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951.
952.
1 INTRODUCTIONThestudyofmetal ligandsystemisalwaysthetopicofmetallurgyresearchers .Osseo Asare[1] triedtocompileageneralprogramtoplot φ pHdiagramforMetal NH3 H2 Osystem ,however ,theplotteddi agramdeviatesfrom practicalsolutionduetoitsas sumptions ,whichleadstot… 相似文献
953.
K. Rajarajan Ginson P. Joseph S. Ravi Kumar I. Vetha Potheher A. Joseph Arul Pragasam K. Ambujam P. Sagayaraj 《Materials and Manufacturing Processes》2007,22(3):370-374
Tetrathiourea cadmium(II) tetrathiocyanato Zinc(II) (TCTZ) single crystals were grown in acetone-water mixture solvent using slow solvent evaporation technique and their optical property was studied for the first time. Both thiourea and thiocyanate ligands were combined with the transition metal ions Cd2+ and Zn2+. The nonlinear optical (NLO) efficiency of TCTZ crystal was tested and measured using Kurtz and Perry technique. The dielectric behavior of the sample was also studied. 相似文献
954.
Design of Silica-Supported Dendritic Chiral Catalysts for the Improvement of Enantioselective Addition of Diethylzinc to Benzaldehyde 总被引:1,自引:0,他引:1
This article describes an efficient method to design a heterogeneous catalyst for the enantioselective addition of diethylzinc to benzaldehyde. Combining the immobilization of a dendrimer on a silica surface with the introduction of a long alkyl spacer at the periphery of the dendrimer is found to be effective in improving the conversion, selectivity and enantioselectivity. 相似文献
955.
956.
Surface DEAE groups facilitate protein transport on polymer chains in DEAE‐modified‐and‐DEAE‐dextran‐grafted resins
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Linling Yu Lingli Gong Shu Bai Yan Sun 《American Institute of Chemical Engineers》2016,62(10):3812-3819
Sepharose FF was modified with diethylaminoethyl‐dextran (DEAE‐dextran, DexD) and/or DEAE (D) to fabricate three types of ion exchangers FF‐DexD (grafting‐ligand resin), FF‐D (surface‐ligand resin), and FF‐D‐DexD (mixed‐ligand resin), for protein adsorption equilibria and kinetics study. It was found that both adsorption capacity and uptake rate (effective diffusivity, De) were significantly enhanced by grafting DEAE‐dextran. Notably, the De values on FF‐DexD and FF‐D‐DexD (De/D0 > 1.4) were six times greater than those on FF‐D (De/D0 < 0.3). More importantly, the increase of surface‐ligand density greatly enhanced uptake kinetics on FF‐D‐DexD. The results indicate that the surface ligands assisted the transport of bound proteins on polymer chains in the mixed‐ligand resins. That is, surface ligands worked as “transfer stations” between two neighboring chains, resulting in enhanced transport of bound proteins on chains. The research thus disclosed the unique role of surface ligands in facilitating protein uptake kinetics onto polymer‐grafted ion‐exchangers. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3812–3819, 2016 相似文献
957.
958.
Inside Cover: Improving the Solubility of Artificial Ligands of Streptavidin to Enable More Practical Reversible Switching of Protein Localization in Cells (ChemBioChem 4/2017)
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959.
Inside Back Cover: A Nonbactericidal Zinc‐Complexing Ligand as a Biofilm Inhibitor: Structure‐Guided Contrasting Effects on Staphylococcus aureus Biofilm (ChemBioChem 15/2017)
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960.
Stphanie Lambert Kim Yên Tran Guilhem Arrachart Francis Noville Catherine Henrist Catherine Bied Joël J.E. Moreau Michel Wong Chi Man Benoît Heinrichs 《Microporous and mesoporous materials》2008,115(3):609-617
With the aim of obtaining highly dispersed, immobilized and accessible catalytically active palladium nanoparticles in a silica support with a tailored morphology, a sol–gel cogelation method is developed. Pd/SiO2 catalysts are synthesized in ethanol by concomitant hydrolysis and condensation, i.e. cogelation, of a Pd2+[L–X–Si(OR)3]n complex with Si(OC2H5)4 (TEOS) as network-forming reagent followed by calcinations in air and by reductions of the resulting xerogel catalysts in hydrogen. By varying the nature of L, X and R in the Pd2+ complex, the purpose of the present work is to determine the influence of the nature of the L–X–Si(OR)3 ligand on textural properties of silica and on palladium dispersion in Pd/SiO2 catalysts.By changing the molecular weight of L–X– and thus its bulkiness of L and X, it is observed that with bulkier silylated ligand, the textural properties of resulting gels are strongly modified from micro- and macroporous materials to very highly micro- and mesoporous materials. In the latter ones, the size of silica particles is smaller and their void fraction is very high. In such a case, palladium particles are not trapped inside silica particles and are then able to migrate and to sinter. The Pd/SiO2 xerogel catalysts were evaluated in the hydrodechlorination of 1,2-dichloroethane. 相似文献