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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,{2., china 2. institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 430077, china College of Mining Taiyuan University of Technology Taiyuan 030024 China institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 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

A mathematical model for solid liquid and mass transfer coupling and numerical simulation for hydraulic fracture in rock salt

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Progress in Natural science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1,2. and ZHAO Yangsheng1(1. Mining technology institute, {2. University of technology, taiyuan 03002., china 2. Rock and Soil Mechanics institute, Chinese Academy of sciences, Wuhan 430071, china) Mining technology institute Taiyuan University of Technology Taiyuan 030024 China Rock and Soil Mechanics institute Chinese Academy of Sciences Wuhan 430071 China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulations are carried out with the model. The simulation results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.0018t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulations well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

V_2._5/C catalyst for liquid phase oxidation of glyoxal to glyoxylic acid

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science china Chemistry 2009年第7期52卷 1057-1062页

作者： NIU YuLan1,2.& LI RuiFeng1 1 Key Laboratory of Coal science and technology, Ministry of Education, {2. of Special Chemicals, taiyuan University of technology, taiyuan 03002., china 2.Department of Chemical Engineering, taiyuan {2. of technology, taiyuan 030008, china Key Laboratory of Coal science and technology Ministry of Education Institute of Special Chemicals Taiyuan University of Technology Taiyuan China Department of Chemical Engineering Taiyuan Institute of Technology Taiyuan China

A study of the catalytic activity of V2.5/C catalyst for the oxygen oxidation of glyoxal has been made, showing that glyoxylic acid can be formed without control of pH value and there is little oxalic acid from the excessive oxidation of glyoxylic acid. The studies of XRD and TEM have shown that V2.5 diffraction peaks gradually strengthen with the increase of the content of V2.5. With the content of 3% V2.5 and the calcination temperature of 573 K, V2.5/C catalyst displayed the best activity and selectivity. The conversion of glyoxal and the selectivity of glyoxylic acid reached 18.76% and 77.70% after 5 h, respectively. Moreover, V2.5/C catalyst showed small deactivation after recycling three times, which indicates that V2.5/C has a higher stability than noble metal catalysts in the reaction medium.

关键词： glyoxal glyoxylic acid V2.5/C catalyst

Effects of lanthanum on calcium-activated K^+ currents and its kinetics in MC3T3 cells

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science china Chemistry 2010年第6期53卷 1281-1286页

作者： ZHANG LiPing1,2.& YANG Pin1 1Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education institute of Molecular science,Shanxi University,{2. 030006,china 2.ollege of environment and Safety,{2. University of science and technology,{2. 03002.,china Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education institute of Molecular science Shanxi University Taiyuan China College of environment and Safety Taiyuan University of Science and Technology Taiyuan China

Using the whole cell patch-clamp technique,we studied the effects of La3+ on calcium-activated K+ currents and its kinetics of activation and inactivation in non-excitable MC3T3 *** results showed that the calcium-activated outward K+ currents were promoted with increasing concentration of Ca2. in the pipette solution and a voltage- and Ca2.-dependent ***3+ in the bath solution inhibited the currents in a concentration-dependent manner and the inhibition EC50 was 8.2. ± 1.45 μmol/*** the concentration of 50 μmol/L,La3+ significantly changed the Vh of the activation curve and shifted the activation curve to more positive potentials,but shifted the inactivation curve to more negative *** had no effect on the slope factor k of the activation and inactivation *** currents inhibition could induce a series of physiological and molecular biological functions,presumably because of its ability to depolarize the plasma membrane and enhance cell excitability,resulting in increasing Ca2. influx and cytoplast Ca2. *** process may be one of the molecular mechanisms by which La3+ affects the cell growth and function of MC3T3 cells.

关键词： MC3T3 cell potassium ion channel La3+ patch-clamp technique

A new ordered phase forming during ageing in Cu-Ti alloys

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Chinese science Bulletin 1997年第19期42卷 1671-1672页

作者： WEI Yinghui and WANG Xiaotian1. Department of Materials science, taiyuan University of {2., taiyuan 03002., china 2. College of Materials science, Xi’an Jiaotong University, Xi’an 710049, china Ion Beam Laboratory Shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai 200050 China

AGE-hardened Cu-Ti has been an important alloy of investigation in the field of continuousphase transformation due to its complicated transformation processes which involve short rangeordering (SRO), spinodal decomposition (SD), long range ordering (LRO), etc. So far, ithas been a controversial topic whether each process exists, and in what sequence they pro-ceed.

关键词： Ti Cu A new ordered phase forming during ageing in Cu-Ti alloys

Influence of obstacle disturbance in a duct on explosion characteristics of coal gas

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science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 269-278页

作者： WANG Cheng1,MA TianBao1 & LU Jie2.1 State Key Laboratory of Explosion science and technology,Beijing {2. of technology,Beijing 100081,china 2.taiyuan Gas Company,taiyuan 03002.,china State Key Laboratory of Explosion science and technology Beijing Institute of Technology Beijing China taiyuan Gas Company Taiyuan China

In combination with experimental research,numerical simulation is performed to investigate the influence law of the obstacles in a duct on the explosion flame of premixed coal gas and air. The numerical method uses upwind WENO scheme and two-step chemical reaction model. The interaction mechanism is addressed between the compression wave from reflection on the right end of the duct and flame propagation. The reflected wave is found to result in the decrease of flame velocity. On this basis,we analyze the mechanism of the obstacles on flame as well as the law of flow field variation thus caused. The results suggest that,due to the obstacles,deflagration wave is repeatedly reflected,combustible gas mixture is fully compressed,temperature and pressure rise,chemical reaction speed increases,and hence flame intensity is strengthened. At the same time,a tripe point forms as a result of wall reflection of the deflagration wave from the obstacles and furthermore local flame speed increases. As the triple point propagates forward,the flame speed gradually decreases due to dissipation of energy. These conclusions provide a valuable theoretical foundation for the prediction of explosion field,prevention of fire and explosion and effective control of the com-bustion speed and flame propagation speed in detonation propulsion.

关键词： coal gas obstacle explosion overpressure flame speed reflected wave triple point WENO scheme

Microstructure and Mechanical Properties of Ultrafine Grained Mg15Al Alloy Processed by Equal-channel Angular Pressing

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Journal of Wuhan University of technology(Materials science) 2010年第2期25卷 238-242页

作者：王红霞梁伟 College of Materials science and Engineering Taiyuan University of Technology Key Laboratory of Interface science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology

An as-cast magnesium alloy with high Al content Mg15Al was subjected to equal-channel angular pressing （ECAP） through a die with an angle of φ= 90？ at 553 K following route Bc. It is found that the network β-Mg17Al12.phases in the as-cast Mg15Al alloy are broken into small blocks and dispersed uniformly with increasing numbers of pressing passes. Moreover, many nano-sized Mg17Al12.particles precipitate in the ultra-fine α-Mg matrix. The grains are obviously refined. However, the grain structure is inhomogeneous in different areas of the alloy. The average size of the primary phase α-Mg is reduced to about 1 μm while grains of around 0.1-0.2.μm are obtained in some two-phase areas. With additional ECAP passes （up to 8）, coarsening of the grains occurs by dynamic recovery. Room temperature tensile tests show that the mechanical properties of Mg15Al alloys are markedly improved after 4 ECAP passes. The ultimate tensile strength and elongation to failure increase from 150 MPa to 2.9.3 MPa and from 0.05% to 7.4%, respectively. Compared with that after 4 passes, the elongation to failure of the alloy increases but the strength of the alloy slightly decreases after 8 ECAP passes. Fracture morphology of the ECAP-processed alloy exhibits dimple-like fracture characteristics while the as-cast alloy shows quasi-cleavage fractures.

关键词： high-aluminum Mg Alloy β-Mg17Al12.phase ultra-fine grained microstructure mechanical properties equal-channel angular pressing

A study on compressive shock wave propagation in metallic foams

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science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 279-287页

作者： WANG ZhiHua1,2.ZHANG YiFen2.REN HuiLan1 & ZHAO LongMao2.1 State Key Laboratory of Explosion science and technology,Beijing {2. of technology,Beijing 100081,china 2.{2. of Applied Mechanics and Biomedical Engineering,taiyuan University of technology,taiyuan 03002.,china State Key Laboratory of Explosion science and technology Beijing Institute of Technology Beijing China institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology Taiyuan China

Metallic foam can dissipate a large amount of energy due to its relatively long stress plateau,which makes it widely applicable in the design of structural crashworthiness. However,in some experimental studies,stress enhancement has been observed when the specimens are subjected to intense impact loads,leading to severe damage to the objects being protected. This paper studies this phenomenon on a 2. mass-spring-bar model. With the model,a constitutive relationship of metal foam and corresponding loading and unloading criteria are presented; a nonlinear kinematics equilibrium equation is derived,where an explicit integra-tion algorithm is used to calculate the characteristic of the compressive shock wave propagation within the metallic foam; the effect of heterogeneous distribution of foam microstructures on the shock wave features is also included. The results reveal that under low impact pulses,considerable energy is dissipated during the progressive collapse of foam cells,which then reduces the crush of objects. When the pulse is sufficiently high,on the other hand,stress enhancement may take place,especially in the heterogeneous foams,where high peak stresses usually occur. The characteristics of compressive shock wave propagation in the foam and the magnitude and location of the peak stress produced are strongly dependent on the mechanical properties of the foam material,amplitude and period of the pulse,as well as the homogeneity of the microstructures. This research provides valuable insight into the reliability of the metallic foams used as a protective structure.

关键词： aluminum foam heterogeneous intensive pulse loading stress enhancement

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science china(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU Ping2. DONG Qiming2.& LI Hejun1 1. College of Materials science and Engineering, Northwestern Polytechnical University, Xi’an 710072. china 2. College of Materials science and Engineering, Henan University of science and technology, Luoyang 471003, china College of Materials science and Engineering Northwestern Polytechnical University Xi’an China College of Materials science and Engineering Henan University of Science and Technology Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.