Papers by Author: Byung Kyu Choi

Abstract: This research investigated the water purification performance of thin film with anatase phase TiO2 powder having good photocatalytic property using an innovative aerosol deposition method at the normal room temperature. Fresh raw powder was dehydrated for good dispersion of TiO2 powder. To suppress the formation of second particle, the powder was dispersed for 90 minutes in alcohol bath with ultrasonic treatment and then desiccated. The average grain size of particle was identified to be 1µm in TiO2 thin film deposited on stainless steel mesh by scanning electron microscopy (SEM). The anatase phase of TiO2 thin film was investigated by X-ray diffraction (XRD). The anatase phase of fresh raw powder was favorably maintained after aerosol deposition treatment.

Abstract: Recently, composites are widely used for interior panel of the transportation facilities such as railway vehicle, ships and aircraft, etc. These interior composites panels are often made by vacuum bagging, hand lay-up method and autoclave, etc. In this study, we carried out tests for the evaluation of material properties of the panels under more severe conditions than real environment to evaluate the dimension stability of the interior composite panels. Two sets of panels, one made by hand lay-up method with glass mat/polyester resin (Type 1), and the other, by vacuum bagging method with epoxy prepreg/NOMEX (Type 2) are exposed to the low temperature, high temperature and room temperature. And then we measured the dimensions of the strained panels. To monitor the characteristics of cured resin, we used DSC (Differential Scanning Calorimeter). It was observed that Type 2 has higher mechanical properties and dimensional stability than Type 1.