Physical Sciences and Mathematics Commons^™

An Optical-Fiber Based Sensor Array For The Simultaneous Analysis Of Zinc And Copper In Aqueous Environments, Steven Kopitzke

Theses and Dissertations

Copper and zinc are elements commonly used in industrial applications, with many of these processes using these elements in aqueous environments. Before the solutions can be discharged into civil or native waterways, waste treatment processes must be undertaken to ensure compliance with federal, state and local guidelines restricting the concentration of ions discharged in solution. While there are methods of analysis currently available to monitor these solutions, each method has disadvantages, be it that they are cost prohibitive, inaccurate, and/or time-consuming. In this work, a new optical fiber-based platform capable of providing fast and accurate results when performing solution analysis …

Functional Organic Nanomaterials, Ryan R. Kohlmeyer

Theses and Dissertations

π-Conjugated polymers have a wide range of applications such as photovoltaics, light-emitting diodes, and sensors. To gain a better understanding of these systems, monodisperse oligomers can be used as a more simplistic model to generate predictive structural and physical properties of corresponding polymers. A divergent/convergent synthetic approach to synthesis of monodisperse π-conjugated oligomers has been developed. These well-defined, thiophene-containing molecular building blocks have been successfully coupled to a ferrocene hinge, which has been found to be highly efficient in the transport of gold atoms using a gold scanning tunneling microscopy tip.

Carbon nanotubes (CNTs) represent a rare class of materials, …

Characterization Of The Distribution, Abundance, And Fate Of Metals In Sediment, April Grant

Theses and Dissertations

This research describes the mobility of heavy metals in river sediment through characterization of metal-sediment association by a sequential extraction procedure. The most abundant isotopes of As, Cd, Cu, Cr, Pb and Zn were measured by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) in four sediment extraction phases: a) exchangeable, b) carbonate-bound, c) metal-oxide-bound, and d) organic-bound. The measured concentrations were compared to the Wisconsin Department of Natural Resources' "Sediment Quality Guidelines" to determine whether the metals were present at toxic levels. Two reference techniques, Potentiometric Stripping Analysis and Graphite Furnace Atomic Absorption Spectroscopy, were used to validate the concentrations of metals …

Infrared Light Induced Bending Of Liquid Crystalline Elastomer Composite-Silicone Bilayer Films, Maika Moua

Theses and Dissertations

This research centers on infrared (IR) light-induced bending of liquid crystalline elastomers (LCE) composite-silicone bilayer films. Two new developments are presented in this thesis. First, the reversible infrared (IR) induced bending of 0.1% (w/w) single walled nanotube (SWNT)-LCE/silicone bilayer films were successfully prepared and used for fabrication of functioning devices such as folding, grabbing, and crawling structures. Second, the use of adding a filler (absorbs specific wavelength range), such as Dye 1002, into the LCE matrix achieved wavelength selectivity in LCE systems. The 0.2% (wt/wt) Dye 1002-LCE/silicone bilayer films demonstrated bending under a 980 nm laser source but no bending …

High-Throughput Approaches For The Assessment Of Factors Influencing Bioavailability Of Small Molecules In Pre-Clinical Drug Development, Megan Marie Mccallum

Theses and Dissertations

A bioactive molecule must pass many hurdles to be designated as a "good" pharmaceutical lead or hit compound. It should have a significant activity, selectivity, bioavailability, and metabolic half-life. Many factors have been identified that influence the free drug concentration or bioavailability of orally administered drugs in the earliest development stages. In vitro pre-clinical assays have been developed to measure these parameters. The small molecule properties that are investigated here include aqueous solubility, permeability, reactivity (electrophilicity), small molecule-protein binding, and displacement of protein-bound molecules (drug-drug interactions). The development of rapid and miniaturized assays to quantify these factors is presented herein. …

Methods In Metallomics, Proteomics, And Toxicology: Development And Applications Of Laser Ablation Inductively Coupled Plasma Mass Spectrometry And Native Sds-Page, William John Wobig

Theses and Dissertations

Polyacrylamide gel electrophoresis (PAGE) is a bio-analytical method used to separate proteins in solution into an array of individual bands of proteins in a gel matrix. Current PAGE methods, however, have severe limitations in simultaneously maintaining a protein's native structure and association with transition metals while providing adequate resolution. Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) provides a means to perform trace to ultra-trace level inorganic analysis of solid samples such as dried PAGE gels containing metallo-protein arrays. Current LA-ICP-MS methods involving the analysis of PAGE gels, however, have been limited in their effective use by inadequate limits of …

Anion Effects In The Extraction Of Metal Ions Into Room-Temperature Ionic Liquids (Rtils), Sarah Lynn Garvey

Theses and Dissertations

As part of a broader program directed at the development of improved approaches to the removal of actinides and heat-producing fission products from spent nuclear fuel, the fundamental aspects of the partitioning of selected metal ions between aqueous solution and various room-temperature ionic liquids (ILs) containing a neutral extractant have been investigated.

Prior work has shown that in contrast to the partitioning of alkaline earth cations into conventional solvents in the presence of a crown ether, which is known to proceed via a single pathway (i.e., neutral complex extraction), their extraction into an IL is often a complex, multi-path process …

Part 1. Design And Synthesis Of Cysteine/Cystine Prodrugs And Bioisosteres Including Symmetrical And Unsymmetrical Disulfides Designed To Increase Cystine Levels In The Cns In Order To Drive The Cystine/Glutamate Antiporter: A Novel Treatment For Schizophrenia And Drug Addiction. Part 2. Design And Synthesis Of Subtype Selective Ester Bioisosteres Of Bzr Ligands For Gabaa/Benzodiazepine Receptors To Enhance Metabolic Stability, Edward Merle Johnson Ii

Theses and Dissertations

Part 1. Schizophrenia is a debilitating disorder that affects almost 1% of the world's population; pharmacotherapy expenditures for this disorder exceed $10 billion dollars even though existing medications exhibit a poor safety/efficacy profile. It is estimated that 75% of patients discontinue drug treatment, in part due to poor safety/efficacy. The current data set demonstrates that cysteine prodrug NAC reverse the behavioral and neurochemical effects of PCP used to model schizophrenia.

As a result cysteine prodrugs represent a highly novel approach to treating schizophrenia; indeed, these compounds may ultimately be more effective than existing medications because these drugs target the pathology …

Mitochondrial Targeting In Photodynamic Therapy. Metabolic And Drug Structure Requirements For Specific Mitochondrial Localization. A Pilot Investigation, Melissa Rhea Pergande

Theses and Dissertations

Photodynamic therapy (PTD) has shown promise in the treatment of certain types of cancer (Davis et al. 1985, Chen 1988). One appealing strategy under consideration to selectively target tumor cells in PDT is that of mitochondrial targeting (Chen 1988, Chen 1989). The concept of mitochondrial targeting has its origin in the pioneering observation by Chen and colleagues that an enhanced mitochondrial transmembrane potential (ΔΨmito) is a prevalent tumor cell phenotype (Davis et al. 1985, Chen 1988). Because the plasma transmembrane potential is negative on the inner side of the cell, and the mitochondrial transmembrane potential is negative on the matrix …

The Measure And Instruction Of Scale In Introductory Chemistry, Karrie Linn Gerlach

Theses and Dissertations

As a student, it is fundamental to comprehend how small an atom or molecule is in order to truly understand how the world works. The American Association for the Advancement of Science (AAAS) has determined that scale is a critical theme that pervades through all areas of science and is critical to a deep understanding. This project determined that students, which are more proficient with scale and moving between the macroscopic and particle worlds, were better performers in chemistry classes. Interviews were used to determine what the students understood and what common misconceptions were present. These lead to the development …

Part I. The First Enantiospecific, Stereospecific Total Synthesis Of The Indole Alkaloid Ervincidine. Part Ii. The Synthesis Of Alpha 5 Subtype Selective Ligands For Gaba(A) /Benzodiazepine Receptors, Sundari K. Rallapalli

Theses and Dissertations

Part I. The first enantiospecific, stereospecific total synthesis of ervincidine 89 has been accomplished from commercially available D-(+)-tryptophan 37 which has served both as the chiral auxiliary and the starting material. Moreover, this is the first synthesis which unequivocally sets the stereochemistry of the hydroxyl group at C-6 in sterospecific fashion, as well as the C-16 hydroxy methyl group. The stereospecific conversion of D-(+)-tryptophan 37 into the key template (−)-Na-H, Nb-benzyl tetracyclic ketone 49 via the asymmetric Pictet-Spengler reaction (600 gram scale) and Dieckmann cyclization on multi-hundred gram scale was reduced to only two reaction vessels. The optically active tetracyclic …

Rapid Knowledge Assessment (Rka): Assessing Students Content Knowledge Through Rapid, In Class Assessment Of Expertise, Erin Margaret O'Connell

Theses and Dissertations

Understanding how students go about problem solving in chemistry lends many possible advantages for interventions in teaching strategies for the college classroom. The work presented here is the development of an in-classroom, real-time, formative instrument to assess student expertise in chemistry with the purpose of developing classroom interventions. The development of appropriate interventions requires the understanding of how students go about starting to solve tasks presented to them, what their mental effort (load on working memory) is, and whether or not their performance was accurate. To measure this, the Rapid Knowledge Assessment (RKA) instrument uses clickers (handheld electronic instruments for …

Structure And Chemistry Of Model Catalysts In Ultrahigh Vacuum, Joshua D. Walker

Theses and Dissertations

The study of catalysis is a key area of focus not only in the industrial sector but also in the nature and biological systems. The market for catalysis is a multi-billion dollar industry. Many of the materials and products we use on a daily basis are formed through a catalytic process. The quest to understanding and improving catalytic mechanisms is ongoing. Many model catalysts use transition metals as a support for chemical reactions to take place due to their selectivity and activity. Palladium, gold, and copper metals are studied in this work and show the ability to be catalytically reactive. …

Fundamental And Applied Studies Of Metal Ion Extraction By Crown Ethers Into Imidazolium-Based Room Temperature Ionic Liquids, Cory Hawkins

Theses and Dissertations

Growing recognition of the extraordinary physicochemical properties and unique solvation environment afforded by ionic liquids (ILs) has drawn increasing attention to these solvents as media for chemical separations. Until recently, little was known about how ionic liquids behave as solvents in this application, particularly in the extraction of ionic solutes such as metal ions. In contrast to the single pathway observed using molecular diluents (i.e., neutral complex extraction), metal ion extraction in these systems has been shown to proceed through as many as three competing pathways over a wide range of conditions. Despite this added complexity, the favorable physicochemical characteristics …