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Analysis of Thorex Pilot Plant Radiation Exposures During 1955

Description: The Thorex Pilot Plant at Oak Ridge National Laboratory was operated during 1955, processing reactor-irradiated thorium slugs to recover U233 and thorium and 12 MTR fuel elements to recover U235 and Np237. The radiation exposure received by operating personnel during this period averaged 60 mrcp/man-week. Most radiation exposure was received in areas that were intended to be only slightly or nonradioactive. However, because insufficient decontamination of process solutions was achieved and equipment surfaces became contaminated from equipment failures, these areas became primary sources of personnel exposure. The installation of additional shielding where needed and the prompt removal of surface contamination successfully reduced the radiation levels and exposures in these areas. Remote control of processing equipment and sampling of very radioactive solutions from process equipment was successfully accomplished, and assisted in the reduction of exposure to operating personnel.
Date: November 16, 1956
Creator: McCarley W. T.
Partner: UNT Libraries Government Documents Department
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Metallurgy Division Semiannual Progress Report for Period Ending April 10, 1956

Description: Progress report of the Oak Ridge National Laboratory Metallurgy Division providing updates on various projects, experiments, and other work. This report includes a summary of scholarly output and summaries of general corrosion, dynamic corrosion, mechanical properties, nondestructive testing, welding and brazing, fabrication, physical chemistry of corrosion, HRP metallurgy, the package power reactor program, APPR absorber, metallurgical materials and processing, metallography, ceramics, fundamental physico-metallurgical research.
Date: November 2, 1956
Creator: Frye, J. H., Jr.; Manly, W. D. & Cunningham, J. E.
Partner: UNT Libraries Government Documents Department
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Electronuclear Research Division Semiannual Progress Report for Period Ending September 20, 1955

Description: The installations of the beam deflector in the ORL 86-inch Cyclotron is sufficiently complete to allow initial testing the system permits the optional use of high-current internal targets. A survey of [illegible] cross sections made with 14-Mev neutrons indicates qualitative agreement with statistical theory. An internal-conversion ion spectrograph and a fission-fragment spectrograph were built and put in operation. The [illegible] functions severed proton-induced reactions of possible use in isotope production were measured. A capsule-type target is being used for the irradiation of chemical compounds. Nuclear physics research with 26-Mev nitrogen lens from the ORNL 63-inch Cyclotron concerned the following: a theoretical interpretation of elastic nitrogen-nitrogen scattering a detailed investigation of some nitrogen-nitrogen nuclear reactions; the measurement of reactions across sections in boron and aluminum; and the identification and the energy spectre of protons and alpha particles resulting from nitrogen-induced reactions with light elements. A study is being made of the practicality of a fixed-frequency cyclotron to accelerate protons to about 1 [illegible] for application in [illegible] research. Phase compensation would be obtained with an unusual magnetic-field configuration which has eight [illegible] cycles with about 72 deg of spiral, Also, a proposal was made to convert the 44-in. proton cyclotron a new 48-in. magnet would permit the acceleration of heavy ions to energies up to 81 Mev.
Date: November 1955
Creator: Livingston, Robert S. & Howard, F. T.
Partner: UNT Libraries Government Documents Department
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Preliminary Results of APPR Critical Experiments, Part I.

Description: This memorandum is the first in a series reporting progress in the program of critical experiments in the ORNLArmy Package Power Reactor Project. The critical assembly, designated as CA-25, is analogous to the APPR design core and consists of 45 fuel boxes, in a 7 x 7 array with the corners removed, contaIned in a large water tank. Two sides of each box are slotted for the insertion and positioning of any desired loading of eighteen plates of fuel, structural material, and poison. The array is submerged in water to provide a moderated and reflector. Enriched uranium metal, in two-mil-thick foils 2.5 x 22 in, is encased in type 304 stainless steel sheets, 2.7 x 23 x 0.0105 in., to form fuel plates. Stainless steel plates, 2.7 x 23 x 0.025 in. are used to simulate additional steel in the APPR core. It is, therefore, possible to maintain an essentially constant metal to water ration in the assembly when the fuel content is varied. The fuel is distributed as uniformly as possible in all boxes and a symmetrical distribution of materials is maintained in the core at all times. Fuel plates containing half-width (1.25 in) uranium foils are provided for making small changes in loading
Date: November 25, 1955
Creator: Williams, D. V. P.
Partner: UNT Libraries Government Documents Department
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ORNL Mortal Recovery Plant: Processing of ORNL Graphite Reactor Fuel Elements During the Period July and August, 1955

Description: From July 7 to August 31, 1955, 20 tons of uranium and 1,200 g of plutonium were recovered in 47 days of plant operation at an average rate of 833 lb/day of uranium and at a cost of $2.60/lb of uranium. Uranium and plutonium recoveries were, respectively, 99.9 and 95.5 per cent.
Date: November 11, 1955
Creator: Brooksbank, R. E.; Chandler, J. M. & Hylton, C. D.
Partner: UNT Libraries Government Documents Department
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Determination of Traces of Uranium Metal by Decomposition of the Hydride

Description: Two methods were developed for the determination of uranium metal in UF3 with other fluoride compounds. A simplified method of determination which has a relatively high degree of precision (coefficient of variation 2 per cent) is carried out by decomposing the hydride in an atmosphere of carbon dioxide and subsequently measuring the hydrogen over an aqueous solution of potassium hydroxide. The ignition of the hydride in an atmosphere of oxygen and volumetric measurement of the water at reduced pressures provide a more sensitive method of determination. The coefficient of variation of the latter procedure is 7 per cent. The yield of gas from the reaction of the hydride with ammonia and gaseous hydrogen chloride was found to be neither stoichiometric nor reproducible.
Date: November 9, 1955
Creator: Meyer, A. S., Jr.; McDowell, B. L. & White, J. C.
Partner: UNT Libraries Government Documents Department
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Determination of Trivalent Uranium with Methylene Blue

Description: A direct titrimetric method for the determination of trivalent uranium in uranium trifluoride and mixtures of fused fluoride salts was developed. The method is based on the stoichiometric oxidation of trivalent uranium to the tetravalent oxidation state with an acidic solution of methylene blue. The sample containing trivalent uranium is dissolved at room temperature in an excess of standard methylene blue solution in a carbon dioxide atmosphere; the excess oxidant is variation of the method is 1.5 per cent for 5 mg quantities of trivalent uranium. The method was applied to various mixtures of fluoride salts containing both trivalent and tetravalent uranium.
Date: November 22, 1955
Creator: Ross, W. J.; Meyer, A. S.; White, J. C.; Kelley, N. T. & Susano, C. D.
Partner: UNT Libraries Government Documents Department
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Solid State Division Semiannual Progress Report for Period Ending August 31, 1955

Description: LITR Fluoride-Fuel Loop. — The inconel loop was dismantled for removal of the samples and for recovery of the uranium by using the remote cutting tools installed in a half cell of the Solid State Building. Disassembly proceeded without incident. An electric-arc cutting technique was developed for removal of the stainless steel enclosure around the pump bowl. Fission power and maximum flux were determined by irradiating a simulated loop, by heat-balance calculations, by radiochemical analyses for fission products in the fuel, by measuring the activation of cobalt foils attached to the loop, and by activation of the loop tubing itself. The determination of the power by these various methods gave 2.5 to 2.8 kw during operation of the loop, and the maximum power density was 0.4 kw/cc. Chemical analyses of the fuel were carried out to determine U, Zr, and the major constituents of inconel: Ni, Cr, and Fe.
Date: November 16, 1955
Creator: Billington, D. S. & Crawford, J. H., Jr.
Partner: UNT Libraries Government Documents Department
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An Evaluation of the Corrosion and Oxidation Resistance of High-Temperature Brazing Alloys

Description: The fabrication of heat exchangers and radiators to be used in conjunction with high-temperature nuclear reactors may present exceedingly complex problems. Rigid heat transfer requirements may necessitate the use of compact assemblies of thin-walled small-diameter tubes as integral parts of the heat transfer units. Intricate designs may also be required in which cooling fins must be securely joined to the tubes at closely spaced intervals. In addition to the difficulties in fabrication imposed by the designs themselves, the high operating temperatures involved require the careful selection of materials and joining techniques. The choice of fabrication procedure for a given component must not only be based upon the stresses and temperatures to be encountered, but also upon special factors peculiar to nuclear service. Since many reactor applications employ highly corrosive environments, compatibility of the structural ma terials with the corrosive media is of paramount importance. The low nuclear cross-section require ment for brazing alloys to be used inside the re actor also places stringent limitations on the possible choices of in-pile applications. The use of boron in alloys for certain service may not be considered feasible, for example, because of its high nuclear absorption cross section. Although welding is used extensively in the construction of radiators and heat exchangers, high-temperature brazing is also attractive for several applications. In Fig. 1, a photograph of a liquid-metal-to-air radiator, it can be seen that brazing serves as the most feasible method of attaching cooling fins to thin-walled tubes. Typical of the joints obtainable is that shown in Fig. 2, in which are shown stainless-steel-clad-copper high-conductivity fins2 brazed to an Inconel tube.
Date: November 7, 1956
Creator: Hoffman, E. E.; Leitten, C. F., Jr.; Patriarca, P.; Slaughter, G. M.; Pope, J. E.; Shubert, C. E. et al.
Partner: UNT Libraries Government Documents Department
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Homogeneous Reactor Project Quarterly Progress Report: For Period Ending October 31, 1954

Description: Part I. Experimental Reactors: The design has been completed for all the major high-pressure and low-pressure components except the reactor pressure vessel. Contained in this report are the most recent revisions of the low-pressure-system flow sheet, a description of important details of the reactor cell, and the final design of the main heat exchangers, the inner dump tanks and separator. the recombiner and recombiner-condenser, and the outer dump tank and reflux condenser. Part II. Thorium Breeder Reactor: An analysis of the relative effects of major process variables on the economics and characteristics of two-region thorium breeder reactors is nearing completion, and the results to date are presented in this report. From these results most of the major reactor characteristics have been determined; they are reported with certain other engineering studies pertinent to the early phases of the program. Part III. Corrosion: One loop was removed from service and cross sectioned for inspection of the internal surfaces. This loop was of type 347 stainless steel pipe and had a cumulative operating time of more than 12,000 hr with uranyl sulfate solutions varying in concentration from 0.004 to 1.34 m. No excessive or localized corrosion attack was noted except in one highly turbulent area immediately downstream from the in-line corrosion sample holder.
Date: November 1954
Creator: McDuffie, H. F. & Kelly, D. C.
Partner: UNT Libraries Government Documents Department
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Electronuclear Research Division Semiannual Progress Report

Description: Nuclear physics research with 22-Mev protons in the 86-in. cyclotron included angular-distribution measurements of neutrons from (p,n) reactions in nine target elements; measurement of the angular distribution of fission fragments from proton-induced fission of U233, U225, U228, Th230, and Th232; measurement of alpha-particle angular distributions from (p,α) reactions a study of the neutron-deficient isotopes of terbium and completion of an extensive program of the measurement of activation cross sections. Two more targets for cyclotron production of isotopes were developed, and the production yields for 14 radioisotopes are summarized. A new record for continuous beam power on a production target, 36 kw for 5 hr, was achieved. The design of a beam-deflector system for the 86-in. cyclotron has been completed, and several of the components have been fabricated ; a shutdown for installation is scheduled for October 8. The deflected N+++ beam of the 63-in. cyclotron was used in a study of the gain and loss of electrons by nitrogen lens passing through thin foils, and the equilibrium charge distribution of lens as a function of energy was thus obtained. The excitation functions were measured for nitrogen-induced reactions on both nitrogen and oxygen. Assembly restrictions of the prepared 114-in. heavy-particle cyclotron were continued, and on investigation of the possibility of converting the 44-in. cyclotron was initiated.
Date: November 18, 1954
Creator: Livingston, R. S. & Howard, F. T.
Partner: UNT Libraries Government Documents Department
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Servo System for Magnetic Controlled Constant Intensity Flat Top Beam Spill-Out

Description: A uniform intensity flat top spill-out cannot be obtained by manual control for two reasons: 1. The horizontal density of the internal beam of the Cosmotron is far from uniform. As a result, a manually controlled linear motion of the internal beam into a target will result in a non-uniform spill-out intensity. 2. Stability requirements of the Cosmotron magnet voltage are not easily met without feedback because of inherent component stability. The proposed servo system will sense the external beam intensity, and correct the magnet voltage to keep this intensity constant. This servo must operate through the transfer function of the main ignitron system and the flat top filter. Both of those transfer functions impose special problems.
Date: November 21, 1961
Creator: Cottingham, J. G.
Partner: UNT Libraries Government Documents Department
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Transient Reactor Aerothermodynamics

Description: The transient aerothermodynamic processes in a gas-cooled reactor are described in a simplified manner to illustrate some of the fundamental physical phenomena involved, to provide some approximate but useful methods of analysis, and to aid in the understanding and use of more complex computer solutions. The transient heat balance equation for an element of a single reactor channel is derived in terms of aerothermodynamic time constants, and typical analytic solutions for transients are presented. This equation is used in generating the time-dependent equation for the channel exhaust gas temperature. The single-channel analysis is extended to multiple channels. A method for determining the approximate transient temperature envelopes for various reactor components is presented. The effects of aerodynamic and thermal coupling between different reactor channels are illustrated. Some of the simplifying assumptions are investigated with respect to the conditions under which they are valid.
Date: November 18, 1963
Creator: Rodean, Howard C.
Partner: UNT Libraries Government Documents Department
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Some Applications of the Chase Two-Dimensional Analyzer at Brookhaven National Laboratory

Description: The Chase two-dimensional analyzer is a 64 channel by 64 channel analyzer with a magnetic drum memory and a buffered storage system. The memory capacity is 2 counts per channel. The maximum storage rate is limited by the drum speed and is about 800 counts per second for a featureless spectrum.
Date: November 6, 1962
Creator: Donovan, Paul F.
Partner: UNT Libraries Government Documents Department
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A Coated Cast Iron Crucible for use with Eutectic Al-Si Alloy in the Temperature Range 595°-650°C

Description: The feasibility of the coated metal crucible as a container for eutectic Al-Si alloy has been proven by test. Small, enamel-coated cast iron pots has been proven by test. Small, enamel-coated cast iron pots have successfully withstood the chemically aggressive Al-Si alloy and the adverse influence of an oxidizing atmosphere for a period of 3 months at 725°C. A similarly coated castiron crucible containing 450 pounds of eutectic Al-Si alloy was successfully tested for 144 days in a jacketing operation conducted at 595°-650°C. Under the same conditions, the normal service life of clay-bonded graphite and silicon carbide crucibles rarely exceeds 45 days. The coating material is a commercially available enamel capable of withstanding temperatures up to 790°C (1450°F). It is readily applied to the surface of a variety of ferrous metals and alloys; however, best results are obtained with alloys low in chromium and nickel which also have a low thermal expansion coefficient.
Date: November 1957
Creator: Yaggee, F. L.
Partner: UNT Libraries Government Documents Department
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Radiobiological Studies of the Columbia River Through December, 1955

Description: Radiobiological studies were made to determine effects of radioactive effluents from the Hanford reactors upon the aquatic biota of the Columbia River and to evaluate related hazards. Data from studies completed between September, 1945, and December, 1955 are presented and interpreted. All forms of life were many times more radioactive than the water they inhabited. Some radioisotopes were much more readily accumulated than others in living organisms. Differences in the concentration of certain radioisotopes by various species of organisms and kinds of body tissue are described; and geographical, seasonal and annual fluctuations in the concentration of radioisotopes in organisms are discussed.
Date: November 7, 1956
Creator: Davis, J. J.; Watson, D. G. & Palmiter, C.C.
Partner: UNT Libraries Government Documents Department
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National Security Commission on Artificial Intelligence: Interim Report, November 2019

Description: Report presenting the National Security Commission on Artificial Intelligence's initial (NSCAI)'s preliminary assessment of artificial intelligence (AI). It discusses NSCAI's definition of AI, the challenges and context around it, where the U.S. Government can apply it, considerations on ethical and trustworhy AI, and associated technologies.
Date: November 2019
Creator: National Security Commission on Artificial Intelligence (U.S.)
Partner: UNT Libraries Government Documents Department
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Final Report on Swell Detection by Pusher Method

Description: Experiments wee performed to evaluate the feasibility of detecting swelled slug elements in Hanford reactors by measuring the force necessary to push the slug column in its tube. These experiments are described. The results indicate the method presents no unsolvable problems.
Date: November 11, 1944
Creator: Shank, W. Bradford & Frankel, W.
Partner: UNT Libraries Government Documents Department
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Temperatures on the Surface of a Slug Jacket

Description: Prior to operating a chain reacting, graphite moderated, water cooled uranium pile at Hanford, the corrosive action of water on uranium was studied. It was necessary to enclose the uranium cylinders in Al jackets. Preliminary data were available which indicated Al jacket corrosion might be influenced by the water temperature. Therefore, in order to specify safe operating conditions, it was desirable to know the temperature at any position on the Al jacket of a slug in the tube. Because of the experimental difficulties encountered in the measurement of the correct surface temperature, the problem has been attacked primarily from a mathematical standpoint. Mathematical formulae have been developed for most of the proposed Hanford designs. The purpose of this report was to evaluate and summarize the theoretical and experimental information for calculation of Al jackets surface temperatures for the design now installed at Hanford. Also, the summarized results were to be put into a form suitable for use in routine calculations. As a result of this survey, the Al surface temperature for the Hanford tube and slug design may be calculated with 15 degrees C by employing routine methods and certain simple factors and equations contained in this report. The factors have been assembled from mathematical analyses but agree closely with the existing experimental data available. The equations are of the usual type used in hear transfer calculations. Until adequate experimental data are available, it is recommended that the factors and formulae presented be employed in the calculation of the the jacket surface temperatures. Experimental work is need to substantiate the formulae and factors obtained. Also, additional work is needed to determine the surface temperatures necessary to cause early failure of the slug jacket by corrosion, erosion, or cavitation.
Date: November 1, 1944
Creator: Monet, M.
Partner: UNT Libraries Government Documents Department
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Slug Jacket Temperatures

Description: Abstract. A method for calculating jacket temperatures in a region of varying heat transfer coefficients is given Some applications are made for temperatures above a supporting rib.
Date: November 8, 1944
Creator: Schlegel, Richard, 1913-
Partner: UNT Libraries Government Documents Department
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Thermal Transfer to an Annular Water Stream in the Neighborhood of a Rib

Description: Abstract. Steady-state temperatures were measured in an electrically heated brass cylinder which was water cooled in a four-ribbed Al tube. Thermal transfer coefficients h were calculated from the measured temperatures. Curves of h values are presented for the regions of high and low ribs. the h curve is found to show a much sharper break in the region of high rib than in a low rib region. There is some evidence that h decreases linearly with annular thickness in the range considered. The low rib is found to exert a much greater effect than the high rib in decreasing the h value at points distant from the rib.
Date: November 10, 1944
Creator: Kratz, H. R.; Schlegel, R. & Christ, Carl F.
Partner: UNT Libraries Government Documents Department
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A Sensitive Particle Ionization Chamber for Neutron Detection

Description: Abstract. A particle ionization chamber of sensitivity sufficient to detect a source of one neutron per second has been used to measure the neutron yield from a thick target of sulfur upon bombardment with polonium alpha particles. The high-geometry boron trifluoride chamber used had an efficiency of 1.9 percent for fission neutrons. The neutron yield from a thick target of sulfur was measured by this instrument and found to be .0035 +- .0013 neutrons per million incident polonium alpha particles.
Date: November 21, 1944
Creator: Sturm, William J. & Dabbs, John
Partner: UNT Libraries Government Documents Department
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Progress Report : Low Geometry Alpha Particle Ionization Chambers

Description: ABSTRACT. When solutions of high specific alpha activity are to be assayed for product, it is often difficult to obtain reproducible results by diluting the solution sufficiently to remove a small volume from which a sample can be prepared and counted at 52% geometry. In order to assay such a solution, most reproducible results have been obtained with minimum effort in sample preparation by making use of low geometry chambers. Two types of low geometry chambers are described: 1) The air-screen type which reduces the geometry simply by placing screens of various transparencies above the sample; and 2) The vacuum low geometry chamber which accomplishes geometry reduction by increasing the distance between sample and collecting electrode thus decreasing the solid angle subtended by the sample and aperture through which the particles pass into the ionization chamber. This type chamber was developed concurrently by this group and the instrument group of Chemistry Section C-I at the Metallurgical Laboratory. Because the geometry of the air-screen type chamber is quite critical to sample spreading and be- cause 12 mm sample plates are required, it has found very little use. On the other hand, the vacuum chamber, because it is noncritical to sample spreading and especially noncritical to sample thickness, has found widespread use in product chemistry studies and high alpha activity experiments. Photographs and drawings are included.
Date: November 8, 1944
Creator: Borokowski, C. J.; East, J. K. & Flatau, C.
Partner: UNT Libraries Government Documents Department
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