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微体古生物学报 2001年第2期 193-198页

作者： CHEN Zhe and SUN Wei guo (nanjing Institute of Geology and palaeontology,{2.,{3.)

Numerical simulations of magnetic reconnection in the lower solar atmosphere

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Research in Astronomy and Astrophysics 2011年第2期11卷 225-236页

作者： Xiao-Yan Xu 1,2.Cheng Fang 2.Ming-De Ding 2.and Dan-Hui Gao 2.1 Purple Mountain Observatory,{4. academy of Science,{2. {3.,China 2.Department of Astronomy,{2. University,{2. 2.0093.China Purple Mountain Observatory Chinese Academy of Science Nanjing 210008 China Department of Astronomy Nanjing University Nanjing 210093 China

Observations indicate that Ellerman bombs （EBs） and chromospheric microflares both occur in the lower solar atmosphere,and share many common features,such as temperature enhancements,accompanying jet-like mass motions,short life-time,and so *** strongly suggest that EBs and chromospheric microflares could both probably be induced by magnetic reconnection in the lower solar *** gravity,ionization and radiation considered,we perform two-dimensional numerical simulations of magnetic reconnection in the lower solar *** influence of different parameters,such as intensity of the magnetic field and anomalous resistivity,on the results are *** result demonstrates that the temperature increases are mainly due to the joule dissipation caused by magnetic *** spectral profiles of EBs and chromospheric microflares are calculated with the non-LTE radiative transfer theory and compared with *** is found that the typical features of the two phenomena can be qualitatively reproduced.

关键词： Sun: chromosphere-- Sun: photosphere -- Sun: magnetic reconnection-- Sun: numerical simulation

Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3.into carbonate

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Science China Earth sciences 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2. LI HuaLing1,3. LIU WeiGuo4. WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai Institute of Salt Lakes, chinese academy of sciences, Xining 810008, China 2.State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. China 3.{2. Institute of Geology and Mineral Resources, {2. 2.0016, China 4.State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075, China 5 State Key Laboratory for Mineral Deposits Research, Department of Earth sciences, {2. University, {2. 2.0093. China 1. Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China 2. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China 3. nanjing Institute of Geology and Mineral Resources 210016 Nanjing China 4. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.3.0}was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3. between carbonate and B(OH)3.in seawater range 0.93. and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3.values between carbonate and B(OH)3.in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4.pH curves and neither do they exactly parallel any theoretical δ 11B4.pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3.with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4. in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4.3. between B(OH)4. and B(OH)3.is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

Palaeogene fossil Populus leaves from Lanzhou Basin and their palaeoclimatic significance

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chinese Science Bulletin 2004年第14期49卷 1494-1501页

作者： SUN Bainian1,2. YAN Defei1, XIE Sanping1, CONG Peiyun1, XIN Cunlin1 & YUN Fei1 1. Key Laboratory of Western China抯 Environmental Systems of the Ministry of Education, Lanzhou University, Lanzhou 73.000, China 2. State Key Laboratory of Palaeobiology and Stratigraphy, nanjing Institute of Geology and {3., {2. {3. of Sci-ences, nanjing 2.0008, China Key Laboratory of Western China''s Environmental Systems of the Ministry of Education Lanzhou University Lanzhou 730000 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontolog Chinese Academy of Sci- ences Nanjing 210008 China

An angiosperm compression flora is found in Palaeogene from Lanzhou Basin and the cuticular analysis of Populus davidiana Dode in the flora is carefully made. Fur-thermore, the fossil cuticles are compared with the epidermal structures of extant Populus leaves growing in different en-vironments, i.e. moist, semimoist, and semiarid to arid cli-matic regions. The present experiments indicate that mature leaves of P. davidiana show leaf size from big to small, leaf cuticles from thick to thin and anticlinal walls of epidermal cells from faintness to clarity along with the increase of lati-tudes of the plant distributions, the climatic variation from moist to arid, the annual precipitation from more to less and the annual mean temperature from high to low. The fossil P. davidiana differs from the specimens collected from Shandan in semiarid to arid climatic regions but closely resembles the Wushan leaves in a semi-moist climatic area in a lot of fea-tures. In a word, the new research may reflect that the flora lives in a semi-moist climatic environment. The present dis-covery of compression of Paleogene Populus davidiana is of great significance to studying vegetation types, climatic and environmental changes during the primal uplifting of the Qinghai-Tibet Plateau.

关键词：古气候兰州盆地山杨化石角质层早第三纪被子植物

INTRODUCTION TO FOSSIL ALGAE AND STROMATOLITES

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微体古生物学报 2003年第1期 2-4页

作者： MU Xinan 1,2. YUAN Xunlai 1 1 nanjing Institute of Geology and palaeontology,{2.,{4.2.State Key Laboratory of Palaeobiology and Stratigraphy,{4.

Jianshangou Bed of the Yixian Formation in West Liaoning, China

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Science China Earth sciences 2005年第3期48卷 298-312页

作者： CHEN Peiji1,2. WANG Qifei1, ZHANG Haichun1,2. CAO Meizhen1, LI Wenben1, WU Shunqing1 & SHEN Yanbin1 1. nanjing Institute of Geology and Palaeontolgoy,{3.,{2., China 2. State Key Laboratory of Palaeobiology and Stratigraphy,{2., China 1. nanjing Institute of Geology and Palaeontolgoy Chinese Academy of Sciences 210008 Nanjing China 2. State Key Laboratory of Palaeobiology and Stratigraphy 210008 Nanjing China

The Jianshangou Bed is a set of fossil-bearing sedimentary interlayers of the basal volcano-sedimentary deposits of Yixian Formation in western Liaoning. It is rich in volcanic composition and consists of upper and lower grey-black shale, basal sandy conglomerate, top tuffaceous sandstone, middle massive silty mudstone and siltstone, as well as andesite, with a thickness of 2.—95 m. The Jianshangou Bed is famous all over the world for its bearing early birds, angiosperms and feathered dinosaurs, and it also yields bivalves, gastropods, con- chostracans, ostracods, shrimps, insects, fish, amphibians, primitive mammals and other reptiles. These fossils are typical representatives of the Late Mesozoic Jehol Biota from eastern Asia. The Chaomidianzi and Sihetun formations, proposed in recent years, are regarded as the junior synonyms of the Jianshangou Bed. The Jehol Biota is endemic to eastern Asia, however, it has a large geographic distribution, more than half of the European territory. Many species of the biota have close relationships with the late Jurassic European counterparts, e.g. both Confuciusornis and Archaeopteryx are primitive birds, Sinosauropteryx has a similar skeleton construction with Compsognathus, the ostracode assemblage from the Jianshangou Bed is close to that from the Purbeck Bed in England, and Aeschnidium occurs in both the Jianshangou Bed and Solnhofen of Germany. Based on the biostratigraphic correlation, the Jianshangou Bed is more probably late Tithonian in age. The latest zircon U-Pb dating of the Jianshangou Bed gives 12..2.Ma, and is close to the feldspar Ar/Ar dating of 12..6 Ma. A glauconite dating of 12. Ma was once got from England near the J/K boundary within the Purbeck Bed, so it is still problematic to place the J/K boundary at 13., 13., 13., 14.0}or 14..5 Ma in the International Stratigraphic Charts.

关键词： Yixian Formation, Jianshangou Bed, Jehol Biota, J/K Boundary.

Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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Science China Earth sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1,2. MA Dongsheng2. BAO Zhengyu3. PAN Jiayong2. CAO Shuanglin2.& XIA Fei2.1. School of Mathematics and Physics, China University of Geosciences, Wuhan 4.0074. China 2. State Key Laboratory for Research of Mineral Deposits, nanjing University, nanjing 2.0093. China 3. Faculty of Earth sciences, China University of Geosciences, Wuhan 4.0074. China 1. School of Mathematics and Physics China University of Geosciences Wuhan 430074 China 2. State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China 3. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, China, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2.0.4.m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.

On the knee of Galactic cosmic rays in light of sub-TeV spectral hardenings

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chinese Physics C 2018年第7期42卷 113-122页

作者： Yi-Qing Guo1 2.Qiang Yuan1 3.1. Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory chinese academy of {2. {4. 2.0008 China 2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China

More than fifty years after the discovery of the knee in the cosmic ray （CR） spectra, its physical origin remains a mystery. This is partly due to the ambiguity of the energy spectra of individual components. Recently, direct measurements from several space experiments found significant spectral hardenings of CR nuclei at ~2.0 GV. A joint modeling of the direct and indirect measurements may help to understand the experimental systematics and the physics of the knee. In this work, we update the phenomenological ＂poly-gonato＂ model to include the spectral hardenings, with a changing spectral index of γ ＋ β·logE. This modification gives a reasonable description of the CR spectra in a wide energy range. However, the fits to different data sets give different results. We find that the fit to the AMS-02.and CREAM data slightly favors a relatively low energy knee of the light components. In such a case, the expected all-particle spectra under-shoot the data, which may require an extra component of CRs. The fits to AMS-02.data and the light component （H＋He） data from the Tibet ASγ/ARGO-YBJ/WFCTA and KASCADE experiments give consistent results with the all-particle spectra. We further propose a possible physical realization of such a ＂modified poly-gonato＂ model of spectral hardenings by means of spatially-dependent diffusion of CRs. We find reasonably good agreement between the model predictions and the data for CR spectra, the secondary-to-primary ratios, and the amplitude of anisotropies.

关键词： cosmic ray knee spectrum propagation

3. virtual reconstruction of the Pleistocene cheetah skull from the Tangshan, nanjing, China

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Progress in Natural Science:Materials International 2007年第1期17卷 74-79页

作者： DONG Wei, HOU Xinwen, LIU Jinyi, FANG Yingsan, JIN Changzhu and ZHU Qizhi ( Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, Beijing 10004., China State Key Laboratory of Pattern Recognition, Institute of Automation, chinese academy of sciences, Beijing 100080, China {{3. Provincial Museum, {{3. {3.0016, China Radiology Department, Renmin Hospital, Peking University, Beijing 10004., China) [a]Institute of Vertebrate Paleontology and Palecanthropology Chinese Academy of Sciences Beijing China [b]State Key Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing China [c]nanjing Provincial Museum Nanjing China [d]Radiology Department Renmin Hospital Peking University Beijing China

The development of computer tomography and image processing has made it possible to establish virtual 3. reconstruction and non-invasive dissection of fossil specimens. We used these methods to reconstruct a virtual 3. skull of a Pleistocene cheetah skull from the Tuozi cave, Tangshan, nanjing, and virtually dissected it for anatomic studies, and measured the volumes of different parts of the endocranium. The endocranium of the cheetah skull has showed that its frontal sinus is beehive-like, the frontal lobe of cerebra is relatively large but the temporal lobe is relatively small, its cerebral sulcus and gyrus are more complicated than those of the domestic cat, similar to those of the domestic dog, but simpler than those of giant panda, pig, cattle and horse. The technology of virtual 3. reconstruction and non-invasive dissection of fossil specimens can extend the morphological study from the exterior to the interior, and it can also help to study fragile specimens and virtually backup rare and precious specimens.

关键词： CT imaging 3. reconstruction cheetah skull early Pleistocene Tangshan nanjing.

Autonomous satellite constellation orbit determination using the star sensor and inter-satellite links data

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Science China(Physics,Mechanics & Astronomy) 2010年第5期53卷 966-974页

作者： GAN QingBo1,2.MA JianBo1 & XU Jin1 1 Purple Mountain Observatory,chinese academy of {2.,{4. 2.0008,China 2.Graduate University of chinese academy of sciences,Beijing 10004.,China 1. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

A method of autonomous orbit determination for a satellite constellation using a star sensor combined with inter satellite links(ISLs) is *** types of simulated observation data,Three-Satellite Constellation ISLs and background stellar observations by a CCD star sensor,are first *** on these data,an observation equation is built for the constellation joint autonomous orbit determination,in which the simulations are *** accuracy of this method with different orbital determination models are analyzed and compared with regard to the effect of potential measurement *** results show that autonomous satellite constellation orbit determination using star sensor measurement and ISLs data is ***,this paper arrives at several conclusions which contribute to extending this method to a more general satellite constellation.

关键词： satellite constellation star sensor inter-satellite links autonomous orbit determination