtration.

  18. High field strength following the Kauai R-N geomagnetic reversal

    SciTech Connect (OSTI)

    Paul, H.A. . Dept. of Geology)

    1993-04-01

    The paleomagnetism of superposed lava flows on Kauai, Hawaii shows that the ancient geomagnetic field was unusually strong following a reverse-to-normal polarity transition that occurred about 4 million years ago. Paleointensities were determined by a standard experimental procedure (Thelliers' method) that recreates the process of remanence acquisition in volcanic rocks. This experiment makes it possible to infer the strength of the geomagnetic field present with each lava flow formed, thus producing an accurate picture of the ancient field's behavior after the reversal. Samples from 10 volcanic units yielded virtual dipole moments (VDMs) ranging from 7.4 [times] 10[sup 22] Am[sup 2] to 14.5 [times] 10[sup 22] Am[sup 2] with an average of 11.1[times]10[sup 22] Am[sup 2]. This value is high in comparisons to the average VDM for the past 5 m.y., approximately 8.7[times]10[sup 22] Am[sup 2]. In contrast to the highly variable dipole moment observed following a 15 m.y. old reversal at Steen s Mountain, Oregon, the field following the Kauai transition was relatively steady. Surprisingly, the maximum dipole moments following the two reversals were nearly equal. This similarity hints that high field strength may be a systematic feature of the geodynamo immediately following a polarity reversal.

  19. Theoretical, numerical and experimental investigation of centrifugal pumps in reverse operation

    SciTech Connect (OSTI)

    Derakhshan, Shahram; Nourbakhsh, Ahmad

    2008-09-15

    When a pump works as a turbine, its hydraulic behavior will be changed. Several methods have been developed to predict the best efficiency of pumps running as turbines but their results are not in good coincidence with experimental data for all pumps. Therefore, study and investigation of hydraulic behavior of pumps in reverse operation can be useful. In this study, the best efficiency point of an industrial centrifugal pump running as turbine was achieved using a theoretical analysis. This method tries to estimate hydraulic components of reverse (turbine) mode using direct (pump) mode. In the next step, the pump was simulated in direct and reverse modes by computational fluid dynamics. 3D full Navier-Stokes equations were solved using FineTurbo V.7 flow solver. Using numerical results, complete characteristic curves of the pump in direct and reverse modes were obtained. For experimental verification of theoretical and numerical results, the pump was tested as a turbine in a test rig. All required parameters were measured to achieve complete characteristic curves of the reverse pump. The theoretical and numerical results were compared with experimental data and some other methods. (author)

  20. Magnetization reversal assisted by half antivortex states in nanostructured circular cobalt disks

    SciTech Connect (OSTI)

    Lara, A.; Aliev, F. G.; Dobrovolskiy, O. V.; Prieto, J. L.; Huth, M.

    2014-11-03

    The half antivortex, a fundamental topological structure which determines magnetization reversal of submicron magnetic devices with domain walls, has been suggested also to play a crucial role in spin torque induced vortex core reversal in circular disks. Here, we report on magnetization reversal in circular disks with nanoholes through consecutive metastable states with half antivortices. In-plane anisotropic magnetoresistance and broadband susceptibility measurements accompanied by micromagnetic simulations reveal that cobalt (Co) disks with two and three linearly arranged nanoholes directed at 45° and 135° with respect to the external magnetic field show reproducible step-like changes in the anisotropic magnetoresistance and magnetic permeability due to transitions between different intermediate states mediated by vortices and half antivortices confined to the dot nanoholes and edges, respectively. Our findings are relevant for the development of multi-hole based spintronic and magnetic memory devices.

  1. Reversible gelling culture media for in-vitro cell culture in three-dimensional matrices

    DOE Patents [OSTI]

    An, Yuehuei H. (Charleston, SC); Mironov, Vladimir A. (Mt. Pleasant, SC); Gutowska, Anna (Richland, WA)

    2000-01-01

    A gelling cell culture medium useful for forming a three dimensional matrix for cell culture in vitro is prepared by copolymerizing an acrylamide derivative with a hydrophilic comonomer to form a reversible (preferably thermally reversible) gelling linear random copolymer in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff, mixing the copolymer with an aqueous solvent to form a reversible gelling solution and adding a cell culture medium to the gelling solution to form the gelling cell culture medium. Cells such as chondrocytes or hepatocytes are added to the culture medium to form a seeded culture medium, and temperature of the medium is raised to gel the seeded culture medium and form a three dimensional matrix containing the cells. After propagating the cells in the matrix, the cells may be recovered by lowering the temperature to dissolve the matrix and centrifuging.

  2. Simulation of oscillating field current drive on the reversed-field pinch

    SciTech Connect (OSTI)

    Harned, D.S.; Schnack, D.D.; Strauss, H.R.; Nebel, R.A.

    1988-07-01

    Oscillating field current drive on the reversed-field pinch is simulated by using a three-dimensional nonlinear resistive magnetohydrodynamic model in conjunction with a one-dimensional hyper-resistive model. When input from the three-dimensional model is used for fluctuating fields in the hyper-resistive equations, the two models are found to give similar relaxed profiles. Comparisons are made with experiments on the Los Alamos National Laboratory ZT-40M reversed-field pinch device (Nucl. Fusion 25, 1321 (1985)). Simulation results indicate that the oscillation period must be much less than the resistive decay time, but should not be much less than the hyper-resistive relaxation time, in order to maintain reversal without a steady-state driving field.

  3. Multi-channel time-reversal receivers for multi and 1-bit implementations

    DOE Patents [OSTI]

    Candy, James V.; Chambers, David H.; Guidry, Brian L.; Poggio, Andrew J.; Robbins, Christopher L.

    2008-12-09

    A communication system for transmitting a signal through a channel medium comprising digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. In one embodiment a transmitter is adapted to transmit the signal, a multiplicity of receivers are adapted to receive the signal, a digitizer digitizes the signal, and a time-reversal signal processor is adapted to time-reverse the digitized signal. An embodiment of the present invention includes multi bit implementations. Another embodiment of the present invention includes 1-bit implementations. Another embodiment of the present invention includes a multiplicity of receivers used in the step of transmitting the signal through the channel medium.

  4. Ion heating and magnetohydrodynamic dynamo fluctuations in the reversed-field pinch

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

    ion heating and magnetohydrodynamic dynamo fluctuations in the reversed-field pinch Earl Scime?) Miodrag Cekic, D. J. Den Hartog, Samuel Hokin, D. J. Holly, and Christopher Watts Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 5.3 706 (Received 8 June 1992; accepted 18 August 1992) Ion temperatures have been measured in the Madison Symmetric Torus (MST) [Dexter et aL, Fusion Technol. 19, 131 ( 199 1 j] reversed-field pinch (RFP) with a five channel charge exchange

  5. Propagation direction reversal of ionization zones in the transition between high and low current magnetron sputtering

    SciTech Connect (OSTI)

    School of Materials Science and Engineering, State Key Lab for Materials Processing and Die & Mold Technology, Huazhong University of Science and Technology, Wuhan 430074, China; Department of Physics, University of California Berkeley, Berkeley, California 94720, USA; Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA; Yang, Yuchen; Liu, Jason; Liu, Lin; Anders, Andr

    2014-12-11

    Past research has revealed the propagation of dense, asymmetric ionization zones in both high and low current magnetron discharges. Here we report about the direction reversal of ionization zone propagation as observed with fast cameras. At high currents, zones move in the E B direction with velocities of 103 to 104 m/s. However at lower currents, ionization zones are observed to move in the opposite, the -E B direction, with velocities ~;; 103 m/s. It is proposed that the direction reversal is associated with the local balance of ionization and supply of neutrals in the ionization zone.

  6. Reversal of the Upper Critical Field Anisotropy and Spin-Locked

    Office of Scientific and Technical Information (OSTI)

    Superconductivity in K2Cr3As3 (Technical Report) | SciTech Connect Reversal of the Upper Critical Field Anisotropy and Spin-Locked Superconductivity in K2Cr3As3 Citation Details In-Document Search Title: Reversal of the Upper Critical Field Anisotropy and Spin-Locked Superconductivity in K2Cr3As3 Recently, superconductivity in K2Cr3As3 (Tc =6.1 K) was discovered. The crystalline lattice contains an array of weakly coupled, double well [(Cr3As3)2-]∞ linkages stretched along the c axis,

  7. Reversal of the Upper Critical Field Anisotropy and Spin-Locked

    Office of Scientific and Technical Information (OSTI)

    Superconductivity in K2Cr3As3 (Technical Report) | SciTech Connect Reversal of the Upper Critical Field Anisotropy and Spin-Locked Superconductivity in K2Cr3As3 Citation Details In-Document Search Title: Reversal of the Upper Critical Field Anisotropy and Spin-Locked Superconductivity in K2Cr3As3 × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a

  8. Absence of correlation between Sry polymorphisms and XY sex reversal caused by the M.m. domesticus Y chromosome

    SciTech Connect (OSTI)

    Carlisle, C.; Nagamine, C.M. [Vanderbilt Univ., School of Medicine, Nashville, TN (United States)] [Vanderbilt Univ., School of Medicine, Nashville, TN (United States); Winkinig, H.; Weichenhan, D. [Medizinische Universitaet Zu Luebeck (Germany)] [Medizinische Universitaet Zu Luebeck (Germany)

    1996-04-01

    Mus musculus domesticus Y chromosomes (Y{sup DOM} Chrs) vary in their ability to induce testes in the strain C57BL/6J. In severe cases, XY females develop (XY{sup DOM} sex reversal). To identify the molecular basis for the sex reversal, a 2.7-kb region of Sry, the testis-determining gene, was sequenced from Y{sup DOM} Chrs linked to normal testis determination, transient sex reversal, and severe sex reversal. Four mutations were identified. However, no correlation exists between these mutations and severity of XY{sup DOM} sex reversal. RT-PCR identified Sry transcripts in XY{sup DOM} sex-reversed fetal gonads at 11 d.p.c., the age when Sry is hypothesized to function. In addition, no correlation exists between XY{sup DOM} sex reversal and copy numbers of pSx1, a Y-repetitive sequence whose deletion is linked to XY sex reversal. We conclude that SRY protein variants, blockade of Sry transcription, and deletion of pSx1 sequences are not the underlying causes of XY{sup DOM} sex reversal. 63 refs., 6 figs., 6 tabs.

  9. Improvement of {gamma}-ray energy resolution of LaBr{sub 3}:Ce{sup 3+} scintillation detectors by Sr{sup 2+} and Ca{sup 2+} co-doping

    SciTech Connect (OSTI)

    Alekhin, M. S.; Haas, J. T. M. de; Khodyuk, I. V.; Dorenbos, P.; Kraemer, K. W.; Menge, P. R.; Ouspenski, V.

    2013-04-22

    Commercially available LaBr{sub 3}:5% Ce{sup 3+} scintillators show with photomultiplier tube readout about 2.7% energy resolution for the detection of 662 keV {gamma}-rays. Here we will show that by co-doping LaBr{sub 3}:Ce{sup 3+} with Sr{sup 2+} or Ca{sup 2+} the resolution is improved to 2.0%. Such an improvement is attributed to a strong reduction of the scintillation light losses that are due to radiationless recombination of free electrons and holes during the earliest stages (1-10 ps) inside the high free charge carrier density parts of the ionization track.

  10. High field magnetotransport and point contact Andreev reflection measurements on CuCr{sub 2}Se{sub 4} and CuCr{sub 2}Se{sub 3}BrDegenerate magnetic semiconductor single crystals

    SciTech Connect (OSTI)

    Borisov, K. Coey, J. M. D.; Stamenov, P.; Alaria, J.

    2014-05-07

    Single crystals of the metallically degenerate fully magnetic semiconductors CuCr{sub 2}Se{sub 4} and CuCr{sub 2}Se{sub 3}Br have been prepared by the Chemical Vapour Transport method, using either Se or Br as transport agents. The high-quality, millimetre-sized, octahedrally faceted, needle- and platelet-shaped crystals are characterised by means of high field magnetotransport (?{sub 0}H? 14?T) and Point Contact Andreev Reflection. The relatively high spin polarisation observed |P|>0.56, together with the relatively low minority carrier effective mass of 0.25 m{sub e}, and long scattering time 10{sup ?13}?s, could poise these materials for integration in low- and close-to-room temperature minority injection bipolar heterojunction transistor demonstrations.

  11. A field-reversed magnetic configuration and applications of high-temperature FRC plasma

    SciTech Connect (OSTI)

    Ryzhkov, S. V.

    2011-12-15

    As applied to a tokomak, a magnetic trap for confinement of a plasma with an inverted field or a magnetic field reversed configuration (FRC) is one of the most promising alternatives of the systems with high {beta}. A brief review of the latest data on FRC and potential directions of using such configurations in addition to energy generation in thermonuclear reactors (TNRs) is proposed.

  12. Confinement analyses of the high-density field-reversed configuration plasma in the field-reversed configuration experiment with a liner

    SciTech Connect (OSTI)

    Zhang Shouyin; Intrator, T.P.; Wurden, G.A.; Waganaar, W.J.; Taccetti, J.M.; Renneke, R.; Grabowski, C.; Ruden, E.L.

    2005-05-15

    The focus of the field-reversed configuration (FRC) experiment with a liner (FRX-L) is the formation of a target FRC plasma for magnetized target fusion experiments. An FRC plasma with density of 10{sup 23} m{sup -3}, total temperature in the range of 150-300 eV, and a lifetime of {approx_equal}20 {mu}s is desired. Field-reversed {theta}-pinch technology is used with programed cusp fields at {theta}-coil ends to achieve non-tearing field line reconnections during FRC formation. Well-formed FRCs with density between (2-4)x10{sup 22} m{sup -3}, lifetime in the range of 15-20 {mu}s, and total temperature between 300-500 eV are reproducibly created. Key FRC parameters have standard deviation in the mean of 10% during consecutive shots. The FRCs are formed at 50 mTorr deuterium static fill using 2 kG net reversed bias field inside the {theta}-coil confinement region, with external main field unexpectedly ranging between 15-30 kG. The high-density FRCs confinement properties are approximately in agreement with empirical scaling laws obtained from previous experiments with fill pressure mostly less than 20 mTorr. Analyses in this paper reveal that reducing the external main field modulation and/or extending the {theta}-coil length in the FRX-L device are critical in achieving higher FRC parameters for application in magnetized target fusion.

  13. Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly technical report, April 1--June 30, 1996

    SciTech Connect (OSTI)

    Hunt, T.; Sjostrom, S.; Smith, J.; Chang, R.

    1996-07-27

    The overall objective this two phase program is to investigate the use of dry carbon-based sorbents for mercury control. During Phase 1, a bench-scale field test device that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse has been designed and will be integrated with an existing pilot-scale facility at PSCo`s Comanche Station. Up to three candidate sorbents will then be injected into the flue gas stream upstream of the test device to determine the mercury removal efficiency for each sorbent. During the Phase 11 effort, component integration for the most promising dry sorbent technology (technically and economically feasible) shall be tested at the 5000 acfm pilot-scale. An extensive work plan has been developed for the project. Three sorbents will be selected for evaluation at the facility through investigation, presentation, and discussion among team members: PSCO, EPRI, ADA, and DOE. The selected sorbents will be tested in the five primary bench-scale configurations: pulse `et baghouse, TOXECON, reverse-gas baghouse, electrostatic precipitator, and an ESP or fabric filter `with no Comanche ash in the flue gas stream. In the EPRI TOXECON system, mercury sorbents will be injected downstream of a primary particulate control device, and collected in a pulse-jet baghouse operated at air-to-cloth ratios of 12 to 16 ft/min, thus separating the mercury and sorbent from the captured flyash. In the no-ash configuration, an external flyash sample will be injected into a clean gas stream to investigate possible variations in sorbent effectiveness in the presence of different ashes. The use of an existing test facility, a versatile design for the test fixture, and installation of a continuous mercury analyzer will allow for the completion of this ambitious test plan. The primary activity during the quarter was to complete fabrication and installation of the facility.

  14. Optical absorption and luminescence spectroscopy of U{sup 3+} in K{sub 2}La{ital X}{sub 5} ({ital X}=Cl,Br,I)

    SciTech Connect (OSTI)

    Andres, H.P.; Kraemer, K.; Guedel, H.

    1996-08-01

    The title compounds were synthesized and high-resolution absorption and luminescence spectra measured in the near-infrared, VIS, and near UV regions. The visible absorption spectra are dominated by very intense 5{ital f}{r_arrow}6{ital d} bands overlapping with {ital f}-{ital f} transitions. The onset of the first {ital f}-{ital d} absorption is shifted from 46000 cm{sup {minus}1} in K{sub 2}LaCl{sub 5}:Nd{sup 3+} to 15000 cm{sup {minus}1} in K{sub 2}LaCl{sub 5}:U{sup 3+}. Crystal-field splittings in corresponding {sup 2{ital S}+1}{ital L}{sub {ital J}} multiplets are greater by typically a factor of 2 in the U{sup 3+} doped crystal, thus reflecting the larger extension and stronger interaction of the 5{ital f} electrons with the ligands. {ital f}-{ital f} transitions are typically two orders of magnitude more intense in K{sub 2}LaCl{sub 5}:U{sup 3+} than in K{sub 2}LaCl{sub 5}:Nd{sup 3+}. Along the halide series K{sub 2}La{ital X}{sub 5}:U{sup 3+} ({ital X}=Cl,Br,I) the differences in the position of corresponding {ital f}-{ital d} and {ital f}-{ital f} transitions, crystal-field splittings, vibronic intensities, and excited-state lifetimes can be explained with the increasing covalency, the decreasing phonon energies, the increasing electron-phonon coupling, and the increasing U-{ital X} distances. The {ital f}-{ital d} excited states provide a nonradiative bypass of some {ital f}-{ital f} excited states in the case of all these halide lattices. The excited-state dynamics are determined by a delicate interplay of radiative and nonradiative relaxation processes, they are strongly dependent on the nature of {ital X}. Multiphonon relaxation processes are least competitive in the iodide due to the very low value of 106 cm{sup {minus}1} for the highest-energy phonons. A cross-relaxation mechanism determines the dynamics of the iodide at room temperature. {copyright} {ital 1996 The American Physical Society.}

  15. Evaluate fundamental approaches to longwall dust control: Subprogram F, Reversed drum rotation

    SciTech Connect (OSTI)

    Ludlow, J.; Kelly, J.; Ruggieri, S.

    1990-05-01

    In longwall mining, a significant portion of the shearer operator's dust exposure is caused by dust generated during loading. With the conventional direction of shearer drum rotation, loading efficiency is usually poor due to obstructions caused by the ranging arms and the cowl support arms. By reversing the normal direction of rotation, however, the arms no longer provide an obstruction. This results in improved loading efficiency and reduced dust generation. This report describes the reversed drum rotation concept and presents the results of a field survey and underground evaluation conducted to prove its feasibility and to measure its dust control benefits. Through this effort, the technique was shown to be feasible from both a mining and mechanical standpoint. During the underground test, it reduced dust levels near the shearer operator's positions by about 85%. 20 figs., 4 tabs.

  16. Advanced dimensional inspection for the reverse engineering of power plant equipment

    SciTech Connect (OSTI)

    Kotteakos, B.; Ball, K.A.

    1996-12-31

    Forced outages and critical path situations often leave electric utilities with very few options other than the OEM. What does the utility do when faced with the situation of long lead time or obsolete items necessary to bring units back on-line, or off load restrictions. At Southern California Edison Company (SCE), a proactive approach to the reverse engineering and inspection process was undertaken to reduce the effects of similar situations. Advances in dimensional measurement technology have afforded the authors` company a cost effective method for obtaining the necessary inspection data to remanufacture certain items. This paper identifies equipment utilized by SCE for the reverse engineering and inspection of turbine and turbine related components and their typical applications in the power generation industry.

  17. Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

    SciTech Connect (OSTI)

    Weber, T. E. Intrator, T. P.; Smith, R. J.

    2015-04-15

    Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ∼350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.

  18. Power balance in a high-density field reversed configuration plasma

    SciTech Connect (OSTI)

    Renneke, R. M.; Intrator, T. P.; Hsu, S. C.; Wurden, G. A.; Waganaar, W. J.; Ruden, E. L.; Grabowski, T. C.

    2008-06-15

    A global power balance analysis has been performed for the Field Reversed Experiment with Liner high density (>5x10{sup 22} m{sup -3}) field reversed configuration (FRC) plasma. The analysis was based on a zero-dimensional power balance model [D. J. Rey and M. Tuszewski, Phys. Fluids 27, 1514 (1984)]. The key findings are as follows. First, the percentage of radiative losses relative to total loss is an order of magnitude lower than previous lower density FRC experiments. Second, Ohmic heating was found to correlate with the poloidal flux trapping at FRC formation, suggesting that poloidal flux dissipation is primarily responsible for plasma heating. Third, high density FRCs analyzed in this work reinforce the low-density adiabatic scaling, which shows that particle confinement time and flux confinement time are approximately equal.

  19. ATP-independent reversal of a membrane protein aggregate by a chloroplast SRP subunit

    SciTech Connect (OSTI)

    Jaru-Ampornpan, Peera; Shen, Kuang; Lam, Vinh Q.; Ali, Mona; Doniach, Sebastian; Jia, Tony Z.; Shan, Shu-ou (CIT); (Stanford)

    2010-07-23

    Membrane proteins impose enormous challenges to cellular protein homeostasis during their post-translational targeting, and they require chaperones to keep them soluble and translocation competent. Here we show that a novel targeting factor in the chloroplast signal recognition particle (cpSRP), cpSRP43, is a highly specific molecular chaperone that efficiently reverses the aggregation of its substrate proteins. In contrast to 'ATPases associated with various cellular activities' (AAA{sup +}) chaperones, cpSRP43 uses specific binding interactions with its substrate to mediate its 'disaggregase' activity. This disaggregase capability can allow targeting machineries to more effectively capture their protein substrates and emphasizes a close connection between protein folding and trafficking processes. Moreover, cpSRP43 provides the first example to our knowledge of an ATP-independent disaggregase and shows that efficient reversal of protein aggregation can be attained by specific binding interactions between a chaperone and its substrate.

  20. Reversible CO-binding to the Active Site of Nitrogenase | Stanford

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

    Synchrotron Radiation Lightsource Reversible CO-binding to the Active Site of Nitrogenase Tuesday, March 31, 2015 All living organisms depend on the availability of nitrogen for incorporation into the basic biological building blocks such as amino acids and DNA. Globally the largest reservoir for nitrogen is the atmosphere, with an N2 content of roughly 78%. However, as a highly unreactive gas, most organisms are unable to directly utilize dinitrogen due to the severe energy barrier required

  1. Final report for the field-reversed configuration power plant critical-issue scoping study

    SciTech Connect (OSTI)

    Santarius, John F.; Mogahed, Elsayed A.; Emmert, Gilbert A.; Khater, Hesham Y.; Nguyen, Canh N.; Ryzhkov, Sergei V.; Stubna, Michael D.; Steinhauer, Loren C.; Miley, George H.

    2001-03-01

    This report describes research in which a team from the Universities of Wisconsin, Washington, and Illinois performed a scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis of deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core.

  2. Production of field-reversed mirror plasma with a coaxial plasma gun

    DOE Patents [OSTI]

    Hartman, Charles W. (Alamo, CA); Shearer, James W. (Livermore, CA)

    1982-01-01

    The use of a coaxial plasma gun to produce a plasma ring which is directed into a magnetic field so as to form a field-reversed plasma confined in a magnetic mirror. Plasma thus produced may be used as a target for subsequent neutral beam injection or other similarly produced and projected plasma rings or for direct fusion energy release in a pulsed mode.

  3. NEUTRAL BEAM HEATING OF A REVERSED-FIELD PINCH IN THE MADISON

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

    NEUTRAL BEAM HEATING OF A REVERSED-FIELD PINCH IN THE MADISON SYMMETRIC TORUS by Jeff Waksman A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Physics) at the UNIVERSITY OF WISCONSIN-MADISON 2013 Date of final oral examination: June 18, 2013 The dissertation is approved by the following members of the Final Oral Committee: Cary Forest, Professor, Physics Jay Anderson, Associate Scientist, Physics Chris Hegna, Professor, Engineering

  4. Reversible Electrocatalytic Production and Oxidation of Hydrogen at Low Overpotentials by a Functional Hydrogenase Mimic

    SciTech Connect (OSTI)

    Smith, Stuart E.; Yang, Jenny Y.; DuBois, Daniel L.; Bullock, Morris

    2012-03-26

    A new bis(diphosphine) nickel(II) complex, [Ni(PPh2NR2)2](BF4)2, 1, (R = CH2CH2OCH3) is described. A {Delta}G{sup o} of 0.84 kcal/mol{sup -1} for hydrogen addition for this complex was calculated from the experimentally determined equilibrium constant. This complex displays reversible electrocatalytic activity for hydrogen production and oxidation at low overpotentials, a characteristic most commonly associated with hydrogenase enzymes.

  5. Method of electric field flow fractionation wherein the polarity of the electric field is periodically reversed

    DOE Patents [OSTI]

    Stevens, Fred J. (Naperville, IL)

    1992-01-01

    A novel method of electric field flow fractionation for separating solute molecules from a carrier solution is disclosed. The method of the invention utilizes an electric field that is periodically reversed in polarity, in a time-dependent, wave-like manner. The parameters of the waveform, including amplitude, frequency and wave shape may be varied to optimize separation of solute species. The waveform may further include discontinuities to enhance separation.

  6. Damage imaging in a laminated composite plate using an air-coupled time reversal mirror

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

    Le Bas, P. -Y.; Remillieux, M. C.; Pieczonka, L.; Ten Cate, J. A.; Anderson, B. E.; Ulrich, T. J.

    2015-11-03

    We demonstrate the possibility of selectively imaging the features of a barely visible impact damage in a laminated composite plate by using an air-coupled time reversal mirror. The mirror consists of a number of piezoelectric transducers affixed to wedges of power law profiles, which act as unconventional matching layers. The transducers are enclosed in a hollow reverberant cavity with an opening to allow progressive emission of the ultrasonic wave field towards the composite plate. The principle of time reversal is used to focus elastic waves at each point of a scanning grid spanning the surface of the plate, thus allowingmore » localized inspection at each of these points. The proposed device and signal processing removes the need to be in direct contact with the plate and reveals the same features as vibrothermography and more features than a C-scan. More importantly, this device can decouple the features of the defect according to their orientation, by selectively focusing vector components of motion into the object, through air. For instance, a delamination can be imaged in one experiment using out-of-plane focusing, whereas a crack can be imaged in a separate experiment using in-plane focusing. As a result, this capability, inherited from the principle of time reversal, cannot be found in conventional air-coupled transducers.« less

  7. Kinetic simulations of the formation and stability of the field-reversed configuration

    SciTech Connect (OSTI)

    Omelchenko, Yu. A.

    2000-05-01

    The Field-Reversed Configuration (FRC) is a high-beta compact toroidal plasma confined primarily by poloidal fields. In the FRC the external field is reversed on axis by the diamagnetic current carried by thermal plasma particles. A three-dimensional, hybrid, particle-in-cell (zero-inertia fluid electrons, and kinetic ions), code FLAME, previously used to study ion rings [Yu. A. Omelchenko and R. N. Sudan, J. Comp. Phys. 133, 146 (1997)], is applied to investigate FRC formation and tilt instability. Axisymmetric FRC equilibria are obtained by simulating the standard experimental reversed theta-pinch technique. These are used to study the nonlinear tilt mode in the ''kinetic'' and ''fluid-like'' cases characterized by ''small'' ({approx}3) and ''large'' ({approx}12) ratios of the characteristic radial plasma size to the mean ion gyro-radius, respectively. The formation simulations have revealed the presence of a substantial toroidal (azimuthal) magnetic field inside the separatrix, generated due to the stretching of the poloidal field by a sheared toroidal electron flow. This is shown to be an important tilt-stabilizing effect in both cases. On the other hand, the tilt mode stabilization by finite Larmor radius effects has been found relatively insignificant for the chosen equilibria. (c) 2000 American Institute of Physics.

  8. Momentum-independent reflectionless transmission in the non-Hermitian time-reversal symmetric system

    SciTech Connect (OSTI)

    Zhang, X.Z.; Song, Z.

    2013-12-15

    We theoretically study the non-Hermitian systems, the non-Hermiticity of which arises from the unequal hopping amplitude (UHA) dimers. The distinguishing features of these models are that they have full real spectra if all of the eigenvectors are time-reversal (T) symmetric rather than parity-time-reversal (PT) symmetric, and that their Hermitian counterparts are shown to be an experimentally accessible system, which have the same topological structures as that of the original ones but modulated hopping amplitudes within the unbroken region. Under the reflectionless transmission condition, the scattering behavior of momentum-independent reflectionless transmission (RT) can be achieved in the concerned non-Hermitian system. This peculiar feature indicates that, for a certain class of non-Hermitian systems with a balanced combination of the RT dimers, the defects can appear fully invisible to an outside observer. -- Highlights: We investigate the non-Hermitian system with time reversal symmetry. The Hermitian counterpart is experimentally accessible system. The behavior of momentum-independent reflectionless transmission can be achieved. A balanced combination of reflectionless transmission dimers leads to invisibility. It paves an alternative way for the design of invisible cloaking devices.

  9. Statistics of reversible transitions in two-state trajectories in force-ramp spectroscopy

    SciTech Connect (OSTI)

    Diezemann, Gregor

    2014-05-14

    A possible way to extract information about the reversible dissociation of a molecular adhesion bond from force fluctuations observed in force ramp experiments is discussed. For small loading rates the system undergoes a limited number of unbinding and rebinding transitions observable in the so-called force versus extension (FE) curves. The statistics of these transient fluctuations can be utilized to estimate the parameters for the rebinding rate. This is relevant in the experimentally important situation where the direct observation of the reversed FE-curves is hampered, e.g., due to the presence of soft linkers. I generalize the stochastic theory of the kinetics in two-state models to the case of time-dependent kinetic rates and compute the relevant distributions of characteristic forces. While for irreversible systems there is an intrinsic relation between the rupture force distribution and the population of the free-energy well of the bound state, the situation is slightly more complex if reversible systems are considered. For a two-state model, a stationary rupture force distribution that is proportional to the population can be defined and allows to consistently discuss quantities averaged over the transient fluctuations. While irreversible systems are best analyzed in the soft spring limit of small pulling device stiffness and large loading rates, here I argue to use the stiffness of the pulling device as a control parameter in addition to the loading rate.

  10. REVERSIBLE HYDROGEN STORAGE IN A LiBH{sub 4}-C{sub 60} NANOCOMPOSITE

    SciTech Connect (OSTI)

    Teprovich, J.; Zidan, R.; Peters, B.; Wheeler, J.

    2013-08-06

    Reversible hydrogen storage in a LiBH{sub 4}:C{sub 60} nanocomposite (70:30 wt. %) synthesized by solvent-assisted mixing has been demonstrated. During the solvent-assisted mixing and nanocomposite formation, a chemical reaction occurs in which the C{sub 60} cages are significantly modified by polymerization as well as by hydrogenation (fullerane formation) in the presence of LiBH{sub 4}. We have determined that two distinct hydrogen desorption events are observed upon rehydrogenation of the material, which are attributed to the reversible formation of a fullerane (C{sub 60}H{sub x}) as well as a LiBH4 species. This system is unique in that the carbon species (C{sub 60}) actively participates in the hydrogen storage process which differs from the common practice of melt infiltration of high surface area carbon materials with LiBH{sub 4} (nanoconfinment effect). This nanocomposite demonstrated good reversible hydrogen storage properties as well as the ability to absorb hydrogen under mild conditions (pressures as low as 10 bar H{sub 2} or temperatures as low as 150?C). The nanocomposite was characterized by TGA-RGA, DSC, XRD, LDI-TOF-MS, FTIR, 1H NMR, and APPI MS.

  11. Damage imaging in a laminated composite plate using an air-coupled time reversal mirror

    SciTech Connect (OSTI)

    Le Bas, P. -Y.; Remillieux, M. C.; Pieczonka, L.; Ten Cate, J. A.; Anderson, B. E.; Ulrich, T. J.

    2015-11-03

    We demonstrate the possibility of selectively imaging the features of a barely visible impact damage in a laminated composite plate by using an air-coupled time reversal mirror. The mirror consists of a number of piezoelectric transducers affixed to wedges of power law profiles, which act as unconventional matching layers. The transducers are enclosed in a hollow reverberant cavity with an opening to allow progressive emission of the ultrasonic wave field towards the composite plate. The principle of time reversal is used to focus elastic waves at each point of a scanning grid spanning the surface of the plate, thus allowing localized inspection at each of these points. The proposed device and signal processing removes the need to be in direct contact with the plate and reveals the same features as vibrothermography and more features than a C-scan. More importantly, this device can decouple the features of the defect according to their orientation, by selectively focusing vector components of motion into the object, through air. For instance, a delamination can be imaged in one experiment using out-of-plane focusing, whereas a crack can be imaged in a separate experiment using in-plane focusing. As a result, this capability, inherited from the principle of time reversal, cannot be found in conventional air-coupled transducers.

  12. Location of gap nodes in the organic superconductors {kappa}-(ET){sub 2}Cu(NCS){sub 2} and {kappa}-(ET){sub 2}Cu[N(CN){sub 2}Br determined by magnetocalorimetry.

    SciTech Connect (OSTI)

    Malone, L.; Taylor, O. J.; Schlueter, J. A.; Carrington, A.; Materials Science Division; Univ. Bristol

    2010-07-16

    We report specific-heat measurements of the organic superconductors {kappa}-(ET){sub 2}Cu(NCS){sub 2} and {kappa}-(ET){sub 2}Cu[N(CN){sub 2}]Br. When the magnetic field is rotated in the highly conducting planes at low temperature (T = 0.4 K), we observe clear oscillations of specific heat which have a strong fourfold component. The observed strong field and temperature dependence of this fourfold component identifies it as originating from nodes in the superconducting energy gap which point along the in-plane crystal axes (d{sub xy} symmetry).

  13. Atomic-scale observation of parallel development of super elasticity and reversible plasticity in GaAs nanowires

    SciTech Connect (OSTI)

    Bao, Peite; Du, Sichao; Zheng, Rongkun; Wang, Yanbo; Liao, Xiaozhou; Cui, Xiangyuan; Yen, Hung-Wei; Kong Yeoh, Wai; Ringer, Simon P.; Gao, Qiang; Hoe Tan, H.; Jagadish, Chennupati; Liu, Hongwei; Zou, Jin

    2014-01-13

    We report the atomic-scale observation of parallel development of super elasticity and reversible dislocation-based plasticity from an early stage of bending deformation until fracture in GaAs nanowires. While this phenomenon is in sharp contrast to the textbook knowledge, it is expected to occur widely in nanostructures. This work indicates that the super recoverable deformation in nanomaterials is not simple elastic or reversible plastic deformation in nature, but the coupling of both.

  14. Depth profile of a time-reversal focus in an elastic solid

    SciTech Connect (OSTI)

    Remillieux, Marcel C.; Anderson, Brian E.; Ulrich, T. J.; Le Bas, Pierre -Yves; Payan, Cedric

    2015-04-01

    The out-of-plane velocity component is focused on the flat surface of an isotropic solid sample using the principle of time reversal. This experiment is often reproduced in the context of nondestructive testing for imaging features near the surface of the sample. However, it is not clear how deep the focus extends into the bulk of the sample and what its profile is. In this paper, this question is answered using both numerical simulations and experimental data. The profiles of the foci are expressed in terms of the wavelengths of the dominant waves, based on the interpretation of the Lambs problem and the use of the diffraction limit.

  15. Numerical studies of active current profile control in the reversed-field pinch

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

    studies of active current profile control in the reversed-field pinch This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2007 Plasma Phys. Control. Fusion 49 183 (http://iopscience.iop.org/0741-3335/49/2/008) Download details: IP Address: 128.104.166.214 The article was downloaded on 13/10/2010 at 22:13 Please note that terms and conditions apply. View the table of contents for this issue, or go to the journal homepage for more Home Search

  16. Off-axis sawteeth and double-tearing reconnection in reversed magnetic shear plasmas in TFTR

    SciTech Connect (OSTI)

    Chang, Z.; Park, W.; Fredrickson, E.D.

    1996-06-01

    Off-axis sawteeth are often observed in reversed magnetic shear plasmas when the minimum safety factor q is near or below 2. Fluctuations with m/n = 2/1 (m and n are the poloidal and toroidal mode numbers) appear before and after the crashes. Detailed comparison has been made between the measured T{sub e} profile evolution during the crash and a nonlinear numerical magnetohydrodynamics (MHD) simulation. The good agreement between the observation and simulation indicates that the off-axis sawteeth are due to a double-tearing magnetic reconnection process.

  17. Generation and confinement of hot ions and electrons in a reversed-field pinch plasma

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

    Generation and confinement of hot ions and electrons in a reversed-field pinch plasma This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2010 Plasma Phys. Control. Fusion 52 124048 (http://iopscience.iop.org/0741-3335/52/12/124048) Download details: IP Address: 128.104.166.218 The article was downloaded on 15/04/2013 at 17:21 Please note that terms and conditions apply. View the table of contents for this issue, or go to the journal homepage for

  18. Global confinement and discrete dynamo activity in the MST reversed-field pinch

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

    confinement and discrete dynamo activity in the MST reversed-field pinch* S. Hokin,+ A. Almagri, S. Assadi, J. Beckstead, G. Chartas, N. Cracker, M. Cudzinovic, D. Den Hat-tog, FL Dexter, D. Holly, S. Prager, T. Rempel, J. Sarff, E. Scime, W. Shen, C. Spragins, C. Sprott, G. Starr, M. Stoneking, and C. Watts University of Wisconsin, Madison, Wisconsin 53 706 R. Nebel Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (Received 10 December 1990; accepted 1 April 199 1) Results obtained

  19. Electromagnetic drift instabilities in high-beta plasma under conditions of a field reversed configuration

    SciTech Connect (OSTI)

    Chirkov, A. Yu.; Khvesyuk, V. I.

    2010-01-15

    Electromagnetic drift instabilities are studied in the conditions of a field reversed configuration (FRC). Dispersion equation is based on the set of Vlasov-Maxwell equations taking into account nonadiabatic responses both of ions and electrons. Considered drift instabilities are caused by density and temperature gradients. It is assumed that magnetic field of the FRC is purely poloidal. Two kinds of magnetic field nonuniformity are considered: (i) perpendicular gradient due to high beta values (beta is the plasma pressure/magnetic pressure) and (ii) curvature of magnetic lines. There is low frequency drift instability existing for high-beta regimes. Modes of such instability can propagate transversally to the unperturbed magnetic field lines.

  20. Enhanced Confinement and Stability of a Field-Reversed Configuration with Rotating Magnetic Field Current Drive

    SciTech Connect (OSTI)

    Slough, J. T.; Miller, K. E.

    2000-08-14

    A new experiment has been constructed to study the sustainment of a field-reversed configuration (FRC) with a rotating magnetic field (RMF). FRCs were formed with cold, unmagnetized ions and thus without a kinetic ion component that was believed to provide stability to internal tilt modes. No destructive instabilities were observed for the RMF FRC. Only peripheral radial penetration of the RMF was observed. The radially inward flow arising from axial screening currents at the FRC edge reduced convective and conductive losses to the measurement limit of the diagnostics. (c) 2000 The American Physical Society.

  1. Tearing relaxation and the globalization of transport in field-reversed configurations

    SciTech Connect (OSTI)

    Steinhauer, Loren; Barnes, D. C.

    2009-09-15

    Tearing instability of field-reversed configurations (FRC) is investigated using the method of neighboring equilibria. It is shown that the conducting wall position in experiment lies very close to the location needed for tearing stability. This strongly suggests that vigorous but benign tearing modes, acting globally, are the engine of continual self-organization in FRCs, i.e., tearing relaxation. It also explains the ''profile consistency'' and anomalous loss rate of magnetic flux. In effect, tearing globalizes the effect of edge-driven transport.

  2. Separatrix radius measurement of field-reversed configuration plasma in FRX-L

    SciTech Connect (OSTI)

    Zhang, S.Y.; Tejero, E.M.; Taccetti, J.M.; Wurden, G.A.; Intrator, T.P.; Waganaar, W.J.; Perkins, R.

    2004-10-01

    Magnetic pickup coils and single turn flux loops are installed on the FRX-L device. The combination of the two measurements provides the excluded flux radius that approximates the separatrix radius of the field-reversed configuration (FRC) plasma. Arrays of similar probes are used to map out local magnetic field dynamics beyond both ends of the theta-coil confinement region to help understand the effects of cusp locations on flux trapping during the FRC formation process. Details on the probe design and system calibrations are presented. The overall system calibration of excluded flux radius measurement is examined by replacing FRC plasma with a known radius aluminum conductor cylinder.

  3. An Enhanced Nonlinear Critical Gradient for Electron Turbulent Transport due to Reversed Magnetic Shear

    SciTech Connect (OSTI)

    Peterson, J. L.; Hammet, G. W.; Mikkelsen, D. R.; Yuh, H. Y.; Candy, J.; Guttenfelder, W.; Kaye, S. M.; LeBlanc, B.

    2011-05-11

    The first nonlinear gyrokinetic simulations of electron internal transport barriers (e-ITBs) in the National Spherical Torus Experiment show that reversed magnetic shear can suppress thermal transport by increasing the nonlinear critical gradient for electron-temperature-gradient-driven turbulence to three times its linear critical value. An interesting feature of this turbulence is non- linearly driven off-midplane radial streamers. This work reinforces the experimental observation that magnetic shear is likely an effective way of triggering and sustaining e-ITBs in magnetic fusion devices.

  4. Watermelon-like iron nanoparticles: Cr doping effect on magnetism and magnetization interaction reversal

    SciTech Connect (OSTI)

    Kaur, Maninder; Dai, Qilin; Bowden, Mark E.; Engelhard, Mark H.; Wu, Yaqiao; Tang, Jinke; Qiang, You

    2013-06-26

    Chromium (Cr) forms a solid solution with iron (Fe) lattice when doped in core-shell iron -iron oxide nanocluster (NC) and shows a mixed phase of sigma (?) FeCr and bcc Fe. The Cr dopant affects heavily the magnetization and magnetic reversal process, and causes the hysteresis loop to shrink near the zero field axis. Dramatic transformation happens from dipolar interaction (0 at. % Cr) to strong exchange interaction (8 at. % of Cr) is confirmed from the Henkel plot and delta M plot, and is explained by a water-melon model of core-shell NC system.

  5. Formation, spin-up, and stability of field-reversed configurations

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

    Omelchenko, Yuri A.

    2015-08-24

    Formation, spontaneous spin-up and stability of theta-pinch formed field-reversed configurations are studied self-consistently in three dimensions with a multiscale hybrid model that treats all plasma ions as full-orbit collisional macro-particles and the electrons as a massless quasineutral fluid. The end-to-end hybrid simulations for the first time reveal poloidal profiles of implosion-driven fast toroidal plasma rotation and demonstrate three well-known discharge regimes as a function of experimental parameters: the decaying stable configuration, the tilt unstable configuration and the nonlinear evolution of a fast growing tearing mode.

  6. Reversible CO Binding Enables Tunable CO/H2 and CO/N2 Separations in

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

    Metal-Organic Frameworks with Exposed Divalent Metal Cations | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Reversible CO Binding Enables Tunable CO/H2 and CO/N2 Separations in Metal-Organic Frameworks with Exposed Divalent Metal Cations Previous Next List Eric D. Bloch, Matthew R. Hudson, Jarad A. Mason, Sachin Chavan, Valentina Crocellà, Joshua D. Howe, Kyuho Lee, Allison L. Dzubak, Wendy L. Queen, Joseph M. Zadrozny, Stephen J. Geier, Li-Chiang Lin,

  7. Strong and Reversible Binding of Carbon Dioxide in a Green Metal-Organic

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

    Framework | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Strong and Reversible Binding of Carbon Dioxide in a Green Metal-Organic Framework Previous Next List Jeremiah J. Gassensmith, Hiroyasu Furukawa, Ronald A. Smaldone, Ross S. Forgan, Youssry Y. Botros, Omar M. Yaghi, and J. Fraser Stoddart, J. Am. Chem. Soc., 2011, 133 (39), pp 15312-15315 DOI: 10.1021/ja206525x Abstract Image Abstract: The efficient capture and storage of gaseous CO2 is a pressing

  8. Polarization reversal and domain kinetics in magnesium doped stoichiometric lithium tantalate

    SciTech Connect (OSTI)

    Shur, V. Ya., E-mail: vladimir.shur@urfu.ru; Akhmatkhanov, A. R.; Baturin, I. S. [Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation); Labfer Ltd., 620014 Ekaterinburg (Russian Federation); Chuvakova, M. A. [Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation)

    2014-10-13

    The polarization reversal process has been studied in 1?mol.?% MgO doped stoichiometric lithium tantalate (LT) single crystal. The revealed stages of domain structure evolution represent (1) continuous nucleation and growth of isolated hexagonal domains with walls oriented along Y directions and (2) continuous motion of the plane domain walls stimulated by merging with isolated domains. The activation field dependence of the switching time has been revealed. The coercive field for quasi-static switching is about 150?V/mm. The bulk screening process has been analyzed. The main parameters of the switching process have been compared with other representatives of LT family.

  9. Numerical analysis of thermally assisted spin-transfer torque magnetization reversal in synthetic ferrimagnetic free layers

    SciTech Connect (OSTI)

    Shen, J.; Shi, M.; Tanaka, T. Matsuyama, K.

    2015-05-07

    The spin transfer torque magnetization reversal of synthetic ferrimagnetic free layers under pulsed temperature rise was numerically studied by solving the LandauLifshitzGilbert equation, taking into account the stochastic random fields, the temperature dependence of magnetic parameters, and the spin torque terms. The anti-parallel magnetization configuration was retained at the elevated temperature, due to interlayer dipole coupling. A significant thermal assistance effect, resulting in a 40% reduction in the switching current, was demonstrated during a nanosecond pulsed temperature rise up to 77% of the Curie temperature.

  10. Effect of externally applied pressure on the magnetic behavior of Cu{sub 2}Te{sub 2}O{sub 5}(Br{sub x}Cl{sub 1-x}){sub 2}

    SciTech Connect (OSTI)

    Crowe, S. J.; Lees, M. R.; Paul, D. M. K.; Bewely, R. I.; Taylor, J.; McIntyre, G.; Zaharko, O.; Berger, H.

    2006-04-01

    The effect of externally applied pressure on the magnetic behavior of Cu{sub 2}Te{sub 2}O{sub 5}(Br{sub x}Cl{sub 1-x}){sub 2} with x=0, 0.73, and 1, is investigated by a combination of magnetic susceptibility, neutron diffraction, and neutron inelastic scattering measurements. The magnetic transition temperatures of the x=0 and 0.73 compositions are observed to increase linearly with increasing pressure at a rate of 0.23(2) and 0.04(1) K/kbar, respectively. However, the bromide shows contrasting behavior with a large suppression of the transition temperature under pressure, at a rate of -0.95(9) K/kbar. In neutron inelastic scattering measurements of Cu{sub 2}Te{sub 2}O{sub 5}Br{sub 2} under pressure only a small change to the ambient pressure magnetic excitations were observed. A peak in the density of states was seen to shift from {approx}5 meV in ambient pressure to {approx}6 meV under an applied pressure of 11.3 kbar, which was associated with an increase in the overall magnetic coupling strength.

  11. Spectral indices measurements using miniature fission chambers at the MINERVE zero-power reactor at CEA using calibration data obtained at the BR1 reactor at SCK.CEN

    SciTech Connect (OSTI)

    De lanaute, N. Blanc; Mellier, F.; Lyoussi, A.; Domergue, C.; Di Salvo, J. [CEA, DEN, DER, SPEX, F-13108 St Paul Les Durance, (France); Borms, L.; Wagemans, J. [CEN SCK, Belgian Nucl Res Ctr, B-2400 Mol, (Belgium)

    2012-08-15

    Spectral indices measurements performed in 2004 at the CEA MINERVE facility loaded with the R-UO{sub 2} lattice, using calibration data acquired at the SCK center dot CEN BR1 facility in 2001, resulted in ambivalent conclusions. On one hand, spectral indices involving only fissile isotopes gave consistent discrepancies between calculation and experiment. On the other hand, spectral indices involving both fissile and fertile isotopes, in particular the {sup 238}U(n, f)/{sup 235}U(n, f) spectral index, showed inconsistent results depending on the type of calibration data used. For different reasons, no definitive explanation was given at that time. In 2009, the preparation of the AMMON program at the EOLE facility motivated the manufacturing of a new set of detectors. At the same time, the re-installation of the R1-UO{sub 2} lattice in MINERVE provided the opportunity to carry out again a spectral indices measurement campaign. Nevertheless, although the isotopic compositions of active deposits were better known than previously, the comparison between experimental results and calculations still lead to inconsistent discrepancies. In April 2010, a new calibration series conducted again at the BR1 facility allowed the CEA to reanalyze the spectral indices measurements performed in 2009. With these very latest calibration data, experimental values of spectral indices finally matched calculations within the uncertainty margins. This paper also sums up the work that has been achieved to explain the incoherencies observed in 2004. (authors)

  12. Imaging Faults with Reverse-Time Migration for Geothermal Exploration at Jemez Pueblo in New Mexico

    SciTech Connect (OSTI)

    Huang, Lianjie; Albrecht, Michael; Kaufman, Greg; Kelley, Shari; Rehfeldt, Kenneth; Zhang, Zhifu

    2011-01-01

    The fault zones at Jemez Pueblo may dominate the flow paths of hot water, or confine the boundaries of the geothermal reservoir. Therefore, it is crucial to image the geometry of these fault zones for geothermal exploration in the area. We use reverse-time migration with a separation imaging condition to image the faults at Jemez Pueblo. A finite-difference full-wave equation method with a perfectly-matching-layer absorbing boundary condition is used for backward propagation of seismic reflection data from receivers and forward propagation of wavefields from sources. In the imaging region, the wavefields are separated into the upgoing and downgoing waves, and leftgoing and rightgoing waves. The upgoing and downgoing waves are used to obtain the downward-looking image, and the leftgoing and rightgoing waves are used to form the left-looking image and right-looking image from sources. The left-looking and right-looking images are normally weaker than the downward-looking image because the reflections from the fault zones are much weaker than those from sedimentary layers, but these migration results contain the images of the faults. We apply our reverse-time migration with a wavefield separation imaging condition to seismic data acquired at Jemez Pueblo, and our preliminary results reveal many faults in the area.

  13. Deuterium-Tritium Simulations of the Enhanced Reversed Shear Mode in the Tokamak Fusion Test Reactor

    SciTech Connect (OSTI)

    Mikkelsen, D.R.; Manickam, J.; Scott, S.D.; Zarnstorff

    1997-04-01

    The potential performance, in deuterium-tritium plasmas, of a new enhanced con nement regime with reversed magnetic shear (ERS mode) is assessed. The equilibrium conditions for an ERS mode plasma are estimated by solving the plasma transport equations using the thermal and particle dif- fusivities measured in a short duration ERS mode discharge in the Tokamak Fusion Test Reactor [F. M. Levinton, et al., Phys. Rev. Letters, 75, 4417, (1995)]. The plasma performance depends strongly on Zeff and neutral beam penetration to the core. The steady state projections typically have a central electron density of {approx}2:5x10 20 m{sup -3} and nearly equal central electron and ion temperatures of {approx}10 keV. In time dependent simulations the peak fusion power, {approx} 25 MW, is twice the steady state level. Peak performance occurs during the density rise when the central ion temperature is close to the optimal value of {approx} 15 keV. The simulated pressure profiles can be stable to ideal MHD instabilities with toroidal mode number n = 1, 2, 3, 4 and {infinity} for {beta}{sub norm} up to 2.5; the simulations have {beta}{sub norm} {le} 2.1. The enhanced reversed shear mode may thus provide an opportunity to conduct alpha physics experiments in conditions imilar to those proposed for advanced tokamak reactors.

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

    SciTech Connect (OSTI)

    2011-12-05

    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 nightwhen the sun is not outto 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. PNNLs 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- 800C). A high-temperature tank in PNNLs 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 PNNLs thermal energy storage system is expected to keep costs down. The system has the potential to significantly increase energy density.

  15. Experimental profile evolution of a high-density field-reversed configuration

    SciTech Connect (OSTI)

    Ruden, E. L.; Zhang, Shouyin; Intrator, T. P.; Wurden, G. A.

    2006-12-15

    A field-reversed configuration (FRC) gains angular momentum over time, eventually resulting in an n=2 rotational instability (invariant under rotation by {pi}) terminating confinement. To study this, a laser interferometer probes the time history of line integrated plasma density along eight chords of the high-density ({approx}10{sup 17} cm{sup -3}) field-reversed configuration experiment with a liner. Abel and tomographic inversions provide density profiles during the FRC's azimuthally symmetric phase, and over a period when the rotational mode has saturated and rotates with a roughly fixed profile, respectively. During the latter part of the symmetric phase, the FRC approximates a magnetohydrodynamic (MHD) equilibrium, allowing the axial magnetic-field profile to be calculated from pressure balance. Basic FRC properties such as temperature and poloidal flux are then inferred. The subsequent two-dimensional n=2 density profiles provide angular momentum information needed to set bounds on prior values of the stability relevant parameter {alpha} (rotational to ion diamagnetic drift frequency ratio), in addition to a view of plasma kinematics useful for benchmarking plasma models of higher order than MHD.

  16. Nonlinear stability of field-reversed configurations with self-generated toroidal field

    SciTech Connect (OSTI)

    Omelchenko, Y. A.; Schaffer, M. J.; Parks, P. B.

    2001-10-01

    The field-reversed configuration (FRC) is a high-beta compact toroidal plasma confinement scheme in which the external poloidal field is reversed on the geometric axis by azimuthal (toroidal) plasma current. A quasineutral, hybrid, particle-in-cell (PIC) approach [Y. A. Omelchenko and R. N. Sudan, Phys. Plasmas 2, 2773 (1995)] is applied to study long-term nonlinear stability of computational FRC equilibria to a number of toroidal modes, including the most disruptive tilt mode. In particular, a self-generated toroidal magnetic field is found to be an important factor in mitigating the instability and preventing the confinement disruption. This is shown to be a unique FRC property resulting from the Hall effect in the regions of vanishing poloidal magnetic field. The instability-driven toroidal field stabilizes kink formation by increasing the magnetic field energy without destabilizing curvature-driven plasma motion. Finally, the tilt instability saturates due to nonlinear, finite Larmor radius (FLR) effects and plasma relaxation to a quasisteady kinetic state. During this transition the FRC is shown to dissipate a substantial amount of initially trapped flux and plasma energy. These effects are demonstrated for kinetic and fluid-like, spherical and prolate FRCs.

  17. Nonlinear electron magnetohydrodynamics physics. I. Whistler spheromaks, mirrors, and field reversed configurations

    SciTech Connect (OSTI)

    Stenzel, R. L.; Urrutia, J. M.; Strohmaier, K. D.

    2008-04-15

    The nonlinear interactions of time-varying magnetic fields with plasmas is investigated in the regime of electron magnetohydrodynamics. Simple magnetic field geometries are excited in a large laboratory plasma with a loop antenna driven with large oscillatory currents. When the axial loop field opposes the ambient field, the net field can be reversed to create a field-reversed configuration (FRC). In the opposite polarity, a strong field enhancement is produced. The time-varying antenna field excites whistler modes with wave magnetic fields exceeding the ambient magnetic field. The resulting magnetic field topologies have been measured. As the magnetic topology is changed from FRC to strong enhancement, two propagating field configurations resembling spheromaks are excited, one with positive and the other with negative helicity. Such 'whistler spheromaks' propagate with their null points along the weaker ambient magnetic field, with the current density localized around its O-line. In contrast, 'whistler mirrors' which have topologies similar to linear whistlers, except with B{sub wave}>B{sub 0}, have no null regions and, therefore, broad current layers. This paper describes the basic field topologies of whistler spheromaks and mirrors, while companion papers discuss the associated nonlinear phenomena as well as the interaction between them.

  18. Reversible Ionic Liquids as Double-Action Solvents for Efficient CO2 Capture

    SciTech Connect (OSTI)

    Eckert, Charles; Liotta, Charles

    2011-09-30

    We have developed a novel class of CO{sub 2} capture solvents, Reversible Ionic Liquids (RevILs), that offer high absorption capacity through two modes of capture: chemical reaction (chemisorption) and physical solubility (physisorption). These solvents are silicon containing alkaline compounds such as silylamines that form a liquid salt (ionic liquid) upon reaction with CO{sub 2}. Subsequently, modest elevations in temperature reverse the reaction and yield pure CO{sub 2} for sequestration. By incorporating Si in the molecules we have reduced the viscosity, thereby improving the mass transfer rates of CO{sub 2} absorption/desorption and decreasing the processing costs for pumping the solvent. In this project, we have made systematic changes to the structure of these compounds to improve several physical and thermodynamic properties important for CO{sub 2} capture. Through these structure-property paradigms, we have obtained a RevIL which requires only a third of the energy required by conventional aqueous MEA process for 90% CO{sub 2} capture.

  19. Reversible Ionic Liquids as Double-Action Solvents for Efficient CO{sub 2} Capture

    SciTech Connect (OSTI)

    Charles Eckert; Charles Liotta

    2011-09-30

    We have developed a novel class of CO{sub 2} capture solvents, Reversible Ionic Liquids (RevILs), that offer high absorption capacity through two modes of capture: chemical reaction (chemisorption) and physical solubility (physisorption). These solvents are silicon containing alkaline compounds such as silylamines that form a liquid salt (ionic liquid) upon reaction with CO{sub 2}. Subsequently, modest elevations in temperature reverse the reaction and yield pure CO{sub 2} for sequestration. By incorporating Si in the molecules we have reduced the viscosity, thereby improving the mass transfer rates of CO{sub 2} absorption/desorption and decreasing the processing costs for pumping the solvent. In this project, we have made systematic changes to the structure of these compounds to improve several physical and thermodynamic properties important for CO{sub 2} capture. Through these structure-property paradigms, we have obtained a RevIL which requires only a third of the energy required by conventional aqueous MEA process for 90% CO{sub 2} capture.

  20. Metalized T graphene: A reversible hydrogen storage material at room temperature

    SciTech Connect (OSTI)

    Ye, Xiao-Juan; Zhong, Wei, E-mail: csliu@njupt.edu.cn, E-mail: wzhong@nju.edu.cn; Du, You-Wei [Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China); Liu, Chun-Sheng, E-mail: csliu@njupt.edu.cn, E-mail: wzhong@nju.edu.cn [Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023 (China); Zeng, Zhi [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2014-09-21

    Lithium (Li)-decorated graphene is a promising hydrogen storage medium due to its high capacity. However, homogeneous mono-layer coating graphene with lithium atoms is metastable and the lithium atoms would cluster on the surface, resulting in the poor reversibility. Using van der Waals-corrected density functional theory, we demonstrated that lithium atoms can be homogeneously dispersed on T graphene due to a nonuniform charge distribution in T graphene and strong hybridizations between the C-2p and Li-2p orbitals. Thus, Li atoms are not likely to form clusters, indicating a good reversible hydrogen storage. Both the polarization mechanism and the orbital hybridizations contribute to the adsorption of hydrogen molecules (storage capacity of 7.7 wt. %) with an optimal adsorption energy of 0.19 eV/H?. The adsorption/desorption of H? at ambient temperature and pressure is also discussed. Our results can serve as a guide in the design of new hydrogen storage materials based on non-hexagonal graphenes.

  1. Fine particle (2.5 microns) emissions: regulations, measurement, and control

    SciTech Connect (OSTI)

    John D. McKenna; James H. Turner; James P. McKenna, Jr.

    2008-09-15

    Contents: Introduction; Health effects; Air monitoring; Emission control methods - fabric filter/baghouses, electrostatic precipitators, wet scrubbers; Environmental technology verification and baghouse filtration products; Cost considerations; and Nanoparticulates.

  2. Solid-state synthesis, structure and properties of a novel open-framework cadmium selenite bromide: [Cd{sub 10}(SeO{sub 3}){sub 8}Br{sub 4}]·HBr·H{sub 2}O

    SciTech Connect (OSTI)

    Chen, Wen-Tong; Wang, Ming-Sheng; Wang, Guan-E; Chen, Hui-Fen; Guo, Guo-Cong

    2013-08-15

    A novel open-framework cadmium selenite bromide, [Cd{sub 10}(SeO{sub 3}){sub 8}Br{sub 4}]·HBr·H{sub 2}O (1), has been obtained by a solid-state reaction at 450 °C, and the structure has been determined by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in Pbcm of the orthorhombic system: a=10.882(3), b=16.275(5), c=18.728(6) Å, V=3317(2) Å{sup 3}, R1/wR2=0.0411/0.0659. Compound 1 is characteristic of a novel 3-D open-framework structure, composing {sub ∞}{sup 2}[CdSeO{sub 3}] layers and the pillars of edge-shared CdO{sub 3}Br{sub 2} square pyramids. The lattice water molecules and the HBr molecules locate in the voids of the framework. Optical absorption spectrum of 1 reveals the presence of an optical gap of 1.65 eV. Solid-state photoluminescent study indicates that compound 1 exhibits strong violet emission. TG–DSC measurement shows that compound 1 is thermally stable up to 200 °C. - Graphical abstract: A metal selenite halide has been synthesized and features a 3-D open-framework structure, composing edge-shared CdO{sub 8} decahedra and pillars of edge-sharing pentahedra. UV–vis, TG–DSC and luminescent measurements are also reported. Highlights: • This paper reports a novel cadmium selenite bromide obtained by an intermediate-temperature solid-state reaction. • The title compound is characteristic of a novel 3-D open-framework structure, composing {sub ∞}{sup 2}[CdSeO{sub 3}] layers and the pillars of edge-shared CdO{sub 3}Br{sub 2} square pyramids. • The title compound is thermally stable up to 200 °C. • The title compound has an optical gap of 1.65 eV and exhibits strong violet emission.

  3. Resin-assisted enrichment of thiols as a general strategy for proteomic profiling of cysteine-based reversible modifications

    SciTech Connect (OSTI)

    Guo, Jia; Gaffrey, Matthew J.; Su, Dian; Liu, Tao; Camp, David G.; Smith, Richard D.; Qian, Weijun

    2013-12-12

    Reversible modifications on cysteine thiols play a significant role in redox signaling and regulation. A number of reversible redox modifications, including disulfide formation, S-nitrosylation, and S-glutathionylation, have been recognized for their significance in various physiological and pathological processes. Here we describe in detail a resin-assisted thiol-affinity enrichment protocol for both biochemical and proteomics applications. This protocol serves as a general approach for specific isolation of thiol-containing proteins or peptides derived from reversible redox-modified proteins. This approach utilizes thiol-affinity resins to directly capture thiol-containing proteins or peptides through a disulfide exchange reaction followed by on-resin protein digestion and on-resin multiplexed isobaric labeling to facilitate LC-MS/MS based quantitative site-specific analysis of redox modifications. The overall approach requires a much simpler workflow with increased specificity compared to the commonly used biotin switch technique. By coupling different selective reduction strategies, the resin-assisted approach provides the researcher with a useful tool capable of enriching different types of reversible modifications on protein thiols. Procedures for selective enrichment and analyses of S-nitrosylation and total reversible cysteine oxidation are presented to demonstrate the utility of this general strategy.

  4. System and method for manipulating domain pinning and reversal in ferromagnetic materials

    DOE Patents [OSTI]

    Silevitch, Daniel M.; Rosenbaum, Thomas F.; Aeppli, Gabriel

    2013-10-15

    A method for manipulating domain pinning and reversal in a ferromagnetic material comprises applying an external magnetic field to a uniaxial ferromagnetic material comprising a plurality of magnetic domains, where each domain has an easy axis oriented along a predetermined direction. The external magnetic field is applied transverse to the predetermined direction and at a predetermined temperature. The strength of the magnetic field is varied at the predetermined temperature, thereby isothermally regulating pinning of the domains. A magnetic storage device for controlling domain dynamics includes a magnetic hard disk comprising a uniaxial ferromagnetic material, a magnetic recording head including a first magnet, and a second magnet. The ferromagnetic material includes a plurality of magnetic domains each having an easy axis oriented along a predetermined direction. The second magnet is positioned adjacent to the magnetic hard disk and is configured to apply a magnetic field transverse to the predetermined direction.

  5. Time-reversal symmetry breaking and the field theory of quantum chaos

    SciTech Connect (OSTI)

    Simons, B.D. [Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE (United Kingdom)] [Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE (United Kingdom); Agam, O. [NEC Research Institute, 4 Independence Way, Princeton, New Jersey 08540 (United States)] [NEC Research Institute, 4 Independence Way, Princeton, New Jersey 08540 (United States); Andreev, A.V. [Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States)] [Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States)

    1997-04-01

    Recent studies have shown that the quantum statistical properties of systems which are chaotic in their classical limit can be expressed in terms of an effective field theory. Within this description, spectral properties are determined by low energy relaxation modes of the classical evolution operator. It is in the interaction of these modes that quantum interference effects are encoded. In this paper we review this general approach and discuss how the theory is modified to account for time-reversal symmetry breaking. To keep our discussion general, we will also briefly describe how the theory is modified by the presence of an additional discrete symmetry such as inversion. Throughout, parallels are drawn between quantum chaotic systems and the properties of weakly disordered conductors. {copyright} {ital 1997 American Institute of Physics.}

  6. Symmetries and quantum chaos: Time-reversal invariance in the nucleon-nucleon interaction

    SciTech Connect (OSTI)

    French, J.B.; Kota, V.K.B.; Pandey, A.; Tomsovic, S.

    1987-06-08

    Let ..cap alpha.. be the relative norm of a symmetry-breaking term in the Hamiltonian of a many-particle system, and ..lambda.. the energy-dependent transition parameter which charcterizes the quantum chaos via spectral and strength fluctuations. Combining a compact theory for ..lambda../..cap alpha../sup 2/ with fluctuation theories by which ..lambda.. can be deduced from (neutron-resonance) data gives, for the time-reversal-noninvariant nucleon-nucleon interaction, ..cap alpha..less than or equal to(1--2) x 10/sup -3/, which would improve with better small-strength data in nuclei with dense spectra. Diffusion equations involving ..lambda.. as the ''time'' variable are also discussed.

  7. Effect of Ion Skin Depth on Relaxation of Merging Spheromaks to a Field-Reversed Configuration

    SciTech Connect (OSTI)

    Kawamori, Eiichirou; Ono, Yasushi

    2005-08-19

    The effect of ion skin depth on the relaxation of merging spheromaks to a field-reversed configuration (FRC) is studied experimentally for a wide range of size parameter S* (ratio of minor radius to ion skin depth) from 1 to 7. The two merging spheromaks are observed to relax to an FRC or a new spheromak depending on whether the initial poloidal eigenvalue is smaller or larger than a threshold value. The bifurcation value is found to increase with decreasing size parameter S{sup *}, indicating that the low-S* condition provides a wide bifurcated range of relaxation to an FRC. The FRC-style relaxation under the low-S* conditions was accompanied by the suppression of the low-n modes (n is the toroidal mode number) activity. The fast rotations of the modes were followed by suppression of the low-n modes.

  8. Field-Reversed Configuration Formation Scheme Utilizing a Spheromak and Solenoid Induction

    SciTech Connect (OSTI)

    Gerhardt, S. P.; Belova, E. V.; Yamada, M.; Ji, H.; Ren, B.; McGeehan, B.; Inomoto, M.

    2008-06-12

    A new field-reversed configuration (FRC) formation technique is described, where a spheromak transitions to a FRC with inductive current drive. The transition is accomplished only in argon and krypton plasmas, where low-n kink modes are suppressed; spheromaks with a lighter majority species, such as neon and helium, either display a terminal tilt-mode, or an n=2 kink instability, both resulting in discharge termination. The stability of argon and krypton plasmas through the transition is attributed to the rapid magnetic diffusion of the currents that drive the kink-instability. The decay of helicity during the transition is consistent with that expected from resistivity. This observation indicates a new scheme to form a FRC plasma, provided stability to low-n modes is maintained, as well as a unique situation where the FRC is a preferred state.

  9. Field-Reversed Configuration Power Plant Critical-Issue Scoping Study

    SciTech Connect (OSTI)

    Santarius, J. F.; Mogahed, E. A.; Emmert, G. A.; Khater, H. Y.; Nguyen, C. N.; Ryzhkov, S. V.; Stubna, M. D.

    2000-03-31

    A team from the Universities of Wisconsin, Washington, and Illinois performed an engineering scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis for deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core. For the engineering conceptual design of the fusion core, the project team focused on intermediate-term technology. For example, one decision was to use steele structure. The FRC systems analysis led to a fusion power plant with attractive features including modest size, cylindrical symmetry, good thermal efficiency (52%), relatively easy maintenance, and a high ratio of electric power to fusion core mass, indicating that it would have favorable economics.

  10. Formation of a field reversed configuration for magnetic and electrostatic confinement of plasma

    DOE Patents [OSTI]

    Rostoker, Norman; Binderbauer, Michl; Qerushi, Artan; Tahsiri, Hooshang

    2007-02-20

    A system and method for containing plasma and forming a Field Reversed Configuration (FRC) magnetic topology are described in which plasma ions are contained magnetically in stable, non-adiabatic orbits in the FRC. Further, the electrons are contained electrostatically in a deep energy well, created by tuning an externally applied magnetic field. The simultaneous electrostatic confinement of electrons and magnetic confinement of ions avoids anomalous transport and facilitates classical containment of both electrons and ions. In this configuration, ions and electrons may have adequate density and temperature so that upon collisions they are fused together by nuclear force, thus releasing fusion energy. Moreover, the fusion fuel plasmas that can be used with the present confinement system and method are not limited to neutronic fuels only, but also advantageously include advanced fuels.

  11. Tomographic reconstruction of deformed internal structure of a field-reversed configuration

    SciTech Connect (OSTI)

    Asai, T.; Takahashi, T.; Kiguchi, T.; Matsuzawa, Y.; Nogi, Y.

    2006-07-15

    Deformation of the internal structure of a field-reversed configuration (FRC) was studied using a tomographic reconstruction technique. A simple and configurable tomographic system was developed, with which the time evolution of the FRC internal structure was reconstructed. In the latter phase of equilibrium, a FRC has a well-known global rotational instability with toroidal mode number n=2. It has been believed that elliptical deformation of the FRC allows interaction between the wall and the plasma, which terminates this configuration. However, these experiments revealed the FRC to deform into a dumbbell-like structure before the edge hits the chamber wall, leading to the disruption phase. In addition, an internal shift (toroidal mode number n=1) mode was observed in the equilibrium phase, followed by growth of n=2 rotational instability.

  12. Stochastic ion heating in a field-reversed configuration geometry by rotating magnetic fields

    SciTech Connect (OSTI)

    Cohen, S. A.; Landsman, A. S.; Glasser, A. H.

    2007-07-15

    Ion heating by application of rotating magnetic fields (RMFs) to a prolate field-reversed configuration (FRC) is explored by analytical and numerical techniques. For odd-parity RMFs (RMF{sub o}), perturbation analysis shows ions in figure-8 orbits gain energy at resonances of the RMF{sub o} frequency {omega}{sub R}, with the figure-8 orbital frequency {omega}. Since figure-8 orbits tend to gain the most energy from the RMF and are unlikely to escape in the cusp region (where most losses occur), they are optimal candidates for rapid stochastic heating, as compared to cyclotron and betatron orbits. Comparisons are made between heating caused by even- and odd-parity RMFs and between heating in currently operating and in reactor-scale FRC devices.

  13. Formation of a field reversed configuration for magnetic and electrostatic confinement of plasma

    SciTech Connect (OSTI)

    Rostoker, Norman; Binderbauer, Michl

    2003-12-16

    A system and method for containing plasma and forming a Field Reversed Configuration (FRC) magnetic topology are described in which plasma ions are contained magnetically in stable, non-adiabatic orbits in the FRC. Further, the electrons are contained electrostatically in a deep energy well, created by tuning an externally applied magnetic field. The simultaneous electrostatic confinement of electrons and magnetic confinement of ions avoids anomalous transport and facilitates classical containment of both electrons and ions. In this configuration, ions and electrons may have adequate density and temperature so that upon collisions they are fused together by nuclear force, thus releasing fusion energy. Moreover, the fusion fuel plasmas that can be used with the present confinement system and method are not limited to neutronic fuels only, but also advantageously include advanced fuels.

  14. A steady state field-reversed configuration with rotating magnetic fields

    SciTech Connect (OSTI)

    Ohnishi, Masami; Yamamoto, Yasushi; Yoshikawa, Kiyoshi; Kitagaki, Jiro; Ishida, Akio

    1995-12-31

    The numerical simulations were made on current sustainment of a field-reversed configuration (FRC) by a rotating magnetic field (RMF). The RMF externally applied just after producing the FRC by a theta pinch discharge is found to penetrate rapidly into the FRC, and to drive a steady current before the FRC collapses due to Joule dissipation. The minimum rotating magnetic field to sustain the equilibrium is also found to be as small as 10% of the axial magnetic field. The RMF`s with the mode number of m = 1 or 2 are found to provide the similar effects. The numerical results show that the method of applying an RMF to an FRC is considerably effective for sustaining the hot and dense FRC in the steady state.

  15. A new high performance field reversed configuration operating regime in the C-2 device

    SciTech Connect (OSTI)

    Tuszewski, M.; Smirnov, A.; Thompson, M. C.; Barnes, D.; Binderbauer, M. W.; Brown, R.; Bui, D. Q.; Clary, R.; Conroy, K. D.; Deng, B. H.; Dettrick, S. A.; Douglass, J. D.; Garate, E.; Glass, F. J.; Gota, H.; Guo, H.Y.; Gupta, D.; Gupta, S.; Kinley, J. S.; Knapp, K.; and others

    2012-05-15

    Large field reversed configurations (FRCs) are produced in the C-2 device by combining dynamic formation and merging processes. The good confinement of these FRCs must be further improved to achieve sustainment with neutral beam (NB) injection and pellet fuelling. A plasma gun is installed at one end of the C-2 device to attempt electric field control of the FRC edge layer. The gun inward radial electric field counters the usual FRC spin-up and mitigates the n = 2 rotational instability without applying quadrupole magnetic fields. Better plasma centering is also obtained, presumably from line-tying to the gun electrodes. The combined effects of the plasma gun and of neutral beam injection lead to the high performance FRC operating regime, with FRC lifetimes up to 3 ms and with FRC confinement times improved by factors 2 to 4.

  16. Multi-channel Doppler backscattering measurements in the C-2 field reversed configuration

    SciTech Connect (OSTI)

    Schmitz, L. Peebles, W. A.; Ruskov, E.; Deng, B. H.; Gota, H.; Gupta, D.; Tuszewski, M.; Douglass, J.; Binderbauer, M.; Tajima, T.

    2014-11-15

    A versatile heterodyne Doppler Backscattering (DBS) system is used to measure density fluctuation levels (in the wavenumber range kρ{sub s} ≤ 50), and the toroidal E × B flow velocity in the C-2 Field-Reversed Configuration (FRC). Six tunable frequencies in three waveguide bands (26 GHz ≤ f ≤ 90 GHz) are launched using monostatic beam optics, via a quasi-optical beam combiner/polarizer and an adjustable parabolic focusing mirror (inside the vacuum enclosure) achieving Gaussian beam spot sizes of 3–5.5 cm at the X/O-mode cutoff. The DBS system covers plasma densities of 0.8 × 10{sup 13} ≤ n{sub e} ≤ 1 × 10{sup 14} cm{sup −3}, and provides access to the FRC core (up to the field null) and across the FRC separatrix into the scrape-off layer plasma.

  17. Formation of a field reversed configuration for magnetic and electrostatic confinement of plasma

    DOE Patents [OSTI]

    Rostoker, Norman; Binderbauer, Michl; Qerushi, Artan; Tahsiri, Hooshang

    2006-02-07

    A system and method for containing plasma and forming a Field Reversed Configuration (FRC) magnetic topology are described in which plasma ions are contained magnetically in stable, non-adiabatic orbits in the FRC. Further, the electrons are contained electrostatically in a deep energy well, created by tuning an externally applied magnetic field. The simultaneous electrostatic confinement of electrons and magnetic confinement of ions avoids anomalous transport and facilitates classical containment of both electrons and ions. In this configuration, ions and electrons may have adequate density and temperature so that upon collisions they are fused together by nuclear force, thus releasing fusion energy. Moreover, the fusion fuel plasmas that can be used with the present confinement system and method are not limited to neutronic fuels only, but also advantageously include advanced fuels.

  18. Visible bremsstrahlung tomographic diagnostic for the pulsed high density field-reversed configuration experiment

    SciTech Connect (OSTI)

    Gota, H.; Andreason, S. P.; Votroubek, G. R.; Pihl, C. J.; Slough, J. T.

    2006-10-15

    A diagnostic suite for the source section of the pulsed high density field-reversed configuration (FRC) experiment has been constructed to investigate the equilibrium and stability of FRC plasmas. In particular, a visible bremsstrahlung tomographic system has been designed and implemented. Three types of tomographic analyses for FRCs are performed: a Fourier fit method (Cormack-Granetz), a maximum entropy method, and a minimum Fisher method utilizing code developed for the TCV tokamak experiment in Switzerland [Anton et al., Plasma Phys. Controled Fusion 38, 1849 (1996)]. Results from the different methods and end-on imaging from the fast-framing camera are compared showing relative agreement of FRC internal structures between all measurements.

  19. Stochastic Ion Heating in a Field-reversed Configuration Geometry by Rotating Magnetic Fields

    SciTech Connect (OSTI)

    S.A. Cohen, A.S. Landsman, and A.H. Glasser

    2007-06-25

    Ion heating by application of rotating magnetic fields (RMF) to a prolate field-reversed configuration(FRC) is explored by analytical and numerical techniques. For odd-parity RMF (RMFo), perturbation analysis shows ions in figure-8 orbits gain energy at resonances of the RMFo frequency, ωR, with the figure-8 orbital frequency, ω. Since figure-8 orbits tend to gain the most energy from the RMF and are unlikely to escape in the cusp region (where most losses occur), they are optimal candidates for rapid stochastic heating, as compared to cyclotron and betatron orbits. Comparisons are made between heating caused by even- and odd-parity RMFs and between heating in currently operating and in reactor-scale FRC devices.

  20. Field-reversed configuration formation scheme utilizing a spheromak and solenoid induction

    SciTech Connect (OSTI)

    Gerhardt, S. P.; Belova, E. V.; Yamada, M.; Ji, H.; Ren, Y.; McGeehan, B.; Inomoto, M.

    2008-03-15

    A new field-reversed configuration (FRC) formation technique is described, where a spheromak transitions to a FRC with inductive current drive. The transition is accomplished only in argon and krypton plasmas, where low-n kink modes are suppressed; spheromaks with a lighter majority species, such as neon and helium, either display a terminal tilt-mode, or an n=2 kink instability, both resulting in discharge termination. The stability of argon and krypton plasmas through the transition is attributed to the rapid magnetic diffusion of the currents that drive the kink-instability. The decay of helicity during the transition is consistent with that expected from resistivity. This observation indicates a new scheme to form a FRC plasma, provided stability to low-n modes is maintained, as well as a unique situation where the FRC is a preferred state.

  1. Overview of C-2 field-reversed configuration experiment plasma diagnostics

    SciTech Connect (OSTI)

    Gota, H. Thompson, M. C.; Tuszewski, M.; Binderbauer, M. W.

    2014-11-15

    A comprehensive diagnostic suite for field-reversed configuration (FRC) plasmas has been developed and installed on the C-2 device at Tri Alpha Energy to investigate the dynamics of FRC formation as well as to understand key FRC physics properties, e.g., confinement and stability, throughout a discharge. C-2 is a unique, large compact-toroid merging device that produces FRC plasmas partially sustained for up to ∼5 ms by neutral-beam (NB) injection and end-on plasma-guns for stability control. Fundamental C-2 FRC properties are diagnosed by magnetics, interferometry, Thomson scattering, spectroscopy, bolometry, reflectometry, and NB-related fast-ion/neutral diagnostics. These diagnostics (totaling >50 systems) are essential to support the primary goal of developing a deep understanding of NB-driven FRCs.

  2. Hall magnetohydrodynamics simulations of end-shorting induced rotation in field-reversed configurations

    SciTech Connect (OSTI)

    Macnab, A. I. D.; Milroy, R. D.; Kim, C. C.; Sovinec, C. R.

    2007-09-15

    End-shorting of the open field lines that surround a field-reversed configuration (FRC) is believed to contribute to its observed rotation. In this study, nonlinear extended magnetohydrodynamics (MHD) simulations were performed that detail the end-shorting process and the resulting spin-up of the FRC. The tangential component of the electric field E{sub T} is set to zero at the axial boundaries in an extended MHD model that includes the Hall and {nabla}P{sub e} terms. This shorting of the electric field leads to the generation of toroidal fields on the open field lines, which apply a torque leading to a rotation of the ions on the open field lines. The FRC then gains angular momentum through a viscous transfer from the open field line region. In addition, it is shown that spin-up is still induced when insulating boundaries are assumed.

  3. Depth profile of a time-reversal focus in an elastic solid

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

    Remillieux, Marcel C.; Anderson, Brian E.; Ulrich, T. J.; Le Bas, Pierre -Yves; Payan, Cedric

    2015-04-01

    The out-of-plane velocity component is focused on the flat surface of an isotropic solid sample using the principle of time reversal. This experiment is often reproduced in the context of nondestructive testing for imaging features near the surface of the sample. However, it is not clear how deep the focus extends into the bulk of the sample and what its profile is. In this paper, this question is answered using both numerical simulations and experimental data. The profiles of the foci are expressed in terms of the wavelengths of the dominant waves, based on the interpretation of the Lamb’s problemmore » and the use of the diffraction limit.« less

  4. Reversible monolayer-to-crystalline phase transition in amphiphilic silsesquioxane at the air-water interface

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

    Banerjee, R.; Sanyal, M. K.; Bera, M. K.; Gibaud, A.; Lin, B.; Meron, M.

    2015-02-17

    We report on the counter intuitive reversible crystallisation of two-dimensional monolayer of Trisilanolisobutyl Polyhedral Oligomeric SilSesquioxane (TBPOSS) on water surface using synchrotron x-ray scattering measurements. Amphiphilic TBPOSS form rugged monolayers and Grazing Incidence X-ray Scattering (GIXS) measurements reveal that the in-plane inter-particle correlation peaks, characteristic of two-dimensional system, observed before transition is replaced by intense localized spots after transition. The measured x-ray scattering data of the non-equilibrium crystalline phase on the air-water interface could be explained with a model that assumes periodic stacking of the TBPOSS dimers. These crystalline stacking relaxes upon decompression and the TBPOSS layer retains its initialmore » monolayer state. The existence of these crystals in compressed phase is confirmed by atomic force microscopy measurements by lifting the materials on a solid substrate.« less

  5. Reverse trade mission on the drilling and completion of geothermal wells

    SciTech Connect (OSTI)

    Not Available

    1989-09-09

    This draft report was prepared as required by Task No. 2 of the US Department of Energy, Grant No. DE-FG07-89ID12850 Reverse Trade Mission to Acquaint International Representatives with US Power Plant and Drilling Technology'' (mission). As described in the grant proposal, this report covers the reactions of attendees toward US technology, its possible use in their countries, and an evaluation of the mission by the staff leaders. Note this is the draft report of one of two missions carried out under the same contract number. Because of the diversity of the mission subjects and the different attendees at each, a separate report for each mission has been prepared. This draft report has been sent to all mission attendees, specific persons in the US Department of Energy and Los Alamos National Lab., the California Energy Commission (CEC), and various other governmental agencies.

  6. REVERSIBLE AND IRREVERSIBLE PASSIVATION OF A LA-NI-AL ALLOY

    SciTech Connect (OSTI)

    Shanahan, K.; Klein, J.

    2009-06-25

    This paper seeks to explore some of the effects of passivating a LaNi{sub 4.25}Al{sub 0.75} sample by air oxidation under controlled conditions. Passivation of this metal hydride alloy seems to have two distinct regimes. The first occurs with air oxidation at 80 C and 20 C. It is characterized by complete reversibility upon hydrogen readsorption, although said readsorption is hindered substantially at room temperature, requiring the material to be heated to produce the reactivation. The second regime is illustrated by 130 C air oxidation and is characterized by irreversible loss of hydrogen absorption capacity. This passivation does not hinder hydrogen readsorption into the remaining hydride material.

  7. Acoustic Longitudinal Field NIF Optic Feature Detection Map Using Time-Reversal & MUSIC

    SciTech Connect (OSTI)

    Lehman, S K

    2006-02-09

    We developed an ultrasonic longitudinal field time-reversal and MUltiple SIgnal Classification (MUSIC) based detection algorithm for identifying and mapping flaws in fused silica NIF optics. The algorithm requires a fully multistatic data set, that is one with multiple, independently operated, spatially diverse transducers, each transmitter of which, in succession, launches a pulse into the optic and the scattered signal measured and recorded at every receiver. We have successfully localized engineered ''defects'' larger than 1 mm in an optic. We confirmed detection and localization of 3 mm and 5 mm features in experimental data, and a 0.5 mm in simulated data with sufficiently high signal-to-noise ratio. We present the theory, experimental results, and simulated results.

  8. Device for adapting continuously variable transmissions to infinitely variable transmissions with forward-neutral-reverse capabilities

    DOE Patents [OSTI]

    Wilkes, Donald F. (Albuquerque, NM); Purvis, James W. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM)

    1997-01-01

    An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.

  9. Reversible Electro-Optic Device Employing Aprotic Molten Salts And Method

    DOE Patents [OSTI]

    Warner, Benjamin P. (Los Alamos, NM); McCleskey, T. Mark (Los Alamos, NM); Burrell, Anthony K. (Los Alamos, NM); Hall, Simon B. (Palmerston North, NZ)

    2005-03-01

    A single-compartment reversible mirror device having a solution of aprotic molten salt, at least one soluble metal-containing species comprising metal capable of being electrodeposited, and at least one anodic compound capable of being oxidized was prepared. The aprotic molten salt is liquid at room temperature and includes lithium and/or quaternary ammonium cations, and anions selected from trifluoromethylsulfonate (CF.sub.3 SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3 SO.sub.2).sub.2 N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3 CF.sub.2 SO.sub.2).sub.2 N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3 SO.sub.2).sub.3 C.sup.-). A method for preparing substantially pure molten salts is also described.

  10. Reversible electro-optic device employing aprotic molten salts and method

    DOE Patents [OSTI]

    Warner, Benjamin P. (Los Alamos, NM); McCleskey, T. Mark (Los Alamos, NM); Burrell, Anthony K. (Los Alamos, NM); Hall, Simon B. (Palmerston North, NZ)

    2008-01-08

    A single-compartment reversible mirror device having a solution of aprotic molten salt, at least one soluble metal-containing species comprising metal capable of being electrodeposited, and at least one anodic compound capable of being oxidized was prepared. The aprotic molten salt is liquid at room temperature and includes lithium and/or quaternary ammonium cations, and anions selected from trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3C.sup.-). A method for preparing substantially pure molten salts is also described.

  11. Confinement improvement with rf poloidal current drive in the reversed-field pinch

    SciTech Connect (OSTI)

    Hokin, S.; Sarff, J.; Sovinec, C.; Uchimoto, E.

    1994-03-08

    External control of the current profile in a reversed-field pinch (RFP), by means such as rf poloidal current drive, may have beneficial effects well beyond the direct reduction of Ohmic input power due to auxiliary heating. Reduction of magnetic turbulence associated with the dynamo, which drives poloidal current in a conventional RFP, may allow operation at lower density and higher electron temperature, for which rf current drive becomes efficient and the RFP operates in a more favorable regime on the n{tau} vs T diagram. Projected parameters for RFX at 2 MA axe studied as a concrete example. If rf current drive allows RFX to operate with {beta} = 10% (plasma energy/magnetic energy) at low density (3 {times} 10{sup 19} m{sup {minus}3}) with classical resistivity (i.e. without dynamo-enhanced power input), 40 ms energy confinement times and 3 keV temperatures will result, matching the performance of tokamaks of similar size.

  12. Understanding the Initial Stages of Reversible Mg Deposition and Stripping in Inorganic Non-Aqueous Electrolytes

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

    Canepa, Pieremanuele; Gautam, Gopalakrishnan Sai; Malik, Rahul; Jayaraman, Saivenkataraman; Rong, Ziqin; Zavadil, Kevin R.; Persson, Kristin; Ceder, Gerbrand

    2015-04-08

    Multivalent (MV) battery architectures based on pairing a Mg metal anode with a high-voltage (~3 V) intercalation cathode offer a realistic design pathway toward significantly surpassing the energy storage performance of traditional Li-ion-based batteries, but there are currently only few electrolyte systems that support reversible Mg deposition. Using both static first-principles calculations and ab initio molecular dynamics, we perform a comprehensive adsorption study of several salt and solvent species at the interface of Mg metal with an electrolyte of Mg2+ and Cl–dissolved in liquid tetrahydrofuran (THF). Our findings not only provide a picture of the stable species at the interfacemore » but also explain how this system can support reversible Mg deposition, and as such, we provide insights in how to design other electrolytes for Mg plating and stripping. Furthermore, the active depositing species are identified to be (MgCl)+ monomers coordinated by THF, which exhibit preferential adsorption on Mg compared to possible passivating species (such as THF solvent or neutral MgCl2 complexes). We found that upon deposition, the energy to desolvate these adsorbed complexes and facilitate charge transfer is shown to be small (~61–46.2 kJ mol–1 to remove three THF from the strongest adsorbing complex), and the stable orientations of the adsorbed but desolvated (MgCl)+ complexes appear to be favorable for charge transfer. Finally, observations of Mg–Cl dissociation at the Mg surface at very low THF coordinations (0 and 1) suggest that deleterious Cl incorporation in the anode may occur upon plating. In the stripping process, this is beneficial by further facilitating the Mg removal reaction.« less

  13. Precise discussion of time-reversal asymmetries in B-meson decays

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

    Morozumi, Takuya; Okane, Hideaki; Umeeda, Hiroyuki

    2015-02-26

    BaBar collaboration announced that they observed time reversal (T) asymmetry through B meson system. In the experiment, time dependencies of two distinctive processes, B_ →B¯0 and B¯0 → B_ (– expresses CP value) are compared with each other. In our study, we examine event number difference of these two processes. In contrast to the BaBar asymmetry, the asymmetry of events number includes the overall normalization difference for rates. Time dependence of the asymmetry is more general and it includes terms absent in one used by BaBar collaboration. Both of the BaBar asymmetry and ours are naively thought to be T-oddmore »since two processes compared are related with flipping time direction. We investigate the time reversal transformation property of our asymmetry. Using our notation, one can see that the asymmetry is not precisely a T-odd quantity, taking into account indirect CP and CPT violation of K meson systems. The effect of ϵK is extracted and gives rise to O(10–3) contribution. The introduced parameters are invariant under rephasing of quarks so that the coefficients of our asymmetry are expressed as phase convention independent quantities. Some combinations of the asymmetry enable us to extract parameters for wrong sign decays of Bd meson, CPT violation, etc. As a result, we also study the reason why the T-even terms are allowed to contribute to the asymmetry, and find that several conditions are needed for the asymmetry to be a T-odd quantity.« less

  14. Understanding the Initial Stages of Reversible Mg Deposition and Stripping in Inorganic Non-Aqueous Electrolytes

    SciTech Connect (OSTI)

    Canepa, Pieremanuele; Gautam, Gopalakrishnan Sai; Malik, Rahul; Jayaraman, Saivenkataraman; Rong, Ziqin; Zavadil, Kevin R.; Persson, Kristin; Ceder, Gerbrand

    2015-04-08

    Multivalent (MV) battery architectures based on pairing a Mg metal anode with a high-voltage (~3 V) intercalation cathode offer a realistic design pathway toward significantly surpassing the energy storage performance of traditional Li-ion-based batteries, but there are currently only few electrolyte systems that support reversible Mg deposition. Using both static first-principles calculations and ab initio molecular dynamics, we perform a comprehensive adsorption study of several salt and solvent species at the interface of Mg metal with an electrolyte of Mg2+ and Cldissolved in liquid tetrahydrofuran (THF). Our findings not only provide a picture of the stable species at the interface but also explain how this system can support reversible Mg deposition, and as such, we provide insights in how to design other electrolytes for Mg plating and stripping. Furthermore, the active depositing species are identified to be (MgCl)+ monomers coordinated by THF, which exhibit preferential adsorption on Mg compared to possible passivating species (such as THF solvent or neutral MgCl2 complexes). We found that upon deposition, the energy to desolvate these adsorbed complexes and facilitate charge transfer is shown to be small (~6146.2 kJ mol1 to remove three THF from the strongest adsorbing complex), and the stable orientations of the adsorbed but desolvated (MgCl)+ complexes appear to be favorable for charge transfer. Finally, observations of MgCl dissociation at the Mg surface at very low THF coordinations (0 and 1) suggest that deleterious Cl incorporation in the anode may occur upon plating. In the stripping process, this is beneficial by further facilitating the Mg removal reaction.

  15. Curvature and ionization-induced reversible hydrogen storage in metalized hexagonal B{sub 36}

    SciTech Connect (OSTI)

    Liu, Chun-Sheng Wang, Xiangfu; Yan, Xiaohong; Ye, Xiao-Juan; Zeng, Zhi

    2014-11-21

    The synthesis of quasiplanar boron clusters (B{sub 36}) with a central hexagonal hole provides the first experimental evidence that a single-atomic-layer borophene with hexagonal vacancies is potentially viable [Z. Piazza, H. Hu, W. Li, Y. Zhao, J. Li, and L. S. Wang, Nat. Commun. 5, 3113 (2014)]. However, owing to the hexagonal holes, tunning the electronic and physical properties of B{sub 36} through chemical modifications is not fully understood. Based on (van der Waals corrected-) density functional theory, we show that Li adsorbed on B{sub 36} and B{sub 36}{sup ?} clusters can serve as reversible hydrogen storage media. The present results indicate that the curvature and ionization of substrates can enhance the bond strength of Li due to the energetically favorable B 2p-Li 2p orbitals hybridization. Both the polarization mechanism and the orbital hybridization between H-s orbitals and Li-2s2p orbitals contribute to the adsorption of H{sub 2} molecules and the resulting adsorption energy lies between the physisorbed and chemisorbed states. Interestingly, the number of H{sub 2} in the hydrogen storage medium can be measured by the appearance of the negative differential resistance behavior at different bias voltage regions. Furthermore, the cluster-assembled hydrogen storage materials constructed by metalized B{sub 36} clusters do not cause a decrease in the number of adsorbed hydrogen molecules per Li. The system reported here is favorable for the reversible hydrogen adsorption/desorption at ambient conditions.

  16. Particle count monitoring of reverse osmosis water treatment for removal of low-level radionuclides

    SciTech Connect (OSTI)

    Moritz, E.J.; Hoffman, C.R.; Hergert, T.R.

    1995-03-01

    Laser diode particle counting technology and analytical measurements were used to evaluate a pilot-scale reverse osmosis (RO) water treatment system for removal of particulate matter and sub-picocurie low-level radionuclides. Stormwater mixed with Waste Water Treatment Plant (WWTP) effluent from the Rocky Flats Environmental Technology Site (RFETS), formerly a Department of Energy (DOE) nuclear weapons production facility, were treated. No chemical pretreatment of the water was utilized during this study. The treatment system was staged as follows: multimedia filtration, granular activated carbon adsorption, hollow tube ultrafiltration, and reverse osmosis membrane filtration. Various recovery rates and two RO membrane models were tested. Analytical measurements included total suspended solids (TSS), total dissolved solids (TDS), gross alpha ({alpha}) and gross beta ({beta}) activity, uranium isotopes {sup 233/234}U and {sup 238}U, plutonium {sup 239/240}Pu, and americium {sup 241}Am. Particle measurement between 1--150 microns ({mu}) included differential particle counts (DPC), and total particle counts (TPC) before and after treatment at various sampling points throughout the test. Performance testing showed this treatment system produced a high quality effluent in clarity and purity. Compared to raw water levels, TSS was reduced to below detection of 5 milligrams per liter (mg/L) and TDS reduced by 98%. Gross {alpha} was essentially removed 100%, and gross {beta} was reduced an average of 94%. Uranium activity was reduced by 99%. TPC between 1-150{mu} were reduced by an average 99.8% to less than 1,000 counts per milliliter (mL), similar in purity to a good drinking water treatment plant. Raw water levels of {sup 239/240}Pu and {sup 241}Am were below reliable quantitation limits and thus no removal efficiencies could be determined for these species.

  17. On-chip single-copy real-time reverse-transcription PCR in isolated picoliter droplets

    SciTech Connect (OSTI)

    Beer, N R; Wheeler, E; Lee-Houghton, L; Watkins, N; Nasarabadi, S; Hebert, N; Leung, P; Arnold, D; Bailey, C; Colston, B

    2007-12-19

    The first lab-on-chip system for picoliter droplet generation and RNA isolation, followed by reverse transcription, and PCR amplification with real-time fluorescence detection in the trapped droplets has been developed. The system utilized a shearing T-junction in a fused silica device to generate a stream of monodisperse picoliter-scale droplets that were isolated from the microfluidic channel walls and each other by the oil phase carrier. An off-chip valving system stopped the droplets on-chip, allowing thermal cycling for reverse transcription and subsequent PCR amplification without droplet motion. This combination of the established real-time reverse transcription-PCR assay with digital microfluidics is ideal for isolating single-copy RNA and virions from a complex environment, and will be useful in viral discovery and gene-profiling applications.

  18. Experimental and ab initio studies of the reactive processes in gas phase i-C{sub 3}H{sub 7}Br and i-C{sub 3}H{sub 7}OH collisions with potassium ions

    SciTech Connect (OSTI)

    Lpez, E.; Lucas, J. M.; Andrs, J. de; Albert, M.; Aguilar, A., E-mail: a.aguilar@ub.edu [Departament de Qumica Fsica, Institut de Qumica Terica i Computacional (IQTCUB), Universitat de Barcelona, Mart i Franqus, 1, 08028 Barcelona (Spain); Bofill, J. M. [Departament de Qumica Orgnica, Institut de Qumica Terica i Computacional (IQTCUB), Universitat de Barcelona, Mart i Franqus, 1, 08028 Barcelona (Spain); Bassi, D. [Dipartimento di Fisica, Universit degli Studi di Trento, 38123 Povo-Trento (Italy)

    2014-10-28

    Collisions between potassium ions and neutral i-C{sub 3}H{sub 7}Br and i-C{sub 3}H{sub 7}OH, all in their electronic ground state, have been studied in the 0.1010.00 eV center of mass (CM) collision energy range, using the radiofrequency-guided ion beam technique. In K{sup +} + i-C{sub 3}H{sub 7}Br collisions KHBr{sup +} formation was observed and quantified, while the analogous KH{sub 2}O{sup +} formation in K{sup +} + i-C{sub 3}H{sub 7}OH was hardly detected. Moreover, formation of the ion-molecule adducts and their decomposition leading to C{sub 3}H{sub 7}{sup +} and either KBr or KOH, respectively, have been observed. For all these processes, absolute cross-sections were measured as a function of the CM collision energy. Ab initio structure calculations at the MP2 level have given information about the potential energy surfaces (PESs) involved. In these, different stationary points have been characterized using the reaction coordinate method, their connectivity being ensured by using the intrinsic-reaction-coordinate method. From the measured excitation function for KHBr{sup +} formation the corresponding thermal rate constant at 303 K has been calculated. The topology of the calculated PESs allows an interpretation of the main features of the reaction dynamics of both systems, and in particular evidence the important role played by the potential energy wells in controlling the reactivity for the different reaction channels.

  19. Reversible elastic deformation of functionalized sp{sup 2} carbon at pressures of up to 33?GPa

    SciTech Connect (OSTI)

    Soignard, Emmanuel; Hochheimer, Hans D.; Yarger, Jeff; Raj, Rishi

    2014-10-06

    We show that sp{sup 2} carbon bonded to silicon and oxygen can withstand reversible elastic deformation at pressures of up to 33?GPa. These experiments were carried out in a diamond anvil cell. In-situ Raman spectroscopy was employed to record the reversibility of elastic deformation by measuring the movement in the D and G peaks of carbon. Above 33?GPa the material, a silicon oxycarbide, transforms into an unidentified state which is retained upon unloading down to ambient pressure. Thermodynamical analysis suggests that the material could have transformed into a crystalline state at these ultrahigh pressures, driven by mechanical work.

  20. Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly technical report, July 1, 1996--September 31, 1996

    SciTech Connect (OSTI)

    Hunt, T.; Sjostrom, S.; Smith, J.

    1996-11-06

    The overall objective of this two phase program is to investigate the use of dry carbon-based sorbents for mercury control. This information is important to the utility industry in anticipation of pending regulations. During Phase I, a bench-scale field test device that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse has been designed, built and integrated with an existing pilot-scale facility at PSCo`s Comanche Station. Up to three candidate sorbents will be injected into the flue gas stream upstream of the test device to and mercury concentration measurements will be made to determine the mercury removal efficiency for each sorbent. During the Phase II effort, component integration for the most promising dry sorbent technology shall be tested at the 5000 acfm pilot-scale.

  1. Apparatus and method for controlling the rotary airlocks in a coal processing system by reversing the motor current rotating the air lock

    DOE Patents [OSTI]

    Groombridge, Clifton E. (Hardin, MT)

    1996-01-01

    An improvement to a coal processing system where hard materials found in the coal may cause jamming of either inflow or outflow rotary airlocks, each driven by a reversible motor. The instantaneous current used by the motor is continually monitored and compared to a predetermined value. If an overcurrent condition occurs, indicating a jamming of the airlock, a controller means starts a "soft" reverse rotation of the motor thereby clearing the jamming. Three patterns of the motor reversal are provided.

  2. THE MAGNETIZATION DEGREE OF THE OUTFLOW POWERING THE HIGHLY POLARIZED REVERSE-SHOCK EMISSION OF GRB 120308A

    SciTech Connect (OSTI)

    Zhang, Shuai; Jin, Zhi-Ping; Wei, Da-Ming, E-mail: jin@pmo.ac.cn, E-mail: dmwei@pmo.ac.cn [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, 210008 (China)

    2015-01-01

    GRB 120308A, a long duration ?-ray burst (GRB) detected by Swift, was distinguished by a highly polarized early optical afterglow emission that strongly suggests an ordered magnetic field component in the emitting region. In this work, we model the optical and X-ray emission in the reverse and forward shock scenario and show that the strength of the magnetic field in the reverse-shock region is ?10 times stronger than that in the forward shock region. Consequently, the outflow powering the highly polarized reverse-shock optical emission was mildly magnetized at a degree of ? ? a few percent. Considering the plausible magnetic energy dissipation in both the acceleration and prompt emission phases of the GRB outflow, the afterglow data of GRB 120308A provides us with compelling evidence that, at least for some GRBs, a nonignorable fraction of the energy was released in the form of Poynting flux, confirming the finding first made in the reverse-forward shock emission modeling of the optical afterglow of GRB 990123 by Fan etal. in 2002 and Zhang etal. in 2003.

  3. Catalyzed Nano-Framework Stablized High Density Reversible Hydrogen Storage Systems

    SciTech Connect (OSTI)

    Tang, Xia; Opalka, Susanne M.; Mosher, Daniel A; Laube, Bruce L; Brown, Ronald J; Vanderspurt, Thomas H; Arsenault, Sarah; Wu, Robert; Strickler, Jamie; Ronnebro, Ewa; Boyle, Tim; Cordaro, Joseph

    2010-06-30

    A wide range of high capacity on-board rechargeable material candidates have exhibited non-ideal behavior related to irreversible hydrogen discharge / recharge behavior, and kinetic instability or retardation. This project addresses these issues by incorporating solvated and other forms of complex metal hydrides, with an emphasis on borohydrides, into nano-scale frameworks of low density, high surface area skeleton materials to stabilize, catalyze, and control desorption product formation associated with such complex metal hydrides. A variety of framework chemistries and hydride / framework combinations were investigated to make a relatively broad assessment of the method's potential. In this project, the hydride / framework interactions were tuned to decrease desorption temperatures for highly stable compounds or increase desorption temperatures for unstable high capacity compounds, and to influence desorption product formation for improved reversibility. First principle modeling was used to explore heterogeneous catalysis of hydride reversibility by modeling H2 dissociation, hydrogen migration, and rehydrogenation. Atomic modeling also demonstrated enhanced NaTi(BH4)4 stabilization at nano-framework surfaces modified with multi-functional agents. Amine multi-functional agents were found to have more balanced interactions with nano-framework and hydride clusters than other functional groups investigated. Experimentation demonstrated that incorporation of Ca(BH4)2 and Mg(BH4)2 in aerogels enhanced hydride desorption kinetics. Carbon aerogels were identified as the most suitable nano-frameworks for hydride kinetic enhancement and high hydride loading. High loading of NaTi(BH4)4 ligand complex in SiO2 aerogel was achieved and hydride stability was improved with the aerogel. Although improvements of desorption kinetics was observed, the incorporation of Ca(BH4)2 and Mg(BH4)2 in nano-frameworks did not improve their H2 absorption due to the formation of stable alkaline earth B12H12 intermediates upon rehydrogenation. This project primarily investigated the effect of nano-framework surface chemistry on hydride properties, while the effect of pore size is the focus area of other efforts (e.g., HRL, Sandia National Laboratories (SNL) etc.) within the Metal Hydride Center of Excellence (MHCoE). The projects were complementary in gaining an overall understanding of the influence of nano-frameworks on hydride behavior.

  4. Principal physics of rotating magnetic-field current drive of field reversed configurations

    SciTech Connect (OSTI)

    Hoffman, A.L.; Guo, H.Y.; Miller, K.E.; Milroy, R.D.

    2006-01-15

    After extensive experimentation on the Translation, Confinement, and Sustainment rotating magnetic-field (RMF)-driven field reversed configuration (FRC) device [A. L. Hoffman et al., Fusion Sci. Technol. 41, 92 (2002)], the principal physics of RMF formation and sustainment of standard prolate FRCs inside a flux conserver is reasonably well understood. If the RMF magnitude B{sub {omega}} at a given frequency {omega} is high enough compared to other experimental parameters, it will drive the outer electrons of a plasma column into near synchronous rotation, allowing the RMF to penetrate into the plasma. If the resultant azimuthal current is strong enough to reverse an initial axial bias field B{sub o} a FRC will be formed. A balance between the RMF applied torque and electron-ion friction will determine the peak plasma density n{sub m}{proportional_to}B{sub {omega}}/{eta}{sup 1/2}{omega}{sup 1/2}r{sub s}, where r{sub s} is the FRC separatrix radius and {eta} is an effective weighted plasma resistivity. The plasma total temperature T{sub t} is free to be any value allowed by power balance as long as the ratio of FRC diamagnetic current, I{sup '}{sub dia}{approx_equal}2B{sub e}/{mu}{sub o}, is less than the maximum possible synchronous current, I{sup '}{sub sync}=e{omega}r{sub s}{sup 2}/2. The RMF will self-consistently penetrate a distance {delta}{sup *} governed by the ratio {zeta}=I{sup '}{sub dia}/I{sup '}{sub sync}. Since the FRC is a diamagnetic entity, its peak pressure p{sub m}=n{sub m}kT{sub t} determines its external magnetic field B{sub e}{approx_equal}(2{mu}{sub o}p{sub m}){sup 1/2}. Higher FRC currents, magnetic fields, and poloidal fluxes can thus be obtained, with the same RMF parameters, simply by raising the plasma temperature. Higher temperatures have also been noted to reduce the effective plasma resistivity, so that these higher currents can be supported with surprisingly little increase in absorbed RMF power.

  5. Plasmon-enhanced reverse water gas shift reaction over oxide supported Au catalysts

    SciTech Connect (OSTI)

    Upadhye, AA; Ro, I; Zeng, X; Kim, HJ; Tejedor, I; Anderson, MA; Dumesic, JA; Huber, GW

    2015-01-01

    We show that localized surface plasmon resonance (LSPR) can enhance the catalytic activities of different oxide-supported Au catalysts for the reverse water gas shift (RWGS) reaction. Oxide-supported Au catalysts showed 30 to 1300% higher activity for RWGS under visible light compared to dark conditions. Au/TiO2 catalyst prepared by the deposition-precipitation (DP) method with 3.5 nm average Au particle size showed the highest activity for the RWGS reaction. Visible light is converted into chemical energy for this reaction with up to a 5% overall efficiency. A shift in the apparent activation energy (from 47 kJ mol(-1) in dark to 35 kJ mol(-1) in light) and apparent reaction order with respect to CO2 (from 0.5 in dark to 1.0 in light) occurs due to the LSPR. Our kinetic results indicate that the LSPR increases the rate of either the hydroxyl hydrogenation or carboxyl decomposition more than any other steps in the reaction network.

  6. Passive Superconducting Flux Conservers for Rotating-Magnetic-Field-Driven Field-Reversed Configurations

    SciTech Connect (OSTI)

    Oz, E.; Myers, C. E.; Edwards, M. R.; Berlinger, B.; Brooks, A.; Cohen, S. A.

    2011-01-05

    The Princeton Field-Reversed Configuration (PFRC) experiment employs an odd-parity rotating magnetic field (RMFo) current drive and plasma heating system to form and sustain high-? plasmas. For radial confinement, an array of coaxial, internal, passive, flux-conserving (FC) rings applies magnetic pressure to the plasma while still allowing radio-frequency RMFo from external coils to reach the plasma. The 3 ms pulse duration of the present experiment is limited by the skin time (?fc) of its room-temperature copper FC rings. To explore plasma phenomena with longer characteristic times, the pulse duration of the next-generation PFRC-2 device will exceed 100 ms, necessitating FC rings with (?fc > 300 ms. In this paper we review the physics of internal, discrete, passive FCs and describe the evolution of the PFRC's FC array. We then detail new experiments that have produced higher performance FC rings that contain embedded high-temperature superconducting (HTS) tapes. Several HTS tape winding configurations have been studied and a wide range of extended skin times, from 0.4 s to over 103 s, has been achieved. The new FC rings must carry up to 3 kA of current to balance the expected PFRC-2 plasma pressure, so the dependence of the HTS-FC critical current on the winding configuration and temperature was also studied. From these experiments, the key HTS-FC design considerations have been identified and HTS-FC rings with the desired performance characteristics have been produced.

  7. The Role of Axisymmetric Reconnection Events in JET Discharges with Extreme Shear Reversal

    SciTech Connect (OSTI)

    B.C. Stratton; J.A. Breslau; R.V. Budny; S.C. Jardin; W. Park; H.R. Strauss; L.E. Zakharov; B. Alper; V. Drozdov; N.C. Hawkes; S. Reyes-Cortes; and Contributors to the EFDA-JET Work Programme

    2001-12-03

    Injection of Lower Hybrid Heating and Current Drive into the current ramp-up phase of Joint European Torus (JET) discharges can produce extremely reversed q-profiles characterized by a core region of very small or zero current density (within Motional Stark Effect diagnostic measurement errors) and q(subscript min) > 1. T(subscript e)-profiles show sawtooth-like collapses and the presence of an internal transport barrier. Accurate equilibrium reconstructions of these discharges are obtained using the ESC code, which was recently extended to allow equilibrium reconstructions in which a free boundary solver determines the plasma boundary and a fixed boundary solver provides the magnetic geometry and current density profile. The core current density does not appear to go negative, although current diffusion calculations indicate that sufficient non-inductive current drive to cause this is present. This is explained by nonlinear resistive MHD simulations in toroidal geometry which predict that these discharges undergo n=0 reconnection events (axisymmetric sawteeth) that redistribute the current to hold the core current density near zero.

  8. Electrolytic conditioning of a magnesium aluminum chloride complex for reversible magnesium deposition

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

    Barile, Christopher J.; Barile, Elizabeth C.; Zavadil, Kevin R.; Nuzzo, Ralph G.; Gewirth, Andrew A.

    2014-12-04

    We describe in this report the electrochemistry of Mg deposition and dissolution from the magnesium aluminum chloride complex (MACC). The results define the requirements for reversible Mg deposition and definitively establish that voltammetric cycling of the electrolyte significantly alters its composition and performance. Elemental analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (SEM-EDS) results demonstrate that irreversible Mg and Al deposits form during early cycles. Electrospray ionization-mass spectrometry (ESI-MS) data show that inhibitory oligomers develop in THF-based solutions. These oligomers form via the well-established mechanism of a cationic ring-opening polymerization of THF during the initial synthesis of the MACC andmore » under resting conditions. In contrast, MACC solutions in 1,2-dimethoxyethane (DME), an acyclic solvent, do not evolve as dramatically at open circuit potential. Furthermore, we propose a mechanism describing how the conditioning process of the MACC in THF improves its performance by both tuning the Mg:Al stoichiometry and eliminating oligomers.« less

  9. Conventional empirical law reverses in the phase transitions of 122-type iron-based superconductors

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

    Yu, Zhenhai; Wang, Lin; Wang, Luhong; Liu, Haozhe; Zhao, Jinggeng; Li, Chunyu; Sinogeikin, Stanislav; Wu, Wei; Luo, Jianlin; Wang, Nanlin; et al

    2014-11-24

    Phase transition of solid-state materials is a fundamental research topic in condensed matter physics, materials science and geophysics. It has been well accepted and widely proven that isostructural compounds containing different cations undergo same pressure-induced phase transitions but at progressively lower pressures as the cation radii increases. However, we discovered that this conventional law reverses in the structural transitions in 122-type iron-based superconductors. In this report, a combined low temperature and high pressure X-ray diffraction (XRD) measurement has identified the phase transition curves among the tetragonal (T), orthorhombic (O) and the collapsed-tetragonal (cT) phases in the structural phase diagram ofmore » the iron-based superconductor AFe2As2 (A = Ca, Sr, Eu, and Ba). As a result, the cation radii dependence of the phase transition pressure (T → cT) shows an opposite trend in which the compounds with larger ambient radii cations have a higher transition pressure.« less

  10. Local transport barrier formation and relaxation in reverse-shear plasmas on the TFTR tokamak

    SciTech Connect (OSTI)

    Synakowski, E.J.; Beer, M.A.; Batha, S.H.

    1997-02-01

    The roles of turbulence stabilization by sheared E x B flow and Shafranov-shift gradients are examined for TFTR. Enhanced Reverse-Shear plasmas. Both effects in combination provide the basis of a positive-feedback model that predicts reinforced turbulence suppression with increasing pressure gradient. Local fluctuation behavior at the onset of ERS confinement is consistent with this framework. The power required for transitions into the ERS regime are lower when high power neutral beams are applied earlier in the current profile evolution, consistent with the suggestion that both effects play a role. Separation of the roles of E x B and Shafranov shift effects was performed by varying the E x B shear through changes in the toroidal velocity with nearly-steady-state pressure profiles. Transport and fluctuation levels increase only when E x B shearing rates are driven below a critical value that is comparable to the fastest linear growth rates of the dominant instabilities. While a turbulence suppression criterion that involves the ratio of shearing to linear growth rates is in accord with many of these results, the existence of hidden dependencies of the criterion is suggested in experiments where the toroidal field was varied. The forward transition into the ERS regime has also been examined in strongly rotating plasmas. The power threshold is higher with unidirectional injection than with balanced injection.

  11. Langmuir probe diagnostic suite in the C-2 field-reversed configuration

    SciTech Connect (OSTI)

    Roche, T. Armstrong, S.; Knapp, K.; Slepchenkov, M.; Sun, X.

    2014-11-15

    Several in situ probes have been designed and implemented into the diagnostic array of the C-2 field-reversed configuration (FRC) at Tri Alpha Energy [M. Tuszewski et al. (the TAE Team), Phys. Rev. Lett. 108, 255008 (2012)]. The probes are all variations on the traditional Langmuir probe. They include linear arrays of triple probes, linear arrays of single-tipped swept probes, a multi-faced Gundestrup probe, and an ion-sensitive probe. The probes vary from 5 to 7 mm diameter in size to minimize plasma perturbations. They also have boron nitride outer casings that prevent unwanted electrical breakdown and reduce the introduction of impurities. The probes are mounted on motorized linear-actuators allowing for programmatic scans of the various plasma parameters over the course of several shots. Each probe has a custom set of electronics that allows for measurement of the desired signals. High frequency ( > 5MHz) analog optical-isolators ensure that plasma parameters can be measured at sub-microsecond time scales while providing electrical isolation between machine and data acquisition systems. With these probes time-resolved plasma parameters (temperature, density, spatial potential, flow, and electric field) can be directly/locally measured in the FRC jet and edge/scrape-off layer.

  12. Tomographic imaging system for measuring impurity line emission in a field-reversed configuration

    SciTech Connect (OSTI)

    Roche, T.; Heidbrink, W. W.; McWilliams, R.; Bolte, N.; Garate, E.; Wessel, F.

    2012-10-15

    A 16 chord optical tomography system has been developed and implemented in the flux coil generated-field reversed configuration (FRC). The chords are arranged in two fans of eight, which cover {approx}35% of the vessel area at the midplane. Each illuminate separate photomultiplier tubes (PMTs) which are fitted with narrow band-pass filters. In this case, filters are centered at 434.8 nm to measure emission from singly ionized argon. PMT crosstalk is negligible. Background noise due to electron radiation and H{sub {gamma}} line radiation is <10% of argon emission. The spatial resolution of the reconstruction is 1.5 cm. Argon is introduced using a puff valve and tube designed to impart the gas into the system as the FRC is forming. Reconstruction of experimental data results in time-dependent, 2D emissivity profiles of the impurity ions. Analysis of these data show radial, cross-field diffusion to be in the range of 10-10{sup 3} m{sup 2}/s during FRC equilibrium.

  13. Equilibrium paradigm for field-reversed configurations and application to experiments

    SciTech Connect (OSTI)

    Steinhauer, Loren C.; Intrator, T. P.

    2009-07-15

    Fresh insights on field-reversed configurations (FRCs) are incorporated in a new paradigm for equilibria. In particular four new or unappreciated properties are accounted for: an empirically based scrape-off layer thickness; a new, more accurate axial force balance relation; viscous force regularity at the O-point; and the broken-surface effect. The new paradigm corrects glaring defects of previous models (rigid rotor, Hill's vortex). Further, the new paradigm is simple enough to be easily used as an interpretive tool despite the limited data suite in most experiments. It is applied to the newly enhanced FRC data compendium, a database of 69 records from 15 facilities. Several important observations and corrections on the previous understanding of FRCs follow, three of which stand out. (1) The traditional axial force balance ('average-{beta}' relation) gives an inaccurate scaling with the separatrix-to-wall radius ratio. (2) The improved equilibrium paradigm yields separatrix particle transport rates of 3-5 m{sup 2}/s for 'best confinement' examples; this is a factor of three lower than crude 'bulk' estimates commonly used. (3) The transport compared to the Bohm rate shows a great deal of scatter (40% scatter/mean ratio), i.e., 'Bohm' is not a useful representation for transport scaling.

  14. Extended magnetohydrodynamic simulations of field reversed configuration formation and sustainment with rotating magnetic field current drive

    SciTech Connect (OSTI)

    Milroy, R. D.; Kim, C. C.; Sovinec, C. R.

    2010-06-15

    Three-dimensional simulations of field reversed configuration (FRC) formation and sustainment with rotating magnetic field (RMF) current drive have been performed with the NIMROD code [C. R. Sovinec et al., J. Comput. Phys. 195, 355 (2004)]. The Hall term is a zeroth order effect with strong coupling between Fourier components, and recent enhancements to the NIMROD preconditioner allow much larger time steps than was previously possible. Boundary conditions to capture the effects of a finite length RMF antenna have been added, and simulations of FRC formation from a uniform background plasma have been performed with parameters relevant to the translation, confinement, and sustainment-upgrade experiment at the University of Washington [H. Y. Guo, A. L. Hoffman, and R. D. Milroy, Phys. Plasmas 14, 112502 (2007)]. The effects of both even-parity and odd-parity antennas have been investigated, and there is no evidence of a disruptive instability for either antenna type. It has been found that RMF effects extend considerably beyond the ends of the antenna, and that a large n=0 B{sub t}heta can develop in the open-field line region, producing a back torque opposing the RMF.

  15. Rotating magnetic field current drive of high-temperature field reversed configurations with high {zeta} scaling

    SciTech Connect (OSTI)

    Guo, H. Y.; Hoffman, A. L.; Milroy, R. D.

    2007-11-15

    Greatly reduced recycling and impurity ingestion in the Translation, Confinement, and Sustainment--Upgrade (TCSU) device has allowed much higher plasma temperatures to be achieved in the field reversed configurations (FRC) under rotating magnetic field (RMF) formation and sustainment. The hotter plasmas have higher magnetic fields and much higher diamagnetic electron rotation rates so that the important ratio of average electron rotation frequency to RMF frequency, called {zeta}, approaches unity, for the first time, in TCSU. A large fraction of the RMF power is absorbed by an as yet unexplained (anomalous) mechanism directly proportional to the square of the RMF magnitude. It becomes of relatively lesser significance as the FRC current increases, and simple resistive heating begins to dominate, but the anomalous absorption is useful for initial plasma heating. Measurements of total absorbed power, and comparisons of applied RMF torque to torque on the electrons due to electron-ion friction under high-{zeta} operation, over a range of temperatures and fields, have allowed the separation of the classical Ohmic and anomalous heating to be inferred, and cross-field plasma resistivities to be calculated.

  16. Effects of background neutral particles on a field-reversed configuration plasma in the translation process

    SciTech Connect (OSTI)

    Matsuzawa, Yoshiki; Asai, Tomohiko; Takahashi, Tsutomu; Takahashi, Toshiki

    2008-08-15

    A field-reversed configuration (FRC) plasma was translated into a weakly ionized plasma and the effects of heating and particle buildup of the FRC plasma due to the background neutral particles and plasma injection in the translation process were investigated. Improvement of the particle and poloidal flux confinements and delay of onset of n=2 rotational instability were observed in the translation process. It was found that the internal structure of the plasma pressure (plasma temperature and density) at the separatrix and field null was deformed by the particle injection. FRC plasma translation through the background particles was equivalent to an end-on particle beam injection to the FRC plasma. Particles and energy were supplied during the translation. The results obtained for the phenomena of particle supply and plasma heating were also supported by the results of two-dimensional particle simulation. The effects of background particle injection appear to be a promising process for the regeneration of translation kinetic energy to plasma internal energy.

  17. Numerical Study of Field-reversed Configurations: The Formation and Ion Spin-up

    SciTech Connect (OSTI)

    E.V. Belova; R.C. Davidson; H. Ji; M. Yamada; C.D. Cothran; M.R. Brown; M.J. Schaffer

    2005-06-06

    Results of three-dimensional numerical simulations of field-reversed configurations (FRCs) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs, and the new FRC formation method by counter-helicity spheromak merging. Kinetic simulations show nonlinear saturation of the n = 1 tilt mode, where n is the toroidal mode number. The n = 2 and n = 3 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to the ion spin-up in the toroidal direction. The ion toroidal spin-up is shown to be related to the resistive decay of the internal flux, and the resulting loss of particle confinement. Three-dimensional MHD simulations of counter-helicity spheromak merging and FRC formation show good qualitative agreement with results from the SSX-FRC experiment. The simulations show formation of an FRC in about 20-30 Alfven times for typical experimental parameters. The growth rate of the n = 1 tilt mode is shown to be significantly reduced compared to the MHD growth rate due to the large plasma viscosity and field-line-tying effects.

  18. Penetration and radial force balance in field-reversed configuration with large rotating magnetic field

    SciTech Connect (OSTI)

    Ohnishi, M.; Fukuhara, M.; Masaki, T.; Osawa, H.; Chikano, T.; Hugrass, W.

    2008-10-15

    A field-reversed configuration (FRC) is formed by applying a rotating magnetic field (RMF) much larger than the axial magnetic field to a cylindrical glass vacuum chamber filled with 10 Pa argon gas without a preionization. The FRC with the plasma density 2.2x10{sup 19} m{sup -3}, the temperature 8.0 eV, the separatrix length 0.45 m, and the separatrix radius 0.035 m is sustained for the notably long period of 40 ms. It is observed that the antenna current which produces the RMF is reduced by about half after the FRC is formed. The interaction between the plasma and the antenna circuit increases the antenna resistance and changes the inductance of the antenna so that the circuit becomes nonresonant. The RMF is sufficiently large to fully penetrate to the center during the period and drive the current with a rigid rotor profile. The RMF is shown to play a major role in sustaining the plasma pressure.

  19. Flux generation and sustainment of a field reversed configuration with rotating magnetic field current drive

    SciTech Connect (OSTI)

    Slough, J. T.; Miller, K. E.

    2000-05-01

    A new experimental device has been constructed to study the flux build-up and sustainment of a field reversed configuration (FRC) with a rotating magnetic field (RMF). Even though complete penetration was expected from RMF theory, the RMF field was observed to penetrate only a few centimeters inside the FRC separatrix. Despite the limited penetration, significantly larger toroidal currents (40 kA) were driven than in previous experiments ({approx}2 kA) with the same RMF field. The high currents and lack of deep penetration allowed the axial field to be the dominant field throughout the FRC. The radially inward pondermotive force arising from axial screening currents at the FRC edge had a significant influence on energy and particle confinement, reducing convective losses to the limit of observability. With only ohmic heating, the measured low ion temperatures (2 eV) left the ions unmagnetized while the electrons ({approx}40 eV) were well magnetized. No destructive instability was observed for the RMF driven FRC despite the lack of a strong kinetic ion component. (c) 2000 American Institute of Physics.

  20. Magnetic design calculation and FRC formation modeling for the field reversed experiment liner

    SciTech Connect (OSTI)

    Dorf, L. A.; Intrator, T. P.; Renneke, R.; Hsu, S. C.; Wurden, G. A.; Awe, T.; Siemon, R.; Semenov, V. E.

    2008-10-01

    Integrated magnetic modeling and design are important to meet the requirements for (1) formation, (2) translation, and (3) compression of a field reversed configuration (FRC) for magnetized target fusion. Off-the-shelf solutions do not exist for many generic design issues. A predictive capability for time-dependent magnetic diffusion in realistically complicated geometry is essential in designing the experiment. An eddy-current code was developed and used to compute the mutual inductances between driven magnetic coils and passive magnetic shields (flux excluder plates) to calculate the self-consistent axisymmetric magnetic fields during the first two stages. The plasma in the formation stage was modeled as an immobile solid cylinder with selectable constant resistivity and magnetic flux that was free to readjust itself. It was concluded that (1) use of experimentally obtained anomalously large plasma resistivity in magnetic diffusion simulations is sufficient to predict magnetic reconnection and FRC formation, (2) comparison of predicted and experimentally observed timescales for FRC Ohmic decay shows good agreement, and (3) for the typical range of resistivities, the magnetic null radius decay rate scales linearly with resistivity. The last result can be used to predict the rate of change in magnetic flux outside of the separatrix (equal to the back-emf loop voltage), and thus estimate a minimum {theta}-coil loop voltage required to form an FRC.

  1. Kinetic Effects on the Stability Properties of Field-reversed Configurations: II. Nonlinear Evolution

    SciTech Connect (OSTI)

    Elena V. Belova; Ronald C. Davidson; Hantao Ji; Masaaki Yamada

    2003-11-25

    Results of three-dimensional hybrid simulations of the field-reversed configuration (FRC) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs. A wide range of ''bar s'' values is considered, where the ''bar s'' is the FRC kinetic parameter, which measures the number of ion gyroradii in the configuration. The linear and nonlinear stability of MHD modes with toroidal mode numbers n greater than or equal to 1 is investigated, including the effects of ion rotation, finite electron pressure, and weak toroidal field. Low-''bar s'' simulations show nonlinear saturation of the n = 1 tilt mode. The n greater than or equal to 2 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to ion spin-up in the toroidal direction. Large-''bar s'' simulations show no saturation of the tilt mode, and there is a slow nonlinear evolution of the instability after the initial fast linear growth. Overall, the hybrid simulations demonstrate the importance of nonlinear effects, which are responsible for the saturation of instabilities in low-''bar s'' configurations, and also for the increase in FRC life-time compared to MHD models in high-''bar s'' configurations.

  2. REVERSAL OF FORTUNE: INCREASED STAR FORMATION EFFICIENCIES IN THE EARLY HISTORIES OF DWARF GALAXIES?

    SciTech Connect (OSTI)

    Madau, Piero; Weisz, Daniel R.; Conroy, Charlie

    2014-08-01

    On dwarf galaxy scales, the different shapes of the galaxy stellar mass function and the dark halo mass function require a star-formation efficiency (SFE) in these systems that is currently more than 1 dex lower than that of Milky Way-size halos. Here, we argue that this trend may actually be reversed at high redshift. Specifically, by combining the resolved star-formation histories of nearby isolated dwarfs with the simulated mass-growth rates of dark matter halos, we show that the assembly of these systems occurs in two phases: (1) an early, fast halo accretion phase with a rapidly deepening potential well, characterized by a high SFE; and (2) a late, slow halo accretion phase where, perhaps as a consequence of reionization, the SFE is low. Nearby dwarfs have more old stars than predicted by assuming a constant or decreasing SFE with redshift, a behavior that appears to deviate qualitatively from the trends seen among more massive systems. Taken at face value, the data suggest that at sufficiently early epochs, dwarf galaxy halos above the atomic cooling mass limit can be among the most efficient sites of star formation in the universe.

  3. Electrolytic conditioning of a magnesium aluminum chloride complex for reversible magnesium deposition

    SciTech Connect (OSTI)

    Barile, Christopher J.; Barile, Elizabeth C.; Zavadil, Kevin R.; Nuzzo, Ralph G.; Gewirth, Andrew A.

    2014-12-04

    We describe in this report the electrochemistry of Mg deposition and dissolution from the magnesium aluminum chloride complex (MACC). The results define the requirements for reversible Mg deposition and definitively establish that voltammetric cycling of the electrolyte significantly alters its composition and performance. Elemental analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (SEM-EDS) results demonstrate that irreversible Mg and Al deposits form during early cycles. Electrospray ionization-mass spectrometry (ESI-MS) data show that inhibitory oligomers develop in THF-based solutions. These oligomers form via the well-established mechanism of a cationic ring-opening polymerization of THF during the initial synthesis of the MACC and under resting conditions. In contrast, MACC solutions in 1,2-dimethoxyethane (DME), an acyclic solvent, do not evolve as dramatically at open circuit potential. Furthermore, we propose a mechanism describing how the conditioning process of the MACC in THF improves its performance by both tuning the Mg:Al stoichiometry and eliminating oligomers.

  4. Highly Reversible Mg Insertion in Nanostructured Bi for Mg Ion Batteries

    SciTech Connect (OSTI)

    Shao, Yuyan; Gu, Meng; Li, Xiaolin; Nie, Zimin; Zuo, Pengjian; Li, Guosheng; Liu, Tianbiao L.; Xiao, Jie; Cheng, Yingwen; Wang, Chong M.; Zhang, Jiguang; Liu, Jun

    2014-01-08

    Rechargeable magnesium batteries have attracted wide attention for energy storage. Currently, most studies focus on Mg metal as the anode, but this approach is still limited by the properties of the electrolyte and poor control of the Mg plating/stripping processes.1,2 Here we report the synthesis and application of Bi nanotubes as a high performance anode material for rechargeable Mg ion batteries. The nanostructured Bi anode delivers a high reversible specific capacity (350 mAh/gBi, or 3430 mAh/cm3 Bi), excellent stability, and high columbic efficiency (95 % initial and very close to 100% afterwards). The good performance is attributed to the unique properties of in-situ formed, interconnected nanoporous bismuth. Such nanostructures can effectively accommodate the large volume change without losing electric contact and significantly reduce diffusion length for Mg2+. Significantly, the nanostructured Bi anode can be used with conventional electrolytes which will open new opportunities to study Mg ion battery chemistry and further improve the properties. The performance and the stability of a full cell Mg ion battery have been demonstrated with conventional electrolytes. This work suggests that other high energy density alloy compounds may also be considered for Mg-ion chemistry for high capacity electrode materials.

  5. Conventional empirical law reverses in the phase transitions of 122-type iron-based superconductors

    SciTech Connect (OSTI)

    Yu, Zhenhai; Wang, Lin; Wang, Luhong; Liu, Haozhe; Zhao, Jinggeng; Li, Chunyu; Sinogeikin, Stanislav; Wu, Wei; Luo, Jianlin; Wang, Nanlin; Yang, Ke; Zhao, Yusheng; Mao, Ho -kwang

    2014-11-24

    Phase transition of solid-state materials is a fundamental research topic in condensed matter physics, materials science and geophysics. It has been well accepted and widely proven that isostructural compounds containing different cations undergo same pressure-induced phase transitions but at progressively lower pressures as the cation radii increases. However, we discovered that this conventional law reverses in the structural transitions in 122-type iron-based superconductors. In this report, a combined low temperature and high pressure X-ray diffraction (XRD) measurement has identified the phase transition curves among the tetragonal (T), orthorhombic (O) and the collapsed-tetragonal (cT) phases in the structural phase diagram of the iron-based superconductor AFe2As2 (A = Ca, Sr, Eu, and Ba). As a result, the cation radii dependence of the phase transition pressure (T ? cT) shows an opposite trend in which the compounds with larger ambient radii cations have a higher transition pressure.

  6. Reversible Electrochemical Insertion of Lithium into Type I Ba8AlySi46-y Clathrate

    SciTech Connect (OSTI)

    Li, Ying; Raghavan, Rahul; Wagner, Nicholas; Davidowski, Stephen; Baggetto, Loic; Zhao, Ran; Cheng, Qian; Holland, Gregory p; Yarger, Jeffery L; Veith, Gabriel M; Ellis-Terrell, Carol; Miller, Michael A; Chan, Kwai; Chan, Candace

    2015-01-01

    Silicon clathrates contain cage-like structures that can encapsulate various guest atoms or molecules. Here we present an electrochemical evaluation of type I silicon clathrates based on Ba8AlySi46-y for the anode material in lithium-ion batteries. Post-cycling characterization with NMR and XRD show no discernible structural or volume changes even after electrochemical insertion of 44 Li into the clathrate structure. The observed properties are in stark contrast with lithiation of other silicon anodes, which become amorphous and suffer from larger volume changes. The lithiation/delithiation processes are proposed to occur in single phase reactions at approximately 0.2 and 0.4 V vs. Li/Li+, respectively, distinct from other diamond cubic or amorphous silicon anodes. Reversible capacities as high as 499 mAh g-1 at a 5 mA g-1 rate were observed for silicon clathrate with composition Ba8Al8.54Si37.46, corresponding to Li:Si of 1.18:1. The results show that silicon clathrates could be promising durable anodes for lithium-ion batteries.

  7. Liver fibrosis in mice induced by carbon tetrachloride and its reversion by luteolin

    SciTech Connect (OSTI)

    Domitrovic, Robert; Jakovac, Hrvoje; Tomac, Jelena; Sain, Ivana

    2009-12-15

    Hepatic fibrosis is effusive wound healing process in which excessive connective tissue builds up in the liver. Because specific treatments to stop progressive fibrosis of the liver are not available, we have investigated the effects of luteolin on carbon tetrachloride (CCl{sub 4})-induced hepatic fibrosis. Male Balb/C mice were treated with CCl{sub 4} (0.4 ml/kg) intraperitoneally (i.p.), twice a week for 6 weeks. Luteolin was administered i.p. once daily for next 2 weeks, in doses of 10, 25, and 50 mg/kg of body weight. The CCl{sub 4} control group has been observed for spontaneous reversion of fibrosis. CCl{sub 4}-intoxication increased serum aminotransferase and alkaline phosphatase levels and disturbed hepatic antioxidative status. Most of these parameters were spontaneously normalized in the CCl{sub 4} control group, although the progression of liver fibrosis was observed histologically. Luteolin treatment has increased hepatic matrix metalloproteinase-9 levels and metallothionein (MT) I/II expression, eliminated fibrinous deposits and restored architecture of the liver in a dose-dependent manner. Concomitantly, the expression of glial fibrillary acidic protein and alpha-smooth muscle actin indicated deactivation of hepatic stellate cells. Our results suggest the therapeutic effects of luteolin on CCl{sub 4}-induced liver fibrosis by promoting extracellular matrix degradation in the fibrotic liver tissue and the strong enhancement of hepatic regenerative capability, with MTs as a critical mediator of liver regeneration.

  8. Closeout Report - Search for Time Reversal Symmetry Violation with TREK at J-PARC

    SciTech Connect (OSTI)

    Kohl, Michael

    2015-04-15

    This DOE Early Career Award has enabled Dr. Michael Kohl to take on and expand his leadership roles in several projects such as TREK@J-PARC, OLYMPUS@DESY, MUSE@PSI, and in the experimental program in Hall C at Jefferson Lab. Dr. Kohl has successfully accomplished several items: (i) Preliminary results from SANE (E08-003) at Jefferson Lab: Former HU graduate student Anusha Liyanage has pursued her PhD research on SANE. Her analysis of the elastic ep scattering data has resulted in the extraction of the proton electric-to-magnetic form factor ratio from double spin asymmetries at the highest momentum transfer to date. The results are almost final and a publication is in preparation. (ii) Approval of TREK/E36 for running, preparation of simulation and analysis: the TREK experiment has been stage-II approved in fall 2013, has been mounted on the hall floor from November 2014 to April 2015, has been commissioned in April-June 2015 and is scheduled to run in fall 2015. The group has contributed significantly with simulations and magnetic field map calculations, has investigated the sensitivity of TREK to new light neutral particles, and contributed substantially to the mounting and commissioning of the experiment. (iii) Running of OLYMPUS and analysis: Under Dr. Kohl's leadership as spokesman, the OLYMPUS experiment has completed data taking beginning of 2013; calibrations and analysis have been well underway, with results to be expected in the course of 2015. (iv) Operation of GEM detectors at OLYMPUS and MUSE: The GEM telescopes built for OLYMPUS luminosity monitoring with forward-angle ep elastic scattering have been operated successfully, have meanwhile been relocated to PSI, and have been re-commissioned as beam particle trackers for the PSI secondary beams for MUSE. (v) Trained and prepared postdocs and graduate students for their future careers. Two postdocs from Dr. Kohl's group (Dr. Juergen Diefenbach and Dr. Peter Monaghan) have found permanent academic positions. Two former graduate students of the group have graduated and received their PhD degrees in nuclear physics (Dr. Anusha Liyanage and Dr. Ozgur Ates). In particular, this award has enabled Dr. Kohl to pursue the TREK project (Time Reversal Experiment with Kaons) at J-PARC, which he has been leading and advancing as International Spokesperson. Originally proposed as a search for time reversal symmetry violation [6], the project has evolved into a precision test of lepton flavor universality in the Standard Model along with sensitive searches for physics beyond the Standard Model through a possible discovery of new particles such as a sterile neutrino or a neutral gauge boson from the hidden sector in the mass region up to 300 MeV/c2 [7]. Experiment TREK/E36, first proposed in 2010, has been mounted between November 2014 and April 2015, and commissioning with beam has been started in April 2015, with production running anticipated in early summer and late fall 2015. It uses the apparatus from the previous KEK/E-246 experiment with partial upgrades to measure the ratio of decay widths of leptonic two-body decays of the charged kaon to µν and eν, respectively, which is highly sensitive to the ratio of electromagnetic charged lepton couplings and possible new physics processes that could differentiate between μ and e, hence breaking lepton flavor universality of the Standard Model. Through the searches for neutral massive particles, TREK/E36 can severely constrain any new physics scenarios designed to explain the proton radius puzzle [12, 13].

  9. New Pathways and Metrics for Enhanced, Reversible Hydrogen Storage in Boron-Doped Carbon Nanospaces

    SciTech Connect (OSTI)

    Pfeifer, Peter; Wexler, Carlos; Hawthorne, M. Frederick; Lee, Mark W.; Jalistegi, Satish S.

    2014-08-14

    This project, since its start in 2007entitled Networks of boron-doped carbon nanopores for low-pressure reversible hydrogen storage (2007-10) and New pathways and metrics for enhanced, reversible hydrogen storage in boron-doped carbon nanospaces (2010-13)is in support of the DOE's National Hydrogen Storage Project, as part of the DOE Hydrogen and Fuel Cells Programs comprehensive efforts to enable the widespread commercialization of hydrogen and fuel cell technologies in diverse sectors of the economy. Hydrogen storage is widely recognized as a critical enabling technology for the successful commercialization and market acceptance of hydrogen powered vehicles. Storing sufficient hydrogen on board a wide range of vehicle platforms, at energy densities comparable to gasoline, without compromising passenger or cargo space, remains an outstanding technical challenge. Of the main three thrust areas in 2007metal hydrides, chemical hydrogen storage, and sorption-based hydrogen storagesorption-based storage, i.e., storage of molecular hydrogen by adsorption on high-surface-area materials (carbons, metal-organic frameworks, and other porous organic networks), has emerged as the most promising path toward achieving the 2017 DOE storage targets of 0.055 kg H2/kg system (5.5 wt%) and 0.040 kg H2/liter system. The objective of the project is to develop high-surface-area carbon materials that are boron-doped by incorporation of boron into the carbon lattice at the outset, i.e., during the synthesis of the material. The rationale for boron-doping is the prediction that boron atoms in carbon will raise the binding energy of hydro- gen from 4-5 kJ/mol on the undoped surface to 10-14 kJ/mol on a doped surface, and accordingly the hydro- gen storage capacity of the material. The mechanism for the increase in binding energy is electron donation from H2 to electron-deficient B atoms, in the form of sp2 boron-carbon bonds. Our team is proud to have demonstrated the predicted increase in binding energy experimentally, currently at ~10 kJ/mol. The synthetic route for incorporation of boron at the outset is to create appropriately designed copoly- mers, with a boron-free and a boron-carrying monomer, followed by pyrolysis of the polymer, yielding a bo- ron-substituted carbon scaffold in which boron atoms are bonded to carbon atoms by synthesis. This is in contrast to a second route (funded by DE-FG36-08GO18142) in which first high-surface area carbon is cre- ated and doped by surface vapor deposition of boron, with incorporation of the boron into the lattice the final step of the fabrication. The challenge in the first route is to create high surface areas without compromising sp2 boron-carbon bonds. The challenge in the second route is to create sp2 boron-carbon bonds without com- promising high surface areas.

  10. Observations of improved confinement in field reversed configurations sustained by antisymmetric rotating magnetic fields

    SciTech Connect (OSTI)

    Guo, H.Y.; Hoffman, A.L.; Steinhauer, L.C.

    2005-06-15

    Rotating magnetic fields (RMF) have been employed to both form and sustain currents in field reversed configurations (FRC). A major concern about this method has been the fear of opening up magnetic field lines with even small ratios of vacuum RMF B{sub {omega}} to external confinement field B{sub e}. A recently proposed innovation was to use an antisymmetric arrangement of RMF, but vacuum calculations with full RMF penetration showed that very low values of B{sub {omega}}/B{sub e} would still be required to provide field-line closure. Recent comparisons of symmetric and antisymmetric RMF drive on the translation, confinement, and sustainment (TCS) facility [A. L. Hoffman, H. Y. Guo, J. T. Slough et al., Fusion Sci. Technol. 41, 92 (2002)] have shown strong improvements in the basic confinement properties of the FRCs when using antisymmetric drive, even with ratios of B{sub {omega}}/B{sub e} as high as 0.3. This is due to normal standard operation with only partial penetration of the RMF beyond the FRC separatrix. The uniform transverse RMF in vacuum is shielded by the conducting plasma, resulting in a mostly azimuthal field near the FRC separatrix with a very small radial component. Simple numerical calculations using analytical solutions for the partially penetrated antisymmetric RMF, superimposed on Grad-Shafranov solutions for the poloidal FRC fields, show good field-line closure for the TCS experimental conditions. The antisymmetric arrangement also leads to more efficient current drive and improved stabilization of rotational modes.

  11. On the reversal of star formation rate-density relation at z = 1: Insights from simulations

    SciTech Connect (OSTI)

    Tonnesen, Stephanie; Cen, Renyue E-mail: cen@astro.princeton.edu

    2014-06-20

    Recent surveys have found a reversal of the star formation rate (SFR)-density relation at z = 1 from that at z = 0, while the sign of the slope of the color-density relation remains unchanged. We use adaptive mesh refinement cosmological hydrodynamic simulations of a 21 24 20 h {sup 3} Mpc{sup 3} region to examine the SFR-density and color-density relations of galaxies at z = 0 and z = 1. The local environmental density is defined by the dark matter mass in spheres of radius 1 h {sup 1} Mpc, and we probe two decades of environmental densities. Our simulations produce a large increase of SFR with density at z = 1, as in the Elbaz et al. observations. We also find a significant evolution to z = 0, where the SFR-density relation is much flatter. The simulated color-density relation is consistent from z = 1 to z = 0, in agreement with observations. We find that the increase in SFR with local density at z = 1 is due to a growing population of star-forming galaxies in higher-density environments. At z = 0 and z = 1 both the SFR and cold gas mass are correlated with the galaxy halo mass, and therefore the correlation between median halo mass and local density is an important cause of the SFR-density relation at both redshifts. However, at z = 0 the local density on 1 h {sup 1} Mpc scales affects galaxy SFRs as much as halo mass. Finally, we find indications that while at z = 0 high-density environments depress galaxy SFRs, at z = 1 high-density environments tend to increase SFRs.

  12. pH effect on the separation of uranium fluoride effluents by the reverse osmosis process

    SciTech Connect (OSTI)

    Yun Chen ); Min-Lin Chu; Mu-Chang Shieh , Lung-tan, )

    1992-04-01

    Ammonium fluoride solutions and uranium fluoride effluents (UFE) with solute concentrations from 0.101 to 7,920 kg/m{sup 3}, at pH 2.80 to 9.60, have been treated with a continuous feedback reverse osmosis (RO) process. The solute rejections of NH{sub 4}{sup +}, F{sup {minus}}, and U{sup 6+} depend heavily on the feed pH value. For ammonium fluoride solutions, the rejection ratio of NH{sub 4}{sup +} decreases sharply from ca. 90 to 44.2% with the feed pH increased from 3.30 to 9.60, while that of F{sup {minus}} increases abruptly from 44.8 to 99.9% at the same pH change. For UFE solutions, the rejection ratio of U{sup 6+} remains greater than 90% at pH 2.80-7.13, while that of F{sup {minus}} decreases steadily from 96.4 to 18.8% with decreasing feed pH. Accordingly, the fluoride ions can be separated from UFE solutions under acidic conditions. The changes of solute rejection with feed pH can be explained by the different solubilities of the solutes in the membrane at different pH values. The UFE solutions with {alpha} and {beta} activities at 20.4-53.7 and 8.99-21.3 ({times} 10{sup 5} Baq/m{sup 3}) can be reduced to a level lower than 2.41 and 3.37 ({times}10{sup 5} Baq/m{sup 3}), respectively, by the current RO process.

  13. Field reversing magnetotail current sheets: earth, Venus, and Comet Giacobini-Zinner

    SciTech Connect (OSTI)

    McComas, D.J.

    1986-09-01

    This dissertation examines the field reversing magnetotail current sheets at the earth, Venus, and Comet Giacobini-Zinner. In the near earth study a new analysis technique is developed to calculate the detailed current density distributions within the cross tail current sheet for the first time. This technique removes the effects of a variable sheet velocity by inverting intersatellite timings between the co-orbiting satellites ISEE-1 and -2. Case studies of three relatively geomagnetically quiet crossings are made; sheet thicknesses and peak current densities are approx.1-5 x 10/sup 4/ km and approx.5-50 nA/m/sup 2/. Current density distributions reveal a high density central region, lower density shoulders, and considerable fine structure throughout. In the Venus study another new analysis technique is developed to reconstruct the average tail configuration from a correlation between field magnitude and draping angle in a large statistical data set. In the comet study, high resolution magnetic field and plasma electron data from the ICE traversal of Giacobini-Zinner are combined for the first time to determine the tail/current sheet geometry and calculate certain important but unmeasured local ion and upstream properties. Pressure balance across the tail gives ion temperatures and betas of approx.1.2 x 10/sup 5/ K and approx.40 in the center of the current sheet to approx.1 x 10/sup 6/ K and approx.3 in the outer lobes. Axial stress balance shows that the velocity shear upstream near the nucleus is >6 (approx.1 at ICE), and that a region of strongly enhanced mass loading (ion source rate approx.24 times that upstream from lobes) exists upstream from the current sheet. The integrated downtail mass flux is approx.2.6 x 10/sup 26/ H/sub 2/O+/sec, which is only approx.1% of the independently determined total cometary efflux. 79 refs., 37 figs.

  14. Energetic-particle-driven instabilities and induced fast-ion transport in a reversed field pinch

    SciTech Connect (OSTI)

    Lin, L.; Brower, D. L.; Ding, W. X.; Anderson, J. K.; Capecchi, W.; Eilerman, S.; Forest, C. B.; Koliner, J. J.; Nornberg, M. D.; Reusch, J.; Sarff, J. S.; Liu, D.

    2014-05-15

    Multiple bursty energetic-particle (EP) driven modes with fishbone-like structure are observed during 1?MW tangential neutral-beam injection in a reversed field pinch (RFP) device. The distinguishing features of the RFP, including large magnetic shear (tending to add stability) and weak toroidal magnetic field (leading to stronger drive), provide a complementary environment to tokamak and stellarator configurations for exploring basic understanding of EP instabilities. Detailed measurements of the EP mode characteristics and temporal-spatial dynamics reveal their influence on fast ion transport. Density fluctuations exhibit a dynamically evolving, inboard-outboard asymmetric spatial structure that peaks in the core where fast ions reside. The measured mode frequencies are close to the computed shear Alfvn frequency, a feature consistent with continuum modes destabilized by strong drive. The frequency pattern of the dominant mode depends on the fast-ion species. Multiple frequencies occur with deuterium fast ions compared to single frequency for hydrogen fast ions. Furthermore, as the safety factor (q) decreases, the toroidal mode number of the dominant EP mode transits from n=5 to n=6 while retaining the same poloidal mode number m=1. The transition occurs when the m=1, n=5 wave-particle resonance condition cannot be satisfied as the fast-ion safety factor (q{sub fi}) decreases. The fast-ion temporal dynamics, measured by a neutral particle analyzer, resemble a classical predator-prey relaxation oscillation. It contains a slow-growth phase arising from the beam fueling followed by a rapid drop when the EP modes peak, indicating that the fluctuation-induced transport maintains a stiff fast-ion density profile. The inferred transport rate is strongly enhanced with the onset of multiple EP modes.

  15. The TITAN Reversed-Field Pinch fusion reactor study: Scoping phase report

    SciTech Connect (OSTI)

    Not Available

    1987-01-01

    The TITAN research program is a multi-institutional effort to determine the potential of the Reversed-Field Pinch (RFP) magnetic fusion concept as a compact, high-power-density, and ''attractive'' fusion energy system from economic (cost of electricity, COE), environmental, and operational viewpoints. In particular, a high neutron wall loading design (18 MW/m/sup 2/) has been chosen as the reference case in order to quantify the issue of engineering practicality, to determine the physics requirements and plasma operating mode, to assess significant benefits of compact systems, and to illuminate the main drawbacks. The program has been divided into two phases, each roughly one year in length: the Scoping Phase and the Design Phase. During the scoping phase, the TITAN design team has defined the parameter space for a high mass power density (MPD) RFP reactor, and explored a variety of approaches to the design of major subsystems. Two major design approaches consistent with high MPD and low COE, the lithium-vanadium blanket design and aqueous loop-in-pool design, have been selected for more detailed engineering evaluation in the design phase. The program has retained a balance in its approach to investigating high MPD systems. On the one hand, parametric investigations of both subsystems and overall system performance are carried out. On the other hand, more detailed analysis and engineering design and integration are performed, appropriate to determining the technical feasibility of the high MPD approach to RFP fusion reactors. This report describes the work of the scoping phase activities of the TITAN program. A synopsis of the principal technical findings and a brief description of the TITAN multiple-design approach is given. The individual chapters on Plasma Physics and Engineering, Parameter Systems Studies, Divertor, Reactor Engineering, and Fusion Power Core Engineering have been cataloged separately.

  16. Use of InSpector{sup TM} 1 1000 Instrument with LaBr{sub 3} for Nuclear Criticality Safety (NCS) Applications at the Westinghouse Hematite Decommissioning Project (HDP) - 13132

    SciTech Connect (OSTI)

    Pritchard, Megan; Guido, Joe

    2013-07-01

    The Westinghouse Hematite Decommissioning Project (HDP) is a former nuclear fuel cycle facility that is currently undergoing decommissioning. One aspect of the decommissioning scope is remediation of buried nuclear waste in unlined burial pits. The current Nuclear Criticality Safety program relies on application of criticality controls based on radiological setpoints from a 2 x 2 Sodium Iodide (NaI) detector. Because of the nature of the material buried (Low Enriched Uranium (LEU), depleted uranium, thorium, and radium) and the stringent threshold for application of criticality controls based on waste management (0.1 g {sup 235}U/L), a better method for {sup 235}U identification and quantification has been developed. This paper outlines the early stages of a quick, in-field nuclear material assay and {sup 235}U mass estimation process currently being deployed at HDP. Nuclear material initially classified such that NCS controls are necessary can be demonstrated not to require such controls and dispositioned as desired by project operations. Using Monte Carlo techniques and a high resolution Lanthanum Bromide (LaBr) detector with portable Multi-Channel Analyzer (MCA), a bounding {sup 235}U mass is assigned to basic geometries of nuclear material as it is excavated. The deployment of these methods and techniques has saved large amounts of time and money in the nuclear material remediation process. (authors)

  17. Formation of a long-lived hot field reversed configuration by dynamically merging two colliding high-{beta} compact toroids

    SciTech Connect (OSTI)

    Guo, H. Y.; Binderbauer, M. W.; Barnes, D.; Putvinski, S.; Rostoker, N.; Sevier, L.; Tuszewski, M.; Anderson, M. G.; Andow, R.; Bonelli, L.; Brown, R.; Bui, D. Q.; Bystritskii, V.; Clary, R.; Cheung, A. H.; Conroy, K. D.; Deng, B. H.; Dettrick, S. A.; Douglass, J. D.; Feng, P.

    2011-05-15

    A high temperature field reversed configuration (FRC) has been produced in the newly built, world's largest compact toroid (CT) facility, C-2, by colliding and merging two high-{beta} CTs produced using the advanced field-reversed {theta}-pinch technology. This long-lived, stable merged state exhibits the following key properties: (1) apparent increase in the poloidal flux from the first pass to the final merged state, (2) significantly improved confinement compared to conventional {theta}-pinch FRCs with flux decay rates approaching classical values in some cases, (3) strong conversion from kinetic energy into thermal energy with total temperature (T{sub e} + T{sub i}) exceeding 0.5 keV, predominantly into the ion channel. Detailed modeling using a new 2-D resistive magnetohydrodynamic (MHD) code, LamyRidge, has demonstrated, for the first time, the formation, translation, and merging/reconnection dynamics of such extremely high-{beta} plasmas.

  18. Momentum transport in the vicinity of q{sub min} in reverse shear tokamaks due to ion temperature gradient turbulence

    SciTech Connect (OSTI)

    Singh, Rameswar; Laboratoire de Physique des Plasmas, Ecole Polytechnique route de Saclay, 91128 Palaiseau Cedex ; Singh, R; WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 ; Jhang, Hogun; Diamond, P. H.; Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093; Center for Astrophysics and Space Sciences, University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0424

    2014-01-15

    We present an analytic study of momentum transport of tokamak plasmas in the vicinity of minimum safety factor (q) position in reversed magnetic shear configuration. Slab ion temperature gradient modes with an equilibrium flow profile are considered in this study. Quasi-linear calculations of momentum flux clearly show the novel effects of q-curvature on the generation of intrinsic rotation and mean poloidal flow without invoking reflectional symmetry breaking of parallel wavenumber (k{sub ?}). This q-curvature effect originates from the inherent asymmetry in k{sub ?} populations with respect to a rational surface due to the quadratic proportionality of k{sub ?} when q-curvature is taken into account. Discussions are made of possible implications of q-curvature induced plasma flows on internal transport barrier formation in reversed shear tokamaks.

  19. Magnetic Interaction Reversal In Watermelon Nanostructured Cr-doped Fe Nanoclusters

    SciTech Connect (OSTI)

    Kaur, Maninder; Dai, Qilin; Bowden, Mark E.; Engelhard, Mark H.; Wu, Yaqiao; Tang, Jinke; Qiang, You

    2013-11-11

    Cr-doped core-shell Fe/Fe-oxide nanoclusters (NCs) were synthesized at varied atomic percentages of Cr from 0 at. % to 8 at. %. The low concentrations of Cr (<10 at. %) were selected in order to inhibit the complete conversion of the Fe-oxide shell to Cr2O3 and the Fe core to FeCr alloy. The magnetic interaction in Fe/Fe-oxide NCs (rv25 nm) can be controlled by antiferromagnetic Cr-dopant. We report the origin of r-FeCr phase at very low Cr concentration (2 at. %) unlike in previous studies, and the interaction reversal from dipolar to exchange interaction in watermelon-like Cr-doped core-shell NCs. The giant magnetoresistance (GMR) effect,1,2 where an antiferromagnetic (AFM) exchange coupling exists between two ferromagnetic (FM) layers separated by a certain type of magnetic or non-magnetic spacer,3 has significant potential for application in the magnetic recording industry. Soon after the discovery of the GMR, the magnetic properties of multilayer systems (FeCr) became a subject of intensive study. The application of bulk iron-chromium (Fe-Cr) alloys has been of great interest, as these alloys exhibit favorable prop- erties including corrosion resistance, high strength, hardness, low oxidation rate, and strength retention at elevated temper- ature. However, the structural and magnetic properties of Cr-doped Fe nanoclusters (NCs) have not been investigated in-depth. Of all NCs, Fe-based clusters have unique magnetic properties as well as favorable catalytic characteristics in reactivity, selectivity, and durability.4 The incorporation of dopant of varied type and concentration in Fe can modify its chemical ordering, thereby optimizing its electrical, optical, and magnetic properties and opening up many new applications. The substitution of an Fe atom (1.24 A˚ ) by a Cr atom (1.25 A˚ ) can easily modify the magnetic properties, since (i) the curie temperature (Tc ) of Fe is 1043 K, while Cr is an itinerant AFM with a bulk Neel temperature TN =311 K, and (ii) Fe and Cr share the same crystal structure (bcc) with only 0.5% difference between their lattice constants.

  20. Reversible Bending Fatigue Test System for Investigating Vibration Integrity of Spent Nuclear Fuel during Transportation

    SciTech Connect (OSTI)

    Wang, Jy-An John; Wang, Hong; Bevard, Bruce Balkcom; Howard, Rob L; Flanagan, Michelle

    2013-01-01

    Transportation packages for spent nuclear fuel (SNF) must meet safety requirements under normal and accident conditions as specified by federal regulations. During transportation, SNF experiences unique conditions and challenges to cladding integrity due to the vibrational and impact loading during road or rail shipment. Oak Ridge National Laboratory (ORNL) has been developing testing capabilities that can be used to improve the understanding of the impacts on SNF integrity due to vibration loading, especially for high burn-up SNF in normal transportation operation conditions. This information can be used to meet the nuclear industry and U.S. Nuclear Regulatory Commission needs in the area of safety and security of spent nuclear fuel storage and transport operations. The ORNL developed test system can perform reversible-bending fatigue testing to evaluate both the static and dynamic mechanical response of SNF rods under simulated loads. The testing apparatus is also designed to meet the challenges of hot-cell operation, including remote installation and detachment of the SNF test specimen, in-situ test specimen deformation measurement, and implementation of a driving system suitable for use in a hot cell. The system contains a U-frame set-up equipped with uniquely designed grip rigs, to protect SNF rod and to ensure valid test results, and use of 3 specially designed LVDTs to obtain the in-situ curvature measurement. A variety of surrogate test rods have been used to develop and calibrate the test system as well as in performing a series of systematic cyclic fatigue tests. The surrogate rods include stainless steel (SS) cladding, SS cladding with cast epoxy, and SS cladding with alumina pellets inserts simulating fuel pellets. Testing to date has shown that the interface bonding between the SS cladding and the alumina pellets has a significant impact on the bending response of the test rods as well as their fatigue strength. The failure behaviors observed from tested surrogate rods provides a fundamental understanding of the underlying failure mechanisms of the SNF surrogate rod under vibration which has not been achieved previously. The newly developed device is scheduled to be installed in the hot-cell in summer 2013 to test high burnup SNF.

  1. Comparison of Energy Efficiency and Power Density in Pressure Retarded Osmosis and Reverse Electrodialysis

    SciTech Connect (OSTI)

    Yip, NY; Elimelech, M

    2014-09-16

    Pressure retarded osmosis (PRO) and reverse electrodialysis (RED) are emerging membrane-based technologies that can convert chemical energy in salinity gradients to useful work. The two processes have intrinsically different working principles: controlled mixing in PRO is achieved by water permeation across salt-rejecting membranes, whereas RED is driven by ion flux across charged membranes. This study compares the energy efficiency and power density performance of PRO and RED with simulated technologically available membranes for natural, anthropogenic, and engineered salinity gradients (seawater-river water, desalination brine-wastewater, and synthetic hypersaline solutions, respectively). The analysis shows that PRO can achieve both greater efficiencies (54-56%) and higher power densities (2.4-38 W/m(2)) than RED (18-38% and 0.77-1.2 W/m(2)). The superior efficiency is attributed to the ability of PRO membranes to more effectively utilize the salinity difference to drive water permeation and better suppress the detrimental leakage of salts. On the other hand, the low conductivity of currently available ion exchange membranes impedes RED ion flux and, thus, constrains the power density. Both technologies exhibit a trade-off between efficiency and power density: employing more permeable but less selective membranes can enhance the power density, but undesired entropy production due to uncontrolled mixing increases and some efficiency is sacrificed. When the concentration difference is increased (i.e., natural -> anthropogenic -> engineered salinity gradients), PRO osmotic pressure difference rises proportionally but not so for RED Nernst potential, which has logarithmic dependence on the solution concentration. Because of this inherently different characteristic, RED is unable to take advantage of larger salinity gradients, whereas PRO power density is considerably enhanced. Additionally, high solution concentrations suppress the Donnan exclusion effect of the charged RED membranes, severely reducing the permselectivity and diminishing the energy conversion efficiency. This study indicates that PRO is more suitable to extract energy from a range of salinity gradients, while significant advancements in ion exchange membranes are likely necessary for RED to be competitive with PRO.

  2. A Remote Absorption Process for Disposal of Evaporate and Reverse Osmosis Concentrates

    SciTech Connect (OSTI)

    Brunsell, D.A.

    2008-07-01

    Many commercial nuclear plants and DOE facilities generate secondary waste streams consisting of evaporator bottoms and reverse osmosis (RO) concentrate. Since liquids are not permitted in disposal facilities, these waste streams must be converted to dry solids, either by evaporation to dried solids or by solidification to liquid-free solids. Evaporation of the liquid wastes reduces their volume, but requires costly energy and capital equipment. In some cases, concentration of the contaminants during drying can cause the waste to exceed Class A waste for nuclear utilities or exceed DOE transuranic limits. This means that disposal costs will be increased, or that, when the Barnwell, SC disposal site closes to waste outside of the Atlantic Compact in July 2008, the waste will be precluded from disposal for the foreseeable future). Solidification with cement agents requires less energy and equipment than drying, but results in a volume increase of 50-100%. The doubling or tripling of waste weight, along with the increased volume, sharply increases shipping and disposal costs. Confronted with these unattractive alternatives, Diversified Technologies Services (DTS), in conjunction with selected nuclear utilities and D and D operations at Rocky Flats, undertook an exploratory effort to convert this liquid wastewater to a solid without using cement. This would avoid the bulking effect of cement, and permit the waste to be disposed of the Energy Solutions facility in Utah as well as some DOE facilities. To address the need for an attractive alternative to drying and cement solidification, a test program was developed using a polymer absorbent media to convert the concentrate streams to a liquid-free waste form that meets the waste acceptance criteria of the pertinent burial sites. Two approaches for mixing the polymer with the liquid were tested: mechanical mixing and in-situ incorporation. As part of this test program, a process control program (PCP) was developed that is 100% scalable from a concentrate test sample as small as 50 grams to full-scale processing of 100 cubic foot containers or larger. In summary: The absorption process offers utilities a viable and less costly alternative to on-site drying or solidification of concentrates. The absorption process can be completed by site personnel or by a vendor as a turnkey service. The process is suitable for multiple types of waste, including RO and evaporator concentrates, sludges, and other difficult to process waters and wet solids. (author)

  3. Hysteretic behavior of Fe(phen){sub 2}(NCS){sub 2} spin-transition microparticles vs. the environment: A huge reversible component resolved by first order reversal curves

    SciTech Connect (OSTI)

    Tanasa, Radu; Stancu, Alexandru; Enachescu, Cristian; Laisney, Jérôme; Boillot, Marie-Laure

    2014-01-20

    We discuss the influence of the embedding matrix on the thermal hysteretic behavior of spin transition microparticles of Fe(phen){sub 2}(NCS){sub 2} by using a series of experimental first order reversal curves (FORCs). The shape of FORCs supports the hypothesis considering additional interactions between the spin-transition microparticles and the embedding matrix, which compares to a negative pressure on the particles. A mean-field approach based on negative variable external pressures, together with a cut off/switch on of particles-matrix interactions accounts for the experimental features.

  4. Magnetization reversal induced by in-plane current in Ta/CoFeB/MgO structures with perpendicular magnetic easy axis

    SciTech Connect (OSTI)

    Zhang, C.; Yamanouchi, M. Ikeda, S.; Sato, H.; Fukami, S.; Matsukura, F.; Ohno, H.

    2014-05-07

    We investigate in-plane current-induced magnetization reversal under an in-plane magnetic field in Hall bar shaped devices composed of Ta/CoFeB/MgO structures with perpendicular magnetic easy axis. The observed relationship between the directions of current and magnetization switching and Ta thickness dependence of magnetization switching current are accordance with those for magnetization reversal by spin transfer torque originated from the spin Hall effect in the Ta layer.

  5. Photo-controllable thermoelectric properties with reversibility and photo-thermoelectric effects of tungsten trioxide accompanied by its photochromic phenomenon

    SciTech Connect (OSTI)

    Azuma, Chiori; Kawano, Takuto; Kakemoto, Hirofumi; Irie, Hiroshi

    2014-11-07

    The addition of photo-controllable properties to tungsten trioxide (WO{sub 3}) is of interest for developing practical applications of WO{sub 3} as well as for interpreting such phenomena from scientific viewpoints. Here, a sputtered crystalline WO{sub 3} thin film generated thermoelectric power due to ultraviolet (UV) light-induced band-gap excitation and was accompanied by a photochromic reaction resulting from generating W{sup 5+} ions. The thermoelectric properties (electrical conductivity (?) and Seebeck coefficient (S)) and coloration of WO{sub 3} could be reversibly switched by alternating the external stimulus between UV light irradiation and dark storage. After irradiating the film with UV light, ? increased, whereas the absolute value of S decreased, and the photochromic (coloration) reaction was detected. Notably, the opposite behavior was exhibited by WO{sub 3} after dark storage, and this reversible cycle could be repeated at least three times. Moreover, photo-thermoelectric effects (photo-conductive effect (photo-conductivity, ?{sub photo}) and photo-Seebeck effect (photo-Seebeck coefficient, S{sub photo})) were also detected in response to visible-light irradiation of the colored WO{sub 3} thin films. Under visible-light irradiation, ?{sub photo} and the absolute value of S{sub photo} increased and decreased, respectively. These effects are likely attributable to the excitation of electrons from the mid-gap visible light absorption band (W{sup 5+} state) to the conduction band of WO{sub 3}. Our findings demonstrate that the simultaneous, reversible switching of multiple properties of WO{sub 3} thin film is achieved by the application of an external stimulus and that this material exhibits photo-thermoelectric effects when irradiated with visible-light.

  6. Improvement of dose distribution in breast radiotherapy using a reversible transverse magnetic field Linac-MR unit

    SciTech Connect (OSTI)

    Esmaeeli, A. D.; Mahdavi, S. R.; Pouladian, M.; Bagheri, S.; Monfared, A. S.

    2014-01-15

    Purpose: To investigate the improvement in dose distribution in tangential breast radiotherapy using a reversible transverse magnetic field that maintains the same direction of Lorentz force between two fields. The investigation has a potential application in future Linac-MR units. Methods: Computed tomography images of four patients and magnetic fields of 0.251.5 Tesla (T) were used for Monte Carlo simulation. Two patients had intact breast while the other two had mastectomy. Simulations of planning and chest wall irradiation were similar to the actual clinical process. The direction of superior-inferior magnetic field for the medial treatment beam was reversed for the lateral beam. Results: For the ipsilateral lung and heart mean doses were reduced by a mean (range) of 45.8% (27.6%58.6%) and 26.0% (20.2%38.9%), respectively, depending on various treatment plan setups. The mean V{sub 20} for ipsilateral lung was reduced by 55.0% (43.6%77.3%). In addition acceptable results were shown after simulation of 0.25 T magnetic field demonstrated in dose-volume reductions of the heart, ipsilateral lung, and noninvolved skin. Conclusions: Applying a reversible magnetic field during breast radiotherapy, not only reduces the dose to the lung and heart but also produces a sharp drop dose volume histogram for planning target volume, because of bending of the path of secondary charged particles toward the chest wall by the Lorentz force. The simulations have shown that use of the magnetic field at 1.5 T is not feasible for clinical applications due to the increase of ipsilateral chest wall skin dose in comparison to the conventional planning while 0.25 T is suitable for all patients due to dose reduction to the chest wall skin.

  7. Waste treatment by reverse osmosis and membrane processes: Industrial. (Latest citations from the EI compendex*plus database). Published Search

    SciTech Connect (OSTI)

    1995-09-01

    The bibliography contains citations concerning the use of membranes in the treatment of industrial wastewaters. Reverse osmosis, ion exchange, electrodialysis, liquid membranes, and ultrafiltration techniques are described. Wastewater treatments for removal of metals, ammonia, sodium compounds, nitrates, fluorides, dyes, biologicals, and radioactive waste using membrane technology are discussed. Applications of this technology to the chemical, petrochemical, pulp, textile, steel, ore treatment, electro-plating, and other wastewater and groundwater-remediation industries are included.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  8. Waste treatment by reverse osmosis and membrane processes: Industrial. (Latest citations from the Compendex database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1993-05-01

    The bibliography contains citations concerning the use of membranes in the treatment of industrial wastewaters. Reverse osmosis, ion exchange, electrodialysis, liquid membranes, and ultrafiltration techniques are described. Wastewater treatments for removal of metals, ammonia, sodium compounds, nitrates, fluorides, dyes, biologicals, and radioactive waste using membrane technology are discussed. Applications of this technology to the chemical, petrochemical, pulp, textile, steel, ore treatment, electro-plating, and other wastewater and groundwater-remediation industries are included. (Contains 250 citations and includes a subject term index and title list.)

  9. Waste treatment by reverse osmosis and membrane processes: Industrial. (Latest citations from the EI Compendex*Plus database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1993-12-01

    The bibliography contains citations concerning the use of membranes in the treatment of industrial wastewaters. Reverse osmosis, ion exchange, electrodialysis, liquid membranes, and ultrafiltration techniques are described. Wastewater treatments for removal of metals, ammonia, sodium compounds, nitrates, fluorides, dyes, biologicals, and radioactive waste using membrane technology are discussed. Applications of this technology to the chemical, petrochemical, pulp, textile, steel, ore treatment, electro-plating, and other wastewater and groundwater-remediation industries are included. (Contains 250 citations and includes a subject term index and title list.)

  10. Mitigation of rotational instability of high-beta field-reversed configuration by double-sided magnetized plasmoid injection

    SciTech Connect (OSTI)

    Itagaki, H.; Inomoto, M.; Asai, T.; Takahashi, Ts.

    2014-03-15

    Active control of destructive rotational instability in a high-beta field-reversed configuration (FRC) plasma was demonstrated by using double-sided plasmoid injection technique. The elliptical deformation of the FRC's cross section was mitigated as a result of substantial suppression of spontaneous spin-up by the plasmoid injection. It was found that the injected plasmoid provided better stability against the rotational mode, suggesting that the compensation of the FRC's decaying magnetic flux might help to suppress its spin-up.

  11. Onset and Saturation of Ion Heating by Odd-parity Rotating-magnetic-fields in a Field-reversed Configuration

    SciTech Connect (OSTI)

    A.S. Landsman, S.A. Cohen, A.H. Glasser

    2005-11-01

    Heating of figure-8 ions by odd-parity rotating magnetic fields (RMFο) applied to an elongated field-reversed configuration (FRC) is investigated. The largest energy gain occurs at resonances (s ≡ ω(sub)R/ω) of the RMFο frequency, ω(sub)R, with the figure-8 orbital frequency, ω, and is proportional to s^2 for s – even resonances and to s for s – odd resonances. The threshold for the transition from regular to stochastic orbits explains both the onset and saturation of heating. The FRC magnetic geometry lowers the threshold for heating below that in the tokamak by an order of magnitude.

  12. Issues in measure-preserving three dimensional flow integrators: Self-adjointness, reversibility, and non-uniform time stepping

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

    Finn, John M.

    2015-03-01

    Properties of integration schemes for solenoidal fields in three dimensions are studied, with a focus on integrating magnetic field lines in a plasma using adaptive time stepping. It is shown that implicit midpoint (IM) and a scheme we call three-dimensional leapfrog (LF) can do a good job (in the sense of preserving KAM tori) of integrating fields that are reversible, or (for LF) have a 'special divergence-free' property. We review the notion of a self-adjoint scheme, showing that such schemes are at least second order accurate and can always be formed by composing an arbitrary scheme with its adjoint. Wemore » also review the concept of reversibility, showing that a reversible but not exactly volume-preserving scheme can lead to a fractal invariant measure in a chaotic region, although this property may not often be observable. We also show numerical results indicating that the IM and LF schemes can fail to preserve KAM tori when the reversibility property (and the SDF property for LF) of the field is broken. We discuss extensions to measure preserving flows, the integration of magnetic field lines in a plasma and the integration of rays for several plasma waves. The main new result of this paper relates to non-uniform time stepping for volume-preserving flows. We investigate two potential schemes, both based on the general method of Ref. [11], in which the flow is integrated in split time steps, each Hamiltonian in two dimensions. The first scheme is an extension of the method of extended phase space, a well-proven method of symplectic integration with non-uniform time steps. This method is found not to work, and an explanation is given. The second method investigated is a method based on transformation to canonical variables for the two split-step Hamiltonian systems. This method, which is related to the method of non-canonical generating functions of Ref. [35], appears to work very well.« less

  13. Impurity transport studies in the Madison Symmetric Torus reversed-field pinch during standard and pulsed poloidal current drive regimes

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

    mdnornberg IP Address: 128.104.165.161 This content was downloaded on 16/05/2014 at 16:16 Please note that terms and conditions apply. Impurity transport studies in the Madison Symmetric Torus reversed-field pinch during standard and pulsed poloidal current drive regimes View the table of contents for this issue, or go to the journal homepage for more 2014 Plasma Phys. Control. Fusion 56 075012 (http://iopscience.iop.org/0741-3335/56/7/075012) Home Search Collections Journals About Contact us My

  14. Effect of martensite to austenite reversion on the formation of nano/submicron grained AISI 301 stainless steel

    SciTech Connect (OSTI)

    Karimi, M.; Najafizadeh, A.; Kermanpur, A.; Eskandari, M.

    2009-11-15

    The martensite to austenite reversion behavior of 90% cold rolled AISI 301 stainless steel was investigated in order to refine the grain size. Cold rolled specimens were annealed at 600-900 deg. C, and subsequently characterized by scanning electron microscopy, X-ray diffraction, Feritscope, and hardness measurements. The effects of annealing parameters on the formation of fully-austenitic nano/submicron grained structure and the mechanisms involved were studied. It was found that annealing at 800 deg. C for 10 s exhibited the smallest average austenite grain size of 240 {+-} 60 nm with an almost fully-austenitic structure.

  15. Atomic-resolution study of polarity reversal in GaSb grown on Si by scanning transmission electron microscopy

    SciTech Connect (OSTI)

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

    2012-11-01

    The atomic-resolved reversal of the polarity across an antiphase boundary (APB) was observed in GaSb films grown on Si by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The investigation of the interface structure at the origin of the APB reveals that coalescence of two domains with Ga-prelayer and Sb-prelayer causes the sublattice reversal. The local strain and lattice rotation distributions of the APB, attributed to the discordant bonding length at the APB with the surrounding GaSb lattice, were further studied using the geometric phase analysis technique. The crystallographic characteristics of the APBs and their interaction with other planar defects were observed with HAADF-STEM. The quantitative agreement between experimental and simulated images confirms the observed polarities in the acquired HAADF-STEM data. The self-annihilation mechanism of the APBs is addressed based on the rotation induced by anti-site bonds and APBs' faceting.

  16. On the relationships between Michaelis–Menten kinetics, reverse Michaelis–Menten kinetics, Equilibrium Chemistry Approximation kinetics and quadratic kinetics

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

    Tang, J. Y.

    2015-09-03

    The Michaelis–Menten kinetics and the reverse Michaelis–Menten kinetics are two popular mathematical formulations used in many land biogeochemical models to describe how microbes and plants would respond to changes in substrate abundance. However, the criteria of when to use which of the two are often ambiguous. Here I show that these two kinetics are special approximations to the Equilibrium Chemistry Approximation kinetics, which is the first order approximation to the quadratic kinetics that solves the equation of enzyme-substrate complex exactly for a single enzyme single substrate biogeochemical reaction with the law of mass action and the assumption of quasi-steady-state formore » the enzyme-substrate complex and that the product genesis from enzyme-substrate complex is much slower than the equilibration between enzyme-substrate complexes, substrates and enzymes. In particular, I showed that the derivation of the Michaelis–Menten kinetics does not consider the mass balance constraint of the substrate, and the reverse Michaelis–Menten kinetics does not consider the mass balance constraint of the enzyme, whereas both of these constraints are taken into account in the Equilibrium Chemistry Approximation kinetics. By benchmarking against predictions from the quadratic kinetics for a wide range of substrate and enzyme concentrations, the Michaelis–Menten kinetics was found to persistently under-predict the normalized sensitivity ∂ ln v / ∂ ln k2+ of the reaction velocity v with respect to the maximum product genesis rate k2+, persistently over-predict the normalized sensitivity ∂ ln v / ∂ ln k1+ of v with respect to the intrinsic substrate affinity k1+, persistently over-predict the normalized sensitivity ∂ ln v / ∂ ln [ E ]T of v with respect the total enzyme concentration [ E ]T and persistently under-predict the normalized sensitivity ∂ ln v / ∂ ln [ S ]T of v with respect to the total substrate concentration [ S ]T. Meanwhile, the reverse Michaelis–Menten kinetics persistently under-predicts ∂ ln v / ∂ ln k2+ and ∂ ln v / ∂ ln [ E ]T, and persistently over-predicts ∂ ln v / ∂ ln k1+ and ∂ ln v / ∂ ln [ S ]T. In contrast, the Equilibrium Chemistry Approximation kinetics always gives consistent predictions of ∂ ln v / ∂ ln k2+, ∂ ln v / ∂ ln k1+, ∂ ln v / ∂ ln [ E ]T and ∂ ln v / ∂ ln [ S ]T. Since the Equilibrium Chemistry Approximation kinetics includes the advantages from both the Michaelis–Menten kinetics and the reverse Michaelis–Menten kinetics and it is applicable for almost the whole range of substrate and enzyme abundances, soil biogeochemical modelers therefore no longer need to choose when to use the Michaelis–Menten kinetics or the reverse Michaelis–Menten kinetics. I expect removing this choice ambiguity will make it easier to formulate more robust and consistent land biogeochemical models.« less

  17. Cycle Evaluations of Reversible Chemical Reactions for Solar Thermochemical Energy Storage in Support of Concentrating Solar Power Generation Systems

    SciTech Connect (OSTI)

    Krishnan, Shankar; Palo, Daniel R.; Wegeng, Robert S.

    2010-07-25

    The production and storage of thermochemical energy is a possible route to increase capacity factors and reduce the Levelized Cost of Electricity from concentrated solar power generation systems. In this paper, we present the results of cycle evaluations for various thermochemical cycles, including a well-documented ammonia closed-cycle along with open- and closed-cycle versions of hydrocarbon chemical reactions. Among the available reversible hydrocarbon chemical reactions, catalytic reforming-methanation cycles are considered; specifically, various methane-steam reforming cycles are compared to the ammonia cycle. In some cases, the production of an intermediate chemical, methanol, is also included with some benefit being realized. The best case, based on overall power generation efficiency and overall plant capacity factor, was found to be an open cycle including methane-steam reforming, using concentrated solar energy to increase the chemical energy content of the reacting stream, followed by combustion to generate heat for the heat engine.

  18. Observation of tilting activities in translated field reversed configuration plasma using computer tomography at two different cross sections

    SciTech Connect (OSTI)

    Yoshimura, Satoru; Sugimoto, Satoshi; Okada, Shigefumi

    2007-11-15

    Tilting activities of field reversed configuration (FRC) plasma were observed in translation experiments using computer tomography (CT) at two different cross sections in the FRC injection experiment (FIX) machine [S. Okada et al., Nucl. Fusion 47, 677 (2007)]. In these experiments, two sets of CT devices were installed at the upstream and downstream sides of the confinement chamber of the FIX. Each CT device was composed of three arrays of detectors sensitive to the near-infrared radiation. The peak of the reconstructed emission profile at one side was displaced from the center of the cross section of the chamber. On the other hand, the reconstructed profile at the other side was located around the center. This result suggests that the FRC plasma was tilting in the axial direction. The occurrence of the observed tilting activities had almost no effect on the lifetime of the FRC plasma.

  19. Onset and Saturation of Ion Heating by Odd-Parity Rotating Magnetic Fields in a Field-Reversed Configuration

    SciTech Connect (OSTI)

    Landsman, A.S.; Cohen, S.A.; Glasser, A.H.

    2006-01-13

    Heating of figure-8 orbit ions by odd-parity rotating magnetic fields (RMF{sub o}) applied to an elongated field-reversed configuration (FRC) is investigated. The largest energy gain occurs at resonances (s{identical_to}{omega}{sub R}/{omega}) of the RMF{sub o} frequency, {omega}{sub R}, with the figure-8 orbital frequency, {omega}, and is proportional to s{sup 2} for s-even resonances and to s for s-odd resonances. The threshold for the transition from regular to stochastic orbits explains both the onset and saturation of heating. The FRC magnetic geometry lowers the threshold for heating below that in the tokamak by an order of magnitude.

  20. Experimental and numerical study of mixed convection with flow reversal in coaxial double-duct heat exchangers

    SciTech Connect (OSTI)

    Mare, Thierry; Voicu, Ionut; Miriel, Jacques [Laboratoire de Genie Civil et de Genie Mecanique (LGCGM), INSA de Rennes, IUT Saint Malo, 35043 Rennes (France); Galanis, Nicolas [Faculte de genie, Universite de Sherbrooke, Sherbrooke, QC (Canada); Sow, Ousmane [Laboratoire d'Energie Appliquee, Ecole superieure Polytechnique, Dakar (Senegal)

    2008-04-15

    Velocity vectors in a vertical coaxial double-duct heat exchanger for parallel ascending flow of water under conditions of laminar mixed convection have been determined experimentally using the particle image velocimetry technique. The measured velocity distributions for large annular flow rates, resulting in an essentially isothermal environment for the stream in the inner tube, are in very good agreement with corresponding numerical predictions. For flow rates of the same order of magnitude in the inner tube and the annulus, and corresponding temperature differences of about 20 C, experimental observations show that flow reversal occurs simultaneously in both streams over large axial distances for both heating and cooling of the flow in the inner tube. (author)

  1. Reversible Poisoning of the Nickel/Zirconia Solid Oxide Fuel Cell Anodes by Hydrogen Chloride in Coal Gas

    SciTech Connect (OSTI)

    Marina, Olga A.; Pederson, Larry R.; Thomsen, Edwin C.; Coyle, Christopher A.; Yoon, Kyung J.

    2010-10-15

    The performance of anode-supported solid oxide fuel cells (SOFC) was evaluated in synthetic coal gas containing HCl in the temperature range 650 to 850oC. Exposure to up to 800 ppm HCl resulted in reversible poisoning of the Ni/zirconia anode by chlorine species adsorption, the magnitude of which decreased with increased temperature. Performance losses increased with the concentration of HCl to ~100 ppm, above which losses were insensitive to HCl concentration. Cell voltage had no effect on poisoning. No evidence was found for long-term degradation that can be attributed to HCl exposure. Similarly, no evidence of microstructural changes or formation of new solid phases as a result of HCl exposure was found. From thermodynamic calculations, solid nickel chloride phase formation was shown to be highly unlikely in coal gas. Further, the presence of HCl at even the highest anticipated concentrations in coal gas would minimally increase the volatility of nickel.

  2. A library of MiMICs allows tagging of genes and reversible, spatial and temporal knockdown of proteins in Drosophila

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

    Nagarkar-Jaiswal, Sonal; Lee, Pei-Tseng; Campbell, Megan E.; Chen, Kuchuan; Anguiano-Zarate, Stephanie; Cantu Gutierrez, Manuel; Busby, Theodore; Lin, Wen-Wen; He, Yuchun; Schulze, Karen L.; et al

    2015-03-31

    Here, we document a collection of ~7434 MiMIC (Minos Mediated Integration Cassette) insertions of which 2854 are inserted in coding introns. They allowed us to create a library of 400 GFP-tagged genes. We show that 72% of internally tagged proteins are functional, and that more than 90% can be imaged in unfixed tissues. Moreover, the tagged mRNAs can be knocked down by RNAi against GFP (iGFPi), and the tagged proteins can be efficiently knocked down by deGradFP technology. The phenotypes associated with RNA and protein knockdown typically correspond to severe loss of function or null mutant phenotypes. Finally, we demonstratemore » reversible, spatial, and temporal knockdown of tagged proteins in larvae and adult flies. This new strategy and collection of strains allows unprecedented in vivo manipulations in flies for many genes. These strategies will likely extend to vertebrates.« less

  3. Assessment of oil-pretreatment technologies to improve performance of reverse-osmosis systems. Technical literature review and technologies evaluation

    SciTech Connect (OSTI)

    Tansel, B.; Villate, J.

    1992-06-19

    The services provided under this contract include both theoretical and experimental research for development of an appropriate technology for treatment of petroleum hydrocarbons in source water for reverse osmosis (RO) systems. This report evaluates and screens the candidate technologies identified during the literature review in accordance with the approved Technology Evaluation Plan. A short-list of technologies that warrant further study is recommended to be carried forward to the experimental phase. The contamination problems due to petroleum hydrocarbons have been long recognized. However, the treatment technologies available for treatment of petroleum contaminated media are still very limited. Major limitations relative to treatment of petroleum hydrocarbons include: exact chemical composition is not defined; aerobic treatment processes are not effective for breaking down heavy petroleum hydrocarbons; anaerobic treatment processes are slow; and physical/chemical treatment processes are expensive and there is usually additional waste produced during treatment of the contaminated media.

  4. Leptin upregulates telomerase activity and transcription of human telomerase reverse transcriptase in MCF-7 breast cancer cells

    SciTech Connect (OSTI)

    Ren, He; Zhao, Tiansuo; Wang, Xiuchao; Gao, Chuntao; Wang, Jian; Yu, Ming; Hao, Jihui

    2010-03-26

    The aim was to analyze the mechanism of leptin-induced activity of telomerase in MCF-7 breast cancer cells. We found that leptin activated telomerase in a dose-dependent manner; leptin upregulated the expression of Human Telomerase Reverse Transcriptase (hTERT) at mRNA and protein levels; blockade of signal transducer and activator of transcription 3 (STAT3) phosphorylation significantly counteracted leptin-induced hTERT transcription and protein expression; chromatin immunoprecipitation analysis showed that leptin enhanced the binding of STAT3 to the hTERT promoter. This study uncovers a new mechanism of the proliferative effect of leptin on breast cancer cells and provides a new explanation of obesity-related breast cancer.

  5. Surveillance for Western equine encephalitis St. Louis encephalitis and West Nile viruses using reverse transcription loop-mediated isothermal amplification

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

    Meagher, Robert J.; Ball, Cameron Scott; Langevin, Stanley A.; Fang, Ying; Wheeler, Sarah S.; Coffey, Lark L.

    2016-01-25

    In this study, collection of mosquitoes and testing for vector-borne viruses is a key surveillance activity that directly influences the vector control efforts of public health agencies, including determining when and where to apply insecticides. Vector control districts in California routinely monitor for three human pathogenic viruses including West Nile virus (WNV), Western equine encephalitis virus (WEEV), and St. Louis encephalitis virus (SLEV). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) offers highly sensitive and specific detection of these three viruses in a single multiplex reaction, but this technique requires costly, specialized equipment that is generally only available in centralized publicmore » health laboratories. We report the use of reverse transcription loop-mediated isothermal amplification (RT-LAMP) to detect WNV, WEEV, and SLEV RNA extracted from pooled mosquito samples collected in California, including novel primer sets for specific detection of WEEV and SLEV, targeting the nonstructural protein 4 (nsP4) gene of WEEV and the 3’ untranslated region (3’-UTR) of SLEV. Our WEEV and SLEV RT-LAMP primers allowed detection of <0.1 PFU/reaction of their respective targets in <30 minutes, and exhibited high specificity without cross reactivity when tested against a panel of alphaviruses and flaviviruses. Furthermore, the SLEV primers do not cross-react with WNV, despite both viruses being closely related members of the Japanese encephalitis virus complex. The SLEV and WEEV primers can also be combined in a single RT-LAMP reaction, with discrimination between amplicons by melt curve analysis. Although RT-qPCR is approximately one order of magnitude more sensitive than RT-LAMP for all three targets, the RT-LAMP technique is less instrumentally intensive than RT-qPCR and provides a more cost-effective method of vector-borne virus surveillance.« less

  6. Enhancement of Br ( B d ? ? + ? - ) / Br ( B s ? ? + ? - ) in supersymmetric unified models

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

    Dutta, Bhaskar; Mimura, Yukihiro

    2015-05-14

    We explain the 2.3? deviation in the recent measurements of the neutral B meson decays into muon pairs from the standard model prediction in the framework of supersymmetric grand unified models using antisymmetric coupling as a new source of flavor violation. We show a correlation between the Bd????? decay and the CP phase in the Bd?J/?K decay and that their deviations from the standard model predictions can be explained after satisfying constraints arising from various hadronic and leptonic rare decay processes, B-B, K-K oscillation data, and electric dipole moments of electron and neutron. The allowed parameter space is typically representedmoreby pseudoscalar Higgs mass mA?1 TeV and tan?H(?vu/vd)?20 for squark and gluino masses around 2 TeV.less

  7. BR UFF BIG PINEY WILD ROSE BLU E GAP BR UFF UNIT WAMSUT TER

    Gasoline and Diesel Fuel Update (EIA)

    BOE Reserve Class No 2001 reserves 0.1 - 10 MBOE 10.1 - 100 MBOE 100.1 - 1,000 MBOE 1,000.1 - 10,000 MBOE 10,000.1 - 100,000 MBOE > 100,000 MBOE Basin Outline ID The mapped oil and gas field boundary outlines were created by the Reserves and Production Division, Office of Oil and Gas, Energy Information Administration pursuant to studies required by Section 604 of the Energy Policy and Conservation Act Amendments of 2000 (P.L. 106-469). The boundaries are not informed by subsurface structural

  8. BR UFF BIG PINEY WILD ROSE BLU E GAP BR UFF UNIT WAMSUT TER

    Gasoline and Diesel Fuel Update (EIA)

    Gas Reserve Class No 2001 gas reserves 0.1 - 10 MMCF 10.1 - 100 MMCF 100.1 - 1,000 MMCF 1,000.1 - 10,000 MMCF 10,000.1 - 100,000 MMCF > 100,000 MMCF Basin Outline ID The mapped oil and gas field boundary outlines were created by the Reserves and Production Division, Office of Oil and Gas, Energy Information Administration pursuant to studies required by Section 604 of the Energy Policy and Conservation Act Amendments of 2000 (P.L. 106-469). The boundaries are not informed by subsurface

  9. BR UFF BIG PINEY WILD ROSE BLU E GAP BR UFF UNIT WAMSUT TER

    Gasoline and Diesel Fuel Update (EIA)

    Liquids Reserve Class No 2001 liquids reserves 0.1 - 10 Mbbl 10.1 - 100 Mbbl 100.1 - 1,000 Mbbl 1,000.1 - 10,000 Mbbl 10,000.1 - 100,000 Mbbl Basin Outline ID The mapped oil and gas field boundary outlines were created by the Reserves and Production Division, Office of Oil and Gas, Energy Information Administration pursuant to studies required by Section 604 of the Energy Policy and Conservation Act Amendments of 2000 (P.L. 106-469). The boundaries are not informed by subsurface structural

  10. Hanford Speakers Bureau<br><br>Frequently Asked Questions - Hanford Site

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

    Speakers Bureau Hanford Speakers Bureau Frequently Asked Questions Hanford Speakers Bureau Hanford Speakers Bureau Request Form Hanford Speakers Bureau Frequently Asked Questions Why Hanford? Video Hanford Speakers Bureau Presentations FY2015 Hanford Speakers Bureau Presentations FY2014 Hanford Speakers Bureau Presentations FY2013 Hanford Site Tours Hanford Speakers Bureau Frequently Asked Questions Email Email Page | Print Print Page |Text Increase Font Size Decrease Font Size What is Hanford?

  11. Mechanism of Thermal Reversal of the (Fulvalene)tetracarbonyldiruthenium Photoisomerization: Toward Molecular Solar-Thermal Energy Storage

    SciTech Connect (OSTI)

    Kanai, Y; Srinivasan, V; Meier, S K; Vollhardt, K P; Grossman, J C

    2010-02-18

    In the currently intensifying quest to harness solar energy for the powering of our planet, most efforts are centered around photoinduced generic charge separation, such as in photovoltaics, water splitting, other small molecule activation, and biologically inspired photosynthetic systems. In contrast, direct collection of heat from sunlight has received much less diversified attention, its bulk devoted to the development of concentrating solar thermal power plants, in which mirrors are used to focus the sun beam on an appropriate heat transfer material. An attractive alternative strategy would be to trap solar energy in the form of chemical bonds, ideally through the photoconversion of a suitable molecule to a higher energy isomer, which, in turn, would release the stored energy by thermal reversal. Such a system would encompass the essential elements of a rechargeable heat battery, with its inherent advantages of storage, transportability, and use on demand. The underlying concept has been explored extensively with organic molecules (such as the norbornadiene-quadricyclane cycle), often in the context of developing photoswitches. On the other hand, organometallic complexes have remained relatively obscure in this capacity, despite a number of advantages, including expanded structural tunability and generally favorable electronic absorption regimes. A highly promising organometallic system is the previously reported, robust photo-thermal fulvalene (Fv) diruthenium couple 1 {l_reversible} 2 (Scheme 1). However, although reversible and moderately efficient, lack of a full, detailed atom-scale understanding of its key conversion and storage mechanisms have limited our ability to improve on its performance or identify optimal variants, such as substituents on the Fv, ligands other than CO, and alternative metals. Here we present a theoretical investigation, in conjunction with corroborating experiments, of the mechanism for the heat releasing step of 2 {yields} 1 and its Fe (4) and Os (6) relatives. The results of the combined study has enabled a rigorous interpretation of earlier and new experimental measurements and paint a surprising picture. First-principles calculations were employed based on spin unrestricted density functional theory (DFT) with a non-empirical gradient corrected exchange-correlation functional. Ultrasoft pseudopotentials were used to describe the valence-core interactions of electrons, including scalar relativistic effects of the core. Wavefunctions and charge densities were expanded in plane waves with kinetic energies up to 25 and 200 Rydberg, respectively. Reaction pathways were delineated with the string method, as implemented within the Car-Parrinello approach. This method allows for the efficient determination of the minimum energy path (MEP) of atomistic transitions and thus also saddle points (transition states, TSs), which are the energy maxima along the MEP. All geometries were optimized until all forces on the atoms were less than 0.02 eV/{angstrom}. The calculated structures of 1 and 2 were in good agreement with their experimental counterparts.

  12. Final Report: DE- FC36-05GO15063, Fundamental Studies of Advanced High-Capacity, Reversible Metal Hydrides

    SciTech Connect (OSTI)

    Jensen, Craig; McGrady, Sean; Severa, Godwin; Eliseo, Jennifer; Chong, Marina

    2015-02-08

    The project was component of the US DOE, Metal Hydride Center of Excellence (MHCoE). The Sandia National Laboratory led center was established to conduct highly collaborative and multi-disciplinary applied R&D to develop new reversible hydrogen storage materials that meet or exceed DOE/FreedomCAR 2010 and 2015 system targets for hydrogen storage materials. Our approach entailed a wide variety of activities ranging from synthesis, characterization, and evaluation of new candidate hydrogen storage materials; screening of catalysts for high capacity materials requiring kinetics enhancement; development of low temperature methods for nano-confinement of hydrides and determining its effects on the kinetics and thermodynamics of hydrides; and development of novel processes for the direct re-hydrogenation of materials. These efforts have resulted in several advancements the development of hydrogen storage materials. We have greatly extended the fundamental knowledge about the highly promising hydrogen storage carrier, alane (AlH?), by carrying out the first crystal structure determinations and the first determination of the heats of dehydrogenation of ?AlH? and ?-AlD?. A low-temperature homogenous organometallic approach to incorporation of Al and Mg based hydrides into carbon aerogels has been developed that that allows high loadings without degradation of the nano-porous scaffold. Nano-confinement was found to significantly improve the dehydrogenation kinetics but not effect the enthalpy of dehydrogenation. We conceived, characterized, and synthesized a novel class of potential hydrogen storage materials, bimetallic borohydrides. These novel compounds were found to have many favorable properties including release of significant amounts of hydrogen at moderate temperatures (75-190C). However, in situ IR studies in tandem with thermal gravimetric analysis have shown that about 0.5 equivalents of diborane are released during the dehydrogenation making re-hydrogenation effectively impossible and precluding these compounds from further consideration as hydrogen storage materials. The hydrogen cycling of >11 wt % between MgB? to Mg(BH?)? was achieved but required very forcing conditions. Under moderate conditions (dehydrogenation 200C; re-hydrogenation 250C, 120 atm H2), Mg(BH?)? undergoes reversible dehydrogenation to Mg(B3H8)2. Although the 2.5 wt% cycling capacity does not meet current on-board storage targets, this result provides first example of direct hydrogen cycling of a borohydride under moderate conditions and demonstrates the plausibility of finding mild, PEM fuel cell relevant conditions for the high capacity, reversible dehydrogenation of borohydrides. A method was developed for the room temperature, direct hydrogenation of Ti-doped LiH/Al in liquefied dimethyl ether under 100 atm of H?. The process has been optimized such that Ti-doped LiAlH? is obtained in >95% yield. The WTT energy efficiency our direct synthesis process has been estimated to approach the 60% U.S. DOE target. Thus our simplification of the hydrogenation half-cycle may provide the key to harnessing the long-recognized potential of this lightweight, high capacity material as a practical hydrogen carrier. Finally, we have gained insight into the fundamental basis of the enhanced hydrogen cycling kinetics of Ti-doped NaAlH? through studies by solid state H NMR, anelastic spectroscopy; muon spin rotation; and positron annihilation.

  13. Influence of cationic substitutions on the first charge and reversible capacities of lithium-rich layered oxide cathodes

    SciTech Connect (OSTI)

    Wang, Chih-Chieh; Manthiram, Arumugam

    2013-06-24

    The reversible capacity values of lithium-rich layered oxide cathodes depend on the length (capacity) of the plateau region during the first charge. With an aim to understand the factors that control the length of the plateau region and thereby enhance the reversible capacity, the effects of various cationic substitutions in Li1.2Mn0.6Ni0.2O2 have been investigated systematically. Specifically, substitutions of (i) M3+ = Al3+, Cr3+, Fe3+, Co3+, and Ga3+ for equal amounts of Mn4+and Ni2+ in Li1.2Mn0.6-0.5xNi0.2-0.5xMxO2 with x = 0.06, 0.13, and 0.2, (ii) Ti4+ for Mn4+ in Li1.2Mn0.6-xTixNi0.2O2 with x = 0.025, 0.05, and 0.1, and (iii) Mg2+ for Ni2+ in Li1.2Mn0.6Ni0.2-xMgxO2 with x = 0.025, 0.05, and 0.1 have been investigated. The cationic substitutions affect the first charge capacity values both in the sloping region corresponding to the oxidation of the transition-metal ions to the 4+ state and in the plateau region corresponding to the oxidation of O2- ions to O2 and/or transition-metal ions beyond 4+, which control the reversible capacity values in subsequent cycles. While the changes in the sloping-region capacity could be readily understood by considering the redox activities of the transition-metal ions, the plateau-region capacity is found to depend sensitively on the metaloxygen covalence, which is dictated by the relative positions of the metal:3d band with respect to the top of the O2-:2p band, and electron delocalization. For instance, an overlap of the Co3+/4+:t2g band with the top of the O2-:2p band along with a partially filled t 2g band across the shared octahedral edges makes the oxygen loss from the lattice and/or oxidation beyond 4+ much more facile.

  14. Multiple temperature-induced magnetization reversals in SmCr{sub 1−x}Fe{sub x}O{sub 3} system

    SciTech Connect (OSTI)

    Yin, L.H.; Liu, Y.; Tan, S.G.; Zhao, B.C.; Dai, J.M.; Song, W.H.; Sun, Y.P.

    2013-10-15

    Graphical abstract: - Highlights: • Multiple temperature-induced magnetization reversals were observed in x = 0.1. • Coexistence of normal and inverse magnetocaloric effects was observed. • A reasonable model was proposed to explain the magnetization reversals. - Abstract: The structural and magnetic properties of the SmCr{sub 1−x}Fe{sub x}O{sub 3} (0 ≤ x ≤ 0.5) system have been investigated. Multiple temperature-induced magnetization reversals were observed in x = 0.1. The high-temperature magnetization reversal is due to the special spin structure, in which the net canted moment of the Cr-rich regions and the net moment of the Fe–Cr ordered regions orient in opposite direction; while the low temperature one can be ascribed to the spin reorientation. The sample with x = 0.5 exhibits the highest compensation temperature. Coexistence of normal and inverse magnetocaloric effects was observed in all doped samples. Potential applications in magnetic refrigeration based constant temperature bath near room temperature (∼286 K) have been demonstrated.

  15. Characterization of nanostructured zirconia prepared by hydrolysis and reverse micelle synthesis by small-angle neutron and X-ray scattering

    SciTech Connect (OSTI)

    Thiyagarajan, P.; Li, X.; Littrell, K.; Seifert, S.; Csencsits, R.; Loong, C.

    1999-12-07

    Low temperature techniques such as hydrolysis and reverse micelle syntheses provide the opportunity to determine the relationship between the structural properties and preparation conditions of zirconia powders as well as to tailor their physicochemical properties. The authors have performed small-angle neutron and synchrotron X-ray scattering (SANS and SAXS) experiments to study the nucleation and organization of zirconia nanoparticles via different preparation routes. First, the formation of reverse micelles in individual and mixed solutions of (ZrOCl{sub 2}+D{sub 2}O)/AOT/C{sub 6}D{sub 5}CD{sub 3}, and (NH{sub 4}OH+H{sub 2}O)/AOT/C{sub 6}D{sub 5}CD{sub 3} systems at water/AOT molar ratio of 20 was characterized. Second, the aggregation of zirconia gels obtained from the reaction of the reverse micelle solutions after heat treatments was studied. Third, the nanostructure of zirconia powders prepared by the reverse micelle method is compared with the corresponding powders prepared by hydrolysis after different heat treatments.

  16. Investigation and Demonstration of Dry Carbon-Based Sorbent Injection for Mercury Control

    SciTech Connect (OSTI)

    Jason Ruhl; Justin Smith; Sharon Sjostrom; Sheila Haythorthwaite; Terry Hunt

    1997-08-01

    The U.S. Department of Energy (DOE) issued Public Service Company of Colorado (PSCO) a cost sharing contract to evaluate carbon-based sorbents for mercury control on a 600 acfm laboratory-scale particulate control module (PCM). The PCM can be configured as simulate an electrostatic precipitator, a pulse-jet fabric filter, or a reverse-gas fabric filter and is installed on an operating coal-fired power plant. Three different dry carbon-based sorbents were tested this quarter to determine their mercury removal capability in the different configurations. The project is currently in the seventh quarter of an eight-quarter Phase I project. Testing in all configurations is nearly complete. Original plans included the use of an on-line mercury analyzer to collect test data. However, due to very low baseline mercury concentration, on-line measurement did not provide accurate data. The project used a modified MESA method grab sample technique to determine inlet and outlet mercury concentrations. A major concern during sorbent evaluations was the natural ability of the flyash at the test site to remove mercury. This often made determination of sorbent only mercury removal difficult. The PCM was configured as a reverse-gas baghouse and brought online with "clean" flue gas on March 10* at an A/C of 2.0 ft/min. The dustcake forms the filtering media in a reverse gas baghouse. In the absence of flyash, the bags were precoated with a commercially available alumina silicate material to form an inert dustcake. Some baseline tests were completed with clean gas for comparison to clean gas pulse jet tests. The PCM was reconfigured as a TOXECON unit in April 1997 with testing completed in May 1997. TOXECON, an EPIU patented technology, is a pulse-jet baghouse operating at a high A/C ratio downstream of a primary particulate colIector with sorbent injection upstream of the baghouse for air toxics removal. Mercury removals of O to 97o/0 were obtained depending on test conditions.

  17. Room-temperature ionic liquid-amine solutions: tunable solvents for efficient and reversible capture of CO{sub 2}

    SciTech Connect (OSTI)

    Dean Camper; Jason E. Bara; Douglas L. Gin; Richard D. Noble

    2008-11-05

    Solutions of room-temperature ionic liquids (RTILs) and commercially available amines were found to be effective for the capture of CO{sub 2} as carbamate salts. RTIL solutions containing 50 mol % (16% v/v) monoethanolamine (MEA) are capable of rapid and reversible capture of 1 mol of CO{sub 2} per 2 moles MEA to give an insoluble MEA-carbamate precipitate that helps to drive the capture reaction (as opposed to aqueous amine systems). Diethanolamine (DEA) can also be used in the same manner for CO{sub 2} capture in RTILs containing a pendant hydroxyl group. The captured CO{sub 2} in the resulting RTIL-carbamate salt mixtures can be readily released by either heating and/or subjecting them to reduced pressure. Using this unprecedented and industrially attractive mixing approach, the desirable properties of RTILs (i.e., nonvolatility, enhancedCO{sub 2} solubility, lower heat capacities) can be combined with the performance of amines for CO{sub 2} capture without the use of specially designed, functionalized 'task-specific' ionic liquids. By mixing RTILs with commercial amines, reactive solvents with a wide range of amine loading levels can be tailored to capture CO{sub 2} in a variety of conditions and processes. These RTIL-amine solutions behave similarly to their water-based counterparts but may offer many advantages, including increased energy efficiency, compared to current aqueous amine technologies.

  18. Kinetic effects on double hysteresis in spin crossover molecular magnets analyzed with first order reversal curve diagram technique

    SciTech Connect (OSTI)

    Stan, Raluca-Maria; Gaina, Roxana; Enachescu, Cristian E-mail: radu.tanasa@uaic.ro; Stancu, Alexandru; Tanasa, Radu E-mail: radu.tanasa@uaic.ro; Bronisz, Robert

    2015-05-07

    In this paper, we analyze two types of hysteresis in spin crossover molecular magnets compounds in the framework of the First Order Reversal Curve (FORC) method. The switching between the two stable states in these compounds is accompanied by hysteresis phenomena if the intermolecular interactions are higher than a threshold. We have measured the static thermal hysteresis (TH) and the kinetic light induced thermal hysteresis (LITH) major loops and FORCs for the polycrystalline Fe(II) spin crossover compound [Fe{sub 1?x}Zn{sub x}(bbtr){sub 3}](ClO{sub 4}){sub 2} (bbtr?=?1,4-di(1,2,3-triazol-1-yl)butane), either in a pure state (x?=?0) or doped with Zn ions (x?=?0.33) considering different sweeping rates. Here, we use this method not only to infer the domains distribution but also to disentangle between kinetic and static components of the LITH and to estimate the changes in the intermolecular interactions introduced by dopants. We also determined the qualitative relationship between FORC distributions measured for TH and LITH.

  19. Reversible nano-structuring of SrCrO3-? through oxidization and reduction at low temperatures

    SciTech Connect (OSTI)

    Zhang, Hongliang; Sushko, Petr; Colby, Robert J.; Du, Yingge; Bowden, Mark E.; Chambers, Scott A.

    2014-08-18

    Oxygen vacancies are often present in complex oxides as point defects and their effect on the electronic properties of the oxides is typically uniform and isotropic. Exploiting oxygen deficiency in order to generate controllably, novel structures and functional properties remains a challenging goal. We show that epitaxial strontium chromite films can be transformed, reversibly and at low temperature, from the cubic metallic perovskite SrCrO3-? to the rhombohedral semiconducting SrCrO2.8. Oxygen vacancies aggregate and give rise to ordered arrays of {111}-oriented SrO2 planes interleaved between layers of tetrahedrally-coordinated Cr4+ and separated by ~1 nm. First-principle calculations provide insight into the origin of the stability of such nanostructures and, consistent with the experimental data, predict that the barrier for oxide ion diffusion along these quasi-2D nanostructures is ~5 times lower than that in the cubic SrCrO3-? a property of considerable importance in, for example, solid oxide fuel cells.

  20. Probe measurements of the three-dimensional magnetic field structure in a rotating magnetic field sustained field-reversed configuration

    SciTech Connect (OSTI)

    Velas, K. M.; Milroy, R. D.

    2014-01-15

    A translatable three-axis probe was constructed and installed on the translation, confinement, and sustainment upgrade (TCSU) experiment. With ninety windings, the probe can simultaneously measure B{sub r}, B{sub θ}, and B{sub z} at 30 radial positions, and can be placed at any desired axial position within the field reversed configuration (FRC) confinement chamber. Positioning the probe at multiple axial positions and taking multiple repeatable shots allows for a full r-z map of the magnetic field. Measurements were made for odd-parity rotating magnetic field (RMF) antennas and even-parity RMF. The steady state data from applying a 10 kHz low pass filter used in conjunction with data at the RMF frequency yields a map of the full 3D rotating field structure. Comparisons will be made to the 3D magnetic structure predicted by NIMROD simulations, with parameters adjusted to match that of the TCSU experiments. The probe provides sufficient data to utilize a Maxwell stress tensor approach to directly measure the torque applied to the FRC's electrons, which combined with a resistive torque model, yields an estimate of the average FRC resistivity.

  1. Improved confinement and current drive of high temperature field reversed configurations in the new translation, confinement, and sustainment upgrade device

    SciTech Connect (OSTI)

    Guo, H. Y.; Hoffman, A. L.; Milroy, R. D.; Steinhauer, L. C.; Brooks, R. D.; Deards, C. L.; Grossnickle, J. A.; Melnik, P.; Miller, K. E.; Vlases, G. C.

    2008-05-15

    Previous work in the translation, confinement, and sustainment (TCS) device [Hoffman, Guo, Slough et al., Fusion Sci. Technol. 41, 92 (2002)] demonstrated formation and steady-state sustainment of field reversed configurations (FRC) by rotating magnetic fields (RMF). However, in TCS the plasma temperature was limited to several 10 s of eV due to high impurity content. These impurities are greatly reduced in the new TCS upgrade device (TCSU), which was built with a bakable, ultrahigh vacuum chamber, and advanced wall conditioning capabilities. This led to dramatic improvements in TCSU with temperatures well over 200 eV, using simple even-parity RMF drive. The higher temperatures, coupled with reduced recycling, allowed plasma to enter into a collisionless, high-{zeta} (ratio of average electron rotation frequency to RMF frequency) regime. These new FRC states exhibit the following key features: (1) Dramatic improvement in current drive efficiency with {zeta} approaching 100%, for the first time in TCSU; (2) up to threefold increase in global energy confinement time; and (3) significant reduction in transport rates, accompanied by a striking transition from a Bohm-type transport to a lower hybrid driftlike transport that scales better than gyro-Bohm and is very favorable for the next step FRC development.

  2. Effects of internal structure on equilibrium of field-reversed configuration plasma sustained by rotating magnetic field

    SciTech Connect (OSTI)

    Yambe, Kiyoyuki; Inomoto, Michiaki; Okada, Shigefumi; Kobayashi, Yuka; Asai, Tomohiko

    2008-09-15

    The effects of an internal structure on the equilibrium of a field-reversed configuration (FRC) plasma sustained by rotating magnetic field is investigated by using detailed electrostatic probe measurements in the FRC Injection Experiment apparatus [S. Okada, et al., Nucl. Fusion. 45, 1094 (2005)]. An internal structure installed axially on the geometrical axis, which simulates Ohmic transformer or external toroidal field coils on the FRC device, brings about substantial changes in plasma density profile. The internal structure generates steep density-gradients not only on the inner side but on the outer side of the torus. The radial electric field is observed to sustain the ion thermal pressure-gradient in the FRC without the internal structure; however, the radial electric field is not sufficient to sustain the increased ion thermal pressure-gradient in the FRC with the internal structure. Spontaneously driven azimuthal ion flow will be accountable for the imbalance of the radial pressure which is modified by the internal structure.

  3. Twenty-channel bolometer array for studying impurity radiation and transport in the TCS field-reversed configuration

    SciTech Connect (OSTI)

    Kostora, M. R.; Hsu, S. C.; Wurden, G. A.

    2006-10-15

    A bolometer array diagnostic has been developed for the University of Washington Translation, Confinement, and Sustainment (TCS) field-reversed configuration (FRC) experiment in order to measure radially resolved total radiated power per unit length of the FRC. This will provide radiation energy loss information, useful in power balance and impurity studies. The 20-element photodiode bolometer will be mounted at the midplane of the TCS cylindrical vacuum chamber to view the rotating magnetic field (RMF) generated FRC plasma. Key features of this new bolometer array are (1) extensive electrical shielding against the RMF, (2) robust electrical isolation, (3) trans-impedance amplifiers using a microcoax interface at the array and a fiber optic interface to the screen room, and (4) a custom glass-on-metal socket for the 20-element photodiode chip to ensure high vacuum compatibility. The bolometer array can be retracted behind a gate valve using a stepper motor to protect it during vacuum chamber bakeout. The slit assembly housing is interchangeable to provide flexibility for the viewing sightlines.

  4. Numerical Study of the Formation, Ion Spin-up and Nonlinear Stability Properties of Field-reversed Configurations

    SciTech Connect (OSTI)

    E.V. Belova; R.C. Davidson; H. Ji; M. Yamada; C.D. Cothran; M.R. Brown; M.J. Schaffer

    2004-11-12

    Results of three-dimensional numerical simulations of field-reversed configurations (FRCs) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs and the new FRC formation method by the counter-helicity spheromak merging. Kinetic simulations show nonlinear saturation of the n = 1 tilt mode, where n is the toroidal mode number. The n = 2 and n = 3 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to the ion spin-up in the toroidal direction. The ion toroidal spin-up is shown to be related to the resistive decay of the internal flux, and the resulting loss of particle confinement. Three-dimensional MHD simulations of counter-helicity spheromak merging and FRC formation show good agreement with results from the SSX-FRC experiment. Simulations show formation of an FRC in about 30 Alfven times for typical experimental parameters. The growth rate of the n = 1 tilt mode is shown to be significantly reduced compared to the MHD growth rate due to the large plasma viscosity and field-line-tying effects.

  5. Upregulation of Cannabinoid Type 1 Receptors in Dopamine D2 Receptor Knockout Mice Is Reversed by Chronic Forced Ethanol Consumption

    SciTech Connect (OSTI)

    Thanos, P.K.; Wang, G.; Thanos, P.K.; Gopez, V.; Delis, F.; Michaelides, M.; Grand, D.K.; Wang, G.-J.; Kunos, G.; Volkow, N.D.

    2011-01-01

    The anatomical proximity of the cannabinoid type 1 (CNR1/CB1R) and the dopamine D2 receptors (DRD2), their ability to form CB1R-DRD2 heteromers, their opposing roles in locomotion, and their involvement in ethanol's reinforcing and addictive properties prompted us to study the levels and distribution of CB1R after chronic ethanol intake, in the presence and absence of DRD2. We monitored the drinking patterns and locomotor activity of Drd2+/+ and Drd2-/- mice consuming either water or a 20% (v/v) ethanol solution (forced ethanol intake) for 6 months and used the selective CB1 receptor antagonist [{sup 3}H]SR141716A to quantify CB1R levels in different brain regions with in vitro receptor autoradiography. We found that the lack of DRD2 leads to a marked upregulation (approximately 2-fold increase) of CB1R in the cerebral cortex, the caudate-putamen, and the nucleus accumbens, which was reversed by chronic ethanol intake. The results suggest that DRD2-mediated dopaminergic neurotransmission and chronic ethanol intake exert an inhibitory effect on cannabinoid receptor expression in cortical and striatal regions implicated in the reinforcing and addictive properties of ethanol.

  6. Analysis of first order reversal curves in the thermal hysteresis of spin-crossover nanoparticles within the mechanoelastic model

    SciTech Connect (OSTI)

    Stoleriu, Laurentiu E-mail: cristian.enachescu@uaic.ro; Stancu, Alexandru; Enachescu, Cristian E-mail: cristian.enachescu@uaic.ro; Chakraborty, Pradip; Hauser, Andreas

    2015-05-07

    The recently obtained spin-crossover nanoparticles are possible candidates for applications in the recording media industry as materials for data storage, or as pressure and temperature sensors. For these applications, the intermolecular interactions and interactions between spin-crossover nanoparticles are extremely important, as they may be essential factors in triggering the transition between the two stable phases: the high-spin and low-spin ones. In order to find correlations between the distributions in size and interactions and the transition temperatures distribution, we apply the FORC (First Order Reversal Curves) method, using simulations based on a mechanoelastic model applied to 2D triangular lattices composed of molecules linked by springs and embedded in a surfactant. We consider two Gaussian distributions: one is the size of the nanoparticles and another is the elastic interactions between edge spin-crossover molecules and the surfactant molecules. In order to disentangle the kinetic and non-kinetic parts of the FORC distributions, we compare the results obtained for different temperature sweeping rates. We also show that the presence of few larger particles in a distribution centered around much smaller particles dramatically increases the hysteresis width.

  7. Crystal structures of the reverse transcriptase-associated ribonuclease H domain of xenotropic murine leukemia-virus related virus

    SciTech Connect (OSTI)

    Zhou, Dongwen; Chung, Suhman; Miller, Maria; Le Grice, Stuart F.J.; Wlodawer, Alexander

    2012-06-19

    The ribonuclease H (RNase H) domain of retroviral reverse transcriptase (RT) plays a critical role in the life cycle by degrading the RNA strands of DNA/RNA hybrids. In addition, RNase H activity is required to precisely remove the RNA primers from nascent (-) and (+) strand DNA. We report here three crystal structures of the RNase H domain of xenotropic murine leukemia virus-related virus (XMRV) RT, namely (i) the previously identified construct from which helix C was deleted, (ii) the intact domain, and (iii) the intact domain complexed with an active site {alpha}-hydroxytropolone inhibitor. Enzymatic assays showed that the intact RNase H domain retained catalytic activity, whereas the variant lacking helix C was only marginally active, corroborating the importance of this helix for enzymatic activity. Modeling of the enzyme-substrate complex elucidated the essential role of helix C in binding a DNA/RNA hybrid and its likely mode of recognition. The crystal structure of the RNase H domain complexed with {beta}-thujaplicinol clearly showed that coordination by two divalent cations mediates recognition of the inhibitor.

  8. Reversible micromachining locator

    DOE Patents [OSTI]

    Salzer, Leander J. (Los Almos, NM); Foreman, Larry R. (late of Los Alamos, NM)

    2002-01-01

    A locator with a part support is used to hold a part onto the kinematic mount of a tooling machine so that the part can be held in or replaced in exactly the same position relative to the cutting tool for machining different surfaces of the part or for performing different machining operations on the same or different surfaces of the part. The locator has disposed therein a plurality of steel balls placed at equidistant positions around the planar surface of the locator and the kinematic mount has a plurality of magnets which alternate with grooves which accommodate the portions of the steel balls projecting from the locator. The part support holds the part to be machined securely in place in the locator. The locator can be easily detached from the kinematic mount, turned over, and replaced onto the same kinematic mount or another kinematic mount on another tooling machine without removing the part to be machined from the locator so that there is no need to touch or reposition the part within the locator, thereby assuring exact replication of the position of the part in relation to the cutting tool on the tooling machine for each machining operation on the part.

  9. OHA Case Reversed

    Broader source: Energy.gov [DOE]

    A final determination was made by the Department of Energy Headquarters Appeal Panel to restore the individual's DOE access authorization.

  10. Reversible hydrogen storage materials

    DOE Patents [OSTI]

    Ritter, James A. (Lexington, SC); Wang, Tao (Columbia, SC); Ebner, Armin D. (Lexington, SC); Holland, Charles E. (Cayce, SC)

    2012-04-10

    In accordance with the present disclosure, a process for synthesis of a complex hydride material for hydrogen storage is provided. The process includes mixing a borohydride with at least one additive agent and at least one catalyst and heating the mixture at a temperature of less than about 600.degree. C. and a pressure of H.sub.2 gas to form a complex hydride material. The complex hydride material comprises MAl.sub.xB.sub.yH.sub.z, wherein M is an alkali metal or group IIA metal, Al is the element aluminum, x is any number from 0 to 1, B is the element boron, y is a number from 0 to 13, and z is a number from 4 to 57 with the additive agent and catalyst still being present. The complex hydride material is capable of cyclic dehydrogenation and rehydrogenation and has a hydrogen capacity of at least about 4 weight percent.

  11. Final Report on Development of Optimized Field-Reversed Configuration Plasma Formation Techniques for Magnetized Target Fusion

    SciTech Connect (OSTI)

    Lynn, Alan

    2013-11-01

    The University of New Mexico (UNM) proposed a collaboration with Los Alamos National Laboratory (LANL) to develop and test methods for improved formation of field-reversed configuration (FRC) plasmas relevant to magnetized target fusion (MTF) energy research. MTF is an innovative approach for a relatively fast and cheap path to the production of fusion energy that utilizes magnetic confinement to assist in the compression of a hot plasma to thermonuclear conditions by an external driver. LANL is currently pursing demonstration of the MTF concept via compression of an FRC plasma by a metal liner z-pinch in conjunction with the Air Force Research Laboratory in Albuquerque, NM. A key physics issue for the FRC's ultimate success as an MTF target lies in the initial pre-ionization (PI) stage. The PI plasma sets the initial conditions from which the FRC is created. In particular, the PI formation process determines the amount of magnetic flux that can be trapped to form the FRC. A ringing theta pinch ionization (RTPI) technique, such as currently used by the FRX-L device at LANL, has the advantages of high ionization fraction, simplicity (since no additional coils are required), and does not require internal electrodes which can introduce impurities into the plasma. However RTPI has been shown to only trap #24;50% of the initial bias flux at best and imposes additional engineering constraints on the capacitor banks. The amount of trapped flux plays an important role in the FRC's final equilibrium, transport, and stability properties, and provides increased ohmic heating of the FRC through induced currents as the magnetic field decays. Increasing the trapped flux also provides the route to greatest potential gains in FRC lifetime, which is essential to provide enough time to translate and compress the FRC effectively. In conjunction with LANL we initially planned to develop and test a microwave break- down system to improve the initial PI plasma formation. The UNM team would design the microwave optics and oversee the fabrication and assembly of all components and assist with integration into the FRX-L machine control system. LANL would provide a preexisting 65 kW X-band microwave source and some associated waveguide hardware. Once constructed and installed, UNM would take the lead in operating the microwave breakdown system and conducting studies to optimize its use in FRC PI formation in close cooperation with the needs of the LANL MTF team. In conjunction with our LANL collaborators, we decided after starting the project to switch from a microwave plasma breakdown approach to a plasma gun technology to use for enhanced plasma formation in the FRX-L field-reversed configuration experiment at LANL. Plasma guns would be able to provide significantly higher density plasma with greater control over its distribution in time and space within the experiment. This would allow greater control and #12;ne-tuning of the PI plasma formed in the experiment. Multiple plasma guns would be employed to fill a Pyrex glass test chamber (built at UNM) with plasma which would then be characterized and optimized for the MTF effort.

  12. Analysis of magnetic probe signals including effect of cylindrical conducting wall for field-reversed configuration experiment

    SciTech Connect (OSTI)

    Ikeyama, Taeko; Hiroi, Masanori; Nemoto, Yuuichi; Nogi, Yasuyuki

    2008-06-15

    A confinement field is disturbed by magnetohydrodynamic (MHD) motions of a field-reversed configuration (FRC) plasma in a cylindrical conductor. The effect of the conductor should be included to obtain a spatial structure of the disturbed field with a good precision. For this purpose, a toroidal current in the plasma and an eddy current on a conducting wall are replaced by magnetic dipole and image magnetic dipole moments, respectively. Typical spatial structures of the disturbed field are calculated by using the dipole moments for such MHD motions as radial shift, internal tilt, external tilt, and n=2 mode deformation. Then, analytic formulas for estimating the shift distance, tilt angle, and deformation rate of the MHD motions from magnetic probe signals are derived. It is estimated from the calculations by using the dipole moments that the analytic formulas include an approximately 40% error. Two kinds of experiment are carried out to investigate the reliability of the calculations. First, a magnetic field produced by a circular current is measured in an aluminum pipe to confirm the replacement of the eddy current with the image magnetic dipole moments. The measured fields coincide well with the calculated values including the image magnetic dipole moments. Second, magnetic probe signals measured from the FRC plasma are substituted into the analytic formulas to obtain shift distance and deformation rate. The experimental results are compared to the MHD motions measured by using a radiation from the plasma. If the error included in the analytic formulas and the difference between the magnetic and optical structures in the plasma are considered, the results of the radiation measurement support well those of the magnetic analysis.

  13. On-Site Pilot Study - Removal of Uranium, Radium-226 and Arsenic from Impacted Leachate by Reverse Osmosis - 13155

    SciTech Connect (OSTI)

    McMurray, Allan; Everest, Chris; Rilling, Ken; Vandergaast, Gary; LaMonica, David

    2013-07-01

    Conestoga-Rovers and Associates (CRA-LTD) performed an on-site pilot study at the Welcome Waste Management Facility in Port Hope, Ontario, Canada, to evaluate the effectiveness of a unique leachate treatment process for the removal of radioactive contaminants from leachate impacted by low-level radioactive waste. Results from the study also provided the parameters needed for the design of the CRA-LTD full scale leachate treatment process design. The final effluent water quality discharged from the process to meet the local surface water discharge criteria. A statistical software package was utilized to obtain the analysis of variance (ANOVA) for the results from design of experiment applied to determine the effect of the evaluated factors on the measured responses. The factors considered in the study were: percent of reverse osmosis permeate water recovery, influent coagulant dosage, and influent total dissolved solids (TDS) dosage. The measured responses evaluated were: operating time, average specific flux, and rejection of radioactive contaminants along with other elements. The ANOVA for the design of experiment results revealed that the operating time is affected by the percent water recovery to be achieved and the flocculant dosage over the range studied. The average specific flux and rejection for the radioactive contaminants were not affected by the factors evaluated over the range studied. The 3 month long on-site pilot testing on the impacted leachate revealed that the CRA-LTD leachate treatment process was robust and produced an effluent water quality that met the surface water discharge criteria mandated by the Canadian Nuclear Safety Commission and the local municipality. (authors)

  14. Magnetoresistance reversal in antiperovskite compound Mn{sub 3}Cu{sub 0.5}Zn{sub 0.5}N

    SciTech Connect (OSTI)

    Zhang, X. H.; Yin, Y.; Yuan, Q.; Han, J. C. [Center for Composite Materials, Harbin Institute of Technology, Harbin 150080 (China); Zhang, Z. H. [Liaoning Key Materials Laboratory for Railway, School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028 (China); Jian, J. K. [School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006 (China); Zhao, J. G., E-mail: zhaojinggeng@163.com, E-mail: songbo@hit.edu.cn; Song, B., E-mail: zhaojinggeng@163.com, E-mail: songbo@hit.edu.cn [Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080 (China)

    2014-03-28

    We report detailed investigations of the structure, magnetic properties, electronic transport, and specific heat in Mn-based antiperovskite compounds Mn{sub 3}Cu{sub 0.5}Zn{sub 0.5}N. Most strikingly, there are several fascinating features: (i) The magnetoresistance at 30?kOe (40?kOe) exceeds ?1% (?2%) over a temperature span of ?70?K (?25?K) from 5 to 140?K; (ii) magnetoresistance fluctuates at temperatures of 100200?K, including an obvious sign reversal from negative to positive at ?140?K. Analysis of the specific heat reveals that the magnetoresistance reversal may originate from the reconstruction of the Fermi surface accompanying an antiferromagnetic-ferromagnetic transition.

  15. Physics-Based Compact Model for CIGS and CdTe Solar Cells: From Voltage-Dependent Carrier Collection to Light-Enhanced Reverse Breakdown: Preprint

    SciTech Connect (OSTI)

    Sun, Xingshu; Alam, Muhammad Ashraful; Raguse, John; Garris, Rebekah; Deline, Chris; Silverman, Timothy

    2015-10-15

    In this paper, we develop a physics-based compact model for copper indium gallium diselenide (CIGS) and cadmium telluride (CdTe) heterojunction solar cells that attributes the failure of superposition to voltage-dependent carrier collection in the absorber layer, and interprets light-enhanced reverse breakdown as a consequence of tunneling-assisted Poole-Frenkel conduction. The temperature dependence of the model is validated against both simulation and experimental data for the entire range of bias conditions. The model can be used to characterize device parameters, optimize new designs, and most importantly, predict performance and reliability of solar panels including the effects of self-heating and reverse breakdown due to partial-shading degradation.

  16. Warm white light emitting ThO{sub 2}:Sm{sup 3+} nanorods: Cationic surfactant assisted reverse micellar synthesis and Photoluminescence properties

    SciTech Connect (OSTI)

    Gupta, Santosh K.; Gupta, Ruma; Natarajan, V.; Godbole, S.V.

    2014-01-01

    Graphical abstract: - Highlights: ThO{sub 2}:Sm{sup 3+} nanoparticles have been synthesized using cationic surfactant assisted reverse micellar route. HRTEM shows the formation of thoria nanorods. Photoluminescence investigation shows host as well as samarium ion emission. Time resolved fluorescence spectroscopy shows the presence of two types of samarium ion in thoria host. - Abstract: Sm{sup 3+} activated thorium oxide nanorods were synthesized by cationic surfactant assisted reverse micellar route. Phase purity, morphological and luminescent properties were investigated by X-ray diffraction, high resolution transmission electron microscopy and photoluminescence spectroscopy. Upon UV light excitation (245 nm), ThO{sub 2}:Sm{sup 3+} exhibited host emission at 447 nm, along with characteristic emission lines of Sm{sup 3+} at 569, 609, 662 and 716 nm. Lifetime spectroscopy shows the presence of two types of Sm{sup 3+} (? = 1.1 ms and 4.9 ms) with different asymmetric ratios.

  17. Dynamic Formation of a Hot Field Reversed Configuration with Improved Confinement by Supersonic Merging of Two Colliding High-{beta} Compact Toroids

    SciTech Connect (OSTI)

    Binderbauer, M. W.; Guo, H. Y.; Tuszewski, M.; Putvinski, S.; Sevier, L.; Barnes, D.; Rostoker, N.; Anderson, M. G.; Andow, R.; Bonelli, L.; Brown, R.; Bui, D. Q.; Bystritskii, V.; Clary, R.; Cheung, A. H.; Conroy, K. D.; Deng, B. H.; Dettrick, S. A.; Douglass, J. D.; Feng, P.

    2010-07-23

    A hot stable field-reversed configuration (FRC) has been produced in the C-2 experiment by colliding and merging two high-{beta} plasmoids preformed by the dynamic version of field-reversed {theta}-pinch technology. The merging process exhibits the highest poloidal flux amplification obtained in a magnetic confinement system (over tenfold increase). Most of the kinetic energy is converted into thermal energy with total temperature (T{sub i}+T{sub e}) exceeding 0.5 keV. The final FRC state exhibits a record FRC lifetime with flux confinement approaching classical values. These findings should have significant implications for fusion research and the physics of magnetic reconnection.

  18. Magnetic field, frequency and temperature dependence of complex conductance of ultrathin La1.65Sr0.45CuO4/La2CuO4 films and the organic superconductors κ-(BEDT-TTF)2Cu[N(CN)2]Br

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

    V. A. Gasparov; Bozovic, I.; He, Xi; Dubuis, G.; Pavuna, D.; Kushch, N. D.; Yagubskii, E. B.; Schlueter, J. A.

    2015-09-01

    In this study, we used atomic-layer molecular beam epitaxy (ALL-MBE) to synthesize bilayer films of a cuprate metal (La1.65Sr0.45CuO4) and a cuprate insulator (La2CuO4), in which interface superconductivity occurs in a layer that is just one-half unit cell thick. We have studied the magnetic field and temperature dependence of the complex sheet conductance, σ(ω), of these films, and compared them to κκ-(BEDT-TTF)2Cu[N(CN)2]Br single crystals. The magnetic field H was applied both parallel and perpendicular to the 2D conducting layers. Experiments have been carried out at frequencies between 23 kHz and 50 MHz using either two-coil mutual inductance technique, or themore » LC resonators with spiral or rectangular coils. The real and the imaginary parts of the mutual-inductance M(T,ω) between the coil and the sample were measured and converted to complex conductivity. For H perpendicular to the conducting layers, we observed almost identical behavior in both films and κ-Br single crystals: (i) the transition onset in the inductive response, Lk–1(T) occurs at a temperature lower by 2 K than in Re σ(T), (ii) this shift is almost constant with magnetic field up to 8 T; (iii) the vortex diffusion constant D(T) is exponential due to pinning of vortex cores. These results can be described by the extended dynamic theory of the Berezinski–Kosterlitz–Thouless (BKT) transition and dynamics of bound vortex–antivortex pairs with short separation lengths.« less

  19. Defect Band Luminescence Intensity Reversal as Related to Application of Anti-Reflection Coating on mc-Si PV Cells: Preprint

    SciTech Connect (OSTI)

    Guthrey, H.; Johnston, S.; Yan, F.; Gorman, B.; Al-Jassim, M.

    2012-06-01

    Photoluminescence (PL) imaging is widely used to identify defective regions within mc-Si PV cells. Recent PL imaging investigations of defect band luminescence (DBL) in mc-Si have revealed a perplexing phenomenon. Namely, the reversal of the DBL intensity in various regions of mc-Si PV material upon the application of a SiNx:H anti-reflective coating (ARC). Regions with low DBL intensity before ARC application often exhibit high DBL intensity afterwards, and the converse is also true. PL imaging alone cannot explain this effect. We have used high resolution cathodoluminescence (CL) spectroscopy and electron beam induced current (EBIC) techniques to elucidate the origin of the DBL intensity reversal. Multiple sub-bandgap energy levels were identified that change in peak position and intensity upon the application of the ARC. Using this data, in addition to EBIC contrast information, we provide an explanation for the DBL intensity reversal based on the interaction of the detected energy levels with the SiNx:H ARC application. Multiple investigations have suggested that this is a global problem for mc-Si PV cells. Our results have the potential to provide mc-Si PV producers a pathway to increased efficiencies through defect mitigation strategies.

  20. Structure of AgI-doped Ge-In-S glasses: Experiment, reverse Monte Carlo modelling, and density functional calculations

    SciTech Connect (OSTI)

    Chrissanthopoulos, A.; Jovari, P.; Kaban, I.; Gruner, S.; Kavetskyy, T.; Borc, J.; Wang, W.; Ren, J.; Chen, G.; Yannopoulos, S.N.

    2012-08-15

    We report an investigation of the structure and vibrational modes of Ge-In-S-AgI bulk glasses using X-ray diffraction, EXAFS spectroscopy, Reverse Monte-Carlo (RMC) modelling, Raman spectroscopy, and density functional theoretical (DFT) calculations. The combination of these techniques made it possible to elucidate the short- and medium-range structural order of these glasses. Data interpretation revealed that the AgI-free glass structure is composed of a network where GeS{sub 4/2} tetrahedra are linked with trigonal InS{sub 3/2} units; S{sub 3/2}Ge-GeS{sub 3/2} ethane-like species linked with InS{sub 4/2}{sup -} tetrahedra form sub-structures which are dispersed in the network structure. The addition of AgI into the Ge-In-S glassy matrix causes appreciable structural changes, enriching the Indium species with Iodine terminal atoms. The existence of trigonal species InS{sub 2/2}I and tetrahedral units InS{sub 3/2}I{sup -} and InS{sub 2/2}I{sub 2}{sup -} is compatible with the EXAFS and RMC analysis. Their vibrational properties (harmonic frequencies and Raman activities) calculated by DFT are in very good agreement with the experimental values determined by Raman spectroscopy. - Graphical abstract: Experiment (XRD, EXAFS, RMC, Raman scattering) and density functional calculations are employed to study the structure of AgI-doped Ge-In-S glasses. The role of mixed structural units as illustrated in the figure is elucidated. Highlights: Black-Right-Pointing-Pointer Doping Ge-In-S glasses with AgI causes significant changes in glass structure. Black-Right-Pointing-Pointer Experiment and DFT are combined to elucidate short- and medium-range structural order. Black-Right-Pointing-Pointer Indium atoms form both (InS{sub 4/2}){sup -} tetrahedra and InS{sub 3/2} planar triangles. Black-Right-Pointing-Pointer (InS{sub 4/2}){sup -} tetrahedra bond to (S{sub 3/2}Ge-GeS{sub 3/2}){sup 2+} ethane-like units forming neutral sub-structures. Black-Right-Pointing-Pointer Mixed chalcohalide species (InS{sub 3/2}I){sup -} offer vulnerable sites for the uptake of Ag{sup +}.

  1. Simulation study of wave phenomena from the sheath region in single frequency capacitively coupled plasma discharges; field reversals and ion reflection

    SciTech Connect (OSTI)

    Sharma, S.; Turner, M. M.

    2013-07-15

    Capacitively coupled radio-frequency (RF) discharges have great significance for industrial applications. Collisionless electron heating in such discharges is important, and sometimes is the dominant mechanism. This heating is usually understood to originate in a stochastic interaction between electrons and the electric fields. However, other mechanisms may also be important. There is evidence of wave emission with a frequency near the electron plasma frequency, i.e., ?{sub pe}, from the sheath region in collisionless capacitive RF discharges. This is the result of a progressive breakdown of quasi-neutrality close to the electron sheath edge. These waves are damped in a few centimeters during their propagation from the sheath towards the bulk plasma. The damping occurs because of the Landau damping or some related mechanism. This research work reports that the emission of waves is associated with a field reversal during the expanding phase of the sheath. Trapping of electrons near to this field reversal region is observed. The amplitude of the wave increases with increasing RF current density amplitude J(tilde sign){sub 0} until some maximum is reached, beyond which the wave diminishes and a new regime appears. In this new regime, the density of the bulk plasma suddenly increases because of ion reflection, which occurs due to the presence of strong field reversal near sheath region. Our calculation shows that these waves are electron plasma waves. These phenomena occur under extreme conditions (i.e., higher J(tilde sign){sub 0} than in typical experiments) for sinusoidal current waveforms, but similar effects may occur with non-sinusoidal pulsed waveforms for conditions of experimental interest, because the rate of change of current is a relevant parameter. The effect of electron elastic collisions on plasma waves is also investigated.

  2. Waste treatment by reverse osmosis and membrane processes: Industrial. (Latest citations from the EI Compendex*plus database). NewSearch

    SciTech Connect (OSTI)

    Not Available

    1994-10-01

    The bibliography contains citations concerning the use of membranes in the treatment of industrial wastewaters. Reverse osmosis, ion exchange, electrodialysis, liquid membranes, and ultrafiltration techniques are described. Wastewater treatments for removal of metals, ammonia, sodium compounds, nitrates, fluorides, dyes, biologicals, and radioactive waste using membrane technology are discussed. Applications of this technology to the chemical, petrochemical, pulp, textile, steel, ore treatment, electro-plating, and other wastewater and groundwater-remediation industries are included. (Contains 250 citations and includes a subject term index and title list.)

  3. Amino acid modified Ni catalyst exhibits reversible H2 oxidation/production over a broad pH range at elevated temperatures

    SciTech Connect (OSTI)

    Dutta, Arnab; DuBois, Daniel L.; Roberts, John A.; Shaw, Wendy J.

    2014-11-18

    Hydrogenases interconvert H2 and protons at high rates and with high energy efficiencies, providing inspiration for the development of molecular catalysts. Studies designed to determine how the protein scaffold can influence a catalytically active site has led to the synthesis of amino acid derivatives, [Ni(PCy2NAmino acid2)2]2+ (CyAA), of [Ni(PR2NR'2)2]2+ complexes. It is shown that these CyAA derivatives can catalyze fully reversible H2 production/oxidation, a feature reminiscent of enzymes. The reversibility is achieved in acidic aqueous solutions, 0.25% H2/Ar, and elevated temperatures (tested up to 348 K) for the glycine (CyGly), arginine (CyArg), and arginine methyl ester (CyArgOMe) derivatives. As expected for a reversible process, the activity is dependent upon H2 and proton concentration. CyArg is significantly faster in both directions than the other two derivatives (~300 s-1 H2 production and 20 s-1 H2 oxidation; pH=1, 348 K). The significantly slower rates for CyArgOMe (35 s-1 production and 7 s-1 oxidation) compared to CyArg suggests an important role for the COOH group during catalysis. That CyArg is faster than CyGly (3 s-1 production and 4 s-1 oxidation under the same conditions) suggests that the additional structural features imparted by the guanidinium groups facilitate fast and reversible H2 addition/release. These observations demonstrate that appended, outer coordination sphere amino acids work in synergy with the active site and can play an equally important role for synthetic molecular electrocatalysts as the protein scaffold does for redox active enzymes. This work was funded by the Office of Science Early Career Research Program through the US DOE, BES (AD, WJS), and the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the US DOE, BES (DLD, JASR). PNNL is operated by Battelle for the US DOE.

  4. Characterizing toxic emissions from a coal-fired power plant demonstrating the AFGD ICCT Project and a plant utilizing a dry scrubber/baghouse system: Bailly Station Units 7 and 8 and AFGD ICCT Project. Final report. Final report

    SciTech Connect (OSTI)

    Dismukes, E.B.

    1994-10-20

    This report describes results of assessment of the risk of emissions of hazardous air pollutants at one of the electric power stations, Bailly Station, which is also the site of a Clean Coal Technology project demonstrating the Pure Air Advanced Flue Gas Desulfurization process (wet limestone). This station represents the configuration of no NO{sub x} reduction, particulate control with electrostatic precipitators, and SO{sub 2} control with a wet scrubber. The test was conducted September 3--6, 1993. Sixteen trace metals were determined along with 5 major metals. Other inorganic substances and organic compounds were also determined.

  5. On the relationships between the Michaelis–Menten kinetics, reverse Michaelis–Menten kinetics, equilibrium chemistry approximation kinetics, and quadratic kinetics

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

    Tang, J. Y.

    2015-12-01

    The Michaelis–Menten kinetics and the reverse Michaelis–Menten kinetics are two popular mathematical formulations used in many land biogeochemical models to describe how microbes and plants would respond to changes in substrate abundance. However, the criteria of when to use either of the two are often ambiguous. Here I show that these two kinetics are special approximations to the equilibrium chemistry approximation (ECA) kinetics, which is the first-order approximation to the quadratic kinetics that solves the equation of an enzyme–substrate complex exactly for a single-enzyme and single-substrate biogeochemical reaction with the law of mass action and the assumption of a quasi-steadymore » state for the enzyme–substrate complex and that the product genesis from enzyme–substrate complex is much slower than the equilibration between enzyme–substrate complexes, substrates, and enzymes. In particular, I show that the derivation of the Michaelis–Menten kinetics does not consider the mass balance constraint of the substrate, and the reverse Michaelis–Menten kinetics does not consider the mass balance constraint of the enzyme, whereas both of these constraints are taken into account in deriving the equilibrium chemistry approximation kinetics. By benchmarking against predictions from the quadratic kinetics for a wide range of substrate and enzyme concentrations, the Michaelis–Menten kinetics was found to persistently underpredict the normalized sensitivity ∂ ln v / ∂ ln k2+ of the reaction velocity v with respect to the maximum product genesis rate k2+, persistently overpredict the normalized sensitivity ∂ ln v / ∂ ln k1+ of v with respect to the intrinsic substrate affinity k1+, persistently overpredict the normalized sensitivity ∂ ln v / ∂ ln [E]T of v with respect the total enzyme concentration [E]T, and persistently underpredict the normalized sensitivity ∂ ln v / ∂ ln [S]T of v with respect to the total substrate concentration [S]T. Meanwhile, the reverse Michaelis–Menten kinetics persistently underpredicts ∂ ln v / ∂ ln k2+ and ∂ ln v / ∂ ln [E]T, and persistently overpredicts ∂ ln v / ∂ ln k1+ and ∂ ln v / ∂ ln [S]T. In contrast, the equilibrium chemistry approximation kinetics always gives consistent predictions of ∂ ln v / ∂ ln k2+, ∂ ln v / ∂ ln k1+, ∂ ln v / ∂ ln [E]T, and ∂ ln v / ∂ ln [S]T, indicating that ECA-based models will be more calibratable if the modeled processes do obey the law of mass action. Since the equilibrium chemistry approximation kinetics includes advantages from both the Michaelis–Menten kinetics and the reverse Michaelis–Menten kinetics and it is applicable for almost the whole range of substrate and enzyme abundances, land biogeochemical modelers therefore no longer need to choose when to use the Michaelis–Menten kinetics or the reverse Michaelis–Menten kinetics. I expect that removing this choice ambiguity will make it easier to formulate more robust and consistent land biogeochemical models.« less

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

    SciTech Connect (OSTI)

    Abdel-Baset, A. M.; Rashad, M.; Moharram, A. H.

    2013-12-16

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

  7. Observations of Improved Stability and Confinement in a High-{beta} Self-Organized Spherical-Torus-Like Field-Reversed Configuration

    SciTech Connect (OSTI)

    Guo, H.Y.; Hoffman, A.L.; Steinhauer, L.C.; Miller, K.E.

    2005-10-21

    An extremely high-{beta} (over 85%) self-organized field-reversed configuration (FRC) with a spherical-torus- (ST-)like core is produced in the translation, confinement, and sustainment experiment by highly super-Alfvenic translation of a spheromaklike plasmoid. Substantial flux conversion from toroidal into poloidal occurs during the capture process, resulting in the ST-like core. This plasma state exhibits a remarkable stabilizing property for the ubiquitous n=2 centrifugally driven interchange modes present in {theta}-pinch formed FRCs. This is explained, for the first time, by a simple model taking into account magnetic shear and centrifugal effects. The FRC-ST configuration has up to 4 times improvement in flux confinement times over the scaling of conventional {theta}-pinch formed FRCs and, thus, a significant improvement in the resistivity and transport.

  8. In situ resonant Raman scattering and reversible photoinduced structural change in YBa{sub 2}Cu{sub 3}O{sub 6+x}

    SciTech Connect (OSTI)

    Osada, Minoru; Kaell, Mikael; Baeckstroem, Joakim; Kakihana, Masato; Andersen, Niels Hessel; Boerjesson, Lars

    2005-06-01

    We report on bidirectional photoswitching associated with the CuO chains in oxygen-deficient YBa{sub 2}Cu{sub 3}O{sub 6+x} single crystals. By varying the wavelength of light polarized along the CuO chains, the material can be reversibly switched between two metastable states characterized by the existence or absence of a specific Raman scattering resonance. A comparison of the spectral efficiencies for this photoswitching with analogous data for the persistent photoconductivity and photoconductivity quenching effects suggests that the two phenomena have the same microscopic origin. We argue that the effects are due to photoinduced Cu-O charge-transfer excitations, which destabilize chains of different length depending on wavelength, and promote the growth of thermally inaccessible oxygen ordering configurations.

  9. Investigating the reversibility of structural modifications of LixNiyMnzCo1-y-zO₂ cathode materials during initial charge/discharge, at multiple length scales

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

    Hwang, Sooyeon; Bak, Seong -Min; Kim, Seung Min; Chung, Kyung Yoon; Chang, Wonyoung

    2015-08-11

    In this work, we investigate the structural modifications occurring at the bulk, subsurface, and surface scales of LixNiyMnzCo1-y-zO₂ (NMC; y, z = 0.8, 0.1 and 0.4, 0.3, respectively) cathode materials during the initial charge/discharge. Various analytical tools, such as X-ray diffraction, selected-area electron diffraction, electron energy-loss spectroscopy, and high-resolution electron microscopy, are used to examine the structural properties of the NMC cathode materials at the three different scales. Cut-off voltages of 4.3 and 4.8 V are applied during the electrochemical tests as the normal and extreme conditions, respectively. The high-Ni-content NMC cathode materials exhibit unusual behaviors, which is deviate frommore » the general redox reactions during the charge or discharge. The transition metal (TM) ions in the high-Ni-content NMC cathode materials, which are mostly Ni ions, are reduced at 4.8 V, even though TMs are usually oxidized to maintain charge neutrality upon the removal of Li. It was found that any changes in the crystallographic and electronic structures are mostly reversible down to the sub-surface scale, despite the unexpected reduction of Ni ions. However, after the discharge, traces of the phase transitions remain at the edges of the NMC cathode materials at the scale of a few nanometers (i.e., surface scale). This study demonstrates that the structural modifications in NMC cathode materials are induced by charge as well as discharge at multiple length scales. These changes are nearly reversible after the first cycle, except at the edges of the samples, which should be avoided because these highly localized changes can initiate battery degradation.« less

  10. RESOLVED NEAR-INFRARED SPECTROSCOPY OF WISE J104915.57-531906.1AB: A FLUX-REVERSAL BINARY AT THE L DWARF/T DWARF TRANSITION

    SciTech Connect (OSTI)

    Burgasser, Adam J.; Sheppard, Scott S.; Luhman, K. L.

    2013-08-01

    We report resolved near-infrared spectroscopy and photometry of the recently identified brown dwarf binary WISE J104915.57-531906.1AB, located 2.02 {+-} 0.15 pc from the Sun. Low-resolution spectral data from Magellan/FIRE and IRTF/SpeX reveal strong H{sub 2}O and CO absorption features in the spectra of both components, while the secondary also exhibits weak CH{sub 4} absorption at 1.6 {mu}m and 2.2 {mu}m. Spectral indices and comparison to low-resolution spectral standards indicate component types of L7.5 and T0.5 {+-} 1, the former consistent with the optical classification of the primary. Both sources also have unusually red spectral energy distributions for their spectral types, which we attribute to enhanced condensate opacity (thick clouds). Relative photometry reveals a flux reversal between the J and K bands, with the T dwarf component being brighter in the 0.95-1.3 {mu}m region ({Delta}J = -0.31 {+-} 0.05). As with other L/T transition binaries, this reversal likely reflects the depletion of condensate opacity in the T dwarf, with the contrast enhanced by the thick clouds present in the photosphere of the L dwarf primary. The 1 {mu}m flux from the T dwarf most likely emerges from gaps in its cloud layer, as suggested by the significant optical variability detected from this source by Gillon et al. Component mass measurements of the WISE J1049-5319AB system through astrometric and component radial velocity monitoring may resolve the current debate as to whether the loss of photospheric condensate clouds at the L dwarf/T dwarf boundary is a slow or rapid process, a conceivable endeavor given its proximity, brightness, small separation (3.1 {+-} 0.3 AU), and reasonable orbital period (20-30 yr)

  11. Design of a fully-fiber multi-chord interferometer and a new phase-shift demodulation method for field-reversed configuration

    SciTech Connect (OSTI)

    Fang, Dongfan Sun, Qizhi; Zhao, Xiaoming; Jia, Yuesong

    2014-05-15

    A 633 nm laser interferometer has been designed based on a novel concept, which, without the acousto-optic modulator or the demodulator circuit, adopts the fibers to connect all elements except photodetectors and oscilloscope in this system to make it more compact, portable, and efficient. The noteworthy feature is to mathematically compare the two divided interference signals, which have the same phase-shift caused by the electron density but possess the different initial phase and low angular frequencies. It is possible to read the plasma density directly on the oscilloscope by our original mathematic demodulation method without a camera. Based on the Abel inversion algorithm, the radial electron density profiles versus time can be obtained by using the multi-chord system. The designed measurable phase shift ranges from 0 to 2π rad corresponding to the maximum line integral of electron density less than 3.5 × 10{sup 17} cm{sup −2}, and the phase accuracy is about 0.017 rad corresponding to the line integral of electron density accuracy of 1 × 10{sup 15} cm{sup −2}. After the construction of eight-chord interferometer, it will provide the detailed time resolved information of the spatial distribution of the electron density in the field-reversed configuration (FRC) plasma target produced by the “Yingguang-1” programmed-discharge device, which is being constructed in the Key Laboratory of Pulsed Power, China Academy of Engineering Physics.

  12. Porous polymer monolithic columns with gold nanoparticles as an intermediate ligand for the separation of proteins in reverse phase-ion exchange mixed mode

    SciTech Connect (OSTI)

    Terborg, Lydia; Masini, Jorge C.; Lin, Michelle; Lipponen, Katriina; Riekolla, Marja -Liisa; Svec, Frantisek

    2014-11-04

    A new approach has been developed for the preparation of mixed-mode stationary phases to separate proteins. The pore surface of monolithic poly(glycidyl methacrylate-co-ethylene dimethacrylate) capillary columns was functionalized with thiols and coated with gold nanoparticles. The final mixed mode surface chemistry was formed by attaching, in a single step, alkanethiols, mercaptoalkanoic acids, and their mixtures on the free surface of attached gold nanoparticles. Use of these mixtures allowed fine tuning of the hydrophobic/hydrophilic balance. The amount of attached gold nanoparticles according to thermal gravimetric analysis was 44.8 wt.%. This value together with results of frontal elution enabled calculation of surface coverage with the alkanethiol and mercaptoalkanoic acid ligands. Interestingly, alkanethiols coverage in a range of 4.464.51 molecules/nm2 significantly exceeded that of mercaptoalkanoic acids with 2.392.45 molecules/nm2. The mixed mode character of these monolithic stationary phases was for the first time demonstrated in the separations of proteins that could be achieved in the same column using gradient elution conditions typical of reverse phase (using gradient of acetonitrile in water) and ion exchange chromatographic modes (applying gradient of salt in water), respectively.

  13. Transgenic mice that express the human multidrug-resistance gene in bone marrow enable a rapid identification of agents that reverse drug resistance

    SciTech Connect (OSTI)

    Mickisch, G.H.; Merlino, G.T.; Galski, H.; Gottesman, M.M.; Pastan, I. )

    1991-01-15

    The development of preclinical models for the rapid testing of agents that circumvent multidrug resistance in cancer is a high priority of research on drug resistance. A common form of multidrug resistance in human cancer results from expression of the MDR1 gene, which encodes a M{sub r} 170,000 glycoprotein that functions as a plasma membrane energy-dependent multidrug efflux pump. The authors have engineered transgenic mice that express this multidrug transporter in their bone marrow and demonstrated that these animals are resistant to leukopenia by a panel of anticancer drugs including anthracyclines, vinca alkaloids, etoposide, taxol, and actinomycin D. Differential leukocyte counts indicate that both neutrophils and lympohcytes are pretected. Drugs such as cisplatin, methotrexate, and 5-fluorouracil, which are not handled by the multidrug transporter, produce bone marrow suppression in both normal and transgenic mice. The resistance conferred by the MDR1 gene can be circumvented in a dose-dependent manner by simultaneous administration of agents previously shown to be inhibitors of the multidrug transporter in vitro, including verapamil isomers, quinidine, and quinine. They conclude that MDR1-transgenic mice provide a rapid and reliable system to determine the bioactivity of agents that reverse multidrug resistance in animals.

  14. The candidate sex-reversing DAX1 gene is autosomal in marsupials: Implications for the evolution of sex determination in mammals

    SciTech Connect (OSTI)

    Pask, A.; Toder, R.; Wilcox, S.A. [La Trobe Univ., Melbourne (Australia)] [and others] [La Trobe Univ., Melbourne (Australia); and others

    1997-05-01

    The human X-linked DAX1 gene was cloned from the region of the short arm of the human X found in duplicate in sex-reversed X{sub dup}Y females. DAX1 is suggested to be required for ovarian differentiation and to play an important role in mammalian sex determination or differentiation pathways. Its proposed dose-dependent effect on sexual development suggests that DAX1 could represent an evolutionary link with an ancestral sex-determining mechanism that depended on the dosage of an X-linked gene. Furthermore, DAX1 could also represent the putative X-linked switch gene, which independently controls sexual dimorphisms in marsupial mammals in an X-dose-dependent manner. If DAX1 has a present role in marsupial sexual differentiation or had an ancestral role in mammalian sex determination, it would be expected to lie on the marsupial X chromosome, despite the autosomal localization of other human Xp genes. We therefore cloned and mapped the DAX1 gene in the tammar wallaby (Macropus eugenii). DAX1 was located on wallaby chromosome 5p near other human Xp genes, indicating that it was originally autosomal and that it is not involved in X-linked dose-dependent sex determination in an ancestral mammal nor in marsupial sexual differentiation. 28 refs., 4 figs.

  15. Porous polymer monolithic columns with gold nanoparticles as an intermediate ligand for the separation of proteins in reverse phase-ion exchange mixed mode

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

    Terborg, Lydia; Masini, Jorge C.; Lin, Michelle; Lipponen, Katriina; Riekolla, Marja -Liisa; Svec, Frantisek

    2014-11-04

    A new approach has been developed for the preparation of mixed-mode stationary phases to separate proteins. The pore surface of monolithic poly(glycidyl methacrylate-co-ethylene dimethacrylate) capillary columns was functionalized with thiols and coated with gold nanoparticles. The final mixed mode surface chemistry was formed by attaching, in a single step, alkanethiols, mercaptoalkanoic acids, and their mixtures on the free surface of attached gold nanoparticles. Use of these mixtures allowed fine tuning of the hydrophobic/hydrophilic balance. The amount of attached gold nanoparticles according to thermal gravimetric analysis was 44.8 wt.%. This value together with results of frontal elution enabled calculation of surfacemore »coverage with the alkanethiol and mercaptoalkanoic acid ligands. Interestingly, alkanethiols coverage in a range of 4.46–4.51 molecules/nm2 significantly exceeded that of mercaptoalkanoic acids with 2.39–2.45 molecules/nm2. The mixed mode character of these monolithic stationary phases was for the first time demonstrated in the separations of proteins that could be achieved in the same column using gradient elution conditions typical of reverse phase (using gradient of acetonitrile in water) and ion exchange chromatographic modes (applying gradient of salt in water), respectively.« less

  16. Abraham Hot Springs Geothermal Area Northern Basin and Range...

    Open Energy Info (EERE)

    br Brophy br Model br Moeck br Beardsmore br Type br Volume br Geothermal br Region Mean br Reservoir br Temp br Mean br Capacity Abraham Hot Springs Geothermal Area Northern Basin...

  17. Enhancement of cancer stem-like and epithelial?mesenchymal transdifferentiation property in oral epithelial cells with long-term nicotine exposure: Reversal by targeting SNAIL

    SciTech Connect (OSTI)

    Yu, Cheng-Chia; School of Dentistry, Chung Shan Medical University, Taichung, Taiwan; Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan ; Chang, Yu-Chao; Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan

    2013-02-01

    Cigarette smoking is one of the major risk factors in the development and further progression of tumorigenesis, including oral squamous cell carcinoma (OSCC). Recent studies suggest that interplay cancer stem-like cells (CSCs) and epithelial?mesenchymal transdifferentiation (EMT) properties are responsible for the tumor maintenance and metastasis in OSCC. The aim of the present study was to investigate the effects of long-term exposure with nicotine, a major component in cigarette, on CSCs and EMT characteristics. The possible reversal regulators were further explored in nicotine-induced CSCs and EMT properties in human oral epithelial (OE) cells. Long-term exposure with nicotine was demonstrated to up-regulate ALDH1 population in normal gingival and primary OSCC OE cells dose-dependently. Moreover, long-term nicotine treatment was found to enhance the self-renewal sphere-forming ability and stemness gene signatures expression and EMT regulators in OE cells. The migration/cell invasiveness/anchorage independent growth and in vivo tumor growth by nude mice xenotransplantation assay was enhanced in long-term nicotine-stimulated OE cells. Knockdown of Snail in long-term nicotine-treated OE cells was found to reduce their CSCs properties. Therapeutic delivery of Si-Snail significantly blocked the xenograft tumorigenesis of long-term nicotine-treated OSCC cells and largely significantly improved the recipient survival. The present study demonstrated that the enrichment of CSCs coupled EMT property in oral epithelial cells induced by nicotine is critical for the development of OSCC tumorigenesis. Targeting Snail might offer a new strategy for the treatment of OSCC patients with smoking habit. -- Highlights: ? Sustained nicotine treatment induced CSCs properties of oral epithelial cells. ? Long-term nicotine treatment enhance EMT properties of oral epithelial cells. ? Long-term nicotine exposure increased tumorigenicity of oral epithelial cells. ? Si-Snail blocked xenograft tumorigenesis of long-term nicotine-treated OSCC cells.

  18. GeOx/Reduced Graphene Oxide Composite as an Anode for Li-ion Batteries: Enhanced Capacity via Reversible Utilization of Li2O along with Improved Rate Performance

    SciTech Connect (OSTI)

    Lv, Dongping; Gordin, Mikhail; Yi, Ran; Xu, Terrence (Tianren); Song, Jiangxuan; Jiang, Yingbing; Choi, Daiwon; Wang, Donghai

    2014-09-01

    A self-assembled GeOx/reduced graphene oxide (GeOx/RGO) composite, where GeOx nanoparticles were grown directly on reduced graphene oxide sheets, was synthesized via a facile one-step reduction approach and studied by X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy, electron energy loss spectroscopy elemental mapping, and other techniques. Electrochemical evaluation indicates that incorporation of reduced graphene oxide enhances both the rate capability and reversible capacity of GeOx, with the latter being due to the RGO enabling reversible utilization of Li2O. The composite delivers a high reversible capacity of 1600 mAhg-1 at a current density of 100 mAg-1, and still maintains a capacity of 410 mAhg-1 at a high current density of 20 Ag-1. Owing to the flexible reduced graphene oxide sheets enwrapping the GeOx particles, the cycling stability of the composite was also improved significantly. To further demonstrate its feasibility in practical applications, the synthesized GeOx/RGO composite anode was successfully paired with a high voltage LiNi0.5Mn1.5O4 cathode to form a full cell, which showed good cycling and rate performance.

  19. II

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

    describes the concen- 1) because control devices, such as baghouse filters and tration of hydrogen ions along a scale (from 0 to 14) that electrostatic precipitators, remove most...

  20. Continuous Emissions Monitoring System Monitoring Plan for the Y-12 Steam Plant

    SciTech Connect (OSTI)

    2003-02-28

    The Oak Ridge Y-12 National Security Complex (Y-12), managed by BWXT, is submitting this Continuous Emissions Monitoring System (CEMS) Monitoring Plan in conformance with the requirements of Title 40 of the U.S. Code of Federal Regulations (CFR) Part 75. The state of Tennessee identified the Y-12 Steam Plant in Oak Ridge, Tennessee, as a non-electrical generation unit (EGU) nitrogen oxides (NO{sub x}) budget source as a result of the NO{sub x} State Implementation Plan (SIP) under the Tennessee Department of Environment and Conservation (TDEC) Rule 1200-3-27. Following this introduction, the monitoring plan contains the following sections: CEMS details, NO{sub x} emissions, and quality assurance (QA)/quality control (QC). The following information is included in the attachments: fuel and flue gas diagram, system layout, data flow diagrams, Electronic Monitoring Plan printouts, vendor information on coal and natural gas feed systems, and the Certification Test Protocol. The Y-12 Steam Plant consists of four Wickes boilers. Each is rated at a maximum heat input capacity of 296.8 MMBtu/hour or 250,000 lb/hour of 250-psig steam. Although pulverized coal is the principal fuel, each of the units can fire natural gas or a combination of coal and gas. Each unit is equipped with a Joy Manufacturing Company reverse air baghouse to control particulate emissions. Flue gases travel out of the baghouse, through an induced draft fan, then to one of two stacks. Boilers 1 and 2 exhaust through Stack 1. Boilers 3 and 4 exhaust through Stack 2. A dedicated CEMS will be installed in the ductwork of each boiler, downstream of the baghouse. The CEMS will be designed, built, installed, and started up by URS Group, Inc. (URS). Data acquisition and handling will be accomplished using a data acquisition and handling system (DAHS) designed, built, and programmed by Environmental Systems Corporation (ESC). The installed CEMS will continuously monitor NO{sub x}, flue gas flowrate, and carbon dioxide (CO{sub 2}). The CEMS will be utilized to report emissions from each unit for each ozone season starting May 1, 2003. Each boiler has independent coal and natural gas metering systems. Coal is fed to each boiler by belt-type coal feeders. Each boiler has two dedicated coal feeders. Natural gas may be burned along with coal for flame stability. The boilers may also be fired on natural gas alone. Orifice meters measure the natural gas flow to each boiler.

  1. 3,5,4?-Trimethoxystilbene, a natural methoxylated analog of resveratrol, inhibits breast cancer cell invasiveness by downregulation of PI3K/Akt and Wnt/?-catenin signaling cascades and reversal of epithelialmesenchymal transition

    SciTech Connect (OSTI)

    Tsai, Jie-Heng; Hsu, Li-Sung; Lin, Chih-Li; Hong, Hui-Mei; Pan, Min-Hsiung; Way, Tzong-Der; Chen, Wei-Jen

    2013-11-01

    The molecular basis of epithelialmesenchymal transition (EMT) functions as a potential therapeutic target for breast cancer because EMT may endow breast tumor-initiating cells with stem-like characteristics and enable the dissemination of breast cancer cells. We have recently verified the antitumor activity of 3,5,4?-trimethoxystilbene (MR-3), a naturally methoxylated derivative of resveratrol, in colorectal cancer xenografts via an induction of apoptosis. The effect of MR-3 on EMT and the invasiveness of human MCF-7 breast adenocarcinoma cell line were also explored. We found that MR-3 significantly increased epithelial marker E-cadherin expression and triggered a cobblestone-like morphology of MCF-7 cells, while reciprocally decreasing the expression of mesenchymal markers, such as snail, slug, and vimentin. In parallel with EMT reversal, MR-3 downregulated the invasion and migration of MCF-7 cells. Exploring the action mechanism of MR-3 on the suppression of EMT and invasion indicates that MR-3 markedly reduced the expression and nuclear translocation of ?-catenin, accompanied with the downregulation of ?-catenin target genes and the increment of membrane-bound ?-catenin. These results suggest the involvement of Wnt/?-catenin signaling in the MR-3-induced EMT reversion of MCF-7 cells. Notably, MR-3 restored glycogen synthase kinase-3? activity by inhibiting the phosphorylation of Akt, the event required for ?-catenin destruction via a proteasome-mediated system. Overall, these findings indicate that the anti-invasive activity of MR-3 on MCF-7 cells may result from the suppression of EMT via down-regulating phosphatidylinositol 3-kinase (PI3K)/AKT signaling, and consequently, ?-catenin nuclear translocation. These occurrences ultimately lead to the blockage of EMT and the invasion of breast cancer cells. - Highlights: MR-3 blocked MCF-7 cell invasion by inducing a reversal of EMT. Wnt/?-catenin signaling is involved in MR-3-induced EMT reversion of MCF-7 cells. Knockdown of ?-catenin was sufficient to restore epithelial marker E-cadherin levels. MR-3 recovered the function of GSK-3? that inhibits ?-catenin nuclear translocation.

  2. Preparation of blue-emitting CaMgSi{sub 2}O{sub 6}:Eu{sup 2+} phosphors in reverse micellar system and their application to transparent emissive display devices

    SciTech Connect (OSTI)

    Choi, Sungho; Tae, Se-Won; Seo, Jung-Hyun; Jung, Ha-Kyun

    2011-06-15

    Blue-emitting Eu{sup 2+}-doped CaMgSi{sub 2}O{sub 6} phosphors were prepared by the reverse micelle method. The resultant particles were nanocrystalline with a grain size of about <300 nm and exhibited a characteristic blue emission spectrum centered at 445 nm induced by the oxygen coordinated Eu{sup 2+} ions. By using the corresponding nanophosphors followed by the formation of a uniform phosphor layer, we have demonstrated the mini-sized transparent plasma-discharge panels and investigated their luminance characteristics. Phosphor coated panel is properly transparent, {>=}65%, at the visible wavelength region and illuminates a characteristic blue emission under Ne/Xe plasma discharge conditions. Thus, we can obtain a fast decaying, robust blue-emitting silicate phosphor layer under excited plasma radiation for upcoming emissive display devices like as transparent and three-dimensional plasma display panels. - Graphical abstract: Blue-emitting CaMgSi{sub 2}O{sub 6}:Eu{sup 2+} nanophosphors coated transparent luminescent layers can be obtained. It illuminates the characteristic blue emission, spectrum centered at 425 nm wavelength, under the Ne-Xe mixed gas plasma discharge condition. Highlights: > Blue-emitting CaMgSi{sub 2}O{sub 6}:Eu{sup 2+} nanophosphors via reverse micelle method. > Transparent blue-emitting layer was prepared by using corresponding phosphors. > Fast decaying with degradation-free luminescent layer under plasma radiation. > Promising luminescent layer for the upcoming plasma discharged transparent displays.

  3. Investigating the reversibility of structural modifications of LixNiyMnzCo1-y-zO? cathode materials during initial charge/discharge, at multiple length scales

    SciTech Connect (OSTI)

    Hwang, Sooyeon; Bak, Seong -Min; Kim, Seung Min; Chung, Kyung Yoon; Chang, Wonyoung

    2015-08-11

    In this work, we investigate the structural modifications occurring at the bulk, subsurface, and surface scales of LixNiyMnzCo1-y-zO? (NMC; y, z = 0.8, 0.1 and 0.4, 0.3, respectively) cathode materials during the initial charge/discharge. Various analytical tools, such as X-ray diffraction, selected-area electron diffraction, electron energy-loss spectroscopy, and high-resolution electron microscopy, are used to examine the structural properties of the NMC cathode materials at the three different scales. Cut-off voltages of 4.3 and 4.8 V are applied during the electrochemical tests as the normal and extreme conditions, respectively. The high-Ni-content NMC cathode materials exhibit unusual behaviors, which is deviate from the general redox reactions during the charge or discharge. The transition metal (TM) ions in the high-Ni-content NMC cathode materials, which are mostly Ni ions, are reduced at 4.8 V, even though TMs are usually oxidized to maintain charge neutrality upon the removal of Li. It was found that any changes in the crystallographic and electronic structures are mostly reversible down to the sub-surface scale, despite the unexpected reduction of Ni ions. However, after the discharge, traces of the phase transitions remain at the edges of the NMC cathode materials at the scale of a few nanometers (i.e., surface scale). This study demonstrates that the structural modifications in NMC cathode materials are induced by charge as well as discharge at multiple length scales. These changes are nearly reversible after the first cycle, except at the edges of the samples, which should be avoided because these highly localized changes can initiate battery degradation.

  4. Repression of miR-17-5p with elevated expression of E2F-1 and c-MYC in non-metastatic hepatocellular carcinoma and enhancement of cell growth upon reversing this expression pattern

    SciTech Connect (OSTI)

    El Tayebi, H.M.; Omar, K.; Hegy, S.; El Maghrabi, M.; El Brolosy, M.; Hosny, K.A.; Esmat, G.; Abdelaziz, A.I.

    2013-05-10

    Highlights: The oncogenic miR-17-5p is downregulated in non-metastatic hepatocellular carcinoma patients. E2F-1 and c-MYC transcripts are upregulated in non-metastatic HCC patients. miR-17-5p forced overexpression inhibited E2F-1 and c-MYC expression in HuH-7 cells. miR-17-5p mimicking increased HuH-7 cell growth, proliferation, migration and colony formation. miR-17-5p is responsible for HCC progression among the c-MYC/E2F-1/miR-17-5p triad members. -- Abstract: E2F-1, c-MYC, and miR-17-5p is a triad of two regulatory loops: a negative and a positive loop, where c-MYC induces the expression of E2F-1 that induces the expression of miR-17-5p which in turn reverses the expression of E2F-1 to close the loop. In this study, we investigated this triad for the first time in hepatocellular carcinoma (HCC), where miR-17-5p showed a significant down-regulation in 23 non-metastatic HCC biopsies compared to 10 healthy tissues; however, E2F-1 and c-MYC transcripts were markedly elevated. Forced over-expression of miR-17-5p in HuH-7 cells resulted in enhanced cell proliferation, growth, migration and clonogenicity with concomitant inhibition of E2F-1 and c-MYC transcripts expressions, while antagomirs of miR-17-5p reversed these events. In conclusion, this study revealed a unique pattern of expression for miR-17-5p in non-metastatic HCC patients in contrast to metastatic HCC patients. In addition we show that miR-17-5p is the key player among the triad that tumor growth and spread.

  5. Evaluation of Alkali Bromide Salts for Potential Pyrochemical Applications

    SciTech Connect (OSTI)

    Prabhat K. Tripathy; Steven D. Herrmann; Guy L. Fredrickson; Tedd E. Lister; Toni Y. Gutknecht

    2013-10-01

    Transient techniques were employed to study the electrochemical behavior, reduction mechanism and transport properties of REBr3 (RE - La, Nd and Gd) in pure LiBr, LiBr-KBr (eutectic) and LiBr-KBr-CsBr (eutectic) melts. Gd(III) showed a reversible single step soluble-insoluble exchange phenomenon in LiBr melt at 973K. Although La (III), Nd(III) and Gd(III) ions showed reversible behavior in eutectic LiBr-KBr melts, these ions showed a combination of temperature dependent reversible and pseudo-reversible behavior. While both La(III) and Gd(III) showed one step reduction, the reduction of Nd(III) was observed to be a two step process. La metal could be electrodeposited from the ternary electrolyte at a temperature of 673K. Various electrochemical measurements suggest that both binary and ternary bromide melts can potentially be used to electrodeposit high purity RE metals at comparatively lower operating temperatures.

  6. Reversible photodeposition and dissolution of metal ions

    DOE Patents [OSTI]

    Foster, Nancy S. (Boulder, CO); Koval, Carl A. (Golden, CO); Noble, Richard D. (Boulder, CO)

    1994-01-01

    A cyclic photocatalytic process for treating waste water containing metal and organic contaminants. In one embodiment of the method, metal ions are photoreduced onto the photocatalyst and the metal concentrated by resolubilization in a smaller volume. In another embodiment of the method, contaminant organics are first oxidized, then metal ions removed by photoreductive deposition. The present invention allows the photocatalyst to be recycled until nearly complete removal of metal ions and organic contaminants is achieved.

  7. Reversible Sigma C-C Bond Formation

    Office of Scientific and Technical Information (OSTI)

    ... C. N.; Scott, B. L.; Da Re, R. E.; Thompson, J. D.; Kiplinger, J. L.; Morris, D. E.; ... Chem. 2007, 3151. (9) Trifonov, A. A.; Fedorova, E. A.; Fukin, G. K.; Dmzhkov, N. O.; ...

  8. Direct Imaging of Asymmetric Magnetization Reversal

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

    material like iron is itself a tiny magnet represented by a magnetic moment. If the atomic moments are pointing in random directions, they cancel each other out. So, to bring...

  9. Reversing the Circulation of Magnetic Vortices

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

    and smaller and neighboring spins would inevitably align antiparallel, they tend to tilt out of the plane, pointing either up or down. So each disk has four bits instead of...

  10. Reversing the Circulation of Magnetic Vortices

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

    materials at the nanoscale has led to the idea that these vortices can be harnessed to encode bits of information. Consumers spent 15 percent of home energy on gadgets in 2009,...

  11. Reversed flow fluidized-bed combustion apparatus

    DOE Patents [OSTI]

    Shang, Jer-Yu; Mei, Joseph S.; Wilson, John S.

    1984-01-01

    The present invention is directed to a fluidized-bed combustion apparatus provided with a U-shaped combustion zone. A cyclone is disposed in the combustion zone for recycling solid particulate material. The combustion zone configuration and the recycling feature provide relatively long residence times and low freeboard heights to maximize combustion of combustible material, reduce nitrogen oxides, and enhance sulfur oxide reduction.

  12. Reversing the Circulation of Magnetic Vortices

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

    Research funding: European Regional Development Fund, Grant Agency of the Czech Republic, and the U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES)....

  13. Reversibility and criticality in amorphous solids

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

    Regev, Ido; Weber, John; Reichhardt, Charles; Dahmen, Karin A.; Lookman, Turab

    2015-11-13

    The physical processes governing the onset of yield, where a material changes its shape permanently under external deformation, are not yet understood for amorphous solids that are intrinsically disordered. Here, using molecular dynamics simulations and mean-field theory, we show that at a critical strain amplitude the sizes of clusters of atoms undergoing cooperative rearrangements of displacements (avalanches) diverges. We compare this non-equilibrium critical behaviour to the prevailing concept of a ‘front depinning’ transition that has been used to describe steady-state avalanche behaviour in different materials. We explain why a depinning-like process can result in a transition from periodic to chaoticmore » behaviour and why chaotic motion is not possible in pinned systems. As a result, these findings suggest that, at least for highly jammed amorphous systems, the irreversibility transition may be a side effect of depinning that occurs in systems where the disorder is not quenched.« less

  14. Reversing the Circulation of Magnetic Vortices

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

    the Circulation of Magnetic Vortices Print Wednesday, 31 July 2013 00:00 In magnetic media, information is stored in binary form-one or zero, depending on which way the...

  15. Reversing the Circulation of Magnetic Vortices

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

    No other method can provide similarly comprehensive information about the fastest dynamics of magnetic states on the nanoscale. These instruments are unique and serve the whole...

  16. Shapeshifting: Reversible Shape Memory in Semicrystalline Elastomers

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Zhou J. ; Gang O. ; Turner, S. ; Brosnan, S. ; Li, Q. ; Carrillo, J. ; Nykypanchuk, D. ; Ashby, V. ; Dobrynin, A. ; Sheiko, S. Publication Date: 2014-02-25 OSTI Identifier: 1159702 Report Number(s): BNL--106077-2014-JA R&D Project: 16076; KC0403020 DOE Contract Number: DE-AC02-98CH10886 Resource Type: Journal Article Resource Relation: Journal Name: Macromolecules Research Org: Brookhaven National Laboratory (BNL) Center for Functional Nanomaterials

  17. Shapeshifting: Reversible Shape Memory in Semicrystalline Elastomers

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Zhou, J. ; Turner, S. ; Brosnan, S. ; Li, Q. ; Y. Carrillo, J. ; Nykypanchuk, D. ; Gang, O. ; Ashby, V. ; Dobrynin, A. ; Sheiko, S. Publication Date: 2014-03-11 OSTI Identifier: 1162856 Report Number(s): BNL--106802-2014-JA Journal ID: ISSN 0024--9297 DOE Contract Number: DE-AC02-98CH10886 Resource Type: Journal Article Resource Relation: Journal Name: Macromolecules; Journal Volume: 47; Journal Issue: 5 Research Org: Brookhaven National Laboratory (BNL)

  18. Reversing the Circulation of Magnetic Vortices

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

    very stable and form readily in soft magnetic materials of the sort useful for magnetic random-access memory (MRAM) devices. Interestingly, the formation of such vortices was at...

  19. Materials Data on CuW3Br7 (SG:201) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  20. Materials Data on W3Br8 (SG:64) by Materials Project

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

    Kristin Persson

    2015-03-24

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  1. Materials Data on Th6CoBr15 (SG:229) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  2. Materials Data on ThBrN (SG:129) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  3. Materials Data on CuTe2Br (SG:14) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  4. Materials Data on Tl2TeBr6 (SG:128) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  5. Materials Data on BiTeBr (SG:156) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  6. Materials Data on PaBr4 (SG:141) by Materials Project

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

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  7. Materials Data on PaBr5 (SG:14) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  8. Materials Data on Li6Br3N (SG:12) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  9. Materials Data on KAl2Br7 (SG:14) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  10. Materials Data on KPb2Br5 (SG:14) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  11. Materials Data on K2(NbBr3)3 (SG:12) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  12. Spectroscopic Evidence for a High-Spin Br-Fe(IV)-Oxo Intermediate...

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

    fungicides and antibiotics. Four classes of enzymes are now known to catalyze halogenation reactions: 1) vanadium haloperoxidases, 2) heme haloperoxidases, 3)...

  13. Tank Farm Closure & Waste Management Environmental Impact Statement <br>

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

    (DOE/EIS-0391) - Hanford Site Statements Tank Closure & WM EIS Info Documents CERCLA Five-Year Review NEPA - Categorical Exclusions NEPA - Environmental Assessments NEPA - Environmental Impact Statements Environmental Management Performance Reports Tank Farm Closure & Waste Management Environmental Impact Statement (DOE/EIS-0391) Email Email Page | Print Print Page |Text Increase Font Size Decrease Font Size The U.S. Department of Energy (USDOE) has prepared a Final Environmental

  14. Materials Data on RbBr (SG:221) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on CsBr (SG:221) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. Materials Data on PH9C3Br3N (SG:14) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  17. Materials Data on PH4Br (SG:129) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  18. Materials Data on Pd(PbBr3)2 (SG:14) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  19. Materials Data on Tl3PdBr5 (SG:61) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  20. Materials Data on Cs2SbBr6 (SG:0) by Materials Project

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

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations