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The gold-catalyzed tandem cyclization of 1,2-bis(alkynyl)-2-en-1-ones with indoles offers an efficient and straightforward route to indole-fused polycyclic systems. The process is realized through a cascade carbonyl-yne cyclization/Friedel-Crafts/indole-yne cyclization sequence catalyzed by a single-pot catalyst of gold.  相似文献   
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刘祥伟  陈渝芝  吴永 《高等数学研究》2014,(1):86+124-86,124
依据向量空间的同构关系,以矩阵为工具给出生成子空间的基和维数的求法,并借助两个实例说明其应用价值.  相似文献   
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光的衍射法测量杨氏模量   总被引:1,自引:0,他引:1  
拉伸法测量金属丝杨氏模量的关键是如何测准金属丝在拉力作用下的微小伸长量。本文利用光的衍射法可以较精确地测量长度变化这一特点,对钢丝的杨氏模量进行了测量,给出测量杨氏模量的一种新方法。  相似文献   
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JPC – Journal of Planar Chromatography – Modern TLC - A simple, rapid, and sensitive high-performance thin-layer chromatographic method for analysis of octachlorodipropyl ether (OCDPE)...  相似文献   
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Fe@Fe2O3 core-shell nanowires were synthesized via the reduction of Fe3+ ions by sodium borohydride in an aqueous solution with a subsequent heat treatment to form Fe2O3 shell and employed as a cathode catalyst for non aqueous Li-air batteries. The synthesized core-shell nanowires with an average diameter of 50–100 nm manifest superior catalytic activity for oxygen evolution reaction (OER) in Li-O2 batteries with the charge voltage plateau reduced to ~3.8 V. An outstanding performance of cycling stability was also achieved with a cutoff specific capacity of 1000 milliampere hour per gram over 40 cycles at a current density of 100 mA g?1. The excellent electrochemical properties of Fe@Fe2O3 as an O2 electrode are ascribed to the high surface area of the nanowires’ structure and high electron conductivity. This study indicates that the resulting iron-containing nanostructures are promising catalyst in Li-O2 batteries.  相似文献   
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Intestinal flora play an important role in human's immune system. Many bacteria adhere to the wall of the testinal wall. These Intestinal flora help digestion, and also stop their disease-causing counterparts from invading. Most of the current researches focused on the interaction between cells and the construction of organs, but few researches studied on the role of microorganisms and cells. Here, we developed an in vitro living cell systems to simulate the structure, absorption, transport and pathophysiological characteristics of the human intestinal tract and the key microbial symbiosis. The co-culture of Clostridium butyricum(C.butyricum) and colon cancer cells showed a different immune effect. C. butyricum could inhibit the proliferation of HCT116 cells, cause cell cycle arrest and promote apoptosis. But it had no significant effect on Caco-2 cells. Thus, basic functional characteristics of the gut were successfully simulated in a controlled microfluidic system. This approach is suggested as a powerful method in the investigation on drug metabolism and intestinal diseases.  相似文献   
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The essential oil of Sagittaria trifolia, a well-known famous medicinal foodstuff in China, was analyzed for the first time using GC-MS. Twenty-eight constituents were identified. The major components of the oil were hexahydrofarnesyl acetone (62.3%), tetramethylhexadecenone (5.8%), myristaldehyde (4.7%), n-pentadecane (2.9%), and 2-hexyldecanol (2.9%).The antimicrobial activity of the essential oil was evaluated against seven microorganisms, including two clinically isolated strains and five reference strains, using microbiological cylinder plate assay and broth microdilution methods. The results showed that the oil had a significant antimicrobial effect on four of them. This antimicrobial activity can partly explain why the oil is used medicinally during childbirth and for skin diseases in Chinese traditional medicine. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 419–420, September–October, 2006.  相似文献   
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