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991.
The self-assembly of meso-tetra (N-methyl-4-pyridyl) porphyrine tetratosylat (H2TMPyP) on an iodide modified Cu(1 1 1) surface has been studied by means of in situ electrochemical-scanning tunneling microscopy (EC-STM). The I/Cu(1 1 1) surface was found to be a good substrate for the self-assembly of highly ordered layers of porphyrin cations. Furthermore, a reversible structural phase transition within the highly ordered porphyrin layer was observed during variation of the electrode potential, as a consequence of changing electronic properties of the substrate. 相似文献
992.
Zhi‐Gang Li Jing‐Wei Xu Heng‐Qing Jia Ning‐Hai Hu 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):m205-m207
The structure of the title compound, [Cu2Cl2(C12H10N2)]n, contains infinite CuCl staircase‐like chains, which lie about inversion centres. The trans‐1,2‐di‐4‐pyridylethylene molecules also lie about inversion centres and connect the CuCl chains through Cu—N coordination bonds into a two‐dimensional organic–inorganic hybrid network. The planar sheets are stacked along the c axis and associated through weak C—H⋯Cl interactions. The results show a reliable structural motif with controllable separation of the CuCl chains by variation of the length of the ligand. 相似文献
993.
Enhanced Photocatalytic Efficiency of TiO2 by Combining the Modification of Ag Nanoparticles with the Application of Anodic Bias 总被引:2,自引:0,他引:2
ChunHE YaXIONG DongSHU XiHaiZHU 《中国化学快报》2003,14(5):539-542
Ag-TiO2/TTO film electrode was used as photoanode to investigate the feasibility of a hybrid technology of Ag nanoparticles combined with the application of anodic bias.The results showed that the deposited Ag and applied anodic bias have an apparent additive effect. 相似文献
994.
A New Sesquiterpene Polyol Ester from Celastrus Angulatus 总被引:1,自引:0,他引:1
MingJianWU TianZengZHAO YuJunSHANG JingGuoFU HaiYanZHANG 《中国化学快报》2004,15(1):41-42
A new sesquiterpene polyol ester, angulatin D, has been isolated from the root bark of Celastrus angulatus. The chemical structure is elucidated on the basis of spectral analysis. 相似文献
995.
ChengBinCUI ChiXU QianQunGU ShiDongCHU HaiHongJI GangJING 《中国化学快报》2004,15(10):1191-1194
26-O-β-D-Glucopyranosyl-furost-5(6),20(22)-dien-3β,26-diol 1, a new furostanol saponin, was isolated from the water-extract of Dioscorea nipponica Mak., the raw material of a traditional Chinese herbal medicine Wei Ao Xin. The structure of 1 was determined on the basis of its spectral data especially by NMR spectroscopy. The result provides the first example of naturally occurring furostanol saponins with a single saccharide chain at the C-26 position. 相似文献
996.
997.
Qing Lin Jiang Li Hai Lei Chen Jiao Lu Zhi Rong Zhang Yong Wu 《中国化学快报》2008,19(2):127-129
A novel bifunctional glycolipid which carded a cluster of thiogalactosides as the hepatocyte targeting ligand for gene delivery was prepared. Hexa-antennary alcohol 1 was used as the core scaffold to attach a cholesterol molecule by a poly(ethylene glycol) chain, while its remaining branches were linked with five acetylgalactosides, which would be deacetylated later to produce pentaantennary galactoside. Liposome containing the galactoside showed high affinity and transfection activity in hepatoma cells HepG2. 相似文献
998.
Li PAN Xiao Feng ZHANG Hai Feng WU Li Sheng DING 《中国化学快报》2006,17(1):38-40
Daphne tangutica Maxim., a shrub of Thymelaeaceae family, meanly grows in northwest area of China at altitude of 1500-4000 m. The root barks of this plant are utilized as a traditional Tibetan medicine for releasing pain, curing rheumatism and as an abort… 相似文献
999.
Coordination studies on Zn(II) complexes of 1,3,5‐tri(2,5‐diazahexyl)benzene (L) show that by comparison with the non‐deprotonation of complex ZnL in a 1:1 system, the three‐dimensional complexiaton decreases the pKa of the Zn‐bound water molecule, that is, pKa = 7.47 for trinulclear complex Zn3L in a 3:1 metal–ligand ratio. These two types of zinc(II) complexes have been examined as catalysts for the hydrolysis of 4‐nitrophenyl acetate (NA) in 10% (v/v) CH3CN at 298 K, I = 0.10 mol dm?3 KNO3 at pH range 6.5–8.2 and 8.5–10, respectively. Kinetic studies show that the second‐order rate constants of NA‐hydrolysis catalyzed by complexes ZnL, Zn3L, and Zn3LH?1 are 0.021, 0.0082, and 0.342 mol?1 dm3 s?1, respectively. In all the cases, the pH‐dependent observed first‐order rate constant, kobs, shows sigmoidal pH–rate profile. The 1:1 complex ZnL–H2O undergoes NA hydrolysis by direct rate‐determining hydrolysis to produce 4‐nitrophenol(ate) (NP?) and ZnL(OOCCH3); while in the 3:1 system the oxygen atom of acetic group forms a H‐bond with the Zn(II)‐bound water of the second branch of tripod indicating that the polynuclear centers are associated and bi‐functional. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 36: 41–48 2004 相似文献
1000.
利用能量为 1 6 7— 1 75MeV的35Cl束流 ,通过16 0 Gd(35Cl,5n)熔合蒸发反应研究了190 Tl的高自旋态能级结构 .实验建立了190 Tl基于πh9/2 νi13/2 组态的转动带 .在束测量结果和194 Biα衰变的α γ测量结果确定地指定了190 Tl的πh9/2 νi13/2 转动带的自旋值 .基于自旋指定 ,发现了190 Tl的πh9/2 νi13/2 扁椭球转动带在低自旋时旋称反转 .这是首次在基于πh9/2 νi13/2 组态的扁椭球转动带中观测到旋称反转 .考虑了质子 -中子剩余相互作用的粒子 -转子模型能够解释πh9/2 νi13/2 扁椭球转动带的低自旋旋称反转 . 相似文献