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University of Mississippi

Electronic Theses and Dissertations

2019

Articles 1 - 30 of 49

Full-Text Articles in Physical Sciences and Mathematics

The Synthesis Of New Donor-Sigma-Acceptor Compounds As Potential Current Rectifiers, Trey Gautier Vaughan Jan 2019

The Synthesis Of New Donor-Sigma-Acceptor Compounds As Potential Current Rectifiers, Trey Gautier Vaughan

Electronic Theses and Dissertations

The zwitterionic D-σ-A’s are characterized by having an anionic donor, a cationic acceptor, an intervening sigma-bond bridge, and an aliphatic tail. The aliphatic tail is of such length as to impart greater solubility in organic solvents since the formal charges on the donor and acceptor lead to poor solubility. Additionally, the aliphatic tail is required for Pockels-Langmuir deposition to facilitate the favorable van der Waal’s packing when combined to form dense monolayer registries. These monolayers may then be suitable for measuring the bulk electrical properties.

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The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell Ladouceur Jan 2019

The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell Ladouceur

Electronic Theses and Dissertations

The Medicine Hat Block (MHB) is one of the core cratonic elements that amalgamated in the Paleoproterozoic to form Laurentia. However the role of the MHB in the formation of Laurentia is poorly constrained due to virtually all of the MHB being concealed by Proterozoic and younger supracrustal sequences limiting availability of data. The primary sources of samples from the MHB are 1) xenoliths of variable metamorphic grade including gneisses amphibolites and meta-plutonic rocks collected from Eocene volcanic rock; and 2) similar lithologies recovered from boreholes that penetrate to the MHB basement. Previous work on samples from the MHB yielded …

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A Computational Approach To Predicting And Understanding New Psychoactive Substances (Nps) For Developing A Database For State And Federal Crime Laboratories, Caroline Amelia Spencer Jan 2019

A Computational Approach To Predicting And Understanding New Psychoactive Substances (Nps) For Developing A Database For State And Federal Crime Laboratories, Caroline Amelia Spencer

Electronic Theses and Dissertations

The object of this dissertation was to use a computational approach to predict and understand new psychoactive substances (NPS) to develop a database for state and federal crime. The primary scope of the dissertation was to better understand the interactions that take place between new psychoactive substances and their corresponding receptors. Through analysis of the interactions between the amino acids within the receptors and the NPS an understanding into the pharmacology and toxicology of these drugs can be gained. NPS such as synthetic cannabinoids fentanyl and its analogs and kratom have become more problematic for both state and federal crime …

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Intramoleculer Hydrogen Bonding In Epoxide, Thiirane, Aziridine And Phosphirane Containing Cyclopentanols, Ben Edward Smith Jan 2019

Intramoleculer Hydrogen Bonding In Epoxide, Thiirane, Aziridine And Phosphirane Containing Cyclopentanols, Ben Edward Smith

Electronic Theses and Dissertations

A recent computational analysis of the stabilizing intramolecular OH· · · O contact in 1,2-dialkyl-2,3-epoxycyclopentanol diastereomers has been extended to thiiriane, aziridine and phosphirane analogues. Density functional theory (DFT), second-order Møller-Plesset perturbation theory (MP2) and CCSD(T) coupled-cluster computations with simple methyl and ethyl substituents indicate that electronic energies of the cis isomers are lowered by roughly 3 to 4 kcal mol−1 when the OH group of these cyclopentanol systems forms an intramolecular contact with the O, S, N or P atom on the adjacent carbon. The results also suggest that S and P can participate in these stabilizing intramolecular interactions …

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A Study To Regioselectively Access Fluorinated Triazoles And Isoxazoles, Sweta Adhikari Jan 2019

A Study To Regioselectively Access Fluorinated Triazoles And Isoxazoles, Sweta Adhikari

Electronic Theses and Dissertations

The objective of the thesis is to develop regioselective methods for mono-fluorination of disubstituted triazoles, both 1,4- and 1,5-regioisomer, and isoxazoles. These strategies focus on one-pot direct access to final mono-fluorinated triazoles and isoxazoles. Eventually, these fluorinated substrates will be screened against various biological targets. Similarly, the optimization study of a regioselective method to generate 5-fluoro-1,4-disubstituted triazole was conducted. This reaction also utilized 1,3-dipolar cycloaddition to synthesize fluorinated triazole. However, difluoroalkene was used as a synthetic equivalent of fluoroalkyne for this method. This resulted into the inversion of polarity affording a different regioisomer. Here, fluoronitroalkene was identified as a synthetic …

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Geographic Variations Of Sound Channel Axis In The Global Ocean, Mukunda Kumar Acharya Jan 2019

Geographic Variations Of Sound Channel Axis In The Global Ocean, Mukunda Kumar Acharya

Electronic Theses and Dissertations

Sound signals are used for imaging and communication in the ocean. Underwater sound speed has a minimum at a certain depth that forms a sound channel for long-range underwater sound propagation. The geographic variation of sound channel is crucial in uses of underwater sound in various environments including ocean acoustic tomography and monitoring of global warming. In this work, sound speed and depth of the channel axis in the global ocean are characterized for their variation with the latitude, longitude, and depth.

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Zeros Of The Dedekind Zeta-Function, Mashael Alsharif Jan 2019

Zeros Of The Dedekind Zeta-Function, Mashael Alsharif

Electronic Theses and Dissertations

H. L. Montgomery proved a formula for sums over two sets of nontrivial zeros of the Riemann zeta-function. Assuming the Riemann Hypothesis, he used this formula and Fourier analysis to prove an estimate for the proportion of simple zeros of the Riemann zeta-function. We prove a generalization of his formula for the nontrivial zeros of the Dedekind zeta-function of a Galois number field, and use this formula and Fourier analysis to prove an estimate for the proportion of distinct zeros, assuming the Generalized Riemann Hypothesis.

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Quadratic Reciprocity: Proofs And Applications, Awatef Noweafa Almuteri Jan 2019

Quadratic Reciprocity: Proofs And Applications, Awatef Noweafa Almuteri

Electronic Theses and Dissertations

The law of quadratic reciprocity is an important result in number theory. The purpose of this thesis is to present several proofs as well as applications of the law of quadratic reciprocity. I will present three proofs of the quadratic reciprocity. We begin with a proof that depends on Gauss's lemma and Eisenstein's lemma. We then describe another proof due to Eisentein using the $n$th roots of unity. Then we provide a modern proof published in 1991 by Rousseau. In the second part of the thesis, we present two applications of quadratic reciprocity. These include special cases of Dirichlet's theorem …

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X-Ray Fluorescence Analysis Of Tuscaloosa Marine Shale Cuttings From Horizontally Drilled Wells, Xiaotian Wang Jan 2019

X-Ray Fluorescence Analysis Of Tuscaloosa Marine Shale Cuttings From Horizontally Drilled Wells, Xiaotian Wang

Electronic Theses and Dissertations

The Upper Cretaceous Tuscaloosa Marine Shale (TMS) is a gray to black fissile marine shale deposited at depth of between 10,000 and 20,000 ft near the ancient Gulf of Mexico. The TMS has been gradually developed as a hydrocarbon reservoir in the past several decades. But there are rare researches evaluating geochemical properties based on chemostratigraphy of the TMS. The objective of this research is to spatially evaluate geophysical properties and chemostratigraphy of the TMS, to characterize elemental changes along well paths and to evaluate the effect of basic sample clean on XRF results. The data available for this study …

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Bulky Thiolated Gold Nanomolecules: Synthesis, Characterization, Optical Properties, And Atomic Structure, Tanya Clorise Jones Jan 2019

Bulky Thiolated Gold Nanomolecules: Synthesis, Characterization, Optical Properties, And Atomic Structure, Tanya Clorise Jones

Electronic Theses and Dissertations

Gold nanomolecules (NMs) have a distinct number of gold atoms and thiolate ligands, Aux(SR)y, with unique spectroscopic, electrochemical, and chiral properties which are dependent on “x” and “y”. The properties of NMs are dictated by the type of capping ligand. The overall structure, size, surface percentage of ligands, and structure of an entire gold NM is changed based on the type of ligand used to synthesize it. Ligand type, such as aliphatic, aromatic or bulky play a crucial role in determining the size and composition of such NMs. A NM’s composition and properties vary widely depending on the type of …

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Building An Automated Q-A System Using Online Forums As Knowledge Bases, Kyle Moore Jan 2019

Building An Automated Q-A System Using Online Forums As Knowledge Bases, Kyle Moore

Electronic Theses and Dissertations

Question-Answer systems traditionally use expensive and difficult to produce structured knowledge bases. Recent systems have used unstructured natural language sources as their datasets, but most of those sources have been overly broad or difficult to extend. Online forums are a largely untapped source of information that can provide both depth and breadth when limited to a specific domain, as well as being adaptive to the introduction of new information. In this paper, I conjecture that online forums can be similarly and effectively used as an unstructured knowledge base for Question-Answer systems. I use a relatively simple summarization-based approach to analyze …

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The Effects Of Hypoxia And Freshwater Intrusion On The Eastern Oyster (Crassostrea Virginica), James Henry Gledhill Jan 2019

The Effects Of Hypoxia And Freshwater Intrusion On The Eastern Oyster (Crassostrea Virginica), James Henry Gledhill

Electronic Theses and Dissertations

Recent estimates revealed a significant decrease in oyster populations worldwide. This drastic decrease has detrimental effects on coastal and estuarine ecosystems. Two environmental stressors that are thought to be contributing to the oyster population decline are hypoxia and excess freshwater intrusion. In this study, effects of hypoxia and low salinity on oysters were investigated using a combination of laboratory and field-based methods. In the laboratory, oysters were exposed to 2, 4, or 8 days of hypoxia (< 2 mg/L dissolved oxygen) folloby 6 days of recovery in normoxic conditions. At the same time, caged oysters were exposed to a naturally occurring hypoxic event in the field. After 8 days, laboratory-exposed oysters shoevidence of immunosuppression indicated by significant downregulation of the immune-related gene thymosin-β4 (Tβ-4) and a significant decrease in total circulating hemocytes compared to controls. However, in field oysters exposed to a naturally occurring hypoxic event, no effect on total hemocyte counts and an upregulation of Tβ-4 was observed. In a second field study, to investigate how oysters respond to prolonged freshwater exposure, caged oysters were placed on 23 April 2019 at six reef sites in the Mississippi Sound along with in situ water quality sensors. One-hundred percent mortality of caged oysters occurred at four of the six sites. Of the 6 six sites, Henderson Point Reef and Kittiwake Reef shosome caged oyster survival. At Henderson Point, where higher mortality was observed compared to Kittiwake, a significant increase in lipid peroxidation was detected. Analysis of mRNA expression of surviving caged and native oysters revealed downregulation of genes involved in immune function, low oxygen response, and osmoregulation. These results show possible evidence of energetic depression which inhibits adequate adaptation to low salinity conditions. Energetic depression and increased oxidative damage could have contributed to higher oyster mortality. Dredge sampling of native oysters at the all Mississippi Sound field sites on 27 September 2019, following recovery to ~15 ppt salinity, still indicated 100% native oyster mortality due to the prior prolonged freshwater exposure. Continued monitoring of western Mississippi Sound oyster reefs is crucial to observe recovery of oyster populations.

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High Voltage Dye-Sensitized Solar Cells And Molecular Photocatalysis For Co2 Reduction, Roberta Ramalho Rodrigues Jan 2019

High Voltage Dye-Sensitized Solar Cells And Molecular Photocatalysis For Co2 Reduction, Roberta Ramalho Rodrigues

Electronic Theses and Dissertations

The development of high voltage solar cells is an attractive way to use sunlight to power electrocatalysts for water oxidation, electrocatalysts for CO2 reduction, and consumer electronics. Through careful molecular dye engineering and redox shuttle pairing, our group has reported a single-junction dye-sensitized solar cell (DSC) employing, for the first time, an iron redox mediator (Fe(bpy)33+/2+) in conjunction with a novel wide band gap dye (RR9). This system generates a high photovoltage of 1.42 V. To the best of our knowledge, this system is the highest photovoltage achieved by a single-junction DSC device without metal oxide doping. The RR9/Fe(bpy)33+/2+ redox …

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Manifoldlike Causal Sets, Miremad Aghili Jan 2019

Manifoldlike Causal Sets, Miremad Aghili

Electronic Theses and Dissertations

The content of this dissertation is written in a way to answer the important question of manifold likeness of causal sets. This problem has importance in the sense that in the continuum limit and in the case one finds a formalism for the sum over histories, the result requires to be embeddable in a manifold to be able to reproduce General Relativity. In what follows I will use the distribution of path length in a causal set to assign a measure for manifold likeness of causal sets to eliminate the dominance of nonmanifold like causal sets. The distribution of interval …

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X-Ray Crystal Structure Of Au36(Sph-Pch3)24 Nanomolecules, Vigneshraja Ganeshraj Jan 2019

X-Ray Crystal Structure Of Au36(Sph-Pch3)24 Nanomolecules, Vigneshraja Ganeshraj

Electronic Theses and Dissertations

Au36(SR)24 is one of the most comNanomolecules (NM) in gold NM field and crystal structures of Au36(SR)24 with different thiolate protecting ligand such as tert-butylbenzene thiol, thiophenol and cyclopentane thiol have been reported. It has been predicted that aromatic thiol protected Au36(SR)24 NM have same core structures like the other reported Au36(SR)24 NMs. Due to the steric and electronic conjugation effects the staples on the gold core exhibit minor changes in the bond length without affecting the gold core. By varying the Gold:Thiol ratio the NM size can be controlled. Herein, we report the synthesis, isolation and characterization of two …

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Interpreting Vegetation And Soil Anomalies In The Guarumen Area Of Northwestern Venezuela Using Remote Sensing Applications, Tyler Edward Ricketts Jan 2019

Interpreting Vegetation And Soil Anomalies In The Guarumen Area Of Northwestern Venezuela Using Remote Sensing Applications, Tyler Edward Ricketts

Electronic Theses and Dissertations

The Guarumen area of Venezuela is a tectonically active region that is approximately 1,640 mi2 across the northern portions of the Barinas Basin and the foothills of the Mérida Andes. It is structurally influenced by the Caribbean plate to the north, the Nazca plate to the west, and the Maracaibo block against the Guyana Shield of the South American Plate. These result in an oblique boundary that gives rise to the fold-and-thrust belt of the Mérida Andes to the west, and the Caribbean Mountain system to the north, in concordance to the right-lateral shearing that is evidenced by the Boconó …

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Use Of Seismic Refraction In Determining Rock Mass Anisotropy, Mohammad Najmush Sakib Oyan Jan 2019

Use Of Seismic Refraction In Determining Rock Mass Anisotropy, Mohammad Najmush Sakib Oyan

Electronic Theses and Dissertations

Seismic refraction is a popular method used by geological/geotechnical engineers to understand subsurface conditions. This method along with information collected from borings produce a realistic image of the ground beneath us. The goal of this study is to define and test a set of procedures to use seismic refraction alone to create high quality images of subsurface conditions. The focus is on areas with several meters of soil overlain by bedrock. The application of these procedures will minimize construction costs by eliminating the need for multiple boreholes. The results show that two important criteria must be met for successful application …

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Organic Sensitizers For High Efficiency Dye-Sensitized Solar Cells, Adithya Peddapuram Jan 2019

Organic Sensitizers For High Efficiency Dye-Sensitized Solar Cells, Adithya Peddapuram

Electronic Theses and Dissertations

After the industrial revolution in 19th-century energy, demand has increased exponentially. Relying on fossil fuels long term is not a good option due to their non-renewable nature and concerns about burning fossil fuels raising carbon dioxide levels in atmosphere. This dissertation describes, utilizing sunlight for electricity production with dye-sensitized solar cells (DSCs). DSCs are an attractive solar technology due to processing advantages over traditional solar cells. To improve the stability of DSCs, strong surface binding dyes are important. This work studies the dual anchor dual donor (DD-π-AA) dye framework with various donors (electron rich π-systems) and π-bridges (electron neutral π-systems). …

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Near-Infrared High Efficiency Organic Dye Sensitized Solar Cells (Dscs) And Biological Fluorescent Imaging Dyes, Yanbing Zhang Jan 2019

Near-Infrared High Efficiency Organic Dye Sensitized Solar Cells (Dscs) And Biological Fluorescent Imaging Dyes, Yanbing Zhang

Electronic Theses and Dissertations

With the energy consumption increase every year, the non-renewable energy sources such as fossil fuels, natural gas, and coal will not sustain forever. In this case, searching for a way to develop a renewable energy source is an emergency. For decades, dye-sensitized solar cells (DSCs) have received intensive attention due to their high power conversion efficiency and low material cost. This dissertation describes efforts to design and synthesize near-infrared organic dyes to apply to two systems: first, for use in the improvement of DSCs by the optimization of electron rich components such as ullazine and cross-conjugated -bridges to increase photon-to-electricity …

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Acoustic Radiation Force On A Fluid To Fluid Boundary By Phase Plate Focused Ultrasound, Robert Lee Lirette Jan 2019

Acoustic Radiation Force On A Fluid To Fluid Boundary By Phase Plate Focused Ultrasound, Robert Lee Lirette

Electronic Theses and Dissertations

In this study, the physics and applications of the ultrasonic radiation force at the interface between two immiscible fluids were investigated. These studies were performed using low-profile discrete-stepped lenses to the modify the phase of the incident radiation generating multiple field morphologies. In its first application to acoustics, a fraxicon lens was developed to approximate the field generated by an axicon. This type of lens creates a minimally diffractive Bessel beam and long depth of focus that is useful in ultrasonic imaging, therapy, and non-destructive evaluation techniques. Fields modified by fraxicon, Fresnel, and axicon lenses were characterized experimentally by scanning …

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Generalized Radial Transport Model For Interpreting Convergent Flow Tracer Tests In Fractured Rock, Md Lal Mamud Jan 2019

Generalized Radial Transport Model For Interpreting Convergent Flow Tracer Tests In Fractured Rock, Md Lal Mamud

Electronic Theses and Dissertations

The double-porosity Generalized Radial Transport (GRT) model is an extension of the generalized radial flow approach developed for hydraulic test interpretation. In both approaches, a flow dimension characterizes the change in flow area versus radial distance from the borehole. The GRT model collapses to a 1D, radial, and spherical advection dispersion equation (ADE) for integer flow dimensions of 1, 2, and 3, respectively. And, the model also transforms to sub-linear, sub-radial, sub-spherical and eventually transform to super-spherical transport model for non-integer flow dimension, n of 0 < n < 1, 1 < n < 2, 2 < n < 3 and n >3 respectively. Non-integer flow dimensions, especially sub-radial, are commonly reported from pumping tests in …

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Development Of Cobalt And Iron Catalysts Bearing Rigid Polydentate Ligands For Proton Reduction And C-H Bond Oxidation, Lizhu Chen Jan 2019

Development Of Cobalt And Iron Catalysts Bearing Rigid Polydentate Ligands For Proton Reduction And C-H Bond Oxidation, Lizhu Chen

Electronic Theses and Dissertations

The demand for energy consumption has increased exponentially since the Industrial Revolution. The major source of this energy has been and continues to be fossil fuels. The depletion of fossil fuels and environmental concerns associated with their combustion has motivated us to develop a renewable energy alternative to meet future energy demands. Hydrogen is a clean energy alternative to fossil fuels, which can be generated from solar-driven water splitting. However, more efficient and inexpensive catalysts for the hydrogen evolution reaction (HER) are needed. In this context, hydrogen production has been investigated with a stable and highly reactive cobalt-based catalyst. While …

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Electrochemical Studies Involving Co2 Reduction With Rhenium-Based Catalysts And For Guanosine Monophosphate Oxidation, Kayla A. Milano Jan 2019

Electrochemical Studies Involving Co2 Reduction With Rhenium-Based Catalysts And For Guanosine Monophosphate Oxidation, Kayla A. Milano

Electronic Theses and Dissertations

The following chapter of this thesis will cover the oxidation of guanine monophosphate (GMP). GMP has been linked to numerous conditions when it is oxidized or damaged. There have been two oxidation pathways suggested in association to the oxidation of GMP: EPT and MS-EPT. The ideal conditions for GMP’s oxidation is still be studied and collected. The study focuses on the acetate versus phosphate buffer, varying base concentration in phosphate buffer, and the varying concentration of ruthenium complex, a redox mediator.

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Investigation Of Narrow Bipolar Events In Mississippi Thunderstorms, Sampath Asiri Bandara Jan 2019

Investigation Of Narrow Bipolar Events In Mississippi Thunderstorms, Sampath Asiri Bandara

Electronic Theses and Dissertations

In the first part of the study FA and Log-RF data were used to examine low-altitude (<8.0 km) negative NBEs (NNBEs) to see how many -CG flashes were initiated by NNBEs. Out of 686 -CG flashes only 33 (5%) flashes were initiated by an NNBE. These NNBEs occurred at an average altitude of 6.2 km had average amplitude (range-normalized amplitude to 100 km) of 0.4 V/m and had average VHF (Log-RF) power of 130 W. Since the low-altitude NNBEs were substantially weaker than positive NBEs that initiate intracloud (IC) flashes it is hypothesized that -CG flashes are easier to initiate than IC flashes. The second part of the study investigated the properties of 201 positive NBEs (+NBEs). The +NBEs were classified in two ways: into Types A-D [Karunarathne et al. 2015] and into three different groups: Isolated Not-isolated and IC flash-initiator or INBE [Wu et al. 2014]. The average VHF (Log-RF) power of NBEs within the A-D categories were 1.9 4 9.8 and 13.2 kW respectively while the powers for the Isolated Not-isolated and INBE categories were 10.1 4 and 10.1 kW respectively. The third study considered 34 NBEs that occurred close in space and time to each other: 13 pairs of NBEs one group of three +NBEs and one group of five +NBEs. The NBEs were overlaid on radar data of the parent thunderstorms. The data indicate that the individual NBEs in each group initiated in separate intense electric field regions of small extent rather than in a single large-scale electric field region. This dissertation investigates Narrow Bipolar Events (NBEs) which are a type of short-duration (10- 30 µs) lightning discharge. The study primarily used data from NBEs collected in 2016 at seven sensor sites within 50 km of Oxford Mississippi USA. Each sensor site had three electromagnetic antennas called Fast Antenna (FA) dE⁄dt and Log-RF with bandwidths of 0-2.5 MHz 0-1.0 MHz and 186-192 MHz respectively. NBEs are often isolated from other lightning events in thunderclouds but they sometimes initiate negative cloud-to-ground (-CG) and intracloud (IC) lightning flashes or they can occur during these flashes.

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Application And Refinement Of Molecular Ecology Techniques For Amphibian Conservation, Stephanie Marie Burgess Jan 2019

Application And Refinement Of Molecular Ecology Techniques For Amphibian Conservation, Stephanie Marie Burgess

Electronic Theses and Dissertations

Wildlife conservation has become increasingly difficult due to habitat loss habitat fragmentation and land use change. Thus conservationists have embraced advances in molecular ecology such as landscape genetics and microbial bioinformatics that employ genetic techniques to further understand the relationship between individuals and their environment. In landscape genetics model inferences can be used to identify features that facilitate or resist gene flow providing a framework for anticipating the impacts of land use changes on a species’ ability to disperse. However the factors that affect the transferability of landscape genetics inferences are poorly understood and little is known about the effect …

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Theranostics Based On Linear Dendritic Block Copolymers, Jon Williams Jan 2019

Theranostics Based On Linear Dendritic Block Copolymers, Jon Williams

Electronic Theses and Dissertations

When combining imaging and therapeutic motifs, known as theranostics, amphiphilic diblock copolymers have a strong precedent of success. These polymers can self-assemble into a variety of morphologies that are known to concentrate in areas of inflammation such as tumors. However, prediction of size and morphology from polymer structure still remains an open challenge. Another system with promise of therapeutic efficacy are tree-like struc- tures known as dendrimers, such as poly(amidoamine) (PAMAM) and bis-(hydroxymethyl) propionic acid (bMPA), which can uptake drugs and dyes into their branches. It is desireable to combine these two motifs, using linear-dendritic block copolymers (LDBCs). These represent …

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Towards Misleading Connection Mining, Md Main Uddin Rony Jan 2019

Towards Misleading Connection Mining, Md Main Uddin Rony

Electronic Theses and Dissertations

This study introduces a new Natural Language Generation (NLG) task – Unit Claim Identification. The task aims to extract every piece of verifiable information from a headline. The Unit Claim identification has applications in other domains; such as fact-checking where the identification of each verifiable information from a check-worthy statement can lead to an effective fact-check. Moreover, the extracting of the unit claims from headlines can identify a misleading news article, by mapping evidence from contents. For addressing the unit claim identification problem, we outlined a set of guidelines for data annotation, arranged in-house training for the annotators and obtained …

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Optimizing The Performance Of Complex Engineering Systems Aided By Artificial Neural Networks, Khalil Qatu Jan 2019

Optimizing The Performance Of Complex Engineering Systems Aided By Artificial Neural Networks, Khalil Qatu

Electronic Theses and Dissertations

In the first problem Polyetherimide graphene nanoplatelets papers (PEIGNP) were tested with different graphene loadings varying from 0-97 weight percent (WT%). The resulting stress-strain curves were utilized to develop two ANN models. Stress-controlled and strain-controlled models. Both models shoan excellent correlation to the experimental. Several Mechanical properties were calculated from the predicted stress-strain curves namely; toughness maximum strength maximum strain and maximum tangent modulus. Both models captured the same overall behavior of the PEIGNP composite. However the strain-controlled model was found to predict lower stress than the stress-controlled model. Finally a Graphical User Interface (GUI) was developed to aid in …

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Ni And Au Transition Metal Complexes In The Photocatalytic Co2 Reduction Reaction, Shakeyia Davis Jan 2019

Ni And Au Transition Metal Complexes In The Photocatalytic Co2 Reduction Reaction, Shakeyia Davis

Electronic Theses and Dissertations

The production of renewable fuels by the conversion of solar energy into chemical energy is a challenge. Photocatalytic and electrocatalytic conversion of CO2 to usable fuel precursors are approaches to overcoming this challenge. The two-electron reduction of carbon dioxide to carbon monoxide is an appealing process because CO can be used as a commodity chemical in industrial processes. Many molecular CO2 reduction catalysts have been reported and commonly use expensive late transition metals. These systems are inspired by natural photosynthesis and generally combine a photosensitizer, a catalyst, and a sacrificial electron donor. This work focuses nickel and gold complexes as …

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Utilizing Various Neural Network Architectures To Play A Game Developed For Human Players, Michael Blake Arender Jan 2019

Utilizing Various Neural Network Architectures To Play A Game Developed For Human Players, Michael Blake Arender

Electronic Theses and Dissertations

Neural Networks have received an explosive amount of attention and interest in recent years. Despite the fact that Neural Network algorithms having existed for many decades, it was not until recent advances in computer hardware that they saw widespread use. This is in no small part due to the success these algorithms have had in tasks ranging from image classification, voice recognition, game theory, and many other applications. Thanks to recent strides in hardware development, most importantly in the advancements in Graphics Processor Units including the capabilities of modern GPU Computing, Neural Networks are now capable of solving tasks at …

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