The adsorption equation, which includes three parameters, has been derived presuming that the 1st layer is localized adsorption while the admolecules in an upper adphase region over the monolayer behave like compressed gas molecules, i. e. nonlocalized adsorption. This adsorption equation reseelted to the Hüttig-type adsorption equation presuming that the upper adphase region over the 1st layer is a liquid. This adsorption equation can predict the experimental isotherms. There may be classified as extended Type I isotherms where the amount adsorbed increases gently even after completion of the monolayer and shows a finite value of adsorbed amount at saturation vapor pressure. The equation can be used to predict the isotherms throughout nearly the entire range of relative pressure. The reasonable surface area, adsorption constant and surface fraction at saturation vapor pressure are found to be obtained from the application of the experimental isotherms to the adsorption equation thus derived. The BDDT double-layer adsorption equation derived from the model where both the monolayer and the upper adphase region over the 1st layer obeyed the localized adsorption model results in a Langmuir-type isotherm and predicts isotherms appreciably smaller than those of the experiment. The surface areas obtained when using a three-parameter adsorption equation show a much more reasonable interpretation than that from the BDDT double-layer adsorption equation. Thus, the property of the upper adphase region over the 1st layer is percieved to be a non-localized property in which admolecules in this region behave like a compressed gas molecule.

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The relationship between the average coordination number and the void fraction in a randomly packed system of uniform-sized spheres was investigated by for different kinds of computer simulated results to judge whether or not the coordination number could be uniquely estimated from the voidage. The relationship between the coordination number and the voidage depends on the types of the computer simulation program used our research results make it clear that the coordination number cannot be uniquely estimated from the void fraction. These computer simulated results were compared with the calculated results using some empirical or model equations which have already been reported in the literature. The model equations by Gotoh and Suzuki et al. and the empirical equations by Sunada et al. and Nagao were found to be in fairly good agreement with some of our simulated results.

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β-SiC ultra-fine particles were prepared by feeding reactant gases of CH₄ and SiH₄ into a newly developed R. F. thermal plasma furnace.
Amorphous β-SiC particles were deposited on the inner wall of the plasma torch, while crystalline β-SiC particles were found downstream of the tail flame of the torch.
By using TEM micrographs, the configurations of the crystalline β-SiC particles were found to be chain-like agglomerates which consisted of fine primary particles approximately 200Å-500Å in size.
The bonding states between the primary particles were presumed to be sintering from the magnified TEM micrographs.
Size distributions for agglomerate particles were determined by conventional particle size analyzers, and these results were compared with that obtained from the TEM micrographs.
A dynamic shape factor was introduced in order to account for the behavior of the agglomerates in the various media.

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