We propose a new parallel implementation method for particle contact detection processes in the Discrete Element Method (DEM). Conventional implementations require mutual exclusion, which results in their parallel performance being reduced when the execution is highly threaded. By using multicolor contact grids, our implementation method, called the Multicolor Particle Contact Detection Method, accomplishes parallel execution without mutual exclusion. The results of an evaluation conducted indicate that the performance of our proposed method is superior to that of conventional methods.

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Functional materials have been applied in various fields such as pharmaceutical, cosmetics and foods. Mechanochemical process via grinding has been used as a promising method to create functional materials. However, the mechanism of mechanochemistry is too complex to comprehend completely despite utilizing in a practical way, because mechanochemical reaction comes concurrently with fine particle, amorphization and radical formation. It is necessary to understand the effect of milling process on both the structural change and radical formation to design the composite functional materials.
The characteristics such as size reduction and structural change of alanine particles by dry-grinding process were examined from the relationship between degree of activation and operating conditions. Morphology of alanine particles were evaluated using scanning electron microscope. Crystallinity of alanine particles were determined by X-Ray Diffraction and differential scanning calorimeter. Change of radical strength was investigated by means of electron spin resonance.
Size reduction of alanine particles was affected significantly by the rotation speed ; values over 400 rpm produced agglomerated particles. The amorphization of alanine particles progressed with increasing the rotation speed. The radicals of alanine particles dry-milled by grinding were formed in the low speed range.

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Sustainable processing for Platinum nanoparticle was developed by novel ultrasonic and microwave liquid-solid reaction. Platinum oxide as metallic source and water based solvent were used in this system. This system can be synthesized 2-3 nm Platinum nanoparticle in short time and non-waste, so low-pricing of Platinum nanoparticle is realizable. By using water - ethanol mixed solvent, it can obtain dispersant-free Platinum nanoparticles suitable for catalyst, etc. This review illustrates the features and benefits of this system by comparing with the traditional nanoparticle synthesis methods and summarizes fabrication of nanoparticle related materials for high value-added and practical applications.

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This paper describes technique to control nanoparticle structure and array. As the first part, a modified inorganic template was introduced to prepare skeletal silica nanoparticles with unique structure composed of silica nanoframe and wide square windows. Affinities between modifying organic acid, silica source, and reaction medium are important factors for precise control of frame structure. As the latter part, a novel nanoparticle array technique based on a micro-phase separation was proposed. By only solvent vaporization, polymeric guide for nanoparticle array forms through phase separation into polar and non-polar phases. This separation flow arrays silver nanoparticle as a three-dimensional network. These two proposed techniques can be valid to maximize nanopaprticle functionalities.

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