A water film flowing down an inclined copper plate with flash-boards was dispersed as charged drops into a stagnant dielectric liquid phase under a direct electric field applied vertical to the film surface. The dispersion characteristics were examined experimentally for three kinds of dielectric liquids under various operating conditions.
The holdup fraction of the drops formed depends significantly on applied voltage, inclination angle of the plates and flow rate of the film phase. The electrical dispersion from the film phase and the electrical coalescence between drop and film phases contribute to effective agitation between the liquids adjacent to the interface, and rising and falling motion of the drops provides satisfactory mixing in the bulk of the continuous phase.

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The resilience in both static and dynamic aspects was investigated for three types of heat-integrated double-column distilling processes. First, the static performance of each distilling process was evaluated by the amount of energy consumption and Type A was found to be more energy-efficient than the other two processes. Second, a decoupling control system was designed for each distilling process in which significant delays in state and control variables are involved, and control responses were compared to confirm that Type B is superior to the other two in dynamic performance. Finally, the resilience of the decoupling control system for distilling processes under consideration was studied in view of both steady-state economics and dynamic-state operability by introducing static and dynamic indices of resilience.

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A mathematical model of heat and mass transfer on the rotating evaporator surface in a centrifugal molecular still is developed. The solutions of surface temperature profile, rate of evaporation and liquid film thickness for liquid of Pr < 100 are obtained in the case where the temperature of liquid on the rotating evaporator surface varies with evaporation. These solutions in the limited case of constant surface temperature agree with those of Greenberg.
The dry-out position of liquid on the rotating evaporator surface can be estimated from the present model.

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An experimental apparatus was constructed to experimentally verify the numerical analysis used for determining convective heat transfer for laminar flow in a vertical pipe with variable viscosities and under cooling conditions.
Both temperature and velocity profiles are found to be readily determined by values of X⁺ (= z/(Re • Pr •D)) and viscosity ratio (μ_i/μ_w) based on the inlet and wall temperatures. The maximum velocity deviation from Poiseuille flow is observed clearly at X⁺ ≅ 0.02 for all viscosity ratios covered in this work. For smaller values of (μ_i/μ_w), the Nusselt number decreases, reaches a minimum and then increases with increasing X⁺. On the basis of numerically calculated Nusselt numbers, a more reliable semiempirical equation is proposed to predict Nusselt numbers for a highly viscous fluid.
To cool a highly viscous fluid, it is recommended to gradually cool the fluid under conditions where there is a small viscosity variation with the surface temperature of the heated section.

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Measurement of the extraction equilibrium of silver(I) from nitric acid and aqueous ammonium nitrate solutions with triisobutylphosphine sulfide (TBPS) in toluene was carried out at 303 K to examine the effects of the concentrations of nitrate and hydrogen ions and silver in the aqueous phase as well as that of the extractant. It was found that the extraction equilibrium is explained in terms of the solvation of silver(I) by TBPS with simultaneous transfer of a nitrate ion into the organic phase to form an ion-pair and that the extracted species in the organic phase is the sliver: TBPS 1:2 complex.

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Rate equations were derived for a two-step enzyme reaction which produced L-alanine from ammonium fumarate via L-aspartic acid by aspartase of immobilized Escherichia coli cells and L-aspartate β-decarboxylase of immobilized Pseudomonas dacunhae cells.
To establish an efficient system for industrial production of L-alanine, we investigated the design of adequate bioreactors on the basis of the simulation of this sequential reaction by solving the simultaneous equations derived.
As a result, L-alanine was found to be produced efficiently by use of two sequential column reactors: a conventional column reactor containing immobilized E. coli cells and a closed column reactor containing immobilized P. dacunhae cells.

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Decoupling control of nonisothermal CSTR with dead times in control variables was investigated on the basis of a linear time-varying time-delay model by which both nonlinearity and time-delay characteristics involved in the CSTR dynamics are simultaneously considered. A pair of nonlinear time-delay decouplers were theoretically derived and the feasibility of designing a decoupling control system which requires the estimation of future values of the state variables was ensured by using a predictive scheme in combination with the control system. For the purpose of improving the control performance of the decoupling control system in which incorrect design of the decouplers is caused by identification error of uncertain parameters present in the CSTR dynamics, a feedback control system with the Smith compensator was designed for incompletely decoupled CSTR and the robustness of such feedback control system to disturbance was shown by simulations.

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The electric currents flowing through the pathways existing in a bipolar packed-bed cell (BPBE cell) were calculated by use of an equivalent resistance model which was a modification of the King-Wright model for the bipolar rod cell. The bypass, Faradaic, and total currents were shown as functions of the resistance coefficient, the specific conductivity of electrolytic solution, the number of bipolar layers, and the decomposition voltage.
In the BPBE cell, graphite pellets of 4.74mm diameter and 5mm length were packed in layers which were separated by plastic nets. Methoxylation of furan was studied, where bromine was used as mediator.
The resistance coefficient for the bypass current was evaluated from experimental results and the Bruggeman equation. The resistance of the total current flowing in the open space of the insulation net was affected by the cell configuration, such as the arrangement of the insulation nets. In the reactor under discussion, the reaction resistance was negligible, and the respective currents through the pathways could be represented by the model proposed. The overall current efficiency based on the total current and the energy consumption were also evaluated. The intrinsic current efficiency based on the Faradaic current of the reaction was more than 0.9.

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The phase equilibria in the binary systems CO₂-C₂H₅OH, CO₂-H₂O and in the ternary system CO₂-C₂H₅OH-H₂O were measured at temperatures near the critical point of CO₂.
The Patel-Teja equation of state, which is known to describe well the saturated properties of pure components CO₂, C₂H₅OH and H₂O, was tried for the correlation of phase equilibria in these binary systems. However, good correlation was not obtained. The most probable reason for this is the assumption of random mixing of molecules in the equation.
To take the local molecular concentration into account, Wilson''s model was applied to improve the mixing factor in the Patel-Teja equation. This has remarkably improved correlation for the phase equilibria of the binary systems. It has also been found that the phase behavior of the ternary system can approximately be predicted, but equilibrium concentration estimations are not yet satisfactory.

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To obtain information on the hydrodynamics of gas-liquid-fine solid particles flow systems, gas holdup and pressure drop in vertical upflow and downflow tubes were measured at comparatively high fluid velocities.
The following experimental results were obtained.
1) Within the range of experimental conditions, gas holdups in vertical upflow tubes are independent of tube diameter, average size and concentration of solid particles.
2) Frictional pressure drops in vertical upflow tubes are independent of the average size of solid particles, but increase with the concentration of solid particles.
3) Gas holdup in vertical downflow tubes, except at low gas and high slurry velocities, are independent of tube diameter, average size and concentration of solid particles.
4) Frictional pressure drops in vertical downflow tubes are independent of the average size of solid particles, but increase with the concentration of solid particles.

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A simple analytical solution is proposed to predict the minimum bed length, Z_min, necessary to make two adsorption zones in bi-component fixed-bed adsorption separate from each other, by use of the so-called constant pattern concept and the linear driving force approximation. Values of Z_min obtained from the analytical solution were compared with those from numerical breakthrough curves based on a rather rigorous mass balance as well as diffusion equations. The solution was found to be accurate enough. Experiments were performed for two monohydric alcohols-activated carbon and two monocarboxylic acids-activated carbon systems, respectively. Comparison of the predicted Z_min based on the proposed equation gave larger values than the experimental values.

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The quality of fluidization of FCC particles (d_p = 60μm) was studied by using six kinds of fluidizing gases in a 0.081 m diameter column. As several investigators have described, minimum fluidization velocity was inversely proportional to gas viscosity and was almost independent of gas density. The expansion ratio of the emulsion phase was, however, dependent on gas density and increased with viscosity and density. Both measured bubble frequency and deviation of pressure fluctuations were also influenced considerably by the gas properties. The voidage of the emulsion phase was considered to be dominated by the properties of the gas flowing through the emulsion phase. Thus the apparent viscosity of the emulsion, i.e. the quality of fluidization, is influenced by those properties of gases.

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A thin porous ceramic membrane made by a method quite similar to that proposed previously²⁾ was used for gasphase separation of alcohol/water gaseous mixtures (methanol/water, ethanol/water and isopropanol/water systems) at their normal boiling points.
The results show that this kind of ceramic membrane is quite efficient for bypassing the azeotropic point in alcohol/water separation and also for further enrichment of alcohols. The separation factor observed for these systems was larger than 5.

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