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181.
CHAOZi-Sheng* ZHOU Xiao- PingWAN Hui-Lin TSAI Khi-RuiDepartment of Clie-mudry Xiamen University Xiamen Fujian 《天然气化学杂志》1995,(2)
The oxidative coupling of methane(OCM)over ThO_2/CaF_2 catalystwas investigated.The catalyst was found to be active and selective for OCMreaction.At 1153 K,the C_2~ yield was 19.9% with 61.7% C_2~ selectivityand 32.1% CH_4 conversion.XRD results indicated that F~-(?)O~(2-)exchangehappened between ThO_2 and CaF_2 phases.XPS and Raman results suggestedthat the active oxygen species were generated and suitable for OCM reactionover the catalyst. 相似文献
182.
Chuan Jin Hou Xiao Mei Liang Jing Ping Wu Dao Quan Wang~* Key Lab of Pesticide Chemistry Application Technology Department of Applied Chemistry China Agricultural University Beijing China 《中国化学快报》2008,19(4):403-405
Two representative macrocyclic lactones with methoxysulfonyl side chain(5a and 5b)were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloaikylsulfonates(1)in total yields of 45 and 57%,respectively. 相似文献
183.
为了在理论上揭示高斯白噪声激励的薛罗格双匣化学反应模型对弱周期扰动的线性与非线性响应 ,分四态近似和两态近似两种情形 ,基于绝热近似与速率方程方法 ,解析导出线性的和非线性的敏感性以及信噪比的表达式 ,并与数值模拟结果进行比较 ,在一次谐波的意义上得到了解析结果与数值模拟结果的定量一致性 .理论上讲 ,该模型只能表现出奇次谐波的随机共振 ,但数值模拟结果也出现了二次谐波的随机共振 ,其原因可能归结为在数值模拟中有限频率的截断引入了误差 ,也可能归结为信号的高次谐波与背景噪声难以区分所致 . 相似文献
184.
Xue Yan SHI Hong Chao GUO Zhen QIAO Shi Cong HOU Min WANG* Key Laboratory of Pesticide Chemistry Application Technology College of Applied Chemistry China Agricultural University Beijing 《中国化学快报》2002,(10)
For high bioactivity of chiral pesticides, more and more chiral isomers are prepared by enantiomer resolution or asymmetric synthesis, and the sales of chiral pesticides continuously increase in recent years1. 1S-Allethrone I and 1S-propargyllone II are indispensable intermediates for synthesizing 1S-bioallethrin and prallethrin respectively, which are representatives of chiral pesticides. Usually, 1S enantiomers of allethrone and propargyllone are more active than their 1R enantiomers wh… 相似文献
185.
Ping Yan BIE Cheng Lu ZHANG Xuan Jia PENG Xin Fu PAN* Department of Chemistry National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2002,13(9)
Celaphanol A was a diterpene isolated from the stems of Celastrus stephanotifolius1, which have been the subject of continued and growing interest, due to the range of biological activities shown by many members of this family2. Some have been used in traditional medicine3 or as a stimulant4 from ancient times. In order to further study the relationship between the structure and biological activity of the diterpene compound and as an extension of diterpenoid synthesis in our laboratory5, 6, … 相似文献
186.
Li Jun HUANG Yan PANG Ji Mei MIN Li He ZHANG* National Research Laboratory of Natural Biomimetic Drugs Peking University Beijing 《中国化学快报》2001,(7)
Cyclic ADP-ribose (cADPR) 1 (Figure 1), a intracellular Ca2+-mobilizing messenger, is of great interest because of its significant importance in the signal transduction1. However, the biological as well as chemical instability of cADPR limits the studies of its physiological role, at least in some aspect2. Recently, Shuto et.al.3 constructed a mimic of cADPR, cyclic IDP-carbocyclic-ribose 2, in which the 4'-oxo in furanose is substituted by a methylene group and the stability of 2 is i… 相似文献
187.
Cai Hong XU Zhi Jie ZHANG Yong Min LI Zhi Min ZHENG Ze Min XIE* Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences Beijing 《中国化学快报》2001,(1)
Recently, the silicon-nitrogen compounds have received more consideration for their attractive application prospects. Both low molecular weight silazane and polysilazane with high molecular weight are widely used in many aspects. For example, in the processing industry of silicone rubber, silizanes not only can be used as "structure-control additives"1, but also can be used to improve the rubber's heat-resistance and mechanical properties; silicon-nitride ceramics can be prepared by pyrolysis … 相似文献
188.
ZHONG Gui yun LIU Hua XIE Qing lan * Institute of Elemento organic Chemistry Nankai University Tianjin P. R. China 《高等学校化学研究》2002,18(3):277-279
IntroductionThe drug- molecules are called as silyl- drug ifasilicon atom replaced one carbon atom of theorganic- drugs.Generally,they have low toxicityand pro- long efficiency.Many methods have beendesigned in order to decrease the toxicity oforganotin compounds and organosilicon which hasbeen proved to be effective.Torque[1] is a newacaricide made by America Shell Company,itsmolecular formula is [( Ph Me2 Si CH2 ) 3 Sn]2 O.Tacker[2 ] synthesized the compounds( Ph Me2 Si CH2 ) 3 Sn X[… 相似文献
189.
WANG Bai Jing WEI Min ZHANG Li Ping * School of Life Science Northeast Normal University Changchun P.R. China 《高等学校化学研究》2003,19(1):37-40
IntroductionBoth Cordycepsmilitarvs( L.) Link and Cordy-ceps sinensis Sacc belong to the claviceps purpureafamily cordyceps genus,and Cordyceps sinensisSacc has received much attention because of its spe-cial function.But the scarcity of it in quantity andthe difficulty of it to be cultivated have made theapplication of this kind oforganism limited.Cordy-ceps militarvs( L .) Link is relatively easier to becultivated. What is more,the determination ofpharmaceutical chemistry and pharmacolog… 相似文献
190.
Wei Jiang HE Fang LIU Zhi Feng YE Zi Jian GUO Jun Bai LI Long Gen ZHU* State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Laboratory of Colloid Interface Science Center for Molecular Science Institute of 《中国化学快报》2000,11(11)
Since calixarenes and their derivatives have unique coordination abilities to metal ions and inclusion abilities toward neutral organic molecules, they have been widely studied in the field of molecular recognition, transportation and separation1. In order to explore these functions, membranes such as monolayers and Langmuir-Blodgett (LB) films formed by calixarenes, are often used for these purposes2-6. However, a crucial factor that hinders their application is the weak mechanical strength … 相似文献