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991.
IntroductionTransitionmetal-carbonylsystemsM-COhavebeenthefocusofcontinuousstudiesboththeoreticalyandexperimentaly[1,2].Theim... 相似文献
992.
WANG Qilin ZHANG Yinghui QU Aiqin WANG Hairen XU Zhenguo College of Life Science Shandong University Jinan Rongcheng Hongyangshen Group Shandong Province 《Chinese Journal of Reactive Polymers》2001,(2)
1. INTRODUCTION Blood fat primarily contains cholesterol, cholesterol ester, phosphatide, triglyceride and free fatty acid in serum of human being and mammalian. Under physiological conditions, the lipids transport in the form of lipoproteins linked with the proteins. Except for the free fatty acid linked with albumin, the other lipids are linked with the globular proteins into high-density lipoproteins (HDL), low density lipoproteins (LDL), very low density lipoproteins (VLDL) and so… 相似文献
993.
LI Zhong WANG Hongjuan XI Hongxia XU Kefeng WEN Jun Research Institute of Chemical Engineering South China University of Technology Guangzhou 《Chinese Journal of Reactive Polymers》2001,(2)
1. INTRODUCTION In some cities of China, cancer and breath system diseases caused by the pollution of volatile organic compounds (VOCs) have been obviously increasing. The VOCs includes BTEX (benzene, toluene, ethylbenzene, and xylene), aldehydes, cresol, phenol, acetic acid, polynuclear aromatic hydrocarbons (PAHs), which have long-term human health implications. Emission of the VOCs has threatened the health of people seriously [1,2]. The pollution of the VOCs mostly hails from… 相似文献
994.
Characteristics of single- and multi-finger mesa InGaAs/InP double heterojunction bipolar transistors (DHBTs) are compared. The current gain decreases with the increasing number nf of the emitter fingers due to the mutual thermal interaction between the fingers. The Kirk current can be as high as 150mA for four-finger DHBT. No degradation of the peak of the current gain cutoff frequency ft is found for multi-finger DHBTs. The peak of the maximum oscillation frequency fmax decreases with an increase of nf due to the increasing parasitic resistance of the base. The results are very helpful for applications of the common-base DHBTs in power amplifiers operating at very high frequencies. 相似文献
995.
ThesystemsconsistingofafluorophorelinkedtoacrownethermoietyareeXtensivelyinvestigated'-'.Sincedrasticchangesintheirphotophysicalpropertiescanbeobservedbycomplexationwithion,theycanbeusedforionicdetection"'.Recentreportsfocusonazamacrocyclicderivativeswithfluorophores"',inwhichthefluorophoreandcrownethermoietywerelinkedvianitrogenatom.Thepresenceofabasicnitrogenatomwhichiseasytobeprotonatedleadstoelthancementoffluorescencequantumyield""'.Wereplacedthenitrogenatomofthecrownbyoxygenwhichisexpect… 相似文献
996.
1INTRODUCTIONInrecentyears,ourresearchgrouphasstudiedsystematicalycycloadditionreac tionsoftheC=Ndoublebondsinthebenzoheteroa... 相似文献
997.
FGS was isolated and purified from laminaria japonica by enzymolysis,chromatography methods and so on.The high blood fat model was established by feeding mouse on high fat feedstuff.Compared with control group,the concentration of HDL-C.the ratio of HDL-C.TC increased.while the concentration of TC,LDL-C and TG decreased in experimental groups,Conclusion:FGS was an effective serum lipid regulator and can be developed as medicine and health food. 相似文献
998.
Microbial epoxide hydrolases from bacterial and fungal sources?1? are hi ghly versatile catalysts for the asymmetric hydrolysis of chiral epoxides which are extensively employed as useful building blocks for the synthesis of various biologically active products in the pharmaceutical and agrochemical industries. Microorganism means allows an unlimited supply of these enzymes for preparative -scale applications. Phenyl glycidyl ether (PGE), an aryl epoxide, is a potenti ally useful compound in the synthesis of chiral amino alcohols and bioactive com pounds such as ?blockers. No suitable biocatalyst with sufficiently high enan tioselectivity (E?20) for the kinetic resolution of this compound was previ ously found among bacteria and fungi. This prompted us to screen epoxide hydrola se-producing microorganisms with higher enantioselectivity toward phenyl glycid yl ether from soil samples. 相似文献
999.
Schiff碱N,N’-双水杨醛缩-1,6-己二胺的光致变色光谱研究 总被引:1,自引:0,他引:1
用稳态和时间相关荧光光谱、紫外 -可见吸收光谱和傅立叶变换红外光谱等方法研究了 Schiff碱N ,N -双水杨醛缩 -1 ,6-己二胺 ( BSH)的光致变色行为 .确定了光致变色的产物为双质子转移的酮式结构 . 相似文献
1000.
THE STUDY OF INTERACTION OF SOLID-LIQUID ADSORPTION SYSTEM BY USING THE FLOW INJECTION-SPECTROPHOTOMETRY SYSTEM 总被引:2,自引:0,他引:2
HE Guangping CHEN Bingren XU Huiling LIU Guihua Department of Chemistry South China Normal University Guangzhou 《Chinese Journal of Reactive Polymers》2001,(2)
1. INTRODUCTION Flow injection analysis is a method that a determinate volume of sample is injected to an airless and continuous flow carrier consisted of suitable liquids, and then is put into a detector to be record absorbency, electrode potential and other physical parameters. This automatic analytical method is characterized by fixed time, quantified sampling, less sampling and good system stability [1]. The new automatic analysis for liquid has been developed quickly since Ruzi… 相似文献