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Various Acrylic Acid Derivatives as Antispasmodics (open access)

Various Acrylic Acid Derivatives as Antispasmodics

Limitations in the clinical applicability as well as undesireable side effects of the natural antispasmodic drubs, atropine and papaverine, turned early investigators to the problem of developing a more suitable antispasmodic through synthetic procedure.
Date: February 1953
Creator: Holst, Edward Harland
System: The UNT Digital Library
A Study of the Endocrine Glands and Their Implications for Education, with Special Emphasis on Industrial Arts (open access)

A Study of the Endocrine Glands and Their Implications for Education, with Special Emphasis on Industrial Arts

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.
System: The UNT Digital Library
Campaign Tactics of the Arkansas Gubernatorial Elections as Revealed by the 1948, 1950 and 1952 Campaigns (open access)

Campaign Tactics of the Arkansas Gubernatorial Elections as Revealed by the 1948, 1950 and 1952 Campaigns

This thesis is a study of the campaign tactics of the Arkansas gubernatorial elections as revealed by the 1948, 1950 and 1952 campaigns.
Date: February 1953
Creator: Crane, Billy G.
System: The UNT Digital Library
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 (open access)

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

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.
System: The UNT Digital Library
Nitration of Thiophene Analogs of DDT (open access)

Nitration of Thiophene Analogs of DDT

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
System: The UNT Digital Library
The Effect of Auditor Knowledge on Information Processing during Analytical Review (open access)

The Effect of Auditor Knowledge on Information Processing during Analytical Review

Auditors form judgments by integrating the evidence they gather with information stored in memory (knowledge). As they acquire experience, auditors have the opportunity to learn how different patterns of evidence are associated with particular audit problems. Research in experimental psychology has demonstrated that individuals with task-specific experience can match the cues they encounter with patterns they have learned, and form judgments without consciously analyzing the individual cues. Accounting researchers have suggested that auditors develop judgment templates through task-specific experience, and that these knowledge structures automatically provide decisions in familiar situations. I examined whether auditor knowledge leads to reliance on judgment templates. To test this thesis, I synthesized a theoretical framework and developed research hypotheses that predict relationships between task-specific experience (my surrogate for knowledge) and (1) measures of cognitive effort, (2) accuracy of residual memory traces, and (3) performance with respect to identifying potential problems. To test these predictions, I provided senior auditors with comprehensive case materials for a hypothetical client and asked them to use analytical procedures to identify potential audit problems. Subjects acquired information and documented their findings on personal computers using software that I developed to record their activities.
Date: February 1995
Creator: O'Donnell, Ed
System: The UNT Digital Library
A Training Seminar in Human Relations and a Personality Trait Study of Internal Auditors (open access)

A Training Seminar in Human Relations and a Personality Trait Study of Internal Auditors

Little research has been done on the personality of internal auditors. However, there does exist a negative stereotype. They are seen as hostile and unsympathetic. The purpose of this research was to see if the negative stereotype was indeed true and to see if undesirable behavior could be changed through training.
Date: February 1983
Creator: Bull, Dennis L. (Dennis Lee)
System: The UNT Digital Library
The Relationships Among Self-Esteem, Marital Communication, and Marital Adjustment (open access)

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

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 marital adjustment is dependent on married individuals' level of self-esteem and the ability to communicate effectively. It was also concluded that when there is a high level of either self-esteem, marital communiation, or marital adjustment, the other factors will also be at a high level. In addition, the consistency of the relationships among marital adjustment, marital communication, and self-esteem apparently transcend demographic factors.
Date: February 1980
Creator: Carter, Warren Leslie
System: The UNT Digital Library
The Effects Of Structural Setting On The Azimuthal Velocities Of Blast Induced Ground Motion In Perlite (open access)

The Effects Of Structural Setting On The Azimuthal Velocities Of Blast Induced Ground Motion In Perlite

A series of small scale explosive tests were performed during the spring of 1994 at a perlite mine located near Socorro, NM. The tests were designed to investigate the azimuthal or directional relationship between small scale geologic structures such as joints and the propagation of explosively induced ground motion. Three shots were initiated within a single borehole located at ground zero (gz) at depths varying from the deepest at 83 m (272 ft) to the shallowest at 10 m (32 ft). The intermediate shot was initiated at a depth of 63 m (208 ft). An array of three component velocity and acceleration transducers were placed in two concentric rings entirely surrounding the single shot hole at 150 and 300 azimuths as measured from ground zero. Data from the transducers was then used to determine the average propagation velocity of the blast vibration through the rock mass at the various azimuths. The rock mass was mapped to determine the prominent joint orientations (strike and dip) and the average propagation velocities were correlated with this geologic information. The data from these experiments shows that there is a correlation between the orientation of prominent joints and the average velocity of ground motion. It …
Date: February 1, 1995
Creator: Beattie, Susan G.
System: The UNT Digital Library
Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry (open access)

Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry

The fundamental and practical aspects are described for extracting ions from atmospheric pressure plasma sources into an analytical mass spectrometer. Methodologies and basic concepts of inductively coupled plasma mass spectrometry (ICP-MS) are emphasized in the discussion, including ion source, sampling interface, supersonic expansion, slumming process, ion optics and beam focusing, and vacuum considerations. Some new developments and innovative designs are introduced. The plasma extraction process in ICP-MS was investigated by Langmuir measurements in the region between the skimmer and first ion lens. Electron temperature (T{sub e}) is in the range 2000--11000 K and changes with probe position inside an aerosol gas flow. Electron density (n{sub e}) is in the range 10{sup 8}--10{sup 10} {sup {minus}cm }at the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} near the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} downstream further behind the skimmer. Electron density in the beam leaving the skimmer also depends on water loading and on the presence and mass of matrix elements. Axially resolved distributions of electron number-density and electron temperature were obtained to characterize the ion beam at a variety of plasma operating conditions. The electron density dropped by a factor of 101 …
Date: February 10, 1995
Creator: Niu, Hongsen
System: The UNT Digital Library
Intermolecula transfer and elimination of molecular hydrogen in thermal reactions of unsaturated organic compounds (open access)

Intermolecula transfer and elimination of molecular hydrogen in thermal reactions of unsaturated organic compounds

Two reactions which are important to coal liquefaction include intermolecular transfer and the elimination of two hydrogen atoms. We have designed several model reactions to probe the viability of several hydrogen transfer and elimination pathways. This report described studies on these reactions using organic model compounds.
Date: February 10, 1995
Creator: Suria, S.
System: The UNT Digital Library
NMR and NQR study of the thermodynamically stable quasicrystals (open access)

NMR and NQR study of the thermodynamically stable quasicrystals

{sup 27}Al and {sup 61,65}Cu NMR measurements are reported for powder samples of stable AlCuFe and AlCuRu icosahedral quasicrystals and their crystalline approximants, and for a AlPdMn single grain quasicrystal. Furthermore, {sup 27}Al NQR spectra at 4.2 K have been observed in the AlCuFe and AlCuRu samples. From the quadrupole perturbed NMR spectra at different magnetic fields, and from the zero field NQR spectra, a wide distribution of local electric field gradient (EFG) tensor components and principal axis system orientations was found at the Al site. A model EFG calculation based on a 1/1 AlCuFe approximant was successful in explaining the observed NQR spectra. It is concluded that the average local gradient is largely determined by the p-electron wave function at the Al site, while the width of the distribution is due to the lattice contribution to the EFG. Comparison of {sup 63}Cu NMR with {sup 27}Al NMR shows that the EFG distribution at the two sites is similar, but that the electronic contribution to the EFG is considerably smaller at the Cu site, in agreement with a more s-type wave function of the conduction electrons.
Date: February 10, 1995
Creator: Shastri, A.
System: The UNT Digital Library
The History of the Gainesville XLI Club and Its Relation to the General Women's Club Movement (open access)

The History of the Gainesville XLI Club and Its Relation to the General Women's Club Movement

"The organized woman's club movement spread into the State of Texas. Beginning as associations for self-culture and intellectual development, the clubs were soon laying the foundation for better conditions of living in their communities. Since Texas was largely in the pioneer stage of development with widely separated communities, the women's clubs in small centers became the nucleii for civic improvements. One of these small centers was the town of Gainesville, Texas, with a population of about 6,000 in the year 1893. That year the first women's club in the town was organized and named the Gainesville XLI Club. This club helped form the State Council of Women of Texas, formerly called the Women's Congress, in 1894, which was three years before the formation of the Texas Federation of Women's Clubs."-- pg. 9-10 "It will, perhaps, be seen from the above survey that no transformation in modern society has been more striking or more fraught with significance than the change in the political, legal, economic, moral, and social status of women. Women's clubs were organized for discussion and study, with interests that varied according to location, surroundings, opportunities, and aspirations. The history of a pioneer club portrays the stages of development …
Date: February 1951
Creator: Culp, Bengta A.
System: The UNT Digital Library
A Study and Evaluation of Certain Practices of the Financial Administration of Industrial Arts Departments in Class A High Schools of Texas (open access)

A Study and Evaluation of Certain Practices of the Financial Administration of Industrial Arts Departments in Class A High Schools of Texas

This is a study and evaluation of certain practices in the financial administration of industrial arts programs operating in accredited four-year class "A" high schools in Texas. The study seeks to answer the following questions: 1. Are industrial arts teachers properly prepared to administer the financial transactions involved in an industrial arts program? 2. Is there a need for establishing standard practices and principles to be used in administering industrial arts finance? 3. Is there a danger of criticism of the industrial arts departments and the teachers, because of inefficiency in the administration of shop finance? 4. Are practices now in use basically sound? 5. Are adequate records being kept? 7. What steps should be taken to eliminate the objectional practices now in use and to initiate the more desirable ones?
Date: February 1951
Creator: Anderson, Ward
System: The UNT Digital Library
A transport based one-dimensional perturbation code for reactivity calculations in metal systems (open access)

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

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 section, and geometry data from the standard interface files created by ONEDANT, a discrete ordinates transport code. Comparisons between calculated and experimental reactivities were done with the central reactivity worth data for Lady Godiva, a bare uranium metal assembly. Good agreement is found for isotopes that do not violate the assumptions in the first order approximation. In general for cases where there are large discrepancies, the discretized cross section data is not accurately representing certain resonance regions that coincide with dominant flux groups in the Godiva assembly. Comparing reactivities calculated with first order perturbation theory and a straight {Delta}k/k calculation shows agreement within 10% indicating the perturbation of the calculated fluxes is small enough for first order perturbation theory to be applicable in the modeled system. Computation time comparisons …
Date: February 1, 1995
Creator: Wenz, T. R.
System: The UNT Digital Library
Development of a high-resolution soft x-ray (30--1500 eV) beamline at the Advanced Light Source and its use for the study of angle-resolved photoemission extended fine structure (open access)

Development of a high-resolution soft x-ray (30--1500 eV) beamline at the Advanced Light Source and its use for the study of angle-resolved photoemission extended fine structure

ALS Bending magnet beamline 9.3.2 is for high resolution spectroscopy, with circularly polarized light. Fixed included-angle SGM uses three gratings for 30--1500 eV photons; circular polarization is produced by an aperture for selecting the beam above or below the horizontal plane. Photocurrent from upper and lower jaws of entrance slit sets a piezoelectric drive feedback loop on the vertically deflecting mirror for stable beam. End station has a movable platform. With photomeission data from Stanford, structure of c(2{times}2)P/Fe(100) was determined using angle-resolved photoemission extended fine structure (ARPEFS). Multiple-scattering spherical-wave (MSSW) calculations indicate that P atoms adsorb in fourfold hollow sites 1.02A above the first Fe layer. Self-consistent-field X{alpha} scattered wave calculation confirm that the Fe{sub 1}-Fe{sub 2} space is contracted for S/Fe but not for P/Fe; comparison is made to atomic N and O on Fe(100). Final-state effects on ARPEFS curves used literature data from the S 1s and 2p core levels of c(2{times}2)S/Ni(001); a generalized Ramsauer-Townsend splitting is present in the 1s but not 2p data. An approximate method for analyzing ARPEFS data from a non-s initial state using only the higher-{ell} partial wave was tested successfully. ARPEFS data from clean surfaces were collected normal to Ni(111) (3p core …
Date: February 1, 1996
Creator: Huff, W. R. A.
System: The UNT Digital Library
Solid phase epitaxial regrowth of (100)GaAs (open access)

Solid phase epitaxial regrowth of (100)GaAs

This thesis showed that low temperature (250 C) SPE of stoichiometrically balanced ion implanted GaAs layers can yield good epitaxial recovery for doses near the amorphization threshold. For 250 C anneals, most of the regrowth occurred in the first 10 min. HRTEM revealed much lower stacking fault density in the co-implanted sample than in the As-only and Ga-only samples with comparable doses. After low temp annealing, the nonstoichiometric samples had a large number of residual defects. For higher dose implants, very high temperatures (700 C) were needed to remove residual defects for all samples. The stoichiometrically balanced layer did not regrow better than the Ga-only and As-only samples. The co-implanted sample exhibited a thinner amorphous layer and a room temperature (RT) annealing effect. The amorphous layer regrew about 5 nm, suggesting that stoichiometrically balanced amorphous layers can regrow even at RT. Mechanisms for solid phase crystallization in (100)GasAs is discussed: nucleation and growth of randomly oriented crystallites and SPE. These two mechanisms compete in compound semiconductors at much lower temperatures than in Si. For the low dose As-only and Ga-only samples with low-temp anneals, both mechanisms are active. For this amorphization threshold dose, crystallites remain in the amorphous layer for …
Date: February 1, 1996
Creator: Almonte, M. I.
System: The UNT Digital Library
Development of a new Pb-free solder: Sn-Ag-Cu (open access)

Development of a new Pb-free solder: Sn-Ag-Cu

With the ever increasing awareness of the toxicity of Pb, significant pressure has been put on the electronics industry to get the Pb out of solder. This work pertains to the development and characterization of an alloy which is Pb-free, yet retains the proven positive qualities of current Sn-Pb solders while enhancing the shortcomings of Sn-Pb solder. The solder studied is the Sn-4.7Ag-1.7Cu wt% alloy. By utilizing a variety of experimental techniques the alloy was characterized. The alloy has a melting temperature of 217{degrees}C and exhibits eutectic melting behavior. The solder was examined by subjecting to different annealing schedules and examining the microstructural stability. The effect of cooling rate on the microstructure of the solder was also examined. Overall, this solder alloy shows great promise as a viable alternative to Pb-bearing solders and, as such, an application for a patent has been filed.
Date: February 10, 1995
Creator: Miller, C. M.
System: The UNT Digital Library
Computational modeling of neoclassical and resistive MHD tearing modes in tokamaks (open access)

Computational modeling of neoclassical and resistive MHD tearing modes in tokamaks

Numerical studies of the linear and nonlinear evolution of magnetic tearing type modes in three-dimensional toroidal geometry are presented. In addition to traditional resistive MHD effects, where the parameter {Delta}{prime} determines the stability properties, neoclassical effects have been included for the first time in such models. The inclusion of neoclassical physics introduces and additional free-energy source for the nonlinear formation of magnetic islands through the effects of a bootstrap current in Ohm`s law. The neoclassical tearing mode is demonstrated to be destabilized in plasmas which are otherwise {Delta}{prime} stable, albeit once an island width threshold is exceeded. The simulations are based on a set of neoclassical reduced magnetohydrodynamic (MHD) equations in three-dimensional toroidal geometry derived from the two-fluid equations in the limit of small inverse aspect ratio {epsilon} and low plasma pressure {beta} with neoclassical closures for the viscous force {del} {center_dot} {leftrightarrow}{pi}. The poloidal magnetic flux {psi}, the toroidal vorticity {omega}{sup {zeta}}, and the plasma pressure p are time advanced using the parallel projection of Ohm`s law, the toroidal projection of the curl of the momentum equation, and a pressure evolution equation with anisotropic pressure transport parallel to and across magnetic field lines. The equations are implemented in an …
Date: February 1, 1996
Creator: Gianakon, T.A.
System: The UNT Digital Library
Electronic processes in uniaxially stressed p-type germanium (open access)

Electronic processes in uniaxially stressed p-type germanium

Effect of uniaxial stress on acceptor-related electronic processes in Ge single crystals doped with Ga, Be, and Cu were studied by Hall and photo-Hall effect measurements in conjunction with infrared spectroscopy. Stress dependence of hole lifetime in p-type Ge single crystals is used as a test for competing models of non-radiative capture of holes by acceptors. Photo-Hall effect shows that hole lifetime in Ga- and Be-doped Ge increases by over one order of magnitude with uniaxial stress at liq. He temps. Photo-Hall of Ge:Be shows a stress-induced change in the temperature dependence of hole lifetime. This is consistent with observed increase of responsivity of Ge:Ga detectors with uniaxial stress. Electronic properties of Ge:Cu are shown to change dramatically with uniaxial stress; the results provide a first explanation for the performance of uniaxially stressed, Cu-diffused Ge:Ga detectors which display a high conductivity in absence of photon signal and therefore have poor sensitivity.
Date: February 1, 1996
Creator: Dubon, O.D. Jr.
System: The UNT Digital Library
Collision-induced dissociation reactions and pulsed field ionization photoelectron (open access)

Collision-induced dissociation reactions and pulsed field ionization photoelectron

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 photoelectron bands of H{sub 2}{sup +} ({Chi}{sup 2}{Sigma}{sup +}{sub g}, v{sup +} = 0--18); and Rotationally resolved pulsed field ionization photoelectron bands of HD{sup +} ({Chi}{sup 2}{Sigma}{sup +}, v{sup +} = 0--21).
Date: February 12, 1999
Creator: Stimson, S.
System: The UNT Digital Library
Historical Exposures to Chemicals at the Rocky Flats Nuclear Weapons Plant: A Pilot Retrospective Exposure Assessment (open access)

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

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 radiation exposure from internally deposited plutonium and the development of brain tumors. Exposure by job or work area showed no significant difference between the cohort and the control groups. An update of the study found elevated risk estimates for (1) all lymphopoietic neoplasms, and (2) all causes of death in employees with body burdens greater than or equal to two nanocuries of plutonium. There was an excess of brain tumors for the entire cohort. Similar cohort studies conducted on worker populations from other plutonium handling facilities have not yet shown any elevated risks for brain tumors. Historically, the Rocky Flats Nuclear Weapons Plant used large quantities of chemicals in their production operations. The use of solvents, particularly carbon tetrachloride, was unique to Rocky Flats. No investigation of the …
Date: February 1, 1999
Creator: Robertson, Janeen Denise
System: The UNT Digital Library
Optically detected magnetic resonance studies on {pi}-conjugate polymers and novel carbon allotropes (open access)

Optically detected magnetic resonance studies on {pi}-conjugate polymers and novel carbon allotropes

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 purpose circuitry.
Date: February 12, 1999
Creator: Partee, J.
System: The UNT Digital Library
Syntheses and studies of organosilicon compounds (open access)

Syntheses and studies of organosilicon compounds

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 carbide ceramics are presented. Silicon monoxide is an important intermediate in the production of silicon metal. The existence of silicon monoxide in gap phase has been widely accepted. In the second part of this thesis, the generation of gaseous silicon monoxide in four different reactors and the reactions of gaseous silicon monoxide towards organic compounds are discussed.
Date: February 12, 1999
Creator: Xie, R.
System: The UNT Digital Library