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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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Criminology Collection Evaluation Report

Description: This report summarizes an evaluation of the UNT Libraries' Criminology collection to determine if the collection is adequately serving patron needs. It was determined that the collection was currently meeting patrons' needs, and some recommendations for future collection maintenance were included.
Date: November 15, 2021
Creator: Harker, Karen
Partner: UNT Libraries
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Studio Arts Collection Evaluation Report

Description: This report summarizes an evaluation of the UNT Libraries' Studio Arts collection to determine if the collection is adequately serving patron needs. It was determined that the collection was currently meeting patrons' needs, and some recommendations for future collection maintenance were included.
Date: November 15, 2021
Creator: Harker, Karen
Partner: UNT Libraries
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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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A Report: Survey on Art Museum/School Collaborations

Description: The second part of a report for the National Center for Art Museum/School collaboration that includes a summary.
Date: November 1997
Creator: National Center for Art Museum/School Collaboration
Partner: UNT Libraries Special Collections
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The Resonance Absorption Spectrum of Uranium

Description: A model for the capture spectrum of uranium is introduced in which levels occur at 7, 30, 30+D, 30+2D, ..., ev. Gamma ray and neutron widths are derived from the experimental data for values of D between 10 and 25 ev. The constants of the 7 volt level prove to be independent of D. Extrapolation, using the one level formula, gives a capture cross section at (1/40) ev of 4.9 x 10(24) cm2; this number is, however, quite sensitive to the value taken for the resonance activation. Both neutron and gamma ray widths for the higher levels are approximately proportional to D.
Date: November 24, 1943
Creator: Dancoff, Sidney M., 1913-1951
Partner: UNT Libraries Government Documents Department
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Diffusion of Xenon in Columbium

Description: The diffusion coefficient was calculated for the diffusion of Xe through Nb and found to be 0.064 exp (-18,600/RT).
Date: November 20, 1959
Creator: Gregory, D. P. (Derek P.) & Leavenworth, H. W. (Howard W.)
Partner: UNT Libraries Government Documents Department
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The Determination of Thorium in Uranium-Thorium Alloys, Using Cupferron

Description: Technical report describing that the use of controlled amounts of carbonate, acting both as complexing agent buffer led to a fairly satisfactory procedure for the determination of Th in Th-U alloys, using cupferron. The alloy, dissolved in NHO2, in the presence of HF, is treated with H2SO4 and the mixture is evaporated in SO2 fumes. The solution is diluted and (NH4)2CO2 is added. Th is precipitated from this solution with cupferron. The precipitate is weighed as ThO2 after ignition. An accuracy of 6% was obtained. A method was developed specifically for the determination of Th in U-Th alloys containing 1 to 10% Th. An ion exchange resin in column is used to separate Th from U, with NH2OH-HCl as complexing agent. The Th is then precipitated, ignited, and weighed in the conventional manner.
Date: November 23, 1945
Creator: Eckert, A. C. & Bane, R. W.
Partner: UNT Libraries Government Documents Department
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The Rapid Determination of Nitric Acid and Thorium in Thorium Nitrate Solutions

Description: Abstract. The physico-chemical methods of determining nitric acid and thorium nitrate in solutions containing these two materials were investigated. Conductimetric titration with sodium hydroxide can be used to determine nitric acid accurately. the titration of thorium nitrate requires a separate standardization of the base however, since a basic salt is precipitated rather the normal hydroxide. The titration of thorium is reproductible however, so and empirical standardization can be used. The measurement of the specific gravity and refractivity of the solutions provides a method of determining the concentrations in terms of these two variable. Equations for the concentrations in terms of specific gravity and refractively are given, both in pure solutions and in those saturated with methyl isobutyl ketone.
Date: November 27, 1945
Creator: Newton, A. S.; Powell, J. (James), 1932- & Figard, P
Partner: UNT Libraries Government Documents Department
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Extraction of Uranyl Nitrate and Thorium Nitrate by Organic Solvents

Description: Abstract. The separation of uranyl nitrate from aqueous solutions of 0.635 M thorium nitrate, 3 M nitric acid and 3 M calcium nitrate by extraction with organic solvents has been investigated. Solvents which gave good separations were 2-tthyl hexyl acetate, ethyl benzoate, n-butyl either and beta-beta- dichloroethyl ether. In general, higher esters, ethers and alcohols are better for separating uranium from thorium that the lower homologues. Several solvents were tested at lower nitric acid concentrations. Dibutyl cellosolve gave a very good separation when the solution was 0.1 M nitric acid. Of the solvent mixtures studied that of equal parts of n-butyl ether and dibutyl cellosolve gave a good separation.
Date: November 5, 1945
Creator: Johnson, O. & Newton, A. S.
Partner: UNT Libraries Government Documents Department
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The Effects of Neutron Bombardment on the Electrical Resistance of Aluminum, Beryllium and Tuballoy (Uranium)

Description: Abstract. Wigner effects on aluminum, beryllium, and tuballoy have been studied by the electrical resistance method. Samples were exposed during an interval which would have produced an increase of approximately 22% in resistance of AGOT-K graphite. The resistance of tuballoy increased approximately 1%. It is shown that the increase can be accounted for by the amount of fission product impurity formed during the exposure. Neither aluminum nor beryllium showed any change. In the case of Be, the Wigner effect may be obscured, to some extent, by the approximately .2 - .3 atom % of impurity present in the samples. Based on the increase occurring in ADOT-K graphite, a change of approximately .2 - .5 x10-6 ohm-om might be expected in the case of Be. The accuracy of the method was sufficiently great to detect a change of this magnitude. Other experiments with Be will be undertaken when purer samples are available. Meanwhile, some samples of the present type ae being subjected to further irradiation.
Date: November 2, 1944
Creator: Royal, J.
Partner: UNT Libraries Government Documents Department
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Metallurgical Laboratory, Chemical Research - Radiation Chemistry, Report for the Month Ending October 31, 1944

Description: Technical report with short reports on (1) Effect of radiation on organic compounds; (2) Effect of radiation on separation processes; (3) Effect of radiation on water and aqueous systems; and (4) Effect of neutrons on graphite.
Date: November 14, 1944
Creator: Hogness, T. R. (Thorfin Rusten), 1894- & Burton, Milton, 1902-
Partner: UNT Libraries Government Documents Department
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Effect of Radiation on Chromate in Water. III. Inhibition Experiments in the CP-3 Pile

Description: Abstract. The effect of various inhibitors on the production of CrIII in W waters containing chromatic has been studies at a variety of pH's in the CP-3 pile. The addition of 2 ppm NaClO3 appears to have little effect a a pH of 5.3, but 2 ppm NaClO3 cr 0.15 ppm of Cl2 (in the form of NaOCl) somewhat decreases the amount of chromatic reduced at a pH of 7.1. The inhibition is not great enough, however, to reduce the amount of CrIII formed to the maximum concentration permissible at W (0.02 ppm). The addition of 3 ppm (NH4)2S2O3 as an inhibiter will permit W water to be used a a Ph of 7.0, but not at a pH of 6.5 as far as chromate reduction is concerned. The concentration of CrIII would be 0.01 ppm and 0.05 ppm, respectively, after one passage through the pile. Previous conclusion as to the effects of temperature, pH, intensity and the addition of ammonium persulfate, which had been reached from experiments with simulation W water, have been checked by studies with solutions made from water chipped directly from Hanford. All of the effects noted were found to be similar to those already reported, but the actual chromate reduction appears to be slightly less in the real W water sample studied than in simulated W water.
Date: November 2, 1944
Creator: Bowman, M. G.; Burton, Milton, 1902-; Davis, S. G., 1907-; Ghormley, J. A. & Gordon, S.
Partner: UNT Libraries Government Documents Department
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