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971.
HU Fang ZHANG Chun-hua ZHANG Song MING Xing CHEN Gang WEI Ying-jin WANG Chun-zhong . School of Materials Science Engineering Shenyang University of Technology Shenyang P. R. China . College of Physics State Key Laboratory of Superhard Materials Jilin University Changchun . College of Physical Science Technology Huanggang Normal University Huanggang 《高等学校化学研究》2011,(3):528-530
1 Introduction Low-dimensional nanostructures, such as nanorods, nanowires, and nanotubes, have received much attention for their superior optical, electrical, catalytic and magnetic properties. 相似文献
972.
Chuan Fu College of Architecture North China University of Technology Beijing China 《Acta Mechanica Sinica》2011,27(5):817-822
The sealed,tuned liquid column gas damper (TLCGD) with gas-spring effect extends the frequency range of application and efficiently increases the modal structural damping.Active tuned liquid column gas damper (ATLCGD) is developed for the vibration control of plane asymmetric buildings subjected to earthquake excitation,improving the performance of the passive control scheme.The active behaviour is obtained by adjusting the pressure at the end of the liquid column using a pressurised reservoir.The classical linear quadratic regulator (LQR) design is presented as a straightforward approach to optimal control.Numerical simulations indicate a significant vibration reduction of plane asymmetric buildings by active control within the strong motion of the dynamic response. 相似文献
973.
WANG Cui ZHANG Quan ZHANG XiaoFeng LIU Jing & LIU WeiPing College of Biological Environmental Engineering Zhejiang University of Technology Hangzhou China Key Laboratory of Environmental Remediation Ecosystem Health Ministry of Education College of Environmental Resource Sciences Zhejiang University Hangzhou China 《中国科学:化学》2010,(5)
Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) enantioselectivity.The re... 相似文献
974.
Zhi Jian WU* Si Yuan ZHANG Laboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 《中国化学快报》2000,(12)
HgBa2Can-1CunO2n+2+( (n=1, 2, 3, 4) 1 are tetragonal with space group space P4/mmm. For n=1,2,3, nearly single-phase crystals were obtained, while for n=4, the sample was primarily a mixture of the n=3 and 4 phases. These materials also possessed the highest Tc values yet observed for any superconductors. In this paper, the valences of elements in the title compounds were calculated from bond valence sum method 2. The calculated bond covalency, valences of elements were summarized in Table … 相似文献
975.
利用已合成的聚醋酸乙烯酯-甲基丙烯酸缩水甘油酯-甲基丙烯酸烯丙酯大孔共聚物。醇解后与6-氨基正已酸反应,进一步在EDAC的作用下实现与间氨基苯硼酸的偶联,得到亲水性的亲和吸附剂;配基密度为0.865mmol/g干树脂,偶联效率为89%,以云芝糖肽八方地,吸附容量为53.7mg/g干树脂,为醇解前的7.7倍。 相似文献
976.
This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90. 相似文献
977.
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
978.
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
979.
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
980.
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