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NUMERICAL SOLUTIONS OF REYNOLDS AVERAGED NAVIER-STOKES EQUATIONS FOR 3-D TURBULENT FLOW OVER CONCAVE SURFACES OF DISCHARGING STRUCTURES

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Journal of Hydrodynamics 2000年第4期12卷 120-126页

作者： wei wen-li li Jian-zhong Zhang Dong-sheng Xi′an University of Technology Xi′an 710048P.R.China

This paper is conserned with a numerical method for the solution of complete Reynolds averaged Navier Stokes equations for three dimensional flows over the concave surfaces of discharging structures. A non orthogonal body fitted coordinate system was used to deal with the complex physical geometry, and finite volume method (FVM) was employed to solve the convective transport equations for mean velocities and turbulence parameters (k, ε). It is indicated through the numerical example that the calculated results are in good agreement with the experimental ones, and it is also proved that this numerical method used to predict the characteristics of turbulent flow over the concave surfaces of discharging structures is feasible.

关键词： non-orthogonal body fitted coordinate system turbulent flow concave surface of discharging structure

SIMULATION OF STRONG TURBULENCE FLOW WITH FREE SURFACE INCLUDING THE EFFECTS OF STREAMliNE CURVATURE

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Journal of Hydrodynamics 2005年第5期17卷 629-635页

作者： DAI Hui-chao liU Yu-ling wei wen-li Institute of Water Conservancy and Hydraulic Engineering Hohai University Nanjing 210024 China China Yangtze River Three Gorges Project Development Corporation Yichang 443002 China Institute of Water Conservancy and Hydraulic Engineering Xi＇an University of Technology Xi＇ an 710048 China

This paper is concerned with a mathematical model for two-dimensional strong turbulence flow with free surface including the effects of streamline curvature in orthogonal curvilinear coordinate system, with which the characteristics of the turbulence flow field on the ogee spillway was numerical simulated. In the numerical simulation, the flow control equations in orthogonal curvilinear coordinate system were discretized by the finite volume method, the physical parameters（ P, U,V,K,ε,γt , etc. ） were arranged on a staggered grid, the discretized equations were solved with the SIMPLEC method, and the complex free surface was dealt with VOF method. The computed results show that the velocity fields, pressure field, shear stress distribution and kinetic energy of turbulent flow on the ogee spillway are in agreement with experimental data. This confirms that the model can be used for numerieal simulation of the turbulence flow on ogee spillway.

关键词： curvature correction turbulence model finite volume method free surface numerical simulation VOF method

Probing the redox process of p-benzoquinone in dimethyl sulphoxide by using fluorescence spectroelectrochemistry

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Frontiers of Environmental Science & Engineering 2017年第1期11卷 137-143页

作者： Rui Lu wei Chen wen-wei li Guo-Ping Sheng lian-Jun Wang Han-Qing Yu Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological Engineering Nanjing University of Science and Technology Nanjing 210094 China CAS Key Laboratory of Urban Pollutant Conversion Department of Chemistry University of Science and Technology of China Hefei 230026 China

Quinones are common organic compounds frequently used as model dissolved organic matters in water, and their redox properties are usually characterized by either electrochemical or spectroscopic methods separately. In this work, electrochemical methodology was combined with two fluorescence spectroelectrochemical techniques, cyclic voltafluorescence spectrometry （CVF） and derivative cyclic voltafluorescence spectrometry （DCVF）, to determine the electrochemical properties of p-benzoQuinone in dimethvl sulfoxide, an aprotic solution. The CVF results show that the electrochemical reduction ofp-benzoquinone resulted in the formation of radical anion and dianion, which exhibited a lower fluorescence intensity and red-shift of the emission spectra compared to that of p-benzoauinone. The fluorescence intensity was found to vary along with the electrochemical oxidation and reduction ofp-benzoquinone. The CVF and DCVF results were in good consistence. Thus, the combined method offers a powerful tool to investigate the electrochemical process of p-benzoquinone and other natural organic compounds.

关键词： p-Benzoquinone Electrochemistry Fluorescence Spectroelectrochemistry Derivative cyclic volta fluorescence

Ocular leech infestation initially misdiagnosed as conjunctival pigmented nevus

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International Journal of Ophthalmology(English edition) 2013年第4期6卷 557-558页

作者： wen-wei li Ting Shen Jin Jiang Department of Ophthalmology Zhejiang Provincial People's Hospital School of Ophthalmology and Optometry Wenzhou Medical College

Dear sir,Iam ***-wei li,from the Department of Ophthalmology,Zhejiang Provincial People’s Hospital,Hangzhou,China.I write to present a case of ocular leech infestation initially misdiagnosed as conjunctival pigmented... 详细信息

关键词： Ocular leech infestation initially misdiagnosed as conjunctival pigmented nevus body Figure

Fabrication of mesoporous lignin-based biosorbent from rice straw and its application for heavy-metal-ion removal

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Journal of Environmental Sciences 2017年第3期29卷 132-140页

作者： Fang Xu Ting-Ting Zhu qing-quan Rao Sheng-wen Shui wen-wei li Hong-Bo He Ri-Sheng Yao School of Medical Engineering Hefei University of TechnologyHefei 230009China CAS Key Laboratory of Urban Pollutant Conuersion Department of ChemistryUniversity of Science&Technology of ChinaHefei 230026China Environmental Monitoring Center of Taizhou Taizhou 31800China

lignocellulosic biomass offers the most abundant renewable resource in replacing traditional fossil resources. However, it is still a major challenge to directly convert the lignin component into value-added materials. The availability of plentiful hydroxyl groups in lignin macromolecules and its unique three-dimensional structure make it an ideal precursor for mesoporous biosorbents. In this work, we reported an environmentally friendly and economically feasible method for the fabrication of mesoporous lignin-based biosorbent （MLBB） from lignocellulosic biomass through a SOB micro-thermal-explosion process, as a byproduct of microcrystalline cellulose. BET analysis reveal the average pore-size distribution of 5.50 nm, the average pore value of 0.35 cm3/g, and the specific surface area of 186 m2/g. The physicochemical properties of MLBB were studied by fourier transform infrared spectroscopy （FTIR）, attenuated-total-reflection fourier transform infrared spectroscopy （ATR-FTIR）, X-ray photoelectron spectroscopy （XPS）, and element analysis. These results showed that there are large amounts of sutfonic functional groups existing on the surface of this biosorbent. Pb（II） was used as a model heavy-metal-ion to demonstrate the technical feasibility for heavy-metal-ion removal. Considering that lignocellulosic biomass is a naturally abundant and renewable resource and SO3 micro-thermal-explosion is a proven technique, this biosorbent can be easily produced at large scale and become a sustainable and reliable resource for wastewater treatment.

关键词： lignocellulosic biomassMesoporous biosorbentRice strawligninSulfur trioxideMicro-thermal-explosion

Metabolism Study on Tobacco-specific N-Nitrosamines in Rabbit by Solid-phase Extraction and liquid Chromatography-electrospray Ionization-mass Spectrometry Method

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Chinese Chemical Letters 2005年第12期16卷 1633-1636页

作者： Jian Xun ZHANG Chen Chen li Zheng CHEN Zhi Hua RAO Da wei wen Ke An li Hu wei liU College of Chemistry and Molecular Engineering Peking University Beijing 100871

Metabolism of four tobacco-specific N-nitrosamines （TSNAs）, N＇-nitrosonornicotine （NNN）, N＇-nitrosoanatabine （NAT）, N＇-nitrosoanabasine （NAB） and 4-（methyl nitrosamino）-1- （3-pyridyl）-1-butanone （NNK） was studied by solid-phase extraction （SPE） and liquid chromato- graphy-electrospray ionization-mass spectrometry （LC-ESI-MS）. SPE and LC-ESI-MS method was evaluated to be rapid, simple, sensitive and selective for analysis of TSNAs in rabbit serum. The doses of TSNAs administrated were 4.666 μg/kg and 11.665 μg/kg according to different levels in cigarettes. Metabolic curves of four TSNAs and 4-（methyl nitrosamino）-1-（3-pyridyl）- 1-butanone （NNAL）, the metabolite of NNK, were obtained.

关键词： Tobacco-specific N-nitrosamines metabolism liquid chromatography-electrosprayinterface-mass spectrometry

Preliminary optimization of a Chinese herbal medicine formula based on the neuroprotective effects in a rat model of rotenone-induced Parkinson's disease

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Journal of Integrative Medicine 2018年第4期16卷 290-296页

作者： Xu-xia Bao Hui-han Ma Hao Ding wen-wei li Min Zhu Department of Integrative Neurology Zhongshan HospitalFudan UniversityShanghai 200032China Institute of Neurology Institutes of Integrative Medicine of Fudan UniversityShanghai 200032China Shanghai Key Laboratory of Visual Impairment and Restoration Eye&ENT HospitalFudan UniversityShanghai 200030China

Objective： The main objective of this study was to preliminarily determine the optimum formulation of a Chinese herbal formula that may have neuroprotective effects against rotenone-induced Parkinson＇s disease （PD）. Methods： Seven recipes were made from Dihuang （DH, Rehmanniaglutinosa libosch）, Roucongrong （RCR, Cistanche deserticola ***）, Niuxi （NX, Achyranthes bidentata BI.） and Shanzhuyu （SZY, Comus officinalis Sieb. et Zucc） in different proportions, according to the principles of uniform design （4 factors 7 levels）. Tyrosine hydroxylase （TH）-positive neurons in substantia nigra pars compacta （SNpc） were detected by immunohistochemistry and rotenone-exposure days necessary to induce PD symptoms were recorded. To probe one likely mechanism of the formulas, echinacoside （ECH） concentrations of all seven recipes were determined by high-performance liquid chromatography and related to number of TH-positive neu- rons. Results： The data showed that recipe 4 （DH：RCR：SZY：NX = 1：1：1：1 ） and recipe 7 （DH：RCR：SZY：NX = 7：5：3： 1） partially reversed rotenone-induced death of TH-positive neurons in the SNpc and significantly increased rotenone-e^posed days compared with model group. Pharmacologically, there was not a strong correlation between ECH concentration and TH-positive neurons. Conclusion： The investigated formulations of Chinese herbs had neuroprotective effects against PD mod- els, and the neuroprotective effects were weakly related to the proportion of key herbs. However the neu- roprotective effects of the formula may not result from a single active constituent.

关键词： Parkinson's disease Rotenone Chinese herb Echinacoside Uniform design

Fluorescence Properties of Porphyrin Dimers Incorporating an Anhydride linker

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Chemical Research in Chinese Universities 2006年第6期22卷 684-687页

作者： FA Huan-bao YIN wei ZHENG wen-qi li Di SHAN Ning WANG Xing-qiao College of Chemistry Jilin University Changchun 130023 P. R. China

A preliminary study on a novel free base porphyrin dimer and a zinc prophyrin dimer by comparing their fluorescence properties with those of the corresponding monomers is presented. The fluorescence intensity of the free base dimer is five times higher than that of the monomer, but the fluorescence intensity of the zinc porphyrin dimer is nearly similar to that of the zinc porphyrin monomer. The emission spectra show that energy transfer occurs between the two units.

关键词： Porphyrin dimer Zinc dimer Fluorescence property

A Pt-Bi bimetallic nanoparticle catalyst for direct electro- oxidation of formic acid in fuel cells

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Frontiers of Environmental Science & Engineering 2013年第3期7卷 388-394页

作者： Shu-Hong li Yue ZHAO Jian CHU wen-wei li Han-Qing YU Gang liU Yang-Chao TIAN Department of Chemistry University of Science and Technology of China Hefei 230026 China National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230026 China

Direct formic acid fuel cells are a promising portable power-generating device, and the development of efficient anodic catalysts is essential for such a fuel cell. In this work Pt-Bi nanoparticles supported on micro-fabri- cated gold wire array substrate were synthesized using an electrochemical deposition method for formic acid oxida- tion in fuel cells. The surface morphology and element components of the Pt-Bi/Au nanoparticles were character- ized, and the catalytic activities of the three Pt-Bi/Au nanoparticle electrodes with different Pt/Bi ratios for formic acid oxidation were evaluated. It was found that Pt4Bi96/Au had a much higher catalytic activity than Pt11Bis89/Au and Pt13Bis87/Au, and Pt4Bi96/Au exhibited a current density of ***^-2, which was 27-times greater than that of Pt/Au. The electro-catalytic activity of the Pt-Bi/Au electrode for formic acid oxidation increased with the increasing Bi content, suggesting that it would be possible to achieve an efficient formic acid oxidation on the low Pt-loading. Therefore, the Pt-Bi/Au electrode offers a promising catalyst with a high activity for direct oxidation of formic acid in fuel cells.

关键词： catalyst electrochemical deposition formicacid oxidation fuel cell gold wire array microfabrication