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A Study of the Kinetic and Mechanical Properties of a Stabilized Beta Phase Plutonium Alloy

Description: The elements Sn, Mg, Ti, Zr, Hf, Si, Cd, and U were alloyed with plutonium to determine their effect on stabilization of the beta phase. Zirconium was found to be the ' most effective. Kinetic studies were conducted on Pu-Zr alloys having 0.24, 0.65, and 1.7 at.% Zr contents. The beta to alpha transformation in the Pu-Zr alloys was somewhat similar to that in unalloyed plutonium. The main difference being that time, temperature, transformation curves of the alloys were shifted to the right as t… more
Date: January 1, 1962
Creator: Taylor, J. M.
Partner: UNT Libraries Government Documents Department
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Theory of ordering transformations in metals and minerals

Description: This dissertation presents an investigation of ordering in FCC based systems using the pair potential approximation in the ground state and mean field limits. The theoretical approach is used to explain the occurrence of observed equilibrium phases and characteristics of thermodynamic instabilities, in particular, spinodal ordering and decomposition. It is shown that the stability of non-integer domain sizes in long period superstructures such as Al{sub 3}Ti and Ag{sub 3}Mg may result from the … more
Date: July 1, 1991
Creator: Lindsey, Timothy Francis
Partner: UNT Libraries Government Documents Department
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Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating

Description: ent temperature variation in a thermally orthotropic plate which is subjected to an arbitrary heating rate distribution along one face with all other surfaces being insulated. Dimensionless temperature histories and distributions determined from this solution are presented for the special, but representative, case of a linearly varying heating rate distribution on plates with varying degrees of thermal orthotropy. These results establish quantitatively the value of a material with high planar a… more
Date: June 1, 1961
Creator: Hornbaker, David Ross
Partner: UNT Libraries Government Documents Department
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A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops

Description: Mathematical models of the time-dependent behavior of two-phase natural- circulation loops were used to predict the operation and to explain the unusual instability sometimes observed. The initial results obtained for a loop similar to the Univ. of Minnesota loop were used to formulate a more complex and accurate model, and the predicted transient behavior was in close agreement with the experimental results from the Minnesota loop. For a 300psia, high-pressure loop, unstable oscillatory behavi… more
Date: June 1, 1961
Creator: Garlid, K.; Amundson, N. R. & Isbin, H. S.
Partner: UNT Libraries Government Documents Department
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Americium and plutonium in water, biota, and sediment from the central Oregon coast

Description: Plutonium-239, 240 and americium-241 were measured in the mussel Mytilus californianus from the region of Coos Bay, OR. The flesh of this species has a plutonium concentration of about 90 fCi/kg, and an Am-241/Pu-239, 240 ratio that is high relative to mixed fallout, ranging between two and three. Transuranic concentrations in sediment, unfiltered water, and filterable particulates were also measured; none of these materials has an Am/Pu ratio as greatly elevated as the mussels, and there is no… more
Date: June 1, 1982
Creator: Nielsen, R. D.
Partner: UNT Libraries Government Documents Department
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The Specific Heat of Dysprosium Metal Between 0.4 and 4 K

Description: Submitted to Illinois Inst. of Tech., Chicago. A He/sup 3/ cryostat was built to measure the specific heat of rare earth metals which have a component, at low temperatures, attributable to the electrons in the incomplete 4f shell. The specific heat of dysprosium from 0.4 to 4.2 deg K was measured. Pertinent theories about specific heats are outlined. The apparatus included the cryostat, vacuum and He/sup 3/ systems, calorimeter, carbon thermometer, heater, and magnetic thermometer. The experime… more
Date: August 1, 1962
Creator: Guenther, R. A.
Partner: UNT Libraries Government Documents Department
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Response of Shortgrass Plains Vegetation to Chronic and Seasonally Administered Gamma Radiation

Description: In order to determine the effect of radiation on the structure of native shortgrass plains vegetation, an 8750 Ci 137Cs source was installed on the Central Plains Experimental Range near Nunn, Colorado; The experimental area was divided into 6 treatment sectors, a control, 2 sectors for chronic exposure (irradiation initiated April 1969 and continuing as of August 1971), and one each for spring, summer and late fall seasonal semi-acute (30 day), exposures which were administered during April, J… more
Date: August 1, 1971
Creator: Fraley, L. Jr.
Partner: UNT Libraries Government Documents Department
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Dynamic Simulation of Multi-Pass Pressurized Water Nuclear Power Plants by Analog Computer Techniques

Description: A kinetic model of the primary loop of a multi-pass pressurized water reactor power plant is developed to evaluate, by analog computer techniques, the transient response characteristics under conditions of steam generator load and reactor control rod perturbations. Using the 2-pass 28 Mw(t) SM-2 reactor as a typical plant, transient behavior patterns are illustrated and examined for a variety of load inputs, variations in plant constants, and analog model simplifications. (auth)
Date: June 1, 1961
Creator: Brondel, J. O.
Partner: UNT Libraries Government Documents Department
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Solid State Neutron Detectors

Description: No Description Available.
Date: May 1, 1961
Creator: Murphy, J. F.
Partner: UNT Libraries Government Documents Department
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Low temperature heat capacity of lutetium and lutetium hydrogen alloys

Description: The heat capacity of high purity electrotransport refined lutetium was measured between 1 and 20/sup 0/K. Results for theta/sub D/ were in excellent agreement with theta values determined from elastic constant measurements. The heat capacity of a series of lutetium-hydrogen solid solution alloys was determined and results showed an increase in ..gamma.. from 8.2 to about 11.3 mJ/g-atom-K/sup 2/ for hydrogen content increasing from zero to about one atomic percent. Above one percent hydrogen ..g… more
Date: October 1, 1977
Creator: Thome, D. K.
Partner: UNT Libraries Government Documents Department
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Polariton effects in naphthalene crystals

Description: The experimental verification of the two-step nature of energy dissipation of photon energy by a crystal is the subject of this dissertation. The ..cap alpha..(O,O) Davydov component of the lowest energy singlet transition in pure strain-free napthalene single crystals is shown to exhibit an increase in absorption with increasing temperature, due to an increase in polariton damping via polariton-phonon scattering processes. (GHT)
Date: October 1, 1977
Creator: Robinette, S. L.
Partner: UNT Libraries Government Documents Department
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Ejection of Large Fragments in High-Energy Nuclear Reactions

Description: Several features of the production of Na/sup 24/ and Mg/sup 28/ fragments produced in the interaction of protons and He ions with Cu, Ag, Au, and U were investigated. Formation cross sections were determined for He ions of different energies between 320 and 880 Mev and for protons of 700 Mev. Thick- target recoil experiments were performed at bombarding energies of 0.7 and 3 Bev for protons, and 880 Mev for He ions. Also given are some recoil measurements of Na/sup 24/ from Al. Analysis of data… more
Date: September 1, 1961
Creator: Crespo, V. P.
Partner: UNT Libraries Government Documents Department
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