UNT Theses and Dissertations - 305 Matching Results

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Americans Who Would Not Wait: The American Legion of the Canadian Expeditionary Force, 1915-1917

Description: This dissertation examines the five battalions of the Canadian Expeditionary Force designated as the American Legion. Authorized in Canada between 1915 and 1917, these units were formed to recruit volunteers from the United States to serve in the Canadian Overseas Contingent during the First World War. This work reviews the organization of Canada’s militia and the history of Anglo-American relations before examining the Canadian war effort, the formation of the American Legion, the background of its men, and the diplomatic, political, and constitutional questions that it raised. Much of the research focuses on the internal documents of its individual battalions (the 97th, 211th, 212th, 213th and 237th) and the papers of Reverend Charles Bullock now housed at the Public Archives of Canada. Documentation for the diplomatic furor the American Legion caused comes largely through the published diplomatic documents, British Foreign Office records held at the Public Record Office at Kew, and United States Department of State files at the National Archives at College Park, Maryland. The most useful sources for American Legion correspondence are the Beaverbrook papers held at the House of Lords Record Office, the papers of Canadian Prime Minister Sir Robert Laird Borden, and those of the Governor-General, the Duke of Connaught found in the Public Archives of Canada. During its brief existence the American Legion precipitated diplomatic and political problems in the United States, the United Kingdom, and the Dominion of Canada. Among the issues raised by the controversy surrounding the American Legion were: the relationship between the dominion government in Canada and the British government; the structural problems of imperial communications; the rise of a Canadian national identity and the desire for greater autonomy; and, the nature of citizenship and expatriation. This dissertation is also a long overdue account of the thousands of United States citizens ...
Date: August 2012
Creator: Smylie, Eric Paul
Partner: UNT Libraries

Between Comancheros and Comanchería: a History of Fort Bascom, New Mexico

Description: In 1863, Fort Bascom was built along the Canadian River in the Eroded Plains of Territorial New Mexico. Its unique location placed it between the Comanches of Texas and the Comancheros of the Sangre de Cristo Mountains. This post was situated within Comanchería during the height of the United States Army's war against the Southern Plains Indians, yet it has garnered little attention. This study broadens the scholarly understanding of how the United States Army gained control of the Southwest by examining the role Fort Bascom played in this mission. This includes an exploration of the Canadian River Valley environment, an examination of the economic relationship that existed between the Southern Plains Indians and the mountain people of New Mexico, and an account of the daily life of soldiers posted to Fort Bascom. This dissertation thus provides an environmental and cultural history of the Canadian River Valley in New Mexico, a social history of the men stationed at Fort Bascom, and proof that the post played a key role in the Army's efforts to gain control of the Southern Plains Indians. This study argues that Fort Bascom should be recognized as Texas' northern-most frontier fort. Its men were closer to the Comanche homeland than any Texas post of the period. Its records clearly show that the Army used Fort Bascom as a key forward base of operations against Comanches and Kiowas. An examination of Bascom's post returns, daily patrols, and major expeditions allows its history to provide a useful perspective on the nineteenth-century American Southwest.
Date: August 2012
Creator: Blackshear, James Bailey
Partner: UNT Libraries

Challenge the Silence

Description: This collection of personal essays about incest, abuse, and depression explores the lasting effects of an invisible childhood. The essays follow the protagonist from the age of five to her early twenties. Her brother, at a young age, becomes sexually abusive of her and her sisters, and her parents fail to protect their daughters. The family is divided as the older girls strive to defend their little sisters, while their parents attempt to excuse their son. When her brother is finally sent away, the protagonist is left to salvage what remains of her relationships with her parents.
Date: August 2012
Creator: Peterson, Erica
Partner: UNT Libraries

Child Rescue As Survival Resistance: Hidden Children in Nazi-occupied Western Europe

Description: The phenomenon of rescue organizations that devoted themselves specifically to hiding and saving Jewish children appeared throughout Nazi-occupied Western Europe (France, Belgium, and the Netherlands). Jewish and non-Jewish rescuers risked their lives to save thousands of children from extermination. This dissertation adds to the historiographical understanding of Holocaust resistance by analyzing the efforts of these child rescue organizations as a form of “survival resistance.” Researching the key aspects of traditional resistance (conscious intent, extensive organization, and effective turn-out) demonstrates that, while child rescue did not present armed resistance, it still was a form of active resistance against the Nazi Final Solution. By looking at rescuers’ testimonies and archival sources (from Yad Vashem, United States Holocaust Memorial Museum, Centre de documentation juive contemporaine, and Kazerne Dossin), this dissertation first outlines the extensive organization and intent of Jewish rescue groups, such as the Oeuvre de Secours aux Enfants (OSE) and Comité de défense des Juifs (CDJ), in France, Belgium, and the Netherlands. The second part looks at rescue organization and intent by Catholic, Protestant, and humanitarian groups. The dissertation concludes by discussing the effectiveness of organized child rescue. In the end, the rescue groups saved thousands of children and proofs that Child rescue in Nazi-occupied Western Europe was a valid--not to mention heroic--form of survival resistance.
Date: August 2012
Creator: Decoster, Charlotte Marie-Cecile Marguerite
Partner: UNT Libraries

Data Compression Using a Multi-residue System (Mrs)

Description: This work presents a novel technique for data compression based on multi-residue number systems. The basic theorem is that an under-determined system of congruences could be solved to accomplish data compression for a signal satisfying continuity of its information content and bounded in peak-to -peak amplitude by the product of relatively prime moduli,. This thesis investigates this property and presents quantitative results along with MATLAB codes. Chapter 1 is introductory in nature and Chapter 2 deals in more detail with the basic theorem. Chapter 3 explicitly mentions the assumptions made and chapter 4 shows alternative solutions to the Chinese remainder theorem. Chapter 5 explains the experiments in detail whose results are mentioned in chapter 6. Chapter 7 concludes with a summary and suggestions for future work.
Date: August 2012
Creator: Melaedavattil Jaganathan, Jyothy
Partner: UNT Libraries

Design, Synthesis and Screening of Homoleptic and Heteroleptic Platinum(ii) Pyridylazolate Complexes for N-type Semiconducting and Light-emitting Devices

Description: A series of heteroleptic and homoleptic platinum(II) complexes has been synthesized and characterized towards their use in thin film devices such as organic light-emitting diodes (OLEDs) and organic thin film transistors (OTFTs). Pyridylpyrazolate- and pyridyltetrazolate-containing ligands were selected due to their structural rigidity and ease of functionalization. Single-crystal x-ray diffraction studies of two selected heteroleptic complexes show strong aggregation with preferential stacking into vertical columns with a varying degree of overlap of the neighboring square planar molecular units. It is shown that the close proximity of the molecules to one another in the stack increases semiconducting character, phosphorescence quantum yields, and shorter radiative lifetimes. The potential for these materials towards incorporation into high-efficiency doping free white OLEDs (DFW-OLEDs) for solid-state lighting and display applications has been realized and will be expanded upon by present and future embodiments of materials in this thesis.
Date: August 2012
Creator: Oswald, Iain William Herbert
Partner: UNT Libraries

The Enemy of My Enemy Is What, Exactly? the British Flanders Expedition of 1793 and Coalition Diplomacy

Description: The British entered the War of the First Coalition against Revolutionary France in 1793 diplomatically isolated and militarily unprepared for a major war. Nonetheless, a French attack on the Dutch Republic in February 1793 forced the British to dispatch a small expeditionary force to defend their ally. Throughout the Flanders campaign of 1793, the British expeditionary force served London as a tool to end British isolation and enlist Austrian commitment to securing British war objectives. The 1793 Flanders campaign and the Allied war effort in general have received little attention from historians, and they generally receive dismissive condemnation in general histories of the French Revolutionary Wars. This thesis examines the British participation in the 1793 Flanders campaign a broader diplomatic context through the published correspondence of relevant Allied military and political leaders. Traditional accounts of this campaign present a narrative of defeat and condemn the Allies for their failure to achieve in 1793 the accomplishments of the sixth coalition twenty years later. Such a perspective obscures a clear understanding of the reasons for Allied actions. This thesis seeks to correct this distortion by critically analyzing the relationship between British diplomacy within the Coalition and operations in Flanders. Unable to achieve victory on their own strength, the British used their expeditionary force in Flanders as diplomatic leverage to impose their objectives on the other powers at war with France.
Date: August 2012
Creator: Jarrett, Nathaniel W.
Partner: UNT Libraries

Irony, Humor, and Ontological Relationality in Literature

Description: The purpose of this dissertation is to investigate ontological relationality in literary theory and criticism by critically reflecting on modern theories of literature and by practically examining the literary texts of Geoffrey Chaucer, William Shakespeare, and Oscar Wilde. Traditional studies of literary texts have been oriented toward interpretative or hermeneutic methodologies, focusing on an independent and individual subject in literature. Instead, I explore how relational ontology uncovers the interactive structures interposed between the author, the text, and the audience by examining the system of how the author's creative positioning provokes the reader's reaction through the text. In Chapter I, I critically inquire into modern literary theories of "irony" in Romanticism, New Criticism, and Deconstructionism to show how they tend to disregard the dynamic dimension of interactive relationships between different literary subjects. Chapter II scrutinizes Wilde's humor in An Ideal Husband (1895) and The Importance of Being Earnest (1895) in order to reveal the ontological relationships triggered by a creative positioning. In chapter III, I examine Chaucer's The Canterbury Tales (c. 1400) and the laughter in "The Miller's Tale" in particular, to examine the ethical and aesthetic dimensions of its interactive relationships. In Chapter IV, I explore Much Ado About Nothing (1598-99), Othello (1603-4), and The Winter's Tale (1609-11) so as to show how artistic positioning creatively constructs a relational system of dynamic interactions to circulate social ideals and values. In so doing, this dissertation is aimed at revealing the aesthetic values of literature and the objective scope of literary discourse rather than providing yet another analytical paradigm dependent primarily on a single literary subject. Thus, the ontological study is proposed as an alternative, yet primary, dimension of literary criticism and theoretical practice.
Date: August 2012
Creator: Kim, Soon Bae
Partner: UNT Libraries

José Antonio Gómez´s Versos Para Órgano (Section I): a Practical Guide for Performance

Description: José Antonio Gómez is an important figure in Mexican music history and his works are considered representative of the beginning of Mexico´s Independent era. Some musicians are familiar with Gómez´s choral output but his organ music is rarely considered. Due to the lack of an edition of Gómez´s Versets for Organ, a practical guide was found needed to aid its performance. This study is based on performance, analysis, and direct work on the only known source for it. The first chapter, Introduction, presents the argument for an edited version of the first part of the manuscript as a performance guide. The second provides biographical information on the composer. The third chapter discusses the background for the original performance of the Versets for Organ. Chapter 4 provides performance considerations for the works. The edition of the manuscript is included in chapter 5.
Date: August 2012
Creator: Carrasco Curíntzita, Laura A.
Partner: UNT Libraries

Motivation and Resilience in Art Education: Insight and Inspiration From the Lives and Careers of Two Taiwanese College Art Teachers

Description: This narrative study explores how two Taiwanese college art teachers’ lives and teaching experiences illustrate the ways they cultivate resilience and motivation to sustain professional commitments amidst challenges in their teaching careers. I use the life story interview as my methodology and a three-dimensional space approach to code and analyze my data to retell their stories about how resilience and motivation have guided them as they negotiated dilemmas in teaching. The participants’ stories demonstrate that in order to be motivated, teachers must satisfy their basic needs, which, in the language of Maslow’s need theory, include secure income, safety, love and belonging, respect, and personal accomplishment. To be resilient, art teachers need to facilitate self-efficacy as an essential belief to face challenges, and they also must gain support from family members, students, school administrators, and fellow members of professional organizations as external support resources. This study also illuminates the significance of international educational exchanges, the teaching knowledge constructed through layers of life and professional experience, and the importance of creating dialogue to address teachers’ challenges. Recommendations for future study include exploring further the relationship between motivation and resilience, specifying how gender difference affects the ways participants tell their stories, investigating how teachers in diverse cultural and geographical settings develop motivation and resilience, considering how teachers construct career-affirming memories from both positive and negative life experiences, and exploring uses of social media to engage a broader audience, sharing participants’ stories without the limitations of time and space.
Date: August 2012
Creator: Chang, Ya-Ping
Partner: UNT Libraries

Practical Astronomy

Description: This dissertation is a collection of poems preceded by a critical preface. The preface considers Anthony’s Hecht’s long poem, “The Venetian Vespers,” and the ways in which the temporally unsettled situation of the poem’s speaker parallels a problem facing narrative-meditative poets. The preface is divided into two main sections that explore divisions of this larger conflict. The first discusses the origins and effects of the speaker’s uprootedness in time, and the ways in which he tries to both combat and embrace this dislocation by temporarily losing himself in the immediacy of observing visual art. In this section I connect the dilemma of the speaker, who wishes to escape his memory by focusing outwards, to the dilemma of a representational poet who, despite his position towards the past, must necessarily confront or recollect memories and emotions in order to create authentic descriptions or characters. The second section focuses on the production and appreciation of artistic works (both visual and literary) and how the meaning, production and appreciation of beauty are inseparable from its existence within the physical limits of time. Here I discuss the significance of Hecht’s character who is surrounded with beauty yet describes himself as a person who only observes and does not create anything. Through this character, I argue that Hecht reveals a fundamental conflict that exists between artistic creation and chronological time, and that his poem embodies a particular and paradoxical view of beauty that resonates deeply with the motivations and struggles of writing poems.
Date: August 2012
Creator: Woodard, Chelsea S.
Partner: UNT Libraries

A Revolution in Warfare? the Army of the Sambre and Meuse and the 1794 Fleurus Campaign

Description: During the War of the First Coalition, the Army of the Sambre and Meuse, commanded by Jean-Baptiste Jourdan, played the decisive role against Coalition forces in the Low Countries. Created in June 1794, the army defeated the Allies at the battle of Second Fleurus on 26 June 1794 and commenced the Coalition’s retreat to the Rhine River. At the end of the year, Jourdan led the army to winter quarters along the left bank of the Rhine and achieved France’s historically momentous “natural frontier.” Despite its historical significance, the Army of the Sambre and Meuse has suffered from scant historical attention. Based largely on archival research, this thesis provides a detailed examination of the army’s performance during the Fleurus campaign. In addition, this thesis pursues several broader themes. A detailed study of the Sambre and Meuse Army provides insight into institutional military change during the late eighteenth century. While historians traditionally argue that the French Revolution inaugurated an attendant “revolution in military affairs,” this thesis presents evidence of evolutionary changes and continuities. Another important theme is the question of the combat effectiveness of French field armies during the Revolutionary epoch. Although historians typically present the French armies as unique and superior to their Old Regime opponents, this thesis demonstrates the effective parity between the armies of Revolutionary France and the Old Regime on the battlefield.
Date: August 2012
Creator: Hayworth, Jordan R.
Partner: UNT Libraries

Set for Life: a Novel

Description: This collection of six chapters is an excerpt from a novel based on the book of Job, as told through the viewpoint of a contemporary woman from Texas. A preface exploring the act of starting over, fictionally and creatively, precedes the chapters.
Date: August 2012
Creator: Coleman, Britta
Partner: UNT Libraries

Social Networking, Workplace, and Entertainment Literacies: the Out-of-school Literate Lives of Newcomer Latina/o Adolescents

Description: Studies indicate that Latina/o immigrant youth engage in a wide range of sophisticated literacy practices outside of school that are often transnational, crossing various linguistic, cultural, and social spaces. Technology has further afforded immigrant youth the opportunity to develop transnational capabilities which are rare in the mainstream population, yet needed in the 21st century of global connectedness. However, Latino immigrant youth drop out of school at disproportional rates, suggesting that their literacy practices are not recognized or valued by the educational system. Using a New Literacy Studies perspective that recognizes multiple literacies that are meaningful within their sociocultural traditions, this collective case study investigated the range, form, and purpose of the out-of-school literacies of four Latina/o adolescent English Learners who are new arrivals. The qualitative methodology employed constructivist interviews, digital and actual artifacts, and observations. Findings demonstrated that the most prevalent out-of-school literacies the participants practice take place on the social networking site of Facebook, in their workplaces, and through the entertainment media sources of music and television. A cross-case analysis suggests that the literacy practices in these spaces have unique and purposeful roles for the individuals that allow them to connect to their home countries and maintain their Latina/o identities. Additionally, the participants use their out-of-school literacy practices to acquire English, support themselves, and establish a place to succeed. The five aforementioned spaces that their Facebook, workplace, and entertainment literacy practices fill are virtually absent from their in-school literacies. This study suggests literacy pedagogy and research must not continue to impose a narrow monolingual, monocultural, monoliterate, and monomodal view of Latina/o immigrant students which essentially divests them of their greatest resources. Their literacy practices demonstrate that they are transnational, transcultural, emergent bilinguals who competently engage in multimodal means of communication across multiple linguistic, cultural, social, and geographic borders. Educators ...
Date: August 2012
Creator: Stewart, Mary Amanda
Partner: UNT Libraries

Southern Roots, Western Foundations: the Peculiar Institution and the Livestock Industry on the Northwestern Frontier of Texas, 1846-1864

Description: This dissertation challenges Charles W. Ramsdell's needless war theory, which argued that profitable slavery would not have existed west of the 98th meridian and that slavery would have died a natural death. It uses statistical information that is mined from the county tax records to show how slave-owners on the northwestern frontier of Texas raised livestock rather than market crops, before and during the Civil War. This enterprise was so strong that it not only continued to expand throughout this period, but it also became the foundation for the recovery of the Texas economy after the war.
Date: August 2012
Creator: Liles, Deborah Marie
Partner: UNT Libraries

The Useful Arts

Description: This creative nonfiction dissertation is a series of braided narratives that chronicle the author's career as a trombonist in the John Smith Ensemble. As an amateur trombonist, the author is shocked to be hired as a professional musician for an orchestra that plays on PBS and at Carnegie Hall. She quickly realizes, however, that the job requires her to play the trombone quietly in front of an unplugged microphone while a CD recording of another, more talented trombonist is blasted out toward an unknowing audience. The job also requires the author to tour around America. The scenes of from this tour are braided with scenes wherein she reflects on her life as a professional fake musician and her past failed attempts at getting a job.
Date: August 2012
Creator: Hindman, Jessica
Partner: UNT Libraries

American Blitzkrieg: Courtney Hodges and the Advance Toward Aachen (August 1 - September 12, 1944)

Description: This is an analysis of combat operations of US First Army under the command of Courtney Hodges, between August 1 and September 12, 1944, with an emphasis upon 1st, 4th, 9th, and 30th Divisions. However, other formations are necessarily discussed in order to maintain context. Indeed, many historians have failed to emphasize the complex interdependent nature of these efforts, and the traditional narrative has been distorted by inadequate situational awareness. This study argues that the army's operations were exceedingly difficult, resulting in approximately 40,000 casualties over a six week period. Although historians claim that the Germans were essentially defeated by the end of July, and that the Allied advance was subsequently halted by logistical difficulties, the official combat records clarify that logistical shortages were a tertiary factor, as the enemy remained capable of strong resistance. Consequently, defensive efforts were the primary factor hindering the advance, in conjunction with deteriorating weather conditions, rugged terrain, and surprisingly severe traffic congestion. Although this was mobile warfare, military theorists have overestimated the effectiveness of mechanization and underestimated the potential for antitank defenses. Ultimately, this study asserts that First Army was the primary American combat formation, and historians have exaggerated the importance of George Patton's Third Army. Therefore, in order to understand an American way of war, the combat operations of First Army deserve far more attention than they have previously received. This narrative thus emphasizes forgotten battles, including: Tessy, St. Sever, Tete, Perriers, Mayenne, Ranes, Flers, Mace, Elbeuf, Mantes, Corbeil, Sevran, Mons, Cambrai, Philippeville, Dinant, and Aubel.
Date: December 2012
Creator: Rinkleff, Adam J.
Partner: UNT Libraries

Aphorismen, Capriccio, and Heptameron for Piano Solo By Jürg Baur: a Performer's Guide

Description: The purpose of this dissertation is to give instruction regarding the performance of three important piano works by Jürg Baur (1918-2010). Aphorismen, Capriccio, and Heptameron stand out as his most significant piano works both because of their length and because of their pianistic complexity. Since Baur had a successful career as both teacher and composer during his lifetime, his acclaimed works received many honors in Germany. His works can be performed by intermediate to advanced students. Intermediate students can easily offer simpler pieces like Aphorismen in competitions, while pieces like Capriccio and Heptameron better are suited to a more advanced level. Although some of his compositions are difficult to perform compared with other modern German works, Baur's music is more accessible. In the article, "Auf der Spuren der alten Zeit" Baur is quoted to state that Paul Hindemith and Bela Bartok's music influenced his own compositional ideas. However, although Baur is a modern composer, he didn't write in a totally atonal style, but rather attempted to broaden tonality. While Heptameron is atonal, Aphorismen and Capriccio give the impression of tonality, thus they are more accessible to the audience. I was fortunate enough to study Aphorismen with Baur as well as receiving advice for performance of Capriccio and some movements of Heptameron. Therefore, I gained a primary source of instruction, particularly in regards to pedal markings, rhythmic indications, voice balancing, finger suggestions, articulation markings, and tone of musical expression. In this dissertation, I include my own instructions (accepted by the composer) along with the composer's intentions.
Date: December 2012
Creator: Park, Esther
Partner: UNT Libraries

Dolores Dyer: Women's Basketball and the American Dream

Description: Dolores Dyer played from 1952-1953 for the Texas Cowgirls, a barnstorming women's basketball team that provided a form of entertainment popular throughout the United States in that era. The story of Dyer's life demonstrates how a woman could attempt to achieve the American dream—a major theme in American history—through success in athletic competition. Dyer's participation with the Texas Cowgirls also provides a look into the circumstances that limited women's participation in professional sport during the mid-twentieth century. Women's sports studies, although some are very thorough, have gaps in the research, and women's barnstorming basketball is one of the areas often overlooked. In light of this gap, this thesis relies on a variety of sources, including primary documents from unpublished collections, archived materials, and original oral histories from several members of the Texas Cowgirls team. This thesis contains analysis of the socioeconomic factors that influenced Dolores Dyer's maturation into a professional basketball player, examines what the American dream meant to her, and evaluates the extent to which she achieved it. Overall, it constructs a social history that can serve as a foundational source for further study of women in sports during the twentieth century.
Date: December 2012
Creator: Roberts, Jackie
Partner: UNT Libraries

Investigation of Novel Electrochemical Synthesis of Bioapatites and Use in Elemental Bone Analysis

Description: In this research, electrochemical methods are used to synthesize the inorganic fraction of bone, hydroxyapatite, for application in biological implants and as a calibration material for elemental analysis in human bone. Optimal conditions of electrochemically deposited uniform apatite coatings on stainless steel were investigated. Apatite is a ceramic with many different phases and compositions that have beneficial characteristics for biomedical applications. Of those phases hydroxyapatite (HA) is the most biocompatible and is the primary constituent of the inorganic material in bones. HA coatings on metals and metal alloys have the ability to bridge the growth between human tissues and implant interface, where the metal provides the strength and HA provides the needed bioactivity. The calcium apatites were electrochemically deposited using a modified simulated body fluid adjusted to pH 4-10, for 1-3 hours at varying temperature of 25-65°C while maintaining cathodic potentials of -1.0 to -1.5V. It was observed that the composition and morphology of HA coatings change during deposition by the concentration of counter ions in solution, pH, temperature, applied potential, and post-sintering. The coatings were characterized by powder x-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The precipitated powders from the experiment were also characterized, with results showing similarities to biological apatite. There is a need for quantitative elemental analysis of calcified biological matrices such as bone and teeth; however there are no suitable calibration materials commercially available for quantitative analysis. Matrix-matched standards are electrochemically synthesized for LA-ICP-MS analysis of human bone. The synthetic bioapatite is produced via a hydrothermal electrochemical process using a simulated body fluid solution to form hydroxyapatite. Additional bioapatite standards are synthesized containing trace amounts of metals. The x-ray diffraction of the synthesized standards shows an increase in cell volume for the crystal structure from 0.534 to 0.542 nm3 with the substitution of ...
Date: December 2012
Creator: DeLeon, Vallerie H.
Partner: UNT Libraries

A New Chromophoric Organic Molecule Toward Improved Molecular Optoelectronic Devices

Description: The characterization of 2,3,6,7,10,11-hexabromotriphenylene, Br6TP, is presented toward its potential use as an n-type organic semiconductor and metal-free room temperature phosphor. The crystal structure shows both anisotropic two-dimensional BrBr interactions and inter-layer ?-stacking interactions. Photophysical characteristics were evaluated using solid-state photoluminescence and diffuse reflectance spectroscopies, revealing significantly red-shifted excitations in the visible region for the yellow solid material (compared to ultraviolet absorption bands for the colorless dilute solutions). Correlation of spectral, electrochemical, and computational data suggest the presence of an n-type semiconducting behavior due to the electron-poor aromatic ring. The material shows excellent thermal stability as demonstrated by thermogravimetric analysis and infrared spectra of a thin film deposited by thermal evaporation. The potential for Br6TP and its analogues toward use in several types of photonic and electronic devices is discussed.
Date: December 2012
Creator: Halbert, Jason Paul
Partner: UNT Libraries

Nonparametric Estimation of Receiver Operating Characteristic Surfaces Via Bernstein Polynomials

Description: Receiver operating characteristic (ROC) analysis is one of the most widely used methods in evaluating the accuracy of a classification method. It is used in many areas of decision making such as radiology, cardiology, machine learning as well as many other areas of medical sciences. The dissertation proposes a novel nonparametric estimation method of the ROC surface for the three-class classification problem via Bernstein polynomials. The proposed ROC surface estimator is shown to be uniformly consistent for estimating the true ROC surface. In addition, it is shown that the map from which the proposed estimator is constructed is Hadamard differentiable. The proposed ROC surface estimator is also demonstrated to lead to the explicit expression for the estimated volume under the ROC surface . Moreover, the exact mean squared error of the volume estimator is derived and some related results for the mean integrated squared error are also obtained. To assess the performance and accuracy of the proposed ROC and volume estimators, Monte-Carlo simulations are conducted. Finally, the method is applied to the analysis of two real data sets.
Date: December 2012
Creator: Herath, Dushanthi N.
Partner: UNT Libraries

Rational Design of Metal-organic Electronic Devices: a Computational Perspective

Description: Organic and organometallic electronic materials continue to attract considerable attention among researchers due to their cost effectiveness, high flexibility, low temperature processing conditions and the continuous emergence of new semiconducting materials with tailored electronic properties. In addition, organic semiconductors can be used in a variety of important technological devices such as solar cells, field-effect transistors (FETs), flash memory, radio frequency identification (RFID) tags, light emitting diodes (LEDs), etc. However, organic materials have thus far not achieved the reliability and carrier mobility obtainable with inorganic silicon-based devices. Hence, there is a need for finding alternative electronic materials other than organic semiconductors to overcome the problems of inferior stability and performance. In this dissertation, I research the development of new transition metal based electronic materials which due to the presence of metal-metal, metal-?, and ?-? interactions may give rise to superior electronic and chemical properties versus their organic counterparts. Specifically, I performed computational modeling studies on platinum based charge transfer complexes and d10 cyclo-[M(?-L)]3 trimers (M = Ag, Au and L = monoanionic bidentate bridging (C/N~C/N) ligand). The research done is aimed to guide experimental chemists to make rational choices of metals, ligands, substituents in synthesizing novel organometallic electronic materials. Furthermore, the calculations presented here propose novel ways to tune the geometric, electronic, spectroscopic, and conduction properties in semiconducting materials. In addition to novel material development, electronic device performance can be improved by making a judicious choice of device components. I have studied the interfaces of a p-type metal-organic semiconductor viz cyclo-[Au(µ-Pz)]3 trimer with metal electrodes at atomic and surface levels. This work was aimed to guide the device engineers to choose the appropriate metal electrodes considering the chemical interactions at the interface. Additionally, the calculations performed on the interfaces provided valuable insight into binding energies, charge redistribution, change in the energy ...
Date: December 2012
Creator: Chilukuri, Bhaskar
Partner: UNT Libraries

Water-soluble Phosphors for Hypoxia Detection in Chemical and Biological Media

Description: Water-soluble Pt(II) phosphors exist predominantly for photophysical studies. However, fewer are known to be candidates for cisplatin derivatives. If such a molecule could exist, it would be efficient at not only destroying the cancerous cells which harm the body, but the destruction would also be traceable within the human body as it occurred. Herein, research accomplished in chemistry describes the photophysical properties of a water-soluble phosphor. Spectroscopically, this phosphor is unique in that it possesses a strong green emission at room temperature in aqueous media. Its emission is also sensitive to the gaseous environment. These properties have been expanded to both analytical and biological applications. Studies showing the potential use of the phosphor as a heavy metal remover from aqueous solutions have been accomplished. The removal of toxic heavy metals was indicated by the loss of emission as well as the appearance of a precipitate. The gaseous sensitivity was elicited to be used as a potential cancerous cell biomarker. In vivo studies were accomplished in a wide variety of species, including bacteria (E. coli), worms (C. elegans), small crustaceans (Artemia), and fish (D. rerio and S. ocellatus). The phosphor in question is detectable in all of the above. This fundamental research lays the foundation for further expansion into bioinorganic chemistry, and many other possible applications.
Date: December 2012
Creator: Satumtira, Nisa Tara
Partner: UNT Libraries