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in subjects: "Electric Conductivity"

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Correlation of alluvial deposits at the Nevada Test Site

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: Report

Partner: UNT Libraries Government Documents Department

open access

Cadmium sulfide/copper sulfide heterojunction cell research. Final report, February 26, 1979-July 15, 1980

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: 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

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: Report

Partner: UNT Libraries Government Documents Department

open access

Applications of mesoscopic physics

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: Report

Partner: UNT Libraries Government Documents Department

open access

Parametric study of the stability margins of cable-in-conduit superconductors: experiment

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: Article

Partner: UNT Libraries Government Documents Department

open access

Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3

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: Article

Partner: UNT Libraries Government Documents Department

open access

Radially resolved measurements of ''q'' on the ATC tokamak

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: Report

Partner: UNT Libraries Government Documents Department

open access

TRANSIENT RADIATION EFFECTS IN CAPACITORS AND DIELECTRIC MATERIALS

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: Book

Partner: UNT Libraries Government Documents Department

open access

Neutron diffraction study of magnetic order in the ternary superconductor ErMo/sub 6/Se/sub 8/

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: Article

Partner: UNT Libraries Government Documents Department

open access

Magnetotelluric/audiomagnetotelluric study of the Zuni Hot Dry Rock Geothermal Prospect, New Mexico

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: Article

Partner: UNT Libraries Government Documents Department

open access

Titanium/gold process characterization

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: Report

Partner: UNT Libraries Government Documents Department

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Determination of optimum electrolyte composition for molten carbonate fuel cells

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: Report

Partner: UNT Libraries Government Documents Department

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Superconductivity: Past, present, and future

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: Article

Partner: UNT Libraries Government Documents Department

open access

MHD compressor---expander conversion system integrated with GCR inside a deployable reflector

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: Report

Partner: UNT Libraries Government Documents Department

open access

Geophysics: Building E5032 decommissioning, Aberdeen Proving Ground

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: 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

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: Report

Partner: UNT Libraries Government Documents Department

open access

Anomalous rf magnetoresistance in copper at 4/degree/K

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: Report

Partner: UNT Libraries Government Documents Department

open access

Development of improved cathodes for solid oxide fuel cells

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: Report

Partner: UNT Libraries Government Documents Department

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Electrical Conductivity Measurements in Shock Compressed Liquid Nitrogen

The electrical conductivity of shock compressed liquid nitrogen was measured in the pressure range 20 to 50 GPa using a two-stage light-gas gun. The conductivities covered a range 4 x 10/sup -2/ to 1 x 10/sup 2/ ohm/sup -1/ cm/sup -1/. The data are discussed in terms of a liquid semiconductor model below the onset of the dissociative phase transition at 30 GPa. 15 refs., 1 fig.

Date: June 1, 1985

Creator: Hamilton, D. C.; Mitchell, A. C. & Nellis, W. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comments on photoelectron spectroscopy of high- Tc 's

The photoemission discussion session during the Argonne conference on Fermiology of High-{Tc}'s provided a forum to air a number of unresolved issues in photoelectron spectroscopy. These are: (a) what is the exact energy dependence of the line width of the quasiparticle peaks: (b) are there any chemical potential shifts with hole doping; (c) why is a superconducting gap not observed in Y-123; and (d) different groups report different results in the band structure of Bi-2212. The first issue, wh… more

Date: January 1, 1991

Creator: Arko, A. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Incomplete relaxation and finite beta plasmas

The treatment of plasma relaxation presented in this paper is a natural generalization of the earlier treatment of Taylor and yields predictions of finite beta plasma confinement. The analysis yields predictions for global reversed-field pinch (RFP) parameters such as ..beta../sub theta/, F, and theta. In qualitative accordance with the experimental evidence that RFP discharges have a cool outer region of high resistivity, we present a plasma model which permits vanishing wall values of pressur… more

Date: January 1, 1980

Creator: Turner, L. & Christiansen, J.P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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An HVEM study of displacement cascade damage in Nb/sub 3/Sn at 13 K

TEM images of the martensite structure in Nb/sub 3/Sn were recorded at various temperatures between 12 and 30/degree/K. The transition to the superconducting state was observed by a slight deflection of the electron beam due to a perturbation of the magnetic field of the objective lens at the sample. The primary interest is in irradiation effects due to fast neutrons from a fusion reactor, and therefore ion irradiation conditions that are somewhat comparable to this were selected. These consist… more

Date: February 1, 1988

Creator: Kirk, M. A.; Baker, M. C.; Kestel, B. J.; Weber, H. W. & Kampwirth, R. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Photovoltaic module electrical termination design requirement study

Motorola Inc., in conjunction with ITT Cannon, has conducted a study to develop information to facilitate the selection of existing, commercial, electrical termination hardware for photovoltaic modules and arrays. This volume of the report contains the executive summary. Module and array design parameters were investigated and recommendations were developed for use in surveying, evaluating, and comparing electrical termination hardware. Electrical termination selection criteria factors were dev… more

Date: July 1, 1980

Creator: Mosna, F.J. Jr. & Donlinger, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Spectral functions from Quantum Monte Carlo

In his review, D. Scalapino identified two serious limitations on the application of Quantum Monte Carlo (QMC) methods to the models of interest in High {Tc} Superconductivity (HTS). One is the sign problem''. The other is the analytic continuation problem'', which is how to extract electron spectral functions from QMC calculations of the imaginary time Green's functions. Through-out this Symposium on HTS, the spectral functions have been the focus for the discussion of normal state properties … more

Date: January 1, 1989

Creator: Silver, R.N.

Item Type: Article

Partner: UNT Libraries Government Documents Department