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A Fuzzy Model for Evaluating the mining Condition of Underground Coal Mines

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 242-245页

作者： Zhongrue Li Shaowen Zhang(Resources engineering school, {2. of science and technology beijing, Beding 100083. china) Resources engineering school University of Science and Technology Beijing Beijing 100083 China

In mining industries no mines are identical and each mine has its own unique set of mining conditions. In order to study thecondition of mines for efficiency, safety and economy reasons, a fuzzy model is presented based on fuzzy evaluation. Relevant data fromfive mines were collected and the model was used to evaluate the mining condition of these mines. The evaluation results are in conformity with the real situation.

关键词： fuzzy model mining condition coal mine

The evolution and morphological stability of a spherical crystal

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science china(Technological sciences) 2008年第3期51卷 225-243页

作者： CHEN MingWen1,2. WANG ZiDong2.& XU JianJun3,4 1 school of Applied sciences, {2. of science and technology beijing, beijing 100083. china 2.school of Materials science and engineering, {2. of science and technology beijing, beijing 100083. china 3 school of Mathematical sciences, Nankai {2., Tianjin 300071, china 4 Department of Mathematics and Statistics, McGill {2., Montreal H3A 2.6, Canada 1. school of Applied sciences University of Science and Technology Beijing Beijing 100083 China 2. school of Materials science and {2. University of Science and Technology Beijing Beijing 100083 China 3. school of Mathematical sciences Nankai University Tianjin 300071 China 4. Department of Mathematics and Statistics McGill University Montreal H3A 2K6 Canada

The growth model of a spherical crystal in the undercooled melt including the surface energy, interfacial kinetics and convective flow is established. The effect of the convective flow induced by a small far field flow on the evolution and morphological stability of the interface of the spherical crystal is studied. The interface shape of the spherical crystal, which is affected by the far field flow, and the dispersion relation of the growth rate of amplitude of the perturbed interface are derived. It is shown that the convection induced by the far field flow makes the interface of the growing spherical crystal further grow in the upstream direction of the far field flow and inhibit growth in the downstream direction; the interface of the decaying spherical crystal further decays in the upstream direction and inhibits decay in the downstream direction. The theoretical result suggests that both the growth of the sphere in the upstream direction and the decay of the sphere in the downstream direction make the spherical crystal tend to evolve into an oval; the morphological stability of the interface depends on a certain radius R c such that the spherical crystal is unstable when its radius is greater than R c and stable when its radius is less than R c . The surface energy and interfacial kinetics have strong stabilizing effects on the growth of the spherical crystal. In the meantime interfacial kinetics is a table factor of the interface when the interface of the sphere is growing; it is an unstable factor of the interface when the interface is decaying.

关键词： solid-liquid interface spherical crystal convective flow crystal growth morphological stability

SEM in-situ Fatigue Observation on Crack Initiation and Growth from Inclusion in P/M Rene95 Superalloy

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Journal of university of science and {2. beijing 2001年第3期8卷 195-197页

作者： Lina Zhang, Jianxin Dong, Xishan Xie Material science and engineering {2., university of science and technology beijing, beijing 100083. china Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

A special designed experiment was conducted for observing crack initiation and growth in P/M Rene95 superalloy under tension-tension loading by self-made SEM in-situ fatigue loading stag. Several alumina inclusion particles exposed at the specimen surface were observed carefully. During fatigue test inclusions led to cracks initiation. The cracks can be formed by two mechanisms. Generally, the cracks nucleated at the interface between inclusion and matrix. Sometimes, cracks were also formed inside the inclusion. As the increase of cycles, some cracks at the interface between inclusion and matrix broadened and propagated along the direction about 45 degrees to the loading axis. On the other hand, the cracks inside the inclusion propagated in the inclusion and towards matrix.

关键词： inclusion P/M superalloy LCF SEM in-situ fatigue

Electrochemical Studies of Lithium Intercalation into Graphite Film Electrode for Li^+-ion Batteries

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 48-50页

作者： Chuangang Lin Weihua Qiu Qingguo Liu Material science and engineering {2., university of science and technology beijing, beijing 100083. china Material science and engineering {2. University of Science and Technology Beijing Beijing 100083 China

To study the electrochemical kinetic properties of the Li/Graphite system, cycle voltammerty (CV), ac-impedance and chro- noamperometry (CA) techniques have been used. The results showed that the diffusion of lithium ions in Li_xC_6 is the rate-determining step. The chemical diffusion coefficients of lithium (D_Li) have been estimated for different x values. As for the same material, the value of D_Li was calculated in order to compare the differences among the three techniques.

关键词： electrochemical studies graphite Li^+-ion batteries

The precipitation and effect of nano nitrides in HSLC steel

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science china(Technological sciences) 2008年第7期51卷 989-998页

作者： FU Jie1, LIU YangChun1,2.& WU HuaJie1,3 1 school of Metallurgical and Ecological engineering, {2. of science and technology beijing, beijing 100083. china 2.Shougang technology Research Institute, Shougang (Group) Corporation, beijing 100041, china 3 Metallurgical engineering Research Institute, {2. of science and technology beijing, beijing 100083. china 1. school of Metallurgical and Ecological engineering University of Science and Technology Beijing Beijing 100083 China 2. Shougang technology Research Institute Shougang (Group) Corporation Beijing 100041 China 3. Metallurgical engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

The existing forms of N and Al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of AlN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into AlN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. Aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043%. The precipitation of AlN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is AlN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure AlN, but have complex compositions.

关键词： thin slab casting and rolling high strength low carbon steel AlN nano nitride precipitation strengthening

Real estate appraisal system based on GIS and BP neural network

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中国有色金属学会会刊：英文版 2011年第S3期21卷 626-630页

作者： LIU Xiao-sheng1, DENG Zhe1, WANG Ting-li2.1. school of Architecture and Survey engineering, Jiangxi {2. of science and technology, Ganzhou 341000, china 2. school of Applied science, Jiangxi {2. of science and technology, Ganzhou 341000, china [a] school of Architecture and Survey engineering Jiangxi University of Science and Technology Ganzhou 341000 China [b] school of Applied science Jiangxi University of Science and Technology Ganzhou 341000 China

For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was designed which includes appraisal model, trade case, GIS database and query analysis module. With the help of the L-M algorithm in MATLAB software, BP neural network was improved and the trade cases were trained, then the BP neural network which has already been trained was tested. At the same time, the BP neural and GIS were put together to construct the hedonic price estimate model. The C# and ArcGIS9.3 were used to achieve the system in VS2.08. City basic geographic data and real estate related information were used as the basic data in practice. The results show that the functions of querying, adding and editing the spatial data and attribute data are achieved and also the efficiency and accuracy of real estate are improved, so that the new method of real estate is provided by the system.

关键词： BP neural network GIS hedonic price real estate appraisal

Fabrication of pure copper rods containing continuous columnar crystals by continuous unidirectional solidification technology

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Journal of university of science and {2. beijing 2004年第3期11卷 240-244页

作者： Hong zhang Jianxin Xie Zidong Wang Materials science and engineering {2., university of science and technology beijing, beijing 100083. china Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Pure copper rods containing continuous columnar crystals were fabricatedusing the downward CUS (Continuous Unidirectional Solidification) equipment. When the technologicalparameters were set as the ranges of mould temperature 1100-1300℃, cooling distance (the distancefrom the exit of the cast mould to the start point of cooling) 10-2. mm, casting speed 0.2.2.5 mm/s,cooling water (2.-2.℃) volume 1000-132. L/h, and when these parameters matched reasonably, the CUSprocess was performed stably, and pure copper rods containing continuous columnar crystals withbright and smooth surface were produced. The dendritic arm spacing of the crystals in copper rodsdecreased with increasing the casting speed. The results of the texture by X-ray diffractionanalysis showed that the rods has strong fiber texture.

关键词： copper continuous unidirectional solidification mould temperature castingspeed microstructure texture

Electrochemical studies of nickel deposition from aqueous solution in super-gravity field

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science china(Technological sciences) 2007年第1期50卷 39-50页

作者： GUO ZhanCheng1,2. GONG YingPeng2.& LU WeiChang2.1 Metallurgical & Ecological school, university of {2. and technology, beijing 100083. china 2.Institute of Process engineering, Chinese Academy of {2.s, beijing 100080, china 1. Metallurgical & Ecological school University of Science and Technology Beijing 100083 China 2. Institute of Process engineering Chinese Academy of Sciences Beijing 100080 China

The effect of super-gravity on electrochemical deposition of nickel from aqueous solution was studied. The SEM pictures show that the microstructure of nickel film deposited under the super-gravity condition is finer and more uniform compared with that obtained in normal gravity condition, and the crystal grains diminish with the increase of super-gravity coefficient. The XRD patterns indicate that the arrangement of crystalline grains of nickel film deposited under the super-gravity field is more regular, and the crystalline grain sizes decrease with the increase of super-gravity coefficient. Toughness, tensile stress and hardness of the nickel film are markedly raised with the increase of super-gravity coefficient, and hydrogen content in the nickel film decreases with the increase of super-gravity coefficient. From the polarization curves of hydrogen evolution reaction under the super-gravity condition, a significant reduction of over-potential on electrode was found when current density increased. The process of hydrogen evolution reaction was enhanced under the super-gravity condition. The electro-deposition rate, the microstructure and properties of deposited nickel film under super-gravity condition were still affected by the relative orientation between inertia force and depositing surface. It is favorable to gain the nickel film with better mechanic properties when inertia force orientates vertically towards depositing surface. Keywords super-gravity - electrochemistry - electro-deposition - nickel film Supported by the Notional Natural science Foundation of china (Grant No. 50674011)

关键词： super-gravity electrochemistry electro-deposition nickel film

Future Trends of Deep Sea Bed mining technology

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 4-7页

作者： Yan Feng Haoran Li Wenming Zhang (Resources engineering school, {2. of science and technology beijing, beijing 100083. china) Resources engineering school University of Science and Technology Beijing Beijing 100083 China

The present status of deep sea bed mining technology for polymetallic nodules has been critically examined in light of its history of development the UNCLoS (the United Nation Convention on the Law of the Sea) regime and the current trends in *** critical technologies have been highlighted and the need for system integration underscored. The deep sea bed environment and the {2. challenge were presented and the necessary features of the deep sea bed mining system for commercial mining was analyzed. The key accomplishments, problems and future bends in research in the development of the mining system are also discussed. Finally, it points out that the technology gaps can be filled by the bine commercial mining is undertaken as a result of market conditions in its favor.

关键词： deep sea bed mining, UNCLoS TIS (Total Integrated System), polymetallic nodules mining system