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Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3 & WANG Huijun2 1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 2. Department of Atmospheric Science, Yunnan university, Kunming 650091, china 3. graduate university of the chinese academy of sciences, beijing 100049, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China graduate university of the chinese academy of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Terrestrial transect study on driving mechanism of vegetation changes

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Science china Earth sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1,2 & ZHOU GuangSheng1 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of sciences, beijing 100093, china 2 graduate university of chinese academy of sciences, beijing 100049, china State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

In terms of chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in china from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast china Transect (NECT) and the North-South Transect of Eastern china (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

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Journal of Systematics and Evolution 2011年第6期49卷 539-545页

作者： 1,2Hong YAO 1Yi-Bo LUO 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) 2(graduate university of the chinese academy of sciences,beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of the chinese academy of sciences Beijing 100049 China)

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3-4 hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2 h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

A revision of Clematis ***(Ranunculaceae)

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Journal of Systematics and Evolution 2009年第6期47卷 552-580页

作者： ~(1,2)Wen-Jing YANG ~1Liang-Qian LI~* ~3Lei XIE 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) 2(graduate university of chinese academy of sciences,beijing 100049,china) 3(Southwestern china Germplasm Bank of Wild Species,Kunming Institute of Botany chinese academy of sciences Kunming 650204,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of chinese academy of sciences Beijing 100049 China) (Southwestern china Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Clematis *** is revised in this paper based on the examination of a large number of herbarium specimens,extensive field observations,and morphometric *** taxonomic history and geographical distribution of the section are given,the relationships among the species are discussed,and the evolutionary trends of some characters in the section are *** staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing ***,they may have evolved in two different *** possibility is that the staminodes elongate and become lanceolate,as long as sepals,and their apices turn into *** other is that the staminodes are spathulate,but not elongating,as long as stamens,and their apices turn into retuse from obtuse and *** evolutionary trend of sepals may be from thin to thick in texture,and the veins from non-prominent to *** a result,five new series are established and nine species, two subspecies and nine varieties(including three new ranks) are recognized in this *** identification key is provided,and each taxon is described and *** sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of,or few,overlapping *** fusijamana and Clematisfauriei are recognized as varieties of *** *** for the continuous variation of the velutinous strips on the sepal *** iliensis is treated as variety of *** *** for the continuous variation of leaf division *** variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis *** North American *** may be primitive,whereas *** may be the most advanced taxon in this *** and *** are closely related to each ***,the systematic position of se

关键词： Clematis sect.Atragene Ranunculaceae taxonomic revision

Effects of the grain size distribution on the temperature-dependent magnetic susceptibility of magnetite nanoparticles

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Science china Earth sciences 2010年第7期53卷 1071-1078页

作者： ZHAO XiangYu1,2 & LIU QingSong1 1 Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2 graduate university of chinese academy of sciences, beijing 100049, china Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

Magnetite is an important magnetic remanence carrier in natural samples and therefore is of great interest in paleo-, rock-, and environmental magnetism. The magnetic properties of magnetite depend on many factors, e.g., concentration and grain size distribution (GSD). In this study, we theoretically investigated the temperature-dependent susceptibility (TDS) of magnetite nanoparticles with a lognormal GSD. Results show that the TDS is affected highly by the GSD mainly in three aspects. Firstly, the unblocking process becomes smoother with the increase of distribution width, characterizing as a wider Hopkinson peak on the TDS curve. Secondly, the blocking temperature increases with the increase of the median diameter or/and the distribution width. Thirdly, the maximum susceptibility decreases with the increase of distribution width, and has a logarithmic function relation with the standard deviation of the distribution. As a case study, this model was further applied to the thermal products of the chinese loess/paleosol samples to determine the granulometry of newly-formed magnetite upon heating based on TDS curves. The results demonstrate the fidelity and feasibility of this method to determine the GSD of nano-sized magnetic particles.

关键词： Néel theory temperature dependence of susceptibility grain size distribution

CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

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Science china Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1, LUO GuangQiang1,2 & YUAN GuoFu1 1 Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 2 graduate university of chinese academy of sciences, beijing 100049, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51 (aboveground plants were excluded), and 2.00 mg m?2 d?1 (all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3,JIN ZHi1,2 & WU Budan1,4 1. academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080, china 2. Institute of Computing Technology, chinese academy of sciences, beijing 100080, china 3. Institute of Software, chinese academy of sciences, beijing 100080, china 4. graduate university of chinese academy of sciences, beijing 100049, china academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Institute of Software Chinese Academy of Sciences Beijing China Institute of Computing Technology Chinese Academy of Sciences Bejing China graduate university of chinese academy of sciences Beijing China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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Science china Chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin College of Chemistry and Chemical Engineering,graduate university of chinese academy of sciences,beijing 100049,china College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

中国政治经济学年度发展报告（2023）（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,Research Institute for 21st-Century Marxism,Nankai university·university of chinese academy of Social Science Center for Teaching and Research on Capital,Renmin university of china National Institute of Socialist Political Economy with chinese Characteristics,Renmin university of china 南开大学·中国社会科学院大学21世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2023年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2023年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2023）》。自2010年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2023年报告聚焦12个专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12由报告（下）篇刊登。2023年报告（下）选题如下：

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