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Microfacies and diagenetic alteration in a semi-deep to deep lacustrine shale: The Yanchang Formation in the Ordos Basin, China

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Petroleum Science 2024年第3期21卷 1524-1538页

作者： Bin Bai Jing-Yue Hao ling Fu Yu-Xi Liu jian-Peng wang Lan wang Kevin GTaylor Lin Ma PetroChina Research Institute of Petroleum Exploration and Development Beijing100083China Department of Earth and Environmental sciences University of ManchesterM139PLUK College of Earth sciences Jilin UniversityChangchun130061jilinChina Department of Chemical Engineering University of ManchesterM139PLUK

The mineralogical development and diagenetic sequence of lacustrine shales in the Chang 7 Member of the Yanchang Formation in the Ordos Basin are detailed studied.A model of their depositional system and a diagenetic diagram are proposed in this *** detailed petrographic,mineralogical,and elemental analyses,four distinct shale types are identified:argillaceous shale,siliceous shale,calcareous shale,and carbonate,clay,and silt-bearing *** main diagenetic process in argillaceous shale is the transformation of illite to smectite,negatively impacting shale *** shale undergoes carbonate cementation and quartz dissolution,contributing to increased porosity,particularly in *** shale experiences diagenesis characterised by carbonate formation and dissolution,with a prevalence of *** carbonate,clay,and silt-bearing shale,the dissolution of K-feldspar contributes to illitization of *** shale,characterised by more clay minerals and lower mesopore volume,is identified as a potential hydrocarbon *** shale,with the highest pore volume and abundant inter-mineral pores,emerges as a promising shale oil *** findings contribute to a comprehensive understanding of shale properties,aiding in the prediction of shale oil exploration potential in the studied area.

关键词： Ordos Basin Yanchang Formation Chang 7 Member Diagenesis Microfacies

Discrepancy between infrared and optical emission in some Be stars

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chinese Science Bulletin 2002年第18期47卷 1511-1513页

作者： LIU Qingzhong & WEI jianyanPurple Mountain Observatory, chinese academy of sciences, Nanjing210008, China national {3. observatories, chinese academy of sciences, beijing 100012, China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China national astronomical observatories Chinese Academy of Sciences Beijing China

An expanding ring model is put forward to investigate the original regions of Ha line emission and infrared excess emission in Be stars, by taking optical depth into account. We find that the two regions depend strongly on the physical properties of the envelope of Be stars such as the initial density and density structure. This model can be used to qualitatively interpret the disagreement between the near infrared excess and the equivalent width (EW) of Ha emission line, as observed in some Be stars.

关键词： Be star emission line near infrared excess.

A New Catalogue of Fine Structures Superimposed on Solar Microwave Bursts

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chinese Journal of Astronomy and Astrophysics 2004年第2期4卷 176-188页

作者： Qi-Jun Fu, Yi-Hua Yan, Yu-Ying Liu, Min wang and Shu-Juan wangnational {3. observatories, chinese academy of sciences, beijing 100012 fuqijun2002@*** national astronomical observatories Chinese Academy of Sciences Beijing 100012

The 2.6-3.8 GHz, 4.5-7.5 GHz, 5.2-7.6 GHz and 0.7-1.5 GHz componentspectrometers of Solar Broadband Radio Spectrometer (SBRS) started routine observations,respectively, in late August 1996, August 1999, August 1999, and June 2000. They just managed tocatch the coming 23.d solar active maximum. Consequently, a large amount of microwave burst datawith high temporal and high spectral resolution and high sensitivity were obtained. A variety offine structures (FS) superimposed on microwave bursts have been found. Some of them are known, suchas microwave type Ⅲ bursts, microwave spike emission, but these were observed with more detail;some are new. Reported for the first time here are microwave type U bursts with similar spectralmorphology to those in decimetric and metric wavelengths, and with outstanding characteristics suchas very short durations (tens to hundreds ms), narrow bandwidths, higher frequency drift rates andhigher degrees of polarization. Type N and type M bursts were also observed. Detailed zebra patternand fiber bursts at the high frequency were found. Drifting pulsation structure (DPS) phenomenaclosely associated with CME are considered to manifest the initial phase of the CME, andquasi-periodic pulsation with periods of tens ms have been recorded. Microwave 'patches', unlikethose reported previously, were observed with very short durations (about 3.0 ms), very high fluxdensities (up to 1000 sfu), very high polarization (about 100% RCP), extremely narrow bandwidths(about 5%), and very high spectral indexes. These cannot be interpreted with the gyrosynchrotronprocess. A superfine structure in the form of microwave FS (ZPS, type U), consisting of microwavemillisecond spike emission (MMS), was also found.

关键词： sun: flares sun: radio radiation instrumentation: spectro-graphs

“Double dawn”eclipse and the rotational variation of the earth

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chinese Science Bulletin 2000年第11期45卷 988-991页

作者： ZHANG Peiyu & HAN Yanben1. Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, China 2. beijing astronomical Observatory, chinese academy of sciences, beijing 100012, national astronomical Observatory, chinese academy of sciences, beijing 100012, China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China beijing astronomical Observatory Chinese Academy of Sciences Beijing national astronomical Observatory Chinese Academy of Sciences Beijing China

A record of 'double dawn' at State Zheng in the first year of the reign of King Yi in Western Zhou Dynasty in the chronicle 'Bamboo Annals' (Zhushu Jinian) is discussed. We think that it may be a record of an annular solar eclipse happening in 899 BC. The record and the AT, which describes the secular variation of the earth’s rotation, are analyzed and discussed.

关键词： solar eclipse earth’s rotation.

Possible effect of solar activity on variation of the tree-rings of a 500 a platycladus orientalis at the Mausoleum of Emperor Huang

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Science China(Physics,Mechanics & Astronomy) 2009年第4期52卷 631-639页

作者： FENG Bo1,2 & HAN YanBen1 1 Xi’an Institute of Posts & Telecommunications,Xi’an 710061,China 2 national astronomical observatories,{3.,beijing 100012,China Xi’an Institute of Posts & Telecommunications Xi’an 710061 China national astronomical observatories Chinese Academy of Sciences Beijing 100012 China

The variation of the tree-ring's index of a platycladus orientalis at the Mausoleum of Emperor Huang and of a long series of sunspots relative number during AD1470-1974 are analyzed by using the wavelet power spectrum method,and their variation characters are also discussed. It is determined that the tree-ring's variation has cycles of approximate 2-7,11,93.and 150 a. Two data series are used for analyzing sunspot relative number(SSN) variation. First,the analysis of the annual average SSN during AD1700-1974 proved that variation cycles are about 11,50,and 93.a; then,the data during AD1465-1975 obtained from the decadal average SSN train over 7000 a reconstructed on the geomagnetic data is analyzed and its variation cycles are about 50,90,and 160 a. Besides the tree-rings cycle of 2-7 a is commonly considered to be related to ENSO,while 11 a cycle is related to solar Schwabe cycle; in addition,it is possible that the cycles of 90 and150 a are likely to be related to solar Gleissberg cycle and Suess cycle. The correlations between them are possibly due to the effect of solar activity on the climate and additionally on the tree's growth.

关键词： tree-ring solar activity climate change wavelet spectrum

1RXS J23.953.9+062814: a New SU UMa Dwarf Nova below the Period Minimum

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chinese Journal of Astronomy and Astrophysics 2001年第6期1卷 483-486页

作者： jian-Yan Wei, Xiao-Jun jiang, Da-Wei Xu, Ai-Ying Zhou and Jing-Yao Hu national {3. observatories, chinese academy of sciences, beijing 100012 national astronomical observatories Chinese Academy of Sciences Beijing 100012

RXS 123.953.9+062814 was identified as a cataclysmic variable by Wei et al. (1999). Four low-resolution spectra of 1RXS J23.953.9+062814 were obtained with the 2.16-rn telescope of the national astronomical observatories, of which two were at outburst, and two were at quiescence. The system is about 16.8 B and 16.5 V at quiescence, and 12.6 B and 12.6 V at outburst. The quiescent spectra were dominated by double-peaked Balmer emissions, which indicates a hydrogen-rich system with a high-inclination accretion disc. MgH and TiO absorption bands appeared in the quiescent spectrum which implies a companion with a spectral type of early M dwarf. If we take it as a MO dwarf, then the system is located at a distance of 3.0 pc with a proper motion velocity 150 km s-1. The superhump period of 0.0463.1 days was confirmed by our V photometry. The short period and the hydrogen-rich nature reveal that this system is another SU Ursae Majoris-type dwarf nova below the period minimum after V485 Centauri. 1RXS J23.2953.9+062814 is one of the most important systems for studying the evolutionary scenario of cataclysmic variables since it is much brighter than V485 Cen.

关键词： stars: dwarf novae - stars: cataclysmic variables: individual: 1RXS J23.953.9 +062814

The Influence of Panel Gaps on the System NoiseTemperature of the FAST

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chinese Journal of Astronomy and Astrophysics 2001年第2期1卷 190-194页

作者： Yan Su and Guo-Ding Li (1 beijing astronomical Observatory, national astronomical observatories, chinese academy of sciences, beijing 100012 2 The Laboratory of Microwave and Digital Communication Technology, Tsinghua University, beijing 100084) The Laboratory of Microwave and Digital Communication Technology Tsinghua University Beijing 100084

A Five-hundred-meter Aperture Spherical Telescope (FAST), the largest single dish in the world, is proposed to be built in one of the karst depressions in Guizhou province. The main spherical reflector is to consist of about two thousand small panels, which can be adjusted to fit a paraboloid in real time. There are many slit-like gaps across the aperture due to manufacturing errors thermal effects and deviations between a sphere and a paraboloid. The influence of the energy leakage of the narrow gaps on the system noise temperature of the FAST reflector is discussed in this paper.

关键词： telescopes - methods: analytical - energy leakage

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,chinese academy of sciences,Shanghai 20003.,China(mailing address) 2.{3. astronomical observatories,chinese academy of sciences,beijing 100012,China 3.Institute of Theoretical Physics,chinese academy of sciences,beijing 100080,China 4.Shanghai United Center for Astrophysics,Shanghai 20023.,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.

A new method of ionospheric-free hybrid differential positioning based on a double-antenna CAPS receiver

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Science China(Physics,Mechanics & Astronomy) 2009年第3期52卷 368-375页

作者： GUO JinYun1,2, HAN YanBen1 & CHANG XiaoTao3.1 national astronomical observatories, {3., beijing 100012, China 2 College of Geodesy and Geomatics, Shandong University of Science and Technology, Qingdao 266510, China 3.chinese academy of Surveying and Mapping, beijing 10003., China 1. national astronomical observatories Chinese Academy of Sciences Beijing 100012 China 2. College of Geodesy and Geomatics Shandong University of Science and Technology Qingdao 266510 China 3. chinese academy of Surveying and Mapping Beijing 100039 China

chinese Area Positioning System (CAPS) is a transmitted satellite navigation system moved by the chinese academy of sciences. Three basic modes of navigation and positioning with CAPS are given, and then a comparative analysis is made in this paper. In terms of the principle that the ionospheric delay is at an inverse ratio to the frequency square, a new ionospheric-free positioning method based on a double-antenna CAPS receiver is put forward. Then the hybrid differential observations and the solving equations and algorithms for one epoch and multi epochs are deduced according to the basic principle of the method. The method may remove the global errors in signal emission, propagation, transmission and receiving (e.g., ionospheric delay, hardware delay, and clock error). So it is very convenient for the single-epoch solution and multi-epoch navigation and positioning, and may efficiently improve the precision of real time CAPS navigation. Furthermore, the method can be used not only for the geometric orbit determination of CAPS GEO and IGSO satellites and the navigation and positioning, but also for the estimation of the tropospheric zenith delay, which is useful for the study of water vapor changes in the atmosphere. Polynomials are used in this method to express the tropospheric zenith delay and CAPS satellite orbits within the limited time interval, which reduces the num- ber of unknown parameters and thus speeds the computation.

关键词： chinese Area Positioning System (CAPS) ionospheric-free linear combination double-antenna receiver hybrid differential positioning method