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Investigation Of The Chemical Interface In The Soybean–Aphid And Rice–Bacteria Interactions Using Maldi-Mass Spectrometry Imaging, Adam T. Klein, Gargey B. Yagnik, Jessica D. Hohenstein, Zhiyuan Ji, Jiachen Zi, Malinda D. Reichert, Gustavo C. Macintosh, Bing Yang, Reuben J. Peters, Javier Vela, Young Jin Lee 2017 Iowa State University

Investigation Of The Chemical Interface In The Soybean–Aphid And Rice–Bacteria Interactions Using Maldi-Mass Spectrometry Imaging, Adam T. Klein, Gargey B. Yagnik, Jessica D. Hohenstein, Zhiyuan Ji, Jiachen Zi, Malinda D. Reichert, Gustavo C. Macintosh, Bing Yang, Reuben J. Peters, Javier Vela, Young Jin Lee

Reuben J. Peters

Mass spectrometry imaging (MSI) is an emerging technology for high-resolution plant biology. It has been utilized to study plant–pest interactions, but limited to the surface interfaces. Here we expand the technology to explore the chemical interactions occurring inside the plant tissues. Two sample preparation methods, imprinting and fracturing, were developed and applied, for the first time, to visualize internal metabolites of leaves in matrix-assisted laser desorption ionization (MALDI)-MSI. This is also the first time nanoparticle-based ionization was implemented to ionize diterpenoid phytochemicals that were difficult to analyze with traditional organic matrices. The interactions between rice–bacterium and soybean ...


Evaluation Of A Filtration Sorbent For Remediation Of Arsenic In Groundwater, Clement Do 2017 California State University - San Bernardino

Evaluation Of A Filtration Sorbent For Remediation Of Arsenic In Groundwater, Clement Do

Electronic Theses, Projects, and Dissertations

A commercially available product, PURA PhosLock, was identified and evaluated for use as a sorbent to remove dissolved arsenic (As) from drinking water. Although marketed as a product to remove phosphate in aquaria, it is composed of iron oxide hydroxide (i.e., FeO(OH)), which is also known to adsorb dissolved As species from water. Arsenic was measured using standard methods and Graphite Furnace Atomic Absorption Spectroscopy. A first rough filtration test was performed to see if the PhosLock adsorbed As well. About 50 g of PhosLock was used to filter 10 L of tap water containing 100 ppb As ...


Apparent Retention Volume Variation With Flow Rate Change In High Performance Liquid Chromatography, Susanne Buntz Erz 2017 Seton Hall University

Apparent Retention Volume Variation With Flow Rate Change In High Performance Liquid Chromatography, Susanne Buntz Erz

Seton Hall University Dissertations and Theses (ETDs)

Recent studies have demonstrated noticeable flow rate dependency of the chromatographic zone retention volume with respect to migration within the empty capillary. This appears to be the result of superposition of asymmetric lateral diffusion and of the laminar flow profile. Although these effects have been studied on empty capillaries, in the presence of the packed column, the retention shift may be insignificant relative to the adsorption-based retention of the analytes. In the case of fast and ultrafast HPLC with short capillary columns, the effect of extra-column caused variation in the analyte retention may constitute an increase of up to 120 ...


Study Of Selectivity In Extraction, Separation, And Detection On Drugs Using Gas Chromatography, Anumeha P. Muthal 2017 Seton Hall University

Study Of Selectivity In Extraction, Separation, And Detection On Drugs Using Gas Chromatography, Anumeha P. Muthal

Seton Hall University Dissertations and Theses (ETDs)

The selectivity of a method is defined by its ability to determine a particular analyte without interference in a complex mixture. Selectivity in gas chromatography (GC) can be obtained at different points in the analysis including the sample preparation, sample introduction, separation on column and detection. In GC, the first dimension of selectivity can be obtained in sample preparation; the second dimension in chromatographic separation and the third dimension in detection. This research focuses on the relationships between selectivity in these different dimensions, studied using some non-steroidal anti-inflammatory drugs, glucocorticoids, fatty acid methyl esters and polycyclic aromatic hydrocarbons. Recent methodologies ...


Ion-Ion Dual-Electrospray Chemistry, Tyler D. Schriber 2017 University of Wyoming

Ion-Ion Dual-Electrospray Chemistry, Tyler D. Schriber

Honors Theses AY 16/17

The research that I have performed since the Spring 2016 semester is based on a study done by Cotham et al. in 2015, where front-end sprayers are used to mix solutions before they enter a mass spectrometer. One of these solutions contains a peptide, which is positively charged, and the other solution contains the reagent 4-formyl-1,3-benzenedisulfonic acid (FBDSA), which is negatively charged. The charges lead to a reaction in microseconds, with spray droplets, before it enters the instrument. Once inside the mass spectrometer a technique called collision induced dissociation (CID) is implemented in order to completely combine the reactant ...


Scanning Tunneling Microscopy And Atomic Force Microscopy In The Characterization Of Activated Graphite Electrodes, Michael S. Freund, Anna Brajter-Toth, Therese M. Cotton, Eric R. Henderson 2017 University of Florida

Scanning Tunneling Microscopy And Atomic Force Microscopy In The Characterization Of Activated Graphite Electrodes, Michael S. Freund, Anna Brajter-Toth, Therese M. Cotton, Eric R. Henderson

Eric Henderson

Sir: To date there have been many methods described to activate carbon electrodes, including electrochemical treatment (1-1 7), laser irradiation (18-21), radio-frequency (RF) plasma (22), and heat treatment (23-26). These methods were developed empirically, and only now is an understanding of parameters controlling surface activity beginning to emerge (20,27). Electrochemical treatment and laser irradiation are particularly attractive treatments because they are relatively inexpensive, are quick, and can be performed without removing the electrode from solution. Activation, common to these procedures, may be attributable to an increase in the exposed edge plane density, which has been associated with faster kinetics ...


Functionalized Silica Gel For Adsorption Of Cesium From Solution, Kenneth Marshall Seaton III 2017 East Tennessee State University

Functionalized Silica Gel For Adsorption Of Cesium From Solution, Kenneth Marshall Seaton Iii

Electronic Theses and Dissertations

Mesoporous silica gel containing embedded phosphotungstic acid (PTA) was synthesized by sol-gel co-condensation of tetraethyl orthosilicate with PTA in acidic media. The obtained material had high Brunauer-Emmett-Teller Theory (BET) surface area and pore volume. A characteristic band of the Keggin structure of PTA was present in its FT-IR spectrum while its X-ray diffraction patterns were absent. This proved the embedding of PTA on a sub-molecular level and not as a second phase. Acidic sites were determined by neutralization with base in aprotic solvent, followed by titration of the remaining base with an acid. The material demonstrated high adsorption capacity of ...


Enzyme Kinetics Studies To Guide Mathematical Modeling Of Microdialysis Sampling To Predict In Situ Biochemistry, Justin M. Klucher 2017 University of Arkansas, Fayetteville

Enzyme Kinetics Studies To Guide Mathematical Modeling Of Microdialysis Sampling To Predict In Situ Biochemistry, Justin M. Klucher

Chemistry & Biochemistry Undergraduate Honors Theses

Microdialysis is a diffusion-based sampling method that can be useful for monitoring various biological systems. Matrix metalloproteinases are a class of enzymes responsible for remodeling the extracellular matrix that, when dysregulated, are linked to various diseases. The delivery method of microdialysis is of particular interest as a sampling technique for enzymatic reactions. Microdialysis was performed in vitro using a model enzyme, porcine pancreatic elastase, because it is a useful substitute for matrix metalloproteinases. A colorimetric substrate for elastase, succinyl-ala-ala-ala-p-nitroanilide, and its product p-nitroaniline were measured using a UV-Vis spectrophotometer. Using an expanded Beer’s Law equation, both analytes’ concentrations were ...


The “Apparent” Diffusion Coefficient Of Electrons Through A Nafion Membrane, Marissa Kayle Reynolds 2017 University of Arkansas, Fayetteville

The “Apparent” Diffusion Coefficient Of Electrons Through A Nafion Membrane, Marissa Kayle Reynolds

Theses and Dissertations

The hydrogen/oxygen fuel cell is a greener, more efficient energy solution. However, there are many problems with the fuel cell including storage, infrastructure, cost, the oxygen reduction reaction, and the durability of the proton exchange membrane (PEM). The PEM is not only used as the electrolyte for the cell but also as a physical barrier between the anode and the cathode. The integrity of this membrane is crucial to the functioning of the fuel cell. This thesis will examine using ferricyanide as a probe molecule for diagnostic experiment of Nafion membrane integrity. Using hydrodynamic voltammetry with a rotating disk ...


An Electrochemical Characterization Of A Vanadium-Based Deoxydehydration Catalyst, Joel Eric Baker 2017 University of Arkansas, Fayetteville

An Electrochemical Characterization Of A Vanadium-Based Deoxydehydration Catalyst, Joel Eric Baker

Theses and Dissertations

Alternative methods for the conversion of polyols into olefins, be it for carbon storage or hydrocarbon fuel production, have become prevalent in today’s chemical industry. One process in particular, deoxydehydration (DODH) has been proven effective in taking sustainable biomass derivatives and converting them through the utilization of various homogenous metal catalysts. While this process may show productive yields and material conversion, it is hindered by the need of a sacrificial reductant. This makes a novel process economically unviable and relatively unused outside of scientific research. That fact begs the question: Can the process be improved? It is proposed here ...


Electrochemical Time Of Flight For Rapid And Direct Measurement Of Diffusion Coefficients, Jonathan C. Moldenhauer 2017 University of Arkansas, Fayetteville

Electrochemical Time Of Flight For Rapid And Direct Measurement Of Diffusion Coefficients, Jonathan C. Moldenhauer

Theses and Dissertations

The determination of diffusion coefficients is of fundamental importance to the understanding of electrochemistry and sensors. Developing a method by which diffusion coefficients of Red/ox active analytes can be determined quickly and elegantly, would be a great advancement over presently accepted methods. This dissertation reports the reviving electrochemical time of flight (ETOF), and developing a method that allows for empirical determination of diffusion coefficients from a single measurement. ETOF is a generate and detect experiment where the time an electrochemically generated species takes to transit a known distance is measured and related to the diffusion coefficient of the species ...


Metalation And Structural Properties Of Apo-Metallothioneins, Gordon W. Irvine 2017 The University of Western Ontario

Metalation And Structural Properties Of Apo-Metallothioneins, Gordon W. Irvine

Electronic Thesis and Dissertation Repository

Metals are required by a quarter of all proteins to achieve their biological function, whether in an active site involved in catalytic chemistry or in a structural capacity. Metals are tightly regulated at the cellular level due to their propensity to cause unwanted side reactions and to be scavenged for use by pathogens. One of the proteins involved in this regulation of metal homeostasis is metallothionein (MT) which is a small, cysteine rich protein primarily involved in the regulation of zinc and copper homeostasis and heavy metal detoxification. MT is unique in its high cysteine content (~30% of the residues ...


Analyzing The Kinetics Of A Bromophenol Blue Fading Reaction In Basic Conditions For An Undergraduate Lab, Zeljka Popovic 2017 Georgia College and State University

Analyzing The Kinetics Of A Bromophenol Blue Fading Reaction In Basic Conditions For An Undergraduate Lab, Zeljka Popovic

Georgia College Student Research Events

Bromophenol blue is a common pH indicator and dye used in many different industries. Once a solution of bromophenol blue is placed in a concentrated basic solution, the color fades from a blue/violet color to clear solution with a pH of 4.6 or greater. The rate law of the reaction is analyzed through the use of a small footprint visible-near-infrared spectrometer (Vis-NIR) with a diode array detector. An absorbance wavelength of 590 nm as a function of time was collected using Ocean Optics OceanView software. The results contained in the data collection file are exported to a spreadsheet ...


Kinetics Of Crystal Violet Color Fading Via A Small Footprint Diode Array Spectrometer, Paige Lott 2017 Georgia College & State University

Kinetics Of Crystal Violet Color Fading Via A Small Footprint Diode Array Spectrometer, Paige Lott

Georgia College Student Research Events

Crystal violet is a pH indicator and is commonly used to classify bacteria. In acidic solutions, crystal violet is yellow in color and at approximately the pH of 1.6, it transitions to a violet color. Over time, this violet color fades as it reacts with the CO 2 in the air until it is clear. A small footprint visible-near- infrared spectrometer (Vis-NIR) with diode array detector was employed in this investigation. Using the software that operates the spectrometer, the absorbance of crystal violet solutions can be measured at 585 nm at high concentrations of base as a function of ...


Characterization Of Α-Anomeric Damaged Dna In Complex With Endonuclease Iv Using Fluorescence Resonance Energy Transfer (Fret), Beatrice Edjah 2017 Georgia State University

Characterization Of Α-Anomeric Damaged Dna In Complex With Endonuclease Iv Using Fluorescence Resonance Energy Transfer (Fret), Beatrice Edjah

Georgia State Undergraduate Research Conference

No abstract provided.


Synthesis Of 1-Phenyl-3,5-Diaryl-4-Bromopyrazoles, 1-Phenyl-3-T-Butyl-5-Aryl-4-Bromopyrazoles, And 1-Phenyl-3-T-Butyl-5-Aryl-4-Bromoisoxazoles., Keren Antoine, Anne K. Jean, Roseleen Almenord, Sierra A. Fleming, Titilope Akinwe, Paula Garzon, Julio C. Falcon 2017 Georgia State University

Synthesis Of 1-Phenyl-3,5-Diaryl-4-Bromopyrazoles, 1-Phenyl-3-T-Butyl-5-Aryl-4-Bromopyrazoles, And 1-Phenyl-3-T-Butyl-5-Aryl-4-Bromoisoxazoles., Keren Antoine, Anne K. Jean, Roseleen Almenord, Sierra A. Fleming, Titilope Akinwe, Paula Garzon, Julio C. Falcon

Georgia State Undergraduate Research Conference

No abstract provided.


Spectrofluorometric Analysis Of Bisphenol-A In Drinking Water Bottles, Jeff Brochetti 2017 Lynchburg College

Spectrofluorometric Analysis Of Bisphenol-A In Drinking Water Bottles, Jeff Brochetti

Student Scholar Showcase

Spectrofluorometric Analysis of Bisphenol-A in Drinking Water Bottles

Bisphenol-A (BPA) is of environmental concern due to its ability to act as an endocrine disruptor in humans and many other animals. In the food industry, BPA is widely used in the production of plastic bottles and plastic liners in aluminum cans. Over time, trace amounts of BPA can leach from the container and into the contents inside. A new method of testing for trace amount of BPA involved the formation of an inclusion complex with ß-Cyclodextrin. With the formation of the inclusion complex, it becomes much easier to analyze low concentrations ...


Determination Of The Zinc Concentration In Human Fingernails By Laser-Induced Breakdown Spectroscopy, Steven J. Rehse, Vlora A. Riberdy, Christopher J. Frederickson 2017 University of Windsor

Determination Of The Zinc Concentration In Human Fingernails By Laser-Induced Breakdown Spectroscopy, Steven J. Rehse, Vlora A. Riberdy, Christopher J. Frederickson

Physics Publications

The absolute concentration of zinc in human fingernail clippings tested ex vivo was determined by 1064 nm laser-induced breakdown spectroscopy and confirmed by speciated isotope dilution mass spectrometry. A nail testing protocol that sampled across the nail (perpendicular to the direction of growth) was developed and validated by scanning electron microscopy energy dispersive x-ray spectroscopy. Using this protocol, a partial least squares regression model predicted the zinc concentration in five subjects’ fingernails to within 7 ppm on average. The variation of the zinc concentration with depth into the nail as determined by laser-induced breakdown spectroscopy was studied and found to ...


The Use Of Ammonia As A Qualitative Test For Determining When Solid Copper Has Completely Precipitated From Aqueous Solutions Containing Copper(Ii) Ions, M. Olivia Byrd, Carl J. Ohrenberg 2017 University of North Georgia

The Use Of Ammonia As A Qualitative Test For Determining When Solid Copper Has Completely Precipitated From Aqueous Solutions Containing Copper(Ii) Ions, M. Olivia Byrd, Carl J. Ohrenberg

Georgia Journal of Science

In this study, two methods were compared to efficiently determine the absence of copper ions from a copper(II) chloride dihydrate (37.274% copper by mass) solution after precipitation using solid magnesium. In one method, a solution color change from pale blue to colorless was used as indication of a completed precipitation of copper. In the alternative method, ammonia was added to aliquots of solution which indicated remaining copper ions with a royal blue complex. For both methods, magnesium turnings were added to a blue copper(II) chloride solution until it was determined, as indicated above, that all copper had ...


Fatty Acid Biomarker Detection For Breast Cancer Using Differential Mobility Spectrometry With Non-Radioactive Ion Source, James Joseph Alberti 2017 University of South Florida

Fatty Acid Biomarker Detection For Breast Cancer Using Differential Mobility Spectrometry With Non-Radioactive Ion Source, James Joseph Alberti

Graduate Theses and Dissertations

Differential Mobility Spectrometry (DMS) using a non-radioactive ion source (NRIS) is investigated as a possible medical diagnostic instrument for near real-time detection of breast cancer biomarkers. In previous clinical studies, concentrations of Linoleic, Palmitic and Stearic fatty acids have been observed at different levels in women with carcinoma breast cancer versus women with benign tumors or healthy women showing no signs of breast cancer. Present diagnostic methods require a biopsy of the suspect tissue and a microscopic lab analysis performed to determine its disease state. This process can take hours or days before the patient and doctor are informed of ...


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