Chemistry Commons^™

Two-Photon Excitation Based Photochemistry And Neural Imaging, Kevin Andrew Hatch

Open Access Theses & Dissertations

Two-photon microscopy is a fluorescence imaging technique which provides distinct advantages in three-dimensional cellular and molecular imaging. The benefits of this technology may extend beyond imaging capabilities through exploitation of the quantum processes responsible for fluorescent events. This study utilized a two-photon microscope to investigate a synthetic photoreactive collagen peptidomimetic, which may serve as a potential material for tissue engineering using the techniques of two-photon photolysis and two-photon polymerization. The combination of these techniques could potentially be used to produce a scaffold for the vascularization of engineered three-dimensional tissues in vitro to address the current limitations of tissue engineering. Additionally, …

Modulation Of The Physiological And Biochemical Effects Of Copper Nanoparticles In Kidney Beans (Phaseouls Vulgaris) Treated By Kinetin, Suzanne Annette Apodaca

Open Access Theses & Dissertations

It is imperative to not only understand the impact of engineered nanomaterials (ENMs) in edible plants, but also the interactions they have with various additives used in agriculture. In this study, kidney bean plants were grown in potting soil treated with nano copper (nCu), bulk copper (bCu), and copper chloride (CuCl2) at concentrations of 0, 50, and 100 mg/kg for 55 and 90 days. At 15 days of growth, 0, 10, and 100 μm of kinetin (KN) were applied to plants. Plant tissue samples were harvested at 55 days and seeds were reaped at 90 days. Physiological and biochemical parameters …

Synthesis And Characterization Of Uranyl Dipyrrin Complexes For Environmental Applications, Duer Bolotaulo Bolotaulo

Open Access Theses & Dissertations

Persistent organic pollutants (POPs) are toxic chemicals that adversely affect the health of human populations as well as the environment. The need to develop remediation methods and materials as well as understand the mechanisms in which they can degrade POPs is necessary. Furthermore, heterogeneous phase metal based catalysts in place today do not fully understand the chemistry underlying degradation processes. The proposed research seeks to synthesize and characterize uranyl dipyrrin complexes to assess and understand the reactivity of uranyl dipyrrins with pollutants. Photophysical and electrochemical techniques will be used to characterize and determine the viability of utilizing the uranyl complexes …

New Organosilicon Chemistry, Paulina Elena Gonzalez Navarro

Open Access Theses & Dissertations

The formation of siloxymethylamine intermediates R3SiOCH 2NMe2, 1, as initial products of the reduction of DMF by hydrosilanes catalyzed by Mo(CO)5NMe3 has been reported. These siloxymethylamines can react with R’3SiH to form trimethylamine and disiloxanes, and with chlorosilanes to form disiloxanes and ClCH 2NMe2, Eschenmoser’s salt. I shall illustrate, in Chapter 1, how attempts to react 1, formed in situ in the presence of chlorosilanes R’3SiCl in the hope producing heterosilyl disiloxanes, R3SiOSiR’3, was not successful but led to a newly discovered activation of the Si-Cl bond by DMF.

In Chapter 2, we surmised that 1 acts as a transient …

Paleolithic Protection In A Western World: A Look Into Preagricultural Nutrition As A Remedy For The Diseases Of Civilization, Emilie R. Caron

Honors Theses

The aim of this investigation is to discover the associations of the Western diet to noncommunicable diseases and to determine if a reversion to a Paleolithic diet will provide treatment and prevention of these diseases. Noncommunicable diseases, otherwise known as Diseases of Civilization, are lifestyle influenced diseases and encompass obesity, diabetes mellitus, cardiovascular disease, and associated cancers. Incidences of these diseases have skyrocketed in the past century and show no signs of decline. Since 1900, the death rates due to heart disease and cancer have risen to account for 47% of total deaths in the United States in 2010. (Tippett, …

The Synthesis Of Poly(Propylene Fumarate), Brian N. Fitch

Williams Honors College, Honors Research Projects

Poly(propylene fumarate) is a promising material in the field of bone tissue engineering. A recently described chain growth polymerization was developed for the synthesis of poly(propylene fumarate). This pathway uses the ring-opening polymerization of maleic anhydride and propylene oxide with magnesium ethoxide as an initiator to yield poly(propylene maleate). The poly(propylene maleate) was then isomerized to poly(propylene fumarate) using diethyl amine. In order to scale up the reaction to a 20L reactor, several optimizations of the purification schemes was required. The main optimizations were done to the purification of poly(propylene maleate). Several methods were tested including replacing the water washes …

An Investigation Of The Adsorption Behavior Between Silver Nanoparticles (Agnps) And Corundum (Α-Al2O3) At Environmental Ph Values Using Inductively-Coupled Plasma Optical Emission Spectroscopy (Icp-Oes) And Raman Spectroscopy, Kevin Andrew O'Neil

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With the increased use of silver nanoparticles (AgNPs) in consumer products, the need to monitor their release into environmental soils has become critical. Although minerals make up a large component of soils, research on their interactions with AgNPs is still limited. Furthermore, the majority of the existing research focused on silica-based minerals rather than metal oxides, which is the second most abundant mineral type in the earth's crust. This study examined for the first time the aqueous interaction between the widely used, spherical Creighton AgNPs and a-corundum (a-Al2O3), a representative non-silica-based mineral, at environmentally relevant pH values (6-11). Samples were …

Theoretical Estimation Of PkA'S Of Pyrimidines And Related Heterocycles, Rachael Ann Wessner

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Pyrimidines and related heterocycles are an important class of compounds with a wide variety of applications. As a result, there is great interest in the chemical properties of these compounds, specifically their pKa's. Despite the importance of these compounds their reported pKa's are often only approximations or are completely absent from literature. Experimentally measuring pKa's can be challenging, especially if the pKa is below zero. Alternatively, pKa's can be estimated computationally using a Quantitative Structure-Activity Relationship (QSAR). However, most of the compounds included in this study exist as two or more forms that arise from tautomerism. Tautomerism complicates the estimation …

Synthesis, Characterization, And Properties Of Peroxo-Based Oxygen-Rich Compounds For Potential Use As Greener High Energy Density Materials, Nipuni-Dhanesha Horadugoda Gamage

Wayne State University Dissertations

One main aspect of high energy density material (HEDM) design is to obtain greener alternatives for HEDMs that produce toxic byproducts. Primary explosives lead azide, lead styphnate, and mercury fulminate contain heavy metals that cause heavy metal poisoning. Leaching of the widely used tertiary explosive NH4ClO4 into groundwater has resulted in human exposure to ClO4– ions, which cause disruptions of thyroid related metabolic pathways and even thyroid cancer. Many research efforts to find replacements have gained little success. Thus, there is a need for greener HEDMs. Peroxo-based oxygen-rich compounds are proposed as a potential new class of greener HEDMs due …

Vapor Deposited Cr-Doped Zns Thin Films: Towards Optically Pumped Mid-Infrared Waveguide Lasers, Eric A. Karhu, Charles R. Ildstad, Stefano Poggio, Vedran Furtula, Nikolai Tolstik, Irina T. Sorokina, Joseph J. Belbruno, Ursula J. Gibson

Dartmouth Scholarship

Compact, affordable mid-IR lasers require the development of gain materials in waveguide form. We report on the high vacuum deposition of Cr:ZnS films with concentration ranging from 10¹⁸-10²⁰ dopants/cm³ . At low concentrations, films display well-isolated absorption associated with substitutional Cr²⁺ ions in the lattice. Spatial modulation of the dopant concentration suppresses the absorption associated with this substitution. Lateral crystallite sizes less than 30 nm are associated with the lowest substrate temperatures (<50 °C) used during deposition, and waveguide losses as low as 8dB/cm are observed. These materials are promising candidates as gain media for fabrication of waveguide mid-IR lasers.

Size And Chemistry Selective Membranes From Block Polymer Templates, Ryan A. Mulvenna

Open Access Dissertations

The use of block polymers continues to gain attention with their myriad applications in industry for advanced applications in biology, medicine, electronics, and separations. The ability of block polymers to self assemble into ordered states on the nanometer level makes these materials suitable for applications that mandate structural order on this scale. By tuning the chemistry of these block domains, we may explore their utilization for advanced separations.

In this dossier, we detail the efforts into the controlled radical polymerization of polyisoprene-b-polystyrene-b-poly( N,N-dimethylacrylamide) (PI-PS-PDMA) via. a facile reversible addition-fragmentation chain transfer (RAFT) mechanism. For this …

A Molecular Docking Study On Alphavirus Nsp3 Macrodomains, B. Danger Davies

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Mass Spectrometric Analysis Of Biologically Relevant Compounds Hyphenated By Gas And High Performance Liquid Chromatography, Zach Laswell

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Conversion Of Crude Glycerol Using Clostridium Pasteurianum Into Butanol, Stephen Morgan

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Analyzing Urine In Mice With Tyrosinemia Type 1 Using Nmr Spectroscopy, Emily Olsen

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Optimizing Solvent Blends For A Quinary System, Thomas L. Hoy

Williams Honors College, Honors Research Projects

The Department of Polymer Engineering had received a grant from the Keck foundation to produce a process in which hundreds of copolymers can be formulated, synthesized, analyzed and then extrapolated to produce the optimal polymer for the desired material property. This process involves synthesizing approximately fifty polymers in a custom apparatus, none of which necessarily have the same monomer components. This leads to issue of which solvent or blend of solvents to use that would sufficiently dissolve both monomers and the resulting copolymer. If the monomers are not completely dissolved, a homogenous reaction will be impossible and if the copolymer …

Awareness Of Clinical Laboratory Sciences And Shortage Of Clinical Laboratory Scientists In The 21st Century, Cynthia Funnye Doby

Walden Dissertations and Doctoral Studies

Retiring baby boomers and the lack of interest and awareness among college students to enroll in an accredited Clinical Laboratory Science (CLS) program have created a shortage of CLS professionals in the 21st century. The U.S. Bureau of Labor Statistics predicts 18,000 CLS vacancies by 2018. However, only about 5,000 students graduate from accredited CLS programs each year. The purpose of this study was to explore students' perceptions of allied health professions and factors that influenced students and CLS professionals to select CLS as a profession. Bandura's social cognitive career theory served as the theoretical framework for this phenomenological study. …

Non-Conventional Approaches To Syntheses Of Ferromagnetic Nanomaterials, Dustin M. Clifford

Theses and Dissertations

The work of this dissertation is centered on two non-conventional synthetic approaches to ferromagnetic nanomaterials: high-throughput experimentation (HTE) (polyol process) and continuous flow (CF) synthesis (aqueous reduction and the polyol process). HTE was performed to investigate phase control between Fe_xCo_1-x and Co_3-xFe_xO_y. Exploration of synthesis limitations based on magnetic properties was achieved by reproducing M_s=210 emu/g. Morphological control of Fe_xCo_1-x alloy was achieved by formation of linear chains using an H_ext. The final study of the Fe_xCo_1-x chains used DoE to …

Sol-Gel Assembly Of Metal Nanostructures Into Metallic Gel Frameworks And Their Applications, Xiaonan Gao

Theses and Dissertations

The advent of nanoscience and nanotechnology has sparked many research forefronts in the creation of materials with control over size, shape, composition, and surface properties.^1,2 However, for most of the applications, nanoscale materials need to be assembled into functional nanostructures that exhibit useful and controllable physical properties. Therefore, numerous efforts on the assembly of nanoparticles (NPs) using organic ligands, polymers and polyelectrolytes have been reported.^3,4 However, the interactions between NPs are mediated by intervening ligands, which are detrimental to charge transport and limit the thermal stability. Hence, developing a new method to produce solid …

Design And Application Of Facile Routes To N-Heterocycle Functionalized Poly(Arylene Ether)S, Abraham K. Kemboi

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A series of 3,5-difluorinated systems, which are activated towards nucleophilic aromatic substitution (NAS) by the strongly electron withdrawing benzoxazole or benzothiazole groups, located meta to the fluorines were prepared and fully characterized. The monomers also carry various N-heterocyclic species on the non-fluorinated ring. The corresponding poly(arylene ether)s, some of which were copolymers with triphenylphosphine oxide-based monomers, were prepared via standard NAS polycondensation reactions. Incorporation of the monomers containing N-heterocycle units was determined by NMR spectroscopy. Characterization of the thermal properties was done using thermogravimetric analysis (TGA) and differential scanning (DSC). Most of the polymers displayed good film forming properties when …

Synthesis And Characterization Of Peek Analogues Utilizing 3,5- And 2,4-Difluorobenzophenone., Zachary Ewing

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Two routes to semi-crystalline, potentially functionalizable poly(ether ether ketone), PEEK, analogues were explored using varying percentages of 4,4’-difluorobenzophenone and either 3,5-difluorobenzophenone or 2,4-difluorobenzophenone as the electrophilic component in nucleophilic aromatic substitution polycondensation reactions with hydroquinone. PEEK analogues utilizing 3,5-difluorobenzophenone were carried out in a “one-pot” fashion and their properties were compared to the same materials prepared previously by a multi-step synthetic procedure. The use of 2,4-difluorobenzophenone led to completely new PEEK analogues. The polymers were characterized via NMR spectroscopy, Size Exclusion Chromatography, Thermogravimetic Analysis, and Differential Scanning Calorimetry. Molecular weight determinations showed the synthesized polymers to be of a variety …

Alkylenedioxy Containing Peek Polymers Containing Meta Linkages, James Uchenna Ohaeri

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The oxyalkylene containing, meta linked monomers 1,2-bis(3-(4-fluorobenzoyl)phenoxy)ethane, 1,3-bis(3-(4-fluorobenzoyl)phenoxy)propane, 1,4-bis(3-(4-fluorobenzoyl)phenoxy)butane, 1,5-bis(3-(4-fluorobenzoyl)phenoxy)pentane can be prepared by a three-step process starting with the dialdehydes (1,2-bis(3-formylphenoxy)ethane, 1,3-bis(3-formylphenoxy)propane, 1,4-bis(3-formylphenoxy)butane and 1,5-bis(3-formylphenoxy)pentane, respectively). Polymerization of the monomers with bisphenol-A gave soluble, thermally stable amorphous poly(ether ether ketone)s. The polymers exhibited molecular weights of (Mw/Mn) (21,841/ 8721) g/mol, (21,195/ 7569) g/mol, (9,107/ 2819) g/mol and (12,990/ 4723) g/mol, respectively. Thermal analyses of the polymers revealed Tgs of 112º, 106º, 92º and 91º, respectively and 5% weight losses under a nitrogen atmosphere of 389º, 410º, 411º and 414º, respectively.

Routes To 1,3,4 - Oxadiazol-2(3h)-Ones, Karunakar Reddy Madaram

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Various 1,3,4-oxadiazol-2(3H)-ones were synthesized by reaction of the bromocarbonylhydrazine salt(35) obtained from treatment of 4-bromo-3-phenylsydnone(34) with HCl with the corresponding acid chlorides in DME. The structures were confirmed by their physical, analytical and spectral data (IR, GC/MS, 1H and 13C NMR and CHN analysis). In general these compounds were synthesized in good to excellent yields and it is planned to continue exploration of their chemical behavior as a guide to their potential antimicrobial activity. As an initial approach to the synthesis of the desired 1,3,4-oxadiazol-2(3H)-ones, the starting material, 3-phenylsydnone, was prepared in 2 steps from commercially available N-phenylglycine in good …

Determination Of Atmospheric Particulate Matter Composition In The Dayton Metro Area, Saagar Mahendra Patel

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Quartz filters from high-volume air samplers of particulate matter of a size less than 10 micrometers in diameter (PM₁₀) located in Moraine and Yellow Springs, Ohio, were obtained from the Regional Air Pollution Control Agency and analyzed for levoglucosan, metals, and the EPA 16 priority polycyclic aromatic hydrocarbons (PAHs). Average concentration of levoglucosan increased as ambient temperature decreased. Winter concentrations of levoglucosan for Moraine and Yellow Springs were 39.41 ± 31.58 µg/g and 51.52 ± 27.44 µg/g, respectively, which is due to a greater amount of residential wood burning in the colder months. The concentration of biomass burning …

Poly(Arylene Ether Sulfone)S With Ammonium Groups Located On Pendent Phenyl Sulfonyl Moieties For Anionic Exchange Membranes, Trevor I. Schumacher

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A series of poly(aryl ether sulfone)s with varying percentages of ammonium groups, located on truly pendent positions, was prepared and characterized. The initial polymers were prepared by nucleophilic aromatic substitution (NAS) polycondensation reactions of varying ratios of 3,5-difluoro-4'-methyldiphenylsulfone and 4,4'-difluorodiphenylsulfone, with bisphenol-A as the nucleophilic reaction partner. The tolyl groups in the resulting polymers were subjected to radical bromination with N-bromosuccinimide, followed by amination with three different amines: trimethylamine, dimethylhexadecylamine, and N-methylimidazole. The polymers were characterized by 1H and 13C NMR spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. With the exception of the 100% functionalized polymers, tough films were observed …

Virus Particles Provide Nanotopographical Cues For Osteogenic Differentiation Of Mesenchymal Stem Cells, Kamolrat Metavarayuth

Theses and Dissertations

One key aspect of tissue engineering is to develop biomimetic scaffolding materials that can modulate the proliferation, self-renewal and differentiation of multipotent stem cells into different lineages. Bone marrow derived mesenchymal stem cells (BMSCs) can differentiate into several target cells such as osteoblasts, chondrocytes, adipocytes, and smooth muscle cells. BMSCs are commonly used for in vitro osteogenesis studies in bone tissue engineering field. However the mechanisms and signaling pathways that these cells use to recognize and response to biomaterial surface are still unclear. This dissertation focuses on investigating the effect of chemical and physical cues introduced by virus nanoparticles on …

The Role Of Ferric Oxide Particles As Sources And Sinks Of Reactive Oxygen Species During The Autoxidation Of Ferrous Iron, Shengnan Meng

Theses and Dissertations

The oxic portion of the biosphere is a metastable mixture of different oxidation states of carbon, sulfur and oxygen energetically poised from equilibrium by the net rate differentials between photosynthetic carbon fixation and its metabolic or abiotic oxidation. The direct reaction of dioxygen with reduced carbon or sulfur is spin forbidden and therefore kinetically slow, but ferric and ferrous iron species serve as catalysts for enabling their oxidation and therefore play critical roles in the environment. This thesis reports exploratory and hypothesis driven research that seeks a better understanding of the physical and chemical limitations on the effectiveness of iron …

Characterization Of 1-Deoxy-D-Xylulose 5-Phosphate Reductoisomerase (Dxr) From Vibrio Vulnificus, Nikita K. Ussin

Theses and Dissertations

Vibrio vulnificus, a gram-negative bacterium, is the leading cause of seafood-borne illnesses and mortality in the United States. Previous studies of bacterial pathogens have identified a metabolite essential to V. vulnificus growth and function. 1-deoxy-D-xylulose 5-phosphate reductoisomerase (Dxr) is an essential enzyme in the viability of many bacteria and catalyzes the rearrangement of 1-deoxy-D-xylulose 5-phosphate (Dxp) to 2-C-methylerythritol 4-phosphate (MEP) within the MEP pathway found in plants and bacteria. Previous studies have been conducted to characterize Dxr homologs from other pathogens including E. coli, M. tuberculosis, and P. falciparum. Information on the structural and enzymatic characteristics of Dxr from Vibrio …

The Development Of Bicyclic Peptide Library Scaffolds And The Discovery Of Biostable Ligands Using Mrna Display, David E. Hacker

Theses and Dissertations

Peptides are a promising class of therapeutic candidates due to their high specificity and affinity for cellular protein targets. However, peptides are susceptible to protease degradation and are typically not cell-permeable. In efforts to design more effective peptide drug discovery systems, investigators have discovered that incorporation of non-canonical amino acids (ncAAs) and macrocyclization overcome these limitations, making peptides more drug-like.

In this work, we exploit the promiscuity of wild-type aminoacyl-tRNA synthetases (aaRSs) to ‘mischarge’ ncAAs onto tRNA and ribosomally incorporate them into peptides using a cell-free translation system. We have demonstrated the ability to incorporate five ncAAs into a single …

Vespucci: A Free, Cross-Platform Software Tool For Spectroscopic Data Analysis And Imaging, Daniel Patrick Foose

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Vespucci is a software application developed for imaging and analysis of hyperspectral datasets. Vespucci offers several advantages over other software packages, including a simple user interface, no cost, and less restrictive licensing. Vespucci incorporates several analysis techniques including univariate imaging, principal components analysis, partial-least-squares regression, vertex components analysis and k- means clustering. Additionally, Vespucci can perform a number of useful data-processing operations, including filtering, normalization, baseline correction, and background subtraction. Datasets that consist of spatial or temporal data with a corresponding digital signal, including spectroscopic images, mass spectrometric images, and X-ray diffraction data can be processed in this software. The …