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981.
Ling Hua CAO * Hong Yun GAO Chuan Jian ZHOU Yu Ting LIU College of Chemistry Chemical Engineering Xinjiang University Urumqi State Key Laboratory of Elements-Organic Chemistry Nankai University Tianjin 《中国化学快报》2004,(2)
Sugar derivatives whose molecules contain trivalent phosphorus groups have been coming into use for different scientific purposes, including the synthesis of metal com- plexes. These metal complexes of glycosyl phosphites are effective chiral catalysts in enantioselective synthesis1-5such as hydrogenation, cyclopropylation, hydro phosphina- tion and hydrosilylation of achiral olefin. Furthermore, this kind of compounds are also widely applied in biology and medicine area and open up a new fie… 相似文献
982.
XiaoQuanLU LiNaHU XiaoQiangWANG JingCHEN 《中国化学快报》2004,15(12):1461-1464
Electron transfer (ET) from ascorbic acid (AA) in aqueous to ferrocene (Fc) in 1,2-dichloroethane (DCE) was probed by the scanning electrochemical microscopy (SECM). Therate constants were extracted from the dependence of the steady-state current at ultramicro- electrode (UME, tip) on the distance between the tip and the phase boundary by comparison to theoretical working cures. 相似文献
983.
FuLinYAN AiXiaWANG ZhongJianJIA 《中国化学快报》2004,15(4):423-424
Two new benzofuran derivatives were isolated from the roots ofLigularia stenocephala.Their structures were established by spectroscopic methods and 2D NMR experiments. 相似文献
984.
HaoQinZHANG JinDunLIU 《中国化学快报》2004,15(5):609-610
The preparation of composite charge-mosaic membrane included spinning of hollow fiber as the supporting membrane, preparing a selective layer on the inside surface of the fiber by interracial polymerization. The charge-mosaic membranes show a high salt permeability while retaining sucrose. The charge-mosaic membrane can be effectively used to separate multivalent salts with organic matter of molecular weight great than 300g/mol in industry. 相似文献
985.
YanQiLIU JiuGaoYU XiuPingSUN 《中国化学快报》2004,15(7):853-855
The B-typed starch spherocrystals were prepared by the dissolution and freezing crystallization of acid-hydrolyzed starch obtained by the mild hydrolysis of maize starch. The spherocrystals were characterized with scanning electron microscope (SEM), X-ray diffraction, thermogravimetry (TG) and gel pervasion chromatogram (GPC). The results show that the preparation was a B-type spherocrystal with the average degree of polymerization of 14 glucose units, and the average diameter of crystal particles was about 7μm. 相似文献
986.
一类Pickands型估计量的收敛性 总被引:4,自引:0,他引:4
本文在极值分布指数为负时,给出了一类新的Pickands型估计量,并研究此估计量的相合性、强收敛速度与浙近分布。 相似文献
987.
GAO Cuili JI Quan KONG Qingshan XIA Yanzhi** Advanced fibers Modern Textile Cultivation Base for State Key Laboratory College of Chemical Engineering Qingdao University Qingdao China 《Chinese Journal of Reactive Polymers》2006,(1)
1. INTRODUCTIONThe amount of industrial and municipal waste has been increasing all over the world. Therefore, the design and development of materials capable of being degraded into safe components under specific environmental conditions have become incre… 相似文献
988.
SHI Linmei XIONG Chunhua ** MO Jianjun College of professional Technology Lishui Normality Speciality Lishui Zhejiang China College of Food Science Biotechnology & Environmental Engineering Hangzhou University of Commerce Hangzhou China Department of Chemistry Lishui Teachers College Lishui Zhejiang China 《Chinese Journal of Reactive Polymers》2003,(1)
1.INTRODUCTIONThesynthesis,characterizationandsorptionpropertyofpolymericmaterialshavebeenstudiedbytheauthorsandotherresearchersinrecentyears[1~9].Diglycolamidicacidresin(DAAR)isanovelpolymericmaterialwhichcontainsafunctionalgroup[-N(CH2COOH)2].Itnotonlypossessesprotonthatcanexchangewithcation,butalsooxygenatomsthatcancoordinatedirectlywithmetalions.SoDAARcanbewidelyusedinthesorptionofmetalions.Inthisarticle,thesorptionpropertiesofDAARforSm(III)wereinvestigated.Somebasicsorption… 相似文献
989.
本文运用非线性变换、摄动方法结合上、下解方法得到了一类含梯度项的二阶半线性椭圆型方程爆炸解的存在性. 相似文献
990.
YU Miao LIU Shu-xia~ ZHANG Chun-dan GAO Bo SUN Chun-yan XIE Lin-hua WANG Chun-ling CHENG Hai-yan Key Laboratory of Polyoxometalates Science of Ministry of Education College of Chemistry Northeast Normal University Changchun P. R. China 《高等学校化学研究》2006,(4)
IntroductionRational designs and syntheses of inorganic-organ-ic hybrid materials constructed from flexible ligandshave received considerable attention because of theirnovel structures as well as their special functional prop-erties[1,2]. Multicarboxylate… 相似文献