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Design Of Metal Oxides/Metal Sulfides For The Improvement Of Sodium Ion Batteries, David E. Flores

Theses and Dissertations

Herein, the improvement in performance for sodium ion batteries (NIBs) is discussed from available literature and work conducted in the laboratory setting to demonstrate the ability of sodium to perform in the world of energy storage. The reason that sodium is being explored as an alternative to Lithium in energy storage devices is because of the potential depletion of the lithium in the world causing lithium prices to surge. Researchers show that many Sn, Sb, Ge, and other composites perform well as anode materials within NIBs. The research conducted in the dissertation applies the Forcespinning method to produce fibers for …

Study Of Latent Heat Thermal Energy Storage Systems For Concentrated Solar Power Plants, Hermes Chirino

Theses and Dissertations

Concentrated Solar Power (CSP) using phase change material (PCM) as the storage medium in the Thermal Energy Storage (TES) system is a promising technology for large scale utilization of solar thermal energy because heat latent heat thermal energy storage (LHTES) systems can store more energy as the latent heat during the melting process.

This study analyzes the different dimensionless parameters from the 1-D transient enthalpy-based mathematical model used to simulate the heat transfer and flow within the LHTES system. These dimensionless parameters are varied and analyzed with the main objective of increasing thermal energy storage efficiency and exergy efficiency of …

Hablando De Negocios: Three Rio Grande Valley Businesses During The Great Depression, 1929-1939, Karla A. Lira

Theses and Dissertations

The Rio Grande Valley is in the South most tip of Texas and borders Northern Mexico, it includes Willacy, Cameron, Hidalgo, and Starr Counties. Scholars have focused on gender, agriculture, and labor of the area. However, historians have failed to research the region through a business perspective during the Great Depression. This thesis then seeks to analyze ways in which the Great Depression affected the Rio Grande Valley through the research of two stores and one business in the area: The Manuel Guerra Store, Edelstein’s furniture store, and John Shary’s land selling business. Its objective will fill an existing gap …

Growth And Characterization Of Gallium Oxide Thin Films And Devices, Jorge Castillo

Theses and Dissertations

Gallium oxide has promising physical and electrical properties for power applications and optoelectronics. thermally grown oxide developed from sputtered GaN layers and gallium oxide substrates will be characterized. The study will evaluate a variety of temperatures in order to investigate the advantages and disadvantages on each of the synthetization techniques.

College Readiness Indicators Of First-Generation Hispanic High School Students In South Texas, William Morley

Theses and Dissertations

The purpose of this study was to determine if a relationship exists between first generation Hispanic student participation in an AVID program and college readiness. The dependent variable, college readiness, was measured by passing the Texas Success Initiative (TSI) Reading, Writing, and Math assessment. Predictor variables included Advancement Via Individual Determination (AVID) elective course participation, Advanced Placement courses taken, Advanced Placement Exams taken, Advanced Placement Exams passed, Dual Enrollment Courses Passed, and ACT Composite score. A factor analysis was performed on the predictor variables, resulting in three independent variables for the study: AVID elective course participation, Average of T-scores for …

Hormonal Influence On Female Consumption Of Revealing And Sexy Fashion Products, Ngoc B. Pham

Theses and Dissertations

This doctoral dissertation addresses the biological and psychological components of consumers’ decision-making processes. Particularly, it investigates the impact of female sex hormones on women’s consumption behaviors regarding fashion products. These hormones reach peak level when women are near ovulation, and this research examines how these hormones, when at peak level, influence women’s attitudes and purchase intention towards sexy and revealing fashion products.

The research is based on two theoretical frameworks: ovulatory shift hypothesis (OSH) and theory of reasoned action (TRA). Specifically, the OSH, based on the female ovulatory cycle postulates that women change their sexual preferences for men with perceived …

Numerical Cognition In Action: Hand Trajectories Reveal Effects Of Early Musical Training On Numerical Processing In Spanish-English Bilingual Musicians, Daniel Arturo Pizaña

Theses and Dissertations

The mouse-tracking study examined whether early musical experience leads to changes of inhibitory control in numerical processing for bilingual speakers, as has not investigated in previous studies. Twenty-eight Spanish-English bilingual students completed two Stroop-like numerical and physical size judgment tasks via a mouse-tracking paradigm. Results showed that response times were slower during both incongruent and neutral trials for bilinguals who had received early musical training (before age 13) when compared to bilinguals who had received late musical training (after age 13) across tasks. Furthermore, hand trajectories revealed that a spatial attraction toward the incorrect response was more pronounced in bilinguals …

The Origins And Development Of John F. Kennedy And Lyndon B. Johnson's Perceptions Of American Foreign Policy Toward East Asia, Juan C. Razo Jr.

Theses and Dissertations

The administrations of John F. Kennedy and Lyndon B. Johnson focused extensively on foreign affairs in East Asia related to China, Laos, and Vietnam. Examining the development of their respective perceptions proved instrumental in comprehending their approaches to the geopolitics of the region. The overall structure of this thesis includes an analysis of their tenure in Congress, a breakdown of the first-half of Kennedy’s presidency, an emphasis on the transition period between Kennedy and Johnson, an examination of Johnson’s presidency, and concluding with a detailed comparison of their foreign policy toward East Asia. Their differing perceptions to the regional geopolitics …

Essays On Financial Decision Making, Corey A. Shank

Theses and Dissertations

Individuals make financial decisions daily, yet the literature on the mechanisms that drive financial decisions is limited. This dissertation looks to examine how physical characteristics, and personality subconsciously influence financial decision making by conducting an experiment. Furthermore, this dissertation examines biased decision making in the betting market by using data from covers.com. First, this dissertation finds that the cognitive impairments associated with having a higher body mass index is positively related to poor financial decision making and being more likely to commit the present bias, and distorting probabilities. Second, this dissertation finds that business students are more apt to fit …

Association Between Hispanic Parents' Attitudes And Knowledge Regarding Obesity And Their Children's Body Mass Index: Implications For The Development Of Obesity, Renee Starr

Theses and Dissertations

According to the World Health Organization (WHO, 2017), more than 1.9 billion adults age 18 and older are overweight and over 650 million are obese. Data collected through the Centers for Disease Control indicates the prevalence of U.S. adults who are overweight and obese is estimated at 36.5% and the national childhood obesity rate is more than 12.7 million (17%), with approximately one in six school-aged children reaching the obesity level (Ogden, Carroll, Fryar, & Flegal, 2015). Hispanic children have the highest levels of obesity among all racial/ethnic groups (21.9%) and obesity rates are especially prevalent among impoverished Hispanics residing …

Synthesis Of Tetraethyl ((2-Amino-1,4-Phenylene)Bis(Methylene)) Bis(Phosphonate): An Intermediate In The Synthesis Of Amino-Substituted Conjugated Materials, Ariel Ivan Torres Burgueno

Theses and Dissertations

Discussed here are the syntheses of the phosphonate precursors for the Wittig-Horner synthesis of poly-phenylene vinylene (PPV) and distyrylbenzene (DSB) derivatives and their respective distyrylbenzene analogs containing amino moieties. The synthesis of the different compounds was achieved through bromination, Michaelis-Arbuzov reaction, reduction of the nitro group with a commercial cobalt sulfide catalyst and sodium borohydride. Preliminary evidence for the synthesis of amino substituted distyrylbenzene and of nitro/alkoxy substituted poly(p-phenylene vinylene) was obtained. Characterization of the products was performed by 1H-NMR. Preliminary results of the synthesis of a novel amino-substituted distyrylbenzene (DSB) are presented. The luminescence of the new DSB was …

Hydrodesulfurization Of Dibenzothiophene Using Lanthanum Doped Comos2, Carolina Valdes Bracamontes

Theses and Dissertations

Hydrodesulfurization (HDS) is a technique used in petrochemical industry for the removal of sulfur from crude oil. Using dibenzothiophene (DBT) as a target molecule and CoMoS2 catalysts doped with various concentrations of lanthanum were studied for catalytic activity in the removal of DBT from solution. Catalysts were synthesized using ammonium tetrathiomolydate, cobalt chloride and lanthanum nitrate under a solvothermal decomposition in decalin at 350 °C with H2 gas at 160 psi. To evaluate decomposition effects, a second set of catalyst precursors were decomposed in a tube furnace at 450 °C under a constant flow of 10%/90% H2/Ar. Characterizations of the …

Faculty Perceptions Of Effectiveness And Impact Of Professional Development For Teaching, Research, And Service, Claudia Vela

Theses and Dissertations

The purpose of this explanatory mixed methods study was to examine faculty perceptions of effectiveness and impact of professional development for teaching, research, and service in a higher education institution in South Texas. This study provided quantitative and qualitative data from 165 faculty members from a Hispanic Serving Institution in South Texas. Participants in this research consisted of tenured 56.9% (n = 95) and tenure-track 41.1% (n = 69) faculty members who taught in different departments in the colleges of Health Affairs, Sciences, Liberal Arts, Engineering and Computer Sciences, Business and Entrepreneurship, and Education and P-16 Integration. The …

Nanoenergetic Gas Generators Based On Metal Hydroxides, Srbuhi Yolchinyan

Theses and Dissertations

The metal oxide based nano thermites have been studied extensively, yet another closely related systems based on metal hydroxides were surprisingly overlooked. For the first time, the thermodynamic calculations using HSC Chemistry-7 and Thermo software, were performed for a collection of 22 novel nano-thermite systems based on aluminum and metal hydroxides, and four representative systems based on bismuth, copper, cerium and nickel hydroxides were characterized using differential scanning calorimeter, scanning electron microscope, and pressure discharge dynamic evaluation. The strongest performance was recorded in Al-Bi(OH)3 system with about 4.9 MPa peak pressure for 0.2 g charge mass. Bismuth oxide and hydroxide …

The Acute Effects Of Resistance Exercise With Blood Flow Restriction Versus Traditional Resistance Exercise On Arterial Compliance And Energy Expenditure In Recreationally Active Males And Females, Danny D. Dominguez

Theses and Dissertations

PURPOSE: The aim of this study was to investigate the acute effects of various intensities of volume matched resistance exercise with blood flow restriction (BFR) and traditional resistance exercise on hemodynamic variables, arterial compliance, oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (RER), and energy expenditure (EE) during exercise and after exercise.

RESULTS: Significant condition main effects (p < 0.05) were found for RPE, HR, crPWV, fdPWV, LAE, SAE, TVI, RER during and postexercise. BFR25 cause greater increases in RPE and HR. BFR50 caused marked increases in SAE, crPWV, and fdPWV.

CONCLUSION: All BFR and traditional exercise conditions found no significant differences in EE, VCO2, and VO2. The lack of differences is likely due to time of protocol. Further protocols should implement greater time of exercise, as BFR had increased hemodynamic …

Security Evaluation Of Virtualized Computing Platforms, Ganesh Reddy Gunnam

Theses and Dissertations

In this thesis, security experiments were conducted to evaluate embedded security protocol performance of two leading server operating systems, Apple’s MAC OS server LION Vs. Microsoft’s Windows server 2012 R2 OS under different types of security attack. Furthermore, experiments were conducted to understand and evaluate the effect of virtualization using Hyper-V with Windows 2012 R2 OS on MAC hardware platform. For these experiments, connection rate, connection latency, non-paged pool allocations and processor core utilization for different OS, virtual machines, and under different traffic types were measured.

Brava & Gloria: A Mexican Counterstory Screenplay, Jose David Garcia Gilling

Theses and Dissertations

“Brava & Gloria: A Counterstory Screenplay” is a thesis work which combines the theoretical aspects of Latinx representation in films with a full-length, feature film screenplay. In this work I use speculative fiction aesthetics to address the matter of representation and I create a version of how I would like to see Latinxs represented on screen. The story of “Gloria and Brava” is a medium to achieve this. Even though it does not mimic my personal experience as an immigrant, the core of the story is my family’s and my own experience as a Latino in the United States. Consequently, …

Single Tower Crane Allocation Models Using Ant Colony Optimization, Carlos Abelardo Trevino

Theses and Dissertations

The construction industry greatly benefits from the utilization of heavy machines and equipment to accomplish successful projects. Tower cranes, in specific, have a crucial role in the transportation of material loads across the site. Because these machines are fixed to the ground, it is essential for planners and managers to position them in a location that provides the most efficient transfer of materials possible. This is commonly known as the tower crane allocation problem, and many researchers have attempted to optimize the tower crane location using mathematical, artificial intelligence, and simulation approaches. However, many works from the literature contain critical …

Two Essays On International Capital Flows And Cross-Listings, Lu Sui

Theses and Dissertations

This dissertation explores two interesting issues: international capital flows and cross-listings. With high volatility of capital flows and imbalance of capital flows between emerging and advanced economies, the topic of capital flow management is always attractive to researchers and policy makers. The first essay explore how capital flows in G20 countries are significantly impacted by pull and push factors. The results show that international capital flows are significantly associated with domestic financial development, which is measured by stock market liquidity and domestic credit. Moreover, international capital flows are affected by some push factors such as, the growth of world economy …

Regression-Discontinuity Analysis Of The Effects Of Government Housing Policies, Alejandro Rojas

Theses and Dissertations

An influential literature has applied regression-discontinuity (RD) analysis to investigate the effects of government housing policies. This literature has failed to identify substantial effects of these policies, but may also suffer from various biases and limitations. This dissertation carefully examines what, if any, issues face RD analysis in this context. Chapter II considers the Affordable Housing Goals (AHGs) and Community Reinvestment Act (CRA), affordable housing policies that compel Fannie Mae and Freddie Mac (F&F) and depository institutions, respectively, to increase access to mortgage credit for borrowers perceived by some as “underserved” by the mortgage market. Chapter III considers the overall …

Utilizing Accelerometer Telemetry Tags To Compare Red Snapper (Lutjanus Campechanus) Behavior On Artificial And Natural Reefs, Ethan T. Getz

Theses and Dissertations

The Texas Parks and Wildlife Department Artificial Reef Program has deployed over 2,800 hectares of reefing area composed of petroleum platforms, steel vessels, and concrete. Artificial reefs have been shown to support many important reef fishes such as red snapper (Lutjanus campechanus), however, few studies have compared fish behavior on artificial reefs and natural habitats. We examined activity levels, behavioral patterns and habitat preferences of red snapper over natural reefs, oil platforms and submerged ships. Telemetry tags (Sonotronics model MTT) with tri-axial acceleration range, average depth, and average temperature were programmed to optimize data collection and tag life. …

Genetic Diversity Of Kemp's Ridley (Lepidochelys Kempii) Sea Turtles On South Padre Island, Texas, Hilary R. Frandsen

Theses and Dissertations

In 2010, researchers observed an abrupt decline in nesting numbers of the Kemp’s ridley following 35 years of positive growth. In wake of this halt, and subsequent lowered nesting averages, evaluation of the genetic diversity of remaining individuals is relevant to investigate the plausibility of a genetic bottleneck, and determine the reproductive stability of the Kemp’s ridley.

Here, I evaluate the genetic diversity within a sampling of the Kemp’s ridleys on South Padre Island using two methods: targeting the mitochondrial control region and targeting the complete mitochondrial genome. Opportunistic samples were donated from juvenile ridleys on the East coast, and …

Des And Tdes Performance Evaluation For Non-Pipelined And Pipelined Implementations In Vhdl Using The Cyclone Ii Fpga Technology, Edni Del Rosal

Theses and Dissertations

Two ongoing issues that engineers must face in the new era of data analytics are performance and security. Field Programmable Gate Arrays (FPGAs) offer a new solution for optimizing the performance of applications while the Data Encryption Standard (DES) and the Triple Data Encryption Standard (TDES) offer a mean to secure information. In this thesis we present a Non-Pipelined and Pipelined, in Electronic Code Book (EBC) mode, implementations in VHDL of these two commonly utilized cryptography schemes. Using Altera Cyclone II FPGA as our platform, we design and verify the implementations with the EDA tools provided by Altera. We gather …

Oxidation Of Dibenzothiophene To Dibenzothiophene-Sufone Using A Molybdenum (Vi) Oxide Catalyst: A Kinetic Study Testing Solvent Dependency And Mole Ratio Efficiency, Tomas Trevino Jr.

Theses and Dissertations

Oxidative desulfurization (ODS) is currently a solution to hydrodesulphurization. Currently, industrial usage of hydrodesulphurization (HDS) is the common source for petroleum purification. Unfortunately, HDS comes with environmental and economical ramifications. Due to the problems and potential hazards being presented with HDS, ODS has become a topic of interest in research development. A kinetic study using molybdenum (VI) oxide as a catalyst was used in oxidative desulfurization. Factors such as mole ratio and solvent dependency were tested for efficiency. As activation energy was calculated to show maximum efficiency with respect to temperature and concentration. Gas Chromatography, FT-IR, and Mass Spectroscopy were …

A Study Of Perceived Leadership Styles As It Affects The Decision-Making Process Employed By Eleven Catholic School Principals In South Texas, Mary Olivia Agbakoba

Theses and Dissertations

Catholic School principals play an important role in the development of students' spiritual, social, and academic wellbeing. Consequently, in order to improve students' spiritual, social, and academic skill, it is vital to study the perceived leadership styles and decision-making of Catholic School Principals. Research questions include: "Is there a relationship between Catholic School Principals and teachers' perceptions on principals' leadership styles?", and "Is there an association between decision type and decision-making style used?" 11 Catholic School Principals and 179 Catholic School Teachers completed a paper and pencil survey that assessed the perceived leadership styles of principals. Data was analyzed using …

Coding The Discourse And Translingual Strategies Of Collaborative Writing Of Secondary Education Students, Zane Lee Arredondo

Theses and Dissertations

Kenneth Bruffee used collaborative writing pedagogy to help reacculturate students’ discoursal identities to help them adhere to the expectations of the academic community. Although studies have shown that reacculturation may not exactly happen, Collaborative writing pedagogy still has maintained its presence within Composition studies since then and has been adapted into being implemented into digitally shared spaces. However, one aspect has been overlooked about physical shared spaces, the conversations themselves being studied. This study explores Kenneth Bruffee’s constructive conversations among secondary students within collaborative writing pedagogy. The collaborative sessions are recorded and viewed with a translingual lens applying Johnny Saldana’s …

In His Wake: Applying Life's Truths In Fiction, Joseph M. Balderas

Theses and Dissertations

The culmination of the creative work and its introduction attempt to delve into the psyche of what it means to lose someone you love. The screenplay explores the grieving process and the coping mechanisms that accompanies it, with an examination on how far some people are willing to go for closure.

To reach my conclusions, I draw from my own life experience, the experiences of others, and a fine amount of research. It also means to shed light on the impermanent mental strain that chaperon’s grief.

Variables Relevant To Self-Efficacy: Mexican-American High School Students With Specific Learning Disabilities, Matilde Barrera Alaniz

Theses and Dissertations

The purpose of this study is to ascertain if a relationship exists between self-efficacy and grade point average (GPA), age, gender, language proficiency, socioeconomic status, and failed grade levels during school career among Mexican-American high school students with specific learning disabilities (SLD) residing along the southwestern state of the Mexican border. Moreover, to learn if a relationship exists between motivation and the above variables. This study also observed if a relationship between motivation as measured by the Academic Self-Regulation Questionnaire (SRQ-A) (i.e., external regulation, introjected regulation, identified regulation, and intrinsic motivation) and GPA existed; it also observed the correlation between …

Effect Of Processing Parameters On The Electrochemical Performance Of Forcespun Metal Oxide/Carbon Composite Fibers For Li-Ion Batteries, Howard A. Campos

Theses and Dissertations

Metal oxides have been gaining interest as electrode materials for rechargeable Li-ion batteries due to various properties including low cost, low toxicity, and high theoretical capacity. In this research work the effect of two different metal oxide/carbon fiber composites, Fe3O4/C and ZnO/C, on the electrochemical performance for Li-ion batteries will be explored. This is also the first time that results are reported, to the best of our knowledge, of these fiber composites through the Forcespinning ® method. Scanning electron microscopy (SEM), Energy-Dispersive X-ray Analysis (EDS), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), and electrochemical analysis were used to investigate …

Aristotle, Redemption, And The Conquest Of The Americas, Luis Angel Buentello

Theses and Dissertations

The central question addressed in my thesis is the claim that the even though the conquest of the Americas by the Spaniards was a brutal and murderous process, the Spanish imperial project in the Americas, based on Aristotelian ideology, resulted in the most beneficial and least harmful form of conquest conceivable in comparison to the next great empire of the age, the British Empire.

The founding pillars of Spain’s overseas empire in the Americas, based on an Aristotelian framework, produced a synthesis of political thinking that brought about greater benefits to the native populations, and slave populations, subsumed under the …