Development of a Novel Grease Resistant Functional Coatings for Paper-based Packaging and Assessment of Application by Flexographic Press

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Recent commercial developments have created a need for alternative materials and methods for imparting oil/grease resistance to paper and/or paperboard used in packaging. The performance of a novel grease resistant functional coating comprised of polyvinyl alcohol (PVA), sodium tetraborate pentahydrate (borate) and acetonedicarboxylic acid (ACDA) and the application of said coating by means of flexographic press is presented herein. Application criteria is developed, testing procedures described, and performance assessment of the developed coating materials are made. SEM images along with contact angle data suggest that coating performance is probably attributable to decreased mean pore size in conjunction with a slightly increased surface contact angle facilitated by crosslinking of PVA molecules by both borate ions and ACDA.
Date: August 2004
Creator: Brown, Robert W.
System: The UNT Digital Library

Differences in Mother and Father Perceptions, Interactions and Responses to Intervention with a Special-needs Adoptive Child.

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Parents' perceptions of their child's behavior may differ for mothers and fathers. Differences in parental perception may also be apparent in cases of special needs adoptive families with high demands of their child for time, interventions and attention. This paper examines the differences in mother-child and father-child interactions, child behavior as reported by mothers, and fathers and changes in both after participation in an intervention program. Results suggest notable differences between mothers' and fathers' parent-child interaction scores and reports of child behavior. In addition, interaction scores and behavior reports showed some correlations. Finally, there seemed to be notable differences in the trends for the Child Behavior Checklist compared to the two attachment measures (Randolph Attachment Disorder Questionnaire and Beech Brook Attachment Disorder Checklist). Several possible explanations for mother and father differences are discussed.
Date: August 2004
Creator: Meland, Angela M.
System: The UNT Digital Library

Asserting Identity in Wagner's Shadow: The Case of Engelbert Humperdinck's Königskinder (1897)

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Engelbert Humperdinck (1854-1921), who was considered a Wagnerian due to to his past work in Bayreuth and the Wagnerian traits of his Hänsel und Gretel, seems to have believed that to define himself as a composer, he had to engage somehow with that designation, whether through orthodox Wagner imitation or an assertion of his independence from Wagner's musical legacy. The latter kind of engagement can be seen in Humperdinck's Königskinder (1897), in which he developed a new kind of declamatory notation within the context of melodrama, thus fulfilling Wagnerian ideals as well as progressing beyond them. The effectiveness of Humperdinck's effort is seen in the ensuing critical reception, in which the realities of being heard as a Wagnerian composer are clarified.
Date: August 2004
Creator: Kinnett, Forest Randolph
System: The UNT Digital Library

Random growth of interfaces: Statistical analysis of single columns and detection of critical events.

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The dynamics of growth and formation of surfaces and interfaces is becoming very important for the understanding of the origin and the behavior of a wide range of natural and industrial dynamical processes. The first part of the paper is focused on the interesting field of the random growth of surfaces and interfaces, which finds application in physics, geology, biology, economics, and engineering among others. In this part it is studied the random growth of surfaces from within the perspective of a single column, namely, the fluctuation of the column height around the mean value, which is depicted as being subordinated to a standard fluctuation-dissipation process with friction g. It is argued that the main properties of Kardar-Parisi-Zhang theory are derived by identifying the distribution of return times to y(0) = 0, which is a truncated inverse power law, with the distribution of subordination times. The agreement of the theoretical prediction with the numerical treatment of the model of ballistic deposition is remarkably good, in spite of the finite size effects affecting this model. The second part of the paper deals with the efficiency of the diffusion entropy analysis (DEA) when applied to the studies of stromatolites. In this case …
Date: August 2004
Creator: Failla, Roberto
System: The UNT Digital Library

An Examination of the Relationships Between Affective Traits and Existential Life Positions

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There were two major goals of this study - to examine validity of scores for the Boholst Life Position Scale and to examine potential associations between life positions and affective traits. Two hundred seventy-seven students enrolled in undergraduate psychology classes at a large university volunteered for the study. Concurrent validity of scores for the life position scale was supported based on two compared instruments. Pearson product-moment correlations for the comparisons were -.765 and .617, both statistically significant at the p < .001 level. Factor analysis demonstrated that the scale could accurately be conceptualized as consisting of two factors - an "I" factor and a "You" factor. MANOVA, ANOVA, multiple linear regression, and canonical correlation analysis were used to examine associations between life positions and the affective traits of angry, sad, glad, social anxiety, loneliness, and satisfaction with life. Subjects were catagorized into four groups representing their life position: "I'm OK, you're OK," "I'm OK, you're not OK," "I'm not OK, you're OK," and "I'm not OK, you're not OK." A MANOVA employing life position as the independent variable with four levels and the six affective traits as the dependent variables demonstrated statistical significance (p < .001 level) and h2 was …
Date: August 2004
Creator: Wiesner, Van
System: The UNT Digital Library

Effect of Chronic Alcohol Abuse and Resistance Training on the Skeletal Muscle Androgen Receptor Concentration of Rats

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The purpose was to examine the effect of chronic alcohol abuse on the androgen receptor content (AR) in skeletal muscle, and to determine if this effect was influenced by resistance training. Thirty-four male rats (456 ± 1 g; mean ± SE) were divided into 4 groups: Sham exercise-Ethanol, Sham exercise-Normal diet, Exercise-Ethanol, and Exercise-Normal diet. Both Exercise groups underwent a 6-week "squat" resistance training protocol and both Ethanol groups received an alcohol-rich diet throughout the 6-week period. Western blot analysis showed no effect of alcohol or resistance training on the AR of the extensor digitorum longus. For the rectus femoris, alcohol caused a decline in the AR (p=0.01). This reduction was not attenuated by resistance training. The AR of the soleus was not affected by chronic alcohol abuse alone; however, the resistance training induced increase in the AR was prevented by chronic alcohol abuse (p=0.03).
Date: August 2004
Creator: Vingren, Jakob L.
System: The UNT Digital Library

Functional analysis and elimination of SIB in an olive baboon (Papio hamadryas anubis).

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Self injurious behavior (SIB), such as self-biting and head-banging, has been reported to occur in approximately 10% of captive, individually housed primates (Novak, Kinsely, Jorgensen, and Hazen, 1998). Accounts of the causes of SIB range from environmental to physiological. However, to date, no researchers have investigated the possible influence of social consequences, delivered by handlers and keepers, in the maintenance of SIB. There is only one research report showing that self-injury can be shaped in primates by the manipulation of food as a reinforcing consequence for the animal's behavior. The current study investigated the effects of social contact as potentially reinforcing consequences for the SIB displayed by an olive baboon (Papio hamadryas anubis). Results indicated that the behavior was maintained by attention from humans. As treatment, reinforcement was arranged for an appropriate alternative attention-getting behavior, resulting in increases in the appropriate alternative behavior and decreases in SIB.
Date: August 2004
Creator: Dorey, Nicole R.
System: The UNT Digital Library

Foot and/or Bicycle Patrols in Major Texas Metropolitan Police Departments

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During the last 25 years in law enforcement in the United States, there has been a universal practice of foot and/or bicycle patrols used to accomplish the goal of police patrol enforcement and the philosophy of community policing in metropolitan areas. These tactics of patrol have also been used in police departments in and around the State of Texas. This report is a research project on six major metropolitan police departments in the State of Texas, analyzing their allocation of foot and/or bicycle patrol units within their urban cities. The study assesses their early history in using these two police tactics to address criminal activity and their progression from foot patrol to bicycle patrol. The findings of this research support the proposition that major Texas police departments have adopted the practices and philosophies of other major urban police departments around the US, by using foot and/or bicycle patrols in their cities. There is evidence that major Texas police departments were using foot patrol during the early 1980s in support of community policing and gradually phased out this practice in the early 1990s to adopt the new enforcement tactic of policing on a bicycle.
Date: August 2006
Creator: Pavlik, Wayne Louis
System: The UNT Digital Library

Pathophysiology and Racial/Ethnic Disparities in the Progression of Metabolic Syndrome

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Disparities exist in the U.S. between the health status of African American and Hispanic individuals and the health status of non-Hispanic Caucasian individuals across all age groups. Those minority individuals age 55 and over are more likely to suffer from specific health disparities in areas such as diabetes, heart disease, and cancer than their white majority counterparts. Among the most common chronic disorders experienced within this age group are obesity, type II diabetes and cardiovascular disease, all three of which collectively form what has recently become known as metabolic syndrome. As of 2004, metabolic syndrome is diagnosable once criteria are clinically significant for a variety of different risk factors designated by the World Health Organization. However, like many syndromes these criteria are not stable across individuals, and leaves variability between individuals being diagnosed. It has been seen that each of the above mentioned racial/ethnic groups experience the individual risk factors at disproportionate rates, making it plausible that metabolic syndrome could be experienced in distinctly different ways depending upon racial/ethnic background. Using two nationally representative data sets, it is first largely evident that African American and Hispanic individuals are reaching higher peak rates of diabetes and cardiovascular disease much earlier in …
Date: August 2006
Creator: O'Neill, Amy E.
System: The UNT Digital Library

Cross-Cultural Adaptability of Texas Dental Hygienists and Dental Hygiene Students: A Preliminary Study

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This causal-comparative and correlational study examined cross-cultural adaptability of randomly selected licensed dental hygienists, 1995-2005 graduates, practicing in the state of Texas and first and second-year dental hygiene students attending 5 randomly selected accredited 2 and 4-year dental hygiene schools in the state of Texas. A sample of 289 individuals: 194 enrolled students and 95 licensed dental hygienists, alumni of the 5 schools, completed the 50-item Cross-Cultural Adaptability Inventory (CCAI ®) and a brief demographic survey. The purpose of this study was to determine if statistically significant differences existed among and between licensed dental hygienists and first and second-year dental hygiene students in the state of Texas on a cross-cultural adaptability measure. The study also examined relationships among and between cross-cultural adaptability scores, as measured by the CCAI, and several independent variables. The data were analyzed by using the Statistical Package of Social Sciences (SPSS 12). Eight hypotheses related to group differences and relationships among and between groups and variables were tested. The groups were compared on total CCAI scores using a t-test, and on subscale CCAI scores simultaneously using a descriptive discriminant analysis (DDA). A 3X2 MANOVA was used to compare all groups simultaneously on subscale CCAI scores. The …
Date: August 2006
Creator: Tavoc, Tabitha
System: The UNT Digital Library

A social capital perspective on IT professionals' work behavior and attitude.

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Abstract Attracting and developing information technology (IT) professionals is one of the top concerns for companies. Although much research has been conducted about the job behavior and attitudes of IT professionals over the last three decades, findings are inconclusive and contradictory. This suggests that something may be missing in how we examine this phenomenon. Most of this research is drawn from theories of motivation, very little examines the effect of social relationships on IT professionals' behavior and attitude. Yet, social capital theory suggests that job behavior and attitude may be greatly influenced by these relationships. This suggests that IT professionals' social capital warrants empirical examination. The primary research question that this dissertation addresses is how social capital affects IT professionals' work attitude and behavior including job satisfaction, organizational citizenship behavior, job performance and turnover intention. The research model in this dissertation examines the influence of three aspects of social capital on IT professionals' job attitude and work behavior: tie strength, the number of ties and the structural holes. Data were collected from 129 IT professionals from a range of jobs, organizations and industries. Results indicate that tie strength in the organization of an IT professional is positively related to job …
Date: August 2006
Creator: Zhang, Lixuan
System: The UNT Digital Library

Influence of executive function on medication adherence in neurologically impaired and non-impaired elderly.

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Medication non-compliance has become one of the most prevalent reasons for hospitalization and doctor's visits by the elderly. As the elderly population is more likely to have decreased cognitive abilities, it is suggested that neuropsychological factors, especially executive function, are more influential in medication non-compliance than once thought. This study looked at executive function performance on a traditional battery of neuropsychological tests, self-report of perceived ability to perform executive function tasks, and the newly developed Pillbox Test, a performance based IADL measure. The Pillbox Test is designed to replicate a type of medication-management specific IADL as a means to asses executive function. Standard executive function measures only tap a portion of executive function, but it is believed that the Pillbox Test incorporates all four theoretical domains of executive function. The multiple measures of executive function performance were compared in three prevalent subgroups of the elderly population (mixed neurological group, cardiac medical-control group, and healthy community-control group). Results found significant differences, where the community-control and cardiac groups outperformed the mixed neurological group on the large majority of executive function tasks. Smaller differences were also noted between the community-control and cardiac groups and between the cardiac and mixed neurological groups. Together, these …
Date: August 2006
Creator: Zartman, Andrea Leigh
System: The UNT Digital Library

English language learners: Does summer school make a difference in young children's literacy scores?

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Many school districts consider literacy and oral language as a top priority for pre-kindergarten students. In the district under study, pre-kindergarten English language learner (ELL) students are encouraged to attend a special summer school program to increase their oral language ability in English. This study compared three groups of children: ELL students attending summer school v. ELL students not attending summer school v. English speaking students not attending summer school. The students' primary reading inventory scores from the end of pre-kindergarten to the middle of kindergarten in the areas of reading, writing and oral language were compared. As expected, ELLs who attended summer school showed significant growth in oral language development from the beginning of summer school to the end of summer school. While it was hypothesized that ELL students attending summer school would show more improvement in oral language than other children over time, there was no significant difference between summer school and non-summer school children's scores by the middle of kindergarten.
Date: August 2006
Creator: Wickert, DeAnna S.
System: The UNT Digital Library

Employee empowerment: Relationships between location in the hierarchy, span of control, and industry type on perceptions of empowerment.

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The current study seeks to examine the relationships between perceptions of employee empowerment and perceptions of leadership, span of control, and industry type. Participants were gathered from an archival source employing a high school alumni e-mail group (n = 361) and a survey from 9 organizations (n = 647) and combined into a larger sample (n = 1008). The participants took Bodner's (2005) Assessment of Employee Empowerment and Assessment of Empowering Leadership instruments. Support was found to suggest that people report being less empowered than they believe that top management would report about them. Also, participants reported that their leader was less empowering than they believed top management would report about the leader. Span of control was found to impact perceptions of empowerment. Production workers reported feeling more empowered than workers in service industries. Participants did not report that leaders were more empowering if they were higher in the hierarchy (executive) than lower levels (coach, employee). Also, a respondent's position did not affect the relationship between job type and feelings of empowerment. This study suggests that the organizational design (span of control) and industry type may affect empowerment initiatives, while lower levels of the organization may view empowerment much differently …
Date: August 2006
Creator: Turner, Jon T., Jr.
System: The UNT Digital Library

Alexander Johnson's Ni' Concerto (1994) - Concerto no. 1 for Piano and Orchestra: a Discussion of Influences from Africa, Eastern and Western Europe

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In the new generation of artists emerging in South Africa, Alexander Johnson is considered the most prolific young composer of his day. In a recent review in the Pretoria News, Johnson has been praised by eminent critic Paul Boekkooi as a composer who has “an ear for the exotic and knows exactly how to bring it off....” He continued by noting that his music is “mentally engrossing, pleasurable to the senses and seems refreshingly free from dogmatic formulas." Johnson writes for musicians and the general public to equal satisfaction. His accessible compositions and catching use of melodic materials have made his writings very popular both in South Africa and abroad. During his residency in Belgrade in 1993-94, Johnson met Croatian pianist Dorian Leljak. Impressed with Johnson's compositional ideas and output, Leljak commissioned a work from Johnson for piano and orchestra. The result was the Niš Concerto, which Johnson completed in April 1994. The world premiere took place on June 23, 1994 with the Niš Philharmonic Orchestra conducted by Anatoli Nowiestski with Dorian Leljak as soloist. The Niš Concerto received its South African premiere in 1995 during a simultaneous celebration for “Europe Day” and the new democracy of the Republic of …
Date: August 2001
Creator: Malan, Petronel
System: The UNT Digital Library

Perceived Submaximal Leg Extension Forces of Young Adult Males

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The purpose was to examine actual force (AF) productions of males for accuracy during leg extensions when given a random desired force (DF) ranging from 10-90% of maximal force (MF). Thirty males ranging from 18 to 30 years of age (M = 21.99 + 3.04), who had no previous experience with the test equipment, went through 9 randomly ordered submaximal efforts followed by a maximal effort. Correlations between AF and DF were high (r > .79) and test-retest was consistent between AF (r = .87) and MF (r = .90). Participants consistently undershot DF on both test and retest from 20-90% and overshot DF only at 10%. Power functions revealed exponents of less than 1, indicating that AF grows slower then DF for both test .70 (.95 CI = .63 - .77) and retest .66 (.95 CI = .60 - .73). The results replicate a prior study by Jackson, Martin, Koziris, Ludtke, and Dishman (2001) that used incremental rather than random increases in DF.
Date: August 2001
Creator: Ludke, Andrew William
System: The UNT Digital Library

Unintended Outcomes: The Effects of an Entity's Educator Preparation Accreditation on Access to Certification for Individuals of Color

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The purpose of this dissertation was twofold. First, the study sought to determine if the Texas Academic Skills Program (TASP) Reading score predicts success on the Examination for the Certification of Educators in Texas (ExCET). Second, the study addressed the effect on individuals of color of raising the minimum TASP Reading score entrance requirement for admission to teacher preparation programs. Data were collected from the ExCET Office of a Carnegie I metropolitan university. The defined sample consisted of 961 participants who had a TASP Reading score and had taken an Elementary Comprehensive ExCET, an Elementary Professional Development ExCET or a Secondary Professional ExCET between September 1999 and January 2001. Linear Regression, Box Test, Predictive Discriminate Analysis, and frequency distribution tables were used for analyses. This investigation examined the effects of the independent variable of TASP Reading score on the performance of participants on the dependent variable, the ExCET. Four null hypotheses were tested at the .05 level of significance. The TASP Reading score was a statistically significant predictor for success on the Elementary Comprehensive ExCET, Elementary Professional Development ExCET, and the Secondary Professional Development ExCET. However, the Predictive Discriminate Analysis indicated that a TASP Reading score of 220 predicted that …
Date: August 2001
Creator: Rozell, Diann
System: The UNT Digital Library

Variations of the Hand Test with young and older adults

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To explore the influence that variations in projective stimuli might have on the respondent's ability to identify with pictorial representations of hands derived from the Hand Test (Wagner, 1961, 1983), 61 young adults (M age = 23) and 60 older adults (M age = 73) were presented with four alternate versions of hand stimuli (young male, young female, old male, and old female) in addition to the original Hand Test. Results indicated main effects for age and gender of respondent, which were primarily consistent with previous Hand Test research. Main effects for gender and age of hand stimuli (p < .05) were also found. Significant interaction effects were revealed for age of respondent by age of hand stimuli and for age of respondent by gender of hand stimuli (p < .05). These interactions resulted in the elicitation of a variety of responses to a differentiated manner than a standard set of Hand Test stimuli. A gender of respondent by gender of hand stimuli interaction effect was also found (p &lt; .05), suggesting that gender alterations of the card may also be beneficial for increasing respondent identification for some individuals. Overall, the results of variations in Hand Test stimuli, as they …
Date: August 2001
Creator: Radika, Lisa M.
System: The UNT Digital Library

Genetic Modification of Fatty Acid Profiles in Cotton

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The industrial uses of cottonseed oil are limited by its fatty acid composition. Genetic modification of cotton lipid profiles using seed-specific promoters could allow cotton growers to produce valuable new oils in the seed without adverse effects on fiber quality and yield, therefore making this crop more commercially profitable. Transgenic cotton callus harboring a diverged fatty acid desaturase gene (FADX) from Momordica charantia was characterized for production of alpha-eleostearic acid (conjugated double bonds: 18:3 D9 cis, 11 trans, 13 trans), not normally found in cotton. Gas chromatography (GC) in conjunction with mass spectrometry (MS) confirmed production of alpha-eleostearic acid in the transgenic cotton tissues. A second series of transformation experiments introduced the cotton fatty acid thioesterase B (FATB) cDNA, fused to the seed-specific oleosin promoter into cotton to promote the over-expression of FATB, to generate cotton with increased palmitate in the cottonseed. PCR amplification, as well as fatty acid analysis by gas chromatography, confirmed introduction of the FATB cDNA in transgenic tissues. Collectively, these results demonstrate the feasibility of manipulating the fatty acid composition in cotton via transgenic approaches and form the basis for continued efforts to create novel oils in cottonseed.
Date: August 2005
Creator: Rommel, Amy A.
System: The UNT Digital Library

A Critical Study of Arnold Schoenberg's Chamber Transcription of Gustav Mahler's Das Lied von der Erde

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Toward the end of his life, from 1908 to 1909, Gustav Mahler (1860-1911) composed Das Lied von der Erde (The song of the earth). This piece is a cycle of six song movements based on seven poems selected from Die chinesische Flötem - Nachdichtungen chinesischer Lyrik (The Chinese flute - free adaptation of Chinese lyric poetry) by Hans Bethge. The Chinese verse was written by Li-Po (numbers 1, 3, 4 and 5), Tchang-Tsi (number 2), and Mong-Kao-Jen and Wang-Wei (combined in number 6). Subsequently, in 1921, Arnold Schoenberg reduced the work to a simple chamber version transcription from Mahler's original massive score for full orchestra, a version completed in 1983 by Rainer Riehn. While the main melodic material in the vocal parts was maintained, the orchestral parts underwent substantial changes. This dissertation explores Mahler's reconfiguration of textual material and the setting of these texts in the orchestral medium. After consulting the various textual editions, I establish misreading and translational differences from the original Chinese through its various Western European incarnations; how and why Mahler chose the Bethge edition; what influenced his specific selection of poetry; and how these poems inform one another and the work as a whole. I also …
Date: August 2006
Creator: Sun, Ai-Kuang
System: The UNT Digital Library

An Overview and Performance Guide to Manuel Ponce's Sonata III for Solo Guitar

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Composed in 1927 and dedicated to Segovia, Ponce's Sonata III, one of the staples of the classical guitar repertoire, is the focus of this paper. To put this piece into proper perspective among Ponce's other works, biographical information leading up to the composition of the piece is presented first. Each of the three movements is then analyzed with regard to formal construction as well as harmonic and melodic language. Analysis is an important precursor to actually playing the piece, as Sonata III is a work that departs from Ponce's previous compositional style. The main portion of this paper addresses the preparation and interpretation of Sonata III. The insight gained through initial analysis of the piece is used to arrive at a musically satisfying interpretation of the work. Specific performance suggestions are included. Technical issues are addressed and possible solutions are presented. Alternate fingerings are provided to alleviate some of the common technical challenges the guitarist will encounter. A transcription and discussion of the Segovia revisions are also present. The paper concludes with general suggestions for improving performance that would be applicable to other works for guitar as well. This synthesis of biographical information, analysis, editorial options and performance suggestions, has …
Date: August 2006
Creator: Smith, Jay
System: The UNT Digital Library

Texas Cowboy as Myth: Visual Representations from the Late Twentieth Century

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The working cowboy remains part of the contemporary culture of Texas. A visual record of him appeared early in the state's history, in daguerreotypes, followed by representations in contemporary black and white as well as color photographs, film and video. Although the way of life for the Texas cowboy has changed, it remains a thriving part of the Texas economy, society, and culture. Moreover, the image of the cowboy has permeated popular culture and fine art. This paper explores what late twentieth century popular culture and fine art images of the cowboy signify, emphasizing aspects of how they signify in relation to an existing tradition of photographic representations. Using Barthes' "Myth Today," it considers how the documentary aspect of early photographic representations of cowboys is transformed in contemporary popular culture and fine art to become mythology, for example, by the exaggeration of features of dress to connote ideals allegorically.
Date: August 2006
Creator: Seaton, Melynda
System: The UNT Digital Library

Interfacial Studies of Bimetallic Corrosion in Copper/Ruthenium Systems and Silicon Surface Modification with Organic and Organometallic Chemistry

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To form Cu interconnects, dual-damascene techniques like chemical mechanical planarization (CMP) and post-CMP became inevitable for removing the "overburden" Cu and for planarizing the wafer surface. During the CMP processing, Cu interconnects and barrier metal layers experience different electrochemical interactions depending on the slurry composition, pH, and ohmic contact with adjacent metal layers that would set corrosion process. Ruthenium as a replacement of existing diffusion barrier layer will require extensive investigation to eliminate or control the corrosion process during CMP and post CMP. Bimetallic corrosion process was investigated in the ammonium citrate (a complexing agent of Cu in CMP solutions) using micro test patterns and potentiodynamic measurements. The enhanced bimetallic corrosion of copper observed is due to noble behavior of the ruthenium metal. Cu formed Cu(II)-amine and Cu(II)-citrate complexes in alkaline and acidic solutions and a corrosion mechanism has been proposed. The currently used metallization process (PVD, CVD and ALD) require ultra-high vacuum and are expensive. A novel method of Si surface metallization process is discussed that can be achieved at room temperature and does not require ultra-high vacuum. Ruthenation of Si surface through strong Si-Ru covalent bond formation is demonstrated using different ruthenium carbonyl compounds. RBS analysis accounted for …
Date: August 2006
Creator: Nalla, Praveen Reddy
System: The UNT Digital Library

Evaluation of hydrogen trapping in HfO2 high-κ dielectric thin films.

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Hafnium based high-κ dielectrics are considered potential candidates to replace SiO2 or SiON as the gate dielectric in complementary metal oxide semiconductor (CMOS) devices. Hydrogen is one of the most significant elements in semiconductor technology because of its pervasiveness in various deposition and optimization processes of electronic structures. Therefore, it is important to understand the properties and behavior of hydrogen in semiconductors with the final aim of controlling and using hydrogen to improve electronic performance of electronic structures. Trap transformations under annealing treatments in hydrogen ambient normally involve passivation of traps at thermal SiO2/Si interfaces by hydrogen. High-κ dielectric films are believed to exhibit significantly higher charge trapping affinity than SiO2. In this thesis, study of hydrogen trapping in alternate gate dielectric candidates such as HfO2 during annealing in hydrogen ambient is presented. Rutherford backscattering spectroscopy (RBS), elastic recoil detection analysis (ERDA) and nuclear reaction analysis (NRA) were used to characterize these thin dielectric materials. It was demonstrated that hydrogen trapping in bulk HfO2 is significantly reduced for pre-oxidized HfO2 prior to forming gas anneals. This strong dependence on oxygen pre-processing is believed to be due to oxygen vacancies/deficiencies and hydrogen-carbon impurity complexes that originate from organic precursors used in …
Date: August 2006
Creator: Ukirde, Vaishali
System: The UNT Digital Library