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Electron dynamics in collisionless magnetic reconnection with a PIC simulation

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Chinese science Bulletin 2009年第3期54卷 456-460页

作者： GUO Jun1,2.1 School of Mathematics and Physics, qingdao University of science and {2., qingdao 2.6042. China 2.State Key Laboratory of Space Weather, Chinese Academy of sciences, Beijing 100080, China School of Mathematics and Physics Qingdao University of Science and Technology Qingdao China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing China

Two-dimensional particle-in-cell (PIC) simulation is used to investigate electron dynamics in colli- sionless magnetic reconnection, and the proton/electron mass ratio is taken to be mi /me = 2.6. The results show that the presence of a strong initial guide field will change the direction of the electron flow. The electron density cavities and the parallel electric field can be found in the electron inflow re- gion along the separatrix, and the electron inflow and density cavities only appear in the second and fourth quadrants. What is different from the results with a smaller mass ratio is that new structures appear in the diffusion region near the X line: (1) Narrow regions of density enhancement and density cavities can be found synchronously in this region; and (2. corresponding to the electron density changes near the X line, the strong parallel electric fields are found to occur in the first and third quadrants. These electric fields perhaps play a more important role in acceleration and heating electrons than those fields located in the density cavities.

关键词： PIC模仿磁链接导向场电子动力学

Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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science China Chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2.& SHI TongShun2.1 College of Materials science and Engineering, shandong University of {2., Zibo 2.5049, China 2.Department of Chemistry, Jilin University, Changchun 13002., China 1. College of Materials science and Engineering Shandong University of Technology Zibo 255049 China 2. Department of Chemistry Jilin University Changchun 130023 China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12.kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

Research on Indicator System of Regional Eco-efficiency:A Case Study of Chengyang District

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Chinese Journal of Population,Resources and Environment 2006年第4期4卷 54-58页

作者： Zhou Zhenfeng1,2.Sun Lei2.Sun Yinglan2.1.College of Resources&Environment,Laiyang Agricultural College,qingdao,shandong 2.6109,China 2.School of Environmental {2. and Engineering,Ocean University of China,qingdao,shandong 2.6003,China College of Resources & Environment Laiyang Agricultural College Qingdao Shandong 266109 China School of Environmental science and Engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China

Eco-efficiency is a valuable tool for managing and solving issues involving resource consumption and pollution emission in current production *** the popularity of the term"eco-efficiency"in business,limited attention has been paid to measuring and reporting regional eco-efficiency for local government policy *** on the concept and method of eco-efficiency,an indicator system of regional eco-efficiency is established in this *** indicator system comprises 2. indicators,which are divided in to three categories including socio-economic development,resources consumption, environmental *** a promising statistical technique, principle component analysis is used to set the weight of indicators which attempts to calculate the eco-efficiency indices of qingdao's Chengyang *** results show that the eco-efficiency of Chengyang District has clearly improved 35.1% with small fluctuation from 1995 to ***-economic development index and resources consumption index also represent obvious increasing *** correlation coefficient between soci-economic development index and resources consumption index is 0.979,which means the social progress and economic growth of Chengyang District depend on an extravagant consumption of *** environmental pressure index increased slowly before 1997 and declined gradually after 1997,due to more attention being paid to environmental protection by local government in recent *** District still keeps the traditional economic development mode with a high consumption and high production,so the emphases of future development should put on improving the improving the efficient use of natural resources and promoting environmental management *** results show that the indicators system of regional eco-efficiency is a promising method to quantitatively evaluate resources and environmental efficiency and provide an effective decision-making support for local governments.

关键词： regional eco-efficiency indicator system Ecoefficiency Synthetic Index (ESI) Principle Component Analysis (PCA)

Israeli Water Achievements Today and Enlightenment to China

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Chinese Journal of Population,Resources and Environment 2008年第4期6卷 72-77页

作者： Sun Lei1,2. Xu Lanqing3 1. Institute of Environmental science and Engineering, Ocean University of China, qingdao {2. 2.6100, China 2. Department of Soil and Water sciences, Faculty of Agricultural, Food and Environmental Quality sciences, the Hebrew University of Jerusalem, 76100, Israel 3. Logistics Group of Ocean University of China, qingdao {2. 2.6100, China Institute of Environmental science and Engineering Ocean University of China Qingdao Shandong 266100 China Department of Soil and Water sciences Faculty of Agricultural Food and Environmental Quality Sciences the Hebrew University of Jerusalem 76100 Israel Logistics Group of Ocean University of China Qingdao Shandong 266100 China

Despite the endemic drought, arid climate and associated limited freshwater resources, as well as difficult geopolitical realities, Israel can provide a reliable supply of high quality water to a rapidly growing population. The achievements of water supply in Israel can be summarized as water technologies (like water transportation and purification, desalination, wastewater treatment, effluent reuse, storm water catchment, control systems, rain enhancement and drip irrigation, etc.), water management and legislation as well as water industry. In view of the national concern regarding the quality and quantity of the water, the skills, technologies and know-how that Israel has accumulated in water supply and irrigation can give us enlightenment that is also presented in this paper.

关键词： Israel China water technology water management water industry

Annealing effect on InP vertical porous arrays

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science China(Technological sciences) 2010年第6期53卷 1562-1566页

作者： SU Ge1,LIU TianZhong2.LIU Wei1 & CAO LiXin1 1 Institute of Material science and Engineering,Ocean University of China,qingdao 2.6100,China 2.qingdao Institute of BioEnergy and Bioprocess technology,Chinese Academy of sciences,qingdao 2.6101,China 1. Institute of Material science and Engineering Ocean University of China Qingdao 266100 China2. Qingdao Institute of BioEnergy and Bioprocess Technology Chinese Academy of Sciences Qingdao 266101 China

InP vertical porous arrays were produced using electrochemical etching at room *** as-etched InP samples were annealed in an ultra high vacuum ***-sectional analysis of the porous layer was conducted using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX).Annealing in vacuum was found to meliorate the structural quality of the porous *** results showed the composition change of the porous *** controlling the annealing process parameters,the content ratio of phosphorus (P) to indium (In) is *** property of the samples was also investigated at room *** with the sample without annealing treatment,Raman spectrum from the annealed sample showed red-shifted LO and TO peaks together with sharpened LO peak and shortened TO peak.

关键词： InP vertical porous arrays annealing effect Raman property electrochemical etching

Microstructure and Element Composition of Shell Plates of Liolophura japonica

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Wuhan University Journal of Natural sciences 2010年第2期15卷 176-184页

作者： CHEN Daohai1,2.1. College of Fisheries, Ocean University of China, qingdao 2.6003, Shangdong, China 2. Life science and {2. School, Zhanjiang Normal University, Zhanjiang 52.048, Guangdong, China College of Fisheries Ocean University of China Qingdao China Life science and technology School Zhanjiang Normal University Zhanjiang China

The microstructure characteristics of shell plates of chiton Liolophura japonica Lischke were analyzed using environmental scanning electron microscopy （ESEM）. The results show that the internal structure of the shell plate of chiton Liolophurajaponica is composed of seven calcium layers which were crossed lamellar crystallites, homoge- neous structure, granular crystallites, and trabecular type crystallites. The element compositions of shell plates were analyzed using X-ray photoelectron spectroscopy （XPS）. The results determined by XPS show that the surface chemical states of various layers are different. There are 13 elements （Na, O, N, C, S, P, Ca, C1, Si, A1, K, Fe, Mg） on the shell plate of chiton L. japonica. Among the 13 elements, 11 are on the outside pigment layer except K and S. Among seven layers of shell plate, there is the largest quantity of elements on the outside pigment layer, and the least quantity of elements is on layer C （Articulamentum auctorum）. There are 7 elements on the layer C （Articulamentum auctorum）. Be- sides calcium carbonate, there are some inorganic compounds on the shell plate, such as NaC1, MgO, A12.3, silicate, sulfate and phosphate. There are some organic chemical components, such as carbohydrate, organic sulfide, and organic nitride on the shell plates.

关键词： Liolophura japonica environmental scanning electron microscope X-ray photoelectron spectroscopy (XPS) microstructure of shell plate

Cubic surface fitting to image by combination

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science China(Information sciences) 2010年第7期53卷 1287-1295页

作者： LI XueMei1, ZHANG CaiMing1,2. YUE YiZhen1 & WANG KunPeng1 1School of Computer science and technology, {2. University, Jinan 2.0101, China 2.chool of Computer science and technology, {2. Economics University, Jinan 2.0014, China 1. School of Computer science and technology Shandong University Jinan 250101 China2. School of Computer Science and Technology Shandong Economics University Jinan 250014 China

We present a new method for constructing a fitting surface to image data. The new method is based on a supposition that the given image data are sampled from an original scene that can be represented by a surface defined by piecewise quadratic polynomials. The surface representing the original scene is known as the original surface in this paper. Unlike existing methods, which generally construct the fitting surface to the original surface using image data as interpolation data, the new method constructs the fitting surface using the image data as constraints to reverse the sampling process, which improves the approximation precision of the fitting surface. Associated with each data point and its near region, the new method constructs a quadratic polynomial patch locally using the sampling formula as constraint. The quadratic patch approximates the original surface with a quadratic polynomial precision. The fitting surface which approximates the original surface is formed by the combination of all the quadratic polynomial patches. The experiments demonstrate that compared with Bi-cubic and Separable PCC methods, the new method produced resized images with high precision and good quality.

关键词： surface fitting quadratic polynomial image resizing reversing

TWO CLASSES OF INTEGRABLE COUPLING FOR AKNS HIERARCHY

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Annals of Differential Equations 2009年第4期25卷 495-501页

作者： Wencai Zhao (College of science, shandong University of science and technology, qingdao 2.6510, shandong) Ling Li (College of Information science and Engineering, shandong University of science and technology, qingdao 2.6510, shandong)

A set of new matrix Lie algebra is constructed, which is devoted to obtaining a new loop algebra A 2. . Then we use the idea of enlarging spectral problems to make an enlarged spectral problems. It follows that the multi-component AKNS hierarchy is presented. Further, two classes of integrable coupling of the AKNS hierarchy are obtained by enlarging spectral problems.

关键词： integrable coupling AKNS hierarchy matrix loop algebra

A video encryption method based on chaotic maps in DCT domain

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Progress in Natural science:Materials International 2008年第10期18卷 1299-1304页

作者： Shuguo Yang~(a,b,*) Shenghe Sun~a ~a School of Electrical Engineering and Automation,Harbin Institute of technology,Harbin 150001,China ~b qingdao University of {2. and technology,qingdao 2.6061,China School of Electrical Engineering and Automation Harbin Institute of Technology Harbin 150001 China qingdao University of science and {2. Qingdao 266061 China

This paper proposes a new and secure video encryption method based on chaotic maps in DCT domain,which is quite in keeping with the common ideas and the frequent practices of video *** select the I-frames of the video sequence as encryption objects. First,we introduce two coupling chaotic maps to scramble the DCT coefficients of every original I-frame,and receive the scrambled ***,we encrypt the DCT coefficients of the scrambled 1-frame using another chaotic *** the whole process,we use three chaotic maps and five keys;the I-frame is encrypted ***,we performed several tests and the experimental results have proved our method to be secure and efficient.

关键词： Video encryption Chaotic map I-frame Scrambling Video sequence