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941.
942.
Dandan Bu Yuying Wang Na Wu Wei Feng Donghui Wei Zhanxian Li Mingming Yu 《中国化学快报》2021,32(5):1799-1802
Based on 4-bromo-1,8-naphthalic anhydride, one novel ratiometric fluorescence H2S-probe (IDNA) was designed and synthesized. Further studies indicate that IDNA can sensitively recognize H2S (detection limit of 7 μmol/L) with good selectivity and anti-interference ability. In addition, IDNA has satisfactory photostability in HeLa cells, ability of mitochondrial co-localization, and can be utilized in fluorescence imaging of H2S. 相似文献
943.
Chemistry of Natural Compounds - Arugosin R (1), a new arugosin type metabolite, was isolated from Talaromyces flavus. Its structure was characterized by detailed analyses of IR, MS, 1D, and 2D NMR... 相似文献
944.
Hui Qiang Tao Chen Zhuo Wang Wenqian Li Yunzhe Guo Jie Yang Xueshun Jia Hui Yang Weibo Hu Ke Wen 《中国化学快报》2021,31(12):3225-3229
The development of heterogeneous catalysts with substrate shape, size or electronic constitution selectivity is a huge challenge in photocatalysis. Reported herein is a host-guest interaction strategy to endow photocatalysts with special selectivity. By adjusting the precursors, conjugated macrocycle polymers (CMPs) with pillar[5]arene struts (CMP-1 and CMP-2) and a corresponding non-pillar[5]arene-contained conjugated organic polymer (COP-1) were prepared and the photocatalytic activities toward sulfide derivatives were investigated. The sulfides showed similar conversions when COP-1 was used as a photocatalyst, but exhibited significant differences when it turned to the CMPs. Remarkably, the conversion yield of S-1 achieved near 18 folds over the one of S-2 when CMP-2 was used as a catalyst. Mechanism studies confirmed that the “host-guest” effect of pillar[5]arene struts in CMPs was the main cause of the difference. The present work establishes CMPs as novel heterogeneous photocatalysts with substrate selectivity, and such a method will inspire the researchers concerning preparation of heterogeneous catalysts with excellent selectivity. 相似文献
945.
946.
Xian Tao Ke‐Cheng Shen Qing‐Yun Tang Meng Feng Jiang‐Tao Fang Yu‐Long Wang Ying‐Zhong Shen 《应用有机金属化学》2012,26(7):323-329
New N‐silver(I) acetylbenzamide complexes of type Ln?AgNC9H8O2 (L = PPh3; n = 1, 2a; n = 2, 2b; n = 3, 2c; L = P(OEt)3; n = 1, 2d; n = 2, 2e; n = 3, 2f) were prepared. These complexes were obtained in high yields and characterized by elemental analysis, 1H NMR, 13C{H} NMR, 31P{H} NMR and IR spectroscopy, respectively. The molecular structure of 2b has been determined by X‐ray single‐crystal analysis in which the silver atom is in a distorted tetrahedral geometry and crystallizes as cis–trans. New N‐silver(I) acetylbenzamide complexes have a four‐membered ring, which could influence their chemical and physical properties and modulate volatility. Metal organic chemical vapor deposition experiments were carried out successfully at 400°C and 450°C using 2e as precursor for the deposition of silver films, respectively. The high‐purity silver film obtained at 400°C is dense and homogeneous. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
947.
Through a two-step vacuum-filtration process, WSe2 and MoS2 nanosheets were sequentially deposited onto a polymeric nanoporous support, forming WSe2/MoS2 bi-layered heterostructure. Highly rectified ion transport phenomenon is observed through the heterogeneous 2D layered membranes. 相似文献
948.
949.
Cangyi Chen Ping Tang Feng Qiu 《Journal of polymer science. Part A, Polymer chemistry》2014,52(24):1583-1599
Binary polymer brushes, including mixed homopolymer brushes and diblock copolymer brushes, are an attractive class of environmentally responsive nanostructured materials. Owing to microphase separation of the two chemically distinct components in the brush, multifaceted nanomaterials with functionalized and patterned surfaces can be obtained. This review summarizes recent progress on the theory and simulations related to binary polymer brushes grafted to flat, spherical, and cylindrical substrates, with a focus on patterned morphologies of multifaceted hairy nanoparticles, an intriguing class of hybrid nanostructured particles (e.g., nanospheres and nanorods). In particular, powerful field theory and particle-based simulations suitable for revealing novel structures on these patterned surfaces, including self-consistent field theory and dissipative particle dynamics simulations, are emphasized. The unsolved yet critical issues in this research field, such as dynamic response of binary polymer brushes to environmental stimuli and the hierarchical self-assembly of binary hairy nanoparticles, are briefly discussed. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1583–1599 相似文献
950.
Bomin Feng Xiuju Wu Ling Li Wei Gao Dr. Weihua Hu Prof. Chang Ming Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(49):11560-11565
It remains challenging to rationally synthesize iron/nitrogen-doped carbon (Fe/N-C) catalysts with rich Fe−Nx atomic active sites for improved oxygen reduction reaction (ORR) electrocatalysis. A highly efficient Fe/N-C catalyst, which has been synthesized through a spatial isolation strategy, is reported. Derived from bioinspired polydopamine (PDA)-based hybrid microsphere precursors, it is a multifunctional carrier that loads atomically dispersed Fe3+/Zn2+ ions through coordination interactions and N-rich melamine through electrostatic attraction and covalent bonding. The Zn2+ ions and melamine in the precursor efficiently isolate Fe3+ atoms upon pyrolysis to form rich Fe−Nx atomic active sites, and generate abundant micropores during high-temperature treatment; as a consequence, the resultant Fe-N/C catalyst contains rich catalytically active Fe−Nx sites and a hierarchical porous structure. The catalyst exhibits improved ORR activity that is superior to and close to that of Pt/C in alkaline and acidic solutions, respectively. 相似文献