The design procedure and the operation performance of a new continuous photoreactor for laser-induced tritium isotope separation were studied experimentally. The investigation of the design procedure consists of the following three steps: (1) extraction of the parameters for dissociation characteristics from focused-beam batch irradiation experiments: (2) model modification in the vicinity of the critical fluence and (3) prediction of reactor performance as a function of externally controllable variables such as the pulse energy and the gas flow rate.
The results of continuous reactor experiments under realistic operating conditions were found to agree with the predicted performance and a design method was established.

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Middle molecules, which are contained in the blood of chronic renal failure patients, can be detected by using high-speed liquid chromatography. Analysis of blood or dialysate with HSLC is completed within 35 minutes. Application of a two-pool model for the body water of the patients clearly indicates that MM has a tendency to be removed mainly from extracellular space.

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The movement of solid particles through the partition plate was investigated in a multistage bubble column with continuous flow of liquid containing suspended solid particles. A mathematical model for use in predicting the solid concentration difference through the partition plate was derived on the basis of theoretical consideration of factors controlling the flow of liquid with suspended solid particles through the plate.
Using experimentally observed data of solid concentration distribution in gas and slurry cocurrent upflow multistage bubble columns of 10 and 20cm in diameter, model parameters governing the solid concentration difference through the partition plate were correlated with the operating conditions. The transition of solid concentration profile within the column from a stepwise distribution at zero and/or low liquid flow rate, to a sawtoothed one at high liquid flow rate was interpreted by applying the model. From observed values of the gas holdup, the slip velocity of gas against liquid in the multistage bubble column was also correlated with the operating conditions.

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Characteristic behavior of cubic equations of state was analyzed through the utilization of a generalized expression involving two adjustable parameters u and w. A possible approach for developing a new equation or modifying an existing equation for a specific purpose was presented. For illustration, two three-parameter equations (one for general purpose (3PR) and the other for representing specifically saturated liquid volumes (3VL)) were proposed and evaluated.

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Measurements of diffusivity of aluminium potassium sulphate dissolved in water near the surface of crystal of the same substance either growing or dissolving in the solution at rest were made under unsteady state condition. The diffusivity was found to increase remarkably from the lowest value at saturated condition with increasing degree of super- or under-saturation. Correlations between diffusivity and concentration were proposed.
Experimental correlations were applied for the flow system to estimate the growth and dissolution rates of the crystal. The estimated results are shown to be closely related to the experimental results reported elsewhere by the authors.

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Apparatus made of copper and acrylic pipes of 14 mm, 19 mm and 25 mm i.d. were constructed to study the fundamental characteristics of heat transfer from the wall to water suspensions of glass beads (d=0.06 to 1.0mm) or ion exchange resin (d= 0.8 mm) flowing through horizontal pipes. The operating range of Reynolds numbers and volume fraction of solid is from 3000 to 50, 000 and from 0 to 0.1, respectively.
In the case of particle sizes larger than 0.35 mm in diameter, the heat transfer coefficient is always larger than that of a simple water flow and is not strongly affected by particle size, pipe diameter or volume fraction of the solid in the asymmetric suspension flow. In the case of particle sizes smaller than 0.15 mm in diameter, on the other hand, heat transfer reduction is found to occur in the range of Reynolds numbers from 6000 to 15, 000.
The temperature profiles of fluids in the horizontal radial direction are symmetric with respect to the pipe axis even at low Reynolds numbers. In the vertical radial direction perpendicular to the pipe axis, the temperature profiles of fluids are asymmetric with respect to the pipe axis.

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Diffusivity measurements between two inorganic solids, zinc oxide and zinc illuminate, in the absence of reaction was undertaken with particle size, compaction pressure, diffusion temperature and diffusion time as variables. The present work was mainly concerned with the experimental techniques of measurement and the establishment of the concentration profile for diffusion of zinc oxide into the zinc aluminate through which fundamental as well as concentration and temperature diffusivities were determined. Activation energies required for fundamental as well as concentration and temperature diffusion were calculated and reported. Generalized correlations were also established.

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Diffusion and reaction between two inorganic solids, zinc oxide and aluminium oxide, was undertaken in single cylindrical pellets with their end faces in contact with each other. Assuming a second-order irreversible reaction between the reactants, the second-order rate constants were determined as functions of particle size, compaction pressure and temperature. The activation energies required for reaction alone were computed. Generalized correlations for the second-order rate constant as a function of initial porosity of the compact were also established.

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Interrelations among the non-dimensional mixing time, the power number and the discharge flow rate number for baffled mixing vessels are experimentally investigated for paddles and turbines of various dimensions. The correlation equations with the geometrical dimensions of the impellers are presented for the mixing time, the power number and the discharge flow rate number, respectively. The power number can be directly correlated to the discharge flow rate number to the 1.34 power. The mixing time is proportional to the time required to circulate the discharged liquid once, as proposed by van de Vusse in 1955. The number of times of circulation of the liquid to reach the mixing time is correlated with the geometrical dimensions of the impellers. The relations of the nondimensional mixing time with the power number or with the discharge flow rate number are presented. The impeller with larger diameter, larger breadth and greater number of blades is recommendable within the experimental range for turbulent mixing from the point of view of energy saving.

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A new mixing rule based on a statistical mechanical perturbation theory is proposed. It gives similar results to the van der Waals one-fluid model for mixtures of equisized molecules. A generalized equation of state utilizing the new mixing rule is applied to the calculation of high-pressure vapor-liquid equilibria for nonpolar asymmetric mixtures.
Comparisons are made with experimental data for binary systems containing hydrogen. The agreement of calculated and experimental high pressure vapor-liquid equilibria is rather good.

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To develop a widely applicable method for predicting high-pressure vapor-liquid equilibria by the equation of state, a mixing rule is proposed in which mixture energy parameter "a" of the Soave-Redlich-Kwong, Peng-Robinson, and Martin cubic equations of state is expressed by using the ASOG group contribution method. The group pair parameters are then determined for 14 group pairs constituted by six groups, i.e. CH₄, CH₃, CH₂, N₂, H₂, and CO₂ groups. By using the group pair parameters determined, high-pressure vapor-liquid equilibria are predicted with good accuracy for binary and ternary systems constituted by /i-paraffins, nitrogen, hydrogen, and carbon dioxide in the temperature range of 100-450 K.

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To produce L-alanine efficiently with immobilized microbial cells, the production system from ammonium fumarate by two-step enzyme reaction using aspartase activity of Escherichia coli cells and L-aspartate β-decarboxylase activity of Pseudomonas dacunhae cells in a single reactor was examined. It was found that the reaction should be started at pH around 8 and that the use of a mixture of immobilized E. coli cells and immobilized P. dacunhae cells was superior to that of co-immobilized E. coli-P. dacunhae cells.

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A model is presented which describes the transient change in the surface area of silica-alumina catalysts at temperatures in the range of 751-1136 K and steam partial pressures in the range of 11.1-709.1 kPa. Silica-alumina catalysts comprise very fine spherical ultimate particles of about 5 nm in diameter, which are in contact with one another. At the point of contact of two such particles, solid material transfers from the convex surface of the particles and forms a neck with a small negative curvature. This kind of mass transfer enhances the coalescence of the two particles, and results in a decrease in the surface area of the catalysts. Rate equations for coalescence of the ultimate particles were derived under two mass transfer mechanisms: vapor transfer and surface diffusion mechanisms. The process of coalescence was well formulated by a population balance model, and the overall rate of decrease of surface area was expressed by an equation consisting of the sum of the sixth and eighth powers of the surface area. Experimental data including those of other investigators were well correlated by the proposed equation.

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