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Correlation of alluvial deposits at the Nevada Test Site

Description: Because characteristics of rock layers and problems in drilling must be studied before radioactive waste can be safely contained, an evaluation was made of methods for correlating alluvial deposits at Yucca Flat of the Nevada Test Site (NTS). Although correlation of Tertiary volcanic tuff beds at the NTS has been successfully achieved, correlation of stratigraphic zones in the overlying alluvium has posed technical difficulties. We have evaluated several methods for correlating alluvial deposit… more
Date: September 30, 1977
Creator: Grothaus, B. & Howard, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Electrical Resistivity of Molten and Solid Thorium-Magnesium Eutetic

Description: Electrical resistivity properties of polycrystalline 39 wt % thorium-- magnesium eutectic are reported for the solid from room temperature to its melting point at 589 deg C and as a liquid from its melting point to 900 deg C. The electrical resistivity of the eutectic at the melting point was 69.5 microhm- centimeters; it decreased to a value of 64.8 microhm-centimeters at 900 C. Tantalum tubing was used to contain the alloy in the molten state. (auth)
Date: May 1, 1962
Creator: Provow, D. M. & Fisher, R. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cadmium sulfide/copper sulfide heterojunction cell research. Final report, February 26, 1979-July 15, 1980

Description: Extensive modifications were made to the multi-source deposition apparatus. These include the installation of a larger vacuum chamber on the existing system. The new chamber provides improved inter-source shielding, an improved substrate mounting and heating system, and a vacuum interlock for introducing substrates. CdS resistivity control by both In doping and off-stoichiometric deposition has been investigated. Indium doping has been achieved both by diffusion from a pre-deposited In layer an… more
Date: June 30, 1980
Creator: Thornton, J. A. & Cornog, D. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear magnetic resonance study of metallic scandium chlorides

Description: The /sup 45/Sc nuclear magnetic resonance was studied in samples having the general composition CsSc/sub x/Cl/sub 3/ (0.67 less than or equal to x less than or equal to 1.0) in the CsCl-ScCl/sub 3/-Sc system. In particular the structure of CsScCl/sub 3/ suggests that it may be a one-dimensional conductor, and an attempt was therefore made to detect the occurrence of a metal-insulator transition of the type characteristic of one-dimensional conductors. Conventional crossed-coil (nuclear inductio… more
Date: April 1, 1978
Creator: McMullen, T.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research, development and demonstration of nickel-iron batteries for electric vehicle propulsion. Annual report for 1979

Description: Research progress in the development of Ni/Fe batteries (electrodes in particular) for the period is described. The negative plate demonstrated a reliable lifetime of almost 1000 cycles; 20 mm positive plates were proved feasible; prototype cells yielded output at about 50 Wh/kg and 100 Wh/liter; program goals of 20% greater than these figures appear feasible. 27 figures, 20 tables. (RWR)
Date: June 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Applications of mesoscopic physics

Description: This report discusses the following topics: Acoustical nondestructive evaluation of heterogeneous materials in the multiple scattering regime. Classical and quantum superdiffusion in a time-dependent random potential. Negative Magnetoresistance in Variable Range Hopping Conduction. Reproducible Conductance Fluctuations in Macroscopic Anderson Insulators. Feasibility of far-infared lasers using multiple semiconductor quantum wells.
Date: January 1, 1992
Creator: Feng, Shechao.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Parametric study of the stability margins of cable-in-conduit superconductors: experiment

Description: In a previous experiment on the stability of cable-in-conduit superconductors, we sometimes observed multivalued stability margins, which we attributed to strong heating-induced transient flows. We proposed a schematic theory from which we derived a scaling relation for the limiting current below which the stability margin is always singlevalued. Measurements at different magnetic fields are used to test the scaling with critical temperature and resistivity. We also examine the scaling with hea… more
Date: January 1, 1980
Creator: Lue, J. W. & Miller, J. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3

Description: A method is described for obtaining monodomain PbTiO{sub 3} single crystals with high electrical resistivity (10{sup 10}{Omega} cm) and low dielectric frequency dispersion. The single crystals of PbTiO{sub 3} were grown by flux solution method. Space charge related defects, which result in the large dielectric frequency dispersion, were eliminated by heat treatments. 90{degrees} domains were removed by applying a unidirectional compressive stress along the <100> crystallographic direction. The … more
Date: May 1, 1992
Creator: Li, Z.; Xu, X. Z.; Dai, X. H.; Lam, D. J. & Chan, S. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radially resolved measurements of ''q'' on the ATC tokamak

Description: This paper describes a new technique for directly measuring the safety factor, or q, profile in a tokamak. A tightly collimated neutral beam capable of injecting approximately 100 mA of 30 keV deuterium atoms was mounted on the ATC tokamak. By proper tangential aiming of the beam a strong concentration of circulating fast ions was created at a chosen plasma minor radius. By examining the orbits of these ions with a multi-sight-line charge exchange detector, it was possible to measure the shifts… more
Date: April 1, 1978
Creator: Goldston, R.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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TRANSIENT RADIATION EFFECTS IN CAPACITORS AND DIELECTRIC MATERIALS

Description: Measurements of dielectric leakage, capacitance, electric strength, andd charge scattering phenomena were performed at the Kukla and Godiva III critical assemblies for tantalum and aluminum electrolytic, wax- and oilimpregnated paper, mylar, mica, and ceramic capacitors, and for mylar and Vitamin B-impregnated paper. Leakage data indicate that gamma induced conductivity in capacitor dielectric varies directly with gamma DELTA , where gamma is the gamma radiation rate and DELTA is 0.9 for mylar,… more
Date: August 15, 1961
Creator: Wicklein, H. W. & Dickhaut, R. H.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
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Neutron diffraction study of magnetic order in the ternary superconductor ErMo/sub 6/Se/sub 8/

Description: Synthesis of new classes of ternary superconducting materials has led to compounds which also show a strong tendency toward magnetic order when one of the constituent elements is a rare earth. Powder neutron diffraction data on superconducting (T/sub s/ approximately 6 K) samples of ErMo/sub 6/Se/sub 8/ taken in the temperature range 0.05 to 2.0 K show that magnetic Bragg peaks develop at T/sub M/ = 1.1 K, in agreement with specific heat studies. However, it is not possible to index these new r… more
Date: 1977~
Creator: Lynn, J. W.; Moncton, D. E.; Shirane, G.; Thomlinson, W.; Eckert, J. & Shelton, R. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetotelluric/audiomagnetotelluric study of the Zuni Hot Dry Rock Geothermal Prospect, New Mexico

Description: The Los Alamos Scientific Laboratory has been investigating a large area in New Mexico for Hot Dry Rock geothermal potential. The area includes parts of the Jemez volcanic lineament and the central Rio Grande rift. LASL has completed a detailed magnetotelluric/audiomagnetotelluric survey covering 161 square km over an area of high heat flow, south of Zuni, NM. The data collection was collected and preliminary analysis phases of a regional MT survey which suggest the Jemez lineament is associate… more
Date: January 1, 1980
Creator: Ander, M.E.; Goss, R.; Strangway, D.; Hillebrand, C.; Laughlin, A.W. & Hudson, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal and electrical conductivities of high purity tantalum

Description: The electrical resistivity and thermal conductivity of three high purity tantalum samples have been measured as functions of temperature over a temperature range of 5K to 65K. Sample purities ranged up to a resistivity ratio of 1714. The highest purity sample had a residual resistivity of .76 x 10/sup -10/OMEGA-m. The intrinsic resistivity varied as T/sup 3/./sup 9/ from 10K to 31K. The thermal conductivity of the purest sample had a maximum of 840 W/mK at 9.8K. The intrinsic thermal resistivit… more
Date: January 1, 1978
Creator: Archer, S. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Titanium/gold process characterization

Description: Characterization of the titanium/gold (Ti/Au) deposition process used at the Allied-Signal Inc., Albuquerque Microelectronics Operation (AMO) was performed. Tests were conducted to set up evaporation parameters, correlate titanium and gold thicknesses to sheet resistance, improve thickness uniformity, and reduce frontside contamination of deposit material on product wafers. The Ti/Au process is the final step in the production of integrated circuits (ICs) at the AMO wafer fabrication facility. … more
Date: November 1, 1991
Creator: Fajardo, L.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Determination of optimum electrolyte composition for molten carbonate fuel cells

Description: The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overa… more
Date: January 1, 1987
Creator: Yuh, C. Y. & Pigeaud, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Superconductivity: Past, present, and future

Description: This paper provides an overview of superconductor research and development activities, with emphasis on the potential of high-{Tc} materials for future applications. Superconductor applications are grouped under the following categories: electronics/instrumentation, bulk material/castings, research devices, industrial/commercial, electric power, and transportation/propulsion. Near-term applications are typically based on thin film and cast forms of high-{Tc} materials, while large-scale applica… more
Date: January 1, 1992
Creator: Uherka, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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MHD compressor---expander conversion system integrated with GCR inside a deployable reflector

Description: This work originates from the proposal MHD Compressor-Expander Conversion System Integrated with a GCR Inside a Deployable Reflector''. The proposal concerned an innovative concept of nuclear, closed-cycle MHD converter for power generation on space-based systems in the multi-megawatt range. The basic element of this converter is the Power Conversion Unit (PCU) consisting of a gas core reactor directly coupled to an MHD expansion channel. Integrated with the PCU, a deployable reflector provides… more
Date: April 20, 1989
Creator: Tuninetti, G. (Ansaldo S.p.A., Genoa (Italy). Research Div.); Botta, E.; Criscuolo, C.; Riscossa, P. (Ansaldo S.p.A., Genoa (Italy). Nuclear Div.); Giammanco, F. (Pisa Univ. (Italy). Dipt. di Fisica) & Rosa-Clot, M. (Florence Univ. (Italy). Dipt. di Fisica)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geophysics: Building E5032 decommissioning, Aberdeen Proving Ground

Description: integration of data from surveys using three geophysical technologies has provided information used to define the locations of buried utilities, tanks, vaults, and debris near building E5032 at the Aberdeen Proving Ground. Ground penetrating radar (GPR) profiles indicate the presence of buried pipes, tanks, reinforcement rods (rebar), and remnants of railroad tracks. A magnetic map constructed from a detailed magnetic survey on the north side of the building outlines buried iron-rich objects th… more
Date: July 1, 1991
Creator: McGinnis, L.D. & Miller, S.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel duplex vapor-electrochemical method for silicon solar cells. Quarterly progress report No. 7, August 1, 1977--October 31, 1977

Description: Silicon obtained by the SiF/sub 4/-Na reaction was analyzed by spark source mass spectrometry (SSMS). A partial listing of the results is given below. The concentration units in parentheses are ppM wt. B(0.1), Al(0.8), Ga(0.06), P(0.2), F(0.1), Na(1.0), V(0.04), Mo(0.3), Ti(2.0), Zr(2.0), Mn(0.1), Ni(2.0), Zn(0.01), Cu(20.0), Cr(11.0), Fe(55.0). An excellent starting material for silicon solar cells is obtained on the basis of the low levels of B, Al, Ga, P and As. The source of the Fe and Cr i… more
Date: December 1, 1977
Creator: Kapur, V.K.; Nanis, L. & Sanjurjo, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Anomalous rf magnetoresistance in copper at 4/degree/K

Description: We have measured the effect of a magnetic field on the surface resistance of polycrystalline Cu at f = 1.2 GHz and at 4.4/degree/K; under these conditions the surface resistance is well into the anomalous skin effect regime but has not reached its limiting value. We find that the transverse and longitudinal magnetoresistance are an order of magnitude smaller than the DC magnetoresistance and depend quadratically on the field. At low fields we observe a decrease in surface resistance with increa… more
Date: March 1, 1988
Creator: Halama, H. J.; Prodell, A. G.; Rogers, J. T.; De Panfilis, S.; Melissinos, A. C.; Moskowitz, B. E. et al.
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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