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An ecological hydraulic radius approach to estimate the instream ecological water requirement

Progress in Natural Science:Materials International 2007年第3期17卷 320-327页

作者： LIU Changming and MEN Baohui ( Key Laboratory of Water Cycle and Related Land Surface Process, Institute of Geographical Sciences and Natural resources Research, Chinese Academy of Sciences, beijing 100101, china Key Laboratory of Water and Sediment Sciences, Ministry of Education & Water Sciences {3., beijing normal university, beijing 100875, china Department of Hydraulic and Hydropower Engineering, North china Electric Power university, beijing 102206, china) [a]Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China [b]Key Laboratory of Water and Sediment Sciences Ministry of Education & Water Sciences Gllege Beijing Noirnal University Beijing China [c]Departhent of Hydraulic and Hydropower Engineering North China Elecfric Power University Beijing China

This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc.). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.

关键词： ecological flow flow velocity cross-sectional flow area ecological hydraulic radius (HER) instreamecological water requirement.

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Analysis of china’s Water Security and Virtual Water Trade

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Chinese Journal of Population,resources and Environment 2006年第4期4卷 18-23页

作者： Wang Hongrui1,2,Liu Xinghan3.Dong Yanyan1,2,Wang Junhong1,2 1.college of Water Sciences,beijing normal {3.,beijing 100875,china 2.Key Laboratory for Water and Sediment Sciences Ministry of Education,beijing 100875,china 3.college of Economics&Management,beijing {3. of {13.,beijing 100022,china college of Water Sciences Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Sciences Ministry of Education Beijing 100875 China college of Economics & Management Beijing University of Technology Beijing 100022 China College of Water Sciences Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Sciences Ministry of Education Beijing 100875 China college of Water Sciences Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Sciences Ministry of Education Beijing 100875 China

Producing goods and services all needs water *** water used in the process of an agricultural or industrial product is called the"Virtual Water"contained in this product. Through international trade,water-scarce countries and regions could purchase water-intensive products--especially foods,from water-rich countries to balance their water deficits and achieve water *** is one of the 13.most water-deficit countries whose water safety have been severely *** paper generalized the recent global research development and made a brief introduction about the methods calculating virtual water content in specific *** a case study,we qualified china's annual virtual water flows from year 2000 to 2002 with trade in crops,and ended with some policy advice for application and practice of virtual water strategy.

关键词： water security virtual water virtual water trade crops

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Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2, LIU Chang-hua2, ZHANG He-bing2 1. college of resources Science and technology,{3., beijing 100875, china 2. School of Surveying and Land Information Engineering, Henan Polytechnic university, Jiaozuo 454000, china [a] college of resources Science and technology Beijing Normal University Beijing 100875 China [b] School of Surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

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Geographical Agglomeration of Chinese Manufacturing Industries

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中国人口·资源与环境：英文版 2007年第2期5卷 3-11页

作者： Zhang Hua 1, 2, Zheng Wei3.1. Institute of Geographical Sciences and Natural resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Graduate School of the Chinese Academy of Sciences, beijing 10003., china 3. School of Geography, beijing normal university, beijing 100875, china Institute of Geographical Sciences and Natural resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China School of Geography Beijing Normal University Beijing 100875 China

Based on the plant level data from the First National Census of Basic Units, the Second National Census of Basic Units, and the First National Economic Census of china, this paper ex- amines the geographical agglomeration of Chinese manufacturing industries at a more disaggregated level both by industrial classi-fication and spatial unit analysis. Applying the agglomeration index proposed by Maurel and Sedillot, studies show that the most agglomerated industries are resource-intensive, and capital and technology intensive while industries demanding localized inputs or serving localized markets or favored by local governments are fairly dispersed. The more disaggregated industries are more spa- tially agglomerated. At the finer spatial scale, industries are more dispersed. Results indicate that within-county spillovers are stronger than nearby-county spillovers, and within-prefecture spillovers are stronger than nearby prefecture spillovers. Local- ized spillovers are still quite substantial at a range beyond that of counties. Comparing the agglomeration index of Chinese manu- facturing industries in 1996, 2001 and 2004, agglomeration seems to be a general tendency. Results also indicate that some industries have experienced remarkable changes in their levels of agglom- eration in the period 1996–2004.

关键词： industrial agglomeration manufacturing industries the MS index

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Influence of Zn ion implantation on structures and field emission properties of multi-walled carbon nanotube arrays

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Science china(Technological Sciences) 2010年第3期53卷 776-781页

作者： CHEN KeFan,DENG JianHua,ZHAO Fei,CHENG GuoAn &ZHENG RuiTing Key Laboratory of Beam technology and Material Modification of Ministry of Education,college of Nuclear Science and technology,{3. normal university,{3.100875,china 1. Key Laboratory of Beam technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing 100875 China

The structures and field emission properties of multi-walled carbon nanotube arrays implanted with Zn+ by MEVVA ion implanter have been *** results revealed that Zn+implantation induced structural damage and that the top of carbon nanotubes with multi-layered graphite structure were transformed into carbon nanowires with amorphous ***,C:Zn solid solution was synthesized after Zn+ *** turn-on field and threshold field were 0.80 and 1.3. V/μm,respectively for original multi-walled carbon nanotube arrays and were reduced to 0.66 and 1.04 V/μm due to the synthesis of C and Zn composite,in which the work function was reduced after low doses of Zn+*** is indicated that low doses of Zn+implantation can improve field emission performance of multi-walled carbon nanotube ***,high doses of Zn+implantation can reduce field emission properties of multi-walled carbon nanotube arrays,because radiation damage reduces the electric field enhancement factor.

关键词： multi-walled carbon nanotubes ion implantation field electron emission

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Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

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Science china Earth Sciences 2010年第5期53卷 721-730页

作者： WANG DongWei1,2,3. WANG JinDi1,2 & LIANG ShunLin4 1 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by beijing normal university and Institute of Remote Sensing Applications, CAS, beijing 100875, china 2 School of Geography, {3. Key Laboratory of Environmental Remote Sensing and Digital City, beijing normal university, beijing 100875, china 3.Haihe River Water Conservancy Commission, Tianjin 3.0170, china 4 Department of Geography, university of Maryland, college Park, MD 20742, USA 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing 100875 China2. School of Geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing 100875 China3. Haihe River Water Conservancy Commission Tianjin 300170 China4. Department of Geography University of Maryland College Park MD 20742 USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The key approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of beijing, this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS

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Using remote sensing to research beijing wetlands dynamics

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Science china(Technological Sciences) 2006年第z2期49卷 97-107页

作者： ZHAO Wenji, GONG Zhaoning, GONG Huili, LI Xiaojuan, ZHANG Songmei & LI Jing Key Lab of Resource Environment and GIS of beijing, Capital normal university, beijing 10003., china Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 13.012, china college of resources Science and technology, beijing normal university, beijing 100875, china Capital normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital normal Univ GIS Beijing Beijing 100037 Peoples R China Chinese Acad Sci NE Inst Geog & Agroecol Changchun 130012 Peoples R China beijing normal Univ Coll Resources Sci & Technol Beijing 100875 Peoples R China

In beijing, where wetlands are important to municipal freshwater conservation and biodiversity retention, three different types of wetlands were identified: riverside wetlands, wetlands surrounding lakes and reservoirs, and wetlands in municipal *** sensing technology was applied in combination with field investigations to monitor and analyze the changes in these wetlands, and a combination of fusion technologies,Landsat TM/ETM+ and IKONOS imaging, was used to investigate and map them. This study indicates that not only have wetland areas been reduced by half, but also their ecological environments have been degraded because of rapid economic development and population increase. Suggestions based on this research are made to reconstruct the ecological environment of the wetlands and return them to their previous state.

关键词： beijing, wetland resource, remote sensing technology, ecological environment, dynamics.

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Level Set interface treatment and its application in Euler method

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 227-236页

作者： WU KaiTeng1,2,HAO Li3.WANG Cheng4 & ZHANG Li1,2 1 Numerical Simulation Sichuan Higher School Key Laboratory,Neijiang normal university,Neijiang 641112,china 2 {3. of Mathematics and Information Science,Neijiang normal university,Neijiang 641112,china 3.{3. of Science,beijing university of Civil Engineering and Architecture,beijing 100044,china 4 State Key Laboratory of Explosion Science and technology,beijing Institute of technology,beijing 100081,china 1. Numerical Simulation Sichuan Higher School Key Laboratory Neijiang Normal University Neijiang 641112 China2. College of Mathematics and Information Science Neijiang Normal University Neijiang 641112 China3. College of Science Beijing University of Civil Engineering and Architecture Beijing 100044 China4. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China

Level Set interface treatment method is introduced into Euler method,which is employed for interface treatment method for multi-materials. Combined with the ghost fluid method,the moving interface is tracked. Fifth-order WENO spatial discretization and third-order TVD Runge-Kutta time discretization methods are used. Shock-wave action on bubble,implosion and velocity field Shock effect bubbles; implosion and velocity field are simulated by means of LS-MMIC3. programmed by C++. Nu-merical results show that the Level Set interface treatment method is effective and feasible for multi-material interface treatment in comparison with the WENO method.

关键词： Euler method Level Set method shock-wave action on bubble implosion numerical simulation

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The Villin/Gelsolin/Fragmin Superfamily Proteins in Plants

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Journal of Integrative Plant Biology 2007年第8期49卷 1183-1191页

作者： Hui Su Ting Wang Huaijian Dong Haiyun Ren (Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and college of Life Sciences beijing normal {3. beijing 100875 china Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Sciences Beijing Normal University Beijing 100875 China

The villin/gelsolin/fragmin superfamily is a conserved Ca^2＋-dependent family of actin-regulating proteins that is widely present both in mammalian and non-mammalian organisms. They have traditionally been characterized by the same core of three or six tandem gelsolin subdomains. The study in vertebrates and lower eukaryotic cells has revealed that the villin/gelsolin/fragmin superfamily of proteins has versatile functions including severing, capping, nucleating or bundling actin filaments. In plants, encouraging progress has been made in this field of research in recent years. This review will summarize the identified plant homologs of villin/gelsolin/fragmin superfamily, thus providing a basis for reflection on their biochemical activities and functions in plants.

关键词： actin-binding protein actin cytoskeleton Villin/Gelsolin/Fragmin.

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The ε-Complexity of the Approximate Solution of Integral Equations with Isotropic Kernels

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Acta Mathematica Sinica,English Series 2002年第4期18卷 679-686页

作者： Wan MA Gen Sun FANG college of Mathematics & Information Science of Wenzhou university, Wenzhou 3.5027, P. R. china Department of Mathematics,{3., beijing 100875, P. R. china college of Mathematics & Information Science of Wenzhou university Wenzhou 325027 P. R. China Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

The exact order of s-complexity is determined in L_p (2≤p≤∞) spaces for the second kind of Fredholm integral equations with kernels belonging to an isotropic Sobolev class.

关键词： Fredholm equation ε-complexity Sobolev classes

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