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china plastics Industry (2005)

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中国塑料 2006年第4期 2-7页

作者： LIAO Zheng-pin (china plastics processing Industry Association, Beijing 100740, china china National Technical Committee of Standardization for plastics products, Beijing 100037, china Expert Committee of china plastics processing Industry Association, Beijing 100740, china) Zhang Yuxia

With the steady, continuous and healthy development of china economics, china plastics industry advanced at a great stride during the 10th Five-year plan period. Now the outputs of plastics machinery, plastics products and synthetic resins are listed the first place, the second place and the third place in the world, respectively. Simultaneously, the innovative capacity of the in-

关键词： In china plastics Industry over more pVC rate 230 than

Dynamic mechanisms of the post-seismic deformation following large events:Case study of the 1999 Chi-Chi earthquake in Taiwan of china

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Science china Earth Sciences 2009年第11期52卷 1813-1824页

作者： ZHU ShouBiao1,2 & CAI YongEn2 1 Institute of Crustal Dynamics, china Earthquake Administration, Beijing 100085, china 2 Department of Geophysics, p.king University, Beijing 100871, china 1. Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China 2. Department of Geophysics Peking University Beijing 100871 China

The mechanism of postseismic deformation related to strong earthquakes is important in geodynamics, and presumably afterslip or viscoelastic relaxation is responsible for the postsesimic deformation. The 1999 Chi-Chi, Taiwan of china, earthquake occurred in the region where GpS observation station is most densely deployed in the world. The unprecedented GpS data provides a unique opportunity to study the physical processes of postseismic deformation. Here we assume that the interactions of viscoelastic relaxation, afterslip, fault zone collapse, poroelastic rebound, flow of underground fluids, and all these combined contribute to the surface displacements following the main shock. In order to know the essence of the postseismic deformation after the strong event, fault zone collapse, poroelastic rebound, flow of underground fluids, and so on, are represented equivalently by the variations of the focal medium properties. Therefore, the viscoelastic relaxation, afterslip, and the variations of the equivalent focal medium properties are inverted by applying the GpS temporal series measurement data with viscoelastic finite element method. Both the afterslip rate distribution along the fault and the afterslip evolution with time are obtained by means of inversion. Also, the preliminary result suggests that viscosities of the lower crust and the upper mantle in Taiwan region is 2.7×1018 and 4.2×1020 pa·s, respectively. Moreover, the inversion results indicate that the afterslip contributing to postseismic deformation of 44.6% in 450 days after the Chi-Chi earthquake, with 34.7% caused by the viscous relaxation and 20.7% by other factors such as fault zone collapse, poroelastic rebound, and the flow of liquids.

关键词： mechanism of postseismic deformation viscoelastic finite element method GpS temporal series data Chi-Chi earthquake

Mechanism of the Spring persistent Rains over southeastern china

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Science china Earth Sciences 2007年第1期50卷 130-144页

作者： WAN RiJin1,2,3 & WU GuoXiong1 1 State key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Mechanicals (LASG), Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 100029, china 2 Guangdong Climate and Agrometeorology Center, Guangzhou 510080, china 3 Shanghai Typhoon Institute of china Meterological Administration, Shanghai 200030, china 1. State key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Mechanicals (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Guangdong Climate and Agrometeorology Center Guangzhou 510080 China 3. Shanghai Typhoon Institute of china Meterological Administration Shanghai 200030 China

The Spring persistent Rains (SpR) in the areas to the south of middle and lower reaches of the Yangtze River or over southeastern china (SEC) is a unique synoptic and climatic phenomenon in East Asia. This study reveals a possible mechanism responsible for the climatic cause of SpR formation through climatic mean data analysis and sensitive numerical model experiments. SEC is located at the down-stream of the southwesterly velocity center (SWVC) which lies on the southeastern flank of the Tibetan plateau (Tp). As a result, there are strong southwesterly wind velocity convergence and moisture con-vergence over SEC. This is the immediate climatic cause of SpR formation. In spring, the seasonal evolution of the southwesterly velocity consists with the surface sensible heating over southeastern Tp, indicating that the formation of SpR is related to not only the southwesterly wind of mechanical de-flected flow of Tp, but also the southwesterly wind of thermal-forced cyclonic low circulation. Sensitive numerical experiments demonstrate that, without Tp, both SWVC and the SpR rain belt will disappear. The southwesterly wind velocity increases almost linearly with the amount of the total diabatic heating with Tp rising. Therefore, SWVC is the result of the mechanical forcing and thermal forcing of Tp. All these strongly suggest that the presence of Tp plays a primary role in the climatic formation of SpR.

关键词： SpR climatic cause of formation southwesterly Tibetan plateau sensitive experiments.

Responses of ground-dwelling spiders to four hedgerow species on sloped agricultural fields in Southwest china

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progress in Natural Science:Materials International 2009年第3期19卷 337-346页

作者： Yuhong Wu a, Qingnian Cai b, Chaowen Lin c, Yibing Chenc, Yuying Lid, Xu Cheng b,* a College of Resources and Environmental Sciences, china Agricultural University, Beijing 100193, china b College of Agriculture and Biotechnology, china Agricultural University, Beijing 100193, china c Institute of Soils and Fertilizers, Sichuan Academy of Agricultural Sciences, Chengdu 610066, china d College of Life Science and Technology, Nanyang Normal University, Nanyang 473061, china [a]College of Resources and Environmental Sciences China Agricultural University Beijing 100193 China [b]College of Agriculture and Biotechnology China Agricultural University Beijing 100193 China [c]Institute of Soils and Fertilizers Sichuan Academy of Agricultural Sciences Chengdu 610066 China [d]College of Life Science and Technology Nanyang Normal University Nanyang 473061 China

Spiders are important predators in agroecosystems and contribute to the control of agricultural pest populations. Habitat manage- ment such as the creation of new semi-natural habitats around or within fields enhances spider abundance and species diversity. Using pitfall traps, we investigated the effects of four hedgerow plant species, which serve as undisturbed and permanent semi-natural habitats, on ground-dwelling spider activity density (a parameter of population density and relative activity) and species richness. Samples were collected over two winter wheat and two summer maize growing seasons during 2005-2007 in trial field 1 (slope gradient of 20%) and field 2 (slope gradient of 12%) at the Ziyang Experimental Site in Sichuan province, china. The hedgerow species evaluated were Amorpha fruticosa (field 1), Vetiveria zizanioides (field 1), Eulaliopsis binata (field 2), and Medicago sativa (field 2). Compared to control plots, hedgerow plots had significantly higher activity density and species richness of ground-dwelling spiders within strips in both fields 1 and 2 during the wheat growing season. The presence of hedgerow strips did not augment the activity density and species richness of ground-dwelling spiders within the crop fields during the wheat or maize growing seasons. The ground-dwelling spider activity density within hedgerow strips was significantly higher in the Vetiveria than in the Amorpha plots and in the Medicago than in the Eulaliopsis plots, and the species richness was significantly higher in the Vetiveria than in the Amorpha plots during the wheat season. Our results suggest that hedgerows may serve as important overwintering sites for ground-dwelling spiders during the wheat growing season. In addition, the diversification of agroecosystems by using hedgerow strips may be a viable strategy for maintaining ground-dwelling spider populations in agricultural areas. However, ground-dwelling spiders did not move into adjacent crop fields; the

关键词： Activity density Araneae Ground-dwelling Hedgerow pitfall trapping Species richness

Infragravity waves with internal wave characteristics in the south of the Bohai Sea of china

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Acta Oceanologica Sinica 2003年第2期22卷 171-178页

作者： Fan Zhisong, Gao Guoping, Yin Xunqiang, Fan Yu, Wu Wei Marine Environment College,Ocean University of china,Qingdao 266003, china Ocean Univ china Marine Environm Coll Qingdao 266003 Peoples R China

The measurements by using ADCp (500 kH) and CTD were made during August 2000in the south (37?5'N, 120?5'E) of the Bohai Sea, where the water depth was about 16.5 m. The data of horizontal velocity with sampling interval of 2 min in 7 layers were obtained. The power spectrum analysis of these data indicates that there are very energetic infragravity waves with a period of about 6 min. The coherence spectrum analysis and the analysis of temporal variation of shear show that these infragravity waves are mainly the free wave model (properties of edge waves), in the meantime they possess some characteristics of internal waves, which are likely due to the distinctive marine environment in this area. It is speculated on that the instability processes (chiefly shear instability) of sheared stratified tidal flow owing to the effect of sea-floor slope in the coastal area might be the main mechanism generating these infragravity waves.

关键词： Infragravity waves edge waves internal waves vertical shear of horizontal velocity internal mixing

Shenzhousia qilianshanensis gen. et sp. nov. (protodonata, Meganeuridae), a giant dragonfly from the Upper Carboniferous of china

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progress in Natural Science:Materials International 2006年第3期16卷 328-330页

作者： ZHANG Zhijun, HONG Youchong, LU Liwu, FANG Xiaosi and JIN Yuegao (Department of palaeontology, the Geological Museum of china, Beijing 100034, china Beijing Museum of Natural History, Beijing 100050, china) [a]Department of palaeontology The Geological Museum of China Beijing China [b]Beijing Museum of Natural History Beijing China

A new dragonfly of family Meganeuridae Shenzhousia qilianshanensis gen. et sp. nov., discovered from Ningxia Hui Autonomous Region in North china, is described in the present paper. It has an estimated wingspan of about 450-500mm and may be the largest fossil insect in Late Carboniferous Namurian Stage discovered by far. The new species is referred to Meganeuridae because of the presence of the characteristic oblique vein between anterior branch of radius (RA) and posterior branch of radius (Rp) near the base of Rp2. It differs from other genera within the family in the following characteristics: precostal area short and not extending to the midwing; posterior branch of subcostal vein short, merging into costal vein near the level of originating point of IR2; Rp forking earlier than anterior branch of media basally; Rp1+2 and Rp3+4 parallel and close to each other for a long distance, and then diverge gradually surpass midwing.

关键词： Namurian Meganeuridae Ningxia Hui Autonomous Region Upper Carboniferous Tupo Formation.

Investigation of integrons/cassettes in antimicrobial-resistant Escherichia coli isolated from food animals in china

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Science china(Life Sciences) 2010年第5期53卷 613-619页

作者： SONG Li1,NING YiBao1,SHEN JianZhong2,FAN XueZheng,ZHANG Chunping1,YANG ChengHuai1 & HAN JianFeng3 1 china Institute of Veterinary Drug Control,Beijing 100081,china 2 china Agricultural University,Beijing 100094,china 3 china Center for Disease Control and prevention,Beijing 100050,china 1. china Institute of Veterinary Drug Control Beijing 100081 China2. China Agricultural University Beijing 100094 China3. China Center for Disease Control and Prevention Beijing 100050 China

In this study,326 Escherichia coli isolates from food animals collected during the last four decades in china were characterized using antimicrobial susceptibility testing and screening for integrons/*** inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of *** has increased since the *** findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in china.

关键词： E.coli Antimicrobial resistance integron/cassette last four decades

Comparative analysis of temperature and CO2 fluxes for winter wheat in Tibetan plain and North china plain using the EMD method

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progress in Natural Science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI Shuhe, WANG Tianduo, SUN Xiaomin and ZHANG Renhua ( Chinese Academy of Meteorological Science, Beijing 100081, china Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china Mathematics Department, Ocean University of china, Qingdao 266071, china Shanghai Institute of plant physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, china) [a]Chinese Academy of Meteorological Science Beijing China [b]Chinese Academy of Sciences Institute of Geographic sciences and Natural Resources Research Beijing China [c]Mathematics Department Ocean University of China Qingdao China [d]Chinese Academy of Sciences Shanghai Institute of Plant Physiology and Ecology Shanghai China

Comparative study of spectral properties of temperature and CO2 fluxes measured by eddy covariance method at Yucheng (36°57'N, 116°36'E, 28 m a.s.l., in the North china plain) and at Lhasa (29°41'N, 91°20'E, 3688 m a.s. 1., on the Tibetan plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1) The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2 fluxes (F) measured at Yucheng ( T1 and F1) and Lhasa ( T2 and F2) . (2) Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2 fluxes in North china plain and on Tibetan plain illustrated that the characteristic frequencies corresponding to T1, F1, T2 and F2 are 0.05 Hz, 0.03 Hz, 0.014 Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

Surface deformation at the epicenter of the May 12,2008 Wenchuan M8 Earthquake,at Yingxiu Town of Sichuan province,china

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Science china(Technological Sciences) 2008年第S2期51卷 154-163页

作者： DONG Shaopeng,HAN ZhuJun & AN YanFen National Center of Seismic Fault Study,Institute of Geology,china Earthquake Administration,Beijing 100029,china 1. National Center of Seismic Fault Study Institute of Geology China Earthquake Administration Beijing 100029 China

Surface deformation,along National Highway 213 at the epicenter of Wenchuan M8 earthquake,at Yingxiu Town of Sichuan province,china,is surveyed and measured in *** results show two distinct *** is that no horizontal displacement displays,or dextral strike-slip component at the observation point can not be found basically,the other is that uplift amount is 2.72 m,and the short-ening amount is 0.38 m,which reflects thrust shortening deformation is not *** crust uplift amount of 2.71 m is distributed in a belt with width of 60 *** model of lower crustal flow proposed by Royden et al.(1997) about the dynamic process in eastern margin of the Tibetan plateau seems more suitable to explain the seismic surface deformation characteristics at Yingxiu Town,the epicenter of the May 12,2008 Wenchuan M8 Earthquake.

关键词： Wenchuan M8 Earthquake Yingxiu Town surface deformation