In the study of pore distributions by gas adsorption methods, first it is necessary to measure the isotherms of nitrogen, water vapor etc.
Whenever the isotherms are completed, both complex equipment and tedious experimental operations are required. On the other hand, equilibrium, moisture contents are measured easily by the so-called desiccator method. The simplicity was noted, and discussed as to whether moisture content curves instead of gas adsorption methods can be used or not for pore distribution analysis.
The results are as follows:
1) By using t-curves of Eq. (1) to (3), it was indicated that pore distributions could be obtained from moisture content curves as same as by the water vapor adsorption method.
2) As an application of pore distributions, approximated values of moisture contents can be estimated by Eq. (8), when cumulative pore volumes are known.

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The effects of the impeller type mixer on the mixing performances of wet powders have been investigated. The types of impeller tested in this experiment were the double helical ribbon, intermittent helical blade, single inclined paddle and multistage paddles. Both the transitional torque and the torque at the steady state after the addition of water were measured as indices of the effectiveness of agitation and of the mixing time.
The degree of mixing and the mixing time were markedly influenced by the paddle angle and the distance between the two paddles. Using the two-stage paddles was more effective for the mixing of wet powders than using the other types of impellers. The optimum-angle of the upper and the lower paddle were 60° and 120°, respectively, and the optimum distance between the two paddles was influenced by the combination of the paddles. These results were confirmed by the mixing curves based on the sampling method.

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In this study, experiments on the compression by tapping were performed by using several kinds of cements. The correlation coefficients R from N/C (N: tapping number, C: degree of volume reduction) and N in Kawakita's formula relating to compression, were investigated in relation to the tapping constants, when N was in a smaller range and when N was in a large one. Next, the static bulk density ρ_bs and the dynamic bulk density ρ_bd were measured and correlated to the physical properties (particle density ρ and the specific surface area S_m).

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The effect of explosive shocking on the properties of fine titanium oxide TiO₂ and zirconium oxide ZrO₂ powder was examined. Experiments at two different pressures were conducted on anatase-type TiO₂ and monoclinic-rich ZrO₂ in which about 14% of the tetragonal phase was contained. The impact pressures induced in the powder by the shocks were estimated to be about 5GPa and 20GPa.
The crystallite sizes of both powders estimated from broadening of the X-ray line became smaller due to the explosive shock treatment. No sign of commiuntion was observed. The average particle diameters of the explosively shocked powders were, larger than those of as-received powders due to sintering. This indicates that smaller crystallite sizes were caused by the shock-induced defects present in the powders, not by small particle diameters.
TiO₂ and ZrO₂ were respectively densified to 98 and 96% of the theoretical density by the shock compression of 20GPa.
About 30% of anatase-type TiO₂ was transformed to rutile-type. The tetragonal phase normally observed at higher temperatures of ZrO₂ was all changed to a monoclinic plase by the impact pressure of 5GPa, but about 25% of the tetragonal phase was again produced by the impact pressure of 20GPa.
The sintered density of explosively shocked TiO₂ became lower than that of as-received powder. The sintered body of explosively shocked ZrO₂ has fewer cracks than that of as-received powder probably because of the existence of the tetragonal phase.

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The solubility of gases in various kinds of solvents was correlated with the molecular parameters of a gas and a liquid, as expressed in the Lennard-Jones potential equation.
The correlation was based primarily on the random packing structure model of particulate materials having a range of sizes; and the solubility was expressed in terms of the molecular potential ε, size σ, and shape λ at room temperature and atmospheric pressure, within errors of about 37%.

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