Physical Sciences and Mathematics Commons^™

Understanding The Adsorption And Nucleation Of Transition Metals On A Model Carbon Support, Grant S. Seuser

Theses and Dissertations

Heterogeneous catalysis plays a vital role in the commercial production of chemicals. However, much is still unknown about the fundamental surface chemistry involved in catalyst preparation and the surface chemistry of the catalysts themselves. In the first part of this work, a surface science approach was employed to develop a fundamental understanding of the surface chemistry of strong electrostatic adsorption (SEA) of metal precursors on a model carbon support, highly oriented pyrolytic graphite (HOPG). SEA is a wet impregnation method in which anionic/cationic metal precursors are adsorbed onto positively/negatively charged functional groups by adjusting the pH of the solution above …

Iron Transport Machinery: A Potential Therapeutic Target In Escherichia Coli, Clorissa L. Washington – Hughes

Theses and Dissertations

Iron metabolism is an integral part of life for most organisms. Despite its essentiality, iron can also become toxic. There are many aspects to maintaining iron balance within the cell. The aim of this work is to provide insight into the function of several components involved in bacterial iron homeostasis. This work is significant for the development of novel antibiotics for treating resistant or pathogenic bacteria. Herein, it is shown that nickel can disrupt normal bacterial iron metabolism and that bacterial resistance can be affected by expression of iron acquisition genes. Once iron is obtained by the cell, it can …

Synthesis And Reactivity Of Carborane Backbone Pincer Complexes, Bennett J. Eleazer

Theses and Dissertations

In organometallic chemistry, boron-centered ligand systems represent a powerful synthetic strategy for the promotion of a variety of catalytic transformations. These ligands offer a versatile array of bonding motifs, which can function as borane, boratrane, boryl, borate, or borylenes type ligands, and are likely the strongest σ-donors in the anionic series of ligands based on boron, carbon, nitrogen, and oxygen. Carboranes, which are icosahedral boron clusters of the type C2B10H12, offer unique potential as metal ligands, such as their bonding to exohedral metal centers being dominated by two-center-two-electron σ-bond interactions, their three-dimensional cluster structure providing considerable steric shielding to a …

Multiple C-H Bond Activations Of Aromatic Compounds By Unsaturated Dirhenium Carbonyl Complexes, Poonam Dhull

Theses and Dissertations

The background and importance of aromatic C-H bond activation by metal complexes are discussed in Chapter 1 with the help of various examples from the literature. Synthesis of the dirhenium complex Re2(CO)8(-C6H5)(-H) 1.1 is also discussed in detail. It also includes work done on C-H activation on arenes and heteroarenes by previous members of Dr. Adams’ group. The reactions of Re2(CO)8(-C6H5)(-H) with naphthalene and anthracene yielding the first multiply-CH activated arene products by the multiple oxidative-addition processes are presented in Chapter 2. The reaction of Re2(CO)8(-C6H5)(-H) with itself yielded the doubly-Re2-metalated C6H4 bridged compound Re2(CO)8(µ-H)(µ-1,µ-3- C6H4)Re2(CO)8(µ-H), 2.3. The reaction of …

Hierarchical Corannulene-Based Materials, Allison M. Rice

Theses and Dissertations

Merging the intrinsic properties of fullerene (buckyball) and corannulene (buckybowl) derivatives with the inherent properties of crystalline metal- and covalentorganic frameworks (MOFs and COFs), including their modularity, porosity, versatility, high surface area, and structural tunability, opens a pathway to unlock a novel class of fulleretic materials. Despite the great interest in MOFs and COFs, as well as fullerene derivatives, this dissertation is focused on crystalline fullerene- and corannulenecontaining frameworks, highlighting their potential contributions in the fields of optoelectronic devices, electrodes, and photosensitizers. We have revealed a dual role of fullerene- and corannulene-containing building blocks showing their versatility to act as …

Synthesis And Characterization Of Biomimetic Dinuclear And Tetranuclear Copper Complexes, Syed Rahmath Ullah Joy

Masters Theses

Seven new copper(II) complexes were prepared from the condensation reaction of 4-tert-butyl-2,6-diformylphenol with two equivalents of bis(pyrazolyl)ethanamine or 3,5-dimethyl-bis(pyrazolyl)ethanamine moieties in the presence of two equivalents of various copper(II) starting materials having different counter ions (i.e. acetate - AcO^-, perchlorate - CIO₄^-, tetrafluoroborate - BF₄^-, nitrate - NO₃^-, and chloride - Cl^-). The resulting copper(II) complexes were characterized in solid state by single crystal X-ray crystallography, and in solution by UV-Vis and ESI/MS spectroscopies.

X-ray crystallographic studies showed that in solid state two types of …

Pd-Based Photocatalysts For Sonogashira C-C Cross-Coupling Reactions, Komadhie Charuka Dissanayake

Masters Theses

Sonogashira C-C cross-coupling reaction has been heavily used for its simplicity, flexibility and value. Although the original Sonogashira C-C cross coupling reaction conditions entail the use of 0.5 mol% of Pd catalyst, 2 mol% of Cul as co-catalyst at room temperature, the experimental conditions used in laboratories to prepare some compounds vary substantially, especially with respect to the reaction time, temperature and loading amount of the catalysts. The most significant drawback of the conventional Sonogashira reaction is the use of Cul as it leads to the formation of homocoupling product when the reaction is exposed to air or oxidizing agents. …

Determination Of The Oxidative Capacity Of Soot Toward Gsh And Characterization Of Soot Physicochemical Properties, Kaylee Troth

All Master's Theses

Fine atmospheric particulate matter (PM_2.5) emitted during the combustion of fossil and biomass fuels is known to adversely affect human health. While the underlying mechanisms are thought to be driven by the generation of reactive oxygen species (ROS), specific particle characteristics responsible for this detrimental effect are not well understood. In this research, the quantitative determination of the biologically relevant antioxidant, glutathione (GSH), was optimized for use as an indicator of oxidative stress to shed light on relevant particle characteristics. This was accomplished via fluorescent spectroscopy for GSH determination by way of reaction with o-phthalaldehyde (OPA), a …

Key Enzymes In Cancer: Mechanism Of Action And Inhibition With Anticancer Agents, Debasish Bandyopadhyay, Gabriel Lopez, Stephanie Cantu, Samantha Balboa, Annabel Garcia, Christina Silva, Diandra Valdes

Chemistry Faculty Publications and Presentations

Several enzymes play significant role in different stages of cancer including proliferation, invasion, metastasis and angiogenesis. Mechanism of actions of a few key enzymes along with their inhibitors have been discussed with particular attentation to riboneucleotide reductase, thymidylate synthease, topoisomerase II, interleukins, cell survival proteins and aminopeptidase N.

Identification Of Chemical Compounds That Inhibit The Function Of Histidyl-Trna Synthetase From Pseudomonas Aeruginosa, Yanmei Hu, Stephanie O. Palmer, Sara Robles, Tahyra Resto, Frank Dean, James M. Bullard

Chemistry Faculty Publications and Presentations

Pseudomonas aeruginosa histidyl-tRNA synthetase (HisRS) was selected as a target for antibiotic drug development. The HisRS protein was overexpressed in Escherichia coli and kinetically evaluated. The KM values for interaction of HisRS with its three substrates, histidine, ATP, and tRNAHis, were 37.6, 298.5, and 1.5 μM, while the turnover numbers were 8.32, 16.8, and 0.57 s-1, respectively. A robust screening assay was developed, and 800 natural products and 890 synthetic compounds were screened for inhibition of activity. Fifteen compounds with inhibitory activity were identified, and the minimum inhibitory concentration (MIC) was determined for each against a panel of nine pathogenic …

Cellulose Modification For Use As Reinforcement In Bio-Based Composites, Ashley L. Rudolph

Electronic Theses and Dissertations

The goal of the research contained in this thesis is to provide an alternative method of developing polymers than the current petroleum-based polymeric products. Vegetable oil-based polymers are a popular alternative due to their low-cost and low toxicity. The carbon-carbon double bonds in the oil are ideal reactive sites for a free radical polymerization. Cellulose is a naturally occurring polymer. Modifying cellulose prior to making composites with tung oil allows a hydrophilic material to mix better with a hydrophobic resin. Vegetable oil-based polymers usually require the reinforcement of fibers to enhance the thermo-mechanical properties that would replace petroleum-based polymers. In …

Alkali Cation Effects On Redox-Active Formazanate Ligands In Iron Chemistry, Daniel L J Broere, Brandon Q. Mercado, Eckhard Bill, Kyle M. Lancaster, Stephen Sproules, Patrick L. Holland

Daniel Broere

Supplemental Information: Alkali Cation Effects On Redox-Active Formazanate Ligands In Iron Chemistry, Daniel L J Broere

Daniel Broere

No abstract provided.

Hyperpolarized Porous Silicon Nanoparticles: Potential Theragnostic Material For 29si Magnetic Resonance Imaging, Hyeonglim Seo, Ikjang Choi, Nicholas Whiting, Jingzhe Hu, Quy S. Luu, Shivanand Pudakalakatti, Caitlin Mccowan, Yaewon Kim, Niki Zacharias Millward, Seunghyun Lee, Pratip Bhattacharya, Youngbok Lee

Nicholas Whiting

Sure Poster 2018, Stephanie Armas, Cody Autrey, Enrique J. Blanco Martinez, Jared Church, Swadeshmukul Santra, Woo Hyoung Lee, Karin Y. Chumbimuni-Torres

Cody Autrey

Brett Taubman.Jpg

Dr. Brett Taubman

No abstract provided.

Brett Taubman In Lab.Jpg, Brett Taubman

Dr. Brett Taubman

No abstract provided.