54 Matching Results

Search Results

Advanced search parameters have been applied.


Description: A survey was made to select the construction materials for the SDR-1 reactor core vessel and grid plates. Hastelloy C was selected for the reactor vessel, top grid plate, and bottom grid plate. Inconel X was selected for the core hold-down springs. (C.J.G.)
Date: April 11, 1960
Creator: Facha, J.V.
Partner: UNT Libraries Government Documents Department


Description: The general requirements for the SNAP Reactor Cores include the fabrication of fuel elements. These elements consist nominally of 90 wt% zirconium-10 wt% highly enriched uranium (93% U/sup 235/) rods hydrided to an NH of 6.0-6.5 and machined. Alloying will be accomplished by triple arc melting. Forming will be done by extrusion, massive hydriding by techniques developed at Atomics International, and cladding by conventional means. (auth)
Date: December 11, 1963
Creator: Kirsch, T.S.
Partner: UNT Libraries Government Documents Department

Revised Thermal Analysis of LANL Ion Exchange Column

Description: This document updates a previous calculation of the temperature distributions in a Los Alamos National Laboratory (LANL) ion exchange column.1 LANL operates two laboratory-scale anion exchange columns, in series, to extract Pu-238 from nitric acid solutions. The Defense Nuclear Facilities Safety Board has requested an updated analysis to calculate maximum temperatures for higher resin loading capacities obtained with a new formulation of the Reillex HPQ anion exchange resin. The increased resin loading capacity will not exceed 118 g plutonium per L of resin bed. Calculations were requested for normal operation of the resin bed at the minimum allowable solution feed rate of 30 mL/min and after an interruption of flow at the end of the feed stage, when one of the columns is fully loaded. The object of the analysis is to demonstrate that the decay heat from the Pu-238 will not cause resin bed temperatures to increase to a level where the resin significantly degrades. At low temperatures, resin bed temperatures increase primarily due to decay heat. At {approx}70 C a Low Temperature Exotherm (LTE) resulting from the reaction between 8-12 M HNO{sub 3} and the resin has been observed. The LTE has been attributed to an irreversible oxidation of pendant ethyl benzene groups at the termini of the resin polymer chains by nitric acid. The ethyl benzene groups are converted to benzoic acid moities. The resin can be treated to permanently remove the LTE by heating a resin suspension in 8M HNO{sub 3} for 30-45 minutes. No degradation of the resin performance is observed after the LTE removal treatment. In fact, heating the resin in boiling ({approx}115-120 C) 12 M HNO{sub 3} for 3 hr displays thermal stability analogous to resin that has been treated to remove the LTE. The analysis is based on a previous study of ...
Date: April 11, 2006
Creator: Laurinat, J
Partner: UNT Libraries Government Documents Department

Oak Ridge Metals and Ceramics Division Annual Progress Report: 1963

Description: Report documenting research and developments made by the Metals and Ceramic Division of the Oak Ridge National Laboratory. Progress is reported on fundamental research in: crystal physics, reactions at metal surfaces, spectroscopy of ionic media, structure of metals, theory of alloying, physical properties, sintering, deformation of crystalline solids, x ray diffraction, metallurgy of superconducting materials, and electron microscope studies. Long-randge applied research studies were conducted for: zirconium metallurgy, materials compatibility, solid reactions, fuel element development, mechanical properties, non-destructive testing, and high-temperature materials. Reactor development support work was carried out for: gas-cooled reactor program, molten-salt reactor, high-flux isotope reactor, space-power program, thorium-utilization program, advanced-test reactor, Army Package Power Reactor, Enrico Fermi fast-breeder reactor, and water desalination program. Other program activities, for which research was conducted, included: thermonuclear project, transuraniunn program, and post-irradiation examination laboratory. Separate abstracts were prepared for 30 sections of the report. (B.O.G.)
Date: November 11, 1963
Creator: Oak Ridge National Laboratory. Metals and Ceramics Division.
Partner: UNT Libraries Government Documents Department

Analysis of Density Changes in Plutonium Observed from Accelerated Aging Using Pu-238 Enrichment

Description: We present dimensional and density changes in an aging plutonium alloy enriched with 7.3 at.% of {sup 238}Pu and reference alloys of various ages. After 45 equivalent years of aging, the enriched alloys at 35 C have swelled in volume by 0.14 to 0.16% and now exhibit a near linear volume increase, without void swelling. Based on X-ray diffraction measurements, the lattice expansion by self-irradiation appears to be the primary cause for dimensional changes during the initial 2-3 years of aging. Following the initial transient, the density change is primarily cause by a constant helium in-growth rate as a result of {alpha}-particle decay.
Date: July 11, 2006
Creator: Chung, B. W.; Saw, C. K.; Thompson, S. R.; Quick, T. M.; Woods, C. H.; Hopkins, D. J. et al.
Partner: UNT Libraries Government Documents Department

Final report for FY 1965 on tungsten--uranium dioxide materials for NASA. Part I. Preparation of high purity uranium oxide powders. Part II. Cladding and joining of tungsten cermets by plasma spraying. Part III. Tungsten coating of uranium dioxide particles

Description: Declassified 28 Aug 1973. Several uranium oxide fuel materials were prepared for evaluation. Included was a 2-pound sample of plasma jet spheroidized. 30- to 60- mu UO/sub 2/ of precisely controlled stoichiometry containing less than 50 ppM metallic impurities. Six 1-pound samples of 30- to 60- mu U0/sub 2/ were prepared which contained calcium oxide, thorium oxide, or yttrium oxide stabilizing agents in solid solution. These powders were coated with 8 to 10 mu of tungsten by hydrogen reduction of tungsten hexaflouride in a fluidized bed. Seven 1-pound samples of 30- to 60- mu U0/sub 2/ containing various concentrations of yttrium oxide in solid solution were also prepared. Finally, a 1-pound sample of less than 5- mu UO/sub 2/ containing 10 mole% yttrium oxide was produced. Procedures were developed for applying metallurgically bonded tungsten coatings to the edges of W-U0/sub 2/ cermet fuel elements. These coatings were effective in reducing the U0/sub 2/ loss in high- temperature tests at NASA. Of several techniques examined for producing a halide- free tungsten coating on 30- to 60- mu U0/sub 2/ powder. the most promising were (a) vacuum evaporation of tungsten using electron beam heating, and (b) electrostatically bonding fine WO/sub 2/ powder onto the UO/sub 2/, followed by conversion to tungsten by hydrogen reduction. (auth)
Date: October 11, 1965
Creator: Cochran, W.L.; Knight, R.G. & Stanley, F.S.
Partner: UNT Libraries Government Documents Department


Description: A total of 74 subsections are included in the report. The information in 4 subsections was previously abstracted in NSA. Separate abstracts were prepared for 38 of the subsections. Those sections for which no abstracts were prepared contain information on prompt neutron lifetime, Rover critical experiments, Pu/sup 239/ fission, neutron decay, the O5R code, alpha scattering, 8 and P wavelengths, proton scattering, deuteron scattering, local optical potentials, N. S. Savamah radiation leakage, reactor shielding, cross section data analysis, gamma transport, gamma energy deposition, gaussian integration, data interpolation, neutron scattering, neutron energy deposition, space vehicles, computer analyses, shielding, positron sources, and secondary particles. (J.R.D.)
Date: January 11, 1963
Partner: UNT Libraries Government Documents Department

Four Group Cross Sections

Description: At the present, 16- and 23-energy-group calculations are impractical for 2-dimensional-diffusion or transport calculation or for 1-dimensional transport survey calculations. For this reason a set of 4-group cross sections were obtained for cores with spectral characteristics similar to SNAP 2 or SNAP 8. The results of calculations using these cross sections are compared with the results using a 23-group set. The comparison is satisfactory for the values predicted for k eff and for the power distributions. The method for obtaining the cross sections is also presented and because of the ease of obtaining new sets, it is expected that many refinements in the present set and computation of new sets for cases requiring a different spectrum will be made at the discretion of the user. (auth)
Date: October 11, 1962
Creator: Colston, B. W.
Partner: UNT Libraries Government Documents Department

Encapsulation of ThO$sub 2$ in molybdenum liners via hot pressing

Description: Encapsulation of ThO/sub 2/ powder in molybdenum liners using hot pressing techniques was demonstrated. ThO/sub 2/ was used as a simulant for /sup 238/PuO/sub 2/. Five discs were hot pressed in an effort to establish die design and pressing parameters. Dies were designed to receive cups made of 0.005-in. or 0.031-in. molybdenum. Pressing temperatures of 1850 deg C and 1450 deg C were tried. A ThO/sub 2/ disc of 88% theoretical density was successfully hot pressed inside a cup fabricated from 0.031-in. molybdenum. The disc was pressed at 1850 deg C and 3800 psi. (auth)
Date: October 11, 1973
Creator: Pardieck, W.D.
Partner: UNT Libraries Government Documents Department