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Solid, activity inorganic

Most industrial catalysts are heterogeneous catalysts consisting of solid active components dispersed on the internal surface of an inorganic porous support. The active phases may consist of metals or oxides, and the support (also denoted the carrier) is typically composed of small oxidic structures with a surface area ranging from a few to several hundred m2/g. Catalysts for fixed bed reactors are typically produced as shaped pellets of mm to cm size or as monoliths with mm large gas channels. A catalyst may be useful for its activity referring to the rate at which it causes the reaction to approach chemical equilibrium, and for its selectivity which is a measure of the extent to which it accelerates the reaction to form the desired product when multiple products are possible [1],... [Pg.311]

An improved method for determining the AIT of solids has been described, and the effect of catalytically active inorganics on the reactivity and ignition temperature of solid fuels has been studied. Sodium carbonate markedly lowers the ignition temperatures of coal and coke [7], The volume of the vessel (traditionally a 200 ml flask) used to determine AIT has a significant effect on the results. For volumes of... [Pg.68]

Mechanochemically activated reactions between molecular solids and inorganic salts to obtain complexation and ion segregation in the solid state. [Pg.74]

Since 1946 there has been in process of development at Northwestern University a new method for the elucidation of structure in certain classes of catalytically active inorganic solids. This method depends upon an application of magnetic moment and molecular field theory to the oxidation state, coordination, and atomic environment of the active element. It is this development which is described below. [Pg.36]

The described bioaffinity separations demonstrate that polyacrylamide spacers aid the selective binding of highly complex and delicate biomacromolecules and their associates. Moreover, these solutes remain biologically active after desorption probably due to the high inertness and flexibility of the surrounding polymer chains fixed on the solid support. The unbound parts of serum usually show no loss of the activities of their constituents. Thus we evaluate the surface of inorganic supports coated with chemisorbed iV-hydroxyethyl polyacrylamide and its derivatives as being biocompatible. [Pg.172]

In addition to chemical reactions, the isokinetic relationship can be applied to various physical processes accompanied by enthalpy change. Correlations of this kind were found between enthalpies and entropies of solution (20, 83-92), vaporization (86, 91), sublimation (93, 94), desorption (95), and diffusion (96, 97) and between the two parameters characterizing the temperature dependence of thermochromic transitions (98). A kind of isokinetic relationship was claimed even for enthalpy and entropy of pure substances when relative values referred to those at 298° K are used (99). Enthalpies and entropies of intermolecular interaction were correlated for solutions, pure liquids, and crystals (6). Quite generally, for any temperature-dependent physical quantity, the activation parameters can be computed in a formal way, and correlations between them have been observed for dielectric absorption (100) and resistance of semiconductors (101-105) or fluidity (40, 106). On the other hand, the isokinetic relationship seems to hold in reactions of widely different kinds, starting from elementary processes in the gas phase (107) and including recombination reactions in the solid phase (108), polymerization reactions (109), and inorganic complex formation (110-112), up to such biochemical reactions as denaturation of proteins (113) and even such biological processes as hemolysis of erythrocytes (114). [Pg.418]

Laboratory, where he worked with John Longo and Allan Jacobson on the synthesis and characterization of mixed metal oxides and their application in heterogeneous catalysis. He joined the chemistry faculty of Northwestern University in 1984 where he is now Professor of Chemistry and an active member of the Center for Catalysis and Surface Science and the Materials Research Science and Engineering Center. Kenneth Poeppelmeier has published over 250 research papers and supervised approximately 40 Ph.D. students in the area of inorganic and solid state chemistry. He is a Fellow of the American Association for the Advancement of Science (AAAS) and the Japan Society for the Promotion of Science (JSPS) and has been a Lecturer for the National Science Council of Taiwan (1991), Natural Science Foundation of China (1999) and Chemistry Week in China (2004), and more recently an Institut Universitaire de France Professor (2003). [Pg.375]

Apart from the work toward practical lithium batteries, two new areas of theoretical electrochemistry research were initiated in this context. The first is the mechanism of passivation of highly active metals (such as lithium) in solutions involving organic solvents and strong inorganic oxidizers (such as thionyl chloride). The creation of lithium power sources has only been possible because of the specific character of lithium passivation. The second area is the thermodynamics, mechanism, and kinetics of electrochemical incorporation (intercalation and deintercalation) of various ions into matrix structures of various solid compounds. In most lithium power sources, such processes occur at the positive electrode, but in some of them they occur at the negative electrode as well. [Pg.359]


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See also in sourсe #XX -- [ Pg.129 ]




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Activity solids

Inorganic solid

Solids activation

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