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WAVE-BODY INTERACTIONS FOR A SURFACE-PIERCING BODY IN WATER OF FINITE DEPTH

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Journal of Hydrodynamics 2010年第6期22卷 745-752页

作者： LI Yong lin mian Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

Nonlinear wave-body interactions for a stationary surface-piercing body in water of finite depth with fiat and sloping bottoms are simulated in a two-dimensional numerical wave tank, which is constructed mainly based on the spatially averaged Navier-Stokes equations with the k- ε model for simulating the turbulence. The equations are discretized based on the finite volume method and the scheme of the pressure implicit splitting of operators is employed to solve the Navier-Stokes equations. By using the force time histories, the mean and higher-harmonic force components are calculated. The computational results are shown to be in good agreement with experimental and numerical results of other researchers. Then, the horizontal force, the vertical force and the moment on the surface-piercing body under nonlinear regular waves with flat and sloping bottoms are obtained. The results indicate that the bottom topographies have a significant influence on the wave loads on the surface-piercing body.

关键词： wave-body interaction surface-piercing body numerical wave tank finite water depth

A dynamic coupling numerical model for pollutant transport under wave condition

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Acta Mechanica Sinica 2015年第1期31卷 53-61页

作者： Yong Li mian lin Zhen Wang Institute of Mechanics Chinese Academy of Sciences

In order to study the diffusion, migration, and distribution of pollutants among overlying waterbody and porous seabed under wave conditions, a dynamic coupling numerical model is proposed. In this model, the coupling between wave field of overlying waterbody and seepage of porous bed, the capture and release of pollutants in porous media, and the transport process between the two different regions are taken into account. We use the unified equa tions for pressure correction and pollutant concentration to solve the numerical model, which avoids repeated iteration on the interface boundary. The model is verified by several case studies. Afterwards, the processes involving release of pollutant from porous seabed and transportation to overly ing waterbody under different wave conditions are investi gated. The results show that the water depth, wave height, and wave period have great influences on the release, cap ture, and transport processes for phosphorus pollutant.

关键词： Wave Pollutant Transport process Dynamiccoupling model Numerical analysis

Numerical simulation of the dynamic migration mechanism and prediction of saturation of tight sandstone oil

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Science China Earth Sciences 2024年第1期67卷 179-195页

作者： Gaohui CAO mian lin Likuan ZHANG Lili JI Wenbin JIANG Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

Quantitative characterization of tight sandstone oil migration and accumulation is an emerging research frontier in the field of oil and gas *** this study,a conceptual model containing multiple basic geological elements is developed,and a nonlinear seepage numerical model for tight sandstone oil migration and accumulation is *** effects of the slip effect,overpressure driving force,buoyancy,and capillary force on the migration and accumulation of tight oil are *** results showed that(1)the differences in oil migration and accumulation between tight and conventional reservoirs are reflected in the growth mode of oil saturation,distribution characteristics of oil and water,and extent of the effect of the formation dip angle;(2)the slip effect has a significant impact when the average pore throat radius is less than 150 nm and the overpressure driving force and capillary force are the main mechanical mechanisms controlling oil migration and accumulation in tight sandstone,while the coupling effect of buoyancy,capillary force,and overpressure driving force controls the upper and lower limits of oil ***,a dimensional and dimensionless identification chart for rapidly predicting the oil saturation of tight sandstone is proposed and verified using the measured *** study provides a basis for analyzing the migration and accumulation mechanisms of tight sandstone oil and a new approach for predicting oil ***,we developed digital and visual analysis methods for the migration results,enriching the expression of the dynamics of hydrocarbon accumulation.

关键词： Tight sandstone Migration and accumulation Dynamics Oil saturation Numerical simulation

Monoterpene and tetrahydronaphthene derivatives from Senecio argunensis

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Chinese Chemical Letters 2009年第5期20卷 598-600页

作者： Chao Feng Zhang Ning Li lin Li mian Zhang Research Department of Pharmacognosy China Pharmaceutical University Nanjing 210038 China

Two new compounds, senarguines A and B, were isolated from Senecio argunensis. They were respectively identified as （Z）-3- ethylidene-9-hydroxyl-9-methyl-6,7-dioxaspiro [4.4] nonane-5,8-dione （1） and 3,6,6-trimeth... 详细信息

关键词： Compositae Senecio argunensis Senarguine A Senarguine B

PROCESS CONTROL OF THE SAND WAVE MIGRATION IN BEIBU GULF OF THE SOUTH CHINA SEA

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Journal of Hydrodynamics 2011年第4期23卷 439-446页

作者： LI yong lin mian JIANG Wen-bing FAN Feng-xin Institute of Mechanics Chinese Academy of Sciences Beij ing 100190 China Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Based on the environment characteristics of the Beibu Gulf of South China Sea, a quasi-three-dimensional physical model is built. By coupling the bottom boundary layer with the two-dimensional tidal current field near the seabed surface, the quasi-three-dimensional hydrodynamic numerical simulation is carried out. The sand wave migration process is dealt with by coupling the hydrodynamic model with the sediment transport model. The computational results are shown to be in good agreement with the observed data, which indicates that the quasi-three-dimensional physical model can be used to simulate the migration process for small scale sand waves. Then, based on measured data, the evolution of the sand wave migration is investigated. An effective formula is developed to predict the migration rate, in which not only the effects of the environment but also the features of sand waves are considered.

关键词： small scale sand wave sand wave migration quasi-three-dimensional physical model numerical simulation in-situ measurement

Determination of organophosphorus pesticide residues in vegetables by an enzyme inhibition method using α-naphthyl acetate esterase extracted from wheat flour

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第4期13卷 267-273页

作者： Jun-liang WANG Qing XIA An-ping ZHANG Xiao-yan HU Chun-mian lin International Joint Research Center for Persistent Toxic Substances College of Biological and Environmental EngineeringZhejiang University of TechnologyHangzhou 310014China Zhejiang Province Environmental Radiation Monitoring Center Hangzhou 310012China

The widespread use of organophosphorus pesticides(OPs) poses a great threat to human health and has made the detection of OP residues in food an important task,especially in view of the fact that easy and rapid detection methods are *** OPs have inhibitory effects on the activity of α-naphthyl acetate esterase(ANAE) in plants,in this work we evaluated the possibility of detecting OPs in vegetables with ANAE extracted from commercial *** limits of detection(LODs) obtained for methamidophos,dichlorvos,phoxim,dimethoate,and malathion in lettuce samples with crude ANAE were 0.17,0.11,0.11,0.96,and 1.70 mg/kg,*** on the maximum residue limits(MRLs) for OPs in food stipulated by Chinese laws which are 0.05,0.20,0.05,1.00,and 8.00 mg/kg for methamidophos,dichlorvos,phoxim,dimethoate,and malathion,respectively,the esterase inhibition method with crude ANAE had sufficient sensitivity to detect the residues of dichlorvos,dimethoate,and malathion in lettuce,but it could not be used to guarantee the safety of the same samples if methamidophos or phoxim residue was *** sensitivity of the method was improved by the use of esterase purified by ammonium sulfate *** LODs obtained for methamidophos and phoxim with purified esterase were lower than the MRLs for these OPs in *** is a very promising method for the detection of OP residues in vegetables using crude or purified esterase because of its cheapness,sensitivity,and convenience.

关键词： Organophosphorus pesticides (OPs) α-Naphthyl acetate esterase (ANAE) Limit of detection (LOD) Enzvme inhibition Maximum residue levels (MRLs)

The effect of inhomogeneous water on seismic imaging in deepwater areas of the South China Sea

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Chinese Science Bulletin 2013年第30期58卷 4443-4449页

作者： JI LiLi lin mian HAO TianYao Institute of Geology and Geophysics Chinese Academy of Sciences Institute of Mechanics Chinese Academy of Sciences

This paper examines the effect of inhomogeneous water on seismic imaging in deep water *** appropriate partial differential equation is derived for the acoustic pressure field in inhomogeneous water,including current *** wavefields are simulated and the results show that the traveltime of seismic waves can be *** maximum traveltime perturbation at zero offset is 20 *** particular,the structure of horizontal reflectors below the water is distorted by mesoscale *** of water temperature are the fundamental cause of the ***,a calibration method for the distortion of seismic imaging caused by inhomogeneous water is presented.

关键词：地震成像深水区中国南海非均匀地震波场微分方程式传播时间校正方法

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Substitutions of the Conserved Gly47 Affect the CF1 Inhibitor and Proton Gate Functions of the Chloroplast ATP Synthase ε Subunit

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Acta Biochimica et Biophysica Sinica 2005年第7期37卷 453-462页

作者： Hui DONG Zhang-lin NI Jia-mian WEI Institute of Plant Physiology & Ecology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200032,China Institute of Plant Physiology & Ecology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200032 China

The conserved residue Gly47 of the chloroplast ATP synthase ε subunit was substituted withLeu,Arg,Ala and Glu by site-directed *** process generated the mutants εG47L,εG47R,εG47A and εG47E,*** the ε variants showed lower inhibitory effects on the soluble CF1（-ε）Ca2+-ATPase compared with wild-type ε.In reduced conditions,εG47E and εG47R had a lower inhibitoryeffect on the oxidized CF1（-ε）Ca2+-ATPase compared with wild-type ε.In contrast,εG47L and εG47Aincreased the Ca2+-ATPase activity of soluble oxidized CF1（-ε）.The replacement of Gly47 significantlyimpaired the interaction between the subunit ε and γ in an in vitro binding *** study showed thatall ε variants were more effective in blocking proton leakage from the thylakoid *** enhancedATP synthesis of the chloroplast and restored ATP synthesis activity of the reconstituted membranes to alevel that was more efficient than that achieved by wild-type ε.These results indicate that the conservedGly47 residue of the ε subunit is very important for maintaining the structure and function of the ε subunitand may affect the interaction between the ε subunit,β subunit of CF1and subunit Ⅲ of CF_o,therebyregulating the ATP hydrolysis and synthesis,as well as the proton translocation role of the subunit Ⅲ of CF_o.

关键词： chloroplast ATP synthase ε subunit GST pull-down assay site-directed mutagenesis

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振荡流作用下波状底床上流场特性的实验研究

地球物理学报 2005年第6期48卷 1466-1474页

作者：林缅袁志达中国科学院力学研究所北京100080

本文利用U型振荡水槽和粒子图像测速仪(PIV)对三种固定波状底床上的流场进行了测量,得到一系列不同振幅条件下的瞬时速度场和涡量场.通过分析不同时段涡强度以及涡轨迹,讨论了底床形状对其附近流场的影响.实验结果分析表明,底床形状决... 详细信息

本文利用U型振荡水槽和粒子图像测速仪(PIV)对三种固定波状底床上的流场进行了测量,得到一系列不同振幅条件下的瞬时速度场和涡量场.通过分析不同时段涡强度以及涡轨迹,讨论了底床形状对其附近流场的影响.实验结果分析表明,底床形状决定着整个涡量场特征及涡轨迹,从而决定着泥沙的净输移.这些结果对于探讨浅海区沙波、沙纹和沙垄等波状底床上泥沙输移的力学机制是很有意义的.

关键词：振荡流波状底床涡量涡轨迹