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Irradiation Processing Department Monthly Report: September 1960

Description: This document details activities of the irradiation processing department during the month of September, 1960. A general summary is included at the start of the report, after which the report is divided into the following sections: research and engineering operations; production and reactor operations; facilities engineering operation; employee relations operation; and financial operation.
Date: October 12, 1960
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Debye-Waller factors of the light actinide metals

Description: Time-of-flight neutron powder diffraction was used to determine the Debve-Waller factors of light actinide metals. The Debye-Waller factor is a measure of the mean-square atomic displacement that arises from the thermal motion ofthe atoms in any solid. Its temperature dependence determines a Debye-Waller temperature, {Theta}{sub DW}, that is characteristic of the elastic properties of the solid. The data are obtained by Rietveld analysis of neutron diffraction powder patterns obtained at severa… more
Date: October 1, 1993
Creator: Lawson, A. C.; Goldstone, J. A.; Cort, B.; Sheldon, R. I. & Foltyn, E. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure and phase transformations in uranium metal

Description: In common with other elemental actinides, metallic uranium exists in several allotropic forms, differing from one another by complex but subtle atomic rearrangements. This article reviews progress in understanding the successive phase transformations from the perspective of soft-mode instabilities.
Date: December 1, 1993
Creator: Axe, J. D.; Gruebel, G. & Lander, G. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Corrosion of U{sub x}Zr{sub 1-x}C{sub 1-y} nuclear fuel materials in hydrogen gas at high pressures and temperatures

Description: This paper describes the thermodynamics and kinetics of the corrosion of U{sub x}Zr{sub 1-x}C{sub 1-y} in hydrogen gas. It describes how corrosion rates are influenced by variables such as pressure, temperature, and gas flow rate. A model is developed which agrees with experimental steady state corrosion rates at 1 atm between 2670 and 3100 K. Under these conditions the corrosion flux is rate limited by the vapor phase transport of Zr(g) away from the solid surface to the bulk gas stream where … more
Date: June 1, 1992
Creator: Butt, D. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fission gas bubble nucleated cavitational swelling of the alpha-uranium phase of irradiated U-Pu-Zr fuel

Description: Cavitational swelling has been identified as a potential swelling mechanism for the alpha uranium phase of irradiated U-Pu-Zr metal fuels for the Integral Fast Reactor being developed at Argonne National Laboratory. The trends of U-Pu-Zr swelling data prior to fuel cladding contact can be interpreted in terms of unrestrained cavitational driven swelling. It is theorized that the swelling mechanisms at work in the alpha uranium phase can be modeled by single vacancy and single interstitial kinet… more
Date: April 1, 1992
Creator: Rest, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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IFR fuel cycle

Description: The next major milestone of the IFR program is engineering-scale demonstration of the pyroprocess fuel cycle. The EBR-II Fuel Cycle Facility has just entered a startup phase, which includes completion of facility modifications and installation and cold checkout of process equipment. This paper reviews the development of the electrorefining pyroprocess, the design and construction of the facility for the hot demonstration, the design and fabrication of the equipment, and the schedule and initial… more
Date: April 1, 1992
Creator: Battles, J. E.; Miller, W. E.; Lineberry, M. J. & Phipps, R. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A mechanistic model for radiation-induced crystallization and amorphization in U{sub 3}Si

Description: Radiation-induced amorphization is assessed. A rate-theory model is formulated wherein amorphous clusters are formed by the damage event These clusters are considered centers of expansion (CE), or excess-free-volume zones. Simultaneously, centers of compression (CC) are created in the material. The CCs are local regions of increased density that travel through the material as an elastic (e.g., acoustic) shock wave. The CEs can be annihilated upon contact with CCs (annihilation probability depen… more
Date: June 1, 1994
Creator: Rest, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Burning weapons-grade plutonium in reactors

Description: As a result of massive reductions in deployed nuclear warheads, and their subsequent dismantlement, large quantities of surplus weapons- grade plutonium will be stored until its ultimate disposition is achieved in both the US and Russia. Ultimate disposition has the following minimum requirements: (1) preclude return of plutonium to the US and Russian stockpiles, (2) prevent environmental damage by precluding release of plutonium contamination, and (3) prevent proliferation by precluding pluton… more
Date: June 1, 1993
Creator: Newman, D. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Molten aluminum alloy fuel fragmentation experiments

Description: Experiments were conducted in which molten aluminum alloys were injected into a 1.2 m deep pool of water. The parameters varied were (i) injectant material (8001 aluminum alloy and 12.3 wt% U-87.7 wt% Al), (ii) melt superheat (O to 50 K), (iii) water temperature (313, 343 and 373 K) and (iv) size and geometry of the pour stream (5, 10 and 20 mm diameter circular and 57 mm annular). The pour stream fragmentation was dominated by surface tension with large particles ({approximately}30 mm) being f… more
Date: September 1, 1992
Creator: Gabor, J. D.; Purviance, R. T.; Cassulo, J. C. & Spencer, B. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetic resonance as a structural probe of a uranium (VI) sol-gel process

Description: NMR investigations on the ORNL process for sol-gel synthesis of microspherical nuclear fuel (UO{sub 2}), has been useful in sorting out the chemical mechanism in the sol-gel steps. {sup 13}C, {sup 15}N, and {sup 1}H NMR studies on the HMTA gelation agent (Hexamethylene tetramine, C{sub 6}H{sub l2}N{sub 4}) has revealed near quantitative stability of this adamantane-like compound in the sol-Gel process, contrary to its historical role as an ammonia source for gelation from the worldwide technica… more
Date: December 31, 1989
Creator: King, C. M.; Thompson, M. C.; Buchanan, B. R.; King, R. B. & Garber, A. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear fuels for very high temperature applications

Description: The success of the development of nuclear thermal propulsion devices and thermionic space nuclear power generation systems depends on the successful utilization of nuclear fuel materials at temperatures in the range 2000 to 3500 K. Problems associated with the utilization of uranium bearing fuel materials at these very high temperatures while maintaining them in the solid state for the required operating times are addressed. The critical issues addressed include evaporation, melting, reactor ne… more
Date: August 1, 1992
Creator: Lundberg, L. B. & Hobbins, R. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of Uranium Atomic Vapor Laser Isotope Separation Program

Description: This report discusses demonstrations of plant-scale hardware embodying AVLIS technology which were completed in 1992. These demonstrations, designed to provide key economic and technical bases for plant deployment, produced significant quantities of low enriched uranium which could be used for civilian power reactor fuel. We are working with industry to address the integration of AVLIS into the fuel cycle. To prepare for deployment, a conceptual design and cost estimate for a uranium enrichment… more
Date: June 1, 1993
Creator: Chen, Hao-Lin & Feinberg, R. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application of diode lasers to the isotopically selective determination of uranium in oxides by optogalvanic spectroscopy

Description: We have observed isotopically selective diode laser-excited optogalvanic effects in uranium at 778.42 and 776.19 nm. The samples were natural abundance uranium oxide, as well as depleted (0.3% {sup 235}U), natural (0.7% {sup 235}U) and enriched (9.75% {sup 235}U) uranium metal or powders. The measurements were carried out in a demountable-cathode glow discharge cell. Preliminary evaluations of precision for uranium isotopic ratios measured using this technique suggest that it should have broad … more
Date: September 1, 1994
Creator: Young, J. P.; Barshick, C. M.; Shaw, R. W. & Ramsey, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A real-time monitoring/emergency response modeling workstation for a tritium facility

Description: At Lawrence Livermore National Laboratory (LLNL) we developed a real-time system to monitor two stacks on our tritium handling facility. The monitors transmit the stack data to a workstation which computes a 3D numerical model of atmospheric dispersion. The workstation also collects surface and upper air data from meteorological towers and a sodar. The complex meteorological and terrain setting in the Livermore Valley demands more sophisticated resolution of the three-dimensional structure of t… more
Date: July 1, 1993
Creator: Lawver, B. S.; Sims, J. M. & Baskett, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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LEU {sup 99}Mo target fabrication and testing: Overview, status, and plans

Description: As part of the RERTR program, the development of technology to use low-enriched uranium (LEU) for production of the fission product {sup 99}Mo has continued. Progress in fabrication development and out-of-pile thermal testing of targets based on uranium metal foils is summarized. Uranium foil of 125 {mu}m (0.005 in.) thickness has been fabricated. Heat treatments have been developed to provide a random crystal structure, which is required for satisfactory irradiation properties. Two target desi… more
Date: September 1, 1994
Creator: Wiencek, T. C.; Hofman, G. L.; Wood, E. L.; Wu, C. T. & Snelgrove, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synthesis of (U,Zr)C solid solutions under exothermic conditions

Description: The reactions of forming (U,Zr)C solid solutions from their elemental components or similarly less stable reactants such as UC{sub 2} are strongly exothermic due to the high stability of these solid solutions. A simple approach of utilizing this heat of formation energy to assist the solid solution reaction process is to intimately mix the less stable reactant powders and then pressed them into a compact. The compact is then heated to the ignition temperature of the reaction. The feasibility of… more
Date: August 20, 1993
Creator: Wang, L. L.; Moore, H. G. & Gladson, J. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Water film thickness effects from automatic fire sprinklers

Description: The study of water film thickness effects from automatic fire sprinklers is necessary because DOE recently mandated the use of automatic fire protection for the Fuel Fabrication Facility at the Savannah River Site (SRS). The primary nuclear criticality safety concern with overhead automatic fire sprinkler systems is the coating effect (film) as it spreads over the fissile material surface. This would affect nuclear criticality safety because moderating materials (water, plastic, and paper) are … more
Date: December 31, 1991
Creator: Ross, R. H.; Honkonen, D. L. & Salaymeh, S. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling of UO{sub 2} aqueous dissolution over a wide range of conditions

Description: Previously it was not possible to predict reliably the rate at which spent fuel would react with groundwater because of conflicting data in the literature. The dissolution of the UO{sub 2} spent fuel matrix is a necessary step for aqueous release of radioactive fission products. Statistical experimental design was used to plan a set of UO{sub 2} dissolution experiments to examine systematically the effects of temperature (25--75C), dissolved oxygen (0.002--0.2 atm overpressure), pH (8--10) and … more
Date: November 1, 1993
Creator: Steward, S. A. & Weed, H. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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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: July 1, 1992
Creator: Snelgrove, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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