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Full-Text Articles in Physical Sciences and Mathematics
The Facile Preparation Of Bis(Imino)Pyridine Complexes Via Mechanochemistry And Inorganic Synthons Via Benign Reductants, Thomas Shaw
Electronic Theses and Dissertations, 2020-2023
This thesis is comprised of two key themes: (i) leveraging mechanochemical synthetic methods for the green preparation of bis(imino)pyridine ligands and associated first row transition metal coordination complexes, and (ii) the preparation and characterization of both historic and novel mid-valent inorganic synthons via the use of dimethylphenylsilane as a stoichiometric reducing agent. The first portion of this thesis highlights the utilization of solvent-free vibratory ball-milling in lieu of traditional, solvent-based refluxes. A variety of both bis(imino)pyridine ligands and complexes were formed in drastically reduced timeframes with solvent-economical work-up procedures. This methodology was also leveraged for the isolation of acetyl(imino)pyridine ligands …
Tuning The Fluid Wetting Dynamics On Gold Microstructures And Conductivity Of Polyaniline Using Photoactive Compounds, Ali Haghighat Mesbahi
Tuning The Fluid Wetting Dynamics On Gold Microstructures And Conductivity Of Polyaniline Using Photoactive Compounds, Ali Haghighat Mesbahi
Electronic Theses and Dissertations, 2020-2023
Organic photochromic compounds (OPCs) are considered as a class of light sensitive compounds that undergo reversible structural transformation of their physicochemical properties (i.e., polarity and charge distribution) upon light irradiation as an external stimulus. These compounds have been extensively studied for decades, and are used in various applications such as biomedicine, chemical sensors and harvesting solar energy. In this thesis, applications of OPCs were investigated under two different projects: 1) controlling wettability of flat and microstructured gold surfaces and 2) controlling the electrical conductivity of polyaniline. The first project demonstrates how photoactive compounds can be used to tune the surface …
Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar
Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar
Honors Undergraduate Theses
Hybridization of two or more DNA or RNA strands is well documented for the process taking place with all strands free in solution or when one strand is immobilized on a substrate. This study contributes to the investigation of the hybridization process when two single DNA strands (ssDNA) are in close proximity. We took advantage of an X sensor in which hybridization of four DNA strands enables the formation of a DNA four-way junction (crossover or X) structure. We immobilized multiple layers of crossover structures to study its hybridization being triggered by short ssDNA coming from solution and further investigate …
Analysis And Characterization Of Smokeless Powders And Smokeless Powder Residues, Emily Lennert
Analysis And Characterization Of Smokeless Powders And Smokeless Powder Residues, Emily Lennert
Electronic Theses and Dissertations, 2020-2023
The ability to associate a smokeless powder, smokeless powder residue, or organic gunshot residue (OGSR) to one another may be helpful in determining the origin of a suspected sample and aid in linking a suspect to a crime scene. In this study, smokeless powders were extracted and analyzed via gas chromatography – mass spectrometry (GC-MS) and direct analysis in real time – high resolution mass spectrometry (DART-HRMS). Subsequently, group definition was performed using hierarchical cluster analysis and principal component analysis followed by internally validated classification models. Then, smokeless powder residues were generated in-lab and extracted. Resulting residue data from each …
Polymer Derived Ceramic For Lithium-Ion Storage, And Electrospun Polyelectrolyte Fiber For Heavy Metal Ions Removal, Zeyang Zhang
Polymer Derived Ceramic For Lithium-Ion Storage, And Electrospun Polyelectrolyte Fiber For Heavy Metal Ions Removal, Zeyang Zhang
Electronic Theses and Dissertations, 2020-2023
This dissertation includes two major projects. The first project investigated the great potential of polymer-derived ceramics (PDCs) as lithium-ion battery anode materials with good cycling stability and large capacity. SiCNO ceramic nanoparticles were produced by pyrolysis of polysilazane nanoparticles synthesized via an oil-in-oil emulsion crosslinking. The SiCNO nanoparticles had an average particle size of around 9 nm and contained graphitic carbon, Si3N4, and SiO2 domains. The electrochemical behavior of SiCNO nanoparticles anode was investigated to evaluate the Li-ion storage performance and understand its mechanism of Li-ion storage. The lithiation of SiCNO was observed at ~0.385 V versus Li/Li+. The anode …
Reticular Design And Synthesis Of Metal-Organic Frameworks With Targeted Emergent Properties, David Fairchild
Reticular Design And Synthesis Of Metal-Organic Frameworks With Targeted Emergent Properties, David Fairchild
Electronic Theses and Dissertations, 2020-2023
The research presented in this dissertation describes the design and synthesis of substitutional-solid-solution-based multivariate metal-organic frameworks (SSS-based MTV MOFs) with functionalized organic linkers to study their emergent properties in the crystalline solid state. The synthetic versatility and tunability of organic chemistry coupled with the predictable organization of inorganic structures enables MTV MOF systems to further the fundamental understanding of structure-composition-property relationships for the targeted design of applied materials due to their ability to control the structure, composition, and property independently. To begin, a set of terphenyl linkers with varied steric and electronic properties were crystallized as a family of UiO-type …
Development Of A Computational Application To Aid With Chemometric And Forensic Analysis Of Fire Debris Samples, Michelle Corbally
Development Of A Computational Application To Aid With Chemometric And Forensic Analysis Of Fire Debris Samples, Michelle Corbally
Electronic Theses and Dissertations, 2020-2023
Fire debris analysis is a forensic science discipline that determines if an ignitable liquid residue is present or absent in a fire debris sample. Currently, fire debris analysis results in categorical statements based on qualitative data, not the quantitative evidentiary value of data. The purpose of this research was to develop a novel software application to aid fire debris analysts in the identification and classification of ignitable liquid residues that are found in fire debris samples. The developed application uses target factor analysis (TFA) and Pearson correlation for compound identification in gas chromatograms using mass spectral comparison and allows for …
Development Of An Hipsc-Cortical Neuron Long-Term Potentiation Model And Its Application To Alzheimer's Disease Modeling And Drug Evaluation, Kaveena Autar
Electronic Theses and Dissertations, 2020-2023
Alzheimer's disease (AD) is commonly characterized by a loss of cognitive function due to the deterioration of neuronal synapses from the presence of senile amyloid beta-42 (Aß42) plaques. Evaluating cognitive deficits caused by Aß42 using human cortical neurons poses a challenge due to sourcing difficulties, and the use of animal models to assess drug efficacy creates biological hurdles from lack of species translatability. Recent advances in induced-pluripotent stem cell technology have enabled the development of mature, human-based cortical neuron models. The development of an hiPSC-cortical neuron differentiation protocol facilitates the exploration of disease onset and functional analysis from a patient-derived …
Surface Engineering For Controlled Growth And Deposition Of Nanomaterials - Assembly And Design At The Nano-Microscale, David Fox
Electronic Theses and Dissertations, 2020-2023
Materials with nanoscale dimensions offer several important benefits over bulk materials (e.g. increased surface area, low-cost, deviation from bulk properties, etc.). Such materials are critical components for next-generation energy storage materials, optoelectronic devices, and catalyst systems. However, these materials are often processed in liquid media, and their diminutive structures are fragile in the presence of capillary forces. As such, preparing uniform and stable nanomaterial coatings is a significant challenge. Herein, we discuss an approach where the substrate itself is factored into the assembly and growth of these materials. First, nanoporous surfaces were utilized to achieve a uniform deposition of one-dimensional …
Genomic Analysis Of Pollen Grains For Forensic Applications, Luz Kelley
Genomic Analysis Of Pollen Grains For Forensic Applications, Luz Kelley
Electronic Theses and Dissertations, 2020-2023
With over 300,000 plant species on the planet and more than 90% of them relying on pollen for reproduction, palynology, the study of pollen grains plays a vital role in many research fields. One of them is forensic palynology, which uses pollen as a proxy to link individuals or objects to a location or instance. It relies on the fact that (1) pollen is an ever-present feature of the environment; (2) different locations have different pollen signatures, allowing for inference related to spatial tracking; (3) plants bloom at different times, allowing for temporal inference; and (4) pollen is exceptionally durable …
Investigation Of Catalysis Of Nitration By Cytochrome P450s, Lannika Johnson
Investigation Of Catalysis Of Nitration By Cytochrome P450s, Lannika Johnson
Honors Undergraduate Theses
TxtE is a protein related to cytochrome P450 enzymes, which catalyze a number of reactions that typically involve oxygen and not nitrogen. It has been discovered that TxtE can nitrate tryptophan through an unusual reaction in which it uses nitric oxide (NO) as a nitrogen donor to install the nitro group despite NO typically being considered toxic to bacteria. This project will determine if all cytochromes P450 can catalyze nitration as long as they are given NO. This will have an impact on understanding drug delivery and metabolism for which nitration is important.
Synthesis And Characterization Of Silver-Gold Nanocage With Enhanced Thermal Stability, Victoria Ten
Synthesis And Characterization Of Silver-Gold Nanocage With Enhanced Thermal Stability, Victoria Ten
Honors Undergraduate Theses
Silver-gold nanocages have attracted considerable research interest recently due to their excellent performance in the fields of biomedicine and photocatalysis. These applications oftentimes manipulate at elevated temperatures and therefore impose demands on the thermal stability of the cage structures. To better understand this subject, in this work, we systematically evaluated the thermal stability of two nanocages with different wall thicknesses of 3.8 nm and 13 nm, both in the solution-phase (diethylene glycol) and solid-phase (in-situ STEM). The results revealed that the nanocages with thicker walls exhibited better thermal stabilities in both phases. By monitoring and analyzing the morphology changes of …
Heterogenous Reduction Of Co2 Over Boron-Rich Alb2, Jose C. Berger
Heterogenous Reduction Of Co2 Over Boron-Rich Alb2, Jose C. Berger
Honors Undergraduate Theses
Evidence suggests that the recent drastic changes in the global climate have been caused by greenhouse gases, especially CO2. As a result, scientists are aiming to develop processes that either minimize the production of these gases or convert them into products of higher value. To that end, the catalytic properties of a two-dimensional boron-rich material were investigated. Herein is reported that such a material can reduce CO2 into benzene, C3 species, and C4 species at relatively low temperatures (225-450 ℃) and pressures (0.38 MPa). Current data suggest that a low-temperature induction period (e.g., 225 ℃) …
Photocatalytic Hydrogen Production Over Boron Rich Solids, Emma E. Blanco
Photocatalytic Hydrogen Production Over Boron Rich Solids, Emma E. Blanco
Honors Undergraduate Theses
The greenhouse emission produced from the combustion of fossil fuels, such as methane (CH4) and carbon dioxide (CO2), are linked to global warming crisis because of their ability to absorb heat emitted to space by the Earth’s atmosphere. Over the last century, methane is estimated to have the Global Warming Potential (GWP) estimated to be 28-36 times larger than carbon dioxide. Although it is released in smaller quantities, methane traps nearly 90 times more heat than CO2. While recent research efforts has focused on the capture and conversion of CO2, these efforts …