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Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Description: Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m wit… more
Date: January 1, 1978
Creator: Thomas, R. G. & Smith, D. M.
Partner: UNT Libraries Government Documents Department
open access

Interaction of noble-metal fission products with pyrolytic silicon carbide

Description: Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain layers of pyrolytic carbon and silicon carbide, which act as a miniature pressure vessel and form the primary fission product barrier. Of the many fission products formed during irradiation, the noble metals are of particular interest because they interact significantly with the SiC layer and their concentrations are somewhat higher in the low-enriched uranium fuels currently under consideration. To study fission product-… more
Date: January 1, 1982
Creator: Lauf, R. J. & Braski, D. N.
Partner: UNT Libraries Government Documents Department
open access

Hot cell studies of tritium removal from and dissolution of an irradiated thoria fuel

Description: Tritium removal and dissolution studies on an irradiated thoria-based fuel were conducted in the High Level Caves at the Savannah River Laboratory (SRL). The objectives of these studies were to define the effects of key process-related parameters on tritium evolution and subsequent dissolution. The test program at SRL determined the effects on tritium removal of particle size, heating temperature, oxidation, and agitation. ThO/sub 2//UO/sub 2/ (95%/5%) fuel from the Elk River Reactor, irradiate… more
Date: January 1, 1980
Creator: Pickett, J.B.
Partner: UNT Libraries Government Documents Department
open access

Investigation of breached depleted UF sub 6 cylinders

Description: In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF{sub 6}, two 14-ton cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. An investigation team was immediately formed to determine the cause of the failures and their impact on future storage procedures and to recommend corrective actions. Subsequent investigation showed that the failures most probably resulted from mechanical damage that oc… more
Date: January 1, 1991
Creator: DeVan, J. H.
Partner: UNT Libraries Government Documents Department
open access

Analysis of the thorium axial blanket experiments in the PROTEUS reactor

Description: An extensive program of reactor physics experiments in GCFR fuel pin lattices has been completed recently at the PROTEUS critical facility located at EIR laboratory in Switzerland. The PROTEUS reactor consists of a central test zone surrounded by a uranium buffer and thermal driver region. The test lattices included a PuO/sub 2//UO/sub 2/ fuel region with internal and axial blankets of UO/sub 2/, ThO/sub 2/, and thorium metal. Detailed analysis of the thorium-bearing lattices has been performed… more
Date: January 1, 1980
Creator: White, J.R.; Ingersoll, D.T. & Schmocker, U.
Partner: UNT Libraries Government Documents Department
open access

Preparation of curium-americium oxide microspheres by resin-bead loading

Description: Resin-bead loading and calcination techniques have been used to produce all curium and americium oxide feed material (about 2.2 kg) for HFIR targets since 1971. The process based on Dowex 50W resin has progressed from a series of test runs, through special production runs, into routine production in permanent equipment beginning in 1975. Key attributes of this process are its reliability, high yields, and ease of operation. The process is suited for remote operation in hot cells. Yields approac… more
Date: January 1, 1980
Creator: Chattin, F. R.; Benker, D. E.; Lloyd, M. H.; Orr, P. B.; Ross, R. G. & Wiggins, J. T.
Partner: UNT Libraries Government Documents Department
open access

Thermodynamics of the Fuel Fragmentation Gas

Description: In the context of nuclear reactor safety studies, a program is in progress at ORNL whereby fuel-fragmentation situations are mocked up by the application of high-current capacitor discharges through solid UO/sub 2/ samples. The goal of the present work is to predict such quantities as the number of gas and liquid fragments and their energy distributions. The point of view adopted is that upon fragmentation, a cloud of UO/sub 2/ vapor is formed containing ''primeval'' liquid fragments which act … more
Date: January 1, 1977
Creator: Perez, R. B. & Alsmiller, R. G., Jr.
Partner: UNT Libraries Government Documents Department
open access

Uranium hexafluoride: Safe handling, processing, and transporting: Conference proceedings

Description: This conference seeks to provide a forum for the exchange of information and ideas of the safety aspects and technical issue related to the handling of uranium hexafluoride. By allowing operators, engineers, scientists, managers, educators, and others to meet and share experiences of mutual concern, the conference is also intended to provide the participants with a more complete knowledge of technical and operational issues. The topics for the papers in the proceedings are widely varied and inc… more
Date: January 1, 1988
Creator: Strunk, W.D. & Thornton, S.G. (eds.)
Partner: UNT Libraries Government Documents Department
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Phonon dispersion relation of uranium nitrate above and below the Neel temperature

Description: Neutron coherent inelastic scattering measurements have been made of the phonon dispersion relation of uranium nitride both above and below the Neel temperature T/sub N/ = 50 K. Within the precision of the measurements, about 1% in frequency and 10% in line width and in scattered neutron intensity, no significant changes in these phonon properties were observed as a function of temperature other than those arising from population factor changes and a small stiffening of the lattice as the tempe… more
Date: January 1, 1977
Creator: Dolling, G; Holden, T M; Evensson, E C; Buyers, W J.L. & Lander, G H
Partner: UNT Libraries Government Documents Department
open access

New computer-controlled precipitator at the Savannah River Plant

Description: A new plutonium triflouride preciptation facility was successfully started up on the first attempt May 13, 1987 at the Savannah River Plant (SRP). This new facility provided a 75% reduction in radiation exposure, a substantial improvement in process performance, and elimination of the major SRP process bottleneck. This was accomplished through sound engineering, improved process control, process automation, and extensive testing of components, assemblies, and entire system prior to ''… more
Date: January 1, 1988
Creator: Moore, E. N.; Robbins, C. C. & Murdock, D. W.
Partner: UNT Libraries Government Documents Department
open access

End of life fission product distributions in F-1 experiment fuel rods

Description: Fission product migration and end-of-life distributions were examined in the F-1 (X094) series of sealed, mixed-oxide fuel rods irradiated in the fast flux of EBR-II. Cesium, rubidium, iodine, and strontium data obtained from axial gamma scanning, mass spectrometry, and radiochemical analyses are presented. The results show significant migration of cesium, probably as both a volatile species and as the noble gas precursor. Cesium metal species leaving the fuel region accumulate predominately at… more
Date: May 1, 1980
Creator: Goodin, D. T.; Langer, S. & Bell, W. E.
Partner: UNT Libraries Government Documents Department
open access

Magnetic susceptibility of AnRe/sub 2/ compounds

Description: The compounds AnRe/sub 2/, where An = Th, U, Np, and Pu all have the MgZn/sub 2/-type hexagonal Laves phase structure. Measurements of their magnetic susceptibilities have been made from 2-300 K. Whereas ThRe/sub 2/, URe/sub 2/, and PuRe/sub 2/ have essentially temperature-independent susceptibilities, NpRe/sub 2/ is ferromagnetic with T/sub c/ = 47 K. The paramagnetic data for NpRe/sub 2/ follow a modified Curie-Weiss law, chi-che/sub 0/ = C/(T-THETA) from 60-230 K with THETA = 46.9 K and C eq… more
Date: January 1, 1977
Creator: Brodsky, M. B.; Trainor, R. J.; Aldred, A. T. & Sowers, C. H.
Partner: UNT Libraries Government Documents Department
open access

Light water reactor fuel reprocessing: dissolution studies of voloxidized fuel

Description: Voloxidation is a proposed head-end process to remove tritium from irradiated LWR fuel by roasting the fuel in the presence of oxygen. The process oxidizes UO/sub 2/ to a fine U/sub 3/O/sub 8/ powder with high surface area for dissolution. Small-scale tests with irradiated Robinson, Oconee, and Saxton reactor fuels have been made to determine the dissolution behavior of both voloxidized and nonvoloxidized (UO/sub 2/) fuel. No significant technical problems were encountered in batch-dissolving o… more
Date: January 1, 1977
Creator: Johnson, D. R. & Stone, J. A.
Partner: UNT Libraries Government Documents Department
open access

RERTR Program fuel testing and demonstration: an update

Description: The irradiation and postirradiation examination of high-density, reduced-enrichment miniplates and full-sized elements are continuing under the RERTR Program. The emphasis is currently being placed on determining uranium-density/fission-density limits for the highest-density silicide fuels. One whole core demonstration is nearing completion in the FNR, and another, using U/sub 3/Si/sub 2/ fuel, is scheduled to begin in the ORR during the next year. This paper will summarize the progress made du… more
Date: January 1, 1984
Creator: Snelgrove, J. L.
Partner: UNT Libraries Government Documents Department
open access

Application of ultrasonic thermometry in LMFBR safety research

Description: Ultrasonic thermometry has many potential applications in reactor safety research, where extremely high temperatures and lack of visual access may preclude the use of conventional diagnostics. An application (the in-core molten fuel pool experiment) will be described in which thoriated tungsten ultrasonic thermometers were used to measure temperatures in UO/sub 2/ to incipient melt (2860/sup 0/). Each thermometer included five sensor elements 10 mm long, providing five temperatures within the U… more
Date: January 1, 1977
Creator: Carlson, G. A.; Sullivan, W. H. & Plein, H. G.
Partner: UNT Libraries Government Documents Department
open access

New chromatographic materials for the separation and concentration of uranium from environmental matrices

Description: Extraction chromatography, in which an inert support is impregnated with an extractant solution to form a chromatographic resin, combines the specificity of extraction with the ease of operation of an ion exchange column, thereby overcoming the principal drawbacks of the two methods when used alone. Previous work in this laboratory on the design of selective extractants for use in nuclear fuel reprocessing and in nuclear waste treatment has led to the development of several new phosphorus-based… more
Date: January 1, 1991
Creator: Horwitz, E.P.; Dietz, M.L.; Chiarizia, R. & Diamond, H.
Partner: UNT Libraries Government Documents Department
open access

Ir/PuO/sub 2/ compatibility: transfer of impurities from plutonium dioxide to iridium metal during high temperature aging

Description: Plutonium oxide fuel pellets for powering radioisotopic thermoelectric generators for NASA space vehicles are encapsulated in iridium which has been grain-boundary-stabilized with thorium and aluminum. After aging for 6 months at 1310/sup 0/C under vacuum, enhanced grain growth is observed in the near-surface grains of the iridium next to the PuO/sub 2/. Examination of the grain boundaries by AES and SIMS shows a depletion of thorium and aluminum. Iron, chromium, and nickel from the fuel were f… more
Date: January 1, 1984
Creator: Taylor, D. H.; Christie, W. H. & Pavone, D.
Partner: UNT Libraries Government Documents Department
open access

Voloxidation studies with UO/sub 2/ reactor fuels

Description: Voloxidation was studied experimentally in small-scale laboratory tests with irradiated UO/sub 2/ reactor fuels. The present study developed new data on the effects on the voloxidation reaction of hull length, oxygen concentration, temperature, agitation, fuel density, and fuel type and burnup. The reaction was studied by measuring weight gains, yields of U/sub 3/O/sub 8/, product densities and particle-size distributions, reaction rates, tritium release, and behavior of other off-gases (/sup 1… more
Date: January 1, 1980
Creator: Stone, J A
Partner: UNT Libraries Government Documents Department
open access

Voloxidation and dissolution of irradiated plutonium recycle fuels

Description: Voloxidation removed > 99.4% of the tritium in the fuels tested (LWR recycled fuels containing /sup 239/Pu). Voloxidation increased the amount of insoluble residue by roughly a factor of two. Voloxidation increased the amount of plutonium in the insoluble residue by factors of 4 to 5. Voloxidation made the insoluble plutonium much harder to dissolve.
Date: January 1, 1980
Creator: Cadieux, J.R. & Stone, J.A.
Partner: UNT Libraries Government Documents Department
open access

Fuel systems for compact fast space reactors

Description: About 200 refractory metal clad ceramic fuel pins have been irradiated in thermal reactors under the 1200 K to 1550 K cladding temperature conditions of primary relevance to space reactors. This paper reviews performance with respect to fissile atom density, operating temperatures, fuel swelling, fission gas release, fuel-cladding compatibility, and consequences of failure. It was concluded that UO/sub 2/ and UN fuels show approximately equal performance potential and that UC fuel has lesser po… more
Date: December 1, 1983
Creator: Cox, C.M.; Dutt, D.S. & Karnesky, R.A.
Partner: UNT Libraries Government Documents Department
open access

First in-core molten fuel pool experiment. [LMFBR]

Description: If during a LMFBR accident a fuel debris bed is not adequately cooled by overlying sodium and dryout occurs, then the fuel would heat up and melt. Molten fuel pools are of concern due to their potential for ablation of the supporting structure and possible penetration of the reactor vessel. The major goal of the molten fuel pool program has been to develop a versatile experiment in which heat flux and structural ablation could be studied using real materials under typical temperature and heatin… more
Date: January 1, 1977
Creator: Plein, H.G. & Carlson, G.A.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

A review of the U sub 3 O sub 8 -aluminum reaction as a potential heat source in research and test reactor accidents

Description: A critical review of the literature on the U{sub 3}O{sub 8}-aluminum reaction has been conducted. The reaction in fabricated fuel plates is found to be less energetic and much slower than in cold-pressed powder mixtures. The difference is at least partially attributable to conversion of up to 50% of the U{sub 3}O{sub 8} to U{sub 4}O{sub 9} during fabrication. No definitive measurements of the amount and rate of energy release have been made. Data are provided upon which to base calculations of … more
Date: January 1, 1992
Creator: Snelgrove, J.L.
Partner: UNT Libraries Government Documents Department
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