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551.
Chun YANG * Key Lab of New Materials Technology of China National Packaging Corporation Zhuzhou Engineering College Zhuzhou College of Chemistry Environmental Science Nanjing Normal University Nanjing 《中国化学快报》2003,14(1):96-99
Recently, a novel method of modification, i.e., functionalizing the internal surface of mesoporous materials has been reported1-5, owing to the large pore size, the silanol groups, which are in a big population in mesoporous materials, can chemically couple with the active groups of some bulky organic functional molecules. Based on this approach, one can obtain novel solid basic catalysts. Here we functionalized the hexagonal and hexagonal-like mesoporous silica materials SBA-3 and HMS wi… 相似文献
552.
IntroductionFunctional polymers bearing chiral moietiesand the extended conjugatedπ system have attract-ed considerable attention during the pastdecade[1,2 ] .The enantiodifferation properties ofsuch macromolecules give rise to multiple applica-tions in the fields of asymmetric catalysis,chiralsensors,polarized light emission and nonlinear op-tical materials[3 ,4] .Especially the incorporation ofoptically active binaphthyls in the main chain ofconjugated polymers can lead to an efficient ands… 相似文献
553.
§1.IntroductionIn[5],MaliavinandNualartdefinedthenotionof(real)smoothmartingalesandwethenprovedin[6]thattheprocesofquasisureq... 相似文献
554.
Jiu Yu LIU Hui Yuan GUO* Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences Peking Union Medical College Beijing 《中国化学快报》2004,15(5)
Quinolone antibacterial agents have emerged as one of the dominant classes chemotherapeutic drugs for the treatment of various bacterial infections1. We have focused our attention on the modification of the C-7 basic group of the quinolone which has been most varied. In 1987, Uno et al.2 reported that 3-hydroxypyrrolidine quinolones showed more active antibacterial activities than Norfloxacin in vivo. In 1998, Fujita et al.3 reported that 2-aminomethylpyrrolidine quinolones have the same … 相似文献
555.
Jin Wen WANG Yi Yuan PENG Cheng Xue ZHAO* Department of Chemistry Shanghai Jiaotong University Shanghai Department of Chemistry Jiangxi Normal University Nanchang 《中国化学快报》2002,13(8)
Because the solvent dependency of aN, g factors and line widths of some bulky and stable di-t-alkyl nitroxides1, ESR has been proved to be a useful tool in searching for the nature of medium effects ( solvation ) to chemical reactivity. A large number of fluorinated nitroxides with a wide variety of structures have been generated and subjected to extensive studies in our laboratory2. Amongst, t-butyl perfluoroalkyl nitroxides, much less hindered, with noβ-H atoms, have been employed as sp… 相似文献
556.
Ke Qiang DING Zhen Bin JIA Qing Fei WANG Juan BAI Ru Ting TONG Xin Kui WANG Hui Bo SHAO* Institute of Coal Chemistry Chinese Academy of Science Taiyuan Department of Chemistry Hebei Teachers University Shijiazhuang D 《中国化学快报》2002,13(4)
Recently, the adsorption behavior of protein on solid substrate has attracted much attention for the reason that adsorption on a substrate is the first key step for other further electrochemical investigation1. Meanwhile the free adsorption could provide a relative well-ordered structure, with which some fundamental study could be carried out conveniently2. As we know, the electrochemical impedance spectroscopy (EIS) method has become one of the powerful techniques to detect the change of i… 相似文献
557.
Jin Long WANG Zi Cheng LI Bin XIONG Lei XIE Liang Jie YUAN Ju Tang SUN* College of Chemistry Molecular Sciences Wuhan University Wuhan 《中国化学快报》2003,14(12):1303-1305
Today, batteries with high capacity, good cyclability, long life and environmental goodness are much required to meet some pressing demands of our modern society. In principle, lithium ion cells can satisfy these requirements1. But the properties of the cathode materials have limited the further development of the lithium ion cells. The studied cathode materials before were mainly LiCoO2, LiMn2O4, LiNiO2. The LiCoO2 has disadvantages including cost and environmental risk although it is… 相似文献
558.
Le Xin SONG* Department of Chemistry University of Science Technology of China Hefei 《中国化学快报》2002,13(10)
The interaction between ethyl orange (Eto, guest) and β-cyclodextrin dimers (1a~d, host) bridged with 2-t-butoxycarbonyl(Boc)-amino diacid was investigated. A remarkable synergic complexation of two cavities in host molecule was observed. 相似文献
559.
The chemistry of samarium (II) iodide (SmI2) is of current interest in organic synthesis. SmI2 has been developed as a powerful, versatile and ether-soluble single-electron reductant and many examples have been reported of its use in the reduction of various functional groups1. Though SmI2 is a useful reagent, storage is difficult because it is very sensitive to air oxidation. On the other hand, metallic samarium is stable in air and has strong reducing power (Sm3+/Sm=-2.41 V). These pr… 相似文献
560.
Tong WU De Yun KONG Hui Ting LI* Shanghai Institute of Pharmaceutical Industry Shanghai 《中国化学快报》2002,13(11)
Helicia nilagirica Beed. belongs to the plant of Proteaceae family. The seeds of the plant is for treatment of insomnia and neurasthenia in Jingpo nationality in Yunnan Province1. Helicid and helicidol were isolated from the seeds of the plant2,3, and the helicid was recorded in the Yunnan Pharmacopoea at the 1987 edition. The chemical constituents of the leaves of this plant has not been reported yet in the literature. This paper is concerning the study of the chemical component of the… 相似文献