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Cu-Promoted C-H Bond Hydroxylation Inspired By Cu-Dependent Metalloenzymes, Rachel Trammell 2021 Southern Methodist University

Cu-Promoted C-H Bond Hydroxylation Inspired By Cu-Dependent Metalloenzymes, Rachel Trammell

Chemistry Theses and Dissertations

From 2003 to 2015, Schӧnecker and Baran proposed a dinuclear Cu/O2 species in their mechanistic proposal for the hydroxylation of sp3 C-H bonds within their systems (proposed based on yields). Inspired from the site selectivity of this methodology and poor analysis of the mechanism, the first project was inspired to re-examine the sp3 C-H bond hydroxylation by Schrӧnecker and Baran and perform an intensive investigation into understanding how Cu/O2 interact which led us to propose a new mechanism based on the evidence collected (i.e., LCuII-hydroperoxide species that undergoes homolytic O-O bond ...


Initial Investigation Of Wildflower Honey Using Headspace Solid-Phase Microextraction Coupled With Gas Chromatography-Mass Spectrometry For Geographical Information, Tyra Countiss 2021 Coastal Carolina University

Initial Investigation Of Wildflower Honey Using Headspace Solid-Phase Microextraction Coupled With Gas Chromatography-Mass Spectrometry For Geographical Information, Tyra Countiss

Honors Theses

Honey has been used as a food, sugar substitute, and flavor enhancer forever. The uses for honey are extremely varied from food to medicine. It is widely touted that you can address seasonal allergies, especially those following a move, by eating local honey. For this to be true the composition of the local honey, including trapped pollen, would allow allergy symptoms to be eliminated. In this project, the volatile and semi-volatile aroma compounds in wild flower honey from several different locations were analyzed. Headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to help develop the ...


Development Of A Rapid Drug Detection Method For Insects Using Paper Spray Ionization Mass Spectrometry (Psi-Ms), Alexandria Plyler 2021 Duquesne University

Development Of A Rapid Drug Detection Method For Insects Using Paper Spray Ionization Mass Spectrometry (Psi-Ms), Alexandria Plyler

Undergraduate Research and Scholarship Symposium

Insects have the ability to reflect the chemical environment that they have developed in. Thus, necrogenous insects can reflect the chemical environment of cadavers they have fed on. Forensic scientists can potentially utilize insect larvae as an alternate biological matrix to detect drugs in cadavers that are skeletonized, burned, or otherwise badly damaged. Analysis of insects using paper spray ionization mass spectrometry (PSI-MS), an analytical method requiring little to no sample preparation, could prove a rapid, cost-effective, and non-destructive alternative form of toxicological analysis. Traditional tissue analysis via GC and LC-MS often require lengthy sample preparation, use expensive reagents, and ...


Determination Of Metals And Microplastics In Sediment From Oyster Reefs In The Mississippi Sound, Shelby Goza 2021 University of Mississippi

Determination Of Metals And Microplastics In Sediment From Oyster Reefs In The Mississippi Sound, Shelby Goza

Honors Theses

This research centers on the determination of metals (Cd, Pb, V, Cr, Mn, Fe, Co, Ni, Cu) and microplastics (MPs) in marine sediment from oyster reefs in the Mississippi Sound Estuary. Oysters (Crassostrea virginica) are a vital part of the Gulf Coast economy, but their population has dramatically declined in recent years due to multiple stressors, including oil spills and fluctuations in salinity from flooding. Increasingly frequent flooding events also introduce high loads of MPs and sediments containing heavy metals from the Mississippi River. These pollutants can have deleterious effects on oyster biology; however, they have not been adequately studied ...


Effects Of Halogen Bonding On 13c Nmr Shifts Of Various Tolan Species, Anthony Lybrand 2021 University of Mississippi

Effects Of Halogen Bonding On 13c Nmr Shifts Of Various Tolan Species, Anthony Lybrand

Honors Theses

Halogen bonding is slowly becoming a more and more useful part of the world of chemistry and is beginning to be incorporated into various aspects of the chemical industry. This study’s purpose is to determine whether or not halogen bonding can cause any effect in the 13C NMR shifts. The specific purpose of this study is to determine whether these chemical shifts change when a Lewis Base is added to the dissolved sample. In order to do this, the tolan species (4-iodotolan and 4-chlorotolan) had to be synthesized. Once synthesized, the tolan species were analyzed via NMR. NMR data ...


Theranostic Nanoparticles Folic Acid-Carbon Dots-Drug(S) For Cancer, Godwin Kweku Babanyinah 2021 East Tennessee State University

Theranostic Nanoparticles Folic Acid-Carbon Dots-Drug(S) For Cancer, Godwin Kweku Babanyinah

Electronic Theses and Dissertations

This study aims to prepare theranostic nanoparticles (NPs) that are expected to increase cancer diagnostics and therapeutic efficacy. We prepared the NPs constituting carbon dots (CDs) as an imaging agent, folic acid as a targeting agent, doxorubicin (DOX), or gemcitabine (GEM) as chemotherapy agents. The NPs include noncovalent FA-CDs-DOX, covalent CDs-FA-DOX, and covalent FA-CDs-GEM. Through ultraviolet-visible spectroscopy, fluorescence spectroscopy, and Fourier transform-infrared spectroscopy, the fabrication of these NPs was confirmed. It was discovered that the high drug loading efficiency is the noncovalent series while the high drug loading capacity is the covalent series The in-vitro pH-dependent drug release data indicate ...


Electrodeposition Of Hydrogen Molybdenum Tungsten Bronze Films And Electrochemical Reduction Of Carbon Dioxide., Mohammad Bajunaid 2021 East Tennessee State University

Electrodeposition Of Hydrogen Molybdenum Tungsten Bronze Films And Electrochemical Reduction Of Carbon Dioxide., Mohammad Bajunaid

Electronic Theses and Dissertations

The foremost aim for performing this study was to focus on the electrodeposition of mixed hydrogen molybdenum tungsten bronze films, which have the potential for e transfer interactions carrying out the reduction of carbon dioxide. A yellow peroxymolybdic tungstate solution was prepared and used for the electrodeposition of hydrogen molybdenum tungsten bronze films on conductive carbon paper. Electrodeposition was carried out at -2.0 V from 20 - 120 minutes to determine the effect of deposition time on film thickness and CO2 reduction. These films were characterized by X-ray photoelectron spectroscopy. The deposited films served as a working electrode for ...


Lc-Ms/Ms Method Development And Analysis Of Tricyclic Antidepressants In Human Plasma, Shahbaz Gul 2021 University of Mississippi

Lc-Ms/Ms Method Development And Analysis Of Tricyclic Antidepressants In Human Plasma, Shahbaz Gul

Honors Theses

Depression has become one of the most prominent problems in society, disrupting both personal and social lives. Tricyclic antidepressants (TCAs) were first developed in the 1950’s and became some of the leading anti-depressant medications on the market later that decade. Today, newer anti-depressants have risen to the forefront, being safer and having a lower side-effect probability. Nonetheless, TCAs continue to be prescribed for severe depression, especially in cases where the newer anti-depressants have failed. However, TCAs are still highly potent, the toxicity associated with these compounds cannot be ignored. They have considerable cardiovascular and neurological toxicity, and in the ...


Determination Of Metals In Whey And Vegan Protein Supplements Using Inductively Coupled Plasma Mass Spectrometry, Megan Lofaso 2021 University of Mississippi

Determination Of Metals In Whey And Vegan Protein Supplements Using Inductively Coupled Plasma Mass Spectrometry, Megan Lofaso

Honors Theses

Driven by a demand for health and wellness products worldwide, the dietary supplement industry continues to expand with an economic impact >$100 billion in the USA alone. However, the industry is plagued by a lack of regulation and incidents of contamination, including with toxic heavy metals that can put consumers at potential risk. In this study, eight trace elements (Cd, Pb, Fe, Co, Mn, V, Cu, and Cr), including heavy metals (Cd and Pb), were determined in whey and vegan protein powder by inductively coupled plasma mass spectrometry (ICP-MS) after microwave-assisted digestion using nitric acid and hydrogen peroxide. Samples were ...


Experimental And Theoretical Investigation Of Regioselectivity For A Series Of Ketoimines With Nuclear Magnetic Resonance Spectroscopy And Density Functional Theory, Amanda Stahl, Joseph M. Fritsch, Kelsey R. Brereton 2021 Pepperdine University

Experimental And Theoretical Investigation Of Regioselectivity For A Series Of Ketoimines With Nuclear Magnetic Resonance Spectroscopy And Density Functional Theory, Amanda Stahl, Joseph M. Fritsch, Kelsey R. Brereton

Seaver College Research And Scholarly Achievement Symposium

A series of ketoimines bearing pendant quinolyl substituents were prepared by Schiff base condensation of 1,3-diketones with two different substituents: trifluoromethyl and an alkyl/aryl group (e.g., Me, Et, iPr,tBu, Ph. Synthetic reactions of ketoimines with varying alkyl/aryl substituents altered the distribution of regioisomers as measured in isolated yields and detected by 1H and 19F NMR spectroscopy of crude reaction mixtures. Reaction with the least sterically encumbered diketone (CF3with Me) resulted in mixture of ketoimines with virtually quantitative formation of the ketoimine resulting from quinolyl addition to the carbonyl adjacent ...


Nitro Group Reduction For Use In Organic, Cathodic Materials, Brock G. Goeden 2021 University of South Dakota

Nitro Group Reduction For Use In Organic, Cathodic Materials, Brock G. Goeden

Honors Thesis

The industrial demand for higher capacity, light-weight battery materials has skyrocketed in recent years due to heavy investments in portable electronics, electronic vehicles, and renewable energy sources. However, rechargeable battery technology has seen little improvement since the invention of the Lithium-Ion battery in the 1980s. The low energy density of the traditionally utilized LiCoO2 cathodic material (specific capacity: 272 mAh g-1), has limited its potential to meet these increasing demands. To solve this problem, our research group is investigating new types of lightweight, organic, polymeric materials with conductive backbones as a possible replacement for the cathodic materials in Lithium-Ion batteries ...


Carrier-Free Chemo-Ptt/Pdt Ionic Nanomaterials For Combination Cancer Therapy, Samantha Macchi 2021 Ouachita Baptist University

Carrier-Free Chemo-Ptt/Pdt Ionic Nanomaterials For Combination Cancer Therapy, Samantha Macchi

Arkansas Women in STEM Conference

Herein, we describe a carrier-free combination nanodrug for treatment of cancer. In this work, we combined a photothermal compound and a chemotherapeutic drug using ionic liquid chemistry. We utilized a facile, one-step metathesis approach to replace the counter cation of a near infra-red (NIR) dye (photothermal agent) with a chemotherapeutic cation to synthesize an ionic material-based combination cancer therapy drug to deliver multiple mechanisms simultaneously. The nanodrugs were developed by using a reprecipitation method. The detailed photophysical properties of this new combination therapy molecule was investigated in ethanol solution as well as in nanoparticles forms in aqueous media. The singlet ...


Three-Way Analysis-Based Ph-Uv-Vis Spectroscopy For Quantifying Allura Red In An Energy Drink And Determining Colorant's Pka, Erdal Dinç Prof., Nazangül Ünal, Zehra Ceren Ertekin 2021 Ankara University

Three-Way Analysis-Based Ph-Uv-Vis Spectroscopy For Quantifying Allura Red In An Energy Drink And Determining Colorant's Pka, Erdal Dinç Prof., Nazangül Ünal, Zehra Ceren Ertekin

Journal of Food and Drug Analysis

Three-way analysis-based pH-UV-Vis spectroscopy was proposed for quantifying allura red in an energy drink product without the need for chromatographic analysis, and determining the colorant’s pKa without using any titration technique. In this study, UV-Vis spectroscopic data matrices were obtained from absorbance measurements at five different pH levels from pH 8 to pH 12 and arranged as a three-way array (wavelength x sample x pH). In the three-way analysis procedure, parallel factor analysis (PARAFAC) was implemented to decompose the three-way array into a set of trilinear components. Each set of three components relates to spectral, pH and relative concentration ...


Nsf Career Award Supports Schwartz's Research On The Chemical Process For Making Rubber Component, Marcus Wolf 2021 Division of Marketing and Communications

Nsf Career Award Supports Schwartz's Research On The Chemical Process For Making Rubber Component, Marcus Wolf

General University of Maine Publications

advance his ongoing dissection of the Lebedev process. The well-known, multi-step chemical reaction is used to make butadiene from biomass-derived ethanol. However, little research has been conducted on the Lebedev process at the molecular level. Understanding the intricacies of this process will help researchers create new catalysts necessary for the chemical reactions to make goods from both petroleum and biomass, that would increase butadiene yield.


Galvanic Corrosion Of Carbon Steel Coupled To Copper In Used Nuclear Fuel Containers, Lindsay J. Braithwaite 2021 The University of Western Ontario

Galvanic Corrosion Of Carbon Steel Coupled To Copper In Used Nuclear Fuel Containers, Lindsay J. Braithwaite

Electronic Thesis and Dissertation Repository

Deep geological containment of used nuclear fuel will rely on multiple engineered and natural barriers, two of which are the copper-coated used fuel containers and the compacted bentonite clay buffer boxes in which the containers will rest. This work focused on possible galvanic interactions between the copper coating and the steel substrate of the container, which may occur at a hypothetical through-coating defect. In the presence of various amounts of chloride, bentonite, and oxygen, corrosion of the copper/carbon steel couple was studied using electrochemical tests complemented by surface characterization and 3D X-ray imaging. We investigated the effects of copper-to-steel ...


Oxygen Binding Thermodynamics Of Human Hemoglobin In The Red Blood Cell, Kyle K. Hill 2021 University of Nebraska-Lincoln

Oxygen Binding Thermodynamics Of Human Hemoglobin In The Red Blood Cell, Kyle K. Hill

Student Research Projects, Dissertations, and Theses - Chemistry Department

We report for the first time the binding constants and Hill numbers for oxygen in the red blood cell under physiological conditions. When compared to our results for hemoglobin in solution, our results show conclusively that hemoglobin binds oxygen more tightly and with lower co-operativity when packed in the red blood cell. At 18°C, these differences are striking: the respective half-saturation values are 15.57 µM (in red blood cells) and 18.83 µM (in solution), with corresponding Hill numbers of 2.475 (in red blood cells) and 2.949 (in solution). The optical complications that arise from high ...


Sulfur Anions: Comments Upon Structure, Charles A. Kingsbury 2021 University of Nebraska-Lincoln

Sulfur Anions: Comments Upon Structure, Charles A. Kingsbury

Faculty Publications -- Chemistry Department

This work emphasizes the need for solvent simulation as well as a counterion in calculations concerning anions, although optimization may be difficult. Solvent and counterion both play a large role in conformation of the ion. Part of the reason for the success of sulfur anions in chemical reactions may be the ability of sulfone oxygen(s) to coordinate with the counterion (usually lithium). The “solvent” partially dissociates lithium from the carbanion center.


High-Pressure Studies Of Flexible Metal-Organic Frameworks And Their Performance For Co2 Adsorption Using Infrared Spectroscopy, Boqing Li 2021 The University of Western Ontario

High-Pressure Studies Of Flexible Metal-Organic Frameworks And Their Performance For Co2 Adsorption Using Infrared Spectroscopy, Boqing Li

Electronic Thesis and Dissertation Repository

Metal-organic frameworks (MOFs) are crystalline porous materials comprising metal ions/clusters and organic linkers. MOFs feature very large surface area and broad tunability, which distinguish them from traditional CO2 adsorbents. High external pressure can significantly modify the framework structures and CO2 adsorption properties of MOFs. MIL-53(Al) and NH2-MIL-53(Al) exhibit excellent CO2 affinity by forming hydrogen bonds between bridging OH groups and adsorbed CO2. We used in situ infrared spectroscopy to investigate the high-pressure performance of their framework structures and CO2 adsorption capacities. Diamond anvil cell was employed to apply high pressures ...


Investigating The Corrosion Behaviour Of Ni-Based Alloys In Industrially Relevant Environments, Jeffrey D. Henderson 2021 The University of Western Ontario

Investigating The Corrosion Behaviour Of Ni-Based Alloys In Industrially Relevant Environments, Jeffrey D. Henderson

Electronic Thesis and Dissertation Repository

Typical engineering materials may experience high corrosion rates when exposed to aggressive service conditions. Such conditions include high concentrations of aggressive anions and oxidants, high solution acidity, and/or high temperatures. Alloys with high corrosion resistance may be selected to avoid material failure caused by corrosion, for example, Ni-Cr-Mo alloys. These alloys exhibit excellent corrosion resistance due to the formation of a passive oxide film, primarily containing Cr and Mo. However, film breakdown can result in localized corrosion, e.g., crevice corrosion. Localized corrosion processes can penetrate deep into the bulk alloy, threatening its integrity. While the oxide film and ...


Otolith Microchemistry Reveals Low Habitat Connectivity Of California Killifish (Fundulus Parvipinnis) Across A Range Of Spatial Scales, Lisa Robison 2021 University of San Diego

Otolith Microchemistry Reveals Low Habitat Connectivity Of California Killifish (Fundulus Parvipinnis) Across A Range Of Spatial Scales, Lisa Robison

Theses

As wetlands face continued fragmentation worldwide, an understanding of habitat connectivity and how fishes that rely on these environments is imperative to conduct effective marine management. Site fidelity and habitat connectivity are vital measures of the interdependence of fish populations living in neighboring marshes (or in regions of a single marsh).

Here, we examine the habitat connectivity, site fidelity, and movement of California killifish (Fundulus parvipinnis) within and among three estuaries in Southern California through otolith microelemental analysis. Assessing the site fidelity of estuarine fishes is important to determine the level of connectivity between spatially distinct populations within a bay ...


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