Drop formation in the dispersion from sharp edged single nozzles of one liquid into another stationary immiscible liquid or gas was studied as a function of the physical properties and flow conditions of the system.
Systems and nozzles employed are listed in Tables 1 and 2, respectively. The variables govern- ing drop formation are assumed to be: density of both dispersed and continuous phases; viscosity of both phases; interfacial tension; nozzle shape and diameter; velocity of the dispersed phase through the nozzle.
For the following 4 cases, experimental data are correlated by the experimental Equations (21),
(22), (23) and (24), respectively.
(i) for μc≤12cp and dF≥dN; Eq. (21)
(ii) for μc≤12cp and dF<dN; Eq. (22)
(iii) for μc>12cp and dF≥dN; Eq. (23)
(iv) for μc>12cp and dF<dN; Eq. (24)

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It is widely known that the enthalpy-concentration diagram is useful for the calculation of heat balances in physical and chemical processes of binary systems. A method of constructing such a diagram was described by McCabe⁶⁾ and Hougen, Watson and Ragatz.²⁾
The author has constructed a chart for NaCl-H₂Osystem, employing liquid water and puresalt at 0°and under 1 atm. (Figs.1 and 3). As theheat capacity of this solution had scarcely been measured in the range of above 60°C, its enthalpy was calculated from the actívities of NaC1 in the solution, evaluating vapor pressures and elevations of boiling point by equations (6), (7), (9) and (10). Other adequate data are also available.

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The author reported the method of designing a general multistage reactor in the previous paper. In industrial practices, however, we are often encountered with many cases, in which reaction rate increases progressively with the rise in the temperature and the maximum rate can be obtained at the highest temperature attainable.
The author has developed, in this paper, a new theory which is considerably useful when we design a multistage reactor in like cases mentioned above.
If some multistage reactor, whose temperature is limited by upper limit for some reasons, contends to be ideal, following conditions must be satisfied.
(1) In every partial reactor, outlet temperature has to be always T_max.
(2) In every partial reactor except the last,
integration: over i-th reactor
m: heat of reaction divided by heat capacity
The author applied this theory to water gas shift reaction where T_max=400°C, with a great success.

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Longitudinal mixing in continuous flow reactors with multi-stage impellers (see Fig. 2) was studies on·the basis of the residence time curve.
In such a vessel, the liquid flow is assumed to be a combined flow of piston flow and perfect mixing. Defining the fraction of piston flow (φ), the conversion (z) was related with it as in Eqs. (2), (3) and (4).
Values of the fraction (φ) were studied by means of tracing the residence time curves, and they were correlated as presented in Eq. (8) and Fig.7 for all vessels as shown in Fig.2.
The correlation between the fraction of piston flow (φ) and the mean mixing diffusivity (E) is shown in Fig.10. E was correlated as in Eq. (14) and Fig.11.
Fig.12 indicates that good agreement was attained between the values Zcalc., obtained from the above equations, and zobs., observed in our experiments on the hydrolysis reaction of acetic anhydride.

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Pseudoplastic fluids are excellent stuff for study, because they are a solution consisting mainly of high molecular compounds. But heat transfer coefficients of pseudoplastic fluids have scarcely been investigated except by Chu and others whose data on water solution of PVA are limited mostly to turbulent flow.
The author conducted experiments on heat transfer coefficients in laminar flow, using starch paste, with a view to theoretically solving heeat transfer in laminar flow of pseudoplastic fluids.
n, η_psu and η_psu* of starch paste were obtained from the results shown in Figure 4, and heat conductivity and specific heat from the results in Figures 1 and 2.
For laminar flow, the following equation was obtained with the aid of data on heating and co- oling of starch past
By rearranging Chu and others' data on water solution of CMC, PVA, and SPM, and the autho's data, an equation for laminar flow was obtained as:
or
Further, when Re_psu was from 2, 000 up to 8, 000, the results were as shown in Figure 8.

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The authors proposed fundamental correlations among some variables having influences upon the design and operation of closed-circuit grinding¹⁾, and then a new index for expressing the performance of a classifier as the ratio of a specific surface of tailing to that which would be obtained if the ideal separation should occur.²⁾
In this article, it is reported that the index a obtained from the operating data on several mechanical classifiers employed in Japanese cement plants for treating raw material is found to be about 3-5, which differs considerably from 1 obtained in the case of an ideal separation. The index varies with the change in the specific surface of feed powder, the parting size and the circulating load, as shown in Eq. (12). The parting size x_c, which has already been defined by Tanaka, ²⁾ is correlated with the dimensions of all parts inside the classifier and rotating speed of shaft as shown in Eq. (10). The maximum size of particles in fine x_m, is theoretically treated and then observed by means of a microscope. The relation between parting size x_c and the maximum size x_m is illustrated in Fig.5.

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Total reflux distillation was studied as a method of batch distillation. Fig.1 is an explanation diagram of total reflux distillation. The distillation system consists of a column and a total condenser as usual: in addition, it has a large-sized, volume-adjustable overflow vessel which is set up in reflux-return passage between the outlet of total condenser and the column top.
In the course of total reflux distillation method, a large volume of liquid holdup of constant composition in the overflow vessel is taken out as distillate, after the distillation system has attained to the equilibrium state, due to the constant reflux ratio of total reflux.
The total reflux distillation is operated at the reflux ratio of the total reflux; therefore, unlike in ordinary distillation, it is not necessary in this case to select reflux ratio for operating variable. But, in order to obtain distllate of desired composition, volume of the overflow vessel should be controlled so that the liquid holdup will be in a definite condition.
The fundamental equations for total reflux distillation are obtained from material balance in reference to the distillation system: Eqs.1 & 8 are general equations for a plate tower and a packed colum with binary mixtures, respectively. Eqs.5 and 12 are special cases in which vapor holdup in the column and vapor-liquid in vapor line and total condenser are negligible, and liquid holdups of any plate are equal. Eqs.7 and 14 are applicable to mixtures which obey Raoult's law.
Fig.6 (right) shows the experimental results of total reflux distillation in a packed column, Fig.6 (left) the results calculated by means of Eq.12, and Fig.7 over-all comparison. According to these figures, the experimental and calculated results approximately agree with each other.

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Crushing was accomplished by dropping a steel ball on a plunger resting on cubic or powdery samples (Hakun stoneware) in a steel mortar, and it was sometimes accomplished by driving a ball mill at normal speed. The experimental results were as follows:
The relation between pass-through of the crushed products and no. of blows is shown in Figs. 2 & 3. In these figures, pass-through increment D_z-D_z-1 shows Max. value when Z=Z_m, and it falls in value, down nearly to zero, when. From these experimental results, the authors have assumed that the relation between net work input to crushing and no. of blows is given by Eqs (3) & (4).
The authors have round close similarity between these equations and the corresponding experimental results. The relation between residue or surface increment and the net work input to crushing is represented by Eqs.(5) & (6). Eqs (3) & (4) are applicable to not only cubic samples but also powdery samples (of same size) crushed in a mortar or in a ball mill driven at normal speed. In Fig.9, the authors show how to select the most effective no. of blows Z_opt.
By studying Figs.2, 4 etc., the authors have found that the curve is concave upward for smaller values of no. of blows Z, and convex upward for larger values, but nearly linear for medium values. When the work input to crushing in the Rittinger's, Kick's and Tanaka's law is assumed to be proportional to no. of blows, Eqs.(4) & (6) correspond to the Kick's law for the 1st stage of crushing, to the Rittinger's law for the 2nd stage and to the Tanaka's law for the 3rd stage.

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