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Rates of Convergence in Numerical Solution of the Diffusion Equation

Description: A basic technique in the design of a nuclear power reactor is to prescribe the dimensions and composition of a simplified model and to calculate the corresponding neutron flux and power distributions. Comparison of calculations for different models and of particular calculations to experimental results guides the physicist to a reasonable prescription. Until recently, the usual model had spherical or cylindrical symmetry. We have found it feasible to extend the methods to include a class of rea… more
Date: 1954
Creator: Stark, R. H.
Partner: UNT Libraries Government Documents Department
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Effects of Ultraviolet Radiation on Chloroplast Reactions and Plant Metabolism

Description: This technical report represents a brief survey of work by this project on the effects of ultraviolet radiation (UV) on certain of the photochemical and metabolic properties of rhubarb chard and sugar beet (Beta vulgaris). These plants were selected for this work because for some years they have been used as sources of chloroplasts for Hill reaction studies in this laboratory. Some of this work has appeared as a brief paper.
Date: June 15, 1955
Creator: Anderson, Donald R.; Spikes, John D. & Mayne, Berger C.
Partner: UNT Libraries Government Documents Department
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The Effect of Crystallite Size on the Bulk Density and Strength Properties of Uranium Dioxide Specimens

Description: Fused uranium dioxide was separated into fractions of varying particle size by air separation. Specimens of the nominal size of 1/8 by 1/4 by 1½ in. were formed by hydrostatic pressing, firing, and lapping. Specimens prepared from the 0 to 5 μ fraction were the strongest and most dense. The room-temperature density was about 92% of theoretical and the room-temperature flexural strength was about 12,000 1b. per sq. in. When tested at 1000°C., the strength was about 18,000 1b. per sq. in. The fle… more
Date: June 1, 1955
Creator: Burdick, Milton D. & Parker, H. S.
Partner: UNT Libraries Government Documents Department
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Intermediary Metabolism of the Photosynthetic Bacteria. Final Report

Description: The primary purpose of these researches was to clarify the various functions of organic substrates in bacterial photosynthesis. The following aspects were investigated; (1) metabolic pathways under photosynthetic and oxidative conditions, (2) energy transfers occurring during the metabolism in cell free extracts, and (3) the relationship between photosynthetic rate and light intensity for selected organic substrates. The results of these investigations were summarized in a paper entitled "The A… more
Date: November 1, 1955
Creator: Siegel, Jack M.
Partner: UNT Libraries Government Documents Department
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Progress Report No. 37 for the Period June 1, 1955 through August 31, 1955

Description: This is the thirty-seventh progress report of the Laboratory for Nuclear Science at the Massachusetts Institute of Technology. Progress during the period of June 1, 1955 through August 31, 1955 is reported on: (1) Chemistry of the fission elements group, (2) Nuclear chemistry (inorganic) group, (3) Nuclear chemistry (organic) group, (4) Cosmic ray group, (5) Elementary particle scattering group, (6) neutron physics group, (7) ONR generator group, (8) Radioactivity group, (9) Cyclotron group, (1… more
Date: August 31, 1955
Creator: {{{name}}}
Partner: UNT Libraries Government Documents Department
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The Equation of State of Water on the Thomas-Fermi Model

Description: Two methods are described for extending the Thomas-Fermi model of a compressed atom to molecules or mixtures of the type Z Zn. The methods are applied to H2O at zero temperature to determine pressure and internal energy as functions of the density, the position of the protons relative to the oxygen nucleus, and the electrostatic potential distribution within the molecule.
Date: October 24, 1955
Creator: Latter, A. & Latter, R.
Partner: UNT Libraries Government Documents Department
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Photoelectric K and l Shell Absorption Coefficients for Highly Ionized Atoms

Description: This technical report describes a simple way to calculate numerical values of K and l shell photoelectric absorption coefficients (averaged over subshells) for highly ionized atoms.
Date: November 1, 1955
Creator: Moszkowski, S. A. & Meyerott, Roland Edward
Partner: UNT Libraries Government Documents Department
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A Cloud Chamber Study of the Secondary Particles from Locally Produced Penetrating Showers

Description: The present experiment was undertaken as an attempt to throw more light on the decay processes that had been observed prior to the summer of 1952, as well as to investigate any new decay processes that might manifest themselves. The source of high energy primary particles was to be the cosmic ray beam, so a detector of locally produced high energy penetration showers was used. In order to be able to detect effectively low energy photons and low energy secondaries from particles reaching the end… more
Date: September 1955
Creator: Harmon, Norman Frederick
Partner: UNT Libraries Government Documents Department
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Measurement of Respiratory C14O2 Activities

Description: We describe in this technical report a reasonably simple, easily constructed, system that allows the collection of time-course information regarding respiratory C14O2 with little special effort on the part of the investigator. The method described is centered around a small metabolism cage for the animal and a novel technique for counting C14O2. In essence, an air steam containing C14O2 is brought part the window of a think end window G.M. tube contained in a lead shield. activity detected by t… more
Date: 1955
Creator: Bruggen, J. T. van, 1913-1989 & Hutchens, Tyra T.
Partner: UNT Libraries Government Documents Department
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Occurrence of Technetium in Nature : Final Report for the Period November 1, 1954 to August 31, 1955

Description: Twelve neutron activation analyses for naturally occurring technetium-98 were performed. Positive results were obtained in ten cases. Precautions were taken to avoid interference by molybdenum and technetium-99. the cross section for the reaction [formula] as found to be equal to 4 +- 2 mb for the neutron spectrum of the vertical thimbles of the Argonne CP-5 reactor. The chemical state of molybdenum (VI) in basic solution was studied by an anion-exchange technique. Evidence was obtained for the… more
Date: September 1, 1955
Creator: Anders, Edward, 1926-
Partner: UNT Libraries Government Documents Department
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Underground Movement of Radioactive Wastes

Description: The theory and preliminary laboratory investigations presented in this technical report were intended to examine the general feasibility of injection disposal of radioactive wastes and to establish an understanding of the phenomena governing the travel of trace chemicals through natural porous media. Detailed studies of fluid velocity variations resulting from density differences between the injected and displaced liquids have been made. the ion exchange studies have been limited to strontium a… more
Date: August 1, 1955
Creator: Kaufman, Warren J., 1922-; Orcutt, Richard G., 1924- & Klein, Gerhard, 1918-1987
Partner: UNT Libraries Government Documents Department
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Media for Air Cleaning and Air-Assay Purposes : Final Summary Report for Period Ending December 31, 1954

Description: Work was completed on the high-temperature, high efficiency air filter. Technical assistance was given at a large-scale, privately financed run of an all-glass medium. Full-size filers have been produced in quantity and are offered by manufacturers; it is considered that commercial manufacture has been established. A survey was made of air sampling practices at 37 laboratories. Analysis of the survey results indicated that 22 different kinds of air-sampling filer media were in use among the lab… more
Date: October 3, 1955
Partner: UNT Libraries Government Documents Department
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An Investigation of Scaling of Zirconium at Elevated Temperatures : Quarterly Status Report No. 10; Sept. 2, 1955 to Dec. 2, 1955

Description: As previously reported, zirconium undergoes large dimensional increases after scaling in air in a critical temperature range, 700 degree-1050 degree C. This finding was observed with specimens of a constant thickness (0;062 in.) To study the thickness effect, a number of specimens ranging in thickness from 0.020 to 0.200 in. were scaled in air at a temperature (900 degree C) where the growth is a maximum for a given time. Both cold rolled iodine sheet and forged iodide bar stock were used. to d… more
Date: December 8, 1955
Creator: Barrett, Charles A.; Evans, E. B. & Baldwin, W. M., Jr.
Partner: UNT Libraries Government Documents Department
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Genetic Resistance to X-Irradiation in Mice

Description: A comparison was made of the effects of X-irradiation on mice of the high leucocyte (LCH) count strain and low leucocyte count strains. Among 30-day old mice, the LCH strain had a significantly lower mortality after irradiation, but in five-month old mice there was no difference between strains. Weight changes after irradiation do not differ between strains, in either age group. Leucocyte counts of both strains drop to the same level several days after irradiation. Mortality, changes in leucocy… more
Date: 1955
Creator: Swanson, Harold Dueker; Leone, Charles A. & Weir, J. A.
Partner: UNT Libraries Government Documents Department
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Decay Scheme of In107

Description: The gamma radiations of In107 have been investigated with a scintillation spectrometer . The In107 was produced in a cyclotron by a (d,n) reaction on electromagnetically enriched Cd106. Beta-gamma and y-y coincidence experiments showed in addition to the annihilation radiation, only one y ray of 0.22 Mev associated with the 2.2 Mev positron.
Date: 1955
Creator: Cassatt, Wayne A., 1925- & Meinke, W. Wayne
Partner: UNT Libraries Government Documents Department
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Carcinogenesis by Radioactive Substances

Description: Knowledge of the potential dangers of exposure to radioactive substances and the institution of proper safety precautions have helped to reduce accidental exposures to radioactive substances. In the following technical report we shall review briefly carcinogenesis in man by naturally occurring and artificially produced radioactive substances, the lung cancer problem in miners, the development of bone tumors in luminous dial painters and in patients treated with radium-containing nostrums, and t… more
Date: 1955
Creator: Furth, Jacob & Tullis, John L.
Partner: UNT Libraries Government Documents Department
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The Electronic Energy Levels and the Mass Spectrum of Methane

Description: Recent instrumental developments and theoretical speculation have indicated a need for more information concerning the excited electronic states of polyatomic molecules and ions in the elucidation of mass spectra. A theoretical description of these states is necessary for the proper interpretation of existing data and in laying a firm basis for the planning of future experiments. For the above reasons the energies of a number of the excited electronic states of methane have been calculated in a… more
Date: July 1954
Creator: Krauss, Morris; Wahrhaftig, Austin L. & Eyring, Henry, 1901-1981
Partner: UNT Libraries Government Documents Department
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Aerosol Collection by Wetted Fiberglass Media

Description: A wet collection system for aerosols has been developed using fibrous media. Tests show the performance to be in accord with recently developed theory of collection by fibrous media. The effects of varying aerosol particle size, particle density, and gas velocity have indicated that inertial impaction is the primary collection mechanism. Three-year operating experience on several full scale plant installations shows reliable performance.
Date: April 28, 1954
Creator: Leary, Joseph A.; Clark, Robert A.; Hammond, R. Philip & Leopold, Charles S.
Partner: UNT Libraries Government Documents Department
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An Investigation of Scaling of Zirconium at Elevated Temperatures Quarterly Status Report no. 9.June 2, 1955 to Sept. 2, 1955

Description: To obtain a better understanding of the mechanism involved in scaling behavior of zirconium, kinetic studies were made of the weight pickup in air after the following pretreatments; (1) exposure to oxygen or nitrogen, (2) exposure to air, oxygen or nitrogen and removal of the resulting surface compounds.
Date: September 6, 1955
Creator: Green, H. M.; Tuchschmid, Heinrich Eugen, 1922- & Baldwin, W. M., Jr.
Partner: UNT Libraries Government Documents Department
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Photocathode and Reflector Effects n Relative Pulse Height Measurements

Description: The first highly productive phase in the development of organic scintillation detectors found physicists exploring the excitation and light emission properties of easily available organic chemicals. The second phase of this work which is now in progress can be characterized by the active participation of organic chemists in synthesizing new compounds for sturdy and setting standards of purity leading to the recognition by some chemical manufactures of a "scintillation grade".
Date: August 1954
Creator: Hayes, F. Newton (Francis Newton), 1924- & Rogers, Betty S
Partner: UNT Libraries Government Documents Department
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The Mass Spectrum of Methane and the Energy Levels of the Fragment Ions and Radicals

Description: A MO calculation of the electronic states of CH4, CH3, CH2, CH, and their respective ions provided the basis for the application of correlation rules to an analysis of the existing appearance potential data for methane. An interpretation of the methane mass spectrum has been proposed which is based on the high value of the heat of sublimation of carbon. It is shown that the excited electronic states of the molecule- and radical-ions are prominent in the decomposition reactions.
Date: July 1955
Creator: Krauss, Morris; Wahrhaftig, Austin L. & Eyring, Henry, 1901-1981
Partner: UNT Libraries Government Documents Department
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Precise Closed-Form Solutions of Some Mixed Boundary Value Problems of Plane Elasticity

Description: Precise solutions are given for the problem of the semi-infinite strip extending from x=0 to x=infinity, stress-free along the edges y= +-1, when the edge x=0 is subject (a) to a quadratic sheer displacement and zero normal stress, (b) to a cubic normal displacement and zero sheer stress. These are the two simplest (non-trivial) end problems of the semi-infinite strip, antisymmetric in y, that may be formulated. The corresponding symmetric problems (a) linear seer displacement and zero normal s… more
Date: 1954
Creator: Horvay, Gabriel, 1908- & Born, J. B.
Partner: UNT Libraries Government Documents Department
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Sealing Radioactive Specimens in Glass Ampoules

Description: In studying the effect of neutron irradiation on certain kinds of metal wire, specimen storage was found to present a serious problem, since the specimens oxidized rapidly once removed from the protective atmosphere of the irradiation capsule. After trying several methods of storage it was found that sealing the radioactive samples in individual evacuated glass ampoules was best from both the standpoint of sample protection and minimum spread of radioactive contamination. The sealing technique … more
Date: 1955
Creator: Reynolds, Myron B.
Partner: UNT Libraries Government Documents Department
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The Chlorine Trifluoride-Hydrogen Fluoride System. Some Vapor Pressure and Conductance Measurements

Description: The possible existence of a stable complex between chlorine trifluoride and hydrogen fluoride made further study of this system desirable. We have therefore investigated the vapor pressures and specific conductances of solutions of hydrogen fluoride in chlorine trifluoride.
Date: 1957
Creator: Rogers, Max T.; Speirs, John L. & Panish, Morton B.
Partner: UNT Libraries Government Documents Department
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