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101.
Xue Mei LUO Wei Jiang HE Yu ZHANG Zi Jian GUO Long Gen ZHU* State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 《中国化学快报》2000,11(11)
Selectively chemical cleavage of peptides and proteins is one of the most important reactions in both chemical and biochemical processes. Over the past decade, the interaction of palladium(II) complexes with methionine, cysteine and histidine-containing peptides and proteins and the hydrolytic cleavage of the corresponding amide bond by Pd(II) complexes have been extensively studied1-13. However, reports concerning the directly selective hydrolysis of peptides and proteins with other simple … 相似文献
102.
Zhi NA Bei JIANG Hui YANG Zhong Wen LIN Han Dong SUN* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming Chemistry Deparment of the College of Life Science Chemistry Yunnan University K 《中国化学快报》2001,(8)
Isodon enanderianus (Hand. -Mazz.) H. W. Li, has been used in folk medicine as anti-inflammatory and detoxified agent1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. In order to find more biologically active substances, we have carefully investigated the chemical constituents of I. enanderianus collected in Shiping county of Yunnan province, and as a result, enanderi… 相似文献
103.
Retention Behaviors of Uronic Acid-containing Polysaccharides and Neutral Polysaccharides in HPGPC 总被引:2,自引:0,他引:2
Cui Ping LIU Xing Feng BAO Ji Nian FANG* Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 《中国化学快报》2001,(10)
The determination of molecular weights (Mw) of polysaccharides has served as an important process since the physical properties of the polysaccharides are closely related to their Mw and/or molecular weights distribution (MWD). For Mw and MWD determinations, high performance gel permeation chromatography (HPGPC) has gained wide acceptance as a preferred method due to its high sensitivity, speed and reproducibility. In chromatography, it is well known that the molecular weights are determ… 相似文献
104.
1 INTRODUCTIONItwaswellknown thatelementsofthesecondary and higherrow are in generaldifficulty to form multiplebondsin which apπ hybridized stateisinvolved〔1〕.Thus,simple compounds containing multiple phosphorus carbon bonds,such as methyl dynephosphine( HC≡P) 〔2 - 3〕 and methylenephosphine( H2 C=PH〔4〕,are notstableat room temperature.Three methods to stabilize compounds containing double ormultiple bond involving phosphorusatom in the pπ hybridized state are often used.The f… 相似文献
105.
James空间的推广 总被引:1,自引:0,他引:1
R.H.Lohman和P.G.Casazza[2]就自反的、具有对称的块P——Hilbert基的Banach空间进行了讨论,给出了一阶次自反Banach空间的一种构造方法。本文在一类具有IS型基的Banach空间上进行了推广,并给出了构造一阶次自反空间的更一般性的方法。 以下记号S、的意义同[2],文中IS序列、ESA序列、SA序列及单调基、正规基的定义可见[2]、[3]。并总设E是Banach空间,{x_i}是E之IS型单调正规基。 一般的James空间定义类似[2],区别在于对于a=(a_i)∈S和我们定义: 相似文献
106.
Si WANG Pei Cheng ZHANG Ruo Yun CHEN De Quan YU* Institute of Materia Medica Chinese Academy of Medical Sciences 《中国化学快报》2001,(9)
Goniothalamus cheliensis Hu (Annonaceace) is a small tree or shrub in Yunnan Province, southwest of China. Acetogenins, styryllactones and alkaloids1-3 from the genus were reported in the previous literature and many of them showed strong cytotoxic activities against a number of human cancer cell lines4. The titled plant has been the subject of our investigation due to the impressive cytotoxicity of its organic extract against mouse lymphocytic leukemia cells in preliminary pharmacological s… 相似文献
107.
在240℃水热体系中首次合成出系列纳米晶固溶体(CeO 相似文献
108.
109.
Hong Ping LI Hai Fei ZHANG Jun LIU Bu Xing HAN* Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2001,(4)
There are some unique advantages for chemical reactions in SCFs. For example, reaction rates, yields, and selectivity can be tuned by pressure or small amount of cosolvent. SCFs can be used to replace environmentally undesirable solvents. It is not surprised that in recent years the use of SCFs as solvents for chemical reaction media has received much attention. However, mechanism for the effect of pressure and cosolvents on chemical reactions is not very clear. Tautomeric reactions are id… 相似文献
110.
声誉是企业的一项重要无形资产,能够增进企业对消费者的吸引力。本文从消费者视野探索企业声誉在电子商务消费者信任建立过程的作用机制。将感知的安全性引入技术接受模型,建立了理论模型及假设,并应用结构方程模型分析软件进行了检验。结果表明,企业声誉通过消费者感知的安全性、有用性和易用性正向影响消费者信任,消费者感知的安全性、易用性也通过感知的有用性影响消费者信任。 相似文献