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Chinese Journal of Structural Chemistry 2007年第2期26卷 229-233页

作者： HAN xiang-yun ZHENG Qing Department of Chemical Engineering YanchengInstitute of Technology Jiangsu 224003 China

Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G^＊＊ level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna （-lgEC5o） was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients （lgKow）, dipole moment of the molecules（ μ） and entropy （S°）. For this equation, R^2 = 0.9582, q^2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

关键词： substituted biphenyl linear solvation energy theory,DFT method Daphnia magna toxicity

ABP41 is Involved in the Pollen Tube Development via Fragmenting Actin Filaments

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Molecular Plant 2008年第6期1卷 1048-1055页

作者： Ting Wang yun xiang Jian Hou Hai-yun Ren Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education Beijing Normal University Beijing 100875 People's Republic of China

ABP41 is identified as a novel member of plant villin/gelsolin/fragmin superfamily proteins from lily pollen, which binds stoichiometrically to actin filaments and severs them in vitro. To further understand its in-vivo function and the potential molecular mechanisms, biochemical analysis, fluorescence microscopic observation and microinjection assays were performed. Different biochemical measurements showed that ABP41 maintained actin filaments in forms of short F-actin in vitro. Microinjection of ABP41 into pollen tubes could fragment the pre-existing actin filaments, inhibit the velocity of cytoplasmic streaming, and shorten the length of the clear zone of pollen tube. In addition, it was found that the endogenous ABP41 expressing level was dynamically corresponding to the short actin filament structure in pollen at different stages of pollen germination. Our results suggest that ABP41 is involved in the regulation of actin dynamics during the pollen germination process via maintenance of short dynamic actin filaments.

关键词： ABP41 actin filament fragmentation pollen germination actin-binding protein.

Applications of An Eddy-Viscosity Eliminator Based on Sigmoid Functions in Reynolds-Averaged Navier-Stokes Simulations of Sloshing Flow

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China Ocean Engineering 2020年第4期34卷 463-474页

作者： LI Jin-long YOU yun-xiang CHEN Ke State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Yazhou Bay Institute of Deepsea Technology Shanghai Jiao Tong UniversitySanya 572000China

Reynolds-averaged Navier-Stokes(RANS)turbulence modeling can lead to the excessive turbulence level around the interface in two-phase flow,which causes the unphysical motion of the interface in sloshing *** order to avoid the unphysical motion of the interface,a novel eddy-viscosity eliminator based on sigmoid functions is designed to reduce the excessive turbulence level,and the eddy-viscosity eliminator based on polynomials is extracted from the cavitation *** elevations by combining the eddy-viscosity eliminators and classical two-equation closure models are compared with the experiments,the ones by using the adaptive asymptotic model(AAM)and the ones by using the modified two-equation closure *** root-mean-squared error(RMSE)is introduced to quantify the accuracies of surface elevations and the *** relation between the turbulence level in the transition layer and RMSEs of surface elevations is ***,the parametric analysis of the eddy-viscosity eliminators is carried *** studies suggest that(1)the excessive turbulence level in the transition layer around the interface has a significant influence on the accuracies of surface elevations and the forces;(2)the eddy-viscosity eliminators can effectively reduce the excessive turbulence level in the transition layer to avoid the unphysical motion of the interface;(3)the k-ωSST model combined with the eddy-viscosity eliminators is appropriate for predicting surface elevations and forces in RANS simulations of sloshing flow.

关键词： sloshing excessive turbulence level eddy-viscosity eliminator sigmoid function the unphysical motion of the interface

Outage analysis of opportunistic multi-antenna relay selection in decode-and-forward relay networks

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 6-12页

作者： WANG Xiao-xiang ZHENG Zi-yun Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This article studies the closed-form expressions of outage performance for opportunistic relay under aggregate power constraint in decode-and-forward （DF） relay networks over Rayleigh fading channels, assuming that multiple antennas are available at the relay node. According to whether instantaneous signal-to-noise ratio （SNR） or average SNR can be utilized for relay selection, two opportunistic relay schemes, opportunistic multi-antenna relay selection （OMRS） and average best relay selection （ABRS） are proposed. The performances of both two schemes are evaluated by means of theoretical analysis and simulation, it is observed that OMRS is outage-optimal among multi-antenna relay selection schemes and closely approaches the beamforming （BF） scheme known as theoretical outage-optimal. Compared with previous single-antenna opportunistic relaying （OR） scheme, OMRS brings remarkable performance improvement, which is obtained from maximum ratio combining （MRC） and beamforming techniques. It is also shown that the performance of ABRS in asymmetric channels is close to OMRS in the low and median SNR range.

关键词： relay selection multiple antennas multiple relays decode and forward cooperative networks

UNSTEADY INTERFACIAL WAVES DUE TO SINGULARITIES IN TWO SEMI-INFINITE INVISCID FLUIDS

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Journal of Hydrodynamics 2005年第6期17卷 730-736页

作者： LU Dong-qiang WEI Gang YOU yun-xiang The State Key Laboratory of Ocean Engineering Shanghai Jiaotong University Shanghai 200030 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai200030 China

The generation of unsteady interfacial gravity waves by a singularity immersed in two semi-infinite fluids was analytically investigated in detail by the methods of integral transform and of stationary-phase analysis. The fluids were assumed to be initially stationary, immiscible, inviscid and incompressible. The disturbed flows, generated by an impulsive and oscillatory source/dipole immersed above or be neath the interface, were governed by the *** equations. The kinematic and dynamic boundary conditions on the interface were linearized for the small-amplitude waves. By means of the stationary phase analysis on the exact integral form solutions, the asymptotic representations for the interracial waves were derived for large time with a fixed distance to time ratio. The relation between a submerged singularity and a sur face pressure point was discussed. It is found that the local wavelength and the local wave period of the interracial waves are elongated in comparison with those of free-surface waves for a single fluid.

关键词： interfacial waves singularity two-fluid system asymptotic representation

THE RADIATION AND DIFFRACTION OF WATER WAVES BY A BOTTOM-MOUNTED CIRCULAR CYLINDER IN A TWO-LAYER FLUID

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Journal of Hydrodynamics 2007年第1期19卷 1-8页

作者： YOU yun-xiang SHI Qiang MIAO Guo-ping School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China.

An analytical method was proposed to analyze the radiation and diffraction of water waves by a bottom-mounted circular cylinder in a two-layer fluid. Analytical expressions for added mass and damping coefficients, as well as the wave excitation forces of the circular cylinder were obtained by an eigenfunction expansion method. The hydrodynamic forces on the bottom-mounted circular cylinder in a two-layer fluid include not only the added mass and damping coefficients, but also the wave forces of the surface and internal-wave modes. This is different from the case of a homogenous fluid. Some examples were given, showing that density stratification can have a relative large effect on these hydrodynamic forces over a wide range of frequencies.

关键词： two-layer fluid bottom-mounted cylinder,surface-wave mode internal-wave mode hydrodynamic forces

Experimental, Numerical and Simplified Theoretical Model Study for Internal Solitary Wave Load on FPSO with Emphasis on Scale Effect

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China Ocean Engineering 2019年第1期33卷 26-33页

作者： ZHANG Rui-rui CHEN Ke YOU yun-xiang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Jiangsu University of Science and Technology

Scale effect of ISWs loads on Floating Production Storage and Offloading(FPSO) is studied in this paper. The application conditions of KdV, eKdV and MCC ISWs theories are used in the numerical method. The depthaveraged velocities induced by ISWs are used for the velocity-inlet boundary. Three scale ratio numerical models λ=1, 20 and 300 were selected, which the scale ratio is the size ratio of numerical models to the experimental *** comparisons between the numerical and former experimental results are performed to verify the feasibility of numerical method. The comparisons between the numerical and simplified theoretical results are performed to discuss the applicability of the simplified theoretical model summarized from the load experiments. Firstly, the numerical results of λ=1 numerical model showed a good agreement with former experimental and simplified theoretical results. It is feasible to simulate the ISWs loads on FPSO by the numerical method. Secondly, the comparisons between the results of three scale ratio numerical models and experimental results indicated that the scale ratios have more significant influence on the experimental horizontal forces than the vertical forces. The scale effect of horizontal forces mainly results from the different viscosity effects associated with the model’s ***, through the comparisons between the numerical and simplified theoretical results for three scale ratio models, the simplified theoretical model of the pressure difference and friction forces exerted by ISWs on FPSO is applied for large-scale or full-scale FPSO.

关键词： scale effect FPSO internal solitary wave numerical simulation simplified theoretical model

MECHANICAL AND THERMAL PROPERTIES OF NANOSIZED TITANIUM DIOXIDE FILLED RIGID POLY(VINYL CHLORIDE)

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Chinese Journal of Polymer Science 2013年第2期31卷 325-332页

作者： yun-xiang Zhang 宋义虎 Qiang Zheng Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education Department of PolymerScience and Engineering Zhejiang University

Nano-sized rod-like titanium dioxide （TiO2） filled rigid poly（vinyl chloride）（PVC） nanocomposites were prepared by using injection-molding method. Vicat, Charpy impact and tensile tests as well as thermogravimetric and dynamic mechanical analyses were used to characterize the structure and properties of the nanocomposites. The results showed that nano-TiO2 could improve Vicat softening temperature and also improve thermal stability of PVC during the stages of dehydrochlorination and formation of carbonaceous conjugated polyene sequences, which can be ascribed to restriction of the nanoparticles on the segmental relaxation as being evidenced by raises in glass transition and β-relaxation temperatures of PVC upon filling TiO2. Addition of TiO2 nanoparticles less than 40 phr （parts per hundreds of resin） could significantly improve impact strength of the composites while the TiO2 agglomeration at high contents leads to a reduction in impact toughness.

关键词： Poly(vinyl chloride) (PVC) Titanium dioxide (TiO2) Thermal property Mechanical property Impact strength.

Improvement analysis of article quality in World Journal of Gastroenterology during 2008-2012

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World Journal of Gastroenterology 2013年第44期19卷 7830-7835页

作者： Hua Yang yun-xiang Chen Library of Shengjing Hospital China Medical University

AIM:To understand the changes and development of World Journal of Gastroenterology(WJG)in recent ***:The Journal Citation Report(JCR)and SCI-E database of the ISI Web of Knowledge were used to search the articles and data of related indices in WJG during *** methods were used for statistical analysis of the author’s degree of collaboration,collaboration rate,the first author’s publications,high-productivity authors,the authors’origins in each year;the distribution of the countries and journals of the authors citing WJG papers was also *** addition,the indices related to this journal in each year were compared with the data from 6 SCI journals in the field of gastroenterology in the 2012 ***:A total of 4409 papers in WJG were examined in this *** the period 2008-2012,the selfcitation rate was 8.59%,6.02%,5.50%,4.47%and5.21%.Of a total of 3898 first authors,3526 published1 paper,291 published 2 papers,59 published 3 papers,and 22 published 4 or more *** origin of WJG authors covered the six continents,and the majority came from Asia,Europe and North *** number of countries of origin of WJG authors was65,66,61,65 an 60 for the period *** from 66 countries cited a total of 3194 of the 4409 papers,and these citations were found in 1140 ***:The results suggest that WJG has stayed on the track of normal international publication and all the indices of this journal are stable and reasonable.

关键词： Author analysis Bibliometrics World Journal of Gastroenterology Science Citation Index

Subacute toxicity of exogenous manganese on rat hippocampal neurons Examination by MRI and optical microscopy

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Neural Regeneration Research 2008年第5期3卷 550-553页

作者： Xiaoli Xu yun xiang Min Yang School of Medicine ＆ Life Science Jianghan University Wuhan 430056 Hubei Province China

BACKGROUND： Manganism may cause learning and memory impairment by influencing the normal function of the hippocampus, however, this effect requires further examination. OBJECTIVE： To investigate the effects of manganism on the rat hippocampus using immunohistochemistry and MRI examination. DESIGN, TIME AND SETTING： A randomized controlled study, performed in the School of Medicine and Life Science, Jianghan University and the State Key Laboratory of Atomic ＆ Molecular Physics and Spectroscopy, Chinese Academy of Science, from July to September 2005. MATERIALS： Fourteen healthy SD rats aged two months were selected for this study. MnCl2 4H2O （BHD, UK）（batch number： 9791325）; glial fibrillary acidic protein （GFAP） staining kit （Beijing Zhongshan Biotechnology）; Biospec 4.7T/30 animal MRI formatter （Bruker, Germany）. METHODS： Fourteen rats were randomly divided into a control group （n =7） and a manganism group （n = 7）. Rats in the manganism group received intraperitoneal injection of MnCl2 · 4H2O （50 mg/kg）, once a day, for four successive days. Rats in the control group were injected according to the manganism regimen, but using saline instead of manganese solution. MAIN OUTCOME MEASURES： Twenty-four hours after the last injection, rats were examined using MRI. Immunohistochemically stained GFAP and hematoxylin-eosin stained hippocampal sections were observed under optical microscopy. RESULTS： Fourteen rats were included in the final analysis. After manganese treatment, T1 weighted image and inversion recovery MR1 demonstrated that the signal intensity was significantly enhanced in hippocampus, compared to controls. Neuronal necrosis was not observed in the hippocampus after HE staining. As compared to the control group, GFAP expression was markedly enhanced in the hippocampus of the manganism group. CONCLUSION： Within the rat brain, manganese preferentially localizes to the hippocampus and can induce astroctye activation.

关键词： manganism hippocampus rats MRI glial fibrillary acidic protein