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791.
Le Xin SONG* Department of Chemistry University of Science Technology of China Hefei 《中国化学快报》2002,13(10)
The interaction between ethyl orange (Eto, guest) and β-cyclodextrin dimers (1a~d, host) bridged with 2-t-butoxycarbonyl(Boc)-amino diacid was investigated. A remarkable synergic complexation of two cavities in host molecule was observed. 相似文献
792.
XU Wei-Xing* 《物理化学学报》2007,(2)
Nano-materials have been extensively studied in the past[1]. The quantum effect makes the properties of nano-materials dif- ferent from that of bulk materials. A few of publications regard- ing the catalysis, electronic structure, and optics of the nanome… 相似文献
793.
Lian De ZHU Ying Xiu LI Guo Yi ZHU* State key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 《中国化学快报》2002,13(11)
Histidine is one of the necessary basic amino acids in biological bases, which often controls the catalytic activity of enzymes and acts in holding the higher structure of proteins. Furthermore, it is also an important ingredient in pharmaceutical preparations used for treatment of hetpatosis and nephropathy. Therefore, the determination of histidine in biological fluids and pharmaceutical preparations is of great importance. Various methods have been proposed for the detection of histidine … 相似文献
794.
Yong Hui WANG Man Zhou ZHU Tao LIU Qing Xiang GUO* Department of Chemistry University of Science Technology of China Hefei 《中国化学快报》2003,(2)
Photoinduced electron-transfer (PET) reactions are fundamentally important in biology and technology1,2. Because of the complexity of PET in biological systems, many simple compounds were synthesized to look into its detailed mechanism3. In previous papers, we reported the electron transfer reaction in the supramolecular systems assembled by mono-6-p-nitrobenzoyl-b-cyclodextrin 6 and naphthalene derivatives in aqueous solution4. In the present paper the intermolecular electron transfer from … 相似文献
795.
Wei WANG Guang Ming XIA Gui Bao XU Zhi Qiang LIU Qi FANG* State Key Laboratory of Crystal Materials Shandong University Jinan School of Chemistry Chemical Engineering Jinan University Jinan 《中国化学快报》2005,16(1):85-88
Organic molecules that can simultaneously absorb two or more photons in reaching theirexcited states have recently been the subject in various photon-electronic fields. Tomeet the criteria for various nonlinear optical applications, such as three-dimensionaloptical storage1 and up-converted lasing2, molecules with large two-photon absorption(TPA) cross-section σ are required and have been synthesized. These dyes generallybelong to the structural modes of D-π-D, A-π-A3 or D-π-A, where D… 相似文献
796.
The Existence and Long-Time Behavior of Weak Solution to Bipolar Quantum Drift-Diffusion Model 总被引:1,自引:0,他引:1 下载免费PDF全文
Xiuqing CHEN~* Li CHEN~ 《数学年刊B辑(英文版)》2007,28(6):651-664
The authors study the existence and long-time behavior of weak solutions to the bipolar transient quantum drift-diffusion model,a fourth order parabolic system.Using semi-discretization in time and entropy estimate,the authors get the global existence of nonnegative weak solutions to the one-dimensional model with nonnegative initial and homogenous Neumann(or periodic)boundary conditions.Furthermore,by a logarithmic Sobolev inequality,it is proved that the periodic weak solution exponentially approaches its mean value as time increases to infinity. 相似文献
797.
Yan Jing SU Xiong Hui WEI* Department of Applied Chemistry College of Chemistry Molecular Engineering Peking University Beijing 《中国化学快报》2006,17(5):691-694
Several benzo[c]phenanthridine alkaloids (BPA) were found in plants of Caprifoliaceae, Fumariaceae, Meliaceae, Papaveraceae, and Ruracea families1. BPA represent a group of natural products, exhibiting multiple pharmacological properties and biological ac… 相似文献
798.
Chao Zhan WANG Jiang Feng LIU Xin Du GENG* Institute of Modern Separation Science Key Laboratory of Separation Science in Shanxi Province Northwest University Xi''''an 《中国化学快报》2005,16(3):389-392
Human granulocyte colony-stimulating factor (hG-CSF), a single chain polypeptidecontaining 174 amino acid residues (MW=18,800, pI=6.1), is one of the hemopoieticgrowth factors which plays an important role in stimulating proliferation, differentiation,and functional activation of bloodcells1. It contains a free cysteine at position 17 andtwo intramolecular disulfide bonds, Cys36-Cys42 and Cys64-Cys74, and the two disulfidebonds in G-CSF molecule are both required for its bioactivity2. Wh… 相似文献
799.
Ying Hong WANG Kai Sheng HUANG Mao LIN* Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 《中国化学快报》2000,11(12)
Continuous investigation on oligostilbenes from the lianas of Gnetum hainanense resulted in the isolation of a new rhapontigenin dimer, Gnetuhainin P (1), in addition to the dimers of resveratrol and oxyresveratrol reported previously1. Gnetuhainin P (1) was obtained as a yellowish amorphous powder, [(]25D +6.6 (c 0.092, MeOH). The high resolution FABMS m/z 533.1866 [M+H]+ gave a molecular formula of C30H28O9 (C30H29O9 requires 533.1812), which corresponds to a isorhapontigenin dimer. … 相似文献
800.
Peng DIAO Min GUO Ru Ting TONG* Department of Chemistry Hebei Teacher''''s University Shijiazhuang Department of Traditional Chinese Pharmacy Traditional Chinese Medicine College Hebei Medical University Shijiazhuang 《中国化学快报》2000,11(12)
Interest in the properties of organized monolayers has grown enormously in recent years because these monolayers can provide a means to control the interface at a molecular level1. The self-assemblies of alkanethiols and their derivatives were probably the most intensively studied due to their stability, well-packed structure, ease in preparation, and flexibility in designing the tail group2. The adsorption kinetics of thiol monolayer has been studied by using several techniques, including con… 相似文献