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Effects of various solar indices on accuracy of Earth’s thermospheric neutral density models

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1120-1128页

作者： WANG HongBo1,2 & ZHAO ChangYin1 1 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 2 graduate university of chinese academy of sciences, beijing 100049, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China graduate university of chinese academy of sciences Beijing 100049 China

Four kinds of solar indices F10.7, E10.7, S10, Mg10 and four thermospheric neutral density models, i.e., CIRA72, DTM94, NRLMSISE00 and JB2006, are discussed. The CHAMP accelerometer data are used to calculate thermospheric total mass density. Based on the comparison of the model densities with CHAMP observations, the effects of various indices on the model accuracy are detected. It is found that under quiet and moderate solar conditions (F10.7200) the error’s standard deviation using E10.7 increases quickly and causes the models’ accuracy to fall down. With regard to S10, Mg10, their effects under quiet solar conditions are inconspicuous. If under active solar conditions, they can reduce the model error’s standard deviation by 5%-10%, implying that S10, Mg10 make the model error more stable. The JB2006 model, which was constructed by multi-solar-index (F10.7, S10, Mg10), is compared with DTM94 and NRLMSISE00 based on single-solar-index. It is found that JB2006’s accuracy is better than DTM94’s, and is close to NRLMSISE00 under the quiet solar condition. During the solar burst occurring on October 26, 2003, JB2006 has been in best agreement with CHAMP observations. All in all, the new indices may improve thermospheric density models’ accuracy under some special conditions. Concretely, E10.7 may reduce the average error of models and S10, Mg10 may prevent the error’s divergence.

关键词： solar radiation index CHAMP accelerometer data neutrals density model

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3 , HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4 , ZHANG Shu 2 & ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, chinese academy of sciences, beijing 100012, china 2 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, beijing 100049, china 3 graduate university of the chinese academy of sciences, beijing 100049, china 4 Department of Physics, Nanjing Normal university, Nanjing 210011, china 1. Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Adlayer structure of TCNQ molecules on Cu(111): An in situ STM study

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chinese Science Bulletin 2001年第5期46卷 377-380页

作者： WAN Lijun & Kingo ItayaInstitute of Chemistry, chinese academy of sciences, beijing 100080, china Department of Applied Chemistry, graduate School of Engineering, Tohoku university, Sendai, Japan Institute of Chemistry Chinese Academy of Sciences Beijing China Department of Applied Chemistry Graduate School of Engineering Tohoku University Sendai Japan

In situ electrochemical scanning tunneling microscopy (STM) was employed to examine tetracyano-quinodimethane (TCNQ) layer adsorbed on Cu(lll) electrode surface in 0.1 mol/L HC1O4 solution. The TCNQ molecules are found to form highly-ordered long range ad-layer with a (4×4) symmetry. Each TCNQ molecule is adsorbed on Cu(111) surface in flat-lying orientation. The molecules are preferentially aligned with their long axes inthe [ 121 ] direction. A structural model is proposed for the adlayer.

关键词： TCNQ molecule electrochemical scanning tunneling microscopy Cu(111) adlayer structure.

A puzzle of the radio-quiet quasar PG 1407+265:Are optical and X-ray emissions produced from a relativistic jet?

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2,3 & BAI JinMing 1,2 1 National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,china 2 Key Laboratory for the Structure and Evolution of Celestial Objects,chinese academy of sciences,Kunming 650011,china 3 graduate university of chinese academy of sciences,beijing 100049,china 1. National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China2. Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

PG 1407+265 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+265,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+265

Periodicity of Retzius lines in fossil Pongo from South china

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chinese Science Bulletin 2012年第7期57卷 790-794页

作者： HU Rong1,2,3, ZHAO LingXia1,2 & WU XinZhi2 1 Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044, china 2 Laboratory of Human Evolution, Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044, china 3 graduate university of chinese academy of sciences, beijing 100049, china Laboratory of Human Evolution Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China

Periodicity of Retzius lines is a key factor in dental development. In this study, we examined the periodicity of Retzius lines in fossil Pongo from South china using polarized light microscope observation of dental ground sections. The periodicities all of the 15 teeth were 9 d. Comparisons of periodicity were made with extant primates, fossil apes and hominins. Periodicity of fossil Pongo from South china was relatively long but fell within the variation of extant Pongo, Gorilla and modern human, and longer than periodicity of Pan and other extant primates. Fossil Pongo from South china was similar to Lufengpithecus and Sivapithecus, shorter than Gigantopithecus and longer than European and African fossil apes and most early hominins in periodicity. Generally, the periodicities of Asian large-body fossil apes were longer than the periodicities of European and African large-body fossil apes in Miocene. Difference among species and trend of evolution in periodicity were analyzed and discussed. We found that periodicity might gradually increase from Proconsul in early Miocene to several fossil apes in Miocene and then Gigantopithecus in Pleistocene. In addition, this study made correlate analysis between periodicity and body mass respectively in males and females of six extant apes and five fossil apes, and found that periodicity positively correlated with body mass.

关键词：周期性变化中国南方大猩猩化石灵长类动物早中新世类人猿显微镜观察

Rate of strong consistency of quasi maximum likelihood estimate in generalized linear models

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Science china Mathematics 2004年第6期47卷 882-893页

作者： YUE Li & CHEN Xiru School of Mathematics and Statistics, Wuhan university, Wuhan 430072, china graduate School, chinese academy of sciences, beijing 100039, china 1. School of Mathematics and Statistics Wuhan University 430072 Wuhan China 2. graduate School Chinese Academy of Sciences 100039 Beijing China

Under the assumption that in the generalized linear model (GLM) the expectation of the response variable has a correct specification and some other smooth conditions, it is shown that with probability one the quasi-likelihood equation for the GLM has a solution when the sample size n is sufficiently large. The rate of this solution tending to the true value is determined. In an important special case, this rate is the same as specified in the LIL for iid partial sums and thus cannot be improved anymore.

关键词： quasi-likelihood function generalized linear models strong consistency

Terrestrial transect study on driving mechanism of vegetation changes

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Science china Earth sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1,2 & ZHOU GuangSheng1 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of sciences, beijing 100093, china 2 graduate university of chinese academy of sciences, beijing 100049, china 1. State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. graduate university of chinese academy of sciences Beijing 100049 China

In terms of chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in china from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast china Transect (NECT) and the North-South Transect of Eastern china (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Recovery of the scale-ε2 pattern by lattice BGK model

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Communications in Nonlinear Science and Numerical Simulation 2001年第1期6卷 40-44页

作者： Guangwu YAN and Li YUAN (Institute of Computational Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china Department of mathematics, Jinn university, Chongchun 130023, china) Inst. of Computational Mathematics Acad. of Math. and System Sciences Chinese Academy of Sciences Beijing 100080 China Department of Mathematics Jilin University Changchun 130023 China

A lattice BGK method for nonlinear chemical reactions is described. Since the equation does not possess the convect terms, we can easily get the equilibrium distribution functions of the lattice BGK models. Using this... 详细信息

关键词： lattice BGK method Turing pattern mosaic structure

A new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem

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Science china(Physics,Mechanics & Astronomy) 2009年第9期52卷 1404-1413页

作者： XU XingBo1,2 & FU YanNing1 1 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 2 graduate university of chinese academy of sciences, beijing 100039, china 1. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China 2. graduate university of chinese academy of sciences Beijing 100039 China

We show that there exists a new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem. In such a solution, the infinitesimal body is confined to the vicinity of a primary and moves on a nearly circular orbit. This orbit is almost perpendicular to the orbital plane of the primaries, where the line of symmetry of the orbit lies. The existence is shown by applying a corollary of Arenstorf's fixed point theorem to a periodicity equation system of the problem. And this existence doesn't require any restriction on the mass ratio of the primaries, nor on the eccentricity of their relative elliptic orbit. Potential relevance of this new class of periodic solutions to real celestial body systems and the follow-up studies in this respect are also discussed.

关键词： periodic orbits spatial restricted three-body problem symmetric orbits averaging