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Articles 1 - 30 of 32
Full-Text Articles in Inorganic Chemistry
Improved Synthesis Of Pincer Ligand Precursor, And Synthesis And Structural Characterization Of Terphenyl Scaffolded S–C–S Palladium Pincer Complex., Paul Schroder, Thomas Spilker, Wilson Luu, James Updegraff, Man Lung Kwan, Paul Challen, John Protasiewicz
Improved Synthesis Of Pincer Ligand Precursor, And Synthesis And Structural Characterization Of Terphenyl Scaffolded S–C–S Palladium Pincer Complex., Paul Schroder, Thomas Spilker, Wilson Luu, James Updegraff, Man Lung Kwan, Paul Challen, John Protasiewicz
Man Lung Desmond Kwan
An easier and more expedient synthesis of 2,6-(BrCH2C6H4)2-4-I-C6H3 (2) is reported. This material allowed easy synthesis of the new pincer ligand precursor 2,6-(4-CH3C6H4SCH2C6H4)2-4-I-C6H3 (3) in 87% yield. Compound 3 reacts with Pd2(dba)3 to give the new palladium pincer complex 4. Compound 4 has been fully characterized, including structural characterization by single crystal X-ray diffraction methods. The results of the crystallographic work on 4 reveal a twisted type pincer complex not unlike related terphenyl pincer complexes.
Solid State And Solution Dynamics Of Pyridine Based Tetraaza- Macrocyclic Lanthanide Chelates Possessing Phosphonate Ligating Functionality (Ln-Pctmb): Effect On Relaxometry And Optical Properties, Garry Kiefer, Mark Woods
Solid State And Solution Dynamics Of Pyridine Based Tetraaza- Macrocyclic Lanthanide Chelates Possessing Phosphonate Ligating Functionality (Ln-Pctmb): Effect On Relaxometry And Optical Properties, Garry Kiefer, Mark Woods
Chemistry Faculty Publications and Presentations
The macrocyclic ligand 3,6,9-tris(methylenebutyl phosphonic acid)-3,6,9−15-tetraazabicyclo [9.3.1]pentadeca-1(15),11,13-triene (PCTMB) was synthesized and complexes of Eu3+, Tb3+, and Gd3+ studied by X-ray crystallography, luminescence, and relaxometry. In the crystal these complexes are dimeric and possess 8-coordinate Ln3+ centers that are linked by bridging phosphonates. The rigidity introduced by the pyridyl nucleus forces the EuPCTMB and TbPCTMB to adopt a twisted snub disphenoid (TSD) coordination geometry. Examination of the 5D0 → 7F0 luminescent transition of EuPCTMB in the solid state confirmed the existence of a single distinct Eu3+ coordination environment, whereas two …
Manganese Oxide Mineral Phases Produced At Room Temperature Under Acidic Conditions Investigated With Xrd, Tem, Sem, Eds, And Bet, Nancy R. Birkner
Manganese Oxide Mineral Phases Produced At Room Temperature Under Acidic Conditions Investigated With Xrd, Tem, Sem, Eds, And Bet, Nancy R. Birkner
UNLV Theses, Dissertations, Professional Papers, and Capstones
This thesis concerns characterization of synthetic manganese oxides belonging to mineral phases known as Birnessite and Cryptomelane. Presented here are the results of an experiment designed to examine the influence of sodium, potassium, chloride, and sulfate ions on the reduction of potassium permanganate under acidic conditions at room temperature to produce Birnessite and Cryptomelane. The experiments used KMnO4 as the source of Mn and the resulting Birnessite and Cryptomelane precipitates were washed with 18 Mn/cm NANOpure water at the end of syntheses. Several state-of-the-art solid state techniques were used to characterize the Mn-based oxide mineral phases. Based on the literature …
Improved Synthesis Of Pincer Ligand Precursor, And Synthesis And Structural Characterization Of Terphenyl Scaffolded S–C–S Palladium Pincer Complex., Paul Schroder, Thomas Spilker, Wilson Luu, James Updegraff, Man Lung Kwan, Paul Challen, John Protasiewicz
Improved Synthesis Of Pincer Ligand Precursor, And Synthesis And Structural Characterization Of Terphenyl Scaffolded S–C–S Palladium Pincer Complex., Paul Schroder, Thomas Spilker, Wilson Luu, James Updegraff, Man Lung Kwan, Paul Challen, John Protasiewicz
Paul R. Challen
An easier and more expedient synthesis of 2,6-(BrCH2C6H4)2-4-I-C6H3 (2) is reported. This material allowed easy synthesis of the new pincer ligand precursor 2,6-(4-CH3C6H4SCH2C6H4)2-4-I-C6H3 (3) in 87% yield. Compound 3 reacts with Pd2(dba)3 to give the new palladium pincer complex 4. Compound 4 has been fully characterized, including structural characterization by single crystal X-ray diffraction methods. The results of the crystallographic work on 4 reveal a twisted type pincer complex not unlike related terphenyl pincer complexes.
Distance Dependence Of Electron Transfer Kinetics For Azurin Protein Adsorbed To Monolayer Protected Nanoparticle Film Assemblies, Morgan Lynn Vargo, Chris P. Gulka, John K. Gerig, Christopher M. Manieri, Jonathan D. Dattelbaum, Carolyn B. Marks, Nathaniel T. Lawrence, Matthew L. Trawick, Michael C. Leopold
Distance Dependence Of Electron Transfer Kinetics For Azurin Protein Adsorbed To Monolayer Protected Nanoparticle Film Assemblies, Morgan Lynn Vargo, Chris P. Gulka, John K. Gerig, Christopher M. Manieri, Jonathan D. Dattelbaum, Carolyn B. Marks, Nathaniel T. Lawrence, Matthew L. Trawick, Michael C. Leopold
Chemistry Faculty Publications
The distance dependence and kinetics of the heterogeneous electron transfer (ET) reaction for the redox protein azurin adsorbed to an electrode modified with a gold nanoparticle film are investigated using cyclic voltammetry. The nanoparticle films are comprised of nonaqueous nanoparticles, known as monolayer-protected clusters (MPCs), which are covalently networked with dithiol linkers. The MPC film assembly serves as an alternative adsorption platform to the traditional alkanethiolate self-assembled monolayer (SAM) modified electrodes that are commonly employed to study the ET kinetics of immobilized redox proteins, a strategy known as protein monolayer electrochemistry. Voltammetric analysis of the ET kinetics for azurin adsorbed …
Synthesis And Characterization Of Magnetic Solids Containing Periodic Arrays Of Transition Metal Oxide Nanostructures, Wendy Queen
Synthesis And Characterization Of Magnetic Solids Containing Periodic Arrays Of Transition Metal Oxide Nanostructures, Wendy Queen
All Dissertations
The ultimate goal of the research presented in this dissertation was to explore new systems containing low–dimensional magnetic nanostructures in hopes of finding new extended solids exhibiting novel magnetic properties due to the confined magnetic lattices. The scope of this research is threefold: 1) to explore new solids containing low–dimensional magnetic nanostructures in the A–M–X–O system, where A is an alkali or alkalinendash;earth metal cation, M is a first–row transition metal cation, and X is P, As, or V, 2) to characterize these new materials and, through chemical substitution, fine tune (and optimize) magnetic and electronic properties of solids that …
Synthesis Of Complex Fluorides For Optical Applications, Seth Stepleton
Synthesis Of Complex Fluorides For Optical Applications, Seth Stepleton
All Dissertations
Large single crystals of alkali metal fluorides are desirable for many reasons. Fluoride laser crystals have a wide transmission range and on account of their low phonon energies, many efficient laser emissions have been obtained from 285 nm to 4.34 µm.1,2 Inorganic fluoride single crystals feature large bandgaps, very wide optical transmittance ranges from vacuum-ultraviolet (VUV) to mid-IR wavelength regions, lower refractive indices than those of oxides, and typically lower phonon energies (which drastically reduce multiphonon relaxation rates of rare earth ions).3
The main goal of this work was to investigate the hydrothermal synthesis of alkali metal fluorides. Melt techniques …
Understanding The Antioxidant Mechanism Of Inorganic Selenium, Oxo- Sulfur, And Polyphenol Compounds, And The Biological Implications Of Functionalized Nanoparticles, Ria Ramoutar
All Dissertations
Inorganic selenium, oxo-sulfur, and polyphenol compounds are found in foods and dietary supplements, and are recognized for their nutritional benefits and their potential to treat or prevent diseases caused by oxidative stress. In our experiments to determine the effects of inorganic selenium compounds on iron-mediated DNA damage, Na2SeO33 and SeO2 exhibit antioxidant and pro-oxidant activities depending on concentrations of both the compound and hydrogen peroxide. Additional experiments demonstrate that iron coordination is a novel mechanism responsible for the observed activities. In similar experiments, oxo-sulfur compounds prevent Cu+/ H2O2-mediated DNA damage significantly …
Hydrothermal Crystal Growth Of Tetravalent And Pentavalent Metal Oxides, James Mann
Hydrothermal Crystal Growth Of Tetravalent And Pentavalent Metal Oxides, James Mann
All Dissertations
Over the past two hundred years synthetic growth of crystals has become vital to the technological advancement of our society. A variety of crystal growth techniques have been developed during this time, with each having its own nuances. These differences have enabled the growth of a wide spectrum of crystalline materials that can be used for many applications which include solid state lasers, semiconductors, and communication devices. Despite these techniques there are entire classes of materials which have thus far proved quite difficult to prepare as single crystals. In particular, crystal growth of the tetravalent and pentavalent metal oxides has …
Synthesis And Characterization Of Bis-Phosphine Complexes With Transition Metals, Alicia L. Mcdaniel
Synthesis And Characterization Of Bis-Phosphine Complexes With Transition Metals, Alicia L. Mcdaniel
Masters Theses & Specialist Projects
Extractants and extraction methodologies play a vital role in many industrial processes, from the concentration of precious metals from ores to the separation of longlived nuclei from radioactive waste as well as the removal of heavy metals from soils and water for remediation. The vast majority of extractants rely on the use of nitrogen, oxygen, sulfur or selenium as Lewis base donor atoms to form coordination complexes with the metal ions of interest. These extractants often make use of the chelate effect and/or the macrocyclic effect in order to form stable complexes. Some of the best known types of chelate …
The Spectroelectrochemical, Magnetic, And Structural Characterization Of Reduced Hexaazatriphenylenehexacarbonitrile, Hat(Cn)6., Joseph Gallegos, Anthony Francis, Nathan Ockwig, Paul Rasmussen, Raphael Raptis, Paul Challen, Issouf Ouedraogo
The Spectroelectrochemical, Magnetic, And Structural Characterization Of Reduced Hexaazatriphenylenehexacarbonitrile, Hat(Cn)6., Joseph Gallegos, Anthony Francis, Nathan Ockwig, Paul Rasmussen, Raphael Raptis, Paul Challen, Issouf Ouedraogo
Paul R. Challen
The cyanoazacarbon, hexaazatriphenylenehexacarbonitrile, or HAT(CN)6, is readily reduced and the spectroelectrochemical properties associated with the multiple reductions are described. The singly reduced radical monoanion forms stable salts and we report the crystal structure and magnetic properties for the tetrabutylammonium salt. [Tetra-n-butylammonium] [HAT(CN)6] behaves ferromagnetically below 3K and follows Curie Law behavior at higher temperatures after correction for Pauli-type susceptibility. The room temperature conductivity of the powdered salt is 3.8×10−8S/cm. The crystal structure shows closely bound pairs of radical anions with slip-stacking of these pairs to form a staircase, features that elucidate the observed properties. Thin films of HAT(CN)6 were found …
The Synthesis And Characterization Of Novel Microporous Hybrid Organic/Inorganic Materials, Kelly Whitenack
The Synthesis And Characterization Of Novel Microporous Hybrid Organic/Inorganic Materials, Kelly Whitenack
Honors Capstone Projects - All
Inorganic chemistry is essential to the formulation and improvement of modern materials such as catalysts, semiconductors, optical devices, super conductors, and advanced ceramic materials.1 New areas of inorganic chemistry are constantly being explored and new and often unusual inorganic compounds are constantly being synthesized and identified.1 Recently the field of inorganic chemistry has witnessed the synthesis and characterization of microporous metal organic framework compounds (MOFs). Microporous organic/inorganic materials have a wide range of physical properties as well as applications. The physical properties and applications drive the investigation into the synthesis and discovery of new and useful hybrid MOF …
Synthesis Of Ionic Liquid Monomers Using Fluorinated Sulfonyl Imide Anions And The 1,3-Dialkylimidazolium Cation, Thomas Hickman
Synthesis Of Ionic Liquid Monomers Using Fluorinated Sulfonyl Imide Anions And The 1,3-Dialkylimidazolium Cation, Thomas Hickman
All Dissertations
With their unique material and solvent properties, ionic liquids have seen an amazing, exponential increase in interest. After a brief introduction of select areas of interest for these compounds, this thesis mainly focuses on the development of novel polyfunctional ionic liquids and polymeric ionic liquids.
One of the preferred anions for ionic liquids is the bis((trifluoromethyl)sulfonyl) imide anion, first introduced by our group in 1982. It shows excellent thermal stability and the desired resonance delocalization of a negative charge for ionic liquids. A series of monofunctional, difunctional, and multi-functional bis(perfluoroalkylsufonyl)imides, along with 1,3-dialkylimidazolium cations were prepared by direct methylation of …
Metallophilic Interactions In Closed-Shell Metal-Metal Bonded Luminescent Systems And Their Tunability For Excited State Energy Transfer, Howard H. Patterson
Metallophilic Interactions In Closed-Shell Metal-Metal Bonded Luminescent Systems And Their Tunability For Excited State Energy Transfer, Howard H. Patterson
University of Maine Office of Research Administration: Grant Reports
Howard Patterson, University of Maine, is supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program for photochemical studies of metal-metal bonded excimers and exciplexes. In solution or in the solid state, dicyanoaurate(I) and dicyanoargentate(I) ions oligomerize. The oligomers show complex photochemistry, including luminescence caused by metallophilic interactions. These systems can be tuned over 18,000 wavenumbers by doping or by adding various donor ions. This research project will look in detail at lifetime and time-resolved studies, vibrational analysis by Raman scattering and infrared, structural studies by x-ray and neutron diffraction, and theoretical analyses. The research will provide insight into metallophilic interactions …
Polyelectrolyte-Linked Film Assemblies Of Nanoparticles And Nanoshells: Growth, Stability, And Optical Properties, Anne A. Galyean, Justin Malinowski, Robert W. Day, Kevin W. Kittredge, Michael C. Leopold
Polyelectrolyte-Linked Film Assemblies Of Nanoparticles And Nanoshells: Growth, Stability, And Optical Properties, Anne A. Galyean, Justin Malinowski, Robert W. Day, Kevin W. Kittredge, Michael C. Leopold
Chemistry Faculty Publications
Multi-layer films of nanoparticles and nanoshells featuring various polymeric linkage molecules have been assembled and their optical properties characterized. The growth dynamics, including molecular weight effects, and stability of the various nanoparticle film constructions, using both single polymer as well as combinations of alternating charge polyelectrolytes as linking mechanisms, are presented. The polymeric linkers studied include poly-L-lysine, poly-L-arginine, poly(allylamine hydrochloride), and polyamidoamine dendrimers. Significantly air stable films were achieved with the use of multi-layered polymeric bridges between the nanoparticles and nanoshells. Optical sensitivity normally observed with these nanomaterials in solution was observed for their corresponding film geometries, with the nanoshell …
Synthesis And Evaluation Of Lanthanide Ion Dota-Tetraamide Complexes Bearing Peripheral Hydroxyl Groups, Azhar Pasha, Mai Lin, Gyula Tircso, Cynthia L. Rostollan, Mark Woods, Garry Kiefer, A. Dean Sherry, Xiankai Sun
Synthesis And Evaluation Of Lanthanide Ion Dota-Tetraamide Complexes Bearing Peripheral Hydroxyl Groups, Azhar Pasha, Mai Lin, Gyula Tircso, Cynthia L. Rostollan, Mark Woods, Garry Kiefer, A. Dean Sherry, Xiankai Sun
Chemistry Faculty Publications and Presentations
The use of lanthanide-based contrast agents for magnetic resonance imaging has become an integral component of this important diagnostic modality. These inert chelates typically possess high thermodynamic stability constants that serve as a predictor for in vivo stability and low toxicity. Recently, a new class of contrast agents was reported having a significantly lower degree of thermodynamic stability while exhibiting biodistribution profiles indicative of high stability under biological conditions. These observations are suggestive that the nature of contrast agent stability is also dependent upon the kinetics of complex dissociation, a feature of potential importance when contemplating the design of new …
Come For The Content, Stay For The Community, Hilary J. Eppley
Come For The Content, Stay For The Community, Hilary J. Eppley
Chemistry & Biochemistry Faculty publications
No abstract provided.
Silver Doped Perfluoropolyether-Urethane Coatings: Antibacterial Activity And Surface Analysis, Niall Stobie, Brendan Duffy, Steven Hinder, Patrick Mchale, Declan Mccormack
Silver Doped Perfluoropolyether-Urethane Coatings: Antibacterial Activity And Surface Analysis, Niall Stobie, Brendan Duffy, Steven Hinder, Patrick Mchale, Declan Mccormack
Articles
The colonisation of clinical and industrial surfaces with pathogenic microorganisms has prompted increased research into the development of effective antibacterial and antifouling coatings. There is evidence that implanted biomedical surfaces coated with metallic silver can be inactivated by hysiological fluids, thus reducing the bioactivity of the coating. In this work, we report the biofilm inhibition of Staphylococcus epidermidis using a roomtemperatureprocessedsilver dopedperfluoropolyether-urethane coating. The release of silver ions from these fluoropolymers over a six-day period inhibited bacterial encrustation – as observed by scanning electron microscopy (SEM). X-ray photoelectron spectroscopy (XPS) analysis indicated differences in carbon, fluorine and sodium surface composition …
One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat
One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat
Articles
No abstract provided.
Preparation Of Wo3 Nanoparticles Using Cetyl Trimethyl Ammonium Bromide Supermolecular Template, Nilofar Asim, S. Radiman, M.A. Bin Yarmo
Preparation Of Wo3 Nanoparticles Using Cetyl Trimethyl Ammonium Bromide Supermolecular Template, Nilofar Asim, S. Radiman, M.A. Bin Yarmo
Nilofar Asim
WO3 is one of the most interested metal oxides because of its application as catalysts, sensors, electrochromic devices, ceramic, solar cell, pigments and so on. More investigation is needed to find the good and low cost method for preparation of WO3 nanoparticles with uniform morphology and narrow distribution using a surfactant mediated method. Approach: In this study, the synthesis of WO3 nanoparticles was accomplished using a cationic surfactant (cetyl trimethyl ammonium bromide) as the organic supermolecular template and WCl6 and NH4 OH as the inorganic precursor and counter ion source, respectively. The effects of reaction temperature and surfactant concentration in …
(4-Hydroxy-2-Oxidobenzaldehyde Thiosemicarbazonato-Kappa O-3(2),N-1,S)(1, 10-Phenanthroline-Kappa N-2,N ')Zinc(Ii) Dimethyl Sulfoxide Disolvate Monohydrate, Tan Kong Wai, Ng C. H., Ng S. W., Maah M. J.
(4-Hydroxy-2-Oxidobenzaldehyde Thiosemicarbazonato-Kappa O-3(2),N-1,S)(1, 10-Phenanthroline-Kappa N-2,N ')Zinc(Ii) Dimethyl Sulfoxide Disolvate Monohydrate, Tan Kong Wai, Ng C. H., Ng S. W., Maah M. J.
Tan Kong Wai
The Zn-II atom in the title compound, [Zn(C8H7N3O2S)-(C12H8N2)]center dot 2C(2)H(6)OS center dot H2O, is N,N '-chelated by the N-heterocycle and N, O, S-chelated by the deprotonated Schiff base in a distorted square-pyramidal enviroment. Hydrogen bonds link the mononuclear molecule, the water and the dimethyl sulfoxide (DMSO) molecules into a linear chain motif. One DMSO molecule is disordered over two positions in respect of the S atom in an approximate 1:1 ratio.
Synthesis And Characterization Of Acetylenic Derivatives Of The Actinide Extractant (Aryl) N,N Di (Alkyl)Carbamoylmethylphosphine Oxide (Cmpo), Mario Ivan Baeza
Synthesis And Characterization Of Acetylenic Derivatives Of The Actinide Extractant (Aryl) N,N Di (Alkyl)Carbamoylmethylphosphine Oxide (Cmpo), Mario Ivan Baeza
Open Access Theses & Dissertations
We have used the reaction between the sodium salt of (diaryl)-N,N-di-(isobutyl)carbamoylmethylphosphine oxides {[Aryl)2P=O][iBu2NC=O]CH}-Na+ and chloromethylacetylenes to produce the first acetylenic derivatives of the carbamoylmethylphosphine oxide (CMPO) actinide extractants. The new compounds - CMPO-CH2C2H (1) {aryl = phenyl}, (2) {aryl = tBu-phenyl}; CMPO-CH2C2Me (3) {aryl = phenyl}; and CMPO-CH2C2CH2Cl (4) {aryl = phenyl}, (5) {aryl = tBu-phenyl} - have been characterized by spectroscopy (1H, 13C, 32P NMR) and also by single crystal X-ray diffraction. These new extractants lead the way to new derivatives aimed at using the materials as both optical and electrochemical actinide and other metal sensors.
Transition Metal Catalysts For Hydrodesulfurization Reactions Applied To Petroleum Industry, Brenda Torres
Transition Metal Catalysts For Hydrodesulfurization Reactions Applied To Petroleum Industry, Brenda Torres
Open Access Theses & Dissertations
Catalysis plays a fundamental role in petroleum refining and basic petrochemical industries creating new routes in the development of industrial processes. Moreover, catalysis has become indispensable to the solution of environmental pollution problems and therefore on public health. World wide concerns for preservation of the environment has motivated the development of "Green" catalyst based technologies, to achieve a better utilization of petroleum resources and demands for cleaner transportation fuels. These environmental concerns have led to increasingly drastic regulations on sulfur, nitrogen and aromatics content in fuels. Sulfur content in the motor and diesel fuels is continuously reduced by regulations to …
Silica Removal From Brine By Using Ion Exchange, Carlos R. Acevedo
Silica Removal From Brine By Using Ion Exchange, Carlos R. Acevedo
Open Access Theses & Dissertations
Local governments have been forced to look for additional water sources to satisfy the ever increasing demand for fresh water. Very often, the new water sources such as the underground water in continental territories have high salt content. Currently, reverse osmosis technology (RO) is one of the most common processes for water desalination. However, this process is limited by high silica and salt concentrations in water. At high concentrations silica clogs the membranes used in the RO process, reducing their life and increasing operational costs. In this study, quaternary ammonium resins and sulfonic acid resins were used to remove silica …
One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat
One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat
Articles
No abstract provided.
Effect Of Organic Chelates On The Performance Of Hybrid Sol–Gel Coated Aa2024-T3 Aluminium Alloys, Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy
Effect Of Organic Chelates On The Performance Of Hybrid Sol–Gel Coated Aa2024-T3 Aluminium Alloys, Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy
Articles
Sol–gels are organic–inorganic polymers formed by hydrolysis/condensation reactions of alkoxide precursors, primarily silanes, which have found applications as electronic, optical and protective coatings. These coatings possess important characteristics such as chemical stability, physical strength and scratch resistance. Further performance improvement is achieved through the incorporation of zirconium and titanium based nanoparticles, also formed through the sol–gel process. However due to the inherent difference in the reactivity of the precursors, the hydrolysis of each precursor must be carried out separately before being combined for final condensation. Zirconium precursors are commonly chelated using acetic acids, prior to hydrolysis, to lower the hydrolysis …
Influence Of Magnesium Nitrate On The Corrosion Performance Of Sol-Gel Coated Aa2024-T3 Aluminium Alloy, Rajath Varma, Brendan Duffy, John Cassidy
Influence Of Magnesium Nitrate On The Corrosion Performance Of Sol-Gel Coated Aa2024-T3 Aluminium Alloy, Rajath Varma, Brendan Duffy, John Cassidy
Articles
Traditional anti-corrosion technology has relied heavily on using reducible metal species, predominantly hexavalent chromium (Cr(VI)), for protecting reactive metal alloys such as aluminium which is extensively used in the aerospace sector. However, the impending changes in the use of Cr(VI) in Europe and the United States have forced aerospace manufacturers to examine alternative materials for protecting aluminium. One of the most promising alternatives being investigated are organosilane based sol-gels containing anticorrosion additives. In this work the anti-corrosion properties of magnesium (II) nitrate (Mg(NO3)2) as a inhibitor was investigated at different concentrations (0.1% - 1.0 wt %) in a methyltriethoxysilane (MTEOS) …
Preparation And Characterization Of Some Substituted Benzyl N-Nitrosocarbamates Containing An N-2-(Methylthio)Ethyl Or A Bis(2-Aminoethyl)Sulfide Functionality, Satya Venkata, Eric Shamo, Vladimir Benin
Preparation And Characterization Of Some Substituted Benzyl N-Nitrosocarbamates Containing An N-2-(Methylthio)Ethyl Or A Bis(2-Aminoethyl)Sulfide Functionality, Satya Venkata, Eric Shamo, Vladimir Benin
Chemistry Faculty Publications
The synthesis and characterization of some substituted benzyl N-nitrosocarbamates with an N-2-(methylthio)ethyl or a bis(2-aminoethyl)sulfide functionality is reported, as a part of a long-term goal to design and prepare novel photolabile structures that could be used as substances for controlled release of alkylating and/or crosslinking agents. The synthesis was accomplished by reaction of benzyl chloroformates with the corresponding amines, resulting in the preparation of carbamates. The latter were subsequently nitrosated, utilizing two different N-nitrosation methods, to yield the target structures.
Computational Modeling Studies Of The Structures And Properties Of Organotin(Iv) And Stannyl-Thioether Systems With Comparisons To X-Ray Crystallography, Michelle R. Stem Joseph
Computational Modeling Studies Of The Structures And Properties Of Organotin(Iv) And Stannyl-Thioether Systems With Comparisons To X-Ray Crystallography, Michelle R. Stem Joseph
Open Access Theses & Dissertations
Controlling the toxic effects of organotin(IV) compounds involves engineering the structure of the molecules to optimize their properties. Molecular engineering, coupled with improved capabilities to generate reliable computational optimization models (COMs), will enable researchers to have greater success at harnessing the highly specific cytotoxicity of organotins. For example, as the thion ligand phenyl groups were replaced with Cl atoms, the S-Sn intramolecularity was strengthened, the bond distance decreased, and the stannyl tetrahedral structure was deformed from its triphenyl conformation. With each substitution, conformation deformations lowered the damaging bioactivity levels of thion. Bonding various ligands to organotin(IV) compounds …
Bowl-Shaped Polyaromatic Hydrocarbons (Buckybowls) : Crystal Packing And Metal Binding Reactions, Alexander S. Filatov
Bowl-Shaped Polyaromatic Hydrocarbons (Buckybowls) : Crystal Packing And Metal Binding Reactions, Alexander S. Filatov
Legacy Theses & Dissertations (2009 - 2024)
This work is a part of a broad program in our laboratory dedicated to the investigation of a new class of non-planar polyaromatic hydrocarbons that map onto the surfaces of fullerenes (and referred to as buckybowls). It focuses on the preparation of buckybowls, their molecular and solid state structures, and reactivity in metal binding reactions. For the first time, the structures of all available buckybowls have been analyzed using X-ray diffraction data collected in the course of this work, as well as data previously obtained in our group or reported by others (and dearchived from the Cambridge Structural Database). Forces …