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Analysis Of Metallic Components Of Gsr From Various Types Of Ammunition And Firearms Utilizing An Sem-Edx, Jenna A. Campbell 2018 Duquesne University

Analysis Of Metallic Components Of Gsr From Various Types Of Ammunition And Firearms Utilizing An Sem-Edx, Jenna A. Campbell

Graduate Student Research Symposium

Gunshot residue (GSR) is a chemical reaction that occurs when a firearm is discharged, which emits a cloud of gases from the barrel of the gun. It consists of both the burned and unburned propellant and primer components. These components are either organic or inorganic in nature, respectively. The organic components are located in the gunpowder part of the bullet, while the inorganic components are located in the primer part of the bullet. The primer consists of lead, barium, and antimony. These elements are considered heavy metals. Additionally, lead, barium, and antimony are the three key elements found in the ...


Assessment Of The Viability Of Microwell Plates As Sample Holders For Analytical Excitation-Emission Spectroscopy Of Polyaromatic Hydrocarbons In 75% Ethanol, Lauren M. Ridley-Hoffman 2018 Seton Hall University

Assessment Of The Viability Of Microwell Plates As Sample Holders For Analytical Excitation-Emission Spectroscopy Of Polyaromatic Hydrocarbons In 75% Ethanol, Lauren M. Ridley-Hoffman

Seton Hall University Dissertations and Theses (ETDs)

Polyaromatic hydrocarbons (PAHs) in the environment are a significant concern as many compounds in this class are potential carcinogens. PAHs resulting from petroleum spills can contaminate natural waters and the products obtain from them (fish and fish products in particular). Previous studies by Pena, et. al. on ethanolic extracts of organs from menhaden captured in the vicinity of the Deepwater Horizon (Macondo oil well) spill have shown that fluorescence excitation spectroscopy is a useful technique for detecting the presence of PAH metabolites and fluorescent vitamins. The study has also concluded that previous methods for analyzing PAHs using fluorescence spectroscopy used ...


Assessment Of Energetic Heterogeneity Of Reversed-Phase Surfaces Using Excess Adsorption Isotherms For Hplc Column Characterization, Leih-Shan Yeung 2018 Seton Hall University

Assessment Of Energetic Heterogeneity Of Reversed-Phase Surfaces Using Excess Adsorption Isotherms For Hplc Column Characterization, Leih-Shan Yeung

Seton Hall University Dissertations and Theses (ETDs)

This research is to explore a more general column categorization method using the test attributes in alignment with the common mobile phase components. As we know, the primary driving force for solute retention on a reversed-phase surface is hydrophobic interaction, thus hydrophobicity of the column will directly affect the analyte retention. This research describes a method to determine the column hydrophobicity by the ratio of adsorbed acetonitrile and methanol to water on the column surface using excess adsorption isotherm estimation. An excess adsorption isotherm for a binary mobile phase system represents a competitive interaction of both solvent components with the ...


Kinetics And Activation Energy Parameters For Hydrolysis Of Acetic Anhydride In A Water-Acetone Cosolvent System, Samson Olowoyo 2018 East Tennessee State University

Kinetics And Activation Energy Parameters For Hydrolysis Of Acetic Anhydride In A Water-Acetone Cosolvent System, Samson Olowoyo

Electronic Theses and Dissertations

The hydrolysis of acetic anhydride is a widely-studied liquid phase reaction studied since 1906. Different approaches have been used to study the kinetics of this reaction. Approaches used by researchers have involved the use of sophisticated experimental set-ups. In this work, the pH technique has been adopted which involves the use of a pH meter to monitor the hydrolysis reaction. Analysis of the hydrolysis reaction has been performed for water/acetone cosolvent systems over a range of temperatures and mole fractions. Eyring analysis was performed under isomole fraction conditions and activation enthalpy, entropy, and Gibbs free energy for hydrolysis of ...


Eyring Activation Energy Analysis Of Acetic Anhydride Hydrolysis In Acetonitrile Cosolvent Systems, Nathan Mitchell 2018 East Tennessee State University

Eyring Activation Energy Analysis Of Acetic Anhydride Hydrolysis In Acetonitrile Cosolvent Systems, Nathan Mitchell

Electronic Theses and Dissertations

Acetic anhydride hydrolysis in water is considered a standard reaction for investigating activation energy parameters using cosolvents. Hydrolysis in water/acetonitrile cosolvent is monitored by measuring pH vs. time at temperatures from 15.0 to 40.0 °C and mole fraction of water from 1 to 0.750. This work utilizes a temperature controlled water bath and a Vernier glass-body pH probe with Vernier Logger Pro 3.10.1 software for automated data collection. Data analysis is used to determine observed kinetic rate constants under the assumption that hydrolysis is a pseudo-first-order reaction. Eyring plots were used to compare activation ...


Gas-Phase Hydrogen-Deuterium Exchange And Fragmentation Studies Of Tetrapeptides Containing Lysine And Its Homologs, AnnaTram Do 2018 College of William and Mary

Gas-Phase Hydrogen-Deuterium Exchange And Fragmentation Studies Of Tetrapeptides Containing Lysine And Its Homologs, Annatram Do

Undergraduate Honors Theses

Mass spectrometry- based proteomics is becoming a common method in proteomics. Peptides can be identified by automated database searches, and relative protein abundances can be obtained from the mass spectra. Understanding the fragmentation mechanisms may refine and provide additional "rules" that will increase the confidence in automated primary sequencing of peptides and eventually relate the information on gas-phase fragmentation patterns and energetics of dissociation to the gas-phase conformations of intact and fragment peptides and proteins; this will improve protein identification and profiling. Improvements are necessary for continual use of these quantitative approaches and bottom-up proteomics.

Lysine and its homologs, ornithine ...


Design And Development Of A Quartz Crystal Microbalance Immunosensor For Exosomes, Wesley Cox 2018 University of Tennessee, Knoxville

Design And Development Of A Quartz Crystal Microbalance Immunosensor For Exosomes, Wesley Cox

University of Tennessee Honors Thesis Projects

No abstract provided.


Development Of Microdialysis Probes In Series Approach Toward Eliminating Microdialysis Sampling Calibration: Miniaturization Into A Pdms Microfluidic Device, Randy Espinal Cabrera 2018 University of Arkansas, Fayetteville

Development Of Microdialysis Probes In Series Approach Toward Eliminating Microdialysis Sampling Calibration: Miniaturization Into A Pdms Microfluidic Device, Randy Espinal Cabrera

Theses and Dissertations

A new microdialysis sampling method and microfluidic device were developed in vitro. The method consisted of using up to four microdialysis sampling probes connected in series to evaluate the relative recovery (RR) of different model solutes methyl orange, fluorescein isothiocyanate (FITC)-dextran average mol. wt. 4,000 (FITC-4), FITC-10, FITC-20, and FITC-40. Different flow rates (0.8, 1.0, and 1.5 µL/min) were used to compare experimentally observed relative recoveries with theoretical estimations. With increasing the number of probes in series, the relative recovery increases and ~100% (99.7% ± 0.9%) relative recovery for methyl orange was obtained ...


Development Of Rules Of Attraction For Intercalated Guest Molecules Inside Of A Hydrogen Bonded Framework, Matthew Fischer 2018 University of Missouri-St. Louis

Development Of Rules Of Attraction For Intercalated Guest Molecules Inside Of A Hydrogen Bonded Framework, Matthew Fischer

Dissertations

Supramolecular chemistry has synthesized large and small molecules which host guest molecules for several decades. What started as a way to mimic of enzymes in nature, has exploded into a sea of materials such as porous coordination polymers, low-density metal-organic frameworks, inclusion compounds, and hydrogen bonded frameworks. We previously designed a layered framework consisting of a metal complex with coordinate covalent ligands. These ligands have peripheral carboxylic acid groups which hydrogen bond to organic pillars containing terminal amines. The layered structure is separated by these pillars, which are closed-packed, creating 1-dimensional channels able to co-crystallize molecules. There is interest in ...


Evaluation Of Vaporization Enthalpies And Vapor Pressures Of Various Aroma And Pharmacologically Active Compounds By Correlation Gas Chromatography, Daniel Simmons 2018 University of Missouri, St. Louis

Evaluation Of Vaporization Enthalpies And Vapor Pressures Of Various Aroma And Pharmacologically Active Compounds By Correlation Gas Chromatography, Daniel Simmons

Theses

Scientists in the pharmaceutical, food, and aroma industries can benefit from reliable thermochemical data. Vaporization enthalpy and vapor pressure data are not available for all compounds. Furthermore, some literature data is conflicting. The goal of this work was to use a method called correlation gas chromatography (CGC) to generate reliable vaporization enthalpy data in instances where other experimental methods are not applicable. Vapor pressures of the targets were also calculated in cases where the required literature data on the standards used in this technique were available.

CGC involves making a standard cocktail that includes a mixture of standards and one ...


Eating Crickets? Nutrient Mineral Content Of Two Cricket Species And Chapul Cricket Protein Bars Using Mp-Aes, Nathan Hopkins 2018 Lynchburg College

Eating Crickets? Nutrient Mineral Content Of Two Cricket Species And Chapul Cricket Protein Bars Using Mp-Aes, Nathan Hopkins

Student Scholar Showcase

Global agriculture is beset by numerous challenges which must be surmounted to feed a developing world, from combating climate change to the cultivation of sustainable food products. This, in addition to protein and nutrient deficiencies in the developing world, makes considering alternative protein sources, such as a crickets, an attractive option. Crickets use a fraction of the land and water that protein sources like beef cattle do, and can be cultivated in urban environments in stacked boxes. This research investigation aims to quantify the nutrient mineral content (Iron, Sodium, Potassium, Calcium, and Magnesium) of two cricket species (Acheta domesticus & Gryllodes ...


Electrochemical And Corrosion Examination Of Copper Under Deep Geologic Conditions For The Application Of Nuclear Waste Containers, Taylor L. Martino 2018 The University of Western Ontario

Electrochemical And Corrosion Examination Of Copper Under Deep Geologic Conditions For The Application Of Nuclear Waste Containers, Taylor L. Martino

Electronic Thesis and Dissertation Repository

Copper is the selected material for the fabrication of nuclear fuel waste containers in Sweden, Finland and Canada due to its corrosion resistance in the anoxic aqueous environments, anticipated in deep geological repositories. A potential oxidant for copper is bisulphide produced either by the dissolution of minerals or by sulphate-reducing bacteria. The primary goals of this thesis were to determine the mechanism of corrosion of copper in bisulphide environments and to investigate the chemistry of the bentonite porewater that will ultimately be in contact with the copper container.

The mechanism of sulphide film growth and the details of copper corrosion ...


Monitoring The Stimulated Uncapping Process Of Gold-Capped Mesoporous Silica Nanoparticles, Ashley E. Augspurger, Xiaoxing Sun, Brian G. Trewyn, Ning Fang, Anthony S. Stender 2018 Iowa State University and Ames Laboratory

Monitoring The Stimulated Uncapping Process Of Gold-Capped Mesoporous Silica Nanoparticles, Ashley E. Augspurger, Xiaoxing Sun, Brian G. Trewyn, Ning Fang, Anthony S. Stender

Ames Laboratory Accepted Manuscripts

To establish a new method for tracking the interaction of nanoparticles with chemical cleaving agents, we exploited the optical effects caused by attaching 5–10 nm gold nanoparticles with molecular linkers to large mesoporous silica nanoparticles (MSN). At low levels of gold loading onto MSN, the optical spectra resemble colloidal suspensions of gold. As the gold is removed, by cleaving agents, the MSN revert to the optical spectra typical of bare silica. Time-lapse images of gold-capped MSN stationed in microchannels reveal that the rate of gold release is dependent on the concentration of the cleaving agent. The uncapping process was ...


A High Throughput Approach For The Generation Of Orthogonally Interacting Protein Pairs, Justin Lawrie, Xi Song, Wei Niu, Jiantao Guo 2018 University of Nebraska-Lincoln

A High Throughput Approach For The Generation Of Orthogonally Interacting Protein Pairs, Justin Lawrie, Xi Song, Wei Niu, Jiantao Guo

Faculty Publications -- Chemistry Department

In contrast to the nearly error-free self-assembly of protein architectures in nature, artificial assembly of protein complexes with pre-defined structure and function in vitro is still challenging. To mimic nature’s strategy to construct pre-defined three-dimensional protein architectures, highly specific proteinprotein interacting pairs are needed. Here we report an effort to create an orthogonally interacting protein pair from its parental pair using a bacteria-based in vivo directed evolution strategy. This high throughput approach features a combination of a negative and a positive selection. The newly developed negative selection from this work was used to remove any protein mutants that retain ...


Analysis Of Veterinary Drug Residues In Imported And Domestic Crawfish Using Liquid Chromatography—Mass Spectrometry, Emily Kate Wall 2018 Louisiana State University and Agricultural and Mechanical College

Analysis Of Veterinary Drug Residues In Imported And Domestic Crawfish Using Liquid Chromatography—Mass Spectrometry, Emily Kate Wall

LSU Master's Theses

Aquaculture production has greatly increased over the past few decades, and will continue to grow as the world fisheries become overfished and demand for seafood increases. With increased production comes more intense cultivation methods and heavy use of formulated feeds that may contain veterinary drug residues. Currently no antibiotics are allowed in the U.S. for crawfish aquaculture; yet, detectable levels of various antibiotics have been found in imported seafood samples.The FDA is responsible for testing aquaculture products entering the United States, but only has the capabilities to test a minimal amount of those imports. Additionally, for crawfish there ...


Abnormal Phase Transition Between Two-Dimensional High-Density Liquid Crystal And Low-Density Crystalline Solid Phases, Wenbin Li, Longjuan Kong, Baojie Feng, Huixia Fu, Hui Li, Xiao Cheng Zeng, Kehui Wu, Lan Chen 2018 University of Chinese Academy of Sciences

Abnormal Phase Transition Between Two-Dimensional High-Density Liquid Crystal And Low-Density Crystalline Solid Phases, Wenbin Li, Longjuan Kong, Baojie Feng, Huixia Fu, Hui Li, Xiao Cheng Zeng, Kehui Wu, Lan Chen

Xiao Cheng Zeng Publications

Some two-dimensional liquid systems are theoretically predicted to have an anomalous phase transition due to unique intermolecular interactions, for example the first-order transition between two-dimensional high-density water and low-density amorphous ice. However, it has never been experimentally observed, to the best of our knowledge. Here we report an entropy-driven phase transition between a high-density liquid crystal and low-density crystalline solid, directly observed by scanning tunneling microscope in carbon monoxide adsorbed on Cu(111). Combined with first principle calculations, we find that repulsive dipole–dipole interactions between carbon monoxide molecules lead to unconventional thermodynamics. This finding of unconventional thermodynamics in two-dimensional ...


Carbon Quantum Dots: Bridging The Gap Between Chemical Structure And Material Properties, Timothy J. Pillar-Little Jr. 2018 University of Kentucky

Carbon Quantum Dots: Bridging The Gap Between Chemical Structure And Material Properties, Timothy J. Pillar-Little Jr.

Theses and Dissertations--Chemistry

Carbon quantum dots (CQDs) are the latest generation of carbon nanomaterials in applications where fullerenes, carbon nanotubes, and graphene are abundantly used. With several attractive properties such as tunable optical property, edge-functionalization, and defect-rich chemical structure, CQDs have the potential to revolutionize optoelectronics, electro- and photocatalysis, and biomedical applications. Chemical modifications through the addition of heteroatoms, chemical reduction, and surface passivation are found to alter the band gap, spectral position, and emission pathways of CQDs. Despite extensive studies, fundamental understanding of structure-property relationship remains unclear due to the inhomogeneity in chemical structure and a complex emission mechanism for CQDs.

This ...


Interfacial Corrosion Of Copper And The Formation Of Copper Hydroxychloride, Mary Teague, Shengxi Li, Hongbo Cong 2018 The University of Akron

Interfacial Corrosion Of Copper And The Formation Of Copper Hydroxychloride, Mary Teague, Shengxi Li, Hongbo Cong

Honors Research Projects

Electrical circuitry is an industry, among many others, heavily using the element of copper. Ensuring the mechanical integrity of Cu is crucial, especially in salt environments, for the multifaceted composition of circuits. 4N NaCl solution (equilibrium concentration in ~84% RH) simulated this three-phase system. Rectangular Cu samples were partially immersed in both ambient and continuous lab air sparging atmospheres to understand waterline corrosion of the metal. Open circuit potentials (OCP) were continuously taken during the immersion testing for a maximum of 5 days. A scanning electron microscopy (SEM) equipped with an energy dispersive X-ray spectrometer (EDS), Raman spectroscopy, and 3-D ...


Tandem Mass Spectrometry (Ms/Ms) For Determination Of Architecture Of Synthetic Polymers, Shoumik Saha 2018 The University of Akron

Tandem Mass Spectrometry (Ms/Ms) For Determination Of Architecture Of Synthetic Polymers, Shoumik Saha

Honors Research Projects

Tandem Mass Spectrometry (MS/MS) was used to determine the architecture of synthetic polymers and they are difluorene-N3, 3-difluorene-N3 and VPOSS-3-difluorene. VPOSS materials usually exhibit electrochemical properties and the research was performed to determine their accurate structure and to provide evidence of their proper synthesis. The compounds were mixed with a matrix solution, DCTB, and a silver salt to enable proper protonation. The solvent mixture was on a MALDI plate and then put into the mass spectrometer. The mass spectrum generated was analyzed and each fragment was identified to structures with the synthetic polymers via ChemDraw. Thus, trial ...


Development Of A High Performance Liquid Chromatography Method For The Analysis Of Next-Generation Cyanide Antidote, 3-Mercaptopyruvate, In Plasma, Elaf Alzhrani 2018 South Dakota State University

Development Of A High Performance Liquid Chromatography Method For The Analysis Of Next-Generation Cyanide Antidote, 3-Mercaptopyruvate, In Plasma, Elaf Alzhrani

Electronic Theses and Dissertations

Although the current FDA approved cyanide antidotes (i.e., sodium nitrite, sodium thiosulfate, and hydoxocoboalamine) are effective for treating cyanide poisoning, each individual antidote has major limitations, including large effective dosage, delayed onset of action, or dependence on enzymes generally confined to specific organs. To overcome these current limitations, next-generation cyanide antidotes are being investigated, including 3-mercaptopyruvate (3-MP). Analytical methods capable of detecting 3-MP from plasma are essential for the development of 3-MP as a nextgeneration cyanide antidote. Although 3-MP has been analyzed by LC-MS-MS, this instrument is not widely available. Therefore, a high performance liquid chromatography (HPLC) method with ...


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