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in subjects: "Copper Oxides"

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Chemical Technology Division Unit Operations Section Monthly Progress Report, September 1961

Nine samples of ThO/sub 2/ -UO/sub 2/ prepared as part of the solgel process development studies showed no consistent effects from small variations in several process parameters. The reaction of methane and copper oxide was studied. Engineering studies of the continuous dissolution of simulated U-Zr-Sn fuels in 6.5 M NH4F, 0.6-1.0 M NH/sub 4/NO/sub 3/, 0.1 M H/sub 2/O/sub 2/ were continued in modified 6-in.-dia. equipment. A total of 1642 kg of U from NaK bonded SRE Core I fuel rods wad dejacke… more

Date: April 1, 1962

Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Chemical Technology Division, Unit Operations Section Monthly Progress Report, June 1961

An interfacial viseometer was built for use in an interfacial phenomena study. Installation of a 6-in.-ID foam separation column system was completed. The dispersiondrying-sintering characteristics of six low-nitrate batches of thoria sol material were studied. The average effective porosity of the CuO pellets used for reactor helium purification was determined to be 0.0545 for H/ sub 2/ transport and 0.0526 for CO transport. In continuous Zirflex dissolution studies, no H/sub 2/O/sub 2/ decomp… more

Date: January 23, 1962

Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Copper and cobalt are the key elements in syngas conversion catalyst systems used for higher alcohol synthesis. Their proximity and synergy sensitively control the selectivity and efficiency of the process. It is believed that their outer electronic charge distribution which is responsible for their electrical and magnetic properties might be governing their catalytic properties also. To examine the correlation between catalytic and magnetic properties, a series of copper cobalt catalysts (Co/C… more

Date: January 14, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Chemical Technology Division, Unit Operations Section Monthly Progress Report, May 1961

The experimental results on the oxidation of H from a He stream with CuO pellets were very close to the predicted behavior based on the mathematical model. Experimental measurements of uranyl sulfate loading rates on chloride equilibrated resin showed little variation with solution concentrations. A tentative flowsbeet was proposed for cost analysis of processing a Pebble Bed Reactor. A U-Zr plate was dissolved in nitrate-free Zirflex solution. An authentic TRIGA prototype was processed in engi… more

Date: December 26, 1961

Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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ORGANIC ELECTROLYTE BATTERY. Final Report.

No Description Available.

Date: January 1, 1969

Creator: McDonald, G D

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Elastic constants and the structural phase transition in La sub 2-x Sr sub x CuO sub 4

Resonant ultrasound spectroscopy is used to measure the temperature dependence of all six elastic moduli of La{sub 2-x}Sr{sub x}CuO{sub 4}. A giant softening (> 50% reduction) in the in-plane shear modulus, c{sub 66}, is observed and is attributed to the tetragonal-orthorhombic structural phase transition in this material. This phase transition and the corresponding softening is examined with a simple anharmonic mechanical model and a macroscopic Ginsburg-Landau formalism exploiting the full sy… more

Date: January 1, 1991

Creator: Sarrao, J.L.; Lei, Ming; Stekel, A.; Bell, T.M.; Leisure, R. G.; Sham, L.J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Techniques and processes for the measurement of the resonances of small single crystals

The mechanical resonances of small oriented single crystals of materials of interest to basic science and engineering can be used to determine all the elastic moduli and the ultrasonic attenuation of these materials. To measure the resonances of the samples without introducing the resonances of the measuring system requires that the transducers be non-resonant at the frequencies of interest, and that they be well isolated from their mounts. However, for samples near 1 mm in the largest dimensio… more

Date: January 1, 1991

Creator: Migliori, A.; Stekel, A.; Sarrao, J.L.; Visscher, W.M.; Bell, T. & Lei, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Modeling of Integrated Environmental Control Systems for Coal-Fired Power Plants Quarterly Report: Final Report

The Integrated Environmental Control Model (IECM) was designed to permit the systematic evaluation of environmental control options for pulverized coal-fired (PC) power plants. Of special interest was the ability to compare the performance and cost of advanced pollution control systems to conventional'' technologies for the control of particulate, SO{sub 2} and NO{sub x}. Of importance also was the ability to consider pre-combustion, combustion and post-combustion control methods employed alone… more

Date: May 1, 1991

Creator: Rubin, E. S.; Salmento, J. S.; Frey, H. C.; Abu-Baker, A. & Berkenpas, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Theoretical modeling and experimental characterization of planar defects in Y sub 2 Ba sub 4 Cu sub 6+x O sub 14+x

Crystallographic defects and phase transformations in the system Y{sub 2}Ba{sub 4}Cu{sub 6 + x}O{sub 14 + x}(0{le}{times}{le}4) are investigated by high resolution transmission electron microscopy (TEM) and static lattice, three dimensional Monte Carlo computer simulations. High resolution images of partially transformed (x = 2 to x = 1) material reveal a prevalence of CuO planar defects (stacking faults) associated with the transformation and an absence of disturbance to the perovskite Ba-Y-Ba… more

Date: November 1, 1990

Creator: Burmester, C. P.; Fendorf, M.; Gronsky, R. & Wille, L. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The use of BaF sub 2 buffer layers for the sputter-deposition of TlCaBaCuO thin-film superconductors

Thin films of the Tl-based superconductors often have relatively poor properties because of film/substrate interdiffusion which occurs during the anneal. We have therefore investigated the use of BaF{sub 2} as a diffusion barrier. TlCaBaCuO thin films were deposited by dc magnetron sputtering onto MgO <100> substrates, both with and without an evaporation-deposited BaF{sub 2} buffer layer, and post-annealed in a Tl over-pressure. Electrical properties of the films were determined by four-point … more

Date: January 1, 1989

Creator: Hubbard, K. M.; Arendt, P. N.; Brown, D. R.; Cooke, D. W.; Elliott, N. E.; Farr, J. D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Laser deposition and laser modification of high-temperature superconducting thin films

Applications of high-temperature superconductors (HTSC) may require epitaxial films with {Tc}{ge}77 K, and J{sub c}{ge}10{sup 6} A/cm{sup 2}. In situ pulsed laser deposition (PLD) is suitable for fabrication of such films. We report parametric studies on the effect of laser and processing parameters on the crystallinity, epitaxy and electrical properties of laser-deposited HTSC thin films. In addition, several laser-based processes were used to modify the electrical properties ({Tc} and J{sub c… more

Date: January 1, 1991

Creator: Dye, R. C.; Foltyn, S. R.; Nogar, N. S.; Wu, X. D.; Peterson, E. J. & Muenchausen, R. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Spectral weight changes at the superconducting transition of Bi sub 2 Sr sub 2 CaCu sub 2 O sub 8+. delta

An overview of our gap studies in high-{Tc} superconductors is presented for the workshop on Fermiology of high-{Tc}'s. The work is centered on the study of single crystal Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}. In a conventional BCS superconductor, a superconducting gap {Delta} is formed when the near Fermi edge electrons condense to form Cooper pairs at low temperatures. As the material goes superconducting the density of states is modified such that the spectral intensity in the regio… more

Date: January 1, 1991

Creator: Dessau, D. S.; Shen, Z. X.; Wells, B. O.; Spicer, W. E. (Stanford Univ., CA (United States). Stanford Electronics Labs.) & Arko, A. J. (Los Alamos National Lab., NM (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Static and dynamic spin fluctuations in the spin glass doping regime in La sub 2-x Sr sub x CuO sub 4+y

We review the results of neutron scattering studies of the static and dynamic spin fluctuations crystals of La{sub 2-x}Sr{sub x}CuO{sub 4+{delta}} in the doping regime intermediate between the Neel and superconducting regions. In this regime the in-plane resistance is linear in temperature down to {approximately}80 K with a crossover due to logarithmic conductance effects at lower temperatures. The static spin correlations are well-described by a simple model in which the inverse correlation le… more

Date: January 1, 1991

Creator: Birgeneau, R.J.; Belk, N.; Kastner, M.A.; Keimer, B. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics); Endoh, Y. (Tohoku Univ., Sendai (Japan). Dept. of Physics); Erwin, R.W. (National Inst. of Standards and Technology, Gaithersburg, MD (United States)) et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The influence of anharmonic phonons on the isotope effect in high- Tc oxides

Anharmonic phonons are examined to study the unusual isotope effect exponents for the high-{Tc} oxides. Within a simple model of anharmonicity, the mass dependences of the electron-phonon coupling constant {lambda} and the phonon frequency determine the isotope effect exponent {alpha} as a function of coupling strength. A model in which the outer wells of a multiple-well potential deepen as the orthorhombic/low temperature tetragonal phase transition in La{sub 2-x}M{sub x}CuO{sub 4} is approach… more

Date: January 1, 1992

Creator: Crespi, V.H. & Cohen, M.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent advances in high-temperature superconductor wire fabrication and applications development

In this paper, recent advances in fabrication of HTS wires are summarized, and detailed discussion is provided for developments in near- and intermediate-term applications. Near-term applications, using presently obtainable current densities, include: liquid-nitrogen depth sensors, cryostat current leads, and magnetic bearings. Intermediate-term applications, using current densities expected to be available in the near future include fault-current limiters and short transmission lines. 25 refs.

Date: January 1, 1992

Creator: Hull, J.R. & Uherka, K.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Quarterly Status Report on Ultra High Temperature Reactor Experiment (UHTREX) for Period Ending November 20, 1961

The detailed design of the reactor proper was essentially completed and preparations were made for procurement of the carbon components and the pressure vessel. Design of the UHTREX facility has progressed to Titie lI. Design information is included on copper oxide beds and molecular sieves for gas cleanup. In other work, irradiation of capsules containing UHTREX fuel elements is reported along with fuel recycle research. (J.R.D.) 9578(Faye unscannable abstract)

Date: December 1, 1961

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of high temperature superconductors for magnetic field applications

The key requirement for magnetic field applications of high temperature superconductor (HTS) materials is to have conductors with high transport critical current density available for magnet builders. After 3 or 4 years of being without any such object, conductor makers have had recent success in producing simple conductor prototypes. These have permitted the construction of simple HTS magnets having self fields exceeding 1 tesla at 4K. Thus the scientific feasibility of making powerful HTS mag… more

Date: January 1, 1991

Creator: Larbalestier, D.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Chemical Technology Division Unit Operations Section Monthly Progress Report, April 1962

Bubble size measurements in the foam column showed that a spinnerette with 50 mu holes gave a nearly normal distribution of bubbles sizes while a coarse fritted glass gas sparger had a tail of large bubbles which did not fit the normal curve. A set of equations solvable by a finite difference technique are presented which completely describe the irreversible reaction rate of H/sub 2/ or CO with a fixed bed of CuO pellets. Radiation damage tests are in progress to evaluate plastics for the Trans… more

Date: October 1, 1962

Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Electron irradiation effects in YBa/sub 2/Cu/sub 3/O/sub 7-delta/ single crystals

Defect structures in YBa/sub 2/Cu/sub 3/O/sub 7/minus/delta/ produced by electron irradiation at 300/degree/K, were investigated by transmission electron microscopy. Threshold energies for the production of visible defects were determined to b 152 keV and 131 keV (+- 7 keV) in directions near the a- and b-axes, respectively (b > a, both perpendicular to c, the long axis in the orthorhombic structure). During above-threshold irradiations in an electron flux of 3 x 10 /sup 18/ cm/sup /minus/2/s/s… more

Date: April 1, 1988

Creator: Kirk, M.A.; Baker, M.C.; Liu, J.Z.; Lam, D.J. & Weber, H.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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LABORATORY INVESTIGATIONS IN SUPPORT OF FLUID-BED FLUORIDE VOLATILITY PROCESSES. PART XX. FISSION-PRODUCT TELLURIUM OFF-GAS DISPOSAL IN THE FLUID-BED FLUORIDE VOLATILITY PROCESS.

No Description Available.

Date: January 1, 1968

Creator: Vissers, D.R. & Steindler, M.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Preparation of oxide superconductors

Preparation of bulk superconductors by cold pressing and sintering of metal oxides has been optimized in this study. A knowledge of phase behavior was used in developing a flux method for growing superconducting single crystals of yttrium and gadolinium based superconductors. Means of achieving single-phase, high-density samples of (Rare Earth)-Ba/sub 2/Cu/sub 3/O/sub 7/ with optimal electronic properties are reviewed. 2 refs., 2 figs.

Date: January 1, 1988

Creator: Peterson, D.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Chemical Technology Division, Unit Operations Section Monthly Progress Report, August 1961

Engineering studies of a 6-in.-ID countercurrent foam column were started. The capacity of Mark II Stacked Clone Contactor was found to be limited by gradually increasing entrainment. Thoria sols were prepared from trough denitrator products in a conical bottom tank agitated by circulation through an external centrifugal pump. Experimental results agreed favorably with predicted results for the reaction of CO with CuO and fur the simultaneous reactions of H/ sub 2/ and CO with CuO. In a 2-in. d… more

Date: March 1, 1962

Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Energetics and statistics of order in alloys with application to oxide superconductors

Now that first-principles calculations of ordering transformations are becoming increasingly accurate, the deficiencies of earlier mean field methods are becoming increasingly apparent. New techniques, based on cluster expansions, are now alleviating many of the earlier problems and are producing very satisfactory results. These ideas will be illustrated for the case of oxygen ordering in the YBa{sub 2}Cu{sub 3}O{sub z} superconducting compound, for which a very simple two-dimensional Ising mod… more

Date: June 1, 1991

Creator: de Fontaine, D. (Lawrence Livermore National Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering); Ceder, G. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science and Engineering) & Asta, M. (Lawrence Livermore National Lab., CA (United States) California Univ., Berkeley, CA (United States).

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Sintering of Bulk High - Tc Superconductors: Bi-Sr-Ca-Cu-O

Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (2212) and (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} (2223) superconductors have orthorhombic crystal structures. They form platelike grains that at high temperatures grow primarily in the a-b planes and not in the c direction. The diffusional properties of Bi-Sr-Ca-Cu-O superconductors are so anisotropic that 2212 and 2223 cannot, in general, be densified by solid-state sintering. Improved densification can be achieved by application of pressure or… more

Date: May 1, 1992

Creator: Goretta, K. C.; Lanagan, M. T.; Kaufman, D. Y.; Biondo, A. C.; Wu, C. T.; Loomans, M. E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department