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Science china Earth sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3, WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. department of Earth sciences, State Key Laboratory of Mineral Deposit Research,{2., nanjing 2.0093. china 2. Center of Materials Analysis,{2., nanjing 2.0093. china 3. department of Environmental Science and Engineering,{2., nanjing 2.0093. china 4. Beijing Geology Institute, Nuclear Industry, Beijing 10002., china nanjing university Nuclear Industry

The first results of sorption experiments of U(VI), 2.4U(VI) and 2.8U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 2.4U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural Science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1,2. Ge Yuhui1, Cai Yuanfeng2.and Zhang Xuefeng3(1. Faculty of resources & Environment, Southwest Petroleum university, Chengdu 610500, {2. 2. State Key Laboratory for Endogenic Metal Deposit Research, nanjing university, nanjing 2.0093. china 3. department of Natural resources & Technology Information, {2. university of Petroleum, Beijing 102.49, {2.) Faculty of resources and Environment Southwest Petroleum University Chengdu 610500 China State Key Laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China department of Natural resources and Technology Information China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 32.℃, suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 30 h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

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. {2. of Earth Science, nanjing university, nanjing 2.0093. china Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences Guiyang China department of Earth Science Nanjing University Nanjing Chin

The interaction between peat, lignite and germanium(Ge)-bearing solution with an initial Ge concentration of 5 mg/L was studied at 2.―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 4

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

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,{2. 2. Shanghai Observatory, Chinese Academy of sciences, Shanghai 2.0030, china 3. Physics department, nanjing Normal university, nanjing 2.0097, 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 1994-07-2., 2. 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.

A study on dynamical features of air-sea coupling waves in the tropics

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Acta Oceanologica Sinica 1993年第3期12卷 379-393页

作者： Yang Xiuqun and Huang Shisong department of Atmospheric sciences,{2., nanjing 2.0008, china

The dynamical features of air-sea coupling waves and their stabilities in a simple coupled air-sea model in the tropics have been studied with respect to interaction occurring among different types of the free waves in the o-cean and in the atmosphere. It is pointed out that there exist a stable and an unstable air-sea interaction modes in the tropical coupled system , respectively. The propagation of the unstable mode relies greatly on the zonal space scale, i. e. only for wave length ranging from 5 000 km to 10 000 km can the disturbance unstably move slowly eastward. The waves that slowly propagate unstably eastward agree well with the observational facts. Finally,it is also proposed that the interaction between Kelvin wave in one medium and Rossby wave in another medium is a necessary condition for the occurrence of destabilization of the coupled air-sea system in the tropics.

关键词： Air-sea interaction coupling waves features

Binomial coefficients,Catalan numbers and Lucas quotients

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Science china Mathematics 2010年第9期53卷 2473-2488页

作者： SUN ZhiWei department of Mathematics,nanjing {2.,nanjing 2.0093.china department of Mathematics Nanjing University Nanjing China

Let p be an odd prime and let a,m ∈ Z with a > 0 and p ︱ *** this paper we determinep ∑k=0 pa-1(2. k=d)/mk mod p2.for d=0,1;for example,where(-) is the Jacobi symbol and {un}n≥0 is the Lucas sequence given by u0 = 0,u1 = 1 and un+1 =(m-2.un-un-1(n = 1,2.3,...).As an application,we determine ∑02.for any integer r,where Ck denotes the Catalan number 2.k /(k + 1).We also pose some related conjectures.

关键词： congruences binomial coefficients Catalan numbers Lucas quotients

Magnetic fabrics in fault-related fold and its relation with finite strain: an example from Mingjiang thrust structures in Western Sichuan

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Progress in Natural Science:Materials International 2007年第5期17卷 551-558页

作者： Jia Dong, Chen Zhuxin, Luo Liang, Hu Qianwei and Jia Qiupeng (department of Earth sciences,{2., nanjing 2.0093. china) department of Earth sciences Nanjing University Nanjing 210093 China

The anisotropy of magnetic susceptibility (AMS) is a quick, effective and sensitive technique used to measure the weakly deformed sedimentary rocks, and also a reliable method to reveal the deforming mechanisms of fault-related folds. In Longmenshan front belt, a typical cross-section of fault-related folds is chosen to study the AMS. A total of 2.4 oriented specimens have been drilled at 2. different sampling sites which were distributed at the key structural positions of this structural section developed in the Xujiahe formation of the upper Triassic. Six elementary types of magnetic fabrics are recognized and established through this AMS study: Da sedimentary fabric; 2. an initial deformation fabric; 3) a pencil structure fabric; 4) a weak cleavage fabric; 5) a strong cleavage fabric; 6) a stretching lineation fabric. It has been found that most of magnetic fabrics are characterized by fabrics of weak deformation which belong to the pure-shear results of a pre-folding layer parallel shortening (LPS). In the fault-bend fold, almost all magnetic fabrics are the initial deformation fabrics of weak deformation, and denote that the deformation in the forelimb is stronger than that in the backlimb and no finite strain is shown in the footwall. While in the fault-propagation fold, finite strains are concentrated in the trishear zone where magnetic fabric results are approximately consistent with the estimated consequences of the kinematic model. The tectonic stress field indicated by the magnetic fabrics is basically the same along the whole structural section and shows a NW to SE compression and shortening which is accordant with the regional compressive stress field of the Longmenshan fold-thrust belt.

关键词： magnetic fabric finite strain fault-related fold trishear zone Longmenshan.

An Accurate Rate Control Algorithm for Mobile Wireless Channel

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china Communications 2009年第1期6卷 119-122页

作者： Ma Guoqiang1 , Bi Houjie2.1nanjing university,{2. 2.0} university of Posts and Telecommunications,{2. nanjing university Nanjing 210093 China nanjing university of Posts and Telecommunications Nanjing 210093 China

A novel rate control algorithm for extremely low bit rate and wireless channels is specified in this paper. The algorithm does rate analysis at an MB (Macro Block) level, and extracts the energy from motion and texture characteristics, finally allocates bits and controls the fluctuation according to the MB energy. Experimental results show that a higher accuracy of allocation of bit rate is achieved and the output bit rate is much smoother, as well as the improvement of subjective quality is considerable.

关键词： rate control low bitrate wireless channel video coding

On contactomorphism group of contact structure overtwisted at infinity on R^3

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Science china Mathematics 2007年第8期50卷 1087-1092页

作者： Li YU department of Mathematics,nanjing {2.,nanjing 2.0093.china department of Mathematics Nanjing University Nanjing China

We compute all the homotopy groups of the compactly supported contactomorphism group of a contact structure on R^3 which is overtwisted at infinity.

关键词： contactomorphism overtwisted contact structure

Potash-rich volcanic rocks and lamprophyres in western Shandong Province:^(40)Ar-^(39)Ar dating and source tracing

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Chinese Science Bulletin 2002年第2期47卷 91-99页

作者： QIU Jiansheng, XU Xisheng & LO Ching-HuaState Key Laboratory of Mineral Deposit Research of nanjing university, nanjing 2.0093. china {2. of Earth sciences, nanjing university, nanjing 2.0093. china {2. of Geology, Taiwan Unive State Key Laboratory of Mineral Deposit Research of nanjing university Nanjing China department of Earth sciences Nanjing University Nanjing China department of Geology Taiwan University Taibei China

Highly precise 40Ar-39Ar dating results demon-strate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7-12..3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (87Sr/86Sr)i ratios ( 0.708715-0.711418) and distinctly negative εNd values ( -11.47--17.54), and are enriched in radiogenic lead (2.6Pb/2.4Pb=17.341-17.62., 2.7Pb/2.4Pb=15.52.-15.538, 2.8Pb/2.4Pb=37.563-37.684). Similarly, the lamprophyres also have quite low εNd values (-11.57 - -19.64). Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings, and extensive comparisons of the Sr, Nd isotopic composi-tions with that of the related simultaneous rocks, it is con-cluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting

关键词： potash-rich volcanic rocks lamprophyres 40Ar-39Ar dating Sr-Nd-Pb isotope tracing western Shandong Province.