Abstract: Bubble sizes and gas hold-up are important parameters of flotation column.bubble sizes and local gas hold-up in downflow pipe of LHJ column were determined with electro-optical probe method in this paper.the affection of bubble sizes and local gas hold-up of LHJ column by column structure parameters and fluid physic-chemical parameters was investigated. The results showed that fluid pressure,radial and axial position of downflow pipe, pH and dosage of frother all have effection on the bubble sizes and local gas hold-up, and that addition of frother can obviously decrease the mean bubble size and mean while increase the gas hold-up.
Abstract: When curing time of rapid-hardening backfill materials is up to 60 days,the weathering of the materials will begin and at 90 days the weathering becomes more severe. The reasons of weathering happening are that the ettrin-gite in the backfill body is destroied by the erosion of CO2 in air, and the free water in the backfill body is dried out. An approch to keep the rapid-hardening backfill materials from weathering is to have a environment of unchanging temperature and unchanging moisture.
Abstract: The study on the bond mechanism of metallic pellet produced from Zn-Pb-bearing iron and steel plant dust with carbon shows that its compression strength is not only dependent on the shape and amount of iron phase but also on the size of hole in metallic pellet. The hole size depends on the fluidity of slag phase in pellet and its filling condition to the hole in pellet.The amount and shape of iron phase depend on the reduction degree of pellet.
Abstract: According to the coexistance theory of metallic melt structure involving compound formation,a calculating model of mass action concentrations for Fe-C-O metallic melt is formulated.Satisfactory agreement between calculated and measured value shows that this model can reflect the structural characteristics of the metallic melt.
Abstract: Optical smooth diamond films have been deposited at low temperatures (400~700℃) and their IR properties were studied for infrared optical coating applications.High density diamond nucleation was realized by a "Two Step Process" in which a high methane concentration was used for nucleation enhancement. However, biasing was shown insufficient for nucleation enhancement at low temperatures.Transmittance as high as 80% for diamond coated single crystal silicon wafer was observed.This level of IR transmission is good enough for practical applications of Si windows in a severe atmosphere.
Abstract: The mechanical activation, sintering property and alloy structure of Mo-Cu powder were studied. The experimental results showed that the lamellar structure had been obtained after ball milling, the alloy density sintered to 99% at lower LPS temperatrue,and the final structure was homogeneous with fine Mo particles.
Abstract: When Single crystal diamond was set in Fe alloys and sintered on certain condition, it was found that the diamond was etched obviouly, but the crystal structure and strength was not changed, etching was occured on the interface between diamond and binder by the dissolving and diffusing of carbon atom in diamond crystal lattice into iron. Well controlled, Fe substrate binder diamond tool could obtain good properties.
Abstract: The heat treatment dual-phase drawn steel pipes used as hydraulic cylinaer investigated. Experimental results show that heat treatment dual phase drawn steel pipes have hign strength and good ductility, hign bursting pressure as well and are better to be used as hydraulic cylinder than quenched and tempered steel pipes.
Abstract: The material in mold is melt by using induction heating and maintained a small height. Incrementally melting and solidification take place from bottom to top, by the motion between mold and heating source, reaching the molding purpose. This process can reach a near net shape and get excellent properties.
Abstract: Spray forming is a complicated process controlled by many variables. In order to control the microstructure of the spray deposited preforms to obtain the optimum properties, it is important to thoroughly understand the fundamentals of the spray forming deposition processes, and the factors of the processing parameters. In this paper, the major processes and the influential factors concerning the spray forming process as well as the results of the theoretical and experimental analyses up to now in this field were briefly reviewed.
Abstract: The influence of phase on thermal mechanical fatigue life is discussed by comparing with three different kinds of the phenomenological descriptions of the life curves which are expressed in terms of mechanical strain range Δεm, total strain range Δεt and inelastical strain range Δεin respectively. And the simplified laboratory thermal mechanical fatigue test method which is subsequently undertaken to simulate the service conditions of engineering materials and the working conditions of the turbine disk. It is show that the terms of total strain range Δεt must be used not only in test but also in phenomenological describing the life curve for thermal mechanical fatigue.
Abstract: The concept of integrated quality control system for the process of production in mordern iron and steel complex is put forward from the view of TQC,and its content are described. The integrated quality control system for the process of production is the application of CIM on the research field of quality control. The realization of integrated quality control system for the process of production based on microcomputer must be carry forward the structural optimization of Chinese iron and steel industry and improve steels quality.
Abstract: The influecing function method of separble model is used to study the rolls deformation of pair cross mill. The function relatonship between the target values (roll gap valus, sheet crown, pressure distribution, forward and backward tension lateral distrition) and adjustabll values (cross angle and bending roll fore) is established under controlling strip shape. Set of mathematical model of pair cross mill controlling strip shape is buit up.
Abstract: For planar linkages a new method of adding a fixed cam to balance the inertia input torque is presented.With this method the imput torque can be partially or complete balanced, using the moment of inertia of the mass which is added to input crank for balancing the shaking force. The main advantage of this technique is that no other mass (broad sense) needs adding to original linkage for the purpose to decrease or complete balance the fluctuating torques. But the moment of inertia of the added mass should be adjusted according to the requirement.
Abstract: The mathematical model of three-dimensional steady-state heat conduction in the contact surface between two coaxial cylindrical layers is used for analysing the effects of geometric, mechanical and thermal parameters on the contact thermal resistance.The limit value of the constriction function A is found and the influence of contact pression is studied.
Abstract: The dasic principle of direct self control system is analysed. A mixing type of flux estimator is empolyed at high and low velocities.A kind of improved flux and torque controller is presnted and the corresponding selecting rule of voltage vectors is showed at the same time.It puts forward that the control system by 8098 single chip miciroprocessor is desingned. Simulation and experimental results are showed at the end.
Abstract: The electrolyte was compelled to form turbulent flow by using speed electroplating apparatus. The Zn-Ni alloy electro-deposition law in simple sulphate system under high current density was studied. The results indicated that Zn-Ni alloy electroplating is abnormal co-deposition. The content of nickel in the deposite increases with the increase of the ratio of Ni/Ni+Zn and the current density. It decreases with the increase of the fluid speed of electrolyte. On the above basis, the technology of high speed Zn-Ni alloy electroplating has been determined.
Abstract: The Potential vs time curves of reinforcing steels embedded in fresh concrete mud containing trace amount of Cl- have been measured by galvanostatic method with anodic current density of 50μA/cm2. The effect of 7 kinds of additives (water reduced agent, fast strengthening agent, inhibits solidifing agent and high performance water reduced agent, et al) on electrochemical behavior of the embedded steels in low concentration of Cl- has been investigated. The results show that the correct and effective testing method in the Standard JC 475-92 is proved,and trace amount of Cl- is detrimental to the passivity of the steel tendon embedded in concrete. The additives tested are beneficial to inhibition the breaking up of passive film by Cl- for reinforcing steels embedded in fresh concrete mud.
Abstract: A method has been developed to produce Cu-Ni composition-modulated alloys from a simple electrolyte by electrodeposition.The effects of the concentration of copper ions,additives and the speed of rotation were investigated.The results were analysed by SEM and X-ray diffraction.The result indicated that the film was alternating pure copper and copper-nickel alloy layers.If the content of copper in nickel layer is to be small, the concentration of its ions in solution must be small and the rotation speed must be low.
Abstract: Formative position of fatigue crack, and fatigue life of asymmetric notched component are investigated.A stress field intensity function, which reflects effect of the equivalent stress at perilous point and that of the stresses and its gradient within the damage area on crack formation, is presented.
Abstract: Best approximation method of Bezier Surface is posed here. It can get the purpose by doing Least square computation finite times. The Best approximation of Bezier curves is also included.
Monthly, started in 1955 Supervising institution：Ministry of Education Sponsoring Institution：University of Science and Technology Beijing Editorial office：Editorial Department of Chinese Journal of Engineering Publisher：Science Press Chairperson：Ren-shu Yang Editor-in-Chief：Ai-xiang Wu ISSN 2095-9389CN 2095-9389
