Application-Focused Investigation of Monovalent Metal Complexes for Nanoparticle Synthesis

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Over the last 20 years, there has occurred an increase in the number, scope, and impact of nanomaterials projects. By leveraging the Surface Plasmon Resonance of metallic nanoparticles for labelling, sensing, and treatment, researchers have demonstrated the versatile utility of these nanomaterials in medicine. The literature provides evidence of use of simple, well-known chemistry for nanomaterials synthesis when the focus is new applications of nanomaterials. A case in point, is the synthesis of metallic nanoparticles, whereby HAuCl4, CuCl2, Cu(acac)2, and AgNO3 are typically employed as nanoparticle precursors. Unfortunately, the use of these precursors limits the number of applications available to these materials - particularly for AuNPs in medicine, where the byproducts of nanoparticle synthesis (most often surface-adsorbed reductants, toxic stabilizers, and growth directors) cause nanoparticles to fail clinical trials. Despite the several thousand publications detailing the advancements in nanoparticle therapeutics, as of 2017, there were only 50 FDA-approved nanoparticle formulations. Less than 10 were based on metallic nanoparticles. This is a problem because many of these nanoparticle therapeutics demonstrate potent cell killing ability and labeling of cells. A solution to this problem may be the use of weakly coordinated, monovalent metal complexes, which require only one electron to reduce them …
Date: August 2019
Creator: Kamras, Brian Leon
Object Type: Thesis or Dissertation
System: The UNT Digital Library

How the Conflict of Autonomous and Controlled Motivation Influences Sales Controls to Inside Sales Agents' Work Outcomes

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Through the use of multiple methodologies and analytical approaches, this dissertation combines (1) sales control; (2) call center service; and (3) motivational theory to extend sales control literature beyond its current state, to consider the conflicting motivational perspectives an inside sales agent has to experience. To achieve this unification, this dissertation consists of three essays intended to: (1) identify the influence of autonomous and controlled motivation on operational sales outcome controls and performance; (2) explore the influence these motivators have on sales controls and sales performance; and, (3) understand the impact of autonomous and controlled motivation on sales agent tenure.
Date: August 2019
Creator: Conde, Gonzalo R
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Turkish Gazis' (Injured Veterans) Transition into Civilian Life

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The aim of this study was to describe the dimensions of Turkish Gazis' transition to civilian life, to explore the main factors that make this process easier or more difficult, and their psychological integration, that is, specifically, satisfaction with their life. To that end, this study examined the impact of combat-related traumatic stressor (e.g., functional limitations), personal resources (social support, sense of mastery), perceived mental health on Turkish veterans' adjustment into civilian life and their psychological integration. The data was collected in Turkey in 2015 by the researcher with the help of Türkiye Harp Malulü Gaziler Şehit Dul ve Yetimler Derneği, a non-profit veteran organization. The final sample included 240 Turkish Gazis. The level of perceived transition into civilian life and veterans' life satisfaction were the dependent variables in this study. A series of ordinary least squares (OLS) regression was conducted. Hayes' PROCESS macro 3.0 was utilized to measure the direct, indirect and moderation effects of variables on transition and life satisfaction among Gazis. The results demonstrated that perceived available social support, perceived sense of mastery and mental health partially mediated the association between Gazis' functional limitations and transition into civilian life and they fully mediated the association between functional …
Date: August 2019
Creator: Celebi, Mehmet
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Method Development for Corrosion Testing of Carbon Steel and Ni-based Alloy Coatings Exposed to Gas Hydrate Formation Environments

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Gas hydrate formation and corrosion can cause serious safety and flow assurance problems in subsea environments. One aspect that has been given less attention is the corrosion behavior of materials in gas hydrate formation environment (GHFE). This work introduces a new technique/method for corrosion testing of materials exposed to low temperatures GHFEs. This technique allows pH monitoring, and control of test conditions like temperature. In this work, GHFE is defined as an environment that includes water, methanol and its degraded products in the presence of corrosive agents like CO2 and chloride salt at gas hydrate formation temperatures (GHFT). After 20 hrs immersion in CO2-saturated salinity environment at GHFT, as-deposited Ni-Mo alloy coating has the highest corrosion resistance of 33.28 kΩ cm2. The corrosion resistance dropped to 14.36 kΩ cm2 and 11.11 kΩ cm2 in the sweet low-salinity and sweet high-salinity test solutions respectively. The combined results of SEM/EDX showed that the Ni-Mo coating oxide layer broke down quicker in sweet high-salinity environment than sweet low-salinity environment. When carbon steel was immersed in a CO2-saturated high salinity environment at GHFT, there was slight overall change in corrosion rate (CR) as salt concentration increase from 3 wt% to 25 wt%. In degraded …
Date: August 2019
Creator: Ozigagu, Christopher E.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Electrochemical Deposition of Metal Organic-Modified-Ceramic Nanoparticles to Improve Corrosion and Mechanical Properties

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Corrosion is an unstoppable process that occurs spontaneously in many areas of industry, specially, oil and gas industries. Therefore, the need of developing protective coating to lower the cost of corrosion is very consistent. Among different methods, electrodeposition has been a popular method since it offer many advantages such as low cost, ability to control the surface and thickness of the coating, ability to perform at low temperature and pressure, and very convenience. Ceramic nanoparticles have been widely incorporated into metal coating and used as a protective layer to improve both corrosion and hardness properties. Diazonium synthesis was used to modify cerium oxide nanoparticles by grafting with ferrocene for use in nickel nanocomposite coating. Citric acid and citrate salt were used as stabilizing ligands for yttrium oxide and praseodymium oxide nanoparticles in nickel plating solution to prevent the formation of hydroxide, thus, higher amount of nanoparticles was able to incorporate into nanocomposite coatings. These fabricated coatings were evaluate for the corrosion and mechanical properties using many different instruments and electrochemical techniques. As modified cerium oxide, stabilized yttrium oxide or praseodymium oxide added into nickel coatings. The results showed an increase in hardness and corrosion resistance leading to the overall improvement …
Date: August 2019
Creator: Ngo, Ngan Kim
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Optimizing Production System Maintenance Policies when Cyber Threats are Considered

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In a production environment, physical and cyber-related failures become unavoidable because of the complexity of highly connected manufacturing systems and a finite equipment life cycle. The main purpose of this thesis is to investigate optimal maintenance outsourcing and replacement policies in the presence of cyber-threats, as well as policies to achieve channel coordination via cost subsidization. Although well-developed maintenance outsourcing literature has addressed many advanced and trending issues such as the costs and benefits of new technology adoptions, learning effects, forgetting effects, and systems with back-up machines, no study has looked at the effect of cyber threats on connected production systems. Besides filling this gap, this thesis addresses the most common replacement policies including preventive maintenance with minimal repairs and age replacement. The advent of the Internet of Things (IoT) has enabled the creation of "smart" manufacturing systems, However the resulting connected format makes these systems potential targets for cyber-attacks. Manufacturers have to face a difficult decision as to whether they should adopt costly security technologies or let the manufacturing systems be vulnerable to cyber-threats. This study develops a model addressing this dilemma by providing some insights into the effects of cost subsidization and installation of security systems on the …
Date: August 2019
Creator: Ta, Anh V
Object Type: Thesis or Dissertation
System: The UNT Digital Library

A Novel Two-Stage Adaptive Method for Estimating Large Covariance and Precision Matrices

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Estimating large covariance and precision (inverse covariance) matrices has become increasingly important in high dimensional statistics because of its wide applications. The estimation problem is challenging not only theoretically due to the constraint of its positive definiteness, but also computationally because of the curse of dimensionality. Many types of estimators have been proposed such as thresholding under the sparsity assumption of the target matrix, banding and tapering the sample covariance matrix. However, these estimators are not always guaranteed to be positive-definite, especially, for finite samples, and the sparsity assumption is rather restrictive. We propose a novel two-stage adaptive method based on the Cholesky decomposition of a general covariance matrix. By banding the precision matrix in the first stage and adapting the estimates to the second stage estimation, we develop a computationally efficient and statistically accurate method for estimating high dimensional precision matrices. We demonstrate the finite-sample performance of the proposed method by simulations from autoregressive, moving average, and long-range dependent processes. We illustrate its wide applicability by analyzing financial data such S&P 500 index and IBM stock returns, and electric power consumption of individual households. The theoretical properties of the proposed method are also investigated within a large class of …
Date: August 2019
Creator: Rajendran, Rajanikanth
Object Type: Thesis or Dissertation
System: The UNT Digital Library

A Global Spatial Model for Loop Pattern Fingerprints and Its Spectral Analysis

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The use of fingerprints for personal identification has been around for thousands of years (first established in ancient China and India). Fingerprint identification is based on two basic premises that the fingerprint is unique to an individual and the basic characteristics such as ridge pattern do not change over time. Despite extensive research, there are still mathematical challenges in characterization of fingerprints, matching and compression. We develop a new mathematical model in the spatial domain for globally modeling loop pattern fingerprints. Although it is based on the well-known AM-FM (amplitude modulation and frequency modulation) image representation, the model is constructed by a global mathematical function for the continuous phase and it provides a flexible parametric model for loop pattern fingerprints. In sharp contrast to the existing methods, we estimate spatial parameters from the spectral domain by combining the exact values of frequencies with their orientations perpendicular to the fingerprint ridge flow. In addition, to compress fingerprint images and test background Gaussian white noise, we propose a new method based on periodogram spacings. We obtain the joint pdf of these m-dependent random variables at Fourier frequencies and derive the asymptotic distribution of the test statistic.
Date: August 2019
Creator: Wu, Di
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Understanding the Micromechanism of Cyclic Loading Behavior of Ultrafine Grained Alloys

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In the current study, we have investigated the cyclic loading behavior of conventional as well as novel alloy system exhibiting fine and ultrafine-grained structure. While in case of conventional alloy systems (here aluminum alloy AA5024), the effect of three different grain sizes was investigated. Improvement in fatigue properties was observed with decreasing grain size. The unique microstructure produced via Friction stir processing was responsible for the improved fatigue response. Additionally, microstructures consisting of a high fraction of special boundaries within the fine and ultrafine-grained regime were also subjected to cyclic loading. The hierarchical features introduced in the eutectic high entropy alloy deflected the persistent slip bands, responsible for fatigue cracking, thus resulted in delayed crack initiation and improved fatigue life. The selective nature of fatigue was learnt in the fine grain Al0.5CoCrFeNi, where the introduction of hierarchical features did not result in improved fatigue properties. The weak links in the microstructure, while not affecting the tensile properties, got exposed during cyclic loading. Further study on the medium entropy alloy revealed the inherent reason for the improved fatigue properties. The medium entropy alloys utilized the benefit of UFG single-phase FCC matrix. The UFG matrix showed signs of transformation of FCC phase …
Date: August 2019
Creator: Shukla, Shivakant
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Ceramide Biosynthesis and NEET Proteins Impact Development, Function, and Maintenance of the Caenorhabditis elegans Germline

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I used the C. elegans genetic model to examine the role of ceramide biosynthesis (sphingolipid pathway) and iron regulation and found that each process impacts germline development and function. Using a sphingolipid specific antibody mAb15B4, I found that sphingolipids are associated with germ granules (P granules) within C. elegans and zebrafish; thus, suggesting conservation of macromolecules associated with germ granules. Phenotype analysis of ceramide biosynthesis mutants in C. elegans revealed that this pathway is essential for normal germline function in the aging adult hermaphrodite; specifically, precocious germline senescence was observed. Furthermore, I found that disruption of ceramide biosynthesis, via the hyl-2 deletion mutation, negatively impacts mAb15B4 localization at the P granules. Through genetic suppression analysis, I determined that insulin signaling and lipid biosynthesis can modulate the mAb15B4 localization to P granules. Additional, phenotype analysis showed that ceramide biosynthesis dysfunction decreased fecundity, and led to germline structure defects and uterine tumors. Through suppression analysis, I determined that modulation of the insulin signaling pathway suppressed the precocious germline senescence due to ceramide biosynthesis dysfunction. Since the presence of uterine tumors is associated with reproductive senescence I concluded that ceramide biosynthesis has a role in germline maintenance in the aging of the germline …
Date: August 2019
Creator: King, Skylar Dawn
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Phase Transformations in Refractory High Entropy Alloys

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High entropy alloys (HEAs) based on refractory elements have shown a great potential for high temperature structural applications. In particular, the ones containing Al, exhibits a microstructure similar to the γ-γ' in Ni-based superalloys. While these alloys exhibit impressive strengths at room temperature (RT) and at elevated temperatures, the continuous B2 matrix in these alloys is likely to be responsible for their brittle behavior at RT. Phase stability of five such alloys are studied by thermo-mechanical treatments and characterization techniques using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Two of these alloys showed an inverted microstructure, where the disordered BCC phase becomes continuous, and therefore, they were characterized in detail using SEM, TEM, atom probe tomography (APT) and synchrotron x-ray diffraction experiments. The phenomenon of phase inversion lead to a better combination of strength and ductility as compared to the non-inverted microstructure.To enhance the stability of B2 intermetallic phase which provides the strength when present in a BCC matrix, multicomponent B2 phase compositions stable at 1000°C in some of the above studied alloys, were melted separately. The aim was to establish a single phase B2 at 1000°C and understand the mechanical behavior of these single-phase multicomponent B2 intermetallic …
Date: August 2019
Creator: Soni, Vishal
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Dynamic Deformation and Shear Localization in Friction-Stir Processed Al0.3CoCrFeNi and Fe50Mn30Co10Cr10 High-Entropy Alloys

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High entropy alloys (HEAs) are a relatively new class of solid solution alloys that contain multiple principal elements to take advantage of their high configurational entropy, sluggish diffusion, lattice distortion, and the cocktail effect. In recent development, work hardening mechanisms known as twinning induced plasticity (TWIP) and transformation induced plasticity (TRIP) have been found active in Al0.3CoCrFeNi (molar fraction) and Fe50Mn30Co10Cr10 (at %) HEA compositions. Friction-stir processing was done to increase the mechanical properties and improve the microstructure of the alloys for the purpose of high strain rate performance. Quasi-static tensile tests as well as top-hat geometry Split-Hopkinson pressure bar tests were conducted to view the mechanical properties as well as view the microstructural evolution at dynamic strain rates. Overall, the Al0.3CoCrFeNi condition after friction-stir processing and heat treatment has proved to have the best mechanical properties, and selecting from the conditions in this study, Al0.3CoCrFeNi has better shear localization resistance.
Date: August 2019
Creator: Macdonald, Neil
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Psychological Well-Being and Family Functioning in Middle Childhood: The Unique Role of Sibling Relational Dynamics

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The current study examined associations between perceived family functioning, sibling relational dynamics, and individual's self-reported personal adjustment and internalizing problems among 8- to 11-year old children. Path analyses revealed significant direct effects between conflictual family functioning and children's psychological well-being (p < 0.05). Further, sibling conflict was found to indirectly affect these associations. Finally, significant interactions between family functioning and sibling dynamics were found suggesting that congruent relational dynamics at multiple levels of the family system had a cumulative impact on the child's well-being. Findings from the current study highlight the unique contributions of sibling relationships to the family and the child providing evidence for targeting the sibling relationship in clinical interventions and future family research.
Date: August 2019
Creator: Geerts, Ashley T.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Military and Veteran Mental Health Stigma and Help-Seeking Behaviors: Role of Leadership and Attachment

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Mental health stigma has been identified as a barrier to help-seeking in the United States. Research suggests that insecure attachment may contribute to higher mental health stigma and lower help-seeking behavior. This may be particularly salient in military personnel who tend to report higher mental health stigma than the general population. Evidence suggests that both supportive and destructive military leadership are related to service members' attitudes toward seeking help. In the current study, a sample of military service members and veterans (N = 232) completed an online survey regarding mental health stigma, military leadership experiences, attachment strategies, and mental health help-seeking behaviors. Findings indicated that destructive and supportive leadership experiences were significantly related to self and public stigma, and self-stigma mediated the relationship between destructive and supportive leadership experiences and likelihood to seek help. Attachment anxiety predicted higher self and public stigma, while attachment avoidance predicted high self-stigma but low public stigma, with high self-stigma partially mediating the relationship between attachment avoidance and help seeking.
Date: August 2019
Creator: McGuffin, James
Object Type: Thesis or Dissertation
System: The UNT Digital Library

The Effects of the IAM Workshop on Preservice Teachers' Perceptions and Attitudes on Integrating Art and Mathematics In Saudi Arabia

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This mixed-methods dissertation used an explanatory sequential design to examine art and mathematics preservice teachers' perceptions and attitudes towards integrating art and mathematics (IAM) after an IAM workshop. The conceptual framework of this study has its basis in three theoretical sources: constructivism, multiple intelligence theory, and semiotics. Each of these sources provides a conceptual lens to examine art integration in the curriculum and the teacher's role in facilitating this instructional process. Participants of this study included two sub-groups at a large university in Saudi Arabia. The first sub-group was preservice teachers of art education. The second sub-group was preservice teachers of mathematics. Quantitative and qualitative results indicated that the IAM workshop had positive impacts on art and mathematics preservice teachers' attitudes and perceptions of IAM. Participants attributed more value to art, were more willing to apply IAM, and felt that there was less barriers for applying IAM. The study also indicated differences between art and mathematics preservice teachers' attitudes towards IAM. The differences were due more to art value than willingness or barriers. After the IAM workshop, mathematics preservice teachers put more emphasis on the importance of art to mathematics, especially with respect to making mathematics a more enjoyable subject.
Date: August 2019
Creator: Mereie, Iman Ali
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Improving Actigraphy Specificity to Better Inform Insomnia Diagnosis and Treatment Decisions

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Accurate assessment of sleep-wake patterns is important for sleep researchers and clinicians. Actigraphs are low-cost, non-intrusive, wrist-worn activity detectors used to estimate sleep-wake patterns in a natural environment for several nights. Although actigraphy shows good sensitivity (sleep detection), it has consistently demonstrated poor specificity (wakefulness detection while lying in bed relatively motionless). Because insomnia is characterized by wakefulness in bed, actigraphy may not be a valid objective measure of wakefulness for this group. It is possible that refinement of actigraphy software settings for sleep/wake algorithms might improve specificity. The current studies investigated this hypothesis by comparing wake parameters from 48 combinations of actigraphy settings to determine which sleep/wake algorithms best inform insomnia diagnosis and treatment. In the first study, none of the 48 actigraphy setting combinations consistently discriminated between adults with insomnia (n = 69) and non-insomnia (n = 80) on all three wake parameters, and no setting clearly discriminated between groups for the composite variable, total wake time. Similarly, in the second study, no setting combinations consistently discriminated between adults treated for insomnia (n = 18) and controls with untreated insomnia (n = 26) on all three wake parameters. Although two setting combinations discriminated between groups for the composite …
Date: August 2019
Creator: Francetich, Jade Marie
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Carbon Nanotubes and Molybdenum Disulfide Protected Electrodes for High Performance Lithium-Sulfur Battery Applications

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Lithium-sulfur (Li-S) batteries are faced with practical drawbacks of poor cycle life and low charge efficiency which hinder their advancements. Those drawbacks are primarily caused by the intrinsic issues of the cathodes (sulfur) and the anodes (Li metal). In attempt to resolve the issues found on the cathodes, this work discusses the method to prepare a binder-free three-dimensional carbon nanotubes-sulfur (3D CNTs-S) composite cathode by a facile and a scalable approach. Here, the 3D structure of CNTs serves as a conducting network to accommodate high loading amounts of active sulfur material. The efficient electron pathway and the short Li ions (Li+) diffusion length provided by the 3D CNTs offset the insulating properties of sulfur. As a result, high areal and specific capacities of 8.8 mAh cm−2 and 1068 mAh g−1, respectively, with the sulfur loading of 8.33 mg cm−2 are demonstrated; furthermore, the cells operated at a current density of 1.4 mA cm−2 (0.1 C) for up to 150 cycles. To address the issues existing on the anode part of Li-S batteries, this work also covers the novel approach to protect a Li metal anode with a thin layer of two-dimensional molybdenum disulfide (MoS2). With the protective layer of MoS2 …
Date: August 2019
Creator: Cha, Eunho
Object Type: Thesis or Dissertation
System: The UNT Digital Library

An Exploration of Professional Training and Professional Practice: Title IX Administrators and Meaning Making

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Federal law requires institutions to designate campus-based administrators to oversee Title IX processes and investigations, but little is known about how these have been professionally prepared for their roles. The purpose of this study was to understand the professional preparation, educational experiences, and professional training of Title IX administrators and to understand their independence in decision-making in those roles. This study utilized qualitative content analysis and a social constructionist approach to analyze data generated from interviews and document analysis. Sixteen current and former Title IX administrators (investigators, deputy coordinators, coordinators) provided their perspectives on their professional training and development. Using frameworks of work/professional socialization and professions theory, findings illustrated complex systems for knowledge acquisition, professional preparation, and professional socialization based on factors including resources, institutional context, and role prioritization. Participants' formal education, formative experiences, position-specific training, and professional organizations training all served as preparation for their roles. Discussion focused on implications for graduate programs, training and trainers, institutions and supervisors, the field of higher education, and current Title IX practitioners regarding professional preparation for these roles.
Date: December 2019
Creator: Razo, Demesia
Object Type: Thesis or Dissertation
System: The UNT Digital Library

UV Magnetic Plasmons in Cobalt Nanoparticles

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The main goals of this research were to fabricate magnetic cobalt nanoparticles and study their structural, crystal structure, optical, and magnetic properties. Cobalt nanoparticles with average particle size 8.7 nm were fabricated by the method of high temperature reduction of cobalt salt utilizing trioctylphosphine as a surfactant, oleic acid as a stabilizer, and lithium triethylborohydride as a reducing reagent. Energy-dispersive X-ray spectroscopy (EDX) analysis confirmed the formation of cobalt nanoparticles. High resolution transmission electron microscopy images show that Co NPs form both HCP and FCC crystal structure. The blocking temperature of 7.6 nm Co NPs is 189 K. Above the blocking temperature, Co NPs are single domain and hence showed superparamagnetic behavior. Below the blocking temperature, Co NPs are ferromagnetic. Cobalt nanoparticles with a single-domain crystal structure support a sharp plasmon resonance at 280 nm. Iron nanoparticles with average particle size 4.8 nm were fabricated using chemical reduction method show plasmon resonance at 266 nm. Iron nanoparticles are ferromagnetic at 6 K and superparamagnetic at 300 K.
Date: May 2019
Creator: Bhatta, Hari Lal
Object Type: Thesis or Dissertation
System: The UNT Digital Library

PAOFLOW-Aided Computational Materials Design

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Functional materials are essential to human welfare and to provide foundations for emerging industries. As an alternative route to experimental materials discovery, computational materials designs are playing an increasingly significant role in the whole discovery process. In this work, we use an in-house developed python utility: PAOFLOW, which generates finite basis Hamiltonians from the projection of first principles plane-wave pseudopotential wavefunctions on pseudo atomic orbitals(PAO) for post-process calculation on various properties such as the band structures, density of states, complex dielectric constants, diffusive and anomalous spin and charge transport coefficients. In particular, we calculated the dielectric function of Sr-, Pb-, and Bi-substituted BaSnO3 over wide concentration ranges. Together with some high-throughput experimental study, our result indicates the importance of considering the mixed-valence nature and clustering effects upon substitution of BaSnO3 with Pb and Bi. We also studied two prototype ferroelectric rashba semiconductors, GeTe and SnTe, and found the spin Hall conductivity(SHC) can be large either in ferroelectric or paraelectric structure phase. Upon doping, the polar displacements in GeTe can be sustained up to a critical hole concentration while the tiny distortions in SnTe vanish at a minimal level of doping. Moreover, we investigated the sensitivity of two dimensional group-IV monochalcogenides …
Date: December 2019
Creator: Wang, Haihang
Object Type: Thesis or Dissertation
System: The UNT Digital Library

La vía del abandono en los cuentos de Amparo Dávila

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Amparo Davila's writing style is characterized by circumventing the boundaries between the real and the fantastic and between the known and the unknown. The author creates a narrative that evokes horror in the reader by mixing the uncanny of the unknown with the reality of the world. This study proposes that the sinister in Davila's stories are created by abandonment. This abandonment is the peremptory element of Davilian narrative and can be seen and examined throughout the author's literary work. The abandonment wields a mechanism of loneliness, madness, hopelessness and chaos that eventually provokes the sinister. The element of abandonment disturbs the main character of the story and makes him fall into an abyss from which he or she cannot escape. This abandonment is not always obvious, since most of the time the abandonment is veil by a halo of gothic and fantastic elements. The present thesis has the task of breaking down the different types of abandonment that are presented throughout this narrative, its sinister function and the theoretical and historical interpretation of the various abandonments both personal and collective that Amparo Davila presents. The route of abandonment proposed in this thesis is explained in the following three stories: …
Date: December 2019
Creator: Lopez, Rodrigo
Object Type: Thesis or Dissertation
System: The UNT Digital Library

"Driving Lessons" and Other Stories

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A study through short stories of the emotional effects on close family relationships before and after a traumatic death.
Date: December 2019
Creator: Allen, Laura Spencer
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Your Blues Ain't Like Mine: Voices from the Other Side of the Color Line

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This dissertation examines intra-racial colorism in works by writers who began their careers during the Harlem Renaissance, but whose writings span almost a century. In these writings, colorism; which can be defined as a bias directed toward an individual that is based on skin tone, is portrayed an intra-racial practice that results from the internalization of racist ideals. The practice relies on a hierarchy that most often privileges those closest to the color line. However, these depictions also show that the preponderance of skin tones can sometimes determine who is targeted. For the purposes of this study it is called reverse colorism when the bias is directed by individuals darker in skin tone toward those who are lighter. Consequently, the careful descriptions of the shades and hues of black characters becomes more than aesthetics and can be seen as a coded reference to experiential differences. While Alain Locke hailed the start of the Harlem Renaissance to signal the rise of The New Negro, the writings featured by female writers in this dissertation advance a less optimistic reality for women, who had to contend with both inter- and intra-racial bias because of their skin tone. Colorism is identified as a particularly …
Date: December 2019
Creator: Edwards, Cheri Paris
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Tchaikovsky's Piano Concerto No. 1 In B-Flat Minor, Op. 23: A Newly Arranged Edition of the Orchestral Reduction

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As it stands, only one arrangement of Tchaikovsky's Piano Concerto No. 1, Op. 23 orchestral reduction exists, which is by Tchaikovsky himself. A number of critical editions of the piece exist, but none of them cover the subject of the material within the orchestral reduction. Tchaikovsky wrote the reduction from a compositional rather than a pianistic perspective, thus some passages present awkward technical challenges. The purpose of this dissertation is ultimately to contribute to the repertoire of accompanists by producing a new edition of Tchaikovsky's Piano Concerto No. 1. I created my arrangement through a process of practical trial and error as well as observing the strategies used by other arrangers of orchestral reductions. Through a series of carefully selected omissions, note rearrangements, visual adjustments, and editorial changes, I simplified the reduction as a whole. I sought to improve the readability of the music by reducing accidentals as much as possible and also incorporating small-print cues into the main staves. Each minor adjustment or major revision contributes cumulatively to the ease of execution of the accompanimental part as a whole. Although Tchaikovsky's reduction is authentic and authoritative, a newly revised and simplified version would be useful for collaborative pianists. Thus, …
Date: December 2019
Creator: Parys, Marcin
Object Type: Thesis or Dissertation
System: The UNT Digital Library