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Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces

Description: We have measured the cross sections for x-ray photoelectron-induced desorption of hydrogen ions from beryllium, carbon, aluminum, tantalum, and gold surfaces. This report describes the results of the cross-section measurements, and discusses a time-of-flight technique that allows the determination of ionic-desorption cross sections as small as 10/sup -25/ cm/sup 2/ per photoelectron. 19 refs., 7 figs.
Date: September 20, 1985
Creator: Kinney, J. H.; Siekhaus, W. J. & Anderson, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Long-lived heavy mass elements half-lives (A > 125)

Description: Reported values of half-lives of intermediate mass and heavy elements are evaluated. The evaluation analysis estimates the systematic error the resulting standard deviation. Recommended values are then presented for /sup 128/Te, /sup 130/Te, /sup 129/I, /sup 138/La, /sup 144/Nd, /sup 145/Nd, /sup 146,147,148/Sm, /sup 152/Gd, /sup 154/Dy, /sup 176/Lu, /sup 174/Hf, /sup 180/Ta, /sup 187/Re, /sup 186/Os, /sup 190/Pt, /sup 204,205/Pb, and /sup 230,232/Th. 103 refs., 21 tabs. (WRF)
Date: January 1, 1985
Creator: Holden, Norman E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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RIMS diagnostics for laser desorption/laser ablation

Description: Laser desorption mass spectrometry is a useful method for interrogating materials and events at or near surfaces. Laser desorption/ablation combined with Resonance Ionization Mass Spectrometry (RIMS) provides a powerful tool to obtain information on chemical composition and speciation and, in some cases, internal and translational energy distributions. The application of this technique to the interrogation of materials and interfaces is discussed for several systems, including the analysis of c… more
Date: January 1, 1986
Creator: Apel, E. C.; Nogar, N. S.; Miller, C. M. & Estler, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, January 1, 1980-March 31, 1980

Description: Results are presented of work performed on the Advanced Gas-Cooled Nuclear Reactor Materials Evaluation and Development Program. The objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical prope… more
Date: June 25, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resonance ionization mass spectrometry at Los Alamos National Laboratory

Description: Two approaches to RIMS will be discussed here. The first is the use of continuous-wave (cw) dye lasers as the ionization source. Continuous excitation effectively matches the ionization to the evaporation of sample from a resistively heated filament, providing for efficient use of the sample. In addition, cw ionization permits pulse counting detection, necessary for the measurement of large isotope ratios on small samples. In the cases of lutetium and technetium discussed below, average ionizat… more
Date: January 1, 1986
Creator: Miller, C. M.; Nogar, N. S.; Apel, E. C. & Downey, S. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Light-particle emission as a probe of the rotational degrees of freedom in deep-inelastic reactions

Description: The emission of alpha particles in coincidence with the most deeply inelastic heavy-ion reactions has been studied for /sup 181/Ta/sup +/ /sup 165/Ho at 1354 MeV laboratory energy and /sup nat/Ag + /sup 84/Kr at 664 MeV. Alpha particle energy spectra and angular distributions, in coincidence with a projectile-like fragment, were acquired both in the reaction plane and out of the reaction plane at a fixed in-plane angle. The in-plane data for both systems are employed to show that the bulk of th… more
Date: May 1, 1982
Creator: Sobotka, L.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High temperature fuel cell research and development. Final technical status report, 1 March 1979-31 March 1980. [Molten carbonate fuel cells]

Description: The objective of the program has been to evaluate potential materials for their chemical and physical stability in molten carbonate fuel cell electrolyte. Eleven powdered candidate materials were selected based on previous physical and chemical stability tests at elevated temperatures on solid materials and/or their thermodynamic stability with respect to proposed degradation reactions. The eleven candidate materials, plus gamma lithium aluminate, were characterized prior to corrosion testing u… more
Date: May 1, 1980
Creator: Lessing, P.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Liquid-metal embrittlement of refractory metals by molten plutonium

Description: Embrittlement by molten plutonium of the refractory metals and alloys W-25 wt % Re, tantalum, molybdenum, and Ta-10 wt % W was studied. At 900/sup 0/C and a strain rate of 10/sup -4/ s/sup -1/, the materials tested may be ranked in order of decreasing susceptibility to liquid-plutonium embrittlement as follows: molybdenum, W-25 wt % Re, Ta-10 wt % W, and tantalum. These materials exhibited a wide range in susceptibility. Embrittlement was found to exhibit a high degree of temperature and strain… more
Date: July 1, 1980
Creator: Lesuer, D. R.; Bergin, J. B.; McInturff, S. A. & Kuhn, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sb interactions with TaC precipitates and Cu in ion-implanted. cap alpha. -Fe

Description: The interactions of Sb with the other species implanted into Fe to form Fe-Ta-C-Sb and Fe-Cu-Sb alloys have been examined with transmission electron microscopy and Rutherford backscattering following annealing at 873/sup 0/K. Trapping of Sb at TaC precipitates is observed in the former alloy just as was previously observed in Fe-Ti-C-Sb. In Fe-Cu-Sb, Sb interactions are governed by the atomic ratio of Sb to Cu. For ratios between 0.2 to 0.4, the compound ..beta..-Cu/sub 3/Sb was observed to for… more
Date: January 1, 1980
Creator: Follstaedt, D. M. & Myers, S. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fuel systems for compact fast space reactors

Description: About 200 refractory metal clad ceramic fuel pins have been irradiated in thermal reactors under the 1200 K to 1550 K cladding temperature conditions of primary relevance to space reactors. This paper reviews performance with respect to fissile atom density, operating temperatures, fuel swelling, fission gas release, fuel-cladding compatibility, and consequences of failure. It was concluded that UO/sub 2/ and UN fuels show approximately equal performance potential and that UC fuel has lesser po… more
Date: December 1, 1983
Creator: Cox, C.M.; Dutt, D.S. & Karnesky, R.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal Conductivity of Quasi-One Dimensional Conductors

Description: The thermal conductivity of K{sub 0.3}M{sub 0}O{sub 3}, (TaSe{sub 4}){sub 2}I and TaS{sub 3} have been studied. Together with the specific heat measurement, the anomaly observed in thermal conductivity around the Peierls transition is believed to be due to extra heat carried by the 2k{sub F} soft phonons. The field dependent thermal conductivity of the blue bronze and TaS{sub 3} have also been measured by two distinct methods, and found to be independent of applied electric field. 17 refs., 3 f… more
Date: January 1, 1989
Creator: Kwok, R.S. (California Univ., Los Angeles, CA (USA). Dept. of Physics) & Brown, S.E. (Los Alamos National Lab., NM (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Production of high energy density in anti N-nucleus interactions

Description: The results of an investigation of anti p- (and to a lesser extent) anti d- nucleus interactions are reported. The technique involves following the classical production and propagation of mesons (..pi..,K/sup +/, K/sup 0/, K/sup -/, K/sup 0/, K*, eta, ..omega.., phi) and baryons (N,..lambda..,..sigma..) in nuclei after antiparticle annihilation. It is found that small regions of the nucleus can be raised to sufficiently high energy densities that some predictions of a quark-gluon phase transiti… more
Date: January 1, 1986
Creator: Gibbs, W.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Survey of physical property data for several alloys. [Nitronic 33; copper C10400; copper C17510]

Description: This report summarizes an examination of physical property data available in the literature for six alloys of potential interest to the Toroidal Fusion Core Experiment in the Fusion Energy Program. The properties of thermal expansion, density, specific heat, electrical resistivity, and thermal conductivity were compiled for six alloys: Nitronic 33, a low-nickel, high manganese stainless steel; nickel-base Inconnel Alloys 625, 718, and X-750; and copper alloys C10400 and C17510. The temperatures… more
Date: August 1, 1985
Creator: Pawel, R. E. & Williams, R. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Uranium hydrogeochemical and stream sediment reconnaissance data release for the Elk City NTMS Quadrangle, Idaho/Montana, including concentrations of forty-five additional elements

Description: Totals of 1580 water and 1720 sediment samples were collected from 1754 locations in the quadrangle. Elemental concentration, field measurement, weather, geologic, and geographic data for each sample location are listed for waters in Appendix I-A and for sediments in Appendix I-B. Uranium/thorium ratios for sediment samples are also included in Appendix I-B. All elemental analyses were performed at the LASL. Water samples were initially analyzed for uranium by fluorometry. All water samples con… more
Date: July 1, 1980
Creator: Broxton, D. E. & Beyth, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Engineering data bases for refractory alloys

Description: Refractory alloys based on niobium, molybdenum, tantalum, and tungsten are required for the multi-100kW(e) space nuclear reactor power concepts that have been assessed in the SP-100 Program because of the extremely high temperatures involved. A review is presented of the technology efforts on the candidate refractory alloys in the areas of availability/fabricability, mechanical properties, irradiation effects, and compatibility. Of the niobium-base alloys, only Nb-1Zr has a data base that is su… more
Date: January 1, 1985
Creator: Cooper, R.H. Jr. & Harms, W.O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Production of slow-positron beams with an electron linac

Description: Intense, pulsed beams of low-energy positrons have been produced by a high-energy beam from an electron linac. The production efficiency for low-energy positrons has been determined for electrons with 60 to 120 MeV energy, low-energy positron beams from a linac can be of much higher intensity than those beams currently derived from radioactive sources.
Date: March 26, 1982
Creator: Howell, R. H.; Alvarez, R. A. & Stanek, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spallation target-moderator-reflector studies at the Weapons Neutron Research facility. [800-MeV p]

Description: Basic neutronics data, initiated by 800-MeV proton spallation reactions, are important to spallation neutron source development and electronuclear fuel production. Angle-dependent and energy-dependent neutron production cross sections, energy-dependent and total neutron yields, thermal and epithermal neutron surface and beam fluxes, and fertile-to-fissile conversion ratios are being measured. The measurements are being done at the Weapons Neutron Research facility on a variety of targets and ta… more
Date: January 1, 1980
Creator: Russell, G. J.; Gilmore, J. S.; Prael, S. D.; Robinson, H. & Howe, S. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermodynamics of the tantalum-carbon-chlorine-hydrogen system applied to the CVD of carbide/carbon composite materials

Description: Complex equilibrium thermodynamic calculations using the computer code SOLGASMIX-PV were performed for the Ta-Cl-H and Ta-C-Cl-H systems in order to evaluate the chemistry associated with the chemical vapor deposition of Ta, Ta/sub 2/C, and TaC on graphite yarn and woven structures. Results of the thermodynamic calculations were compared with coated materials prepared by hydrogen reduction of TaCl/sub 5/(g) and C/sub 3/H/sub 6/(g) between 1025 and 1223/sup 0/K using a variety of reaction gas co… more
Date: April 1, 1980
Creator: Behrens, R. G.; Newkirk, L. R. & Wallace, T. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ferroelectric ceramics for dielectric power conversion. Annual report, March 1, 1979-April 30, 1980

Description: Materials selected for study were those which could be expected to have useful Curie temperatures, resistivities, coercive fields, and Devonshire coefficients. Materials studied include PZT (lead-zirconia-titania system), Bi(Na,K)Ti/sub 2/O/sub 6/, rare earth titanoniobates, other tantalates and niobates, and thin films. Graphs are given for spontaneous polarization as a function of composition, temperature dependence of spontaneous polarization and coercive field for modified PSZT dielectrics,… more
Date: May 1, 1980
Creator: Payne, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research Toward New Alloys for Generator Retaining Rings

Description: The research reported here was undertaken to develop an alloy suitable for use in the retaining rings of two-pole electrical generators that would have three key properties: a yield strength of 200 ksi or greater with good residual toughness; resistance to hydrogen embrittlement and stress-corrosion cracking; and processability through heat treatment after hot forming, to avoid the necessity of cold forming of the ring. The principal alloy developed during the course of this work was an iron-ba… more
Date: November 1, 1981
Creator: Morris, J. W., Jr. & Chang, K. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Case history of tantalum-weld cracking

Description: Tantalum welding is normally a routine operation. Of course, the routine involves careful cleaning beforehand, and welding in an atmosphere which excludes reactive gases (O/sub 2/, N/sub 2/, H/sub 2/). Recently a weld cracking problem was encountered at SNLA despite the fact that normal precautions had been taken. This account reviews what happened, the analytical procedures followed to determine the unusual source of the problem, and the remedy which solved the problem.
Date: January 1, 1982
Creator: Knorovsky, G.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low temperature CVD of TaB/sub 2/

Description: Crystalline TaB/sub 2/ has been deposited using the CVD reaction of TaCl/sub 5/ and B/sub 2/H/sub 6/ in the temperature range of 773-1200/sup 0/K. Thermodynamic calculations have been made which compare the use of both B/sub 2/H/sub 6/ and BCl/sub 3/ as B source gases. The deposits obtained with B/sub 2/H/sub 6/ exhibited extremely small crystal size and contained amorphous B when the deposition temperature was below approx. 873/sup 0/K but were substoichiometric in B above this temperature. Ca… more
Date: January 1, 1980
Creator: Randich, E.
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Partner: UNT Libraries Government Documents Department
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Electron energy and charge albedos - calorimetric measurement vs Monte Carlo theory

Description: A new calorimetric method has been employed to obtain saturated electron energy albedos for Be, C, Al, Ti, Mo, Ta, U, and UO/sub 2/ over the range of incident energies from 0.1 to 1.0 MeV. The technique was so designed to permit the simultaneous measurement of saturated charge albedos. In the cases of C, Al, Ta, and U the measurements were extended down to about 0.025 MeV. The angle of incidence was varied from 0/sup 0/ (normal) to 75/sup 0/ in steps of 15/sup 0/, with selected measurements at … more
Date: November 1, 1981
Creator: Lockwood, G. J.; Ruggles, L. E.; Miller, G. H. & Halbleib, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermodynamic study of the MWG system/components and measurement of the oxygen partial pressure in the heat source capsule

Description: A thermodynamic study of the Milliwatt Generator heat source capsule was performed to determine the effects of the oxide fuel on container materials at elevated temperatures in order to evaluate the factors affecting embrittlement of T-111 alloy. The study indicates that relatively slow oxidation of the T-111 of the capsule occurs during pretreatment. Yttrium added to the /sup 238/PuO/sub 2/ fuel charge is functioning in its designed role as an oxygen getter and is stabilizing at an O/Pu ratio … more
Date: June 23, 1980
Creator: David, D.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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