These experimental studies were carried out to make clear the effects of variable factors, such as gas velocity, liquid velocity, column diameter, column length, hole diameter, number of holes and the properties of the liquid, on the gas holdup and the average velocity of gas bubbles in gasbubble columns.
The apparatus used in the experiments is shown in Fig. 1 and 2. The gas holdup was calculated from experimental values of hydrostatic pressure and from Eq.(6).
The results obtained are summerized as follows:
(1) On increasing the gas velocity, flow regions became divided roughly into three regions:(a) a region of separated gas bubble and foam flow, where (1-ψ) increased linearly, (b) a transition region, where small bubbles coalesced to produce large bubbles and the rate of increase of (1-ψ) decreased gradually and (c) a turbulent region, where (1-ψ) approached a constant value.
(2) From the values of holdup at each height of the column, the column was roughly devided into two sections a section of the foam layer and dead space, l, and another section in which gas and liquid were uniformly distributed, l₀. By equating this relationship, Eq.(10) for the average gas holdup was derived.
For air-water system (ψ₀-ψ′) l′ was correlated as shown in Fig. 7, from which experimental equations, Eqs.(11) and (12) were obtained.
As shown in Fig. 8-12, in the separated bubble flow region the gas holdup, (1-ψ₀), was a function of gas velocity, liquid velocity, and hold diameter and independent of the column diameter, number of holes, and the arrangement of the holes. In the turbulent region, however, (1-ψ₀) was chiefly dependent on the gas velocity and liquid velocity, and independent of others.
(3) For the average velocity of bubbles Eqs.(15) and (18) were derived, respectively.
The average velocity of bubbles rising through a cross-section in a column l0 was correlated as shown in Figs. 13-15, from which it was ascertained that Eq.(17) held good for the experimental results ranging from parallel flow to counter flow of gas-liquid mixtures. Furthermore, Eq.(19) was obtained from Eqs.(18), (10), (15) and (17).

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The main objective of this paper is to obtain the correlation of kinetic viscosity which is a more fundamental and convenient property for practical application than viscosity.
The comparative correlation at equal reduced temperatures as standard was applied to a homologous series of organic compounds. n-Hexane was used as the reference substance.
The correlated lines for each homologous series showed good linearity for a wide range of temperature, and these lines, seemed to converge on one point.
Constants in linear equations corresponding to the obtained correlation lines have been determined.
By these constants, the estimation of kinetic viscosity is possible at any desired temperature.
More simple correlation is obtained with the Andrade method but it has less precision. Furthermore, the general correlation method suggested by Prof. Sato is inapplicable at least for viscosity calculation.
Considering the strong dependence of viscosity on the structure of a substance, this is a reasonable conclusion.
Hence, it seemed better as shown above to apply the correlation method according to each group of substances of similar structure.

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In the fluidized gasification process for the preparation of active carbons from organic carbonaceous materials and their carbonized products, the effective procedure of pretreating their granular particles with Cl₂ gas in a vertical tube, was introduced. The results indicated that both the yield and the quality of cyclone dusts were improved, from which it has been able to obtain uniformity in their activity at a minimum loss of Cl₂ gas.
1) For carbonized materials like charcoal, the primary activated products, with or without sifting and surface-grinding procedure, are treated with Cl₂ gas according to their adsorptive ability, and then the secondary activation is followed.
2) For such organic carbonaceous materials as lignite and the residual lignin in wood-sugar manufacturing, etc., lignin is chlorinated in the presence of 10-20% moisture. Thus the reactivity is increased and the activating reaction is promoted.
3) The fluidized gasification furnace with a combution chamber was outlined and the effects of pretreatment with Cl2 gas on the activation were also described.

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The Experiments both in absorption of NH₃-air gases by water and in desorption of carbonated water by air were carried out by means of a 15cm diam. perforated plate column without the downcomer. In the former system the major resistence to mass transfer is in the gas phase: in the latter, the liquid phase resistence to mass transfer is controlling. It was observed how the plate efficiencies and the fluidized states on the tray varied with the operating conditions. From the results of the experiments the following conclusions were obtained.
(1) The fluidized states on the perforated plate without the downcomer are too complicated to predict them from the operating conditions. Especially when the tray has smaller free area and larger hole diameter, the hysteresis phenomena are observed.
(2) As indicated in Fig. 2 (a) and (b), the plots of N_G vs. G_M show complicated curves but are very similar to those of the gas residence time T_G vs. G_M. The shapes of these curves vary little in the 18% free area trays but vary very much in the 9% free area trays with the hole diameter.
(3) The changes of N_L with liquid rate are not so complicated as those of N_G with gas rate. As shown in Fig. 3 (a) and (b), N_L decreases at first with increasing liquid rate, but varies little after the liquid rate becomes more than about 200kg·Emole/m²·Ehr. The plots of N_L vs. L_M are also similar to these of the liquid residence time T_L vs. L_M. In the 9% free area trays the relationship between N_L and the operating conditions are correlated approximately as follows: N_L=120d^-0.22L_M^-0.88Zƒ(15)
But in the 18% free area trays the equation of N_L could not be found because the relation between N_L and d was obscure.

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