Physical Sciences and Mathematics Commons^™

Development And Novel Applications Of Halogenating Agents., Sagar Ravso Mudshinge

Electronic Theses and Dissertations

Organic halides are extensively utilized as synthetic intermediates in areas such as pharmaceuticals, agrochemicals, and material polymers. While many halogenating agents have been developed, they continue to have low efficiency or selectivity, are difficult to handle, and often have limited substrate scope. To address this issue, our laboratory has developed novel halogenating agents with improved stability and efficiency. In these studies, we demonstrated a novel application of halogenating reagent, HCl·DMPU, in the nitrile synthesis. We developed a novel method for C−SCF₃/SeCF₃ cross-coupling reactions using gold redox catalysis. We developed a novel trifluoromethylating agent in a cost-effective and …

Guest Host Chemistry Part I: The Synthesis Of Metal Selective Sensors Part Ii: The Synthesis Of Antibiotic Precursors And Intermediates, Trevor Moss Hagemann

Theses and Dissertations

Part 1: Metal Selective Sensors

The work herein describes the creation of a library of sensors for the detection of metal ions in aqueous systems. The solid support these dyes are attached to facilitates a continuous measurement of metal ion concentrations in aqueous systems. The sensors are based on an azo dye core structure wherein detection of metal ions is observed by the change in absorbance of the dye upon binding. These sensors are capable of detecting metal ions in the ppb range, specific dyes interacting with specific metal ions cause distinct spectral changes, providing substantial information. the aggregate response …

Design And Synthesis Of Chiral And Achiral Benzodiazepines And Imidazodiazepines As Α–Subtype Selective Gabaar Positive Modulators To Treat Schistosomiasis, Epilepsy, Asthma And Some Mental Disorders, Md Yeunus Mian

Theses and Dissertations

Part I: Design, synthesis, and biological evaluation of non-sedating anti-schistosomal agents

Schistosomiasis is a parasitic flatworm infection with only one drug therapy currently on the market, praziquantel. An old lead identified by Roche, meclonazepam (US Patent 4031078A) displayed antiparasitic efficacy but was not pursued due to dose-limiting sedation in human clinical trials (S. Afr. Med J. 1979 Apr 14;55(16):617-8, PMID: 380021). However, given the superior spectrum of activity meclonazepam displays relative to praziquantel (which is unable to cure immature parasites within the host) and advances in the understanding of benzodiazepine SAR at human GABAARs, the study of this benzodiazepine was …

Understanding The Transition From General To Organic Chemistry, Hannah Chan

Student Scholar Symposium Abstracts and Posters

Organic chemistry is commonly known to have high failure rates and regarded as one of the most difficult courses offered in undergrad. This study assessed whether a modified general chemistry curriculum allowing for more time focused on foundational organic chemistry concepts in general chemistry can improve students’ grade outcome and/or self efficacy when transitioning from general to organic chemistry courses. Two separate variables were tested: grade outcome and self efficacy. Using an independent sample t-test, a comparison of the two groups (modified versus traditional general chemistry) was performed. Grades were assessed by giving students four questions (out of 4 points …

Understanding Biogeochemical And Physical Controls On Methane Air-Sea Exchange Fluxes In The Pacific Ocean, Sarah Raney

Master's Theses

Methane and trace element samples were collected on GEOTRACES GP15 Pacific Meridional Transect (PMT) cruise conducted between the Aleutian Islands (57 °N) and Tahiti (20 °S) from September to November 2018. Uncertainty in methane air-sea exchange fluxes was determined using a propagation of errors approach. Fluxes ranged from -0.88 to 4.9 µmol CH₄ m^-2 d^-1. Average CH₄ flux along the Alaskan margin was 2.2 ± 2.9 µmol CH₄ m^-2 d^-1. Methane fluxes decreased moving southward and increased to their open ocean maximum around 20 °N before declining in equatorial waters. Near …

The Dissolution And Recovery Of Critical Materials (Li2co3 And Uf6) From Ionic Liquid, Cassara Higgins

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lithium and uranium are critical materials in both the energy industry and for national security. Lithium is necessary for the next generation of batteries and 6Li is valuable for the production of tritium necessary for both fusion energy and to maintain our nuclear stockpiles. Uranium is a fuel source or precursor fuel source for commercially operating nuclear fission power. The monitoring of uranium hexafluoride (UF6) enrichment at foreign facilities is important for the monitoring of nuclear safeguards and enforcement of non-proliferation treaties. Recovery methods for lithium at the end of life of batteries are necessary to ensure abundance of the …

Revisiting The Chemistry Of Uranium And Rhenium Fluorides: Implication To Fuel Cycle And Nuclear Forensics Science, James Amos-Aimé Louis-Jean

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fluorine plays a major role in the nuclear industry where F2(g) and HF(g) are critical to the preparation of UF6 and UF4. These materials are prepared for uranium enrichment to increase the isotopic concentration of 235U. During separation efforts, the isotope 99Tc (a high yield fission product, 6.1% from 235U) is extracted along with uranium and can be converted to binary technetium fluorides (i.e., TcF4, TcF6) during re-enrichment of used uranium material. This provides a route for 99Tc to reenter the reactor environment and affect the nuclear properties of fuel pellets made with reprocessed uranium. The objective of this work …

Differential Protein Expression In Bacteriophages Crimd And Larva, Daria Moody

Undergraduate Honors Theses

Proteomics studies allow us to answer questions about differential protein expression across different systems. Mass spectrometry is a powerful tool in these studies due to the distinct masses of the amino acids that compose proteins. In our experiment, we used a bottom-up approach and focused on two bacteriophages found on the William & Mary campus, CrimD and Larva. The infection of Mycobacterium smegmatis, a nonpathogenic model for tuberculosis, by these two bacteriophages was frozen at five different timepoints, and our goal was to compare the differential protein expression across the samples in order to gain a greater understanding of …

The Effects Of An R103q Mutation On The Chemical And Physical Properties Of The Enzyme Cytochrome C Nitrite Reductase (Ccnir), Shahama Alam

Theses and Dissertations

Cytochrome c Nitrite Reductase (ccNiR) is a periplasmic homodimeric decaheme enzyme that catalyzes the reduction of nitrite to ammonium in a process that involves six electrons and eight protons. The project described herein explored the properties of the Shewanella oneidensis R103Q ccNiR variant and compared them to the properties of the wild type enzyme. Under standard assay conditions, which use the strong reducing agent methyl viologen monocation radical (MVred) as an electron source, the R103Q variant still catalyzes reduction of nitrite to ammonium, albeit with an MVred turnover rate that is 20% of the wild type’s (780 ± 50 s-1 …

The Activity Of Qh Ii 66 And It’S Analogs In Medulloblastoma, Melanoma And Non-Small Cell Lung Cancer Cell Lines., Taukir Ahmed

Theses and Dissertations

GABAARs (gamma-aminobutyric acid type A receptors) are transmembrane pentameric ligand-gated chloride ion channels that respond to GABA, the central nervous system's principal inhibitory neurotransmitter (CNS). The benzodiazepines (BZDs) bind between the GABAAR α+γ2-subunits at their extracellular interface. The binding of ligands to distinct subunits of GABAA receptors, notably the α1-6β2/3γ2 ion channels, can have a wide range of effects on brain activities. The sedative, ataxic, amnesic, anticonvulsant, and addictive actions of GABAARs' α1-subtype selective ion channels should be avoided, except for the anticonvulsant and anxiolytic effects, while creating ligands for this BZ allosteric modulatory site. Many studies have linked the …

In Vitro And In Vivo Identification And Quantification Of Carmofur And 5-Fluorouracil Using Tandem Mass Spectrometry, Mohammad Mohiminul Islam

Theses and Dissertations

Glioblastoma is the most aggressive solid tumor of the brain. Prior studies from our lab found that carmofur, also known as 1-hexylcarbanoyl 5-fluorouracil (HCFU) is a promising candidate in suppressing and killing tumor cell lines compared to the FDA-approved drug temozolomide. Originally developed as pro-drug of 5-fluorouracil (5-FU), carmofur has been in use in clinic for the treatment of colorectal cancer for over four decades in Japan. Having it used in clinics, it has a high probability of repurposing for diseases with no cure such as glioblastoma. Carmofur has also been found effective against other cancers such as head and …

Stability, Electronic Structure, And Nonlinear Optical Properties In Clusters And Materials: A Synergistic Experimental-Computational Analysis, Maksim Kulichenko

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The main objective of Chemistry as a science is an understanding of how and why certain atoms are bonded together and what effects these bonds cause. Modern computational chemistry offers a wide range of tools that greatly assist the exploration of vast chemical space replacing expensive trial-and-error experimental approaches. Computational chemistry may serve to characterize newly synthesized compounds and provide atomic scale insights inaccessible to experimentalists’ vision. Moreover, predictive power of computational chemistry may be used as a guidance for future experiments and for the rational design of new compounds with desired properties.

This dissertation demonstrates the capabilities of joint …

Part I: Synthesis Of Quinolones For Inhibition Of The Β-Barrel Assembly Machine In Gram Negative Bacteria; Part Ii: Synthesis Of Azo Dye Sensors For Detection Of Metal Ions In Aqueous Environments, Katryna Williams

Theses and Dissertations

Part I: Antibiotic resistance in Gram-negative bacteria is a growing cause of concern worldwide. Thousands of people die from antibiotic resistant bacteria every year. The β-Barrel Assembly Machine (BAM) in Gram-negative bacteria plays a role in antibiotic resistance as its porin, BamA, can regulate which molecules enter the cell, meaning it can prevent antibiotics from entering the bacterial cell. BamA exists in an open and closed form and is only selective in its closed form. BamA opens and closes through the H-bonding of two intramolecular β-strands. It is theorized that the creation of a β-sheet mimetic, based on work done …

Design And Synthesis Of Thiazole-Based Small Molecules To Inhibit The Inflammatory Cytokine Oncostatin M, Samuel Randall

Boise State University Theses and Dissertations

The body’s innate ability to produce an inflammatory response due to tissue irritation or damage is essential for growth and survival. The inflammatory response can be triggered by numerous stimuli, including physical trauma, inhalation of dangerous debris (such as silica and asbestos), tobacco/alcohol consumption, microbiota, diet, and other lifestyle stressors. In a well-orchestrated inflammatory response, the circulatory system increases blood flow and capillary permeability in the inflamed area to deliver nutrients, white blood cells, and inflammatory mediating molecules. However, a dysregulated inflammatory response can lead to chronic inflammation. Emerging evidence continues to frame oncostatin M (OSM) as a pro-inflammatory cytokine …

Solvent Effects In Phenol Hydrogenation On A Supported Ruthenium Catalyst, Daniel Mckeon

Honors College

Growing concerns around climate have piqued interest in using biobased alternatives in place of fuels and chemicals traditionally made from petroleum. Lignocellulosic biomass has been noted for its potential as a biobased chemical precursor in the context of a biorefinery. It can be pyrolyzed to yield an oil, but catalytic upgrading is required to lower oxygen content to suitable levels. Ruthenium supported on titania has been identified as a catalyst suitable for hydrodeoxygenation of oxygenated aromatic pyrolysis products in the liquid phase. In liquid phase reactions, intermolecular attractions between the solvent and the reactants can significantly change chemical activities and …

Compatible Blends Of N-Type Polymer Semiconductors: Impact On The Morphology And Mechanics Of Flexible Optoelectronics, Zachary C. Ahmad

Honors Theses

Conjugated polymers offer the potential for the development of robust, low-cost electronics, but achieving high mechanical deformability and high charge transport simultaneously in polymer semiconductors remains a significant challenge. In this work, blends of conjugated polymers were investigated to elucidate the influence of compatible conjugated blends on polymer morphology, mechanics, and electrical properties (using a partially conjugated polymer as the soft matrix and a fully conjugated polymer as the electrically active component). This work achieves a fundamental understanding of blend morphology for these similar components by establishing the framework for how they deform with strain. Grazing-incidence wide-angle X-ray scattering (GIWAXS) …

Development Of Stimuli-Responsive Liposomes For Drug Delivery Applications, Jinchao Lou

Doctoral Dissertations

Liposomes are spherical nano-assemblies that are proven to be effective drug delivery vehicles. Due to their unique bilayer structures, they are able to encapsulate both hydrophilic and hydrophobic drugs in their aqueous inner core and membrane bilayers, respectively. While liposomal delivery platforms exbibit numerous advantages, the therapeutic efficacy of these platforms would be enhanced by developing triggered release strategies such that one can tune the timing and location of the cargo release in a controlled manner. In this dissertation, we mainly present the development of stimuli-responsive liposomes targeting different disease-associated metabolites utilizing rationally designed synthetic lipid switches.

In Chapter 2, …

A Performance Evaluation Of Architectural Coatings To Preserve Aerosol Paint On Concrete, Riley Morris

All Theses

The growing movement of assigning cultural and heritage value to graffiti and street art is one without a preservation solution to ensure the longevity of these works in-situ in an outdoor environment. The goal of this thesis was to provide a comprehensive evaluation of six architectural topcoats’ performance when applied as a conservation treatment to outdoor aerosol graffiti and street art on concrete substrate. An artist’s quality, durable, color-fast spray-paint was applied to twenty-eight concrete test panels to mimic the application of graffiti or street art. Six topcoats, Prosoco SC-1, Prosoco Gloss n’ Guard WB, Keim Faceal Oleo HD®, Keim …

Control Of Irradiation Wavelength And Quantum Yield Of Photocleavable Cages, Jingxuan Ma

Theses and Dissertations

An important component of biological research is the precise regulation of biomolecules in their physiological environment. Recent advances in neuroscience, have made it possible to regulate the activity of neurotransmitters using photocleavable protecting groups (PPGs), which are also known as cages. This enables the use of light as a trigger to activate selected neurons via photo release of agonists with precise control of timing as well as synaptic site, popularly referred to as spatiotemporal control. In recent years, a variety of PPGs have been developed and applied to biomolecular cages. PPGs can be classified according to their absorption wavelengths (from …

Development Of Diagnostic Tools And Analysis Of The Density Functional Theory Zoo, Pierpaolo Morgante

Theses and Dissertations

The main goal of this dissertation is to give an overview of existing and new databases for density functional theory (DFT). It describes the procedures used to introduce A Collection of Chemistry DataBases (ACCDB) and its reduction to a smaller and statistically significant database called A Small(er) Collection of DataBase (ASCDB). Also, it presents an application of such databases in chemical education through the introduction of a notebook of twelve exercises that can easily complement a computational chemistry class. In addition, a new database of molecules having carbon-carbon long bonds (CLB18) is presented. Last, the databases are used in the …

Fabrication Of Mof Films Of Uio Or Pcn Type Through Layer-By-Layer Molecular Deposition As Well As Bulk Deposition For Catalytic Applications, John Ozdemir

Graduate Theses and Dissertations

Metal-organic frameworks (MOFs) are crystalline, porous materials comprised of symmetric organic linkers coordinated to positively charged metal atoms or metal oxide nodes. This dissertation uses strategies in crystal engineering to advance the study of functional MOFs with emphasis on thin film deposition. The first chapter of this dissertation will introduce the field of reticular chemistry to the reader and describe synthetic efforts to develop useful building blocks for MOF materials: namely porphyrin macrocycles and carboxylate capped zirconium-oxo and hafnium-oxo clusters. The building blocks for MOFs developed in the first chapter will be employed in the second and third chapters through …

Introduction Of Human Acidic Fibroblast Growth Factor (Fgf1) Variant With Increased Stability And Bioactivity, Azadeh Tavousi Tabatabaei

Graduate Theses and Dissertations

Human acidic Fibroblast Growth Factor 1 (FGF-1) involves in a broad spectrum of biological processes, including cell growth, proliferation, differentiation, migration, angiogenesis, wound healing, and embryonic development. hFGF1 non-selectively binds to cell surface hFGF receptor isoforms to elicit these cell-signaling processes. Since hFGF1 plays a significant role in tissue repair activity, that is a prime candidate for novel wound healing therapeutics. However, hFGF1 has been found to unfold near physiological temperature due to a strong electrostatic repulsion created by a dense cluster of positively charged amino acids near the c-terminus. The problem not only leads to proteolytic degradation of the …

Understanding Interfacial Reactions Initiating On Electrode Materials For Energy Storage Technologies, Jingnan Li

Graduate Theses and Dissertations

Since the first generation of lithium-ion batteries featured lithium cobalt oxide cathode and carbon anode commercialized in the 1990s, the high-capacity materials with lower cost are in demand to further increase the battery energy density. Lithium metal and silicon anode are promising high-capacity anode materials to achieve next-generation lithium batteries. However, both the materials actively react in electrolytes and suffer from dramatic volume change. Therefore, a reliable passivation layer at the electrolyte/electrode interphase (i.e., solid electrolyte interphase, or “SEI”) is required to support the long-term cycling of both materials. Cetrimonium hydro fluoride (CTAHF2) has been proposed and synthesized as an …

Colloidal Monolayers For Concentration Light In Ultra-Thin Semiconductor Layers, Rachel Cherry

Graduate Theses and Dissertations

Thin film semiconductors are used as photoconductive absorber layers for the development of broadband terahertz generation. Using a femtosecond laser pulse, the generation of a transient increase in the conductivity occurs by photoexciting conduction band electrons in the semiconductor. These thermalize through the emission of terahertz radiation. The route to terahertz generation is not particularly efficient as significant losses come from the absorption in the substrate that is beneath the photoconductive antenna layer. This work explores the application of hexagonally close-packed monolayers of chemically synthesized nanospheres as a potential light concentration method for ultra-thin films of GaAs and black phosphorus …

Role Of E168d In M. Tuberculosis Igps Catalysis, Hedda Booter

Theses, Dissertations and Culminating Projects

Mycobacterium tuberculosis is a bacterium that affects the lungs and causes tuberculosis, infecting over 10 million people worldwide each year. Owing to the organism’s evolving drug resistance, existing antibiotics no longer combat the disease. The need to discover new drug targets has never been greater. Previous findings suggest that the protein IGPS (indole-3-glycerol phosphate synthase) in M. tuberculosis (MtIGPS) may be a target in the treatment of the disease. MtIGPS catalyzes the fourth step in the tryptophan biosynthetic process. The ability to create their own tryptophan is a major advantage that many bacteria have. The role of E168, in the …

Hydrogen Technologies, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about hydrogen technology and the Energy & Environmental Research Center’s (EERC's) National Center for Hydrogen Technology. Includes information about hydrogen as an energy and fuel source and past EERC hydrogen projects.

Synthesis Of Fluorinated Monomers And Polymers For Various Applications, Cassandra J. Hager

All Dissertations

The world of industry utilizes a variety of polymers for various applications in many prominent fields. From electronics to food storage, the versatility of this class of chemistry has been widely proven. The Thrasher research group undertook a program dedicated towards the development of a library of fluorinated materials that focused on the synthesis and characterization of perfluoroalkoxy (PFA) copolymers of tetrafluoroethylene (TFE) and perfluoroalkyl trifluorovinyl ethers. One aim of the project was to improve upon the mechanical strength and wearability of commercial PFA resins by incorporating bulkier perfluoroalkoxy trifluorovinyl ether monomers into these copolymers. In addition to focusing on …

Light Harvesting And Electrically Conducting Metal-Organic Frameworks, Monica Gordillo Varela

All Dissertations

Composed of metal clusters nodes and organic linkers, metal-organic frameworks (MOFs) have emerged as versatile platforms with unparalleled chemical and structural tunability, synthetic facility, permanent porosity, and size-selective guest encapsulation capability. These features make them potential candidates for a variety of applications such as gas storage,drug delivery, catalysis,and sensing. In recent years, the introduction of redox- and photoactive components have yielded stimuli-responsive electronic and photonic MOFs and expanded their utility in molecular electronics and energy storage devices/technologies.

Chapter one describes the light-harvesting ability of a porphyrin-based MOF. Herein, we have demonstrated spontaneous solvothermal growth of [100]-oriented uniform pillared-porphyrin framework-11 (PPF-11) …

Liquid Chromatography With Tandem Mass Spectrometry Method Development For The Determination Of Β–Defensins In Bovine Milk, Symone T. Whalin

Masters Theses & Specialist Projects

Bovine mastitis, caused by a wide array of pathogens, results in a substantial economic loss for the dairy cattle livestock industry. β-defensins are a part of the bovine’s innate immune system and act as the first line of defense against mastitis. Only foundational research has been done on β-defensins’ ability to treat and prevent mastitis. There have been no analytical methods reported in the literature for analyzing β-defensins in bovine milk. This research aims to create an analytical approach to determine β-defensins in bovine milk. It is challenging to determine an analyte in a complex sample matrix, and milk is …

An Investigation Towards The Synthesis Of A Novel Conformationally Restricted Ethylenediamine Scaffold, Fanny Mai

Theses, Dissertations and Culminating Projects

This study reports the synthesis of a novel conformationally restricted ethylenediamine scaffold that can be explored for drug discovery. There was significant progress in synthesizing the target scaffolds, but future studies are needed to finish this synthesis. This potential ethylenediamine compound may offer new scaffolds for exploration in drug design and orexin receptor antagonists with improved selectivity for OX1R and OX2R.