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Chinese Journal of Population,Resources and Environment 2005年第3期3卷 61-63页

作者： li yinquan china grain research and training center, beijing 100801, china china grain research and training center Beijing 100801 China

From angles of administrative law and private law, the article analyzes relations between environmental right for citizens and the right to use environmental resources owned by company and enterprise and points out three principles to balancing two relations: A principle of equal protection, a principle that general interest is superior to special interest as well as taking an account for special interest, in specific circumstances, for example, in the circumstance that clashes between environmental and economic interests can not be avoided, policy makers can put an emphasis on more important social interest according after considering weight of each interest. Finally, the article reaches a conclusion that china should establish system of environmental right for citizens from legislative and administrative levels so that a harmonious society can be constructed with guarantee.

关键词： environmental right for citizens the right to use environmental resources Company and enterprise

A preliminary study on vegetation-erosion dynamics and its applications

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Science china Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2 , WANG Guangqian 1 , li Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic Engineering, Tsinghua University, beijing 100084, china 2. International research and training center on Erosion and Sedimentation, beijing 100084, china 1. Department of Hydraulic Engineering Tsinghua University 100084 Beijing China 2. International research and training center on Erosion and Sedimentation 100084 Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

Associations of polygenic risk scores with risks of stroke and its subtypes in Chinese

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Stroke & Vascular Neurology 2024年第4期9卷 399-406,I0044-I0065页

作者： Songchun Yang Zhijia Sun Dong Sun Canqing Yu Yu Guo Dianjianyi Sun Yuanjie Pang Pei Pei ling Yang Iona Y Millwood Robin G Walters Yiping Chen Huaidong Du Yan Lu Sushila Burgess Daniel Avery Robert Clarke Junshi Chen Zhengming Chen liming li Jun Lv On behalf of the china Kadoorie Biobank Collaborative Group Department of Epidemiology&Biostatistics School of Public HealthPeking UniversityBeijingChina Department of Dermatology Xiangya HospitalCentral South UniversityChangshaHunanChina Peking University center for Public Health and Epidemic Preparedness&Response BeijingChina Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijingChina Fuwai Hospital Chinese Academy of Medical Sciences BeijingChina Medical research Council Population Health research Unit at the University of Oxford OxfordUK Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxfordUK NCDs Prevention and Control Department Suzhou CDCSuzhouJiangsuChina china National center for Food Safety Risk Assessment BeijingChina State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijingChina 不详

Background and purpose Previous studies,mostly focusing on the European population,have reported polygenic risk scores(PRSs)might achieve risk stratification of *** aimed to examine the association strengths of PRSs with risks of stroke and its subtypes in the Chinese *** Participants with genome-wide genotypic data in china Kadoorie Biobank were split into a potential training set(n=22191)and a population-based testing set(n=72150).Four previously developed PRSs were included,and new PRSs for stroke and its subtypes were *** PRSs showing the strongest association with risks of stroke or its subtypes in the training set were further evaluated in the testing *** proportional hazards regression models were used to estimate the association strengths of different PRSs with risks of stroke and its subtypes(ischaemic stroke(IS),intracerebral haemorrhage(ICH)and subarachnoid haemorrhage(SAH)).Results In the testing set,during 872919 person-years of follow-up,8514 incident stroke events were *** PRSs of any stroke(AS)and IS were both positively associated with risks of AS,IS and ICH(plittle to no improvement in stroke risk prediction and risk *** In this Chinese population,the association strengths of current PRSs with risks of stroke and its subtypes were moderate,suggesting a limited value for improving risk prediction over traditional risk factors in the context of current genome-wide association study under-representing the East Asia

关键词： testing prediction increment

Global analysis theory of climate system and its applications

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Chinese Science Bulletin 2003年第10期48卷 1034-1039页

作者： li Jianping1,2 & CHOU Jifan2,3 1. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china 2. Department of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, china 3. training center for china Meteorological Administration, beijing 100081, china Department of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

DEVELOPMENT OF STEP-POOL SEQUENCE AND ITS EFFECTS IN RESISTANCE AND STREAM BED STABIliTY

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International Journal of Sediment research 2004年第3期19卷 161-171页

作者： Zhao-Yin WANG, Jiang XU and Changzhi li Professor, Dept. of Hydraulic Engineering, Tsinghua University, beijing & Chairman of Advisory Council, International research and training center on Erosion and Sedimentation, 100084, china, Email: zywang@***.M. Phil., Dr. & Post Doctorate research fellow, Dept. of Hydraulic Engineering, Tsinghua University, beijing, 100084, china Dept. of Hydraulic Engineering Tsinghua University Beijing & Chairman of Advisory Council International Research and Training Center on Erosion and Sedimentation 100084 China Dr. & Post Doctorate research fellow Dept. of Hydraulic Engineering Tsinghua University Beijing 100084 China

Experiments were conducted and field investigations were performed to study the development of step-pool sequence and its effects on resistance to the flow and stream bed stability. Step-pool sequence develops in incised channels as a result of streambed erosion, which is compared with sand dunes and armor layer of the role in resistance and streambed protection. The tight interlocking of particles in steps gives them an inherent stability which only extreme floods are likely to disturb. That stability suggests that step-pools are a valid equilibrium form, especially when coupled with their apparent regularity form and their role in satisfying the extreme condition of resistance maximization. The development degree of step-pools, SP, is proportional to the streambed slope. If the incoming sediment load is equal to or more than the sediment-carrying capacity of the flow, there is no bed erosion and thence there are no step-pools. If the flow depth increases and is over the step-height the resistance caus

关键词： Step-pool Streambed stability Erosion Resistance Rate of energy dissipation Manning’s roughness n

Evaluation on abundance or deficiency of avai－lable trace elements in soil of middle area in china and the effect of applying trace element fertilizer

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Journal of Environmental Sciences 1994年第3期6卷 361-372页

作者： li Jiyun liu Xiudi Fan lihong Tong Yiping Yang Junhui(research center for Eco-Environmental Sciences,Chinese Academy of Sciences,beijing 100085,china)

The authors selected the west part of Xinxiang City,Henan Province in the north china plain as a typical region and carried out assessments of the abundanca or deficiency of the trace ele- ments(B,Mn,Mo,Zn,Cu,Fe)in *** can be seen from results that more than 80% of the farmland is deficiency of zinc(lication of trace elements on grain crops is presented.

关键词： evaluation available trace element soil type topography.

Recrystallization of High Carbon Steel during High Strain Rate

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Journal of University of Science and Technology beijing 2001年第1期8卷 55-58页

作者： Di Tang, Qingwu Cai, Yueqin li, Yumei Pu, Yuzhou Zhu National Engineering Rolling center of University of Science & Technology beijing, beijing 100083, china Iron & Steel research Inst. Maan Shan Iron and Steel Co. Ltd., Maan Shan 243000, china Univ Sci & Technol beijing Natl Engn Rolling Ctr Beijing 100083 Peoples R China Maan Shan Iron & Steel Co Ltd Iron & Steel Res Inst Maan Shan 243000 Peoples R China

The recrystallization of high carbon steel during high temperature and high speed rolling has been studied by analyzing the stress-strain curves and the austenite grain size. Isothermal multi-pass hot compression at high strain rate was carried out by Gleeble-200D. The austenite grain size was measured by IBAS image analysis system. The results show that static recrystallization occurred at interpass time under pre-finish rolling, and at the finish rolling stage, due to the brief interpass time, static recrystallization can not be found.

关键词： high strain rate stress-strain curve recrystallization austenite grain

EMBRITTLEMENT OF Fe-Cr-Al ALLOYS AND EFFECT OF Y ADDITION

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Acta Metallurgica Sinica(English Letters) 1993年第2期6卷 129-135页

作者： li Bei WU Shuangxia li Dianchen Baotou research Institute of Rare Earth Ministry of Metallurgical Industry,Baotou,chinaMA Ruzhang University Science and Technology beijing,beijing,china Baotou research Institute of Rare Earth,Ministry of Metallurgical Industry,Baotou 014010,china Baotou research Inst of Rare Earth MMI Baotou China

A high temperature embrittlement occures in Fe-15Cr-4AI and Fe-20Cr-4Al alloys treated over 1000 *** is caused mainly by 475℃ brittleness during *** a secondary treatment at 500℃ was conducted,the 475℃ brittleness developed very *** only 15 rain of the treating,little plasticity was remained for all samples pretreuted at the temper- atures over 1000℃ and cooled in ***,no 475℃ brittleness was generated when pretreating temperature was below 1000℃,Addition of Yttrium can inhibit not only grain growth,but also 475℃ *** the alloys with 0.2—0.4 wt-%Y,after treating at 800—1300℃,the plasticity did not decrease and the properties of furnace cooled samples were not lower than those of water cooled samples.

关键词： Fe-Cr-Al alloy brittleness Yttrium

Corrosion behavior of Mg-Y alloy in NaCl aqueous solution

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Progress in Natural Science:Materials International 2012年第2期22卷 169-174页

作者： Xin Zhang a,b,c,Kui Zhang a,Xia Deng a,Hongwei li b,c,Yongjun li a,Minglong Ma a,Ning li b,c,Yanlong Wang b,c a State Key Laboratory for Fabrication and Processing of Nonferrous Metals,beijing General research Institute for Nonferrous Metals,beijing 100088,china b beijing Engineering research center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,beijing 100072,china c center of Technology,beijing North Vehicle Group Corporation,beijing 100072,china [a] State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China [b] beijing Engineering research center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China [c] center of Technology Beijing North Vehicle Group Corporation Beijing 100072 China

The corrosion behavior of Mg-(0.25,2.5,5,8 and 15)Y alloys in 3.5wt.%NaCl aqueous solution was *** was found that the degree of corrosion deterioration increased with increasing immersion time up to 2 *** modes for the alloys with low and high content of Y element were general corrosion and pitting corrosion,respectively,and the threshold content for the corrosion mode change was 2.5%for the tested *** experimental results showed that the addition of Y refined the grain of the alloy,and the distribution,i.e.,continuous or not,of the Mg24Y5 phases had great effect on the corrosion rate and corrosion mode.

关键词： Mg-Y Corrosion Microstructure

Effects of Ho on the microstructure and mechanical properties of Mg-Zn-Ho-Zr magnesium alloys

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Rare Metals 2011年第2期30卷 131-136页

作者： li Daquan WANG Qudong DING Wenjiang National Engineering research center for Nonferrous Metals Compositions General Research Institute for Nonferrous Metals Beijing 100088 China National Engineering research center of light Alloys Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

The microstructure and mechanical properties of Mg-Zn-Ho-Zr alloys have been investigated in detail. The grain size of the as-cast Mg-Zn-Ho-Zr alloy was greatly decreased by the addition of Ho, and the grain growth during solution treatment was suppressed by Mg-Zn-Ho phases formed at grain boundaries. These thermally stable Mg-Zn-Ho phases could not completely dissolve into the matrix dur- ing solution treatment, and the strengthening effect of solution-plus-ageing treatment weakened. The addition of Ho can greatly enhance the high-temperature elongation of the Mg-Zn-Ho-Zr alloy, but the increase of high-temperature tensile strength was just a little.

关键词： magnesium alloys holmium rare earth additions heat treatment microstmcture mechanical properties