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911.
Promoted by metallic cadmium which was produced by reduction of CdCl2 H2O with samarium in situ, allyl bromide and α-bromocarboxylates react with diorgano diselenides in aqueous solutions to give allylic-type selenides and α-selenocarboxylates in moderate to good yields.  相似文献   
912.
The direct electron transfer of glucose oxidase (GOD) immobilized on a composite matrix based on porous carbon nanofibers (PCNFs), room-temperature ionic liquid (RTIL), and chitosan (CHIT) underlying on a glassy carbon electrode was achieved. The combination of the PCNFs, RTIL, and CHIT provided a suitable microenvironment for GOD to transfer electron directly. In deaerated buffer solutions (pH 7.0), the cyclic voltammetry of the GOD/PCNFs/RTIL/CHIT composite films showed a pair of well-defined redox peaks with the formal potential of −0.45 V (vs. SCE). The synergistic effort of the PCNFs, RTIL, and CHIT also promoted the stability of GOD in the composite film and retained its bioactivity.  相似文献   
913.
Fe0.95S1.05 with high reactivity and stability was incorporated into WS2 nanosheets via a one-step solvothermal method for the first time. The resulted hybrid catalyst has much higher catalytic activity than WS2 and Fe0.95S1.05 alone, and the optimal WS2/Fe0.95S1.05 hybrid catalyst was found by adjusting the feed ratio. The addition of Fe0.95S1.05 was proven to be able to enhance the hydrogen evolution reaction (HER) activity of WS2, and vice versa. At the same time, it was found that the catalytic effect of the hybrid catalyst was the best when the feed ratio was W : Fe=2 : 1. In other words, we confirmed that there is a synergistic effect between W- and Fe-based sulfide hybrid catalysts, and validated that the reason for the improved HER performance is the strong interaction between the two in the middle sulfur. WS2/Fe0.95S1.05-2 hybrid catalyst leads to enhanced HER activity, which shows a low overpotential of ∼0.172 V at 10 mA cm−2, low Tafel slope of ∼53.47 mV/decade. This study supplies innovative synthesis of a highly active WS2/Fe0.95S1.05 hybrid catalyst for HER.  相似文献   
914.
915.
916.
Qi-Huang Zheng  Jing Su 《合成通讯》2013,43(20):3467-3476
Solid-liquid phase transfer catalytic elimination reaction for the preparation of acyclic and cyclic ketene acetals has been developed.  相似文献   
917.
Four new coordination polymers, [Cd(3-TPTP)Cl]2 (3-HTPTP = 4′-(3-tetrazolylphenyl)2,2′:6′2′′-terpyridine, 1), {[Cd(3-TPTP)(pBDC)0.5]?4H2O}n (pH2BDC = 1,4-benzenedicarboxylic acid, 2), {[Mn(3-TPTP)(mBDC)0.5]?5H2O}n (mH2BDC = 1,3-benzenedicarboxylic acid, 3), and [Pb(3-TPTP)(H2O)2]?OH (4), were obtained. Compounds 13 are composed of binuclear [M2(3-TPTP)2] ring as building unit. In 1, the binuclear rings pack into a 3-D supramolecular framework via various hydrogen bonds. In 2 and 3, the binuclear rings are connected by mBDC2? and pBDC2?, respectively, resulting in two types of 1-D chains. In 4, the mononuclear [Pb(3-TPTP)] units are connected by Pb?N weak interactions, giving a chiral 1-D coordination chain, which is further connected by O–H?N interaction to form a chiral 3-D supramolecular framework. The phase purity of 14 and luminescence properties of 1, 2, and 4 were also investigated.  相似文献   
918.
919.
In this study, a series of linear poly(triazole)s (PTAs) were successfully synthesized by the metal‐ and solvent‐free, thermal click polymerization of diazide and dialkyne (A2 + B2) monomers. All click polymerizations proceeded smoothly at 80 °C in an open atmosphere without protection from oxygen and moisture. After being polymerized for 36 h, the crude polymer was further fractionated into three fractions using a multistep precipitation method. By selectively choosing precipitating agents, this process produced poly(triazole) fractions with low polydispersity index (<1.30). The resulting PTAs are soluble in common organic solvents and stable at a temperature up to 320 °C. Furthermore, the methyl benzoate moieties in the main chain can serve as useful building blocks for further postpolymerization functionalization, yielding 1,2,4‐triazole derivatives. This functionalization strategy offers potential for the development of novel triazole‐based materials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   
920.
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