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Chinese science Bulletin 2007年第7期52卷 936-941页

作者： shi rendeng1,2 1 school of earth and space sciences, university of science and technology of china, hefei 23.026, china 2 Institute of Geology, Chinese Academy of Geological sciences, Beijing 100037, china (email: shird@***) school of earth and space sciences University of Science and Technology of China Hefei 230026 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The SHRIMP U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12, MSWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.

关键词：西藏班公湖怒江缝合带古海洋闭合时期 SSZ型蛇绿岩 SHRIMP 测年

Application of rock creep experiment in calculating the viscoelastic parameters of earth medium

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science china earth sciences 2006年第5期49卷 492-498页

作者： shi Xingjue1, WEN Dan1, BAO Xueyang1, LI Chengbo1 & HUANG Yun2 1. school of earth and space sciences, university of science and technology of china, hefei 23.026, china 2. Seismological Bureau of Jiangsu Province, Nanjing 210014, china school of earth and space sciences University of Science and Technology of China Hefei China Seismological Bureau of Jiangsu Province Nanjing China

Based on the rock creep experiment, the data of aftershock sequence and post-earth- quake deformation are used to estimate the viscosity of crust medium near earthquake focus. Firstly 9 samples that belong to 3 kinds of rock are conducted in creep experiment under constant pressure to obtain the creep curves directly. Inversion results show that the standard linear model is the best one to present the earth medium. It exhibits obvious elasticity within a short time, while it exhibits obvious rheology within a long time. The relationship between element module μ 2 and the whole module μ of standard linear model or the module of real earth medium is calculated and analyzed. On the basis of μ 2 = 25 μ, the sequence of aftershock of Gonghe earthquake in Qinghai Province is analyzed and the relationship between accumulated released strain and the time is obtained, which, combined with the creep experiment results, is used to estimate the viscosity of crustal medium in this area. The measured vertical deformation after the same earthquake also is combined with the creep experiment results, then it is used to calculate the relaxation time and viscosity through three different methods respectively, i.e. inversion of Kelvin model, difference method of deformation and viscoelastic dislo- cation theory. The viscosity of crustal medium in 32 km depth of earthquake focus of Gonghe area deduced from the different data and methods is about 1019 Pa·s, which is the same as the research results by other authors at home and abroad.

关键词： creep experiment, aftershock sequence, post-earthquake deformation, crustal viscosity.

Experimental study of the relationship between fluid density and saturation and sonic wave velocity of rock samples from the WXS Depression,South china Sea

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Petroleum science 2011年第1期8卷 43-48页

作者： Pei Fagen Zou Changchun He Tao Pan Lingzhi Xiao Kun shi Ge Ren Keying Key Laboratory of Geo-detection（china university of Geosciences Beijing）Ministry of EducationBeijing 100083 China school of earth and space sciences Peking UniversityBeijing 100871China Zhanjiang Branch of china National Offshore Oil Corporation Ltd. Guangdong 524057China

The relationship between fluid density and saturation and sonic wave velocity of rock samples taken from the WXS Depression in the South china Sea was studied by an oil-water replacement experiment under simulated in-situ temperature and pressure *** kinds of low-density oils（0.691 and 0.749 g/cm^3） and two kinds of high-density oils（0.834 and 0.873 g/cm^3） were used to saturate the rock samples at different oil-saturation states,and the saturated P- and S-wave velocities were *** Gassmann＇s equation,the theoretical P- and S-wave velocities were also calculated by the fluid replacement *** the comparison of the measured values and the theoretical values, this study comes to the following conclusions.（1） With the increase of oil saturation and the decrease of water saturation,the P-wave velocity of rock samples saturated by low-density oil increases and the changing rule is in accord with the effective fluid theory;the P-wave velocity of rock samples saturated by high-density oil decreases and the changing rule goes against the theory.（2） With the increase of oil density（namely 0.691→0.749→0.834→0.873 g/cm^3） when oil saturation is unchanged,P-wave velocity increases gradually.（3） The S-wave velocity is always stable and is not affected by the change of oil density and *** results can be used to constrain pre-stack seismic inversion,and the variation rule of sonic wave velocity is valuable for hydrocarbon identification in the study area.

关键词： Rock physics saturation compressional wave shear wave water drive Gassmann's equation fluid replacement

Promoted surface charge density from interlayer Zn–N_(4) configuration in carbon nitride for enhanced CO_(2) photoreduction

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Nano Research 2024年第4期17卷 2400-2409页

作者： Xianjin shi Yu Huang Gangqiang Zhu Wei Peng Meijuan Chen State Key Laboratory of Loess and Quaternary Geology(SKLLQG) Key Laboratory of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center of Excellence in Quaternary science and Global Change Chinese Academy of SciencesXi’an 710061China university of Chinese Academy of sciences Beijing 100049China school of Physics and Information technology Shaanxi Normal UniversityXi’an 710062China school of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China

The solar-driven reduction of CO_(2) into valuable products is a promising method to alleviate global environmental problems and energy ***,the low surface charge density limits the photocatalytic conversion performance of CO_(2).Herein,a polymeric carbon nitride(PCN)photocatalyst with Zn single atoms(Zn1/CN)was designed and synthesized for CO_(2) *** results of the CO_(2) photoreduction studies show that the CO and CH_(4) yields of Zn1/CN increased fivefold,reaching 76.9 and 22.9μmol/(g·h),respectively,in contrast to the unmodified ***+plasma-etched X-ray photoelectron spectroscopy and synchrotron radiation-based X-ray absorption fine structure results reveal that Zn single atom is mainly present in the interlayer space of PCN in the Zn–N_(4) *** characterizations indicate that the interlayer Zn–N_(4) configuration can amplify light absorption and establish an interlayer charge transfer ***-assisted Kelvin probe force microscopy confirms that more photogenerated electrons are delivered to the catalyst surface through interlayer Zn–N_(4) configuration,which increases its surface charge ***,in-situ infrared spectroscopy combined with density functional theory calculation reveals that promoted surface charge density accelerates key intermediates(*COOH)conversion,thus achieving efficient CO_(2) *** work elucidates the role of internal single atoms in catalytic surface reactions,which provides important implications for the design of single-atom catalysts.

关键词： single-atom catalysts photocatalytic CO_(2)reduction interlayer modification charge transfer dynamics surface charge density

Distribution, bioaccumulation, trophic transfer and risk assessment of trace elements in fish from a typical shallow outflow lake basin, china

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Frontiers of Environmental science & Engineering 2024年第7期18卷 141-156页

作者： Miao He Guijian Liu Xiaodan shi Lei Wu Qiang Chen CAS Key Laboratory of Crust-Mantle Materials and Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Anhui Academy of Environmental sciences Hefei 230022China school of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China

Fish are important food sources for humans,and the availability of appropriate amount of trace elements(TEs)plays a crucial role in fish ***,due to large volumes of sewage discharge,high levels of certain elements are present in aquatic environments,and these elements accumulate in fish and potentially affect human *** this study,the distribution and bioaccumulation capacity of trace elements in six dominant fish species from Chaohu Lake(china)were *** results showed that the bioaccumulation capacity of fish for Zn was greater than other *** the source of the TEs in the fish were explored along with the concentration of the TEs in the aquatic environment,which indicated that TEs in fish were mainly obtained through ingestion and indirectly affected by the industrial activities in the ***,stable carbon and nitrogen isotopes were used to classify the trophic levels and explore the biological magnification of TEs of the *** was found that Sb and Sr showed biomagnification with the increase of trophic level of *** on the above analyses,the environmental biogeochemical cycle model of TEs in the lake was distinguished and established,which can offer valuable insights for sustainable fishery management in the downstream Yangtze River Delta ecosystem.

关键词： Trophic level Bioaccumulation Risk assessment Trace elements

Simulation study of the performance of the Very Large Area gamma-ray space Telescope

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Nuclear science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan Wei Jiang Chuan Yue shi-Jun Lei Yu-Xin Cui Qiang Yuan Key Laboratory of Dark Matter and space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China school of Astronomy and space science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

The Review of Land Use/Land Cover Mapping AI Methodology and Application in the Era of Remote Sensing Big Data

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Journal of Geodesy and Geoinformation science 2024年第3期7卷 1-23页

作者： ZHANG Xinchang shi Qian SUN Ying HUANG Jianfeng HE Da College of Geography and Remote Sensing sciences Xinjiang UniversityUrumqi 830017China school of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006China school of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China school of Atmospheric sciences Sun Yat-sen UniversityZhuhai 519082China

With the increasing number of remote sensing satellites,the diversification of observation modals,and the continuous advancement of artificial intelligence algorithms,historically opportunities have been brought to the applications of earth observation and information retrieval,including climate change monitoring,natural resource investigation,ecological environment protection,and territorial space *** the past decade,artificial intelligence technology represented by deep learning has made significant contributions to the field of earth ***,this review will focus on the bottlenecks and development process of using deep learning methods for land use/land cover mapping of the earth’s ***,it introduces the basic framework of semantic segmentation network models for land use/land cover ***,we summarize the development of semantic segmentation models in geographical field,focusing on spatial and semantic feature extraction,context relationship perception,multi-scale effects modelling,and the transferability of models under geographical ***,the application of semantic segmentation models in agricultural management,building boundary extraction,single tree segmentation and inter-species classification are ***,we discuss the future development prospects of deep learning technology in the context of remote sensing big data.

关键词： remote sensing big data deep learning semantic segmentation land use/land cover mapping

Plasma and magnetic field characteristics of magnetic holes in the solar wind at 1AU: Cluster observations

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Plasma and magnetic field characteristics of magnetic holes ...

Re-Os isotope geochemistry of three Chinese chondrites

第十四届全国日地空间物理学术研讨会

作者： T. Xiao1 Q.Q. shi1 Z.Y. Pu2 S.Y. Fu2 Q-G. Zong2 W.J. Sun1 (1 school of space science and Physics, Shandong university at Weihai, Weihai, china ) (2 Institute of space Physics and Applied technology, Peking university, Beijing, china )

Magnetic holes （MHs） are structures observed in interplanetary space with significant decrease in the magnetic field magnitude and with no or little change in the field direction. In this work, we have analyzed the magnetic field and plasma properties around the MHs and made comparisons with the average solar wind. It is found that the MHs occur in relatively lower magnetic field regions, and higher ion density regions, and higher plasma beta regions. We also investigated the MHs which located in the interplanetary coronal mass ejections （ICME） or the sheath of the ICME near-earth. It is found that there are relatively more MHs associated with ICMEs during the solar maximum. So it may infer that the ICME is one source for the LMHs during the solar maximum. However, the occurrence rates of MHs in the solar wind have no significant change from the year 2001 to 2010, which suggests that the sources other than ICME may contribute more to LMHs generated during the solar minimum.

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Chinese science Bulletin 2007年第16期52卷 2269-2274页

作者： ZHI XiaChen QIN Xie shi rendeng HONG JiAn CAS Key Laboratory of Crust-Mantle Material and Environment School of Earth and Space Sciences University of Science andTechnology of China Hefei 230026 China

Three Chinese ordinary chondrites,including Jilin (H5),Boxian (LL3.8) and Lujiang (LL6),have been studied for their Re and Os abundances and Os isotopic composition in whole-chondrite samples,separated magnetic and nonmagnetic fractions,and nodules. The results indicate that the Re and Os abundances of the whole-chondrite samples are in the ranges of corresponding H-and LL-Groups,respectively. The Re and Os abundances of magnetic fraction from Boxian and Lujiang are within the range of high-Os ⅡAB and ⅢAB irons,whereas those of nonmagnetic fractions of Boxian and Lujiang are lower than the whole-chondrite values. The Re and Os abundances of nodules in Jilin are in the range of the LL-Group. 187Re/188Os and 187Os/188Os ratios of the three whole chondrites are in the range of ordinary chondrites which locate around the isochron of ⅡAB+ⅢAB irons. 187Re/188Os and 187Os/188Os ratios of the magnetic and nonmagnetic fractions from Boxian have a larger difference. The nonmag-netic fraction of Lujiang may contain a recent addition of Re,which causes deviation of the 187Re/188Os ratio from the irons isochron. The Re and Os abundances of nodules in Jilin are lower than those of the whole-chondrite,but their 187Os/188Os ratios are higher than that of the whole chondrite.

关键词：球粒状陨石铼锇同位素地球化学中国

Effects of coal-fired power plants on soil microbial diversity and community structures

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Journal of Environmental sciences 2024年第3期137卷 206-223页

作者： Bowen Sun Renbin Zhu Yu shi Wanying Zhang Zeming Zhou Dawei Ma Runfang Wang Haitao Dai Chenshuai Che Institute of Polar Environment&Anhui Key Laboratory of Polar Environment and Global Change School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 450046China State Grid Anhui Electric Power Research Institute Hefei 230601China

Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power ***,the effects of coal-fired power plants on soil microbial communities have received little attention through atmospheric pollutant deposition and ***,we collected the samples of power plant soils(PS),coal-stacking soils(CSS)and agricultural soils(AS)around three coal-fired power plants and background control soils(BG)in Huainan,a typical mineral resource-based city in East china,and investigated the microbial diversity and community structures through a high-throughput sequencing ***-stacking significantly increased(pships between soil microbial communities and long-term disturbances from coal-fired power plants.

关键词： Coal-fired power plants Soil microbial communities Coal-stacking Heavy metals Environmental variables