Chemistry Commons^™

Evaluation Of A Radium-Thorium Disequilibrium Sediment Method Used To Model And Assess Porewater And Submarine Groundwater Exchange In The Coastal Marsh, Madeline R. Bodine

Theses and Dissertations

Ground, pore, and surface water exchange has been extensively studied in beach and near shore environments but has been long neglected in saltmarsh systems due to their complexity. Saltmarsh systems are of particular importance as they are the interface between fresh and saltwater. Saltmarshes impact carbon exchange, release and sequestration, and they process particulate matter. Understanding the characteristics of a marsh system such as the nutrient and particulate loads in conjunction with the flux of water exchange through the marsh provides a deeper understanding of these systems and can impact our understanding of the global water and carbon cycles, as …

Surface And Alloy Engineering Of Halide Perovskite (Cspbx3) Nanocrystals For Efficient And Stable Optoelectronics, Sakiru L. Abiodun

Theses and Dissertations

Organic and inorganic halide perovskite quantum dots (QDs) (in form of ABX₃, where A is organic cation e.g CH₃NH₃⁺ or inorganic cation e.g Cs⁺) have emerged as an intriguing alternative to the widely studied chalcogenide and pnictide QDs. Their excellent optoelectronic properties such as large absorption coefficient, high carrier mobility, wide color gamut, long electron-hole diffusion lengths, and tunable bandgap energy are largely responsible for their wide acceptability in various electronic devices. However, despite this enthusiasm, the problem of purification, long-term stability, lead toxicity and inadequate knowledge of their surface chemistry still …

Engineering Of Bio-Based And Synthetic Polymers: Synthesis And Application In Superabsorbent Materials And Antibacterial Agents, Jihyeon Hwang

Theses and Dissertations

A polymer consists of a large number of monomer units, which can be obtained naturally or via a chemical process called polymerization. Polymers are important materials that are used in our daily life. Life would not be possible without these polymers, either from plant biomass or petroleum-derived synthetic polymers. The substitution of petroleum-derived to biomass-based polymers has been highlighted to mitigate adverse environmental impact. However, the use of bio-based polymers is still a significant challenge for more demanding applications. In this dissertation work, the engineering of both bio-based and synthetic polymers and their properties are investigated.

In Chapter 1, the …

Structural And Immunological Characterization Of Inhaled Allergens And Their Complexes With Antibodies, Kriti Khatri

Theses and Dissertations

Allergy is an outcome of an allergen-antibody reaction (1). Potent airborne allergens from dust mites and pets are major causative factors for allergic conditions among predisposed individuals. Group-2 allergen Der p 2 from Dermatophagoides pteronyssinus is a major allergen which causes allergic conditions in more than 80% of mite-allergic subjects (2). Similarly, airborne allergen Can f 1 from dog (Canis familiaris) is also a major risk allergen which affects 10-20% of the population worldwide (3). Considering the increasing prevalence of inhalant allergens in the environment, antigenic characterization is crucial for improving allergy diagnostics and management. This study focuses …

Vaccinia Virus And Measles Virus As Oncolytic Vaccines: The Modulation Of The Viral Infectivity Via Surface Conjugations, Monchupa Kingsak

Theses and Dissertations

Oncolytic virus (OV) therapy has been shown to be an effective targeted cancer therapy treatment in recent years, providing an avenue of treatment that poses no damage to surrounding healthy tissues. Not only do OVs cause direct oncolysis, but they also amplify both innate and adaptive immune responses generating long-term antitumor immunity. However, a key challenge facing oncolytic virotherapy is neutralizing antibodies in vaccinated patients, leading to the viral clearance after systemic administration and failure in the treatment. The encapsulation of OVs using biocompatible polymers is one of the promising methods to prevent the viral clearance from antiviral immune responses. …

The Kinetic Control Of Polymer Micelles; Chemical Functionality, Material Interactions, And Equilibration, Taylor Larison

Theses and Dissertations

Polymer micelles have found significant uses in areas such as, energy storage devices, catalysis, opto-electronics, drug-delivery, oil additives, and nanoreactors. In many of these applications the overall micelle size (aggregation number) and chemical functionalization determines performance. To progress towards more advanced materials synthesized from the facile bottom-up approach with polymeric micelles the implementation and study of thermodynamic handles were investigated. Here the kinetic control of micelles was studied across a range of applications; independent control over micelle functionality, the spatial orientation of multiple metal oxide nanoparticles in mesoporous materials via self-assembly, and the use of small-angle neutron scattering (SANS) to …

Coordination Environment And Thermodynamics Of Colloidal Quantum Dots In Polar Solvents, Nuwanthaka Prasad Jayaweera Millaniyage

Theses and Dissertations

Colloidal semiconductor quantum dots (QDs) have been extensively investigated due to their attractive properties such as size-tunable absorption and emission spectra, large molar extinction coefficients, and significant photostability. These properties make them promising candidates for optoelectronic, photocatalytic, and biomedical applications. Common synthetic procedures of QDs produce nanocrystals capped with long-chain fatty acid derivatives which are stabilized in high boiling point solvents. Especially for bioimaging applications, the exchange of these native hydrophobic ligands with hydrophilic ligands should be performed, while preserving the smaller hydrodynamic radius. The coordination environment and thermodynamic parameters of the ligand exchanges should be carefully investigated to engineer …

Biochemical, Structural, And Immunological Characterization Of Selected Panallergens, Andrea Leigh O'Malley

Theses and Dissertations

Allergies throughout the world are increasing in prevalence and severity. Although the direct causes of the development of allergies are not confirmed, study of proteins that cause reactions will lead to a deeper understanding of allergy. This work focuses on three panallergen families, profilins, parvalbumins, and arginine kinases, to further elucidate the background of allergy from the point of view of the allergens themselves. In Chapter 1, we evaluate pollen, fruit, and mite profilins in the context of allergy, showing the relevance of conserved cysteine residues in stability and oligomerization as well as the first data on cross-reactivity between plant …

Reactive End Capped Polybenzimidazole Oligomers For High Temperature Thermosets And Improved Membranes For Electrochemical Devices, Caroline Marie Rohlfing

Theses and Dissertations

Polybenzimidazoles (PBI) are heterocyclic polymers that possess high thermal and oxidative stability. The inherent strength and chemical and thermal stability of PBI make it ideal for use in extreme environments; however, the current processing of PBI molded parts makes the process practically and economically unfavorable. These intrinsic properties make PBIs of particular interest for many industrial applications, varying from fabrics to membrane materials to molded parts. Processing these molded parts is extremely difficult, as the high glass transition temperature and extremely high melting point (>500°C) of PBI result in poor flow properties of PBI resins even at high temperatures. …

Expanding Tailorable Nanomaterial Synthesis With Persistent Micelle Templates, Eric R. Williams

Theses and Dissertations

The control of block polymer micelle dimensions while in solution is critical for a range of emerging applications in diverse fields from drug delivery and nanoreactors to use as sacrificial templates for porous nanomaterials. When under kinetic control, micelles will maintain a constant average size and thus aggregation number (N_agg) through the suppression of chain exchange mechanisms. Such kinetic control effectively enables the decoupling of micelle dimensions from solution conditions. In other words, kinetically trapped micelles can resist reorganizations brough about by e.g., the addition of metal nanoparticles. However, such micelles are traditionally governed by a fickle �� …

Sustainable Approaches To Photo-, Thermo-, And Electro-Chemical Reactions Of Amines, James David Sitter

Theses and Dissertations

In recent years, sustainable routes for chemical synthesis have garnered renewed interest. As the world continues to fight pollution and rising costs, it is imperative that new routes of synthesis that continuously fight the issues of pollution and waste are discovered, defined and explored. While traditional synthesis routes that require energy input typically require the burning of fossil fuels to produce heat, the amount of resources that go into the production of these fossil fuels and the sequestration of its waste to minimize its impact on the carbon footprint is enormous. Furthermore, sustainable chemistry research aims to decrease and minimize …

Structure Property Investigation And Applications Of Self-Assembled Triphenylamine Bis Urea Macrocycles, Md Faizul Islam

Theses and Dissertations

Porous organic crystals can be advantageous as nanoreactors and in sensing, separations, and storage. The Shimizu group utilizes bifurcated urea hydrogen bonding to direct the assembly small building block into pillars and columns affording functional porous crystals. Recently, our group has examined the incorporation of triphenylamines within the framework of bis-urea macrocycles. These macrocycles assemble into columns that contain the solvent of crystallization bound within the channels. Heating the crystals leads to removal of the solvent and activates the host for guest exchange by single-crystal-to-single[1]crystal transformations. Different electron accepting molecules can be encapsulated inside the pore of the host …

Molecular Devices For Measuring Weak Solvophobic Interactions And The Development Of Pedagogical Tools For Organic Chemistry Students, Alexander N. Manzewitsch

Theses and Dissertations

The main topics of this dissertation are: 1) the development and discussion of a new molecular balance for measuring alkyl-alkyl interactions in a wide array of organic solvents, 2) the development of linear solvation energy relationships between solvent interaction parameters and solvent accessible surface area (SASA) in CH-arene interactions, and 3) the development of online resources for helping undergraduate students perform organic chemistry mechanisms problems well.

The solvophobic effect, that is the forced association between two solutes due to intermolecular attraction of the solvent molecules, is ubiquitous in organic chemistry and responsible for many significant phenomena thereof. However, there is …

Hydrothermal Liquefaction Of Saccharina Latissima For The Production Of Biofuel, Mayokun A. Oke

Mechanical Engineering Theses

We performed hydrothermal liquefaction of brown macroalga (Saccharina latissima) in the presence of homogenous and heterogenous catalysts such as KOH, Na₂CO₃, Pd/C, HZSM-5, Ce/HZSM-5, and Ni/SiO₂-Al₂O₃ in hot compressed water, to investigate their effects on product yield and composition in the biocrude. To investigate hydrocarbon production, we used methanol as co-solvent (methanol-to-water 1/4 vol.%) and as the only liquefaction solvent. We carried out the experiments in a batch reactor at 330^oC and 120-130 bar, and varying temperature, algae-to-water ratio, residence time, and pretreatment method. The biocrude yields …

Mapping Per- And Polyfluoroalkyl Substances (Pfas) In South Carolina Surface Waters: Are There Hotspots?, Thomas C. Geiger

Senior Theses

Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals used in consumer products for their unique chemical properties. PFAS compounds are resistant to water, oil, heat, and grease, making them useful for a wide variety of everyday items such as non-stick cooking pans, food packaging, electronics, carpets, upholstery, paints, adhesives, and personal care products.¹ The resilient nature of PFAS has made these compounds immensely popular with consumers but has since been considered a potential environmental and public health hazard for their ability to bioaccumulate and for their stability in the environment. More than 6000 PFAS have been discovered in the …

Dipole Cooperativity And Polarization Frustration Determine The Secondary Structure Distribution Of Short Alanine Peptides In Water, Ying Yuan, Feng Wang

Chemistry & Biochemistry Faculty Publications and Presentations

The physical driving forces for secondary structure preferences of hydrated alanine peptide are investigated with B3LYP-D3(BJ) and the adaptive force matching (AFM) method. The AFM fit to the DFT surface, ALA2022, provides excellent agreement with the nuclear magnetic resonance scalar coupling constants from experiments. In turn, the model is used to gain insight into the physical driving forces behind secondary structure preferences of hydrated peptides. DFT calculations with and without the Conductor-like Screening Model (COSMO) show that the α helix is stabilized by solvent polarization due to dipole cooperativity. The two adjacent amide groups in β strand form a near-planar …

Computational Investigation Of Porphyrin-Based Host Design For Anions And Ion Pairs, Symphony Hill

Honors Theses

Little research has heretofore been devoted to studying the binding interactions between porphyrin-based molecular hosts and anions or ion pairs. Such interactions could be important in synthesizing molecules capable of detecting, binding, extracting, and transporting ions of biological, environmental, and industrial significance. With this in mind, computational studies of nine different porphyrin hosts were performed to examine the structural and binding properties of each molecule and potential ion guests. Using the Spartan computational chemistry software, each porphyrin was modeled and binding was tested with a number of ions of different shapes and sizes. Data was then collected regarding the distances …

Substituent Effect Analysis On Halogen Bonding Interactions, Summer Hanson

Honors Theses

This study was used to determine the significance of substituents placed on aromatic molecules and how electron-donating groups (EDG) and electron-withdrawing groups (EWG) affect the strength of the halogen bond. Each study involved the same substituents, each differing in electron-withdrawing and electron-donating capability. Five different systems were created on computational software to evaluate the distance between the halogen bond donor and halogen bond acceptor. In two studies, the goal was to find the best electron-donor on the halogen bond acceptor (donor of electron density) while the halogen bond donor remained constant. For one study, the goal was to determine the …

Development Of Innovative Multi-Drug Approaches To Counteract Illicit Drug Abuse In The Uae Population, Manal Ali Alhefeiti

Dissertations

The abuse of addictive substances is on the rise in the United Arab Emirates (UAE) population. Consequently, the UAE government spends about Dhs 5.5 billion annually on the rehabilitation of drug addicts. Blood, urine, and hair tests can reveal signs of sporadic or chronic drug use. Given the list of banned chemicals in the UAE, our main objective in this work was to develop a novel analytical method to identify and measure banned substances, especially prescription and over-the-counter drugs in the UAE. We developed and validated a rapid, sensitive and reliable liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) approach for the targeted …

A Microscopic Investigation Of Chemically Modified Membranes For Potential Oil Water Separation Applications, Latifa Rashed Al Nuaimi

Theses

Oil spills can have catastrophic impacts on both the environment and human society, an enormous oil spill known as the Deepwater Horizon Disaster happened in the Gulf of Mexico in April 2010 caused by an explosion of oil rig which started the catastrophe. It is achievable to reduce oil spills by developing and advancing technologies including gravity settling, centrifugation, gas flotation, coagulation, electrochemical, adsorption, and membrane filtration. There are many materials that can be used to form membranes, and each one has unique properties and advantages. The current study used the 3D printing porous membrane which is manufactured with an …

Nano-Supported Biocatalysts For Efficient Wastewater Remediation, Khadega Abobaker Al-Maqdi

Dissertations

The existence of various bioactive organic pollutants in wastewater and municipal water sources has raised concerns regarding their potential effects on human health. As a result, different techniques are being explored to effectively break down these persistent organic pollutants. Peroxidases have recently emerged as a new approach to remediation that may have advantages over traditional methods. However, evaluating the effectiveness of different peroxidases in breaking down various emerging pollutants can be time-consuming and difficult. In this study, a quick and reliable method was developed to test the degradability of 21 emerging pollutants by five different peroxidases (soybean peroxidase, chloroperoxidase, lactoperoxidase, …

Sharprazor: Automatic Removal Of Hair And Ruler Marks From Dermoscopy Images, Reda Kasmi, Jason Hagerty, Reagan Harris Young, Norsang Lama, Januka Nepal, Jessica Miinch, William V. Stoecker, R. Joe Stanley

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Background: The removal of hair and ruler marks is critical in handcrafted image analysis of dermoscopic skin lesions. No other dermoscopic artifacts cause more problems in segmentation and structure detection. Purpose: The aim of the work is to detect both white and black hair, artifacts and finally inpaint correctly the image. Method: We introduce a new algorithm: SharpRazor, to detect hair and ruler marks and remove them from the image. Our multiple-filter approach detects hairs of varying widths within varying backgrounds, while avoiding detection of vessels and bubbles. The proposed algorithm utilizes grayscale plane modification, hair enhancement, segmentation using tri-directional …

Using Capillary Electrophoresis To Quantify Competitive Binding Of Adsorbates To Silver Nanoparticles, Christopher D. Chung , '23

Senior Theses, Projects, and Awards

Silver nanoparticles (AgNPs) are increasingly used commercially and medically due to their antimicrobial and antibacterial properties. With increased use comes increased release of AgNPs into the environment, and once released, AgNPs can form coronas with molecules ranging from biomolecules to proteins to natural organic matter (NOM). The molecules in the corona adsorb to the surface of the AgNPs, drastically altering their innate properties such as cytotoxicity and binding behavior. In this study, we characterize and quantify model AgNP-adsorbate systems by obtaining their relevant reaction parameters through three different affordable analytical techniques, including dynamic light scattering (DLS), UV-vis spectroscopy, and capillary …

Biophysical And Structural Characterization Of Non-Canonical Dna Structures, Paul C. Seth , '23

Senior Theses, Projects, and Awards

G-quadruplex (GQ) and i-motif (iM) non-canonical DNA structures can be formed by G- and C-rich sequences within the genome, respectively. GQ and iM DNA play important roles in different biological processes and are promising therapeutic targets. Recently, the first left-handed GQ (LHGQ) was discovered and much remains to be learned about the structure and function of LHGQ DNA.

In this thesis, we investigate the biophysical and structural behavior of two LHGQ-forming sequences from the human genome, from the Human Solute Carrier 1 (SLC) and nuclear receptor binding SET domain (NSD) genes. We found that flanking bases play an important role …

Method Design For Separation Of Non-Canonical Dna Structures Via Capillary Electrophoresis, Erin V. Chen , '23

Senior Theses, Projects, and Awards

G-quadruplex DNA structures are highly relevant subjects of biochemical study, implicated in human diseases and cancer. Conventional methods for G-quadruplex DNA structure separation are time-consuming, environmentally unfriendly, and low throughput. Thus, there is a pressing need for alternative methods of separation to be developed for G-quadruplex DNAs. Here we present work in designing a separation method using the capillary electrophoresis instrument. Capillary electrophoresis is a highly automated, reusable, and quantitative technique that separates analytes based on their size and charge. A capillary method for G-quadruplex separation would be a valuable analytical tool to supplement the biophysical methods available by addressing …

Rage Inhibitors In Neurodegenerative Diseases, V. Prakash Reddy, Puspa Aryal, Pallavi Soni

Chemistry Faculty Research & Creative Works

Nonenzymatic Reactions of Reducing Sugars with Primary Amino Groups of Amino Acids, Proteins, and Nucleic Acids, Followed by Oxidative Degradations Would Lead to the Formation of Advanced Glycation Endproducts (AGEs). the AGEs Exert Multifactorial Effects on Cell Damage Leading to the Onset of Neurological Disorders. the Interaction of AGEs with the Receptors for Advanced Glycation Endproducts (RAGE) Contribute to the Activation of Intracellular Signaling and the Expression of the Pro-Inflammatory Transcription Factors and Various Inflammatory Cytokines. This Inflammatory Signaling Cascade is Associated with Various Neurological Diseases, Including Alzheimer's Disease (AD), Secondary Effects of Traumatic Brain Injury (TBI), Amyotrophic Lateral Sclerosis …

Toward The Yeast Surface Display Of Microviridin B, Jillian Leigh Stafford

Chemistry and Chemical Biology ETDs

Humans have turned to natural products for medicinal therapeutics for millennia. In recent years, the ribosomally synthesized and post-translationally modified peptide (RiPP) class of natural products have garnered a lot of attention due to their ability for heterologous expression, relative ease of mutation, and vast biological activates. Microviridins are a family of RiPPs that contain a tricyclic cage-like structure through the formation of two lactone rings and one lactam ring catalyzed by two ATP-grasp ligase family enzymes. Microviridins are potent inhibitors of serine proteases and mutational studies of a small number of residues indicates the potential of peptide engineering protease …

Aloe Barbadensis Rinds Employ Physical And Chemical Defense Mechanisms Against Insect Herbivores With Varying Success, Zachary Johnson, Ishveen Kaur, Fernando Castillo, Rupesh R. Kariyat, Debasish Bandyopadhyay

School of Integrative Biological & Chemical Sciences Faculty Publications

Plants deter herbivory through a suite of physical and chemical defenses. While most studies have focused on understanding one or the other, efficient plant defense against herbivory is often cumulative. To examine this, we used Aloe barbadensis (Asphodelaceae) as a model, since in natural settings, the species is found to be well-defended against insect herbivores. To start with, we hypothesized that the epicuticular wax potentially plays an important role in herbivore defense as the major physical defense. To test our hypothesis, we conducted bioactivity-guided extraction and polarity-based fractionation of A. barbadensis rinds. We then mixed them into an artificial diet, …

Pc-01 Synthesis Of Zinc Glycoconjugated Phthalocyanines As A Potential Phototherapeutic, Jessica A. Silva-Conejo, Katrina Mccarter, Tessa Greene, Joshua V. Ruppel

SC Upstate Research Symposium

Photodynamic Therapy (PDT) uses photosensitizers that are activated by light to produce singlet oxygen that can cause cell damage and potential cell death. Phthalocyanines are promising photosensitizers due to their absorption at clinically relevant wavelengths, meaning that they absorb at a wavelength that can penetrate deeper into tissues.

One challenge with using Phthalocyanines is that they have very low solubility in biological media. One potential approach to increase solubility is through glycoconjugation. Glycoconjugation can also be used as a strategy to increase selectivity toward targeted tissues. Glycoconjugated phthalocyanines can be synthesized using a copper catalyzed azide-alkyne cycloaddition reaction, otherwise known …

Considerations For Curricular Reform In Undergraduate Chemistry: Cooperative Adoption Factors, Modeling Social Influence, And Focusing On Specific Populations, Jacob D. Mcalpin

USF Tampa Graduate Theses and Dissertations

This dissertation will go through the details of three projects highlighting considerations for curricular reforms in undergraduate chemistry. Improving the teaching of chemistry is facilitated by considering the problem from multiple directions, namely, faculty and students. In addition to the multiple perspectives, this dissertation also seeks to bring new methodologies into the spotlight to improve the toolbox for other chemistry or discipline-based education researchers. Additionally, this dissertation has shown in several locations how focusing in on subgroups within populations can reveal findings that would not have been apparent from a global average of the population. The three project describes in …