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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 {2.,beijing 100012.china.2.graduate school of chinese academy of {2.,beijing 100049,china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate school of {2. academy of sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 1137 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 10^12.⊙. 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 39%.

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

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of {2., beijing 100049 2.graduate school of chinese academy of {2., beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate school of {2. academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

Valuations on arithmetic surfaces

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Science china.Mathematics 2009年第1期52卷 66-76页

作者： XU Ning Department of Mathematics, graduate school of {2. academy of sciences, beijing 100049, china Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing China

In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ? p,G is algebraically closed. Based on this the author obtains the complete classification of valuations on arithmetic surfaces. Furthermore, for any m ? p,G n ∈ ?, let V m,n be an ∝-vector space of dimension n - m + 1, whose coordinates are indexed from m to n. We generalize the definition of ? p,G , where p is a prime and G ? V m,n is an additive subgroup containing 1. We also conclude that ? p,G is a field if m ? 0 ? n.

关键词： valuation height rank totally ordered group big field transcendental number 14J10

Structure of augmentation quotients of finite homocyclic abelian groups

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Science china.Mathematics 2007年第9期50卷 1280-1288页

作者： Guo-ping TANG school of Mathematical sciences,{2. University of chinese academy of sciences,beijing 100049,china school of Mathematical sciences Graduate University of Chinese Academy of Sciences Beijing China

Let G be a finite abelian group and its Sylow p-subgroup a direct product of copies of a cyclic group of order p r , i.e., a finite homocyclic abelian group. Let Δ n (G) denote the n-th power of the augmentation ideal Δ(G) of the integral group ring ?G. The paper gives an explicit structure of the consecutive quotient group Q n (G) = Δ n (G)/Δ n+1(G) for any natural number n and as a consequence settles a problem of Karpilovsky for this particular class of finite abelian groups.

关键词： integral group ring augmentation ideal consecutive quotient of augmentation ideal 16S34 2.C05

A Test on Different Types of the Time Curve of Hardness Ratio of Gamma-Ray Bursts based on the Curvature Effect

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chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 451-464页

作者： Lan-Wei Jia National Astronomical Observatories/Yunnan Observatory,chinese academy of {2.,Kunming 650011,china.graduate school of chinese academy of {2.,beijing 100049,china National Astronomical Observatories/ Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China graduate school of {2. academy of sciences Beijing 100049 China

We analyzed a sample of 66 gamma-ray bursts （GRBs） and statistically confirmed the prediction on the time curve of the hardness ratio of GRBs made by Qin et al. based on the curvature effect. In their analysis, GRB pulses are divided into three types according to the shape of their raw hardness ratio （RHR） time curves, defined as to include the background counts to the signal counts, so as to make use of counts within small time intervals. Of the three types, very hard sources exhibit a perfect pulse-like profile （type 1）, hard bursts possess a pulse-like profile with a dip in the decay phase （type 2., and soft bursts show no pulse-like profile but have only a dipped profile （type 3）. In terms of the conventional hardness ratio, type 3 sources are indeed generally softer than those of type 1 and type 2. in agreement with the prediction. We found that the minimum value of RHR is sensitive in distinguishing the different types. We propose that GRB pulses can be classified according to the minimum value of RHR and that the different type sources may be connected with different strengths of the shock or/and the magnetic field.

关键词： gamma-rays burst -- gamma-rays observations - methods statistical

Applications of URANS on predicting unsteady turbulent separated flows

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Acta Mechanica Sinica 2009年第3期25卷 319-324页

作者： Jinglei Xu Huiyang Ma Department of Physics, graduate University of the chinese {2. of sciences, 100049 beijing, china Department of Physics Graduate University of the Chinese Academy of Sciences Beijing China

Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2. flow past a circular cylinder at Reynolds number 3,900 is numerically investigated by using the technique of unsteady RANS （URANS）. Some typical linear and nonlinear eddy viscosity turbulence models （LEVM and NLEVM） and a quadratic explicit algebraic stress model （EASM） are evaluated. Numerical results have shown that a high-performance cubic NLEVM, such as CLS, are superior to the others in simulating turbulent separated flows with unsteady vortex shedding.

关键词： URANS Nonlinear eddy viscosity turbulencemodel ,Separated flows Circular cylinder

Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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Science china.Physics,Mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG XiaoChao1,2. & WANG ShiJin1 1 Center for Space Science and Applied Research, chinese academy of {2., beijing 100190, china.2.graduate University of chinese academy of {2., beijing 100049, china Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China graduate University of chinese {2. of sciences Beijing China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2.04, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2.05 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2.srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 2.-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

Comparative study of pollination biology of two closely related alpine Primula species,namely Primula beesiana and *** (Primulaceae)

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Journal of Systematics and Evolution 2010年第2期48卷 109-117页

作者： 1,2.hi-Kun WU 1Chang-Qin ZHANG 1(Kunming Institute of Botany,chinese academy of {2.,Kunming 6502.4,china. 2.graduate school of chinese academy of {2.,beijing 100049,china. (Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate school of {2. academy of sciences Beijing 100049 China)

The comparative pollination biology of a population of Primula beesiana,a population of ***,and an overlapping population of these two species in Yulong Shan,Yunnan Province,china.was studied in 2.04 and *** results indicate that both *** and *** are typical heterostylous and obligate outcrossing species;the main pollinators of the two species were bees and *** the sites of all three populations,the main pollinating visitors of the two species showed preference for one of the two species,resulting in the ethological isolation of the two species by the *** ethological isolation contributes to the reproductive isolation of the two species,which supports the hypothesis that *** and *** are two distinct *** reproductive isolation of the two species (ethological isolation) is probably an important mechanism in maintaining species boundaries in the genus and has contributed to the species diversification of Primula in the *** addition,gene exchanges between *** and *** has occurred to some extent in the overlapping population,but whether natural hybridization has contributed to species diversification in Primula remains to be determined.

关键词： pollination biology Primula beesiana Primula bulleyana reproductive isolation

Novel Tumor-associated Antigen of Hepatocellular Carcinoma Defined by Monoclonal Antibody E4-65

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Acta Biochimica et Biophysica Sinica 2007年第5期39卷 359-365页

作者： Ke ZOU~(1,2., Jihang JU~(1,2., and Hong XIE~~(1*)1 Institute of Biochemist13, and Cell Biology, Shanghai Institutes for Biological sciences, chinese {2. of sciences, Shanghai 2.0031, china. 2.graduate school of the chinese {2. of sciences beijing 100049, china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China graduate school of the {2. academy of sciencesbeijing 100049 China

A monoclonal antibody, E4-65, produced by immunizing mice with SMMC-772. cells, a human hepatocellular carcinoma (HCC) cell line, was used to identify and characterize an unreported HCC-associated antigen. Indirect immunofluorescence studies showed that E4-65 antibody reacted with five out of eight HCC cell lines, but not with 10 non-HCC tumor cell lines or a normal liver cell line. Using immunohistochemical examination, E4-65 antigen was detected on the cell membranes and in the cytoplasm of human liver tumor tissues, but was not found in most other tumors, or normal adult or fetal tissues, except for a weakly positive reaction in tissues of the digestive system. Western blot analysis showed that E4-65 antibody bound to a 45 kDa protein in the human HCC cell line and tissue lysates. Enzyme treatment and lectin blotting did not detect the carbohydrate chain in E4-65 antigen. This HCC-associated protein represents a potentially useful target for diagnoses and immunotherapy of human HCC.

关键词： hepatocellular carcinoma immunohistochemistry monoclonal antibody neoplasm antigen