The American Doctrine for the Use of Naval Gunfire in Support of Amphibious Landings: Myth vs. Reality in the Central Pacific of World War II.

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The United States Marine Corps and the United States Navy developed during the interwar period a doctrine that addressed the problems inherent in the substitution of naval gunfire for artillery support in an amphibious assault. The invasion of Betio Islet, Tarawa Atoll, in November of 1943 was the first test of this doctrine. It has been said many times since the war that the doctrine basically passed this test and that lessons learned at Tarawa increased the efficiency with which the Marine Corps and Navy applied the prewar doctrine during the rest of the war. An analysis of the planning and execution of naval bombardments in the Central Pacific Campaign, after the invasion of the Gilberts, does not support this claim. This analysis leads the researcher to three conclusions. First, the Japanese developed defenses against many of the effects of the gunfire support doctrine that blunted much of the force of American firepower. American planners were slow to recognize the implications of these changes and, consequently, were slow to react to them. Second, many naval commanders responsible for providing naval gunfire support for Central Pacific operations still equated tonnage of ordnance to effectiveness of bombardment, regardless of their frequent references …
Date: December 2006
Creator: Mitchener, Donald Keith
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Extemporizing Reawakened: Saxophonist Branford Marsalis's Approach to the Cadenza for Concertino da Camera for Alto Saxophone and Eleven Instruments by Jacques Ibert

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Whether provided by a composer, written out by a performer or completely improvised, the cadenza became a vehicle for performers' creativity, lyricism and technical prowess in the eighteenth and nineteenth centuries. The debate about whether to notate or improvise cadenzas, a question as old as the cadenza itself, continues today. Saxophonists have not been involved in this debate, since the instrument is a product of the mid-nineteenth century and was in its infancy just as the practice of improvising cadenzas was fading. This study documents an unprecedented, recently-recorded, improvised cadenza in one of the most significant twentieth-century saxophone works: Jacques Ibert's Concertino da Camera for Alto Saxophone and Eleven Instruments (1935). Saxophonist Branford Marsalis's neo-cadenza for Ibert's composition presents an aggregate of the twenty-first-century performer improvising a cadenza to a twentieth-century work, in a tradition that was common centuries ago. The document begins with an inquiry into improvised cadenzas, and proceeds to an examination of the performance history of the cadenza for the Concertino da Camera. Twenty professionally-recorded versions of the cadenza are presented in order to understand the performance history of the cadenza, and to place the Marsalis cadenza into context. This research culminates in a transcription and analysis …
Date: December 2006
Creator: James, Matthew T.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

A Netcentric Scientific Research Repository

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The Internet and networks in general have become essential tools for disseminating in-formation. Search engines have become the predominant means of finding information on the Web and all other data repositories, including local resources. Domain scientists regularly acquire and analyze images generated by equipment such as microscopes and cameras, resulting in complex image files that need to be managed in a convenient manner. This type of integrated environment has been recently termed a netcentric sci-entific research repository. I developed a number of data manipulation tools that allow researchers to manage their information more effectively in a netcentric environment. The specific contributions are: (1) A unique interface for management of data including files and relational databases. A wrapper for relational databases was developed so that the data can be indexed and searched using traditional search engines. This approach allows data in databases to be searched with the same interface as other data. Fur-thermore, this approach makes it easier for scientists to work with their data if they are not familiar with SQL. (2) A Web services based architecture for integrating analysis op-erations into a repository. This technique allows the system to leverage the large num-ber of existing tools by wrapping them …
Date: December 2006
Creator: Harrington, Brian
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Characterization, Properties and Applications of Novel Nanostructured Hydrogels.

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The characterization, properties and applications of the novel nanostructured microgel (nanoparticle network and microgel crystal) composed of poly-N-isopropylacrylanmide-co-allylamine (PNIPAM-co-allylamine) and PNIPAM-co-acrylic acid(AA) have been investigated. For the novel nanostructured hydrogels with the two levels of structure: the primary network inside each individual particle and the secondary network of the crosslinked nanoparticles, the new shear modulus, drug release law from hydrogel with heterogeneous structure have been studied. The successful method for calculating the volume fraction related the phase transition of colloid have been obtained. The kinetics of crystallization in an aqueous dispersion of PNIPAM particles has been explored using UV-visible transmission spectroscopy. This dissertation also includes the initial research on the melting behavior of colloidal crystals composed of PNIPAM microgels. Many new findings in this study area have never been reported before. The theoretical model for the columnar crystal growth from the top to bottom of PNIPAM microgel has been built, which explains the growth mechanism of the novel columnar hydrogel colloidal crystals. Since the unique structure of the novel nanostructured hydrogels, their properties are different with the conventional hydrogels and the hard-sphere-like system. The studies and results in this dissertation have the important significant for theoretical study and valuable application …
Date: December 2006
Creator: Tang, Shijun
Object Type: Thesis or Dissertation
System: The UNT Digital Library

An analysis of the Sonata for Trumpet and Piano by Peter Maxwell Davies, identifying the use of historical forms, and the implications for performance.

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The Sonata for Trumpet and Piano by Peter Maxwell Davies is one of his earliest works, and a notoriously difficult work to perform. While using serialism and other twentieth-century compositional techniques, this work also uses older historical forms, including sonata-allegro and sonata-rondo forms. An analysis of the work is presented, identifying the older historical forms, and considerations for performers when making decisions on how to perform the work are provided.
Date: August 2006
Creator: Adduci, Kathryn James
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Electrochemical Synthesis and Characterization of Inorganic Materials from Aqueous Solutions

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The dissertation consists of the following three sections: 1. Hydroxyapatite (HA) coatings. In this work, we deposited HA precursor films from weak basic electrolytic solution (pH= 8-9) via an electrochemical approach; the deposits were changed into crystallite coatings of hydroxyapatite by sintering at specific temperatures (600-800 ºC). The formed coatings were mainly characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). XRD patterns show well-defined peaks of HA when sintered under vacuum conditions. FTIR measurements indicate the existence of hydroxyl groups, which were confirmed by the characteristic intensity of the stretching and bending bands at ~3575 and ~630 cm-1, respectively. The SEM shows an adhesive, crack free morphology for the double-layer coating surface of the samples sintered in a vacuum furnace. 2. Silver/polymer/clay nanocomposites. Silver nanoparticles were prepared in layered clay mineral (montmorillonite)/polymer (PVP: poly (vinyl pyrrolidone)) suspension by an electrochemical approach. The silver particles formed in the bulk suspension were stabilized by the PVP and partially exfoliated clay platelets, which acted as protective colloids to prevent coagulation of silver nanoparticles together. The synthesized silver nanoparticles/montmorillonite/PVP composite was characterized and identified by XRD, SEM, and TEM (transmission electron microscopy) measurements. 3. Ce-doped lead …
Date: December 2006
Creator: Yuan, Qiuhua
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Stabat Mater by Frank Ferko, A Mosaic of Mourning: The Universality of Mothers' Grief, Ancient Texts Made Relevant by the Addition of English Interpolations

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This document examines Frank Ferko's unique setting of the ancient Latin sequence, Stabat Mater that incorporates five English interpolations dealing with the subject of parental grief over the loss of a child. The twenty Latin stanzas and five English interpolations are examined harmonically and philosophically, as two separate works. The tonal architecture of the work, outlined in two large arches built on key relationships, is explored in the body of the paper in addition to a graphic depiction and table of key centers. The interrelationship between key centers and textual considerations is examined. An extensive interview with the composer provided invaluable information regarding the creative process as it relates to the choice of English texts, compositional techniques and influences, and the stylistic musical diversity that characterizes the work. Three prominent American conductors, who have conducted significant performances Stabat Mater discussed specific problems and solutions in preparing and performing the work. Data pertaining to Stabat Mater history and other settings was gathered from reference materials, periodicals, and internet sources.
Date: May 2006
Creator: Wilson, Barbara Sue Johnston
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Modeling and reduction of gate leakage during behavioral synthesis of nanoscale CMOS circuits.

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The major sources of power dissipation in a nanometer CMOS circuit are capacitive switching, short-circuit current, static leakage and gate oxide tunneling. However, with the aggressive scaling of technology the gate oxide direct tunneling current (gate leakage) is emerging as a prominent component of power dissipation. For sub-65 nm CMOS technology where the gate oxide (SiO2) thickness is very low, the direct tunneling current is the major form of tunneling. There are two contribution parts in this thesis: analytical modeling of behavioral level components for direct tunneling current and propagation delay, and the reduction of tunneling current during behavioral synthesis. Gate oxides of multiple thicknesses are useful in reducing the gate leakage dissipation. Analytical models from first principles to calculate the tunneling current and the propagation delay of behavioral level components is presented, which are backed by BSIM4/5 models and SPICE simulations. These components are characterized for 45 nm technology and an algorithm is provided for scheduling of datapath operations such that the overall tunneling current dissipation of a datapath circuit under design is minimal. It is observed that the oxide thickness that is being considered is very low it may not remain constant during the course of fabrication. Hence …
Date: May 2006
Creator: Velagapudi, Ramakrishna
Object Type: Thesis or Dissertation
System: The UNT Digital Library

News photography image retrieval practices: Locus of control in two contexts.

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This is the first known study to explore the image retrieval preferences of news photographers and news photo editors in work contexts. Survey participants (n=102) provided opinions regarding 11 photograph searching methods. The quantitative survey data were analyzed using descriptive statistics, while content analysis was used to evaluate the qualitative survey data. In addition, news photographers and news photo editors (n=11) participated in interviews. Data from the interviews were analyzed with phenomenography. The survey data demonstrated that most participants prefer searching by events taking place in the photograph, objects that exist in the photograph, photographer-provided keywords, and relevant metadata, such as the date the picture was taken. They also prefer browsing. Respondents had mixed opinions about searching by emotions elicited in a photograph, as well as the environmental conditions represented in a photograph. Participants' lowest-rated methods included color and light, lines and shapes, and depth, shadow, or perspective. They also expressed little interest in technical information about a photograph, such as shutter speed and aperture. Interview participants' opinions about the search methods reflected the survey respondents' views. They discussed other aspects of news photography as well, including the stories told by the pictures, technical concerns about digital photography, and digital …
Date: May 2006
Creator: Neal, Diane Rasmussen
Object Type: Thesis or Dissertation
System: The UNT Digital Library

A study of computer technology use and technology leadership of Texas elementary public school principals.

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The purpose of this study was to determine Texas elementary principals' level of computer technology use and their leadership in technology integration activities as defined by the National Educational Technology Standards for Administrators (NETS*A). Additionally the study addressed technology implementation as an innovation and used the literature concerning change and innovation models to identify organizational and personal factors that might affect the level of technology use and the leadership behaviors. Survey data retrieved from 216 Texas elementary public school principals led to the formation of the following conclusions. The elementary principals involved this study reported high level computer technology use, especially with the computer tools involving communication. Principals also reported high level leadership performance to the NETS*A standards. Multiple analyses of variance (MANOVA) revealed no significant difference in mean scores between the dependent variables of computer use or leadership performance to the NETS*A standards and the independent variables including the organizational factors of school location, district spending per student, campus minority status, and campus Title I status. A regression analysis revealed a statistically significant positive relationship between principals' computer technology use and personal variables of training and perceived risk-benefit. Another regression analysis revealed a statistically significant relationship between principals' technology …
Date: May 2006
Creator: Weber, Mark J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Evaluation of dynamic and static electrical characteristics for the DY8 and YI8 process gallium diodes in comparison to the DI8 process boron diodes.

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A rectifier is an electrical device, comprising one or more semiconductor devices arranged for converting alternating current to direct current by blocking the negative or positive portion of the waveform. The purpose of this study would be to evaluate dynamic and static electrical characteristics of rectifier chips fabricated with (a) DY8 process and (b) YI8 process and compare them with the existing DI8 process rectifiers. These new rectifiers were tested to compare their performance to meet or exceed requirements of lower forward voltages, leakage currents, reverse recovery time, and greater sustainability at higher temperatures compared to diodes manufactured using boron as base (DI8 process diodes) for similar input variables.
Date: December 2006
Creator: Dhoopati, Swathi
Object Type: Thesis or Dissertation
System: The UNT Digital Library

The Leadership Path of R. Jan LeCroy

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Recent studies reveal that a considerable number of U.S. community college leaders will be retiring in the next several years. The concern is that with the large turnover, history, culture, and important lessons of leadership will be lost. The current research on the lives of presidents, their career paths, and experiences in community college leadership centers on approaches to the study of leadership at the macro level. Limited research exists in the published literature that reports and analyzes the development of individuals as community college leaders at the micro level. This results in a gap regarding understanding leadership development and strategies to prepare leaders. This study addresses this gap by providing a critical description of the leadership development of one individual who became a community college chancellor and who the literature on the community context indicates contributed to the local and national context for community colleges. Biography is gaining prominence as a legitimate and viable tool in the study of leadership. Few biographical studies currently exist which focus on leadership development in context at the micro level. This dissertation is a biographical, qualitative study of the leadership path and legacy of R. Jan LeCroy, a community college leader. The study …
Date: December 2006
Creator: Blankenbaker, Zarina A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Pursuit of Happiness: Struggling to Preserve Status Quo in Revolutionary Era Nova Scotia

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Following the Glorious Revolution in 1688, the British North American colonies interpreted Parliament's success in removing arbitrary governmental practices and establishing a balanced government as a victory for local representative government. Within these colonies, merchants secured their influence in local government in order to protect their profits and trade networks. The New England merchants that resettled in Nova Scotia in the 1750s successfully established a local government founded upon their rights as British subjects. The attempt by the British government to centralize the imperial administration in 1763 and the perceived threat of reintroducing arbitrary rule by Parliament was a direct threat to the colonial governmental system. Although Nova Scotia chose loyalism in 1775-1776, this decision did not stem from isolation or a differing political philosophy. In fact, it was their cultural and political similarities that led Nova Scotia and New England to separate paths in 1776. Nova Scotia merchants controlling the Assembly were able to confront and defeat attempts that threatened their influence in local politics and on the local economy. With the threat to their authority defeated and new markets opening for the colony, the Nova Scotia merchant class was able to preserve the status quo in local government.
Date: August 2006
Creator: Langston, Paul D.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Animals That Die

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The thesis has two parts. Part I is a critical essay entitled "Lessons Under the Amfalula." Part II is the collection of poems entitled "Animals That Die."
Date: December 2006
Creator: Campbell, Susan Maxwell
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Between the Waves: Truth-Telling, Feminism, and Silence in the Modernist Era Poetics of Laura Riding Jackson and Muriel Rukeyser

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This paper presents the lives and early feminist works of two modernist era poets, Laura Riding Jackson and Muriel Rukeyser. Despite differences of style, the two poets shared a common theme of essentialist feminism before its popularization by 1950s and 60s second wave feminists. The two poets also endured periods of poetic silence or self censorship which can be attributed to modernism, McCarthyism, and rising conservatism. Analysis of their poems helps to remedy their exclusion from the common canon.
Date: December 2006
Creator: Cain, Christina
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Bank Loans as a Financial Discipline: A Direct Agency Cost of Equity Perspective

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In a 2004 study, Harvey, Lin and Roper argue that debt makers with a commitment to monitoring can create value for outside shareholders whenever information asymmetry and agency costs are pronounced. I investigate Harvey, Lin and Roper's claim for bank loans by empirically testing the effect of information asymmetry and direct agency costs on the abnormal returns of the borrowers' stock around the announcement of bank loans. I divide my study into two main sections. The first section tests whether three proxies of the direct agency costs of equity are equally significant in measuring the direct costs associated with outside equity agency problems. I find that the asset utilization ratio proxy is the most statistically significant proxy of the direct agency costs of equity using a Chow F-test statistic. The second main section of my dissertation includes and event study and a cross-sectional analysis. The event study results document significant and positive average abnormal returns of 1.01% for the borrowers' stock on the announcement day of bank loans. In the cross sectional analysis of the borrowers' average abnormal stock returns, I find that higher quality and more reputable banks/lenders provide a reliable certification to the capital market about the low …
Date: December 2006
Creator: Hijazi, Bassem
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Neuromotor and Neurocognitive Functioning in the Prediction of Cognition, Behavior Problems, and Symptoms at Two-year Follow-up in Youth with Schizotypal Personality Disorder

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Individuals diagnosed with schizotypal personality disorder (SPD) exhibit patterns of cognitive deficits, neuromotor disturbances, and behavior problems similar to individuals with schizophrenia, and thus SPD is thought to represent one point on the continuum of schizophrenia spectrum disorders (SSDs). Deficits in behavior, cognition, and motor functioning have been implicated as childhood precursors of SSDs and appear to also vary as a function of gender and family history of psychopathology. As such, studies of youth may help in further identification of individuals at risk for SSDs. The current study examined the prospective associations between problem behaviors, neuromotor and neurocognitive functioning, as well as SSD symptoms, at baseline and 2-year follow-up in youth meeting criteria for SPD, other personality disorders, or healthy controls. The neuromotor and neurocognitive measures were able to significantly predict SSD symptoms and behavior problems above and beyond baseline predictors. Overall, the findings provide further support for the role of subcortical motor centers operating together with prefrontal cortical areas in the regulation of higher-order cognitive functioning and in producing the psychiatric features of SSDs. Significant correlations between gender, family history of schizophrenia, and history of head injury with symptoms, behavior, cognition, and motor functioning were also found and highlight …
Date: December 2006
Creator: Greher, Felicia Reynolds
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Performance appraisal impact on employee career development and performance: A longitudinal study.

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The purpose of this study was to determine the effectiveness of the implementation of an internally created performance appraisal system as well as the subjects' overall satisfaction with the implementation. The system was implemented at a major technology consulting firm in the US. The subjects of this study were three levels of employees of the firm. An employee survey conducted annually at the firm included questions relating to the implementation of the performance appraisal system. Eight years of employees' responses to three key questions were analyzed. Employees' perceptions of the appraisal feedback aiding increased performance, their belief about the implementation assisting with their career management, satisfaction with the initiative, and their understanding of the requirements for promotion were captured by this survey. Trend analysis indicates that employees at the firm perceived their career path knowledge unimproved, their understanding of promotion criteria unimproved as a result of the implementation. Employees did not indicate overall satisfaction with the implementation and the employee's belief about their skills and abilities utilization did not improve post implementation.
Date: December 2006
Creator: Bhagwat, Tanya A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Current Practices in Working With Special Education Paraeducators.

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With so many paraeducators working in special education, it is important for teachers, administrators, and researchers to know how paraeducators are being utilized, supervised, and managed in order to create the most effective programs for students with special needs. Research is needed regarding current practices in supervising paraeducators. The purposes of this study were to (a) delineate the current practices being utilized by special education teachers of students with emotional and behavioral disorders (EBD) who supervise paraeducators that work with students with EBD in the general education classroom and (b) determine how effective the supervised paraeducators perceive those practices to be. Current practices were revealed by answering the following questions: (1) According to special education teachers and paraeducators, what procedures and practices are being utilized to supervise paraeducators who work in the general education environment with students with EBD? (2) In what ways do teachers and paraeducators see these supervision practices as being effective? (3) What is the relationship between actual supervision practices and accepted best practices? There were 60 participants in all, 30 professional teachers and 30 paraeducators. All 60 participants completed a survey; of these 60, 5 teachers and 5 paraeducators were individually interviewed Findings from the study …
Date: December 2006
Creator: Asel, Crystal S.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Accuracy Variations in Human Facial Identification Based on Time of Exposure.

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This study examined the relationship between time of exposure to the human face and accurate subsequent photo line-up identification. A volunteer group of 124 undergraduate students was divided into three approximately equal sized subgroups. The three groups were then exposed to a video or a portion of a video depicting a theft. Exposure times ranged from two minutes to 30 seconds. The subjects were then given a questionnaire and shown a photo line-up of the mock perpetrator and five foils. Subjects were asked to identify the perpetrator and mark that identification on the questionnaire. Results of the experiment indicated that the longer a subject was exposed the greater the possibility of an accurate identification.
Date: December 2006
Creator: Cowle, Kenneth M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Memento mori: Concert for Violoncello and Orchestra

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Death, as a subject, has been treated extensively throughout history, both in literature as well as in music. The focus of Memento mori is to portray the inevitability of death through music. The first part of the document is an essay exploring the topic of death, its inevitability, unpredictability and the fragility of life. This section also includes a number of examples of composer's whose works have influenced the composition of the piece. The title of the work is meant to reflect that death catches up with all of us and that humans no matter how invincible they feel at certain stages of life will, eventually, succumb to death. The second part of the document is the notated orchestral score. The work is for full orchestra and solo violoncello. It is in three acts that loosely resemble three stages of life; Youth followed by life in adulthood and finally death. The work is not programmatic and the piece's formal structure varies from a traditional concerto, for although comprised of three distinct acts, there are no pauses between them. The entire work is meant to be dark and morbid and the specter of death looms throughout the piece.
Date: December 2006
Creator: Fakhouri, Fouad K.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

A Language and Visual Interface to Specify Complex Spatial Pattern Mining

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The emerging interests in spatial pattern mining leads to the demand for a flexible spatial pattern mining language, on which easy to use and understand visual pattern language could be built. It is worthwhile to define a pattern mining language called LCSPM to allow users to specify complex spatial patterns. I describe a proposed pattern mining language in this paper. A visual interface which allows users to specify the patterns visually is developed. Visual pattern queries are translated into the LCSPM language by a parser and data mining process can be triggered afterwards. The visual language is based on and goes beyond the visual language proposed in literature. I implemented a prototype system based on the open source JUMP framework.
Date: December 2006
Creator: Li, Xiaohui
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Diphosphine Ligand Substitution in H4Ru4(CO)12: X-ray Diffraction Structures and Reactivity Studies of the Diphosphine Substituted Cluster Products

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The tetraruthenium cluster H4Ru4(CO)12 has been studied for its reactivity with the unsaturated diphosphine ligands (Z)-Ph2PCH=CHPPh2, 4,5-bis (diphenylphosphino)-4-cyclopenten-1,3-dione, bis(diphenyphosphino)benzene and 1,8- bis(diphenyl phosphino)naphthalene under thermal, near-UV photolysis, and Me3NO-assisted activation. All three cluster activation methods promote loss of CO and furnish the anticipated substitution products that possess a chelating diphosphine ligand. Clusters 1, 2, 3 and 4 have been characterized in solution by IR and NMR spectroscopies, and these data are discussed with respect to the crystallographically determined structures for all new cluster compounds. The 31P NMR spectral data and the solid-state structures confirm the presence of a chelating diphosphine ligand in all four new clusters. Sealed NMR tubes containing clusters 1, 2, 3 and 4 were found to be exceeding stable towards near-UV light and temperatures up to ca. 100°C. The surprisingly robust behavior of the new clusters is contrasted with the related cluster Ru3(CO)10(bpcd) that undergoes fragmentation to the donor-acceptor compound Ru2(CO)6(bpcd) and the phosphido-bridged compound Ru2(CO)6 (µ-PPh2)[µ-C=C(PPh2)C(O)CH2C(O)] under mild conditions. The electrochemical properties have been investigated in the case of clusters 1 and 2 by cyclic voltammetry, and the findings are discussed with respect to the reported electrochemical data on the parent cluster H4Ru4(CO)12.
Date: December 2006
Creator: Kandala, Srikanth
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Comparison and Evaluation of Existing Analog Circuit Simulator using Sigma-Delta Modulator

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In the world of VLSI (very large scale integration) technology, there are many different types of circuit simulators that are used to design and predict the circuit behavior before actual fabrication of the circuit. In this thesis, I compared and evaluated existing circuit simulators by considering standard benchmark circuits. The circuit simulators which I evaluated and explored are Ngspice, Tclspice, Winspice (open source) and Spectre® (commercial). I also tested standard benchmarks using these circuit simulators and compared their outputs. The simulators are evaluated using design metrics in order to quantify their performance and identify efficient circuit simulators. In addition, I designed a sigma-delta modulator and its individual components using the analog behavioral language Verilog-A. Initially, I performed simulations of individual components of the sigma-delta modulator and later of the whole system. Finally, CMOS (complementary metal-oxide semiconductor) transistor-level circuits were designed for the differential amplifier, operational amplifier and comparator of the modulator.
Date: December 2006
Creator: Ale, Anil Kumar
Object Type: Thesis or Dissertation
System: The UNT Digital Library