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The microscopic approach of sdgIBM-1 and study of the ^(192.190,188)Os isotopes

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Nuclear Science and Techniques 1998年第2期9卷 69-73页

作者： Zhang Zhan-Jun Sang Jian-Ping Pan Wu-Ming Liu Yong (Institute of Particle physics, Hua-Zhong normal {2., Wuhan 430079, department of physics,Wuhan {2., Wuhan 430072. department of physics, Hua-Zhong normal {2., Wuhan 430079) Institute of Particle physics Hua-Zhong Normal University Wuhan 430079 China department of physics Wuhan University Wuhan 430072 China department of physics Hua-Zhong Normal University Wuftan 430079 China

From the shell model configurations, valence nucleon effective interactions and fermion E2.transition operator, the sdgIBM-1 Hamiltonian and boson E2.transition operator are derived micoscopically with the help of Dyson boson expansion technique. Spectra and reduced E2.matriX elements are calculated for the 192.190,188Os isotopes. Present theoritical results fit experimental data quite well.

关键词：锇同位素研究微观方法

Global Existence of Positive Periodic Solutions for a Distributed Delay Competition Model

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Acta Mathematicae Applicatae Sinica 2003年第3期19卷 491-498页

作者： Xian-yi Li, De-ming Zhudepartment of Mathematics, East china {2. university, Shanghai 2.0062. china department of Mathematics and physics, Nanhua university, Hengyang 42.001, china department of Mathematics East China Normal University Shanghai 200062 China department of Mathematics and physics Nanhua University Hengyang 421001 China

By using the continuation theorem of Mawhin’s coincidence degree theory, a sufficient condition is derived for the existence of positive periodic solutions for a distributed delay competition model , where r 1 and r 2./SUB> are continuous ω-periodic functions in R + = [0,∞) with are positive continuous ω-periodic functions in R + = [0,∞), b i (i = 1, 2. is nonnegative continuous ω-periodic function in R + = [0,∞), ω and T are positive constants, and . Some known results are improved and extended.

关键词： Global existence positive periodic solution coincidence degree distributed delay model

Rose solutions with three petals for planar 4-body problems

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Science china Mathematics 2010年第12期53卷 3085-3094页

作者： DENG ChunHua 1,2., ZHANG ShiQing 1, & ZHOU Qing 3 1 Yangtze Center of Mathematics and College of Mathematics, Sichuan university, Chengdu 610064, china 2.Faculty of Mathematics and {2., Huaiyin Institute of Technology, Huai’an 2.3001, china 3 department of Mathematics, East china normal university, Shanghai 2.0062. china 1. Yangtze Center of Mathematics and College of Mathematics Sichuan University Chengdu 610064 China2. Faculty of Mathematics and Physics Huaiyin Institute of Technology Huai’an 223001 China3. Department of Mathematics East China Normal University Shanghai 200062 China

For planar Newtonian 4-body problems with equal masses, we use variational methods to prove the existence of a non-collision periodic choreography solution such that all bodies move on a rose-type curve with three pet... 详细信息

关键词： 4-body problems with Newtonian potentials rose solutions with three petals winding numbers variational minimization methods

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, Nanjing 2.0093,{2. 2. Shanghai Observatory, Chinese Academy of Sciences, Shanghai 2.0030,{2. 3. physics department, Nanjing normal university, Nanjing 2.0097,{2. 4. Beijing Astronomical Observatory, Chinese Academy of Sciences, Beijing 100080,{2. 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 1994-07-2., 2. 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.

Latest cosmological constraints on Cardassian expansion models including the updated gamma-ray bursts

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Research in Astronomy and Astrophysics 2011年第9期11卷 1019-1030页

作者： Nan Liang Pu-Xun Wu Zong-Hong Zhu department of Astronomy Beijing Normal University Beijing 100875 China Center for High Energy physics Peking University Beijing 100871 China Center of Nonlinear Science and department of physics Ningbo University Ningbo 315211 China

We constrain the Cardassian expansion models from the latest observa- tions, including the updated Gamma-ray bursts （GRBs）, which are calibrated using a cosmology independent method from the Union2.compilation of type Ia supernovae （SNe Ia）. By combining the GRB data with the joint observations from the Union2.SNe Ia set, along with the results from the Cosmic Microwave Background radia- tion observation from the seven-year Wilkinson Microwave Anisotropy Probe and the baryonic acoustic oscillation observation galaxy sample from the spectroscopic Sloan Digital Sky Survey Data Release. we find significant constraints on the model oarameters of the original Cardassian model ΩM0=0.2.2.0.014^0.015,n=0.03-0.05^＋0.05 and n=-0.16-3.2.^＋0.2.,β=0.76-0.58^＋0.34 of the modified polytropic Cardassian model, which are consistent with the ACDM model in a l-or confidence region. From the reconstruction of the deceleration parameter q（z） in Cardassian models, we obtain the transition redshift ZT = 0.73 ± 0.04 for the original Cardassian model and ZT = 0.68 ± 0.04 for the modified polytropic Cardassian model.

关键词： gamma-rays bursts -- cosmology cosmological parameters

The numerical method for three-dimensional impact with friction of multi-rigid-body system

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Science china(physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1,2. LIU Caishan2.& CHEN Bin2.1. Beijing Institute of Graphic Communication, Beijing 102.00, china 2. department of Mechanics & Engineering Science, Peking {2., Beijing 100871, china Beijing Institute of Graphic Communication Beijing 102600 China department of Mechanics & Engineering Science Peking University Beijing 100871 China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy physics, Chinese Academy of Sciences, Beijing 100049, china 2. Graduate School of Chinese Academy of Sciences, Beijing 100049, china 3. department of physics, Zhoukou normal university, Zhoukou 466100, china 4. Research Imaging Center, university of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, Institute of Automation, Chinese Academy of Sciences, Beijing 100049, china 6. department of physics, Zhejiang university, Hangzhou 31002., china) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]department of physics Zhoukou Normal University Zhoukou China [d]Research Imaging Center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing China [f]department of physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2. ZHUANG Guoshun1,2.3, CHEN Jianmin2.& XUE Huaxin2.1. Center for Atmospheric Environment Study, department of Chemistry, Beijing normal {2., Beijing 100875, china 2. Center for Atmospheric Chemistry Study, department of Environ- mental Science and Engineering, Fudan {2., Shanghai 2.0433, china 3. LAPC/NZC, Institute of Atmospheric physics, NZC/LAPC, Chinese Academy of Sciences, Beijing 10002., china Center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for Atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2.Al2.3. Sulfate is the dominant species of sulfur on the surface. SiO2.and Al2.3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 2., 2.02. while Fe2.SO4)3, one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

Behavior of gravity waves with limited amplitude in the vicinity of critical layer

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Chinese Science Bulletin 2002年第18期47卷 1547-1550页

作者： WU Shaoping & Yl FanWuhan Institute of physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, china {2. of Radio Science and Technology, Wuhan university, Wuhan 430072. china {2. of physics, Huazhong normal Univ Wuhan Institute of physics and Mathematics Chinese Academy of Sciences Wuhan China department of physics Huazhong Normal University Wuhan China department of Radio Science and Technology Wuhan University Wuhan China

By using the FICE scheme, a numerical simulation of three-dimensional nonlinear propagation of gravity wave packet in a wind-stratified atmosphere is presented. The whole nonlinear propagation process of the gravity wave packet is shown; the propagation behavior of gravity waves in the vicinity of critical layer is analyzed. The results show that gravity waves encounter the critical layer when propagating in the fair winds whose velocities increase with height, and the height of critical layer propagating nonlinearly is lower than that expected by the linear gravity waves theory; the amplitudes of gravity waves increase with height as a whole before gravity waves encounter the critical layer, but the increasing extent is smaller than the result given by the linear theory of gravity waves, while the amplitudes of gravity waves reduce when gravity waves meet the critical layer; the energy of wave decreases with height, especially at the critical layer; the vertical wavelength reduces with the height

关键词： gravity waves critical layer FICE scheme simulation.