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Acenaphthene and 1,10-Phenanthroline-Fused Βeta-Functionalized Porphyrins
A series of acene-fused porphyrins and 1,10-phenanthroline-fused porphyrins were synthesized and characterized via NMR spectroscopy and mass spectrometry. The acene-fused porphyrins exhibit unique optoelectronic properties, most notably they exhibit highly red-shifted absorption bands. The 1,10-phenanthroline-fused porphyrins are of interest for their ability to bond to as variety of metals to form chelation complexes.
Date:
December 2023
Creator:
Arvidson, Jacob Randall
System:
The UNT Digital Library
Acute and Sublethal Impacts of Crude Oil Photo-Induced Toxicity in an Early Life Stage Marine Fish (Sciaenops ocellatus) and Invertebrate (Americamysis bahia)
We investigated the modifying effects of ultraviolet (UV) light and chemical dispersant (Corexit 9500A) on crude oil toxicity in juvenile mysids (≤ 24 h) (Americamysis bahia) and larval red drum (24-72 hpf) (Sciaenops ocellatus). These results demonstrate that crude oil toxicity significantly increases with co-exposure to environmentally relevant UV levels in both species, indicating photo-induced toxicity. This toxicity was further exacerbated by the application of chemical dispersants which increased the dissolution and concentration of oil-derived polycyclic aromatic hydrocarbons (PAHs) in test solutions. To better understand the mechanisms and initiating events of this observed photo-induced toxicity, the incidence of apoptotic cell death and global transcriptomic changes were assessed in larval red drum (24-72 hpf) following co-exposure to crude oil and UV. These results showed that co-exposure to UV and low concentrations of crude oil (<1 µg/L ∑PAH50) induced apoptotic cell death in skin and eye tissue and altered transcriptomic pathways related to visual processing and dermatological disease. To link these cellular and molecular impacts of photo-induced toxicity to apical endpoints of ecological performance, sublethal impacts to growth, metabolic rate, and visually mediated behaviors were explored in larval red drum at 2 developmental stages. These results suggested that earlier life stages may …
Date:
December 2023
Creator:
Leads, Rachel Renee
System:
The UNT Digital Library
Additive Friction Stir Deposition of Al-Ce Alloys for Improved Strength and Ductility
Additive friction stir deposition (AFSD) is a solid-state additive manufacturing (AM) technique that breaks down large constituent particles into more refined and uniformly disturbed microstructure. AFSD was used to print Al-Ce alloys. Current commercial Al-alloys upon elevated temperatures go through dissolution and coarsening of strengthening precipitates causing mechanical degradation of these alloys. Al-Ce alloys do not have this issue as cerium's low solubility restricts dissolution into the aluminum matrix at elevated temperatures, thus giving great thermal stability to the microstructure. Al-Ce alloys lack solid solubility that affects the solid solution strengthening and precipitation strengthening. Al-Ce alloys have limitation at room temperature as they can only reach a maximum of ~65 MPa yield strength. Elements like magnesium have been added to alloy to enable solid solution strengthening, and scandium to enable precipitation strengthening to improve strength before going through the AFSD process. By adding new elements to the Al-Ce alloys, an increase in the yield strength from ~60 MPa to ~200 MPa was achieved before AFSD. The casted alloys form coarse particles that reach 300 µm in size; resulting in stress concentration that causes material fracture before necking, giving >10% ductility. AFSD breaks down these coarse particles to increase strength and …
Date:
December 2023
Creator:
Davis, Devin Fredric
System:
The UNT Digital Library
An Analysis of Litigation against North Carolina Educators and School Districts under the North Carolina Tort Claims Act
This dissertation discussed the impact of the North Carolina Tort Claims Act and the history of governmental immunity that has protected school districts and school employees in North Carolina. The research question addressed was: how have North Carolina state courts interpreted the North Carolina Tort Claims Act in litigation against North Carolina school districts and their employees? The North Carolina Tort Claims Act provided citizens with a vehicle to sue local governmental agencies and their employees, such as school employees. The act also provided immunity for schools, especially for excessive damages in the case of negligence by an employee. The study examined how state courts have responded to different plaintiffs since the passage of the North Carolina Tort Claims Act in 1951. The decisions in the cases analyzed have been mostly favorable to schools, which has strengthened immunity for school employees. There were four legal aspects addressed by the courts after the passage of the North Carolina Tort Claims Act either most frequently or were unique to the case law of North Carolina. Those legal aspects were tests of school districts' governmental immunity; contributory negligence on the part of the plaintiff; the official capacity of school employees in lawsuits; and …
Date:
December 2023
Creator:
Harned, Jason Douglas
System:
The UNT Digital Library
Analysis of Sensory Integration Techniques on Automatically Maintained Problem Behavior
Sensory integration techniques are a common treatment procedure among occupational therapists. The goal is to "apply" input that competes with input from problem behavior. Although this is a commonly recommended intervention, there is limited empirical evaluation with adults with intellectual disabilities. Therefore, we evaluated the effectiveness of occupational therapist-suggested sensory stimuli on the automatically maintained problem behavior of adults. Specifically, we compared the effects of non-contingent access to sensory stimuli and non-contingent access to highly preferred stimuli on the rate of problem behavior. Results suggested that, relative to highly preferred stimuli, sensory stimuli had either a limited effect on problem behavior, or in some cases, were correlated with increases in problem behavior. This suggests that sensory stimuli may not produce the same automatic stimulation as problem behavior. We will discuss implications for treatment, including methods for better identifying stimuli for use in the treatment of automatically maintained problem behavior.
Date:
December 2023
Creator:
Pelletier, Danielle Renee
System:
The UNT Digital Library
An Analytical Study of the Suite for Violin and Piano (1935), Op. 6, by Benjamin Britten (1913-1976)
The Suite for Violin and Piano, Op. 6 is one of the least-known compositions by Benjamin Britten. It has been considered unfavorably by critics and scholars due to its puzzling mixture of tonal and post-tonal elements. However, this dissertation argues that the suite is composed with a clear tonal framework, and its unique mixed tonal-post-tonal language justifies an in-depth analysis. This analytical study utilizes a linear progression technique - the voice leading produced by passing tones and neighbor notes around focal pitches - to identify tonal areas of the suite.
Date:
December 2023
Creator:
Lee, Hanjun
System:
The UNT Digital Library
Analyzing the Joint Effects of Network and Community Attributes on Network Performance: Evidence from Local Continuum of Care Homeless Service Networks
This dissertation examines the factors and combinations of factors that affect the performance of continuum of care homeless service networks, applying the configurational approach of contingency theory to data sets drawn from federal sources. The study accepts the two key assumptions from the theory: (1) that there are multiple paths to high performance and (2) key conditions have a joint influence on network performance. The data analysis in this study has two parts. The first employs OLS regression to examine the causal relationship between independent variables and the performance of permanent supportive housing (PSH) programs. This study also applies fuzzy set qualitative comparative analysis (fsQCA) to identify multiple combinations of factors that influence the performance of PSH programs. The results identify key factors and multiple combinations of factors that lead to high and low network performance. Federal CoC funding emerges as a core condition for high and low performance, but all relevant conditions can be critical factors depending on how they interact with other relevant conditions. This analysis helps expand the utility of existing contingency theory by using it to explain the dynamic interactions between factors in the context of public service networks. Ultimately, this dissertation confirms that fsQCA can …
Date:
December 2023
Creator:
Kim, Jintak
System:
The UNT Digital Library
Are We Zwisch-ing Yet? An Examination of the Zwischenfach Voice Category and Selected Twenty-First Century American Arias
The German word Zwischenfach often refers to opera roles and singers whose voices lie between the categories of mezzo-soprano and soprano. While the term is not universally accepted as a voice category, Zwischenfach voices and roles are being discussed more openly and with more specificity in collegiate and professional circles. This document includes a discussion on the challenges of categorizing dramatic voices, mezzo-soprano voices, and those who could be considered Zwischenfach, taking into consideration the inherent ambiguity and flexibility within these voice categories. The elements that have led to developmental changes in opera voices and their categories over the centuries provide insight and context on how Zwischenfach has become a term that describes the ambiguity and challenge of classifying opera voices in the twenty-first century. A main focus of this document is a discussion of eleven pieces from twenty-first century American operas which a Zwischenfach singer could consider for auditions and performances. Operas included are: Dead Man Walking by Jake Heggie, The Grapes of Wrath by Ricky Ian Gordon, After Life and Glory Denied by Tom Cipullo, Lysistrata by Mark Adamo, Dinner at Eight by William Bolcom, and Fantastic Mr. Fox by Tobias Picker. My hope is that this document …
Date:
December 2023
Creator:
Taylor, Hilary Grace
System:
The UNT Digital Library
Avian Community Response to Riverby Ranch Restoration Reconstruction
Anthropogenic activities have caused many wildlife spices to decline in populations worldwide. The grassland bird communities are especially being impacted by these land use changes. Breeding success is closely tied to functional habitats for most grassland bird species in North Texas. Restoring these degraded habitats is an important component to aid in conserving wildlife biodiversity. We surveyed the bird population at Riverby Ranch Mitigation site by conducting point count sampling. This site consists of recently restored grassland, wetland, and forested habitat. This research was focused on conducting post restoration monitoring of the bird community in the early succession of the restored habitats. We set out to use the bird community as biomonitors to help assess if the restoration practices could be considered successful. We found that density estimates were more than double at the restored site when comparing to three different references sites under different management practices. This included an unrestored working ranch, a wildlife management area, and a conservation managed prairie site. We found that biodiversity metrics were as high or higher than the reference sites. In addition, we also found that there were more observations of species of high conservation concern present at the restored stie. This research …
Date:
December 2023
Creator:
Boucher, Tessa Katrish
System:
The UNT Digital Library
Bottom-Up Impacts of Grazing Disturbance on Ground-Nesting Bee Assemblages: Do They Dig It?
In my thesis, I examined impacts of nesting and floral resources on ground-nesting bee assemblages at nine ranch sites with differing grazing histories. Because ecological disturbances can strongly affect the availability of foraging and nesting resources over time, I also examined the impacts of grazing history on nesting and floral resources for ground-nesting bees. I sampled bee assemblages, a comprehensive array of vegetation and soil measures, and floral abundance and richness. I used these data to determine (1) the importance of different nesting habitat resources and livestock grazing history for ground-nesting bees and (2) how livestock grazing history influenced the availability of nesting and floral resources. I found that sites with sandier soils had greater abundance and richness of ground-nesting bees, and sites with less compacted soils had greater bee abundance. Contrary to many other studies, the availability of bare ground was not important for ground-nesting bee abundance or richness. Grazing history did not affect any measures of nesting or floral habitat, and had negligible effects on ground-nesting bee abundance, richness, and community composition. My results suggest that the availability of sandier or less compacted soils may be limiting for ground-nesting bee abundance or richness, especially in areas with predominately …
Date:
December 2023
Creator:
Collins, Shannon Marie
System:
The UNT Digital Library
Building a Digital Twin of the University of North Texas Using LiDAR and GIS Data
Digital twins are virtual renditions of the actual world that include real-world assets, connections, activities, and processes. Recent developments in technologies play a key role in advancing the digital twin concept in urban planning, designing, and monitoring. Moreover, the latest developments in remote sensing technology have resulted in accurate city-scale light detection and ranging (LiDAR) data, which can be used to represent urban objects (buildings, vegetation, roads, and utilities), enabling the creation of digital twin of urban landscapes. This study aims to build a digital twin of the University of North Texas (UNT) using LiDAR and GIS data. In this research, LiDAR point clouds are used to create 3D building and vegetation modeling along with other GIS data (bicycle racks and parking areas) in creating a digital twin model. 3D Basemap solutions of ArcGIS Pro and ArcGIS Online Scene Viewer, respectively, are used to create an initial 3D urban model and build the ultimate digital twin of UNT. The emergency management floorplans of UNT buildings are incorporated into the digital twin to increase emergency management efficiency. Moreover, solar power potential for individual buildings at UNT has been estimated using the Digital Surface Model (DSM) and integrated into the digital twin …
Date:
December 2023
Creator:
Bhattacharjee, Shwarnali
System:
The UNT Digital Library
California Public Schools and Employees' Negligence of Supervision on School Property
We live in a culture where school systems are accused of being negligent or at fault for any undesired outcome. This can leave school districts and their employees anxious about potential consequences, regardless if the negligent claim is warranted or not. Therefore, there is a need for all educators to understand their responsibilities to provide a safe learning environment, and this may look different from state to state across the United States. The purpose of this study was to analyze how California state courts have interpreted the concept of sovereign immunity and tort claims filed against California public-school districts and their public-school employees related to negligence of supervision on school grounds. This legal research case study design was guided by the following research question: what are the exceptions to sovereign immunity regarding negligence related to the supervision of students as required by California statute? This study analyzed twelve various cases of California public-school districts and employees involving negligence in supervision claims on school grounds after the 1963 California Tort Claims Act was enacted. Based on the issue, rule, application, and conclusion of the twelve cases, eight were ruled in favor of the plaintiff or appellant, and four cases had final …
Date:
December 2023
Creator:
Gonzales, Manuel Salas
System:
The UNT Digital Library
Climate Injustice and Commodification of Lives and Livelihoods in Southwest Coastal Bangladesh
Just and equitable responses to the disparate impacts of climate change on communities and individuals throughout the world are at the heart of the concept of climate justice. Commodification, in the context of my research, is the process of monetizing nature and livelihoods for the purpose of surplus accumulation and profit maximization. In this study, my aim was to contextualize the concepts of climate injustice, disaster capitalism, and the commodification of lives and livelihoods in the specific setting of disaster vulnerability in southwest coastal Bangladesh. By conducting a case study in Kamarkhola and Sutarkhali regions of southwest coastal Bangladesh, I utilized discourse analysis and content analysis of livelihood interviews, semi-structured interviews, and policy documents to demonstrate the conceptual interrelation among global climate change, climate injustice, disaster capitalism, and capitalist expansion in environmentally precarious areas. I argue that in Southwest Coastal Bangladesh, the vulnerability to disasters stems from a complex and multifaceted layer of social hierarchies and inequalities, entwined with factors such as class and power relations. I also argue that Inequalities in the political, economic, and social realms have a key role in imposing vulnerability on disadvantaged people living in ecologically vulnerable areas. The perpetuation of inequality is sustained by …
Date:
December 2023
Creator:
Keya, Kamrun Nahar
System:
The UNT Digital Library
Collegiate Experiences of Female Undergraduate Students in an Afghan University
Amidst the turbulence of political shifts and the re-emergence of the Taliban, this phenomenological research shines a light on the lived experiences, aspirations, and challenges of female undergraduate students in an Afghan university. Through in-depth, qualitative interviews, this study unravels six pivotal themes shaping their collegiate journey: gender-centric oppression, systemic and structural barriers, academic hindrances, family support, and the motivation to endure and prevail amidst profound adversities, such as enforced gender apartheid and stringent clothing mandates. Within an intersectionality framework, this research not only bridges a critical gap in the literature but also serves as a crucial narrative for global academia and policy-making arenas, underlining the imperative for robust advocacy and policy reforms. The stark findings and nuanced insights gleaned from this study underscore the imperative to foster gender equality and educational access, whilst advocating fervently for the re-establishment of inclusive and supportive educational environments for all in Afghanistan.
Date:
December 2023
Creator:
Juya, Masoud
System:
The UNT Digital Library
The Competency Pipeline: Examining the Association of Doctoral Training with Early Career Outcomes
Participants from earlier nationwide studies on predictors of internship match were contacted 7-10 years after obtaining their doctoral degree to gather additional data concerning their attained early career competencies and benchmarks (e.g., scores on the national licensing exam). In this sample (N = 190), licensure exam scores were significantly positively associated with scores obtained on the Graduate Record Examination (GRE), family of origin socioeconomic status, and student debt load. However, obtained licensure scores were not found to be significantly associated with any pre-doctoral training variables (e.g., intervention/ assessment hours, number of integrated reports, number of publications, rank order of matched internship site) or most post-doctoral early career activities. Weak positive associations between licensures scores and engaging in teaching / supervision / consultation services were observed. Few self-reported early career competencies were found to be weakly positively associated with scores on the national licensing exam (i.e., integrity, seeking supervision, scientific mindedness, evidence-based practice). Significantly inverse associations were found between national licensing exam scores and self-reported competencies in the areas of management and systems change. Findings are discussed and implications for the national licensing exam considered.
Date:
December 2023
Creator:
Ortiz, Andrea
System:
The UNT Digital Library
A Comprehensive Investigation of Photoinduced Electron Transfer and Charge Transfer Mechanisms in Push-Pull Donor-Acceptor Systems: Implications for Energy Harvesting Applications
Donor-acceptor systems exhibit distinctive attributes rendering them highly promising for the emulation of natural photosynthesis and the efficient capture of solar energy. This dissertation is primarily devoted to the investigation of these unique features within diverse donor-acceptor system typologies, encompassing categories such as closely covalently linked, push-pull, supramolecular, and multi-modular donor- acceptor conjugates. The research encompasses an examination of photosynthetic analogs involving compounds such as chelated azadipyromethene (AzaBODIPY), N,N-dimethylaminophenyl (NND), phenothiazine (PTZ), triphenylamine (TPA), phenothiazine sulfone (PTZSO2), tetracyanobutadiene (TCBD), and expanded tetracyanobutadiene (exTCBD). The strategic configuration of the donor (D), acceptor (A), and spacer elements within these constructs serves to promote intramolecular charge transfer (ICT), which are crucial for efficient charge and electron transfer. The employment of cutting-edge analytical techniques, such as ultrafast transient absorption spectroscopy, is integral to the study. Furthermore, a comprehensive suite of analytical methodologies including steady-state UV-visible absorption spectroscopy, fluorescence and phosphorescence spectroscopies, electrochemical techniques (including cyclic voltammetry and differential pulse voltammetry), spectroelectrochemistry, and density functional theory calculation (DFT), collectively contribute to the comprehensive characterization of push-pull donor-acceptor systems, with a particular emphasis on their potential as highly effective solar energy harvesting application.
Date:
December 2023
Creator:
Alsaleh, Ajyal Zaki
System:
The UNT Digital Library
Conditional Disclosure of Secrets and Storage over Graphs
In the era of big data, it is essential to implement practical security and privacy measures to ensure the lawful use of data and provide users with trust and assurance. In the dissertation, I address this issue through several key steps. Firstly, I delve into the problem of conditional secret disclosure, representing it using graphs to determine the most efficient approach for storing and disclosing secrets. Secondly, I extend the conditional disclosure of secrets problem from a single secret to multiple secrets and from a bipartite graph to an arbitrary graph. Thirdly, I remove security constraints to observe how they affect the efficiency of storage and recovery. In our final paper, I explore the secure summation problem, aiming to determine the capacity of total noise. Throughout the dissertation, I leverage information-theoretic tools to address security and privacy concerns.
Date:
December 2023
Creator:
Li, Zhou
System:
The UNT Digital Library
"Creature from the Unconscious"
Creature from the Unconscious is a reflexive genre hybrid film that follows the process of the director's journey of navigating the process of self-acceptance and self-love in the wake of trauma.
Date:
December 2023
Creator:
Powell, Madison Keely
System:
The UNT Digital Library
Cross-Conjugation Effects on Fused β, β'–π–Extended Porphyrins
Cross-conjugation in molecules has been seen in nature for many years but was not pursued due to the difficulty of their synthesis and their lack of stability. Recently, it has become more interesting due to the rise of molecular electronics. Linear conjugation serves well as the wires to conduct electrons, but molecular electronics are made up of more than just wires. Molecules are needed that possess an on/off switch that can allow or deter conduction. Cross-conjugated systems show promise in their ability to be turned on or off from external stimuli. Pentacene quinone is a well-known cross-conjugated molecule that already shows promise in the field of molecular semiconductors. By synthetically fusing the pentacene quinone to the β, β' positions of a porphyrin, it has been shown that both the solubility and stability have been greatly improved. This has allowed us to pursue functionalization of the quinone moiety. Several new cross-conjugated pentacene quinone fused porphyrin systems were synthesized and studied. It was found that cross-conjugated platinum porphyrins show enhanced fluorescence, and phosphorescence that shifts toward the Near IR. Additionally, strong electron withdrawing groups show potential in charge transfer, and a lower HOMO to LUMO gap, while mildly withdrawing groups have a …
Date:
December 2023
Creator:
Washburn, Spenser L.
System:
The UNT Digital Library
Cross-Pollinating Culturally Sustaining Pedagogies and Systemic Functional Linguistics in English as a Second Language (ESL) Classrooms
This exploratory case study research was conducted with a view to exploring how teachers teaching emergent bilingual students in ESL programs can enact the principles of culturally sustaining systematic functional linguistics (CS SFL), such as critical centering, historicizing, curricularizing, teaching and learning cycle (TLC), and semantic waving in their classrooms. Two middle school teachers participated in the study and used CS SFL principles to teach their emergent bilingual students. I gathered data for the study through non-participatory observations, semi-structured interviews, informal talks with the teachers, usually right after their classes, and artifacts from teachers and students. The thematic analysis of the data demonstrated that teachers could recognize their students' ways of knowing and being by (a) translanguaging between English and Spanish seamlessly in their classrooms; (b) centering their students' lifeways, prior knowledge, and lived experiences by making them the parts of their curricula; (c) using TLC for creating dialogic interactions between teachers and students and among students; (d) positioning their students through strength perspectives; and (e) using multimodal and multi-semiotic means of communication so that their students can understand their content area knowledge and express their ideas even if their English language is emerging. The teachers faced tensions about whether …
Date:
December 2023
Creator:
Rana, Lal Bahadur
System:
The UNT Digital Library
Cyber Addiction and Information Overload and Their Impact on Workplace Productivity
The research examines the relationship between cyber addiction (excessive use of the Internet, CA), information overload (IO), and assesses their impact on workplace productivity. A multi-methods approach is used employing the Internet Addiction Test (IAT) and a quantitative survey design to assess and test the stated hypothesis. The study used random sampling methods targeting 150 respondents from different information technology departments of various organizations. The study hypothesizes that CA and IO have a reciprocal association, which adversely affects workplace productivity and employee performance. From the findings, IAT scores increase with an associated possibility of reporting burnout, fatigue, and other components associated with CA and IO. Also, CA and IO were significantly correlated, as evaluated by the chi-square test, although the same approach did not yield significant associations between CA and perceived internet dependence. Other findings CA components, such as social media use, significantly associated with task postponement and burnout. As well, CA affected IO with substantial impacts on workplace productivity. The paper highlights managerial aspects that organizations should consider in optimizing the output of their staff. Recommendations include wellness programs, altering the leadership and management styles, and sensitizing the employees on the adverse effects caused by the two variables.
Date:
December 2023
Creator:
Alboulayan, Moneerah Abdulhameed M.
System:
The UNT Digital Library
Decoding Fantasy: An Analysis of Paquito D'Rivera's "Caribbean Berceuse" (2021)
Written for and featuring the Barcelona Clarinet Players, Caribbean Berceuse (2021) is Paquito D'Rivera's (b.1948) first composition for wind band. Along with idiosyncratic expectations of fusing jazz and classical elements according to D'Rivera's oeuvre, the title implies extramusical associations in the composition. This analysis demonstrates how extramusical associations interact with thematic development by using five codes of meaning from Roland Barthes's (1915–1980) S/Z (1970), which was first applied to music by Patrick McCreless. In addition to D'Rivera's cultural references, this composition involves musicians from many different cultures and backgrounds: the Barcelona Clarinet Players of Spanish heritage, Paquito D'Rivera of Cuban heritage, and the North Texas Wind Symphony under the direction Eugene Migliaro Corporon as an American melting pot. My analysis demonstrates how D'Rivera incorporates shared experiences of a lullaby as an access point for listeners. Our experience of falling asleep creates dichotomous structures of reality and fantasy, of time and memory, and sometimes of a restless lullaby among others. Roland Barthes places the most importance on these extrinsic dichotomous structures as deeper meanings of referential associations. He names this symbolic code. Although McCreless places less importance on symbolic code as correlating to music, my analysis will demonstrate how the interaction …
Date:
December 2023
Creator:
Truan, Robert Michael
System:
The UNT Digital Library
Degradation Mechanisms and Dynamics of Silicon Telluride: A Guide to the Effective Fabrication and Characterization of Silicon Telluride-Based Devices
Silicon telluride (Si2Te3) and many other tellurium containing compounds show emergent Raman peaks located at ~120 cm-1 and ~140 cm-1 as they age. The origin of these two emergent peaks is controversial in the literature and has been attributed to myriad causes such as the intrinsic Raman modes of the telluride materials, surface oxidation, defects, double resonances, and tellurium precipitates. The controversial nature of these peaks has led to the misidentification of highly degraded materials as pristine and to the misinterpretation of changes in Raman spectra. For the first time, quality thin film and bulk crystals of Si2Te3 are grown using a chemical vapor deposition (CVD) process. We then present a comprehensive and multimodal study of various Si2Te3 samples and find that the two emergent Raman peaks originate from tellurium nano-crystallites formed in the degraded surface layers of Si2Te3. The formation of the tellurium nano-crystallites are shown to be a result of a hydrolysis process in which Si2Te3 reacts with atmospheric water vapor. The challenges involved in the fabrication of Si2Te3 based devices are also discussed and ways in which degradation can be either prevented or reversed are demonstrated. Finally, we present preliminary data which shows promising low voltage switching …
Date:
December 2023
Creator:
Hathaway, Evan Allen
System:
The UNT Digital Library
Design and Development of a Paper Spray Air Sampling Device for Use in Clinical, Defense, and Environmental Applications
Environmental monitoring is becoming increasingly important, primarily in urban areas due to the concentrated levels of human activities. The air sampling device presented is a novel method to sample air which harnesses the power of paper spray ionization paired with the intrinsic advantages of mass spectrometry such as high sensitivity, high selectivity, high throughput, and the ability to monitor multiple compounds at once.
Date:
December 2023
Creator:
Murillo, Wilbert Alberto
System:
The UNT Digital Library