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Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

Science china Earth Sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3,5, SUN Junying4,5, Paul A. Mayewski2 & QIN Dahe5 1. National Climate Center, china Meteorological administration, beijing 100081, china 2. Climate Change institute, University of Maine, Orono, ME 04469, USA 3. institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, china 4. Chinese Academy of Meteorological Sciences, beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering Research institute, Chinese Academy of Sciences, Lanzhou 730000, china 1. National Climate Center China Meteorological Administration 100081 Beijing China 2. Climate Change institute University of Maine 04469 Orono ME USA 3. institute of Tibetan Plateau Research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. Chinese Academy of Meteorological Sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

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Geochemistry of trace elements and Sr-Nd isotopes of foraminifera shell from the Okinawa Trough

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Acta Oceanologica Sinica 2001年第1期20卷 95-103页

作者： Meng Xianwei 1,2 ,Du Dewen 1,2 ,cheng Zhenbo 11 .FirstinstituteofOceanography ,StateOceanicadministration ,Qingdao 2 6 6 0 6 1,china2 .KeyLaboratoryofMarineScienceandNumericalModeling ,StateOceanicadministration ,Qingdao 2 6 6 0 6 1,china First institute of Oceanography State Oceanic Administration Qingdao 266061 China Key Lab. Mar. Sci. Numer. Modeling State Oceanic Administration Qingdao 266061 China

Trace elemental associations and Sr-Nd isotopic compositions are of important to recognition of biogenic material from mixed marine sediments. The foraminifera shell from the Okinawa Trough strongly enriches Sr,P,Mn and Ba, enriches Li,U,Th,Sc,Co,Cu,Pb,Zn,Cr,Rb,Y,Sb and light rare earth elements,slightly enriches V,Ga,Zr,Nb,Cd and middle rare earth elements,is short of Mo,In,Sn,Cs,Hf,Ta,W,Ti,Bi and heavy rare earth elements. The mechanism of elemental enrichment in forminifera is the concentrations of trace elements in sea water and selective absorption of trace elements during foraminifera living, as well as the geochemical affinity between major elements and trace *** REE (rare earth elements)partition pattern of foraminifera shell of the Okinawa Trough shows enrichment of middle rare earth elements with slightly negative Ce anomaly,which are different from those of foraminifera of the Pacific *** Sr,Nd isotopic ratios of the Okinawa Trough foraminifera are 0 709 769 and 0 512 162,respectively, which are different not only from those of oceanic water, but also from those of river water of china's Mainland, the former is slightly higher than those of oceanic water,but much lower than those of river water;the latter is slightly lower than those of oceanic water,but higher than those of river water,demonstrating that the Okinawa Trough sea water has been influenced by river water of china's Mainland.

关键词： Foraminifera shell trace element Sr-Nd isotopes

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Elastic wave propagation in inhomogeneous anisotropic media

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Acta Seismologica Sinica(English Edition) 1998年第6期11卷 3-15页

作者： XIU cheng WEI 1) MIN YU DONG 1) YUN YAI CHEN 2) 1) Geoscience Department, University of Petroleum, beijing 102200, china 2) institute of Geophysics, china Seismological Bureau, beijing 100081, china 1. Geoscience Department University of Petroleum 102200 Beijing China 2. institute of Geophysics China Seismological Bureau 100081 Beijing China

Plane wave decomposition is a convenient and effective method in the study of wave field. Various complex wave fields can be obtained by using plane wave composition. In this paper, the method of plane wave is used to study elastic wave propagation in inhomogeneous and anisotropic media. The f k transformation is applied to time space domain wave equation in inhomogeneous anisotropic media. As a result, the frequency wave number domain wave equation (Christoffel equation) can be obtained. Using the relation between elastic parameters or its spatial derivatives and Christoffel matrix elements, a method for solving the Christoffel matrix in inhomogeneous anisotropic media is formulated and applied to inhomogeneous TIV as well as inhomogeneous EDA media. The results obtained show that directional derivative of wave amplitude in continuum is negative, so amplitude is reduced, when propagating direction directs to velocity increasing direction; and directional derivative of wave amplitude is positive that means amplitude enhanced when propagating direction directs to velocity decreasing direction. Thus, wave amplitude depends on propagation direction (even in isotropic medium), but does not always attenuate. The conclusion that in continuum wave amplitude attenuates does not apply to all propagation direction.

关键词： inhomogeneous anisotropy continuum Christoffel equation

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The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2,4, ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3 1. State Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china 2. Department of Atmospheric Sciences, Yunnan University, Kunming 650091, china 3. china Meteorological administration Training Centre, beijing 100081, china 4. Graduate School of Chinese Academy of Sciences, beijing 10003., china State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric Sciences Yunnan University Kunming 650091 China Graduate School of Chinese Academy of Sciences Beijing 100039 China china Meteorological administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for Environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South china Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2nd pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

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Sporopollen analysis of Core B10 in the southern Yellow Sea and the reflected characteristics of climate changes

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Chinese Science Bulletin 2003年第B06期48卷 42-48页

作者： FU Mingzuo~(1,2,3), LI Zhen~1, XU Xiaowei~1 & SHl Xuefa~1 1. Key Laboratory of Marine Sedimentology and Environmental geology, First institute of Oceanography. State Oceanic administration, Qingdao 266061. china 2. institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071. china 3. Graduate School, Chinese Academy of Sciences, beijing 10003.. china 1. Key Laboratory of Marine Sedimentology and Environmental geology First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B10 in the southern Yellow Sea. Based on the results along with ^14C datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1) the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2) eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3) the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4) the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳14年代测定底基压型数据更新世沉积环境大西洋

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Sandy desertification trend in western Northeast china Plain in the past 10 years

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Journal of Geographical Sciences 2001年第2期11卷 179-186页

作者： LI Bao-lin~1,2, ZHOU cheng-hu~1 (1. LREIS, institute of Geographic Sciences and Natural Resources Research, CAS, beijing 100101, china 2. institute of Remote Sensing Application, CAS, beijing 100101, china) institute of Remote Sensing Application CAS LREIS Institute of Geographic Sciences and Natural Resources Research CAS LREIS Institute of Geographic Sciences and Natural Resources Research CAS

The west sandy land of the Northeast china Plain is located in the eastern huge sandy belt of mid-latitude in Eurasia and the eastern fringe of desertified land with best bio-climatic conditions in china. With rapid economic development, the deterioration of eco-environment has occurred and the desertification becomes very obvious. The first part of this paper studies the regional differences of landscape patterns and explores the regional differences of desertification. The second part aims to reveal the dynamics of desertification in the 1990s by using NOAA/AVHRR data and thematic data in GIS database. This work lays a scientific basis for the rehabilitation and development of the sandy lands.

关键词： west sandy land in Northeast china Plain landscape pattern regional difference remote sensing monitoring dynamic change

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A systematic investigation of high harmonic generation using mid-infrared driving laser pulses

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1054-1059页

作者： YAO JinPing 1,2 ,XIONG Hui 1 ,XU Han 1 ,FU YuXi 1,2 ,ZENG Bin 1,2 ,CHU Wei 1,2 ,cheng Ya 1 ,XU ZhiZhan 1 ,LIU XiaoJun 3 & CHEN Jing 4,5 1 State Key Laboratory of High Field Laser Physics,Shanghai institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,china 2 Graduate University of Chinese Academy of Sciences,beijing 100049,china 3 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan institute of Physics and Mathematics,Chinese Academy of Sciences,Wuhan 430071,china 4 institute of Applied Physics and Computational Mathematics,beijing 100088,china 5 Center for Applied Physics and Technology,Peking University,beijing 100084,china 1. State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China4. Institute of Applied Physics and Computational Mathematics Beijing 100088 China5. Center for Applied Physics and Technology Peking University Beijing 100084 China

We report on a systematic investigation of the influences of gas pressure,focal position and focusing geometry on high harmonic generation by use of mid-infrared femtosecond laser pulses. We also discuss the spatial characteristics of harmonics under different focusing conditions. By optimizing the parameters,we experimentally observed the generation of 1 kHz,low divergence coherent X-ray beams in the water-window region.

关键词： mid-infrared laser pulses high harmonic generation water window

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Research on the Historical Data of the 1585 A. D. South Chaoxian earthquake and Its Seismogenic Structure

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earthquake Research Advances 2010年第1期24卷 106-116页

作者： Zhai Hongtao1) ,Deng Zhihui2) ,Zhou Bengang2) ,Li Guang1) ,and Zheng Yingpin1) 1) earthquake administration of Anhui Province,Hefei 230031,china 2) institute of geology,china earthquake administration,beijing 100029,china earthquake administration of Anhui Province Hefei 230031 China institute of geology China Earthquake Administration Beijing 100029 China

In 1585,a MS5 3/4 earthquake occurred in the south of Chaoxian county,Anhui Province. The parameters of this earthquake were reported differently in various versions of earthquake catalogues. According to detailed textual research on the historic records of this earthquake,the epicenter location of the earthquake was further confirmed by means of seismo-geological field investigations in the Chaohu-Tongling region along the western Yangtze River valleys. Shallow seismic prospecting and drilling methods were applied in studying the buried fault. The possibility of the existence of seismogenic faults and fault activity in the western Yangtze River area were analyzed in depth,and the causative tectonic background of the 1585 MS5 3/4 south Chaoxian earthquake was studied. The results of this study indicate that the Yanjiaqiao-Fengshahu fault,which was active in the early to mid-Pleistocene,is possibly the causative structure of this earthquake. To identifying the seismogenic structure of the 1585 south Chaoxian earthquake will help gain more knowledge about the tectonic background of moderate and small earthquake activity in Eastern china.

关键词： Historical earthquake verification Seismogenic structure Chaoxian,Anhui

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Interfacial behaviors of PMMA-PEO block copolymers at the air/water interface

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Science china Chemistry 2005年第6期48卷 567-573页

作者： cheng Caixia1, JIAO Tifeng2, TANG Rupei1, LIU Minghua2 & XI Fu1 1. State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Materials, institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 2. CAS Key Laboratory of Colloid and Interface Science, institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 1. State Key Laboratory of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 2. CAS Key Laboratory of Colloid and Interface Science Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China

Diblock copolymer of PMMA291-b-PEO114 and triblock copolymer of PMMA120-b- PEO227-b-PMMA120 were synthesized and their interfacial properties at the air-water interface were investigated, where both blocks of polyethylene oxide (PEO) and poly(methyl methacrylate) (PMMA) are surface active but the former is soluble in water while the latter is not. Both the block copolymers could form monolayers with two obvious transition regions. The first transition point is around 10 mN/m, which could be assigned to the pancake-brush change of the PEO chains. The other is around 18 mN/m, which could be ascribed to the condensed packing of PMMA. The surface morphological changes during the compression of the Langmuir monolayers are inves-tigated by using the AFM and SEM methods for the films deposited at different surface pressure or molecular areas. At a lower surface pressure, a typical morphology of PEO-con- taining lipopolymers is observed. Upon compression, sphere-dominant morphologies were observed. While the diblock copolymer is easy to folding, the triblock copolymer is in favor of formation of circular domains through vesiculation.

关键词： PMMA-PEO, block copolymers, monolayer, Langmuir-Blodgett films, AFM.

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Optimizing the design of in situ sediment oxygen demand measurement chambers

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International Journal of Sediment Research 2011年第2期26卷 222-229页

作者： HE Yun and LIU cheng 1 Senior Engineer,Dr.,china institute of Water Resources and Hydropower Research,beijing 10003.,china, 2 Prof.,Dr.,International Research and Training Center on Erosion and Sedimentation,beijing 100048,china [a]Senior Engineer Dr. China Institute of Water Resources and Hydropower Research Beijing 100038 China [b]Prof. Dr. International Research and Training Center on Erosion and Sedimentation Beijing 100048 China

Sediment Oxygen Demand(SOD) is a key parameter for water quality analysis and for water quality modeling in rivers,lakes,estuaries and *** SOD can be measured both in the laboratory and in ***,the in situ technique appears to be the better approach for measuring SOD,as it likely to provide more representative and accurate *** order to optimize the design of in situ SOD measurement chambers,the three-dimensional flow fields in cylindrical SOD measurement chambers, commonly used for in situ measurements,have been numerically simulated by using the RNG-based k-s double equation turbulence *** chambers with three different inflow pipe configurations were *** results show that chamberⅢpresents distinct advantages over the other designs for in situ SOD measurement,because good flow mixing can be achieved and bottom sediment suspension can be avoided in the *** numerical simulation results were validated by comparison with existing results derived from laboratory *** SOD measurement chamber designed to reflect the results of the numerical simulations was successfully tested for in situ SOD measurements in both fresh and saline waters.

关键词： Sediment Oxygen Demand(SOD) Renormalization group(RNG) Velocity field In situ measurement Field tests

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