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Chinese Science Bulletin 1998年第1期43卷 72-75页

作者： CHEN Jun\+1, JI Junfeng\+1, SU Yuanxia\+2 and LU Huayu\+3.. department of Earth Sciences, nanjing university, nanjing 2.0093. china 2. Center of Material Analysis, nanjing university, nanjing 2.0093. china 3. Xi’an Laboratory of Loess and Qu department of Earth Sciences Nanjing University Nanjing China Center of Material Analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Mn 2+ EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus Mn 2+ EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of Mn 2+

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese Science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second Institute of Oceanography, State Oceanic Administration, Hangzhou 3.0012, china 2 Center for Materials Analysis, nanjing university, nanjing 2.0093. china 3. {3. of Earth Sciences, nanjing university, nanjing 2.0093. china Second Institute of Oceanography State Oceanic Administration Hangzhou China Centu for Materials Analysis Nanjing University Nanjing China department of Earth Sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

Line Broadening in a Limb Flare: Derivation of Macro-turbulent Velocity Fields

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Chinese Journal of astronomy and Astrophysics 2002年第3期2卷 277-286页

作者： Ying Liu and Ming-De Dingdepartment of astronomy, nanjing university, {3. 2.0093 department of astronomy Nanjing University Nanjing 210093

The line profiles of Ha in a limb flare on 1998 November 11 appear to be unusually broadened. It is considered that macro-turbulence (or macroscopic mass motions) may be one of the main causes. We use an inversion technique to extract the probability distribution of the line-of-sight velocity in the flare. There exist some differences between the velocity distributions deduced from Ha and from Ca II λ8542, which may be because the two lines depend differently on the temperature and velocity. Since the loop density is high, we obtain a rather short cooling time (several tens of seconds) from the hot X-ray loops to the cool loops visible in Ha. Possible origins of the large scale motions are discussed.

关键词： Sun: flares - Sun: atmospheric motions - Line: profiles

Constraint on the counter-jet emission in gamma-ray burst afterglows from GRB 980703

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Science china(Physics,Mechanics & astronomy) 2010年第S1期53卷 259-261页

作者： WANG Xin,HUANG YongFeng & KONG SiWei department of astronomy,nanjing {3.,nanjing 2.0093.china 1. department of astronomy Nanjing University Nanjing 210093 China

We present a numerical investigation of emission from the receding jet of gamma-ray *** is found that the peak time of the receding jet emission is significantly affected by synchrotron self-absorption in radio ***,the receding jet component is generally very *** is observable mainly for those nearby events in a dense *** GRB 980703.has been observed in radio wavelengths for more than 1000 days,we argue that the receding jet emission still has not been detected for this ***,it is completely submerged by the host galaxy.

关键词： gamma rays:bursts ISM:jets and outflows methods:numerical

Binomial coefficients,Catalan numbers and Lucas quotients

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Science china Mathematics 2010年第9期53卷 2473-2488页

作者： SUN ZhiWei department of Mathematics,nanjing university,nanjing 2.0093.china 1. department of Mathematics Nanjing University Nanjing 210093 China

Let p be an odd prime and let a,m ∈ Z with a > 0 and p ︱ *** this paper we determinep ∑k=0 pa-1(2k k=d)/mk mod p2 for d=0,1;for example,where(-) is the Jacobi symbol and {un}n≥0 is the Lucas sequence given by u0 =... 详细信息

关键词： congruences binomial coefficients Catalan numbers Lucas quotients

Formation flying in elliptic orbits with the J_2 perturbation

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Research in astronomy and Astrophysics 2012年第11期12卷 1563-1575页

作者： Xi-Yun Hou, Yu-Hui Zhao and Lin Liu School of astronomy and Space Science, nanjing university, nanjing 2.0093. china Institute of Space Environment and Astrodynamics, nanjing university, nanjing 2.0093. china School of astronomy and Space Science Nanjing University Nanjing 210093 China Institute of Space Environment and Astrodynamics Nanjing University Nanjing 210093 China

Relative dynamics between the chief satellite and the deputy ones in for- marion flying is crucial to maintaining the formation. A good choice of the forma- tion usually requires a lower control frequency or less control energy. For formation flying missions in highly elliptic orbits, the well-known C-W equation is not accu- rate enough. Instead, Lawden＇s equation is often used. First, the solution to Lawden＇s equation with a very simple form is deduced. Then the J2 perturbation is added. It is found that Lawden＇s solution is not necessarily valid when the J2 perturbation is con- sidered. Completely discarding Lawden＇s solution and borrowing the idea of mean orbit elements, two rules to initialize the formation are proposed. The deviation speed is greatly reduced. Different from previous studies on the J2 perturbation, except for the relatively simple expression for the semi-major axis, the tedious formulae of the long period terms and the short period terms of other orbital elements are not used. In addition, the deviation speed is further reduced by compensation of the nonlinear effects. Finally, a loose control strategy of the formation is proposed. To test the ro- bustness of this strategy, a third body perturbation is added in numerical simulations.

关键词： celestial mechanics

Time of impact of fragment P2 of comet SL 9 on Jupiter

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Chinese Science Bulletin 1997年第5期42卷 396-398页

作者： ZHOU Hongnan,QIAN Bochen, HUANG Keliang and LI Qibin1. department of astronomy, nanjing university,{3. 2. Shanghai Observatory, Chinese Academy of Sciences, Shanghai 20003., china 3. Physics department, nanjing Normal university, nanjing 210097, china 4. Beijing Astronomical Observatory, Chinese Academy of Sciences, Beijing 100080, china department of astronomy Nanjing University Nanjing China Shanghai Observatory Chinese Academy of Sciences Shanghai China Physics department Nanjing Normal University Nanjing China Beijing Astronomical Observatory Chinese Academy of Sciences Behijing China

FROM 1994-07-16 to 1994-07-22, 21 fragments of comet SL 9 impacted against Jupiter in succession. During the impact period the impact of fragments D, E, K, N, P2 and S was observed in china. We used a 1.56-m telescope with the CCD camera of Shanghai Observatory to monitor Jupiter and its Galilean Satellites, obtaining 1000 high-quality images at B, V, I wave bands. Our data on optical wave bands are rather complete and valuable in the world. Specially, we got some images of Jupiter, Io and Europa in the impact time of fragment P2 impacting against Jupiter. This will help us understand the precise time, position, depth and energy of the P2’s collision. In this note, we report the impact time of fragment P2 of comet SL 9 and Jupiter. Since the impact of comet SL 9 was expected to take place on the side of Jupiter

关键词： comet comet Shoemaker-Levy 9 impacting against Jupiter impact time.

On contactomorphism group of contact structure overtwisted at infinity on R^3

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Science china Mathematics 2007年第8期50卷 1087-1092页

作者： Li YU department of Mathematics,nanjing university,nanjing 2.0093.china department of Mathematics Nanjing University Nanjing 210093 China

We compute all the homotopy groups of the compactly supported contactomorphism group of a contact structure on R^3.which is overtwisted at infinity.

关键词： contactomorphism overtwisted contact structure

A new method for imaging faint objects nearby a bright source

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Chinese Science Bulletin 2000年第3期45卷 201-207页

作者： YE Binxun & CHU Yi1. Beijing Astronomical Observatory, Chinese Academy of Sciences, Beijing 100012, china 2. NAOCAS, Beijing 100012, china 3. department of astronomy,{3., nanjing china Correspondence should be addressed to Ye Binxun Beijing Astronomical Observatory Chinese Academy of Sciences Beijing China NAOCAS Beijing China department of astronomy Nanjing University Nanjing China

In astronomical observation, it is difficult to obtain the image of faint objects in the peripheral area around a bright celestial body. in order to solve the problem, a new method is designed and experimented, which is called the separation readout technique (SRT). SRT is different from either the traditional coronagraphy or the newly-developed anti-blooming CCD technique, and allows an enough-long exposure to the faint objects in the area around a bright celestial body with the well-preserved bright body’s image in one frame. This paper describes in detail the principle of SRT, the computer simulation, the experimental devising and result of SRT observation on a telescope.

关键词： astronomyical methods CCD imaging SRT.

A NEW CLASS OF UNIFORMLY SECOND ORDERACCURATE DIFFRENCE SCHEMES FOR 2D SCALAR CONSERVATION LAWS

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Journal of Computational Mathematics 1997年第4期15卷 311-318页

作者： Juan Cheng(department of Aerodynamics, nanjing university of Aeronautics & Astronautics,nanjing, {3.)Jia-zun Dai (department of Mathematics, Physics and Mechanics, nanjing university of Aeronautics & Astronautics, nanjing, {3.) 南京航空航天大学空气动力学系江苏南京南京航空航天大学数学系江苏南京

In this paper, concerned with the Cauchy problem for 2D nonlinear hyperbolic conservation laws,we construct a class of uniformly second order accurate finite difference schemes, which are based on the E-schemes. By applying the conver gence theorem of Coquel-Le Floch [1], the family of approximate solutions defined by the scheme is proven to converge to the unique entropy weak L∞-solution. Furthermore, some numerical experiments on the Cauchy problem for the advection equation and the Riemann problem for the 2D Burgers equation are given and the relatively satisfied result is obtained.

关键词： Math A NEW CLASS OF UNIFORMLY SECOND ORDERACCURATE DIFFRENCE SCHEMES FOR 2D SCALAR CONSERVATION LAWS high Ph