Abstract: Baguamiao gold deposit locates in the Devonian low-grade metamorphic rocks. According to a study on fluid inclusions in quartz from the main mineralizing stages, it was found that the ore-forming fluid was of salinity, from low, middle to high salinity (with daughter minerals). Pyrite and salt were identified among these daughter minerals by SEM/EDS and EPMA, LRM was also used for checking the composition of fluid inclusions. All of fluid inclusions was detected to be rich in CO2 and CO, SO2, CH4, H2S, and C2H2. C2H4 was also detected in some of them. It is concluded that the ore-forming fluid is of more reducing and complicated physical-chemical conditions.
Abstract: An approach to the development of a geological database and its mangement system was presented, including the methology for design, implementation, and input data manipulation of the geological system. Besed on ADO (Active Data Object) and its relative technologies, the geological database and its management system were developed, and a case study with data from Chengchao Iron Mine was conducted. The results have demonstrated the validity of the system.
Abstract: The heat output of coal, the rate of oxygen consumption and the influence function of coal size were tested by a big coal spontaneous combustion experiment unit. The relationship between the coefficient of heat convection and air flux of roadway was studied. Based on the conservation principle of energy and the real conditions, such as coal temperature, air temperature, geometry size of roadway, air flux, oxygen concentration in the loose coal around the roadway etc, the terminal parameters resulting in coal spontaneous combustion are proposed, the conditions and the method for determining coal spontaneous combustion are set up, and the quantitative index determining the danger zone of coal self-ignition is obtained.
Abstract: The characteristics of coal spontaneous combustion were investigated through programmed temperature experiment and the concentration of CO, CO2 etc for coal with various sizes was measured at different temperatures. The selection of index gases was discussed. The law of concentration change for CO, CO2 etc and the relation of consuming oxygen velocity to coal temperature and size were analyzed. The smaller the coal size and the higher the temperature, the more intense the reaction of coal and oxygen. The results can direct the prevention and treatment of fire in mine.
Abstract: A general method of alarming for mine management information systems was designed. The alarming system is independent of the work system, and provides alarming functions to the work system by visiting in turn the alarm information data table which is produced by alarm events in the work system and by producing the alarm display in the work system. Also it can process alarm information as a whole and refrain from the alarming conflict.
Abstract: Under the random vehicle loading condition, according to the dynamic characteristics of soil, the active patterns of soil and the violation for retaining walls were analyzed in a rudimental procedure. Based on the Rankine active earth pressure theory and the limit equilibrium condition of retaining walls, three parameters were introduced into the program of instability analysis. Carrying the critical anti-sliding force and anti-sliding moment as analytical formulas, and taking into account the limit equilibrium condition of the wall-soil system, two equations were well established. A practical engineering was analyzed by this method and numeriacl analysis. The result shows that the angle of sliding wedge of subgrade soil are almost in the same value with different analytical measurements.
Abstract: A technological process for the disposal of mixed electroplating wastewater under the alkaline condition was chosen by thermodynamic analysis, theoretical calculations, and experiment investigations. In this process, NaClO was chosen as oxidant, Na2S and FeSO4 as reducers. The optimal ratio of Na2S and FeSO4 was determined as Na2S 80%-90%, FeSO4 10%-20%. Using Na2S and FeSO4 as oxidants can reduce the sludge quantity by 60%-70% comparing with using FeSO4 only. A real project by this technology has already obained good results.
Abstract: Non-metallic inclusions of 72A Steel investigated invest using multi-measurements in Jiuquan Group. The amount, type, source, composition and distribution of the inclusions were discussed. The results show that more than 60% of inclusions in billet come from exotic inclusions, and 40% of inclusions in billet origin from oxides. The main reason of wire-breaking is large exotic inclusions. It is important to control the composition, shape, size and distribution of these endogenous and exotic inclusions.
Abstract: The D2EHPA-TOA organic phase was used as the solvent-extraction system for the concentration of zinc and the separation of ferric ion from the biochemical lixivium of low-grade zinc sulfide. The results indicate that the system can improve evidently the performances for zinc extraction and iron removal from zinc sulfide. The zinc saturated capacity increases by 12%. The complete stripping of zinc from the zinc-loaded D2EHPA-TOA organic phase can be achieved by 0.25 mol/L H2SO4 through one stage, while -68% of ferric iron is stripped from the Fe-loaded D2EHPA-TOA organic phase only by 4 mol/L H2SO4 through one stage.
Abstract: Ta films were deposited on Si substrates precoated with SiO2 by magnetron sputtering. The SiO2/Ta interface and the Ta5Si3 standard sample were investigated by X-ray photoelectron spectroscopy (XPS) and peak decomposition technique. The results show that there is a thermodynamically favorable reaction at the SiO2/Ta interface. The more stable products Ta5Si3 and Ta2O5 may be beneficial to stop the diffusion of Cu into SiO2.
Abstract: Element mutual diffusions during hot iso-static pressing (HIP) diffusion bonding were simulated using DICRTRA-THERMO-CALC software. The calculating results show that the simulation regulations are agreeable with experimental results. Based on this simulation model, the effect of hold time and temperature on Al mutual diffusion during HIP were calculated, showing that this dynamic computer simulation can offer the processing prediction and the optimum HIP diffusion bonding processing.
Abstract: The stress corrosion susceptibility of the titanium alloy TA7 in various alcohol solutions and the Cl- ion effect were investigated by using the SSRT testing method, SEM analysis and metallographic examination. The results show that the titanium alloy exhibits obvious susceptibility to SCC in ethyl alcohol and methyl alcohol and but more striking susceptibility to SCC in 0.6% HCl-methyl alcohol. SCC cracks of the titanium alloy in these solutions initiated in general from the bottom of pits.
Abstract: The hot continuous rolling process for φ200 mm round bars of a hot work steel is simulated by using the three-dimensional thermal-mechanical coupled elastoplastic finite element method. The changes in rolling force and torque during the rolling process are calculated precisely. As a result, the roll strength and profiles can be verified and/or modified, from which a more reliable roll pass schedule can been chosen.
Abstract: In order to manufacture anisotropic magnet powders from sintered NdFeB magnet, the fracture behavior of sintered NdFeB magnet in the mechanical crush process at high temperatures was studied. The experimental results show that the sintered NdFeB magnet can be crushed to fine powders much more easily than that at room temperature as the crushing temperature is raised to above 600℃, which results from eutectic formation of the minor liquid phase at the grain boundary area. The morphology of the crushed powders exhibits that the fracture at temperatures higher than the eutectic temperature tends to be intergranular instead of transgranular which occurs at lower temperatures. Through X-ray diffraction analysis the magnetic powders obtained by a crush process at higher temperatures shows much higher diffraction peaks of the Nd-rich phase.
Abstract: The microstructure of the fusion zone and the changing rule of the carbon-enriched zones in aging 0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints were studied by optical microscope and scanning electron microscope (SEM). It is found that the carbon-enriched zone, to a certain extent, initially forms in austenitic steel adjacent to the weld interface in the fusion zone. With increasing the aging time, the carbon-enriched zone gradually increases. After it reaches the maximum it begins to decrease and goes to disappear finally. The changing rule of carbon-enriched zone width is different from the past A302/1Cr5Mo dissimilar welded joints.
Abstract: A tempreture field model was proposed based on the law of energy conservation. The heat exchanging coefficients of water-flow cooling and jetflow shocking on the plate surface were gained using the bound conditions. The correct lateral cooling curve with flexible suitability was obtained. The tempreture distribution on the plate is uniform by the method that the pipes with the same diameter are arranged in different row distances.
Abstract: A 3-dimensional strip rolling analysis model considering strip lateral flow is developed in order order to overcome the disadvantages in the traditional theories. The distribution of specific rolling pressure, transverse stress, exit strip profile, edge drop and width spread are obtained by numerical calculations. Calculated examples under different kinds of rolling conditions conform to the reality, and results show that the developed 3-dimensional program is applicable for the narrow strip or wide strip, single stand or tandem mill.
Abstract: Using measured data, an algorithm of pass adaptation is developed for plate rolling. This algorithm can adjust the model better because the adjusting scale depends on the ratio of measured rolling force to calculated rolling force. Results show that this adaptive algorithm is effective in practice.
Abstract: An intelligent electric power steering system was designed. The system can detect the torque by human steering real-timely, and control the torque by an induction motor according to that by human and the peed in a prescribed ratio. Experimental results show that the torque by a motor responds to the change of the torque by human quickly and precisely.
Abstract: Focusing on the nonholonomy and uncertainty of wheeled mobile manipulators, a robust following controller was presented, the dynamic following controller was designed by using the method of backstepping kinematics into dynamics, and the neural network controllers for the mobile platform and manipulator by the genetic algorithm to search for the neural network's weights. The uncertainty terms were compensated. The robust controller was simulated by using the simulink of Matlab and C MEX-file. The results show that the controller has better robustness.
Abstract: A fuzzy compliant control method is presented for robot assembly. No model parameters of assembly are required in the experiment and thereby, large quantity calculations can be saved. Yet the force information of variables is not needed to introduce into the procedure of assembly. Experiment results obtained show considerable feasibility.
Abstract: A solid granule flowrate model was proposed by using simple dynamic recurrent neural networks. Considering dynamic recurrent neural network's shortcomings of complex structure and low convergence speed of training algorithm, a kind of recurrent neural network was adpted. whose structure is very simple. This RPE algorithm was adapted to the simple recurrent network by making improvement and complementarity, and the weight and the threshold of the network can be adjusted at the same time. The results of modeling show the speediness and the high-precision of this method.
Abstract: Two algrithms for data cube-based intra-dimensional association rules mining are proposed by lucubrating into the structure of data cube and integrating with the technology of online analytical processing. Experiment results show that the two algorithms are respectively suitable for different support-constrained association rules mining.
Abstract: For determining the feasibility of offering real-time services in transport communications, the resource and admission control algorithms was proposed for real-time transport connections. A necessary and sufficient condition for the schedulability of n real-time transport connections was given for deterministic guarantees and statistical guarantees of QoS (Quality of Service). The buffer space needed for each real-time transport connection was also calculated. These results are beneficial for the high-speed transport protocol design and implementations.
Abstract: According to the demand in practice, the method of determining the order in an AR(p) model is extended, and the method of determining the order based on local residual sum of squares is introduced. This method shows that the theory of multiple objective programming and the local character of some sequences can be combined. An example shows that with the method of determining the order based on local residual sum of squares in AR(p), the precision of forecast values increases. The supremum of the order of the AR(p) model is given and proved.
Abstract: The KDD* model, a bench in the field of structured data mining, is proposed based on the double-bases (database and knowledge base) cooperation mechanism. In order to improve the intelligence of KDD*, an intelligent data mining system based on the multi-agent technologies is designed to realize data preprocessing, data mining, automatic extracting of knowledge, synchronous evolving and cooperating of basic database and knowledge base, knowledge evaluating and explaining.
Monthly, started in 1955 Supervising institution：Ministry of Education Sponsoring Institution：University of Science and Technology Beijing Editorial office：Editorial Department of Chinese Journal of Engineering Publisher：Science Press Chairperson：Ren-shu Yang Editor-in-Chief：Ai-xiang Wu ISSN 2095-9389CN 2095-9389
