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 Collection: UNT Theses and Dissertations
Persuasion in the Speeches of Senator Barry Goldwater in his 1963 Nomination Campaign
The purpose of this study is to examine what Barry Goldwater did in his 1963 speeches before Republican audiences in order to project himself as the candidate for nomination, to consider the persuasive appeals he made and their rhetorical merit. digital.library.unt.edu/ark:/67531/metadc130551/
PERT as a Management Tool
The purpose of this study is to examine the three scheduling systems available today as a management tool. The first two systems--Milestone Reporting and Line-of-Balance--are essentially Gantt charts which do not appear to meet the requirements for management control of scheduling. An investigation of PERT is made to see if it will provide additional controls necessary for proper scheduling. digital.library.unt.edu/ark:/67531/metadc108145/
Perturbation of renewal processes
Renewal theory began development in the early 1940s, as the need for it in the industrial engineering sub-discipline operations research had risen. In time, the theory found applications in many stochastic processes. In this thesis I investigated the effect of seasonal effects on Poisson and non-Poisson renewal processes in the form of perturbations. It was determined that the statistical analysis methods developed at UNT Center for Nonlinear Science can be used to detect the effects of seasonality on the data obtained from Poisson/non-Poisson renewal systems. It is proved that a perturbed Poisson process can serve as a paradigmatic model for a case where seasonality is correlated to the noise and that diffusion entropy method can be utilized in revealing this relation. A renewal model making a connection with the stochastic resonance phenomena is used to analyze a previous neurological experiment, and it was shown that under the effect of a nonlinear perturbation, a non-Poisson system statistics may make a transition and end up in the of Poisson basin of statistics. I determine that nonlinear perturbation of the power index for a complex system will lead to a change in the complexity characteristics of the system, i.e., the system will reach a new form of complexity. digital.library.unt.edu/ark:/67531/metadc6140/
Pessimism in Three Major English Poets of the Nineteenth Century
This thesis examines the evidences of pessimism in the poetry of each poet, substantiated when possible by parallel prose writings and other critical and biographical material; and finally, it reaches tentative conclusions about the direction of the change in pessimistic outlook of three poets. digital.library.unt.edu/ark:/67531/metadc163843/
Peter Lieberson's First Piano Concerto: A Buddhist-inspired poetic vision realized through twelve-tone language, other contemporary compositional techniques, together with three recitals of works by Bach, Chopin, Mozart, Albéniz, Grieg, Ginastera and Paderecki
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The main objective of this document is to explore the life and spiritual convictions of composer Peter Lieberson, and the creation of his Piano Concerto. Lieberson is a sought after composer who has won many awards and commissions. His works have been premiered and performed by some of the best musical artists of the late twentieth- and early twenty-first-century, such as Peter Serkin, Emmanuel Ax, Yo-Yo Ma, and Pierre Boulez. This study is divided into six chapters. After the Introduction, a biographical summary of Peter Lieberson's life, his spiritual beliefs and compositional style is presented. Chapter II contains background information on the Piano Concerto, along with biographical sketches of Peter Serkin, for whom the work was written, and Seiji Ozawa, music director of the Boston Symphony Orchestra and conductor of both the premier performance and Serkin's recording of the piece. Chapter III is a selective survey of the compositional techniques used in Lieberson's Concerto, in terms of the application of twelve-tone theory and the resulting octatonic, pentatonic, and whole-tone scales. Chapter IV introduces a general overview of the influence of Buddhism as a source of inspiration in the Piano Concerto. Chapter V examines aspects of performance practice issues. Chapter VI provides conclusions. The aim of this study is to further establish Peter Lieberson's stature as an important modern American composer. It is hoped that this study will encourage further research and interest in his works. digital.library.unt.edu/ark:/67531/metadc3175/
Pets and the level of loneliness in community dwelling older adults.
Loneliness is a significant problem for older adults and can lead to negative health and social outcomes. Having a companion pet is beginning to be recognized as a way loneliness can be reduced for older persons. The purpose of this descriptive study was to determine the effect of pets on the level of loneliness in persons 60 years old or older who live alone and independently in a large metropolitan community in the North Central Texas area. Using a non-random snowball sample of older individuals (N = 252), who met the study criteria, each subject was administered the researcher-developed demographic data survey instrument containing the following variables: (a) pets - having a pet/wanting a pet, (b) age, (c) gender, (d) marital status, (e) living alone, (f) losses within the last six months, (g) interactions with family members, (h) interactions with others outside of the family, (i) highest educational level achieved, (j) employment or volunteer involvement in the community, (k) religious participation, and (l) self perceived health status. The UCLA Loneliness Scale Version 3 was used to obtain the loneliness scores. Prediction of loneliness and relationship with the independent variables was tested using frequency, correlation, analysis of variance (ANOVA), and multivariate analysis using ordinary least-squares (OLS) regression analysis. The findings from this study showed that those older adults living alone who did not have a pet but would like to have a companion pet had higher levels of loneliness (p<0.05). Other findings suggested that older adults' loneliness was less if they had moderate religious participation and interactions with others (p< 0.05). Future studies are needed to examine the effects that pets have on feelings of loneliness and the ability of older individuals to cope effectively with those feelings. digital.library.unt.edu/ark:/67531/metadc5493/
The Pettis Integral and Operator Theory
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Let (Ω, Σ, µ) be a finite measure space and X, a Banach space with continuous dual X*. A scalarly measurable function f: Ω→X is Dunford integrable if for each x* X*, x*f L1(µ). Define the operator Tf. X* → L1(µ) by T(x*) = x*f. Then f is Pettis integrable if and only if this operator is weak*-to-weak continuous. This paper begins with an overview of this function. Work by Robert Huff and Gunnar Stefansson on the operator Tf motivates much of this paper. Conditions that make Tf weak*-to-weak continuous are generalized to weak*-to­weak continuous operators on dual spaces. For instance, if Tf is weakly compact and if there exists a separable subspace D X such that for each x* X*, x*f = x*fχDµ-a.e, then f is Pettis integrable. This nation is generalized to bounded operators T: X* → Y. To say that T is determined by D means that if x*| D = 0, then T (x*) = 0. Determining subspaces are used to help prove certain facts about operators on dual spaces. Attention is given to finding determining subspaces far a given T: X* → Y. The kernel of T and the adjoint T* of T are used to construct determining subspaces for T. For example, if T*(Y*) ∩ X is weak* dense in T*(Y*), then T is determined by T*(Y*) ∩ X. Also if ker(T) is weak* closed in X*, then the annihilator of ker(T) (in X) is the unique minimal determining subspace for T. digital.library.unt.edu/ark:/67531/metadc2844/
The Phantom Menace: the F-4 in Air Combat in Vietnam
The F-4 Phantom II was the United States' primary air superiority fighter aircraft during the Vietnam War. This airplane epitomized American airpower doctrine during the early Cold War, which diminished the role of air-to-air combat and the air superiority mission. As a result, the F-4 struggled against the Soviet MiG fighters used by the North Vietnamese Air Force. By the end of the Rolling Thunder bombing campaign in 1968, the Phantom traded kills with MiGs at a nearly one-to-one ratio, the worst air combat performance in American history. The aircraft also regularly failed to protect American bombing formations from MiG attacks. A bombing halt from 1968 to 1972 provided a chance for American planners to evaluate their performance and make changes. The Navy began training pilots specifically for air combat, creating the Navy Fighter Weapons School known as "Top Gun" for this purpose. The Air Force instead focused on technological innovation and upgrades to their equipment. The resumption of bombing and air combat in the 1972 Linebacker campaigns proved that the Navy's training practices were effective, while the Air Force's technology changes were not, with kill ratios becoming worse. However, the last three months of the campaign introduced an American ground radar system that proved more effective than Top Gun in improving air-to-air combat performance. By the end of the Vietnam War, the Air Force and Navy overcame the inherent problems with the Phantom, which were mostly of their own making. digital.library.unt.edu/ark:/67531/metadc283785/
Phase Separation and Second Phase Precipitation in Beta Titanium Alloys
The current understanding of the atomic scale phenomenon associated with the influence of beta phase instabilities on the evolution of microstructure in titanium alloys is limited due to their complex nature. Such beta phase instabilities include phase separation and precipitation of nano-scale omega and alpha phases in the beta matrix. The initial part of the present study focuses on omega precipitation within the beta matrix of model binary titanium molybdenum (Ti-Mo) alloys. Direct atomic scale observation of pre-transition omega-like embryos in quenched alloys, using aberration-corrected high resolution scanning transmission electron microscopy and atom probe tomography (APT) was compared and contrasted with the results of first principles computations performed using the Vienna ab initio simulation package (VASP) to present a novel mechanism of these special class of phase transformation. Thereafter the beta phase separation and subsequent alpha phase nucleation in a Ti-Mo-Al ternary alloy was investigated by coupling in-situ high energy synchrotron x-ray diffraction with ex-situ characterization studies performed using aberration corrected transmission electron microscopy and APT to develop a deeper understanding of the mechanism of transformation. Subsequently the formation of the omega phase in the presence of simultaneous development of compositional phase separation within the beta matrix phase of a Ti-10V-6Cu (wt%) alloy during continuous cooling has been investigated using a combination of transmission electron microscopy and atom probe tomography. The results of these investigations provided novel insights into the mechanisms of solid-state transformations in metallic systems by capturing the earliest stages of nucleation at atomic to near atomic spatial and compositional resolution. digital.library.unt.edu/ark:/67531/metadc67975/
Phase Shift Determination for Elastic Potential Scattering, Using the IBM 360-50 Computer
The primary objective of this paper is to present a computerized method for the extraction of phase shifts from an angular distribution. This was accomplished using a least squares curve fitting routine. digital.library.unt.edu/ark:/67531/metadc131381/
A Phenomenological Inquiry of Media Literacy of Middle School Students Enrolled in a North Texas Middle School.
This dissertation investigated the media literacy experiences of middle school students enrolled in a Texas school. The literature review suggested that middle school students may be overlooked as a distinct population in media literacy research. The primary guiding questions for this inquiry were (1) How is media literacy exhibited by middle school students within a formal school context? (2) How does an elective film and media class impact middle school students' media literacy? And (3) How do middle grade students' responses to media correspond with theoretical models for media literacy? The phenomenological research methodology included a reflective analysis of students' textual responses to non-print media clips (N=24) and a reflective analysis of follow-up personal interviews with a smaller group of middle school participants (n=5). A questionnaire completed by participants provided descriptive statistics about the sample group. Additionally, theoretical models of media literacy were used to evaluate participants' media responses in relation to theoretical constructs for media literacy. The findings resulted in 11 emergent themes which can be used to further discourse about media literacy and its role in middle school curriculum. The dissertation includes implications for educators based upon the emergent themes, as well as recommendations for further research. digital.library.unt.edu/ark:/67531/metadc9744/
Phenomenology and Northrop Frye's Anatomy of Criticism
This thesis discusses the principles of phenomenology as well as the critical theory and interrelation with the Anatomy of Criticism. digital.library.unt.edu/ark:/67531/metadc131035/
The Philosophical Basis of Nazism
The purpose of this study is to examine the work of a number of prominent German philosophers to determine the philosophical basis of Nazism, if it is granted that there is such a basis. digital.library.unt.edu/ark:/67531/metadc75520/
The Philosophical Beliefs and Practices of the Sherman Elementary Teachers
The purpose of this study was to find what the philosophies and actual practices of the Sherman elementary teachers are; and how they practice or do not practice their philosophical concepts. digital.library.unt.edu/ark:/67531/metadc70351/
Philosophical Ideas in Five Plays by Jean-Paul Sartre
The drama of Jean-Paul Sartre is primarily an investigation into the meaning of the human condition. The question of primary concern is: What does it mean to be a human being? Through his drama, Sartre reveals the nature of the existential situation. This thesis looks at five plays of Sartre and discusses the philosophical ideas in each. digital.library.unt.edu/ark:/67531/metadc130956/
Philosophical Implications on Trombone Performance and Pedagogy in Andre Lafosse's Curriculum at the Paris Conservatory
During his tenure as the professor of trombone at the Paris Conservatory, Andre Lafosse wrote the Traite de Pedagogie du Trombone a Coulisse addressing trombone pedagogy that was to be studied in conjunction with his method and etude books, Methode Complete de Trombone and Vade Mecum du Tromboniste. The pedagogic philosophy reflects Lafosse's own experiences as an orchestral musician in France in the early 20th century. Lafosse designed and used his treatise to prepare students to be effective teachers after their graduation from the Conservatory. The scope of preparation for Lafosse's trombone class, however, was limited. He did not attempt to provide a text or tutor that would prepare trombonists for any career in music: Lafosse was primarily concerned with orchestral trombone playing, as reflected in musical exercises, instrument designation, and repertoire references. Solo performance skills are also explained at length in his treatise, and Lafosse includes his own solo transcriptions in the curriculum. This emphasis placed on performing as a soloist appears to oppose Lafosse's implied preference for orchestral performance. Throughout his career as a trombone professor Andre Lafosse compiled and wrote music that emphasized elements of trombone technique based on the French solo and orchestral repertoire. His primary concern as a teacher was developing the skills for an orchestral career in France, but his method was to use exercises that focused on certain technical aspects of trombone performance. The exercises and etudes chosen were all influenced by French music regarding the skills deemed important by Lafosse (i.e. those required by the French orchestral and solo repertoire) and the acoustic design of the trombone in France in the early 20th century. Considering the holistic context of Lafosse'ss role at the Paris Conservatory, Lafosse's curriculum and methodology should be deemed appropriately designed for the best interest of the students. In the following pages the implications of Lafosse's philosophy will be explored in order to understand the basis for his ideas, and his pedagogic approach will be evaluated in the context of the mid 20th century. The purpose of these endeavors is to discover Lafosse's reasoning and its appropriateness within a synchronic context. digital.library.unt.edu/ark:/67531/metadc4780/
Philosophical Irrationalism and Italian Fascism
The purpose of this work will be to trace the development from responsible scholasticism to irrational political violence, and to locate the various sources from which the intellectual acceptance of anti-humanitarian violence spring forth. digital.library.unt.edu/ark:/67531/metadc130698/
A Philosophy for Two-year Occupational Programs in Public Junior College Curricula
The problem of this study is the development of a philosophy for two-year occupational programs in public junior college business curricula. digital.library.unt.edu/ark:/67531/metadc164485/
Philosophy in The Forsyte Saga
A study has been made of (1) the various philosophies of idealism and materialism, (2) the effects of these philosophies upon the life and thought of England in the nineteenth and twentieth centuries, and (3) the demonstration of these philosophies in John Galsworthy's The Forsyte Saga with a view to indicating the trends and tendencies in the philosophy of England which have helped to shape the personal and national life of the British people of today. digital.library.unt.edu/ark:/67531/metadc75450/
The Philosophy of Henry Fielding as Expressed in his Novel, Tom Jones
This thesis examines the philosophy of Henry Fielding as expressed in his novel, Tom Jones as it relates to the prevailing philosophical thought of eighteenth-century England. digital.library.unt.edu/ark:/67531/metadc70292/
The Philosophy of the Activity Movement
The problem of this research is to analyze the philosophy of the activity movement in the United States from a sociological point of view. Specifically, the purpose of the study is to discover whether or not the activity movement grew out of the social conditions of the times and was designed to meet the staggering problems of social development and reconstruction in America. digital.library.unt.edu/ark:/67531/metadc70307/
Phosphatides of Atypical Mycobacteria
The purpose of this investigation was to extract, separate, partially characterize and compare the individual phospholipids of the atypical mycobacteria. digital.library.unt.edu/ark:/67531/metadc163925/
Phosphorescent Emissions of Coinage Metal-Phosphine Complexes: Theory and Photophysics
The major topics discussed are all relevant to the bright phosphorescent emissions of coinage metal complexes (Cu(I), Ag(I) and Au(I)) with an explanation of the theoretical background, computational results and ongoing work on the application in materials and optoelectronic devices. Density functional computations have been performed on the majority of the discussed complexes and determined that the most significant distortion that occurs in Au(I)-phosphine complexes is a near and beyond a T-shape within the P-Au-P angle when the complexes are photoexcited to the lowest phosphorescent excited state. The large distortion is experimentally qualified with the large Stokes' shift that occurs between the excitation and emission spectra and can be as large as 18 000 cm-1 for the neutral Au(I) complexes. The excited state distortion has been thoroughly investigated and it is determined that not only is it pertinent to the efficient luminescence but also for the tunability in the emission. The factors that affect tunability have been determined to be electronics, sterics, rigidity of solution and temperature. The luminescent shifts determined from varying these parameters have been described systematically and have revealed emission colors that span the entire visible spectrum. These astounding features that have been discovered within studies of coinage metal phosphorescent complexes are an asset to applications ranging from materials development to electronics. digital.library.unt.edu/ark:/67531/metadc12200/
Phosphorus Metabolism in Atypical Mycobacteria
The design for this study was tri-phasic: 1) to establish growth time patterns for each group of atypical mycobacteria, 2) to demonstrate the dynamic state of phosphorus in the various fractions by determining its incorporation and turnover, 3) to determine quantitatively the amount of phosphorus in each fraction. digital.library.unt.edu/ark:/67531/metadc130704/
Phosphorus Retention and Fractionation in Masonry Sand and Light Weight Expanded Shale Used as Substrate in a Subsurface Flow Wetland
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Constructed wetlands are considered an inefficient technology for long-term phosphorus (P) removal. The P retention effectiveness of subsurface wetlands can be improved by using appropriate substrates. The objectives of this study were to: (i) use sorption isotherms to estimate the P sorption capacity of the two materials, masonry sand and light weight expanded shale; (ii) describe dissolved P removal in small (2.7 m3) subsurface flow wetlands; (iii) quantify the forms of P retained by the substrates in the pilot cells; and (iv) use resulting data to assess the technical and economic feasibility of the most promising system to remove P. The P sorption capacity of masonry sand and expanded shale, as determined with Langmuir isotherms, was 60 mg/kg and 971 mg/kg respectively. In the pilot cells receiving secondarily treated wastewater, cells containing expanded shale retained a greater proportion of the incoming P (50.8 percent) than cells containing masonry sand (14.5 percent). After a year of operation, samples were analyzed for total P (TP) and total inorganic P (TIP). Subsamples were fractionated into labile-P, Fe+Al-bound P, humic-P, Ca+Mg-bound P, and residual-P. Means and standard deviations of TP retained by the expanded shale and masonry sand were 349 + 169 and 11.9 + 18.6 mg/kg respectively. The largest forms of P retained by the expanded shale pilot cells were Fe+Al- bound P (108 mg/kg), followed by labile-P (46.7 mg/kg) and humic-P (39.8). Increases in the P forms of masonry sand were greatest in labile-P (7.5 mg/kg). The cost of an expanded shale wetland is within the range of costs conventional technologies for P removal. Accurate cost comparisons are dependent upon expansion capacity of the system under consideration. Materials with a high P sorption capacity also have potential for enhancing P removal in other constructed wetland applications such as stormwater wetlands and wetlands for treating agricultural runoff. digital.library.unt.edu/ark:/67531/metadc3183/
The Photo-Alkylation of C4 Hydocarbons
A study of the photo-alkylation of C4 hydrocarbons. digital.library.unt.edu/ark:/67531/metadc53390/
The Photo-Chemical Reactions of Isopentane
This thesis describes an experiment in the ultraviolet absorption of hydrocarbons. digital.library.unt.edu/ark:/67531/metadc70362/
Photoactivatable Quantum Dots in Super-Resolution Microscopy of Muscle
Super-resolution 3D imaging was achieved using newly synthesized photoactivatable quantum dot (PAQ dot) probes. Quantum dots were modified with a novel quencher system to make them photoactivatable. The unique properties of these PAQ dots enable single-fluorophore localization in three dimensions using a confocal microscopy optical sectioning method. Myosin and tropomyosin of rabbit myofibrilar bundles were specifically labeled with the newly synthesized PAQ dot. A sufficient number of single quantum dots were photoactivated, localized and reduced to their centroid and then reconstructed to a super-resolution image. The acquired super-resolution image shows a lateral and an axial sub-diffraction resolution and demonstrates ultrafine striations with widths less than 70 nm that are not evident by conventional confocal microscopy. The striations appear to be related to nebulin thin filament binding protein. This newly developed imaging system is cutting edge for its high resolution and localization as well its simplicity and convenience. digital.library.unt.edu/ark:/67531/metadc33133/
Photochemical and Photophysical Properties of Gold(I) Complexes and Phosphorescence Sensitization of Organic Luminophores
Two major topics that involve synthetic strategies to enhance the phosphorescence of organic and inorganic luminophores have been investigated. The first topic involves, the photophysical and photochemical properties of the gold (I) complexes LAuIX (L = CO, RNC where R = alkyl or aryl group; X = halide or pseudohalide), which have been investigated and found to exhibit Au-centered phosphorescence and tunable photochemical reactivity. The investigations have shown a clear relationship between the luminescence energies and association modes. We have also demonstrated for the first time that aurophilic bonding and the ligand p-acceptance can sensitize the photoreactivity of Au(I) complexes. The second topic involves conventional organic fluorophores (arenes), which are made to exhibit room-temperature phosphorescence that originates from spin-orbit coupling owing to either an external or internal heavy atom effect in systematically designed systems that contain d10 metals. Facial complexation of polycyclic arenes to tris[{m-(3,4,5,6-tetrafluorophenylene)}mercury(II)], C18F12Hg3 (1) results in crystalline adducts that exhibit bright RGB (red-green-blue) phosphorescence bands at room temperature. This arene-centered phosphorescence is always accompanied by a reduction of the triplet excited state lifetime due to its sensitization by accelerating the radiative instead of the non-radiative decay. The results of both topics are significant for rational design of efficient metal and arene-centered phosphors for molecular light emitting diodes in addition to the fundamental novelties in inorganic chemistry and molecular spectroscopy. digital.library.unt.edu/ark:/67531/metadc5375/
The Photochemical Reactions of 2,7-dimethyloctane
This thesis is a study of the photochemical reactions of 2,7-dimethyloctane. digital.library.unt.edu/ark:/67531/metadc130312/
Photochemistry of Isopropyl Alcohol
This study discusses the effects of the photochemistry of isopropyl alcohol. digital.library.unt.edu/ark:/67531/metadc107916/
Photoelectric Emission Measurements for CVD Grown Polycrystalline Diamond Films
We examined CVD grown polycrystalline diamond films having different methane concentrations to detect defects and study the possible correlation between the methane concentration used during the growth process and the defect density. SEM and Raman results show that the amorphous and sp2 carbon content of the films increases with methane concentration. Furthermore, photoelectric emission from diamond is confirmed to be a two-photon process, hence the electrons are emitted from normally unoccupied states. We found that the photoelectric yield, for our samples, decreases with the increase in methane concentration. This trend can be accounted for in two different ways: either the types of defects observed in this experiment decrease in density as the methane concentration increases; or, the defect density stays the same or increases, but the increase in methane concentration leads to an increase in the electron affinity, which reduces the overall photoelectric yield. digital.library.unt.edu/ark:/67531/metadc2199/
Photographic metaphors: A multiple case study of second language teachers' experiences using the acquisition model.
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The purpose of this study was to examine and document second language teachers' perceptions of their implementation of a meaning-making approach, known as the Acquisition Model, to second language instruction. Of particular focus were the concerns and strategies the second language teachers experienced when changing their pedagogical practice from mechanical to meaning making. The main research question, which guided this study, was: "What is the 'lived experience' of L2 teachers as they implement an innovative pedagogy to teach a second language?" The researcher addressed this research question through Max van Manen's (1990) six step phenomenological method, "Researching Lived Experience" and image-based research techniques (i.e., photo elicitation and reflexive photography). In addition, the researcher also created and applied an innovative data collection technique, which she called Collaborative Imagery. Findings from this study generated various implications in the areas of second language education, curricular change, teacher reflection, image-based research, and educational research. digital.library.unt.edu/ark:/67531/metadc5229/
The Photolysis of Ethyllithium and Triethylaluminum
The majority of interest in organolithium and organoaluminum compounds has centered around their potency as polymerization catalysts. digital.library.unt.edu/ark:/67531/metadc164375/
Photophysical properties of pyrene, 2,7 diazapyrene and 1,3-bis(β-naphthyl)propane.
The luminescence properties of Van Der Waals' dimers and clusters of pyrene and diazapyrene have been investigated. Excimers, dimeric species which are associative in an excited electronic state and dissociative in their ground state, have long been established and play an important role in many areas of photochemistry. My work here focuses on the luminescence and absorption properties of ground state dimers/aggregates, which are less understood, and allows further characterization of the ground state and excited state association of these aromatic molecules. digital.library.unt.edu/ark:/67531/metadc3999/
Photophysical studies of silver(I), platinum(II), palladium(II), and nickel(II) complexes and their use in electronic devices.
This dissertation deals with two major topics that involve spectroscopic studies of (a) divalent group 10 metals and (b) silver(I)-phosphine complexes. The scope of the work involved the delineation of the electronic structure of these complexes in different environments and their use in electronic devices. The first topic is a look at the luminescence of tetrahedral silver(I)-phosphine complexes. Broad unstructured emissions with large Stokes shifts were found for these complexes. Computational analysis of the singlet and triplet state geometries suggests that this emission is due to a Jahn-Teller type distortion. The second topic represents the major thrust of this research, which is an investigation into the electronic structure of M(diimine)X2 (M= Pt(II), Pd(II), or Ni(II); X = dichloro, or dithiolate ligands) complexes and their interactions with an electron acceptor or Lewis acid. Chapter 3 assesses the use of some of these complexes in dye sensitized solar cells (DSSCs); it is shown that these complexes may lead to a viable alternative to the more expensive ruthenium-based dyes that are being implemented now. Chapter 4 is an investigation into donor/acceptor pairs involving this class of complexes, which serves as a feasibility test for the use of these complexes in organic photo-voltaics (OPVs) and thin-film field-effect transistors (OTFTs). The mixing of a donor Pt molecule with an electron deficient nitrofluorenone gives rise to new absorption bands in the NIR region. Computational studies of one of the solids suggest that these complexes may have metallic behavior. Chapter 5 demonstrates association in solution, previously unobserved, for Pt(diimine)Cl2 complexes. This chapter is an investigation into the effects of the association mode for this class of complexes on the absorption and emission properties. One of the complexes was used as the emitter in organic light emitting diodes (OLEDs). The results of this study show that these complexes have tunable absorption and emission energies that are concentration dependant. The concentration dependence of the absorption and emission energies is utilized in the OLED device where association enhances the performance. digital.library.unt.edu/ark:/67531/metadc5165/
Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation
Copper(I) complexes have been studied through both experimental and computational means in the presented work. Overall, the work focuses on photophysical and photochemical properties of copper(I) complexes. Photophysical and photochemical properties are found to be dependent on the geometries of the copper(I) complexes. One of the geometric properties that are important for both photochemical and photophysical properties is coordination number. Coordination numbers have been observed to be dependent on both ligand size and recrystallization conditions. The complexes geometric structure, as well as the electronic effects of the coordination ligands, is shown both computationally as well as experimentally to affect the emission energies. Two-coordinate complexes are seen to have only weak emission at liquid nitrogen temperature (77 K), while at room temperature (298 K) the two-coordinate complexes are not observed to be luminescent. Three-coordinate complexes are observed to be luminescent at liquid nitrogen temperature as well as at room temperature. The three-coordinate complexes have a Y-shaped ground (S0) state that distorts towards a T-shape upon photoexcitation to the lowest lying phosphorescent state (T1). The geometric distortion is tunable by size of the coordinating ligand. Luminescence is controllable by limiting the amount of non-radiative emission. One manner by which non-radiative emission is controlled is the amount of geometric distortion that occurs as the complex undergoes photoexcitation. Bulky ligands allow for less distortion than smaller ligands, leading to higher emission energies (blue shifted energies) with higher quantum efficiency. Tuning emission and increasing quantum efficiencies can be used to create highly efficient, white emitting materials for use in white OLEDS. digital.library.unt.edu/ark:/67531/metadc84199/
Photoreactivation Studies on Azotobacter vinelandii ATCC 12837
This thesis was written to study photoreactivation in different physiological conditions of the vegetative cell as well as the photoreactivation of the two morphological states of the Azotobacter cell: the vegetative cell and the cyst. digital.library.unt.edu/ark:/67531/metadc163932/
The Phototropic Properties of Lactuca Ludoviciana (Nutt.) DC. and Silphium Laciniatum L.
This paper deals with certain phases of phototropic properties of two exceptional plants, the pertinent behavior of each being decidedly individualistic and in remarkable contrast to that of herbaceous plants in general. The prickly lettuce, Lactuca ludoviciana (Nutt.) DC. and the rosinweed, Silphium laciniatum L., two common Denton County, Texas, plants, have been selected for this study. digital.library.unt.edu/ark:/67531/metadc75308/
Physical activity and its association with selected dietary behaviors
This study examined the association between level of physical activity and changes in dietary behaviors of 3,945 employees after a 10-week work-site physical activity program. Fifty-seven percent of the participants met the CDC/ACSM standard for physical activity sufficient for a health benefit. Physical activity was not significantly related to increased fruit and vegetable consumption, decreased dietary fat and calorie intake, and participants acquiring new nutrition skills. Physical activity was negatively associated with increased food label awareness. Participants who exercised sufficient for a health benefit were less likely to increase their food label awareness. Physical activity and dietary behaviors are generally not associated. Interventions to improve these behaviors should be behavior-specific. digital.library.unt.edu/ark:/67531/metadc2910/
A Physical and Chemical Investigation of Eagle Mountain Lake with Reference to Biological Productivity
The purpose of this investigation is to attempt by correlation of chemical-physical factors to ascertain if any one of the necessary features might act as a factor limiting growth and reproduction of either plants or animals. The body of water used in this investigation is Eagle Mountain Lake, a reservoirs approximately five years of age. digital.library.unt.edu/ark:/67531/metadc29930/
The Physical, Chemical, and Biological Factors Contributing to Algae Blooms in Fresh-Water Reservoirs
The purpose of this investigation is to attempt to relate the distribution and periodicity of the plankton to the variations in the biological, chemical, and physical factors. digital.library.unt.edu/ark:/67531/metadc83493/
Physical Education as an Element in the Personal and Social Readjustment of the Problem Child in Gladewater, Texas
This study of the readjustment of problem children was undertaken as an integral part of the physical education program of the city schools of Gladewater, Texas, to determine if physical education in itself is, or can become, a positive factor in reshaping the lives of such children. digital.library.unt.edu/ark:/67531/metadc75444/
Physical Gesture, Spatialization, Form and Transformation in Watershed I/IV, for Solo Percussion and Real-time Computer Spatialization, by Roger Reynolds
Watershed I/IV, for Solo Percussion and Real-time Computer Spatialization was composed in 1995 by Pulitzer prize-winning composer Roger Reynolds. This work is a 25-minute choreographed music drama for one multiple-percussionist, in which Reynolds incorporates the musical transformation of percussion instrument families, the physical gestures of the performer, and the spatialization of processed sounds around the audience. This dissertation addresses several aspects of Watershed, which include: the expressive intent and extra-musical concepts; the formal organization, and several non-musical tools that Reynolds utilized in designing the piece (e.g. logarithmically derived sequences); the primary musical motives; the instrument setup and how the resulting physical gestures contribute to the musical intent; and the real-time computer spatialization. Throughout the document, specific musical passages are demonstrated with notated musical examples and embedded video/audio clips. In addition, transcripts of my interviews with composer Roger Reynolds, percussionist Steven Schick (premiere performer of Watershed) and engineer/technician Greg Dixon (engineer for my performances of Watershed IV) are also included. digital.library.unt.edu/ark:/67531/metadc12153/
Physical-Layer Network Coding for MIMO Systems
The future wireless communication systems are required to meet the growing demands of reliability, bandwidth capacity, and mobility. However, as corruptions such as fading effects, thermal noise, are present in the channel, the occurrence of errors is unavoidable. Motivated by this, the work in this dissertation attempts to improve the system performance by way of exploiting schemes which statistically reduce the error rate, and in turn boost the system throughput. The network can be studied using a simplified model, the two-way relay channel, where two parties exchange messages via the assistance of a relay in between. In such scenarios, this dissertation performs theoretical analysis of the system, and derives closed-form and upper bound expressions of the error probability. These theoretical measurements are potentially helpful references for the practical system design. Additionally, several novel transmission methods including block relaying, permutation modulations for the physical-layer network coding, are proposed and discussed. Numerical simulation results are presented to support the validity of the conclusions. digital.library.unt.edu/ark:/67531/metadc68065/
Physical Map between Marker 8O7 and 146O17 on the Medicago truncatula Linkage Group 1 that Contains the NIP Gene
The Medicago truncatula NIP gene is located on M. truncatula Linkage Group 1. Informative recombinants showed crossovers that localize the NIP gene between markers 146O17 and 23C16D. Marker 164N9 co-segregates with the NIP gene, and the location of marker 164N9 is between markers 146O17 and 23C16D. Based upon data from the Medicago genome sequencing project, a subset of the model legume Medicago truncatula bacterial artificial chromosomes (BACs) were used to create a physical map on the DNA in this genetic internal. BACs near the potential NIP gene location near marker 164N9 were identified, and used in experiments to predict the physical map by a BAC-by-BAC strategy. Using marker 164N9 as a center point, and chromosome walking outward, the physical map toward markers 146O17 and 23C16D was built. The chromosome walk consisted of a virtual walk, made with existing sequence of BACs from the Medicago genome project, hybridizations to filters containing BAC DNA, and PCR reactions to confirm that predicted overlapping BACs contained DNA that yielded similar PCR products. In addition, the primers which are made for physical mapping via PCR could be good genetic markers helpful in discovering the location of the NIP gene. As a result of efforts repotted here, gap in physical map between marker 164N9 and 146O17 was closed. digital.library.unt.edu/ark:/67531/metadc5152/
Physical Motivation and Methods of Solution of Classical Partial Differential Equations
We consider three classical equations that are important examples of parabolic, elliptic, and hyperbolic partial differential equations, namely, the heat equation, the Laplace's equation, and the wave equation. We derive them from physical principles, explore methods of finding solutions, and make observations about their applications. digital.library.unt.edu/ark:/67531/metadc277898/
The Physical, Social and Scholastic Attainments of Forty-Two Athletes and Forty-Two Non-Athletes in the High School, Bonham, Texas
The purpose of this study was to make a comparison of the mental, the physical, and the social attainments of forty-two athletes and forty-two non-athletes during a nine-months period in the Senior High School in Bonham, Texas. digital.library.unt.edu/ark:/67531/metadc83426/
A Physiological Age-Grading System for Female Hydrellia pakistanae Deonier (Diptera: Ephydridae)
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Conflicting opinions about the effectiveness of H. pakistanae as a biological control agent for hydrilla prompt researchers to find a method for assessing the fly's success. Developing a physiological age-grading system for the fly using ovarian morphology to detect changes in reproductive activity is useful for evaluating reproductive status of the fly in field populations. Changes in the appearance of follicular relics in ovaries with oviposition provide a reliable method to estimate fecundity. Characteristics of follicular relics were used to develop a system with eight physiological age classes, three nulliparous and five parous. Changes that occur in the fat body were used to assist in classification of nulliparous females or those with low egg counts. digital.library.unt.edu/ark:/67531/metadc3280/
Physiological and Verbal Responses to Erotic Visual Stimuli in a Female Population
In recent years, there has been a growing acceptance of sexual behavior as a legitimate area of research. An impetus for research utilizing erotic visual stimuli was supplied by the Presidential appointment of the Commission on Obscenity and Pornography (1963). Research into the effects of erotic visual stimuli has typically employed male subjects (Neiger, 1966). The paucity of adequate research has not been a deterrent to the formulation of strong opinions regarding the nature of female sexuality. The present research has focused on female responses to visual representations of the nude male figure. digital.library.unt.edu/ark:/67531/metadc131584/