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Temporal variation of suspended sediment load in the Pearl River due to human activities

International Journal of Sediment Research 2011年第4期26卷 487-497页

作者： Wei ZHANG,Shousheng MU,Yanjing ZHANG,and Kaimin CHEN 1 Assoc.Prof.,State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering,Hohai University, Nanjing,210098,China, 2,4.Graduate student,College of Harbor,Coastal and Offshore engineering,Hohai University,Nanjing,210098, China 3 Prof.,China Institute of Water Resources and Hydropower Research,beijing,100038,China [a] Assoc. Prof. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China [b] Graduate student College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China [c] Prof. China Institute of Water Resources and Hydropower Research Beijing 100038 China [d] Graduate student College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

Data on sediment flux at three hydrologic stations from the 1950s to 2006 are utilized to study the decadal,annual,and monthly variations in suspended sediment load delivered from the Pearl River to the *** show that variations in sediment flux from three main tributaries,including the West River,the North River and the East River,are spatially *** nearly 90%of the suspended sediment load comes from the West River,its variation has dominated the overall tendency of sediment flux in the entire Pearl *** a significant decreasing trend exists in the annual variation of the total sediment flux,the decadal change can be divided into an increasing phase and a decreasing phase,with the turning point between the two phases in the late *** the 1950s to the 1980s,the average annual river sediment flux increased by 30.4.%.However,sediment flux has decreased significantly since the 1990s,with the average sediment flux being 38.60%less in the 2000s than that in the *** current sediment flux is also 52.93%less than its peak in the 1980s. The monthly variation pattern of the suspended sediment load transport to the sea is more interesting. For the West River,all months show a decreasing trend,and for most months the reduction values are ***,for the East River the sediment load shows a decrease trend in the dry season and an increase trend in the wet *** method of regression analysis was used to study the influence of precipitation in the variation on the sediment *** was found that the climate change is not the main driving force behind the variation in suspended sediment *** the 1990s, intensive land use destroyed the vulnerable ecosystem of the upper Pearl River,and speeded up the process of rocky ***,aggravated soil erosion caused an increase in suspended sediment ***,sediment retention within reservoirs had begun to play a dominant role after the massive constru

关键词： Pearl River Sediment flux Human activities Rocky desertification Dam construction

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Slope Reinforcement for Housing in Three Gorges Reservoir Area

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Journal of Mountain Science 2011年第2期8卷 314-320页

作者： WU Faquan LUO Yuanhua CHANG Zhonghua Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Office of Three Gorges Project Construction Committee the State Council of China Beijing 100038 China

The Three Gorges Project of the Yangtze River is the largest hydropower-complex project under construction in the world. Under the largescale relocation projects, 2874.engineered slopes are formed along with the construction of new towns. In this paper, the cutting slopes are mainly soil slopes and rock slopes. Soil slopes include residual soil slopes, colluvial accumulation slopes, swelling soil slopes, and artificial earth fill slopes, etc. Rock slopes include blocky structure rock slopes, layer structure rock slopes, and clastic structure rock slopes, etc. Varied protection measures have been used for slope protection in the reservoir area including shotcrete concrete-anchor bars, frame beams, retaining walls, slope stabilizing piles, sheet-pile walls, anchorage anti-shear tunnels, flexible protection grids, and drainage, etc. Besides, slope deformation monitoring systems have been set up to monitor deformation failure and the stability state of slopes. The protection measures have guaranteed slope safety and maintained a harmony with the urban environment and surrounding landscape.

关键词： Slope reinforcement Housing for resettlement Three Gorges Reservoir

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Numerical study of M_2 internal tide generation and propagation in the Luzon Strait

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Acta Oceanologica Sinica 2011年第5期30卷 23-32页

作者： LI Huan SONG Dan CHEN Xueen QIAN Hongbao MU Lin SONG Jun National Marine Data and Information Service State Oceanic Administration Tianjin 300171 China Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China College of Physical and Environmental Oceanography Ocean University of China Qingdao 266100 China Administrative Center for China＇s Agenda 21 Beijing 100038 China

Based on the z-coordinate ocean model HAMSOM,we introduced the internal-tide viscosity term and applied the model to numerically investigate the M2 internal tide generation and propagation in the Luzon Strait （LS）.The results show that （1） in the upper 250 m depth,at the thermocline,the maximum amplitude of the generated internal tides in the LS can reach 4. m;（2） the major internal tides are generated to the northwest of Itbayat Island,the southwest of Batan Island and the northwest of the Babuyan Islands;（3） during the propagation the baroclinic energy scattering and reflection is obvious,which exists under the effect of the specific topography in the South China Sea （SCS）;（4. the westward-propagating internal tides are divided into two branches entering the *** passing through 118 E,the major branch is divided into two branches *** strongest internal tides in the LS are generated to the northwest of Itbayat Island and propagate northeastward to the ***,to the east of 122 E,most of the internal tides propagate southeastward to the Pacific as a beam.

关键词： M2 internal tides HAMSOM Internal tidal energy flux Luzon Strait

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An Interpretation of the Influential Power of China Development

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chinese Journal of Population,Resources and Environment 2012年第2期10卷 12-23页

作者： Zhou Hailin Guo Chaoxian The Administrative Center for China's Agenda 21 Beijing 100038 China Institute of Industrial Economics of chinese academy of Social Sciences Beijing 100836 China

Through the analysis on China＇s economic develop- ment, utilization of resource environment and soft power, a basic judgment was made of the influence of ＂China development＂. The overall influential power of China development on international community was misunderstood. What we see is the role of ＂China Factor＂ in different fields. In the process of economic globalization, what economic system of capitalist market has seen is ＂China＇s cheap labor＂, ＂China＇s loose economic system environment＂, ＂earlier abuse of unlimited resource environment＂, ＂China＇s broad consumption market＂ and ＂demographic dividend＂. In global or Asian financial crisis, what other countries valued was China＇s ＂foreign currency＂ accumulated over the years. In global gov- ernance or crisis management, what international community expected was ＂China＇s obligations and responsibilities＂ without the right of speech, etc.. All these are the ＂passive＂ roles produced by ＂a single factor＂ in definite fields. The active and initiative role China will play in international community still needs time and the continuous efforts of several generations. China once was a big country that had significant inftuential power on the world, and China＇s renaissance is a normal process of development of things. What excessive talks about its influential power reflect may be the lack of China＇s influence.

关键词： China development influential power China Factor interpretation

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An Automatic Approach to Extracting Review Link from chinese News Pages

An Automatic Approach to Extracting Review Link from Chinese...

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2011 6th IEEE Joint International Information Technology and Artificial Intelligence Conference(ITAIC 2011)

作者： Wei Liu Information Source Center Institute of Scientific and Technical Information of China beijing 100038

Review links are widely used in some special kinds of web pages,especially news *** are very useful pieces of information in many applications,such as hot topic discovery and public opinion ***,extracting review links manually from news pages is timeconsuming and *** lots of works on web data extraction have been developed,we argue that this is still not a trivial problem due to the diversity on both DOM tree structure and visual *** this paper,a novel approach is proposed for automatically extracting the review links from web *** approach consists of two steps:first segment each news page into a set of blocks,and then identify the block（s） that contain the review link using a machine learning *** results over a large number of chinese news pages indicate that this approach is highly accurate.

关键词： Web data extraction Review link Machine learning Visual feature

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Synthesis and Crystal Structure of H_2Mo_8O_(26)〔(n-Bu)_4._2〔(CH_3)_2 COHCH_2COCH_3〕_2

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chinese Journal of Structural Chemistry 2000年第3期19卷 163-167页

作者： LU Xiao Ming (Department of Chemistry, Capital Normal University, beijing, 100037) LI Wen Jun (Department of Science, chinese People’s Public Security University, beijing, 100038) MAO Xi An (Wuhan Institute of Physics and Mathematics, Th

The title compound 4. methyl 4. hydroxy 2 pentone is obtained by the condensed reaction of acetone, and co crystallized with octamolybdate anion and tetra butyl ammonium cation. The crystal structure belongs to triclinic system, space group P1 , Mo 8C 4. H 98 O 30 N 2 M r=1902.77, a=11.512(6), b=12.790(3), c=13.395(4., α=65.22(2), β=78.26(4., γ=71.12(3), V=1689(1) 3, Z=1, D x =1\^869g/cm 3, F(000)=950, μ =14.79 cm -1 , final R =0.053 and R w =0.067. The orbital hybridization of C(53) and C(55) are sp 3 and sp 2 separately in (CH 3) 2COHCH 2COCH 3 and the catalysis of β octamolybdate anion might be present for the condensed reaction of acetone.

关键词： acetone 4.methyl-4.hydroxy-2-pentone octamolybdate catalysis

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Strategies for managing reservoir sedimentation

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International Journal of Sediment Research 2009年第4期24卷 369-384页

作者： Zhao-yin WANG 1 and Chunhong HU 21 Prof., State Key Lab of Hydroscience and engineering, Tsinghua University, beijing 100084. China. 2 Prof., Secretary General of International Research and Training Center on Erosion and Sedimentation, beijing 10004., China and Vice President of China Institute of Water Resources and Hydropower Research, No. A-1, Fuxing Rd, beijing 100038, China. [a] Prof. State Key Lab of Hydroscience and engineering Tsinghua University beijing 100084 China [b] Prof. Secretary General of International Research and Training Center on Erosion and Sedimentation beijing 10004. China and Vice President of China Institute of Water Resources and Hydropower Research No. A-1 Fuxing Rd beijing 100038 China

Sediment deposition in reservoirs has caused the loss of 66% of the reservoir capacity in China. The main sedimentation control strategies are: 1) storing the clear water and releasing the turbid water; 2) releasing turbidity currents; 3) Draw-down flushing and empty flushing; and 4. dredging. The paper summarizes these strategies with examples. Sediment transport in many chinese rivers occurs mostly during the 2-4.month flood season, that is, 80-90% of the annual sediment load is transported with 50-60% of the annual runoff. By storing the clear water after the flood season and releasing the turbid water during the flood season, less sediment deposits in the reservoir while the reservoir is still able to store enough water for power generation in the low flow season. The Three Gorges and Sanmenxia reservoirs apply this strategy and control sedimentation effectively. Turbidity currents have become the main sedimentation control strategy for the Xiaolangdi Reservoir. Empty flushing involves reservoir draw-down to temporarily establish riverine flow along the impound reach, flushing the eroded sediment through the outlets. Case studies with the Hengshan Reservoir and Zhuwo Reservoir are presented. Jet dredgers have been used to agitate the reservoir deposit so that the deposit is released from the reservoir with currents. The sediment releasing efficiency is 30-100% for storing the clear and releasing the turbid; 6-4. % for turbidity current; and 2,4.0-5,500% for empty flushing. Empty flushing causes high ecological stress on the ecosystem to the downstream reaches. Storing the clear and releasing the turbid is the best strategy to control reservoir sedimentation while achieving hydro-power benefit and maintain ecological stability.

关键词： Reservoir sedimentation Storing clear and releasing turbid Flushing Turbidity current Three Gorges Reservoir

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THE RESEARCH ON THE REASON, PREVENTION AND TREATMENT OF SPORT INJURY OF WUSHU

THE RESEARCH ON THE REASON, PREVENTION AND TREATMENT OF SPOR...

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第4.全国青年体育科学学术会议

作者： He Jian,Shi Zhiyong Department of Police Sport Training of China People''s Public Security University, beijing 100038 Guang An Men Hospital The China academy of Traditional chinese Medicine, beijing 100053

＜正＞Objective: Wushu is a traditional sport game with a high injury rate. The aim of this thesis is to study the reasons, prevention and treatment of sport injury of Wushu, and then to offer references for the coaches. Method: 1. Research method: document information, clinical research, statistical analysis, expert visits. 2.

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配合物La(C_5O_3H_3)_3·C_(12)H_8N_2·H_2O的合成和表征

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光谱学与光谱分析 1999年第6期19卷 821-823页

作者：李夏邓玉恒李文君首都师范大学化学系北京100037 中国人民公安大学北京100038

本文以α－呋喃甲酸（Ｃ５Ｏ３Ｈ４）和邻菲罗啉（Ｃ１２Ｈ８Ｎ２）为配体，在乙醇溶剂中与硝酸镧反应，合成了与稀土离子Ｌａ（Ⅲ）的三元混配配合物。经元素分析确定其配合物的组成为Ｌａ（Ｃ５Ｏ３Ｈ３）３ ·Ｃ１２Ｈ８Ｎ２·Ｈ... 详细信息

本文以α－呋喃甲酸（Ｃ５Ｏ３Ｈ４）和邻菲罗啉（Ｃ１２Ｈ８Ｎ２）为配体，在乙醇溶剂中与硝酸镧反应，合成了与稀土离子Ｌａ（Ⅲ）的三元混配配合物。经元素分析确定其配合物的组成为Ｌａ（Ｃ５Ｏ３Ｈ３）３ ·Ｃ１２Ｈ８Ｎ２·Ｈ２Ｏ，同时还通过ＩＲ、１ＨＮＭＲ、ＵＶ、ＴＧ－ＤＴＡ等谱学的测试与分析，表征了配合物的组成结构和性质。ＩＲ、１ＨＮＭＲ和ＵＶ谱的分析结果表明配体羧酸是以脱质子的酸根形式与中心稀土离子Ｌａ（Ⅲ）配位的，而邻菲罗啉配体上的Ｎ原子则采用了双齿螯合配位形式。ＴＧ－ＤＴＡ的数据分析表明，化合物在常温下是稳定的。随着温度的上升，配合物先后经历了一个脱水、有机配体的氧化分解、直至生成稳定的Ｌａ２Ｏ３的过程。

关键词：镧呋喃甲酸三元配合物邻菲咯啉

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尽快谋划和建立符合中国利益的全球创新体系

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科技创新与生产力 2011年第11期 25-30页

作者：赵刚中国科学技术发展战略研究院北京100038

近年来,中国的创新能力不断提高,但与发达国家相比差距仍然明显,中国应顺应创新环境变化,借机构建符合自身利益的全球创新体系。在此背景下,中国需洋为中用,借鉴美国、欧盟、日本等发达国家的创新经验,统筹部署,全面推进政府间科技合作... 详细信息

近年来,中国的创新能力不断提高,但与发达国家相比差距仍然明显,中国应顺应创新环境变化,借机构建符合自身利益的全球创新体系。在此背景下,中国需洋为中用,借鉴美国、欧盟、日本等发达国家的创新经验,统筹部署,全面推进政府间科技合作,积极承接跨国公司研发国际转移,广泛参与国际大科学工程与计划,大力实施人才国际化战略,提升中国在全球创新体系中的地位。

关键词：创新能力创新环境全球创新体系

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