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Propagation of interplanetary shock excited ultra low frequency (ULF) waves in magnetosphere-ionosphere-atmosphere——Multi-spacecraft “Cluster” and ground-based magnetometer observations

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Science china(Technological sciences) 2010年第9期53卷 2528-2534页

作者： WANG ChengRui1,2.ZONG QiuGang1,3 & WANG YongFu1 1 institute of Space Physics and Applied Technology,Peking University,beijing 100871,{2. 2.Sate key laboratory of Space Weather,chinese academy of sciences,beijing 100190,{2. 3 Center for Atmospheric Research,600 Suffolk Street,University of Massachusetts Lowell,MA 01854,USA institute of Space Physics and Applied Technology Peking University Beijing China Sate key laboratory of Space Weather Chinese Academy of Sciences Beijing China Center for Atmospheric Research University of Massachusetts Lowell USA

The ultra low frequency (ULF) wave in magnetosphere can act as an important means for solar wind energy inward *** paper quantitatively analyzes the propagation process of the ULF wave triggered by the interplanetary shock propagating from inner magnetosphere equatorial plane along magnetic field lines to the top of the ionosphere and below ionosphere propagating process and establishes a relatively complete magnetosphere-ionosphere-atmosphere propagation model which can be used to study the relationship between the amplitude of the ULF waves triggered by the interplanetary shock wave in magnetospheric space and the magnetic effect caused by the ULF *** a comparison with recent observations,we found that: in the event during November 7,2.04 that an interplanetary shock wave interacted with the magnetosphere,Cluster satellites observed that electric field fluctuations and the band-pass filtered result of ground stations meridional component had similar *** with the geomagnetic measurement near the footprints,we found that the electric field disturbance in the magnetosphere spread along the ground magnetic field lines in the form of the ULF waves and changed into geomagnetic *** result reveals that the ULF wave is in contact with the ground geomagnetic *** ULF waves couple with ionized components in ionosphere and spread to the ground in the form of electromagnetic *** this research,we believe that the magnetosphere,ionosphere and ground magnetic effects caused by interplanetary shock wave are the same physical phenomena responding in different *** on the overall consideration of entire electromagnetic response to the interplanetary shock wave,we found that the correlation between CLUSTER multi-satellite observation and geomagnetic station observation is due to the ULF wave propagated in magnetosphere-ionosphere-atmosphere system,and we quantitatively interpreted this response process

关键词： ultra low frequency (ULF) wave magnetic storm ionosphere IRI model interplanetary shock

The excitation energy transfer between β-Car and Chla molecules in PS Ⅱ core antenna complexes CP43 and CP47

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chinese Science Bulletin 2000年第17期45卷 1579-1583页

作者： SHAN Jixiu, WANG Jushuo, LI Liangbi,ZHAO Nanming & KUANG Tingyun1. laboratory of Photosynthesis Basic Research, institute of Botany,{2., beijing 100093, china 2. Department of Biological sciences and Biotechnology, State key laboratory of Biomembrane and Membrane Biotechnology, Tsinghua University, beijing 100084, chinaCorrespondence should be addressed to Kuang Tingyun laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of Sciences Beijing China Department of Biological sciences and Biotechnology State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing China

The excitation energy transfer efficiency between p-Car and Chla molecules in purified CP43 and CP47 was calculated by comparing absorption and fluorescence excitation after normalization at 550 nm, CP43 had an energy transfer efficiency of 2..1% while the CP47 had an energy transfer efficiency of 62.8%, proving that excitation energy was transferred between p-Car and Chla molecules in CP43 and CP47 at normal conditions. The excitation energy transfer between p-Car and Chla molecules in CP43 and CP47 may occur through the "Dexter" mechanism and the distance between these two kinds of pigments should be less than 1 nm. In addition, the results were also used to discuss the conformational relationship between p-Car and Chla molecules in CP43 and CP47.

关键词： CP43 CP47 β-Car Chla excitation energy transfer.

A particle-based method for granular flow simulation

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Science china(Information sciences) 2012年第5期55卷 1062-1072页

作者： CHANG YuanZhang 1,BAO Kai 2.3,ZHU Jian 1 & WU EnHua 1,2.1 Department of Computer and Information Science,University of Macau,Macao,china 2.State key {2. of Computer Science,institute of Software,chinese academy of sciences,beijing 100190,china 3 Division of Mathematical and Computer sciences & Engineering,KAUST,Thuwal,Saudi Arabia Department of Computer and Information Science University of Macau Macao China State key laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing China Division of Mathematical and Computer sciences & Engineering KAUST Thuwal Saudi Arabia

We present a new particle-based method for granular flow *** the method,a new elastic stress term,which is derived from a modified form of the Hooke's law,is included in the momentum governing equation to handle the friction of granular *** force is also added to simulate the dynamic friction for the purpose of smoothing the velocity field and further maintaining the simulation *** from the Lagrangian nature of the SPH method,large flow deformation can be well handled easily and *** addition,a signed distance field is also employed to enforce the solid boundary *** experimental results show that the proposed method is effective and efficient for handling the flow of granular materials,and different kinds of granular behaviors can be well simulated by adjusting just one parameter.

关键词： granular materials sand smoothed particle hydrodynamics SPH Hooke’s law animation simu-lation

Effects of nitrogen ion implantation on Ca^(2.) concentration and membrane potential of pollen cell

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chinese Science Bulletin 2001年第20期46卷 1691-1693页

作者： HUANG Zhonglian, JING Yanping, ZHU Guoli, LU Ting, ZHOU Hongyu & REN Haiyun1. key laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, {2. Normal University, {2. 100875, china 2. key laboratory of Plant Physiology and Biochemistry of the Ministry of Agriculture, china Agriculture University, {2. 100094, china 3. Institution of Low energy Nuclear Physics, {2. Normal University, {2. 100875, china key laboratory of Cell Proliferation Regulation Biology of Min. of Educ. Beijing Normal University Beijing 100875 China

The effects of low energy nitrogen ion implantation on Ca2. concentration and membrane potential of illy (Mum davidii Duch) pollen cell have been studied. The results showed that the Ca2. concentration was increased when pollen grain was implanted by nitrogen ion with energy 100 keV and dose 1013 ions/cm2. However, the increase of Ca2. concentration was partly inhibited by the addition of Ca2. channel inhibitor depending on dose. And nitrogen ion implantation caused depolarization of pollen cell membrane potential. In other words, membrane potential was increased, but the effect decreased by adding Ca2. channel inhibitor. However, it was still significantly {2.er than the membrane potential of control cells. It was indicated that the depolarization of cell membrane potential opened the calcium channel on the membrane that caused the increasing of intracel-lular calcium concentration. This might be an earlier step of the effect of low energy nitrogen ion implantation on pollen germination.

关键词： nitrogen ion implantation lily pollen calcium concentration membrane potential.

EI NIO PHENOMENON AND EXTENDED ASSOCIATE PATTERN ANALYSIS

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Journal of Hydrodynamics 2004年第1期16卷 90-100页

作者： CUIMao-chang MOJun QIAOFang-li instituteofOceanology ChineseAcademyofSciences.Qingdao266071China／KeyLaboratoryofMarineScienceandNumericalmodelingTheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China. instituteofOceanology ChineseAcademyofSciences.Qingdao266071China keylaboratoryofMarineScienceandNumericalmodeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

To study the causes of El Nino Phenomenon the Extended Associate PatternAnalysis (EAPA) is set up with monthly sea surface wind stress and precipitation besides Sea LevelPressure (SLP) and Sea Surface Temperature (SST) in or over the Pacific and related seas since 1979in present paper. The results show that El Nino Phenomenon means a SST redistribution, coveringalmost the whole Pacific that needs a huge amount of energy provided by air-sea interaction in themost Pacific regions; It is the wester burst and wind convergence, coming from meddle latitudesdirectly, instead of Kelvin waves that produce the strong SST warm signal in Nino regions; Twonegative SLP anomalies in middle of the North and South Pacific, most likely produced by the averageair pressure decreasing effect of explosive cyclones through precipitation, and the positive SLPanomaly o-ver the Asia-Australia land bridge, coming mainly from the south hemisphere with a littleinfluence from the Asian continent, are the three major causes for El Nino onset, they work togetherto produce anomalous wind convergence in Nino regions and wester burst in middle of the North andSouth Pacific that result in a warm tongue and cold pincers gearing together; Basically, during itsearly stage the ocean is forced by the atmosphere, while during its late stage the atmosphere isforced by the ocean.

关键词： extended associate pattern analysis (EAPA) El nino phenomenon

TRANSIENT EFFECT OF A BOGER FLUID FLOWING AROUND A CONFINED CYLINDER

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chinese Journal of Polymer Science 2001年第4期19卷 377-384页

作者： Xian-feng Li Huai-tian Bu De-lu Zhao State key laboratory of Polymer Physics and Chemistry Center for Molecular Science,{2. of Chemistry, chinese academy of sciences, beijing 100080, china 中科院化学所高分子物理与化学国家重点实验室北京

This paper is concerned with the numerical simulation of the transient effect of an inertialess Boger flow past a confined circular cylinder and the comparison of predictions with particle image velocimetry (PIV) measurements given by Shiang et al.. Dynamic simulation based on the Oldroyd-B constitutive model was carried out using a Lagrangian-Eulerian algorithm. The evolution of velocity field was obtained for the flow at two Deborah (De) numbers, i.e. De = 1.2.and 3.0. At low De, the flow reached steady state rapidly, and showed a symmetric flow regime. However, at high De, the time required to reach steady flow behind the cylinder increased significantly, and the distribution of the velocity field appears to be asymmetric with respect to the stagnation line. Fairly good agreement between the numerical results and the experimental observations is reported. It can be concluded that both the experimental measurements and the present simulations indicate that the elasticity of the polymeric flow strongly affect the flow regime of viscoelastic flow around a confined cylinder.

关键词： transient effect flow around a cylinder Lagrangian-Eulerian algorithm Oldroyd-B model

Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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Science china Chemistry 2005年第5期48卷 424-430页

作者： LI Di1, SUN Chunyan1, HUANG Yunjie1, LI Jinghong1,2.& CHEN Shaowei3 1. State key laboratory of Electroanalytical Chemistry, Changchun {2. of Applied Chemistry, chinese academy of sciences, Changchun 13002., china 2. Department of Chemistry, Tsinghua University, beijing 100084, china 3. Department of Chemistry, University of California, Santa Cruz, Santa Cruz, CA 95064, USA State key laboratory of Electroanalytical Chemistry Changchun {2. of Applied Chemistry Chinese Academy of Sciences Changchun China Department of Chemistry Tsinghua University Beijing China Department of Chemistry University of California Santa Cruz Santa Cruz USA

Electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPCs) as elec-tron-transfer mediators. 3-Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPCs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPCs act as diffusing elec-tron-mediators and electron transfers to and from the MPCs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPCs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

Characteristics of low-frequency oscillations in course of SCS summer monsoon onset

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Acta Oceanologica Sinica 2000年第3期19卷 65-72页

作者：毛江玉谢安宋焱云叶谦 institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Some of the low-frequency oscillation (LFO) characteristics of summer moan onset over the South china Sea (SCS) are examined based on NCEP/NCAR reanalysis data and OLR from NOAA in the period of 1979-1996. It is found that the SCS summer monsoon is characterized by predominance of low-frequency activities with significant interannual variability closely related with onset time. The LFOs over the SCS strengthen after onset. Composite analyses for LFO components of OLR and kinetic energy indicate that the eastward propagation of LFO over the equatorial Indian Ocean and LFO coming from the western Pacific strongly affect the physical processes responsible for the SCS summer monsoon onset. The SCS is the place where the Indian Ocean LFO links with low-frequency activities over the western pacific during summer monsoon onset.

关键词： Low -frequency oscillation the South china Sea summer moan onset

XMM-Newton observation of the eclipsing binary Algol

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Research in astronomy and astrophysics 2011年第4期11卷 457-470页

作者： Xue-Juan Yang Fang-Jun Lu Bemd Aschenbach Li Chen Faculty of Materials Optoelectronics and Physics Xiangtan University Xiangtan 411105China particle astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Max-Planck-Institut fur Extraterrestrische Physik 85741 Garching Germany Department of astronomy Beijing Normal University Beijing 100875 China

We present an XMM-Newton observation of the eclipsing binary Algol which contains an X-ray dark B8V primary and an X-ray bright K2.V secondary. The observation covered the optical secondary eclipse and captured an X-ray flare that was eclipsed by the B star. The XMM-Newton European Photon Imaging Camera and Reflection Grating Spectrometer spectra of Algol in its quiescent state are described by a two-temperature plasma model. The cool component has a temperature around 6.4× 106 K while that of the hot component ranges from 2.to 4.0× 107 K. Coronal abundances of C, N, O, Ne, Mg, Si and Fe were obtained for each component for both the quiescent and the flare phases, generally with upper limits for S and Ar, and upper limits for C, N, and O from the hot component. F-tests show that the abundances do not need to be different between the cool and the hot component and between the quiescent and the flare phase with the exception of Fe. Although the Fe abundance of the cool component remains constant at -0.14, the hot component shows an Fe abundance of -0.2., which increases to -0.44 during the flare. This increase is expected from the chromospheric evaporation model. The absorbing column density NH of the quiescent emission is 2.5 - 102. cm-2. while that of the flare-only emission is significantly lower and consistent with the column density of the interstellar medium. This observation substantiates earlier suggestions of the presence of X-ray absorbing material in the Algol system.

关键词： stars abundance -- star binaries eclipsing -- stars flare -- stars indi-vidual Algol