This study examines the role of the nano- and micro-particle ratio in dispersion stability and mechanical properties of composite resins for SLA(stereolithography) 3D printing technology. VTES(vinyltriethoxysilane)-coated ZrO2 ceramic particles with different nano- and micro-particle ratios are prepared by a hydrolysis and condensation reaction and then dispersed in commercial photopolymer (High-temp) based on interpenetrating networks(IPNs). The coating characteristics of VTES-coated ZrO2 particles are observed by FE-TEM and FT-IR. The rheological properties of VTEScoated ZrO2/High-temp composite solution with different particle ratios are investigated by rheometer, and the dispersion properties of the composite solution are confirmed by relaxation NMR and Turbiscan. The mechanical properties of 3Dprinted objects are measured by a tensile test and nanoindenter. To investigate the aggregation and dispersion properties of VTES-coated ZrO2 ceramic particles with different particle ratios, we observe the cross-sectional images of 3D printed objects using FE-SEM. The 3D printed objects of the composite solution with nano-particles of 80 % demonstrate improved mechanical characteristics.

Vitamin A, particularly all-trans retinol is excellent for anti-aging but is sensitive to oxygen, heat and light and has low solubility in water. In this study, retinol was encapsulated within oil-in-water (O/W) emulsion, protein-based particle and cycloamylose(CA). And then, it confirms that retinol contained in each delivery system is stable to UV, pH, and temperature and finally measures bioaccessibility. O/W emulsion was compared according to the type and concentration of emulsifier. UV stability of retinol increased with increasing oil concentration. More than 10 wt% of oil was required to maintain stable retinol (50% residual after 24 hours of irradiation). Using anionic emulsifier, retinol had unstable storage stability regardless of oil concentration and temperature. Protein based particle was compared according to the type of stabilizer and polysaccharide. UV stability of retinol was highest in pectin-coated particles. However, 20% retinol remains after 6 hours of irradiation and is vulnerable to UV compared to other delivery systems. In pH stability, pectin-coated particles also stably retained retinol. Inclusion complex of retinol and CA was compared according to the concentration of CA. When CA was used, the residual amount of retinol to UV was high (50% residual after 24 hours of irradiation) regardless of the concentration of the host molecule. In the case of storage stability, retinol remained significantly higher regardless of temperature when cycloamylose was used. It was finally confirmed bioaccessibility each of retinol delivery system. O/W emulsion was determined by emulsifier type, protein-based particle by coating agent, and inclusion complex by CA concentration. All O / W emulsions retained more than 50% retinol, protein based particles retained more than 80% retinol, and inclusion complex retained more than 70% retinol. The bioaccessibility of pure retinol is about 20%. This study provides important information for designing effective delivery systems for improving the stability of retinol.

The purpose of this paper was to investigate the effect of a high-energy milling (HEM) process on the particle morphology and the correlation between a thermal treatment and tetragonal/monoclinic nanostructured zirconia powders obtained by a precipitation process. To eliminate chloride residue ions from hydrous zirconia, a modified washing method was used. It was found that the used washing method was effective in removing the chloride from the precipitated gel. In order to investigate the effect of a pre-milling process on the particle morphology of the precipitate, dried Zr(OH)4 was milled using a HEM machine with distilled water. The particle size of the Zr(OH)4 powder exposed to HEM reduced to 100~150 nm, whereas that of fresh Zr(OH)4 powder without a pre-milling process had a large and irregular size of 100 nm~1.5 μm. Additionally, modified heat treatment process was proposed to achieve nano-sized zirconia having a pure monoclinic phase. It was evident that two-step calcining process was effective in perfectly eliminating the tetragonal phase, having a small average particle of ~100 nm with good uniformity compared to the sample calcined by a single-step process, showing a large average particle size of ~300 nm with an irregular particle shape and a broad particle size distribution. The modified method is considered to be a promising process for nano-sized zirconia having a fully monoclinic phase.

The relationship between storage stability and calcium contents extracted from anchovy according to particle sizes was investigated in this paper. The results are as follows; 1. The acid value (AV) and the peroxide value (POV) of anchovy were in the rank order of whole anchovy$lt;35$lt;50$lt;80 mesh by particle sizes and 6$lt;12$lt;18$lt;30 months by storage term. 2. The Calcium (Ca) and Phosphorus (P) contents extracted from anchovy were in the rank order of whole anchovy$lt;35$lt;50$lt;80 mesh by particle sizes and 10$lt;20$lt;30 minutes by heating time. The extracted amount of Ca was the largest when anchovy particles with 80 mesh were heated for 30 minutes. In that case the amount of Ca in the anchovy stocks was 52.54 mg. 3. The amount ratio between Ca and P was in the rank order of 30$lt;20$lt;10 minutes by boiling time and indicated 1:3.99-5.16 by each part. The lowest ratio of Ca to P was 1:3.99 when anchovy particles with 80 mesh were heated for 30 minutes. 196