The photoluminescence (PL) intensities of Li-Ta-Ti-O:Mn⁴⁺ red phosphors were successfully improved under various oxygen partial pressures in an air-pressure control atmosphere furnace (APF). The Mn phosphors were synthesized using an APF and a conventional electric furnace (EF) with the composition formula Li_1.33Ta_0.67Ti_0.33O₃ as the host material. The effects of oxygen partial pressure on the Mn⁴⁺ ratio and crystal structure for the PL intensity were investigated. As a result, the PL intensity was enhanced under high oxygen partial pressure, showing about 2.6 times higher than the phosphor synthesized by EF.

Functional nanoparticles have been paid attention in various fields due to their specific properties such as transparency, and reactivity, quantum size effect. In this paper, present status and prospects of polymeric nanoparticles for drug delivery system and iron oxide nanoparticles for magnetic tapes are presented. First, polymeric nanoparticles prepared by a spherical crystallization method is reported. To understand the efficacy of polymeric nanoparticles to the biofilms, the interaction between bacteria and polymeric nanoparticles was revealed. Subsequently, cobalt ferrite nanoparticles prepared by solution chemistry method is reported. Different size and shape, magnetic properties of cobalt ferrite nanoparticles were studied according to the amount of surfactant. Finally, various electron microscopy methods which can be applied for characterization of functional nanoparticles are reported.

The number concentrations of liquid-borne particles are widely measured in various settings such as in semiconductor industries, clinical laboratory testing, pharmaceutical industries, and maintenance for industrial machineries. These industrial fields need quality control for the particle number concentration measurements by using reliable metrological standard. To establish the traceability in measurements of the particle number concentration from sub-micrometer to micrometer size range, we have developed an SI-traceable measurement method. We refer to this method as mass-measurement-type optical particle counting (M-OPC) method. The M-OPC method is based on single-particle optical particle counting method. Adopting two different type of optical particle counters having different measurable size ranges enables our calibration service to cover a wide range of particle diameters from sub-micrometer to micrometer level (600 nm–10 μm). This paper reviews the principle of the M-OPC method and the evaluation procedure of the particle number concentration including the uncertainty analysis. We also report the results of the verification tests for 600 nm, 2 μm, and 10 μm to confirm the validity of the M-OPC method in the above size range by using polystyrene latex (PSL) particles suspensions.

This review article focuses on a particle flowability during vibrating discharge and introduces a research for the effects of discharging vibration conditions and coating structures on improving the flowability in a smaller particle admixing system. In the research, main and admixed particles were mixed in various mass ratios to obtain coating structured particles, and the discharge particle flow rates of the coating structured particles were measured. In addition, coverage diameter, surface coverage ratio, and coverage height of the admixed particles on the main particle surfaces were obtained by image analysis of scanning electron microscopy and scanning probe microscopy. As a result, the admixing mass ratio and coating structure of admixed particles that gave maximum flowability were affected by the maximum value of the vibration acceleration.