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41.
Jia Rong Li~* Li Jun Zhang Xi Quan Yang Qing Li Dong Wang Chun Xia Wang Da Xin Shi Qi Zhang School of Chemical Engineering Environment Beijing Institute of Technology Beijing China 《中国化学快报》2008,(1)
Two different skeletons of heterocyclic compounds,quinoline and quinazolinone analogs could be obtained by a novel one-pot synthesis from substituted 3-amino-1 H-benzo[f]chromene-2-carbonitrile derivatives and cyclohexanone in DMF in the catalyst of anhydrous zinc chloride under reflux.A plausible mechanism was proposed. 相似文献
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随着高温超导技术的发展,可用于交变电磁场条件下且临界温度高于77K的高温超导线材已经得到商业化应用,液氮温区的高温超导磁体冷却技术也取得了巨大进步。本文作者设计了一种高温超导磁体液氮零蒸发冷却系统,并进行了相关性能试验。结果表明,整个试验过程中,液氮无损耗,实现液氮零蒸发功能;系统液氮温度处于70K~77K之间,且温度可控,为高温超导磁体在特定温度下的性能研究提供了条件;给出了液氮温度与系统净输出冷量的关系,并与理论计算进行了比较;提出了影响系统性能的关键问题。 相似文献
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Jian Guo DENG Xiao Bin DING Yu Xing PENG* Albert S. C. CHAN* Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu Open Laboratory of Chirotechnology Department of Applied Biology Chemical Technology 《中国化学快报》2001,(11)
Among various conducting polymers, polyaniline (PANI) is a unique and promising candidate for practical applications because it is not only highly stable in air and in some solvents, but also exhibits dramatic changes in its electronic structure and physical properties in protoactivate state1,2,3. The carbon nanotubes (CNTs) have been proven to possess exotic properties, such as high mechanical strength, flexibility and electric conductivity. The study of carbon-based nanostructures and ma… 相似文献
47.
Jing Chao DONG Run Tao LI* Tie Ming CHENG* Department of Bioorganic Chemistry School of Pharmaceutical Sciences Peking University Beijing 《中国化学快报》2001,(12)
Since Daly reported the structure of epibatidine and its potent analgesic activity in 19921, study on the synthesis of epibatidine and its derivatives and relationships between the structure and activity of epibatidine has received much attention2. During the course of our research for the synthesis of epibatidine derivatives, N-boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was used as the key intermediate to construct the skeleton of epibatidine via the 1, 3-dipolar cycloaddition (Scheme 1). Ac… 相似文献
48.
Qing Yan CHENG Wei LI Ying ZHOU Ming Hui ZHANG Nai Jia GUAN Ke Yi TAO* Department of Material Chemistry Nankai University Tianjin 《中国化学快报》2001,(12)
The various distillation of petroleum contains arenes. For environmental protection, the hydrogenation of arenes becomes important. The amorphous alloy is a new class of material with special catalytic properties for reduction arenes1-4. In this paper, we prepared the Ni-B/TiO2 and Ni-B/Al2O3 amorphous catalysts by impregnation and reduction by KBH4 solution. Their catalytic activities for hydrogenation arenes were tested by the hydrogenation of 1,3,5-trimethylbenzene (TMB) in the co… 相似文献
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Qing L? Ming Hua LIU* Laboratory of Colloid Interface Science Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences 《中国化学快报》2001,(12)
Langmuir monolayer at the air/water interface is the basis to understand the molecular arrangement and to fabricate the organized molecular films1. Bolaamphiphiles describes the molecules in which two head functional groups are linked by one or two hydrophobic chains2,3. In comparison with the one-headed amphiphile, abundant configurations of Langmuir monolayer are expected in bolaamphiphiles. Generally, three kinds of configurations of the Langmuir monolayers of bolaamphiphile at the air/w… 相似文献
50.
Jian Liang YE Xing Wang ZHOU Zhong CHEN* Zhi Wei CHEN Pei Qiang HUANG* Department of Chemistry Department of Biology Xiamen University Xiamen 《中国化学快报》2001,(11)
K3[VO(O2)2(C2O4)]2H2O, (abbr. BpV (ox)) pertains to peroxovanadium (abbr. pV) complexes, which have been attracted considerable attention nowadays, since they are inhibitors of tyrosine phosphatase and may be developed into a new kind of drugs for the treatment of diabetes1. According to the evidence on water-biperoxovanadium, the molecular mechanism of insulin-like effects of pV involves in irreversibly oxidizing the catalytic cysteine at the active site of the target enzyme2,3. However… 相似文献