Physical Sciences and Mathematics Commons^™

Synthesis And Evaluation Of Gallate Esters As Alternatives To Traditional Parabens, Marcia Reeves

Longwood Senior Theses

Parabens are esters of p-hydroxybenzoates that are commonly found in everyday consumer products as well as pharmaceuticals. They are often used in commercial products to prevent bacterial growth as well as to provide extended shelf life, but they have been shown to activate estrogen receptors in vivo, a contributing factor in human breast cancer proliferation. Our lab has previously generated a multitude of paraben derivatives that do not exhibit estrogenic activity. Many of these derivatives may have other safety concerns, but gallate esters appear to have the least hazardous properties. The estrogenic, antimicrobial, and antioxidant properties of the gallate ester …

Synthesis And Characterization Of Enantioenriched Deuterated And Fluorinated Small Molecules, Mitchell D. Mills

Master's Theses (2009 -)

The development of novel deuterated and fluorinated bioisosteres has significantly impacted the pharmaceutical and agricultural industry and created a growing demand for new synthetic methodology. Both deuterated and fluorinated small molecules exist at the forefront of drug discovery due to their unique ability to attenuate the pharmacokinetic properties of new and currently existing drugs. Selective, high-throughput methods for deuteration and fluorination are scarce in the literature, especially methods that introduce D or F atoms asymmetrically. Benzylic CH bonds are oftentimes key sites for enzymatic manipulation in metabolic processes, alteration of CH bonds to CD or CF bonds at the benzylic …

A Comparative Study Of Two Nickel-Based Suzuki-Miyaura Hybrid Molecular Catalysts, Mollie Morrow

Senior Theses

Two molecular nickel-based catalysts, (2,2’bipyridine-4,4’-carboxylic acid)nickel(II) chloride and (2,2'-bipyridine-4,4'-diamidopropylsilatrane)nickel(II) chloride, were synthesized and subsequently attached to a solid support in the form of amorphous silicon dioxide to create two hybrid molecular/heterogeneous catalysts. Characterization using ICP-MS and ATR-FTIR confirms that both catalysts are bonded to the SiO₂ support. The catalysts were both able to catalyze a Suzuki-Miyarua cross-coupling which their molecular counterparts were unable to; the carboxylate catalyst was able to achieve yields of 10% and the silatrane catalyst achieved yields of up to 50%. Post-reaction analysis indicated that while some catalyst desorption occurred in both complexes, active catalytic species …

Metal Free Bond Activation By Carboranyl Phosphines, Gayathri B. Gange

Theses and Dissertations

In the past few decades, main group-based catalysts have attracted increasing attention as an alternative approach to overcome the most prevailing issues of transition metal catalysts such as high cost, toxicity, and low abundance. Among these main groupbased catalysts, Phosphine based compounds have shown a variety of bond activations due to the strong nucleophilicity from their congener species. To the contrary, unique electron deficient boron-based clusters have the tendency to accept two electrons reversibly due to their electron deficiency. In this study, we have synchronized the electron donor ability of the phosphine with the electron acceptor ability of the ortho …

Well–Defined Donor–Acceptor Materials, Gabrielle A. Leith

Theses and Dissertations

The modularity of multivariant scaffolds such as covalent–organic frameworks (COFs) provides an unprecedented level of control in the alignment of donor (D) and acceptor (A) units, a demand that is driven by the production of optoelectronic, photonic, and spintronic devices. The foray into novel motifs bearing D-A ensembles in frameworks has been applied towards material property modulation for device performance enhancement. This dissertation presents an emerging trend in the development of D-A interfaces by highlighting recent advances probing D-A interactions in porous crystalline matrices and co-crystals, with a focus on energy transfer (ET) and charge transfer (CT) processes in pre-designed …

Photophysics And Electronic Properties Of Photochromic Metal-Organic Frameworks, Corey R. Martin

Theses and Dissertations

Modulation of materials properties through light-based illumination has the capability to expand the technology sector due to stimuli-responsive dynamic behavior that cannot be achieved in traditional materials. For example, reversibly tuning photophysical profiles of such materials allows for switching between discrete states that is a key aspect for the developing logic gates, spatially- and temporally-resolved sensors, and on-demand drug delivery systems. My efforts have focused on employment of metal-organic frameworks (MOFs) as a versatile platform for the material development which contain photochromic moieties allowing for tailoring their electronic properties. Our group has expanded this direction to include heterometallic and actinide-containing …

Sustainable Polymers: Upcycling Poly(Vinyl Chloride) And Mimicking Low Density Polyethylene, Ian Baxter

Theses and Dissertations

In this research, increasing the sustainability of polymers was investigated through two main methods. The upcycling of poly(vinyl chloride) and the creation of polymer mimics to create degradable low-density polyethylene. In the first chapter, an overview of the sustainability issues of polymers is presented and approaches are described on how their sustainability may be increased through the upcycling of polymers or the synthesis of degradable polymers that mimic the properties of petrol-based polymers.

Chapter 2 contains the progress on the upcycling of PVC using high oleic soybean oil. Soybean oil can soften PVC making it less brittle than pure PVC. …

A Damaged Reputation: Nuclear Depictions In Entertainment Media, Alexander Cannon

Chemistry & Biochemistry Student Scholarship

This paper, originally written for Dr. Adamus Liotta in an honors chemistry class, explores the possibility of a significant influence over public common sense found in the depictions of entertainment media. Through careful analysis and interpretation of Godzilla, The Simpsons, Fallout, and Call of Duty, this paper finds a synergy throughout this diverse range of audience, medium and historical origin, which culminates in an effect much greater than the sum of its parts. This effect frames nuclear science, of any kind, in a hyperbolically catastrophic and horrific light, reinforcing an excessively cautious, pessimistic public perspective on nuclear technology …

Mechanistic Understanding Of Catalytic Processes For Sustainable Chemical Transformations, Pooja J. Ayare

Theses and Dissertations

The current field of catalysis is notably advanced in terms of both conceptual and technical innovation. There is a constant need to design new catalysts and develop catalytic processes to improve the scope, efficiency, and selectivity of various chemical transformations. It is also imperative to design catalytic systems which are effective, truly-recyclable and energy efficient for a sustainable future. This can be done through comprehensive knowledge and understanding of catalyst behavior, reaction kinetics and process designing.

For most industrial processes, the preferred catalysts are heterogeneous because these solid catalysts can be easily separated from the final product. However, they often …

Cooperative Allosterism In Avidin And Streptavidin Upon Biotin Binding As Observed By Changes In Intrinsic Fluorescence, Alycia Murphy

Celebration of Scholarship 2022

Avidin is a homotetrameric protein known for its high binding affinity and specificity for biotin which gives it great functionality in many biotech applications. Prior research on the bacterial analog, streptavidin found cooperative allosterism exhibited in the binding process. This research was aimed at investigating whether this same cooperative allosterism accompanies the binding of biotin to avidin. This work measured intrinsic tryptophan fluorescence as biotin was titrated into avidin. A blueshift in the wavelength of maximum fluorescence as well as quenching of the overall fluorescence intensity, similar to the streptavidin was observed. The saturation point for 335 nm emission (tryptophans …

Block Copolymer Directed Self-Assembly: Exploring The Efficacy Of Applications In Semiconductor Fabrication, Jakin Bryce Delony

USF Tampa Graduate Theses and Dissertations

Over the course of the past 80 years, semiconductor devices have become increasingly ubiquitous in everyday life.From constructing mainframes that encompassed entire rooms during the 1940s, to inventing personal computers in the 1980s, to developing progressively faster smartphones and wearable technology in the 2010s, the primary driving force behind the Digital Revolution has been increasing transistor counts, and thus computing power, via incremental improvements in optical lithography. In 1965, Intel co-founder Gordon Moore boldly predicted that the transistor density of semiconductor devices would double approximately every 18-24 months. While this prediction -- now colloquially referred to as Moore's Law -- …

Phosphorus And Metal Cycling In A Drinking Water Source, Amanda Modica

Senior Theses and Projects

This project sought to investigate the cycling of phosphorus and metals in Lake Auburn, a drinking water source, specifically to analyze the impacts of an alum treatment on the lake for the purpose of decreasing concentrations of eutrophication-promoting phosphorus. The alum addition was performed in the summer of 2019 in two phases. Water samples were collected from the surface to the deepest point at five sites around the lake from February 2019 to November 2021. Data showed that the added alum slowly sank to the bottom of the lake. Total and dissolved metals data showed increased metals concentrations at sampling …

Honey As A Biomonitor For Air Pollutant Deposition In The Eastern United States Using Ion Chromatography And Scanning Electron Microscopy, Cole Cochran

Undergraduate Honors Theses

Anthropogenic activities generate metal, acid, and particulate air pollutants which negatively impact human and ecological health. In the United States, power plant, industrial, and vehicle emissions are leading causes of air pollution, however, the measurement of air pollution at high-resolution spatial regimes remains a challenge. Honey has emerged as a powerful biomonitoring tool to effectively quantify contaminants without the need for a large array of monitoring instruments. I hypothesized that honey could be used to effectively measure and map modern air pollutant spatiotemporal relationships over the Eastern U.S. Using ion chromatography with sulfate as an indicator for air pollution and …

Intrinsic Photodynamic Study On Photocatalytic Materials, Wenhui Hu

Dissertations (1934 -)

To relieve the global energy crisis and environmental pollution caused by the combustion of traditional fossil fuels, developing an environmental-friendly renewable energy to replace fossil fuel is urgent. Among the possible energy sources, solar energy has attracted numerous attentions because of the abundant storage. However, it is challenging to efficiently utilize and store solar energy. One attractive strategy to address this challenge is to convert solar energy to fuel through artificial photosynthesis (e.g. photocatalytic water splitting to generate H2). A technologically significant solar-driven water splitting system requires an efficient photocatalytic system that can not only effectively harvest light but also …

Modification Of Active Sites In Catalytic Materials For Gas-Phase Heterogeneous Catalysis, Deependra Man Shakya

Theses and Dissertations

Heterogeneous catalysis remains at the core of chemical manufacturing industries with 80-90 % of chemical processes relying on the use of catalysts. Unlike homogeneous catalyst that has extremely well-defined active sites, active sites in heterogeneous catalysis are complex and show dynamic behavior under reaction conditions, and change their structures, composition, particle size. The complexity associated with these systems has made the rational design of the catalyst a difficult problem. Highly crystalline metalorganic frameworks (MOFs) as heterogeneous catalysts present the unique opportunity to systematically modify the geometries, ensemble sizes, and compositions of highly dispersed active sites due to their tailorable, and …

Tailored Nanomaterials For Advancing Fast-Charge Research, Wessel Van Den Bergh

Theses and Dissertations

The demand for fast, energy-dense storage has driven research into nanoscale intercalation materials. Nanoscale materials not only accelerate kinetics but also can modify reaction path thermodynamics, intercalant solubility, and diffusivity. Pioneering works have revealed such nanoscale changes, often without the need to separately probe each fundamental transport process. While electrodes can be designed to have one transport processes dominant, there remain opportunities to better understand energy-dense designs with multiple concomitant transport constraints. The contents herein highlight emerging an method using tailored, energy-dense nanomaterials and the process of elimination to clearly correlate architectural features to performance. For example, this method revealed …

A Proposed Treatment Of Mixed Connective Tissue Disease By Competitive Inhibition Of Autoantibodies, Thomas Russell

Senior Honors Theses

Mixed Connective Tissue Disease is an autoimmune disease characterized by Raynaud’s phenomenon and arthritis among other symptoms. It is primarily caused by antibodies that target the U1-RNP 70K peptide. The treatment proposed in this paper uses competitive inhibition to prevent the binding of the anti-U1-RNP 70K antibodies with the U1-RNP 70K peptide. A method for testing the designed treatment in silico is proposed using AutoDock Vina docking software.

The Development Of Inhibitors For Sars-Cov-2 Orf8, My Thanh Thao Nguyen

CSB and SJU Distinguished Thesis

An unexpected outbreak of SARS-CoV-2 caused a worldwide pandemic in 2020. Many repurposed drugs were tested, but there are currently only three FDA approved antivirals (Merck’s antiviral Molnupiravir, Pfizer’s antiviral Paxlovid, and Remdisivir).1 Most of the antiviral drugs tested SARS-CoV-2 main protease and RNA-dependent RNA polymerase. However, it is important to explore different drug targets of SARS-CoV-2 to prepare for the virus mutations of the future. This research looks at an alternative approach in which SARSCoV- 2 Open Reading Frame 8 (ORF8), which has been shown to be a rapidly evolving hypervariable gene, was chosen to be the protein of …

Sars-Cov-2 Main Protease Inhibitors Repurposed For Hiv-1 Protease Binding, Jacob Minkkinen

CSB and SJU Distinguished Thesis

Severe acute respiratory syndrome (SARS-CoV-2) led to the COVID-19 global pandemic, with over 460 million cases of infection and over 6 million deaths since the start of the pandemic. SARS-CoV-2 is a retrovirus that utilizes a main protease (Mpro). Mpro is a catalytic cys/his protease. Several treatments were proposed to stop the pandemic including repurposing drugs to inhibit the Mpro. Another retrovirus that uses a protease is human immunodeficiency virus (HIV-1) which has been a global epidemic for 40 years and is a devastating disease that attacks the immune system. HIV-1 has infected 79.5 million people and has killed an …

Synthesis And Characterization Of Aluminum Complexes Implementing Redox-Active Nitroxide Bidentate Ligands, Omar Saleh , '22

Senior Theses, Projects, and Awards

Aluminum is an abundant, sustainable, and non-toxic metal, which would be a great candidate to be used in redox and catalytic chemistry in lieu of the currently used heavy metals. However, aluminum can only exist over one stable oxidation state, which is a major obstacle in this pursuit. To tackle this issue, the Graves Lab has been focusing on incorporating redox active ligands into aluminum complexes. Nitroxide (NO⁻) is an exceptionally important functional group, as it can reversibly exist over three stable oxidation states. In this work, I synthesized and characterized neutral aluminum complexes, [(^(OMe)pyNO)AlMe₂]₂ (1b) and [(^(OMe)pyNO)AlMe₂]AlMe₃ (2b), with …

Exploring The Kinetics And Thermodynamics Of O–H Bond Activation By Tripodal Tris(Nitroxide) Aluminum And Gallium Complexes, Joseph S. Scott , '22

Senior Theses, Projects, and Awards

Aluminum is one of earth’s most abundant and cheapest metals, and it is also nontoxic and environmentally friendly. This makes it an ideal candidate to be implemented in organometallic chemistry as a greener alternative to metal-based systems based on heavy and/or precious metals. One of the realms in which aluminum and other group 13 elements show promise is metal-ligand cooperative chemistry, which can afford transition metal-reminiscent small molecule activation chemistry. Our studies of organic ligands with nitroxide-functionalities within Al and Ga coordinative systems has led us to the discovery of tripodal tris(nitroxide) Al and Ga complexes with abilities to engage …

Design And Application Of Membrane Nanodiscs For Biophysical Studies Of Influenza A Proteins, Aye K. Kyaw , '22

Senior Theses, Projects, and Awards

Membrane proteins play a range of important roles in biological systems, yet they are underrepresented in the data base of high-resolution structures of all proteins. There is intense interest in developing new methodologies for studying membrane proteins. An essential step to membrane protein method development is devising reliable membrane mimics in which to embed membrane proteins. The goal of this thesis was to develop and apply nanodisc membrane mimics to the study of an influenza A membrane protein called M2. Nanodiscs provide a lipid bilayer environment with access to both sides of the bilayer and are smaller than commonly used …

Synthetic, Photophysical, And Catalytic Studies Of Light-Harvesting Macrocyclic Complexes, Fox Bratcher

Masters Theses & Specialist Projects

Chromophores are an important class of compounds in Nature and industry, with several hundred thousand tons produced annually as dyes and pigments. Alone, these compounds absorb light unto themselves; however, several of these compounds can be combined to produce a beneficial cascading transfer of energy to a core chromophore.

In this study, photophysical properties of several covalent and axially borondipyrromethene (BODIPY)-conjugated complexes of porphyrin and salphen scaffolds have been evaluated in a series of emission and catalytic studies. In the porphyrin systems, a beneficial excited energy transfer (EET) from the BODIPY moieties to the porphyrin core was observed; however, only …

Towards Semiconductor Nanorods With Nickel/Iron Cocatalyst., Kehinde Ayorinde

Masters Theses & Specialist Projects

The adverse effects associated with the utilization of fossil fuels has led to the need to provide an alternative cleaner energy. Photocatalytic hydrogen evolution reaction via water splitting provides a renewable pathway to generating energy. Our photocatalyst system includes a semiconductor component (CdSe/CdS core/shell nanorods) to capture light and an attached metal (cocatalyst) for the hydrogen evolution reaction. Platinum is an effective metal catalyst for this reaction due to strong proton binding energy that easily facilitates the reduction of water to produce hydrogen gas. However, due to the high cost of platinum, there is a need to find a less …

The Utilization Of Volatile Organic Compounds And Human Leukocyte Antigen Genes For Ethnic-Specific Differentiation Within Target Populations, Alice Breia Boone

FIU Electronic Theses and Dissertations

Human scent has been previously defined as a complex mixture of volatile organic compounds (VOCs) detected in the headspace above a scent sample. Humans generate odor from several areas of the body including hair, mouth, hand, axillae, and foot. Due to the novelty of human scent research, human scent evidence has been undervalued in the court of law. However, this type of evidence has significant value when physical evidence is not available at crime scenes. To increase the individualization and differentiation power of human scent evidence, this study aimed to further investigate the identification of chemical signatures within axillae of …

Attempted Synthesis & Antibacterial Properties Of Apt-6k Against Ndm-1 K. Pneumoniae, Alec Bofetiado

Honors Theses

NDM-1 K. pneumoniae is a highly resistant bacterial organism that is capable of causing debilitating nosocomial infections in immunocompromised patients. Only "last-resort" antibiotics--such as colistin--work against this organism. Therefore, new antibiotics are needed to help fight against these types of infections. APT-6K is a novel compound that was demonstrated to be effective against MRSA with nanomolar concentrations in a prior study. Novel methods of APT-6K synthesis and its testing for antibiotic effects against NDM-1 K. pneumoniae were attempted in this research. APT-6K synthesis was unsuccessful. Commercially-prepared APT-6K also did not demonstrate growth inhibition against NDM-1 K. pneumoniae nor against a …

High-Octane Gasoline Production Processes Using Catalysts Containing Platinum, Dilnoza Mauletbayevna Ametova, Duysenbay Xojabayevich Abdikamalov, Edil Abilov

Karakalpak Scientific Journal

The catalytic reforming process is designed to increase the detonation resistance of gasolines and to obtain individual aromatic hydrocarbons, mainly benzene, toluene, xylenes - petrochemical feedstocks. It is important to obtain a cheap hydrogen-containing gas in the process for use in other hydrocatalytic processes. The importance of catalytic reforming processes in oil refining increased significantly in the 1990s. due to the need to produce unleaded high-octane gasoline

Trends In The Development Of Industrial Sector Of Uzbekistan, Bakhtiyar Kalmuratov, Aydos Bekbosinov

Karakalpak Scientific Journal

The article presents the main directions of industrial transformation at the new stage of economic reforms in 2016-2020. The key achievements during this period in the development of manufacturing industry production and exports, the development of industrial and territorial structures, and the improvement of market mechanisms for the development of commodity markets are highlighted.

Socio-Economic Factors Of Environmental Problems, Manzura Kamalova, D. Shakenov

Karakalpak Scientific Journal

People consciously and intensively rebuild their nature according to their own needs, creating rural and urban areas in which they live. People care about the quality of life in the context of the unity of nature and culture. Social is a relatively new discipline that deals with urban space and environmental issues. One way to imagine what is beneficial to people is to find out what is economically best for the person. The article examines the economic factors that form the attitude towards social ecology in Kazakhstan. The article concludes that society should cooperate to achieve common things, both for …

Toward Bioinspired Polymer Adhesives: Activation Assisted Via Hobt For Grafting Of Dopamine Onto Poly(Acrylic Acid), Erik M. Alberts, P.U. Ashvin Iresh Fernando, Travis L. Thornell, Hannah E. George, Ashyln M. Koval, Manoj K. Shukla, Charles A. Weiss Jr., Lee C. Moores

Student Publications

The design of bioinspired polymers has long been an area of intense study, however, applications to the design of concrete admixtures for improved materials performance have been relatively unexplored. In this work, we functionalized poly(acrylic acid) (PAA), a simple analogue to polycarboxylate ether admixtures in concrete, with dopamine to form a catechol-bearing polymer (PAA-g-DA). Synthetic routes using hydroxybenzotriazole (HOBt) as an activating agent were examined for their ability in grafting dopamine to the PAA backbone. Previous literature using the traditional coupling reagent 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to graft dopamine to PAA were found to be inconsistent and the sensitivity of EDC coupling …