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Pacific Northwest Laboratory Report on Fusion Energy Research, April 1977 - June 1977

Description: The development of economic data for fusion power plants continued in a study estimating the potential impact of a shortage of materials important in fusion plant construction. In studies developing heat transfer and fluid flow design tools for fusion reactor blankets, preconceptual design studies were initiated to identify the potential design limits of water cooling in the first wall of Tokamak Next Step (TNS) concepts. In surface effects research clean gold samples were irradiated in the Uni… more
Date: July 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stream sediment detailed geochemical survey for Marysvale, Utah

Description: Results of the Marysvale detailed geochemical survey are reported. Field and laboratory data are presented for 397 stream sediment samples and 160 radiometric readings. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. Stream sediments containing significant… more
Date: July 31, 1980
Creator: Butz, T. R.; Vreeland, J. L.; Bard, C. S.; Helgerson, R. N.; Grimes, J. G. & Pritz, P. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A bulk niobium superconducting quarter wave resonator

Description: A bath-cooled all-niobium 160 MHz quarter wave resonator prototype was constructed and tested. The objective of this research has been the development of a high performance accelerating element with {beta}{sub opt} {approx equal} 0.11 for the ALPI linac at the Laboratori Nazionali di Legnaro. The design of this resonator was based upon a previous 150 MHz model, with minor changes due to the different frequency and to modified welding procedure. An accelerating field of 5 MV/m was achieved at a … more
Date: January 1, 1990
Creator: Ben-Zvi, Ilan; Chiaveri, E.; Elkonin, B. V.; Facco, A. & Sokolowski, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal transport properties of niobium and some niobium base alloys from 80 to 1600/sup 0/K

Description: The electrical resistivities and absolute Seebeck coefficients of 99.8 at. % niobium with a RRR of 36, Nb-4.8 at. % W, Nb-5 at. % Mo, Nb-10 at. % Mo, and Nb-2.4 at. % Mo-2.4 at. % Zr were measured from 80 to 1600/sup 0/K, and the thermal conductivities of the niobium and Nb-5 at. % W were measured from 80 to 1300/sup 0/K. A technique is described for measuring the electrical resistivity and Seebeck coefficient of a specimen during radial heat flow measurements of the thermal conductivity. The t… more
Date: January 1, 1980
Creator: Moore, J. P.; Graves, R. S. & Williams, R. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Condensed-matter research at the Los Alamos pulsed neutron source (WNR)

Description: The experimental program at the WNR in condensed matter research at present is aimed principally at utilizing the high epithermal neutron flux available at a spallation neutron source. Interesting new results have been obtained in several areas including hydrogen vibrations in metals, chemical vibrational spectroscopy and the structure of liquids. For example, extensive vibrational spectra were obtained of hydrogen in Nb which could be described in terms of a three-dimensional localized anharmo… more
Date: January 1, 1982
Creator: Eckert, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simple small-polaron model for the hydrogen-concentration dependence of hydrogen diffusion in Nb

Description: We have generalized simplified small polaron models for the tunneling of interstitials in solids to include interactions between the diffusing particles. This is applied to the calculation of the average hopping rate of hydrogen in Niobium as a function of hydrogen concentration for small concentrations, i.e. for an H/Nb ratio (c) of .06 or less. The hopping of a single H under the influence of nearby, stationary H's was treated. The interactions between interstitials include a hard-core repuls… more
Date: January 1, 1982
Creator: Tonks, D.L. & Silver, R.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermoelectric effect in a nonequilibrium superconductor

Description: Initial results are reported showing experimental evidence for a pair-quasiparticle electrochemical potential difference in a superconductor in a temperature gradient. This potential diverges at low temperature and, within the resolution of the data, seems to approach a constant value at T/sub c/. The data can be used to extract a value for the thermal transport current of normal excitations in the superconductor.
Date: January 1, 1977
Creator: Falco, C.M.
Item Type: Refine your search to only Article
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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Scattering of phonons by dislocations

Description: By 1950, an explicit effort had been launched to use lattice thermal conductivity measurements in the investigation of defect structures in solids. This technique has been highly successful, especially when combined with the measurements of other properties such as optical absorption. One exception has been the study of dislocations. Although dislocations have a profound effect on the phonon thermal conductivity, the mechanisms of the phonon-dislocation interaction are poorly understood. The mo… more
Date: January 1, 1979
Creator: Anderson, A. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Concentration profile of hydrogen near the surface of niobium

Description: Samples hydrided in two different ways were investigated. The materials used were thin foils (50 ..mu..m, MARZ grade) of niobium, 10 x 25 mm in size. The two methods of hydriding produced different surface conditions which were the subject of the present investigation. One method consisted of the following procedures. The samples were outgassed and cleaned in UHV to remove virtually all the interstitial impurities from the bulk and surface. A small spot of Pd was then deposited onto the clean s… more
Date: January 1, 1982
Creator: Pick, M. A.; Hanson, A.; Jones, K. W. & Goland, A. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Irradiation testing of a niobium-molybdenum developmental thermocouple

Description: A need exists for a radiation-resistant thermocouple capable of monitoring temperatures in excess of the limits of the chromel/alumel system. Tungsten/rhenium and platinum/rhodium thermocouples have sufficient temperature capability but have proven to be unstable because of irradiation-induced decalibration. The niobium/molybdenum system is believed to hold great potential for nuclear applications at temperatures up to 2000 K. However, the fragility of pure niobium and fabrication problems with… more
Date: October 1, 1991
Creator: Knight, R. C. & Greenslade, D. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Metallurgy of continuous filamentary A15 superconductors

Description: The early history of the bronze process is recapitulated and modifications to the process which have since followed are described. The metallurgical principles, which are involved in the process, are described including the kinetics of the compound growth, the effects of additives on the growth, etc. The superconducting properties of these compounds are also discussed. The influence of metallurgical variables on the superconducting properties is discussed in detail. In discussing the supercondu… more
Date: January 1, 1980
Creator: Suenaga, M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ITER divertor sputtering erosion -- recent analysis for carbon, beryllium, tungsten, and niobium surfaces

Description: ITER divertor plate sputtering erosion has been analyzed using current design information and updated impurity transport models. The REDEP erosion/redeposition code was used to compute erosion for a very low plasma divertor temperature (T{sub e{sub 0}} {approx} 12 eV) physics phase reference'' case, and for other plasma conditions. A high surface temperature case (T{sub s{sub 0}} = 1800{degree}C) is analyzed for a carbon surface. Niobium is analyzed using WBC near-surface transport code results… more
Date: July 1, 1991
Creator: Brooks, J. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of Electron and UV Photon Surface Interactions. Progress Report, March 1, 1977--February 28, 1978

Description: Considerable data on ESD from 304 stainless steel have been obtained. Cross sections as a function of bombarding electron energy, surface temperature, desorbing species, etc. are now available. Energy distributions of desorbing ions have also been tabulated. It is interesting to note that regardless of sample material and sample preparation H/sup +/ and F/sup +/ were always predominant ESD species. Electron induced dissociation of metal oxides, noted during AES measurements, has been studied fo… more
Date: November 1, 1977
Creator: Lichtman, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal desorption spectroscopy (TDS) of hydrogen from niobium

Description: Thermal desorption spectroscopy is often used to determine the activation energy of desorption of an adsorbate on a substrate as well as the order of the kinetics. In the case of flash desorption of an adsorbate from a surface obeying second order kinetics, a plot of Log(theta/sub o/T/sub p//sup 2/) vs 1/T/sub p/ (where theta/sub o/ is the initial surface coverage and T/sub P/ is the temperature of the maximum desorption rate, i.e., the desorption temperature) will yield a straight line, the sl… more
Date: January 1, 1982
Creator: Ghosh, V.J.; Pick, M.A.; Welch, D.O. & Dienes, G.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Interfacial fracture toughness of alumina/niobium systems

Description: The interfacial fracture toughness of an alumina/niobium composite has been measured as a function of phase angle. The interface was formed by solid-state bonding bulk Coor's AD-999 fine-grain alumina with a commercial purity niobium at 1600{degrees}C for 0.5 hr under a pressure of 10.5 MPa. The alumina/niobium system has a number of features which makes it ideal for an investigation of interfacial fracture toughness. From HREM data we estimate that the width of the interface is no more than 10… more
Date: January 1, 1991
Creator: Stout, M.G. (Los Alamos National Lab., NM (United States)); O'Dowd, N.P. & Shih, C.F. (Brown Univ., Providence, RI (United States). Div. of Engineering)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quality engineering and control. Semiannual progress report, November-December 1978, January-April 1979. [PCB]

Description: This document reports the following: atomic absorption spectroscopy of Ir in Pu-Ir alloys; removal of Pu from soil; surface microanalysis using elemental x-ray mapping; microscopic scanning of Ga in Pu; microscopy of defects in Pu; emission spectroscopy of Ir and Y in PuO/sub 2/; gas chromatograhy of PCB's in transformer oils and water; liquid chromatography of chlorophenoxy acid herbicides in water; solution analysis by spark source mass spectrometry; a portable gas sampling system; flamm… more
Date: August 2, 1980
Creator: Carpenter, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Condensed Matter at High Shock Pressures

Description: Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N/sub 2/, CO, SiO/sub 2/-aerogel, H/sub 2/O, and C/sub 6/H/sub 6/. The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in ter… more
Date: July 12, 1985
Creator: Nellis, W. J.; Holmes, N. C.; Mitchell, A. C.; Radousky, H. B. & Hamilton, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Soft-sphere model for liquid metals

Description: A semi-empirical soft-sphere model of fluids is modified for application to the thermodynamic properties of liquid metals. Enthalpy, volume, and sound speed are computed as functions of temperature for 13 metals and compared with experimental data. Critical points and coexistence curves are also computed and compared with experimental data, where these have been measured. Strengths and weaknesses of the model are discussed.
Date: November 8, 1977
Creator: Young, D.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dislocation sweeping of defects in neutron- and electron-irradiated niobium

Description: The glide of dislocations in a (441)-oriented Nb single crystal irradiated at 325 K with 5.5 x 10/sup 21/ neutrons/m/sup 2/ (E > 0.1 MeV) is shown for increasing time of tensile elongation (2 x 10/sup -4/ mm/s) in the High Voltage Electron Microscope at Argonne National Laboratory. The dimensions of the tensile specimen in the guage length were approximately 2 mm x 0.5 mm x 0.0001 mm. An electron energy of 900 keV was used during the simultaneous deformation and TEM observation.
Date: October 1, 1983
Creator: Loomis, B. A. & Otero, M. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Metabolic and environmental aspects of fusion reactor activation products: niobium

Description: A summary of the metabolic and environmental aspects of niobium is presented. The toxicological symptoms from exposure to niobium are given, along with lethal concentration values for acute and chronic exposures. Existing human data are presented; animal uptake and retention data are analyzed for various routes of administration. Recommended metabolic values are also presented along with comments concerning their use and appropriateness. The natural distribution of niobium is given for freshwat… more
Date: November 1, 1977
Creator: Easterly, C.E. & Shank, K.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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