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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 61.500,{1. 2. State Key Laboratory for Endogenic Metal Deposit Research, Nanjing university, Nanjing 2.0}093.{1. 3. Department of Natural Resources & Technology Information,{1. university of Petroleum, Beijing 1.2.49,{1.) Faculty of Resources & Environment Southwest Petroleum University Chengdu 610500 China State Key Laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China Department of Natural Resources & 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 3.0}℃, suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 3. 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.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1.2.3.& WANG Huijun2.1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 1.002., china 2. Department of Atmospheric Science, Yunnan {1., Kunming 650091. china 3. Graduate {1. of the Chinese Academy of Sciences, Beijing 1.0049, china 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate university of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1.3. SUN Weiguo1.2.& FENG Hao1.1. Institute of Physics, Sichuan university, Chengdu 61.065,{1. 2. College of Chemical Engineering, Sichuan university, Chengdu 61.065,{1. 3. Mianyang Teacher抯 College, Mianyang 62.0}00,{1. Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) 1. Institute of Physics Sichuan University 610065 Chengdu China 2. Mianyang Teacher's College 621000 Mianyang China 3. College of Chemical Engineering Sichuan University 610065 Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2. state of CO+, the X2. g + state of Li 2.+ , the X2. g + state of He 2.+ , the 1.∏u state of Na 2.+ , the A2.u state of N 2.+ , the X1.+ state of KrH+, the X2.+ state of SiO+ and the A2. state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.

Cotton pixel identification with CBERS-02.CCD data based on spectral knowledge

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Science china(Technological Sciences) 2005年第S2期48卷 129-144页

作者： LI Jing1.2.3. LIU Qinhuo1.3. LIU Qiang1. CHEN Liangfu1. BO Junhua3.& LI Shaokun3.1. State Key Laboratory of Remote Sensing Science, IRSA, Chinese Academy of Sciences, Beijing 1.01.1. china 2. Graduate {1. of Chinese Academy of Sciences, Beijing 1.0049, china 3. The Key Oasis Eco-agriculture Laboratory of {12. Production and Construction Corps, Shi Hezi 83.1}00, china 1. State Key Laboratory of Remote Sensing Science IRSA Chinese Academy of Sciences 100101 Beijing China 2. Graduate university of Chinese Academy of Sciences 100049 Beijing China 3. The Key Oasis Eco-agriculture Laboratory of xinjiang Production and Construction Corps 832000 Shi Hezi China

In this paper the in-situ experiment data are collected from the Spectral Library to estimate the possible values of the primary structural parameters in each cotton growing season by statistics. Based on these values the spectra of the cotton major growing seasons were simulated and analyzed using the canopy reflectance model, SAILH. In this way we also simulated the cotton pixel spectra corresponding to CBERS-02.CCD and took them as the reference spectra for spectra fitting. Then No.1.3.Regiment of No.8 Agricultural Division of xinjiang Production and Construction Corps (XPCC) was chosen as the study area, and two spectra fitting methods, Mahalanobis distance and spectra angle, were used to identify cotton pixel from CBERS-02.CCD image of the study area. At last we analyzed the effect of the calibration coefficients error on cotton identifying. The results showed that within 4% error the spectral angle classifier can still have a good performance.

关键词： CBERS-02 cotton pixel identification spectra fitting.

Effect of an impurity on 3.electron quantum dots in magnetic fields

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 521-530页

作者： LIU Yimin1.2. HUANG Gangming1.& BAO Chengguang1.1. Department of Physics, Zhongshan university, Guangzhou 51.2.5,{1. 2. Department of Physics, Shaoguan university, Shaoguan 51.005,{1. 1. Department of Physics Zhongshan University 510275 Guangzhou China 2. Department of Physics Shaoguan University 512005 Shaoguan China

The ground-state property of a 2.dimensional 3.electron quantum dot (QD) subjected to an external magnetic fieldB and affected by an impurity is studied. The impurity is located at thez-axis by a distanced from the plane of the dot. The evolution of the angular momentumL o and the spinS o of the ground state in accordance withB andd has been calculated, and the results are summarized and plotted in a (L o,S o) diagram. The spatial distribution of the electrons (the size and the geometric features) and the optical absorption have also been investigated. The (L o S o) diagram indicates thatL o andS o may jump whend and/orB vary. It was found that, due to the constraints arising from symmetry, each symmetric geometry is accessible only to a specific group of states having specificL o andS o.

关键词： quantum dot, ground state, charged impurity, magnetic field.

Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt

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Science china Earth Sciences 2005年第5期48卷 585-600页

作者： YANG Wencai 1., YANG Wuyang 1., JIN Zhenmin 2.& CHENG Zhenyan 1.1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 1.003., china 2. china {2. of Geosciences, Wuhan 43.074, china 1. Chinese Academy of Geological Sciences Institute of Geology 100037 Beijing China 2. china {1. of Geosciences 430074 Wuhan China

Calibration of seismic reflectors appearing in the crust of the Chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 1. km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supe

关键词： deep seismic reflection, ultrahigh-pressure belt, Sulu china, calibration of reflectors, lithospheric fabrics.

Population-size-dependent branching processes in Markovian random environments

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Chinese Science Bulletin 1998年第8期43卷 635-638页

作者： WANG Hanxing 1.and DAI Yonglong 2.1. Department of Mathematics, Shanghai {2., Shanghai 2.1.00,{1. 2. Department of Mathematics, Zhongshan {2., Guangzhou 51.2.5,{1. Department of Mathematics Shanghai University Shanghai China Department of Mathematics Zhongshan University Gunngzhou China

A branching model {Z n} n≥0is considered where the offspring distribution of the population’s evolution is not only dependent on the population size, but also controlled by a Markovian environmental process {ξ n} n≥0. For this model, asymptotic behaviour is studied such as limn→∞Z n and limn→∞Z n/m n in the case that the mean m k, θof the offspring distribution converges to m>1.as the population size k grows to ∞. In the case that {ξ n} n≥0is an irreducible positive recurrent Markov chain, certain extinction (i.e. P(Z n=0 for some n)=1. and noncertain extinction (i.e. P(Z n=0 for some n)1. are studied.

关键词： Markov chains in random environments stochastic population models branching processes.

The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological Sciences) 2004年第z1期47卷 118-126页

作者： JIANG Xiaohui1. LIU Changming1.2. WANG Yu3.& WANG Hongrui1.1. Beijing Normal university, Beijing 1.0875,{1. 2. Institute of Geographic Science and Natural Resources, Chinese Academy of Sciences, Beijing 1.01.1.{1. 3. Reconnaissance, Planning, Design and Research Institute, YRCC, Zhengzhou 450003.{1. Beijing Normal Univ Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China YRCC Reconnaissance Planning Design & Res Inst Zhengzhou 450003 Peoples R China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1. When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 1.%; when precipitation decreases by 1.%, the average annual runoff will decrease by 8.{3.; when precipitation is steady, the average annual runoff will decrease by {3.4% if temperature increases 1.; if temperature decreases 1., runoff will increase by 1.{3.. The mix regression model can well simulate annual runoff. ({3. As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1. and precipitation decreases by 1.%. Under this condition, the simulated average annual runoff decreases by 1..8%. On the contrary, scenario 1.is the best to the enhancement of runoff; i.e. when temperature decreases 1.℃ precipitation will increase by 1.%, which will make the annual runoff of Sanmenxia increase by 1..6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

Prediction of Tumor Outcome Based on Gene Expression Data

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Wuhan university Journal of Natural Sciences 2004年第2期9卷 177-182页

作者： Liu Juan 1.2. Hitoshi Iba 3.1. School of Computer, Wuhan {2., Wuhan 43.072. Hubei,{1. 2. State Key Laboratory of Software Engineering, Wuhan 43.072. Hubei,{1. 3. Department of Frontier Informatics, {2. of Tokyo, Tokyo 1.3.8656, Japan Wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) university of Tokyo Department of Frontier Informatics Tokyo Japan (GRID:grid.26999.3d) (ISNI:***)

Gene expression microarray data can be used to classify tumor types. We proposed a new procedure to classify human tumor samples based on microarray gene expressions by using a hybrid supervised learning method called MOEA+WV (Multi-Objective Evolutionary Algorithm+Weighted Voting). MOEA is used to search for a relatively few subsets of informative genes from the high-dimensional gene space, and WV is used as a classification tool. This new method has been applied to predicate the subtypes of lymphoma and outcomes of medulloblastoma. The results are relatively accurate and meaningful compared to those from other methods. Key words bioinformatics - tumor classification - Pareto optimization - MOEA CLC number Q 786 - TP 1.1.Foundation item: Supported by the National Natural Science Foundation of{2. (603.1.09), the Foundation of Young Scholars of Ministry of Education of{2. (1.01.8) and Chenguang Project of Wuhan City (2.0}1.1.09).Biography: Liu Juan (1.70-), female, Associate Professor, Postdoctoral, research direction: bioinformatics, data mining, machine learning.

关键词： bioinformatics tumor classification Pareto optimization MOEA