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Geographical Agglomeration of chinese Manufacturing Industries

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中国人口·资源与环境：英文版 2007年第2期5卷 3-11页

作者： Zhang Hua 1, 2, Zheng Wei3.1. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, {3. 2. Graduate School of the chinese academy of sciences, beijing 10003., {3. 3. School of Geography, beijing Normal University, beijing 100875, {3. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100039 China School of Geography Beijing Normal University Beijing 100875 China

Based on the plant level data from the First National Census of Basic Units, the Second National Census of Basic Units, and the First National Economic Census of china, this paper ex- amines the geographical agglomeration of chinese manufacturing industries at a more disaggregated level both by industrial classi-fication and spatial unit analysis. Applying the agglomeration index proposed by Maurel and Sedillot, studies show that the most agglomerated industries are resource-intensive, and capital and technology intensive while industries demanding localized inputs or serving localized markets or favored by local governments are fairly dispersed. The more disaggregated industries are more spa- tially agglomerated. At the finer spatial scale, industries are more dispersed. Results indicate that within-county spillovers are stronger than nearby-county spillovers, and within-prefecture spillovers are stronger than nearby prefecture spillovers. Local- ized spillovers are still quite substantial at a range beyond that of counties. Comparing the agglomeration index of chinese manu- facturing industries in 1996, 2001 and 2004, agglomeration seems to be a general tendency. Results also indicate that some industries have experienced remarkable changes in their levels of agglom- eration in the period 1996–2004.

关键词： industrial agglomeration manufacturing industries the MS index

CONVERGENCE OF VORTEX METHODS FOR 3.D EULER EQUATIONS

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Journal of Computational Mathematics 2000年第3期18卷 239-250页

作者： Jia-fu Lin (Institute of System Science, academy of Mathematics and System sciences, chinese academy of sciences, {3., 100080, china School of Mathematical sciences, Peking University, {3. 100871, china) 中科院系统科学所北京 100080

Presents a study on the convergence of vortex methods for the three-dimensional Euler equations in bounded domains. Related studies on the convergence of vortex methods; Formulation of vortex methods; Convergence for ... 详细信息

关键词： Euler equations vortex methods convergence initial-boundary value problem

Determination of atmospheric concentrations of halocarbons in beijing area

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Journal of Environmental sciences 1993年第1期5卷 76-82页

作者： Wang ShaobinResearch Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, {3.Peng Lixin and Tang XiaoyanResearch Center of Environmental sciences, Peking University, beijing 100871, {3. Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over beijing. Halogenated compounds such as CFC-11, CFC-12, CHCl_3. CCl_4, CH_3.Cl_3. CHCl =CCl_2, and CCl2=CCl2 were measured and their concentrations are 109±8, 23.±13. 47±22, 97±24, 88±29, 11±1 and 17±3.(pptv), respectively.

关键词： GC-ECD atmospheric halocarbons beijing.

RECOVERY OF AMORPHOUS POLY(ETHYLENE TEREPHTHALATE)FILM UNIAXIALLY DRAWN JUST BELOW THE GLASS TRANSITION TEMPERATURE

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chinese Journal of Polymer Science 2000年第1期18卷 69-75页

作者： Nan-jian Sun Juan Yang De-yan Shen Ren-yuan Qian Institute of chemistry, chinese academy of sciences, beijing 100080, {3. 中科院化学所北京

Isothermal recovery in the macroscopic length of homogeneously deformed specimens of amorphous poly(ethylene terephthalate) (PET) film sample uniaxially drawn at 69 degrees C to the draw ratios lambda(0) = 1.26-2.20 were studied at temperatures around the glass transition temperature (T-g = 73.degrees C). Experimental results indicate that the length recovery look place in two distinct steps: a fast first step (fast relaxation) followed by a slow second step (slow relaxation). The relaxation processes were accompanied by the reversion of trans-conformers (13.0 cm(-1)) to gauche, and the dichroic function of the 13.0 cm(-1) band characterizing the segmental orientation along the chain direction decreased to a very low value at the end of the fast relaxation. This fact led us to assign the fast relaxation as the segmental orientation while the slow relaxation as relaxation of the global chain orientation. It was found that the slow relaxation follows a single exponential function, with relaxation times strongly dependent on the temperature resembling the glass transition process. The fast relaxation does not follow a single exponential decay, presumably a distribution of relaxation times is involved.

关键词： poly(ethylene terephthalate) uniaxial drawing recovery orientation

Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in china

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2,3.Sheng-Bin CHEN § 1 Gao-Ming JIANG 3.Zhi-Yun OUYANG 3.Wei-Hua XU 3.Yi XIAO 1 (State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of sciences, beijing 100093. china) 2 (Graduate University of the chinese academy of sciences, beijing 100049, china) 3.(State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China)

Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from china, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

Size-dependent hydroxyl radicals generation induced by SiO_2 ultra-fine particles: The role of surface iron

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Science china chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1, ZHU Tong1, LI Yi1,2 & ZHAO JinCai3.1 College of Environmental sciences and Engineering, Peking University, beijing 100871, china 2 {3. academy of Meteorological sciences, beijing 100871, china 3.Institute of chemistry, chinese academy of sciences, beijing 100871, china College of Environmental sciences and Engineering Peking University Beijing China chinese academy of Meteorological sciences Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM10). The ultra-fine fraction of PM10 has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capability of dif-ferent sizes of SiO2 particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2 particles with diameters of 14, 100, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 14 nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2 = 0.812, p<0.01). Washed particles, with their surface iron being removed, did not generate ·OH. The iron-containing leachate from these washings was able to enhance ·OH production as untreated particles did. Therefore, the presence of adsorbed iron on the surface of the SiO2 particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2 acted as an inert substrate, and the surface of ultra-fine SiO2 particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect

OsFKBP1 interacts with phytochrome B in rice

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Progress in Natural Science:Materials International 2009年第11期19卷 1523-1528页

作者： Suhai Gu,Fang Zhang,Naihu Wu~* Institute of Genetics and Developmental Biology,chinese academy of sciences,3.Zhongguancunnanyitiao,beijing 100080,china Institute of Genetics and Developmental Biology Chinese Academy of Sciences 3 Zhongguancunnanyitiao Beijing 100080 China

Part of the C-terminal of rice phytochrome B was used as bait to screen a cDNA library constructed from young rice panicles in a yeast two-hybrid screening.A positive clone was selected,and the sequence was characterized as encoding a FKBP protein,which is a putative developmental *** in vitro pull-down assay using recombinant proteins and analysis of bimolecular fluorescence complementation in onion epidermal cells indicated that two proteins interact in vitro and in *** results of reverse transcription polymerase chain reaction showed that two genes were co-expressed in the examined rice organs,suggesting that OsFKBP1 may play a role in light signal transduction in rice.

关键词： Rice Yeast two hybrid Phytochrome BiFC

A TRUST REGION METHOD FOR SOLVING DISTRIBUTED PARAMETER IDENTIFICATION PROBLEMS

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Journal of Computational Mathematics 2003年第6期21卷 759-772页

作者： Yan-fei Wang Ya-xiang Yuan(LSEC, ICMSEC, academy of Mathematics and System sciences, chinese academy of sciences,{3., china) 中科院数学与系统科学院 LSEC ICMSEC CAS 北京 100080

This paper is concerned with the ill-posed problems of identifying a parameter in an elliptic equation which appears in many applications in science and industry. Its solution is obtained by applying trust region method to a nonlinear least squares error problem. Trust region method has long been a popular method for well-posed problems. This paper indicates that it is also suitable for ill-posed problems. Numerical experiment is given to compare the trust region method with the Tikhonov regularization method. It seems that the trust region method is more promising.

关键词： Parameter identification Ill-posed problems Trust region.

Magnetic order in Cr_(73.7)(Fe_(0.83.Mn_(0.17))_(26.3.alloy

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chinese Science Bulletin 1997年第4期42卷 282-285页

作者： XU WeimingCryogenic Laboratory, chinese academy of sciences, beijing 100080, china Cryogenic Laboratory Chinese Academy of Sciences Beijing China

WITH the temperature decreasing, Cr100-xFex（18≤x≤25） alloys exhibit first a transition from a paramagnetic （PM） state to a ferromagnetic （FM） state and then a second transition from the FM state to a re-entran... 详细信息

关键词： Mossbauer spectrum magnetic order clusters re-entrant spin glass.