For silica-supported

Figure 2. Normalized EXAFS data (copper K absorption edge) at 100°K, with associated Fourier transforms and inverse transforms, for silica supported copper and ruthenium-copper catalysts. Reproduced with permission from Ref. 8. Copyright 1980, American Institute of Physics.

The role played by the support of influencing the surface composition of supported bimetallic clusters has only recently begun to receive some attention. Miura, a ( ) have shown that the nature of the support can play an important role in determining not only the surface composition of the supported bimetallic clusters but also the morphology of the particles. For silica-supported Pt-Ru... 

Table I. Catalyst Composition and Surface Composition for Silica-Supported Rh-Ru Bimetallic Catalysts...

The highest ethylene polymerization activity for a tetradentate salen-type group 4 complex was reported for silica supported (64) (600gmmol-1h bar ).193 Activities for a range of related zirconium and titanium complexes such as (65)-(67) are typically an order of magnitude lower.194-196... 

Figure 10.28 AES for silica-supported Pd nanoparticles before and after 141 torr CO exposure. Inset Difference spectrum between the AES for clean and poisoned Pd particles. (Reprinted from Ozensoy, E. et al., J. Phys. Chem. B, 108, 4351-4357, 2004. Copyright 2004. With permission from American Chemical Society.)...

Figure 5.17 Structure of the ligand, linker precursor and immobilized ligand assembl)r for silica supports and subsequent functionalization with [Rh(COD)2]Bp4. (Redrawn from Pugin and Blaser [49].)...

Molecular Insight for Silica-Supported Organometallic Chemistry through Transition Metal Silsesquioxanes... 

The absence of any significant change in N as the amount of the metal was increased sixfold is considered as a convincing test of the lack of influence of transport phenomena under reaction conditions (18). The activation energy of reaction was constant within experimental error on all catalysts (Table III). The values of N obtained for silica-supported catalysts can be compared with the results published in the literature after extrapolation to our conditions from Aben el al. (4) we get N = 52, and... 

In an alternative approach the substrate is adsorbed first on the solid. Thus when stearic acid is adsorbed in a monolayer on alumina and exposed to chlorine or t-butyl hypochlorite in tetrachloromethane at - 35-20 °C, a selective chlorination is obtained with formation of mainly co, co-1 and co-2 chlorostearic acids75. Similar results are reported for silica-supported stearic acid76. The selectivity observed is significantly improved compared with the results obtained with V-chlorodialkylamines as chlorinating agents77 or with direct chlorination in a homogeneous system78. 

Nucleophilic substitution of the chlorine atom of 1.1 with potassium diphenylphosphide (KP(C6H5)2) gives 3.1 [7, 8]. The reaction of 3.1 with Rh(I) and Pt(II) transition metal complexes (Eq. 1-3) yields compounds which can be used as models for silica supported catalysts [8],... 

Dependence of specific rates of cyclohexene hydrogenation calculated as turnover numbers on the platinum surface area estimated by hydrogen chemisorption for silica-supported Pt samples measured here at 295K (O) and at 3I3K ( ) at two different reaction times and previoubly K... 

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