Physical Sciences and Mathematics | Open Access Articles

Dendrimer-Encapsulated Nanoparticle Precursors To Supported Platinum Catalysts, Huifang Lang, R Alan May, Brianna L. Iversen, Bert D. Chandler

Chemistry Faculty Research

In this contribution, we report the successful preparation of supported metal catalysts using dendrimer-encapsulated Pt nanoparticles as metal precursors. Polyamidoamine (PAMAM) dendrimers were first used to template and stabilize Pt nanoparticles prepared in solution. These dendrimer-encapsulated nanoparticles were then deposited onto a commercial high surface area silica support and thermally activated to remove the organic dendrimer. The resulting materials are active oxidation and hydrogenation catalysts. The effects of catalyst preparation and activation on activity for toluene hydrogenation and CO oxidation catalysis are discussed.

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Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics - Phase Three, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The proposed work will combine chemical kinetics and hydrodynamics in target and test-loop lead-bismuth eutectic (LBE) systems to model system corrosion effects. This approach will result in a predicative tool that can be validated with corrosion test data, used to systematically design tests and interpret the results, and provide guidance for optimization in LBE system designs. The task includes two subtasks. The first subtask is to try to develop the necessary predictive tools to be able to predict the levels of oxygen and corrosion products close to the boundary layer through the use of Computational Fluid Dynamics (CFD) modeling. The …

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Particle Growth In Urban And Industrial Plumes In Texas, Charles A. Brock, Michael Trainer, Thomas B. Ryerson, J. Andrew Neuman, David D. Parrish, John S. Holloway, Dennis K. Nicks, Gregory J. Frost, Gerhard Hübler, Fred C. Fehsenfeld, J. Charles Wilson, J. Michael Reeves, Bernard G. Lafleur, Henrike Hilbert, Elliot L. Atlas, Stephen G. Donnelly Ph.D., Sue M. Schauffler, Verity R. Stroud, Christine Wiedinmyer

Chemistry Faculty Publications

Particle size distributions and gas-phase particle precursors and tracer species were measured aboard an aircraft in the plumes downwind from industrial and urban sources in the vicinity of Houston, TX during the daytime in late August and early September 2000. Plumes originating from the Parish gas-fired and coal-fired power plant, petrochemical industries along the Houston ship channel, the petrochemical facilities near the Gulf coast, and the urban center of Houston were studied. Most of the particle mass flux advected downwind of Houston came from the industries and electrical utilities at the periphery of the city rather than from sources in …

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Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor

Turkish Journal of Chemistry

The kinetics of oxidation of pyridylmethylsulphinylbenzimidazole [PMSB] by Ce(IV) in an aqueous perchloric acid medium at a constant ionic strength of 1.50 mol dm^{-3} were studied spectrophotometrically. The reaction showed first order kinetics with respect to Ce(IV) concentration and an apparent less than unit order dependence in [PMSB] and a zero order in [H^+]. The initial addition of products has no significant effect on the rate of the reaction. A possible mechanism is proposed here. The reaction constants involved in the mechanism have been computed. There is good agreement between the observed and calculated rate constants under different experimental conditions. …

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Application Of Ibx Method For The Synthesis Of Ketones From Carboxylic Acids, H. R. Ferhat Karabulut, Mesut Kaçan, Hasan Özyildirim

Turkish Journal of Chemistry

Methoxy phenyl propionic acid and some derivatives are converted to ketones using a new method. All classical methods to obtain ketones from carboxylic acids via acid halide consistently gave very low yields and regularly generated intermolecular cyclisation products or polymeric materials. However, high ketones yields are obtained by using the new IBX method.

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Kinetics And Mechanism Of Oxidation Of L-Isoleucine And L-Ornithine Hydrochloride By Sodium N-Bromobenzenesulphonamide In Perchloric Acid Medium, Hemmige S. Yathirajan, Chapuradoddi R. Raju, Kikkeri N. Mohana, Sheena Shashikanth, Padmarajaiah Nagaraja

Turkish Journal of Chemistry

Kinetic studies of the oxidation of L-isoleucine (ISL) and L-ornithine hydrochloride (ORH) by sodium N-bromobenzenesulphonamide (bromamine-B or BAB) were studied in aqueous perchloric acid medium. The rate shows first-order dependence on both [BAB]_0 and [amino acid]_0 and inverse first-order dependence on [H^+] for ISL and first-order dependence on [H^+] for ORH. The rate of reaction decreased with decreases in the dielectric constant of the medium. The addition of benzenesulphonamide (BSA), which is one of the reaction products, had no significant effect on the reaction rate. The rate remained unchanged with the variation in the ionic strength of the medium for …

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Full-Text Articles in Physical Sciences and Mathematics

Dendrimer-Encapsulated Nanoparticle Precursors To Supported Platinum Catalysts, Huifang Lang, R Alan May, Brianna L. Iversen, Bert D. Chandler

Chemistry Faculty Research

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics - Phase Three, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

Chemistry Faculty Publications

Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor

Turkish Journal of Chemistry

Application Of Ibx Method For The Synthesis Of Ketones From Carboxylic Acids, H. R. Ferhat Karabulut, Mesut Kaçan, Hasan Özyildirim

Turkish Journal of Chemistry

Kinetics And Mechanism Of Oxidation Of L-Isoleucine And L-Ornithine Hydrochloride By Sodium N-Bromobenzenesulphonamide In Perchloric Acid Medium, Hemmige S. Yathirajan, Chapuradoddi R. Raju, Kikkeri N. Mohana, Sheena Shashikanth, Padmarajaiah Nagaraja

Turkish Journal of Chemistry