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Acta geologica Sinica(English Edition) 1993年第4期67卷 387-402页

作者： ge ningjie, li shuguang, peng zhonghua and liu deliang department of earth and space sciences, university of Science and {4. of china, hefei, anhui jiang minxi department of earth and space sciences University of Science and Technology of China Hefei Anhui

There are obvious differences in the mineral assemblage and metamorphic P-T conditions between the eclogites from the northern and southern parts of the eastern Dabie Mountains. Those from the northern part of the mountains are developed in Alpine peridotite and gneiss. They have a mineral assemblage of garnet+diopside with no quartz, and were formed at temperatures of 600℃-74.℃. Those from the southern part are developed in gneiss and marble. They consist of garnet+omphacite+less quartz and were metamorphosed at temperatures in the range of 650°-800℃. These differences suggest that the former may be formed during the metamorphism of the deep subducted oceanic crust, whereas the latter may be genetically related to the subduction of the continental crust in this area.

关键词： collisional orogen eclogitic rocks from the southern and northern parts of the Dabie Mountains T-P conditions

Seasonal compensation implied no weakening of the land carbon sink in the Northern Hemisphere under the 2015/2016 El Niño

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Science china earth sciences 2024年第1期67卷 281-294页

作者： Fangzhong SHI Xiuchen WU Xiaoyan li Philippe CIAIS Hongyan liu Chao YUE Yuting YANG Shulei ZHANG Shushi peng Yi YIN Benjamin POULTER {4. CHEN State Key Laboratory of earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Faculty of geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation Qinghai Normal UniversityXining 810016China Research and Development Center for Watershed Environmental Eco-Engineering Beijing Normal University(Zhuhai)Zhuhai 519085China Laboratoire des sciences du Climat et de l’Environnement(LSCE) CEA-CNRS-UVSQUMR821291191Gif-sur-YvetteFrance College of Urban and Environmental Science MOE Laboratory for Earth Surface ProcessesPeking UniversityBeijing 100871China State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) School of Atmospheric SciencesSun Yat-sen UniversityGuangzhou 510275China California Institute of technology PasadenaCA 91125USA Biospheric sciences Laboratory NASA Goddard Space Flight CenterGreenbeltMaryland 20771USA Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg SE-40530Sweden

The recurrent extreme El Niño events are commonly linked to reduced vegetation growth and the land carbon sink over many but discrete regions of the Northern Hemisphere(NH).However,we reported here a pervasive and continuous vegetation greening and no weakened land carbon sink in the maturation phase of the 2015/2016 El Niño event over the NH(mainly in the extra-tropics),based on multiple evidences from remote sensing observations,global ecosystem model simulations and atmospheric CO_(2)*** discovered a significant compensation effect of the enhanced vegetation growth in spring on subsequent summer/autumn vegetation growth that sustained vegetation greening and led to a slight increase in the land carbon sink over the spring and summer of 2015(average increases of 23.34.and 0.63%in net ecosystem exchange from two independent datasets relative to a 5-years average before the El Niño event,respectively)and spring of 2016(6.82%),especially in the extra-tropics of the NH,where the water supply during the pre-growing-season(November of the previous year to March of the current year)had a positive *** seasonal compensation effect was much stronger than that in 1997 and 1998 and significantly alleviated the adverse impacts of the 2015/2016 El Niño event on vegetation growth during its maturation *** legacy effect of water supply during the pre-growing-season on subsequent vegetation growth lasted up to approximately six *** findings highlight the role of seasonal compensation effects on mediating the land carbon sink in response to episodic extreme El Niño events.

关键词： El Niño Seasonal compensation effect Vegetation greening Land carbon sink Net ecosystem exchange Legacy effect

Discovery and analysis of ultra-micro grinding grain texture in slipping lamellae of ductile-brittle zone

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Science china earth sciences 2004年第3期47卷 265-271页

作者： ge Heping1, SUN Yan1, LU Xiancai1, ZHU Wenbin1, GUO Jichun1, liu deliang2 & Chi-yuen Wang3 1. department of {4. sciences, Nanjing university, State Key Laboratory of Mineral Deposit, Nanjing 210093, china 2. department of {4. and space sciences, university of Science and technology of china, hefei 230026, china 3. department of geology and geophysics, university of California, Berkeley, CA 94.20, USA Nanjing Univ Dept Earth Sci State Key Lab Mineral Deposit Nanjing 210093 Peoples R China Univ Sci & Technol china Dept Earth & Space Sci Hefei 230026 Peoples R China Univ Calif Berkeley Dept Geol & Geophys Berkeley CA 94720 USA

Based on the observation of the deep bore cores sampled from the State of Cali-fornia, USA, preferred arranged particulate concentration belts were found in the ultra-slipping lamellae. And the same phenomenon was found again later in the bore cores from the petroleum basin in the Northern Shaanxi Province. It may be the product of the dynamic processes involv-ing tumbling, grinding and compresso-shearing functions, so the spherical particulates with ul-tra-size of nm and mm are called grinding grain. The formation of the grinding grains is related with the ductile-brittle deformation, the lateral pressure of the slipping, and the very low grade of dynamic metamorphism of the rocks. Based on the systematic analysis, it is indicated that some elements like Nb and Ta are enriched in the grinding grains in the granitic rocks because of the chemical differentiation, and that the slipping lamellae bearing grinding grains in mudstone with smear efficiency prove a perfect seal for oil and gas reservoirs. Meanwhile, the paper provides bases for the studies on the fast stick-slip movement and shear paradigm.

关键词： slipping lamellae, grinding grain texture, ductile-brittle deformation, smear efficiency.

HiFAST:An HIdata calibration and imaging pipeline for FAST

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Science china(Physics,Mechanics & Astronomy) 2024年第5期67卷 182-199页

作者： Yingjie Jing Jie Wang Chen Xu Ziming liu Qingze Chen Tiantian liang Jinlong Xu Yixian Cao Jing Wang Huijie Hu Chuan-peng Zhang Qi Guo liang Gao Mei Ai Hengqian Gan Xuyang Gao Jinlin Han ligang Hou Zhipeng Hou peng jiang Xu Kong Fujia li Zerui liu li Shao Hengxing Pan Jun Pan Lei Qian Jinghai Sun Ningyu Tang Qingliang Yang Bo Zhang Zhiyu Zhang Ming Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 02206China School of Astronomy and space Science University of Chinese Academy of SciencesBeijing 100049China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 55000China Max Planck Institute for Extraterrestrial Physics Garching 85748Germany Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Institute of Computational Cosmology Department of PhysicsUniversity of DurhamDurham DHI 3LEUK CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Deep space Exploration Laboratory/department of Astronomy University of Science and Technology of ChinaHefei 230026China School of Astronomy and space Science University of Science and Technology of ChinaHefei 230026China Astrophysics Department of PhysicsUniversity of OxfordOxford OX/3RHUK College of earth sciences Guilin University of TechnologyGuilin 541004China department of Physics Anhui Normal UniversityWuhu 241002China School of Astronomy and space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 20023China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST)has the largest aperture and a 19-beam L-band receiver,making it powerful for investigating the neutral hydrogen atomic gas(HI)in the *** present HiFAST(https://***),a dedicated,modular,and self-contained calibration and imaging pipeline for processing the H?data of *** pipeline consists of frequency-dependent noise diode calibration,baseline fitting,standing wave removal using an FFT-based method,flux density calibration,stray radiation correction,and gridding to produce data *** modules can be combined as needed to process the data from most FAST observation modes:tracking,drift scanning,On-The-Fly mapping,and most of their *** HiFAST,the root-mean-square(RMS)noises of the calibrated spectra from all 19 beams were only slightly(~5%)higher than the theoretical *** results for the extended source M33 and the point sources are consistent with the results from *** moment maps(0,1 and 2)of M33 agree well with the results from the Arecibo Galaxy Environment Survey(AgeS)with a fractional difference of less than 10%.For a common sample of 221 sources with signal-to-noise ratio S/N>10 from the Arecibo Legacy Fast ALFA(ALFALFA)survey,the mean value of fractional difference in the integrated flux density,Sint,between the two datasets is approximately 0.005%,with a dispersion of 15.4..Further checks on the integrated flux density of 23 sources with seven observations indicate that the variance in the flux density of the source with luminous objects(Sint>2.5 Jy km s-1)is less than 5%.Our tests suggest that the FAST telescope,with the efficient,precise,and user-friendly pipeline HiFAST,will yield numerous significant scientific findings in the investigation of the H?in the universe.

关键词： fractional luminous correction

Coronal Magnetic Flux Rope Equilibria and Magnetic Helicity

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Chinese Journal of Astronomy and Astrophysics 2001年第1期1卷 77-84页

作者： You－QinHu Yan－Weijiang 等 departmentofearthandspaceScience UniversityofScienceandTechnologyofChinaHefei230026 departmentofEart

Using a 2.5-dimensional (2.5-D) ideal MHD model, this paper analyzes the equilibrium properties of coronal magnetic flux ropes in a bipolar ambient magnetic field. It is found that the geometrical features of the magnetic flux rope, including the height of the rope axis, the half-width of the ropes and the length of the vertical current sheet below the ropes are determined by a single magnetic parameter, the magnetic helicity, which is the sum of the self-helicity of the rope and the mutual helicity between the rope field and the ambient magnetic field. All the geometrical parameters increase monotonically with increasing magnetic helicity. The implication of this result in solar active phenomena is briefly discussed.

关键词： Sun: magnetic fields - Sun: magnetic flux rope - Sun: magnetic helicity

HiFAST:An H?data calibration and imaging pipeline for FAST

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Science china(Physics,Mechanics & Astronomy) 2024年第5期Mechanics & Astronomy) .卷 186-203页

作者： Yingjie Jing Jie Wang Chen Xu Ziming liu Qingze Chen Tiantian liang Jinlong Xu Yixian Cao Jing Wang Huijie Hu Chuan-peng Zhang Qi Guo liang Gao Mei Ai Hengqian Gan Xuyang Gao Jinlin Han ligang Hou Zhipeng Hou peng jiang Xu Kong Fujia li Zerui liu li Shao Hengxing Pan Jun Pan Lei Qian Jinghai Sun Ningyu Tang Qingliang Yang Bo Zhang Zhiyu Zhang Ming Zhu National Astronomical Observatories Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University School of Astronomy and space Science University of Chinese Academy of Sciences Guizhou Radio Astronomical Observatory Guizhou University Max Planck Institute for Extraterrestrial Physics Kavli Institute for Astronomy and Astrophysics Peking University Institute of Computational Cosmology Department of PhysicsUniversity of Durham CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of Sciences Deep space Exploration Laboratory/department of Astronomy University of Science and Technology of China School of Astronomy and space Science University of Science and Technology of China Astrophysics Department of PhysicsUniversity of Oxford College of earth sciences Guilin University of Technology department of Physics Anhui Normal University School of Astronomy and space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing University

The Five-hundred-meter Aperture Spherical radio Telescope（FAST） has the largest aperture and a 19-beam L-band receiver,making it powerful for investigating the neutral hydrogen atomic gas（H?） in the *** present HiFAST（https://***）,a dedicated,modular,and self-contained calibration and imaging pipeline for processing the H?data of *** pipeline consists of frequency-dependent noise diode calibration,baseline fitting,standing wave removal using an FFT-based method,flux density calibration,stray radiation correction,and gridding to produce data *** modules can be combined as needed to process the data from most FAST observation modes:tracking,drift scanning,On-The-Fly mapping,and most of their *** HiFAST,the root-mean-square（RMS） noises of the calibrated spectra from all 19 beams were only slightly（～5%） higher than the theoretical *** results for the extended source M33 and the point sources are consistent with the results from *** moment maps（0,1 and 2） of M33 agree well with the results from the Arecibo Galaxy Environment Survey（AgeS） with a fractional difference of less than 10%.For a common sample of 221 sources with signal-to-noise ratio S/N>10 from the Arecibo Legacy Fast ALFA（ALFALFA） survey,the mean value of fractional difference in the integrated flux density,Sint,between the two datasets is approximately 0.005%,with a dispersion of 15.4..Further checks on the integrated flux density of 23 sources with seven observations indicate that the variance in the flux density of the source with luminous objects(Sint>2.5 Jy km s-1) is less than 5%.Our tests suggest that the FAST telescope,with the efficient,precise,and user-friendly pipeline HiFAST,will yield numerous significant scientific findings in the investigation of the H? in the universe.

关键词：

Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 571-578页

作者： liu QingHui1, CHEN Ming1, XIONG WeiMing2, QIAN ZhiHan1, li Jinling1, HAO WangHong1,4. WANG Guangli1, ZHENG WeiMin1, GUAN Di3, ZHU RenJie1, WANG WeiHua1, ZHANG XiuZhong1, {4. DongRong1, SHU FengChun1, PING JinSong1 & HONG XiaoYu11 Shanghai Astronomical Observatory, Chinese Academy of sciences, Shanghai 200030, china 2 Center for space Science and Applied Research, Chinese Academy of sciences, Beijing 100190, china 3 Lunar Explorer Engineering general department, Chinese Academy of sciences, Beijing 100012, china 4.Beijing Institute of Tracking and Telecommunications technology, Beijing 100094. china 1. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China2. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China4. Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China3. Lunar Explorer Engineering General Department Chinese Academy of Sciences Beijing 100012 China

Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four Chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.

关键词： same-beam VLBI differential phase delay relative position determination lunar rover

A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor

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Research in Astronomy and Astrophysics 2024年第10期24卷 25-35页

作者： Yi Zhao Wangchen Xue Shaolin Xiong Qi Luo Yuanhao Wang Jiacong liu Heng Yu Xiaoyun Zhao Yue Huang Jinyuan liao Jianchao Sun Xiaobo li Qibin Yi Ce Cai Shuo Xiao Shenglun Xie Chao Zheng Yanqiu Zhang Chenwei Wang Wenjun Tan Zhiwei Guo Chaoyang li Zhenghua An Gang Chen Yanqi Du Min Gao Ke Gong Dongya Guo jiang He Jianjian He Bing li Gang li Xinqiao li Jing liang Xiaohua liang Yaqing liu Xiang Ma Rui Qiao liming Song Xinying Song Xilei Sun Jin Wang Ping Wang Xiangyang Wen Hong Wu Yanbing Xu Sheng Yang Dali Zhang Fan Zhang Hongmei Zhang {14. Zhang Shu Zhang Zhen Zhang Shijie Zheng Keke Zhang Xingbo Han Haiyan Wu Hu Tai Hao geng Gao{14. Lu Wei Xu Fanchao Lyu Hongbo Zhang Fangjun Lu Shuangnan Zhang department of Astronomy Beijing Normal UniversityBeijing 100875China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of sciences Beijing 100049China School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China College of Physics Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Institute of Astrophysics Central China Normal UniversityWuhan 430079China College of physics sciences technology Hebei UniversityBaoding 071002China Physics and space Science College China West Normal UniversityNanchong 637002China School of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China College of Electronic and information Engineering Tongji UniversityShanghai 201804China Innovation Academy for Microsatellites of Chinese Academy of sciences Shanghai 201304China National space Science Center Chinese Academy of SciencesBeijing 100190China School of earth and space sciences University of Science and Technology of ChinaHefei 230026China Electronic Information School Wuhan UniversityWuhan 430072China Key Laboratory of Transportation Meteorology of china Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210000China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up *** based on the relative counts of different detectors has been widely used for all-sky gamma-ray *** are two major methods for this count distribution localization:χ^(2)minimization method and the Bayesian *** we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^(2)*** comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^(2)method,especially for weak *** further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location *** method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations.

关键词： methods:data analysis methods:analytical (stars:)gamma-ray burst:general

Calculation of the CO2 Degassing during Contact Metamorphism and Its geological Significance:The Model and Example from the Shuanshan Area of the South Tan-Lu Fault Belt

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Acta geologica Sinica(English Edition) 2008年第3期82卷 562-576页

作者： YANG Xiaoyong liu deliang CHEN Yongjian DAI Jinxing CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi＇an 710069 China The Institute of Research and Exploration for Oil and Natural Gas China ChiefOil and Natural Gas Corporation Beijing 100083 China

The paper studies CO2 degassing and controlling factors under the condition of contact metamorphism in the Shuangshan area, southern Tan-Lu fault belt and the method of calculating the amount of CO2 degassing. The results show that the amount of CO2 degassing is controlled by the characteristics of the country rocks, including the thermal conductivity, penetrability, porosity and connectivity. Compositions, size and depth of intrusive rock also have an important influence on CO2 degassing, i.e., they generated numerous cracks in the country rocks, and thus allowed the easy flow and accumulation of fluids. The amount of CO2 flux in contact metamorphism is calculated quantitatively based on the metamorphic reaction and time-integrated fluid flux. The value （0.729- 2.4.6×10^4.mol/cm^2） of CO2 flux suggests that CO2 was provided mainly by the contact metamorphic reaction. The generation and releasing of CO2 are positively correlated with the degree of metamorphism, and XCO2 in fluids gradually increases from dolomite zone to calcite zone, but in the zone of grossular, fluid flux is the largest and XCO2 sharply decreases due to involvement of magmatic water. This study presents evidence that a large amount of industrial-scale CO2 can be produced during contact metamorphism. On the basis of theoretical and practical studies, a cone model has been proposed to response CO2 degassing for the contact metamorphism, and it can be used to explore CO2 accumulations beyond the oil-gas basins. This model can also be applied to the study of inorganic genesis of CO2 accumulations.

关键词： Contact metamorphism CO2 degassing CO2 accumulations Tan-Lu fault belt

Precise orbit determination of Haiyang‑2D using onboard BDS‑3 B1C/B2a observations with ambiguity resolution

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Satellite Navigation 2023年第3期4卷 167-184页

作者： Kecai jiang Wenwen li Min li jianghui {4.ng Haixia Lyu Qile Zhao Jingnan liu GNSS Research Center Wuhan University129 Luoyu RoadWuhan 430079China Key Laboratory of space Ocean Remote Sensing and Application Ministry of Natural Resources8 Dahui Temple RoadBeijing 10081China Collaborative Innovation Center of geospatial technology 129 Luoyu RoadWuhan 430079China department of Land Surveying and geo‑Informatics The Hong Kong Polytechnic University11 Yuk Choi RoadHung HomKowloonHong KongChina

The Haiyang-2D altimetry mission of china is one of the first Low earth Orbit(LEO)satellites that can receive new B1C/B2a signals from the BeiDou-3 Navigation Satellite System(BDS-3)for Precise Orbit Determination(POD).In this work,the achievable accuracy of the single-receiver ambiguity resolution for onboard LEO satellites is studied based on the real measurements of new BDS-3 *** normal conditions,six BDS-3 satellites on average are ***,the multipath of the B1C/B2a code observations presents some patchy patterns that cause near-field variations with an amplitude of approximately 4. cm and deteriorate the ambiguity-fixed *** modeling those errors,for the B2a code,a remarkable reduction of 53%in the Root Mean Square(RMS)is achieved at high elevations,along with an increase of 8%in the ambiguity-fixed ***,an analysis of the onboard antenna’s phase center offsets reveals that when compared to the solutions with float ambiguities,the estimated values in the antenna’s Z direction in the solutions with fixed ambiguities are notably *** independent validation of the resulting POD using satellite laser ranging at 16 selected high-performance stations shows that the residuals are reduced by a minimum of 15.4.for ambiguity-fixed solutions with an RMS consistency of approximately 2.2 ***,when compared to the DORIS-derived orbits,a 4.3 cm 3D RMS consistency is achieved for the BDS-3-derived orbits,and the along-track bias is reduced from 2.9 to 0.4.cm using ambiguity fixing.

关键词： Ambiguity resolution B1C/B2a Onboard BDS-3 Precise orbit determination Haiyang-2D