Newly approximate expressions for the viscosity of non-associated liquids have been derived as follows from the simple mode where the liquid system is regarded as an uniformly concentrated dispersion of rigid molecules and the velocity of them during each collision follows to Boltzmann's statistics.
(1)
(2)
where, b_T^-3=ρ_0μ/ρ_c, α=(1/K₄R^2/3)/(ξ_cz_c^2/3). And ξ_c, z_c are Lichit-Stechert's critical mobility and critical compressibility, respectively. The values of b_T^-3 and 1/K₄R^2/3 are close to 3.0 and 3.0 (10) ^-4.
More than 300 experimental points of non-associated liquids have been compared with Eq.(1) and about 200 pints of simple liquids, Ar, Kr, Xe, Co, N₂, O₂, p-H₂, Methane, Ethane, Benzene, Cyclopentane and others also with Eq.(2). Eq.(1) produced an average deviation of smaller than 2% for the range of ρ/ρ_c≥2.8 and Eq.(2) produced 2% for the range of ρ/ρ_c≥2.3, respectively.

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Effects of cold work on corrosion rate of metals by flowing solution were studied with corrosion tests of cold drawn mild steel bars by flowing dilute hydrochlo ric acid solution and following results were obtained
i) Initial corrosion rate of mild steel in creases with increase of its reduction of area This is mainly clue to increase of heterogeneity of ferrite grain and in crease of hydrogen evolution rate at cathode with deformation of cementite by cold work
ii) The specimen surface of a heavily cold worked bar is roughened by corrosion in fine and complex manner The surface roughness of a specimen after test decreases with increase of its reduction of area
iii) Estimation method of the lifetime or the cor rosion allowance of cold drawn mild steel bar, was obtained.

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Absorption of two gases accompanied by a bimole cular reaction in the liquid phase is studied theoreti cally and experimentally Basic equations based upon the penetration theory are solved numerically by a finite difference method, and charts of reaction factors of two gases are presented for various combinations of parameters.
Simultaneous absorption of CO₂ and NH₃ into water was carried out with a liquid et column and a wetted wall column, and experimental data are analyzed by taking into account the reaction factors of both CO₂ and NH3 It is found that observed absorption rates of CO₂ are in good agreement with theoretical pre dictions.

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On the basis of employing the equivalent diameter of bubbles, the effects of the non dimensional opt rating conditions, such as R_A, W, U and ν on the conversion have been evaluated by the u, e of the mathematical model proposed previously by the authors with the aid of digital computor.
Cross flow rate of gas between bubbles and, surrounding dispersed phase has been taken as.i para meter of the model and the relations between parameter and conversion have been discussed on the basis of sensibility coefficient.

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Equations of fluid solid reaction in fixed bed reactors under isothermal conditions are exactly and analyti cally solved for concentrations of both reactant fluid and solid, and the general expressions of conversion of solid reactant, the advancing front of zone of reaction completion, the time for complete reaction through the reactor and the bed average conversionf solid are derivated.
Three previously solved cases from the literature are special cases of these solutions on conversion of solid reactant With these three cases, the charac teristic tendencies in profiles of conversion of solid reactant are considered, and further several new expressions of conversion of solid reactant, the time for complete reaction through the reactor and the bed average conversion of solid are shown.

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Turbulent mixing and its effect on a rapid irre-versible second order chemical reaction were investi-gated for a tubular flow reactor The turbulent mixing process was found to proceed in two stages, i. e., in the first mixing stage the liquid-components injected Into the reactor were roughly dispersed Into comparatively large lumps mainly by the convective-action of liquid flow, but their uniform dispersions were not expected In the second mixing stage the lumps of dispersed fluids were more diluted in con-centration, and so uniformly dispersed due to the turbulent diffusion that their distributions were con-sidered statistically homogeneous in a coarse scale through out flow field It was made clear that-large scale disturbances exerted on the flow field promoted effectively the mixing in the first stage, whereas, the mixing process in the second stage was similar to that in the field of homogeneous and isotropic turbu-lence

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A statistical analysis was applied to investigate the motion of solid particle in a horizontal drum mixer and the radial mixing was described as a Semi Markov process.
From the observed trajectory of a labelled particle in the cross section of the mixer, the circulation time distribution and the transition probabilities of particle in the radial direction were determined According to this experimental result, the radial distribution of particles decreased with the increase of the rotation speed of the drum and on the other hand, the distri bution to the direction of circulation flow Increased up to some critical speed Therefore, the dicrease of the mixing rate in higher rotation speed may at-tribute to that of the radial distribution
A digital simulation of the mixing process was presented by employing the theory of Semi-Markov process Excellent aggreement was obtained between the result of simulation and the photographic obser-bation

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According to the previous papers, the viscosity term in a liquid medium should be considered as two dif ferent terms those are the micro viscosity and the macro-viscosity The former is related to the diffusion of the solute and the latter to the flow and the agitation of the medium
Consequently, the viscosity term in the Wilke-Chang equation should be the micro viscosity of the medium instead of the macro-viscosity
The diffusion coefficients of a solute in a 1%CMC aqueous solution and in a 20%kaolinite clay slurry were estimated by means of the modified wilke-Chang equation which is presented in this paper They are nearly equal to Clough's experimental and estimated values

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In order to investigate the flow pattern in the horizontal epitaxial reactor, the stream lines of smoke and concentration profile of oxygen gas as the tracers are observed.
The following results were found, there are two symmetrical spiral flows rasing up at the center region and going down at the wall sides of the pipe, and there is no mixing or very little mixing between the stream lines
Those results are applied to improvement of the epitaxial reactor on semiconductor industry

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Conductometric method, which uses electrodes as conductivity probe, is often adopted for the measure ments of mixing of electrolyte tracer in aqueous solution.
Then, authors tried to measure precisely such a rapid mixing phenomena as turbulent mixing by con ductometric method, using small electrodes which have spatial resolvability of 0.01mm³, and electric circuits which have uniform frequency response characteristics from 0 to 3kHz, signal to noise ratio more than 50 or 70dB and excellent linearity.

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This paper deals with an unsteady state method for observing the effective diffusivities in liquid phase within particle beds of glass and soils, and also, some discussions are done as to the experimental results for porous solids such as catalytic pellets as well as the data for the particle beds Both results indicate that the effective diffusivity of KCI or NaCl in a certain porous medium can be regarded as a constant at a temperature

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