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in subjects: "Uranium Alloys"

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Stress corrosion cracking of uranium--niobium alloys

The stress corrosion cracking behavior of U-2/sup 1///sub 4/, 4/sup 1///sub 2/, 6 and 8 wt % Nb alloys was evaluated in laboratory air and in aqueous Cl/sup -/ solutions. Thresholds for crack propagation were obtained in these environments. The data showed that Cl/sup -/ solutions are more deleterious than air environments. Tests were also conducted in pure gases to identify the species in the air responsible for cracking. These data showed the primary stress corrodent is water vapor for the mo… more

Date: March 1, 1978

Creator: Magnani, N.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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SCANNING ELECTRON MICROSCOPE FRACTOGRAPHY OF A URANIUM--7.5 WT. PERCENT NIOBIUM--2.5 WT. PERCENT ZIRCONIUM ALLOY.

No Description Available.

Date: January 1, 1969

Creator: Bennett, R.K. & Winslow, F.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Laboratory-Scale Demonstration of the Fused Salt Volatility Process

The feasibility of processing enriched irradiated zirconium--uranium alloy fuel by the fused salt-fluoride volatility procedure has been demonstrated in laboratory tests with fuel having a burnup of over 10%. Uranium recoveries were greater than 99% and decontamination factors for radioactive fission products were 10/sup 6/ to 10/sup 6/. The UF/sub 6/ product contained significant quantities of nonradioactive impurities; additional work in this area is needed. (auth)

Date: August 1, 1962

Creator: Cathers, G. I.; Jolley, R. L. & Moncrief, E. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Pour stream breakup of molten IFR (Integral Fast Reactor) metal fuel in sodium

Tests have been conducted in which the breakup behavior of kilogram quantities of molten uranium, uranium-zirconium alloy, and uranium-iron alloy pour streams in 600C sodium was studied. A sodium depth of less than 0.3 m was required for hydrodynamic breakup and freezing of 25-mm pour streams of uranium and uranium-zirconium alloy with up to 400C melt superheat. The breakup material was primarily in the form of filaments and sheets with a settled bed voidage on the order of 0.9. The uranium-iro… more

Date: January 1, 1988

Creator: Gabor, J. D.; Purviance, R. T.; Aeschlimann, R. W. & Spencer, B. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Some recent observations on the radiation behavior of uranium silicide dispersion fuel

Addition of B{sub 4}C burnable poison results in higher plate swelling in both U{sub 3}Si{sub 2} and U{sub 3}Si-Al dispersion fuel plates and also decreases the blister threshold temperature of these plates. Prolonged annealing of U{sub 3}Si{sub 2}-Al fuel plates produced no blister after 696 hours at 400{degrees}C. Blister formation started between 257 hours and 327 hours at 425{degrees}C and between 115 hours and 210 hours at 450{degrees}C. Operation with breached cladding resulted in pillowi… more

Date: January 1, 1988

Creator: Hofman, G.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Chemical Technology Division, Annual technical report, 1991

Highlights of the Chemical Technology (CMT) Division's activities during 1991 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion and coal-fired magnetohydrodynamics; (3) methods for treatment of hazardous and mixed hazardous/radioactive waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an uns… more

Date: March 1, 1992

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Neutron scattering studies of heavy Fermions. [CeAl/sub 3/, UBe/sub 13/, CeCu/sub 2/Si/sub 2/, CeCu/sub 6/, ThBe/sub 13/, UPt/sub 3/, U/sub 2/Zn/sub 17/]

Heavy Fermions are f electron materials characterized by a large linear term in the low temperature specific heat and a large magnetic susceptibility at low temperatures. This implies that there is a narrow peak in the f electron density of states at the Fermi energy. Typical examples are CeAl/sub 3/, UBe/sub 13/, CeCu/sub 2/Si/sub 2/, CeCu/sub 6/, U/sub 2/Zn/sub 17/ and UPt/sub 3/. Neutron scattering measurements can play an important role in understanding the magnetic interactions in these sy… more

Date: January 1, 1985

Creator: Shapiro, S.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Irradiation performance of metallic fuels

Argonne National Laboratory has been working for the past five years to develop and demonstrate the Integral Fast Reactor (IFR) concept. The concept involves a closed system for fast-reactor power generation and on-site fuel reprocessing, both designed specifically around the use of metallic fuel. The Experimental Breeder Reactor-II (EBR-II) has used metallic fuel for all of its 25-year life. In 1985, tests were begun to examine the irradiation performance of advanced-design metallic fuel syste… more

Date: January 1, 1989

Creator: Pahl, R. G.; Lahm, C. E.; Porter, D. L.; Batte, G. L.; Hofman, G. L. (Argonne National Lab., Idaho Falls, ID (USA) & Argonne National Lab., IL (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Pulsed reactivity measurements of large /sup 235/U--Al castings in H/sub 2/O

The safe storage and handling of large /sup 235/U-Al castings at the Savannah River Plant are assured by limiting the number of fuel pieces and their spacing such that the k/sub eff/ calculated by KENO-IV with Hansen-Roach cross sections does not exceed some conservative limit with complete, accidental water immersion. For economic reasons, the conservative limit on the calculated k/sub eff/ is generally chosen as high as possible consistent with an accurate knowledge of the margin of error in … more

Date: January 1, 1977

Creator: Pellarin, D.J. & Jarriel, J.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Itinerant f-electron behavior in Ce and U compounds

The experimentally observed Fermi surface properties in URh/sub 3/, UIr/sub 3/, UGe/sub 3/, CeSn/sub 3/, CeB/sub 6/, U/sub 3/As/sub 4/, U/sub 3/P/sub 4/, and CeSb are reviewed. For the compounds with no magnetic order, band structure models of the Fermi surface geometry are confirmed and f-ligand hybridization is found to be dominant. For CeB/sub 6/, U/sub 3/As/sub 4/, and U/sub 3/P/sub 4/ the experiments show that both local moments and f hybridization are important. In CeSb new data can be ex… more

Date: April 1, 1985

Creator: Crabtree, G.W.

Item Type: 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]

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: Report

Partner: UNT Libraries Government Documents Department

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Magnetic anisotropy in the U/sub x/Th/sub 1-x/Zn/sub 8. 5/ system

We have investigated the source of the anisotropic susceptibility of UZn/sub 8.5/ by preparing single crystals of U/sub x/Th/sub 1-x/Zn/sub 8.5/ for small x. Preliminary indications are that anisotropic exchange, rather than crystal field effects, are responsible for the anisotropy, but possible impurity contributions to the (anisotropic) susceptibility of the ThZn/sub 8.5/ do not permit a stronger statement. Further measurements for small x show that both the electronic specific heat and the s… more

Date: January 1, 1986

Creator: Willis, J. O.; Fisk, Z.; Aikin, R. M.; McElfresh, M. W.; Thompson, J. D.; Zirngiebl, E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Superconductivity of heavy-electron uranium compounds

This paper reviews the status of the understanding of superconductivity in uranium heavy-electron compounds. 7 figs., 1 tab., 27 refs. (DWL)

Date: 1988~

Creator: Fisk, Z.; Borges, H.; McElfresh, M.; Smith, J. L.; Thompson, J. D.; Ott, H. R. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Hydrides and Metal-Hydrogen Systems. Final Report

The work reported deals with the preparation and physical properties, especially thermal dissociation pressures, and densities of hydrides, hydrogen- metal systems, and mixtures of hydrides with other substances. Possible applicatlons as moderators, high-temperature neutron shields, and low-temperature shields are cited and design problems discussed. Most of the data on dissociation pressures cover ranges and compounds not hltherto explored because of experimental difficulties and the basic kno… more

Date: April 30, 1951

Creator: Gibb, T. R. P., Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Muon Spin Relaxation and Knight Shift in the Heavy-Fermion Superconductor UPt3

Positive muon spin relaxation experiments have been conducted on the heavy-fermion superconductor UPt/sub 3/ in both the normal and superconducting states for zero, transverse, and longitudinally applied magnetic fields. Below 6 K in zero applied field, the ..mu../sup +/ relaxation rate is approximately twice that expected from /sup 195/Pt nuclear dipolar relaxation alone. Transverse- and longitudinal-field measurements show that the observed relaxation rate depends on magnetic field and is qua… more

Date: January 1, 1986

Creator: Cooke, D. W.; Heffner, R. H.; Hutson, R. L.; Schillaci, M. E.; Smith, J. L.; Willis, J. O. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thermophysical properties of thorium and uranium systems for use in reactor safety analysis

The data compilation is intended to serve as a preliminary set of thermophysical property values for use in reactor safety analyses of the Th--/sup 233/U reactor concept. The properties covered include mp, bp, enthalpy, heats of vaporization and fusion, heat capacity, thermal conductivity, density, thermal expansion, emissivity, viscosity, etc. The systems covered are Th, Th/sub 0/./sub 9/U/sub 0/./sub 1/, U, ThO/sub 2/, Th/sub 0/./sub 9/U/sub 0/./sub 1/O/sub 2/, UO/sub 2/, U/sub 0/./sub 8/Pu/s… more

Date: June 1, 1977

Creator: Fink, J.K.; Chasanov, M.G. & Leibowitz, L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Energy-beam processing studies on Ta/U and Ir/Ta systems. [Laser-and electron-beam melting]

Films of Ta metal on uranium and of Ir metal on tantalum have been irradiated and melted by pulses from Q-switched Ruby and frequency-doubled Nd:YAG lasers to investigate the nature of the resulting mixtures in light of the very different binary-phase diagrams of the two systems. In addition, a two-phase Ir-Ta alloy has been surface-processed with CW CO/sub 2/-laser radiation and with an electron beam in order to study microstructure refinement and test the advantage of using alloys as opposed … more

Date: November 11, 1983

Creator: Kaufmann, E. N.; Peercy, P. S.; Jacobson, D. C.; Draper, C. W.; Huegel, F. J.; Echer, C. J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Irradiation behavior of the CNEA's experimental uranium silicide dispersion fuel plates

Since 1978 the CNEA ECBE project has been involved in the development of dispersion fuel plates with four types of fuel materials -- UAl{sub x}, U{sub 3}O{sub 8}, U{sub 3}Si, and U{sub 3}Si{sub 2} -- to be used in low enriched (LEU < 20% {sup 235}U) fuel elements for research reactors. Miniplates with these fuel materials were manufactured at CNEA and were irradiated in the ORR in three series of irradiations as part of the RERTR miniplate irradiation program. The first irradiation contained U{… more

Date: January 1, 1988

Creator: Hofman, G.L.; Marajofsky, A.; Kohut, C. (Argonne National Lab., IL (USA) & Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Potentiometric determination of percent porosity in nickel electroplates on uranium metal

A potentiometric procedure has been developed to determine the percent porosity of nickel electroplates on uranium metal. In this case, percent porosity is defined as the ratio of the exposed uranium surface to the nickel electroplate surface times 100. Basically, this procedure exploits the high chemical reactivity between uranium metal and chloride ions in aqueous solution. It involves the potentiometric measurement of the corrosion potentials of coupled uranium/nickel metal electrodes in 0.0… more

Date: January 1, 1982

Creator: Dietrich, W.C. & Johnson, E.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Status of high-density fuel plates fabrication

Progress has continued on the fabrication of fuel plates with fuel zone loadings approaching 9gU/cm{sup 3}. Using Hot Isostatic Pressing (HIPping) successful diffusion bonds have been made with 110 Al and 6061 Al alloys. These bonds demonstrated the most critical processing step for proof-of-concept hardware. Two types of prototype highly-loaded fuel plates have been fabricated. First, a fuel plate in which 0.030 in. (0.76 mm) uranium compound wires are bonded within an aluminum cladding and se… more

Date: September 1, 1989

Creator: Wiencek, T.C.; Domagala, R.F. & Thresh, H.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Band description of materials with localizing orbitals

Density functional theory is a form of many-body theory which maps the problem onto an equivalent single particle-like system by limiting to the ground state (or some limited ensemble). So it should be surprising that this ground state theory could have any relevance whatsoever to the excitation properties of a material - and yet it does when used carefully. However, the most interesting materials involve active orbitals which are at least partially localized in space and this has profound effe… more

Date: March 1, 1986

Creator: Koelling, D.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Analysis of the series of moderately heavy fermion materials: CeSn/sub 3/, USn/sub 3/, and NpSn/sub 3/

The materials CeSn/sub 3/, USn/sub 3/, and NpSn/sub 3/ are all moderately heavy Fermion compounds with electronic specific heat coefficients of 73, 169, and 242 mJ/mole K/sup 2/. CeSn/sub 3/ is known as a mixed valent system and NpSn/sub 3/ is a weak itinerant antiferromagnet. All three are strongly enhanced. Being in the relatively simple Au/sub 3/Cu structure, they form an excellent set of materials to study as representatives of strongly enhanced systems. One would like to ascertain what pro… more

Date: May 1, 1985

Creator: Norman, M.R. & Koelling, D.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Heavy fermion materials. [UBe/sub 13/]

The heavy-fermion ground state occurs in a few select metallic compounds as a result of interactions between f-electron and conduction-electron spins. A characteristically large electronic heat capacity at low temperature indicates that the effective electron mass of these materials is more than two orders of magnitude greater than that expected for a free-electron metal. This heavy-fermion ground state can become superconducting or antiferromagnetic, exhibiting very unusual properties. These m… more

Date: January 1, 1986

Creator: Smith, J.L. & Cooke, D.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent developments of the US RERTR program

The status of the US Reduced Enrichment Research and Test Reactor (RERTR) Program is reviewed. After a brief outline of the RERTR Program objectives, goals and past accomplishments, emphasis is placed on the developments which took place during 1983 and on current program plans and schedules. Most program activities have proceeded as planned and a combination of two silicide fuels (U/sub 3/Si/sub 2/-Al and U/sub 3/Si-Al) was found to hold excellent promise for achieving the long-term program go… more

Date: January 1, 1983

Creator: Travelli, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department