Digital Commons Network^™

Laser Spectroscopy Investigations Of Jet-Cooled Metal-Containing Free Radicals., Anam Chandra Paul

Electronic Theses and Dissertations

Metal-containing free radicals are important intermediates in metal-surface reactions and the interactions between metals and organic molecules. Among metal-containing free radicals, monovalent derivatives of alkaline earth metals have been extensively investigated by using spectroscopic techniques in a gas phase, mainly in Broida ovens or under supersonic-jet-cooled conditions. In the present study, the results of performed spectroscopic investigations of both metal-containing monoalkoxides (CaOR) and metal oxides (MO) radicals have been reported. Laser-induced fluorescence (LIF) and dispersed fluorescence (DF) spectra of the electronic transition of the calcium CaOR radicals have been obtained under jet-cooled conditions. Complete active space self-consistent field (CASSCF) and …

Exploratory Learning Activities In The Physics Classroom: Contrasting Cases Versus A Rich Dataset., Campbell Rightmyer Bego

Electronic Theses and Dissertations

In exploratory learning, students engage in an exploration activity on a new topic prior to instruction. This inversion of the traditional tell-then-practice order has been shown to benefit learning outcomes, especially conceptual knowledge and preparation for future learning, but not always. In three studies, the current work examines whether the type of exploration activity impacts learning mechanisms and outcomes, on the topic of gravitational field in undergraduate physics classrooms. Activities using either contrasting cases (CC) or a rich dataset (RD) are compared in two instructional orders, explore-first (EF) and instruct-first (IF). Learning outcomes measured procedural knowledge, conceptual knowledge, and performance …

Laser Spectroscopy Investigations On Molecular And Free Radicals Dynamics., Hamzeh Telfah

Electronic Theses and Dissertations

Studying molecular dynamics and chemical kinetics is important to understand the chemical behavior of renewable energy sources. Laser spectroscopy techniques are powerful tools for the identification and diagnosis of such processes. In this dissertation, using our laser spectroscopy techniques, biofuels and solar energy were targeted as renewable energy sources study. We have studied the ultrafast exciton dynamics for a series of methylammonium lead bromide (CH3NH3PbBr3) nanostructures, nanocrystals (NCs, 0D), nanowires (NWs, 1D), and nanoplatelets (NPs, 2D) as a promising solar energy materials.1-2 Aided by analysis of UV−visible absorption and photoluminescence spectra, features in the transient absorption (TA) spectra are assigned …

Laser Spectroscopic Investigations Of Organic Alkoxy And Peroxy Radicals., Md Asmaul Reza

Electronic Theses and Dissertations

Understanding the mechanism of combustion reactions is key for advancing internal combustion engine design, improving the efficiency of ignition chemical reactions, and reducing pollutant formation. In order to model the extremely complicated chemical kinetics of combustion processes, it is critical to detect and identify transient reactive chemical intermediates, particularly free radicals. Hence, it needs to be fully understood the gas-phase chemistry of organic compounds in the lower atmosphere. Over the past fifty years, parallel advancement in observational, experimental, and theoretical techniques, tremendous strides have been made in our understanding of the role of organic compounds in the atmosphere. Combustion chemistry …

Brokering Words And Work: Complexities Of Literacy Sponsorship In The Oilfields Of South Texas., Jennifer L. Marciniak

Electronic Theses and Dissertations

This research is an investigation of workforce recruitment language as the “leading edge” of literacy sponsorship as it pertains to blue-collar rig and service workers in the South Texas oilfields. Using Deborah Brandt’s Literacy in American Lives as a framework for this study, I conducted interviews with 10 rig and service workers and labor market intermediary administrators about the perceptions and expectations of literacy use in oilfield work. My inquiry begins by first learning about workers’ experiences with recruitment into the industry. Then, to understand more about how the industry communicates literacy expectations to these workers, I look at recruitment …

Perceptions Of Restorative Practices Among Black Girls: Talking Circles In An Urban Alternative Middle School., Vanessa Marie Mcphail

Electronic Theses and Dissertations

Research suggests that Restorative Justice approaches have shown promise in terms of their impact on school climate, student behavior, and relationships. The purpose of this study is to explore Black female students’ perceptions of Restorative Practice (RP) talking circles at an alternative school. The study examined literature on Zero Tolerance, School Discipline Disparities, African American Female students, Intersectionality, Restorative Justice, and Alternative Schools. A qualitative case study method was used for this study, drawing from two sources: (a) face-to-face interviews and (b) observations of the Black female students who attend the alternative school and participate in the talking circles. Analyses …

Development And Characterization Of A Biopolymer Direct-Write Process For 3d Microvascular Structures Formation., Xiaoming Fan

Electronic Theses and Dissertations

Engineering of bulk tissues has been limited by the lack of nutrient and waste exchange in these tissues without an adjacent capillary network. To produce microvasculature, a scaffold must be produced that provides temporary mechanical support and stimulate endothelial cell adhesion, growth, and morphogenesis into a vessel. However, current well-established techniques for producing microvasculature, such as electrospinning, are limited since they lack both the precision to control fiber placement in three-dimensional space and the ability to create fiber networks with predefined diameters to replicate the physiological microvascular progression from arteriole to capillary to venule. Our group has developed a “Direct-write” …

Oxygen Deficient Perovskites: Effect Of Structure On Electrical Conductivity, Magnetism And Electrocatalytic Activity., Ram Krishna Hona

Electronic Theses and Dissertations

The present thesis deals with the synthesis and study of the physico-chemical properties of perovskite based oxide materials. Several novel oxygen deficient perovskites (ODP) have been synthesized by conventional solid state synthesis method. The novel compounds are CaSrFe₂O_6-δ, CaSrFeCoO_6-δ, Ca₂Fe_1.5Ga_0.5O₅, CaSrFeGaO₅ and BaSrFe₂O₅. Their magnetic, charge transport and electrocatalytic properties have been studied. Structural effect on electrical conductivity, magnetic and electrocatalytic properties have been studied in some series of ODPs. CaSrFe₂O_6-δ, CaSrFeCoO_6-δ, Ca₂Fe …

Effects Of A Writing Instructional Package For Students With Moderate Intellectual Disability., Beth Newberry Gurney

Electronic Theses and Dissertations

The development of writing skills is one of the most complex competencies that students are expected to master (Saddler, 2013). Limited research has been conducted on the acquisition of writing skills for students with moderate and severe intellectual disability. Even fewer studies have examined the acquisition of sentence construction skills. The current study examines the effects of a writing instructional package using peer tutoring, response prompting, and sentence frames to teach students with moderate intellectual disability to construct sentences related to adapted grade-level social studies content. Four seventh grade students without disabilities were trained to implement the writing instructional package …

Stability And Reactivity Analysis Of Single Metal And Bimetallic Nanostructures By Anodic Stripping Voltammetry., Dhruba Kumar Pattadar

Electronic Theses and Dissertations

This dissertation has two main themes. The first involves studies aimed at developing anodic stripping voltammetry (ASV) as an analytical tool to characterize metal nanoparticles (NPs), with a focus on the size and aggregate structure of single metal NPs and the composition and atomic arrangement of bimetallic NPs. The second main theme involves studies that use ASV and electrochemical surface area-to-volume (SA/V) measurements to study the unique reactivity and transformations of single metal and bimetallic NPs. The transformations involve size and composition changes in response to ozone and electrochemical potential. Reactions involve size dependent galvanic exchange and electrocatalytic activity. The …

Investigating Administrators’ Resistance To Implementing Restorative Practices, Beri Deister

Electronic Theses and Dissertations

In this case study, the researcher investigated the barriers to school administrators’ implementation of restorative practices as a management approach to student behavior. Based on the claim that restorative practices is a promising alternative to exclusionary disciplinary placements for changing behavior, the researcher used an emergent explanatory mixed methods design to better understand administrators’ resistance to change despite overwhelming evidence that exclusionary disciplinary practices are the primary contributors to national trends in disciplinary disproportionality and institutional discrimination. The researcher identified and analyzed barriers to create recommendations for addressing administrators’ resistance through organizational change strategies using systems theory.

The Potential Of Radium-224 As A Tracer Of Timescales Of Gulf Of Mexico Crude Oil Exposure To The Marine Environment, Matthew T. Kurpiel

Electronic Theses and Dissertations

Petroleum pollution in the marine environment can be deleterious to coastal and marine ecosystems and can have sustained effects for years. While oil slicks on the surface of the ocean are tracked with relative ease using satellite-based technology, deep sea, neutrally-buoyant hydrocarbon plumes remain exceedingly difficult to track. We provide evidence for the utility of Ra-224 as a potential hydrocarbon tracer to determine the marine exposure time of crude oil. We employed time course incubations to constrain a time dependent Ra-224 release signature and tested a variety of timescales, temporal resolutions, oil sources, seawater, and experimental treatments to determine potential …

Utilization Of Bedside Shift Report To Decrease Medication Errors On A Cardiac Progressive Care Unit, Maud Millicent Acquah Nelson

Electronic Theses and Dissertations

Medication errors cause millions of deaths every year in the United States. Miscommunication during the transition of care accounts for the highest number of such errors. The lack of patientinclusion in information exchange among nurses during the change of shift prevents reliable and accurate information exchange and threatens patients’ safety. Inadequate transfer of patient information from one nurse to the other on a hospital unit can cause unfair irreversible harm to the patient and even death. Orlando’s (1961) dynamic nurse-patient relationship theory explained the interdependent relationship between the nurse and the patient in achieving excellent treatment outcomes. This descriptive, inferential …

Machine Learning-Based Models For Assessing Impacts Before, During And After Hurricane Events, Julie L. Harvey

Electronic Theses and Dissertations

Social media provides an abundant amount of real-time information that can be used before, during, and after extreme weather events. Government officials, emergency managers, and other decision makers can use social media data for decision-making, preparation, and assistance. Machine learning-based models can be used to analyze data collected from social media. Social media data and cloud cover temperature as physical sensor data was analyzed in this study using machine learning techniques. Data was collected from Twitter regarding Hurricane Florence from September 11, 2018 through September 20, 2018 and Hurricane Michael from October 1, 2018 through October 18, 2018. Natural language …

Factors Influencing Faculty Use Of Screencasting For Feedback, Berlin Fang

Electronic Theses and Dissertations

This study explored faculty concerns in using screencasting to give feedback, why they choose to adopt it, and what training and support would benefit them in the adoption of such a method. This is a single embedded case study using a stages of concern questionnaire, semistructured and open-ended interviews, as well as media comment reviews as data collection methods. Some 21 professors from a southwestern private university participated in the research, representing 51 potential participants who have been exposed to screencasting for feedback through software ownership, training, or coaching. After the completion of this questionnaire, 16 participants were interviewed in …

Evaluating The Relationships Between Science Class Success And Math Placement In High School, Tila Hidalgo

Electronic Theses and Dissertations

In order for students to perform well in science, they need opportunities to develop formal reasoning. Teachers in a private school in Latin America noted that students who had not yet completed Algebra I were struggling in a 9th-grade chemistry course more than their classmates who had completed Algebra I. The purpose of this causal, comparative action research was to determine if math placement was key to supporting student success in science. Data on achievement, as indicated by final exam scores in math, science, and English, were used from the cohort of students enrolled in 9th grade in 2015 and …

Coarse Root, Forest Litter, And Soil Organic Matter Contributions To Carbon Sequestration In Loblolly Pine (Pinus Taeda) Plantations In East Texas, William Wedge

Electronic Theses and Dissertations

Understanding ecosystem carbon dynamics is of increasing importance with atmospheric carbon dioxide (CO2) concentrations on the rise. Land management strategies, such as land use conversion, effect ecosystem carbon cycling dynamics and can alter the quantity of carbon sequestered in vegetation and soils. In East Texas and much of the southern United States, there has been a trend of converting marginal pastureland into loblolly pine (Pinus taeda) plantations. This afforestation, like all other land use conversions, leads to a redistribution of carbon in vegetation and soil carbon sinks. In 2003, five marginal pasturelands in East Texas were afforested with loblolly pine …

2-D And 3-D Temporal Modeling Of Solute Migration Through Low Permeable Media Using Electrical Resistivity, Nacogdoches County, Texas, Kaleb Henry, Kevin W. Stafford, Wesley Brown, Melinda Faulkner, Matthew Mcbroom

Electronic Theses and Dissertations

The Reklaw Formation is the upper bounding unit for the Carrizo-Wilcox Aquifer throughout the Gulf Coastal Plain of East Texas and consists of low permeability, glauconite-rich strata that isolate semi-confined portions of the aquifer system from potential contaminants. Electrical resistivity methods were employed within a forested watershed in Nacogdoches County, Texas to characterize solute transport. 2-D and 3-D temporal resistivity data collected with an AGI SuperSting (R8/IP) were processed with AGI Earthimager 2D/3D software for inversion modeling. Data were collected over 135 days within a 14 X 26 meter (46 X 85 feet) gridded survey at 15-day intervals after initiation …

Identifying Risk Factors Related To Premature Birth Through Binary Logistic And Proportional Odds Ordinal Logistic Regression, Clayton Elwood

Electronic Theses and Dissertations

Premature birth has been identified as the single greatest cause of death worldwide in children under the age of five. This thesis will implement binary logistic regression and proportional odds ordinal logistic regression to predict different levels of premature birth and identify associated risk factors. The models will be built from the Center for Disease Control and Prevention's 2014 Vital Statistics Natality Birth Data containing nearly 4 million live births within the United States. Odds ratios and confidence intervals on risk factors were produced utilizing binary logistic regression.

A Quantitative Study Of Drug Recrystallization In Drug-In-Adhesive Transdermal Patches Using Vibrational Spectroscopy, Yi Li

Electronic Theses and Dissertations

Drug-in-adhesive (DIA) transdermal patches are an important type of transdermal drug delivery system (TDDS). The drugs used in the DIA system are frequently present in metastable forms, such as amorphous solids or supercooled liquids. These drug states are thermodynamically unstable and tend to undergo recrystallization. Recrystallization of the active pharmaceutical ingredient can adversely affect the efficacy of transdermal products. This dissertation demonstrates a systematic approach to quantify the crystalline content of the API in DIA systems. This approach uses a novel method of preparing calibration standards and a spectroscopic method to reliably predict crystalline content in DIA patches. Spectroscopic tools, …

Score Improvement Comparison From Psat To Sat Between Two Schools, Salvatore Brusco

Electronic Theses and Dissertations

The score a student earns on the PSAT is a predictor for what they earn on the SAT. Based on a student's PSAT score, we construct a Bayesian model to predict, with 95% certainty, what they will earn on their SAT. Furthermore, we explore differences in this prediction between two high schools in the same district; and ask whether the probability of improvement from the PSAT to the SAT is consistent between these two schools.

Emergency Department Nursing Psychological Care (Early Crisis Intervention) For Adult Victims Of Violent Crime: A Quantitative Study, Barbara Conn

Electronic Theses and Dissertations

Recognition of the significance of early interventions and the importance of addressing psychological trauma for the victim of violence is of utmost importance for quality of life and the victim’s future. The serious impact of psychological trauma on victims of violent crime supports further study to determine whether Emergency Department (ED) nurses assess this trauma and initiate early interventions and referral for ongoing psychological care. Nursing care, assessment and early intervention with victims of violent crime was the focus of this dissertation study.

A quantitative study, with a non-experimental, descriptive design employed retrospective chart reviews to determine whether ED nurses …

Triple Functionalization Of Titanium Aluminum Vanadium For Orthopedic Implant Applications, Ashley Blystone

Electronic Theses and Dissertations

Orthopedic implant surgeries are on the rise in the United States, with well over a million surgeries performed annually. Common materials used for these applications include titanium and its alloy, titanium aluminum vanadium (Ti-6Al-4V). Ti-6Al-4V is chosen for this application due to its mechanical strength and corrosion resistance. However, Ti-6Al-4V does not support osseointegration and is susceptible to bacterial colonization. Therefore, these implants suffer from aseptic loosening and infection, necessitating removal and replacement. Revision surgery and treatment is financially burdensome and taxing on the patient. Current approaches focus on modifying the surface of Ti-6Al-4V through a variety of means to …

Using An Extended Broken Symmetry Approximation To Characterize Structure And Spectroscopic Properties Of 2fe-2s Clusters, Ashlyn M. Koval

Electronic Theses and Dissertations

Iron-sulfur proteins perform a wide variety of biological functions that assist in mediating protein function via electron transfer reactions. The Rieske and mitoNEET iron-sulfur clusters have been shown to undergo proton coupled electron transfer facilitated by a histidine ligand. The protonation state of the histidine residue is key to understanding the mechanism of proton coupled electron transfer. This work reports a study of the 2Fe-2S ferredoxin, Rieske, and mitoNEET clusters using the extended broken symmetry approximation. Calculations were performed on the ferredoxin cluster to establish appropriate methodologies. Calculations were then performed for Rieske and mitoNEET clusters to suggest experiments capable …

Reconstructing A Centennial-Scale Extreme Paleoflood History Of The Pee Dee River Using Oxbow Lake Sediments, Nicholas William Conway

Electronic Theses and Dissertations

Extreme river floods are the key force shaping floodplain landscape and a major process delivering sediment, pollutants, and nutrients to coasts. These devastating natural hazards pose concerns about potential change of extreme flood occurrence in the face of climate change. However, accurately assessing the impact of anthropogenic climate change and natural climate modes on the intensity and frequency of extreme flooding relies on multi-century discharge records. Unfortunately, instrumental records are relatively short (often <100 years) and overlap with times of dam and reservoir construction. Oxbow lakes, ubiquitous in the floodplains of alluvial rivers, may preserve an archive of extreme flood at centennial timescales as they capture coarser channel sediments transported by intensified river flows. This study has identified signals of extreme floods in oxbow lake sediments and established a timeline of past flooding events to evaluate change(s) in flood hazard near the Pee Dee River (PDR), South Carolina. Laser diffraction grain-size analysis and X-ray computed tomography (CT) scanning were performed on a ~2-m long piston core (SBL2) to identify event layers of extreme floods. CT images reveal high-density laminations and corresponding coarser shifts of grain size are interpreted as flood layers. A robust age-depth model was established for SBL2 using multiple independent age controls (C14, optically stimulated luminescence, Pb210/C137, and historical event tie-points). End-member modelling analysis was performed to identify a coarse component of the grain-size data used as a proxy of extreme flood. A linear relationship between end-member modelling results and measured discharge was established for the last 80 years and applied to the older part of the core yielding peak discharge estimates back to ca. AD 1840. This analysis identifies abrupt shifts in grain size resulting from dam construction, droughts, and local geomorphic changes to the river system. A multidecadal trend in the frequency of extreme floods is present in the PDR system, controlled by Pacific Decadal Oscillation. The most extreme peak annual discharges of the PDR occurred between AD 1870-1900 from the combined interaction of increased tropical cyclone activity with intensified land use for agricultural purposes. Peak annual discharges of the PDR seem to have decreased through time since flood control damming was completed in AD 1962.

The Role Of A Permeable Sand Column In Modifying Tidal Creek Geochemistry And Land-Derived Inputs To The Coastal Ocean, Nicholas Anthony Legut

Electronic Theses and Dissertations

The impairment of regional water quality in Long Bay is an episodic occurrence that has been documented for over a decade. According to one explanation, the occurrence of these events is hypothesized to be the combination of local, terrestrially derived inputs and water-column stratification in the nearshore zone. A portion of these inputs may discharge as surface run-off through estuaries ending in sandy transitional environments termed "swashes". An investigation into the fate of land-derived materials through swashes utilize a linear conservative mixing model to describe the non-conservative behavior of materials in the overlying water and pore-water. This model relies on …

A First-Year Teacher’S Implementation Of Short-Cycle Formative Assessment Through The Use Of A Classroom Response System And Flexible Grouping, Adrienne Irving Dumas

Electronic Theses and Dissertations

As teachers, we are tasked with ensuring that our students are equipped with the skills necessary to not only perform with proficiency on local, state and national assessments, but also to provide our students with opportunities to develop confidence and competence as learners of mathematics through meaningful, challenging and worthwhile activities. As such, many teachers have turned to technology and cooperative groups as staples in the classroom. The purpose of this study was to understand how one first-year teacher implemented what she was taught in her undergraduate coursework in teaching two specific units of instruction in two sections of high …

Allee Effects Introduced By Density Dependent Phenology., Timothy James Pervenecki

Electronic Theses and Dissertations

We consider both the nonspatial model and spatial model of a species that gives birth to eggs at the end of the year. It is assumed that the timing of emergence from eggs is controled by phenology, which is density dependent. In general, the solution maps for our models are implicit; When the solution map is explicit, it is extremely complex and it is easier to work with the implicit map. We derive integral conditions for which the nonspatial model exhibits strong Allee effect. We also provide a necessary condition and a sufficient condition for the existence of positive equilibrium …

Apartment Residents' Understanding Of And Satisfaction With Water Savings Devices, David Farmer

Electronic Theses and Dissertations

As the human population increases, the way we use and manage our supply of drinking water becomes even more important. The purpose of this study was to determine residents’ satisfaction level of and performance rating of new water savings devices installed in their apartments. Specifically the investigation focused on ratings of shower heads, kitchen faucet aerators, bath faucet aerators, and fill valve and flapper systems.

This quantitative survey included residents at 4 apartment complexes in Tennessee using a paper questionnaire (N = 626). The participants were grouped by age, ethnicity, gender, and whether or not they had experienced both nonrestrictive …

Synthesis, Characterization And Biological Evaluation Of Novel (S,E)-11-[2-(Arylmethylene) Hydrazono] Pyrrolo [2,1-C] [1,4] Benzodiazepine Derivatives, David Mingle

Electronic Theses and Dissertations

Pyrrolo [2,1-c] [1,4] benzodiazepine (PBD) is a class of natural products obtained from various actinomycetes which have both anti-tumor and antibiotic activities and can bind to specific sequences of DNA. PBD-dilactam was initially produced using isatoic anhydride and (L)-proline which was then converted to the PBD-thiolactam using Lawesson's reagent. Reaction of thiolactam with hydrazine in ethanol afforded PBD-11-hydrazinyl. Condensation of 11-hydrazinyl PBD with aldehydes possessing various substitutions was performed to obtain (S,E)-11-[2-(arylmethylene) hydrazono] pyrrolo [2,1-c] [1,4] benzodiazepine derivatives. ¹HNMR, ¹³C-NMR, DEPT, IR, GC-MS and X-ray crystallography were used for the characterization. Inhibition activity of the products …