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Pathways of birnessite formation in alkali medium

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Science China Earth Sciences 2005年第9期48卷 1438-1451页

作者： FENG Xionghan1, TAN Wenfeng1, LIU Fan1, HUANG Qiaoyun1 & LIU Xiangwen2.1. College of Resources and Environment, Huazhong Agricultural university, wuhan 430070, China {2., China university of geosciences, wuhan 430074, China 1. College of Resources and Environment Huazhong Agricultural University 430070 Wuhan China 2. testing center China University of Geosciences 430074 Wuhan China

Birnessite is a common weathering and oxidation product of manganese-bearing rocks. An O2.oxidation procedure of Mn(OH)2.in the alkali medium has been used to synthesize birnessite. Fast and powder X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), energy dispersed X-ray analysis (EDAX), infrared spectroscopy (IR) techniques and chemical composition analysis, Eh-pH equilibrium diagram approaches were employed to investigate the reaction process and pathways of birnessite formation. Results showed that the process of the birnessite formation could be divided into four stages: (1) forma- tion stage for hausmannite and feitknechtite, (2. stage of transformation of hausmannite and feitknechtite to buserite, (3) buserite crystal growing stage, and (4) stage of conversion of buser- ite into birnessite. Mn(OH)2.was mainly present as amorphous state only for a short initial time of oxidation reaction. In the oxidation process, buserite formed following two pathways by recrys- tallization after dissolution of the intermediates, and the transformations of the minerals de- pended on the Eh determined by the dissolved O2.concentration on their surfaces. The results are fundamental in further exploration on the mechanism of birnessite formation in the alkali medium. A great practical significance would also be expected with respect to the areas of mate- rial sciences.

关键词： birnessite, pathway of formation, reaction process, Eh-pH diagram, hausmannite, feitknechtite.

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, China

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Science China Earth Sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3, QU Jing1 & ZHAO Wenxia4 1. Graduate School, China university of geosciences,{2., China 2. Test center, China university of geosciences,{2., China 3. Physics and Technology College, wuhan university, wuhan 430072. China 4. Test center, Zhongshan university, Guangzhou 5102.5, China China Univ Geosci Grad Sch Wuhan 430074 Peoples R China China Univ Geosci Test Ctr Wuhan 430074 Peoples R China wuhan Univ Phys & Technol Coll Wuhan 430072 Peoples R China Zhongshan Univ Test Ctr Guangzhou 510275 Peoples R China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, China have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463 nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3m and Fd3m, respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F4132. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

Seabed Classification Using BP Neural Network Based on GA

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Acta Oceanologica Sinica 2003年第4期22卷 523-531页

作者： Yang Fanlin1, Liu Jingnan2.1. GPS Engineering Research center, wuhan {2., wuhan 430079, China. 2. Presidential Secretariat, wuhan {2., wuhan 430079, China wuhan Univ GPS Engn Res Ctr Wuhan 430079 Peoples R China

Side scan sonar imaging is one of the advanced methods for seabed study. In order to be utilized in other projects, such as ocean engineering, the image needs to be classified according to the distributions of different classes of seabed materials. In this paper, seabed image is classified according to BP neural network, and. Genetic Algorithm is adopted in train network in this paper. The feature vectors are average intensity, six statistics of texture and two dimensions of fractal. It considers not only the spatial correlation between different pixels, but also the terrain coarseness. The texture is denoted by the statistics of the co-occurrence matrix. Double Blanket algorithm is used to calculate dimension. Because a uniform fractal may not be sufficient to describe a seafloor, two dimensions are calculated respectively by the upper blanket and the lower blanket. However, in sonar image, fractal has directivity, i. e. there are different dimensions in different direction. Dimensions are different in acrosstrack and alongtrack, so the average of four directions is used to solve this problem. Finally, the real data verify the algorithm. In this paper, one hidden layer including six nodes is adopted. The BP network is rapidly and accurately convergent through GA. Correct classification rate is 92.5 % in the result.

关键词： BP network co-occurrence matrix fractal classification genetic algorithin

Characteristics of the Bottom Boundary(T11) of Late Cretaceous Yaojia Formation in Songliao Basin and Its Dynamic Background

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地学前缘 2009年第S1期16卷 141-142页

作者： Ying Song~(1,2.,Jianye Ren~3,Huaizhong Yang~2.1.Key Laboratory of Tectonics and Petroleum Resources(China university of geosciences),Ministry of Education,{2. 430074,China. 2.Faculty of Earth Resources,China university of geosciences({2.),{2. 430074,China 3.Structural Research center of Oil&Gas Bearing Basin,Ministry of Education,Branch center in China university of geosciences,{2. 430074,China

Well-preserved Cretaceous lacustrine deposits in Songliao Basin NE China provide a unique oppor- tunity both for building the terrestrial type stage of Cretaceous in China and for studying the response of Cretaceous major global geological *** basin had undergone three stages of tectonic evolution during the Late Jurassic and Cretaceous:syn-rifting phase,post-rifting thermal subsidence phase and basin inversion *** shallow strata of Yaojia Formation contain excellent Putaohua and Sartu reservoir rocks,which contribute great to the giant

关键词： Songliao Basin tectonic inversion responding surface tectonic revolution

The Characteristics of the Bottom Boundary(T11) of Late Cretaceous Yaojia Formation in Songliao Basin and Its Dynamic Background

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地学前缘 2009年第S1期16卷 173-174页

作者： Ying Song~1,Jianye Ren~2.1.Faculty of Earth Resources,China university of geosciences,{2. 430074,China. 2.Structural Research center of Oil & Gas Bearing Basin,Ministry of Education,Branch center in China university of geosciences,{2. 430074,China

Well-preserved Cretaceous lacustrine deposits in Songliao Basin NE China provide a unique opportunity both for building the terrestrial type stage of Cretaceous in China and for studying the response of Cretaceous maj... 详细信息

关键词： Songliao Basin T11 boundary tectonic inversion responding surface tectonic revolution

Weathered Mantle Hosted Gold Deposit atShewushan, Hubei, Central China

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Journal of China university of geosciences 2001年第1期12卷 60-67页

作者： Hong Hanlie Wang Qinyan The center for Material Research and testing, {2. university of Technology, {2. 430070 Bian Qiujuan Faculty of Earth Sciences, China university of geosciences, wuhan 430074 The center for Material Research and testing Wuhan University of Technology Faculty of Earth Sciences China University of Geosciences

A supergene gold deposit is located at Shewushan, south Hubei, Central China. The Au mass fraction of the supergene deposits ranges from 1.0.10-6 to 19.5 10-6, with an average of about 2.2.10-6. Primary gold mineralization is closely associated with the well developed faults and fractures mainly on the crest of the reverse anticline with gold mass fraction exceeding1.0 X 10-6(average 0.6 X 10-6 ), the gold occurs as small Ag-bearing particles in association with illite and kaolinite, and partly incorporated within the lattice of pyrite. Fluid inclusion studies on the gold mineralization yield trapping temperatures and pressures from 110 to 2.0 and 410 105 to 460 105 pa, respectively. The salinities of mineralization fluids range from 2. 6 % to 8. 4 % w(NaCl, equivalent). Calculated (18O) values and measured (D) data of the hypogene fluids indicate a meteoric origin. These fluids underwent extreme 18 O enrichment by reacting with country carbonate rock. Supergene gold minerali- zation is confined largely to the lower portion at the weathered mantle; the gold occurs as small native gold particles accompanied by clay minerals, kaolinite and illite and Mn and Fe oxides. Geochemical investigation shows that Au, together with As and Sb, decreases progressively from the top of ore body to some 2.kilometers away and define a lateral dispersion halo. It is proposed that the gold is mobilized by surficial leaching and concentrated at the lower portion of the weathering profile, and thio-sulfate may play an active role in gold dissolution and re-precipitation.

关键词： gold deposit weathering inclusion temperature stable isotopes Shewushan.

Evaluation Method of Web Site Structure Based on Web Structure Mining

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wuhan university Journal of Natural Sciences 2003年第3A期8卷 791-796页

作者： Li Jun\|e 1 , Zhou Dong\|ru 2.1. Computer center,wuhan {2., wuhan 430072. Hubei, China 2. School of Computer,wuhan {2., wuhan 430072. Hubei,China wuhan university Computer Center Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The structure of Web site became more complex than before. During the design period of a Web site, the lack of model and method results in improper Web structure, which depend on the designer's experience. From the point of view of software engineering, every period in the software life must be evaluated before starting the next period's work. It is very important and essential to search relevant methods for evaluating Web structure before the site is completed. In this work, after studying the related work about the Web structure mining and analyzing the major structure mining methods (Page\|rank and Hub/Authority), a method based on the Page\|rank for Web structure evaluation in design stage is proposed. A Web structure modeling language WSML is designed, and the implement strategies for evaluating system of the Web site structure are given out. Web structure mining has being used mainly in search engines before. It is the first time to employ the Web structure mining technology to evaluate a Web structure in the design period of a Web site. It contributes to the formalization of the design documents for Web site and the improving of software engineering for large scale Web site, and the evaluating system is a practical tool for Web site construction.

关键词： web structure mining page\|rank web structure evaluation modeling language for web structure

Comprehensive evaluation of mechanism of "chimney effect" using principles of magnetism, geochemistry and mineralogy

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Chinese Science Bulletin 1998年第9期43卷 743-748页

作者： LIU Qingsheng 1, CHENG Tongjin 2.and LIU Shugen 3 1. Department of Applied Geophysics, China university of geosciences,{2., China 2. center of Petroleum Geochemistry, China National Star Petroleum Corporation, Hefei 2.002., China 3. The St Department of Applied Geophysics China University of Geosciences Wuhan China center of Petroleum Geochemistry China National Star Petroleum Corporation Hefei China The State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation of China Chengdu Institute of Technology Chengdu China

Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data.

关键词： chimney effect (CE) hydrocarbon microseepage oil/gas accumulation.

Co-evolutionary design of discrete structures based on the ant colony optimization

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Progress in Natural Science:Materials International 2007年第9期17卷 1082-1094页

作者： Tao Zhenwu and Xiao Renbin(CAD center,Huazhong university of Science and Technology,{2. 430074,China) CAD center Huazhong University of Science and Technology Wuhan 430074 China

In order to optimize the sizing and topology of discrete structures together and resist the combinatorial explosion of the solution space,a co-evolutionary design(CED)method based on ant colony optimization(ACO)for discrete structures is *** tailored ant colony optimization for the sizing of structures(TACO-SS)and the tailored ant colony optimization for the topology of structures(TACO-TS)are implemented *** analysis shows that the computation complexity of each sub-process in CED based on ACO above is polynomial and it guarantees the efficiency of this *** the parameter settings in TACO-SS and TACO-TS are discussed,the convergence history of a sub-process is studied through an instance in ***,according to the design examples of the 10-bar and 15-bar trusses under different cases,the effectiveness of the CED based on ACO is validated and the effects of the loads and the deflection constraints on the co-evolutionary design are discussed.

关键词： evolutionary design ant colony optimization sizing optimization topology optimization