Preface: Key technologies for enhancing the performance of FAST     

Peng Jiang  Zhi-Qiang Shen  Ren-Xin Xu 《天文和天体物理学研究(英文版)》2020,(5):63-64

The Five-hundred-meter Aperture Spherical radio Telescope(FAST)passed its national acceptance inspection on 2020 January 11.This special issue includes a total of 15 papers,which are selected to introduce the status of FAST’s performance and demonstrate the key technologies applied to FAST.The presented performance parameters can provide an important reference for scientists to propose observations with FAST.The key technologies presented in these papers include design and implementation in the measurement and control system,electromagnetic compatibility system,and receiver system.Finally,scientific achievements obtained by FAST during the commissioning phase are also reported.  相似文献   

A Kinematical Calibration of the Galactocentric Distance     

Ming Shen  Zi Zhu Department of Astronomy  Nanjing University  Nanjing   《中国天文和天体物理学报》2007,7(1):120-128

1 INTRODUCTION The distance to the Galactic center R0 is a fundamental constant for astronomy and astrophysics. Most determinations of astronomical quantities are directly connected with the Galactic distance scale, e.g., the rotational speed of our Galax…  相似文献   

Rotation Periods of Nine ROSAT Selected Solar-Type Stars     

Li-Feng Xing Shuang-Yi Zhao Wei Su Yan Shen Xiao-Bin Zhang Jian-Yan Wei 《中国天文和天体物理学报》2007,7(4):551-557

We monitored 16 X-ray selected young solar-type stars for light variation and found appreciable periodic light variability with amplitudes of a few hundredths of a magni-tude in nine of the objects. Using the method of Phase Dispersion Minimization (PDM) and Fourier analysis (software PERIOD04), the rotation periods of these stars were determined from the photometric data. The rotation periods of all nine stars are shorter than about 3days. It is suggested that, as with the Pleiades cluster, small amplitude light variations are quite common among young solar-type stars with rotation periods around 3 days or less. This gives further evidence for the spin up of solar-type stars predicted by models of angular momentum evolution of pre-main sequence stars.  相似文献   

Probabilistic Estimation of Hazard on Engineering Site Based on the Intensity of Historic Earthquakes and A Preliminary Comparison with Seismic Hazard Analysis     

Zhang Jie  Shen JianwenSeismological Bureau of Anhui Province  Hefei  China 《中国地震研究》1995,(1)

This paper introduces a new method to estimate the seismic hazard on engineering site.The method is mainly based on intensity data of historical earthquakes.The obvious feature of the method is to use some ideas of seismic hazard analysis and considering regional seismicity tendency.The authors depict the comprehensive method to estimate the related parameters and predict the seismic hazards for 14 sites as practical examples.Some problems are also discussed.Compared with seismic hazard analysis,this method has certain advantages,such as simpler computation,lower uncertainty and smaller sensitivity factor.Moreover total hazard P(I≥i)of a site can be examined with real historic data.The result given by the method in this paper can be more stable than that given by seismic hazard analysis nowadays.  相似文献   

Establishment of the GPS Crustal Deformation Monitoring Network in North China   总被引：1，自引：0，他引：1  

Li Yanxing  Shen Jianhua  and Wang MinFirst Crustal Deformation Monitoring Center  SSB  Tianjin ChinaDepartment of Scientific Programming  Earthquake Monitoring  SSB. Beijing China 《中国地震研究》1995,(3)

The Global Positioning System (GPS) is a new method to monitor the crustal deformation for earthquake prediction.Now a four-dimensional crustal deformation monitoring network applying GPS techniques has been established in North China,which is an important seismic monitoring area.Results with high precision have been achieved in the first measurement since a series of advanced methods and measures were adopted,and thus a good foundation has been laid for future researches on earthquake prediction and geodynamics.  相似文献   

Cretaceous-Eogene Ostracod Assemblages in Henan and Their Evolutionary Features     

Zhang Shen Jidong Oil Exploration &. Development Corp.  Tanghai  Hebei Fei Zhenbi 《《地质学报》英文版》1995,69(1):99-110

This paper studies a large number of Cretaceous-Eogene ostracod fossils in the Meso-Cenozoic Nanyang, Zhoukou, Rendian, Luoyang, Lingbao, Tantou and Kaifeng basins of Henan. Eight ostracod assemblages have been recognized. This paper discusses their geographical distribution and geological ages as well as their features and evolutional trends. Besides, it also deals with the palaeoclimate under which the various assemblages lived and the significance in petroleum exploration.  相似文献   

APS系列解析测图仪精度分析     

胡Shen 《测绘科技》1993,(1):33-39

  相似文献   

Palinspastic Reconstruction for Tectonics of Northeast China and Its Vicinity     

Liu Xianwen Meng Xiangang Institute of Geomechanics  Chinese Academy of Geological Sciences  Beijing Tamaki Kensaku Ocean Research Institute  University of Tokyo  Tokyo  Japan Shen Ninghua Ge Xiaohong Department of Earth Sciences  Cha 《中国地质大学学报(英文版)》1998,9(3)

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青岛观象台海尔—波普慧星观测     

孙寿Shen  张春生 《紫金山天文台台刊》1998,17(3):53-57

中国科学院紫金山天文台青岛观象台从1996年4月开始到1995年5月1日结束,在138个观测夜,共拍摄Hale-Bopp彗星底片508张。发现:Hale-Bopp彗星在1996年9月24日的一次爆发,1996年10月26日,11月13日的两次可能爆发。在1996年9月23日的底片上,Hale-Bopp呈现巨大的喷流。在1997年2月8日至5月1日期间,Hale-Bopp彗星彗头内存在大量壳层结构。  相似文献   

Pelagic Manganese Nodules--A New Type of Oncolites     

Bian Lizeng  Lin Chengyi  Zhang Fusheng  Du De''an  Chen Jianlin  Shen Huadi Department of Earth Sciences Centre for Materiale Analysis  Nanjing University  Jiangsu Second Institute of Oceanography  State Oceanic Administration  Hangzhou  Zhejiang Liu Xinzhu 《《地质学报》英文版》1997,71(1):43-48

Pelagic manganese nodules from the East Pacific Ocean have been studied using polarizing,scanning electron and transmission electron microscopes. It has been revealed that the manganesenodules are composed of cores and stromatolite coatings. The structures and textures of thesenodules are peculiar to oncolite. Consequently, the pelagic manganese nodules are manganeseoncolites. Based on the stromatolites in the coatings, the manganese oncolites from the East Paci-fic Ocean can be divided into two types. One is smooth on surface and dense inside. Its coatingsare composed mainly of Minima. The other has a knobby surface and is loose internally. Itscoatings consist mainly of Admirabilis. The TEM investigation has also revealed that the con-structors of the manganese oncolites are ultra-microbes. The Minima is constructed byMiniactinomyces chinensis sp. nov. and the Admirabilis is built by Spirisosphaerospora pacifica sp.nov.  相似文献