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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

Science china Earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2.1. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, {2. 100101, china 2. Laboratory for Earth Surface Processes, Peking University, {2. 100871, china 1. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952.2.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952.1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92. of total transfer fluxes of HCHs isomers. There were approximately 2.3t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 2. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

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Floating Population Increase and Its Influence on the Urban Population Situation:A Case Study in beijing

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chinese Journal of Population,Resources and Environment 2005年第1期3卷 27-35页

作者： Wu Peilin 1,2.& Lu Qi 2.1. Shandong University of Technology, Zibo Shandong 2.5049, china 2. Institute of Geographical sciences and Natural Resources Research,{2., beijing 100101, china Shandong University of Technology Zibo Shandong 255049 China Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Floating population is a special population group in china resulting from the implementation of household registration system. This paper uses a set of floating population survey data, population censuses data and statistical data to analyze the increase and influence of floating population on the urban population situations in beijing. It is found that beijing has experienced a rapid increase of floating population since the 1990s and that the increase of this group has become the key factor of the current population expansion in the city. Its distribution in the urban regions intensified and extended the suburbanization process of the capital. In addition, the population structures of sex, age, education and employment in beijing have changed to some extent due to the influx of floating population.

关键词： Floating population Household registration system (Hukou) Population expansion Suburbanization Population structure beijing

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Recent beijing Spectroscopy (BES) results

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Science china(physics,Mechanics & Astronomy) 2008年第6期51卷 567-576页

作者： LI WeiGuo Institute of High Energy physics, chinese academy of sciences, {2. 100049, china 1. Institute of High Energy physics Chinese Academy of Sciences Beijing 100049 China

Recent experimental results from beijing Spectroscopy (BES) are reviewed, including the hadron spectroscopy from J/ψ decays, and a number of new states are found or confirmed, including σ, κ, X(1835), ωφ threshold enhancement in J/ψ→γωφ, a broad resonance in J/ψ→K + K ? π 0, decay studies of ψ(2.) and χ CJ , as well as the results of ψ(3770) non-D $ \bar D $ decays. The current status of BEPCII/BESIII, the major upgrade of BEPC/BESII, is also reported.

关键词： beijing Spectroscopy hadron spectroscopy charm physics BEPCII

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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 1. College of Science China Agricultural University Beijing 100083 China 2. Institute of physics Chinese Academy of Sciences Beijing 100080 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

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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,{2. 2. Institute of Environmental sciences, beijing Normal University, beijing 100875,{2.) 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)

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Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. Institute of Engineering Thermophysics, chinese academy of sciences,{2., china 2. Graduate School, chinese academy of sciences,{2., china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. Graduate School Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

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Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3 , YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, china 2. Center for Condensed Matter physics, Institute of physics, chinese academy of sciences, beijing 100080, china 3. BSRF, Institute of High Energy physics, chinese academy of sciences, beijing 100039, china 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

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Estimating possible impact of human activity on the warm season temperature in beijing since the industrial era

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chinese Science Bulletin 2010年第16期55卷 1590-1593页

作者： QIN Li1,2.& ZHOU Xin1,2.1 Institute of Geology and Geophysics,chinese {2. of sciences,beijing 10002.,china 2.Graduate University of chinese academy of sciences,beijing 100049,china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Global surface temperature shows an increasing trend over the past 100 *** and natural factors have been invoked to explain this warming, but their relative contribution and the spatial variability remain *** on a 2.50-year temperature record from a stalagmite near beijing, we explore the possible impacts of human activity on the warm season temperature in beijing since the industrial era using the method of singular spectrum analysis (SSA).The results suggest that the warm season temperature in beijing under the natural forcing should have an overall decreasing trend for the past 130 years (1870 to 2.00 AD) with an amplitude of 0.45±0.84°C, while the instrumental record and stalagmite data show an increase of 1.08°*** imply that human activity would have caused an increase in the warm season temperature of beijing for about 1.53±0.84°C compared to its natural trends, from 1870 AD to 2.00 *** results also suggest that anthropogenic forcing began to significantly influence the temperature since 1870 AD, and the effect further intensified since 1915 AD.

关键词：人类活动北京温度工业时代季节温暖估计地表气温

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Some key technics of drop tower experiment device of National Microgravity Laboratory (china) (NMLC)

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Science china(Technological sciences) 2005年第3期48卷 305-316页

作者： ZHANG Xiaoqian 1 , YUAN Longgen 1 , WU Wendong 1 , TIAN Lanqiao 2.& YAO Kangzhuang 2.1. Institute of Engineering Thermophysics, chinese academy of sciences,{2., china 2. Institute of Mechanics, chinese academy of sciences,{2., china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China

Drop tower is an important ground based facility for microgravity science experiment. The technical performances of the drop tower NMLC are advanced compared with similar facilities in the US, Germany and Japan. The main components such as drop capsule, deceleration devices, release mechanism present its advantages and creativities.

关键词： drop tower facility,drop capsule,deceleration devices,release mechanism.

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Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1, GOU Chenhua1, 2.& ZHANG Na1 1. Institute of Engineering Thermophysics, chinese academy of sciences,{2., china 2. Graduate School, chinese academy of sciences,{2., china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Graduate School Chinese Academy of Sciences 10080 Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

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