Abstract: The dispersion behaviors of solid particles of silica, calcite, talc and graphite in water, ethanol and kerosene media and the effect of certain surfactants such as sodium oleate on the dispersion behavior have been studied. It was found that hydrophilic particles, such as silica and calcitc particles, which have naturally hydrophilic surface and manifest good dispersion behavior in water at suitable pH. tend to aggregate in kerosene; while the naturally hydrophobic talc and graphite particles, generally having a tendency to aggregate in water, disperse well in kersene. It was discovered that dispersion behavior of the particles in the mixture of water and ethanol are much better than separately in water or in pure ethanol media, the maximum dispersion occurs in the mixture of water and etlianol with ratio 1:1.The effect of surfacianus is completely opposite in water and kerosene. Furthermore, in kerosene media the dispersion behavior of particles fluctuates periodically with the increase of surfactant concentration.
Abstract: The dispersion behavior of different particles in aqueous media and the influence of dispersant to their dispersion actions were studied. The results represent that dispersant shows different extent of dispersion actions to silica,calcium carbonate, talc and graphite. In the low concentration area of dispersant, the dispersion rules of these four particles are similar, whereas in the high concentration area,the dispersion of these particles has their respective characteristics. The dispersion actions of dispersant to calcium carbonate and talc are stronger than to silica and graphite. As to the same kind of mineral particles, the dispersion actions of dispersant to hydrophilic particles are stronger than to hydrophobic ones.
Abstract: Processing parameters during the preparation of ultra-fine calcinated coal kaolin powder were studied by using wet stirred mill. The results show that grinding concentration, time, the content and charge ratio of grinding media, stirring velocity of peddler are the important processing parameters of preparing ultra-fine calcinated coal kaolin powder. When the feed particle size is 100% minus 10 μm, ultra-fine powder which the particle size distribution is 95.5% under 2 μm, d50 0.97 μm is acquired by optimizing the processing parameters of stirred mill.
Abstract: On the basis of actual parameter of wall control blast in Nanfeng mine, China, the process of dynamic stress changing between two column charges was studied for the presplit-cushion blast by a recent holographic photoelasticity. In the experiment model, two holes are simultaneously detonated from both ends (four ignition points), the bottom of the holes are loaded more than other parts (heavy charge). Under the condition, four consecutive isochromatic fringe patterns at different time are aquired in one loading run. characterstics of the stress distributions are compared at different place and time in the holes. It is found that interaction types of stress wave are various along the holes. The stress wave which is formed by the interaction of earlier producing P wave and later S wave along a distributed line charge is most important part in all stress waves. Research indicates that heavy charge in the bottom of the holes is crucial to produce pres-plit-cushion effect of the bottom, "End Effect" doesn't affectt on strength of stress along linking line between the bottoms. chief field of the "End Effect" are also explained.
Abstract: Based on experimental results, it shows that the foaming behaviours occurred in metallurgical melts is similar to that taken place in aqueous solution. There are two types of foam structure, spherical foam and polyhedral foam, in the bath-smelting processes and the foaming process of Al alloy melt. Foams with large bubbles, generated by argon gas injection into liquid slag with a mon-orifice nozzle, have polyhedral bubble cells and the foamability of slag is affected by the gas injection rate and container scale besides the surface tension and the viscosity of slag. Foams with fine bubbles, generated by slag/metal interfacial reaction in the bath-smelting prcx^ess or the decomposition of TiH2 in molten Al alloy, have spherical bubble cells in the initial foaming stage and the translation from spherical bubble structure into polyhedral bubble structure takes place at the end of foaming process. Under conditions of gas evolution due to chemical reaction in melts, the foam stability is strongly affected by the rate of gas evolution, the size of bubbles and the fluid flow form besides the physico-chemicaJ properties of melts.
Abstract: The relation between the shear stress and shear rate in the Newtonian law was shown by the relation between the stirring torque and revolution through the theoretical analysis. By means of the relation between the stirring torque and the revoludon,not only the rheological characteristic of the molten A1 alloy can be identified, but also the effect of the increasing viscosity can be determined. The method for the producing porous A1 can be conveniently controlled.
Abstract: The nitride capacities of fluxes were detemined by application of platinum crucible.The nitride capacities of slag No. 1(10CaO-33BaO-49Al2O3-8TiO2) and slag No.2(54CaO-21Al2O3-6MgO-6SiO2-13CaF2) are respectively the orders of 10-6 and 10-5 under the condition of atmosphere. The nitrogen distribution ratio between steel and the slag No. 2 was determined by application of MgO crucible.
Abstract: Characteristics of crane operation in steel plant was analysed hy using relevant knowledge of loading and unloading in logistics. Function and role of transport in modem manufacturing route was summed up. And on the bases of time factor analysis and production technology research, important role of crane schedule in optimizing mass flow control of steel plant has been deduced.
Abstract: The metallurgical bonding of mother sheet and growth layer in inversion casting was investigated in laboratory. The effect factors of bonding were analyzed. The conclusions are, mother sheet can stably bond with growth layer; bonding condition is the surface of mother sheet melted; superheat of melt effect on metallurgical bonding of mother sheet and growth layer.
Abstract: The effect of the amount of Zirconia additive upon the conductivity and thermal shock resistance for Laβ-Al2O3solid electrolyte was studied. The experimental results showed that addition of Zirconia causes the decrease of conductivity and increase the thermal shock resistance of Laβ-Al2O3 solid electrolyte. Owing to the effect of two sides, the optimum content of additives is 10%.
Abstract: A new type SO2 sensor is constituted by using both NASICON and YSZ electrolytes with Na2SO4 auxiliary electrodc.lt is shown that the response of sensor to SO, is Nemstian response. As the sensor is a planar construction and both electrodes are exposed to the same test gas, there is no any need for a separate reference compartment and the effect of O2 on EMF can be eliminated. It becomes easy that sensor is miniatur-ized and incoporated on the same substrate for sensing several compenents simultaneously. KEY WORDS SO, sensor;NASICON; YSZ solid electrolyte
Abstract: Analytical model for axial symmetrical functionally graded materials(FGM) is established based on the elasticity theory and computational mathematical model. The boundary conditions of the model is determined according to its application background. Triangle series are employed to describe the thermal stress caused by the difference of thermal expansion coefficients. Thus the accurate stress distribution has been calculated.
Abstract: The analysis model used for calculation of thermal stress in FGM is estab-lisd based on, The classical lamination theory and thermal-elastic mechanics with five assumptions. The distributions of temperature and thermal stress in FGM under steady state temperatue field are derived. By means of FGM and combination with Visual Basic for Window, FGMCAD is established. The optimum distribution of thermal stress in FGM can he realized by any the relative parameters with FGMCAD, thus the optimum parameters of FGM design are determined.
Abstract: Structure and magnetism of the R3(Fe, M)29 and R(Fe, M)12 compounds derived from RT5 with CaCu5 -type structure (R=rare earth, T=Fe, and M=stable element) and the relationship between them are summarized. The influence of the stable elements and interstitial atoms(N, C and H)on the structure and magnetism of the R3(Fe, M)29 and R(Fe, M)12 compounds are reviewed.
Abstract: The effects of Dy and Nb substitution on the formation, microstructrure and magnetic properties of Pr2Fe14B/α-Fe nanocomposites have been investigated. It was found that for Pr9Fe85B6 ribbons, the metastable Pr2Fe23B3 phase occurs after the initial crys. tallization of a-Fe and prior to the formation of the finial mixture of Pr2Fe14B and α-Fe. However, no metastable phase was observed during the crystallization of Dy or both Dy and Nb substituted ribbons. The addition of both Dy and Nb can cause the significant improvement of the magnetic properties.
Abstract: The representations of magneto-calorific power P for composite wire of magnetic core with conductive layer in various shapes (columnar, tubular and sheet) are derived. The results showed that the eddy calorific power can be divided into two parts. One is relative to magnetism, electricity and the size of sample, another is relative to the adapted structure of magnetic core and conductive layer (structure factor Ψ), and to sample shape (shape factor η).The analysis indicates that the thinner the covered conductive layer is^the greater the calorific power generated by the conductor gets.
Abstract: The Al2O3/20%Al2O3(nm) + 20%ZrO2 + 60% Al2O3(μm)/Al2O3 laminated ceramic composites were fabricated by high-shear two-roll milling process. Its mechanical properties were measured and compared with Al2O3 and ZrO2 + Al2O3 non-laminated ceram-ics. The results showed that the toughness is great improved by means of laminated composite.The microcracks and tolerant of main crack propagation are the reasons to improved the toughness of laminated ceramic composites.
Abstract: The fractal dimensions of zirconia phase were measured using the techniques of quantitative metallography under different conditions:the different percentage of zirconia,sintering temperature and sintering time. The results showed that the morphology of zirconia phase and grain growth of zirconia are described well by fractals and the mechanical properties of the composites were well correlated with the fractals of the zirconia phase distribution. So, the influence of the zirconia phase on the mechanical property can be quantitatively described by the fractal dimension.
Abstract: Based on the experiment of decompostion dynamics of andalusite, the frac-tal dimensions of the decomposed grains have been measured by means of the perime-ter-area mathod. The reaction mechanisium has also been discussed with the relation ofthe fractal dimension and the reation time.
Abstract: Based on the simulation of the influence of the two-roll cross-rolling elonga-tion parameters on metal flow, the diagnosis rules which to ensure the rolling process to be carried out successfully are set up. And the optimization rules are also set up in order to improve the rolling productivity and to optimize the metal flow. The diagnosis and opti-mization system has been implemented on personal computer.
Abstract: Discusses the stability of semilinar stochastic evolution equations on Hilbert Space dY(t)=[AY(t) +f(Y(t))]dt + G(Y(t))dw(t). At first, in order to Study Stochatic asymp-totically stability, some concepts for mild-solution,, and the sufficiently conditions for this stability are obtained. Secondly, some new concepts of stability are defined. The main results make the finite dimensions extention and Ichika' results development.
Abstract: The hot rolling of steel plate was studied with the aid of elastic-plastic and thermal-mechanical coupled FEM, particular attention was paid to predict the tempera-ture distribution through the thickness of rolled plate. The influences of heat transfer model and variation of roll temperature on calculated result were analyzed. Comparison of the calculated results with those from experiment showed good agreement.
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
