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Chairman :KANGYi 康 义Vice Chairmen :HUANGBai yun 黄伯云NIUYin jian钮因健QIUGuan zhou 邱冠周Advisors:CHENJia yong  陈家镛HUANGPei yun  黄培云SHIChang xu  师昌绪WANDian zuo 王淀佐WEIShou kun 魏寿昆Members :CAOChu nan   曹楚南     PENGChao qun  彭超群     YANGXian wan  杨显万CHENJing  陈 景     QIUDing fan  邱定蕃     YINEn sheng  殷恩生CHENQi yuan  陈启元     QIUZhu xian 邱竹贤     ZENGSu min 曾苏民CUIKun …  相似文献   

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1 INTRODUCTIONTheimportantbacteriainbiohydrometallurgyaremainlyaerobicchemolithotrophicspecies ,ofwhichthemoreimportantareThiobacillusferrooxi dansandThiobacillusthiooxidans .ThepropertiesofthetwospeciesareshowninTable 1.Theycatalyzetheoxidationofsomeora…  相似文献   

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Experimental investigations on the DC spot welding of Mg alloy AZ31B are presented. Experiments are carried out to study the influence of spot welding parameters ( electrode force, welding heat input and welding time) on the tensile shear load and the diameter of nugget, based on an orthogonal test and analysis method. The optimum parameters are as follows: electrode force is 2 000 N, welding heat input is 80% and welding time is 6 cycles. The microstrueture of spot weld is single fine equiaxed crystals in the nugget, of which the structure is β-Mg17Al12 precipitated on α-Mg boundaries induced by nonequilibrium freezing. And the surface condition of the workpiece has great influence on the joint quality.  相似文献   

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Four Ti-C-Fe powder mixtures, with a same molar ratio but different particle sizes of Fe and Ti, were used to measure the reaction velocity of the combustion synthesis. The results show that in the case of the finer Ti powder used, the reaction velocity of mixture with the finer Fe powder is higher than that with the coarser Fe powder. However,in the case of the coarser Ti powder used, the reaction velocity of mixture with the finer Fe powder is lower than that with the coarser Fe powder. The effect of particle size of Fe powder on reaction velocity can be explained with the previously proposed mechanisms of the combustion synthesis of Ti-C-Fe system.  相似文献   

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PHASE transformation modeling is one of the mainchallenges in modeling of heat treatment[1].The mechanism of phase transformations is not fullyunderstood and interactive influence of differentelements,austenitizing temperature,etc.usually arenot taken in account.The mistakes in phase transformation calculationcould be extremely great if a model is based only ongrain size of prior austenite,austenitizing temperatureand elemental composition of steel.Phase transformation kinetic depends also o…  相似文献   

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Cyclic voltammetry, chronoamperometry and scanning electron microscopy were employed to study the influence of Zn^2 ion concentration in electrolyte solutions on zinc electroplating process. The results show that, at high overpotentials, the nucleation of zinc is instantaneous, and nuclear density increases with the overpotentials increasing. While at low overpotentials, the zinc may be preferentially electrodeposited on surface inhomogeneities such as emergence points of edge, screw dislocations, atomic disorder, kink sites, or monoatomic steps, and no distinguished nucleation current can be observed. The major dissolution peak in cyclic voltammogram drifts positively due to the change of the rate-determining step of zinc electroplating processes from diffusion to the electrochemical reaction with the increase of Zn^2 ion concentration.  相似文献   

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EditorialCommitteeofTransactionsoftheNonferrousMetalsSocietyofChina¥//Chairman:HeBoquanProfessorVice-Chairman:ChenJiayongRese...  相似文献   

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The working meeting of Composites Committee of Foundry Institution of Chinese Mechanical Engineering Society (FICMES) was held on July 25th, 2004 in Kunming, Yunnan Province. The newly elected committee members attended the meeting. The committee consists of 27 members from universities, research institutions and enterprises. The meeting was presided over by deputy-director of Composites Committee of FICMES, Prof. Ye PAN from Southeast University. He also briefly introduced the Composites Committee development amt academic activities. Prof. Shifang SU, the  相似文献   

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1. Introduction The province Key Laboratory of Special Processing of Raw Mate- rials was founded in October 2001 by uniting the Materials Elec- tromagnetic Processing & Solidification Control Institute, and Macromolecule Materials Institute. The laboratory is located at Dalian University of Technology (DUT), Dalian, China. The School of Materials Science and Engineering is the main or- ganization supporting the laboratory. It has first-class authorization spot of material science a…  相似文献   

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This article is devoted to the development of guidelines for road mapping in planning the development of the technological component of structures of national security. Making the ‘road map’ is reduced to the method of conventional optimization i.e. achievement of the target in conditions of severe limitations of existing resources taking into account the effect of controlled and uncontrolled factors. Such a result can be regarded as a scientific novelty.  相似文献   

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In 1995, the Key Lab of Liquid Structure andHeredity of Metals was set up by the approval ofShandong province, but the research work on theliquid structure and heredity of materials startedin the last three decades. In 2000, combining thelab of engineering ceramic and the institute ofjoining technology in Shandong University, thelab was established as Key Lab of LiquidStructure and Heredity of Materials, by theapproval of the Ministry of Education.Currently, prof. Zhuangqi HU, prominen…  相似文献   

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Elastic modulus is an important physical parameter of molding sand; it is closely connected with molding sand's properties. Based on theories of rheology and molding sand microdeformation, elastic modulus of molding sand was measured and investigated using the intelligent molding sand multi-property tester developed by ourselves. The measuring principle was introduced. Effects of bentonite percentage and compactibility of the molding sand were experimentally studied. Furthermore, the essential viscoelastic nature of green sand was analyzed. It is considered that viscoelastic deformation of molding sand consists mainly of that of Kelvin Body of clay membrane, and elastic modulus of molding sand depends mainly on that of Kelvin Body which is the elastic component of clay membrane between sands. Elastic modulus can be adopted as one of the property parameters, and can be employed to evaluate the viscoelastic properties of molding sand.  相似文献   

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Transactions of Nonferrous Metals Society of China   总被引:4,自引:0,他引:4  
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<正>Chief editor: HUANG Bai-yun, member of the Chinese Academy of EngineeringThe Transactions of Nonferrous Metals Society of China, mainly publishes original research andreview articles in the field of nonferrous  相似文献   

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During bio-oxidation of sulfides, the chemical state change of sulfur is a complex and key factor. It is not only an indicator of the extent and intensity of the bio-oxidation, but also controls the property of bio-leaching medium and the period of oxidation. The chemical state of sulfur in sulfides oxidized by leaching bacteria was studied with XPS. Sulfide minerals in the arsenic-bearing gold concentrate consist of pyrite, arsenopyrite, chalcopyrite, galena, sphalerite and so on. In order to probe the pattern of the chemical state change of sulfur in the bio-oxidation residue of arsenic-bearing gold concentrate, the structure of the grains, and the surface nature of the residue, XPS test was carried out through different sputtering duration. The study of XPS clearly shows that: sulfides is progressively oxidized from the surface of minerals to the core by leaching bacteria; the chemical valence of sulfur changes from S^2- or [S2]^2- to [SO4]^2- ; sulfur in the core is in a reduction state, S^2- or [S2]^2- , but exists in an oxidation state S^6 on the surface; due to the chemical state change of sulfur, mineral phase of the bio-oxidation residue is also changed(sulfides inside, while sulfates outside); the layered structure is found in the grains of the bio-oxidation residue.  相似文献   

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Based on the principle of annexation and phase diagrams, the structural units of In-Pb-Sb and In-Bi-Pb melts were determined, and their calculating models of mass action concentrations were formulated. Calculated results agree well with practical values, which in turn show that the models deduced can reflect the structural realities of corresponding melts and the principle of annexation is applicable not only to some binary metallic melts, but also to ternary metallic melts.  相似文献   

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