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Journal of Hydrodynamics 2007年第1期19卷 18-22页

作者： ZHANG Cheng ZHUANG Li-Xian LU Xi-Yun Department of Mechanics and Mechanical engineering University of Science and Technology of China Hefei 230026 China

Hydrodynamic characteristics for two-dimensional flow around a waving plate are investigated. Under large Reynolds number approximation, the flow is assumed to be a combination of the outer potential flow and a thin vortex layer, which consists of a boundary layer and a shed free shear layer. A nonlinear mathematical formulation for describing the outer unsteady potential flow coupled with an unsteady boundary layer equation for the inner viscous flow adjacent to the waving plate is developed. A semi-analytical method with a nonlinear Kutta condition imposed at the trailing edge is used to solve the velocity field of the outer flow and the evolution of wake vortex induced by a large-amplitude waving plate. The unsteady boundary layer equation is solved by extending Pohlhausen＇s method to its unsteady counterpart. The thrust and viscous drag coefficients, propulsive efficiency, and the pattern of wake vortex sheet are discussed.

关键词： waving plate fish swimming unsteadyboundary layer vortex shedding

Neutral sulfate berberine modulates cytokine secretion and increases survival in endotoxemic mice

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Acta Pharmacologica Sinica 2006年第9期27卷 1199-1205页

作者： Fei LI Hua-dong WANG~2.Da-xiang LU Yan-ping WANG Ren-bin QI Yong-mei FU Chu-jie LI Department of Pathophysiology,Medical college of Jinan university,Guangzhou 510632.{2. Department of Pathophysiology Medical College of Jinan University Guangzhou China

Aim:Berberine is thought to be an immunomodulator,so the present study aimedto investigate the effect of berberine on mortality,lung and intestine injury inendotoxemic mice,and the mechanism of its ***:Mice were chal-lenged with lipopolysaccharide(LPS,2. mg/kg,ip),and neutral sulfate berbefinewas administrated *** was monitored every 12.h,and his-tology of the lungs and intestine as well as the plasma tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ),interleukin-12.IL-12.,IL-10,and nitric oxide(NO)levels were ***:Pretreatment with 50 mg/kg neutral sulfate ber-berine once a day for 5 days significantly decreased the mortality rate and attenu-ated tissue injury of the lungs and small intestine in mice challenged with *** stimulated a marked increase in plasma levels of TNF-α,IFN-γ,IL-12.IL-10,and *** administration of berberine significantly reduced plasma TNF-α,IFN-γ,and NO levels,but did not suppress plasma IL-12.levels in mice exposed ***,pretreatment with neutral sulfate berbefine augmented IL-10secretion stimulated by LPS in ***:Pretreatment with neutral sul-fate berberine attenuates tissue injury and improves survival in endotoxemic mice,which may be mediated,at least in part,by the inhibition of pro-inflammatorymediator production and upregulation of IL-10 *** findings mightprovide a new strategy for the treatment of endotoxemia.

关键词： lipopolysaccharide berberine tumor necrosis factor-α interleukin-10 interleukin-12 interferon-γ nitric oxide mice

循环流化床煤燃烧/热解双反应器压力分布的实验研究

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燃料化学学报 2004年第4期32卷 413-417页

作者：王志锋梁鹏董众兵毕继诚中国科学院山西煤炭化学研究所煤转化国家重点实验室

实验测量了一种新型的循环流化床煤燃烧/热解冷模反应器中提升管及立管内的压力分布,其中提升管的内径为100mm、高为6m;立管内径为44mm、高为3m,热解室的截面为2.0mm×2.0mm、高为770mm。分别考察了提升管内的表观气速Ur、循环量Gs、加... 详细信息

实验测量了一种新型的循环流化床煤燃烧/热解冷模反应器中提升管及立管内的压力分布,其中提升管的内径为100mm、高为6m;立管内径为44mm、高为3m,热解室的截面为2.0mm×2.0mm、高为770mm。分别考察了提升管内的表观气速Ur、循环量Gs、加到热解室内的松动气量Qa以及初始装料量G等对系统压力分布的影响。结果表明,在立管底部阀门开度不变的情况下随着Ur的增加,提升管及立管内的压力梯度都趋于减小;在提升管内表观气速一定的情况下随着循环量Gs的增加,提升管及立管内的压力分布也随之增大;加到热解室内的松动气对立管内的压力分布影响较大,而对提升管内的压力分布影响相对较小;在立管底部阀门开度及Ur一定的情况下,随着初始装料量的增加提升管及立管内的压力分布也趋于增大。

关键词：循环流化床煤热解提升管立管压力分布

Transformation of organic matters in fresh leachate during anaerobic degradation under long hydraulic retention time

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Journal of Environmental sciences 2009年第9期21卷 1302-1308页

作者： XU Suyun,HE Pinjing,LU Fan,LI Min,SHAO Liming State Key Laboratory of Pollution Control and Resources Reuse,Key Laboratory of Yangtze River Water Environment,college of Environmental science and {2.,Tongji university,Shanghai 2.0092.china State Key Laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongji University Shanghai 200092 China

This study investigated the biodegradability of fresh leachate from a young municipal solid waste landfill at the inoculum to substrate ratios （V/V） of 10/100, 2./100, 50/100 and 100/100, as well as the transformation of organic matters in leachate under prolonged hydraulic retention time （HRT） of 50 d. Fresh leachate showed a good biodegradability, with chemical oxygen demand （COD） removal efficiency as high as 87%-92. and cumulative methane yield close to theoretical value （0.35 L CH4/g CODdeg）. Methane production and COD depletion presented biphasic characteristics associated with the successive utilization of two major intermediates, acetate and propionate, The biphasic degradation of fresh leachate was resulted from the different hydrolysis rates of diverse substrates and the changes in microorganism community structure. After 50 d, the effluents were dominated by high-MW organic compounds （MW 〉 10 kDa） at each inoculum ratio, which might be refractory compounds released from cell lyses.

关键词： biodegradability biomass lyses methane production ratio of inoculum to substrate volatile fatty acids

Photothermal effect in the tissue during photodynamic therapy

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Photothermal effect in the tissue during photodynamic therap...

Systematic study of the transfer of amino acids across the water/1,2.dichloroethane interface facilitated by dibenzo-18-crown-6

2.th Congress of the International Commission for Optics

作者： LI Zhongming1,2. ZHANG Zhenxi1 (1. The Key Laboratory of Biomedical Information engineering of Ministry of Education, School of Life science and {2., Xi’an Jiaotong university, Xi’an, Shanxi, 710049, china 2. School of Information engineering, Xianning university, Xianning, Hubei, 437005, china )

Based on the Pennes’ bio-heat transfer equation, temperature distribution in the tissue during PDT is analyzed in theory. The study indicates that laser heat source could be formed in tissue during la

关键词： Photodynamic therapy Light dosage Photothermal interaction effect Theoretic analysis

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science china Chemistry 2004年第1期47卷 24-33页

作者： CHEN Yong, YUAN Yi, ZHANG Meiqin, LI Fei, SUN Peng, GAO Zhao & SHAO YuanhuaState Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of sciences, Changchun 13002., china {2. of Chemistry and Molecular engineering, Peking university, Beijing 100871, china Lab. of Electroanalytical Chem. Changchun Inst. of Appl. Chem. Chinese Acad. of Sci. Changchun 130022 China Coll. of Chem. and Molecular Eng. Peking Univ. Beijing 100871 China

Facilitated ion transfer reactions of 2. amino acids with dibenzo-18-crown-6 (DB18C6) at the water/1,2.dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, lie, Phe, Trp, Met, Ala, Gly, Cys, Gin (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (β0), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively. The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization. Moreover, the association constants and the standard rate constants for different amino acids showed good correlations with their hydrophobicity (π), except Gly and Met, which inferred that the selectivity of such heterogeneous complex reaction for different amino acids with DB18C6, was not only affected by discrimination in binding these ions to the crown ether macro-cycle, but also significantly modified by the ion transfer Gibbs energy which was closely related to the structure of the transferred ions, protonated amino acids.

关键词： micro-/nano-pipet, water/1,2.dichloroethane interface, facilitated ion transfer, cyclic voltammetry, amino acid.

Rapid Prototyping Bipolar Plate of PEMFC by Gelcasting

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Rapid Prototyping Bipolar Plate of PEMFC by Gelcasting

Conservation laws of some soliton equations with self-consistent sources

第七届全国氢能学术会议

作者： LUO Bing, CHEN Shang-wei, HUANG Mmg-yu, WANG Lian-jun (School of Chemical engineering, nanjing {2. of science & technology, nanjing 2.0094,china School of Automobile, Jiangsu {2., Zhenjiang 2.2.13,china School of Mechanical engineering, Nantong {2., Nantong 2.6007,china)

Bipolar plate is one key component of proton exchange membrane fuel cell (PEMFC) . According to this paper, mesocarbon microbeads were used as raw materials for forming the green bodies of bipolar plates with complex flow channels by gelcasting technique. Then, the final bipolar plates would be gained after the green parts were died, burned out and sintered. Meanwhile, its properties arc researched and evaluated by the test of flexible strength and electric resistivity。The resultant flexural strength of sintered sample is 67 MPa and the electric resistivity is 52.Ω·m.

关键词： PEMFC bipolar plate mesocarbon microbeads (MCMB) gelcasting

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Journal of Shanghai university(English Edition) 2011年第3期15卷 157-165页

作者：李琪张大军陈登远 Department of Mathematics College of Sciences Shanghai University Department of Mathematics East China Institute of Technology

Infinitely many conservation laws for some （1＋1）-dimension soliton hierarchy with self-consistent sources are constructed from their corresponding Lax pairs directly. Three examples are given. Besides, infinitely many conservation laws for Kadomtsev-Petviashvili （KP） hierarchy with self-consistent sources are obtained from the pseudo-differential operator and the Lax pair.

关键词： Ablowitz-Kaup-Newell-Segur (AKNS) hierarchy with self-consistent sources Kaup-Newell (KN) hierarchy with self-consistent sources Ablowitz-Ladik (AL) hierarchy with self-consistent sources Kadomtsev-Petviashvili (KP) hierarchy with self-consistent sources conservation laws

Research progress in studies on the coalbed gas geochemistry

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Progress in Natural science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (college of Resources sciences & {2., Beijing Normal university, Beijing 100875, china Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of sciences, Lanzhou 730000, china) college of Resources sciences and {2. Beijing Normal University Beijing 100875 China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13C1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4 values available for utilization vary from - 333‰ to - 117‰, and δ13CCO2.values from - 2.. 4‰ to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13C1 and δ13CCO2.values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13C1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.