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151.
Applicability of the angular properties of scatter elements as a tool to achieve improved slow light performance with small group velocity dispersion and large bandwidth in photonic crystal waveguides is investigated. A polyatomic photonic crystal waveguide, including two scatter elements with different geometrical shapes in each primitive cell, is proposed to investigate the feasibility of our method. Numerical results show that a versatile control of the dispersion relation of slow light modes, with large normalized delay-bandwidth products ranging from 0.2085 to 0.3394, can be obtained using a unique geometrical parameter. 相似文献
152.
An experimental study of mixed-convection heat and mass transfer flow of a CuS04 + H2S04 + H2O solution in a horizontal channel is performed by using an electrochemical system. Unstable temperature and concentration gradients imposed by a heated cathodic bottom initiate an ascending (secondary) flow of light boundary-layer fluid into the freestream. To visualize the flow, the shadowgraph technique is used. Electrical measurements are used to obtain mass transfer rates and to infer a Sherwood number. The ranges of the parameters studied in the present work for the square channel are Pr = 5-7, Sc = 1,700-2,300, Re = 100-1,000, Grm= 1.27 X 106 and Grab = 4.06 × 106-2.4S × 107. 相似文献
153.
Hou Conghui Zhang Hongfang Zheng Jianbin 《Journal of Solid State Electrochemistry》2017,21(10):3029-3035
Journal of Solid State Electrochemistry - This contribution described the electrochemical study of organosoluble gold nanoclusters (AuNCs).The AuNCs were characterized with UV-vis absorption... 相似文献
154.
Cheng-Ling Pan Chang-Min Hou Lei Zhang Yong Fan Shao-Ding Sheng 《Mendeleev Communications》2012,22(2):109-110
The reaction of potassium pyridyl amido ligand {L = [N(R)(2-C5H3N-6-Me)]–, R = CH2But} with YbI2(thf)2 afforded the linear polymeric complex [K0.5(L)3YbiiK0.5]n, which was characterized by X-ray structure analysis. 相似文献
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156.
Limin Yang Danqun Huo Kun He Suyi Zhang Changjun Hou 《Applied biochemistry and biotechnology》2013,170(4):909-924
Plant esterase extracted from wheat flour play key roles in the spectrophotometric detection of organophosphorus compounds (OPs) for food safety and human health. The purpose of the present study was to investigate the role of tryptophan residues in the activity and structure of plant esterase by chemical modification and fluorometric studies. Active site characterization of purified plant esterase showed the involvement of tryptophan in the catalytic activity. Only one was essential for the enzyme activity by the Tsou’s analysis. Substrate protection experiments further confirmed that the tryptophan residue was located at the substrate-binding site. Fluorescence quenching studies elucidated that the tryptophan residues were largely exposed to the solvent, and a smaller fraction of the surface tryptophan residues had electropositively charged amino acids around them. Experimental results obtained here are expected to promote the applications of plant esterase in OPs detection. Further confirmation of the existence of other critical residues and detailed explanation of their functions were also required for the elucidation of the mechanism involved in the detection of OPs. 相似文献
157.
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159.
Jiancong Du Suhui Deng Shangguo Hou Lingling Qiao Jianfang Chen Qing Huang Chunhai Fan Ya Cheng Yun Zhao 《中国光学快报(英文版)》2014,12(4):41101-38
DNA tetrahedral nanostructures are considered to be uew nanocarriers because they can be precisely controlled and hold excellent penetration ability to the cellular membrane. Although the DNA tetrahedral nanostructure is extensively studied in biology and medicine, its behavior in the cells with nanoscale resolution is not understood clearly. In this letter, we demonstrate superrcsolution fluorescence imaging of the distribution of DNA tetrahedral nanostructures in the cell with a simulated emission depletion (STED) microscope, which is built based on a conventional eonfocal microscope and can t)rovide a resolution of 70 nm. 相似文献
160.
Yuying Qu Yingchun Li Xiaoli Tan Weixiang Zhai Dr. Guifang Han Dr. Jingli Hou Prof. Guoquan Liu Prof. Yuguang Song Prof. Yangping Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(33):7888-7895
Tetrathiatriarylmethyl (TAM, trityl) radicals have found wide applications as spin probes/labels for EPR spectroscopy and imaging, and as polarizing agents for dynamic nuclear polarization. The high hydrophilicity of TAM radicals is essential for their biomedical applications. However, the synthesis of hydrophilic TAM radicals (e.g., OX063) is extremely challenging and has only been reported in the patent literature, to date. Herein, an efficient synthesis of a highly water-soluble TAM radical bis(8-carboxyl-2,2,6,6-tetramethylbenzo[1,2-d:4,5-d′]bis([1,3]dithiol-4-yl)-mono-(8-carboxyl-2,2,6,6-tetrakis(2-hydroxyethyl)benzo[1,2-d:4,5-d′]bis([1,3]dithiol-4-yl)methyl (TFO), which contains four additional hydroxylethyl groups, relative to the Finland trityl radical CT-03, is reported. Similar to OX063, TFO exhibits excellent properties, including high water solubility in phosphate buffer, low log P, low pKa, long relaxation times, and negligible binding with bovine serum albumin. On the other hand, TFO has a sharper EPR line and higher O2 sensitivity than those of OX063. Therefore, in combination with its facile synthesis, TFO should find wide applications in magnetic resonance related fields and this synthetic approach would shed new light on the synthesis of other hydrophilic TAM radicals. 相似文献