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991.
Pei Nian Liu Dr. Fu Hai Su Dr. Ting Bin Wen Dr. Herman H.‐Y. Sung Dr. Ian D. Williams Prof. Dr. Guochen Jia Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(26):7889-7897
The new ruthenium complex [Ru(N3P)(OAc)][BPh4] ( 4 ), in which N3P is the N,P mixed tetradentate ligand N,N‐bis[(pyridin‐2‐yl)methyl]‐[2‐(diphenylphosphino)phenyl]methanamine was synthesized. The complex was found to be catalytically active for the endo cycloisomerization of alkynols. The catalytic reactions can be used to synthesize five‐, six‐, and seven‐membered endo‐cyclic enol ethers in good to excellent yields. A catalytic cycle involving a vinylidene intermediate was proposed for the catalytic reactions. Treatment of complex 4 with PhC?CH and H2O gave the alkyl complex [Ru(CH2Ph)(CO)(N3P)][BPh4] ( 30 ), which supports the assumption that the catalytic reactions involve addition of a hydroxyl group to the C?C bond of vinylidene ligands. 相似文献
992.
Jiefeng Rong Yuwu Chi Yuanjin Zhang Lichan Chen Guonan Chen 《Electrochemistry communications》2010,12(2):270-273
A hydrophobic thiol-functionalized ionic liquid (IL) was synthesized and immobilized tightly on a gold electrode surface via Au–S bond to construct a stable Au–IL|water interface. At the Au–IL|water interface, the electrochemiluminescence (ECL) of luminol-O2 system was investigated. The ECL intensity of luminol-O2 system at the Au–IL|water interface was much larger and more stable than that at Au|water interface. The enhanced ECL mechanism at the Au–IL|water interface was studied and discussed in details. 相似文献
993.
994.
Pt-doped mesoporous indium oxide (In2O3) has been successfully obtained by a simple and effective in situ nanocasting method. The resultant samples were characterized by XRD, FE-SEM, TEM, N2 physisorption, XPS and EDX. The gas sensing properties for hydrogen sulfide (H2S) of the Pt-doped mesoporous In2O3 specimens were also examined. The results exhibit those In2O3 specimens possess much higher response to H2S even at low concentration of 2 ppm and a lower optimum working temperature of 150 °C. A possible mechanism was also provided to explain the improvement of the sensing properties. 相似文献
995.
Stephen A. Morin Young‐Hye La Dr. Chi‐Chun Liu Jeremy A. Streifer Dr. Robert J. Hamers Prof. Paul F. Nealey Prof. Song Jin Prof. 《Angewandte Chemie (International ed. in English)》2009,48(12):2135-2139
Growing in line: The surface chemistry of self‐assembled nanostructured block copolymers is used to control the sites at which semiconducting metal sulfide nanocrystals nucleate and grow on a surface directly from aqueous solutions. This process is a new and general strategy for the bottom‐up assembly of functional nanocrystalline materials for a variety of applications.
996.
A systematic study of various metal trifluoromethanesulfonates as efficient catalysts in the regioselective reductive ring opening of benzylidene acetals is described, including the effects of solvents, reducing agents, and temperature. These catalysts are found to be effective in cleaving the 4,6‐O‐acetal rings of hexopyranosides at either O4 or O6, respectively. When used in conjunction with a 1 M solution of BH3·THF in THF without extra addition of any solvent, it affects the ring fission at the O6 position to generate the corresponding primary alcohols, whereas O4‐opening takes place in acetonitrile in the presence of dimethylethylsilane as the reductant leading to the secondary hydroxyl derivatives in high selectivity and yields. These methodologies can be applied to a wide range of substrates containing various functional groups. 相似文献
997.
Chi Honn Cheng 《Journal of Mathematical Analysis and Applications》2009,352(2):724-732
The study of Cauchy problem of the Boltzmann equation is important in both theory and applications. Existence of global solutions to the equation and uniform stability of solutions in the absence of external force were introduced in the previous work on the Boltzmann equation. In this paper, we will investigate the uniform stability of solutions in L1 for the Cauchy problem of the Boltzmann equation when there is an external force for the case of soft potentials. 相似文献
998.
该文利用k- 集压缩算子抽象连续性定理和一些分析技巧研究了一类具有偏差变元的二阶泛函微分方程周期解的存在性. 该文的结果推广和改进了文献[1-2]的主要结果. 相似文献
999.
Characterization methods for bulk non-centrosymmetric compounds are described. These methods include second-harmonic generation, piezoelectricity, pyroelectricity, and ferroelectricity. In this tutorial review with each phenomenon, details are given of the measurement techniques along with a brief history and background. Finally, data interpretation is discussed. 相似文献
1000.
Wu X Lenhert S Chi L Fuchs H 《Langmuir : the ACS journal of surfaces and colloids》2006,22(18):7807-7811
High-quality CdTe nanoparticles stabilized with thioglycolic acid (TGA) are patterned on SiO2/Si surfaces using microcontact printing (microCP). Due to the weak interaction of the nanoparticles with the stamp surface, tailoring of gas flow rate during the inking process as well as the type and scale of the patterns on the stamp are used to control the distribution of the nanoparticles on the structured stamp surface. This distribution is then transferred the printed regions. Either edge printing or homogeneous printing can be achieved under optimized conditions. In addition, new structures such as nanowires form under certain conditions. 相似文献