A numerical simulation model was developed to analyze the powder composite process by Discrete Element Method (DEM). The effects of an existence of scraper and its scraper angle were discussed using the simulation in terms of the impact energy and mixing degree of particles, which would be correlated with composite process. The particles motion in the powder composite process is strongly dependent on the existence of scraper and its scraper angle. The impact energy with the scraper is around two times larger than that without scraper and impact energy reaches the maximum value at 180 degree. In addition, scraper has a major effect on the mixing performance. The mixing index with the scraper is around two times higher than that without scraper.
  The simulation model proposed will be used to understand powder composite process and optimize operation conditions.

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  Herein we produce high-crystallinity graphite particles having high specific surface area by means of planetary ball milling under the well-controlled atmosphere. PtCl₄-graphite intercalation compounds (PtCl₄-GIC) are successfully synthesized as the catalyst for hydrogenation reaction of gaseous 1, 3-butadiene. The effect of specific surface area and crystallinity of ground products on the synthesis for PtCl₄-GICs is reported. Well-defined PtCl₄-GIC was synthesized only by use of the ground graphite particles which have both high specific surface area and high-crystallinity. The resulting GIC is a candidate precursor for the hydrogenation catalyst.

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  A two-dimensional direct numerical simulation is applied to spray jet flames, and effects of background pressure and droplet size on soot formation behavior is investigated in detail in the mono-dispersed droplet size conditions. N-decane (C₁₀H₂₂) is used as a liquid fuel, and droplet motion is calculated by the Lagrangian method. The extended flamelet/progress-variable approach is emplyed for the turbulent combustion chemistry. A kinetically based soot formation model with the flamelet model is employed to predict soot formation. The results show that the soot is mainly formed in the large vortex structure in the downstream region and the soot formation behavior is significantly affected by the pressure. It is found that the soot volume fraction and soot particle diameter increases with increasing the pressure due to that the concentration of soot precursor increases and the soot particle's residence time is enlongated in the structure.

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  Carbon black / phenol resin nanocomposite particles were prepared by mechanical treatment. Bulk bodies were fabricated using these nanocomposite particles by uniaxial pressing and slip casting technique to control the electrical conductivity. Scanning electron microscope (SEM) observation showed dense and thick layer of carbon black were formed on the phenol resin particle by mechanical treatment. electrical conductivity of the bulk body prepared using hollow carbon black was higher than that using dense carbon black. The bulk body fabricated by slip casting technique showed higher electrical conductivity than that by uniaxial pressing because of development of percolation structure due to higher coordination number of nanocomposite particles.

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