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991.
HAN Jun DENG Chao FANG Ru LI YiZhi WANG LeYong& PAN Yi Key Laboratory of Mesoscopic Chemistry Ministry of Education School of Chemistry Chemical Engineering Nanjing University Nanjing China State Key Laboratory of Coordination Chemistry 《中国科学:化学》2010,(4)
Three tripod molecules, tris(2-methoxy-5-nitrobenzyl)phosphine oxide (1), tris(2-butoxy-3-methyl-5-nitrobenzyl)phosphine oxide (2), and tris(3-nitrobenzyl)amine (TNBA), were synthesized and crystallized. The structures of 1, 2, and their comparison (TNBA) were determined by X-ray crystallography. It is noteworthy that compound 1 interacted with adjacent molecules via π-π stacking and C-H···π interactions to yield an open supramolecular network with the porosity P in 8.9%, whereas compound 2 gathered closely... 相似文献
992.
LI ZhengDong & FU YanNing Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Graduate University of Chinese Academy of Sciences Beijing 《中国科学 数学(英文版)》2010,(2)
Consider a generalized 3-body problem. The attraction force between any two bodies is proportional to the two masses and the b-th power of the mutual distance. Albouy and Fu have obtained the optimal upper bound of the number of generalized Euler configurations for the cases b 1 and b = 2, 3. This paper obtains the optimal upper bound for the remaining real values of b in a systematic way. 相似文献
993.
ZHANG QingChao PANG ShuJie LI Yi & ZHANG Tao Key Laboratory of Aerospace Materials Performance School of Materials Science Engineering Beijing University of Aeronautics Astronautics Beijing China 《中国科学:物理学 力学 天文学(英文版)》2011,(9)
Bulk metallic glasses (BMGs) with large supercooled liquid region are promising materials for superplastic forming. In this paper, we demonstrate a microstructure-based strategy to pinpoint the composition with the largest supercooled liquid region in La 86 x Al 14 Cu x (x=16 at%-20 at%) metallic glass system. By monitoring the changes in crystallization behavior of the glassy alloys with composition to search for the alloys exhibiting eutectic crystallization, the glassy alloys with the largest supercooled... 相似文献
994.
Mudasir Ahmad Tantry Reehana Khan Seema Akbar Abdul Rouf Dar Abdul Sami Shawl Mohammad Sarwar Alam 《中国化学快报》2011,22(5):575-579
An unusual oleanane triterpene(1) was isolated from aerial parts of Rhododendron campanulatum.The compound had shown prominent antibacterial and immunomodulatory activities.The structure of the compound was determined by spectroscopic data including 1D and 2D NMR spectral analysis. 相似文献
995.
LI Ming DAI ChangJian & XIE Jun Key Laboratory of Display Materials Photoelectric Devices Ministry of Education Tianjin China School of Science Tianjin University of Technology Tianjin 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
The odd-parity high-lying states of the Sm atom are investigated systematically by a three-color resonant excitation scheme with two different excitation paths.The two intermediate states,4f 6 6s7s 7 F 0 and 4f 6 6s7s 7 F 1 are employed for paths I and II,respectively.Fifty-seven bound states are detected with paths I and II in the energy range between 44188 and 45515 cm 1,while 64 autoionizing states are found in the energy range from 45528 to 45761 cm 1.Not only the level energies of all observed states,b... 相似文献
996.
Hong Ping HE Yue Mao SHEN Xiao Sheng YANG Bin Gui WANG Ling LI Xiao Jiang HAO * Laboratory of Phytochemistry Kunming Institute of Botany the Chinese Academy of Sciences Kunming . The Key Laboratory of Chemistry for Natural Prod 《中国化学快报》2001,(1)
Spiraea japonica L. (Rosaceae) is widely distributed in Yunnan Provence, P. R. China. Previous chemical investigations on S. japonica and its varieties have led to the report of 7 new atisane-type diterpenoids and 38 new diterpene alkaloids of atisine- and hetisine-type1-11. This paper describes the isolation and structure elucidation of two new diterpene alkaloids named spiratines A and B (1-2). Their structures were elucidated on the basis of 1D and 2D NMR experiments (HMQC, HMBC, 1… 相似文献
997.
ZHANG Hong YU Yaoting PAN Jilun XU Yuanping ZHU Hesun Bioactive Materials Research Laboratory Nankai University Tianjin The Center of Materials Research Beijing Institute of Technology Beijing 《Chinese Journal of Reactive Polymers》2001,(1)
1. INTRODUCTION Bioreactors using membranes as substrates of cell cultures have become widely used for hybrid liver support systems [1]. For enhancing and prolonging the metabolism of the bioreactors, cytocompatible membranes are necessary because the cell culture is closely affected by the substrate surface. Surface factors considered to be important in cell culture are the concentration of ionic groups, the nature of polar and non-polar groups and the hydrophilic-hydrophobic balance [2].… 相似文献
998.
Min WANG You Gang MAO* Yan Ying LU Ren Fei YANG Fei LI Jia Cong SHEN Key Laboratory for Supramolecular Structure Spectroscopy of Ministry of Education Jilin University Changchun 《中国化学快报》2001,(11)
It has been known that the propagation rate coefficient (kp) will change with monomer conversion, Friss, Hamielec et al.1-5 have proposed many formulas about kp to fit this change. In order to obtain the relation between Arrhenius parameters and monomer conversion, a group of kp values at the same monomer conversion must be measured. We adopted a new method through analysis of kp values measured by usual experimental techniques for this purpose. Firstly, we chose a value of monomer convers… 相似文献
999.
介绍了研究分子反应动力学的两大主要实验方法之一的气室法、在研究有热原子参与的反应所取得的新进展,讲述了此方法“新用”的理论依据及相应的实验条件,至此,可以获得对分子反应动力学更精细的信息,例如,态-态分辨的微分反应截面,并对两大方法进行了“现代”对比。还对两方法的发展前景作了适度的分析。 相似文献
1000.
Xi Rong HUANG * Yue Zhong LI Guo Liang YANG Li Li LIU Yin Bo QU Wen Juan ZHANG State Key Lab of Microbial Technology of China Shandong University Jinan Key Lab for Colloid Inferface Chemistry of the Education Ministry of Chin 《中国化学快报》2001,(5)
Lipase is one of the hydrolases. It catalyzes the hydrolysis of triglycerides, liberating fat acids. Based on its catalysis and the response of a glass electrode to the acids, a glass-electrode-based lipase sensor can be fabricated1, which has great potential in clinical medicine for the detection of blood fat in human serum samples.The immobilization of lipase on the bulb of a glass electrode is the key to the development of the sensor. In addition to its response time, which has a lot to do … 相似文献