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Extraction Of Indicator Dyes Into Imidazolium-Based Ionic Liquids, Sarah Oplawski 2014 University of Wisconsin Milwaukee

Extraction Of Indicator Dyes Into Imidazolium-Based Ionic Liquids, Sarah Oplawski

Theses and Dissertations

Among the major classes of water pollutants, dyestuffs have proven to be particularly problematic, both in terms of the quantities released to the environment and the difficulties involved in their recovery from aqueous solution. Each year, textile mills worldwide discharge millions of gallons of dye-laden effluents, leading to significant adverse environmental impact as a consequence of the high chemical oxygen demand and toxicity of these effluent streams. For this reason, there has been considerable interest in the development of a means by which to remove dyes from aqueous waste streams. To accomplish this, textile mills generally employ a combination of ...


Crown Ether Stereoisomerism: Implications In Metal Ion Extraction And Ionic Liquid Design, Alan Pawlak 2014 University of Wisconsin Milwaukee

Crown Ether Stereoisomerism: Implications In Metal Ion Extraction And Ionic Liquid Design, Alan Pawlak

Theses and Dissertations

Since their discovery more than four decades ago, crown ethers (CEs) have been the subject of intense investigation in a number of fields. Although many of the structural features that govern the behavior of these compounds have been thoroughly explored, the effect of their stereochemistry has received relatively little attention. In the present work, crown ether stereochemistry is shown to have important implications in both the design of ternary (i.e., three-component) ionic liquids (TILs) and metal ion extraction. Specifically, as a first step toward the development of guidelines for the rational design of ternary ionic liquids employing crown ethers ...


Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry: A High-Throughput Platform In Metabolomics For Assessment Of Lifestyle Interventions In Human Health, Naomi L. Kuehnbaum 2014 McMaster University

Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry: A High-Throughput Platform In Metabolomics For Assessment Of Lifestyle Interventions In Human Health, Naomi L. Kuehnbaum

Open Access Dissertations and Theses

Research in this thesis has focused on development and application of novel methodologies that enhance sample throughput and data fidelity when performing untargeted metabolome profiling by multisegment injection-capillary electrophoresis-mass spectrometry (MSI-CE-MS). Metabolomics is a valuable tool in functional genomics research to investigate underlying molecular mechanisms associated with human health since metabolites are “real-world” end-products of gene expression. CE-MS is well-suited for metabolomics because it is a high efficiency microseparation technique that can be used to resolve complex mixtures of polar metabolites in human biofluids without complicated sample workup. In this thesis, a novel CE-MS assay for estrogens and their intact ...


The Synthesis And Reactivity Of Novel Donor-Acceptor Cyclopropanes And Progress Towards Pyrrolidine Alkaloids, Michael R. Emmett 2014 Western University

The Synthesis And Reactivity Of Novel Donor-Acceptor Cyclopropanes And Progress Towards Pyrrolidine Alkaloids, Michael R. Emmett

University of Western Ontario - Electronic Thesis and Dissertation Repository

The first chapter of this thesis focuses on the synthesis and reactivity of cyclopropane hemimalonates. The cyclopropane hemimalonates can easily be synthesized from 1,1-cyclopropanediesters. The reactivity of cyclopropane hemimalonates with indole under ultra-high pressure conditions leads to ring opened adducts that are complementary to previous research in the Kerr group. The tandem ring opening decarboxylation reaction of cyclopropane hemimalonates led to the synthesis of γ-aminobutyric acid analogues. When an external nucleophile was not present, the cyclopropane hemimalonates could rearrange to form butyrolactones in good to excellent yields. The stereochemical integrity of the cyclopropane hemimalonate is retained through this process ...


Application Of Mn(Iii) Oxidative Cyclizations To Natural Product Synthesis, Bryan Landschoot 2014 Western University

Application Of Mn(Iii) Oxidative Cyclizations To Natural Product Synthesis, Bryan Landschoot

University of Western Ontario - Electronic Thesis and Dissertation Repository

This work begins with a brief review of manganese(III) acetate free radical oxidative cyclization chemistry and its application toward functionalizing nitrogen containing heterocycles. Exploration of a cyclopropane ring opening reaction using indoline, and subsequent manganese(III) cyclization chemistry will be presented as a possible route towards a family of natural products called the flinderoles. Work on the construction of the core of several indole alkaloids from the genus Tabernaemontana, including tronocarpine, chippiine, and dippinine B, will be explored with utilization of manganese(III) cyclizations. Hopes of accessing an advanced common intermediate for each of these natural products will be ...


Electrogenerated Chemiluminescence Of Gold Nanoclusters, Mahdi Hesari 2014 Western University

Electrogenerated Chemiluminescence Of Gold Nanoclusters, Mahdi Hesari

University of Western Ontario - Electronic Thesis and Dissertation Repository

A series of monodispersed AuNCs including Au144(SR)60, Au38(SR)24 and Au25(SR)18z (z =1-, 0 and 1+, SR=2-phenylethanethiol) were prepared. All these nanoclusters showed molecule-like optical and electrochemical properties. These two features are essential for an electrogenerated chemiluminescence or electrochemiluminescence (ECL) study. The Au144(SR)60 showed a small HOMO-LUMO gap determined by electrochemistry. No ECL light was seen in the annihilation process, while NIR ECL was observed with tri-n- propylamine (TPrA) (Chapter 2). ECL was highly efficient in the Au38(SR)24/TPrA co- reactant system. This nanocluster also showed ECL emission with benzoyl ...


Characterization Of Fall Leaves As A Source Of Cellulosic Ethanol, Justin Burum 2014 Minnesota State University, Mankato

Characterization Of Fall Leaves As A Source Of Cellulosic Ethanol, Justin Burum

Journal of Undergraduate Research at Minnesota State University, Mankato

Ethanol is becoming increasingly popular as a fossil fuel additive or substitute. However, current production of ethanol from corn impacts food prices and appears to have an overall low net yield. New sources need to be identified and new processes developed for ethanol production. Cellulosic ethanol is one such new source. Plant material contains a large amount of cellulose and other polysaccharides which are potential feed stocks for ethanol production. The purpose of this experiment was to characterize the polysaccharide, lignin, and ash content of fall leaves to estimate their potential for ethanol production. A slight modification of the NREL ...


Effect Of Sweeteners On The Renin-Angiotensin System In Rats, Jacob Ball 2014 Minnesota State University, Mankato

Effect Of Sweeteners On The Renin-Angiotensin System In Rats, Jacob Ball

Journal of Undergraduate Research at Minnesota State University, Mankato

Normal abundant dietary sugars such as fructose and sucrose can contribute to hypertension and other health issues. To avoid these health complications, many individuals use artificial sweeteners. An equivalent intake of some artificial sweeteners also can lead to hypertension. However, Stevia, a sweetener that is isolated from a Paraguayan plant, was shown in relevant literature to decrease blood pressure in both rat specimens and humans. The general purpose of this research project was to study the effect of Stevia, saccharin, and sucrose on the expression of two key components of the renin-angiotensin- aldosterone system (RAAS): prorenin receptor (PRR) and angiotensin ...


Polyol Induced Extraction (Pie) Of Water From Organic Solvents, Mithilesh Deshpande 2014 Seton Hall University

Polyol Induced Extraction (Pie) Of Water From Organic Solvents, Mithilesh Deshpande

Seton Hall University Dissertations and Theses (ETDs)

Acetonitrile (ACN) is used in huge quantities for Reversed Phase High Performance Liquid Chromatography (RP-HPLC) experiments. For most of the part, these results in waste that is only contaminated with large amounts of water, buffer and trace organic impurities. It would seem worthwhile to purify the ACN from water using a mass separating agent (MSA). In a quest for an MSA, our investigation reveals polyols as a new class of MSAs. It is observed that when a polyol such as glycerol, sorbitol, erythritol, xylitol, Isomalt® or maltitol is added to a mixture of ACN-water, the ACN separates out of the ...


Development Of A Gallium-Containing One-Bead One-Compound Peptide Library For The Discovery Of New Molecular Imaging Probes, Fernanda C. Bononi 2014 Western University

Development Of A Gallium-Containing One-Bead One-Compound Peptide Library For The Discovery Of New Molecular Imaging Probes, Fernanda C. Bononi

University of Western Ontario - Electronic Thesis and Dissertation Repository

An eight amino acid one-bead one-compound (OBOC) peptide library, containing a gallium-DOTA complex, was developed in an attempt to overcome common issues associated with the later addition of radionuclides to peptide chains of imaging probes. The further addition of a radionuclide often changes the binding properties of a peptide, as it adds bulk, and possibly charges. MALDI (matrix-assisted laser desorption ionization) tandem mass spectrometry was determined to be the method of choice in order to deconvolute gallium-containing peptide sequences. The library obtained was screened against the breast cancer cell lines MDA-MB-231 and MCF-7. Positive beads were isolated and sequences were ...


Repurposing Of Human Tyrosine Kinase Inhibitors For Neglected Diseases: Lead Discovery For Chagas Disease, Uma Swaminathan 2014 Northeastern University

Repurposing Of Human Tyrosine Kinase Inhibitors For Neglected Diseases: Lead Discovery For Chagas Disease, Uma Swaminathan

Chemistry Master's Theses

Chapter 1: Neglected tropical disease, Chagas disease and target repurposing approach

The term "Neglected Tropical Diseases" (NTDs) most commonly refers to a group of parasitic and bacterial infectious disease affecting more than one billion people globally. There are 13 core diseases in the NTD group that are widespread across the countries from sub-Saharan Africa, Asia and to Latin America. These diseases primarily occur in rural areas, urban slums or conflict zones and affect 2.7 billion people who live on less than $2 per day, causing considerable morbidity and mortality. NTDs cause severe impact on physical and cognitive development, long-term ...


Au@Tio2 Nanocomposites For The Catalytic Degradation Of Methyl Orange And Methylene Blue: An Electron Relay Effect, Mohammad Mansoob Khan Dr, J. Lee, M. H. Cho 2014 SelectedWorks

Au@Tio2 Nanocomposites For The Catalytic Degradation Of Methyl Orange And Methylene Blue: An Electron Relay Effect, Mohammad Mansoob Khan Dr, J. Lee, M. H. Cho

Dr. Mohammad Mansoob Khan

Au@TiO2 nanocomposites were used for the catalytic degradation of methyl orange and methylene blue by NaBH4. A detail pathway for step by step reduction, oxidation and complete mineralization of intermediates into the respective end-products was established by UV-vis spectroscopy, chemical oxygen demand, ion chromatography and cyclic voltammetry (CV). CV studies confirmed that the dyes were reduced and oxidized to the end-products by NaBH4 in the presence of Au@TiO2 nanocomposites and O2•, •OH and HO2• radicals generated in-situ. Results suggest that Au@TiO2 nanocomposites not only assist in the decolorization of dyes, but also promote their complete mineralization into ...


Exploring Soil Moisture Protocol Alternatives For The Classroom Setting, Garrett Smith 2014 California Polytechnic State University

Exploring Soil Moisture Protocol Alternatives For The Classroom Setting, Garrett Smith

STEM Teacher and Researcher (STAR) Program Posters

Climate change poses a direct threat to future water resources but current climate models suffer from uncertainties regarding the availability of regional water. SMAP or the Soil Moisture Active Passive mission seeks to make improvements to climate models by taking highly accurate, high resolution measurements of global soil moisture. To engage students around the world in a collection of meaningful data that may support the SMAP satellite mission, the Global Learning and Observations to Benefit the Environment program or GLOBE, has forged a partnership with NASA and JPL. GLOBE brings the power of citizen science to the SMAP mission, empowering ...


Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner 2014 California Polytechnic State University

Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner

STEM Teacher and Researcher (STAR) Program Posters

Superamphiphobic surfaces strongly repel both water and oils. In this work, aluminum coupons are processed by sanding with various grit of sand paper to impart microscale roughness. Subsequent submersion of the aluminum substrate in boiling water grows nanoscale grass-like structures. The oxide layer of Al is slightly soluble in water. During a fast diffusion/equilibrium, Al2O3 nanograss grows on the surface. A low energy coating is then deposited on the surface. The micro and nanoscale features create re-entrant structures that trap air enabling contact liquid to be in a Cassie-Baxter state. Superamphiphobicity of the samples were confirmed ...


Determining Force Field Parameters Involved With Metal Organic Framework Synthesis, Marcus A. Tubbs, David Cantu, Vanda Glezakou 2014 California Polytechnic State University

Determining Force Field Parameters Involved With Metal Organic Framework Synthesis, Marcus A. Tubbs, David Cantu, Vanda Glezakou

STEM Teacher and Researcher (STAR) Program Posters

Metal organic frameworks (MOFs) are synthetic materials made of a cage-like lattice with consistently spaced pores. The size of these pores are the defining characteristic of a MOF, as it determines which gases are allowed to pass through and which can be trapped. Examples of their potential use can be greenhouse gas sequestration or storage. Currently, the synthesis of MOFs is based on trial-and-error, and the successes are not well understood. We are working on building the theoretical framework that describes how a particular MOF, MIL-101, comes together during synthesis. Our initial approach was to simulate the possible reactions with ...


Laboratory Evaluation Of Black Carbon Deposition Onto Snow And Transport Via Snowmelt, Larry D. Hermanson, Joshua P. Schwarz 2014 California Polytechnic State University

Laboratory Evaluation Of Black Carbon Deposition Onto Snow And Transport Via Snowmelt, Larry D. Hermanson, Joshua P. Schwarz

STEM Teacher and Researcher (STAR) Program Posters

Black carbon (BC) is an aerosol material produced by incomplete combustion of fossil fuels and biomass. BC has been shown to be the second most important anthropogenic climate warming agent after carbon dioxide due to its ability to absorb solar radiation, influence cloud behavior, and accelerate snow melt. BC in otherwise clean snow can significantly reduce its reflectivity. In order to learn about the significance of BC contamination in snow, we explored the deposition of BC onto snow and the transport of BC in snow during snowmelt. A Single Particle Soot Photometer (SP2), was used to measure the concentration and ...


Characterization Of Organic Carbon In Sediments From Old Rifle, Co, A Former Uranium Mill, Francis Michael Tee, Morris Jones, Sharon Bone, Michael Schaefer, Scott Fendorf, John Bargar 2014 California Polytechnic State University

Characterization Of Organic Carbon In Sediments From Old Rifle, Co, A Former Uranium Mill, Francis Michael Tee, Morris Jones, Sharon Bone, Michael Schaefer, Scott Fendorf, John Bargar

STEM Teacher and Researcher (STAR) Program Posters

Characterization of sediments from Old Rifle, CO, a former uranium mill

More than 34 million gallons (~129 million liters) of groundwater are contaminated with uranium at Old Rifle, Colorado – a former uranium-processing site that operated until 1958. The original Department of Energy strategy for remediation, involving natural flushing of U from the groundwater through mixing with surface water, has not been as successful as predicted. The uranium plume is replenished when insoluble U(IV) is oxidized to the more mobile U(VI). Relatively thin pockets of silt-, clay-, and organic-rich sediments contain reduced uranium, iron and sulfur and are referred ...


Detecting Non-Seismic Precursor Earthquake Signals Using Tree Antennas, Jaqueline O. Lopez 2014 California Polytechnic State University

Detecting Non-Seismic Precursor Earthquake Signals Using Tree Antennas, Jaqueline O. Lopez

STEM Teacher and Researcher (STAR) Program Posters

Forecasting earthquakes has yet to be achieved. However, there are numerous non-seismic precursor signals, which become detectable weeks to days before major events – for instance changes in Earth’s electrical surface potential. These changes are due to the arrival of positive electronic charge carriers, known as positive holes, stress-activated deep in the Earth’s crust, in the hypocenter of the future earthquake. Trees can be used as antennas for detecting the surface potential changes due to these mobile charges. This configuration allows for the detection of diurnal variations of the ground potential. Although we only had 105 days worth of ...


Selective Oxidations By Iron(Iii) Porphyrins And Iron(Iii) Corroles, Aaron Dalnamath Carver 2014 Western Kentucky University

Selective Oxidations By Iron(Iii) Porphyrins And Iron(Iii) Corroles, Aaron Dalnamath Carver

Masters Theses & Specialist Projects

The selective oxidation of organic compounds represents a leading technology for chemical industries. They are used in chemical synthesis in the pharmaceutical and petrochemicals industries, and possible the decontamination of harmful substances. However, oxidations reaction are among the most challenging processes to control. Many stoichiometric oxidants with heavy metals are expensive, or toxic maybe both, and therefore unfeasible to be utilized. The ideal processes for catalytic oxidation would use molecular oxygen or hydrogen peroxide as the primary oxygen source, with transition metal catalysts to mimic the predominant oxidation catalysts in Nature, the cytochrome P450 enzymes. This study focuses on the ...


Ice Caves On Extraterrestrial Bodies: What Are The Prospects For Speleogenesis And Detection?, Penelope J. Boston 2014 University of South Florida

Ice Caves On Extraterrestrial Bodies: What Are The Prospects For Speleogenesis And Detection?, Penelope J. Boston

The International Workshop on Ice Caves

Potential mechanisms for creating cavities in icy extraterrestrial bodies have been tentatively explored by several authors. On one hand we have examples of mechanisms that create caves in water ice here on Earth. In addition, there may be unique mechanisms on other Solar System objects that do not occur on Earth but might produce cavities, e.g. sublimation of comets upon perihelion passage. The methods of detecting such cavities depend upon the nature of the icy body in question, the potential for orbital or landed missions to visit those bodies in the future, and remote or landed methods for detecting ...


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