A new method modifying a cloud point technique is presented for the determination of ternary liquidliquid equilibria. Tie lines are obtained by means of the measurement of total pressure at the cloud points. Ternary liquid-liquid equilibrium data for the system benzene-water-ammonia at 20°C and 0°C are determined by means of this method.

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The screw extrusions of Newtonian fluids and power-law model fluids of various rheological power n are studied, assuming the flow is taken as steady, imcompressible and isothermal. The single-screw extruder designed constant screw pitch and constant groove depth is used.
The non-dimensional momentum equation on the extrusion is analysed by a finite difference method by means of an electronic computer. In showing the flow patterns of the fluids in the channel, the velocity is divided into two components: one of these acts on directly down the channel, and the other acts at right angles to it. The fomer component which is called drag velocity is related to the discharge rate from the extruder, and the latter component which is called transverse flow is related to neading and heattransfer in the channel.
The mass flow rate is studied with the experiments and the numerical analysis under various operating conditions, and the screw characteristics of the extruder are also given in the non-dimensional form.

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Equilibria and kinetics of dissolution of slightly soluble sulfates (Ca, Sr, Ba and Pb) suspended in water by cation exchange resin in H⁺ form (Dowex50W) were studied in stirred vessel at 30°
Since the solubility of sulfate and total acid concentration in solution (H⁺+HSO) ₄^- vary with the hydrogen ion produced by the cation exchange, the relation between hydrogen ion concentration of liquid C_H and the ratio of weight of resin added to initial amounts of water and the effect of C_H on exchange ratio in the resin-phase were determined at equilibriumrespectively and the results were shown in the diagram.
The rate of dissolution was determined by the variation of C_H with time in the presence of large excess of fine sulfate particles, so that the mass transfer resistance at the liquid-salt interface is negligible. The rate equation was represented in terms of the function of C_H on the basis of the equilibrium. It was found that the dissolution rate curve follows the rate equation and the operating conditions correlate to mass transfer coefficient for Ca and Sr except Ba and Pb sulfate which have extremely large driving force perhaps by the formation of supersaturation.

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Effect of temperature on the rate of copolymerization of styrene and acrylonitrile in dimethylformamide solution was examined at the temperature range between 55 and 80°C.
Each parameter in the rate equation proposed in a previous paper was determined at each temperature to obtain the apparent activation energy of each parameter.
Consequently, it was found that the apparent activation energies of the over-all rate constant and f (x) were about 21 Kcal/mol and -39 Kcal/mol respectively, and that these values were not affected by monomer composition x. Furthermore it was shown that the effect of temperature on the reactivity ratio and φx was negligible.

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The bulk copolymerization of styrene and acrylonitrile at 70°C, with azobisisobutyronitrile as initiator, was studied over the complete course of the reaction. The monomer concentrations for each reaction time were measured by gaschromatography and the weightaverage degree of polymerization of azeotropic copolymer and styrene homopolymer was determined by viscometry.
Consequently, it was found from the copolymer composition diagram that copolymer reactivity ratio was not always constant over the complete course of polymerization, and that this was correlated with moles of polymerized monomers per unit mass. A factor γ was introduced in the rate equations to represent quantitatively “gel effect” observed in final stage of polymerization. This factor was also correlated with moles of polymerized monomers per unit mass.
The experimental results, that is, the conversion and the weight-average degree of polymerization, agreed with the results calculated by the rate equations taking account of “gel effect”.

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The suspension copolymerization of styrene and acrylonitrile at 70°C, with azobisisobutyronitrile as initiator, was studied. The effects of suspension agent concentration, stirring rate and the volume ratio of monomer to aqueous phase on the rate of polymerization were examined.
It was shown that the rate of copolymerization was not affected by suspension agent concentration and stirring rate, but by the volume ratio of two phases. The experimental results of suspension homopolymerization of styrene agreed with the results calculated by the rate equation obtained from bulk homopolymerization of styrene. It was suggested from these fact that the effect of volume ratio of two phases on the rate of copolymerization was attributed to the solubility of acrylonitrile monomer in aqueous phase. Ternary liquid equilibrium of styrene, acrylonitrile and water was measured at 70°C.
All experimental results of suspension copolymerization were well explained by using the equilibrium relation and the rate equation of bulk copolymerization.

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The kinetic studies of the vapor phase photochlorination of chloroform were carried out in a tubular, laminar flow reactor from 23°C to 100°C, with due consideration of the effect of radial variation in light intensity and concentration gradients. A kinetic model based upon the following discussions was found to fit the data: a pattern for the distribution of light intensity was assumed diffuse, and the recombination of trichloromethyl radicals was taken into account as a termination step whose rate constant was proposed as 1.0×10¹³cm³/mol·sec. It was also found that the long chain approximation would not be possible under the experimental conditions studied.

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