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排序方式: 共有673条查询结果,搜索用时 468 毫秒
581.
582.
Jin Long WANG Zi Cheng LI Bin XIONG Lei XIE Liang Jie YUAN Ju Tang SUN* College of Chemistry Molecular Sciences Wuhan University Wuhan 《中国化学快报》2003,14(12):1303-1305
Today, batteries with high capacity, good cyclability, long life and environmental goodness are much required to meet some pressing demands of our modern society. In principle, lithium ion cells can satisfy these requirements1. But the properties of the cathode materials have limited the further development of the lithium ion cells. The studied cathode materials before were mainly LiCoO2, LiMn2O4, LiNiO2. The LiCoO2 has disadvantages including cost and environmental risk although it is… 相似文献
583.
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
584.
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
585.
Synthesis and Crystal Structure of N′-(4-fluorobenzylidene)-2-(1H-1,2,4-triazole-1-yl)acetohydrazide
LI Wei-hua ZHANG Shu-fang + HOU Bao-rong YU Zhi-gang *. Institute of Oceanology Chinese Academy of Sciences Qingdao P. R. China. College of Chemistry Chemical Engineering Ocean University of China Qingdao P. R. China 《高等学校化学研究》2006,(5)
IntroductionBoth triazole derivatives and Schiff base have beenreported to possess significant antifungal[1—3]and plantgrowth regulatory activities[4—6].Triazole drugs are alsovery common in the medical field,which has given animmense impetus to the res… 相似文献
586.
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
587.
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
588.
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
589.
Xiwei LIU~* Tianping CHEN~ 《数学年刊B辑(英文版)》2007,28(6):737-746
In this paper,the authors investigate the synchronization of an array of linearly coupled identical dynamical systems with a delayed coupling.Here the coupling matrix can be asymmetric and reducible.Some criteria ensuring delay-independent and delay- dependent global synchronization are derived respectively.It is shown that if the coupling delay is less than a positive threshold,then the coupled network will be synchronized.On the other hand,with the increase of coupling delay,the synchronization stability of the network will be restrained,even eventually de-synchronized. 相似文献
590.
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