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Zhenshan Jia Xiang Zhang Gaihong Zhang Shaohua Huang Hao Fang Xiangqing Hu Yuliang Li Prof. Liangbing Gan Prof. Shiwei Zhang Prof. Daoben Zhu Prof. 《化学:亚洲杂志》2007,2(2):290-300
The Cs‐symmetric fullerene chlorohydrin C60(Cl)(OH)(OOtBu)4 reacts with 4‐dimethylaminopyridine (DMAP) and 1,4‐diazabicyclo[2.2.2]octane (DABCO) to yield two isomers with the formula C60(O)(OOtBu)4 in good yields. These isomers differ with respect to the location of the epoxy functionality. The one from DMAP is Cs symmetric, whereas that from DABCO is C1 symmetric with the epoxy group on the central pentagon. Two different mechanisms are proposed to explain the chemoselectivity of these reactions. The reaction with DMAP involves single‐electron transfer as the key step; DMAP acts as the electron donor. A combination of an oxygen‐atom shift and SN2′′ processes (boomerang substitution) are responsible for the formation of isomer with DACBO. Various related reactions support the proposed mechanisms. The structures of new fullerene derivatives were determined by spectroscopy, single‐crystal X‐ray analysis, and chemical correlation experiments. 相似文献
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A sandwiched structure of CdS/Ag/ZnO nanorod photoanode exhibits greatly enhanced photoelectrochemical activity for solar hydrogen generation, due to synergistic effect of CdS nanocrystallites and plasmonic Ag nanoparticles for the enhanced optical absorption and the promoted charge carrier separation. 相似文献
15.
Two new Schiff bases (SMPDH and SBPDH) of S-methyl- and S-benzyl-dithiocarbazate with 2-pyridinecarboxaldehyde N-oxide were prepared and confirmed by elemental analyses and IR spectra. Four copper(II) complexes of the above two Schiff base ligands with imidazole and pyridine were obtained and characterized spectroscopically. The crystal structure of [Cu(SMPD)ImH]ClO4 was determined by X-ray diffraction analysis. The geometry of the copper atoms in these complexes is square planar with an unsymmetrical environment. 相似文献
16.
Sheng Yang Antonio Gaetano Ricciardulli Dr. Shaohua Liu Dr. Renhao Dong Dr. Martin R. Lohe Alfons Becker Marco A. Squillaci Prof. Paolo Samorì Prof. Klaus Müllen Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2017,56(23):6669-6675
To bridge the gap between laboratory-scale studies and commercial applications, mass production of high quality graphene is essential. A scalable exfoliation strategy towards the production of graphene sheets is presented that has excellent yield (ca. 75 %, 1–3 layers), low defect density (a C/O ratio of 21.2), great solution-processability, and outstanding electronic properties (a hole mobility of 430 cm2 V−1 s−1). By applying alternating currents, dual exfoliation at both graphite electrodes enables a high production rate exceeding 20 g h−1 in laboratory tests. As a cathode material for lithium storage, graphene-wrapped LiFePO4 particles deliver a high capacity of 167 mAh g−1 at 1 C rate after 500 cycles. 相似文献
17.
Jia Yu Fu Zheng Qiang Gao Yinjie Li Yungang Zhang Zhiguo Zhang Shaohua Wu 《Applied physics. B, Lasers and optics》2014,116(1):135-140
A simple cubic-shaped cavity with a high-diffuse-reflectivity inner coating as a novel gas detection cell was developed. The effective optical path length (EOPL) was evaluated by comparing the oxygen absorption signal in the cavity and in air based on tunable diode laser absorption spectroscopy. The law for a spherical cavity was applied and modified to a cubic cavity as a function of reflectivity ρ, port fraction f, and the side length. Single-pass average path length of the cubic cavity was 0.723(7) times the side length. EOPL can be modified conveniently by adjusting the parameters of the cavity. 相似文献
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Frontispiece: Irreversible Denaturation of Proteins through Aluminum‐Induced Formation of Backbone Ring Structures
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19.
This paper is a consequence for a paper of Lin et al. [S.W. Lin, Y.W. Wou, P. Julian, Note on minimax distribution free procedure for integrated inventory model with defective goods and stochastic lead time demand, Appl. Math. Model. 35 (2011) 2087–2093]. We simplified their complicated solution procedure and then presented a revision to patch their negligence for the boundary minimums. Numerical examples are provided to demonstrate our findings. 相似文献
20.
A novel chiral 1,2-diaminocyclohexane derivative, (1R,2R)-N1-n-pentyl, N1-benzyl-1,2-cyclohexanediamine, was designed, synthesized and applied as a catalyst in a number of aldol reactions between ketones and aryl aldehydes. Reactions between acetone and aryl aldehydes gave aldol products with moderate to good yields and with excellent enantioselectivity (up to yield 85%, ee 98%), while reactions between cyclohexanone and aryl aldehydes provided anti-β-hydroxyketone products with excellent yields, diastereoselectivity and with enantioselectivity (up to 82% yield, anti/syn ratio 99:1, ee 99%). The aldol reactions between acetone and isatins were investigated, which afforded excellent yields and enantioselectivity (up to 95% yield, 98% ee). The (R)- and (S)-isomers of convolutamydine A were obtained with 95% yield and 96% ee, and 95% yield and 94% ee, respectively. 相似文献