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Earthquake Research in china 1996年第3期10卷 11-23页

作者： Kan Rongju and Hu HuiSeismological Bureau of Yunnan Province,Kunming 650041,chinaYunnan Astronomical observatory,Academia Sinica,Kunming 650011,china

In this paper,the features of medium-term anomalies for strong earthquakes and the criteria for the prediction of such earthquakes are discussed,as well as the feasibility of applying the anomalies of astronomical time-latitude residuals to earthquake prediction and their limitation when applied to imminent-term *** criteria used to identify the anomalies of time-latitude residuals for M≥6.0 earthquakes in Yunnan Province and for M≥7.0 earthquakes around Yunnan are also *** last strong earthquake in the data used for testing passed the whole process of earthquake prediction *** addition,some special features of the case in which anomalies appeared but no strong earthquake followed are also discussed.

关键词： Time-latitude observation Residual anomaly Strong earthquake prediction

Suprathermal particle events observed by WIND spacecraft in interplanetary space during 1995―1999 and their classification

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Science china(Technological Sciences) 2008年第9期51卷 1542-1553页

作者： SUN LingPeng1,2, WU DeJin1 & WANG DeYu1 1 Purple Mountain observatory, Chinese Academy of Sciences, Nanjing 210008, china 2 Graduate School of Chinese Academy of Sciences, Beijing 100049, china Purple Mountain observatory Chinese Academy of Sciences Nanjing China Graduate School of Chinese Academy of Sciences Beijing China

Fifty-five suprathermal particle events were selected from WIND observations between 1995 and 1999. Based on systematic analysis on the observational characteristics of these events a two-parameter (the rising time and the flux ratio of electrons to protons in each event) classification method was proposed to classify these events. The three clas-sified classes are (1) impulsive electron events with the flux ratio of electrons to protons being bigger than 1 and rising time being shorter than 200 min, (2) impulsive proton events with the flux ratio being smaller than 1 and rising time being shorter than 200 min, and (3) gradual proton events with the flux ratio being smaller than 1 and the rising time being longer than 200 min. In the past, "impulsive solar electron events" were under in-tense research. However, because the selection standards of their velocity dispersions or pitch-angle distributions were inadequate, statistical surveys of selected events were dif-ferent from each other and even some conclusions were not consistent with the theory, for example, the relation of type-III solar radio bursts to the "impulsive solar electron events". The first class of impulsive electron events are associated with type-III radio bursts and with clear velocity dispersions; therefore they ought to originate from the Sun. The second class of the events, which have short continuance time and usually are not associated with type-III radio bursts and without velocity dispersion, are still far away from inter-planetary shocks and most of them do not one-to-one correspond to corrotating interact-ing regions (CIRs); such events are possible results of local interplanetary magnetic field reconnection or electromagnetic disturbances. Finally, about 2/3 gradual proton events of the third class occur with interplanetary shocks, the delay times of which are almost equal to the rising time. Some of these events can be understood as particle accelerations by shocks.

关键词： suprathermal particles solar wind plasma solar eruptive activity interplanetary active regions

Recent study of emission line star 3G71

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Chinese Science Bulletin 1998年第6期43卷 470-473页

作者： HANG Hengrong 1,2 and XIA Jianping+1 1. Purple Mountain observatory, Chinese Academy of Sciences, Nanjing 210008, china 2. Joint Laboratory for Optical Astronomy, Chinese Academy of Sciences, Nanjing 210008, china Purple Mountain observatory Chinese Academy of Sciences Nanjing China Joint Laboratory for Optical Astronomy Chinese Academy of Sciences Nanjing China

New spectral observations of 3G71 are presented. The main features of optical spectra which exhibit a lot of forbidden lines and unusual strong H-Balmer emission lines are discussed. Our data, together with its large IRAS infrared color excess and other characteristics, show evidence that the star may be a Herbig Ae/Be star rather than the optical counterpart of Be/X-ray source of 1H2214+589.

关键词： Be/X-ray binary emission line IRAS identification Herbig Ae/Be star.

The ray-tracing mapping operator in an asymmetric atmosphere

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Progress in Natural Science:Materials International 2008年第1期18卷 123-127页

作者： Zhenjie Honga ,b,*,Fan Ye b ,Peng Guo a aShanghai Astronomical observatory,Chinese Academy of Sciences,Shanghai 200030,china bSchool of Mathematics&Information Science,Wenzhou University,Wenzhou 325027,china Shanghai Astronomical observatory Chinese Academy of Sciences Shanghai 200030 China School of Mathematics & Information Science Wenzhou University Wenzhou 325027 China

In a spherically symmetric atmosphere,the refractive index profile is retrieved from bending angle measurements through Abel inte- gral *** horizontal refractivity inhomogeneity becomes significant in the moist low atmosphere,the error in refractivity profile obtained from Abel inversion reaches about 10%.One way to avoid this error is to directly assimilate bending angle profile into numer- ical weather *** paper discusses the 2D ray-tracing mapping operator for bending angle in an asymmetric *** simulating computations,the retrieval error of the refractivity in horizontal inhomogeneity is *** step length of 4 rank Runge– Kutta method is also tested.

关键词： GPS occultation Ray-tracing Data assimilation Runge–Kutta method

Autonomous satellite constellation orbit determination using the star sensor and inter-satellite links data

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 966-974页

作者： GAN QingBo1,2,MA JianBo1 & XU Jin1 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 China Graduate University of Chinese Academy of Sciences Beijing China

A method of autonomous orbit determination for a satellite constellation using a star sensor combined with inter satellite links(ISLs) is *** types of simulated observation data,Three-Satellite Constellation ISLs and background stellar observations by a CCD star sensor,are first *** on these data,an observation equation is built for the constellation joint autonomous orbit determination,in which the simulations are *** accuracy of this method with different orbital determination models are analyzed and compared with regard to the effect of potential measurement *** results show that autonomous satellite constellation orbit determination using star sensor measurement and ISLs data is ***,this paper arrives at several conclusions which contribute to extending this method to a more general satellite constellation.

关键词： satellite constellation star sensor inter-satellite links autonomous orbit determination

Development of superconducting mixers for THz astronomy

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Science china(Information Sciences) 2012年第1期55卷 120-126页

作者： SHI ShengCai1,2 1Purple Mountain observatory,Chinese Academy of Sciences,Nanjing 210008,china 2Key Laboratory of Radio Astronomy,Chinese Academy of Sciences,Nanjing 210008,china Purple Mountain observatory Chinese Academy of Sciences Nanjing China Key Laboratory of Radio Astronomy Chinese Academy of Sciences Nanjing China

The terahertz(THz)regime,loosely defined as 0.1-10 THz,is the last frequency window to be fully explored in *** particular,it is a regime in which there are rich molecular rotation lines and atomic fine structure *** are very important tracers for studying the dynamics of astronomical objects such as stars and planetary *** those spectral lines usually makes use of coherent detectors(i.e.,heterodyne mixers).With sensitivity approaching the quantum limit,superconducting mixers have become the coherent detector of choice in THz *** this paper we mainly introduce the superconducting mixers developed at Purple Mountain observatory and those for international collaborative projects.

关键词： terahertz detection superconducting mixer quantum limit

APPLICATION OF VEGETATION INDEX OF METEOROLOGICAL SATELLITE IN DROUGHT ANALYSIS OF NINGXIA

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干旱区资源与环境 1993年第Z1期7卷 379-381页

作者： Wang Lianxi Hu Wendong Zhang Feng Ningxia Meteorological observatory, Yinchuan 750002, china

There are five channels in NOAA-N series meteorological satellites. The channel No.1 is exactly located in the absorbtion band of vegetation, the channel No. 2 in the strong re-flection one. Therefore the two channels are suitable for monitoring and analysing vegeta-tion. To make certain mathematical value combination of two channels and specify its val-

关键词： Meteorological Satellite Vegetation Index Drought Condition Analysis

What does the Sun tell and hint now?

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Research in Astronomy and Astrophysics 2009年第9期9卷 959-965页

作者： Ke-Jun Li1,2 1 National Astronomical Observatories /Yunnan observatory,Chinese Academy of Sciences,Kunming 650011,china 2 Key Laboratory of Solar Activity,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,china National Astronomical Observatories/Yunnan observatory Chinese Academy of Sciences Kunming 650011 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Some historical records, which have held since the beginning of modern solar activity cycles, are being broken by the present Sun： cycle 23 records the longest cycle length and fall time; latitudes of high-latitude sunspots belonging to a new cycle around the minimum time of the cycle are statistically the lowest at present, compared with those of other cycles; there are only one or no sunspots in a month appearing at high latitudes for 58 months, which is the first time that such a long duration has been observed. The solar dynamo is believed to be slowing down due to：（1） the minimum smoothed monthly mean sunspot number is the smallest since cycle 16 onwards, and even probably among all modern solar cycles; and （2） once the time interval between the first observations of two neighboring sunspot groups is larger than 14 d, it should be approximately regarded as an observation of no sunspots on the visible solar disk, called a spotless event. Spotless events occur with the highest frequency around the minimum time of cycle 24, and the longest spotless event also appears around the minimum time for observations of the Sun since cycle 16. Cycle 24 is expected to have the lowest level of sunspot activity from cycle 16 onwards and even probably for all of the modern solar cycles.

关键词： Sun: activity -- Sun: general -- sunspots

RELATIONSHIP BETWEEN THE VARIATION OF LUNISOLAR TIDAL FORCE AND EARTHQUAKES IN TAI WAN

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Natural Disaster Reduction in china 2002年第2期 36-40页

作者： Zhao Juan 1,3 , Han Yanben 2,3 and Li Zhian 1 (1. Department of Astronomy, Beijing Normal University, Beijing 100875, china 2. Beijing observatory, CAS, Beijing 100012, china 3. National Astronomical observatory, CAS, Beijing 100012, china

The paper presents a discussion of the relationship between the variance ratio of the lunisolar tidal force prior to and after the attacks of the major earthquakes (Ms≥7.0) in Taiwan Province, china in the 20th century. It concludes that a close connection exists between them: the variance of the lunisolar tidal force might be a trigger to the occurrence of disastrous earthquakes in the Province.

关键词： lunisolar tidal force earthquake variance ratio

Numerical simulations of magnetic reconnection in the lower solar atmosphere

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Research in Astronomy and Astrophysics 2011年第2期11卷 225-236页

作者： Xiao-Yan Xu 1,2,Cheng Fang 2,Ming-De Ding 2 and Dan-Hui Gao 2 1 Purple Mountain observatory,Chinese Academy of Science,Nanjing 210008,china 2 Department of Astronomy,Nanjing University,Nanjing 210093,china Purple Mountain observatory Chinese Academy of Science Nanjing 210008 China Department of Astronomy Nanjing University Nanjing 210093 China

Observations indicate that Ellerman bombs （EBs） and chromospheric microflares both occur in the lower solar atmosphere,and share many common features,such as temperature enhancements,accompanying jet-like mass motions,short life-time,and so *** strongly suggest that EBs and chromospheric microflares could both probably be induced by magnetic reconnection in the lower solar *** gravity,ionization and radiation considered,we perform two-dimensional numerical simulations of magnetic reconnection in the lower solar *** influence of different parameters,such as intensity of the magnetic field and anomalous resistivity,on the results are *** result demonstrates that the temperature increases are mainly due to the joule dissipation caused by magnetic *** spectral profiles of EBs and chromospheric microflares are calculated with the non-LTE radiative transfer theory and compared with *** is found that the typical features of the two phenomena can be qualitatively reproduced.

关键词： Sun: chromosphere-- Sun: photosphere -- Sun: magnetic reconnection-- Sun: numerical simulation