ensation of binary mixture of vapors of immiiscible liquids on the outer surface of a horizontal tuhe of three different diameters.
Vapor-phase mass transfer was confirmed to be described by Colburn-Drew's equation and mass transfer coefficients k were correlated by dimension less equation.
Condensing heat transfer coefficients hl were well correlated by the modified Nusselt type equation with the effect of vapor flow rate to some equation with
Furthermore, it was shown that composition of condensate was related to k_v, h_t and temperature difference through condensate laver.

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After observation of vapor-liquid equilibrium of the ternary system, 2-methyl-2-butene-isoprene-aceto nitrile, the smoothed iso-vapor composition diagram was given. The ternary vapor composition could be estimated from two individual binary data, 2-methyl 2-butene-acetonitrile and isoprene-acetonitrile, ac cording to Van Laar equation withodi error.
The phase behavior and the degree of in relative volatility of isoprene to 2-methyl-2-butene, when water was added to the ternary system, were also reported.

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Thermal cracking of kerosene was carried out in a non-catalytic tubular cracker using steam as dilution gas, and the following conclusions were obtained under the conditions, cracking temperature 550-570°C, dilution ratio 1.5-5.5 g-steam/g-kerosene and residence time 0.3 sec,
1) Total gas conversion and ethylene.conversion were over respective 0.7 g-gas/g-kerosene and 0.3g ethylene/g-kerosene according to conditions, and this ethylene yield of kerosene is not less than that of naphtha.
2) Thermal cracking was assumed to proceed ac cording to 1st order reaction of liquid component except severe conditions, and the rate constant was calculated as
k=7.9 × 10⁷ exp (-32 × 10³/RT).
3) The effects of axial temperature distributions of tube wall on cracking progress were analysed numerically, and calculation results showed a fairly good agreement with experimental data.

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The reduction of cuprous oxide, in the form of flat plate, in hydrogen gas was performed in a flow system at temperatures from 215 to 340°C. It was found that the conversion-time curves had sigmoid shape, or the induction period appeared at the initial stage of the reaction. While, from the experimental studies using a microscope, it was also found that nuclei of metallic copper evolved on the solid surface at random and spreaded inward the solid with the form of hemi sphere.
Mathematical model taking account of these phenomena qualitatively explained the sigmoid shape conversion curves.

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The effect of the external surface reaction as well as the physical transfer phenomena on the apparent activation energy of solid catalyzed gas-phase reaction was theoretically investigated.
As a result, it was proved for an isothermal reaction system that the apparent activation energy (E_a) is expressed as functions of φ(ratio of internal diffusional resistance to chemical reaction resistance), N_m (ratio of internal diffusional resistance to external mass transfer resistance), δ(ratio of internal to external surface area), E_t (chemical reaction energy), E_d (internal diffusion energy) and E_f (external mass transfer energy).
Furthermore, it was numerically indicated that the extraordinary phenomena occurs in the Arrhenius-type plots, and that the consideration of the external surface area (external surface reaction) is very important according to the difference of solid properties (φ, σ) and operation conditions (N_m).

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Light intensity and reactant concentration profiles in a laminar-flow, parallel plate photochemical reactor are theoretically presented, assuming that reaction rate is proportional to the radiant energy absorbed and Beer's law is valid.
Experimental results of the photoreduction of ferric potassium oxalate solution, conducted in a thin glass duct with fluorescent illumination, are in good agreement with theoretical ones.
Optical thickness, reaction rate, diffusion rate and residence time are correlated to the conversion. At constant incident light intensity and constant mean residence time, the effect of the velocity profile on the average conversion becomes smaller when reactant concentration is higher so as to be optically thicker.

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With the horizontal cylindrical vessel agitated by 2 or 4 bladed turbine impeller, studies were made to detect a relation between power characteristics and the behaviors of flow. Results obtained were:
1) When rotational speed of impeller is large enough, liquid flows along the inner wall of cylinder.(named B state)
With decrease of impeller speed, this flow pattern changes to the state, liquid was scrubbed by the impeller.(named A state) The transitional point A to B and B to A were expressed by
A-B transition: N_FrN_Re^0.12ε^4.0=K₃ K₃=1.8: 2 bladed turbine =1.5: 4 bladed turbine
B-A transition: N_FrN_Re^0.25ε^4.0=K₄ K₄=3.9: 2 bladed turbine =1.5: 4 bladed turbine
2) Correlation between Np, N_Fr. and ε was expressed by Np/ε²=f (N_Frε^3.3), ε=0.45-0.8.

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Time-smoothed velocity and velocity fluctuation in non-baffle type agitated vessels with paddle impellers of various widths were measured by electrochemical method. The results show that the jet point of circulation flow from wider impellers is devided into two.
Besides, from analytical study of rotational velocity distribution, it was found that the relationship between rotational and radial velocity components was linear and that the transport phenomena at the wall of agitated vessel were influenced strongly by the rotational flow but slightly by the radial jet flow

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Solubility curve and tie-lines were determined for the systems acetic acid+water+aliphatic ketone (methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone) at 25°C.
The concentration of acetic acid in equilibrium layers were well correlated by Hand's plots and Hirata's plots.
The plait point was located by the method of Treybal, Weber and Daley or from extrapolation of author's correlation line.
Although the homologous ketone is one of the components of each mixture, the shapes of solubility curves and distribution curves are considerably different for these systems.
The curves for the acetic acid+water+diisobutyl ketone are resemble to curves for the acetic acid+water+ hydrocarbon systems.

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Under some conditions, the early stage of the crystallization process of gibbsite in sodium aluminate solution is accompanied by an agglomeration in addition to the growth on the crystal surface of the seed.
This paper deals with this agglomeration phenomenon experimentally and theoretically. And a critical condition of agglomeration was made clear quantitatively and a correlative equation between the agglomeration rate and crystallization conditions was obtained.

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In the absence of reversed responses, in a liquidliquid perforated plate extraction column, unsteady state dispersed phase hold-up characteristics of the top plate are approximately expressed by a first order transfer function for the change of dispersed phase inlet flow rates.
The time constants for the top plate are larger than that of the other plates, then the time constants of the column hydraulics are represented by that of the top plate.
The theoretical time constants are in good agreement with the experimental one that were obtained for water-kerosene systems.

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