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The Sorption/Desorption Behavior of Uranium in Transport Studies Using Yucca Mountain Alluvium

Description: Yucca Mountain, Nevada is the proposed site of a geologic repository for the disposal of spent nuclear fuel and high-level radioactive waste in the United States. In the event repository engineered barriers fail, the saturated alluvium located south of Yucca Mountain is expected to serve as a natural barrier to the migration of radionuclides to the accessible environment. The purpose of this study is to improve the characterization of uranium retardation in the saturated zone at Yucca Mountain … more
Date: February 15, 2006
Creator: Scism, C. D.
Partner: UNT Libraries Government Documents Department
open access

The Relationships Among Self-Esteem, Marital Communication, and Marital Adjustment

Description: This investigation seeks to determine the correlations among the three factors of self-esteem, marital communication and marital adjustment to determine if these factors are evidenced similarly in the marital system, and to determine if their relationships are consistent among a wide range of marriages. In addition, several demographic variables are isolated in order to determine their influence on the three factors under investigation. Based on the findings of the study, it was concluded that … more
Date: February 1980
Creator: Carter, Warren Leslie
Partner: UNT Libraries
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Femtosecond Photoelectron Spectroscopy: A New Tool for the Study of Anion Dynamics

Description: A new experimental technique for the time-resolved study of anion reactions is presented. Using femtosecond laser pulses, which provide extremely fast ({approx} 100 fs) time resolution, in conjunction with photoelectron spectroscopy, which reveals differences between anion and neutral potential energy surfaces, a complex anion reaction can be followed from its inception through the formation of asymptotic products. Experimental data can be modeled quantitatively using established theoretical ap… more
Date: February 1, 1999
Creator: Greenblatt, B. J.
Partner: UNT Libraries Government Documents Department
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Zinc Metabolism of Young College Women on Self-Selected Diets

Description: The function of zinc in the nutrition of man has been studied by numerous investigators in an attempt to determine the needs of the body for this element. To date no deficiency disease has been produced by a zinc-deficient diet and cured by the addition of this element to the diet. The only criteria thus far presented to establish its essentialness in the dietary of man are the facts that zinc is retained by the body and that its presence is necessary for normal functioning of other nutrients. … more
Date: February 1953
Creator: Tribble, Helen Marie
Partner: UNT Libraries
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A Study of the Endocrine Glands and Their Implications for Education, with Special Emphasis on Industrial Arts

Description: This is a study of the endocrine glands and their influence on the physical characteristics and behavior patterns of adolescents. The purpose of this study is not to present new ideas about the effects of the endocrine glands upon man, but to gather and present the information and data already available and to show how these glands of internal secretion affect the individual in his ability to participate in an educational program, with special emphasis on industrial arts.
Date: February 1953
Creator: Cox, Lucius L.
Partner: UNT Libraries
open access

Internal friction in intrinsic and N-type germanium and silicon

Description: The high-temperature internal friction of germanium and silicon, intrinsic and highly n-type, was measured as a function of temperature, frequency, dislocation density, and dopant concentration. Two features found in the internal-friction spectrum were investigated. At moderate temperatures in both materials, when not too highly doped, there appears a peak, the features of which are independent of dislocation density, due to the acousto-electric effect. The high-temperature dislocation-dependen… more
Date: February 1, 1974
Creator: Gerk, Alvin Phillip
Partner: UNT Libraries Government Documents Department
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An Investigation into the Characteristics and Causes of Monthly and Yearly Price Fluctuations of Spot Cotton at New York, New York, During the Period, 1911-1953

Description: This study endeavors to give an insight into the causes and characteristics of price fluctuations of spot cotton at New York, N.Y., for the period 1911-1953, and to indicate whenever possible the factors which caused the price of cotton to rise or fall during selected periods.
Date: February 1954
Creator: Reynolds, Harry M.
Partner: UNT Libraries
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Nitration of Thiophene Analogs of DDT

Description: Since thiophene very often yields compounds that are analogous to benzene derivatives in general physiological properties, it was decided to attempt to prepare the nitro and amino derivatives of 1,1,1-trichloro-2,2-bis-(2-thienyl)-ethane (V) as well as the nitro and amino derivatives of 2,2,3-trichloro-1,1-bis-(2-thienyl)-butane (VI).
Date: February 1953
Creator: Buttram, Jack Rhea
Partner: UNT Libraries
open access

Collision-induced dissociation reactions and pulsed field ionization photoelectron

Description: This report summarized the four parts of the research study and describes the general conclusions. Individual chapters have been removed for separate processing. The chapter titles are: A study of the dissociation of CH{sub 3}SH{sup +} by collisional activation: Observation of non-statistical behavior; High resolution vacuum ultraviolet pulsed field ionization photoelectron band for OCS{sup +}(X{sup 2}{Pi}): An experimental and theoretical study; Rotationally resolved pulsed field ionization ph… more
Date: February 12, 1999
Creator: Stimson, S.
Partner: UNT Libraries Government Documents Department
open access

Historical Exposures to Chemicals at the Rocky Flats Nuclear Weapons Plant: A Pilot Retrospective Exposure Assessment

Description: In a mortality study of white males who had worked at the Rocky Flats Nuclear Weapons Plant between 1952 and 1979, an increased number of deaths from benign and unspecified intracranial neoplasms was found. A case-control study nested within this cohort investigated the hypothesis that an association existed between brain tumor death and exposure to either internally deposited plutonium or external ionizing radiation. There was no statistically significant association found between estimated ra… more
Date: February 1, 1999
Creator: Robertson, Janeen Denise
Partner: UNT Libraries Government Documents Department
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Optically detected magnetic resonance studies on {pi}-conjugate polymers and novel carbon allotropes

Description: This report describes the following: introduction to photoluminescence detected magnetic resonance (PLDMR); introduction to {pi}-conjugated systems; PLDMR measurements on poly(p-phenylene)-type ladder polymers; PLMDR measurements on poly(p-phenylene ethylene); and PLDMR measurements on C{sub 70}, polythiophene, poly(p-phenylene vinylene) and Dan-40. Appendices to this report describe: Operation of ODMR (optically detected magnetic resonance) spectrometer; ODMR system parameters; and Special pur… more
Date: February 12, 1999
Creator: Partee, J.
Partner: UNT Libraries Government Documents Department
open access

Syntheses and studies of organosilicon compounds

Description: The syntheses of polycarbosilanes and polysilanes as silicon carbide ceramic precursors have been active research areas in the Barton Research Group. In this thesis, the work is focused on the preparation of polycarbosilanes and polysilanes as stoichiometric silicon carbide precursor polymers. The syntheses of the precursor polymers are discussed and the conversions of these precursors to silicon carbide via pyrolysis are reported. The XRD pattern and elemental analyses of the resulting silicon… more
Date: February 12, 1999
Creator: Xie, R.
Partner: UNT Libraries Government Documents Department
open access

Single- and multi-photon ionization studies of organosulfur species

Description: Accurate ionization energies (IE`s) for molecular species are used for prediction of chemical reactivity and are of fundamental importance to chemists. The IE of a gaseous molecule can be determined routinely in a photoionization or a photoelectron experiment. IE determinations made in conventional photoionization and photoelectron studies have uncertainties in the range of 3--100 meV (25--250 cm{sup {minus}1}). In the past decade, the most exciting development in the field of photoionization a… more
Date: February 12, 1999
Creator: Cheung, Y. S.
Partner: UNT Libraries Government Documents Department
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Capillary electrophoretic study of individual exocytotic events in single mast cells

Description: The peak profile of individual degranulation events from the on-column release of serotonin from single rat peritoneal mast cells (RPMCs) was monitored using capillary electrophoresis with laser-induced native fluorescence detection (CE-LINF). Serotonin, an important biogenic amine, is contained in granules (0.25 fL) within RPMCs and is extruded by a process termed exocytosis. The secretagogue, Polymyxin B sulfate, was used as the CE running buffer after injection of a single RPMC into the sepa… more
Date: February 12, 1999
Creator: Ho, A.M.W.
Partner: UNT Libraries Government Documents Department
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Capillary electrophoresis separation of neutral organic compounds, pharmaceutical drugs, proteins and peptides, enantiomers, and anions

Description: Addition of a novel anionic surfactant, namely lauryl polyoxyethylene sulfate, to an aqueous-acetonitrile electrolyte makes it possible to separate nonionic organic compounds by capillary electrophoresis. Separation is based on differences in the association between analytes and the surfactant. Highly hydrophobic compounds such as polyaromatic hydrocarbons are well separated by this new surfactant. Migration times of analytes can be readily changed over an unusually large range by varying the a… more
Date: February 12, 1999
Creator: Ding, W.L.
Partner: UNT Libraries Government Documents Department
open access

LiV{sub 2}O{sub 4}: A heavy fermion transition metal oxide

Description: The format of this dissertation is as follows. In the remainder of Chapter 1, brief introductions and reviews are given to the topics of frustration, heavy fermions and spinels including the precedent work of LiV{sub 2}O{sub 4}. In Chapter 2, as a general overview of this work the important publication in Physical Review Letters by the author of this dissertation and collaborators regarding the discovery of the heavy fermion behavior in LiV{sub 2}O{sub 4} is introduced [removed for separate pro… more
Date: February 12, 1999
Creator: Kondo, Shinichiro
Partner: UNT Libraries Government Documents Department
open access

Decomposition of chlorinated ethylenes and ethanes in an electron beam generated plasma reactor

Description: An electron beam generated plasma reactor (EBGPR) is used to determine the plasma chemistry kinetics, energetics and decomposition pathways of six chlorinated ethylenes and ethanes: 1,1,1-trichloroethane, 1,1-dichloroethane, ethyl chloride, trichloroethylene, 1,1-dichloroethylene, and vinyl chloride. A traditional chemical kinetic and chemical engineering analysis of the data from the EBGPR is performed, and the following hypothesis was verified: The specific energy required for chlorinated VOC… more
Date: February 1, 1996
Creator: Vitale, S.A.
Partner: UNT Libraries Government Documents Department
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Gas atomization processing of tin and silicon modified LaNi{sub 5} for nickel-metal hydride battery applications

Description: Numerous researchers have studied the relevant material properties of so-called AB{sub 5} alloys for battery applications. These studies involved LaNi{sub 5} substituted alloys which were prepared using conventional cast and crush alloying techniques. While valuable to the understanding of metal hydride effects, the previous work nearly ignored the potential for alternative direct powder production methods, like high pressure gas atomization (HPGA). Thus, there is a need to understand the relat… more
Date: February 12, 1999
Creator: Ting, J.
Partner: UNT Libraries Government Documents Department
open access

Chiral separation of pharmaceutical compounds using electrochemically modulated liquid chromatography (EMLC)

Description: This research explores the application of a new technique, termed electrochemically modulated liquid chromatography (EMLC), to the chiral separations of pharmaceutical compounds. The introduction section provides a literature review of the technique and its applications, as well as brief overview of the research described in each of the next two chapters. Chapter 2 investigates the EMLC-based enantiomeric separation of a group of chiral benzodiazepines with {beta}-cyclodextrin as a chiral mobil… more
Date: February 12, 1999
Creator: Wang, S.
Partner: UNT Libraries Government Documents Department
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Structure sensitive adsorption of hydrogen on ruthenium and ruthenium-silver catalysts supported on silica

Description: Supported metal catalysts typically consist of particles with sizes less than 10 nm, and because of the small crystallite size, low coordination number sites (edges and corners) represent a significant fraction of all surface sites. Furthermore, it has been demonstrated that adsorption rates can be much greater at these low coordination sites than on basal plane sites. What has not been generally appreciated, however, is that preferential adsorption at edge and corner sites may explain the mech… more
Date: February 12, 1999
Creator: Kumar, N.
Partner: UNT Libraries Government Documents Department
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The analysis of aqueous mixtures using liquid chromatography-electrospray mass spectrometry

Description: The focus of this dissertation is the use of chromatographic methods coupled with electrospray mass spectrometry (ES-MS) for the determination of both organic and inorganic compounds in aqueous solutions. The combination of liquid chromatography (LC) methods and ES-MS offers one of the foremost methods for determining compounds in complex aqueous solutions. In this work, LC-ES-MS methods are devised using ion exclusion chromatography, reversed phase chromatography, and ion exchange chromatograp… more
Date: February 12, 1999
Creator: Johnson, S.
Partner: UNT Libraries Government Documents Department
open access

Calibration of laser ablation inductively coupled plasma mass spectrometry using dried solution aerosols for the quantitative analysis of solid samples

Description: Inductively coupled plasma mass spectrometry (ICP-MS) has become the method of choice for elemental and isotopic analysis. Several factors contribute to its success. Modern instruments are capable of routine analysis at part per trillion levels with relative detection limits in part per quadrillion levels. Sensitivities in these instruments can be as high as 200 million counts per second per part per million with linear dynamic ranges up to eight orders of magnitude. With standards for only a f… more
Date: February 12, 1999
Creator: Leach, J.
Partner: UNT Libraries Government Documents Department
open access

A transport based one-dimensional perturbation code for reactivity calculations in metal systems

Description: A one-dimensional reactivity calculation code is developed using first order perturbation theory. The reactivity equation is based on the multi-group transport equation using the discrete ordinates method for angular dependence. In addition to the first order perturbation approximations, the reactivity code uses only the isotropic scattering data, but cross section libraries with higher order scattering data can still be used with this code. The reactivity code obtains all the flux, cross secti… more
Date: February 1, 1995
Creator: Wenz, T. R.
Partner: UNT Libraries Government Documents Department
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