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Transverse patterns and spatiotemporal instability of a photorefractive oscillator

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chinese Science Bulletin 1997年第9期42卷 724-729页

作者： ZHUANG Jun and TAN Weihan1. shanghai Institute of Optics and Fine Mechanics, chinese academy of sciences, shanghai 2.1800, china 2. shanghai University, shanghai 2.1800, china shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China shanghai University Shanghai China

IN time realm,instability and chaos phenomena of a nonlinear optical system have been dis-cussed *** recent years,as much interest was attracted to the transverse ef-fects in nonlinear optics,the study was developed t... 详细信息

关键词： photorefractive oscillator spatiotemporal instability transverse patterns.

CO observations of massive star forming regions at different evolutionary phases

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2. XU Ye1,3, SHEN Zhiqiang1,3 & LI Jingjing1,2.1. shanghai Astronomical observatory,{2., shanghai 20003., china 2. Graduate School of the{2., Beijing 100034, china 3. Joint Institute for Galaxy and Cosmology, shanghai Astronomical observatory and the University of Science and Technology of china, shanghai 20003., china shanghai Astronomical observatory Chinese Academy of Sciences Shanghai 200030 China Graduate School of the chinese academy of sciences Beijing 100034 China Joint Institute for Galaxy Cosmology Shanghai Astronomical Observatory the University of Science Technology of china Shanghai 200030 China

The 12.O (J=1-0), 13CO (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of Purple Mountain observatory. Of the observed 9 sources, 13CO cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2. masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 2.566+582. in the observing field of S152.S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2. maser simulta- neously.

关键词： star formation cloud core outflow H2. maser

Polynomial regression calculation of the Earth's position based on millisecond pulsar timing

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Research in Astronomy and Astrophysics 2012年第2期12卷 219-234页

作者： Feng Tian 1,2.Zheng-Hong Tang 1,Qing-Zeng Yan 1,2.and Yong Yu 11 shanghai Astronomical observatory,{2. academy of sciences,shanghai 20003.,china 2.Graduate University of chinese academy of sciences,Beijing 100049,china shanghai Astronomical observatory Chinese Academy of Sciences Shanghai 200030 China Graduate University of chinese academy of sciences Beijing 100049 China

Prior to achieving high precision navigation of a spacecraft using X-ray observations, a pulsar rotation model must be built and analysis of the precise posi- tion of the Earth should be performed using ground pulsar timing observations. We can simulate time-of-arrival ground observation data close to actual observed values before using pulsar timing observation data. Considering the correlation between the Earth＇s position and its short arc section of an orbit, we use polynomial regression to build the correlation. Regression coefficients can be calculated using the least square method, and a coordinate component series can also be obtained; that is, we can calcu- late Earth＇s position in the Barycentric Celestial Reference System according to pulse arrival time data and a precise pulsar rotation model. In order to set appropriate param- eters before the actual timing observations for Earth positioning, we can calculate the influence of the spatial distribution of pulsars on errors in the positioning result and the influence of error source variation on positioning by simulation. It is significant that the threshold values of the observation and systematic errors can be established before an actual observation occurs; namely, we can determine the observation mode with small errors and reject the observed data with big errors, thus improving the positioning result.

关键词： autonomous positioning - millisecond pulsar - pulsar timing - re-gression analysis

Plumb line variation at Tangshan during 1987―1998 and its relation with the earthquakes around

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Science china Earth sciences 2009年第1期52卷 101-107页

作者： LI ZhengXin1,2.& LI Hui3 1 shanghai observatory,{2. academy of sciences,shanghai 20003.,china 2.Institute of Geodesy and Geophysics,{2. academy of sciences,Wuchang 430077,china 3 Institute of Seismology,china Earthquake Administration,Wuchang 430071,china shanghai observatory Chinese Academy of Sciences Shanghai 200030 China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuchang 430077 China Institute of Seismology China Earthquake Administration Wuchang 430071 Chin

Plumb line variations(PLV) at Tangshan during the years of 1987―1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan *** has been found that PLV at Tangshan are related with the 38 earthquakes in this *** appears that the time of an earthquake around Tangshan is usually quite the same when PLV at Tangshan begins moving in opposite direction.

关键词： plumb line variations network in northern china variations of local gravity field earthquakes

Serine racemase expression in mouse cerebral cortex after permanent focal cerebral ischemia

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Acta Pharmacologica Sinica 2004年第4期25卷 38-43页

作者： Li-zhenWANG, Xing-zu ZHU2.Department of Pharmacology, shanghai Institute of Materia Medica, shanghai Institutes for Biological {2., chinese academy of sciences, shanghai 2.12.3, china Department of Pharmacology Shanghai Institute of Materia MedicaShanghai Institutes for Biological Sciences Chinese Academy of Sciences

AIM: To study the alterations of the expressions of serine racemase in C57BL/6 mouse brain after permanent focal cerebral ischemia. METHODS: The mRNA level and the protein level of serine racemase were assayed by semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. The amount of D-serine and L-serine were measured by HPLC. RESULTS: High levels of serine racemase were constitutively expressed in the normal cortex of mouse. At early stage after middle cerebral artery occlusion (MCAO), no significant change in expression of serine racemase was observed in temporoparietal cortex in ipsila- teral hemisphere. However, delayed transient decreases of serine racemase in both mRNA and protein levels were detected from d 6 to d 10 after ischemia. Correspondingly, D-serine concentration also declined in the ipsilateral cortex during this period when compared with the D-serine level in the contralateral cortex. CONCLUSION: Delayed decreases in serine racemase expression and D-serine level occurred in the temporoparietal cortex at the late stage after focal cerebral ischemia.

关键词： D-serine L-serine serine racemase inbred C57BL mice brain ischemia

Entropy of three-dimensional BTZ black holes

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中国科学：物理学、力学、天文学英文版 2004年第3期47卷 277-283页

作者： GAO Changjun1,2.& SHEN Yougen1,2.3,4 1.shanghai Astronomical observatory,{2. academy of sciences,shanghai 20003.,china(mailing address) 2.National Astronomical Observatories,{2. academy of sciences,Beijing 100012.china 3.Institute of Theoretical Physics,{2. academy of sciences,Beijing 100080,china 4.shanghai United Center for Astrophysics,shanghai 2.02.4,china 1. shanghai Astronomical observatory Chinese Academy of Sciences 200030 Shanghai China 2. National Astronomical Observatories Chinese Academy of Sciences 100012 Beijing China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China 4. shanghai United Center for Astrophysics 200234 Shanghai China

The entropies of scalar field and neutrino field are calculated in the background of three-dimensional BTZ black hole. Considering statistical physics,we propose not to consider the superraradiant modes for bosons (Fermion fields do not display supperradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions. The result shows that the neutrino field entropy is 3/2.times the scalar one.

关键词： BTZ black holes, entropy, supperradiant modes.

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2.3 and Xin-Wu Cao1,2.1 shanghai Astronomical observatory,{2., shanghai 20003., china 2.Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, shanghai 20003., china 3 Graduate School of the{2., Beijing 100049, china shanghai Astronomical observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China Graduate School of the chinese academy of sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2.cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 2.8 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

X-ray Powder Diffraction Pattern of Bi_4(SiO_4)_3

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Journal of Materials Science & Technology 1997年第2期13卷 145-148页

作者： Hongchao LIU Changlin KUO (shanghai Institute of Ceramics, chinese academy of sciences, shanghai 2.0050, china) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

In cooperation with figure-of-merits the Rietveld analysis can appraise both angular and intensity data of powder diffraction. In this work, X-ray diffraction pattern of Bi4(SiO4)3 was redetermined with intensity figure-of-merits, which qualify agreement between observed and calculated relative intensities. F30 is 158.90 (0.0059, 32., intensity figure of merit Rint is 8.7, I2.(17), 8.0. The values of figure-of-merits show that the data of JCPDS cards are distorted. Both the experimental and calculated peak positions and heights are listed in detail.

关键词： SiO4 X-ray Powder Diffraction Pattern of Bi4 Bi

Valence Distribution in AT_xV_(6-X)O_(11) Compounds

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Journal of Materials Science & Technology 1999年第6期15卷 551-554页

作者： Hongchao LIU and Changlin KUO(shanghai Institute of Ceramics, chinese academy of sciences, shanghai 2.0050, china) chinese Acad Sci Shanghai Inst Ceram Shanghai 200050 Peoples R China

The distribution of trivalent and tetravalent cations in several ATxV6-xO11 compounds was quantitatively studied by the bond valence method. In SrV6O11, the M(3) sites were mainly occupied by trivaient cations; while M(1) and M(2. sites were shared by trivalent and tetravalent cations, the relative content of tetravalent at M(1) sites was higher than at M(2. sites. During substitution process, the trivalent cations preferred to occupy M(3) sites, tetravalent ones preferred to occupy M(2. sites. The occupancy of trivalent and tetravalent cations at M sites would change with the substitution

关键词： AT X)O Valence Distribution in AT_xV Compounds