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Atomic and Molecular Photoelectron and Auger Electron SpectroscopyStudies Using Synchrotron Radiation

Description: Electron spectroscopy, combined with synchrotron radiation, was used to measure the angular distributions of photoelectrons and Auger electrons from atoms and molecules as functions of photon energy. The branching ratios and partial cross sections were a 130 measured in certain cases. By comparison with theoretical calculations, the experimental results are interpreted in terms of the characteristic electronic structure and ionization dynamics of the atomic or molecular sample. The time structure of the synchrotron radiation source was used to record time-of-flight (TOF) spectra o f the ejected electrons. The ''a double-angle-TOF'' method for the measurement of photoelectron angular distributions is discussed. This technique offers the advantages of increased electron collect ion efficiency and the elimination of certain systematic errors. Several results were obtained for Xe using photon energies in the range hv {approx_equal} 60-190 eV, where excitation and ionization of the inner-subshell 4d electrons dominates. The 4d asymmetry parameter {beta} exhibits strong oscillations with energy, in agreement with several theoretical calculations. As predicted, the 5p asymmetry parameter was observed to deviate strongly from that calculated using the independent-electron model, due to intershell correlation with the 4d electrons.
Date: January 1, 1982
Creator: Southworth, Stephen H.
Partner: UNT Libraries Government Documents Department

An Adaptive Finite Difference Method for Hyperbolic Systems in OneSpace Dimension

Description: Many problems of physical interest have solutions which are generally quite smooth in a large portion of the region of interest, but have local phenomena such as shocks, discontinuities or large gradients which require much more accurate approximations or finer grids for reasonable accuracy. Examples are atmospheric fronts, ocean currents, and geological discontinuities. In this thesis we develop and partially analyze an adaptive finite difference mesh refinement algorithm for the initial boundary value problem for hyperbolic systems in one space dimension. The method uses clusters of uniform grids which can ''move'' along with pulses or steep gradients appearing in the calculation, and which are superimposed over a uniform coarse grid. Such refinements are created, destroyed, merged, separated, recursively nested or moved based on estimates of the local truncation error. We use a four-way linked tree and sequentially allocated deques (double-ended queues) to perform these operations efficiently. The local truncation error in the interior of the region is estimated using a three-step Richardson extrapolation procedure, which can also be considered a deferred correction method. At the boundaries we employ differences to estimate the error. Our algorithm was implemented using a portable, extensible Fortran preprocessor, to which we added records and pointers. The method is applied to three model problems: the first order wave equation, the second order wave equation, and the inviscid Burgers equation. For the first two model problems our algorithm is shown to be three to five times more efficient (in computing time) than the use of a uniform coarse mesh, for the same accuracy. Furthermore, to our knowledge, our algorithm is the only one which adaptively treats time-dependent boundary conditions for hyperbolic systems.
Date: June 1, 1982
Creator: Bolstad, John H.
Partner: UNT Libraries Government Documents Department

ANALYSIS OF THE PERFORMANCE AND COST EFFECTIVENESS OF NINE SMALL WIND ENERGY CONVERSION SYSTEMS FUNDED BY THE DOE SMALL GRANTS PROGRAM

Description: This report presents an analysis of the technical performance and cost effectiveness of nine small wind energy conversion systems (SWECS) funded during FY 1979 by the U.S. Department of Energy. Chapter 1 gives an analytic framework with which to evaluate the systems. Chapter 2 consists of a review of each of the nine projects, including project technical overviews, estimates of energy savings, and results of economic analysis. Chapter 3 summarizes technical, economic, and institutional barriers that are likely to inhibit widespread dissemination of SWECS technology.
Date: April 1, 1982
Creator: Kay, J.
Partner: UNT Libraries Government Documents Department

Assessment center performance of volunteers and nonvolunteers

Description: The present study compares the performance of volunteers and nonvolunteers in a 10-hour integrated series of management simulation exercises. It was hypothesized that there would be no performance differences in these two groups. Subjects were business students.
Date: May 1982
Creator: Cunningham, Howard Michael
Partner: UNT Libraries

Twenty-one original prose selections for use in teaching oral interpretation in junior high and high school

Description: Twenty-one original prose selections were written for use by junior high school students of oral interpretation. A survey of textbook publishers and junior high school teachers revealed a need for material of appropriate length and of suitable reading and interest levels for oral reading in the junior high school classroom. The selections were read and evaluated by a group of junior high students and a junior high teacher of speech. The responses indicate that the selections are effective and usable as an instructional aid in teaching oral interpretation in junior high school.
Date: May 1982
Creator: Bohlcke, Diane
Partner: UNT Libraries

A multivariate model for testing the information content of constant dollar disclosures required by statement of financial reporting and changing prices (FASB No. 33)

Description: In September 1979, the Financial Accounting Standards Board (FASB) issued a statement entitled Financial Reporting and Changing Prices (FASB No. 33). FASB No. 33 requires publicly-held companies of a certain size to issue supplementary constant dollar and current cost disclosures along with their primary financial statements.
Date: December 1982
Creator: Moustafa, Salah El din
Partner: UNT Libraries

Relationship of characteristics of the research methods used in two subfields of geology and the growth of published research in those subfields

Description: The major problem addressed by this study was to investigate the relationship between characteristics of the research methods used in selected subject subfields. In order to carry out the investigation a non-experimental design was employed, and an evaluative instrument was developed for assigning a quantitative score to published research based on characteristics of the research methods utilized. Evaluative scores were thus assigned to 244 randomly selected research studies drawn from two scientific subfields manifesting different rates of growth.
Date: December 1982
Creator: Stephenson, Mary Sue
Partner: UNT Libraries

The perceptions of teachers of United States history in traditionally black colleges with regard to their efforts to promote cognitive development in students

Description: The problem for this investigation was the extent to which instruction in the traditionally black colleges and universities was directed toward higher cognitive skills as perceived by teachers of United States history in these institutions.
Date: August 1982
Creator: Johnson, Stanley W. (Stanley Webster)
Partner: UNT Libraries

An analytical survey of educators' attitudes toward competency testing

Description: This study addresses the attitudes of counselors, teachers, and administrators toward competency testing programs in their districts. ten districts from each of the four states --Arizona, California, Michigan, and Oregon-- were randomly selected to participate in the study. A total of 247 educators responded to the survey.
Date: August 1982
Creator: Landers, Maria Anne
Partner: UNT Libraries

The chi square approximation to the hypergeometric probability distribution

Description: This study compared the results of his chi square text of independence and the corrected chi square statistic against Fisher's exact probability test (the hypergeometric distribution) in contection with sampling from a finite population. Data were collected by advancing the minimum call size from zero to a maximum which resulted in a tail area probability of 20 percent for sample sizes from 10 to 100 by varying increments.
Date: August 1982
Creator: Anderson, Randy J. (Randy Jay)
Partner: UNT Libraries

Correlates of perceived computer helplessness

Description: The purpose of this investigation was to determine the relationship between computer experience and selected demographic variables to knowledge about computers; knowledge of computers, experience with computers and selected demographic variables and attitudes towards computers to perceived computer helplessness.
Date: December 1982
Creator: Macdonald, Susan M. (Susan Marie)
Partner: UNT Libraries

Marital satisfaction in returning female students

Description: One area which may be expected to play an important role in a married woman's decision to return to school. as well as in determining the magnitude of the difficulties she will be confronted with, which is marital satisfaction. The present study explored the roles of sex-role identification, sex-role sterotypy were found to exert a significant influence on marital satisfaction.
Date: December 1982
Creator: Outland, Debra Ann
Partner: UNT Libraries

Multiple-Quantum NMR in Solids

Description: Time domain multiple-quantum (MQ) nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for spectral simplification and for providing new information on molecular dynamics. In this thesis, applications of MQ NMR are presented and show distinctly the advantages of this method over the conventional single-quantum NMR. Chapter 1 introduces the spin Hamiltonians, the density matrix formalism and some basic concepts of MQ NMR spectroscopy. In chapter 2, {sup 14}N double-quantum coherence is observed with high sensitivity in isotropic solution, using only the magnetization of bound protons. Spin echoes are used to obtain the homogeneous double-quantum spectrum and to suppress a large H{sub 2}O solvent signal. Chapter 3 resolves the main difficulty in observing high MQ transitions in solids. Due to the profusion of spin transitions in a solid, individual lines are unresolved. Excitation and detection of high quantum transitions by normal schemes are thus difficult. To ensure that overlapping lines add constructively and thereby to enhance sensitivity, time-reversal pulse sequences are used to generate all lines in phase. Up to 22-quantum {sup 1}H absorption in solid adamantane is observed. A time dependence study shows an increase in spin correlations as the excitation time increased. In chapter 4, a statistical theory of MQ second moments is developed for coupled spins of spin I = 1/2. The model reveals that the ratio of the average dipolar coupling to the rms value largely determines the dependence of second moments on the number of quanta. The results of this model are checked against computer-calculated and experimental second moments, and show good agreement. A simple scheme is proposed in chapter 5 for sensitivity improvement in a MQ experiment. The scheme involves acquiring all of the signal energy available in the detection period by applying pulsed spinlocking and sampling between pulses. Using this technique on polycrystalline ...
Date: November 1, 1982
Creator: Yen, Y-S.
Partner: UNT Libraries Government Documents Department

NMR Studies of Liquid Crystals and Molecules Dissolved in Liquid Crystal Solvents

Description: This thesis describes several studies in which nuclear magnetic resonance (nmr) spectroscopy has been used to probe the structure, orientation and dynamics of liquid crystal mesogens and molecules dissolved in liquid crystalline phases. In addition, a modern high field nmr spectrometer is described which has been used to perform such nmr studies. Chapter 1 introduces the quantum mechanical formalisms used throughout this thesis and briefly reviews the fundamentals of nuclear spin physics and pulsed nmr spectroscopy. First the density operator is described and a specific form for the canonical ensemble is derived. Then Clebsch-Gordon coefficients, Wigner rotation matrices, and irreducible tensor operators are reviewed. An expression for the equilibrium (Curie) magnetization is obtained and the linear response of a spin system to a strong pulsed r.f. irradiation is described. Finally, the spin interaction Hamiltonians relevant to this work are reviewed together with their truncated forms. Chapter 2 is a deuterium magnetic resonance study of two 'nom' liquid crystals which possess several low temperature mesomorphic phases. Specifically, deuterium quadrupolar echo spectroscopy is used to determine the orientation of the liquid crystal molecules in smectic phases, the changes in molecular orientation and motion that occur at smectic-smectic phase transitions, and the order of the phase transitions. For both compounds, the phase sequence is determined to be isotropic, nematic, smectic A, smectic C, smectic B{sub A}, smectic B{sub C}, and crystalline. The structure of the smectic A phase is found to be consistent with the well-known model of a two dimensional liquid in which molecules are rapidly rotating about their long axes and oriented at right angles to the plane of the layers. Molecules in the smectic C phase are found to have their long axes tilted with respect to the layer normal, and the tilt angle is temperature dependent, increasing from zero ...
Date: November 1, 1982
Creator: Drobny, G. P.
Partner: UNT Libraries Government Documents Department

Hydrogen and Deuterium NMR of Solids by Magic Angle Spinning

Description: The nuclear magnetic resonance of solids has long been characterized by very large spectral broadening which arises from internuclear dipole-dipole coupling or the nuclear electric quadrupole interaction. These couplings can obscure the smaller chemical shift interaction and make that information unavailable. Two important and difficult cases are that of hydrogen and deuterium. For example, the homonuclear dipolar broadening, HD, for hydrogen is usually several tens of kilohertz. For deuterium, HD is relatively small; however, the quadrupole interaction causes a broadening which can be hundreds of kilohertz in polycrystalline or amorphous solids. The development of cross polarization, heteronuclear radiofrequency decoupling, and coherent averaging of nuclear spin interactions has provided measurement of chemical shift tensors in solids. Recently, double quantum NMR and double quantum decoupling have led to measurement of deuterium and proton chemical shift tensors, respectively. A general problem of these experiments is the overlapping of the tensor powder pattern spectra of magnetically distinct sites which cannot be resolved. In this work, high resolution NMR of hydrogen and deuterium in solids is demonstrated. For both nuclei, the resonances are narrowed to obtain liquid-like isotropic spectra by high frequency rotation of the sample about an axis inclined at the magic angle, {beta}{sub m} = Arccos(3{sup -1/2}), with respect to the direction of the external magnetic field. Two approaches have been developed for each nucleus. For deuterium, the powder spectra were narrowed by over three orders of magnitude by magic angle rotation with precise control of {beta}. A second approach was the observation of deuterium double quantum transitions under magic angle rotation. For hydrogen, magic angle rotation alone could be applied to obtain the isotropic spectrum when H{sub D} was small. This often occurs naturally when the nuclei are semi-dilute or involved in internal motion. In the general case of large H{sub D}, ...
Date: October 1, 1982
Creator: Eckman, R. R.
Partner: UNT Libraries Government Documents Department

Supply Curves of Conserved Energy

Description: Supply curves of conserved energy provide an accounting framework that expresses the potential for energy conservation. The economic worthiness of a conservation measure is expressed in terms of the cost of conserved energy, and a measure is considered economical when the cost of conserved energy is less than the price of the energy it replaces. A supply curve of conserved energy is independent of energy prices; however, the economical reserves of conserved energy will depend on energy prices. Double-counting of energy savings and error propagation are common problems when estimating conservation potentials, but supply curves minimize these difficulties and make their consequences predictable. The sensitivity of the cost of conserved energy is examined, as are variations in the optimal investment strategy in response to changes in inputs. Guidelines are presented for predicting the consequences of such changes. The conservation supply curve concept can be applied to peak power, water, pollution, and other markets where consumers demand a service rather than a particular good.
Date: May 1, 1982
Creator: Meier, Alan Kevin
Partner: UNT Libraries Government Documents Department

Development of an Intelligence Scoring System for Human Figure Drawings

Description: This research proposed developing a multivariate intelligence scoring system for human figure drawings. The 115 subjects were drawn from clinical, medical, and noninstitutionalized populations. Initially, 72 of these drawings were analyzed for detail, proportion, perspective, and overall quality. The initial factor analysis revealed two factors corresponding roughly to the WAIS Verbal Comprehension and Perceptual Organization factors. DAP items evidencing high colinearity with FSIQ were retained. Two-stage regression of DAP items within subtests onto the WVAIS FSIQ using the data from all 115 subjects yielded the final model (R = 0.85, p < 0.0001). Cronbach's Alpha and mean item commonality were computed as estimates of internal consistency (0.95 to 0.999). A second factor analysis revealed six factors associated with intelligence in the DAP.
Date: August 1982
Creator: Hickox, Sherrie Danene
Partner: UNT Libraries

Repression-Sensitization and External-Internal Dimensions of Millon's Personality Typology

Description: In a study using 73 females and 30 male undergraduates, information on the basic dimensions of Millon's eight personality styles was obtained from correlations of the Millon Behavioral Health Inventory with Rotter's I-E scale and Byrne's R-S scale. Hypotheses predicting a significant relationship between the active-passive and repression-sensitization were generally supported. Predictions of a significant relationship between the dependent-indepenent dimension and generalized expectancy of locus of control were not supported. Implications of these findings for the efficacy of Millon's system are discussed, along with future research possibilities.
Date: August 1982
Creator: Heath, Robert Steven
Partner: UNT Libraries

Interrater Reliability of the Psychological Rating Scale for Diagnostic Classification

Description: The poor reliability of the DSM diagnostic system has been a major issue of concern for many researchers and clinicians. Standardized interview techniques and rating scales have been shown to be effective in increasing interrater reliability in diagnosis and classification. This study hypothesized that the utilization of the Psychological Rating Scale for Diagnostic Classification for assessing the problematic behaviors, symptoms, or other characteristics of an individual would increase interrater reliability, subsequently leading to higher diagnostic agreement between raters and with DSM-III classification. This hypothesis was strongly supported by high overall profile reliability and individual profile reliability. Therefore utilization of this rating scale would enhance the accuracy of diagnosis and add to the educational efforts of technical personnel and those professionals in related disciplines.
Date: December 1982
Creator: Nicolette, Myrna
Partner: UNT Libraries

Continua and Related Topics

Description: This paper is a study of continue and related metric spaces, Chapter I is an introductory chapter. Irreducible continua and noncut points are the main topics in Chapter II. The third chapter begins with a few results on locally connected spaces. These results are then used to prove results in locally connected continua. Decomposable and indecomposable continua are dealt with in Chapter IV. Totally disconnected metric spaces are studied in the beginning of Chapter V. Then we see that every compact metric space is a continuous image of the Cantor set. A continuous map from the Cantor set onto [0,1] is constructed. Also, a continuous map from [0,1] onto [0,1]x[0,1] is built, Then an order preserving homeomorphism is constructed from a metric arc onto [0,1],
Date: August 1982
Creator: Brucks, Karen M. (Karen Marie), 1957-
Partner: UNT Libraries

The Existential Concepts of Time, Death and Choice in the Poetry of Philip Larkin

Description: This thesis examines time, death, and choice in Philip Larkin's poetry, arguing that his approach to these themes is not deterministic, but existential. The argument is based on the similarity between Larkin's views and those of three existential philosophers. Larkin's view of time, like Heidegger's, is that men live not in long stretches of time, but in processions of unconnected yet similar moments. A constant underlying sadness, like Kierkegaard's despair, makes each moment reminiscent of death. Like Sartre, Larkin finds meaning in his choices, and struggles to live authentically without expectation. Although Thomas Hardy influenced Larkin, given these similarities, Larkin's poetry cannot rightly be called deterministic. It is an attempt to preserve experience for its own sake.
Date: December 1982
Creator: Paule, Elizabeth Emily
Partner: UNT Libraries

Oil Development and Social Change in Iran Since 1953

Description: This study examines the relationship between oil development and social change in Iran. The research focused on the years since 1953 examining the economic structure through the five development plans which were the major vehicles of social transformation. Within this framework the importance of oil, industrialization, land reform,, the labor force, education and health are discussed. Demographic and stratification changes are covered such as changingpopulation patterns, migration, minorities, social classes, and the distribution of wealth. Cultural and social values are then treated with emphasis on the Shah and arms, social control and social behavior. The paper concludes: oil revenues were frequently squandered without real socio-economic benefit to the masses. Economic's mismanagement and rigid social control increases pressures in society causing the 1978 revolution.
Date: August 1982
Creator: Haghshenas, Hossein
Partner: UNT Libraries

The Continued Financial Stability of Social Security

Description: The Social Security System is projected to encounter both short-term and long-term financial crises. The economic effectiveness and impacts of alternative solutions to both problems are analyzed. Government projections show the short-term deficit can be solved through interfund borrowing. Solving the long-term deficit will require the generation of new funds. All four solutions analyzed will increase unemployment, inflation, and interest rates, and decrease growth potential. A combination of increased OASI taxation and mandatory coverage is recommended as the most effective solution with the least adverse economic consequences.
Date: May 1982
Creator: Beil, Richard
Partner: UNT Libraries

The Effect of Roughness Elements on the Magnus Characteristics of Rotating Spherical Projectiles

Description: Thirty trials of each of three roughness conditions were examined. The first condition consisted of a baseball pitched so that two of the roughness elements opposed the flow. The second condition consisted of a pitched baseball with four of the roughness elements opposing the flow. The third consisted of a pitched uniformly rough sphere. The conclusions were that roughness elements increase horizontal flight deviations when a baseball rotates about a vertical axis; roughness elements on the surface of a baseball may cause a decrease in the encountered drag forces; linear velocity has a dominating effect on the trajectory of a spinning baseball; previously developed mathematical models do not adequately predict flight deviations.
Date: December 1982
Creator: Smith, Michael A. (Michael Albert)
Partner: UNT Libraries