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531.
Synthesis and Characterization of Amphiphilic Block Copolymer Containing PVP and Poly(5-benzyloxytrimethylene carbonate) 总被引:2,自引:0,他引:2
Ying Xia WANG Feng HE Ren Xi ZHUO* Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 《中国化学快报》2006,17(2)
Amphiphilic block copolymers have attracted great interest recently, especially for thebiomedical uses1, . The hydrophilic blocks improve the biocompatibility of copolymer, 2while the hydrophobic blocks enhance the mechanics of the material and providever… 相似文献
532.
ZHOU Jin-xia ZHANG Yong-chun GUO Xin-wen * State Key Laboratory of Fine Chemical Dalian University of Technology Dalian P. R. China 《高等学校化学研究》2005,21(2):217-219
Introduction Separation,recoveryofolefinorremovalof tracequantitiesofolefinfromitsmixturesbyusing π-complexatonisamostpromisingsolution,com- paredwithenergy-intensivedistillationorotheral- ternatives.π-Complexationisasubgroupofchemi- calcomplexationwhereamixtureisbroughtinto contactwithasecondphasecontainingacomplex- ingagent[1].Forexample,theadsorbentscontain- ingAg+orCu+canselectivelyadsorbolefinfroman ethylene/ethaneorpropylene/propanemixture. Becausetheπ-complexationbondsarestronger th… 相似文献
533.
Yu Hua ZHANG Wei Qiang ZHANG Yu Gang CHEN Zhi CHEN Xin Yi ZHU Huan Wang JING Yuan Qi YIN* State Key Laboratory for Oxo Synthesis Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 《中国化学快报》2001,(1)
Due to the framework chirality optically active clusters can provide the proof that a cluster as a whole, and not one of its fragments, acts as a catalyst, most of the work have been directed to the synthesis of tetrahedron-type chiral clusters1-3. However, there remains another major problem to obtain the pure enantiomers. Although Vahrenkamp had obtained some pioneering results in this area before 19901, only several racemic chiral clusters have been separated into pure enantiomers until now… 相似文献
534.
Xin Cheng LIAO Xing Wang WANG Jing Chao TAO* Department of Chemistry Zhengzhou University Zhengzhou 《中国化学快报》2002,13(10)
Crown compounds offer a variety of interesting functions based on their specific bindings of organic guest species1,2. In particular, they can act as carriers in ion- extraction, membrane transport, and phase-transfer reactions. In contrast to the large variety of synthetic ionophores for cation transport, there are only a few examples of synthetic anion transport ionophores. Therefore, it appears highly desirable to search for a new class of ionophores with excellent transport abilities fo… 相似文献
535.
HE Feng-qi WANG Bao-lei LI Zheng-ming* Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin P. R. China 《高等学校化学研究》2006,(6)
IntroductionPlants have a more extensive biosynthetic capacitythan animals, which is attributed to the fact that ani-mals rely on their diet for the supply of many biochemi-cal compounds and their precursors. Owing to thisdifference, plants contain numero… 相似文献
536.
Ying DU Wen Jun CHEN Sheng Ying QIN* Department of Chemistry Sichuan University Chengdu 《中国化学快报》2004,15(10)
The fission product 137Cs accounts for a large fraction of the radioactivity in high-levelnuclear waste (HLW). Because of the hazard to environment and the widespreadapplication of 137Cs gamma radiatior1, a need has arisen to develop improved methods forthe removal and recovery of radiocesium from these wastes. Reports have shown thatsome calixcrown compounds may be highly selective for Cs cation2, but, since thesynthesis of them is difficult and the cost is high, it might obviate their use… 相似文献
537.
Zhi Hui HE Wen Rui JIN* School of Chemistry Chemical Engineering Shandong University Jinan 《中国化学快报》2002,13(9):871-873
Capillary electrophoretic immunoassay (CEIA) is a new analytical technique1,2. In CEIA, the detection methods were UV absorbance detection1 and laser induced fluorescence detection (LIF)2. However, The UV detection is lack of sensitivity. The LIF is difficult to use due to its high cost, and furthermore, most biological fluids are strongly luminescent when excited by the laser in the blue or green region of the spectrum. In our present work, a capillary electrophoretic enzyme immuno… 相似文献
538.
Su Qin HAN Er Bao LIU Hua LI* Institute of Analytical Science Northwest University Xi’an School of Chemistry Material Science Shanxi Normal University Linfen College of Chemistry Life Science Tianjin Normal University Tianjin 《中国化学快报》2005,(8)
Tetracycline antibiotics (TCs) are active against a wide range of gram-positive and gram-negative bacteria, being extensively used in human and veterinary medicine to treat and prevent bacterial infections1. Among the TCs, TC, OTC and CTC are commercially available and permitted for human administration. However, the degradation products occurring in storage conditions might induce potential adverse effects. Thus, many studies have focused on the development of a rapid, sensitive and reli… 相似文献
539.
Qixiang Wang* Guoqing Ning Fei Wei Guohua Luo Department of Chemical Engineering Tsinghua University Beijing P. R. China *Author to whom correspondence should be addressed. 《中国颗粒学报》2003,(6)
1. Introduction Carbon nanotubes (CNTs), a kind of the most advanced nanomaterials with novel properties and promising for many applications, have aroused great interest of the world in a number of research fields (Iijima, 1991; Baughman et al., 2002; Iijima & Ichihashi, 1993; Rao & Govindaraj, 2002; Rueckes et al., 2000; Adrian et al., 2001; Javey et al., 2003). Catalytic chemical vapor deposition (CCVD) is re-garded as the most suitable method for the preparation of microstructured CN… 相似文献
540.
IntroductionThispaperisconcernedwiththenumericalsolution ,byfinitedifferencemethod ,ofthefollowingsingularlyperturbednonlocalboundaryvalueproblem :Lu≡-εu″ +a(x)u=f(x) ( 0 <x<l) ,( 1 )L0 u≡-εu′( 0 ) +γu( 0 ) =μ0 , ( 2 )L1u≡u(l) -δu(d) =μl ( 0 <d<l) ,( 3 )whereεisasmallpositiveparameter,… 相似文献