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One-step in situ polymerization induced precipitation method had varied topography, the complex structure of mesoporous silicon dioxide microspheres it with Noyori ligand Ru Cl (p-cymene) [(R, R) -Ts-DPEN] complex supported ruthenium catalysts prepared and applied to asymmetric transfer hydrogenation of acetophenone. Field emission scanning electron microscopy and nitrogen adsorption-desorption isotherm means proved microsphere type mesoporous silica microspheres and supported ruthenium catalyst, combined with transmission electron microscopy showed that the ruthenium elements evenly distributed on the silica spheres; by infrared spectra showed the presence of the catalyst and the reaction between hydrogen bonding substrates; based on this study the factors affecting the pore structure of the carrier, the reaction conditions on the catalytic properties. 

The results show that ruthenium ligand loaded onto a small aperture, the high surface area silica microspheres in favor of asymmetric hydrogen transfer reaction of acetophenone, which leads to pore confinement effect mesoporous silica microspheres of optical activity and selectivity of catalytic asymmetric reactions significant role in promoting. At 40 ℃, 0.2 ml acetophenone reaction conditions 16 h, supported ruthenium catalysts for the asymmetric transfer hydrogenation of acetophenone conversion rate and enantioselectivity can reach 64.1% and 93.4%, respectively.

Ethylene - vinyl alcohol copolymer (EVOH) film-forming polymer, in glycerol and polyethylene glycol (PEG-600) is a mixed diluent nanoscale silica additive, thermally induced phase separation ( TIPS) prepared EVOH porous film using a scanning electron microscope (SEM) observation of a cross section of the microporous membrane and the surface morphology, and carried out its permeability, hydrophilicity, porosity and pore size distribution and mechanical properties analysis and discussion the results show that: EVOH film surface with an average pore size of the silica content in the deposition system decreases with an increase after the first increase in cross-section of the honeycomb cells membrane structure; membrane water flux, porosity and hydrophilic with silicon dioxide content decreases with an increase after the first increase; when the silica content of 0.5%, the water flux of 511 L / (m2 · h), a porosity of 74.0%, the contact angle is 44.8 °


 

 

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