The Barker-Henderson perturbation theory utilizing a proposed empirical second-order term was applied to the calculation of P-V-T relations for polar and non-polar substances using a modified three-parameter 18-6 potential function.
The potential parameters were successfully correlated with the critical constants, acentric factor and the Stiel polarity factor for polar substances.

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Mutual diffusion coefficients in the molten lead-bismuth system were measured over the whole concentration range at temperatures from 443 to 1068 K using the capillary-reservoir method. Care was taken to avoid turbulence or disturbances liable to occur in the liquid metal system at high temperatures, and also to eliminate the oxide layer or other impurities at the interface. High reliability in the determined diffusion coefficients was realized by confirming the occurrence of molecular diffusion from the observed concentration profiles. The extrapolated diffusion coefficients at infinite dilution of lead or bismuth could well be correlated by Arrhenius-type expressions. The concentration dependency of the ideal diffusion coefficients was found to be nearly linear.

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A new apparatus has been designed and constructed in order to obtain reliable high-pressure vapor-liquid equilibrium data for binary systems. The vapor-liquid equilibrium phase compositions of the ethylene-propylene system were measured at 283.15 K, 298.15 K, 323.15 K and 348.15 K under pressures ranging from the vapor pressure of propylene (0.78-3.38 MPa) to the critical pressure of the mixture (5.00-5.57 MPa).
Simple consistency tests were applied to both vapor and liquid compositions. Their results show the reliability of the experimental data obtained in this work.
Three equations of state are used to predict the vapor-liquid equilibrium relationships of this system. Calculated values are compared with the data obtained in the present measurements. The calculated results agree well with the experimental results except near the critical region.

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Fully developed turbulent mass transfer in an isosceles triangular duct with a narrow apex angle was analyzed using the P-function proposed by Jayatilleke. Predicted results were compared with the experimental results of local and averaged mass transfer measurements by means of the electrochemical method. Although the predicted distributions of local mass transfer coefficient were similar to the experimental results, present analysis fialed to predict quantitatively the averaged mass transfer coefficient in an isosceles triangular duct. The disagreement between the prediction and experimental results was attributed to the change of turbulence structure in a turbulent triangular duct flow. The decrease of turbulent intensity and the increase of large eddy scale near the wall were detected by the electrochemical technique.

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The equilibrium relationships of the processes concerned with the extraction of Cu (II) by benzoylacetone in benzene were elucidated by spectrophotometric methods at 25°C and ionic strength = 0.1 mol/dm³. The molar extinction coefficients of the species which participate in the extraction processes were determined.

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Intraparticle distribution of adsorbate amount in cyclic adsorption and desorption is simulated by two methods: rigorous numerical solution of the particle-phase diffusion equation and the linear driving force (LDF) approximation. It becomes clear that the conventional value of 15 D_s/R² as the intraparticle mass transfer coefficient, k_sa_v, in the LDF method is not advisable for the simulation of transient adsorption and desorption. A mass transfer coefficient defined by including the cycle time is thus proposed. In this new conception, k_sa_v increases with decreasing cycle time and approaches π²D_s/R² with increasing cycle time. Simulations of cyclic mode by the LDF method using this new k_sa_v agree well in the steady state with that obtained by numerical solution of the diffusion equation. In unsteady-state operation, however, the two simulations do not coincide with each other because of overestimation of driving force for adsorption and underestimation for desorption in the LDF method.

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A diffusion equation for gas permeation through microporous media in the Knudsen regime was obtained theoretically, considering the potential energy between a gas molecule and the solid surface of pores. The equation as a function of temperature contains four parameters, all of which have physical meanings. The most significant of these parameters is the effective potential energy ε^*, by which the gas diffusion equation as a function of temperature is characterized. Permeabilities of He, H₂, CO, N₂, O₂, Ar, and CO₂ through a microporous Vycor glass membrane were measured in the temperature range from 300 K to 950 K. The validity of the diffusion equation obtained was verified experimentally and was shown to express well the previous data.
For helium in particular, diffusion is almost gas-phase flow, with no adsorbed flow except at very low temperature. However, the diffusion is affected by the interaction energy between the gas molecules and the solid surface in the pores.

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Removal of SO₂ gas from simulated flue gases was carried out, using copper oxide adsorbent. The copper oxide absorbent is made by impregnation of γ-alumina tablet in a solution of copper (II) nitrate, followed by oxidation.
SO₂ breakthrough curves were obtained by changing temperature and initial concentration in a tubular packed bed reactor. The kinetic parameters were determined by fitting breakthrough curves to the theoretical kinetic model, and the rate equation was obtained.
The saturation capacities were calculated by the numerical integration of breakthrough curves, and the equation representing breakthrough curves was obtained. By means of this equation, the influence of space time on breakthrough curves was estimated.

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The rate of "NO" reduction by carbon monoxide over calcined limestone was measured over a temperature range (588-922°C) by use of a fixed bed flow reactor. The calcined limestone was found to have a high catalytic activity for "NO" reduction by carbon monoxide and the obtained rate exceeds the rate of catalytic as well as noncatalytic NO reduction by char. A significant effect of calcined lime on NO reduction by carbon monoxide within a calciner and a fluidized bed coal combustor is suggested.

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A new procedure has been proposed to investigate the effect of irradiation geometry and extract unbiased data from focused beam experiments in laser-induced photolysis and isotope separation. The model proposed here is shown to be advantageous over previous models experimentally and theoretically. The accuracy of this model was verified by comparing the parallel beam results and deconvoluted focused beam results using photolysis of CF₃C1 with O₂ added.
As a second step, the effectiveness of this method was tested for a binary system (CTF₃/CHF₃). By comparing the results with lenses of different focal length, the effect of focusing on selectivity was mathematically well described for two extreme cases: (1) tight focusing sufficient to produce cores with complete dissociation by one pulse near the focal spot for CTF₃ and CHF₃, and (2) mild focusing without such cores. The advantage of performing the experiments with tightly-focused beam geometry before deconvolution experiments was also shown.

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