A perturbed-hard-sphere equation of state (PHS-EOS) was applied to correlate the solubilities of high boiling compounds such as coal liquefaction products in supercritical fluids. A suitable mixing rule for the constants contained in the PHS-EOS is needed to apply the equation of state to a mixture composed of high boiling compound and supercritical fluid. In this study, mixing rules for the constants were examined and discussed. It was found that a local composition mixing rule with three characteristic parameters introduced into both molecular attraction and molecular size terms gives a good result because the solubility is quite small near infinite dilution.

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This paper deals with the relationship between the porosity and the flow pattern of bulk solids in a bin.
The author first investgated the porosity of a bin which was achieved by central or peripheral feeding, and observed the flow pattern under each set of filling conditions during the discharge. From the results, it was found that the porosity of the bed achieved by peripheral feeding had a value considerably smaller than that in the case of central feeding. The flow pattern finally took on the form of a funnel.But when porosity increases in proportion to the rate of feeding, the result is mass flow. In such a case, a certain amount of time is required for particles to become detached from the walls of a bin and moved along with the flow and a pulsating pressure occurs near the hopper gate.
On the other hand, in the case of central feeding, the flow is a perfect mass flow in which nearly all particles along the walls of the bin move together at the commencement of the discharge.

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In the fundamental research of optical materials, it has been necessary to measure their polarized functions. Especially, a little birefringence in the ultra thin film such as Langmuir-Brodgett film and its dynamic characteristics such as liquid crystal have not had clearly data and many discussions. Therefore, we are developing a high sensitive measurement system of dynamic birefringence using optical phase modulator (Pockels device) and two Faraday rotators (Faraday device). This report describes some basic workings of the new high sensitive measurement system. It was possible to measure a small birefringence (retardation 5×10^-3 rad) and fast axis angle of sample.

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The XPS and AC conductivities of a-Si_xC_1-x: H films prepared by the plasma CVD method from silane and methane gases were measured. The separation of the XPS spectra into several peaks revealed the nature of the chemical bonds of silicon and carbon atoms. The coordination of the carbon atom was fourfold in the silicon-rich films, while the threefold coordination was dominant in carbon-rich films. Films prepared from hydrogen-diluted gas contained more carbon atoms with fourfold coordination than those prepared from argon-diluted gas. AC conductivities of the films with silicon content 0.7<x<0.9 were explained in terms of the correlated barrier hopping (CBH) model, the densities of hopping sites were estimsted to be 10¹⁷-10¹⁸cm^-3. AC conductances of the films with x>0.9 above 300K were discussed in terms of the trap-released model. The densities of states at the Fermi level were estimsted at-10¹⁶cm^-3eV^-3 and the Fermi level was in the midgap.

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A breaker is a machine which is used to break rocks in the mining and public works. In the field of these works, it is known that the oil hydraulic breaker is improved when the outlet resistance of oil flow increases suitably. However, there are very little quantitativa data on the influence of the outlet flow resistance.
In this paper, the perforemance test of a commercial oil hydraulic breaker is treated, and the influence of the outlet flow resistance is examined theoretically and experimentally. It is clarified that there is the optimum outlet flow resistance.

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Vacuum evaporation method is a promising technique to prepare metallic magnetic fluids with high saturation magnetization. In the method, ferromagnetic metals or alloys are evaporated in vacuum and are deposited onto the surface of oil containing surfactant, then the products are subjected to a heat treatment to grow the particles up to the size desirable for magnetic fluids.
In this work, such the effects of the heating process on the Co magnetic fluids were investigated in further detail.
The particles of Co with diameter distributed arounds 2 nm before heating grew into the size of about 5 nm and were agglomerated after the heat treatment. The growth rate of particles increased with decrease of the concentration of the surfactant contained in the oil. From infrared spectra, the surfactant layer protectingthe particles were confirmed on the sample before heating. After heating, however, the infrared spectra characteristic for the surfactant layer became obscure ones. The agglomerated particles can be redispersed into a stable dispersion system by adding the surfactant. In this manner, Co magnetic fluids which has the highest saturation magnetic flux density of 680 G was obtained.

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Organic material exhibiting a novel ferromagnetic behavior were obtained by the pyrolysis of the mixture of o, m, p-phenylenediamine (PDA) and 2, 4, 6-triphenoxy-1, 3, 5-triazine (TPTA) at 500-1000°C. The content of ferromagneticlike part was largest in the sample prepared at 600°C. The larger values of spin concentration N_s (1.18×10¹⁹ spins/g) and saturation magnetization Ms (6.24×^-1 emu·G/g) have been found in the product obtained from TPTA/m-PDA than those from TPTA/o-PDA and TPTA/p-PDA. Ferrimagnetic behavior was observed in the material obtained by the pyrolysis of TPTA/BG (benzoguanamine), TPTA/melamine (M), M/-PDA and BG/m-PDA containing nitrogen atoms. The results are tentatively discussed in terms of parallel spin orientation of nitrogen radicals.

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Recently, the ceramics are used in various fields. Especially, electro ceramics which have specific electric function are taken notice. Then, electro ceramics manufacturing process become more and more important in industry.The ceramics manufacturing process consists of various kinds of unit operations, and can be considered as combination of forming process and sintering one. However, basic relation between forming process and sintering one has not yet been elucidated. In other words, the effect of the homogeneity of initial bulk density distribution in the forming cell on the homogeneity of bulk density of powder compact or sintered powder one has not yet discussed.
In this paper, the effects of initial bulk density distribution on the bulk density distributions of powder compact and sintered powder one are experimentally discussed by using the X-ray radiograph system. As the result, these bulk density distributions of powder compact and sintered one are greatly effected on the initial bulk density.

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The particle beds analyzed in this paper consist of comparativly large spherical glass beads assemblies at low consolidations. At the condition that the degree of freedom of particle motion is not zero, various constants of particle bed change discontinuously with increasing normal pressure, and a gredient of constants to normal pressure decreases with increasing normal pressure. It is guessed that properties of the particle bed change from those of discontinuous body into those of continuous one. The fact indicates that assumption of Janssen or other equations used in structural design of storage vessel is inadequate for comparatively large particle assemblies at least.
The behaviors of particle in a shear box are thought of as three processes for instance. In the first, the particl motions are completely free, and then each particle is able to both spin and move straight. In the second, the particle motions are constrained partly, and then each particle subjected to shear force is able to only spin or move straight. Straight motion may be constrained earlier than spinning motion on increasing normal pressure. In the third, the particle motion is constarained completely, and particle assemblies subjected to shear force glide on a particle surface.

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Hydroxyapatite (HAP, Ca₁₀ (PO₄) ₆ (OH) ₂), is an important mineral component of hard tissues such as teeth and bones. Therefore, when used in an implanted artificial hard tissue, HAP is expected to show a high affinity for natural hard tissue in situ. However, the bioconvertibility of HAP is affected by the physicochemical properties such as crystallinity, specific surface area, impurities, adsorption and dissolution, depending on the method of synthesis. In this review, the relations between the various kinds of synthesis for HAP and the physicochemical properties are discussed to provide basic information for using biomaterials, and the several application studies about HAP are introduced.

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