The approximate calculations of the forces at the narrowest portion of the liquid bridge between two spheres of equal site or the conical apex and the flat plate were performed. On the basis of these results, the tensile strength of the wet granular materials of spherical and irregular shapes has been considered.Consequently the semi-theoretical equation which agreed fairly well with the experimental values was obtained. This equation includes two factors which were determined experimentally. One of which has been correlated with the void fraction of the packed bed and the other with the degree of circularity of the particle. Using these factors, it becomes possible to estimate the correlations in following two cases.
(1) the tensile strength and the liquid volume at the constant void fraction
(2) the tensile strength and the void fraction at the constant liquid volume

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As an example of the equi-optimum problem which is an approach to the optimum operation problem in a N-stage discrete process, the condition of equiminimum heat transfer area in a forward multipleeffect evaporators has been investigated. The operation under the condition is an optimum operation.
Applying a conversion formula about the optimum allotment problem reported previously, the equiminimum area condition can derive the formula with respect to overall heat transfer coefficient. An index which shows the deviation from minimum area is defined and its numerical values are evaluated for a few example.

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Theoretical equations expressing the longitudinal distributions of concentration in countercurrent moving bed have been derived for the case of ion-exchange process by taking account of the back mixing of liquid, the diffusion in liquid film and the intraparticle diffusion. The effects of the dimensionless factors on the distribution of concentration have been evaluated on the basis of the equations.
Experiments of Na⁺-H⁺ ion exchange have been conducted in this work. Calculated results on the distributions of concentration have been in good agreement with the observed data. The equations proposed in this report may be applicable to the determination of the operating conditions of the ionexchange moving bed and to the design of the equipment.

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Three models for photochemical reactions caused by polychromatic light were studied: side reactions (Model I), an approximation by monochromatic light (Model II) and addition of photochemical effects caused by monochromatic light (Model III). Photoreduction of potassium trioxalate ferrate whose reaction rate was proportional to the absorption rate of radiation was used to check the validity of these models. Studying the reaction in a batch reactor for the polychromatic light composed of 365, 405 and 436 mμ, the experimental values agreed well with the calculated values based on Model I. The theoretical relationship between Model I and other models were discussed.

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Three models for photochemical reactions caused by polychromatic light were studied: side reactions (Model I), an approximation by monochromatic light (Model II) and addition of photochemical effects caused by monochromatic light (Model III). Photoreduction of potassium trioxalate ferrate whose reaction rate was proportional to the absorption rate of radiation was used to check the validity of these models. Studying the reaction in a batch reactor for the polychromatic light composed of 365, 405 and 436 mμ, the experimental values agreed well with the calculated values based on Model I. The theoretical relationship between Model I and other models were discussed.

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The mechanism of gravitational settling has been generally neglected in the theoretical treatment of filtration process of submicron aerosols, owing to their small values of settling velocity. However, for particles of a few-microns in diameter or relatively high density, it becomes predominant in comparison with diffusion mechanism in low velocity region.
For this reason, the collection efficiency of an isolated cylinder due to combined settling and interception was derived analytically using the stream function of particles, and that due to combined settling, inertia and interception was also calculated numerically as the function of settling parameter, inertial parameter, interception parameter and Reynolds number.
Experimental collection efficiencies of an isolated wire exposed to the aerosol stream, were in fairly good agreement with the above theoretical ones.

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Solubility and distribution curves were determined for the systems propionic acid+water+n-hexane and propionic acid+water+cyclohexane at 25°C.
The plait point was located by the method of Treybal, Weber and Daley and estimated by extrapolation of the following plots;
where x_ω is wt. fraction of propionic acid in hydrocarbonlayer and yω is wt. fraction of propionic acid in water layer.
The both estimated values at plait point were in almost agreement respectively for the two systems.

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To obtain the fundamental data for the process of separation of phosphoric acid by solvent extraction after the nitric acid acidulation of phosphate rock, ternary liquid-liquid equilibria of the system n-butyl acetate-benzene-water were measured at 25°C.
By using of triangular phase diagram and Othmer-Tobias plot using tie-line data of this system were presented.

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