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排序方式: 共有1005条查询结果,搜索用时 15 毫秒
101.
Kosuke Higashida Haruki Nagae Kazushi Mashima 《Advanced Synthesis \u0026amp; Catalysis》2016,358(24):3949-3954
Dinuclear triply chloro‐bridged iridium(III) complexes bearing chiral diphosphine ligands catalyze the asymmetric hydrogenation of tosylamido‐substituted pyrazines to give the corresponding chiral tetrahydropyrazines with an amidine skeleton in high yield and with high enantioselectivity. Addition of N,N‐dimethylanilinium bromide enhanced the catalytic activity of the iridium complexes and also increased the enantioselectivity of the products by trapping the hydrogenated amine products with HBr from N,N‐dimethylanilinium bromide. The amidine skeleton of the products could be transformed to give chiral piperazinones and piperazines without loss of enantioselectivity.
102.
染料敏化纳米晶太阳能电池的研究进展 总被引:2,自引:0,他引:2
染料敏化太阳能电池是近些年发展起来的新型、高效、低成本的光电池。而起到负载敏化剂以及收集、传输电子作用的光阳极是关系到该电池性能的重要组成部分,且敏化的效果是整个光电池光电转换效率的关键。从染料敏化纳米晶太阳能电池(DSSD s)的结构和工作原理出发,详细阐述了光阳极敏化、敏化剂选择及分类和敏化方法,并对光阳极及其敏化的可能发展趋势做了简要叙述。 相似文献
103.
Mingxin Chang Wei Li Guohua Hou Xumu Zhang 《Advanced Synthesis \u0026amp; Catalysis》2010,352(18):3121-3125
A catalytic complex made from [Ir(COD)Cl]2 [di‐μ‐chloro‐bis(1,5‐cyclooctadiene)diiridium(I)] precursor and (S,S)‐f‐Binaphane ((R,R)‐1,1′‐bis{(R)‐4,5‐dihydro‐3H‐dinaphtho[1,2‐c:2′,1′‐e]phosphepino}ferrocene) ligand effectively catalyzed the enantioselective hydrogenation of cyclic imines with high reactivity and good enantioselectivity. 相似文献
104.
Tsuyoshi Tagata Mayumi Nishida Atsushi Nishida 《Advanced Synthesis \u0026amp; Catalysis》2010,352(10):1662-1666
A new continuous‐flow system for C H borylation has been developed. An insoluble catalyst prepared from chloro(1,5‐cyclooctadien)iridium(I) dimer and 2,2′‐bipyridine‐4,4′‐dicarboxylic acid in the presence of bis(pinacolato)diboron exhibited high reactivity under continuous‐flow processing without the loss of expensive iridium metal. 相似文献
105.
《International Journal of Hydrogen Energy》2023,48(59):22342-22365
A physicochemical model of a water electrolyzer with a polymer electrolyte membrane (PEM) was developed, taking into account the electrochemical dissolution of an anodic iridium catalyst. The dependencies of the rates of iridium loss and electrolysis voltage increase upon the current density were calculated in order to analyze the effect of the iridium dissolution on degradation of the electrolysis cell (EC) performance. As an estimated characteristic of the techno-economic costs of the electrolysis process, the amount of iridium loss from the anode catalyst layer (as a result of electrochemical dissolution) in the course of the generation of 1 kg of hydrogen was calculated. Data were analyzed and a number of regularities of the iridium dissolution and its influence on the rate of degradation of the EC performance were found. In particular, the most efficient ECs in terms of electrolysis voltage (energy consumption for gas production) are, simultaneously, the most unstable (prone to performance degradation) in relation to the iridium dissolution process. An aim of current requirements for water electrolyzers includes reducing the specific consumption of iridium required for hydrogen generation. 相似文献
106.
11% Efficient Ternary Organic Solar Cells with High Composition Tolerance via Integrated Near‐IR Sensitization and Interface Engineering 下载免费PDF全文
107.
G. R. R. A. Kumara A. Konno G. K. R. Senadeera P. V. V. Jayaweera D. B. R. A. De Silva K. Tennakone 《Solar Energy Materials & Solar Cells》2001,69(2)
A method is devised for the deposition of CuSCN on ruthenium bipyridyl dye coated nanocrystalline TiO2 films from a solution in n-propyl sulphide. The dye-sensitized solid state photovoltaic cell formed was found to yield higher short-circuit photocurrent, open-circuit voltage and efficiency compared to the cells made with CuSCN by other deposition techniques. Factors affecting the stability of the cell are investigated. 相似文献
108.
《International Journal of Hydrogen Energy》2022,47(22):11500-11510
Herein, a novel ZnTe-based photocatalyst is successfully synthesized via a facile combination of water-bath and hydrothermal processes. Morphology characterization and X-ray diffraction analysis reveal that ZnTe presents irregular granular shape and cubic crystal structure. Moreover, Mott-Schottky measurement shows that the conduction band potential of ZnTe is ?0.84 V (vs NHE). With Eosin Y (EY) sensitization, ZnTe exhibits superior photocatalytic hydrogen evolution activity (223.5 μmol g?1 h?1). Meanwhile, WC-ZnTe heterojunction is constructed by depositing ZnTe nanoparticles on bulk WC and obtains the optimal H2 generation rate (559.1 μmol g?1 h?1) under EY sensitization. Electrochemical and photoluminescence results further prove that WC as electron bridge could reduce the interfacial resistance and suppress e?-h+ pairs recombination. This study explores the potential application of ZnTe as a newly active photocatalyst in photocatalytic water splitting, and emphasizes the synergistic effect of dye sensitization and bridge engineering. 相似文献
109.
《International Journal of Hydrogen Energy》2022,47(1):228-241
The construction of semiconductor heterojunction for photocatalytic H2 production from water splitting is an efficient and environment-friendly technology. In this work, ZnO/BiOCl (ZBC) and Sn-doped ZnO/BiOCl (ZBC-S) photocatalysts with Z-scheme heterojunction were successfully prepared by simple hydrothermal method. The photocatalytic H2 evolution from water splitting by the as-prepared photocatalysts was investigated. The formation of ZnO/BiOCl heterojunction reduces the recombination probability of the photogenerated carriers. The impurity levels originated from Sn doping reduce the band gap width of ZnO and BiOCl to some extent, thereby enhancing the light absorption ability. The ZBC-S composite exhibits the best photocatalytic activity. In addition, the photocatalytic efficiency of H2 production was improved by sensitization with Eosin Y (EY) dye. The H2 production rate under simulated sunlight reaches 4146.77 μmol g?1 h?1, which is 27 times higher than that of pure ZnO. Finally, the Z-scheme electron transfer route in ZnO/BiOCl heterojunction was determined, and the photocatalytic H2 production mechanism of EY sensitized ZBC-S was proposed. 相似文献
110.
Kate Dunning Adeline Martz Francisco Andrs Peralta Federico Cevoli Eric Bou-Grabot Vincent Compan Fanny Gautherat Patrick Wolf Thierry Chataigneau Thomas Grutter 《International journal of molecular sciences》2021,22(12)
P2X7 receptors (P2X7) are cationic channels involved in many diseases. Following their activation by extracellular ATP, distinct signaling pathways are triggered, which lead to various physiological responses such as the secretion of pro-inflammatory cytokines or the modulation of cell death. P2X7 also exhibit unique behaviors, such as “macropore” formation, which corresponds to enhanced large molecule cell membrane permeability and current facilitation, which is caused by prolonged activation. These two phenomena have often been confounded but, thus far, no clear mechanisms have been resolved. Here, by combining different approaches including whole-cell and single-channel recordings, pharmacological and biochemical assays, CRISPR/Cas9 technology and cell imaging, we provide evidence that current facilitation and macropore formation involve functional complexes comprised of P2X7 and TMEM16, a family of Ca2+-activated ion channel/scramblases. We found that current facilitation results in an increase of functional complex-embedded P2X7 open probability, a result that is recapitulated by plasma membrane cholesterol depletion. We further show that macropore formation entails two distinct large molecule permeation components, one of which requires functional complexes featuring TMEM16F subtype, the other likely being direct permeation through the P2X7 pore itself. Such functional complexes can be considered to represent a regulatory hub that may orchestrate distinct P2X7 functionalities. 相似文献