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Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, china: Implication for ore genesis

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Science china Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1,2.& PAN Guitang2.1. Geoscience college, Chengdu university of Technology, Chengdu 610059, {2. 2. Chengdu Institute of Geology and Mineral Resources, Chengdu 610082. {2. 1. Geoscience college Chengdu University of Technology Chengdu 610059 China 2. Chengdu Institute of Geology and Mineral Resources Chengdu 610082 China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, china. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in china. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

Architecture and application of integrated spatial information service platform for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1, XIAO Jie2.1. college of Mining, Taiyuan university of Technology, Taiyuan 03002., {2. 2. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, {2. Taiyuan Univ Technol Coll Min Taiyuan 030024 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote sensing data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2.& XU WeiSheng 2.1 college of Hydraulic and Environmental Engineering,china Three Gorges {2.,Yichang 443002.china 2.college of Hydropower Engineering,Xi’an {2. of Technology,Xi’an 710048,china 1. college of Hydraulic and Environmental Engineering China Three Gorges University Yichang 443002 China2. College of Hydropower Engineering Xi’an University of Technology Xi’an 710048 China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

A new orthogonality relationship for orthotropic thin plate theory and its variational principle

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1 , LONG Yuqiu 2.& LIU Guangdong 1 1. college of Civil Engineering, Hunan university, Changsha 410082. {2. 2. Department of Civil Engineering, Tsinghua university, Beijing 100084, {2. 1. college of Civil Engineering Hunan University 410082 Changsha China 2. Department of Civil Engineering Tsinghua University 100084 Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Empirical likelihood confidence regions of the parameters in a partially linear single-index model

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Science china Mathematics 2005年第10期48卷 1333-1348页

作者： XUE Liugen~1 & ZHU Lixing~2.1. college of Applied Sciences,Beijing university of Technology,Beijing 10002.,{2. 2. Department of Mathematics,Hong Kong Baptist university,Hong Kong,{2. 1. college of Applied Sciences Beijing University of Technology 100022 Beijing China 2. Department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, a partially linear single-index model is investigated, and three empirical log-likelihood ratio statistics for the unknown parameters in the model are suggested. It is proved that the proposed statistics are asymptotically standard chi-square under some suitable conditions, and hence can be used to construct the confidence regions of the parameters. Our methods can also deal with the confidence region construction for the index in the pure single-index model. A simulation study indicates that, in terms of coverage probabilities and average areas of the confidence regions, the proposed methods perform better than the least-squares method.

关键词： partially linear single-index model, empirical likelihood, confidence region, chi-square distribution, coverage probability.

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural Science:Materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. Department of Mathematics, Beijing Normal university, Beijing 100875, china 2. Department of Mathematics, Neijiang Teacher's {2., Neijiang 641112. china) Beijing Normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators

Diffusion and Oxidation Wear of PCBN Tool based on Thermodynamics

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 265-271页

作者：邵芳 Binzhou Vacational college School of Mechanical Engineering Shandong University

The rules of diffusion wear and oxidation wear for PCBN cutting tools were analyzed based on thermodynamics theory. Dissolution concentrations in typical normal workpice materials of PCBN tool material at different temperature were then calculated. Diffusion reaction rules in high temperature were developed and analyzed using the Gibbs free energy criterion. The machining tests were conducted using the PCBN tools at different cutting speeds of 50, 95,100 and 180 m/min, feed of 0.1, 0.2.and depth of cut of 0.1, 0.8, 1, and 1.5 mm respectively on a PUMA300LM numerically-controlled lathe. It was found that the theoretical results were uniform with the experimental data, and the results will provide useful references for tool material design and selection.

关键词： thermodynamics PCBN tool diffusion wear oxidation wear

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. college of Atmospheric Sciences, Lanzhou university, Lanzhou 730000, {2. 2. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., {2.) college of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2.Zhao-Feng JIANG~2. 1 college of Life Science,Capital Normal university,Beijing 100037,{2. 2.college of Applied Sciences and Humanities,Beijing Union university,Beijing 100083,{2. college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied Sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2.and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure