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Realtime structural electrochemistry of platinum clusters using dispersive XAFS

Description: Chemical reference tables state that the standard potential for the reaction of Pt with water, Pt + 2H{sub 2}O {r_arrow} Pt(OH){sub 2} + 2H{sup +} + 2e{sup {minus}}, is 0.98 V, and electrochemical studies propose that this reaction may occur at potentials as low as 0.8 V. Using dispersive x-ray absorption fine-structure (XAFS) spectroscopy, the authors have directly probed the structural evolution of a Pt catalyst operating in-situ in a polymer electrolyte fuel cell during cyclic voltammetry. T… more
Date: December 31, 1993
Creator: Allen, P. G.; Conradson, S. D.; Wilson, M. S.; Gottesfeld, S. & Raistrick, I. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The solubility of hydrogen in plutonium in the temperature range 475 to 825 degrees centigrade

Description: The solubility of hydrogen (H) in plutonium metal (Pu) was measured in the temperature range of 475 to 825{degree}C for unalloyed Pu (UA) and in the temperature range of 475 to 625{degree}C for Pu containing two-weight-percent gallium (TWP). For TWP metal, in the temperature range 475 to 600{degree}C, the saturated solution has a maximum hydrogen to plutonium ration (H/Pu) of 0.00998 and the standard enthalpy of formation ({Delta}H{degree}{sub f(s)}) is (-0.128 {plus minus} 0.0123) kcal/mol. Th… more
Date: January 1, 1991
Creator: Allen, Thomas H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rational economic strategy and entropic analysis

Description: The neglect of entropic changes of energy and matter in the economic process leads to incorrect formulation of economic theory, as was first pointed out by the economist, Nicholas Georgescu-Roegen. Entropic analysis, that is, the reckoning of entropic changes in real-world processes, appears to be a useful guide toward a realistic understanding of the economic process. The example chosen here is the choice between natural gas and coal as fossil fuel. An outline of the necessary analysis is disc… more
Date: January 1, 1978
Creator: Allred, J.C. & Howard, H.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reactive sintering of TiAl–Ti5Si3 in situ composites

Description: TiAl with between 0 and 20 vol%Ti5Si3 was produced by reactive sintering (700 °C for 15 min in vacuum) of cold pressed compacts of elemental Ti, Al and Si powder. The results show that adding Si to Ti and Al reduces the swelling associated with reactive sintering of TiAl, as composites containing more than 5 vol%Ti5Si3 densified during reactive sintering. However, composites containing more than 10 vol%Ti5Si3 did not retain their shape and the TiAl+20 vol%Ti5Si3 composite completely melted duri… more
Date: June 1, 2005
Creator: Alman, David E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A High-Efficiency Positive (Negative) Surface Ionization Source for Rib Generation

Description: A versatile, new concept, spherical-geometry, positive (negative) surface-ionization source has been designed and fabricated which will have the capability of generating both positive- and negative-ion beams without mechanical changes to the source. The source utilizes a highly permeable, high-work-function Ir ionizer ({phi} {congruent} 5. 229 eV) for ionizing highly electropositive atoms/molecules; while for negative-surface ionization, the work function is lowered to {phi} {congruent} 1.43 eV… more
Date: December 31, 1995
Creator: Alton, G. D. & Mills, G. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal/chemical degradation of ceramic cross-flow filter materials

Description: This report summarizes the 14-month, Phase 1 effort conducted by Westinghouse on the Thermal/Chemical Degradation of Ceramic Cross-Flow Filter Materials program. In Phase 1 expected filter process conditions were identified for a fixed-bed, fluid-bed, and entrained-bed gasification, direct coal fired turbine, and pressurized fluidized-bed combustion system. Ceramic cross-flow filter materials were also selected, procured, and subjected to chemical and physical characterization. The stability of… more
Date: November 1, 1989
Creator: Alvin, M. A.; Lane, J. E. & Lippert, T. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Calculation of Properties of Gases at High Temperatures

Description: "The role of the potential of intermolecular force in determining properties of gases at elevated temperatures is discussed. Coefficients of viscosity and self diffusion, isotopic reduced thermal diffusion ratios, and second virial coefficients for helium, argon, and nitrogen at 1,000, 5,000, and 15,000 d K were calculated from extrapolated potentials and from beam potentials."
Date: unknown
Creator: Amdur, I. & Ross, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Calculation of Properties of Gases at High Temperatures. Technical Report No. 2

Description: The role of the potential of intermolecular force in determining properties of gases at elevated temperatures is discussed. Coefficients of viscosity and selfdiffusion, isotopic reduced themaal diffusion ratios, and second virial cofficients for helium, argon, and nitrogen at 1,000, 5,000, and 15,000 d K were calculated from extrapolated potentials and from beam potentials. (W.D.M.)
Date: August 1, 1958
Creator: Amdur, I. & Ross, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ames Laboratory Annual Summary Research Report in Metallurgy: 1960

Description: Annual summary documenting research related to metallurgy at Ames Laboratory. Discussions are given of developments in the following areas: the preparation and purification of metals; phase equlibria and thermodynamic properties of alloys; physical and mechanical properties of metals and alloys; solid state studies; separation processes; and investigations dealing with diffusion, oxidation, and reduction, halide reactions, preparations, vapor pressure measurements, and transport reactions. (B.… more
Date: December 1960
Creator: Ames Laboratory
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Prediction of Corrosion of Advanced Materials and Fabricated Components

Description: The goal of this project is to provide materials engineers, chemical engineers and plant operators with a software tool that will enable them to predict localized corrosion of process equipment including fabricated components as well as base alloys. For design and revamp purposes, the software predicts the occurrence of localized corrosion as a function of environment chemistry and assists the user in selecting the optimum alloy for a given environment. For the operation of existing plants, the… more
Date: September 29, 2007
Creator: Anderko, A.; Engelhardt, G.; Lencka, M. M.; Jakab, M. A.; Tormoen, G. & Sridhar, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemistry, phase formation, and catalytic activity of thin palladium-containing oxide films synthesized by plasma-assisted physical vapor deposition

Description: The chemistry, microstructure, and catalytic activity of thin films incorporating palladium were studied using scanning and transmission electron microscopies, X-ray diffraction, spectrophotometry, 4-point probe and catalytic tests. The films were synthesized using pulsed filtered cathodic arc and magnetron sputter deposition, i.e. techniques far from thermodynamic equilibrium. Catalytic particles were formed by thermally cycling thin films of the Pd-Pt-O system. The evolution and phase formati… more
Date: November 26, 2010
Creator: Anders, Andre
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Metal Plasmas for the Fabrication of Nanostructures

Description: A review is provided covering metal plasma production, theenergetic condensation of metal plasmas, and the formation ofnanostructures using such plasmas. Plasma production techniques includepulsed laser ablation, filtered cathodic arcs, and various forms ofionized physical vapor deposition, namely magnetron sputtering withionization of sputtered atoms in radio frequency discharges,self-sputtering, and high power impulse magnetron sputtering. Thediscussion of energetic condensation focuses on th… more
Date: September 21, 2006
Creator: Anders, Andre
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fluorine for Hydrogen Exchange in the Hydrofluorobenzene Derivatives C6HxF(6-x), where x = 2, 3, 4 and 5 by Monomeric [1,2,4-(Me3C)3C5H2]2CeH; The Solid State Isomerization of [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,5-C6HF4) to [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,6-C6HF4)

Description: The reaction between monomeric bis(1,2,4-tri-t-butylcyclopentadienyl)cerium hydride, Cp'2CeH, and several hydrofluorobenzene derivatives is described. The aryl derivatives that are the primary products, Cp'2Ce(C6H5-xFx) where x = 1,2,3,4, are thermally stable enough to be isolated in only two cases, since all of them decompose at different rates to Cp'2CeF and a fluorobenzyne; the latter is trapped by either solvent when C6D6 is used or by a Cp'H ring when C6D12 is the solvent. … more
Date: April 21, 2008
Creator: Andersen, Richard; Werkema, Evan L. & Andersen, Richard A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of a carburizing and quenching simulation tool: numerical simulations of rings and gears

Description: The ability to accurately calculate temperatures, stresses and metallurgical transformations in a single calculation or in a sequence of calculations is the key to prediction of distortion, residual stress and phase distribution in quench hardened automotive parts. Successful predictions in turn rely on the adequacy of the input data to the calculational procedure. These data include mechanical and thermal properties of the alloy phases over the range of temperature and strain rates experienced… more
Date: October 1, 1996
Creator: Anderson, C.; Godlman, P. & Rangaswamy, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of improved cathodes for solid oxide fuel cells. Final report

Description: The University of Missouri-Rolla conducted a 17 month research program focused on the development and evaluation of improved cathode materials for solid oxide fuel cells (SOFC). The objectives of this program were: (1) the development of cathode materials of improved stability in reducing environments; and (2) the development of cathode materials with improved electrical conductivity. The program was successful in identifying some potential candidate materials: Air sinterable (La,Ca)(Cr,Co)O{su… more
Date: March 1, 1991
Creator: Anderson, H. U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of improved cathodes for solid oxide fuel cells

Description: The University of Missouri-Rolla conducted a 17 month research program focused on the development and evaluation of improved cathode materials for solid oxide fuel cells (SOFC). The objectives of this program were: (1) the development of cathode materials of improved stability in reducing environments; and (2) the development of cathode materials with improved electrical conductivity. The program was successful in identifying some potential candidate materials: Air sinterable (La,Ca)(Cr,Co)O{su… more
Date: March 1, 1991
Creator: Anderson, H.U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transient Analysis of Two-Phase Natural-Circulation Systems

Description: The design of high-performance natural-circulation boiling systems requires that the behavior of the systems be characterized under transient conditions. In order to accomplish this, the time- and space-dependent continuity, energy, and momentum equations for a natural-circulation system are written. This publication presents a technique for solving the equations of a natural-circulation system. The solutions are compared with experimental results at various pressures with two geometries in boi… more
Date: December 1, 1962
Creator: Anderson, R. P.; Bryant, L. T.; Carter, J. C. & Marchaterre, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Future CIS Manufacturing Technology Development: Final Report, 8 July 1998--17 October 2001

Description: The University of Florida served as the basis for educating 12 graduate students in the area of photovoltaics engineering and research with a focus on thin-film CIS manufacturing technologies. A critical assessment of the thermodynamic data and of the phase diagrams for the Cu-Se and In-Se binary systems were carried out. We investigated the use of two novel precursor structures that used stacked In-Se and Cu-Se binary layers instead of conventional elemental layers, followed by rapid thermal p… more
Date: June 1, 2003
Creator: Anderson, T. J.; Crisalle, O. D.; Li, S. S. & Holloway, P. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fundamental Materials Research and Advanced Process Development for Thin-Film CIS-Based Photovoltaics: Final Technical Report, 2 October 2001 - 30 September 2005

Description: The objectives for this thin-film copper-indium-diselenide (CIS) solar cell project cover the following areas: Develop and characterize buffer layers for CIS-based solar cell; grow and characterize chemical-bath deposition of Znx Cd1-xS buffer layers grown on CIGS absorbers; study effects of buffer-layer processing on CIGS thin films characterized by the dual-beam optical modulation technique; grow epitaxial CuInSe2 at high temperature; study the defect structure of CGS by photoluminescence spe… more
Date: September 1, 2006
Creator: Anderson, T. J.; Li, S. S.; Crisalle, O. D. & Craciun, V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Performance of 110-millimeter-bore M-1 tool steel ball bearings at high speeds, loads, and temperatures

Description: Report presenting eleven 110-millimeter-bore ball thrust bearings made of M-1 tool steel were operated over a range of DN values at mean outer-race temperatures to 678 degrees Fahrenheit. Testing occurred at a variety of thrust loads, radial loads, oil flows, and oil inlet temperatures. Results regarding the difference between tests without heat addition and tests with heat addition, fatigue failures, performance of cage materials, and oil-interruption tests are provided.
Date: January 1957
Creator: Anderson, William J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparing FRACHEM and TOUGHREACT for reactive transport modelingof brine-rock interactions in enhanced geothermal systems (EGS)

Description: Coupled modelling of fluid flow and reactive transport ingeothermal systems is challenging because of reservoir conditions such ashigh temperatures, elevated pressures and sometimes high salinities ofthe formation fluids. Thermal hydrological-chemical (THC) codes, such asFRACHEM and TOUGHREACT, have been developed to evaluate the long-termhydrothermal and chemical evolution of exploited reservoirs. In thisstudy, the two codes were applied to model the same geothermal reservoir,to forecast reser… more
Date: November 15, 2005
Creator: Andre, L.; Spycher, N.; Xu, T.; Pruess, K. & Vuataz, F.-D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling Brine-Rock Interactions in an Enhanced Geothermal System Deep Fractured Reservoir at Soultz-Sous-Forets (France) - A Joint Approach Using Two Geochemical Codes: Frachem and Toughreact

Description: The modeling of coupled thermal, hydrological, and chemical (THC) processes in geothermal systems is complicated by reservoir conditions such as high temperatures, elevated pressures and sometimes the high salinity of the formation fluid. Coupled THC models have been developed and applied to the study of enhanced geothermal systems (EGS) to forecast the long-term evolution of reservoir properties and to determine how fluid circulation within a fractured reservoir can modify its rock properties.… more
Date: December 31, 2006
Creator: Andre, Laurent; Spycher, Nicolas; Xu, Tianfu; Vuataz, Francois-D. & Pruess, Karsten
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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