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711.
Pengfei Zhao Miaoduo Deng Peiting Huang Jia Yu Xingjie Guo Longshan Zhao 《Analytical and bioanalytical chemistry》2016,408(23):6381-6392
712.
Zourab Brodzeli Andrew Michie Qi Guo Evgeny P. Pozhidaev Vladimir Chigrinov 《Liquid crystals》2013,40(10):1427-1435
We present a detailed theoretical and experimental study of the reflectance response of a deformed-helix ferroelectric (DHF) liquid crystal (LC) cell to an applied voltage under cross-polarisers. Using a model based on the effective dielectric tensor approximation, we derive simple analytical formulas to design a LC cell with maximum modulation depth and optimal linearity of the electro-optical response intensity versus the electric field. Our experimental results show that the cell works at frequencies up to 10 kHz and exhibits excellent linearity, with a total harmonic distortion as low as ?70 dB. These findings suggest that DHF-LCs can be exploited to develop simple and accurate optical sensors. 相似文献
713.
714.
715.
Cover Picture: Open‐Pore Two‐Dimensional MFI Zeolite Nanosheets for the Fabrication of Hydrocarbon‐Isomer‐Selective Membranes on Porous Polymer Supports (Angew. Chem. Int. Ed. 25/2016)
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Han Zhang Prof. Qiang Xiao Prof. Xianghai Guo Prof. Najun Li Prashant Kumar Neel Rangnekar Mi Young Jeon Prof. Shaeel Al‐Thabaiti Prof. Katabathini Narasimharao Prof. Sulaiman Nasir Basahel Prof. Berna Topuz Frank J. Onorato Prof. Christopher W. Macosko Prof. K. Andre Mkhoyan Prof. Michael Tsapatsis 《Angewandte Chemie (International ed. in English)》2016,55(25):7009-7009
716.
Crystal structure of meso‐substituted pyrazolyl porphyrin complexes and their highly active catalyst for oxidation of alkylbenzenes
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During the past few years, a great deal of effort has been devoted to the anchoring of catalytic oxidation. In this work, three new catalysts CuPp, MnPp and ZnPp by solvothermal methods with 5, 10, 15, 20‐tetrakis(4‐N‐pyrazolyl)‐phenyl porphyrin (H2Pp) and the corresponding metal salts have been synthesized and structurally characterized. The single crystal structures determined by X‐ray diffraction show the bond distances of M‐N in porphyrin cores determined the conformation of porphyrin rings. We explored the catalytic activity of CoPp, CuPp, MnPp and ZnPp for oxidation of alkylbenzenes. The experimental results display these products exhibit high catalytic activities and selectivities for oxidation of ethylbenzene to acetophenone, and can be reused by filtration without appreciable decrease in catalytic activity and selectivity. 相似文献
717.
Meng-Yue Guo Gen Li Shuai-Liang Yang Ran Bu Xian-Qing Piao Prof. En-Qing Gao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(66):16415-16421
The assembly of two tripyridinium-tricarboxylate ligands and different metal ions leads to seven isostructural MOFs, which show novel 2D→2D supramolecular entanglement featuring catenane-like interlocking of tricyclic cages. The MOFs show tripyridinium-afforded and metal-modulated photoresponsive properties. The MOFs with d10 metal centers ( 1-Cd , 1-Zn , 2-Cd , 2-Zn ) show fast and reversible photochromism and concomitant fluorescence quenching, 1-Ni displays slower photochromism but does not fluoresce, and 1-Co and 2-Co are neither photochromic nor fluorescent. It is shown here that the network entanglement dictates donor-acceptor close contacts, which enable fluorescence originated from interligand charge transfer. The contacts also allow photoinduced electron transfer, which underlies photochromism and concomitant fluorescence response. The metal dependence in fluorescence and photochromism can be related to energy transfer through metal-centered d-d transitions. In addition, 1-Cd is demonstrated to be a potential fluorescence sensor for sensitive and selective detection of UO22+ in water. 相似文献
718.
Junfu Guo Wei Zhou Pengfei Xing Peiqing Yu Qinggong Song Ping Wu 《Solid State Communications》2012,152(11):924-928
The electronic structural, magnetic and optical properties of pure and V-doped ZnO are investigated by first-principles calculations based on the density functional theory. With the introduction of V atoms, the spin-splitting near the Fermi level leads to a net magnetic moment of the system. A significant possibility of room temperature ferromagnetism (RTFM) originated from the Ruderman–Kittel–Kassuya–Yosida (RKKY) exchange is predicted. Oxygen vacancy is positive to enhance the ferromagnetism while zinc vacancy is negative. With respect to the optical properties, the presence of V atoms was found to have an obvious influence on the transmittivity, especially in the low energy region. A slight V-doping can keep a high optical transmission and smoothly modulate the optical bandgap. 相似文献
719.
Dr. Yong Guo Dr. Wengang Li Dr. Jingjing Yan Dr. Basem Moosa Dr. Ma'an Amad Prof. Charles J. Werth Prof. Niveen M. Khashab 《化学:亚洲杂志》2012,7(12):2842-2847
Metal‐free fullerene (C60) was found to be an effective catalyst for the reduction of azo groups in basic aqueous solution under UV irradiation in the presence of NaBH4. Use of NaBH4 by itself is not sufficient to reduce the azo dyes without the assistance of a metal catalyst such as Pd and Ag. Experimental and theoretical results suggest that C60 catalyzes this reaction by using its vacant orbital to accept the electron in the bonding orbital of azo dyes, which leads to the activation of the N?N bond. UV irradiation increases the ability of C60 to interact with electron‐donor moieties in azo dyes. 相似文献
720.
Xie Puhui Zhu Yanru Huang Xuewei Gao Guangqin Guo Fengqi Yang Guoyu 《Research on Chemical Intermediates》2018,44(4):2823-2837
Research on Chemical Intermediates - A new near-infrared fluorescent “turn-on” chemodosimeter (probe 1) based on dicyanomethylene-4H-chromene fluorophore for sulfide was developed.... 相似文献