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The Energy Gap in Nuclear Matter

Description: The magnitude of the energy gap in nuclear matter associated with a highly correlated ground state of the type believed to be important in the theory of superconductivity has been evaluated theoretically. The integral equation of Cooper, Mills, and Sessler is linearized and transformed into a form suitable for numerical solution. The energy gap, calculated by using an appropriate single-particle potential and the Gammel-Thaler two-body potential, is found to be a very strong function of the density of nuclear matter, and of the effective mass at the Fermi surface. It is concluded that the magnitude of the energy gap for nuclear matter should not be compared directly with experimental values for finite nuclei, although the results suggest that if the theory is extended to apply to finite nuclei it probably would be in agreement with experiment.
Date: January 31, 1960
Creator: Emery, V. J. & Sessler, A. M.
Partner: UNT Libraries Government Documents Department
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Weapons Effects for Protective Design

Description: A lecture intended to provide a general background in weapons effects is presented. Specific areas of nuclear explosion phenomena pertinent to the design of hardened systems discussed include nuclear radiation and shielding, fireball growth and effects, thermal radiation, air blast, cratering and throwout, ground shock effects, fallout, and afterwinds. (J.R.D.)
Date: March 31, 1960
Creator: Brode, H. L.
Partner: UNT Libraries Government Documents Department
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An Evaluation of Data on Nuclear Carbides

Description: Data on the properties, constitution, compatibility, radiation behavior, fabrication, preparation, storage, and handling of uranium, thorium, and plutonium carbides are reviewed. 187 references. (C.J.G.)
Date: May 31, 1960
Creator: Rough, F.A. & Chubb, W. eds.
Partner: UNT Libraries Government Documents Department
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Sub-Cooled Burnout Relative to Hanford Reactors

Description: In the Hanford production reactors, failure of fuel element cladding is known as subcooled burnout since the bulk coolant temperature is below the saturation temperature at time of failure or burnout of the fuel cladding. The heat generation rate at which subcooled burnout occurs, establishes a limit to allowable reactor power level. This document compares present and potential power level limits at the Hanford production reactors with power level limits established by subcooled burnout.
Date: May 31, 1960
Creator: Carlson, P. A. & Trumble, R. E.
Partner: UNT Libraries Government Documents Department
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USE OF SILICON SURFACE-BARRIER COUNTERS IN FAST-NEUTRON DETECTION AND SPECTROSCOPY

Description: A neutron-sensitive semiconductor counter was constructed by depositing a thin layer of Li/sup 6/F between two silicon surface-barrier counters. Neutrons are detected by observing the alpha + T pair resulting from the Li/sup 6/(n, alpha )T reaction; pulses from the two counters are added, and the sum pulse is amplified and recorded on a multichannel analyzer. Since the sandwich geometry permits simultaneous detection of both reaction products, the magnitude of the resulting sum pulse is proportional to the energy of the incoming neutron. Pulse-height spectra from slow neutrons and monoenergetic fast neutrons. in the energy region 0.6 to 3.5 Mev, were recorded from two counters of this type; in both counters the sensitive area was about 0.7 cm/sup 2/, with a Li/sup 6/F layer of order 150 mu g/cm thick. In all cases. a well defined neutron peak was observed in the pulse-height spectrum. In a typical case the full width at half maximum of the fast-neutron peak was about 300 kev. Counters of this type are relatively insensitive to background effects, notably gamma rays, and thus may prove to be useful in the detection and spectroscopy of fast neutrons. (auth)
Date: May 31, 1960
Creator: Love, T A & Murray, R B
Partner: UNT Libraries Government Documents Department
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Coolant backup design study basis and objective

Description: Preliminary studies have, in general, indicated the need for modifications and improvements to the reactor last ditch coolants systems in order to provide adequate safety of operation at power levels programmed for the future. These studies have indicated the need for improved reliability as well as increased capacity for the last ditch coolant systems. A design study is being prepared by Reactor Modification Design to define the scope of the modifications required to provide adequate last ditch systems for the older areas. Adequate last ditch cooling will be provided for the 100-K Areas under Project CGI-844 which is currently in progress. The purpose of this document is to set forth the operating conditions and objectives on which the study will be based.
Date: August 31, 1960
Creator: Schack, M. H. & Tupper, W. J.
Partner: UNT Libraries Government Documents Department
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Design of production test IP-344-A-FP, determination of the limitations of the Al-Si process

Description: Tests in which aluminum-jacketed, Al-Si bonded uranium fuel elements were baked at various temperatures have shown there is a time-temperature relationship for Al-Si layer decomposition. For heat transfer and secondary coolant barrier considerations, the extent of bonding layer deterioration during fuel element irradiation is important. Currently, Al-Si bonded fuel elements show evidence of spire bond separation, and to a lesser degree, can bond separation following irradiation. Such evidence has aroused concern for the ability of the currently produced Al-Si bonded fuel elements to withstand future reactor operating conditions. Several potential uranium fabrication and canning process improvements are being developed to further advance fuel element stability and performance. Optimization of process conditions based on these improvements may provide the necessary margin of safety for good bond layer integrity. Before a decision can be made to continue improvement of the present process or convert to a new canning process, more information on the stability of the present fuel element bond is needed. This report presents the design of a test to more fully evaluate Al-Si bond integrity under anticipated future reactor operating conditions.
Date: August 31, 1960
Creator: Hodgson, W. H. & Clinton, M. A.
Partner: UNT Libraries Government Documents Department
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Applied Mathematics Division Summary Report for July 1, 1958 Through June 30, 1959

Description: The objective of the Applied Mathematics Division is to provide mathematical assistance to other scientists in the Lab. This goal is achieved by (1) conducting research in numerical analysis and other branches of mathematics, (2) providing mathematical consultation, and (3) operating a computational service, using both digital and analog machines. Publications, papers, seminars, lectures, and courses are listed. A summary listing of computer programs developed or in progress is given. (For preceding period see AHL-5954.) (W.D.M)
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department
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Applied Mathematics Division Summary Report for July 1, 1959 Through June 30, 1960

Description: A summary of each computer program initiated during the report period together with code symbols indicating the extent to which information concerning the program is readily available are given. Programs previously reported are included if changes were made or additional information concerning them was placed in the program library. Abstracts of 704 newsletters and GEORGE bulletins are presented. (For preceding period see ANL-6089.) (W.D.M.)
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department
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CHEMICAL ENGINEERING DIVISION SUMMARY REPORT FOR JANUARY, FEBRUARY, AND MARCH 1957

Description: Fluoride Volatilization Separations Process. Development of a fused fluoride process for dissolution of uranium-- zirconium fuel alloys continued. In corrosion tests to find a suitable container material, Ni was found to be susceptible to a sulfur-type attack. Hastelloy B showed promise, and graphite offers excellent chemical resistance but poor mechanical strength. The dissolution rate of Zr in NaF-- ZrF as affected by impingement of the HF sparge was studied. Production of UF/sub 6/ by fluidized bed fluorination of UF/sub 4/ from ore concentrates was studied. The preparation, melting point, vapor pressure, and vapor density of UF/sub 5/ are given. Preliminary dissolution and recovery runs in semi-works equipment are discussed. Fluidization. Fluidized- bed techniques have been applied to conversion of UO/sub 2/(NO/sub 3/)/sub 2/ to UF/sub 4/ and to calcination of radioactive liquid wastes. Activities of the Green Salt Pilot Plant and shakedown runs of the shielded waste calciner are described. Reactor Chemistry. Studies continued on the kinetics and mechanism of oxidation of U, Th, and Zr. Data are given for oxidation of U in oxygen from 125 to 295 tained C and 20 to 800 mm pressure, and for Zr from 400 to 900 tained C and 200 nan O/sub 2/ pressure. The ratio of capture to fission cross sections for U/sup 233/ and U/sup 238/ in EBR-I have been determined as a function of position. ChemicalMetallurgical Separations Processes. Development of pyrometullurgical processing of spent reactor fuels continued. Work is repcrted on: melt refining and casting of U--Pu; iodine volatility problem; the system U--B-- Ta; the distribution coefficients for Pu between U--Cr and Mg and U and Mg; extraction of Pu from U by liquid Mg; Ce removal by dross refining; adsorption of volatilized metuls on surface active materials; and fractional crystallization of U with Zn. Analytical Research. A study …
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department
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CHEMICAL ENGINEERING DIVISION SUMMARY REPORT FOR JANUARY, FEBRUARY, MARCH 1960

Description: Chemical-Metalluaical Processing. A direct-cycle fuelreprocessing plant using pyrometallurgical procedures is being designed as part of the Experimental Breeder Reactor No. II project. The reduction of uranium oxide was investigated, using pure Mg and solntions of Mg in Zn and Cd. Cadinium solntions of U were shown to be stable in Types 405 and 410 stainless steel containers at temperatures up to 550 deg C. The liquid metal corrosion loop in which a U-Mg--Cd alloy is being circulated at 550 deg C has been in trouble-free operation for 3000 hrs. Recovery of Pu from Mg solution by distillation of Mg was demonstrated on 1-g Pu scale. The solubility of Th in liquid Cd was measured over the temperature range from 1.9 x 10/sup -3/ per cent at 348 deg C to 1.8 x 10/sup -2/ per cent at 658 deg C. The solubility of Mn in liquid Cd was found to range from 0.27% at 414 deg C to 1.43% at 661 deg C. The solubility of Ni in liquid Cd was measured. The partition of U between liquid Al and liquid Cd was studied as a function of U concentration. The reaction of Al with a liquid Cd solution containing U, Zr, and Ce was studied. The free energy of formation of the U--Pb intermetallic compound UPb/sup 3/ was measured between 374 and 846 deg C by means of a galvanic cell method. Magnetic susceptibility measurements on the intermetallic comPound CeCd/sub 11/ were made over a range of temperature from 4 to 295 deg K. Fuel Cycle Applications of Volatility and Fluidization Techniques. The Direct Fluorination Process is currently aimed toward the processing of the Zircaloyclad, UO/sub 2/ fuel typical of the Dresden Reactor. The direct fluorination of dense UO/sub 2/ pellets submerged in an inert fluidized medium was carried …
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department
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ELK RIVER REACTOR. Quarterly Project Report for June-July-August 1959

Description: Progress is summarized on fuel element development, control rods and drives, reactor vessel and components. shielding, instrumentation, reactor building, plant facilities, and construction at site. (See also ACNP-ERR-3.) (W.D.M.)
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department
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Elk River Reactor Quarterly Project Report for September-October-November 1959

Description: With the project design work virtually complete, progress during the quarter consisted primarily of prccurement, fabrication of components, and construction at the reactor site. Developments are briefly summarized in the fuel element program, core physics vessel and internal components, control rods and rod drives, shielding, process, instrumentation, building and facilities, and construction. (For preceding period see ACNP-ERR-5.) (W.D.M.)
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department
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Fuel Element Catastrophe Studies Hazards of Fission Product Release From Irradiated Uranium

Description: The rate of reaction of highly irradiated U with air, CO/sub 2/, and steam was studied in sn investigation of the fission product release potential in a loss-of-coolant type accident postulated for Pu-producing reactors. Highly irradiated U was found to be more reactive, probably because of the defects in the oxide coating formed by the inclusion of fission products. Complete oxidation or melting was found to release rare gases, I, and Te semi- quantitatively in most atmospheres. Other fission products (Ru, Cs, and Sr) were released to a lesser extent and apparently in proportion to the amount of self- heating induced. In order of their relative tendency to release fission products, the atmospheric conditions investigated were rated in the order: air > CO/sub 2/ > steam. (auth)
Date: October 31, 1960
Creator: Parker, G. W.; Creek, G. E.; Martin, W. J. & Barton, C. J.
Partner: UNT Libraries Government Documents Department
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FUEL ELEMENT DEVELOPMENT PROGRAM FOR THE PEBBLE BED REACTOR. Quarterly Progress Report for November 1, 1959 to January 31, 1960

Description: A variety of spherical uranium--graphite fuel elements for the Pebble Bed Reactor (PBR) was fabricated. Poor results with sintered alumina coated UO/ sub 2/ particles led to the development of slumina coating by vspor deposition, for which good results have been obtained. A variety of sub-surface metal, metal carbide, and ceramic coatings located between an unfueled graphite shell and the fueled core of a PBR fuel element was prepared and examined. Most of the materials and processes showed poor results. Excellent metal recoveries were achieved from the metal oxide--graphite system using the grind-leach technique of reprocessing. Test results on Si-- SiC coated fuel elements showed good fission product retention in neutron activation tests, a self-welding tendency between adjacent spheres at 2500 deg F surface temperature, and no evidence of failure when an interanl gas pressure of 300 psi was applied. Fission product release rates from a pyrolytic carbon coated specimen under low-level irradiation were obtained at 150 to 1900 deg F. The design of the in-pile loop to study the behavior of fission products escaping from PBR fuel elements wss established. (C.J.G.)
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department
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