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A NEW TREATMENT FOR INTERFACE OF METAL AND DIELECTRIC IN FDTD METHOD

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Acta Metallurgica Sinica(English Letters) 2001年第1期14卷 42-46页

作者： Z.D. Qian, B. W. Li, E.G. Wang, G.L. Jia and J.C. He (key laboratory of national Education Ministry for electromagnetic Processing of Materials, Northeastern University, Shenyang 110006, china) Northeastern Univ. Shenyang 110006 China

A new treatment for interface of metal and dielectric in finite-difference time domain (FDTD) method was presented, further how and why this treatment should be as it is was explained. The FDTD method was developed to compute the low-frequency electromagnetic fields in the metal instead of the traditional high-frequency ones as it was originally proposed. The computational results agreed well with the experimental ones.

关键词： method treatment for interface electromagnetic field numerical simulation

The equilibrium between diagenetic calcites and dolomites and its impact on reservoir quality in the sandstone reservoir of Kela 2 gas field

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Progress in Natural Science:Materials International 2007年第9期17卷 1051-1058页

作者： Gao Zhiqian1,Yu Bingsong2,3 and Lai Xingyun2,3(1.School of Energy Resources,china University of Geosciences,Beijing 100083,china 2.State key laboratory of Geological Processes and Mineral Resources,china University of Geosciences,Beijing 100083,china 3.Ministry of Education key laboratory of Lithosphere Structure,Deep Processes and Exploration Technique,china University of Geosciences,Beijing 100083,china) School of Energy Resources China University of Geosciences Beijing 100083 China State key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Ministry of Education key laboratory of Lithosphere Structure Deep Processes and Exploration Technique China University of Geosciences Beijing 100083 China

Based on the equilibrium theory of chemical reactions between water and rocks,this paper establishes a thermodynamic phase relationship diagram among calcites,dolomites and water solution under the condition of diagenesis based on the thermodynamic database of related minerals and fluids and dolomite's degree of order *** has been discovered that the equilibrium between calcites and dolomites in the diagenetic environment is strongly impacted by temperature and the Ca/Mg ratios in groundwater,and that the dolomite's degree of order in the diagenetic environment is a function of crystallization temperature and time,not controlled by water ***,the authors make a further analysis of the close relationship of chemical reaction between carbonate cements and pore water in the sandstone reservoirs of Kala 2 gas field in Kuche *** can be seen that there are different impacts on sandstone reservoir quality among the equilibrium system of calcites,dolomites and pore water at different depths of reservoirs.

关键词： diagenesis equilibrium between calcites and dolomites secondary pores Kela 2 gas field

High-g Impact Resistance for Epoxy Molding Compound

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Journal of Wuhan University of Technology(Materials Science) 2010年第4期25卷 588-591页

作者：靳鸿 national key laboratory of Science and Technology on Electronic Test and Measurement North University of China key laboratory of Instrumentation Science & Dynamic Measurement North University of China Ministry of Education

The behavior of resistance high-g impact of EMC （epoxy molding compound） with two package models, small outline package （POS） and Globtop, was evaluated by experimental method used Hopkinson bar. At 120,000 g （generated in the Hopkinson bar with widths about 70 μs） no damage in either the POS devices or the Globtop devices was observed. In order to enhance the EMC＇s ability of resistance high-g impact, buffering effect of epoxy resin was also studied. The experimental results above all show that EMC has a better performance of impact resistance at about 120,000 g, and epoxy resin can absorb the stress wave to have the protected ability. The study of this paper could serve as a basis for selection packaging materials and enhance its reliability in high-g impact environment.

关键词： epoxy molding compound (EMC) reliability high-g impact hopkinson bar

SINGULAR BEHAVIORS OF INTERFACIAL CRACKS IN 2D MAGNETOELECTROELASTIC BIMATERIALS

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Acta Mechanica Solida Sinica 2009年第3期22卷 232-239页

作者： Cuiying Fan1 Youhe Zhou1 Han Wang2 Minghao Zhao1,2(1key laboratory of Mechanics on Disaster and environment in Western china,the Ministry of Education of china,and Department of Mechanics and Engineering Science,College of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,china)(2School of Mechanical Engineering,Zhengzhou University,Zhengzhou 450001,china) [a]key laboratory of Mechanics on Disaster and environment in Western china the Ministry of Education of China and Department of Mechanics and Engineering Science College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China [b]School of Mechanical Engineering Zhengzhou University Zhengzhou 450001 China

The singular characteristics of stress,electric displacement and magnetic induction fields near the tip of impermeable interfacial cracks in two-dimensional magnetoelectroelastic bimaterials are studied using the generalized Stroh *** types of singularities are ob-tained:one is the oscillating singularity 1/2±iε,the other is the non-oscillating singularity 1/2±κ.It is found that the non-zero parameters ε and κ cannot coexist for one transversely isotropic MEE bimaterial,a similar result is obtained for transversely isotropic piezoelectric bimaterials.

关键词： generalized Stroh formalism magnetoelectroelastic bimaterial interfacial crack singularity index

The Optimal Cross-section Design of the “Trapezoid-V” Shaped Drainage Canal of Viscous Debris Flow

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Journal of Mountain Science 2011年第1期8卷 103-107页

作者： YOU Yong key laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu 610041 China

Debris flow drainage canal is one of the most widely used engineering measures to prevent and manage debris flow *** shape and the sizes of the cross-section are important parameters when design debris flow drainage ***,how to design the appropriate shape and sizes of the cross-section so that the drainage canal can have the optimal drainage capacity is very important and few researched at home and *** study was conducted to analyze the hydraulic condition of a Trapezoid-V shaped drainage canal and optimize its *** assuming characteristic sizes of the cross-section,the paper deduced the configuration parameter of the cross-section of a Trapezoid-V shaped debris flow drainage *** theory analysis,it indicates that the optimal configuration parameter is only related to the side slope coefficient and the bottom transverse slope *** this study,the Heishui Gully,a first-order tributary of the lower Jinsha River,was used as an example to design the optimal cross-section of the drainage canal of debris flow.

关键词： Optimal cross-section design Trapezoid- V shaped Drainage canal Viscous debris flow

Water-vapor source shift of Xinjiang region during the recent twenty years

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Progress in Natural Science:Materials International 2007年第5期17卷 569-575页

作者： Dai Xingang , Li Weijing , Ma Zhuguo and Wang Ping (key laboratory of Regional Climate-environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china laboratory for Climate Change, Chinese Meteorological Administration, Beijing 100081, china) [a]key laboratory of Regional Climate-environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences Beijing China [b]laboratory for Climate Change Chinese Meteorological Administration Beijing China

The aim of this paper is to investigate the climate water-vapor sources of Xinjiang region and their shifts during the past 20 years. First, the principle and steps are roughly regulated to seek the water-vapor sources. Second, the climate stationary water-vapor transport in troposphere is calculated to distinguish where the water vapor comes from by ERA-40 reanalysis. In addition, the collocation between the transport and the atmospheric column water vapor content is analyzed. The results show that the major vapor comes from the west side of Xinjiang for mid-month of seasons, apart from July while the water vapor comes from the north or northwest direction. The water vapor sources are different for different seasons, for example, the Caspian Sea and Mediterranean are the sources in January and April, the North Atlantic and the Arctic sea in July, and the Black Sea and Caspian Sea in October, respectively. In recent ten years more water vapor above Xinjiang comes from the high latitudes and the Arctic sea with global warming, and less from Mediterranean in comparison with the case of 1973—1986. In fact, the air over subtropics becomes dry and the anomalous water vapor transport direction turns to west or southwest during 1987—2000. By contrast, the air over middle and high latitudes is warmer and wetter than 14 years ago.

关键词： global warming water-vapor source water-vapor transport precipitable water Xinjiang climate inter-decadal change.

Spectral response of rice(Oryza sativa L.) leaves to Fe^(2+) stress

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Science china(Life Sciences) 2009年第8期52卷 747-753页

作者： CHI GuangYu1,2,CHEN Xin1,SHI Yi1 & LIU XinHui3 1 key laboratory of Terrestrial Ecological Process,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,china 2 Graduate School of Chinese Academy of Sciences,Beijing 100049,china 3 State key Joint laboratory of environmental Simulation and Pollution Control,School of environment,Beijing Normal University,Beijing 100875,china key laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100049 China State key Joint laboratory of environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

In the management of lake eutrophication,the regulation effect of Fe is considered,in addition to the controlling nitrogen-and phosphorus *** on the "Fe hypothesis",this paper tentatively applied plant spectral response to the remote sensing early-warning mechanism of lake eutrophication.A laboratory water culture experiment with rice(Oryza sativa L.) was conducted to study Fe uptake by plants and the chlorophyll concentration and visible-near infrared spectrum of vegetable leaves as well as their interrelations under Fe2+ *** spectral indices,i.e.,A1(integral value of the changes of spectral reflectivity in the range 460―670 nm under Fe2+ stress),A2(integral value of the changes of spectral reflectivity in the range of 760―1000 nm under Fe2+ stress) and S(blue-shift range of red edge curve under Fe2+ stress),were used to establish quantitative models about the relationships between the rice leaf spectrum and Fe2+ *** the increase of Fe2+ in a culture solution,the Fe content in rice plants increased,while the chlorophyll concentration in vegetative leaves *** spectral reflectivity of vegetable leaves increased in the visible light band but decreased in the near infrared band,and the blue-shift range of the red edge curve *** indices A1,A2 and S all had significant correlations with the Fe content in rice leaves,the correlation coefficient being respectively 0.951(P 2 > 0.96) and predict the Fe level in rice leaves.

关键词： rice(Oryza sativa L.) spectrum Fe2+ lake eutrophication

A theoretical model of collision between soft-spheres with Hertz elastic loading and nonlinear plastic unloading

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Theoretical & Applied Mechanics Letters 2011年第4期1卷 34-39页

作者： Youhe Zhou 1,2,a) 1) key laboratory of Mechanics on Disaster and environment in Western china,the Ministry of Education of china 2)Department of Mechanics and Engineering Science,College of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,china Department of Mechanics and Engineering Science College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China

This paper presents a theoretical model on the normal(head-on) collision between soft-spheres on the basis of elastic loading of the Hertz contact for compression process and a nonlinear plastic unloading for restitution one,in which the parameters all are determined in terms of the material and geometric ones of the spheres,and the behaviors of perfect elastic,inelastic,and perfect plastic collisions appeared in the classical mechanics are fully described once a value of coefficient of restitution is specified in the region of 0 ≤ ε ≤ *** an empirical formula of the coefficient of restitution dependent on the impact velocity is suggested to fit the existing experimental measurements by means of the least square method,the predictions of the dependency and the collision duration are in well quantitative agreement with their experimental *** is found that the measurable quantities are dependent on both the impact velocity and the parameters of *** this model,finally,an approach to determine the spring coefficient in the linear viscoelastic model of the collision is also *** results obtained here will be significantly beneficial for the applications where a collision model is requested in the simulations of relevant grain flows and impact dynamics etc..

关键词： normal collision of soft-spheres theoretical model residual displacement restitution coefficient collision duration

Sequential Extraction of Natural Surface Coatings: Comparison with Single Stage Extraction and Its Application in Investigating Adsorption Characteristics of Surface Coating Components for Metals

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Chemical Research in Chinese Universities 2012年第1期28卷 41-46页

作者： HUA Xiu-yi, LIU Xiao-xue, DONG De-ming, LI Ming and LI Yao-rui key laboratory of Groundwater Resources and environment, Ministry of Education, key Lab of Water Resources and Aquatic environment of Jilin Province, College of environment and Resources, Jilin University, Changchun 130012, P. R. china Jilin Univ Key Lab Groundwater Resources & Environm Key Lab Water Resources & Aquat Environm Jilin Pr Minist EducColl Environm & Resources Changchun 130012 Peoples R China

Multistage sequential extraction with different sequences was applied to extracting natural surface coa tings（NSCs）, and the results were compared with those by single stage extraction technique. The optimal sequential extraction scheme with the best performance was selected and incorporated into the method of selective extraction followed by adsorption and statistic analyses to study the adsorption parameters of Fe oxides, Mn oxides and organic matters in NSCs for Pb and Cd, to validate the applicability of the sequential extraction scheme. The Langmuir ad sorption parameters of each component of surface coating estimated according to the adsorption data of single stage extraction of NSCs were all similar to those of sequential extraction of NSCs, and the maximum difference between the metal adsorption abilities of the components estimated via the two extraction techniques was only about 20%, in dicating that either extraction techniques could be used. The optimal sequential extraction scheme obtained was first extracted with NH2OH·HCl, then with Na2S2O4, and finally with oxalic acid.

关键词： Natural surface coating(NSC) Sequential extraction Single stage extraction Adsorption Component