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Desulfurization of Nickel Pyrrhotite by Steam in the Microwave Field

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Journal of Materials science & technology 2001年第5期17卷 561-564页

作者： Jinhui PENG and Chunpeng LIU Department of Metallurgy, kunming university of science and technology, kunming 650093, China kunming univ sci & technol Dept Met Kunming 650093 Peoples R China

Desulfurization of Ni pyrrhotite by steam in the microwave field was studied. According to the experimental data, the desulfurization rate by microwave heating is faster than that by conventional one. The desulfurization reaction is in a non-isothermal state and in a diffusion control because of the effect of chemical reaction heat, phase formation and intrinsic properties of materials of microwave absorbability. When the flow rate of steam was in the range of 180 similar to 220 mL/min, the temperature and desulfurization rate approached to a maximum and the activation energy to a minimum.

关键词： Ni Desulfurization of Nickel Pyrrhotite by Steam in the Microwave Field

Evaporation Kinetics of SnS from SnS-Cu_2S Melts

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Journal of Materials science & technology 1998年第1期14卷 45-48页

作者： Yixin HUA and Chunpeng LIU (Dept. of Metallurgy, kunming university of science and technology, kunming 650093, China) kunming univ sci & technol Dept Met Kunming 650093 Peoples R China

The kinetics of SnS evaporation from SnS-Cu2S melts was investigated by a unique experimental method. It is shown that the process is controlled by the mass transport of SnS in gas phase. The evaporation rate of SnS is significantly enhanced by increasing tempeature and carrier gas flow rate. The apparent activation energy for the process is found to be 204.67 kJ. The evaporation rate for the present system is much smaller than that for SnS-FeS system.

关键词： SnS Cu Evaporation Kinetics of SnS from SnS-Cu2S Melts

Microstructure of electrodeposited RE-Ni-W-P-SiC composite coating

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中国有色金属学会会刊：英文版 2000年第1期10卷 50-52页

作者：郭忠诚朱诚意翟大成杨显万 kunming univ sci & technol Dept Met Kunming 650093 Peoples R China

The components and microstructure of the RE Ni W P SiC composite coating were analyzed by means of EPXDS, SEM and XRD. The results showed that the composite coating containing 5%～14%RE, 4%～7%SiC, 12%～15%P and 5%～6%W was obtained by use of appropriate bath composition and plating conditions. The as deposited composite coating is amorphous and it becomes mixture when the temperature is raised from 200 ℃ to 400 ℃. However, the composite coating is crystal when the temperature is over 400 ℃. Scanning electron microscopy indicates that the heat treatment temperature has no effect on the surface morphologies of the RE Ni W P SiC composite coating. This is to say that the composite coating has a better heat stability of microstructure and high temperature oxidation.

关键词： electrodeposition RE Ni W P SiC composite coating microstructure

ANALYSIS OF STABILITY CHARACTERISTICS OF NONLINEAR FLUID STRUCTURE INTERACTION SYSTEM IN INTERNAL FLOWS

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Journal of Hydrodynamics 2001年第2期13卷 96-105页

作者： Zhang, L.X. Huang, W.H. Li, J.B. kunming univ. of sci. and technol. Kunming 650051 China

A set of nonlinear partial differential equations was used to describe the motions of an internal flowing system, with the consideration of transient fluid structure interaction (FSI). The stability characteristics of the system were analyzed on the basis of the nonlinear FSI-equation model. The results show that the stability of the nonlinear FSI system become very complicated because of the influence of strongly coupled interaction between flowing liquid and vibrating pipe. The flowing velocity, pressure, the piping stiffness, and constrained conditions, etc. play a very important role in developing procedure of the system stabilization. In an analysis example given in this paper, for example, when the flowing pressure is comparatively small, the system exhibits flutter instability, and when the flowing pressure is increases to a specified value, a subcritical divergence and a supercritical flutter bifurcation take successively place in the same velocity range.

关键词： Bifurcation (mathematics) Differential equations Equations of motion Flow interactions Vibrations (mechanical)

Preparation and Corrosion Resistance of Silicate Passivation Film Formed on Galvanized Zn Coatings

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稀有金属材料与工程 2012年第S1期41卷 211-214页

作者： Fan Yunying Jiang Yehua Li Zulai kunming univ sci & technol Kunming 650093 Peoples R China

In this paper,one kind of silicate passivation technics was reported and by which method silicate passivation film on galvanized Zn coatings with satisfactory property was *** coatings were prepared by conventional plating *** solution composition and operating conditions of passivation are:sodium silicate 10-30 g/L,H2SO4 5 mL/L,HNO3 5 mL/L,H2O2 5-20 mL/L,pH 1.5-2.5,passivation time 5-30 s,temperature 25℃.The corrosion resistance of galvanized Zn coatings with different passivated technics were investigated by NSS corrosion test and compared with Zn coatings treated by Cr(VI)and Cr(III).The silicate passivation film can keep no rust for 72 h and obviously shows the best *** morphologies of galvanized Zn coatings with different passivated method were got by metallurgical microscopy,and the silicate passivation film shows the most uniform surface,and has the least *** the results show that silicate passivation technics can provide galvanized Zn coatings superior anti-corrosion performance and simultaneously avoid the pollution of chromium,so this technology has a wide application in future.

关键词： galvanized Zn coating silicate conversion film corrosion resistance

RESEARCH ON SYNCHRONOUS DOUBLESOLITON ON HELICAL CHAIN MODEL OFTHE α-HELIX PROTEIN

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Acta Mathematica scientia 1999年第3期19卷 307-314页

作者：吴光敏雷玉明周熠颖周凌云 kunming univ sci & technol Res Ctr Nonlinear Sci Kunming 650093 Peoples R China

Increase a degree of freedom for one dimension dynamical system of the α-helix protein, obtaining the dynamical system model of double degree of freedom. In this new dynamical system there are the solution of double soliton on the polypeptide chain of α-helix protein, and the coupling intensity of the double soliton relate obviously with their center distance. The solution of the synchronous double soliton has been studied by the analytical method for two cases of the stronger and weaker coupling. The possible effect brought by tile double soliton for the protein property has been discussed.

关键词： α-helix protein degree of freedom soliton

Corrosion resistance of electrodeposited RE-Ni-W-P-SiC composite coating

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中国有色金属学会会刊：英文版 2001年第3期11卷 413-416页

作者：郭忠诚朱晓云杨显万 kunming univ sci & technol Sch Mat & Met Engn Kunming 650093 Peoples R China

Immersion experiment results show that corrosion rate of the as deposited RE Ni W P SiC composite coating in HCl solutions increases with the rise of HCl concentration. On the contrary, the corrosion rate of the composite coating after heat treatment decreases with increasing HCl concentration. The corrosion rates of the composite coatings in as deposited state and after heat treatment in H 2SO 4 and H 3PO 4 solutions respectively decrease with the rise of H 2SO 4 and H 3PO 4 concentrations. The corrosion rate of the composite coating as deposited in FeCl 3 solutions decreases with increasing FeCl 3 concentration, while the rate of the composite coating after heat treatment increases with the rise of FeCl 3 concentration. The corrosion rate of 316L stainless steel in the corrosion media of H 2SO 4, HCl, H 3PO 4 and FeCl 3 solutions at different concentrations increases with rising concentration. In addition, the corrosion rate of 316L stainless steel in the corrosion media of H 2SO 4, HCl, H 3PO 4 and FeCl 3 solutions respectively is much greater than that of the RE Ni W P SiC composite coating as deposited and after heat treatment in the same corrosion media. [

关键词： corrosion resistance RE Ni W P SiC composite coating electrodeposition

Structure and characteristics of electrodeposited RE-Ni-W-P-B_4C-PTFE composite coatings

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中国有色金属学会会刊：英文版 2001年第6期11卷 887-890页

作者：陈凌郭忠诚杨显万 kunming univ sci & technol Fac Mat & Met Engn Kunming 650093 Peoples R China

Hardness, friction and wear characteristics of electrodeposited RE Ni W P B 4C PTFE composite coatings were studied, and the reason for these fine characteristics was explained in respect of structure. The results show that 1) the structure of RE Ni W P B 4C PTFE composite coatings experiences a transformation process from amorphous to mixture then to crystal as the heat treatment temperature rises; 2) incorporating of B 4C greatly increases the hardness of the coating; 3) the wear resistance of the coating is best with heat treatment for 1?h at 300?℃, which is greatly superior to that of the other traditional coatings.

关键词： electrodeposited RE Ni W P B 4C PTFE composite coatings structure hardness wear resistance

Effects of addition of rare earth on properties and structures of Ni-W-B-SiC composite coatings

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中国有色金属学会会刊：英文版 2000年第4期10卷 538-541页

作者：郭忠诚翟大成杨显万 kunming univ sci & technol Dept Met Kunming 650093 Peoples R China

The effects of rare earth (RE) on the composition, phase structures, surface morphologies and hardness of electrodeposited RE Ni W B SiC composite coatings were discussed. The results show that W and SiC contents in the coatings increase with the increase of RE in the bath. When RE is added in the coatings, the grains are refined and the trend of formation of amorphous coatings is increased. Moreover, the thermal stability of the RE Ni W B SiC composite coatings is enhanced. The hardness of the coatings is increased with the increase of heat treatment temperature, and it reaches the peak value when heated at 400 ℃. Besides, the hardness of the RE Ni W B SiC coatings is higher than that of the Ni W B SiC coatings.

关键词： RE Ni W B SiC composite coating properties electrodeposition