Advanced Materials Research Vols. 354-355

Abstract: According to the analysis of the semi-continuous mining system with crushing station set on end-slope and the relation with working wall and non working wall, the calculation method of uncovered end-slope area and the coefficient of slope stability was elicited, considering the external load caused by crushing station location. The variation curve and the law of stability coefficient were also obtained. Combining the field practice, the research conclusion indicates that the crushing station setting of semi-continuous mining system would affect not only the truck transportation distance and the economy benefit, but also the slope stability, which can be used as the theory support to the setting of crushing station in semi-continuous mining system.

Abstract: Taking advantage of the method of big diameter and long drilling-holes in coal seam’ roof instead of roadway method to drainage gas from coal seam, aimed at the condition of deep coal seam and high risk of outburst in Dingji Coal Mine. The amount and rate of drainage gas was increased, and decreased the time and engineering amount of drainage gas, and effectively diminished the risk of outburst of coal and gas. And a new approach adapt to Dingji Coal Mine to drainage gas is acquired.

Abstract: Pile-plank structure is a new foundation under rail. It has been applied in China, because of its advantages that it can control the foundation settlement effectively and speed up the progress of construction. Zhengzhou-Xi'an high-speed rail is designed to a 350km/h high speed rail. To control the post-construction settlement, speed up construction schedule, this measure is applied in the deep collapsible loess foundation, the first time in the world. To guide the engineering design and to form a theoretical system, field test researches were conducted in appropriate working points, mainly including stress-strain test of bearing sheet and contact stress test between bearing sheet and foundation.

Abstract: Catalytic combustion of hydrogen/air mixture inside micro-tube was numerically investigated with detailed gas phase and surface catalytic chemical reaction mechanisms. Combustion characteristics for different reaction models, inlet velocity, tube diameter on surface catalytic combustion reaction, and comparison of numerical and experimental studies were discussed. The Computational results indicate that the surface catalytic combustion restrains the gas phase combustion. The effect of the surface catalytic reaction on the gas phase reaction can be divided to three types. The existence of catalytic wall will help to reach complete reaction in the micro-tube. Some theoretical evidences are provided for the application of catalytic combustion to Micro-electromechanical System (MEMS) and the extension of the combustion limits.

Abstract: This paper shows the result of analytical consideration of the optimality of the solar panel installation for the simple photovoltaic generation system. The power generation is efficiency when the angle of solar panel is to change angle finite times. We adopted the approximated function to figured air mass with sine function or power function in solar radiation data, and calculated the solar radiation to decide optimum angle analytically. Then we have obtained the optimal relation which means the optimal relative angle, and the solar power generation will be made efficiently by using only simple structure.

Abstract: In this paper, the Urea-SCR system is first introduced; then change of the urea solution concentration under different temperatures with time lapsing is given. Meanwhile, conditions for the urea crystallization are analyzed and SCR converter adaptability is tested under high sulfur environment on engine test bench. As the efficiency of NOx conversion is not significantly reduced after aging and the activity of the catalyst is very little damaged by dense sulfur content in fuel, SCR catalyst is able to adapt to the application of high-sulfur-contained fuel environment in our country.

Abstract: Population, economy, energy and environment are the four essential factors of sustainable development. The dynamic variation track, geography center and their inherent mechanism can be described by Gravity center theory. Based on the statistics from 1985 to 2009, centers of gravity for energy production, consumption and CO₂ emission in China were studied in this paper. The results showed that centers of gravity for energy production, consumption and CO₂ emission in China are changing from north to south. The center of gravity for energy production has a more apparent westward character while the southward character of energy consumption is notable.

Abstract: P₂O₅/CaCl₂/Fe₃O₄ composite catalysts for the esterification of oleic acid was proposed. Optimum conditions for the esterification of oleic acid to produce methyl ester of oleic acid were investigated which yielded a maximum conversion of oleic acid to the methyl ester. The variables were: 1) temperature and time of reaction; 2) amounts of catalyst and 3) ratio of alcohol to fatty acid.

Abstract: In order to study the flue gas velocity distribution and pressure drop characteristics inside wet desulfurization Tower, experimental study has been carried out. Flow model is built with geometric scale of 1 / 12 , flue gas velocity ratio of 1 / 1 and different gas entrance angle as 12°and 7°. Experiment result shows that Spray liquid droplets made gas more evenly; The evenness of gas velocity distribution is very poor with very low gas load (<35%);The pressure drop in tower increases with increase of sprayer and increases with increase of gas load; The evenness of gas velocity distribution becomes poor and the pressure drop increases when gas inlet angle changes from 12°to 7°.

Abstract: Effect of substrate conditions, including material type, thickness and radius of substrate, on thermal-shocking stresses of plasma spraying Sm₂Zr₂O₇/ NiCrCoAlY TBCs was analyzed through finite element method. Results show that radial stresses decrease with time increasing, and they decrease with the increasing of distance from center to edge along radius. However, axial residual stresses increse abruptly at the edge of specimen. All residual stresses increse with incresing of thermal expansion coefficient of substrate. Radial stresses increase with substrate thickness increasing, however, they are not effectd by substrate thickness if it is great than 20mm.and axial residual stresses and shear stresses are not effected by the substrate thickness. The maximum values of axial stresses and shear stresses were not effected by sustrate radius. and values of radial stresses remian invariable when substrate radius is over 18mm.