A method of homogeneously packing powder into a cell is in the process of being developed. In this paper, as a first step in the discusssion of homogeneous powder packing, the powder porosity in the interference region between two points feeding to a cell is experimentally observed and analysed by an X-ray radiograph. Especially, the effect of the powder feeding outlet diameter and powder feeding height on the powder porosity in the interference region are noticed experimentally.
The following results are obtained:
1) For silica sand, dependency of the powder feeding diameter on the powder porosity in the interference region is found to be larger than that of the powder feeding height. The powder porosity shows a lower value than that of the neighbouring region.
2) On the other hand, for alumina powder, the powder porosity in the interfernce region shows an almost constant value, which is larger than that of the neighbouring region, independent of the powder feeding diameter and the powder feeding height.

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Acoustic emission from the shear flow of granular materials was observed during a direct shear test. Because of this, a method of predicting the failure of granular materials by emission count was established. Acoustic emission from the granular bed occurs due to the rupture layer formed periodically in the bed. The correlation between the emission count rate and the vertical stress in a granular bed was obtained. The emission count rate was also related closely to shear speed. The information on the failure of the granular bed was obtained by the parameters of acoustic emission.

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The accomodation of a three-Parameter adsorption equation derived on the basis of statistical thermodynamics in the model of localized adsorption for monolayer and non-localized adsorption for the upper adphase over the 1st layer to the experimental adsorption isotherms has been investigated by N₂ adsorption isotherms on carbon black with a micropore which is preadsorbed by nonane. The three-parameter adsorption equation agreed well with experimental isotherms in the range of relative pressure from 0.01 to 0.6. These had wider range of agreement than with the BET equation i. e., in a range from 0.05 to 0.2. Accordingly, the upper adphase over the monolayer for the formation in an intermediate relative pressure range after the completion of the monolayer was perceived not to form stacked layers like the localized multilayer proposed by BET theory, but to form preferably a non-localized mobile adphase. The surface areas obtained from the three-parameter adsorption equation, a Huttigtype adsorption equation and BET equation, agreed with each others within 15%, respectively. These surface areas were investigated by comparison of the results from α_s-plots of these experimental isotherms. Since the surface areas obtained from the isotherms in the reduction of the micropore amount from α_s-plot in the application of each adsorption equations agreed with the outer plane surface areas from the slope of the linear portion in α_s-plots, the micropores would be filled up in an extremely low relative pressure range. The surface areas obtained from the three-parameter adsorption equation was perceived to be reasonable.

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In order to clarify how gases in the atmosphere affect the surface of a ZnO crystal, the heating desorption analysis of ZnO fine particles was carried out using FID and TCD gas chromatography.
The state of O₂ adsorption on the needle-like and prism-like ZnO fine particles synthesized by the gas-phase oxidation of Zn vapor was examined.
The results revealed that three desorption peaks occurred with the heating of ZnO fine particles, and the needle-like particles had a large amount of chemisorbed oxygen in any peak, compared with those of the prism-like particles.
The basic zinc carbonate was formed on ZnO fine particles on exposure to the air. CO₂ and H₂O released from the particles were examined by heat desorption analysis. From the starting temperature of desorption and the composition ratio of CO₂ and H₂O, it was concluded that the surface product of the ZnO fine particles was probably Hydrozincite. The surface products affectied affected the acidity of the ZnO fine particles.

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Using the fractal concept, the energy E required for the size reduction of a solid is explained by a Fractal-Rittinger equation dE/d (d_p) ∝ d_p^D-4, where d_p is particle diameter, and D is the fractal dimension ranging from 2 to 3. Lewis' and Holmes' equation, which is generally applicable to the comminution of solid material but when the physical meaning of the parameters is uncertain, is involved in the Fractal-Rittinger equation with the fractal dimension of the surface of the size-reduced material.
The fractal dimensions calculated from the literature values of the exponents in Lewis' and Holmes' empirical equations agree well with those experimentally obtained for the corresponding materials.

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