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Dynamic phase-mining optimization in open-pit metal mines GU Xiao-wei(顾晓薇), WANG Qing(王 青), GE Shu(葛 舒) College of Resource and Civil Engineering, Northeastern University, Shenyang 110004, China... and practical. 2 Generation of geologically optimum pits A "geologically optimum" pit for a given total tonnage (ore plus waste), T, is the pit that contains the maximum metal quantity of all the pits......
of dielectric loss and magnetic loss. Key words: microwave absorption; La0.8Ba0.2MnO3; nickel; nano-composite materials; dielectric loss; magnetic loss ... of loss factor tan δ of sample W3 with microwave frequency 2.3 损耗机制分析 图7所示为样品W3在微波波段的介电谱,其中为介电常数的实部,为介电常数的虚部.可见,介电常数的虚部在11.1 GHz出现峰值,电介质理论表明此峰值主要是由于介电弛豫极化引起的极化损耗 峰[14].Ivanov等[15......
characteristics and the structure flow theory. Through analyzing the resistance loss of the pipeline and force condition of the elbow under different concentrations and volume fluxs, the best transportation... density filling with coarse aggregates in mine. Key words: waste rock-tailing; Fluent numerical simulation; gravity transportation; pipeline resistance loss 高浓度充填是近几十年来充填研究的主要方向,高浓度料浆具备不离析,不沉淀,充填质量好,效......
alkali-metal oxides and the physical properties of the glasses such as thermal expansion coefficient, electric resistivity and dielectric loss were discussed. The results show that K2O has less effect... of alkali-earth metal ions. The glasses have high electric resistivity but low dielectric loss when the mole ratio of Na+ to K+ is about 2?1. The lead free infrared absorbing sealing glass matching alloy......
stope over-excavation and under-excavation, stope dilution and ore loss rates, and the blasting design of the pillar with complicated irregular boundaries were developed. These techniques were applied...%, 12.67% and 10.68%, respectively, and the ore loss rates of stopes 52-6# and 52-8# are 4.41% and 3.70%, severally. Furthermore, according to the design accomplished by the technique for a pillar......
technique. Metal release and weight loss from 17-4 PH stainless steel foams were investigated in fluoride added artificial saliva environment by static immersion test.An inductively coupled plasma-mass spectrometer was employed to measure the concentrations of various metal ions.Effects of fluoride content of artificial saliva on metal release and weight loss from the steel foams were......
依靠现代技术提升首饰加工产业袁军平1,王昶1,郭文显1,申柯娅1,陈令霞1,代司晖1(1.广东省广州市番禺区广州番禺职业技术学院珠宝学院)摘 要:分析了当前首饰加工企业面临的用工成本增加,允许金耗降低,原材料价格高涨,加工费利润微薄,环保压力加大等诸多严峻挑战,提出了首饰加工企业要积极运用现代先进工艺技术,加快转变传统生产方式.文中以快速成型技术的应用,先进金属材料的应用,蜡镶铸造技术的应用,新型打磨抛光技术的应用以及建立全面的废料回收系统等5个方面,阐述了首饰加工企业实现高效率,低损耗及清洁生产的技术途径.<......
Trans. Nonferrous Met. Soc. China 20(2010) s852-s856 Wear of semi-solid rheocast SiCp/Al metal matrix composites U. A. CURLE, L. IVANCHEV Materials Science and Manufacturing, Council...% (volume fractions) exhibits the capability of the council for scientific and industrial research-rheocasting system(CSIR-RCS) in rheo-processing and high pressure die casting of SiC metal matrix......
J. Cent. South Univ. (2021) 28: 1357-1376 DOI: https://doi.org/10.1007/s11771-020-4537-1 Precision loss of ball screw mechanism under sliding-rolling mixed motion behavior QI Bao-bao(齐宝宝)1, 2... mixed motion behavior degrades the ball screw’s precision at different levels. Based on the sliding-rolling mixed motion between ball and screw/nut raceway, the ball screw’s precision loss considering......
Effect of copper impurity on the optical loss and Nd3+ nonradiative energy loss of Nd-doped phosphate laser glass徐永春,李顺光,胡丽丽,陈伟Shanghai Institute of Optics & Fine Mechanics, Chinese Academy of Sciences摘 要:N31-type phosphate laser glasses doped with different concentrations of Cu were prepared. Their optical loss coefficient at 1053 nm wavelength......
