Inorganic Chemistry Commons^™

Synthesis And Characterization Of Extended Solids Containing Nano-Sized Transition Metal Oxide Lattices, Matthew Williams

All Dissertations

In this research, focus has been placed on the study of magnetic anomalies due to geometric frustration of magnetic ions. The goal of the study presented in this dissertation was to synthesize pseudo&ndashlow&ndashdimensional (PLD) compounds, those structures showing zero (dot), one (chain), and two (sheet) dimensional lattices observed in extended (3D) host frameworks with enhanced anisotropic physical properties, in an attempt to elucidate some structure&ndashproperty correlations arising from magnetic spin confinement. The scope of this research involved 1) exploratory synthesis of novel, low&ndashdimensional transition metal oxide lattices, specifically Mn and V, embedded in non&ndashmagnetic oxyanion frameworks, either Ge, P, or …

Resorbable Polymer-Hydroxyapatite Composites For Bone Trauma Treatment: Synthesis And Properties, Troy E. Wiegand

Department of Chemistry: Dissertations, Theses, and Student Research

Contemporary therapies for hard tissue replacement involve allographs, where the donor and recipient are of the same species, or the use of xenogenic transplants.  Intraspecies materials are often in short supply and interspecies materials are subject to immunological barriers such as disease and tissue rejection.  Synthetic composites are unencumbered by these limitations.  Poly lactic acid (PLLA) and its copolymers have been used in medicine due to their ability to be resorbed by the body without adverse effects.  PLLA’s are currently most commonly used in resorbable sutures and gauzes, but there is increasing interest in using them in conjunction with hydroxyapatite …

Dna-Inks For 3-D Printing: Dna Composites For The Rapid Prototyping Of Scaffold In Bioengineering Applications, Jimena I. Aguirre^, Ryan B. Wicker, Mireya A. Perez, Juan C. Noveron*, Juan M. Sanchez

COURI Symposium Abstracts, Spring 2011

Rapid-prototyping has become an incredible technique that manufactures three-dimensional objects with intricate complexity down to 8µm of resolution. We are developing materials that can be used by rapid-prototyping instruments to make scaffolds for bioengineering applications. Our molecular design involves the polymerization of a  (vinylbenzyl)trimethyl-ammonium chloride and DNA solution. Upon UV illumination, the composite polymerizes and forms DNA-hybrid materials.  The end result becomes a ductile transparent material with a thin cross-section. The synthesis, characterization and application of rapid prototyping will be described. Scanning Electron Microscopy (SEM), Light Scattering Detector (LDS), Nuclear Magnetic Resonance (NMR), and Infrared Spectroscopy indicate the structure, characteristics, …

Rudimentary G-Quadruplex-Based Telomere Capping In Saccharomyces Cerevisiae, J. S. Smith, Q. Chen, Liliya A. Yatsunyk, John Michael Nicoludis , '12, M. S. Garcia, R. Kranaster, S. Balasubramanian, D. Monchaud, M.-P. Teulade-Fichou, L. Abramowitz, D. C. Schultz, F. B. Johnson

Chemistry & Biochemistry Faculty Works

Telomere capping conceals chromosome ends from exonucleases and checkpoints, but the full range of capping mechanisms is not well defined. Telomeres have the potential to form G-quadruplex (G4) DNA, although evidence for telomere G4 DNA function in vivo is limited. In budding yeast, capping requires the Cdc13 protein and is lost at nonpermissive temperatures in cdc13-1 mutants. Here, we use several independent G4 DNA-stabilizing treatments to suppress cdc13-1 capping defects. These include overexpression of three different G4 DNA binding proteins, loss of the G4 DNA unwinding helicase Sgs1, or treatment with small molecule G4 DNA ligands. In vitro, we show …

A Sodium Salt Of The Dimer Of Boronoterephthalic Acid Anhydride, Scott Simmons, Albert Fratini, Vladimir Benin

Chemistry Faculty Publications

The title compound, sodium bis­(6-carb­oxy-1-hy­droxy-3-oxo-1,3-dihydro-2,1-benzoxaborol-1-yl)oxidanium, Na+·C16H15B2O13-, was prepared in two steps from 2-bromo-p-xylene. Its crystal structure was determined at 140 K and has triclinic (P) symmetry. The compound presents a unique structural motif, including two units of the cyclic anhydride of boronoterephthalic acid, joined by a protonated, and thereby trivalent, oxonium center. Association in the crystal is realized by complementary hydrogen bonding of the carboxyl groups, as well as by coordination of the sodium cations to the oxygen centers on the five-membered rings.

Theoretical Investigation Of A Reported Antibiotic From The 'Miracle Tree' Moringa Oleifera, Michael Horwath, Vladimir Benin

Chemistry Faculty Publications

Moringa oleifera, sometimes called the “Miracle Tree,” has received international attention for its potential to improve health in impoverished tropical areas. In addition to high vitamin content in the leaves and pods, the tree contains compounds with antioxidant and antibacterial properties. This study focused on the theoretical investigation of the suggested structure of one antibacterial compound, “pterygospermin,” whose existence was proposed after some studies of the roots of M. oleifera. The structure of pterygospermin was first proposed by a research group working in the 1950s, but later studies have not found evidence of this compound and have instead …

Computational Investigation Of The Bioactive Selenium Compounds Ebselen And Selenious Acid, Sonia Antony

Chemistry & Biochemistry Theses & Dissertations

Selenium, a toxic element, is required in trace quantities for the proper functioning of biological systems. The experimental mechanistic study of the reactions of ebselen and selenious acid is difficult due to complexity of the reaction mixtures and the presence of short-lived intermediates. Computational modeling of the reactivity of these species can give us an insight into their mechanisms, but the process is complicated by proton exchanges associated with the mechanistic steps. In gas phase modeling, this may be corrected to a certain level using the solvent assisted proton exchange (SAPE) method. SAPE is a modeling technique that mimics solvent …

A Three Dimensional Green's Function Solution Technique For The Transport Of Heavy Ions In Laboratory And Space, Candice Rockell Gerstner

Mathematics & Statistics Theses & Dissertations

In the future, astronauts will be sent into space for longer durations of time compared to previous missions. The increased risk of exposure to ionizing radiation, such as Galactic Cosmic Rays and Solar Particle Events, is of great concern. Consequently, steps must be taken to ensure astronaut safety by providing adequate shielding. The shielding and exposure of space travelers is controlled by the transport properties of the radiation through the spacecraft, its onboard systems and the bodies of the individuals themselves. Meeting the challenge of future space programs will therefore require accurate and efficient methods for performing radiation transport calculations …

Metal Carbonyl Catalysts For The Transformation Of Silicon Hydrides To Siloxanes In The Presence Of Dmf, Eduardo Cervantes^, Renzo Arias Ugarte, Hemant K. Sharma, Keith H. Pannell*

COURI Symposium Abstracts, Spring 2011

It has recently been reported that, upon photochemical irradiation, tertiary silanes (R₃SiH) react with DMF to form disiloxanes (R₃Si-O-SiR₃) and Me₃N, using the transition metal alkyl complex (η⁵-C₅H₅)Fe(CO)₂Me as a catalyst. Intermediates of the type R₃SiOCH₂NMe₂ were proposed as the important first step via a hydrosilylation reaction but no evidence was obtained for this suggestion. By changing the catalyst to Mo(CO)₆ we have now observed that not only do we form the expected  disiloxanes, but for the first …

Synthesis Of N-Acetyl And C-Tert-Butyl Natural Amino Acid Substrates That Mimic Residues Of Polypeptides And Their Reactivity With [Feiv(O)(N4py)]2+: Kinetic And Mechanistic Investigations, Ashley Ann Campanali

Wayne State University Dissertations

This dissertation is divided into two chapters, the first chapter includes an introduction to reactive oxygen species and their reactions with proteins. The introduction also covers metal-based oxidants, including both heme and non-heme enzymes that activate dioxygen as well as complexes that mimic these enzymes. The work discussed in chapter one concerns the synthesis of amino acid substrates that mimic amino acid residues. Substrates synthesized were derived from Gln, Asn, Ile, Cys and Tyr. Once synthesized, these substrates were reacted with [FeIV(O)(N4Py)]2+ under pseudo-first order conditions. The mechanisms for the reactions of the most reactive substrates were investigated. Electron-transfer proton-transfer …

Application Of Niobium Enriched Ormosils As Thermally Stable Coatings For Aerospace Aluminium Coatings, P.C. Rajath Varma, Mohamed Oubaha, Pradeepan Periyat, Colette Mcdonagh, Brendan Duffy

Articles

The aim of this experimental research is to study the ability of niobium rich sol-gel coatings to withstand thermal stress, while remaining impermeable to corrosive agents for the protection of aerospace alloys. The coating material is developed via polymeric sol-gel synthesis employing 3-(trimethoxysilyl)propylmethacrylate (MAPTMS) and niobium ethoxide precursors as a source of silicon and niobium, respectively. The beneficial effect of niobium inclusion within coating was characterised spectroscopically, calorimetrically and electrochemically. The thermal cycling effects of the coating were studied using microscopic and accelerated test methods. Electrochemical tests showed that corrosion current of the material was 2 orders lower in magnitude …

Crystallisation And Phase Transition Characteristics Of Sol-Gel-Synthesized Zinc Titanates, Suresh Pillai, Michael Seery, Nicholas Nolan

Articles

No abstract provided.

Supramolecular Organization Of Nanoparticles, Brenda M. Porta Linnell

Open Access Theses & Dissertations

The study of supramolecular structures with nano-architectures has become an active area of research in recent years. They have the potential to generate functional materials with applications in medicine and emerging technologies. In this dissertation, the supramolecular organization of gold nanoparticles (AuNP) and other nano-scale structures such as discrete styrene-based polymers was investigated. The synthesis and characterization of metal-mediated AuNPs systems using pendant ligands on the AuNP such as 11-diethylenetriamine-undecane-1-thiol, 11-Mercapto-undecanoic acid [2-(2-amino-ethylamino)-ethyl]-amide, Bis(11-oxo-nicotinic acid, undecine)disulfide, and 11-mercaptoundecanoic acid, and using Cu(II) to mediate the formation of supramolecular AuNP systems with sizes of 200 nm ¡V 3 fÃ?m, are …

Developing Dimetal Paddlewheel Complexes For Catalytic Applications, Margaret E. Napier

Legacy Theses & Dissertations (2009 - 2024)

Although there are countless examples of rhodium-catalyzed organic reactions in the chemical literature, the field continues to develop at a steady pace, as focus shifts taking advantage of economy of resources while maintaining efficiency of the catalytic reactions. The work presented is separated into three chapters, with each describing a specific approach to the development of new materials which can provide either a direct economy of resources and reagents or can be used for heterogenization of catalytic systems.

Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) with different shapes and disk-shaped Ag NP pairs with varying interparticle distance is studied using dark-field optical microscopy and spectroscopy (DFOMS). Disk-, square-, and triangular-shaped Ag NPs were fabricated on indium tin oxide-coated glass substrates by electron beam lithography. The LSPR spectra collected from single Ag NPs within 5×5 arrays using DFOMS exhibited pronounced redshifts as the NP shape changed from disk to square and to triangular. The shape-dependent experimental LSPR spectra are in good agreement with simulations using the discrete dipole approximation model, although there are small deviations in the …

Fabrication And Catalytic Property Of Cerium Oxide Nanomaterials, Keren Jiang

Department of Chemistry: Dissertations, Theses, and Student Research

Cerium oxide, or ceria (CeO_x: x = 1.5 to 2), has been widely used as a heterogeneous catalyst. Ceria has several properties make it high catalytic active: the fluctuating valence of cerium, the high oxygen storage capacity and high oxygen mobility in the nonstoichiometric ceria. With the high abundance of cerium on earth crust, ceria is a highly effective alternative of the noble metal catalysts. Research has been focused on designing nanostructured ceria and ceria related materials in recent years. The catalytic activity of ceria can be enhanced by the nanoscale effect which can be applied for various …

Synthesis, Assembly, And Characterization Of Monolayer-Protected Gold Nanoparticle Films For Protein Monolayer Electrochemistry,, Tran T. Doan, Michael H. Freeman, Adrienne R. Schmidt, Natalie T. Nguyen, Michael C. Leopold

Chemistry Faculty Publications

Colloidal gold nanoparticles protected with alkanethiolate ligands called monolayer protected gold clusters (MPCs) are synthesized and subsequently incorporated into film assemblies that serve as adsorption platforms for protein monolayer electrochemistry (PME). PME is utilized as the model system for studying electrochemical properties of redox proteins by confining them to an adsorption platform at a modified electrode, which also serves as a redox partner for electron transfer (ET) reactions. Studies have shown that gold nanoparticle film assemblies of this nature provide for a more homogeneous protein adsorption environment and promote ET without distance dependence compared to the more traditional systems modified …

Crystal Engineering Of Pharmaceutical Cocrystals, Sreya Mukherjee

USF Tampa Graduate Theses and Dissertations

Pharmaceutical cocrystals use principles of crystal engineering for the design of crystalline forms of drugs and can improve their solubility, bioavailability, stability and other important properties without changing the efficacy of the drug. Herein reported are pharmaceutical cocrystals of two API's, caffeine and Pentoxifylline.

Research has indicated that caffeine has the ability to reverse AB; plaque deposition in the brain (believed to be the primary cause of Alzheimer's pathogenesis) and thus revert memory and improve cognitive impairment. But owing to the fast absorption rate and short half life, a controlled release formulation of caffeine would be clinically beneficial. Thus, novel …

Preliminary Analysis Of Thermally Induced Condensed Phase Electron Transfer Reactions Of Cadmium Chloride And Lead Chloride With Electropositive Metals, Vamshi Addaguduru

Student Theses and Dissertations

The thermal stabilities and thermal decomposition for the metal halides, cadmium chloride and lead chloride with electropositive metals like Mn, Zn, Cr and Fe were studied at elevated temperatures using thermal analysis techniques, thermogravimetry and differential thermal analysis using TG/DTA apparatus. The reactions of cadmium chloride and lead chloride with electropositive metals were conducted in Cu pans and found that Zinc metal may show a reaction with both CdCl2 and PbCl2; Manganese may not react with CdCl2 and may react with PbCl2; iron may react with CdCl2 but not with PbCl2 and chromium may not react with both the metal …

Preliminary Analysis Of Thermally Induced Condensed Phase Electron Transfer Reactions Of Nickel Chloride With Electropositive Metals, Rajeshwari Devi Kamineni

Student Theses and Dissertations

The thermal decomposition, dehydration and thermal stability studies of nickel (II) chloride hexahydrate and nickel (II) chloride hexahydrate with electropositive metals cobalt, cadmium, iron, chromium, zinc and manganese have been investigated by non-isothermal method using TG/DTA under argon gas flow. The thermal decomposition and dehydration reactions reveal that there is loss of six water molecules from NiCl2.6H2O. A catalytic action of Cu from Cu pans in thermal decomposition reactions of NiCl2.6H2O and NiCl2.6H2O with electropositive metals was also observed. The change in enthalpy (∆H) of the Fe and Co with NiCl2.6H2O was calculated from the TG/DTA plot onset temperature, using …