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Severe accident core heatup transients in modular high temperature gas-cooled reactors without operating Reactor Cavity Cooling Systems

Description: The ultimate decay heat removal system for the current Modular High Temperature Gas-Cooled reactors is a completely passive natural convection air cooling loop. This paper considers an extremely remote accident scenario, where even this passive system fails, and heat rejection is only via a layer of thermal insulation to the reactor silo structure and the surrounding soil. The results show that even in this case the peak fuel temperatures remain well within safe limits. However, vessel and conc… more
Date: January 1, 1988
Creator: Kroeger, P. G.
Partner: UNT Libraries Government Documents Department
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Impact of Nonequilibrium Particle Temperature Considerations on Seeded Coal Combustion Plasma Properties

Description: This past quarter ending 12/30/91, the linear MHD channel simulation model has not only been completely specified but also fully modified to incorporate considerations for nonequilibrium particle temperatures. Testing of the modified model with the initial values from the first submodel (Richter's combustion zone model) and evaluation of the non-equilibrium particle temperature effect on the overall MHD performance is being held up. Reasons for the holdup is the lack of adequate response from D… more
Date: January 1, 1991
Creator: Oni, A. A.
Partner: UNT Libraries Government Documents Department
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Phosphate-bonded glass cements for geothermal wells. Final report

Description: Calcium aluminosilicate glasses were found to react with phosphoric acid in three ways depending upon silica content. Above 55% SiO/sub 2/ they are insoluble while below 50% they dissolve readily. The transition compositions release calcium and aluminum ions and a silica gel phase replaces the glass. Activation energies in the order of 10 kcal/mole are associated with the dissolution. Equilibrium studies in the systems CaO-P/sub 2/O/sub 5/-H/sub 2/O, Al/sub 2/O/sub 3/-P/sub 2/O/sub 5/-H/sub 2/O… more
Date: September 1, 1979
Creator: Rockett, T.J.
Partner: UNT Libraries Government Documents Department
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Investigation of joining techniques for advanced austenitic alloys

Description: Modified Alloys 316 and 800H, designed for high temperature service, have been developed at Oak Ridge National Laboratory. Assessment of the weldability of the advanced austenitic alloys has been conducted at the University of Tennessee. Four aspects of weldability of the advanced austenitic alloys were included in the investigation.
Date: May 1, 1991
Creator: Lundin, C. D.; Qiao, C. Y. P.; Kikuchi, Y.; Shi, C. & Gill, T. P. S.
Partner: UNT Libraries Government Documents Department
open access

Summary of HTGR (high-temperature gas-cooled reactor) benchmark data from the high temperature lattice test reactor

Description: The High Temperature Lattice Test Reactor (HTLTR) was a unique critical facility specifically built and operated to measure variations in neutronic characteristics of high temperature gas cooled reactor (HTGR) lattices at temperatures up to 1000{degree}C. The Los Alamos National Laboratory commissioned Pacific Northwest Laboratory (PNL) to prepare this summary reference report on the HTLTR benchmark data and its associated documentation. In the initial stages of the program, the principle of th… more
Date: October 1, 1989
Creator: Newman, D.F.
Partner: UNT Libraries Government Documents Department
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Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983

Description: The objectives were: (1) to characterize samples D1, 10% FeO/90% MnO, and D2, 48% FeO/52% MnO, under varying conditions of reduction (at 250/sup 0/C or 350/sup 0/C in H/sub 2/) and of syngas reaction 1:1 of CO:H/sub 2/ at 290/sup 0/C) and in some cases use CO only for reduction and to identify species by Moessbauer Spectroscopy and Magnetization (sigma/sub s) measurement; (2) similarly, to see if there is any metal (oxide)/support (Mordenite) interaction by the same techniques. The characteriza… more
Date: November 1, 1983
Creator: Mulay, L.N.
Partner: UNT Libraries Government Documents Department
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Isolation of pathogenic Naegleria from artificially heated waters

Description: Investigations were undertaken to determine whether heated waters facilitate the proliferation of free-living amoeba that cause primary amoebic meningoencephalitis. Water samples were taken close to the discharges of power plants situated on lakes or rivers in Florida and Texas and from cooling towers in Tennessee. The water temperatures ranged from 29 to 42/sup 0/C. Water samples were also taken from several lakes in Florida and Texas without associated power plants. The water temperatures of … more
Date: January 1, 1977
Creator: Tyndall, R L; Willaert, E; Stevens, A R & Coutant, C C
Partner: UNT Libraries Government Documents Department
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Prediction of temperature increases in a salt repository expected from the storage of spent fuel or high-level waste

Description: Comparisons in temperature increases incurred from hypothetical storage of 133 MW of 10-year-old spent fuel (SF) or high-level waste (HLW) in underground salt formations have been made using the HEATING5 computer code. The comparisons are based on far-field homogenized models that cover areas of 65 and 25 sq miles for SF and HLW, respectively, and near-field unit-cell models covering respective areas of 610 ft/sup 2/ and 400 ft/sup 2/. Preliminary comparisons based on heat loads of 150 kW/acre … more
Date: April 1, 1978
Creator: Llewellyn, G.H.
Partner: UNT Libraries Government Documents Department
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Investigation of Celotex trademark charring depths in the DT-18 shipping container

Description: Celotex {trademark}, the insulating material used between the outer and inner containers of the DT-18 shipping package, undergoes decomposition, combustion, or both when heated to temperatures exceeding 150{degrees}C. Several DT-18 packages that had previously undergone hypothetical thermal accident testing were opened and Celotex {trademark} charring depths ranging from {1/2} to 1 {1/2} in. were recorded. The majority of char depth data taken was between 3/4 and 1 {1/4} in. One-dimensional HEA… more
Date: March 1, 1992
Creator: Anderson, J.C.
Partner: UNT Libraries Government Documents Department
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Phase-change thermal energy storage: Final subcontract report

Description: The research and development described in this document was conducted within the US Department of Energy's Solar Thermal Technology Program. The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors o… more
Date: November 1, 1989
Partner: UNT Libraries Government Documents Department
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Impact of Nonequilibrium Particle Temperature Considerations on Seeded Coal Combustion Plasma Properties

Description: The first of the three tasks of this research activity is to develop a model that represents steady, nonequilibrium energy interactions between post-combustion entrained particles and carrier gases, under typical coal-fired MHD operating conditions. The second task is to use the developed model to evaluate, for both the MHD linear channel and disk configurations. the impact of nonequilibrium particle temperatures on predicted gasdynamic and electrical property values that depend, at times criti… more
Date: January 1, 1992
Creator: Oni, A. A.
Partner: UNT Libraries Government Documents Department
open access

Effects of temperature on the absolute permeability of consolidated sandstone

Description: The effect of temperature on absolute permeability has been a point of disagreement in the petroleum literature for many years. Recent work at Stanford University has shown no dependence on temperature of the absolute permeability to water of unconsolidated sand cores. The objective of this report is to extend the investigation to consolidated sandstone by following similar experimental procedures and observing whether any temperature effects exist. Fontainebleau sandstone was chosen as the cor… more
Date: April 1, 1984
Creator: McKay, W.I. & Brigham, W.E.
Partner: UNT Libraries Government Documents Department
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Photoproduction of hydrogen by membranes of green photosynthetic bacteria

Description: Photoproduction of H/sub 2/ from ascorbate by unit-membrane vesicles from Chlorobium limicola f. thiosulfatophilum was achieved with a system containing gramicidin D, tetramethyl-p-phenylenediamine, methyl viologen, dithioerythritol, Clostridium hydrogenase, and an oxygen-scavenging mixture of glucose, glucose oxidase, ethanol, and catalase. Maximum quantum yield was less than one percent. Half maximum rate of H/sub 2/ production occurred at a white-light intensity of approximately 0.15 cm/sup … more
Date: January 1, 1980
Creator: Bernstein, J D & Olson, J M
Partner: UNT Libraries Government Documents Department
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Modeling of coupled geochemical and transport processes: An overview

Description: Early coupled models associated with fluid flow and solute transport have been limited by assumed conditions of constant temperature, fully saturated fluid flow, and constant pore fluid velocity. Developments including coupling of chemical reactions to variable fields of temperature and fluid flow have generated new requirements for experimental data. As the capabilities of coupled models expand, needs are created for experimental data to be used for both input and validation. 25 refs.
Date: October 1, 1989
Creator: Carnahan, C.L.
Partner: UNT Libraries Government Documents Department
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Lack of immediate effects from the 1979-80 Imperial and Victoria earthquakes on the exploited Cerro Prieto geothermal reservoir

Description: In 1979-1980 two large earthquakes of local magnitude (M/sub L/) greater than 6.0 occurred near the Cerro Prieto geothermal field. It has been suggested that related to these seismic events there was an abrupt temperature increase in the wells completed in the shallow (alpha) reservoir. A careful study of the geochemistry of the produced fluids, as well as a cursory reservoir engineering analysis, cannot confirm either the data or the hypothesis of a massive influx of hot water into the system … more
Date: June 1, 1986
Creator: Truesdell, A.H. & Lippmann, M.J.
Partner: UNT Libraries Government Documents Department
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Thermally Induced Structural Changes in Coal Combustion

Description: The effect of particle shape on char burnout is investigated in the limit of shrinking core combustion. As a first step, the particle temperature is assumed to proceed in the shrinking core regime and under conditions of negligible Stefan flow. The problem then reduces to calculating the oxygen concentration field around a non-spherical particle with the oxidation reaction taking place on the external surface. This problem has been addressed by an analytical technique and a numerical technique.… more
Date: January 17, 1990
Creator: Gavalas, G. R. & Flagan, R. C.
Partner: UNT Libraries Government Documents Department
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Electroless nickel and ion-plated protective coatings for silvered glass mirrors

Description: A preliminary examination of two methods of protecting second surface silvered glass mirrors from environmental degradation is presented. One method employed silver mirrors overcoated with Al, Ni, 304 stainless steel, Cr, or an Al/Cu alloy prepared by ion-plating. The other method used conventional wet process silver mirrors protected with a thin electroless nickel coating. No attempt was made to optimize the coatings for either method. These experimental mirrors were compared with conventional… more
Date: April 1, 1982
Creator: Lind, M. A.; Chaudiere, D. A.; Dake, L. S. & Stewart, T. L.
Partner: UNT Libraries Government Documents Department
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Seismic velocities and attenuation in an underground granitic waste repository subjected to heating

Description: The behavior of a granitic rock mass subjected to thermal load has been studied by an acoustic cross-hole technique between four boreholes, over a period of some two years. Velocities between boreholes were obtained from the times-of-flight of pulses of acoustic waves between transducers clamped to the borehole wall. The attenuation was obtained by a spectral ratios technique. When the heater was turned on, the velocities increased rapidly to an asymptotic value. When the heater was turned off,… more
Date: March 1, 1984
Creator: Paulsson, B.N.P. & King, M.S.
Partner: UNT Libraries Government Documents Department
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Magnetic multilayer interface anisotropy

Description: Ni/Mo and Ni/V multilayer magnetic anisotropy has been investigated as a function of Ni layer thickness, frequency and temperature. Variable frequency ferromagnetic resonance (FMR) measurements show, for the first time, significant frequency dependence associated with the multilayer magnetic anisotropy. The thickness dependence allows one to extract the interface contribution from the total anisotropy. Temperature dependant FMR (9 GHz) and room temperature magnetization indicate that strain bet… more
Date: January 1, 1991
Creator: Pechan, M. J.
Partner: UNT Libraries Government Documents Department
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An analysis of grazing incidence metal mirrors in a laser ICF reactor driver

Description: Grazing incidence metal mirrors (GIMMs) are examined to replace dielectric mirrors for the final elements in a laser beam line for an inertial confinement fusion reactor. For a laser driver with a wavelength from 250 to 500 nm in a 10-ms pulse, irradiated mirrors made of Al, Al alloys, or Mg were found to have calculated laser damage limits of 0.3--2.3 J/cm{sup 2} of beam energy and neutron lifetime fluence limits of over 5 {times} 10{sup 20} 14 MeV n/cm{sup 2} when used at grazing incidence an… more
Date: July 12, 1991
Creator: Bieri, R. & Guinan, M.
Partner: UNT Libraries Government Documents Department
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Inert Electrodes Program fiscal year 1988 annual report

Description: The Inert Electrodes Program, being conducted by Pacific Northwest Laboratory (PNL), involves improving the Hall-Heroult cells used by the Aluminum Industry for the electrochemical production of aluminum. The PNL research centers on developing more energy efficient, longer-lasting anodes and cathodes and ancillary equipment. Major accomplishments for Fiscal Year 1988 are summarized below. 14 refs., 56 figs., 9 tabs.
Date: October 1, 1989
Creator: Strachan, D.M.; Marschman, S.C.; Davis, N.C.; Friley, J.R. & Schilling, C.H.
Partner: UNT Libraries Government Documents Department
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Development of biomass gasification to produce substitute fuels

Description: The development of an efficient pressurized, medium-Btu steam-oxygen-blown fluidized-bed biomass gasification process was conducted. The overall program included initial stages of design-support research before the 12-ton-per-day (TPD) process research unit (PRU) was built. These stages involved the characterization of test-specific biomass species and the characteristics and limits of fluidization control. Also obtained for the design of the adiabatic PRU was information from studies with benc… more
Date: March 1, 1988
Creator: Evans, R. J.; Knight, R. A.; Onischak, M. & Babu, S. P.
Partner: UNT Libraries Government Documents Department
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Expected environments in high-level nuclear waste and spent fuel repositories in salt

Description: The purpose of this report is to describe the expected environments associated with high-level waste (HLW) and spent fuel (SF) repositories in salt formations. These environments include the thermal, fluid, pressure, brine chemistry, and radiation fields predicted for the repository conceptual designs. In this study, it is assumed that the repository will be a room and pillar mine in a rock-salt formation, with the disposal horizon located approx. 2000 ft (610 m) below the surface of the earth.… more
Date: August 1, 1980
Creator: Claiborne, H.C. & Rickertsen, L.D., Graham, R.F.
Partner: UNT Libraries Government Documents Department
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