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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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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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Synthesis and characterization of an N-(2-hydroxyethyl)-ethylenediaminetriacetic acid resin

Description: A chelating ion-exchange resin with N-(2-hydroxyethyl)ethylene-diaminetriacetic acid (HEDTA) used as the ligand chemically bonded to XAD-4 by an ester linkage, HEDTA-4, was synthesized. It is stable under normal experimental conditions with the liquid chromatograph. The structure of the resin was confirmed by an infrared spectrum, and by potentiometric titrations. The capacity of the resin was also obtained by potentiometric titration and by a nitrogen analysis. The resin was used to pack a col… more
Date: October 1, 1977
Creator: Lai, Y. F.
Partner: UNT Libraries Government Documents Department
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Electron microscopy of hydrocarbon production in parthenium argentatum (guayule)

Description: The electron microscope was used to study the biological processes involved in hydrocarbon production. The little desert shrub Guayule (Parthenium argentatum) was selected for study. This shrub can produce hydrocarbons (rubber) in concentrations up to 1/4 of its dry weight. It grows on semi-arid land and has been extensively studied. The potential of Guayule is described in detail. Results of an investigation into the morphology of Guayule at the electron microscope level are given. Experiments… more
Date: November 1, 1977
Creator: Bauer, T.E.
Partner: UNT Libraries Government Documents Department
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Stress induced reorientation of vanadium hydride

Description: The critical stress for the reorientation of vanadium hydride was determined for the temperature range 180/sup 0/ to 280/sup 0/K using flat tensile samples containing 50 to 500 ppM hydrogen by weight. The critical stress was observed to vary from a half to a third of the macroscopic yield stress of pure vanadium over the temperature range. The vanadium hydride could not be stress induced to precipitate above its stress-free precipitation temperature by uniaxial tensile stresses or triaxial tens… more
Date: October 1, 1977
Creator: Beardsley, M. B.
Partner: UNT Libraries Government Documents Department
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Electromigration of hydrogen and deuterium in vanadium, niobium, and tantalum

Description: The electric mobility and effective valence of hydrogen and deuterium in vanadium, niobium, tantalum and three niobium-tantalum alloys were measured. A resistance technique was used to directly determine the electric mobility of hydrogen and deuterium at 30/sup 0/C while a steady-state method was used to measure the effective valence. The use of mass spectrographic techniques on a single specimen which contained both hydrogen and deuterium greatly increased the precision with which the isotope … more
Date: October 1, 1977
Creator: Jensen, C. L.
Partner: UNT Libraries Government Documents Department
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Use of a semiconductor laser in infrared spectroscopy

Description: A semiconductor laser has certain properties which makes its use desirable as a continuous monitor of atmospheric pollutants. Its energy output is concentrated in widely separated energy modes of very narrow bandwidths (less than 10/sup -5/ cm/sup -1/) which can be centered on one infrared absorption line of one gas. This makes the laser quite selective. The energy in each mode is typically greater than 200 ..mu.. watts, and, because of the laser's small size, its light energy can be colli… more
Date: December 1, 1977
Creator: Morris, R. N.
Partner: UNT Libraries Government Documents Department
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Inductively coupled plasma--atomic emission spectrometry: trace elements in oil matrices

Description: The simultaneous determination of up to 20 trace elements in various oil matrices by inductively coupled plasma-atomic emission spectrometry is reported. The oil matrices investigated were lubricating oils (for wear metals), fuel oil, centrifuged coal liquefaction product, crude soybean oil, and commercial edible oils. The samples were diluted with appropriate organic solvents and injected into the plasma as an aerosol generated by a pneumatic nebulization technique. Detection limits of the 28 … more
Date: December 1, 1977
Creator: Peterson, C. A.
Partner: UNT Libraries Government Documents Department
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Analytical applications of resins containing amide and polyamine functional groups

Description: A dibutyl amide resin is used for the separation of uranium(VI), thorium(IV), and zirconium(IV) from each other and several other metal ions. Uranium(VI) and thorium(IV) are determined in the presence of large excesses of foreign metal ions and anions. A practical application of the amide resin is studied by determining uranium in low grade uranium ores. The amide resin is also used for the selective concentration of gold(III) from sea water.
Date: December 1, 1977
Creator: Orf, G. M.
Partner: UNT Libraries Government Documents Department
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Dislocation morphology in deformed and irradiated niobium. [Neutron irradiation]

Description: Niobium foils of moderate purity were examined for the morphology of dislocations or defect clusters in the deformed or neutron-irradiated state by transmission electron microscopy. New evidence has been found for the dissociation of screw dislocations into partials on the (211) slip plane according to the Crussard mechanism: (a/2) (111) ..-->.. (a/3) (111) + (a/6) (111).
Date: June 1, 1977
Creator: Chang, C. P.
Partner: UNT Libraries Government Documents Department
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Lanthanide extraction with 2,5-dimethyl-2-hydroxyhexanoic acid

Description: This research is concerned with the solvent extraction into chloroform of the lanthanides, using 2,5-dimethyl-2-hydroxyhexanoic acid (DMHHA). This acid is the first ..cap alpha..-hydroxy aliphatic acid to be studied as an extracting agent for the lanthanides. The chloroform-water DMHHA partition constant was determined to be 1.0 (at 0.1 M ionic strength and 25/sup 0/C). The acid dimerizes in chloroform with a constant of 56. The light lanthanides can be extracted into chloroform by forming comp… more
Date: December 1, 1977
Creator: Miller, J. H.
Partner: UNT Libraries Government Documents Department
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Investigation of high energy runaway electron confinement in the Oak Ridge tokamak

Description: High energy runaway electrons in the Oak Ridge tokamak ORMAK have been investigated through measurement of the bremsstrahlung produced when these electrons leave the discharge and strike the limiting aperture of the torus. The experimental results have been interpreted in terms of a classical single-particle model appropriate for collisionless particles in a tokamak, and it has been found that most of the confinement properties of high energy runaways in ORMAK can be understood on this basis. A… more
Date: November 1, 1977
Creator: Zweben, S. J.
Partner: UNT Libraries Government Documents Department
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Heated uranium tetrafluoride target system to release non-rare gas fission products for the TRISTAN isotope separator. [As replacement for uranyl stearate]

Description: Off-line experiments indicated that fluorides of As, Se, Br, Kr, Zr, Nb, Mo, Tc, Ru, Sb, Te, I and Xe could be volatilized, but except for Br, Kr, I and Xe, none of these elements were observed after mass separation in the on-line experiments. The results of the on-line experiments indicated a very low level of hydride contamination at ambient temperature and consequently, uranium tetrafluoride replaced uranyl stearate as the primary gaseous fission product target. Possible reasons for the fail… more
Date: October 1, 1977
Creator: Gill, R. L.
Partner: UNT Libraries Government Documents Department
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Photoexcitation in Superconductors

Description: Dissertation discussing the results of experiments to study the behavior of superconductors under light illumination.
Date: June 1976
Creator: Schuller, Ivan
Partner: UNT Libraries Government Documents Department
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