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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 {2. of {3., beijing 100093. China) 2.(Graduate University of the chinese {2. of {3., beijing 100049, China) 3.(State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental {3., chinese {2. of {3., 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 {2. 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 {2. dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a {2.er 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 {2.lights 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.

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science China(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2.3.1. China institute of Atomic {2., {2. 102.13. China 2. Center of Nuclear Theoretical {3., National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 73.000, China 3. institute of Theoretical {3., chinese academy of {12., {2. 100080, China Correspondence should be addressed to Rong Jian (email: jrong@***) China institute of Atomic energy Beijing China Center of Nuclear Theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China institute of Theoretical physics Chinese Academy of Sciences Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Prediction method for October 2.03.solar storm

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Science China(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2. 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, chinese {2. of {2., {3. 100080, China 2. Graduate School, chinese {2. of {2., {3. 10003., China 3. institute of Meteorology, PLA University of Science and Technology, Nanjing 2.1101, China State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China institute of Meteorology PLA University of Science and Technology Nanjing China

Aiming at two intense shock events on October 2. and 2., 2.03. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely {2. temperature, the strong magnetic field, and the {2. speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Deprojection technique for galaxy cluster considering the point spread function

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Science China(physics,Mechanics & Astronomy) 2010年第S1期53卷 183-186页

作者： WANG YuSa,JIA ShuMei & CHEN Yong Key Laboratory for Particle Astrophysics,institute of {2. {3. physics,chinese academy of sciences,beijing 100049,China Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

We present a new method for the analysis of Abell 183. observed by *** method is a combination of the Direct Demodulation technique and *** eliminate the effects of the point spread function(PSF) with the Direct Demodulation *** then use a traditional deprojection technique to study the properties of Abell *** to only using a deprojection method,the central electron density derived from this method increases by 3.%,while the temperature profile is similar.

关键词： PSF Direct Demodulation deprojection Abell 183. galaxy cluster XMM-Newton

Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in China

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Science China Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2.3.HUANG JiKun 1,3.& DENG XiangZheng 1,3.1 institute of Geographic sciences and Natural Resources Research,{2. {3. of sciences,beijing 100101,China 2.Department of Economics and Management,Zhejiang Forestry University,Linan 3.13.0,China 3.Center for {2. Agricultural Policy,{2. {3. of sciences,beijing 100101,China institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Department of Economics and Management Zhejiang Forestry University Linan China Center for chinese Agricultural Policy Chinese Academy of Sciences Beijing China

As a renewable energy,biofuel has attracted great attention in China and the rest of *** with the national food security,China recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in China's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest China

Nucleon Form Factors and N-A Transitions in a Hypercentral Constituent Quark Model with Meson Cloud

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Communications in Theoretical physics 2007年第3期 539-546页

作者： CHEN Dina-Yong~(1,2. DONG Yu-Bing~(1,+)1 institute of high {2. {3.,the chinese academy of sciences,beijing 100049,China2.Graduate School of the chinese academy of sciences,beijing 100049,China institute of high {2. {3.，the chinese academy of sciences，beijing 100049，China Graduate School of the chinese academy of {2.，{3. 100049，China institute of high {2. {3.，the chinese academy of sciences，beijing 100049，China

We study the nucleon form factors and the nucleon-△(12.0})transitions in a framework of hypercentralconstituent quark *** pion meson cloud effect is taken into account *** results show that the pioncloud contributes substantially to the nucleon form factors as well as to the helicity amplitudes of △(12.0}),and it givesan improved agreement compared to the experimental measurement.

关键词： electromagnetic form factor nucleon and △(12.0}) hypercentral constituent quark model meson cloud

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science China Earth sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3. ZHANG RenHe2. SUN ShuFen1, BIAN LinGen2. XIAO CunDe4,2.& ZHANG TingJun5 1 institute of Atmospheric {2., {2. {3. of sciences, beijing 10002., China 2.{2. {3. of Meteorological sciences, beijing 100081, China 3.Graduate University of {2. {3. of sciences, beijing 100049, China 4 Cold and Arid Regions Environmental and Engineering Research institute, {2. {3. of sciences, Lanzhou 73.000, China 5 The National Snow and Ice Data Center, University of Colorado, Boulder, CO 803.9-0449, USA institute of Atmospheric physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of {2. Beijing China chinese academy of Meteorological {2. Beijing China Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China The National Snow and Ice Data Center University of Colorado Boulder USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3. 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the {2.est interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

CHEMICAL STRUCTURE DEPENDENCE OF THE INTERNAL energy CONTRIBUTION IN RUBBER ELASTICITY

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chinese Journal of Polymer Science 2001年第5期19卷 447-449页

作者： Juan Sun Xiao-zhen Yang Polymer physics Laboratory Center for Molecular sciences, {2. of Chemistry{3.beijing 100080 China 中科院化学所高分子物理及化学国家重点实验室北京

Conformational elasticity theory recently developed has been used to explore the internal energy contribution to the elastic force f(e)/f as a function of strain for poly(cis-1,4-isoprene) and poly(trans-1,4-isoprene). Calculated f(e)/f values are in good agreement with those obtained experimentally. Results show that behavior of f(e)/f is mainly contributed by chemical structure, or intramolecular interaction, supporting the experimental observations, and that the internal energy contribution is strain dependent.

关键词： conformational elasticity theory internal energy contribution poly(cis-1,4-isoprene) poly(trans-1,4-isoprene)

Bifurcation timescales in power spectra of black hole binaries and ultraluminous X-ray sources

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Science China(physics,Mechanics & Astronomy) 2010年第S1期53卷 177-182页

作者： WANG TaiShan1 & LI TiPei1,2.1 Department of physics & Center for Astrophysics,Tsinghua University,{2. 100084,China 2.Key Laboratory of Particle Astrophysics,institute of high energy physics,chinese academy of sciences,{2. 100049,China Department of physics & Center for Astrophysics Tsinghua University Beijing China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

For black hole binaries(BHBs) and active galactic nuclei(AGNs),bifurcation timescales(BTs) Δtb exist,below which time-domain power is significantly higher than the corresponding Fourier ***-periodic oscillations(QPOs) are removed from the Fourier spectra of BHBs.A relationship between BT,black hole mass and bolometric luminosity is *** anti-correlation between BT and luminosity of Cyg X-1 is *** removing the QPOs,BTs are also obtained for two ultraluminous X-ray sources(ULXs),M82.X-1 and NGC5408 *** results support that they harbor intermediate mass black holes(IMBHs).

关键词： black hole binary ultraluminous X-ray source power spectral density data analysis