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High-temperature of thermodynamic properties of sodium

Description: The set of high-temperature thermodynamic properties for sodium in the two-phase and subcooled-liquid regions which was previously recommended, has been modified to incorporate recent experimental data. In particular, replacement of the previously estimated critical constants with experimentally-determined values has resulted in substantial differences in the region of the critical point. The following thermodynamic properties were determined: pressure, density, enthalpy, entropy, internal ener… more
Date: January 1, 1977
Creator: Padilla, A. Jr.
Partner: UNT Libraries Government Documents Department
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Thermal strains in titanium aluminide and nickel aluminide composites

Description: Neutron diffraction was used to measure residual thermal strains developed during postfabrication cooling in titanium aluminide and nickel aluminide intermetallic matrix composites. Silicon carbide /Ti 14Al-21Nb, tungsten and sapphire/NiAl, and sapphire and SiC-coated sapphire/NiAl{sub 25}Fe{sub 10} composites were investigated. The thermal expansion coefficient of the matrix is usually greater than that of the fibers. As such, during cooldown, compressive residual strains are generated in the … more
Date: January 1, 1992
Creator: Saigal, A. (Tufts Univ., Medford, MA (United States). Dept. of Mechanical Engineering) & Kupperman, D.S. (Argonne National Lab., IL (United States))
Partner: UNT Libraries Government Documents Department
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Phase Transformations in Alumina. Technical Report, May to December 1961

Description: e transformation studies showed that synthetic aluminas produced in the laboratory were not transformed to alpha alumina at 400 to 700' deg n the presence of nitric acid and water vapor. Amorphous aluminn produced in the pilot plant was transformed to alpha alumina. This indicated that the amorphous alumina produced in the pilot plant is structurally predisposed to form alpha alumina. Most additives did not appear to have any special effects. Lithium formed zeta alumina, LiAl/sub 5/O/sub 8/. Ph… more
Date: December 1, 1961
Creator: Eding, H J; Huggins, M L & Brown, A G
Partner: UNT Libraries Government Documents Department
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Freely expanding detonation products: Scaling of rate processes

Description: Using the Los Alamos reactive hydrodynamics code KIVA, calculations have been made to simulate the free expansion of cylinders of detonation products into a high vacuum. The emphasis of this paper is on the scaling of rate processes with cylinder size and initial conditions as a function of position in the expanding mass. The processes considered include diffusion, unimolecular decomposition, biomolecular radical reactions, and vibrational relaxation. The calculations also give time-dependent v… more
Date: January 1, 1988
Creator: Greiner, N. R.
Partner: UNT Libraries Government Documents Department
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MHD power generation research, development and engineering. Quarterly progress report, October-December 1979

Description: Progress is reported on the following tasks: characterization of coal for open-cycle MHD power generation systems; compressive creep and strength studies of MHD preheater materials; preparation of coals for utilization in direct coal-fired MHD generation; characterization of volatile matter in coal; MHD materials evaluation; operability of the Moderate Temperature Slag Flow Facility; slag-seed equilibria and separations related to the MHD system; thermionic emission of coal and electrode materi… more
Date: January 1, 1979
Partner: UNT Libraries Government Documents Department
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Phenolic resin syntactic foams

Description: Syntactic foams were prepared from blends of six phenolic resins and carbon microbubbles. The compressive strength of the phenolic resin foams is equivalent to the strength of foams made from a polyimide resin. Ammonia evolved during the cure diffuses rapidly and is not bound by the foam.
Date: June 1, 1980
Creator: McIlroy, H. M.
Partner: UNT Libraries Government Documents Department
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Failure of sheathed thermocouples due to thermal cycling

Description: Open circuit failures (up to 100%) in small-diameter thermocouples used in electrically heated nuclear fuel rod simulator prototypes during thermal cycling tests were investigated to determine the cause(s) of the failures. The experiments conducted to determine the relative effects of differential thermal expansion, wire size, grain size, and manufacturing technology are described. It was concluded that the large grain size and embrittlement which result from certain common manufacturing anneal… more
Date: March 1, 1982
Creator: Anderson, R.L. & Ludwig, R.L.
Partner: UNT Libraries Government Documents Department
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Survey of physical property data for several alloys. [Nitronic 33; copper C10400; copper C17510]

Description: This report summarizes an examination of physical property data available in the literature for six alloys of potential interest to the Toroidal Fusion Core Experiment in the Fusion Energy Program. The properties of thermal expansion, density, specific heat, electrical resistivity, and thermal conductivity were compiled for six alloys: Nitronic 33, a low-nickel, high manganese stainless steel; nickel-base Inconnel Alloys 625, 718, and X-750; and copper alloys C10400 and C17510. The temperatures… more
Date: August 1, 1985
Creator: Pawel, R. E. & Williams, R. K.
Partner: UNT Libraries Government Documents Department
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Analysis of fuel relocation for the NRC/PNL Halden assemblies IFA-431, IFA-432, and IFA-513

Description: The effects of the thermally-induced cracking and subsequent relocation of UO/sub 2/ fuel pellets on the thermal and mechanical behavior of light-water reactor fuel rods during irradiation are quantified in this report. Data from the Nuclear Regulatory Commission/Pacific Northwest Laboratory Halden experiments on instrumented fuel assemblies (IFA) IFA-431, IFA-432, and IFA-513 are analyzed. Beginning-of-life in-reactor measurements of fuel center temperatures, linear heat ratings, and cladding … more
Date: April 1, 1980
Creator: Williford, R. E.; Mohr, C. L.; Lanning, D. D.; Cunningham, M. E.; Rausch, W. N. & Bradley, E. R.
Partner: UNT Libraries Government Documents Department
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Magnetic fusion energy annual report, July 1975--September 1976

Description: Supporting research activities continued to provide the technical basis for future mirror-confinement experiments. The industrial development of a high-current, high-field, high-current-density Nb/sub 3/Sn conductor was the main goal of the superconducting magnet program. Beam direct conversion was being developed as a means of raising the efficiency of neutral-beam production, and plasma direct conversion was shown to work as predicted. Conceptual designs were completed for various types of po… more
Date: December 2, 1976
Creator: Harrison, M.A.; McGregor, C.K. & Gottlieb, L. (eds.)
Partner: UNT Libraries Government Documents Department
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Instrument evaluation, calibration, and installation for the heater experiments at Stripa

Description: Borehole instrumentation for the measurement of temperature, displacement, and stress was evaluated, modified, calibrated, and installed in an underground site at Stripa, Sweden where experiments are currently underway to investigate the suitability of granite as a storage medium for nuclear waste. Three arrays of borehole instrumentation measure the thermomechanical effects caused by electrical heaters which simulate the thermal output of canisters of radioactive waste. Because most rock mecha… more
Date: December 1, 1979
Creator: Schrauf, T.; Pratt, H.; Simonson, E.; Hustrulid, W.; Nelson, P.; DuBois, A. et al.
Partner: UNT Libraries Government Documents Department
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Mossbauer effect and neutron diffraction study of the anomalous lattice behavior of U/sub 6/Fe

Description: Neutron diffraction and /sup 57/Fe Moessbauer effect measurements have been made on the exchange-enhanced superconductor U/sub 6/Fe. The neutron diffraction results indicate a pronounced anisotropy in the thermal expansion of the unit cell and an anomalous temperature dependence for the c-axis component of the total Debye-Waller factor of Fe below 100K. The Moessbauer effect measurements show non-Debye behavior in the mean-squared displacement of Fe, with phonon hardening occurring below 100K. … more
Date: June 1, 1985
Creator: Vaishnava, P. P.; Dwight, A. E.; Kimball, C. W.; Jorgensen, J. D. & Fradin, F. Y.
Partner: UNT Libraries Government Documents Department
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A simple model for radial expansion reactivity in LMRs (liquid metal reactors)

Description: Presented in this report is a simple analytical model developed for evaluating the radial expansion reactivity in small modular liquid metal reactors (LMRs). The present model is based on a non-leakage representation of the effective neutron multiplication factor. The resultant analytical expression for the radial expansion reactivity is simple and can be used directly in a system code for safety analyses. Applications of the present model to PRISM and SAFR resulted in a good agreement with the… more
Date: January 1, 1988
Creator: Cheng, H.S. & Van Tuyle, G.J.
Partner: UNT Libraries Government Documents Department
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Fuel cells: applied research fuel cell materials and electrocatalysis. Annual report, January 1976--December 1976

Description: Research is described on electrocatalysis of fuel cell reactions including the topics (1) mixed oxides as oxygen electrodes, (2) electrolyte effects on the oxygen reduction reaction, (3) anion effects on the oxygen reduction reaction, and (4) selection and evaluation of electrocatalysts for oxygen reduction in KHCO/sub 3//K/sub 2/CO/sub 3/ buffered electrolytes. Phosphoric acid fuel cell studies include inhibition of sintering of fuel cell catalyst particles: electrochemical methods for surface… more
Date: September 1, 1977
Creator: Srinivasan, S. & Isaacs, H. S.
Partner: UNT Libraries Government Documents Department
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Thermoelectric materials evaluation program. Technical summary report

Description: Research progress on the thermoelectric materials evaluation program is reported covering the period January 1, 1976 to September 30, 1978. Topical reports are presented on (1) hot and cold end ..delta..T's, (2) hardware mobility, (3) p-leg sublimation suppression, (4) thermodynamic stability of p-legs, (5) n-leg material process improvements to reduce extraneous resistance, (6) n-leg cracking, (7) dynamic evaluation of converter, and (8) data base and degradation modes. Twenty attachments are … more
Date: April 1979
Creator: Hinderman, J.D.
Partner: UNT Libraries Government Documents Department
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Physical properties of kraft black liquor. Final report. Phase I

Description: Methods were selected, equipment installed, and procedures developed for determining rheological properties; for determining thermal properties (stability, density, thermal expansion, and heat capacity); for purification and characterization of lignin (glass transition, stability, weight average molecular weight, and number average molecular weight); and for performing chemical analyses (negative inorganic ions, positive inorganic ions, acid organic salts, lignin, and total solids). A strategy … more
Date: December 1, 1983
Creator: Fricke, A.L.
Partner: UNT Libraries Government Documents Department
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Cross-hole investigation of a rock mass subjected to heating

Description: A cross-hole high-frequency acoustic investigation of a granitic rock mass subjected to sustained heating is reported. Compressional and shear-wave velocity measurements along four different paths between four vertical boreholes made prior to turning on the heater, during 398 days of heating and after the heater was turned off correlated well with the presence of fracture zones, in which the fractures were closed by thermal expansion of the rock upon heating. When the rock mass cooled, the velo… more
Date: April 1, 1980
Creator: Paulsson, B.N.P. & King, M.S.
Partner: UNT Libraries Government Documents Department
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Thermal properties measurements on rocksalt samples from the site of the proposed Waste Isolation Pilot Plant

Description: Thermal conductivity, thermal expansion, and specific heat measurements have been made on a number of specimens. The specific heat measurements were made by differential scanning calorimetry and the results showed that the specific heats of both clean rocksalt samples and of dirty samples with less than or equal to 7% insoluble impurities were essentially identical to the published specific heat for pure NaCl. In the thermal expansion measurements, two distinct groups of samples were identified… more
Date: May 13, 1980
Creator: Sweet, J. N. & McCreight, J. E.
Partner: UNT Libraries Government Documents Department
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Silicon-on ceramic process. Silicon sheet growth and device developmentt for the Large-Area Silicon Sheet Task of the Low-Cost Solar Array Project. Quarterly report No. 13, October 1-December 31, 1979

Description: Research on the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating inexpensive ceramic substrates with a thin layer of polycrystalline silicon is reported. The coating methods to be developed are directed toward a minimum-cost process for producing solar cells with a terrestrial conversion efficiency of 11 percent or greater. By applying a graphite coating to one face of a ceramic substrate, molten silicon can be caused to wet only that graphite-coated f… more
Date: February 15, 1980
Creator: Chapman, P W; Zook, J D; Grung, B L; McHenry, K & Schuldt, S B
Partner: UNT Libraries Government Documents Department
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Rapid regulatory control of plant cell expansion and wall relaxation

Description: The aim of this project is to elucidate the biophysical and cellular mechanisms that control plant cell expansion. At present we are attempting to characterize the kinetics of the system(s) responsible for regulatory and compensatory behavior of growing cells and tissues. This work is significantly because it indicates that biochemical loosening and biophysical stress relaxation of the wall are part of a feedback loop controlling growth. This report briefly summarizes the efforts and results of… more
Date: August 14, 1991
Creator: Cosgrove, D.J.
Partner: UNT Libraries Government Documents Department
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