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Report on Cardiovascular Health and Diseases in china 2.2.:An Updated Summary

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Biomedical and Environmental Sciences 2024年第9期37卷 949-992页

作者： National Center for Cardiovascular Diseases The Writing Committee of the Report on Cardiovascular Health and Diseases in china Shengshou Hu .

Since 1990,china has made considerable progress in resolving the problem of“treatment difficulty”of cardiovascular diseases(CVD).The prevalent unhealthy lifestyle among Chinese residents has exposed a massive proportion of the population to CVD risk factors,and this situation is further worsened due to the accelerated aging population in *** remains one of the greatest threats to the health of Chinese *** terms of the proportions of disease mortality among urban and rural residents in china,CVD has persistently ranked *** 2.2.,CVD accounted for 48.98%and 47.35%of deaths in rural and urban areas,*** out of every five deaths can be attributed to *** implement a national policy“focusing on the primary health {2. and emphasizing prevention”and truly achieve a shift of CVD prevention and treatment from hospitals to communities,the National Center for Cardiovascular Diseases has organized experts from relevant fields across china to compile the“Report on Cardiovascular Health and Diseases in china”annually since *** 2.2. report is established based on representative,published,and high-quality big-data research results from cross-sectional and cohort population epidemiological surveys,randomized controlled clinical trials,large sample registry studies,and typical community prevention and treatment cases,along with data from some projects undertaken by the National Center for Cardiovascular *** firsthand data not only enrich the content of the current report but also provide a more timely and comprehensive reflection of the status of CVD prevention and treatment in china.

关键词： Cardiovascular disease Risk factor Prevalence Mortality Rehabilitation Basic research Medical device development Health economics

A circum-earth shear zone at low-latitudes and episodic large earthquakes in it and the circum-Pacific seismic zone

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Science china Earth Sciences 2006年第9期49卷 897-903页

作者： MA Zongjin1, DU Pinren1, REN Jinwei2.& GAO Xianglin1 1. institute of Geology, china Earthquake Administration, {2. 10002., china 2. institute of Earthquake Science, china Earthquake Administration, {2. 100036, china institute of Geology China Earthquake Administration Beijing China institute of Earthquake Science China Earthquake Administration Beijing China

Because of the differential motions between the Northern and Southern Hemispheres of the Earth, there exists a motion discordant zone between them. On the surface this zone consists of 13 large faults dominant with strike-slip. We call it a global shear zone at low-latitudes (E system). By statistical analysis of temporal distribution of earthquakes Mw≥7.5 in the E system and the circum-Pacific (P system) during 1900―2.03, we find that there exist quasi-episodic and alternative activities in and between these two systems. This phenomenon is likely associated with the half-sphere oscillation in dilation and contraction and the change of the Earth’s rotation rate.

关键词： shear zone, circum-Pacific zone, great earthquake, quasi-episode.

Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. College of Science, china Agricultural University, beijing 100083, china 2. institute of Physics, Chinese Academy of Sciences, beijing 100080, china College of Science China Agricultural University Beijing China institute of Physics Chinese Academy of Sciences Beijing China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

KrF Laser-induced Damage to ZrO2.SiO2.Coatings

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Chinese Journal of Lasers 1995年第2期B4卷 161-168页

作者： WANG Naiyan GAO Huailin(china institute of {2. energy, P. O. Box 2.5-7, Bejijng 1.241., china) china Inst of atomic {2. Beijing China

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关键词： KrF laser coating laser-induced coating damage

Three industries and wastewater and COD discharge of beijing

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Journal of Environmental Sciences 2000年第4期12卷 474-477页

作者： WANG Yan 1, WANG Hong rui 2. NING Da tong 2.(1. beijing Municipal Research institute of Environmental Protection, beijing 100037, china 2. institute of Environmental Sciences, beijing Normal University, beijing 100875, china) 北京市环境保护所北京 1 0 0 0 3 北京师范大学北京 1 0 0 875

With the swift development of economy, the water quality of beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater structure in the industrial sectors are analysed and discussed in terms of the indicators, such as direct wastewater\|discharge coefficient, complete wastewater\|discharge coefficient, direct discharge coefficient of COD and complete discharge coefficient of COD, by taking a year of 1990s as the base year. Some countermeasures are studied and the corresponding recommendations are put forward in order to improve the water environment in beijing. This provides a scientific ground for coordinating the relationship between the aquatic environment and economic growth in this city.

关键词： direct wastewater discharge coefficient (DWDC) complete wastewater discharge coefficient (CWDC) direct discharge coefficient of COD(DDC of COD) complete discharge coefficient of COD (CDC of COD)

Analysis on ignition and extinction of n-heptane in homogeneous systems

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Science china(Technological Sciences) 2005年第5期48卷 556-569页

作者： LIU Yongfeng1 & PEI Pucheng2.1. Mechanical and Electrical Engineering Department, beijing institute of Civil Engineering and Architec-ture, beijing 100044, china 2. State Key Laboratory of Automotive Safety and energy, Tsinghua University, beijing 100084, china Mechanical and Electrical Engineering Department Beijing Institute of Civil Engineering and Architecture Beijing China State Key Laboratory of Automotive Safety and energy Tsinghua University Beijing China

To calculate ignition delay times, the governing equations about species and temperature, which are in a closed volume based on the theory of thermal explosion and in a continuously stirred flow reactor, are deducted. The method referred to steady state assumptions is based on the observation that due to very fast chemical processes in combustion problems many chemical species and reactions are in a quasi-steady state or partial equilibrium. When a species is assumed to be in the steady state, the corresponding differential equation can be replaced by an algebraic relation, which reduces the computational costs. The steady state solution of the reactor equations describes the three ignition temperature regimes and get “S-shaped curve”. The reduced simplified 4-step mechanism for n-heptane from 1011 elementary reactions leads with the steady state assumptions to linear differential equations, which is solved. The simulation results of the 4-step reduced mechanism for n-heptane are fitted well with the experiment data. At last, two important parameters are discussed thoroughly and the temperature perturbation is given. It reduces the computational efforts considerably without losing too much accuracy and further supplies numerical methods for turbulent combustion in the diesel engine.

关键词： ignition delay times, thermal runaway, steady state assumptions, continuously stirred flow reactor.

Randomization of protein encoding gene during species evolution

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Chinese Science Bulletin 1998年第4期43卷 299-303页

作者： GE Weiwen 1 and HE Fuchu 2.1. institute of Hygiene and Environment Medicine, Tianjin 300050, china 2. institute of Radiation Medicine, beijing 100850, china institute of Hygiene and Environment Medicine Tianjin China institute of Radiation Medicine Beijing China

Employing chi_square test, the authors observed the bias of 4 kinds of bases’ locating in 3 codon positions in gene sequence, and proved that there is a positive correlation between higher chi_square value and protein coding structure. By this, the observation that genes undergo progressive reduction in chi_values along evolution direction will reflect the progressive randomization of gene structures and the loss of the characteristics of protein coding sequences. The result proposed that during the evolution of life, genes are unexpectedly degenerating.

关键词： chi_square test gene sequence randomization evolution.

Influence of some factors on alpha energy spectrum of^(2.1)Am fire alarm source

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Nuclear Science and Techniques 1999年第1期10卷 11-13页

作者： FENG Gensheng FENG Xinzhan LI Shujuan (china institute of {2. energy, beijing 1.241.) china institute of {2. energy Beijing 102413 China

Several primary factors influencing the alpha energy spectrum of 2.1Am fire alarm source have been studied in order to get better alpha energy spectrum. The results show that the homogeneity and the thickness of metal surface coat and the size of active area of the source have considerable influence on the alpha energy spectrum of the source.

关键词：火警 2.1Am警报源 α-能谱

Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science china Earth Sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1 & GUO Boling2.1. Department of Mathematics, beijing Normal University, beijing 100875,{2. 2. institute of Applied Physics and Computational Mathematics, beijing 100080,{2. Department of Mathematics Beijing Normal University Beijing China institute of Applied Physics and Computational Mathematics Beijing China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.