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Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating

Description: ent temperature variation in a thermally orthotropic plate which is subjected to an arbitrary heating rate distribution along one face with all other surfaces being insulated. Dimensionless temperature histories and distributions determined from this solution are presented for the special, but representative, case of a linearly varying heating rate distribution on plates with varying degrees of thermal orthotropy. These results establish quantitatively the value of a material with high planar a… more
Date: June 1, 1961
Creator: Hornbaker, David Ross
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Analysis of erosion and transport of carbon impurity in the TFTR inner bumper limiter region

Description: Carbon sputtering and transport on the TFTR inner graphite bumper limiter is investigated with the impurity transport code REDEP. Analysis is carried out for a series of ohmic discharges in TFTR. Predictions for Z{sub eff} in the core plasma agree well with in-situ experimental measurements. Run-away self-sputtering of carbon is predicted at low densities and high edge plasma temperatures when the limiter surface was purged of deuterium. Surface erosion and deposition is analyzed. In general, r… more
Date: January 1, 1992
Creator: Hua, T. Q. & Brooks, J. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Engineering considerations of the advanced free electron laser facility

Description: The Advanced Free-Electron Laser (AFEL) is being built at Los Alamos inside a large laboratory building. In addition to cost and available space considerations, several engineering issues affected the design of the AFEL and its facility. The 1300-MHz, 20-MeV electron linac required extensive radiation shielding and a short rf-waveguide run. Free-Electron Lasers (FEL) and photocathode-drive laser optics required a clean, constant temperature environment. New environmental, health, and safety (ES… more
Date: January 1, 1991
Creator: Meier, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synchrotron x-ray study of physisorbed films of mixtures of Ar and Xe on graphite

Description: Mixtures of Ar and Xe have been studied in most of the submonolayer region of the phase diagram (T,chi,rho), T = temperature, chi = chemical composition, rho = fraction of a monolayer. The basic feature is a large tendency to form ..sqrt.. 3 x ..sqrt.. 3 commensurate alloys (Kr-like structures), but none of the commensurate nor of the incommensurate structures form a chemically ordered alloy at 11 K. Thus the 2D solid can be thought of as a solid consisting of particles of an average size. This… more
Date: July 1, 1982
Creator: Bohr, J.; Nielsen, M.; McTague, J. P.; Als-Nielsen, J. & Kjaer, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Size effects in aerosol particle interactions: the van der Waals potential and collision rates

Description: Three effects which are explicitly dependent on aerosol particle size are identified and discussed. They are focussed about the particle collision rate and how it relates to the properties of the gas, the particle, and the particle's interaction potential energy which play roles in particle-particle collision rates. By incorporating the conduction electronic free path effect for conductors into the frequency-dependent dielectric constants of silver and graphite, particle size effects in th… more
Date: January 1, 1980
Creator: Marlow, W H
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Near-isotropic petroleum-coke based graphites for high temperature gas-cooled reactor core components

Description: The standard covers procurement requirements for extruded graphite logs, 15 in. (381 mm) or greater in diameter, manufactured with near-isotropic petroleum cokes and coal-tar pitch binders which are candidates or reference materials for replaceable fuel and reflector blocks for High-Temperature Gas-Cooled Reactors (HTGRs). The requirements are designed to produce the degree of lot-to-lot reproducibility which is required to ensure consistent and predictable properties and irradiation performanc… more
Date: October 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of carbonaceous materials using extraction with supercritical pentane

Description: The use of carbonaceous adsorbents is limited by irreversible adsorption of some compounds so the use of supercritical pentane as an extracting solvent was examined. Carbon black appeared to be broken down slowly, but continuously, by the penane. To see if other types of carbon behaved similarly, high purity graphite, technical grade graphites, active carbons, and charcoals were examined. The extracts were characterized by uv spectroscopy, packed column chromatography using flame ionization and… more
Date: May 30, 1980
Creator: Fetzer, J.C.; Graham, J.A.; Arrendale, R.R.; Klee, M.S. & Rogers, L.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thulium-170 heat source

Description: An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipe… more
Date: September 6, 1990
Creator: Walter, Carl E.; Van Konynenburg, Richard & VanSant, James H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

FUEL ELEMENT DEVELOPMENT PROGRAM FOR THE PEBBLE BED REACTOR. Final Report

Description: >The basic fuel element consisted of a uniform dispersion of fuel in a 1 1/2 inch diameter graphite sphere. Ceramic coatings for the retention of fission products were studied. It was found-that molecularly deposited'' ceramics such as alumina, siliconized silicon carbide, and pyrolytic carbon were excellent barriers to fission product leakage. The most advantageous location for ceramic coatings was found to be on the individual fuel particles, where the coating was subject to smaller forces an… more
Date: April 30, 1961
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal responses of tokamak reactor first walls during cyclic plasma burns

Description: The CINDA-3G computer code has been adapted to analyze the thermal responses and operating limitations of two fusion reactor first-wall concepts under normal cyclic operation. A component of an LMFBR computer has been modified and adapted to analyze the ablative behavior of first-walls after a plasma disruption. The first-wall design concepts considered are a forced-circulation water-cooled stainless steel panel with and without a monolithic graphite liner. The thermal gradients in the metal wa… more
Date: January 1, 1977
Creator: Smith, D. L. & Charak, I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Final report on Silicon halide-alkali metal flames as a source of solar grade silicon

Description: The object of this program was to determine the feasibility of using continuous high-temperature reactions of alkali metals and silicon halides to produce silicon in large quantities and of suitable purity for use in the production of photovoltaic solar cells. Equilibrium calculations showed that a range of conditions were available where silicon was produced as a condensed phase but the byproduct alkali metal salt was a vapor. A process was proposed using the vapor phase reaction of Na with Si… more
Date: January 1, 1980
Creator: Olson, D. B.; Miller, W. J. & Gould, R. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic Implications of Band Structure Effects for Rare Gases on Graphite

Description: Recent analyses of atomic beam scattering data have suggested that an anisotropic He-C pair interaction is appropriate to the problem of He on graphite. This results in considerably more corrugated equipotential surfaces than previously assumed, and correspondingly manifest band structure effects. These have been observed for He/graphite in the specific heat for temperature T > 3/sup 0/K. The implications for other gases and temperatures and for the effective adatom-adatom interaction are discu… more
Date: January 1, 1980
Creator: Carlos, W. E.; Cole, M. W.; Rauber, S.; Vidali, G.; Silva-Moreira, A. F.; Codona, J. L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Irradiation test OF-2: high-temperature irradiation behavior of LASL-made fuel rods and LASL-made coated particles. [ZrC coated particles]

Description: Three LASL-made, substoichiometric ZrC-coated particles with inert kernels, and two high-density molded graphite fuel rods that contained LASL-made, ZrC-coated fissile particles were irradiated in the Oak Ridge Research Reactor test OF-2. The severest test conditions were 8.36 x 10/sup 21/ nvt (E greater than 0.18 MeV) at 1350/sup 0/C. The graphite matrix showed no effect of the irradiation. There was no interaction between the matrix and any of the particle coats. The loose ZrC coated particle… more
Date: October 1, 1977
Creator: Wagner, P.; Reiswig, R. D.; Hollabaugh, C. M.; White, R. W.; O'Rourke, J. A.; Davidson, K. V. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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HTGR fuels and core development program. Quarterly progress report for the period ending November 30, 1977. [Graphite and fuel irradiation; fission product release]

Description: The work reported here includes studies of basic fission product transport mechanisms, core graphite development and testing, and the development and testing of recyclable fuel systems. Materials studied include irradiation capsule tests of both fuel and graphite. Experimental procedures and results are discussed and data are presented.
Date: December 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of plasma surface interactions on PLT plasma parameters

Description: This paper gives a brief description of the geometry and parameters of the PLT tokamak, reviews some of the last four years' results that are particularly relevant to plasma-boundary interactions, and then concentrates on two specific problems.
Date: July 1, 1980
Creator: Meservey, E.B.; Arunasalam, V. & Barnes, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

MHTGR: New production reactor summary of experience base

Description: Worldwide interest in the Modular High-Temperature Gas-Cooled Reactor (MHTGR) stems from the capability of the system to retain the advanced fuel and thermal performance while providing unparalleled levels of safety. The small power level of the MHTGR and its passive systems give it a margin of safety not attained by other concepts being developed for power generation. This report covers the experience base for the key nuclear system, components, and processes related to the MHTGR-NPR. 9 refs.,… more
Date: March 1, 1988
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The effects of specimen geometry and size on the fracture toughness of nuclear graphites

Description: In a joint Oak Ridge National Laboratory (ORNL)/Japan Atomic Energy Research Institute (JAERI) study, various fracture toughness techniques were applied to Toyo Tanso grade IG-110 graphite to establish if specimen geometry influences on fracture toughness. The test geometries investigated were: compact tension (CT), disc compact tension (DCT), short rod (SR), chevron-notched short-red (CNSR), cylindrical bend specimen (BS), and centrally slotted disc (CSD). Specimen geometries which allow slow … more
Date: January 1, 1991
Creator: Romanoski, G.R. & Burchell, T.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nondestructive evaluation of the oxidation and strength of the Fort Saint Vrain HTGR support block

Description: Non-destructive detection of changes in the strength of graphite support structures in a HTGR appears to be feasible using sonic velocity measurements where access for through transmission is possible. Therefore, future HTGR designs should consider providing such access. Where access is not available, strength changes can be correlated with oxidation profiles in the support member. These oxidation profiles can be determined non-destructively by a combination of eddy current measurements to dete… more
Date: April 1, 1982
Creator: Tingey, G. L.; Posakony, G. J.; Morgan, W. C.; Prince, J. M.; Hill, R. W. & Lessor, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of annular-coated-pressurized and sphere-pac LWR fuels

Description: Annular-coated (graphite)-pressurized and sphere-pac fuel rod designs, which are expected to exhibit improved PCI-failure resistance, and, thus, more reliable extended burnup performance, are being developed. Data sufficient to provide the technical bases needed to license lead test assemblies of the improved designs for irradiation in commercial LWRs are being obtained. Out-of-reactor experiments, in-reactor instrumented experiments, in-reactor power-ramp tests, and lead-rod demonstration irra… more
Date: December 1, 1981
Creator: Buckman, F. W.; Crouthamel, C. E.; Freshley, M. D. & Barner, J. O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thin films of gallium arsenide on low-cost substrates. Quarterly technical progress report No. 6 and topical report No. 2, January 1, 1978-April 1, 1978

Description: The metalorganic chemical vapor deposition (MO-CVD) technique has been applied to the growth of thin films of GaAs and GaAlAs on inexpensive polycrystalline or amorphous substrate materials (primarily glasses and metals) for use in fabrication of large-area low-cost photovoltaic device structures. Trimethylgallium (TMG), arsine (AsH/sub 3/), and trimethylaluminum (TMAl) are mixed in appropriate concentrations at room temperature in the gaseous state and pyrolyzed at the substrate, which is heat… more
Date: April 1, 1978
Creator: Ruth, R. P.; Dapkus, P. D.; Dupuis, R. D.; Campbell, A. G.; Johnson, R. E.; Manasevit, H. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gas-cooled reactor programs: High-Temperature Gas-Cooled Reactor Base-Technology Program. Annual progress report for period ending December 31, 1979

Description: Progress in HTGR studies is reported in the following areas: HTGR chemistry; fueled graphite development; prestressed concrete pressure vessel development; structural materials; HTGR graphite studies; and evaluation of the pebble-bed HTR.
Date: July 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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