Abstract: Based on the research of the control mechanism of geology structure for the outburst and the distribution rule, the theory and method of tectonophisics were applied to the forecast of outburst. It was proposed that the outburst-prone tectonophisical environment is composed of 4 factors, that is tectonic combination characteristic, tectonic stress field, and tectonic coal and gas. The control mechanism of all factors of the outburst-prone tectonophisical environment was discussed. It was shown that the synthetic action of multi factors of the outburst-prone tectonophisical environment controls the outburst in the geology tectonic area, and this provides the theoretic basement for forecasting the outburst proneness due to the geology structure. Engineering practice proves that the outburst of coal and gas can be forecasted accurately with the analysis of the outburst-prone tectonophisical environment.
Abstract: Based on the displacement, stress and energy coupled monitoring technique, the trends of subsidence rate, characteristic parameters of acoustic emission, and seepage in the subsidence area were statistically analyzed, respectively. The seepage influence on structural dynamic damage was evaluated synthetically. The result showed that the deformation rate was accelerating seriously and the evaluative trend between seepage and damage can be simply estimated by acoustic emission monitoring.
Abstract: A methodology is presented for the spatialization and regularization of geological data in developing a volume visualization system of mineral deposits. In the process of spatialization, drill holes are treated as a series of broken lines with the spatial direction, and the grade at a point is obtained through layering of the deposit with one meter depth. The regularization of geological data is realized using the Shepard method with the regionalization of mineralization taken into account through geostatistical variograms. A case of underground iron ore mine is studied to verify and validate the methodology.
Abstract: A management information system is developed based on components and architecture. According to the relationship between the management role and the work, the role components and work components with independent functions are built which will be used as basic components to re-organize the management work flower, and the message activating mechanism of components is built to control the component activity order. The methods above-described can improve the re-organizing property of the management information system.
Abstract: A steady state, two-dimensional numerical model is undertaken to describe coupled liquid steel's turbulent flow and heat transfer with solidification for the Fe-C binary alloy in a crystallizor of inverse casting. The solid-liquid phase change phenomena are modeled by using the continuum formulations and considering the mush zone as porous media. The turbulence flow in the crystallizor is accounted for, using a modified version of the low-Reynolds-number κ-ε turbulence model. The flow pattern in liquid zones and the temperature distribution in solid, mushy and liquid regions are predicted. The numerical analysis indicates that the residence time of the mother sheet in the crystallizor is one of the key parameters. The effects of some other main parameters on the solidification behavior are also studied, such as the thickness and the initial temperature of the mother sheet, the superheat degree of liquid steel, etc.
Abstract: Some necessary data gathered from 5 steel samples treated by different alloys was analyzed through a series experiments of Mg-Ca-based desulphurizers. The results show that Mg-Ca-based alloys have the capacity of deep desulphurization. Mg-Ca-based desulphurizers can overcome the defects of boiling away easily of pure Mg or pure Ca, and enhance every elements' capacities in deoxidation or desulphurization.
Abstract: In order to recycle Zn-bearing dusts in Baosteel, hot metal desiliconization with the dust was investigated in laboratory. The factors which affect desiliconization and Zn evaporation were discussed. Theresults show that the mixture of EAF dust and BOF dust containing Zn for hot metal desiliconization at 1500℃is better than sinter dust. The Zn evaporation rate in the slag can reach to 99 % and the height of foaming slag in desiliconization is lower. It benefits desiliconization by increasing temperature, enhancing stirring intensity or increasing the initial content of [Si].
Abstract: A study was carried out to find out the suitable conditions for zinc extraction from acidic zinc sulfate solution by two different extractant systems of di-(2-ethylhexy)-dithiophosphoric acid (D2EHPA) and D2EHPA-Trioctylamine(TOA) respectively in the background of comprehensive utilization of sulfureted sodium. The result shows that the D2EHPA-TOA synergistic extractant system is prior to the D2EHPA one without TOA when the degrees of extraction and strip and the economic benefits are taken into account. A technique to reclaim zinc from bacterial leach solution is suggested.
Abstract: The characteristics of γ→ε transformation and stacking faults in the sub-stability Fe-12Cr-10Mn(W,V) alloy (84) after solution-treated followed by cooling in air and by quenching into ice water and these in the phase stability Fe-13Cr-17Mn(W,V) alloy (85N) after solution-treated followed by water, solution-treated followed by deformation were investigated by transmission electron microscope (TEM) and X-ray diffraction. Some ways to increase the phase stability were also carried out through analyzing the influence of some elements on the transformation of γ→ε.
Abstract: The cathode LSM powders of solid state fuel cells (SOFC) were manufactured from solid state reaction materials such as La2O3, MnO2, and SrCO3. The modern instrument, such as XRD, TGA/DTA etc, were used to research the processing steps of LSM fine powders. During the processing, there was La2SrOxexisted, no LaMnO3. The reaction steps were described as follows. First, La2O3+SrCO3→La2SrOx+CO2, andthen La2SrOx+MnO2→La1-xSrxMnO3, finally got La1-xSrxMnO3. This result is different from the recognizedsteps during the LSM processing, in which La2O3+MnO2→LaMnO3 first, and then LaMnO3+SrCO3-La1-xSrxMnO3.
Abstract: The multi-element Ni-Cr-Mo-Cu surface alloying layer on the matrix of low carbon steel 20 was investigated by means of the double glow plasma surface alloying technique. The results show that the technical parameters have obvious effect on the total content of alloyed elements and the thickness of the alloying layer. The optimum parameters of alloying Hastelloy C-2000 were obtained by the orthogonal test.
Abstract: The densification behavior, phase composition, mechanical properties and microstructure of hot-pressed multi-phase β-Si3N4/α-Sialon ceramics were studied by XRD, mechanical measurements andSEM. The results indicated that the multi-phase β-Si3N4/α-Sialon ceramics mix the mechanical properties ofβ-Si3N4 and α-Sialon, the phase composition and mechanical properties can be tailored by adjusting the composition of start powders. Compared with a-Sialon ceramics, the strength and toughness of the multi-phase β-Si3N4/α-Sialon ceramics are increased by in-situ toughness because of adding the β-Si3N4 phase with a highaspect ratio.
Abstract: The distribution of thermal stresses for an empty cylinder of Functionally Graded Materials (FGM) with axial symmetry is obtained, and the Genetic Algorithm (GA) is applied to the optimization problem of material composition for an empty cylinder of FGM with axial symmetry. Based on the thermal elasticity theory and computational method, the numerical calculations are made using a genetic algorithm. The minimum thermal stresses and optimum combination are obtained for an empty cylinder of FGM.
Abstract: Using XRA, SEM/EDS and FEM methods, the degradation and distortion of wall painting from early Western Han dynasty were studied. According to our study, the degradation and distortion of wall painting relate to the temperature and humidity of environment. The biggish difference of mechanics capability of materials used in conservation and restoration is the main reason of the distortion and cracking of wall painting. This result can provide the design base for the conservation and restoration of the wall paintings. The scientific research of materials and mechanics of materials to conservation of culture relics is the important method.
Abstract: The sensor characteristics of CFRP unidirectional laminates were studied by measuring the resistance changes while tension or cyclic tension was applied. The results show that the characteristics of resistance change are different at different ply angles. These characteristics can reflect more information than stress and strain. It is found that CFRP unidirectional laminates have piezoresistive effect. With an increase in stress,the piezoresistive effect increases. The piezoresistive effect of off-axis and 90° CFRP laminates is strongerthan that of 0° CFRP laminate and with the increase of the ply angle the piezoresistive effect increases. By useof the characteristics of resistance change, the CFRP unidirectional laminate can be inspected in-situ and the damage can be diagnosed by itself.
Abstract: The study focuses on fulfilling the on-line thermomechanical treatment(OLTM) process by intermediate cooling, reheating and reduction rolling of rough tubes after mandrel rolling. The process is beneficial to high qualities and lower costing for seamless tubes. It is found that the austentic grain grade by OLTM is smaller 2.5-3 ASTM than that by direct sizing, the properties of 40Mn2V steel by OLTM are the longitudinal toughness Ak≥23J,σ0.5≥555Mpa, σb≥820Mpa, elongation δ5≥23%, matching the property demands ofAPI Standard about N80 grade oil casing. The vital factors of improving impact toughness are the degree of austenite decomposition during intermediate cooling and the proper reheating temperature.
Abstract: Both the Stribeck curve and friction coefficient were mensurated before and after the Lα-DPPC was added into the HA lubricate system by pendulum friction apparatus. It was found that the system friction coefficient decreased sharply after Lα-DPPC was added. From the Stribeck curve, the lubricate mechanism of the lubricate system could change from the mix lubricate to the liquid film and mix lubricate. It is speculated that the interface characteristic must be changed because of Lα-DPPC. In order to prove this speculation, surface tension was tested when Lα-DPPC was added into the HA lubricate system, and an analysis of IR spectra was done on Lα-DPPC. The results show that Lα-DPPC has hydrophilic and hydropholic characteristics, and acts as a surface active agent in lubricant, which decreases surface tension greatly. This contributes to film formation in the system and increases lubricate effect.
Abstract: The electrochemical storage of energy was considered in a special kind of active carbon materials used as capacitor electrodes. The porous carbon material prepared by KOH and vapor re-etching exhibits perfect physical structure and properties. Its good electrochemical performances were confirmed by the experiment of charge/discharge and the specific capacitance of active carbon was 173.2 F/g. Under the large discharge current condition, the specific capacitance of EDLC decayed only 12 F/g. A evaluation of capacitor performance by voltammetry characteristics was also discussed. A hybrid power source consisting of Nickel-hydrogen and double layer capacitor was demonstrated to power successfully a simulated power load encountered in communication equipment. The new technique of getting high working voltage for capacitor was discussed in detail. The working voltage over 10 V and the resistance less than 250 Ωm was obtained.
Abstract: There are some problems if adopting conventional theories such as the double electric layer and the Donnan equilibrium to explain the permselectivity of ion exchange membranes. A hypothesis named the forming of cavities and double electric layer is proposed. According to the hypothesis, ions migration within membranes form the ion-cavities inside membranes and the double electric layer beside membranes. It is the double electric layer that let counter-ions enter membranes from diluted water, and the ion-cavities that let counter-ions pass through the membranes and enter concentrated water. The hypothesis of the forming of cavities and double electric layers can explain the permselectivity of membranes on different occasions such as the electric field or non-electric field.
Abstract: Because of the variation of strip steel gage along its length during the Flying Gage Change (FGC) process of a tandem cold-rolling mill, it is unsuitable to apply the routine formula into its tension calculation. As to the question, a new tension calculation model of wedged strip steel was proposed and generalized into the strip steel with any shape. A discrete model was deduced using the numerical computation method in order to apply the model into control and simulation during the FGC process.
Abstract: An architecture of the design for assembly (DFA) is proposed. Through the discussion on the key technologies of the DFA such as the product assembling model, assembling sequence planning, mechanism movement analysis and synthesis, assembling process simulation, and evaluation of DFA, the goal of DFA is realized.
Abstract: According to the current situation and development tendency of automatic doors, and with the demand of practical production, a software about computer-aided design for the automatic door porch plan is provided based on the principle of engineering mechanics. This method can optimize design procedures and upgrade the efficiency and quality of the engineering drawing.
Abstract: The mathematical model and control system structures of self-cascade induction machine drives is proposed, which is firstly developed in the world successfully. According to experimental results, the system dynamic & static performance is analyzed which is the same as DC drives.
Abstract: An optimization method based on genetic algorithms is introduced for HCR (hot charge rolling) manufacture plan. Different from the optimization method based on MTSP, it need not determinate the number of rolling cycles. The makeup characteristic of rolling cycles is applied in this method, and the number of rolling cycles is optimized during the makeup optimization. Simulation results show that this method can find out the feasible HCR manufacture plans quickly.
Abstract: Multi-objective evolutionary algorithms which use non-dominated sorting and sharing have been mainly criticized for the problems, (1) O(mN3) computational complexity (where m is the number of objectives and n is the population size), (2) non-elitism approach, and (3) the need for specifying a sharing parameter. This paper suggests a non-dominated sorting based the multi-objective evolutionary algorithm INSGA which alleviates all the above three difficulties. Simulation results on five difficult test problems show that the proposed INSGA is able to find much better spread of solutions in all problems compared to NSGA.
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
