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

Description: 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: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determination of properties of fluids for solar-cooling applications. Literature survey

Description: A detailed literature search of the available thermodynamic data of proposed refrigerant/absorbent pairs and measurement of those data that are unmeasured or unreliable are reported. The data to be obtained for the pure fluids included: the critical temperature, pressure and volume; the vapor pressure curve; the latent heat of vaporization at the normal boiling point; the freezing point; the specific heat of the liquid and vapor; and the specific volumes of the saturated liquids and vapors. For… more
Date: February 1, 1981
Creator: Podoll, R.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hot pressing of EuB/sub 6/

Description: Europium boride pellets with 92% of theoretical density were prepared by hot-pressing. By ball milling the starting powder, hot-pressing temperature could be reduced to 1700/sup 0/C. The lower hot-pressing temperature provided better control over final density and gave a more desirable microstructure.
Date: February 1, 1979
Creator: Hollenberg, G. W. & Beutler, P. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Far-infrared studies of superconducting V/sub 3/Si, Nb/sub 3/Ge, and Nb

Description: Optical techniques in the far infrared region (10 to 200 cm/sup -1/) are to explore the basic superconducting behavior of the high temperature superconductors V/sub 3/Si, Nb/sub 3/Ge, Nb, and granular NbN. Such spectroscopy yields accurate gap values, information about the temperature dependence of superconducting properties, values of the electron-phonon spectral function, and insight into grain-to-grain coupling in inhomogeneous geometries. These results are used to calculate basic supercondu… more
Date: February 23, 1981
Creator: Perkowitz, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Short coherence length superconductors: Intermediate regime between BCS and bosons

Description: In order to understand the high {Tc} materials, conventional superconductors and their metallic normal states are examined to see how generalizations of BCS pairing may lead to unconventional properties. The persistence of gap-like features in the normal state up to temperatures several times {Tc} is pointed out. The short coherence length and normal state pseudo-gaps are suggestive of preformed pairs which Bose condense at the superconducting transitions; the normal state is a degenerate Fermi… more
Date: February 1, 1994
Creator: Engelbrecht, J. R.; Randeria, M. & Sa de Melo, C. A. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microstructure and Corrosion Behavior of the Cu-Pd-X Ternary Alloys for Hydrogen Separation Membranes

Description: CuPd alloys are among the most promising candidate materials for hydrogen separation membranes and membrane reactor applications due to their high hydrogen permeability and better sulfur resistance. In order to reduce the Pd content and, therefore, the cost of the membrane materials, efforts have been initiated to develop CuPdM ternary alloys having a bcc structure. The advantages of having Pd as a hydrogen separation membrane are: (1) high hydrogen selectivity; and (2) high hydrogen permeabili… more
Date: February 26, 2012
Creator: Dogan, O. N.; Gao, M. C. & Howard, B. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal expansion of gadolinium in the vicinity of the Curie point. [270 to 320/sup 0/K, Curie point exponents]

Description: The c- and a-axis linear thermal expansivities of high purity single crystals of gadolinium were measured in the temperature range 270/sup 0/K to 320/sup 0/K. Length changes were translated to capacitance changes with a modified normal geometry 3-terminal capacitance dilatometer. An ac 3-terminal capacitance bridge was employed to measure nominal 10 pF capacitances to a precision of 10/sup -7/ pF, which corresponds to a relative length change sensitivity of 10/sup -10/. A 25 ohm platinum resist… more
Date: February 1, 1977
Creator: Dolejsi, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Filamentary niobium--tin superconductors fabricated by a powder metallurgy approach

Description: Procedures are described for making superconducting tapes and wires containing filments of the A-15 compound, Nb/sub 3/Sn, by powder metallurgy techniques. The Nb/sub 3/Sn filaments, typically 1-5 m thick, are formed by a short heat treatment. The effects of process variables on the microstructure of the tapes and wires were investigated. Microstructural aspects were examined by optical metallography and transmission electron microscopy. A pulsed field technique was used to determine the critic… more
Date: February 1, 1976
Creator: Hemachalam, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Determination of the phase diagram of the electron doped superconductor Ba(Fe1-xCox)2As2

Description: Systematic measurements of the resistivity, heat capacity, susceptibility and Hall coefficient are presented for single crystal samples of the electron-doped superconductor Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2}. These data delineate an x-T phase diagram in which the single magnetic/structural phase transition that is observed for undoped BaFe{sub 2}As{sub 2} at 134 K apparently splits into two distinct phase transitions, both of which are rapidly suppressed with increasing Co concentration. … more
Date: February 15, 2010
Creator: Chu, Jiun-Haw; Analytis, James G.; Kucharczyk, Chris; Fisher, Ian R. & /Stanford U., Geballe Lab.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Progress in Lattice Qcd at Finite Temperature.

Description: I review recent developments in lattice QCD at finite temperature, including the determination of the transition temperature T{sub c}, equation of state and different static screening lengths. The lattice data suggest that at temperatures above 1.5T{sub c} the quark gluon plasma can be considered as gas consisting of quarks and gluons.
Date: February 11, 2007
Creator: Petreczky, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solvent Refined Coal (SRC) process. Quarterly technical progress report, January 1979-March 1979

Description: This report summarizes the progress of the Solvent Refined Coal (SRC) Project by the Pittsburg and Midway Coal Mining Co. for the Department of Energy for the period January 1, 1979 to March 31, 1979. Activities included the operation and modification of the Solvent Refined Coal Pilot Plant at Fort Lewis, Washington; the Process Development Unit P-99 at Harmarville, Pennsylvania; and research at Merriam Laboratory in Merriam, Kansas. The Pilot Plant processed Powhatan No. 5 Coal in the SRC-II m… more
Date: February 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development and evaluation of supercritical fluid chromatography/mass spectrometry for polar and high-molecular-weight coal components: Technical progress report for the period October 1, 1985 - September 30, 1986

Description: Technical progress toward the programmatic goals of developing and evaluating SFC/MS for the analysis of higher-molecular-weight compounds was made in the following areas: Studies have been conducted to characterize the requirements for and to facilitate the transfer of thermal energy to the capillary flow restrictor region. Such studies have resulted in a new interface probe design which allows better transport of higher molecular weight, less volatile compounds decreasing the mass discriminat… more
Date: February 1, 1987
Creator: Chess, E. K.; Kalinoski, H. T.; Wright, B. W. & Smith, R. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Process feasibility study in support of silicon material Task I. Final report, October 1, 1975-February 6, 1981

Description: The Low-Cost Solar Array (LSA) Project is directed toward effective cost reduction in the production of silicon for solar cells. Results are presented for process system properties, chemical engineering and economic analyses of the new technologies and processes being developed for the production of lower cost silicon for solar cells. Major physical, thermodynamic and transport property data are reported for the following silicon source and processing chemical materials: silane, silicon tetrach… more
Date: February 6, 1981
Creator: Yaws, C. L.; Li, K. Y.; Hopper, J. R.; Fang, C. S. & Hansen, K. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

LATTICE QCD AT FINITE TEMPERATURE AND DENSITY.

Description: With the operation of the RHIC heavy ion program, the theoretical understanding of QCD at finite temperature and density has become increasingly important. Though QCD at finite temperature has been extensively studied using lattice Monte-Carlo simulations over the past twenty years, most physical questions relevant for RHIC (and future) heavy ion experiments remain open. In lattice QCD at finite temperature and density there have been at least two major advances in recent years. First, for the … more
Date: February 24, 2004
Creator: Blum, T.; Creutz, M. & Petreczky, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DYNAMIC MECHANICAL ANALYSIS CHARACTERIZATION OF GLOVEBOX GLOVES

Description: As part of the characterization of various glovebox glove material from four vendors, the permeability of gas through each type as a function of temperature was determined and a discontinuity in the permeability with temperature was revealed. A series of tests to determine the viscoelastic properties of the glove materials as a function of temperature using Dynamic Mechanical Analysis (DMA) was initiated. The glass transition temperature and the elastic and viscoelastic properties as a function… more
Date: February 29, 2012
Creator: Korinko, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High-T/sub c/ superconductor and its use in superconducting magnets

Description: Many of the proposed uses for the high-T/sub c/ superconductor involve the creation of a magnetic field using superconducting coils. This report will assess what is known about the high-T/sub c/ superconductors and take a realistic look at their potential use in various kinds of superconducting magnets. Based on what is known about the high-T/sub c/ superconductors, one can make a ''wish list'' of things that will make such materials useful for magnets. Then, the following question is asked. If… more
Date: February 1, 1988
Creator: Green, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Genotoxicity of complex mixtures: CHO cell mutagenicity assay

Description: A Chinese hamster ovary (CHO) mammalian cell assay was used to evaluate the genotoxicity of complex mixtures (synthetic fuels). The genotoxicity (mutagenic potency) of the mixtures increased as the temperature of their boiling range increased. Most of the genotoxicity in the 750/sup 0/F+ boiling-range materials was associated with the neutral polycyclic aromatic hydrocarbon (PAH) fractions. Chemical analysis data indicate that the PAH fractions of high-boiling coal liquids contain a number of k… more
Date: February 1, 1985
Creator: Frazier, M. E. & Samuel, J. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(6)Li, (7)Li Nuclear Magnetic Resonance Investigation of Lithium Coordination in Binary Phosphate Glasses

Description: {sup 6}Li and {sup 7}Li solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy has been used to investigate the local coordination environment of lithium in a series of xLi{sub 2}O {center_dot} (1-x)P{sub 2}O{sub 5} glasses, where 0.05 {le} x {le} 0.55. Both the {sup 6}Li and {sup 7}Li show chemical shift variations with changes in the Li{sub 2}O concentration, but the observed {sup 6}Li NMR chemical shifts closely approximate the true isotropic chemical shift and … more
Date: February 8, 1999
Creator: Alam, T.M.; Boyle, T.J.; Brow, R.K. & Conzone, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Paramagnetism and reentrant behavior in quasi-one-dimensional superconductors at high magnetic fields

Description: The thermodynamics of quasi-one-dimensional superconductors in the presence of large magnetic fields is studied. When the quantum effects of the magnetic field are taken into account, several reentrant superconducting phases persist at very high fields. In the last reentrant phase the free energy change, the specific heat jump and the excess magnetization are estimated near the critical temperature. In particular, the excess magnetization is found to be paramagnetic as opposed to diamagnetic in… more
Date: February 1996
Creator: Sa de Melo, C. A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Direct evidence for, and the nature of, Josephson coupling between Cu-O bilayers in a highly-anisotropic superconductor

Description: The angular-dependent, c-axis resistivity for oxygen-deficient YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} single crystals is shown to be a maximum for fields parallel to the c-axis, i.e., for zero macroscopic Lorentz force, and agrees with a series stack of Josephson tunnel junctions. The c-axis component of field dominates the c-axis dissipation in most cases. The results indicate the possibility of an unusual normal-state c-axis conductance and that the c-axis junctions may be extremely underd… more
Date: February 1, 1997
Creator: Hettinger, J. D.; Veal, B. W., Jr.; Paulikas, A. P.; Kostic, P.; Gray, K. E.; Washburn, B. R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Single crystal neutron diffraction study of the magnetic structure of TmNi{sub 2}B{sub 2}C

Description: Neutron diffraction techniques have been used to study the magnetic structure of single crystals of the magnetic superconductor (T{sub c} {congruent} 11K) TmNi{sub 2}B{sub 2}C. We find that below approximately 1.5K the magnetic moments order in an incommensurate spin wave with propagation vector q{sub m} = q{sub m} (a* +b*) (or q{sub m} = q{sub m} (a* + b*)) with q{sub m} = 0.094 {+-} 0.001. The spin wave is transverse with the moments aligned along the c-axis, and the observation of relatively… more
Date: February 1, 1997
Creator: Sternlieb, B.; Shapiro, S.; Stassis, C.; Goldman, A. I. & Canfield, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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