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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, {3. {2. of Sciences, beijing 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the {3. {2. of Sciences, beijing 100049, china 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

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.

Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science china Earth Sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3. LI Jiliang1, SUN Shanxue1 & WANG Xinzheng1 1. institute of Geology and Geophysics, chinese {2. of Sciences, beijing 10002., china 2. institute of Geophysics, chinese Seismological Bureau, beijing 100081, china 3. institute of Deposition Resource, chinese {2. of Geological Sciences, beijing 10003., china 1. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of Geophysics Chinese Seismological Bureau 100081 Beijing China 3. institute of Deposition Resource Chinese Academy of Geological Sciences 100037 Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting

The age of the plant fossil assemblage in the Liuqu Conglomerate of southern Tibet and its tectonic significance

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Progress in Natural Science:Materials International 2006年第1期16卷 55-64页

作者： FANG Aimin1, YAN Zhen1, LIU Xiaohan2. PAN Yusheng1, LI Jiliang1, YU Liangjun1, HUANG Feixing2.and TAO Junrong3.(1.Laboratory of Lithosphere Tectonic Evolution, institute of Geology and Geophysics, {3. {2. of Sciences, beijing 10002., china 2. institute of Tibet Plateau Research, {3. {2. of Sciences, beijing 100085, china 3. institute of Botany, {3. A cademy of Sciences, beijing 100093. china) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Botany Chinese A-cademy of Sciences Beijing 100093 China

The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion, It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post-colli sional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.

关键词： Liuqu conglomerate plant fossils age Eocene Tectonic implications.

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth Sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3.1. institute of Geodesy and Geophysics, chinese {2. of Sciences, Wuhan 43.077, china 2. Graduate School of the chinese {2. of Sciences, beijing 10003., china 3. Unite Center for Astro-geodymics Research, chinese {2. of Sciences, Shanghai 2.003., china 1. institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. Graduate School of the chinese academy of Sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

PHASE STRUCTURE AND PROPERTIES OF EPOXY RESIN MODIFIED BY POLYSILOXANE BEARING PENDANT AMINO GROUPS

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chinese Journal of Polymer Science 2000年第2期18卷 133-138页

作者： Bing Zhang Xiang-luan Liu Ying Huang Center of Molecular Sciences, institute of chemistry, {2. {3. of Sciences, beijing 100080, china chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

Polysiloxane-modified epoxy resins were prepared through the reaction of epoxy resin with polydimethylsiloxanes bearing pendant N-(beta-aminoethyl)-gamma-aminopropyl groups. The morphology and properties of the cured epoxy resins modified by the polysiloxanes were investigated. It was found that the phase structure and properties of the cured epoxy resins depend mainly on the amino group content in the polydimethylsiloxane and the level of the modifier. The change of phase structure in the cured epoxy resin systems was responsible for the dramatic change in their mechanical and surface properties.

关键词： phase structure polysiloxane epoxy resin mechanical property

Transformations and non-degenerate maps

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Science china Mathematics 2005年第z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei institute of Mathematics, academy of Mathematics and System Sciences, {2. academy of Sciences, beijing 100080, china Graduate School, {2. academy of Sciences, beijing 100080, china 1. institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. Graduate School Chinese Academy of Sciences 100080 Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science china(Technological Sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2. ZHANG Taihua1, LI Weihuo3.& WEI Bingchen3.1. State Key Laboratory of Nonlinear Mechanics (LNM), institute of Mechanics, chinese {2. of Sci- ences, beijing 100080, china 2. College of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 3.0074, china 3. National Microgravity Laboratory, institute of Mechanics, chinese {2. of Sciences, beijing 100080, china 1. State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. College of Physics and Electronic Information Science Tianjin Normal University Tianjin 300074 China 3. National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

TRIMETHYLSILYLATED SILICA AS RHEOLOGY MODIFIER FOR SILICONE RESINS

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chinese Journal of Polymer Science 2000年第1期18卷 51-55页

作者： Wei Huang Ying Huang Yunzhao Yu Center for Molecular Science, institute of chemistry, {2. {3. of Sciences, beijing 100080, china chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

Trimethylsilylated silica was synthesized. through hydrolytic condensation of tetraethoxysilane followed by trimethylsilylation. Rheological properties of the silicone resin with trimethylsilylated silica as modifier were studied. It turned out that the particle size of silica was important to the rheological behavior of the modified resin. Trimethylsilylated silica of medium particle size shows the strongest tendency of forming physical network in the resin.

关键词： silica trimethylsilylation rheology modifier silicone resins

Physical mechanisms of plant roots affecting weathering and leaching of loess soil

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Science china Earth Sciences 2006年第9期49卷 1002-1008页

作者： LI Yong1,2. ZHANG Qingwen1,2. WAN Guojiang3. HUANG Ronggui3. PIAO Hechun3. BAI Lingyu2.& LI Lu2.1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, institute of Soil and Water Conservation, chinese {2. of Sciences, Yangling 712.00, china 2. institute of Agro-Environment and Sustainable Development, chinese {2. of Agricultural Sciences, {13. 100081, china 3. institute of Geochemistry, chinese {2. of Sciences, Guiyang 550002. china 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 China 2. institute of Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 China 3. institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Plant roots have potential impacts on soil mineral weathering and *** objective is to understand the physical mechanisms of plant roots affecting weathering andleaching of loess soil. Root densities were measured through the method of a large-size dug profile,and transport fluxes of soil elements were determined using an undisturbed monolith soilinfiltration device on the hilly and gully regions of the chinese Loess Plateau. The results showthat the improvement effects of soil environment by plant roots are mainly controlled by the densityand weight of the fibrous roots with the diameters less than 1 mm. Plant roots have the strongereffects on soil physical properties than chemical properties. The principal components analysis(PCA) indicates that soil physical properties by plant roots account for 56.7% of variations in soilenvironment whereas soil chemical properties and pH contribute about 2..2. of the soil *** roles of plant roots in controlling soil weathering and leaching increased in the followingorder: infiltration enhancement > increase of bio-active substance > stabilization of soilstructure. The effects of plant roots on soil mineral weathering and leaching can be quantifiedusing the multiple regression models with the high prediction accuracies developed in this study.

关键词： plant roots, soil weathering and leaching rates, soil environment field, principal components analysis (PCA), chinese Loess Plateau.