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Rb-Sr isochron ages and significance of bimodal volcanic association in Baimianshi uranium ore-field, South china

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Chinese Science Bulletin 1999年第S2期44卷 3-4页

作者： CHEN Peirong~1, WANG Yinxi~2. NI Qisheng~1, KONG Xinggong~2.and ZHANG Bangtong~2.1. State Key Laboratory of Mineral Deposits, Department of Earth Sciences, nanjing University, nanjing 2.0093. china 2. {2. of Modern analysis, nanjing University, nanjing 2.0093. china State Key Laboratory of Mineral Deposits Department of Earth Sciences Nanjing University Nanjing 210093 China center of Modern analysis Nanjing University Nanjing 210093 China

1 Geologic background THE volcanic U-deposits are generally associated with felsic to intermediate volcanic rock and their sedimentary derivatives. However, uranium mineralization has been found to be spatially associated with thebasalt of bimodal volcanic associations in Baimianshi uranium ore field. Baimianshi uranium ore-field islocated in Baimianshi volcanic-sedimentary basin of south Jiangxi Province. The cover rocks of the basinconsist of a suite of bimodal volcanic-sedimentary sequences. Its basement rocks are two-mica granites ofBaimianshi rock body. The basalt of cover rocks is interbedded with arkoses in lower sequence, and rhyolite or rhyolitic tuff in upper sequence. Uranium minerals mainly occur as disseminations in the

关键词： Rb-Sr isochron ages bimodal volcanic rocks uranium ore-field south china.

Intuitionistic fuzzy hierarchical clustering algorithms

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Journal of Systems Engineering and Electronics 2009年第1期20卷 90-97页

作者： Xu Zeshui1,2.1. Coll. of Economics and Management, Southeast Univ., nanjing 2.0096, P. R. china 2. Inst. of Sciences, PLA Univ. of Science and Technology, nanjing 2.0007, P. R. china Coll. of Economics and Management Southeast Univ. Nanjing 210096 P. R. China Inst. of Sciences PLA Univ. of Science and Technology Nanjing 210007 P. R. China

Intuitionistic fuzzy set （IFS） is a set of 2.tuple arguments, each of which is characterized by a membership degree and a nonmembership degree. The generalized form of IFS is interval-valued intuitionistic fuzzy set （IVIFS）, whose components are intervals rather than exact numbers. IFSs and IVIFSs have been found to be very useful to describe vagueness and uncertainty. However, it seems that little attention has been focused on the clustering analysis of IFSs and IVIFSs. An intuitionistic fuzzy hierarchical algorithm is introduced for clustering IFSs, which is based on the traditional hierarchical clustering procedure, the intuitionistic fuzzy aggregation operator, and the basic distance measures between IFSs： the Hamming distance, normalized Hamming, weighted Hamming, the Euclidean distance, the normalized Euclidean distance, and the weighted Euclidean distance. Subsequently, the algorithm is extended for clustering IVIFSs. Finally the algorithm and its extended form are applied to the classifications of building materials and enterprises respectively.

关键词： intuitionistic fuzzy set interval-valued intuitionistic fuzzy set hierarchical clustering intuitionisticfuzzy aggregation operator distance measure.

Theoretical calculation of the impact work in the alloying non-quenched and tempered steel

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Science china(Technological Sciences) 2006年第3期49卷 257-273页

作者： LIU Zhilin1, LIN Cheng1 & GUO Yanchang2.1. Department of materials and Chemical Engineering, Liaoning Institute of Technology, Jinzhou 12.001, china 2. The Technical {2. of Benxi Iron and Steel Group Corporation, Benxi 117000, china Department of materials and Chemical Engineering Liaoning Institute of Technology Jinzhou China The Technical center of Benxi Iron and Steel Group Corporation Benxi China

Coupled with hot-continuous rolling technology and based on the calculation of the finishing rolling impact work in the non-quenched and tempered Si-Mn steel, the calculations of the finishing rolling impact work in the alloying non-quenched and tempered steel with the elements of Cr, Ni, Mo, W, Cu, V, Nb and Ti are studied with the covalent electron number nA of the strongest bond in alloying phases, the smallest electron density difference ?ρ of phase interfaces, and the number of atom states σ (σ′) which keep the interface electron density continuous. The calculated results show that the finishing rolling impact work of the alloying non-quenched and tempered steel intensely depends on strengthening mechanisms. The solution strengthening, interface strengthening, precipita- tion strengthening of pearlite, and dispersion strengthening will result in the decrease of the finishing rolling impact work; the refinement strengthening, the precipitation strength- ening of V, Nb and Ti in α-Fe-C-V(Nb, Ti), and the residual austenite containing Ni on the boundary of α-Fe-C-Ni will increase the impact work; and the increments or decrements can be calculated with nA, ?ρ, σ (σ′) and weights of alloying elements. The calculation formulas of the finishing rolling impact work in this paper are intergraded with the sug- gested ones of the finishing rolling tensile strength, yield strength, and elongation of the non-quenched and tempered steel. The calculated results agree well with the measured ones.

关键词： alloying non-quenched and tempered steel, electron structure, impact work, calculation.

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 University, Wuhan 430079, china. 2. Presidential Secretariat, Wuhan University, Wuhan 430079, china GPS Engineering Research center Wuhan University Wuhan 430079 China Presidential Secretariat Wuhan University Wuhan 430079 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

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese Science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012. china 2.center for {2. analysis, nanjing University, nanjing 2.0093. china 3. Department of Earth Sciences, nanjing University, nanjing 2.0093. china Second Institute of Oceanography State Oceanic Administration Hangzhou China Centu for materials analysis Nanjing University Nanjing China Department of Earth Sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

The mechanism of breakdown in laminar-turbulent transition of a supersonic boundary layer on a flat plate-temporal mode

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Science china(Physics,Mechanics & Astronomy) 2005年第5期48卷 614-625页

作者： HUANG Zhangfeng 1, CAO Wei 1,2.& ZHOU Heng 1,2.1. Department of Mechanics, Tianjin University, Tianjin 300072. china 2. Liu-Hui center of Applied Mathematics, Nankai University and Tianjin University, Tianjin 300072. china Department of Mechanics Tianjin University Tianjin China Liu-Hui center of Applied Mathematics Nankai University and Tianjin University Tianjin China

Temporal mode direction numerical simulation has been done for the transition of a supersonic boundary layer on a flat plate with Mach number 4.5. analysis of the result showed that during the breakdown process in laminar-turbulent transition, the mechanism causing the mean flow profile to evolve swiftly from laminar to turbulent was that the modification of mean flow profile by the disturbances,when they became larger,led to a remarkable change of its stability characteristics. Though the most unstable T-S wave was of second mode for laminar flow, the first mode waves played the key role in the breakdown process in laminar-turbulent transition.

关键词： supersonic boundary layer, transition, breakdown.

Degradation of Pore Structure and Microstructures in Hardened Cement Paste Subjected to Flexural Loading and Wet-dry Cycles in Sea Water

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Journal of Wuhan University of Technology(materials Science) 2009年第6期24卷 940-944页

作者：张武满 School of Transportation Science and Engineering Beihang University Jiangsu Key Laboratory of Construction materials Southeast University

Hardened cement paste was subjected to the flexural loading and wet-dry cycles in sea water. The degradation of microstructures was obtained using scanning electron microscope （SEM）, and the energy dispersive spectrum （EDS） analysis was carried to analyze the local composition. Mercury intrusion porosimetry （Poremaster GT-60） was used to analyze the degradation of pore structures. The experimental results show that the synergistic action of the flexural loading, wet-dry cycles and sea water leads to significant deterioration of hardened cement paste. The degradation of microstructures in the tensile region is more serious than that in the compressive region. The flexural loading and wet-dry cycles accelerate the chemical attack of sea water.

关键词： hardened cement paste pore structure microstructures flexural loading wet-dry cycles sea water

Diamond synthesis from a system of chromium-carbide andNi_(70)Mn_(2.)Co_5 alloy

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Chinese Science Bulletin 1998年第24期43卷 2063-2066页

作者： LI Liangbin 1, JIANG Jinchun 1, HONG Shiming 1, ZHONG Yumao 2.and ZHANG Xinyuan 2.1. Institute of Applied Physics, Sichuan Union University, Chengdu 610065, china 2. center for {2. and Test, Sichuan Union University, Chengdu 610065, china Institute of Applied Physics Sichuan Union University Chengdu China center for analysis and Test Sichuan Union University Chengdu China

In order to ascertain the mechanism of interaction between carbide and metallic catalyst and formation of diamond under high pressure and high temperature, and find a new method to synthesize diamond with special properties, it is necessary to investigate the reaction behavior of different carbides and metallic solvent_catalysts under high pressure and high temperature. A system of Cr-3C-2.powder and Ni 70Mn 2.Co 5 alloy in weight ratio of 1∶6 was treated under 6 0 GPa and 1 500℃ for 2., 30 or 60 min respectively. X_ray diffraction of the samples indicated the Cr 3C 2.decomposed partially after high pressure and temperature treatment, and Cr 7C 3, Cr and diamond formed respectively. There was not any trace of graphite in the samples. The result suggested that the separated carbon atoms could form diamond directly without conversion process of graphite into diamond. The observation of SEI, WDX and EDX also showed that diamond crystals were synthesized in the system, which have perfect surfaces and shapes, with the average grain size of about 40 μm. The properties of the crystals are being investigated.

关键词： chromium_carbide high pressure synthesis diamond.

Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan University of Technology(materials Science) 2010年第1期25卷 162-166页

作者：郭伟 Department of Material Engineering Yancheng Institute of Technology Institute of Material Science and Engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2.content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2.and AFt. The cement with 30% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product