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

Description: 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 structu… more
Date: August 2019
Creator: Cha, Eunho
Partner: UNT Libraries

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

Description: 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 reve… more
Date: August 2019
Creator: King, Skylar Dawn
Partner: UNT Libraries

Cesarean Section Delivery and Exclusive Breastfeeding in Pakistan: Emerging Challenges

Description: This research examined two interrelated issues relevant to maternal and neonatal health in Pakistan, namely, the rising rates of C-section delivery and low rates of exclusive breastfeeding. By using the Andersen's health behavioral model to frame two empirical studies, the data from the Pakistan Demographic and Health Survey (PDHS) 2012-13 was used. The first empirical study examined the correlation between place of delivery and the odds of cesarean section in Pakistan. Not all Pakistani women … more
Date: August 2019
Creator: Nazir, Saman
Partner: UNT Libraries

Characterization, Analysis, and Optimization of Rotary Displacer Stirling Engines

Description: This work focuses on an innovative Rotary Displacer SE (RDSE) configuration for Stirling engines (SEs). RDSE features rotary displacers instead of reciprocating displacers (found in conventional SE configurations), as well as combined compression and expansion spaces. Guided by the research question "can RDSE as a novel configuration achieve a higher efficiency compared to conventional SE configurations at comparable operating conditions?", the goal of this study is to characterize, analyze, an… more
Date: December 2019
Creator: Bagheri, Amirhossein
Partner: UNT Libraries

Charpy Impact Testing of Twinning Induced Plasticity and Transformation Induced Plasticity High Entropy Alloys

Description: High entropy alloys (HEAs) are a new class of solid solution alloys that contain multiple principal elements and possess excellent mechanical properties, from corrosion resistance to fatigue and wear resistance. Even more recently, twinning induced plasticity (TWIP) and transformation induced plasticity (TRIP) non-equiatomic high entropy alloys have been engineered, promising increased strength and ductility as compared to their equiatomic counterparts. However, impact and fracture resistance o… more
Date: August 2019
Creator: Zellner, Samantha R
Partner: UNT Libraries

Choice Androgyny

Description: This work provides an alternative theory of gendered consumption that explains chronic and situational shifts in consumers' preferences for masculine, feminine, and androgynous choices, beyond the effects of gender identities.
Date: August 2019
Creator: Jones, Niusha
Partner: UNT Libraries

Cold-Formed Steel Member Connections Using BAC Screw Fasteners

Description: In this project, the main research objective is intend to seek criteria for evaluating the capacity of BAC screw fasteners with mixed configuration of waterproof seal washer, sealer tape and different pre-drill holes to determine shear and tension strength values for the screws used in cold-formed steel connections. The thesis presents the design methods and test program conducted to investigate the behavior and strength of the screw connections in shear and tension test. Test results were comp… more
Date: May 2019
Creator: Li, Xun
Partner: UNT Libraries

Comparing Cognitive Functioning in White Mexican/Mexican Americans and non-Hispanic White Americans with and without Type 2 Diabetes

Description: To better understand the impact of type 2 diabetes, the relationship between ethnicity, specifically Mexican/Mexican American ethnicity, and the disease must be further investigated. This study specifically examined the cognitive impact of type 2 diabetes. Data from the 2014 Health and Retirement Study was used to compare the cognitive functioning of non-Hispanic White (n = 10,658) and White Mexican/Mexican American (n = 847) individuals, age 50+ years, with and without type 2 diabetes. Serial … more
Date: August 2019
Creator: Saldana, Samantha Lee
Partner: UNT Libraries

Complex-Restricted Repetitive Patterns of Vocal Behavior of Individuals with High Functioning Autism: An Innovative Intervention

Description: Repetitive verbal patterns of speech are a trait associated with high-functioning autism (HFA). For some, this higher-order restricted, repetitive behavior impedes learning, social opportunities, and access to work environments. Despite emerging motivation for establishing social relationships, some individuals with HFA lack the behavioral prerequisites to establish meaningful relationships. The purpose of this study is to demonstrate the effectiveness of teaching interaction to decrease hig… more
Date: May 2019
Creator: Flatt, Kimberlee Kay
Partner: UNT Libraries

Computational Development of Trimetallic Cyclotrimers for Gas-Filtration Applications through Non-Covalent Interactions

Description: Photophysical properties of an array of various polyaromatic hydrocarbons were benchmarked with B3LYP, M06 and B97D methods coupled with Pople and CEP-31G(d) basis sets. Results from the benchmark show the importance of diffuse basis sets when modeling the electronic properties of highly conjugated systems and provide qualitative reliable accuracy with certain levels of theory. B97D and M06 are applied to modeling pyrene adducts governed by non-covalent interactions in both gaseous and condense… more
Date: December 2019
Creator: Williams, Christopher M.
Partner: UNT Libraries

Computational Studies of C-H Bond Activation and Ethylene Polymerization Using Transition Metal Complexes

Description: This work discusses the C-H bond activation by transition metal complexes using various computational methods. First, we performed a DFT study of oxidative addition of methane to Ta(OC2H4)3A (where A may act as an ancillary ligand) to understand how A may affect the propensity of the complex to undergo oxidative addition. Among the A groups studied, they can be a Lewis acid (B or Al), a saturated, electron-precise moiety (CH or SiH), a σ-donor (N), or a σ-donor/π-acid (P). By varying A, we seek… more
Date: May 2019
Creator: Parveen, Riffat
Partner: UNT Libraries

Computational Studies of Catalysis Mediated by Transition Metal Complexes

Description: Computational methods were employed to investigate catalytic processes. First, DFT calculations predicted the important geometry metrics of a copper–nitrene complex. MCSCF calculations supported the open-shell singlet state as the ground state of a monomeric copper nitrene, which was consistent with the diamagnetic character deduced from experimental observations. The calculations predicted an elusive terminal copper nitrene intermediate. Second, DFT methods were carried out to investigate the … more
Date: May 2019
Creator: Jiang, Quan
Partner: UNT Libraries

Construction Management Methods and Techniques in Army Tactical Shelter

Description: This thesis presents a research effort aimed at developing using construction methods and techniques in army tactical shelter. The beginning step focuses on developing and identifying different activities and work breakdown structure applicable in shelter prototype. The next step focuses on identifying resource allocation. This include allocate resources based on the delivered project as per alternative one and for the second alternative as optimization, resource allocation modified and tried t… more
Date: December 2019
Creator: Yeganehtalab, Babak
Partner: UNT Libraries

Decision Making in Alternative Modes of Transportation: Two Essays on Ridesharing and Self-Driving Vehicles

Description: This manuscript includes an investigation of decision making in alternative modes of transportation in order to understand consumers' decision in different contexts. In essay 1 of this study, the motives for participation in situated ridesharing is investigated. The study proposes a theoretical model that includes economic benefits, time benefits, transportation anxiety, trust, and reciprocity either as direct antecedents of ridesharing participation intention, or mediated through attitude towa… more
Date: May 2019
Creator: Amirkiaee, Seyede Yasaman
Partner: UNT Libraries

Deep Learning Approach for Sensing Cognitive Radio Channel Status

Description: Cognitive Radio (CR) technology creates the opportunity for unlicensed users to make use of the spectral band provided it does not interfere with any licensed user. It is a prominent tool with spectrum sensing functionality to identify idle channels and let the unlicensed users avail them. Thus, the CR technology provides the consumers access to a very large spectrum, quality spectral utilization, and energy efficiency due to spectral load balancing. However, the full potential of the CR techno… more
Date: December 2019
Creator: Gottapu, Srinivasa Kiran
Partner: UNT Libraries

Defining Components Linked to Bacterial Nutritional Utilization of Cyanide as a Sole Nitrogen Source

Description: One of the challenges in biology is placing a function on the myriad of gene sequences having become available from rapid advances in genome sequencing. One such example is a gene cluster (Nit1C) found in bacteria that is tied to the unusual ability of certain bacteria to grow when supplied cyanide as the sole nitrogen source. The term cyanotrophs has been applied to such bacteria, for which a genetic linkage between cyanotrophy and Nit1C was demonstrated for 10 separate bacteria. In additio… more
Date: May 2019
Creator: Jones, Lauren Brittany
Partner: UNT Libraries

Depression, Religious Behaviors and Social Support as Predictors of Health-Related Quality of Life among HIV Positive Individuals

Description: The goal of the current study was to evaluate the ways in which religious behaviors and perceived social support are associated with the relationship between depressive symptoms and health-related quality of life for this group. We hypothesized (1) that religious behaviors moderate the relationship between depressive symptoms and health-related quality of life, (2) perceived social support mediates the relationship between depressive symptoms and health-related quality of life and (3) that reli… more
Date: December 2019
Creator: Davis, Cameron W
Partner: UNT Libraries

Design Method of Cold-Formed Steel Framed Shear Wall Sheathed by Structural Concrete Panel

Description: The objective of this research is developing a new method of design for cold-formed steel framed shear wall sheathed by ¾" thick USG structural panel concrete subfloor using a predictive analytical model and comparing the results obtained from the model with those achieved from real testing to verify the analytical model and predicted lateral load-carrying capacity resulted from that. Moreover, investigating the impact of various screw spacings on shear wall design parameter such as ultimate st… more
Date: December 2019
Creator: Ashkanalam, Aida
Partner: UNT Libraries

Design, Synthesis and Characterization of Polymer and Protein Coated Hybrid Nanomaterials: Investigation of Prototypes for Antimicrobial and Anticancer Applications

Description: This work involves synthesis and characterization of isotropic and anisotropic noble metal nanoparticles for applications ranging from antimicrobial uses to anticancer applications. These nanomaterials are stabilized in genuinely benign biomaterials ranging from polymers to cross linked proteins for targeted cancer treatments. The nanoparticles are found to have tunable optical properties.
Date: May 2019
Creator: Korir, Daniel Kiplangat
Partner: UNT Libraries

Development and Testing of Gold(I) and Europium(III) Based Sensors for Environmental Applications

Description: This dissertation focuses on the development, characterization, and analysis of luminescent materials and coatings for sensing applications, including CO2, heavy metals, and silver. Chapter 2 involves the use of a gold(I) pyrazolate trimer that is able to detect silver ions with an AgNP medium. Detection of silver is vital, because there is an influx of silver into our environment caused by the increased use of AgNP. Therefore, having a sensor that is able to differentiate between and detect on… more
Date: May 2019
Creator: Benton, Erin Nicole
Partner: UNT Libraries

Disasters, Smart Growth and Economic Resilience: An Empirical Analysis of Florida Cities

Description: This dissertation examines the relationship between economic resilience, disaster experience, and smart growth policies at the local government level. The study is based upon three research questions that examine spatial distribution of economic resilience in Florida cities, and examines the impact of disaster experience, and smart growth policies adopted by local governments on economic resilience. Based upon the bounce-forward approach (Cowell, 2013; Klein et al. 2003), economic resilience is… more
Date: August 2019
Creator: Chatterjee, Vaswati
Partner: UNT Libraries

Diverse Learners in the Classroom: Students with Special Needs Enrolled in Science, Technology, Engineering, and Mathematics (STEM) Texas Public Classrooms

Description: The purpose of this study was to determine if students with special needs participating in an inclusive classroom can learn the skills related to a STEM career as compared to the general student population. The study involved seventh grade students from two rural middle schools in north central Texas and was framed through a constructivist lens using a quasi-experimental design with a convenience sample. The Solenoid Invention Kit Assessment and the STEM Semantics Survey used in this study were… more
Date: August 2019
Creator: Briones, San Juanita G
Partner: UNT Libraries

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

Description: 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 pr… more
Date: August 2019
Creator: Macdonald, Neil
Partner: UNT Libraries
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