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71.
P. Zou* W.B. Zhang Kunming University of Science Technology Kunming China T. Lei J.K. Wang Technology Center Yunnan Metallurgy Group Co. Ltd. Kunming China 《金属学报(英文版)》2006,(5)
1. Introduction There have been two difficulties encountered with the leaching of low-grade primary chalcopyrite oresusingmesophile culture-thiobacillusferrooxidans(Tf) and thiobacillusthiooxidans(Tt), and so on[1-3].The first is the poor leaching effect and the second is the resultant increase in temperature during the middle and the later phase ofheap-leachingperiod, which is unfavorable for the growth and the culture of Tf and Tt. Being widely used for mineral leaching at present, Tf and … 相似文献
72.
73.
Sn-Sb peritectic alloy was treated with 400 W, 600 W and 800 W ultrasonic, respectively, to study the effect of power ultrasonic on solidification microstructure. Results show that power ultrasonic can refine α phase and β phase of the alloy, as well as eliminate gravitational segregation. Moreover, 600 W ultrasonic demonstrated the best refining effect, not only homogenous and fine solidification microstructure can be obtained, the cubical β phase crystals can also be spheroidized. 相似文献
74.
C.F. Yu* Deptartment of Physics College of Science Xi''''an Polytechnic University Xi''''an China K. Yan Xi''''an Modern Nonlinear Science Applying Institute Xi''''an China D.Z. Liu Section Second Artillery Institute of Engineering Xi''''an China 《金属学报(英文版)》2006,19(6):455-468
Using a field equation with a phase factor, a universal analytic potential-energy function applied to the interactions between diatoms or molecules is derived, and five kinds of potential curves of common shapes are obtained adjusting the phase factors. The linear thermal expansion coefficients and Young‘s moduli of eleven kinds of fuce-centered cubic (fcc) metals - Al, Cu, Ag, etc. Are calculated using the potential-energy function; the computational results are quite consistent with experimental values. Moreover, an analytic relation between the linear thermal expansion coefficients and Young‘s moduli of fcc metals is given using the potential-energy function. Finally, the force constants of fifty-five kinds of diatomic moleculars with low excitation state are computed using this theory, and they are quite consistent with RKR (Rydberg-Klein-Rees) experimental values. 相似文献
75.
ZENG Ai-xiang w XIONG Wei-hao * . Department of Chemistry Changsha University of Science Technology Changsha China . State Kay Laboratory of Die &Mould Technology Huazhong University of Science Technology Wuhan China 《材料热处理学报》2004,25(5)
FLY ASH CENOSPHERES are primarily a by-productin power generation plants.Research is in progress toeffectively use this by-product to produce new usableand profitable materials as they pose major disposaland environmental problems.Fly ash cenospheres areunique,property stable,non-toxic,non-metallic hollowmicro-particles.Due to the unique hollow structure andphysical mechanics properties,Cu^Ag and other metalsare often coated on cenospheres to produce lightweightmetal matrix composites,w… 相似文献
76.
Tensile testing results of spray cast Ni3Al-based superalloy indicated that the yield strength and tensile strength increase with the increasing of temperature and reached maximum at around 760℃, then decrease with the increasing of temperature. After high temperature isostatic pressing (HIP), yield strength decreased and ductility and tensile strength increased. Stereographic projection showed that no matter at room temperature, medium temperature or high temperature, cracks extend along (111). 相似文献
77.
INFLUENCES OF TRACE ADDITIONS OF STRONTIUM AND PHOSPHORUS ON ELECTRICAL RESISTIVITY AND VISCOSITY OF LIQUID Al-Si ALLOYS 总被引:1,自引:0,他引:1
Gui Manchang Jia Jun * Li Qingchun * Guo Wenquan Institute of Aeronautical Materials Beijing * Harbin Institute of Technology Harbin Institute of Metal Research Chinese Academy of Sciences Shenyang 《中国有色金属学会会刊》1997,(4)
INFLUENCESOFTRACEADDITIONSOFSTRONTIUMANDPHOSPHORUSONELECTRICALRESISTIVITYANDVISCOSITYOFLIQUIDAlSiALLOYS①GuiManchang,JiaJun,... 相似文献
78.
A typical hot concentrated alkaline corrosion environment exists in alumina metallurgical industry, so that steel materials with outstanding alkaline corrosion resistance are strongly demanded for its processing equipment. In this paper, the corrosion resistance of two kinds of martensitic cast steels containing chromium in static 303g/L NaOH alkaline solution at 85℃ was studied through polarization and potential-time curves, corrosion weight loss and corrosion morphology analysis. Experimental results showed that protection effect by passive film of cast steel containing Cr was temporary. The low carbon steel without Cr content also exhibited chemical passivity in the same solution. The corrosion mode of the tested Cr-containing cast steel was composed of active dissolving corrosion and caustic embrittlement cracking. Dissolving corrosion was the primary mechanism for the induced weight loss, while severe caustic embrittlement cracking was secondary. With the increase of chromium content in the cast steel, the tendency of the caustic embrittlement cracking decreased, while the active dissolving corrosion increased. 相似文献
79.
Reaction of (C_5H_5)_2NdCl·2LiCl with n-Butyllithium: Formation and Crystal Structure of [Li(DME)_3][(C_5H_5)_3Nd(μ-H)Nd(C_5H_5)_3] 相似文献
80.
Effects of Cerium on Rooting and Physiological-Biochemical Metabolism of Tissue Culture Plantlet from Dioscorea Zingberensis 相似文献