The KONA Award 2023

Kyoto Univ., and TITech.To initiate close research collaborations, WT went to KZU first as a 3-month JSPS visiting scientist in 1980.Starting from scratch, he could successfully manage to develop, create, and validate an innovative computer code that efficiently simulates the 3D convective diffusional deposition and dendritic growth of submicron aerosol particles on a single fiber using the Monte-Carlo method.In the 1980s, the filter performance and life expectancy of an entire HEPA and ULPA (fibrous air) filters, which are indispensable to clean rooms had to be determined experimentally because their theoretical investigations and simulations were impractical for submicron and nanosized particles that move by Brownian motion.WT and KZU collaborators not only experimentally validated the methodology but also extended the simulation to the more realistic case of polydisperse particles and then used it to predict their performance and the filter life.They could quadruple the service life of a high-efficiency electret filter by gradually varying the packing density from lowest at the inlet to highest at the outlet, compared to the conventional case of equal, uniform packing density.WT has co-authored 21 papers on this important area since 1981.In the area of nanoparticle synthesis (NPS), WT and his collaborators pioneered and extended the simple method of arc discharge in water to a variety of liquids (alcohols, alkanes, aromatics, etc.) and produced carbon and metal nanoparticles (NP) with higher yields and diverse morphologies (nanoballs, nanotubes, nano-onions, nano-whiskers, nano-horns, etc.) and novel characteristics.They further found that monoolein surfactant had an enhancing effect on carbon NP synthesis and the use of a metal-graphite electrode pair yielded metal-embedded CNP.They also investigated the synthesis of ZnS NP in microemulsion and of hydroxyapatite NP in an emulsion liquid membrane system as well as the effect of zinc precursors on the thermal and light emission properties of ZnO NP embedded in polyimide films.WT co-authored 24 papers on NPS since 2004.While pursuing these opportunities, he introduced and established powder/particle technology as an integrated/ comprehensive discipline in Thailand starting from