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Uppermost mantle structure of the North china Craton:Constraints from interstation Pn travel time difference tomography

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Uppermost mantle structure of the North China Craton:Constra...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： LI ZhiWei~(1,2),HAO TianYao~(1*) & XU Ya~1 ~1Key Laboratory of Petroleum Resources Research,Institute of Geology and Geophysics,chinese academy of sciences,Beijing 100029,{3. ~2Key Laboratory of Dynamical Geodesy,Institute of Geodesy and Geophysics,chinese academy of sciences,Wuhan 43.077,{3.

The uppermost mantle is the key area for exchange of heat flux and material convection between the crust and lithospheric mantle. Spatial variations of lithospheric thinning and dynamic processes in the North china Craton could inevitably induce the velocity heterogeneity in the uppermost *** this study,we used Pn arrivals from permanent seismic stations in North china and surrounding regions to construct a tomographic image of the North china *** tomographic method with Pn travel time difference data were used to study the velocity variations in the uppermost *** velocities in the uppermost mantle varied significantly in the Eastern,Central and Western blocks of the North china *** suggests that the lithosphere beneath different blocks of the North china Craton have experienced distinct tectonic evolutions and dynamic processes since the Paleozoic. The current uppermost mantle has been imprinted by these tectonic and dynamic *** Pn velocities are prominent beneath the Bohai Bay Basin in the Eastern Block of the North china Craton,suggesting residuals of the Archean lithospheric *** the Tanlu Fault Zone and Bohai Sea,slow Pn velocities are present in the uppermost mantle,which can be attributed to significant lithospheric thinning and asthenospheric *** newly formed lithospheric mantle beneath Yanshan Mountain may be the dominant reason for the existence of slow Pn velocities in this ***,the ancient lower crust and lithospheric mantle already have been *** the Central Block,significant slow Pn velocities are present in Taihangshan Mountain,which also extends northward to the Yinchuan-Hetao Rift on the northern margin of the Ordos Block and Yinshan *** characteristic probably is a result of hot asthenospheric upwelling along the active tectonic boundary on the margin of the Western *** protracted thermal erosion and underplating of hot asthenospheric upwelling may induce

关键词： North china Craton Lithospheric thinning Uppermost mantle Pn travel time difference Cratonic destruction

New evidence Ⅱ for MDD model of thermal evolution history of Gangdese batholith

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chinese Science Bulletin 1999年第8期44卷 736-739页

作者： CHEN Wenji , LI Qi , HAD Jie , ZHOU Xinhua and SUN Min Institute of Geology, china Seismological Bureau, Beijing 100029, china Institute of Geology , chinese {3. of sciences , Beijing 100029, china Department of Karth sciences , Hong Kong university , Hong Kong , china

The cooling curves are obtained using specific 40Ar/3.Ar stage heating procedure and MDD modeling. In addition to the results of dating hornblende (K-Ar) and apatite (FT), the widespread existence of rapid cooling events has further been confirmed. A new knowledge of the starting time of Gangdese overthrust faulting in the east of Zedang, which was earlier in south and later in north is acquired.

关键词： Tibet thermal history multiple diffusion domain model.

Temperature dependence of circular DNA topological states and a solution to a single molecular experiment problem

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Temperature dependence of circular DNA topological states an...

第十一次中国生物物理学术大会暨第九届全国会员代表大会

作者： Yanhui Liu1,Hu Chen 2,Lin Hu 1,Zhong-Can Ou-Yang 3.and Jie Yan 2 1.Guizhou university,College of Science,Guiyang,550025 2.National university of Singapore,Department of Physics,Science Drive 3. Singapore,117542 3.The Institute of Theoretical Physics,chinese {3. of sciences,Beijing,china, 100080

＜正＞Circular double stranded DNA has different topological states which are defined by their linking *** distribution of linking numbers can be obtained by closing a

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铁代谢蛋白在肾脏的表达与功能

生物化学与生物物理进展 2011年第2期38卷 113-118页

作者：蔺艳钱忠明柯亚香港理工大学应用生物化学系香港中文大学医学院生物医学学院

最近的研究证实,肾小管细胞具有能力表达包括转铁蛋白受体1(transferrin receptor-1,TfR1)、二价金属离子转运蛋白1(divalent metal transporter-1,DMT1)、膜铁转运蛋白1(ferroportin-1,FPN1)、铁调节蛋白(iron regulatory protein,IRP)和铁调素(hepcidin,Hepc)在内的几乎所有铁代谢蛋白.这些蛋白质的存在以及相关研究显示肾脏可能具有排出多余铁的功能,因此对体铁平衡起有十分重要的作用.

关键词：肾小管铁代谢蛋白排铁铁平衡

Discovery of a high confidence soft lag from an X-ray flare of Markarian 421

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 224-227页

作者： ZHANG YouHong1,HOU ZhengTian2,SHAO Li3.& ZHANG Peng1 1 Department of Physics and Tsinghua Center for Astrophysics(THCA),Tsinghua university,Beijing 100084,china 2 Group of Mathematics and Physics,Shangqiu Medical College,Shangqiu 476100,china 3.Max-Planck-Institut für extraterrestrische Physik,Postfach 13.2,Garching 85741,Germany 1. Department of Physics and Tsinghua Center for Astrophysics (THCA) Tsinghua University Beijing 100084 China 2. Group of Mathematics and Physics Shangqiu Medical College Shangqiu 476100 China 3. Max-Planck-Institut für extraterrestrische Physik Postfach 1312 Garching 85741 Germany

We present the X-ray variability properties of the X-ray and TeV bright blazar Mrk 421 with a-60 ks long XMM-Newton observation performed on November 9-10,*** source experienced a pronounced flare,of which the inter-band time lags were determined with a very high confidence *** soft(0.6-0.8 keV) X-ray variations lagged the hard(4-10 keV) ones by 1.09+0.11-0.12 ks,and the soft lag increases with increasing difference in the photon *** energy-dependent soft lags can be well fitted with the difference of the energy-dependent cooling timescales of the relativistic electron distribution responsible for the observed X-ray emission,which constrains the magnetic field strength and Doppler factor of the emitting region to be Bδ 1/3.1.78 Gauss.

关键词： BL Lacertae objects:individual:Mrk-421 galaxies:active radiation mechanisms:non-thermal X-rays:galaxies

The impacts of '05.6' extreme flood event on riverine carbon fluxes in Xijiang River

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The impacts of '05.6' extreme flood event on riverine carbon...

中国科学院地质与地球物理研究所2007学术年会

作者： SUN HuiGuo~(1+),HAN JingTai~1,ZHANG ShuRong~2 & LU XiXi~2 1 Institute of Geology and Geophysics,chinese academy of sciences,Beijing 100029,{3. 2 Department of Geography,National university of Singapore,117570,Singapore

An extreme flood event with a frequency of nearly 200 year occurred in June of 2005 in the Xijiang River, the main trunk stream of the Zhujiang *** were systematically collected during the flood event,and water quality parameters,including total suspended sediment(TSS),dissolved inorganic carbon(DIC),dissolved organic carbon(DOC),and particulate organic carbon(POC) were analyzed, and riverine carbon concentrations associated with its changing pattern through the flood process were *** parameters reflect the changes in basin surface flow and subsurface flow during the *** flood event influenced annual flux estimations of POC,DOC,and DIC to great extents. Based on carbon flux estimations for the year 2005 and the flood event(June 21-28) in the Xijiang River,it was found that DIC,DOC,and POC fluxes during‘05.6’ flood event are 1.52×***.a, 0.24×10 ***,and 0.54×10 ***.a,and account for 14.87%,24.75%and 44.89%of the annual fluxes in 2005,*** results suggested that carbon exports during extreme flood events had great contributions to the total carbon fluxes and composition of various carbon components,being important for accurate estimates of annual carbon fluxes in rivers with frequent floods.

关键词： Xijiang River flood riverine carbon flux

Comparison of the Thermomagnetic and Thermal Effects duringNanocrystallization of Amorphous Fe_(76.5-x)Cu_1Nb_xSi_(13.5)B_9 Alloys

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Journal of Materials Science & Technology 1998年第4期14卷 323-326页

作者： B.Varga and Tak■cs(Dept. of Mechanical Engineering Technology Technical university of Budapest, H-1111 Budapest Bertalan L. utca 2., Hungary) A.Lovas and P.Kamasa(Research Institute for Solid State Physics, Hungarian academy of sciences, H-1525 Budapest, Dept. of Mechanical Engineering Technology Technical University of Budapest Bertalan L.utca 2 H-1111 Budapest Hungary Research Institute for Solid State Physics Hungarian Academy of Sciences P.O.Box 49 H-1525 Budapest Hungary State Key Lab. of RSA Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China Institute of Materials Science Hungarian Academy of Science P.O.Box 49 H-1525 Budapest Hungary

The results of thermomagnetic (TM) and calorimetric (DSC) measurements have been compared in order to clarify some details of the mechanism of nanophase-formation from Finemet-type precursors with different Nb contents. It was found that the main features of the DSC thermograms (shape, relative separation and amplitude of the exothermic peaks characteristic for the precipitation of the Fe-(Si) solid solution and the transition metal borides) depend mainly on the composition of the precursor glass, and are only slightly affected by the heating rate between 20 and 80 K/min. The amplitude of the uprise of the magnetization in the TM curves (attributed to the precipitation of bcc-Fe(Si) and borides) decreases with increasing Nb-content. The Curietemperature of the precursor glasses. Tc(am1), the remainder amorphous phases, Tc(am2) and the bcc nanophase, Tc(n-Fe) are determined from the thermomagnetic curves. The shape of the TM curves is interpreted on the basis of the reactions describing the crystalIization of the hypo-eutectic Fe-B glasses.

关键词： Comparison of the Thermomagnetic and Thermal Effects duringNanocrystallization of Amorphous Fe B9 Alloys Cu x)Cu1NbxSi

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农业管理措施对土壤有机碳动态变化的影响

土壤通报 2004年第5期35卷 648-651页

作者：朱咏莉韩建刚吴金水中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室西北农林科技大学资源环境学院陕西杨凌712100

土壤碳固定问题已成为陆地生态系统碳循环研究的热点问题。土壤碳固定是缓解温室效应加剧的有效方法之一。土壤有机碳含量变化受土地利用方式和耕作措施的强烈影响。将自然土壤转变为耕作土壤会导致土壤碳库的迅速下降,使土壤损失有机碳... 详细信息

土壤碳固定问题已成为陆地生态系统碳循环研究的热点问题。土壤碳固定是缓解温室效应加剧的有效方法之一。土壤有机碳含量变化受土地利用方式和耕作措施的强烈影响。将自然土壤转变为耕作土壤会导致土壤碳库的迅速下降,使土壤损失有机碳4.1-5.0×1013.g之间。采用新的农业措施会使碳损失量的60-70%重新被固定。这些措施有保护性耕作(少耕或免耕)、合理施用肥料、覆盖作物、应用深根且富含木质素的作物等。土壤除了固定有机碳外,干旱和半干旱地区土壤还具有固定无机碳的巨大潜力。文章还简要介绍了评价土壤有机碳的两种方法,并对今后的工作提出了几点建议。

关键词：管理措施碳固定农业土壤

Study on the Eco-economic Regionalization Using GIS in Loess Plateau of Dingxi City, Gansu Province of china

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Study on the Eco-economic Regionalization Using GIS in Loess...

中国农村建筑与环境技术创新学术研讨会

作者： Yu Li, Lili Wang, Xiaoming Qi ,Lin Xu, Quan Zhang Institute of Geographical sciences and Natural Resources Research chinese academy of sciences, Beijing 100101, china chinese Agriculture university

＜正＞Based on the land-use datum （at scale of 100,000） of the interpretation of Landsat Thematic Mapper image in 2000 and Land-use datum of detailed general survey, national geographic foundation data （1:250,000）, observation datum such as precipitation, average temperature, accumulated temperature, and datum of vegetation;social economic statistic datum such as population, rural social product value, industry structure, per capita grain crops yield, and rural industry product value in 168 towns and townships’ scale in Loess Plateau of Dingxi city, Gansu Province of china, by using geographic information systems （GIS） method, the study divided the case region into three level eco-economic regions and seven sub-level eco-economic regions. Finally, the author summed up 168 towns and townships to 12 function types according to their social economic development and respective characteristic of eco-economic region. It will benefit the policies making of sustainable development in this region in the future.

关键词： Loess Plateau of Dingxi city eco-economic regionalization