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551.
Polypropylene( PP) has developed into one of the most useful plastic materials.Ithas many attractive properties,among them,a relatively low price.It also possesses awide range of possibilities for chemical modification[1 ,2 ] .The structure and morphologyof PP have a directimpacton the final properties. Therefore,there is growing interestinunderstanding the structure and morphology of stereoregular PP[1~ 6] . For isotactic PP(i PP) ,extensive structural and morphological studies have be… 相似文献
552.
Yun Gen LIU Shao Bai LI* National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2001,(12)
Natural diarylheptanoids have significant bioactivities. Some of them are potent inhibitors against prostaglandin biosynthesizing enzyme (PG synthetase) and 5-lipoxygenase (LT synthetase)1-2. Compound 1 was firstly isolated from Alnus rubra bark3. So far its synthesis has not been reported yet. Herein, we report the synthesis of compound 1. Meantime, compound 24 was also obtianed as an intermediate. Compound 7 and 16 were converted to compound 10 and 18 respectively, because compound 1… 相似文献
553.
A Convenient Synthesis of Diacyl Selenides by Selenium Transfer Reaction of Primary Selenoamides 总被引:1,自引:0,他引:1
Hua Rong ZHAO* Xin Jian ZHAO Xian HUANG* Department of Chemistry Zhejiang University Hangzhou Zhejiang Institute of Calibaration Testing for Technical Superision Hangzhou 《中国化学快报》2001,(10)
Aryl selenoamides are rather interesting compounds because they are versatile intermediates in organic chemistry1. It was reported that selenobenzamides have been used as selenium transfer reagents in the synthesis of alkyl diselenides from reactive halides2. We began to investigate the reactivity of arylselenoamides toward acyl chlorides and guess that this reaction would produce acyl diselenides. In surprise we could not find the diacyl diselenides (Scheme 1). Instead diacyl selenides a… 相似文献
554.
Bin SUN Jun Ru CHEN Jia Yuan HU Xian Jun LI* Department of Chemistry Sichuan University Chengdu 《中国化学快报》2001,(11)
As mimetic oxygen carrier or oxidation catalyst, Schiff base cobalt complexes such as Co (II) salen have been widely studied1-4. However their high-price greatly limited their application. The synthesis of cheap furaldehyde Schiff bases and their complexes with Co (II), as well as the dioxygen affinity and biomimetic catalytic oxidation performance of these complexes are worth trying to study. In this paper, the saturated dioxygen uptake of cobalt complexes with different bis-(furaldehyd… 相似文献
555.
Zhong LI Yu Jie WANG Guo Quan LIU Yi CHEN* Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2001,(3)
Detection and peak identification are key factors in developing CE (capillary electrophoresis) methodology. They have become hotspots for many reasons. The most obvious one lies in the revealing of unknown species in the application of CE to biological samples. CE-MS and CE-NMR have since been developed. CE-Raman spectroscopy was also reported1. As compared to the former two methods, the Raman spectroscopy method is highly attractive because it has the potential to provide high-informat… 相似文献
556.
Chun Yang WANG Tong ZHAO* Center for Molecular Science Institute of Chemistry the Chinese Academy of Science Beijing 《中国化学快报》2001,(10)
Thermally resistant structural materials play a key role in the progress of the electronics and aerospace industries. Polybenzoxazine, a novel ring-opening phenolic resin, with superior properties such as no volatile emission when curing, near zero shrinkage and high mechanical performance, can be deemed as alternatives of traditional phenolics. Layered clays dispersed in a polymer matrix on nanoscale reinforced the thermal resistance and mechanical performance of the composite. The prepara… 相似文献
557.
Yu Han GUO Tian Sheng SU* Center for Molecule Science Institute of Chemistry The Chinese Academy of Sciences Beijing 《中国化学快报》2001,(1)
The cross-linked polymer beads with reactive groups as active supports have been widely used in many fields such as chromatographic separation, solid phase synthesis, catalytic reaction, ion exchange and adsorption etc. In resent years, the synthesis and application of monodisperse polymer beads with different structures have been rapidly developed1~4. It is obvious that this type of monosized resin as matrix of active supports will be even more advantageous in some applications. This paper pr… 相似文献
558.
Many drugs or physiologically important compounds are chiral molecules and the optical isomers of them may differ in their pharmacological activities. In some instances differences in undesirable side-effects of these enantiomers are important. So the separation of chiral compounds is becoming increasingly important. Liquid chromatography (LC) is well known as an excellent method for separating and analyzing mixtures of stereoisomers. For resolving the ionic chiral compounds it is available t… 相似文献
559.
Xian LUO Jian De LU Xiao Yun FU* Analytical Testing Center Zhejiang University Hangzhou 《中国化学快报》2001,(7)
Glutathione (GSH) protects human and animal's cells by the exchange with reversible oxidized glutathione (GSSG) when cells meet with oxidants, such as hydrogen peroxide (H2O2) and lipid peroxide. But when GSH meets with hypochlorous acid (HOCl), via the myeloperoxidase-catalysed oxidation of chloride by H2O2, the amount of GSSG formed does not account for all the GSH lost, which is quite different from that we has investigated in the reaction of GSH with H2O21. Prutz proposed the fo… 相似文献
560.
Yong FENG Hai Ming ZHANG Lei LIU Yong Hui WANG Zhao Xiong LIANG Qing Xiang GUO* Department of Chemistry University of Science Technology of China Hefei 《中国化学快报》2001,(7)
It is well known that a substituted cyclodextrin (CD) can often form a self-included complex, in which the substituent group is incarcerated into the CD cavity1. The phenomenon is interesting, as the self-inclusion is a nice model of protein folding2 and it has also been successfully used in the construction of various molecular devices3. Studies have showed that van der Waals force, hydrophobic effect, and electrostatic interaction are the major driving forces leading to the self-inclusion4… 相似文献