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981.
982.
The region of positive electrostatic potentials (σ-hole) has been found along the extension of the C–I bond in the iodine-ylide CH2IH, which suggests that the iodine-ylide could interact with nucleophiles to form weak, directional noncovalent interactions. MP2 calculations confirmed that the I···N σ-hole interaction exists in the CH2IH···NCX (X = H, F, Cl, Br, I) bimolecular complexes. The NCCl···CH2IH···NCX (X = H, F, Cl, Br, I) termolecular complexes were constructed to investigate the weakly bonded σ-hole interactions to be strengthened by Cl···C halogen bond. And then, the NCY···CH2IH···NCCl (Y = H, F, Cl, Br, I) termolecular complexes were designed to investigate the enhancing effects of the I···N σ-hole interaction on the Y···C halogen/hydrogen-bonded interactions. Accompany with the mutual enhancing processes of the σ-hole interactions and halogen/hydrogen-bonded interactions in the iodine-ylide containing termolecular complexes, both the I···N σ-hole interactions and Y···C halogen/hydrogen-bonded interactions become more polarizable. 相似文献
983.
Zhujia Feng Tingting Zeng Jun Xuan Yunhang Liu Liangqiu Lu Wen-Jing Xiao 《中国科学:化学(英文版)》2016,59(2):171-174
A dual catalytic system, combing visible light photoredox catalysis and iodide catalysis, has been developed for the functionalization of inert C–H bonds. By doing so, radical allylation reactions of N-aryl-tetrahydroisoquinolines(THIQs) were realized under extremely mild conditions, affording a wide variety of allyl-substituted THIQs in up to 78% yields. 相似文献
984.
R. Jiang H.-Y. Zhu J.-B. Li F.-Q. Fu J. Yao X.-X. Liang R.-Q. Guo G.-M. Zeng 《Journal of the Iranian Chemical Society》2016,13(6):1167-1174
Silver orthophosphate-graphene nanosheets composite (Ag3PO4-GNs) has been fabricated using a facile hydrothermal method. The Ag3PO4-GNs were characterized using XRD, UV–vis DRS and SEM. The photocatalytic activity of Ag3PO4-GNs was evaluated by photocatalytic decolorization of dye aqueous solutions under simulated solar light irradiation. It was observed that Ag3PO4 nanoparticles in Ag3PO4-GNs were attached on the surface of graphene nanosheets.The introduction of graphene nanosheets enhanced remarkably the visible light absorption region of Ag3PO4-GNs compared with bare Ag3PO4. The photocatalytic activity of Ag3PO4-GNs is nearly twice as high as that of the pure Ag3PO4. The removal efficiency can reach more than 90 % by Ag3PO4-GNs under simulated solar light irradiation within 25 min, which might mainly be attributed to high adsorption capacity, extended light absorption range and efficient charge separation. After irradiation for 60 min, 84.70 % TOC mineralization was achieved by Ag3PO4-GNs. Based on the results of detection of active species, the direct oxidization of dye pollutants in aqueous solution by holes takes a major role in the whole decolorization process by Ag3PO4-GNs. As a result, Ag3PO4-GNs with the high photocatalytic activity are proven to be an excellent light photocatalyst for potentially scalable removal of dyes in aqueous solutions and other environmental remediation under simulated solar light irradiation. 相似文献
985.
986.
987.
988.
Xiaojun Zeng Jiarui Xu Renzhong Fu Quan Wang Liang Wang 《Journal of Dispersion Science and Technology》2016,37(6):846-852
A new family of tricephalic tetrasiloxane surfactants containing carbohydrate and hydrocarbon chain (SiC(n + 1)N-GA, in which n + 1 represents a hydrocarbon chain length of 1, 8, 12, 16), was synthesized using two-step method. Their structures were confirmed by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy (1H NMR). Their surface activities and aggregation properties in aqueous solution were investigated by surface tension measurements, transmission electron microscopy, and dynamic light scattering. The results indicated that the critical micelle concentration (CMC) of these surfactants increased and the surface tension (γCMC) at the CMC decreased with an increase in the number of hydrocarbon chain, and they can self-assemble into spherical micelles with average diameters in the range from 5 to 200 nm, which are smaller than for single-headed surfactants. 相似文献
989.
Synthesis,Structures, and Photocatalytic Properties of Zinc(II) and Cobalt(II) Supramolecular Complexes Constructed with Flexible Bis(thiabendazole) and Dicarboxylate Linkers 下载免费PDF全文
Three coordination complexes, namely, [Zn(btbp)(3‐npa)]n ( 1 ), [Co(btbh)(3‐npa)]n ( 2 ), and {[Co(btbb)(5‐nipa)(H2O)] · H2O}n ( 3 ) (btbp = 1,3‐bis(thiabendazole)propane, btbh = 1,6‐bis(thiabendazole)hexane, btbb = 1,4‐bis(thiabendazole)butane, 3‐H2npa = 3‐nitrophthalic acid and 5‐H2nipa = 5‐nitroisophthalic acid) were synthesized under hydrothermal conditions and characterized by physicochemical and spectroscopic methods as well as by single‐crystal X‐ray diffraction. Complex 1 features a fascinating meso‐helical chain, which is further extended into a 2D supramolecular framework involving π ··· π stacking interactions. Complexes 2 and 3 show dinuclear structures. Complex 2 is further connected through C–H ··· O hydrogen bonding interactions to afford a 2D supramolecular layer, whereas complex 3 is further extended to a rare 2‐nodal (3,4)‐connected supramolecular sheet with a point symbol of {3.42.5.6.7}2{3.82} by O–H ··· O hydrogen bonding interactions. The electrochemical behaviors of the two cobalt complexes 2 and 3 were reported. Moreover, the luminescent properties for 1 and the photocatalytic properties for the complexes were investigated. 相似文献
990.
Lin-Wei Zeng Chang-Xin Zhou Jia-Dong Liu Chang-Hong Liu Jian-Xia Mo A-Fang Hou 《Natural product research》2016,30(23):2662-2668
Sixteen new ester derivatives with various partition coefficient (ClogP) values of tanshinone IIA (TSIIA), a major lipophilic component of Salvia miltiorrhiza, were designed and synthesised, including six aliphatic esters (3a–e, 5a), one phosphate ester (4c) and nine aromatic esters (5b–j). Their antimicrobial activities against three Gram-positive bacteria strains, Staphylococcus aureus, Bacillus subtilis, and Bacillus amyloliquefaciens, and two Gram-negative bacteria strains, Pseudomonas aeruginosa and Escherichia coli, as well as two fungi species, Candida albicans and Saccharomyces cerevisiae, were evaluated in vitro by broth microdilution susceptibility tests. The results showed that keeping ClogP values in a certain range is necessary for their antimicrobial activities. For those compounds with ClogP values between 5 and 10, their MIC values showed positive correlations with ClogP values. In particular, compound 3e exhibited fourfold and twofold higher potency than the standard drug amphotericin B against fungi C. albicans and S. cerevisiae with MIC values of 1.95 and 7.81 μg/mL, respectively. 相似文献