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analysed and calculated by this model. The result shows that rock particle segregation can be controlled by adjusting the relevant parameters like the maximum size of rock and chute angle. The result can be applied to mine rocky cemented fill technology. Key words: rocky cemented fill(RCF); rock particle segregation; rock size; chute angle 地下开采中开拓,采准与切割会产生大量块石,若排至地表,将侵占土地,污染环境,成为资源开发中的一大公害.目前,我国有......
and initiation angle was acquired according to the maximum tensile failure criterion. For validating the theoretical solutions, the experimental results and the in-situ test results were compared... fracturing; perforation; stress intensity factor; break down pressure; initiation angle 水力压裂中,射孔是油气完井工程的重要组成部分,一方面,射孔连通复杂储层与井眼,能提高射孔完井的作业效率和油气产量；另一方面,能合理保护储集层,延长油气藏的开发寿命[1].但是,由于钻井过程的不确定性以及地层的复杂性,有效预测射孔破裂压力......
Impact Resistance of Reactive Powder Concrete焦楚杰1,SUN Wei21. School of Civil Engineering, Guangzhou University2. School of Materials Science and Engineering,Southeast University摘 要:The impact behaviour of three types of reactive powder concretes(RPC) was studied using the split Hopkinson press bar(SHPB) testing method. These RPC were prepared with steel......
flow rate of all schemes. And the shell side heat transfer coefficient, pressure drop and the comprehensive index ho/△po decrease with the increase of the baffle incline angle at a certain mass flow.... Key words: performance experiments; helical baffled heat exchangers; circumferential overlap of baffles; incline angle of baffle; heat transfer enhancement 1 Introduction The segmental baffled heat......
) Abstract: The effects of precipitation evolution at sub-grain boundaries on electrical conductivity and impact toughness of 7050 aluminum alloy during aging were investigated by optical microscopy, electron back scatter diffraction and transmission electron microscopy. The results show that the electrical conductivity increases and the impact energy drops due to the transformation and growth......
, the impact of hitting increases. At a normal angle, the impingement reaches maximum as there is thorough interaction between the erodent and surface. A total kinetic energy of erodent is exhausted in crater...). Deformation of the surface also takes place in erosion. Considering the limitation of applicability of cutting and deformation theories with respect to the angle impact, NEILSON and GILCHRIST[22] proposed......
Environmental impact evaluation for high-speed railwaySONG Xiao-dong(宋晓东)1, FU Yan-bing(付延冰)1, CHEN Zhi-ya(陈治亚)1, LIU Heng-bin(刘恒斌)2(1. School of Traffic and Transportation Engineering, Central South University, Changsha 410075, China;2. Transport Department, Ministry of Railway, Beijing 100844, China)Abstract:Environmental impact evaluation system boundary of high-speed railway was defined based......
Effects of Vertical Angle of Conical Punch on Stretch Flangeability of High Strength SteelYukihisa Kuriyama2,Katsuyuki Suzuk22. The University of Tokyo摘 要:To clarify the effects of the vertical angle of a conical punch on stretch flangeability, hole expansion forming tests were conducted. Test results showed that the hole expansion ratio becomes larger......
of the WMZ increases as the heat input increases. Key words: K-TIG welding; heat input; α′ phase; high-angle grain boundary; Charpy impact fracture surface 1 Introduction The Ti-6Al-4V (TC4) titanium... as the heat input increased. In previous study [4], it was found that large- angle GB had certain effect on the impact toughness of welded joints. Under certain conditions, as the proportion of high-angle......
图分类号:TG 174.443 文献标识码:A Microstructure and impact properties of slow injection A356 die castings with partial squeeze BAI Yan-fei, ZHAO Hai-dong, LI Yuan-yuan, KANG Zhi-xin (State Engineering Research Center for Metallic Materials Net-shape Processing, South China University of Technology, Guangzhou 510640, China) Abstract: The microstructures and impact properties......
