Prediction of particle concentration distribution from a slot die is presented. The uniformity of particle concentration distribution is predicted by the particle trajectory in a slot die. In order to depict the movement of particles in the slot die, we coupled the one-dimensional flow equations in a slot die and Stokesian sedimentation equation. It is concluded that Reynolds number and particle diameters affect the uniformity of the particle concentration from the slit, and the predictions using the presented model agree with the experimental results.

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In order to enhance the image quality, the relationship between the powder behaviors of toners and developers with different toner concentrations was analyzed quantitatively using the rotary shearing tester with conical rotor ; further, and the effects of the fluidity of developers on the development characteristics (the relationships between the development charge Q and the surface potential of a photoconductor V and between the amount of developed toners M and V) were examined. As a result, it was found that there was a strong correlation between the macroscopic shearing torque of the toners and the macroscopic shearing torque of the developers. Moreover, it was understood that the macroscopic shearing torque of the developers and the equivalent thicknesses of the developer layer D_b showed a linear strong positive correlation. Subsequently, the relationship between the charge-to-mass ratio of the toner particles q / m and the flow properties was examined. The value of q / m could be given by the slope of the plot of Q and V, tan Θ₁ and the slope of the plot of M and V, tan Θ₂. As a result, the macroscopic shearing torque of the developers and q / m showed a linear negative correlation. Thus, it was confirmed that the development characteristics could be quantitatively controlled by the flow properties of the developers.

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A variety of ZnO nanoparticles differing in their morphology were prepared by precipitating method where ZnCl₂ aqueous solution was dropped into aqueous alkali solution. The prepared ZnO nanoparticles were employed for photocatalytic degradation of methylene blue dye. When NaHCO₃ aqueous solution was used for the preparing operation, the precipitate consisting of basic-ZnCO₃ was calcined at 300℃ for turning it to ZnO nanoparticle. A decrease in a ZnCl₂ / NaHCO₃ equivalent molar ratio from 0.4 to 0.05 caused an increase in a surface area of the ZnO nanoparticle formed into uneven shape, from 19.6 m² / g to 79.8 m² / g. Although the increase in the surface area enhanced the photocatalytic activity, this activating effect was weakened obviously beyond 50 m² / g of the surface area. On the other hand, NaOH aqueous solution was used for the preparing operation with the result that ZnO nanoparticle shaped like rod was directly precipitated. The use of the diluted NaOH aqueous solution allowed ZnO nanoparticle to be shaped like nut. It seemed that the photocatalytic activity of ZnO nanoparticle was independent of its geometric shape. Additionally, the photocatalytic degradation of acetaldehyde was carried out for studying practical use of ZnO nanoparticle as a photocatalyst.

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In this review, experimental and numerical studies for heterogeneous chemical reaction, volume reduction and thermal conduction during pyrolysis of biomass in a packed bed were reported. The yield of solid component could be reproduced by the calculation using the Millers reaction model even if the heating rate and the lignin content changed. The volume reduction of the packed bed for softwood was closely related with the pyrolysis and divided into three regions ; i） region of dehydration from biomass, ii） region of pyrolysis of cellulose and iii） region of pyrolysis of lignin. The reduction process was explained by not only the Miller's chemical reaction model with dependence of gas volume in the bed on the temperature but also the reversible first-order chemical reaction model. The calculated gas flow rate, taking into account the effect of the temperature distribution in the packed bed, agreed with the experimental results except for the flow rate due to tar decomposition. The time course of the average gas temperature in the packed bed was partly agreed with the calculation in taking account of porosity change. Furthermore, the temperature could be reproduced by the calculation with having the effect of volume reduction.

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Herein the author introduces our recent research on a mechanical grinding of natural graphite particles and its compound. In the first topic, we propose a production scheme for conductive films composed of thin graphite sheets with high crystallinity and polymeric resin. Crystalline graphite sheets are successfully produced from natural graphite powder by solution-phase synthesis of graphite intercalation compounds （GICs）, following a wet planetary ball milling under mild conditions. Some composite films derived from the phenolic resin and ground products of GIC display much higher electrical conductivities compared to the film from the feed graphite particles while using a small amount of graphite sheets. This composite film will be applied to functional plywood which produces constant heat by applying a voltage to the composite film between wood sheets. In the second topic, we produce high-crystallinity graphite particles having high specific surface area by means of planetary ball milling under the well-controlled atmosphere. Well-defined PtCl₄-GIC is synthesized by only use of such graphite particles. The resulting GIC is a candidate precursor for the hydrogenation catalyst.

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