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Functional Block Copolymers For Applications In Advanced Materials, Energy Storage, And Lithography, Christopher George Hardy

Theses and Dissertations

Block copolymers spontaneously self-assembly into a wide variety of ordered nanostructures on the length scale of 5 - 100 nm due to the thermodynamic immiscibility between the covalently linked, chemically distinct polymer chains. Incorporating desirable functional groups into block copolymer systems can lead to confinement of the functional group to a specific domain upon microphase separation of the block copolymer. The resulting materials display desirable characteristics of the functional group in a well-ordered nanostructure. Such systems have been utilized in a wide variety of applications including catalysis, ceramic materials, and membranes. This dissertation is focused on the synthesis, characterization, self-assembly …

Development And Figures Of Merit Of Microextraction And Ultra-Performance Liquid Chromatography For Forensic Characterization Of Dye Profiles On Trace Acrylic, Nylon, Polyester, And Cotton Textile Fibers, Scott James Hoy

Theses and Dissertations

Methodology for the microextraction of basic dyes on acrylic, acid dyes on nylon, disperse dyes on polyester, and reactive dyes, direct dyes, and indigo on cotton textile fibers is reported. Although these processes are destructive to the fiber evidence, the ability to analyze dye extracts from sub-millimeter fiber lengths of single fibers, coupled with detection limits in the hundred picogram range by ultra-performance liquid chromatography (UPLC) with both diode array detection (DAD) and tandem mass spectrometry (MS-MS) makes routine forensic characterization feasible.

Microextraction, followed by UPLC, can often distinguish similar fibers containing different, but similar, dyes with the combination of …

Silylation-Based Kinetic Resolution Of Α-Hydroxy Carbonyl Compounds And Synthesis Of Chiral Isothiourea Catalysts, Yan Zhang

Theses and Dissertations

The thesis describes the silylation-based kinetic resolution for α-hydroxy carbonyl compounds catalyzed by isothiourea catalyst as well as our effort to make novel chiral isothiourea catalyst.

In Chapter 1, general background will be introduced, including chirality, general methods to obtain enantiopure compounds and kinetic resolution. In Chapter 2, the mechanism of the chiral recognition was discussed and a novel isothiourea catalyst was design to investigate the mechanism. The synthesis of the new catalyst was also described in this chapter.

In Chapter 3, the silylation-based kinetic resolution for α-hydroxy carbonyl compounds will be discussed. Since silylation-based kinetic resolution have already been …

Plant Virus Based Materials For Cell Alignment And Differentiation, Elizabeth Balizan

Theses and Dissertations

This research focused on developing and using plant virus based scaffolds to understand substrate control over cell alignment and differentiation. The first part of this work centered on development of virus based patterns that were then used to align and elongate aortic smooth muscle cells (SMCs). Virus patterns were generated in capillary tubes via a simple drying method. Three experimental parameters were used to control pattern formation: (1) protein concentration, (2) salt concentration, and (3) hydrophobicity of the pre-deposition surface. By controlling these parameters several aspects of the final virus patterns were controlled. First, virus orientation was controlled. Patterns were …

A Silylation Based Kinetic Resolution Of Secondary Alcohols And The Synthesis And Structural Characterization Of Pyridyl-Oxazolidine Compounds, Cody Ian Sheppard

Theses and Dissertations

Described herein is the first enantioselective silylation based kinetic resolution of monofunctional secondary alcohols to achieve useful levels of enantioselectivity. Using commercially available reagents, the reaction conditions were optimized and found to successfully resolve several secondary alcohols with high enantioselectivity. It was discovered that the nucleophilic isothiourea compound (-)-tetramisole, with Ph3SiCl as the silyl source, gave superior results to other nucleophilic catalysts and was capable of performing the kinetic resolution in as little as 45 minutes using mild reaction conditions. The structural and electronic characteristics of successful and less successful substrates are also discussed.

Chapter three discusses mechanistic investigations and …

Investigations Of The Non-Covalent Ch-Π Interactions Using Molecular Torsional Balances, Chen Zhao

Theses and Dissertations

Several bicycle N-arylimide based molecular balances were designed to study aliphatic CH-pi interactions and aromatic CH-pi interactions (edge-to-face arene-arene interactions). In each case, the geometries of the interactions were characterized in the solid-state via X-ray analysis, and the strengths of interactions were characterized in solution by their folded/unfolded ratios, as measured by integration of their 1H NMR spectra.

The balances are very sensitive to variations in the strengths of weak non-covalent interactions. Several different aspects of the CH-pi interactions were studied, such as sterics, conformational entropy, cooperativity, deuterium isotope effect, substitution effects, and solvent effects. It showed that due to …

Characterizing Interactions Between Chromophores In Synthetic And Natural Macromolecular Films Via Maldi-Tof, Ibf And Dielectric Analyzer, Parul Jain

USF Tampa Graduate Theses and Dissertations

With the emergence of Matrix Assisted Laser Desorption/Ionization-Time-of-flight as a tool for diagnosis of diseases via proteomics, there is an increasing need for greater sensitivity. Analysis of peptides by MALDI-TOF-MS is affected by sample formulation and spotting onto a MALDI target. This dissertation investigates a novel MALDI sample preparation technique, Induction Based Fluidics (IBF), for depositing precise volumes (pL to nL) of samples onto the target. We have seen that while using IBF, the induced electric field accompanying deposition enhances matrix crystallization yielding smaller crystals with more homogeneity, as compared to conventional manual micropipette (MP) depositions. An investigation of the …

Novel Liquid Chromatography - Fourier Transform Mass Spectrometry (Ms) And Triple Quadrupole Ms Methods For The Determination Of Diarrhetic Shellfish Poisoning (Dsp) Toxins., Bébhine Carey

Theses

Harmful algal blooms (HABs) appear to be on the rise globally, which not only has a negative impact on the shellfish industry but can also cause human and animal intoxications. In order to advance our knowledge of HABs, specific and sensitive analytical methods are required to aid in monitoring shellfish and algal samples for biotoxins, harmful to consumers.

Identification Of A Histidine Metal Ligand In The Arge-Encoded N-Acetyl-L-Ornithine Deacetylase From Escherichia Coli, Wade C. Mcgregor, Danuta Gillner, Sabina I. Swierczek, Dali Liu, Richard C. Holz

Chemistry Faculty Research and Publications

The H355A, H355K, H80A, and H80K mutant enzymes of the argE-encoded N-acetyl-L-ornithine deacetylase (ArgE) from Escherichia coli were prepared, however, only the H355A enzyme was found to be soluble. Kinetic analysis of the Co(II)-loaded H355A exhibited activity levels that were 380-fold less than Co(II)-loaded WT ArgE. Electronic absorption spectra of Co(II)-loaded H355A-ArgE indicate that the bound Co(II) ion resides in a distorted, five-coordinate environment and Isothermal Titration Calorimetry (ITC) data for Zn(II) binding to the H355A enzyme provided a dissociation constant (K_d) of 39 μM. A three-dimensional homology model of ArgE was generated using the …

Molecular Docking And Nmr Binding Studies To Identify Novel Inhibitors Of Human Phosphomevalonate Kinase, Pornthip Boonsri, Terrence S. Neumann, Andrew Lawrence Olson, Sheng Cai, Timothy J. Herdendorf, Henry M. Miziorko, Supa Hannongbua, Daniel S. Sem

Chemistry Faculty Research and Publications

Phosphomevalonate kinase (PMK) phosphorylates mevalonate-5-phosphate (M5P) in the mevalonate pathway, which is the sole source of isoprenoids and steroids in humans. We have identified new PMK inhibitors with virtual screening, using autodock. Promising hits were verified and their affinity measured using NMR-based ¹H–¹⁵N heteronuclear single quantum coherence (HSQC) chemical shift perturbation and fluorescence titrations. Chemical shift changes were monitored, plotted, and fitted to obtain dissociation constants (K_d). Tight binding compounds with K_d’s ranging from 6–60 μM were identified. These compounds tended to have significant polarity and negative charge, similar to the natural …

Chemical Analysis Of Ophthalmic Solutions, Pagagiotis Tavlarakis

Seton Hall University Dissertations and Theses (ETDs)

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Refinement, Application, And Evaluation Of Cognitive And Affective Chemistry Measures For College Students, Keily Heredia

USF Tampa Graduate Theses and Dissertations

This work describes three case studies conducted to address two major problems in the area of chemistry education research, the lack of reported psychometrics regarding instrument scores, and the need for well-characterized assessments to evaluate college chemistry curricula.

The first case study describes a psychometric evaluation of the Colorado Learning Attitudes about Science Survey (CLASS), an instrument designed to assess student beliefs about the learning of chemistry. Results from this work suggest that the CLASS instrument provides fertile ground for short instruments with reasonable psychometric properties. Responses to a single scale instrument, created from CLASS, showed that students in an …

Chiral Phosphoric Acid-Catalyzed Acetalization And Iso-Pictet-Spengler Reactions, Matthew Jon Kaplan

USF Tampa Graduate Theses and Dissertations

The development of novel asymmetric reaction methodologies has been invaluable in both the academic and industrial world. In just 15 years, organocatalysis has provided a new means of developing asymmetric reaction methodologies using catalysts that are environmentally benign, relatively inexpensive, bench stable, and non-toxic. One development in organocatalysis that is important to our group in particular is chiral phosphoric acid-catalysis. BINOL-derived and VAPOL-derived phosphoric acids have proven to be excellent catalysts for a number of reactions.

The two projects I will discuss my efforts on are acetalization and iso-Pictet-Spengler reactions. These were projects that I performed during my first two …

Reaction Enthalpy And Volume Profiles For Excited State Reactions Involving Electron Transfer And Proton-Coupled Electron Transfer, William Antonio Maza

USF Tampa Graduate Theses and Dissertations

Electron transfer, ET, and proton-coupled electron transfer, PCET, reactions are central to biological reactions involving catalysis, energy conversion and energy storage. The movement of electrons and protons in either a sequential or concerted manner are coupled in a series of elementary reaction steps in respiration and photosynthesis to harvest and convert energy consumed in foodstuffs or by absorption of light into high energy chemi-cal bonds in the form of ATP. These electron transfer processes may be modulated by conformational dynamics within the protein matrix or at the protein-protein interface, the energetics of which are still not well understood. Photoacoustic calorimetry …

Computational Approaches For Structure Based Drug Design And Protein Structure-Function Prediction, Sai Lakshmana Kumar Vankayala

USF Tampa Graduate Theses and Dissertations

This dissertation thesis consists of a series of chapters that are interwoven by solving interesting biological problems, employing various computational methodologies. These techniques provide meaningful physical insights to promote the scientific fields of interest. Focus of chapter 1 concerns, the importance of computational tools like docking studies in advancing structure based drug design processes. This chapter also addresses the prime concerns like scoring functions, sampling algorithms and flexible docking studies that hamper the docking successes. Information about the different kinds of flexible dockings in terms of accuracy, time limitations and success studies are presented. Later the importance of Induced fit …

Asymmetric Nitrene Transfer Reactions With Azides Via Co(Ii)-Based Metalloradical Catalysis (Mrc), Jingran Tao

USF Tampa Graduate Theses and Dissertations

Asymmetric nitrene transfer reactions via metalloradical catalysis (MRC) with

azides has attracted research interest because of its fundamental and practical importance.

The resulting nitrogen-containing units are recurrent motifs in biologically important

molecules and can serve as versatile precursors in organic synthesis.

The [Co(D2-Por*)] have emerged as a new class of catalysts for asymmetric

aziridination and C-H amination. These metalloradical catalysts have been shown to be

highly effective for the asymmetric intermolecular aziridination of a broad scope of

substrates with different classes of azides with excellent to good enantioselectivity. The

intramolecular C-H amination utilizing various azides can allow for the construction …

Model Pt- And Pd-Based Electrocatalysts For Low Temperature Fuel Cells Applications, Selasi Ofoe Blavo

USF Tampa Graduate Theses and Dissertations

In the search for alternative energy technologies, low temperature fuel cells continue to feature as technologies with the most promise for mass commercialization. Among the low temperature fuel cells, alkaline and proton exchange membrane fuel cells are the most popular. Alkaline fuel cells have typically been used for water generation as well as auxiliary power for space shuttles. Their bulkiness however makes them undesirable for other applications, especially in automobiles, where there is a great demand for alternative technologies to internal combustion engines. Proton exchange membrane fuel cells on the other hand possess numerous qualities including their compact size, high …

The Spectrophotometric Analysis Of Lead Carbonate Complexation And Carbonate Saturation States In Seawater, Regina Anita Easley

USF Tampa Graduate Theses and Dissertations

The carbon dioxide (CO₂) system is the primary buffer in seawater which controls oceanic pH. Changes in the marine CO₂ system affect a number of processes such as metal speciation, mineral saturation states, auditory responses in fish, and primary productivity rates. Increased atmospheric concentrations of CO₂ from human activities (e.g. burning of fossil fuels, deforestation, and cement production) has led to a global decrease in surface ocean pH termed anthropogenic ocean acidification. One particular concern in response to increased oceanic CO₂ is a substantial decrease in the calcium carbonate (CaCO₃) saturation states, Ω …

Virtual Screening For Inhibitors Of Anti-Apoptotic Proteins: Dck, Bcl-Xl, Mcl-1, Mdmx, And Mdm2, Courtney Jerome Du Boulay

USF Tampa Graduate Theses and Dissertations

←Within this dissertation the topic of virtual screening is discussed with regard to three different cancer targets and also a brief introduction of the tools used in virtual screening. In Chapter 1, the reader will be introduced to virtual screening and the programs that are used in virtual screening. In Chapter 2, the first of three projects are discussed. This project consists of the work that was done to find inhibitors of the P53 binding domain of MDMX. In this project the mobility of residues within the binding site of MDMX are discussed and the ways in which we attempted …

Argumentation As A Lens To Examine Student Discourse In Peer-Led Guided Inquiry For College General Chemistry, Ushiri Kumarihamy Kulatunga

USF Tampa Graduate Theses and Dissertations

This dissertation work entails three related studies on the investigation of Peer-Led Guided Inquiry student discourse in a General Chemistry I course through argumentation. The first study, Argumentation and participation patterns in general chemistry peer-led sessions, is focused on examining arguments and participation patterns in small student groups without peer leader intervention. The findings of this study revealed that students were mostly engaged in co-constructed arguments, that a discrepancy in the participation of the group members existed, and students were able to correct most of the incorrect claims on their own via argumentation.

The second study, Exploration of peer leader …

Anti-Parasitic And Anti-Bacterial Agents: Studies On 1,4-Dihydropyridines And 2,4-Diaminoquinazolines, Kurt Steven Van Horn

USF Tampa Graduate Theses and Dissertations

Thirty-three 1,4-dihydropyridine diastereomeric pairs were synthesized and the structure-activity relationship studied in a Plasmodium falciparum in vitro model. Twenty-nine of these derivatives contained a 6-position oxygen, with 2.31, 2.32, 2.52 and 2.53 having single and double digit nanomolar activities. This SAR study revealed some insightful information about the 1,4-dihydropyridine substitution pattern. Substitution at the 7-position other than 3,4-dimethoxy severely reduced the activity. 4-phenyl substitution with 2- or 4- halo or methyl formed active compounds while substitution at the 3-position or with methoxy or conjugated aryl systems resulted in inactive compounds. The 2-position was found to majorly affect the activity, with …

Optimization, Modification And Application Of Gold Nanoparticles As The Substrates Of Surface Enhanced Raman Spectroscopy, Seongmin Hong

USF Tampa Graduate Theses and Dissertations

SERS

Synthesis Of Amphiphilic Α- And Γ-Aapeptides For Antimicrobial, Self-Assembly, And Mineralization Studies, Mohamad N. Amin

USF Tampa Graduate Theses and Dissertations

Seven novel, amphiphilic AApeptides were prepared. Two cationic, lipo-α-AApeptides, NA-75 and NA-77 were found to possess potent antimicrobial activity against Gram-positive bacteria, with almost no hemolytic activity. In addition to NA-75 and 77, four amphiphilic, γ-AApeptides, NA-133, 135, 137, and 139, and one anionic lipo-α-AApeptide, NA-81, were prepared for molecular self-assembly studies, with several interesting nanostructures observed by TEM. Mineralization of calcium carbonate from gaseous CO2 and Ca2+ in the presence of the 7 AApeptide amphiphiles was also observed by optical microscopy. Several AApeptides were found to be able to influence CaCO3 crystal morphology. Another α-AApeptide, NA-63, was synthesized by …

Urban Runoff Treatment Using Nano-Sized Iron Oxide Coated Sand With And Without Magnetic Field Applying, Mehdi Khiadani, Mansur Zarrabi, Maryam Foroughi

Research outputs 2013

Increase of impervious surfaces in urban area followed with increases in runoff volume and peak flow, leads to increase in urban storm water pollution. The polluted runoff has many adverse impacts on human life and environment. For that reason, the aim of this study was to investigate the efficiency of nano iron oxide coated sand with and without magnetic field in treatment of urban runoff. In present work, synthetic urban runoff was treated in continuous separate columns system which was filled with nano iron oxide coated sand with and without magnetic field. Several experimental parameters such as heavy metals, turbidity, …

Application Of Glycyrrhiza Glabra Root As A Novel Adsorbent In The Removal Of Toluene Vapors: Equilibrium, Kinetic, And Thermodynamic Study, Fazel Mohammadi-Moghadam, Mohammad Mehdi Amin,, Mehdi Khiadani, Fariborz Momenbeik, Heshmatollah Nourmoradi, Mohammad Sadegh Hatamipour

Research outputs 2013

The aim of this paper is to investigate the removal of toluene from gaseous solution through Glycyrrhiza glabra root (GGR) as a waste material. The batch adsorption experiments were conducted at various conditions including contact time, adsorbate concentration, humidity, and temperature. The adsorption capacity was increased by raising the sorbent humidity up to 50 percent. The adsorption of toluene was also increased over contact time by 12 h when the sorbent was saturated. The pseudo-second-order kinetic model and Freundlich model fitted the adsorption data better than other kinetic and isotherm models, respectively. The Dubinin-Radushkevich (D-R) isotherm also showed that the …

Development Of Improved Models For Gas Sorption Simulation, Keith Mclaughlin

USF Tampa Graduate Theses and Dissertations

Computational chemistry offers one the ability to develop a better understanding of the complex physical and chemical interactions that are fundamental to macro- and mesoscopic processes that are seen in laboratory experiments, industrial processes, and ordinary, everyday life. For many systems, the physics of interest occur at the molecular or atomistic levels, and in these cases, computational modeling and two well refined simulation techniques become invaluable: Monte Carlo (MC) and molecular dynamics (MD). In this work, two well established problems were tackled. First, models and potentials for various gas molecules were produced and refined from first principles. These models, although …

Creating New Superconducting & Semiconducting Nanomaterials And Investingating The Effect Of Reduced Dimensionality On Their Properties, Sukhada Mishra

Doctoral Dissertations

"The field of nanomaterials has continued to attract researchers to understand the fundamentals and to investigate potential applications in the fields of semiconductor physics, microfabrication, nanomedicine, surface sciences etc. One of the most critical aspects of the nanomaterials research is to establish synthetic protocols, which can address the underlying product requirements of reproducibility, homogenous morphology and controlled elemental composition. We have focused our research in exploring synthetic routes for the synthesis of superconducting and semiconducting nanomaterials and analyze their structure--property relationship through detailed characterizations. The first part of dissertation is focused on the synthesis of superconducting FeSe nanostructures using catalyst …

Analysis And Simulation Of Kinetic Model For Active Suspensions, Panon Phuworawong

Mathematics & Statistics Theses & Dissertations

In this research, we study the recently proposed kinetic model for active suspensions, where the active particles are assumed to be rigid rod and are driven in the suspension either by their own biological/chemical forces or external electric/magnetic fields. We first study the stability of the isotropic suspension in quiescent flow. Then we investigate the weak shear perturbation of the isotropic state and study some rheological properties of the suspension by explicit analytic formulas derived directly from the model. For imposed shear, we give some bifurcation diagrams of the stable states in some parametric spaces through numerical simulations. Some rheological …

Development Of Self-Assembling Mixed Protein Micelles With Temperature-Modulated Avidities, Allyson S.C. Soon, Michael H. Smith, Emily S. Herman, L. Andrew Lyon, Thomas H. Barker

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elastin-like polypeptides (ELPs) are polypentapeptides that undergo hydrophobic collapse and aggregation above a specific transition temperature, T_t. ELP diblocks sharing a common “core” block (I60) but varying “outer” blocks (A80, P40) were designed, where T_t,I < T_t,A < T_t,P. The formation of ~55 nm diameter mixed micelles from these ELP diblocks was verified using dynamic light scattering (DLS), multiangle light scattering (MALS) and fluorescence resonance energy transfer (FRET). To confer affinity to the blood circulating protein fibrinogen, a fibrinogen-binding tetrapeptide sequence (GPRP) was fused to A80-I60, while P40-I60 was fused to a non-binding control (GPSP). The …

Interaction Of Ceo2 And Zno Nanoparticles Towards The Symbiotic Association Of Alfalfa (Medicago Sativa) And Sinorhizobium Meliloti In Soil, Susmita Bandyopadhyay

Open Access Theses & Dissertations

The production of engineered nanoparticles (ENPs) has rapidly increased due to their wide range of applications in the field of electronics, medicine, chemistry and biology. Consequently, concerns have risen about the environmental release and potential negative impact of NPs. A few reports have described the effects of TiO2 NPs and quantum dots upon nitrogen fixing bacteria. However, the understanding of the interaction of NPs in plant-microbe interface (symbiotic association), like alfalfa (Medicago sativa L.)-Sinorhizobium meliloti, is still in its infancy. Alfalfa is the world's most important forage crop. It grows in association with S. meliloti, which is very important in …