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A measurement of forward-backward charge asymmetry of electron-positron pairs in proton-antiproton collision at 1.8 TeV

Description: The authors present a measurement of the mass dependence of the forward-backward charge asymmetry for e{sup +}e{sup -} pairs resulting from {gamma}*/Z decays with mass M{sub ee} > 40 GeV/c{sup 2}. The Run II data sample consists of 72 pb{sup -1} of data, which was collected by the CDF detector in {bar p}p collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. The measurement is compared with predictions from the Standard Model.
Date: December 1, 2003
Creator: Veramendi, Gregory Francisco
Partner: UNT Libraries Government Documents Department
open access

Protein Structure Recognition: From Eigenvector Analysis to Structural Threading Method

Description: In this work, they try to understand the protein folding problem using pair-wise hydrophobic interaction as the dominant interaction for the protein folding process. They found a strong correlation between amino acid sequences and the corresponding native structure of the protein. Some applications of this correlation were discussed in this dissertation include the domain partition and a new structural threading method as well as the performance of this method in the CASP5 competition. In the f… more
Date: December 12, 2003
Creator: Cao, Haibo
Partner: UNT Libraries Government Documents Department
open access

Nitrogen doped zinc oxide thin film

Description: To summarize, polycrystalline ZnO thin films were grown by reactive sputtering. Nitrogen was introduced into the films by reactive sputtering in an NO{sub 2} plasma or by N{sup +} implantation. All ZnO films grown show n-type conductivity. In unintentionally doped ZnO films, the n-type conductivities are attributed to Zn{sub i}, a native shallow donor. In NO{sub 2}-grown ZnO films, the n-type conductivity is attributed to (N{sub 2}){sub O}, a shallow double donor. In NO{sub 2}-grown ZnO films, … more
Date: December 15, 2003
Creator: Li, Sonny X.
Partner: UNT Libraries Government Documents Department
open access

Optically Detected Magnetic Resonance and Thermal Activation Spectroscopy Study of Organic Semiconductors

Description: Organic electronic materials are a new class of emerging materials. Organic light emitting devices (OLEDs) are the most promising candidates for future flat panel display technologies. The photophysical characterization is the basic research step one must follow to understand this new class of materials and devices. The light emission properties are closely related to the transport properties of these materials. The objective of this dissertation is to probe the relation between transport and p… more
Date: December 12, 2003
Creator: Kim, Chang-Hwan
Partner: UNT Libraries Government Documents Department
open access

Organogermanium Chemistry: Germacyclobutanes and digermane Additions to Acetylenes

Description: This dissertation comprises two main research projects. The first project, presented in Chapter 1, involves the synthesis and thermochemistry of germacyclobutanes (germetanes). Four new germetanes (spirodigermetane, diallylgermetane, dichlorogermetane, and germacyclobutane) have been synthesized using a modified di-Grignard synthesis. Diallylgermetane is shown to be a useful starting material for obtaining other germetanes, particularly the parent germetane, germacyclobutane. The gas-phase ther… more
Date: December 12, 2003
Creator: Chubb, Andrew Michael
Partner: UNT Libraries Government Documents Department
open access

Thermal Properties of Starch From New Corn Lines as Impacted by Environment and During Line Development

Description: The objectives of this research were to further characterize exotic by adapted corn inbreds by studying the impact of environment on their starch thermal properties, and investigating the development of starch thermal properties during kernel maturation by using differential scanning calorimetry (DSC). A method to expedite identification of unusual starch thermal traits was investigated by examining five corn kernels at a time, instead of one kernel, which the previous screening methods used. C… more
Date: December 12, 2003
Creator: Lenihan, Elizabeth M.
Partner: UNT Libraries Government Documents Department
open access

Organic Light-Emitting Devices (OLEDS) and Their Optically Detected Magnetic Resonance (ODMR)

Description: Organic Light-Emitting Devices (OLEDs), both small molecular and polymeric have been studied extensively since the first efficient small molecule OLED was reported by Tang and VanSlyke in 1987. Burroughes' report on conjugated polymer-based OLEDs led to another track in OLED development. These developments have resulted in full color, highly efficient (up to {approx} 20% external efficiency 60 lm/W power efficiency for green emitters), and highly bright (> 140,000 Cd/m{sup 2} DC, {approx}2,0… more
Date: December 12, 2003
Creator: Li, Gang
Partner: UNT Libraries Government Documents Department
open access

Electromagnetic Wave Propagation in Two-Dimensional Photonic Crystals

Description: In this dissertation, they have undertaken the challenge to understand the unusual propagation properties of the photonic crystal (PC). The photonic crystal is a medium where the dielectric function is periodically modulated. These types of structures are characterized by bands and gaps. In other words, they are characterized by frequency regions where propagation is prohibited (gaps) and regions where propagation is allowed (bands). In this study they focus on two-dimensional photonic crystals… more
Date: December 12, 2003
Creator: Foteinopoulou, Stavroula
Partner: UNT Libraries Government Documents Department
open access

Quantification of Soil Physical Properties by Using X-Ray Computerized Tomography (CT) and Standard Laboratory (STD) Methods

Description: The implementation of x-ray computerized tomography (CT) on agricultural soils has been used in this research to quantify soil physical properties to be compared with standard laboratory (STD) methods. The overall research objective was to more accurately quantify soil physical properties for long-term management systems. Two field studies were conducted at Iowa State University's Northeast Research and Demonstration Farm near Nashua, IA using two different soil management strategies. The first… more
Date: December 12, 2003
Creator: Sanchez, Maria Ambert
Partner: UNT Libraries Government Documents Department
open access

Homogeneous Precipitation of Nickel Hydroxide Powders

Description: Precipitation and characterization of nickel hydroxide powders were investigated. A comprehensive precipitation model incorporating the metal ion hydrolysis, complexation and precipitation reactions was developed for the production of the powders with urea precipitation method. Model predictions on Ni{sup 2+} precipitation rate were confirmed with precipitation experiments carried out at 90 C. Experimental data and model predictions were in remarkable agreement. Uncertainty in the solubility pr… more
Date: December 12, 2003
Creator: Mavis, Bora
Partner: UNT Libraries Government Documents Department
open access

SPA-LEED Study of the Morphology and Nucleation of a Novel Growth Mode and the ''devil's staircase'' on Pb/Si(111)

Description: This thesis was developed to address the following questions for the Pb/Si(111) system: (1) Is it possible to control the nano-structure growth by changing the initial substrate; (2) is the nucleation theory applicable to the case of the 7-step growth mode; and (3) what phase or phases could be formed between coverage 6/5 ML and 4/3 ML? The first question was answered in chapter 2, different growth results were observed for different initial substrate, suggesting the possibility of controlling … more
Date: December 12, 2003
Creator: Yeh, Wang-Chi Vincent
Partner: UNT Libraries Government Documents Department
open access

Bioanalytical Applications of Real-Time ATP Imaging Via Bioluminescence

Description: The research discussed within involves the development of novel applications of real-time imaging of adenosine 5'-triphosphate (ATP). ATP was detected via bioluminescence and the firefly luciferase-catalyzed reaction of ATP and luciferin. The use of a microscope and an imaging detector allowed for spatially resolved quantitation of ATP release. Employing this method, applications in both biological and chemical systems were developed. First, the mechanism by which the compound 48/80 induces rel… more
Date: December 12, 2003
Creator: Gruenhagen, Jason Alan
Partner: UNT Libraries Government Documents Department
open access

Knowledge and attitudes of preservice teachers towards students who are gay, lesbian, bisexual, or transgendered.

Description: The study used a survey design to ascertain the levels of knowledge and attitudes of special education and non-special education preservice and inservice teachers towards students with different sexual orientations. The results of this study are based on 408 responses from preservice and inservice teachers enrolled at seven institutions of higher education within North Carolina, Virginia, and the District of Columbia offering teacher training programs in regular and/or special education. Two pr… more
Date: December 2003
Creator: Morgan, Daniel J.
Partner: UNT Libraries
open access

Cost Savings Realized Through Proper Sizing of an Excessive Instrument Air System.

Description: The purpose of this research was to determine if installing a smaller air compressor could reduce the electrical usage of a large semiconductor manufacturing plant. A 200 horsepower Atlas Copco compressor was installed with the existing 500 horsepower Ingersoll-Rand compressors. Testing was conducted during the regular manufacturing process at MEMC Southwest in Sherman, Texas. Analysis of the data found that installing the new compressor could reduce electrical consumption. The study also found… more
Date: December 2003
Creator: Condron, Ewell D.
Partner: UNT Libraries
open access

Texas Cities and the Economic Development Sales Tax

Description: Competition to lure corporations has become an enormous issue between states. Smaller communities feel unable to participate in economic development opportunities since their budgets do not provide the necessary funding. In 1979, the Texas state legislature passed the Development Corporation Act in an attempt to aid the smaller communities' quest for economic development. The Act allowed for the creation of local development corporations; however, it did not provide a sufficient funding source … more
Date: December 2003
Creator: Comer-HaGans, DeLawnia
Partner: UNT Libraries
open access

Perceptions of Parents of Postsecondary Education Students Concerning Parental Notification and Underage Alcohol Offenses

Description: Since the inception of the Higher Education Reauthorization Act of 1998 by the United States Congress, there has been limited research conducted on parental notification policies on campuses of Higher Education concerning alcohol and drug offenses committed by students. This study surveyed parents of incoming freshmen at the University of North Texas regarding their perceptions of Parental Notification policies and their perceptions of underage alcohol offenses by gender, age, ethnicity, and p… more
Date: December 2003
Creator: Clouse, Maureen McGuinness
Partner: UNT Libraries
open access

The gathering and use of information by fifth grade students with access to Palm® handhelds.

Description: Handheld computers may hold the possibility for a one-to-one computer: student ratio. The impact of the use of Palm® (Palm, Inc.) handhelds on information acquisition and use by 5th grade students in a North Texas school during a class research project was investigated. Five research questions were examined using observation, interviews, surveys, and document analysis. Are there differences in information gathering and use with the Palm between gifted, dyslexic, and regular learners? What relev… more
Date: December 2003
Creator: Peet, Martha Stuart Williamson
Partner: UNT Libraries
open access

Intelligent Memory Management Heuristics

Description: Automatic memory management is crucial in implementation of runtime systems even though it induces a significant computational overhead. In this thesis I explore the use of statistical properties of the directed graph describing the set of live data to decide between garbage collection and heap expansion in a memory management algorithm combining the dynamic array represented heaps with a mark and sweep garbage collector to enhance its performance. The sampling method predicting the density an… more
Date: December 2003
Creator: Panthulu, Pradeep
Partner: UNT Libraries
open access

Harmonization of Accounting Practices Among IAS Firms Listed in the U.S. and Its Capital Market Implications

Description: The focus of the study is on financial reporting for non-U.S. firms registered with the Securities Exchange Commission (SEC) but using International Accounting Standards (IAS). This study addresses two issues, (1) whether the comparability of financial reporting among firms using IAS in credit and equity financing jurisdictions increases over time and (2) the associated capital market implications. The motivation for the study is the SEC's ongoing assessment of IAS for possible use by non-U.S. … more
Date: December 2003
Creator: Paananen, Mari
Partner: UNT Libraries
open access

Outer Reaches of the Palindrome

Description: This work is an exploration into the palindrome, both as a literary form and an expression of infinity. The first two chapters address the fascinating manner in which the mind contextualizes fragments of speech and ludicrous grammatical implications that are spawned by the poetic structure of the palindrome (third chapter). The thesis then departs from the literary aspect of the palindrome and focuses in the fourth chapter on structural likenesses in psychology and mythology. The fifth chapter … more
Date: December 2003
Creator: McConnell, Michael Constantine
Partner: UNT Libraries
open access

Ecuadorian Children: an Investigation Into the Effects Frequenting the Street Has on the Children of Cuenca, Ecuador.

Description: The purpose of this study was to examine the effects frequenting the street had on the social-emotional development of children in Cuenca, Ecuador. While the study sought to discover who these children were, it primarily observed the levels of trust these children felt in the various contexts of their lives, their level of safety, where they saw themselves in the future, what made a place feel like a home, their sense of self-esteem, and how they saw themselves contributing to their future. The… more
Date: December 2003
Creator: McBride, Rachel
Partner: UNT Libraries
open access

Negotiating Environmental Relationships: Why Language Matters to Environmental Philosophy

Description: The medium of language is important to environmental philosophy, and more specifically, to the establishment and understanding of environmental relationships. The differences between animal and human language point to our unique semantic range, which results from our neuro-linguistic process of signification. An examination of the linguistic implications of the problem of nature and the tenets of semiotics challenges the idea of a clean word to world fit. Because signs are the medium in which m… more
Date: December 2003
Creator: Martin, Vernon J.
Partner: UNT Libraries
open access

Fashion Circles

Description: Through this body of work and this paper the possibilities of using Fashion Design to express the concepts of the circle has been explored. This was done with three questions in mind: How can I use the shape of the circle as inspiration for fashion design? How can I express related words and phrases in my design? and How can I use the colors black and white to emphasize the concept of my design. To answer these questions I have created two groups of garments: one was inspired by circular object… more
Date: December 2003
Creator: Öhrn, Linda
Partner: UNT Libraries
open access

Required Counseling Provided Within a Counselor Training Program: Its Effect on Self-Awareness and the Impact of Ethical Concerns on the Experience

Description: This study examined the experience of 140 students in a counselor training program that required students to participate in 10 sessions of individual counseling during their training program in order to increase their self-awareness. Students had the option of fulfilling the requirement through being counseled either by more advanced students within the training program or by mental health professionals outside the program. Results indicated that students in both settings reported a significant… more
Date: December 2003
Creator: Oden, Kathryn A.
Partner: UNT Libraries
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