The effect of microstructure in the vicinity of ferrite grain boundary in Ca-La-Co M-type ferrite on coercivity was investigated. According to Spherical Aberration Corrected Scanning Transmission Electron Microscopy (Cs-STEM) analysis, the Ca concentration in the vicinity of ferrite grain surface of the sintered body prepared under rapid cooling was found to be lower than that in a sintered body prepared under gradual cooling at the rate of −300 K/h. Considering that Co concentration was high in the region where Ca concentration was low as was found by Electron Probe Micro Analyzer (EPMA) analysis, it is suggested that the Co concentration was high in the vicinity of the ferrite grain surface prepared under rapid cooling, thereby enhancing crystal magnetic anisotropy in the vicinity of ferrite grain surface, which contributed to improvement of coercivity.

In this research, shot-blaster apparatus is intended mechanical milling apparatus by using air blast shot peening method. Normally, Alumina or abrasive powder is used as media particle to clean the product surface in the shot-blaster apparatus. In this paper, SUS304L stainless steel powders, the most widely used austenite stainless steel, were intended as shot-blaster media. This SUS304L powder media hit the tungsten carbide by high pressure from air compressor so that is deformed severely. The SUS304L compact was made by spark plasma sintering process. The microstructure and mechanical properties of the SUS304L compacts compared with the conventional compacts prepared using initial powders. The SUS304L powders have plastic deformation on the particle surface after shot-blasting. The deformed powders fractions are increased with increasing shot-blasting time. However, deformed powders fractions are stable at about 70 to 75% after 18 ks of shot-blasting time. The bimodal structure of SUS304L compacts can produced by shot-blasting process because small grain areas are observed in the sintered compact prepared from shot-blasted powders. The tensile results reveal that the SUS304L compacts made by shot-blasted powders exhibit high strength and especially high ductility compared with the conventional SUS304L compact.

An in-depth analysis of the morphology of Au nanorod/SiO₂ nanocapsules was performed by scanning transmission electron microscopy (STEM) imaging, secondary electron (SE) imaging, bright-field (BF) imaging, and high-angle annular dark-field (HAADF) imaging. These detailed analyses and high X-ray computerized tomography (CT) values provided key information for the administration of Au nanorod/SiO₂ nanocapsules into the blood of mice. Au, which is a heavy element, exhibits a high X-ray CT value. STEM images were recorded to clearly analyze the morphology of the Au nanorods and Au nanorod/SiO₂ nanocapsules. The results obtained from SE images, BF images, and HAADF images revealed that Au nanorods are covered by SiO₂ and that Au nanorod/SiO₂ nanocapsules are highly dispersed. Furthermore, 3D tomography reconstruction was performed by using STEM observation. Three-dimensional tomography reconstruction revealed a spatial structure and provided highly reliable information on the Au nanorod/SiO₂ nanocapsules developed in this study.