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Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

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Science China(Technological Sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1,3, LOU Decheng1, GAO Zhanjun4. LIU Lei1, LIANG Hongmei1, WANG Qingfeng1, LI Qiang1,3 & MA Mingzhen1,2 1. Key Laboratory of Metastable Materials Science & Technology of Hebei, Yanshan University, Qinhuangdao 066004. China 2. National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 150001, China 3. College of Mechanical engineering, Yanshan University, Qinhuangdao 066004. China 4. chinese academy of engineering, beijing 100038, China 1. Key Laboratory of Metastable Materials Science & Technology of Hebei Yanshan University 066004 Qinhuangdao China 2. College of Mechanical engineering Yanshan University 066004 Qinhuangdao China 3. chinese academy of engineering 100038 Beijing China 4. National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology 150001 Harbin China

Mechanical properties of the Zr4.Ti14.u12.5Ni10Be22.5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-3200 machine at 34. and 375°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr4.Ti14.u12.5Ni10Be22.5 bulk amorphous alloy, mechanical properties, compressive deformation.

Association between Physical Activity and Telomere Length in a North chinese Population： A China Suboptimal Health Cohort Study

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Biomedical and Environmental Sciences 2018年第5期31卷 394-398页

作者： DING Li Xiang ZHANG Yah Hong2 XU Xi Zhu3 ZHANG Jie4.SUN Ming4.LIU Di4.ZHAO Zhong Yao4.ZHOU Yong5 ZHANG Qun6 WANG You Xin4 Department of Orthopedics Surgery Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of Internal Medicine Weifang Material and Child Health HospitalWeifang 261011ShandongChina School of Public Health Taishan Medical UniversityTaian 271016ShandongChina beijing Key Laboratory of Clinical Epidemiology School of Public HealthCapital Medical UniversityBeiing 100069China beijing Institute of Heart Lung and Blood Vessel DiseasesBeijing Anzhen HospitalCapital Medical UniversityBeiing 100029China chinese Center for Disease Control and Prevention Beiing 102206China

Several studies have demonstrated an association between physical activity and telomere length; however, the association remains inconsistent. A cross-sectional study consisting of 588 participants （375 females, median age of 33.8 years） was carried out to investigate the association between telomere length and physical activity in a general population from North China. The results show that relative telomere length is not significantly different in participants in the northern chinese population with different levels of physical activity, either in the model only adjusted for age （F = 2.127, P = 0.120） or in the model adjusted for demographics and lifestyle （F = 1.227, P = 0.294.. The gender-stratified analysis also produced insignificant results. Our study confirmed a non-significant association between physical activity and telomere length in the northern chinese population, which adds to the inconsistent association between physical activity and telomere length across different ethnic populations.

关键词： Physical activity Telomere length Relative telomere length chinese

A CASE OF REFERENCE ON COMPLEXITY

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Journal of Systems Science & Complexity 2003年第3期16卷 289-292页

作者： SONG Jian (chinese academy of engineering, Box 384., beijing 100038, China) chinese academy of engineering Box 3847 Beijing 100038 China

The author argues that the population system of human societies, the highest form of lives on the planet, may serve as standard paradigm for study of complex systems. it turned out to be a well investigable, nonlinearly controllable dynamic system, where census plays pivotal role. The theory has led China to succeed in checking the upsurge of population growth of 1970-80s and remains reliable basis for family-planning policy-making in all countries world-wide. It suggests that statistics could be a powerful tool in studying holistic properties of complex systems.

关键词： Population dynamics complex systems paradigm statistics.

chinese expert consensus on sedation and analgesia for neurocritical care patients

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chinese Medical Journal 2024年第11期137卷 1261-1263页

作者： Linlin Zhang Shuai Liu Shuya Wang Jian-Xin Zhou the National Center for Healthcare Quality Management in Neurological Diseases chinese Society of Critical Care Medicine Working group of the Expert Consensus on Sedation and Analgesia for Neurocritical Care Patients Department of Critical Care Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Department of Critical Care Medicine Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China 不详

Sedation and analgesia therapy are essential in neurocritical care,but there are ongoing controversies surrounding assessment,administration,and *** advances in neurocritical care medicine,updated evidence-based medicine,considering the variability in knowledge and practice,the National Center for Healthcare Quality Management in Neurological Diseases and the chinese Society of Critical Care Medicine organized experts in neurocritical care to form a working group[Supplementary File 1,http://***/CM9/B958]to update the“Expert Consensus on Sedation and Analgesia for Patients with Severe Brain Injury(2013)”.

关键词： analgesia critical advances

Designing regional pattern for ecosystem restoration:A case study

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Science China(Technological Sciences) 2006年第z1期49卷 86-97页

作者： LI Guoqiang , MA Keming, FU Bojie & LIU Shiling State Key Lab of Systems Ecology, Research Center for Eco-environmental Sciences, chinese academy of Sciences, beijing 100085, China Department of Water Environment, China Institute of Water Resources and Hydropower Research, beijing 100038, China School of Environmental Sciences, beijing Normal University, beijing 100875, China 1. State Key Lab of Systems Ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. Department of Water Environment China Institute of Water Resources and Hydropower Research Beijing 100038 China 3. School of Environmental Sciences Beijing Normal University Beijing 100875 China

Designing regional pattern is challenging for ecosystem restoration both in theory and in practice. The present study proposed a new approach to design regional pattern for ecosystem restoration with a case in the arid valley of Upper Minjiang River, SW China. The procedures are: (1) Determine the regional pattern of main environmental factors based on the relationships between the important environmental factors and the main geographical factors generated from DEM data. (2) Overlay the maps of the main environmental factors. (3) Generate a lookup table according to the species selection rule we proposed to link the candidate restoration species to the main environmental factors.(4. Determine the regional pattern of ecosystem restoration by positioning the restoration species in the map of environmental factors according to the lookup table. The regional restoration pattern designed in this way would be applicable not only to restoring a region, but also to predicting the future landscape change.

关键词： environmental factors, GIS, restoration species, Upper Minjiang River Valley.

Influence of Yb^(3+) concentration on the upconversion luminescence of oxyfluoride material doped with Er^(3+)

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Science China(Physics,Mechanics & Astronomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3 1 Institute of Optoelectronic Technology,Key Laboratory of Luminescence and Optical Information (beijing Jiaotong University),Ministry of Education,beijing 10004.,China 2 Department of Physics,chinese People’s Public Security University,beijing {4.,China 3 Physics & engineering Mathematics Department Faculty of Electronic engineering Menufiya University,Menouf 32952,Egypt 1. Institute of Optoelectronic Technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing 100044 China2. Department of Physics Chinese People’s Public Security University Beijing 100038 China3. Physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya University Menouf 32952 Egypt

In this paper,a new upconversion luminescent material co-doped with Erbium and Ytterbium is reported. The upconversion luminescence transition routes and related properties are studied. The results show that the absorption and emission intensities under excitation of 980 nm laser increase with the increase of the Yb3+ concentration. The red emission is stronger than the green emission. The energy transfer process plays an important role in the upconversion mechanism.

关键词： upconversion luminescence Er3+ Yb3+

Iterative implementation of the adaptive regularization yields optimality

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Science China Mathematics 2005年第4期48卷 485-492页

作者： MA Qinghua & WANG Yanfei Department of Information Sciences, College of Arts and Science of beijing Union University, beijing 100038, China National Key Laboratory on Remote Sensing Science, Institute of Remote Sensing Applications, chinese academy of Sciences, beijing 100101, China Department of Mathematics, University of Central Florida, P. O. Box 161364. Orlando, FL 32816-1364. USA 1. Department of Information Sciences College of Arts and Science of Beijing Union University 100038 Beijing China 2. National Key Laboratory on Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China

The adaptive regularization method is first proposed by Ryzhikov et al. for the deconvolution in elimination of multiples. This method is stronger than the Tikhonov regularization in the sense that itis adaptive, i.e. it eliminates the small eigenvalues of theadjoint operator when it is nearly singular. We will show in this paper that the adaptive regularization can be implemented iterately. Some properties of the proposed non-stationary iterated adaptive regularization method are analyzed. The rate of convergence for inexact data is proved. Therefore the iterative implementation of the adaptive regularization can yield optimality.

关键词： ill-posed problems, non-stationary iterated adaptive regularization, optimality.

Research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

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Science China(Technological Sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1,CAO Wei 1,WANG HongMei 1,SUN ShuangKe 2 &CHEN QiuWen 3 1 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,China 2 China Institute of Water Resources and Hydropower Research,beijing 100038,China 3 Research Center for Eco-Environmental Sciences,chinese academy of Sciences,beijing 100085,China 1. Ertan Hydropower Development Company Ltd. Chengdu 610051 China2. China Institute of Water Resources and Hydropower Research Beijing 100038 China3. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 305 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

Atmospheric Mercury Pollution in beijing

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chinese Journal of Population,Resources and Environment 2009年第3期7卷 92-96页

作者： Guo Hongling1,2 1.Institute of Forensic Science,Ministry of Public Security,beijing 100038,China 2.chinese People’s Public Security University,beijing 100038,China Institute of Forensic Science Ministry of Public Security Beijing 100038 China chinese People's Public Security University Beijing 100038 China

The atmospheric mercury pollution in beijing is a serious *** mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemental mercury,divalent mercury and particulate-phase *** studies showed that mercury in beijing's air was higher than the general level of mercury concentration in the *** emission sources were *** emissions,coal burning,vehicle exhaust emissions and waste incineration were thought to be the main sources of atmospheric mercury pollution in *** also meteorology has an effect on atmospheric mercury concentration in *** have been taken to control the emission of mercury into the air in recent years.

关键词： atmosphere mercury beijing