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Electrodeposition Of Hydrogen Molybdenum Bronze Films And Electrochemical Reduction Of Carbon Dioxide At Low Over Potentials, Sami Alharbi 2019 East Tennessee State University

Electrodeposition Of Hydrogen Molybdenum Bronze Films And Electrochemical Reduction Of Carbon Dioxide At Low Over Potentials, Sami Alharbi

Electronic Theses and Dissertations

Hydrogen molybdenum oxide, known has molybdenum bronze, is a material of interest due to catalyzing electron transfer reactions. Specifically, molybdenum bronze is an electrocatalyst toward carbon dioxide reduction. Electrochemical deposition from a peroxymolybdic acid solution is a method for preparing molybdenum bronze films. This work demonstrates reproducible electrodeposition on indium tin oxide substrates and conductive carbon paper. Film thickness depends on concentration, time and pH. After characterization by film thickness, resistance, XRD and XPS, the as deposited films served as the working electrode for electrochemical reduction of carbon dioxide in 0.1 M NaHCO3. Ion chromatography determined formate resulting ...


Synthesis, Stabilization, And Modification Of Zinc Oxide Nanoparticles For Biological Applications, Allison Kimberly Freese 2019 Missouri State University

Synthesis, Stabilization, And Modification Of Zinc Oxide Nanoparticles For Biological Applications, Allison Kimberly Freese

MSU Graduate Theses

Nanoparticles have become very useful as delivery systems in biomedicine. The nanoparticles can be layered with different compounds to produce a vessel for transport of biological materials. Specifically, gold nanoparticles layered with a reducing agent, lysozyme, and polyelectrolytes can be synthesized to transport lysozyme into a cell. However, zinc oxide nanoparticles are cheaper, biocompatible nanoparticles that can be used for the same process. Here in, zinc oxide nanoparticle conjugates were synthesized, modified, and analyzed to be used as a biological material delivery system. The zinc oxide nanoparticles were synthesized using zinc chloride and sodium hydroxide. The particles were then layered ...


Development Of Bismuth Oxyhalide Photocatalysts For Environmental And Industrial Applications, Robert Arthur 2019 University of Maine

Development Of Bismuth Oxyhalide Photocatalysts For Environmental And Industrial Applications, Robert Arthur

Electronic Theses and Dissertations

Heterogeneous semiconductor photocatalysis, of interest for water splitting and environmental remediation applications, uses light to drive reactions. Metal oxide and sulfide semiconductors have been previously studied but have limitations that include large band gap energies and high rates of recombination. Bismuth oxyhalides (BiOX) are an emerging class of photocatalysts with tunable band gaps and low rates of recombination due to their unique crystal structures. Studies of BiOX photocatalytic activity have largely focused on removal of azo dyes from aqueous solutions, with little attention paid to degradation byproducts. Furthermore, these catalysts have not been explored as a means to conduct organic ...


Subcellular-Level Resolution Maldi-Ms Imaging Of Maize Leaf Metabolites By Maldi-Linear Ion Trap-Orbitrap Mass Spectrometer, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee 2019 Iowa State University

Subcellular-Level Resolution Maldi-Ms Imaging Of Maize Leaf Metabolites By Maldi-Linear Ion Trap-Orbitrap Mass Spectrometer, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee

Marna Yandeau-Nelson

A significant limiting factor in achieving high spatial resolution for matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) imaging is the size of the laser spot at the sample surface. Here, we present modifications to the beam-delivery optics of a commercial MALDI-linear ion trap-Orbitrap instrument, incorporating an external Nd:YAG laser, beam-shaping optics, and an aspheric focusing lens, to reduce the minimum laser spot size from ~50 μm for the commercial configuration down to ~9 μm for the modified configuration. This improved system was applied for MALDI-MS imaging of cross sections of juvenile maize leaves at 5-μm spatial resolution using an oversampling ...


Decrypting Female Attractivity In Garter Snakes, Holly Rucker 2019 James Madison University

Decrypting Female Attractivity In Garter Snakes, Holly Rucker

Senior Honors Projects, 2010-current

Pheromones are utilized by many species as sexual signals driving mate choice, and pheromone production in vertebrates hinges on sex hormone action. Female red-sided garter snakes (Thamnophis sirtalis parietalis) produce a skin-based sex pheromone used by males for mate detection and selection. Estradiol is necessary for pheromone production, yet the specific mechanisms within the skin are unknown. Central to this is the metabolism of testosterone to estradiol via the enzyme aromatase. It is hypothesized that female garter snakes synthesize estradiol locally in the skin and maintain pheromone production via tissue-specific regulation of aromatase. Further, I hypothesize that female attractiveness, and ...


Anthocyanin Stability In Food Products Made With Freeze-Dried Blueberry Powder, Samantha Findley 2019 University of Arkansas, Fayetteville

Anthocyanin Stability In Food Products Made With Freeze-Dried Blueberry Powder, Samantha Findley

Food Science Undergraduate Honors Theses

This study evaluated the stability of anthocyanins in six blueberry products (gummy, graham bar, oatmeal bar, rice krispy bar, ice pop and juice) prepared with freeze-dried wild blueberry powder during processing and over eight weeks storage. Total anthocyanins were determined by HPLC before processing and at day 0 and 2, 4, 6, and 8 weeks of storage. Thermal processing of gummy and graham bar products resulted in significant losses of anthocyanins (50% and 31%, respectively). An eight-week storage time also resulted in a significant decrease in anthocyanins (7% to 51%) in products stored at ambient temperature. The ice pop, which ...


Gas Chromatography Analysis Of Co2 Reduction Photocatalysis With Zinc Dipyrrin Complexes, Alex Day 2019 East Tennessee State University

Gas Chromatography Analysis Of Co2 Reduction Photocatalysis With Zinc Dipyrrin Complexes, Alex Day

Undergraduate Honors Theses

Bis(1,3,7,9-tetramethyl-5-mesityldipyrrinato)zinc(II) (ZnDPY) was synthesized in the lab by the McCusker group and a procedure was created to analyze its ability as a photosensitizer, a molecule that provides the energy for the reaction to occur by capturing light energy and turning it into a form that can be used by the photocatalyst. While more work is needed, preliminary steps have been made to create a process that can analyze the amount of carbon monoxide produced by a photocatalytic CO2 reduction reaction with ZnDPY as the photosensitizer. Progress has been made via the setup of ...


Development Of Granulated Adsorbent For Clean-Up Of Water Contaminated By Cesium, Esther Alorkpa 2019 East Tennessee State University

Development Of Granulated Adsorbent For Clean-Up Of Water Contaminated By Cesium, Esther Alorkpa

Electronic Theses and Dissertations

A study was conducted on sol-gel synthesis of an adsorbent (phosphotungstic acid embedded in silica gel, H-PTA/SiO­2) of radioactive cesium. A novelty of this work is covalent bonding of PTA to the surface of solid support that prevents leaching from the surface of the material. The sample was granulated with a binder, aluminium oxide (γ-Al2O3). Solid-state NMR and FT-IR spectroscopy were used to confirm the presence of Keggin units of PTA in the bound materials. Thermal analysis of H-PTA/SiO­2 - γ-Al2O3 (50 %) showed that the water content in the bound material ...


A Raman Spectroscopic Investigation Of Neurotransmitters And Photon Migration, Ian C. Bennie 2019 University of Tennessee, Knoxville

A Raman Spectroscopic Investigation Of Neurotransmitters And Photon Migration, Ian C. Bennie

Chancellor’s Honors Program Projects

No abstract provided.


Neurological Disease Detection Using Surface Enhanced Spatially Offset Raman Spectroscopy (Sesors), Taylor D. Payne 2019 University of Tennessee- Knoxville

Neurological Disease Detection Using Surface Enhanced Spatially Offset Raman Spectroscopy (Sesors), Taylor D. Payne

Chancellor’s Honors Program Projects

No abstract provided.


Elemental Analysis Of Edible Clay From The Copperbelt Province Of Zambia, Amelia M. Craze, Mina L. Brandon 2019 University of Mississippi

Elemental Analysis Of Edible Clay From The Copperbelt Province Of Zambia, Amelia M. Craze, Mina L. Brandon

The University of Mississippi Undergraduate Research Journal

Trace elements in three edible clay samples from an open-air market in Kitwe, Zambia were analyzed for heavy metals using a scanning electron microscope coupled with an energy-dispersive spectrometer. The ingestion of clays has been observed throughout history but persists in many rural countries that lack sufficient access to proper medical care. In many African countries, women have been observed eating clay during pregnancy to reduce nausea or meet their recommended intake of iron. Similar studies identified harmful heavy metals in the makeup of the edible clays, however, the results of this analysis elemental analysis coupled with the SEM for ...


Preparation And Characterization Of Ruthenium-Gold Raman-Active Catalytic Surfaces, Thang Nguyen 2019 Chapman University

Preparation And Characterization Of Ruthenium-Gold Raman-Active Catalytic Surfaces, Thang Nguyen

Student Scholar Symposium Abstracts and Posters

Heterogeneous reactions at the gas-solid interface play a major role in many important industrial and environmental processes. These reactions typically rely on metal surfaces, to act as a catalyst between gas phase reactants and products. The catalysts lower the transition state barrier in the formation of the products. The mechanisms of reactions on catalysts is often not fully known due to the difficulty of observing the bond breakage and formation between gaseous molecules at the interface. One method in which the catalytic mechanism can be studied is by using Raman Spectroscopy. However, one drawback of this method is the fact ...


Nanopore Sensing For Single-Molecule Glycomics, Melissa Morris 2019 University of Rhode Island

Nanopore Sensing For Single-Molecule Glycomics, Melissa Morris

Senior Honors Projects

Single-molecule sensing represents the ultimate in chemical sensitivity, but is tremendously challenging to achieve. Larger proteins have a diameter of 10 nm, which is 1/10,000th the size of a strand of hair, and 1/100,000th the size of a grain of sand. Because imaging at the nanoscale is difficult and expensive, developing techniques to measure single molecules requires ingenuity, and often relies on the interpretation of electrical signals. So how do nanopores help us measure at the single-molecule level?

A nanopore is simply a nano-sized hole in a membrane or material. In the early stages ...


Use Of Anodic Stripping Voltammetry To Study The Size-Selective Electrophoretic Deposition And Aggregation-Dependent Oxidation Of Metal Nanoparticles., Stacy L. Allen 2019 University of Louisville

Use Of Anodic Stripping Voltammetry To Study The Size-Selective Electrophoretic Deposition And Aggregation-Dependent Oxidation Of Metal Nanoparticles., Stacy L. Allen

Electronic Theses and Dissertations

This dissertation describes how anodic stripping voltammetry (ASV) was used to study size-controlled electrophoretic deposition (EPD) and the aggregation-dependent oxidation properties of citrate-stabilized Au nanoparticles (NPs). EPD of citrate-coated Au NPs occurs in the presence of hydroquinone (HQ) onto indium-tin-oxide-coated glass electrodes (glass/ITO) at potentials positive of the HQ oxidation potential. HQ oxidation produces protons at the electrode surface, which serve to neutralize the citrate molecules that electrostatically stabilize the Au NPs. Neutralization leads to the loss of stabilization and deposition onto the electrode. EPD in the presence of ferrocyanide, a non-proton-producing molecule, at oxidation potentials resulted in no ...


Heavy Metal Detection With Bismuth Film Electrode, Jen Olivero, Iain Laprade, Gabby Servito 2019 The University of San Francisco

Heavy Metal Detection With Bismuth Film Electrode, Jen Olivero, Iain Laprade, Gabby Servito

Creative Activity and Research Day - CARD

The purpose of this project is to extend the application of stripping square-wave voltammetry to allow for the detection of various heavy metals in water samples, to include lead, cadmium, and zinc contaminants. Glassy carbon bismuth film electrodes proved to be more reliable than screen printed carbon electrodes for detection of heavy metals. Parameters were optimized to allow for the quantification of lead, zinc, and cadmium simultaneously in tap water along with an unknown Fromm water sample. Cadmium and thallium were found to be present at the same potential on the voltammogram; this prevented simultaneous detection of both metals. Bismuth ...


Effect Of Salt Concentration On Electrochemical Detection Of Dna, Ziming Dong, Eddie Madrigal, Ryan West Dr. 2019 University of San Francisco

Effect Of Salt Concentration On Electrochemical Detection Of Dna, Ziming Dong, Eddie Madrigal, Ryan West Dr.

Creative Activity and Research Day - CARD

Electrochemical approaches for biological sensing offer the potential advantages of facile sample preparation, fast response times, ease of parallel and multiplexed measurements, and the possibility of miniaturization (of sample sizes, electrodes, and associated electronics). All of these factors contribute towards the feasibility of electrochemical methods in biological sensing and analysis. This potential has already been achieved with the commercialization of blood glucose meters, which often rely on an electrochemical transduction mechanism. We have previously demonstrated the ability to electrochemically detect and differentiate complementary and mismatched DNA using our method of melting DNA duplexes at electrified gold surfaces, i.e. e-melting ...


The Effects Of Ph On The Kinetics Of The Follow-Up Reaction Of Dopamine O-Quinone, Cyril Fong, Ziming Dong 2019 University of San Francisco

The Effects Of Ph On The Kinetics Of The Follow-Up Reaction Of Dopamine O-Quinone, Cyril Fong, Ziming Dong

Creative Activity and Research Day - CARD

The electrochemical studies of dopamine have been conducted for many years due to dopamine’s importance as a neurotransmitter and its function in daily life for individuals. Dopamine undergoes electrochemical redox reactions in which the different products can be detected by cyclic voltammetry.3 The focus of the experiments was to determine the pH range at which dopamine o-quinone would undergo cyclization as well as the relationship between the rate of cyclization as pH in the physiological range. The measurements were taken using a gold working electrode vs. a Ag/AgCl (1 M KCl) reference electrode. It was observed that ...


Modeling Solid-Phase Microextraction Of Volatile Organic Compounds By Porous Coatings Using Finite Element Analysis, Bulat Kenessov, Miras Derbissalin, Jacek A. Koziel, Dmitry S. Kosyakov 2019 Al-Farabi Kazakh National University

Modeling Solid-Phase Microextraction Of Volatile Organic Compounds By Porous Coatings Using Finite Element Analysis, Bulat Kenessov, Miras Derbissalin, Jacek A. Koziel, Dmitry S. Kosyakov

Agricultural and Biosystems Engineering Publications

Experimental optimization of analytical methods based on solid-phase microextraction (SPME) is a complex and labor-intensive process associated with uncertainties. Using theoretical basics of SPME and finite element analysis software for the optimization proved to be an efficient alternative. In this study, an improved finite element analysis-based model for SPME of volatile organic compounds (VOCs) by porous coatings was developed mainly focussing on the mass transport in coatings. Benzene and the Carboxen/polydimethylsiloxane (Car/PDMS) coating were used as the model VOC and a porous SPME coating, respectively. It has been established that in the coating, volumetric fractions of Carboxen, PDMS ...


Quantitative Analysis Of Iron In Beer Using Cloud Point Extraction, Joshua Rempfer 2019 University of Lynchburg

Quantitative Analysis Of Iron In Beer Using Cloud Point Extraction, Joshua Rempfer

Student Scholar Showcase

Determination of Iron concentration in Apocalypse Ale beer using a preconcentration method coupled with UV-Vis spectroscopy. Samples will be cross checked with MP-AES to ensure precise and accurate results.


Elemental Analysis Of Legacy Sediments At College Lake, Amelia Dalton 2019 University of Lynchburg

Elemental Analysis Of Legacy Sediments At College Lake, Amelia Dalton

Student Scholar Showcase

College Lake is a large reservoir located on the campus of the University of Lynchburg. College Lake’s ecosystem has degraded over the years due to the buildup of sediment, nutrients, and raw sewage. Increased urbanization in the area has also most likely contributed to the contaminants present within the system. Because of flooding issues during the summer of 2018, Lynchburg CIty officials drained College Lake, which caused sediment to be released downstream. To better understand the transport of heavy metals in the sediments released from College Lake, sediment core samples were taken from College Lake, Hollins Mill Park, and ...


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