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Synthesis, Crystal Structure And Ionic Conductivity Of Ruddlesden-Popper Oxide Materials: Effects Of Ionic Radii And Defects On Lithium-Ionic Conductivity., Selorm Joy Fanah Dec 2021

Synthesis, Crystal Structure And Ionic Conductivity Of Ruddlesden-Popper Oxide Materials: Effects Of Ionic Radii And Defects On Lithium-Ionic Conductivity., Selorm Joy Fanah

Electronic Theses and Dissertations

Layered perovskite oxides of the Ruddlesden-Popper (RP) type structure can be good lithium-ion conductors for solid electrolyte applications in all-solid-state batteries, due to the large gap separating octahedral layers which can be useful pathways for Li-ion conduction. However, little work has been done on their lithium-ion transport properties in these materials despite their interesting structural properties. This work highlights the synthesis and study of the ionic conductivities in a series of n = 2 and 3 Ruddlesden-Popper oxides, as part of an ongoing investigation in search of alternative solid electrolyte materials. Several different strategies were employed for the enhancement of …


Theoretical Investigation Of The Co-C Bond Activation In Methylcobalamin And Adenosylcobalamin-Dependent Systems: Mechanistic Insights., Arghya Pratim Ghosh Dec 2021

Theoretical Investigation Of The Co-C Bond Activation In Methylcobalamin And Adenosylcobalamin-Dependent Systems: Mechanistic Insights., Arghya Pratim Ghosh

Electronic Theses and Dissertations

The vitamin B12 derivates, otherwise known as cobalamin (Cbl), are ubiquitous organometallic cofactors. The biologically active forms of Cbl, such as methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl), act as cofactors in different physiological reactions for both prokaryotes and eukaryotes. A crucial aspect of the Cbl-mediated systems is the activation of the organometallic Co-C bond that plays a critical role in its catalytic activity. One of the most remarkable features of this Co-C bond is its unusual activation in AdoCbl-dependent enzymatic reactions, where a trillion-fold rate acceleration of the Co-C bond cleavage is observed inside the enzyme compared to the isolated …


Computational Investigations Of The Photochemical Properties Of B12-Dependent Systems: From Solution To Enzymes., Megan Toda Mackintosh Dec 2021

Computational Investigations Of The Photochemical Properties Of B12-Dependent Systems: From Solution To Enzymes., Megan Toda Mackintosh

Electronic Theses and Dissertations

The photochemical properties of the B12 family of molecules (cobalamins = Cbls) have been known for many years yet only until the 21st century have applications for the light-sensitivity of Cbls come to the surface. Photolabile Cbls can be used for the delivery of therapeutics with spatial and temporal control, in the generation of hydroxyl radicals, and in nature, as demonstrated in the catalytic cycle of coenzyme B12-dependent photoreceptors. This dissertation describes the use of computational methods to explore the photochemical properties of Cbl systems including antivitamins B12, a thiolato-cobalamin, and the coenzyme B …


Electrochemical Characterization Of Surface-Immobilized Metal Nanostructures: Stability, Atomic Level Doping, Catalysis, And Sensing Applications., Badri Prasad Mainali Aug 2021

Electrochemical Characterization Of Surface-Immobilized Metal Nanostructures: Stability, Atomic Level Doping, Catalysis, And Sensing Applications., Badri Prasad Mainali

Electronic Theses and Dissertations

This dissertation has two main themes. The first theme involves voltammetric analysis of the stability of Au nanoparticles (NPs) under electrochemical and thermal treatment as a function of size, ligand stabilizer, and atomic composition. The second theme involves the use of Au NPs, electrophoretic deposition (EPD), and anodic stripping voltammetry (ASV) for electrochemical detection of analytes. The electrochemical size stability of 4.1, 15.1, and 50.3 nm average diameter Au NPs upon treatment with multiple electrochemical oxidation-reduction cycling in acidic electrolyte is monitored by observing changes in the peak oxidation potential (Ep) in ASV and the electrochemically measured surface …


Investigations Of Elastin Recoil On Molecular And Macroscopic Levels., Nour Mohammad Jamhawi Aug 2021

Investigations Of Elastin Recoil On Molecular And Macroscopic Levels., Nour Mohammad Jamhawi

Electronic Theses and Dissertations

Elastin is one of the most hydrophobic proteins, and it is extremely flexible when hydrated. The driving force for recoil is the decrease in entropy of the protein and/or the hydrating solvent. This dissertation is a study of both mechanisms. Following an introduction (Chapter 1), Chapters 2 and 3 investigate the recoil mechanism on the molecular level in the hydrating solvent and in the protein, respectively. Chapter 4 examines macroscopic properties of recoil by thermomechanics. Conclusions are discussed in Chapter 5. Using double quantum NMR, the deuterated water ordering at the elastin surface was studied quantitatively as a function of …


Micellar Nanocatalysis For Efficient Reactions., Uyen T Duong Aug 2021

Micellar Nanocatalysis For Efficient Reactions., Uyen T Duong

Electronic Theses and Dissertations

Water is considered a green, sustainable, and inexpensive solvent for organic synthesis. However, performing organic reactions in water is especially challenging due to the inherent insolubility of substrates and catalysts. Inspired from Nature, where chemistry happens in water, micellar catalysis has recently gained much attention, especially for applications in pharmaceutical industry. Aqueous micelles are generally formed by amphiphile`s self-aggregation, a particular class of molecules possessing both hydrophobic and hydrophilic components. The aqueous micelle contains a hydrophobic cavity, which allows the lipophilic substrates and catalyst to go inside micelles, allowing their much higher localized concentration that enhances the reaction rates and …


Recent Studies On The Synthesis Of Medicinal Molecules., Paige Monsen Aug 2021

Recent Studies On The Synthesis Of Medicinal Molecules., Paige Monsen

Electronic Theses and Dissertations

Medicinal chemistry interfaces synthetic organic chemistry, natural product chemistry and chemical biology, with a goal of yielding therapeutic agents. Natural products or compounds derived from natural sources such as plants, animals, and microorganisms, are often biologically active and render that compound a likely drug lead. For thousands of years humankind has utilized natural products for medicinal purposes and consequently scientists take advantage of both these compounds’ core structural characteristics and their modes of actions on selected targets as inspiration to develop therapeutics. Because the total synthesis of such complex molecules can be cumbersome and expensive, semi-synthetic methods on isolated natural …


Synthesis, Characterization, And Catalytic Activity Of Functionalized Metal Bis(Thiosemicarbazones)., Caleb Aaron Calvary Aug 2021

Synthesis, Characterization, And Catalytic Activity Of Functionalized Metal Bis(Thiosemicarbazones)., Caleb Aaron Calvary

Electronic Theses and Dissertations

Bis-(thiosemicarbazones) are a class of ligands that have found a wide range of uses from electrocatalysts to medicinal and diagnostic reagents. These ligands contain a diimine backbone, N2S2 chelating core, and pendent amines. In order to further explore this class of ligands, the previously underreported transamination reaction, which exchanges one pendent amine group for another, was utilized to create several derivatives using aliphatic and aromatic amines. The transamination reaction is appealing alternative to making the desired thiosemicarbazide. Further appeals come from the fact that it is a one-pot reaction that gives highly pure products in good yields. …


Mass Spectrometry Based Metabolomics And Lipidomics., Fang Yuan Aug 2021

Mass Spectrometry Based Metabolomics And Lipidomics., Fang Yuan

Electronic Theses and Dissertations

Metabolomics and lipidomics studies are important to understand living organisms at the molecular level. In this dissertation, I conducted various untargeted and targeted metabolomics and lipidomics studies using mass spectrometry based analytical platforms. Firstly, I investigated the androgen depletion effects on fecal metabolites in a mouse model of systemic lupus erythematosus and metabolite biomarkers for colorectal cancer using two-dimensional gas and liquid chromatography-mass spectrometry. Secondly, I investigated the relationship between gut microbiota-mediated resistance and susceptibility to malaria and the production of short-chain fatty acids using gas chromatography-mass spectrometry. Thirdly, I developed a high-throughput liquid chromatography-mass spectrometry method to profile long-chain …


Photophysics Of Substituted [1,4]Benzodioxino[3,2-B]Oxanthrene (Bdo) Chromophores And Their Macromolecules: A Spectroscopy And Density Functional Theory Study., Abdelqader M. Jamhawi Aug 2021

Photophysics Of Substituted [1,4]Benzodioxino[3,2-B]Oxanthrene (Bdo) Chromophores And Their Macromolecules: A Spectroscopy And Density Functional Theory Study., Abdelqader M. Jamhawi

Electronic Theses and Dissertations

Chromophores and macromolecules containing [1,4]benzodioxino[3,2-b]oxanthrene (BDO) has attracted attention since the beginning of this century. Previous studies demonstrated their potential in wide range of applications including gas permeability, hydrogen and energy storage, sensing, and catalysis. Better understanding of the geometrical and electronic structure characteristics of BOD-based chromophores is vital to advance their employment in these applications. This work utilizes spectroscopy techniques coupled with density functional theory methods to provide this required understanding. Substituted BDOs exhibit red-shift of >1 eV in their electronic transitions compared to unsubstituted BDOs. This shift is explained by a molecular orbital reorganization induced by the substituents. …


Micelles And Lipid Nanoparticles: Catalysis And Biomedical Application., Faisal Ibrahim Aug 2021

Micelles And Lipid Nanoparticles: Catalysis And Biomedical Application., Faisal Ibrahim

Electronic Theses and Dissertations

RNA-based therapeutics is a rapidly expanding field due to its enormous potential for treatment of diseases through knockdown of genes or expression of therapeutic proteins. However, due to the overall negative-charge of an RNA molecule, RNA-based therapeutics must rely on delivery systems to overcome the various biological barriers for ultimate release of an RNA payload into the cytosol. Over the past three decades, the development of lipid-based RNA delivery systems, especially lipid nanoparticles (LNPs), have been comprehensively studied due to their unique properties. LNPs represent the most widely used delivery systems for RNA-based therapeutics, as evidenced by the clinical approvals …


Oriented External Electric Field (Oeef) Tuning Of Unsubstituted Azoheteroarene Photoswitching Performance., Irma Avdic May 2021

Oriented External Electric Field (Oeef) Tuning Of Unsubstituted Azoheteroarene Photoswitching Performance., Irma Avdic

College of Arts & Sciences Senior Honors Theses

Azoheteroarenes are relatively new photoswitchable compounds, where one of the phenyl rings of an azobenzene molecule is replaced by a heteroaromatic five-membered ring. Although few studies have been performed, recent findings on methylated azoheteroarenes show that these photoswitches have great potential in various optically addressable applications. Thermal stability of molecular switches is one of the primary factors considered in the design process. For the purposes of quick information transmission in materials science, the thermal (Z – E) relaxation process should be as short as possible. On the other hand, molecular memory storage devices prefer long Z - E relaxation times. …