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1. Mono([8]annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes
A reproducible, high-yield synthesis of mono([8]annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono([8]annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.
Date:
October 1, 1991
Creator:
Boussie, T. R.
System:
The UNT Digital Library
AC microcalorimetry of adsorbates on evaporated metal films: Orientational ordering of H₂ multilayers
We have improved and extended a novel ac calorimetric technique for measuring the heat capacity of adsorbates on evaporated metal films. Metallic substrates are of particular interest in current studies of the thermodynamics of adsorbed molecules. The method described in the present work is only calorimetric technique which allows measurements of molecules on simple metallic surfaces. Among other improvements, we have achieved significant progress in the preparation and characterization of the evaporated metal film. We have applied this novel technique to a study of hydrogen multilayers on gold and sapphire substrates. We have shown that samples of normal-hydrogen with a nominal coverage n of approximately 25 monolayers (ML) undergo a bulk-like orientational ordering transition. The transition is suppressed as the coverage is decreased, and no sign of the transition remains above 1.6 K for n {approx} 1 ML. For n {approx_lt} 8 ML, the peak in the heat capacity exhibits signs of finite-size effects. At higher coverages, finite-size effects are not observed, and the shape of the peak depends strongly on the substrate. We conclude that the peak is inhomogeneously broadened for n {approx_lt} 8 ML. This work represents the first measurements of the heat capacity due to orientational ordering …
Date:
November 1, 1991
Creator:
Phelps, R. B.
System:
The UNT Digital Library
Additional evidence on informational asymmetry at acquisition announcement
This dissertation examines the partial anticipation hypothesis by employing the bid-ask spread approach in market microstructure theory. Selecting the OTC bidding firms with a careful research design, this dissertation divides sample firms into firms with acquisition programs and firms without acquisition programs.
Date:
August 1991
Creator:
Kim, Young Kook
System:
The UNT Digital Library
Adenosine and Down-Regulation of Myocardial Oxygen Demand
This investigation studied the physiological means by which myocardium can survive and function properly when oxygen supply is limited and cannot initially match oxygen demand. The effects of isoproterenol (ISO) stimulations during low coronary perfusion pressure or hypoxemia on myocardial oxygen demand, work, and oxygen utilization efficiency were investigated.
Date:
December 1991
Creator:
Lee, Shang Chiun
System:
The UNT Digital Library
Adlerian Life-Style, Social Interest, and Job Satisfaction Among Catholic Priests
The purpose of this study was to seek an understanding of the problem of low morale among Catholic priests based on the principles of Individual Psychology. The relationship of Adlerian life-style and social interest to job satisfaction among 210 pastors randomly selected from 13 of the 14 Catholic dioceses in Texas was investigated. The Life-style Personality Inventory (LSPI) was used to measure the Adlerian life-style. The Social Interest Scale (SIS) was used to measure the Adlerian concept of social interest. The Job Descriptive Index (JDI) was used to measure job satisfaction.
Date:
May 1991
Creator:
Ugwokaegbe, Paul U. (Paul Ugochukwu)
System:
The UNT Digital Library
Adult Age and Ethnicity as Factors in Success on the TASP : A Measurement of the Texas Academic Skills Program (TASP) Test
This study examined the association among ethnicity, age, and scores on selected portions of the TASP and MAPS tests. This study further examined if the TASP could identify students for success in college level course work as well or better than selected portion of the MAPS test.
Date:
August 1991
Creator:
Friedman, Linda A. (Linda Anne)
System:
The UNT Digital Library
Age Differences in Time Estimation and Their Relationship to Prospective Memory
This paper discusses a study conducted with 34 elderly volunteers and 34 young subjects to determine the differences in time estimation by age and their reflection in prospective memory. Kirk Rowe explains the reproduction, production, and numerical estimation tasks carried out, the scores of the subjects, and the findings of the study.
Date:
December 1991
Creator:
Rowe, Kirk
System:
The UNT Digital Library
AIDS and Higher Education in Texas: Policies at Accredited Institutions
This study of all of the post secondary institutions accredited by the Commission on Colleges of the Southern Association of Colleges and Schools which were located in Texas determined the number that had policies regarding persons with AIDS. The study determined how long policies had been in effect and analyzed policies in order to determine commonalities and differences. An additional purpose was to examine relationships between five major variables and 18 topics which were identified as being issues likely to be addressed in institutional AIDS policies.
Date:
May 1991
Creator:
Gunn, Paul W. (Paul Wayne)
System:
The UNT Digital Library
An algebraic characterization of stability groups
The goal of this paper is to establish necessary and sufficient conditions for a subgroup of the full homeomorphism group of a manifold to be the stability group of a point in the underlying space. Such subgroups are useful in identifying the underlying space in terms of its homeomorphism group even in cases in which this space is not necessarily a manifold. Thus, stability groups are useful in classifying various spaces.
Date:
August 1991
Creator:
Wright, William G. (William Glenn)
System:
The UNT Digital Library
Algebraic Number Fields
This thesis investigates various theorems on polynomials over the rationals, algebraic numbers, algebraic integers, and quadratic fields. The material selected in this study is more of a number theoretical aspect than that of an algebraic structural aspect. Therefore, the topics of divisibility, unique factorization, prime numbers, and the roots of certain polynomials have been chosen for primary consideration.
Date:
August 1991
Creator:
Hartsell, Melanie Lynne
System:
The UNT Digital Library
Aminoketene. Cycloaddition of Ketenes and Imines to Yield β- or δ- Lactams
The purpose of this investigation was to provide a systematic study of the cycloaddition pf (N-alkyl-N-phenylamino)- methoxy-and dichloroketenes to various imines and to investigate the stereochemistry of these cycloadditions.
Date:
December 1991
Creator:
Dad, Mohammad M. (Mohammad Mehdj)
System:
The UNT Digital Library
An amplitude analyses of the K K-bar system (M < 2 GeV/C{sup 2}) produced in J/{Psi} radiative decay
Using the 5.8 {times} 10{sup 6} J/{psi} events collected by the MARK 3 experiment on the SPEAR e{sup +}e{sup {minus}} storage ring at SLAC, a mass independent amplitude analysis of the J/{psi} {yields} {gamma} K{sub s}K{sub s} and J/{psi} {yields} K{sup +}K{sup {minus}} decays is presented. For K{bar K} systems having mass less than 2 GeV/c{sup 2}, the efficiency-corrected spherical harmonic moments of the J/{psi} joint decay angular distribution are measured. Fits are then performed in each independent mass interval in order to extract the underlying helicity amplitude structure; amplitudes describing K{bar K} systems of spin zero and spin two are included simultaneously. For the first time, a large spin zero component in the {theta}(1720) mass region is observed; consistent results are obtained for the data samples corresponding to the individual decay modes. This structure is attributed to the production of an S wave resonance, the f{sub 0}(1710), of mass and width M = 1710 {plus_minus} 10 MeV/c{sup 2}, {Gamma} = 186 {plus_minus} 30 MeV/c{sup 2}, respectively, with branching fraction Bf(J/{psi} {yields} {gamma}f{sub 0}, f{sub 0} {yields} K{bar K}) = (6.47 {plus_minus} 1.14 {plus_minus} 0.84) {times} 10{sup {minus}4}. A small amount ({approximately}24%) of spin two component in this mass region …
Date:
November 1, 1991
Creator:
Chen, Liang-Ping
System:
The UNT Digital Library
An analysis of absenteeism cases taken to arbitration: factors used by arbitrators in the decision-making process
The purpose of this study was to examine factors used by arbitrators in deciding the outcome of disciplinary labor arbitration cases involving excessive employee absenteeism. The seven key tests of just cause identified by Carroll Daugherty in the 1966 Enterprise Wire Co. arbitration case were used as the basis for examining the cases in the study.
Date:
May 1991
Creator:
Clay, Joan Marie
System:
The UNT Digital Library
An Analysis of Elements of Jazz Style in Contemporary French Trumpet Literature
French trumpet works comprise a large portion of the contemporary standard repertoire for the instrument, and they frequently present unique stylistic and interpretive challenges to performers. The study establishes the influence of jazz upon Henri Tomasi, André Jolivet, Eugène Bozza and Jacques Ibert in their works for solo trumpet. Idiomatic elements of jazz style are identified and discussed in terms of performance practice considerations for modern-day trumpeters.
Date:
August 1991
Creator:
Schmid, William A. (William Albert)
System:
The UNT Digital Library
An Analysis of Refuse Derived Fuel as an Environmentally Acceptable Fuel Alternative for the Cement Industry
Resource recovery is an attractive alternative to the waste disposal problem. The chief by-product of this process, refuse derived fuel (RDF) can be co-fired in traditional coal burning facilities. The cement industry is a potential user of RDF. This study, based on a test burn done at Texas Industries Inc. in Midlothian, Texas, demonstrated the technical, environmental, and economic feasibility of using RDF fuel in a cement kiln. Technically, the cement showed no deleterious effects when RDF was substituted for coal/natural gas at 20% by Btu content. Environmentally, acid rain gases were reduced. Economically, RDF was shown to be a cost effective fuel substitute if a resource recovery facility was erected on site.
Date:
May 1991
Creator:
Brooks, Cheryl L. (Cheryl Leigh)
System:
The UNT Digital Library
An Analysis of Retained Two Dimensional Elements in a Three Dimensional Sculptural Format
The object of this problem in lieu of thesis has been the exploration and identification of the retained two dimensional design idiom in the sculptural format of my work. (By this, I am referring to the lateral, planar quality which often continues as part of my designs.)
Date:
December 1991
Creator:
Trimble, H. Carl III
System:
The UNT Digital Library
An Analysis of the Information Content of Bond-Rating Changes: A Case of Differential Information
This dissertation examines the reaction of common stock prices to the announcement of changes in bond ratings by Moody's Bond Service, while having a control for differential information availability. The Institutional Brokers Estimate System (I/B/E/S) number of security analysts and coefficient of variation of earning per share (EPS) estimates are used as a proxy for information availability of the firms. Past studies differs in their conclusions as to whether the market has responded to announcement of bond rating changes. None of past studies have controlled for differential information availability. This study, using daily stock returns data and the event study methodology with the statistical test, finds that while the sample of rating downgrades exhibit significantly negative abnormal price effect during the announcement period, the magnitude of this effect is significantly higher for firms with low information availability. For the rating upgrades, the sample as a whole has no abnormal announcement period returns, but the sample of firms with lower information earns significantly positive abnormal returns. This study provides support for the hypothesis that the announcement effect of bond-rating changes is conditional on the information available about the firm.
Date:
May 1991
Creator:
Pongspaibool, Nantaphol
System:
The UNT Digital Library
An Analysis of the Utilization of the Work Measurement System Requirements of Military Standard 1567a as Compared to Standard Operating Procedures
Work measurement systems are widely used by American manufacturers in establishing labor standards as inputs for budgeting, estimating, planning, evaluating, and managing production. These systems are used by defense related and non-defense related contractors alike. However in 1987, their use was required in United States Air Force major procurement contracts through Military Standard 1567A.
Date:
May 1991
Creator:
Ekholm, Harry H. (Harry Hilding)
System:
The UNT Digital Library
The Angel in the House and The Woman in White: The Unfolding and Decoding of a Victorian Stereotype
Abstract: Modern readers frequently perceive female characters in Victorian novels as insipid and inane, blaming the static portrayals on the angel in the house stereotype attributed to Coventry Patmore's poem of the same name. The stereotype does not accurately reflect the actual Victorian woman's life, however. Examining how the stereotype evolved and how the middle-class Mid-Victorian woman really lived provides insight into literary devices authors employed either to reinforce the angel ideal or to reconcile the ideal with the real. Wilkie Collins's portrayal of Marian Halcombe in The Woman in White features a dynamic female who has both androgynous characteristics and angel-in-the-house qualities, exemplifying one more paradox in a society riddled with contradictions.
Date:
August 1991
Creator:
Spencer, Sandra L.
System:
The UNT Digital Library
Anisotropy of conduction electrons in n-InSb and extrinsic and intrinsic properties of HgCdTe
The anistropy of the orbital and spin properties of conduction electrons in InSb has been measured simultaneously using a cyclotron-resonance type experiment. This represents the first time that the anistropy of effective mass in InSb has been directly measured using an optical method.
Date:
August 1991
Creator:
Yoon, Im T. (Im Taek)
System:
The UNT Digital Library
Antecedents of Power in the Distribution Channel : A Transaction-cost Perspective
A discussion of reward, coercive, expert, legitimate, and referent power bases was the initial focus of this research. A review of the power sources literature suggested that vertical integration within a channel of distribution was a crucial precursor to develop a structure to facilitate the use of power without creating a significant conflict among channel participants. Elements of transaction cost analysis (TCA) were offered as being suitable for determining the existing level of vertical integration among respondent firms. Accordingly, the purpose of this study was to develop a tentative model to determine proper use of power within varying levels of vertical integration.
Date:
August 1991
Creator:
Erdem, S. Altan (Selim Altan)
System:
The UNT Digital Library
Application of a canine {sup 238}Pu dosimetry model to human bioassay data
Associated with the use of 2{sup 238}Pu in thermoelectric power sources for space probes and power supplies for cardiac devices is the potential for human exposure to {sup 238}Pu, primarily by inhalation. In the event of human internal exposure, a means is needed for assessing the level of intake and calculating radiation doses. Several bioassay/dosimetry models have been developed for {sup 239}Pu. However, results from studies with laboratory animals have indicated that the biokinetics, and therefore the descriptive models, of {sup 238}Pu are significantly different from those for {sup 239}Pu. A canine model accounting for these differences has been applied in this work to urinary excretion data from seven humans occupationally exposed to low levels of an insoluble {sup 238}Pu compound. The modified model provides a good description of the urinary excretion kinetics observed in the exposed humans. The modified model was also used to provide estimates of the initial intakes of {sup 238}Pu for the seven individuals; these estimates ranged from 4.5 nCi (170 Bq) to 87 nCi (3200 Bq). Autopsy data on the amount and distribution of {sup 238}Pu retained in the organs may be used in the future to validate or refute both these estimates and the …
Date:
August 1, 1991
Creator:
Hickman, A. W. Jr.
System:
The UNT Digital Library
The application of psoralens to the study of DNA structure, function and dynamics
A series of six nitroxide spin-labeled psoralens were designed, synthesized and tested as probes for DNA dynamics. The synthesis of these spin-labeled psoralen derivatives and their photoreactivity with double-stranded DNA fragments is described. The spin labels (nitroxides) were demonstrated to survive the uv irradiation required to bind the probe to the target DNA. EPR spectra of the photobound spin-labels indicate that they do not wobble with respect to the DNA on the time-scales investigated. The author has used psoralen modified DNA as a model for the study of DNA repair enzyme systems in human cell free extracts. He has shown that damage-induced DNA synthesis is associated with removal of psoralen adducts and therefore is {open_quotes}repair synthesis{close_quotes} and not an aberrant DNA synthesis reaction potentiated by deformation of the DNA by adducts. He has found that all DNA synthesis induced by psoralen monoadducts is the consequence of removal of these adducts. By the same approach he has obtained evidence that this in vitro system is capable of removing psoralen cross-links as well. Reported here are synthetic methods that make use of high intensity lasers coupled with HPLC purification to make homogeneous and very pure micromole quantities of furan-side monoadducted, cross-linked, and …
Date:
April 1, 1991
Creator:
Spielmann, P. H.
System:
The UNT Digital Library
The application of the symmetry properties of optical second harmonic generation to studies of interfaces and gases
Optical second harmonic generation has proven to be a powerful tool for studying interfaces. The symmetry properties of the process allow for surface sensitivity not available with other optical methods. In this thesis, we take advantage of these symmetry properties SHG to study a variety of interesting systems not previously studied with this technique. We show that optical second harmonic generation is an effective surface probe with a submonolayer sensitivity for media without inversion symmetry. We demonstrate the technique at a gallium arsenide surface, exploiting the different symmetry properties of the bulk and surface of the crystal to isolate the surface contribution. We also demonstrate that optical second harmonic generation can be used to determine the anisotropic orientational distribution of a surface monolayer of molecules. We apply the technique to study homogeneously aligned liquid crystal cells. To further explore the LC-polymer interface, we used SHG to study the surface memory effect. The surface memory effect is the rendering of an isotropic interface anisotropic by putting it in contact with an anisotropic bulk. Last, we describe some preliminary measurements of a time-resolved spectroscopic study of the phenomenon of second harmonic generation in a gas. The construction of a 500 microjoule pulsed, …
Date:
November 1, 1991
Creator:
Feller, M. B.
System:
The UNT Digital Library