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A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

Science china(Technological sciences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2 & FENG Xueshang1,3.1. SIGMA Weather Group, Key laboratory of Space Weather, Center for Space Science and Applied Re-search, chinese academy of sciences, beijing 100080,{3. 2. Graduate School of the chinese academy of sciences, beijing 10003.,{3. 3. School of Geophysics and Geoinformation Systems,{3. University of Geosciences, beijing 100083.{3. 1. SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. School of Geophysics and Geoinformation Systems China University of Geosciences 100083 Beijing China

Using 80 CME-ICME events during 1997.1―2002.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2) The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3. The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 3.% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

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Analysis of tandem repeats in the genome of chinese shrimp Fenneropenaeus chinensis

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chinese Science Bulletin 2005年第14期50卷 1462-1469页

作者： KONG Jie1 & GAO Huan2,3.1. Key laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, chinese academy of Fishery {3., Qingdao 266071, china 2. institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 3. The Graduate School of the chinese academy of sciences, beijing 10003., china Key laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheris Research Institute Chinese Academy of Fishery Sciences Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China The Graduate School of the chinese academy of sciences Beijing China

Through random sequencing, we found a total of 884000 base-pairs (bp) of random genomic sequences in the genome of chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2159 tandem repeats were found, in which there were 1714 mi- crosatellites and 445 minisatellites, accounting for 79.4% and 20.6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2% of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.42%. In decreasing order, the 20 most abundant repeat sequence classes were as follows: AT (557), AC (471), AG (274), AAT (92), A (56), AAG (28), ATC (27), ATAG (27), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them.

关键词：虾遗传特性遗传基因 DNA

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6-Membered ring intermediates in polymerization of N-carboxyanhydride-L-α-arginine in H_2O

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Science china Chemistry 2009年第8期52卷 1220-1226页

作者： XIN Liang1,REN Jie1,XIANG JunFeng2,YAN Qin1,XIE Yi1,WANG KongJiang1,LAI PingAn3.& BAI YaDuo3.1 institute of Biophysics,chinese academy of {3.,beijing 100101,china 2 beijing national laboratory for Molecular {3.(BNLMS),Centre for Molecular {3.,institute of Chemistry,chinese academy of {3.,beijing 100080,china 3.beijing Entry-Exit Inspection and Quarantine,beijing 100026,china 1. institute of Biophysics Chinese Academy of Sciences Beijing 100101 China 2. beijing national laboratory for Molecular {3. (BNLMS) Centre for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 3. beijing Entry-Exit Inspection and Quarantine Beijing 100026 China

In polymerization of N-carboxyanhydride-L-α-arginine(L-Arg-NCA) in H2O,nucleophilic reaction of guanidine group with the carbonyl group of L-Arg-NCA leads to quick intramolecular rearrangement,yielding a 6-membered ring intermediate 1-amidino-3.amino-2-piperidone,which is either elongated by another L-Arg-NCA yielding arginyl-1-amidino-3.amino-2-piperidone or hydrolyzed to L-α-*** oligoarginines are formed mainly through hydrolysis of *** is a unique pathway in polymerization of L-Arg-NCA with regard to the usual pathway of elongations by reaction of N-carboxyanhydride-L-α-amino acid with L-α-amino acid or oligopeptides.

关键词： N-carboxyanhydride L-Arg-NCA intermediates L-α-arginine polymerization

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The Multifractal Analysis of the Occupation Measure of a Lévy Process

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Wuhan University Journal of Natural sciences 2000年第3期5卷 253-256页

作者： Hu Xiao\|yu institute of Applied Mathematics, chinese academy of sciences, beijing 100080,{3. chinese academy of sciences Institute of Applied Mathematics Beijing China (GRID:grid.9227.e) (ISNI:***)

We introduce the results on the multifractal structure of the occupation measures of a Brownian Motion, a stable process, a general subordinator and a stochastic process derived from random reordering of the Cantor se... 详细信息

关键词： occupation measure Levy process Brownian motion stable process subordinator

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RECOVERY OF AMORPHOUS POLY(ETHYLENE TEREPHTHALATE)FILM UNIAXIALLY DRAWN JUST BELOW THE GLASS TRANSITION TEMPERATURE

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chinese Journal of Polymer Science 2000年第1期18卷 69-75页

作者： Nan-jian Sun Juan Yang De-yan Shen Ren-yuan Qian institute of Chemistry, chinese academy of sciences, beijing 100080,{3. chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Isothermal recovery in the macroscopic length of homogeneously deformed specimens of amorphous poly(ethylene terephthalate) (PET) film sample uniaxially drawn at 69 degrees C to the draw ratios lambda(0) = 1.26-2.20 were studied at temperatures around the glass transition temperature (T-g = 73.degrees C). Experimental results indicate that the length recovery look place in two distinct steps: a fast first step (fast relaxation) followed by a slow second step (slow relaxation). The relaxation processes were accompanied by the reversion of trans-conformers (13.0 cm(-1)) to gauche, and the dichroic function of the 13.0 cm(-1) band characterizing the segmental orientation along the chain direction decreased to a very low value at the end of the fast relaxation. This fact led us to assign the fast relaxation as the segmental orientation while the slow relaxation as relaxation of the global chain orientation. It was found that the slow relaxation follows a single exponential function, with relaxation times strongly dependent on the temperature resembling the glass transition process. The fast relaxation does not follow a single exponential decay, presumably a distribution of relaxation times is involved.

关键词： poly(ethylene terephthalate) uniaxial drawing recovery orientation

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Low dipole moment large β electrooptic chromophores based on exocyclic double bond conjugated bridge

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chinese Science Bulletin 2001年第18期46卷 1517-1522页

作者： WANG Peng, LI Shaojun & YE ChengCenter for Molecular Science, Organic Solids laboratory, institute of Chemistry, chinese academy of sciences,{3., china Center for Molecular Science Organic Solids Laboratory Institute of Chemistry Chinese Academy of Sciences Beijing China

Novel low dipole moment (μ) and large first hyperpolarizability (β) electrooptic chromophores have been designed based on the special characteristic of reversed dipole moment in the excited state of exocyclic double bond (ECDB) conjugated bridge by the optimization of the substituted method, and their electronic and second-order nonlinear optical properties have been theoretically investigated by employing the AM1/FF and ZINDO/S-CI approaches. By extending the conjugation length and optimizing the donor/acceptor strength, the oscillator strength of the excited transition that contributes to the molecular nonlinearity can be further enhanced. The designed chromophores possess a larger figure of merit (FOM) than that of 4-N,N-dimethylamino-4’-nitrostilbene (DANS), and lower (5 D) ground state dipole *** low dipole moment (μ) and large first hyperpolarizability (β) electrooptic chromophores have been designed based on the special characteristic of reversed dipole moment in the excited state

关键词： AM1/FF ZINDO/S-CI molecular design dipole moment (μ) first hyperpolarizability (β) exocyclic double bond.

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Application of three-dimensional discrete element face-to-face contact model with fissure water pressure to stability analysis of landslide in Panluo iron mine

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Science china(Technological sciences) 2005年第z1期48卷 146-156页

作者： ZHANG Lei1,2, WEI Zuoan1, LIU Xiaoyu1 & LI Shihai1 1.institute of mechanics, chinese academy of sciences,{3., china 2.Graduate School, chinese academy of sciences, beijing 100060, china chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China

Three-dimensional discrete element face-to-face contact model with fissure water pressure is established in this paper and the model is used to simulate three-stage process of landslide under fissure water pressure in the opencast mine, according to the actual state of landslide in Panluo iron mine where landslide happened in 1990 and was fathered in 1999. The calculation results show that fissure water pressure on the sliding surface is the main reason causing landslide and the local soft interlayer weakens the stability of slope. If the discrete element method adopts the same assumption as the limit equilibrium method, the results of two methods are in good agreement; while if the assumption is not adopted in the discrete element method, the critical φ numerically calculated is less than the one calculated by use of the limit equilibrium method for the sameC. Thus, from an engineering point of view, the result from the discrete element model simulation is safer and has more widely application since the discrete element model takes into account the effect of rock mass structures.

关键词： face-to-facecontactmodel, fissure water pressure, three-dimensional discrete element method,landslide.

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Effects of gravity waves on the distributions of O_3.and OH in the mesopause region

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chinese Science Bulletin 2001年第15期46卷 1265-1268页

作者： XU Jiyao & MA Ruipinglaboratory for Space Weather, Center for Space Science and Applied Research, chinese academy of sciences, beijing 100080,{3. laboratory of Numeric Study of Heliospheric Physics, chinese academy of sciences, beijing 100080,{3. laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China laboratory of Numeric Study of Heliospheric Physics Chinese Academy of Sciences Beijing China

A dynamical-photochemical model of atmospheric gravity waves is used to study the influences of gravity waves on distributions of atmospheric minor species through transportation and photochemical reactions. We mainly study the effect of gravity waves on the distributions of atmospheric trace gases through the nonlinear photochemical reactions. O3.and OH are taken as examples in this note. The calculations indicate that the effect of gravity waves on the distributions of atmospheric trace gases is mainly through the nonlinear photochemical reactions in the mesopause region. The contribution of the nonlinear photochemical reaction caused by gravity waves can exceed the nonlinear transportation and the eddy diffusion.

关键词： gravity wave photochemical reaction coupling between photochemistry and dynamics.

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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 academy of sciences, Wuhan 43.077, china 2. Graduate School of the chinese academy of sciences, beijing 10003., china 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 20003., 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 200 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

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Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 national Astronomical Observatories,chinese academy of {3.,beijing 100012,china 2 Graduate School of chinese academy of sciences,beijing 100049,china national Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate School of chinese academy of sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 113. nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12L⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 3.%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

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