Continuous detection of temporal changes of liquid hold up, which is regarded as an important factor in grasping fluidzing states of gas-liquid mixed-phase flow, was made by means of electrical conductivity measurements. On the basis of the experimental data, present authors succeeded to obtain the empirical equations relating hold up with conductivity satsfactorily. With regards to apparent conductivity of dispersed systems the equations of Maxwell, of Bruggeman and of Rayleigh should be firstly mentioned. However these seem to be applicable to the case of gas liquid mixed phase flow over the limited range of liquid hold up from 0.9 to 1.0 It is obvious that authors' equations, because of their wider applrcabrlrty to the change of hold up, are more convenient than the equations above mentioned.
Moreover, by use of these equations it was attempted to control liquid hold up under fluidized condition of gas liquid mixed phase and the satisfactory controlling was rendered to be possible.

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The growth rates of single crystal particle from the melts, which form simple eutectic compounds, were measured and were analyzed as the simultaneous heat and mass transfer phenomena with a surface reaction. The empirical correlations of both heat and mass transfer rates obtained from the dissolution rates of crystals agreed well with those of the transfer rates from single particle The rate constants of the surface reaction expressed in Arrhenius' equation were about the same order of magnitude with those in the crystallization from aqueous solutions.
These experimental results showed that the greater growth rate of crystals from a melt than from a solution was due to the high concentration of mother liquid The effect of the heat transfer rate on the growth rate was very large especially when the concentration of mother liquid was very high, and almost negligibly small for low concentration of mother liquid.

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To obtain the kinetic parameters of the single reaction from the data in nonrsothermal experiments, the theoretical method named here “Effective temper ature method” was proposed This method was ap proved to give the satisfactory results, for example by treating the pyrolysis data of the low molecular hydrocarbons
The extention of this method was tried to the complex reactions and it was found by the digital com putor calculations of the model reactions that the results obtained under the adequately selected conditions were good enough for approximate estrmation.

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In order to clarify the behavior of the swarm of bubbles in fluidized bed, the equations for estimating the diameter of bubble formed on the perforated or porous plates are presented and a model representing the behavior of bubbles which takes place during the approach of two bubbles and predicting the location of their coalescence is developed Furthermore, this model is extended to the model describing the behavior of swarm of bubbles in the bed.
Both the longitudinal and radial distributions of the swarm of bubbles and their coalescence have been evaluated from the model with the and of digital computer. From the results of the analysis concern g the effects of gas velocity, diameter of ibned and the kind of distributor on the coalescence of bubbles and on their distribution, it has been found that the behavior of the swarm of bubbles can be explained satisfactorily by the model given in this paper

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The following assumptions were made concerning packing mechanism in order to derive the equation of packing volume.
“The voids between coarser particles are filled with finer particles with the definite packing efficiency. Further the residual voids are filled preferentially with still finer particles with the definite packing efficiency.”
The packing volume were calculated according to the derived equation containing three variables: the apparent volume of each component, mixing ratio of the components, and the packing efficiency data ex perimentally obtained for all combination of two components.
In case of three, four and five components systems of roseks grading aggregates, the calculated apparent volumes were in good agreement with the experimental data.

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The authors have proposed the following equation as an expression for the specific surface increase ΔS_z after z revolutions have been applied in the Hardgrove grindabilrty machine.
where z is total number of revolutions, z characteristic value of z, ρ true density, and y is the coefficient defined by the following equations
where P is applied compressive load, V_t true volume of particles composing the powdery sample, and CEI is the crushing extension index.

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The authors have proposed the following Eqs.(1) and (2) as the basic relations between the load P and the displacement Δl on the slow compression packing and crushing of powdery layers in the mortar, and have proposed Eq (3) as the relation between the net work input to crushing A_rp and the crushing conditions, and then confirmed that these relations are in fairly good agreement with the corresponding experimental results.
(1)
P/F=α·∅(2)
(3)
where Δl is the displacement of powdery layers under the pressure P, Δl_∞t hat in the case P=∞, the apparent strain defined by Eq.(1), F cross sectional area of mortar, α proportional coefficient, V_∞ true volume of particles composing the powdery layers, and ε₀ the porosity of powdery layers in the case P=0.

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Mixing time and power consumption of several types of impellers were studied. For the mixing of highly viscous non-Newtonian liquids, impellers such as ribbon and screw with the draft tube with which the liquid was forced to circulate throughout the vessel, were proved to be good Ribbon, ribbon combined with screw, half ellipsoidal blade impeller with the draft tube, and screw with the draft tube were observed to be good for the mixing of non-Newtonian liquids. Up-down mixers developed by the authors showed a good mixing performance.
Combining a helical screw on the shaft of ribbon impeller, mixing efficiency can be improved, in spite of the increase in power consumption is not so considerable. However, when the volumetric discharge rate exerted by the screw is less than that of ribbon, the introduction of the screw on the shaft gives lower mixing efficiency.
It was also revealed in this experiment that a double helical ribbon with pitch 1.0 was most efficient among various impellers tested and showed no dead space.

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Solubility curve and tie-lines were determined for the systems acetic acrd+water+n-butanol and acetic acrd+water+isoamyl alcohol at 25°C.
The plait point was located by the method of Treybal, Weber and Daley.
The concentrations of acetic acid in equilibrium layers were well correlated to nearly the plait point by Hand's plots and/or Hirata's plots.
A new correlation method was proposed by the following plots log (y_ω/x_ω)(y_ω/z_c) where x_ω is wt. fraction of acetic acid in alcohol layer, yω is wt. fraction of acetic acid in water layer and z_c rs wt. fraction of acetic acid at plait point.
Appling the method for these systems, the data on tie lines were represented by a linear correlation line for the lower concentration region below yω/z_c=0.7.

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Surface tensions at room temperature and boiling point were measured for acetic acid-water and formic acid water systems by a tensiometer of bubbling method. The surface tension measurement was carried out also for the aqueous solutions with the surface active agent of non-ionic fluorocarbon.
It was found that the values of surface tension obtained by the bubbling method are quite different from the ones by du Nouy method in the measurement for aqueous solutions with surface active agent.

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