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Comparison Of The Vibrational Modes Of Thiolated Gold Nanoparticles Undergoing Core-Conversions Via Raman Spectroscopy, William Gregory Cannella Jr. 2020 University of Mississippi

Comparison Of The Vibrational Modes Of Thiolated Gold Nanoparticles Undergoing Core-Conversions Via Raman Spectroscopy, William Gregory Cannella Jr.

Honors Theses

In this project, the vibrational characteristics/vibrational modes are explored via Raman Spectroscopy for thiolated-gold nanoparticles. This class of compounds is also known as gold nanoparticles (AuNPs). They remain of great interest in research areas such as catalysis, gold dependent nanoelectronics, drug delivery, and sensing, due to their unique size-dependent optical, chiroptical, and electronic properties. Vibrational spectroscopy of thiolated gold nanoparticles are oftentimes considered nontrivial as the compounds strongly absorb light in the visible region of the electromagnetic spectrum, are generally considered weak scatterers, and give off large amounts of fluorescence. This combined with their black appearance, susceptibility to localized ...


Intrinsic Buffer Hydroxyl Radical Dosimetry For Hydroxyl Radical Protein Footprinting, Addison Roush 2020 University of Mississippi

Intrinsic Buffer Hydroxyl Radical Dosimetry For Hydroxyl Radical Protein Footprinting, Addison Roush

Honors Theses

Hydroxyl radical protein footprinting (HRPF) coupled to mass spectrometry is a powerful technique for the analysis of protein topography as it generates covalent mass labels that can survive downstream sample handling, and it is sensitive to the solvent accessibility of amino acid sidechains. Of the multiple platforms for HRPF, fast photochemical oxidation of proteins (FPOP) utilizes a pulsed 248 nm KrF excimer laser to label proteins by photolyzing hydrogen peroxide. FPOP is the most widely used HRPF platform because it labels proteins faster than unfolding can occur. Variations in FPOP sample conditions make it difficult to compare results between experiments ...


The Synthesis Of A Mepeg-Based Hydroxide Conducting Electrolyte And The Optimization Of The Mepeg-Tosylation Reaction, Andrew Ladner 2020 University of Mississippi

The Synthesis Of A Mepeg-Based Hydroxide Conducting Electrolyte And The Optimization Of The Mepeg-Tosylation Reaction, Andrew Ladner

Honors Theses

As society is becoming increasingly aware of the effects of climate change and the ever-looming threat of a fuel shortage, exploring green and renewable alternative energy production, such as fuel cells, is paramount. This project investigates the synthesis of a polyethylene glycol monomethyl ether (MePEGn) based polymer as well as the optimization of the MePEG Tosylation reaction. The MePEG explored contains seven polymerized ethoxy groups (MePEG7). The MePEG7 polymer was modified by substituting a positively-charged trimethylamine group in the place of the alcohol functional group at the end of the PEG chain. The reason for this substitution ...


Investigation Of The History Of Fingerprinting, Advancements In The Field, And Development Of Potential Methods That Could Improve The Detection Of Endogenous And Exogenous Drugs In Latent Prints, Kristen Malloy 2020 University of Mississippi

Investigation Of The History Of Fingerprinting, Advancements In The Field, And Development Of Potential Methods That Could Improve The Detection Of Endogenous And Exogenous Drugs In Latent Prints, Kristen Malloy

Honors Theses

When someone thinks of fingerprinting, they are most likely going to picture how a latent print is matched to the fingerprint of a suspect based on ridge pattern analysis. However, there is much more information that can be obtained from a latent print. The work performed in this thesis focuses the detection of exogenous and endogenous drugs in latent prints. The experiments performed analyzed fingerprints from volunteers that were contaminated with one of three common painkillers: acetaminophen, acetylsalicylic acid (ASA), and ibuprofen. Three different instruments were tested for this purpose: MALDI-MS, ATR-FTIR, and LC-MS. Based on the results gathered, it ...


Phenolic Phytochemicals And Their Antioxidant Activities In Maine-Grown Asian, American-Hybrid, And European Plums, Hye Weon Hwang 2020 University of Maine

Phenolic Phytochemicals And Their Antioxidant Activities In Maine-Grown Asian, American-Hybrid, And European Plums, Hye Weon Hwang

Electronic Theses and Dissertations

Plum fruits of 16 plum cultivars derived from three species, Asian, American-hybrid, and European plums, and one cultivar of an interspecific hybrid between Asian plum and apricot were investigated to identify and quantify two major groups of phenolic phytochemicals, anthocyanins and hydroxycinnamic acids (HCAs) by HPLC–DAD/MS. The plums were harvested from 2014 to 2017. Some cultivars were analyzed through consecutive years to determine year-to-year differences and to evaluate the maturity impacts on the concentration of anthocyanins and HCAs from the partial-ripe stage and tree-ripe stage. Anthocyanins were present in red−purple colored plums, but their profiles varied among ...


Using Tandem Mass Spectrometry And Irmpd Spectroscopy To Determine The Intrinsic Reactions Of Uranyl-Containing Ions, Irena Tatosian 2020 Duquesne University

Using Tandem Mass Spectrometry And Irmpd Spectroscopy To Determine The Intrinsic Reactions Of Uranyl-Containing Ions, Irena Tatosian

Electronic Theses and Dissertations

Developing a comprehensive understanding of the intrinsic reactivity of uranium-containing species remains an important goal, as it may influence future developments in areas ranging from new approaches to nuclear fuel processing to studies of the migration and fate of the element in the environment. At a more fundamental level, such studies contribute to the understanding of the role that 5-f electrons may play in chemical bonding, the so called “f-electron challenge”. Electrospray ionization (ESI) is an effective way to generate gas-phase complexes containing uranium and uranyl ions for subsequent studies of intrinsic structure and reactivity. Studies in the gas-phase are ...


N-Terminal Imine Derivatization For Enhanced De Novo Peptide Sequencing: A Study Of The Fragmentation Pattern Generated From Cid Of Peptide-Imines, Khiry L. Patterson 2020 Duquesne University

N-Terminal Imine Derivatization For Enhanced De Novo Peptide Sequencing: A Study Of The Fragmentation Pattern Generated From Cid Of Peptide-Imines, Khiry L. Patterson

Electronic Theses and Dissertations

In this work, the fragmentation pattern derived from model peptides derivatized to create N-terminal imines (Schiff bases) were evaluated. Collision-induced dissociation of the protonated peptide-imines ([M+H]+) generally produced complete series of the sequence informative an and bn ions, now undoubtedly characteristic of the peptide ion species. A novel product ion was also observed, denoted the yǂ ion, determined by IRMPD spectroscopy and density functional theory to be generated from the elimination of the N-terminal amino acid residue despite the N-terminal modification. It was concluded the pathway involved a nucleophilic attack by an amide nitrogen and the ...


Magnetic Ionic Liquids As Solvents For Rna Extraction And Preservation, Chenghui Zhu, Marcelino Varona, Jared L. Anderson 2020 Iowa State University

Magnetic Ionic Liquids As Solvents For Rna Extraction And Preservation, Chenghui Zhu, Marcelino Varona, Jared L. Anderson

Chemistry Publications

Ribonucleic acid (RNA) is particularly sensitive to enzymatic degradation by endonucleases prior to sample analysis. In-field preservation has been a challenge for RNA sample preparation. Very recently, hydrophobic magnetic ionic liquids (MIL) have shown significant promise in the area of RNA extraction. In this study, MILs were synthesized and employed as solvents for the extraction and preservation of RNA in aqueous solution. RNA samples obtained from yeast cells were extracted and preserved by the trihexyl(tetradecyl) phosphonium tris(hexafluoroacetylaceto)cobaltate(II) ([P66614+][Co(hfacac)3–]) and trihexyl(tetradecyl) phosphonium tris(phenyltrifluoroacetylaceto)cobaltate(II) ([P66614+][Co(Phtfacac)3–]) MIL with a ...


Chemical Transformation Of Biomass Burning Organic Aerosols Due To Photolytic Aging, Hongmin Yu 2020 William & Mary

Chemical Transformation Of Biomass Burning Organic Aerosols Due To Photolytic Aging, Hongmin Yu

Undergraduate Honors Theses

Biomass burning organic aerosol (BBOA), organic aerosol that derived from burning of biomass fuels, has been a major research focus because of its special role in the global budget of atmospheric chemistry and radiative forcing. Due to its chemical complexity, there are gaps in our knowledge about the chemical aging processes of BBOA in the atmosphere. Since many photochemical aging experiments on BBOA are usually conducted for only a few hours, less is known about the photo-aging pathways of the system over an extended timescale. This study presents the analyses of three BBOA filter samples derived from three types of ...


Adaptation Of A Low-Cost Hyperpolarization Technique For Use With Single-Sided Nmr, Ruth A. Beaver 2020 William & Mary

Adaptation Of A Low-Cost Hyperpolarization Technique For Use With Single-Sided Nmr, Ruth A. Beaver

Undergraduate Honors Theses

Nuclear magnetic resonance (NMR) suffers from inherent signal problems due to low levels of nuclear polarization at room temperature. These problems are especially prevalent in single-sided NMR, which allows for a more flexible measurement geometry and simpler, cheaper instrumentation than traditional NMR. Hyperpolarization techniques can remedy this by providing artificially high levels of polarization for a single measurement. Signal Amplification By Reversible Exchange (SABRE) hyperpolarization is particularly advantageous, since it can be produced quickly using relatively cheap and simple instrumentation. While SABRE hyperpolarization has been successfully demonstrated with traditional NMR, it has not yet been adapted for single-sided NMR. Here ...


Determination Of Thermodynamic Properties Of Non-Protein Amino Acids And Characterization Of Multimers Of Carbamazepine, Gwendylan Turner 2020 William & Mary

Determination Of Thermodynamic Properties Of Non-Protein Amino Acids And Characterization Of Multimers Of Carbamazepine, Gwendylan Turner

Undergraduate Honors Theses

This study has two seemingly unrelated parts that come together remarkably in displaying the comprehensive interplay between chemical structure and properties as well as the variety of analytical applications of mass spectrometry.

The first part of this study describes the determination of thermodynamic properties of several non-protein amino acids using the extended kinetic method. This is a continuation of work started in the Poutsma lab in Spring of 2017. The non-protein amino acids (NPA) studied here hold notable relevance in their unique ability to be mis-incorporated into peptide chains, as shown by the Hartman group at Virginia Commonwealth University.[1 ...


Surface Chemistry And Surface Properties Of Energetic Nitrocellulose (Nc), Henry Grau 2020 Seton Hall University

Surface Chemistry And Surface Properties Of Energetic Nitrocellulose (Nc), Henry Grau

Seton Hall University Dissertations and Theses (ETDs)

This research describes an investigation into the wettability of nitrocellulose (NC), most importantly to nitroglycerin (NG), which are key components of formulations used to propel military ammunition. NG demonstrates complete wetting of NC and, overtime, NG sweats on the NC surface and leaks out. The leaking out of NG from the solid formulation is a known cause of fires and explosions resulting from storage. The origin of this research is inspired by the need to engineer a solution to leakage problems of energetic plasticizer in NC based propellant. While searching for a viable material for a specific application, we journeyed ...


Analysis Of Petroleum Products For Forensic And Environmental Applications, Sarah Ghali, Sarah Porter 2020 Longwood University

Analysis Of Petroleum Products For Forensic And Environmental Applications, Sarah Ghali, Sarah Porter

Student Showcase for Research and Creative Inquiry

In both forensic and environmental applications, it is often important to identify ignitable liquid (IL) residues, to find a suspect or to clean up an oil spill. The ASTM method is commonly used; the extraction methods vary, but the data collection is the same. The instrument used in the ASTM method is gas chromatography mass spectroscopy (GC-MS), which allows a visual identification of the IL contaminating the sample. In this study, the use of Fourier transform infrared spectrometry (FTIR) was used in conjunction with chemometric analysis. Samples were prepared were to simulate an oil spill in natural waters. Two chemometric ...


Analysis Of Phenolic Compounds In Moroccan Olive Oils By Hplc, Hannah Meyls, Sarah Porter 2020 Longwood University

Analysis Of Phenolic Compounds In Moroccan Olive Oils By Hplc, Hannah Meyls, Sarah Porter

Student Showcase for Research and Creative Inquiry

Five extra virgin olive oils collected from farms in Morocco were analyzed for phenolic compounds. To complement these data, the chemical composition of the olive oils were analyzed by high-performance liquid chromatography. Several phenolic compounds were identified and quantified in the olive oils. Specifically, levels of oleuropein and luteolin were quantified in the low mg/kg range, and qualitative comparisons were made between the oil samples for tyrosol, vanillic acid, and apigenin. To compare extraction efficiency of different extraction solvents, methanol and DMF were used.


Surveillance Of Microplastic Pollution In Central Virginia Freshwater Ecosystems, Alexandra Reddy 2020 Liberty University

Surveillance Of Microplastic Pollution In Central Virginia Freshwater Ecosystems, Alexandra Reddy

Senior Honors Theses

Aquatic organisms often mistake microplastic particulates (MP) as food and inadvertently ingest the particulates, which can biomagnify through the food chain. While MP ingestion is well-researched in the marine environment, little is known about microplastics in freshwater  ecosystems. This project explores MP occurrence in an ecologically significant freshwater invertebrate: crayfish. Crayfish from two Central Virginia streams are collected to identify MP in the digestive tracts and gill filaments, and characterize the MP using analytical chemistry techniques. It was determined that MP were present in the digestive tracts and gill filaments of crayfish collected from both streams, and that MP frequency ...


Computational Chemistry - Ulk 101, Michaela Montpas 2020 Olivet Nazarene University

Computational Chemistry - Ulk 101, Michaela Montpas

Scholar Week 2016 - present

Autophagy is a process that generates the necessary building components for cells by cytoplasmic breakdown of unnecessary materials (Martin, Celano, Solitro, Gunaydin, Scott, et. al., 2018). This is a survival technique for cells in times of stress, especially during periods of nutrient starvation. Cancer cells, unfortunately, benefit from this process due to their ability to flourish in nutrient-starved environments, becoming resistant to therapy. The primary protein in mammals responsible for this process is a serine/threonine kinase called ULK 1 (unc-51 like autophagy initiating kinase 1). As such, inhibitors of ULK 1 can be used in cancer therapies in order ...


Phosphorus Nmr And Its Application To Metabolomics, Paula Evans, Fatema Bhinderwala, Robert Powers, Martha Morton, Thomas Smith 2020 University of Nebraska - Lincoln

Phosphorus Nmr And Its Application To Metabolomics, Paula Evans, Fatema Bhinderwala, Robert Powers, Martha Morton, Thomas Smith

UCARE Research Products

Stable isotopes are routinely employed by NMR metabolomics to highlight specific metabolic processes and to monitor pathway flux. 13C-carbon and 15N-nitrogen labeled nutrients are convenient sources of isotope tracers and are commonly added as supplements to a variety of biological systems ranging from cell cultures to animal models. Unlike 13C and 15N, 31P-phosphourous is a naturally abundant and NMR active isotope that doesn’t require an external supplemental source. To date, 31P NMR has seen limited usage in metabolomics because of a lack of reference spectra, difficulties in sample preparation, and an absence of two-dimensional (2D) NMR experiments. But, 31P ...


The Influence Of Radiolytically Produced Nitric Acid On The Corrosion Resistance Of Copper-Coated Used Nuclear Fuel Containers, Joseph P. Turnbull 2020 The University of Western Ontario

The Influence Of Radiolytically Produced Nitric Acid On The Corrosion Resistance Of Copper-Coated Used Nuclear Fuel Containers, Joseph P. Turnbull

Electronic Thesis and Dissertation Repository

In Canada, the proposed disposal method for high level nuclear waste involves sealing the waste in steel containers with a 3 mm outer copper coating and burying it in a deep geologic repository. However, the thickness of the container is significantly reduced making a reassessment of the influence of γ-radiation, emitted by the waste form, on container corrosion a potential licensing requirement. Under humid aerated conditions, the formation of nitric acid is expected, potentially resulting in the formation of droplets or wetted layers on the container surface. Currently available literature on the corrosion of copper in nitric acid does not ...


Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao 2020 University of Massachusetts Amherst

Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao

Doctoral Dissertations

Protein-based therapeutics have emerged as a key driver of rapid growth in drug development pipelines. However, developing such protein drugs is not straightforward in most cases, the existence of physiological barriers greatly restricts the efficient delivery of many therapeutic molecules, and therefore limits their clinical applications. A promising way to address this challenge takes advantage of certain transport protein which can effectively across and enhance the permeability of these barriers, such as transferrin (Tf) which can be internalized by malignant cells and cross physiological barriers via transferrin receptor (TfR)-mediated endocytosis and transcytosis. However, developing such products is impossible without ...


Design, Construction, And Characterization Of A Low-Cost Spectrometer With Interchangeable Parts, Jack Godek 2020 University of Nebraska at Omaha

Design, Construction, And Characterization Of A Low-Cost Spectrometer With Interchangeable Parts, Jack Godek

Student Research and Creative Activity Fair

A low-cost spectrometer was designed for the purpose of teaching spectroscopy. The spectrometer can be built by the student and contains interchangeable pieces such as slit width, grating, and lenses. This will allow the student to understand how changing these variables effects resolution. The spectrometer was constructed from PVC pipe, a plastic electrical box, and a USB webcam. The actual resolution of the spectrometer is close to the theoretical value, depending on which lens and grating is used. In addition, an extra piece can be added that allows absorption spectra to be collected. Having the student piece together the spectrometer ...


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