Heat and mass transfer in unicomponent system under nonisothermal condition were analyzed by utilizing the two-sided Maxwellian in Maxwell's integral equation of transfer. The analytical solution reduces to Hertz-Knudsen's equation in such a case where an evaporation coefficient is unity and system is isothermal.
According to the result obtained, apporoximation limit to mass transfer under isothermal coudition was examined.
The analytical solutions are in good agreement with the experimental results for sublimation rate of naphthalene.

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The presented paper confirms the importance of the interfacial velosity in the interphase mass transfer.
Both an experimental and theoretical study were made of the effect of the interfacial velocity on the interphase mass transfer with a tangentially moving interface in a two-laminar layers flow. In a horizontal tube n-butanol was transferred into a water phase. Preliminary experimental results had shown that the mass transfer coefficients varied unusually with both external flows in complicated manner. Once the data is rearranged according to this theoretical result considered the interfacial velocity, it is found that the experimental results is correlated well with the water-phase Reynolds number and the dimensionless interfacial velocity, and agree well with the theoretical result. When the interfacial flow is cocurrent to the water flow, the mass transfer rate increases with an increase in the interfacial velocity. At high interfacial velocity comparing to water velocity the mass transfer rate is proportional to the square root of the interfacial velocity. When counter-current, the mass transfer rate decreases with an increase in the interfacial velocity.

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In oder to examine the possibility of separation for the complex column under the given operating conditions, a distillation system with two feeds and one side cut stream of liquid between the feed plates, in addition to the distillate and bottoms has been undertaken as an illustration. A method solving the operation problem has been proposed for which the number of plates for each section are infinite. Furthermore, the behavior of the pinch point and the definition of ‘unsupplied component’ are discussed.

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Interfacial turbulence accompanying mass-transfer across liquid-liquid interface is known to increase the mass-transfer rate to an extent. The turbulence may depend mainly on the solute concentration and liquid properties. In unsteady-state transfer the turbulence is in general most evident at the initial state of contact and then gradually attenuates with the contact time. A model is proposed to describe the effects of the turbulence on mass-transfer rate from its occur rence to complete attenuation. Turbulence is restricted on the interface and its neighbor where the rate of mass-transfer is apparently controlled. Therefore, in the model the turbulence is assumed to promote apparently the diffusivity of solute and following effective diffusion coefficient is introduced with two parameters,
D=D⁰[1+pexp(-t²/τ²)]
where p is an enhancement factor at the initial state of contact and τ the characteristic time expressing the attenuation time.
The model is applied to the three kinds of published data of mass-transfer experiments, and found to express satisfactorily the effects on the transfer rate through each run.

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Experiments were conducted on the gas holdup and the rate of oxygen absorption by aqueous sodium sulfite solution containing cupric ions as catalyst in bubble columns of 12.2 and 21.4 cm diameter with suspended glass spheres as solid particles. The effects of solid particle diameter, average solid particle concentration, gas velocity, column diameter and kinds of gas distributor on gas holdup and overall volumetric absorption coefficient were investigated. Furthermore, the values of gas-liquid contact area and mean diameter of bubbles were evaluated.

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A Burnett expansion apparatus was constructed and the pressure-volume-temperature relations of dichlorodifluoromethane vapor have been established up to 19 atm and at temperatures varying from 300° to 75°C. The second and third virial coefficients were derived from the experimental data obtained in this work. From these virial equations of state, compressibility factors of dichlorodifluoromethane vapor were also calculated.

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As it is known experimentally and theoretically that in the closed moist granular bed under the temperature gradient, the moisture gradient in the bed is relatively small compared with that of temperature, effective thermal conductivity of moist granular bed (consists of spherical glass beads, crushed marble or stainless steel particles wetted by water or ethanol) is measured by comparison method carried out in the stationary state.
Experimental data show that the values of effective thermal conductivity of moist granular bed increase with increase of moisture content and increase of average temperature of moist granular bed. When the average temperature of moist granular bed becomes higher than a certain temperature, the curve of effective thermal conductivity vs. moisture content has a maximum point. The reason for this fact is considered to be due to the cycle of evaporation-diffusion-condensation by which heat flux is increased than in only the heat conduction under a certain temperature gradient.

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