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Compilation of yields from neutron-induced fission of /sup 232/Th, /sup 235/U, /sup 236/U, /sup 237/Np, /sup 238/U, and /sup 239/Pu measured radiochemically at Los Alamos

Description: Radiochemically measured relative fission yields have been compiled for targets of /sup 232/Th, /sup 235/U, /sup 236/U, /sup 237/Np, /sup 238/U, and /sup 239/Pu that were irradiated with neutrons, the average energies of which were in the 0.0253-eV to 14-MeV range. The yields were examined for consistency by means of the two-mode-of-fission hypothesis. The circumstances associated with inconsistencies were investigated, but the yields in questions were rejected only when good cause was found. F… more
Date: October 1, 1975
Creator: Ford, G. P. & Norris, A. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Isotopic power materials development. Quarterly progress report for period ending December 31, 1976

Description: Research progress is reported on: (1) high-temperature alloys for space isotopic heat sources; (2) physical and mechanical metallurgy of heat source containment materials; (3) /sup 144/Cm fuel development; (4) terrestrial radioisotope applications; (5) selenide isotope generator system support; (6) isotope Brayton system materials support; and (7) space nuclear flight systems hardware. (TFD)
Date: June 1, 1977
Creator: Schaffhauser, A. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dissolution rates of /sup 238/PuO/sub 2/ and /sup 239/PuO/sub 2/ in 1M perchloric acid

Description: The dissolution rate of /sup 238/PuO/sub 2/ and /sup 239/PuO/sub 2/ in 1M HClO/sub 4/ was measured over a period of 200 days. When equal (150-..mu..g/l) masses of the oxides were compared, /sup 238/Pu was found to be released approximately five times faster than /sup 239/Pu. At the 10-..mu..Ci/ml activity level, /sup 238/Pu was released 100 times faster than /sup 239/Pu. The difference in dissolution rates is attributed to the difference in alpha particle specific activity of the two materials … more
Date: December 1, 1976
Creator: Matlack, G. M.; Patterson, J. H.; Nelson, G. B. & Waterbury, G. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

Description: This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. Two areas of radon pr… more
Date: July 1, 1992
Creator: Hopke, P. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status of beta- and gamma-decay and spontaneous-fission data from transactinium isotopes

Description: Several categories of ..beta..- and ..gamma..-related decay data for the transactinium isotopes are assessed in the light of their potential use in applied areas. The status as of August, 1975, of these data is summarized for 142 transactinium nuclides with 228 less than or equal to A less than or equal to 257 by the listing of experimental values and errors where known. Several useful compilations of transactinium-isotope decay data are discussed. Recent developments related to the yields and … more
Date: April 1, 1976
Creator: Reich, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-/sup 240/Pu sector experiments in ZPPR assembly 4

Description: The complete high-/sup 240/Pu fuel experiment in ZPPR assembly 4 is reviewed. Results of criticality, enrichment, small-sample perturbation, sodium void, /sup 238/U Doppler, control rod substitution and reaction rate measurements are presented. Comparison of these measured values with calculated results are included where possible. The relationship between the ZPPR high-/sup 240/Pu fuel experiments and the results obtained in previous critical experience is considered.
Date: December 1, 1976
Creator: McFarlane, H F & Beck, C L
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A consequence index approach to identifying radiological sabotage targets

Description: One of the threats of concern to facilities using significant quantities of radioactive material is radiological sabotage. Both the Department of Energy (DOE) and the US Nuclear Regulatory Commission have issued guidance to facilities for radiological sabotage protection. At those facilities where the inventories of radioactive materials change frequently, there is an operational need for a technically defensible method of determining whether or not the inventory of radioactive material at a gi… more
Date: June 26, 1988
Creator: Altman, Willard D. & Hockert, John W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spin quenching in the SO/sub 8/ and SP/sub 6/ fermion models of collective motion

Description: The SO/sub 8/ and SP/sub 6/ models assume that the low-lying collective states of heavy nuclei are dominated by collective pairs of fermions coupled to angular momentum j = 0/sup +/, 2/sup +/. These models are generalizations of the pairing model (SP/sub 2/) to include the quadrupole degree of freedom. The expectation value of the spin operator in the SO/sub 8/ and SP/sub 6/ models is studied. 2 refs., 1 tab. (DWL)
Date: January 1, 1986
Creator: Ginocchio, J. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Discovery of fermium-259. [Half life, cross sections]

Description: A 1.5-sec spontaneous fission activity was produced by irradiation of /sup 257/Fm with 16-MeV tritons at the Los Alamos Tandem Van de Graaff Facility. On the basis of cross section and fission systematics, this 1.5-sec activity was attributed to /sup 259/Fm formed by the reaction, /sup 257/Fm(t,p)/sup 259/Fm. /sup 259/Fm is the heaviest known isotope of fermium and has more neutrons than any other isotope so far identified. The mass distribution of the /sup 259/Fm is highly symmetric and the av… more
Date: January 1, 1976
Creator: Hoffman, D. C.; Weber, J.; Wilhelmy, J. B.; Hulet, E. K.; Landrum, J. H.; Lougheed, R. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Resonance computations for cells with fuel annuli

Description: Two methods have been developed for the computation of resonance integrals in cells containing annular fuel regions. Both are based on rational approximations. One is a generalization of a one-term rational approximation method developed by Segev for a cell with a single fuel annulus. The second modifies the earlier Chen-Gelbard two-term method originally used for double-heterogeneity calculations. Both methods were tested, in cells with two fuel annuli, for various U{sup 235} and U{sup 238} re… more
Date: January 1, 1990
Creator: Hwang, R. N. & Gelbard, E. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neutronic calculation and cross section sensitivity analysis of the Livermore mirror fusion/fission hybrid reactor blanket

Description: The neutronic calculation for the Livermore mirror fusion/fission hybrid reactor blanket was performed using the PPPL cross section library. Significant differences were found in the tritium breeding and plutonium production in comparison to the results of the LLL calculation. The cross section sensitivity study for tritium breeding indicates that the response is sensitive to the cross section of /sup 238/U in the neighborhood of 14 MeV and 1 MeV. The response is also sensitive to the cross sec… more
Date: August 1, 1977
Creator: Ku, L. P. & Price, W. G. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Integro-differential equation analysis and radioisotope imaging systems. Research proposal. [Testing of radioisotope imaging system in phantoms]

Description: Design modifications of a five-probe focusing collimator coincidence radioisotope scanning system are described. Clinical applications of the system were tested in phantoms using radioisotopes with short biological half-lives, including /sup 75/Se, /sup 192/Ir, /sup 43/K, /sup 130/I, and /sup 82/Br. Data processing methods are also described. (CH)
Date: March 9, 1976
Creator: Hart, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transuranic and tracer simulant resuspension. [/sup 238/Pu, /sup 239/Pu, /sup 240/Pu]

Description: Plutonium resuspension results are summarized for experiments conducted at Rocky Flats, onsite on the Hanford reservation, and for winds blowing from offsite onto the Hanford reservation near the Prosser barricade boundary. In each case, plutonium resuspension was shown by increased airborne plutonium concentrations as a function of either wind speed or as compared to fallout levels. All measured airborne concentrations were below maximum permissible concentrations (MPC). Both plutonium and ces… more
Date: July 1, 1977
Creator: Sehmel, G. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experimental program for the Fast Breeder Blanket Facility, FBBF

Description: The work performed in the reporting period was primarily concerned with the development of the experimental program (Task A) and with the pre-analysis of future loadings and the impact upon the permanent loading of the two converter regions, which contain 4.8 percent enriched UO/sub 2/ rods. It appears necessary that a neutron poison (B/sub 4/C) be placed in the converter (transformer) regions in order to hold, also for future loadings, the k/sub eff/ of a hypothetically flooded FBBF well below… more
Date: January 1, 1976
Creator: Ott, K. O.; Clikeman, F. M.; Johnson, R. H. & Borg, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Estimation of /sup 244/Cm intake by bioassay measurements following a contamination incident

Description: An employee was contaminated with radioactive material consisting primarily of /sup 244/Cm and /sup 246/Cm as a consequence of handling a curium nitrate solution at a reprocessing facility. In vivo gamma analysis and in vitro (urine and fecal) analysis were initiated soon after the incident. Further in vivo measurements were performed regularly through hour 528, and in vitro bioassay measurements were obtained through day 74. A sample of the curium solution from the workplace was obtained to co… more
Date: January 1, 1988
Creator: Thein, M.; Bogard, J. S. & Eckerman, K. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies of yttrium gettering efficiency in radioisotopic heat sources

Description: Compatibility specimens were fabricated using different fuel stoichiometries and yttrium shapes, sizes, and material lots to determine which would be the most efficient oxygen getter for use in heat sources. Evaluations were accomplished by comparison of metallography, microhardness, and oxygen and nitrogen analyses.
Date: January 1, 1976
Creator: Teaney, P. E. & Wise, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Enrichment supply and technology outside the United States

Description: This is a review of foreign uranium enrichment capacity and uranium isotope separation technology, based on news items and articles in the public literature. Tables are included presenting capacity plans, growth, sales, research and development, etc. (DLC)
Date: January 13, 1977
Creator: Levin, S. A. & Blumkin, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radionuclide content of an exhumed canyon vessel and neighboring soil. [Health hazards from long-time buried radiochemical process equipment]

Description: The long-term hazard potential associated with burial of process equipment from radiochemical separations plants is being evaluated. As part of this evaluation, a feed adjustment tank was exhumed eighteen years after burial. The tank had been in service in the fuel reprocessing plant for twenty-nine months before it was retired. Assay of the exhumed tank indicated that 7 mg (0.4 mCi) of /sup 239/Pu and 1 mCi of /sup 137/Cs remained on its surfaces; 1.1 mg (0.07 mCi) /sup 239/Pu, 0.4 mCi /sup 13… more
Date: November 1, 1976
Creator: Holcomb, H. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

Description: Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters. (LK)
Date: September 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resin-based preparation of HTGR fuels: operation of an engineering-scale uranium loading system

Description: The fuel particles for recycle of /sup 233/U to High-Temperature Gas-Cooled Reactors are prepared from uranium-loaded carboxylic acid ion exchange resins which are subsequently carbonized, converted, and refabricated. The development and operation of individual items of equipment and of an integrated system are described for the resin-loading part of the process. This engineering-scale system was full scale with respect to a hot demonstration facility, but was operated with natural uranium. The… more
Date: October 1, 1977
Creator: Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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