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951.
正Chemical reactions catalyzed by solid catalysts have recently expanded rapidly from traditional heterogeneous catalytic reactions to photocatalytic reactions and further to plasmonic-catalytic reactions,however,the fundamental understanding of the commonalities and differences among heterogeneous catalysis, 相似文献
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Effects of shell composition,dosage and alkali type on the morphology of polymer hollow microspheres
Polymer hollow microspheres were prepared by performing alkali treatment on the multilayer core/shell polymer latex particles containing carboxyl groups. Effects of the shell composition and dosage as well as alkali type on the morphology of the microspheres were investigated. Results showed that in comparison with acrylonitrile(AN) and methacrylic acid(MAA), using butyl acrylate(BA) as the shell co-monomer decreased the glass transition temperature(T_g) of shell effectively and was beneficial to the formation of uniform and big hollow structure. Along with the increase of the shell dosage, the alkali-treated microspheres sequentially presented porous and hollow morphology, and the size of microspheres increased, while the hollow diameter increased first and then decreased, and the maximum hollow ratio reached 39.5%. Furthermore, the multilayer core/shell microspheres had better tolerance to NH_3·H_2O than to NaOH. When the molar ratio of alkali to methacrylic acid(MR_(alkali/acid)) for Na OH ranged from 1.15 to 1.30 or MRalkali/acid for NH_3·H_2O ranged from 1.30 to 2.00, the regular polymer hollow microspheres could be obtained. 相似文献
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Influence of Intermolecular Interactions on Valence Tautomeric Behaviors in Two Polymorphic Dinuclear Cobalt Complexes 下载免费PDF全文
Guo‐Ling Li Dr. Shinji Kanegawa Dr. Zi‐Shuo Yao Dr. Sheng‐Qun Su Shu‐Qi Wu Dr. You‐Gui Huang Dr. Soonchul Kang Prof. Dr. Osamu Sato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(48):17130-17135
Two polymorphic structures have been well determined in a valence tautomeric (VT) dinuclear cobalt complex. These polymorphs showed distinct thermal‐ and photomagnetic behavior, and are thus ideal for studying the “pure” intermolecular factors to VT transitions. In polymorph 1A , the VT cations are arranged head‐to‐waist with their neighbors and exhibit weak π???π interactions, resulting in a gradual and incomplete thermal VT transition. In contrast, the cations in polymorph 1B are arranged head‐to‐tail and exhibit relatively strong π???π interactions, leading to an abrupt and complete thermal VT transition with adjustable hysteresis loop at around room temperature. The VT process for both polymorphs can be induced by light, but the light‐excited state of 1B? 2H2O has a higher thermal relaxation temperature than that of 1A? 3H2O. 相似文献
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To simplify the assessment method of soy protein isolate(SPI) functionalities,the viscosity and functionalities of commercial SPI products were studied.Viscosity value(y) increases with increasing concentration(x) and exhibits a highly significant correlation with the exponential equation y = a·ebx.The b values of products are gradually enhanced from dispersion,emulsion and injected to gel type.Products with low b values(<0.2),and high dispersivity were dispersion-type.Products having high b values (>0.4) and gel springiness were gel-type.The other products with centered b value(0.2-0.4),high solubility and emulsifying capacity were emulsion-type. 相似文献
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Jin Liu Xianxue Wang Han Guo Xiaokang Shi Xiaoyu Ren Guosheng Huang 《Tetrahedron》2012,68(5):1560-1565
A novel NH4OAc/CuBr(PPh3)3-induced intermolecular Pummerer-type reaction between free (NH)-indoles and dimethylsulfoxide is first reported, which offers the 3-methylthiomethyl substituted indoles conveniently and efficiently. 相似文献