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991.
Wei Li YANG Jun TIAN Qiang ZHANG Shu Lin PENG Li Sheng DING* Chengdu Institute of Biology Chinese Academy of Sciences Chengdu School of Pharmacy West China University of Medical Sciences Chengdu 《中国化学快报》2001,(2)
There are only three species in the genus Diuranthera (Liliaceae), which is endemic in the southwest of China1. Four steroidal saponins, diuranthosides A-C and chloromalo-side A were isolated from the fresh roots of D. major. This paper deals with the structure elucidation of two new steroidal saponins, diuranthosides D and E, which were isolated from the methanolic extract of whole plant of D. inarticulata Wang et K. Y. Lang.Diuranthoside D (1), [(]-38 (c 0.08, pyridine), afforded galac… 相似文献
992.
Zhang Jing CHANG Wu Xiang YANG Cao Wei LIANG* Faculty of Science Beijing University of Chemical Technology Beijing 《中国化学快报》2001,(9)
Recently, the application of supercritical fluid technology is very interested, and it is applied in many areas for its special properties. The performance of supercritical fluid (SCF) as a solvent can be greatly affected by addition of an entrainer to the system. An entrainer can be added to a supercritical fluid to enhance its solvent strength and/or selectivity. Critical point data for these dilute supercritical fluid-cosolvent systems are imperative for the design of efficient separation … 相似文献
993.
Yan Ling ZHANG Wei Sheng LIU Yang LI Xue Yi MA* Yao Zu CHEN National Laboratory of Applied Organic Chemistry Department of Chemistry Lanzhou University Lanzhou Department of Chemistry Zhejiang University Hangzhou 《中国化学快报》2001,(4)
The importance of Vitamin A for human health has been stressed in resent studies1, meanwhile its derivative so-called retinoic acid (RA) has been widely used as pharmaceutical to treat several types of skin disease and cancer2,3. However the application of retinoic acid is restrained for its poor water solubility, unstability and side effect on the human body.Cyclodextrins (CDs) are macrocyclic oligosaccharides built up from 6, 7, or 8 glucopyranose units called (, (, and (-CD, respectively… 相似文献
994.
Hong Ping HE Yun ZOU Yue Mao SHEN Xiao Yan HAO Guo Yin ZUO Xiao Jiang HAO * Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming . Department of Medicinal Chemistry Guiyang Medical College 《中国化学快报》2001,(7)
Micromelum integerrimum (Rutaceae) is a shrub growing in Yunnan Province. Leaves and barks of this plant have been used for the treatment of dysentery, and arthritis1. Previous researches revealed that this plant contained coumarins2-8. Micromelin, the main chemical constituent of this plant, showed significant inhibition against leukaemia P-388 cell line (T/C 149% at 10 mg/kg) but was inactive in lower doses, and also showed significant activity (T/C 228% at 1.25 mg/kg) against Lewis lung… 相似文献
995.
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
996.
The TiO2 gel doped with UO22 and Eu3 has been prepared by a sol-gel method. The quenching of the UO22 emission by Eu3 and the energy transfer from the excited state of UO22 to the ground state of Eu3 have been investigated. The energy transfer has been studied by the measurement of luminescence lifetime τ, calculations of energy transfer efficiency ηET and energy transfer rate WET. The experimental results indicated that the quenching is combined static and dynamic mechanism, but the static mechanism is dominant. 相似文献
997.
Jun LING Yi Feng ZHANG* Zhi Quan SHEN Institute of Polymer Science Zhejiang University Hangzhou 《中国化学快报》2001,(1)
Aliphatic polycarbonate is a series of useful biodegradable materials attracting more interests recently. Poly(2,2-dimethyltrimethylene carbonate) (polyDTC) has been studied for a long time. Polymerization of DTC can be catalyzed by alkyl metals1, trifluoromethanesulfonic acid and its esters2, alcohol/methylaluminum diphenolate system3 and etc. Herein tris(2,6-di-tert-butyl-4-methylphenoxo) lanthanides (Ln(OAr)3, Ln=La, Nd) are firstly applied to initiate the polymerization of DTC. Ln(O… 相似文献
998.
CHEN YuJin SHI XiaoLing CAO MaoSheng & ZHU ChunLing School of Materials Science Engineering Beijing Institute of Technology Beijing China Micro-Nano Technologies Research Center Hunan University Changsha College of Science Harbin Engineering University Harbin College of Material Science Chemical Engineering 《中国科学G辑(英文版)》2009,(7)
CdS/α-Fe2O3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2O3 nanorods, were synthesized via a three-step process. The diameters and lengths of CdS nanorods can be tuned by changing the ethylenediamine (EDA) and Cd ion concentrations. The magnetic investigations by superconducting quantum interference device indicate that the hierarchical nanostructures have an Morin transition at lower temperature (230 K) than that of the single bulk α-Fe2O3 materials (263 ... 相似文献
999.
1000.
Xing LU Yue WANG Hai Yuan ZHANG Chun Ji NIU* Jia Zuan NI Key Laboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 《中国化学快报》2001,(9)
With the wide application of rare earth fertilizer and medicines1, more and more rare earths enter into environment, and also into human body via food chain. Now it is very urgent to study the biological effect of rare earths on human health and environment. After entering into human body by whatever route, lanthanide ions are transported to secondary deposition sites mainly via the plasma in the blood stream. So it is very important to study lanthanides speciation in human blood plasma. Becau… 相似文献