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Thermal-rheological structure of the lithosphere beneath Jiyang Depression:Its implications for geodynamics

Science china earth sciences 2005年第10期48卷 1569-1584页

作者： LIU Shaowen1,2, WANG Liangshu2, GONG Yuling2, LI Cheng2, LI Hua2 & HAN Yongbing2 1. department of Urban and Resources, nanjing university, nanjing 210093, china 2. department of earth sciences, nanjing university, nanjing 210093, china department of Urban and Resources nanjing university nanjing china department of earth sciences nanjing university nanjing china

Jiyang Depression, located in the southeast Bohai Bay Basin, has the geomorpho-logic framework of multiple uplifts intervening with sags. Combined the abundant geo-temperature data and thermo-physical parameters of rock samples derived from oil and gas exploration during the past years, with geothermal approaches, here we investigate the litho-spheric thermal regime of this depression. Consequently, based on the obtained thermal struc-ture of the lithosphere, along with rheological modeling, the lithospheric rheological profiles of Jiyang Depression are then determined. Our results show that the temperature at the bottom of sedimentary cover within depression varies from 129℃ to 298 ℃ , accompanied with the base-ment heat flow ranging between 54.3 and 60.5 mW/m2; and 406℃-436℃ for temperature at the bottom of the upper crust, along with heat flow varying from 47.7 to 52.6 mW/m2; while the tem-perature at the bottom of the middle crust is between 537 ℃ and 572 ℃, as well as heat flow ranging from 41.3 to 56.3 mW/m2. The temperature at Moho ranges from 669 ℃ to 721 ℃, the heat flow derived from mantle is between 38.1 and 43.1 mW/m2, and calculated thickness of the thermal lithosphere beneath depression varies from 71 to 90 km. Lithospheric thermal regime is a close correlation with such factors as crustal thickness and surface heat flow, etc. Usually, the larger the surface heat flow, the larger the deep temperature and heat flow within lithosphere, and the thinner the thermal lithospheric thickness. This high thermal regime of the lithosphere in Jiyang Depression is thought to be related to Cenozoic back-arc spreading during the western Pacific plate subduction into Eurasian continent. Lithospheric rheological modeling shows that the lithosphere in Jiyang Depression is characterized by its distinct rheological stratification as follows: The upper and most part of the middle crust are of brittle, while the lower crust and the lower part of middle crust are all ductile

关键词： Jiyang Depression, geothermics, rheology, effective elastic thickness, geodynamics.

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Time of impact of fragment P2 of comet SL 9 on Jupiter

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Chinese Science Bulletin 1997年第5期42卷 396-398页

作者： ZHOU Hongnan,QIAN Bochen, HUANG Keliang and LI Qibin1. department of Astronomy, nanjing university, nanjing 210093, china 2. Shanghai Observatory, Chinese Academy of sciences, Shanghai 200030, china 3. Physics department, nanjing Normal university, nanjing 210097, china 4. Beijing Astronomical Observatory, Chinese Academy of sciences, Beijing 100080, china department of Astronomy Nanjing University Nanjing China Shanghai Observatory Chinese Academy of Sciences Shanghai China Physics department Nanjing Normal University Nanjing China Beijing Astronomical Observatory Chinese Academy of Sciences Behijing China

FROM 1994-07-16 to 1994-07-22, 21 fragments of comet SL 9 impacted against Jupiter in succession. During the impact period the impact of fragments D, E, K, N, P2 and S was observed in china. We used a 1.56-m telescope with the CCD camera of Shanghai Observatory to monitor Jupiter and its Galilean Satellites, obtaining 1000 high-quality images at B, V, I wave bands. Our data on optical wave bands are rather complete and valuable in the world. Specially, we got some images of Jupiter, Io and Europa in the impact time of fragment P2 impacting against Jupiter. This will help us understand the precise time, position, depth and energy of the P2’s collision. In this note, we report the impact time of fragment P2 of comet SL 9 and Jupiter. Since the impact of comet SL 9 was expected to take place on the side of Jupiter

关键词： comet comet Shoemaker-Levy 9 impacting against Jupiter impact time.

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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 earth sciences, nanjing university, State Key Laboratory of Mineral Deposit, nanjing 210093, china 2. department of earth and Space sciences, university of Science and Technology of china, Hefei 230026, china 3. department of Geology and Geophysics, university of California, Berkeley, CA 94720, 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.

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Statistical properties for the vibrational energy levels of OCS

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Chinese Science Bulletin 2002年第8期47卷 641-643页

作者： XIE Daiqian & LU YuhuiInstitute of Theoretical and Computational Chemistry, department of Chemistry, nanjing university, nanjing 210093, china department of Chemistry, Sichuan university, Chengdu 610064, china Institute of Theoretical and Computational Chemistry Department of Chemistry Nanjing University Nanjing China department of Chemistry Sichuan University Chengdu China

A potential energy surface for the electronic ground state of carbonyl sulfide was optimized by using a self-consistent configuration-interaction method and involving the recently observed vibrational band origins up to 8000 cm-1. With the optimized potential, the vibrational energy levels of OCS up to 15000 cm-1 were computed using the discrete variable representation method and Lanczos algorithm. Approximately 480 vibrational energy levels were identified. The statistical investigation showed that the vibrational energy levels of OCS up to 15000 cm-1 are largely regular.

关键词： OCS potential energy surface vibrational spectra sta-tistical property.

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A local spin evaluation into the active site models of [2Fe2S] ferrodoxin [Fe_2S_2(SR)_4]^(2-) (R=-H, -CH_3)

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Science china Chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2, WANG Yan3 & JU GuanZhi2,3 1 department of Chemistry, Hainan Normal university, Haikou 571158, china 2 State Key Laboratory of Theoretical and Computational Chemistry, Jilin university, Changchun 130023, china 3 department of Chemistry, nanjing university, nanjing 210093, china 1. department of Chemistry Hainan Normal University Haikou 571158 China 2. State Key Laboratory of Theoretical and Computational Chemistry Jilin University Changchun 130023 China 3. department of Chemistry Nanjing University Nanjing 210093 China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2S2(SR)4]2- (R=-H, -CH3) are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , , and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

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Velocity Space of Galactic O-B Stars

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Chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 363-371页

作者： Zi Zhu department of Astronomy Nanjing University Nanjing 210093

Based on the Hipparcos proper motions and available radial velocity data of O-B stars, we have re-examined the local kinematical structure of the young disk population of 1500 O-B stars not including the Gould-belt stars. A systematic warping motion of the stars about the direction to the Galactic center has been reconfirmed. A negative K-term implying a systematic contraction of stars in the solar vicinity has been detected. Two different distance scales are used in order to find out their impact on the kinematical parameters, and we conclude that the adopted distance scale plays an important role in characterizing the kinematical parameters at the present level of the measurement uncertainty.

关键词： astrometry - Galaxy: kinematics and dynamics - stars: early-type - Galaxy:solar neighborhood

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Wavelet estimation of the diffusion coefficient in time dependent diffusion models

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Science china Mathematics 2007年第11期50卷 1597-1610页

作者： Ping CHEN~(1,2+) Jin-de WANG~1 1 department of Mathematics,nanjing university,nanjing 210093,china 2 School of Science,nanjing university of Science and Technology,nanjing 210094,china department of Mathematics Nanjing University Nanjing 210093 China School of Science Nanjing University of Science Technology Nanjing 210094 China

The estimation problem for diffusion coefficients in diffusion processes has been studied in many papers,where the diffusion coefficient function is assumed to be a 1-dimensional bounded Lipschitzian function of the state or the time *** is no previous work for the nonparametric estimation of time-dependent diffusion models where the diffusion coefficient depends on both the state and the *** paper introduces and studies a wavelet estimation of the time-dependent diffusion coefficient under a more general assumption that the diffusion coefficient is a linear growth Lipschitz *** the properties of martingale,we translate the problems in diffusion into the nonparametric regression setting and give the Lr convergence rate.A strong consistency of the estimate is *** this result one can estimate the time-dependent diffusion coefficient using the same structure of the wavelet estimators under any equivalent probability *** example,in finance,the wavelet estimator is strongly consistent under the market probability measure as well as the risk neutral probability measure.

关键词： wavelet estimation time-dependent diffusion coefficient linear growth condition strong consistency

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Experimental study on the interaction between peat,lignite and germanium-bearing solution at low temperature

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Science china earth sciences 2005年第9期48卷 1411-1417页

作者： QI Huawen1,2, HU Ruizhong1 & QI Liang1 1. Key Laboratory of Ore Deposit Geochemistry, Chinese Academy of sciences, Guiyang 550002, china 2. department of earth Science, nanjing university, nanjing 210093, china 1. Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of earth Science Nanjing University 210093 Nanjing Chin

The interaction between peat, lignite and germanium(Ge)-bearing solution with an initial Ge concentration of 5 mg/L was studied at 25―100℃ and at pH 2.96―12.08. The results show that the apparent transfer ratios of peat and lignite for Ge in the solution were positively correlated with temperature in acid environment (initial pH=2.96), and the ratios (up to 86.5%) of lignite were obviously higher than those (up to 58.5%) of peat, but the organic transfer ratios of lignite were lower than those of peat. The activation energy values for interaction between peat, lignite and Ge-bearing solution are 30.96 and 15.67 kJmol?1, respectively. The strong acid (initial pH=2.96) and the strong alkaline (initial pH=12.08) environment contribute to the transfer of Ge in the solution. At 438) conduces to the transfer of Ge into lignite. The interaction between peat, lignite and Ge-bearing solution are mainly attributable for the complexation of Ge with organic substrate. The experimental results from this study provide direct experimental evidence for the hydrothermal sedimentary genesis of abnormal enrichment of Ge in coal.

关键词： low temperature, peat, lignite, Ge4+, complexation.

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STUDY ON THE FREQUENCY AND PRINCIPLE OF FLOOD CATASTROPHE IN THE CHANGJIANG DELTA AND ITS NEIGHBORING REGIONS IN THE LAST 2000 YEARS

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Chinese Geographical Science 2001年第2期11卷 137-143页

作者： ZHANG Sheng，ZHU Cheng，ZHANG Qiang (department of Urban and Resources sciences, nanjing university, nanjing 210093,P. R. china) department of Urban and Resources sciences Nanjing University Nanjing P. R. China

Documented materials, especially those about flooding catastrophe, are abundant comprehensive and well-preserved, which makes possible the systematical collection of materials about historical document about climate evolution in Changjiang (Yangtze) Delta region and its neighboring areas. We make good use of the exceptional information to discuss the genesis and principle of flooding in this region. Analysis shows that the main flooding periods in the studied region in the last 2000 years were the Western Jin Dynasty, Eastern Jin Dynasty, Northern and Southern Dynasties, Southern Song Dynasty, Yuan Dynasty, Ming Dynasty and Qing Dynasty. The periods with flooding peak values were the 4th century, 5th century, 7th century, 9th century, early 12th century, early 14th century, mid-15th century, and early 18th century A.D. Possibility of reappearance of flooding peak value in the early 21st century will be great, and the hazard prevention and the hazard reduction will be still hard.

关键词： Changjiang Delta historical flood frequently-occurred flood period flooding peak period

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Constraint on the counter-jet emission in gamma-ray burst afterglows from GRB 980703

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 259-261页

作者： WANG Xin,HUANG YongFeng & KONG SiWei department of Astronomy,nanjing university,nanjing 210093,china 1. department of Astronomy Nanjing University Nanjing 210093 China

We present a numerical investigation of emission from the receding jet of gamma-ray *** is found that the peak time of the receding jet emission is significantly affected by synchrotron self-absorption in radio ***,the receding jet component is generally very *** is observable mainly for those nearby events in a dense *** GRB 980703 has been observed in radio wavelengths for more than 1000 days,we argue that the receding jet emission still has not been detected for this ***,it is completely submerged by the host galaxy.

关键词： gamma rays:bursts ISM:jets and outflows methods:numerical

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