The Wilson equation is useful for calculating vapor-liquid equilibrium relationships. It represents a binary system with only two parameters. However, it is not easy to estimate the two parameters. Because the least-square objective function is nonlinear with respect to the parameters, there are several sets of parameters which satisfy the local minimum of the objective function. In other words, this objective function is multimodal.
We show that the multimodality is not due to the number of data or the magnitude of the variance of data, and then propose a useful procedure for finding the significant Wilson parameters in many sets of solution.

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Atomized flame stability of the high pressure-air atomizing burner has so far been dealt with by empirical techniques because of the complexity of atomized flame stability compared with gas flame stability. In this work atomized flame stability, especially the atomized open-flame stability limit blow-off, using a high pressure-air atomizing burner, was first investigated. The empirical design equations of an oil burner were obtained by Maezawa's theory of momentum. These new design equations may also be used as correlating equations of atomized flame stability limits.

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Light intensity profile and average light intensity in an annular photochemical reactor were investigated theoretically and experimentally. Although radiation from a jacketed high pressure mercury lamp in the whole range of solid angle was relatively close to that from a diffuse line source, the specular line source approximation was valid in a particular range of solid angle subtended by the reactor volume. The light intensity profile measured by CdS probes, the observed photoreduction rate of potassium ferrioxalate and the efficiency of light utilization in this particular lamp-reactor system were explained well by the specular light source model.

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A two-dimensional model relating to the behavior of a single particle was devised in the course of an investigation into the dynamic motion of a moving solids bed. The relationship between stress and strain rate of the system and the solids-velocity distribution, derived from the model, were confirmed by measurement of the radial distributions of both the radial normal stress and the vertical velocity of particles flowing under the influence of gravity through a vertical circular tube. As a result, these approximate conclusion were reached.
1) Increasing or decreasing of normal stresses in the direction of radial distance is proportional to the square of the velocity gradient, -∂u_z/∂(r/R), where r and R are radial distance and half span of bed diameter, respectively, and uz is the velocity in vertical direction. For example, concerning the mean normal stress, σm,
2δm=(constant)[-∂u_z/∂(r/R)]²+(function of vertical distance)
2) The solids-velocity distribution is
u_c-u_z=(constant)[-∂u_z/∂(r/R)]
where uc is the constant velocity in the central core of the moving bed.

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To elucidate the flow mechanism in an unbaffled agitated vessel, detailed measurements of threedimensional velocities and static pressures are made and the results are compared with each other, using three kinds of impellers of different size or different number of blades. It is found that axial gradient of centrifugal force is similar except in and near the impellers, while flow pattern of secondary circulation is similar in the region of return flow to the impeller. Secondary flow gains vorticity in the region closest to the impeller on stream line, and the vorticity diffuses rapidly with distance from the impeller, due to viscosity. These results can be interpreted qualitatively by consideration of the vorticity equation in the circumferential direction referring to time mean velocity. In contrast to this, radial distribution of circumferential velocity does not show simple similality. It is inferred that this non-similarity is owing to the difference of transfer mechanism of stress moment from impeller to vessel wall. Other interesting results are:
1) Circumferential velocity distributions in the region near the wall are almost the same if radii of impellers are the same.
2) Signs of static pressure gradients along axial direction in the region near the wall always change from negative to positive.
3) In an open vessel, flow pattern in the upper half of the vessel is not symmetrical with that in the other half of the vessel.

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Solid-liquid phase diagrams of water-quinol-gas (SO₂, H₂S and CO₂) ternary system were constructed. Using these diagrams, some quantitative explanations for gas absorption and regeneration by clathration are given.

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