Ichihito Narita

In situ, Real-time Environmental SEM Imaging System Development for Water Splitting Reaction Using a Dynamic Light Illumination System

Photocatalysis plays a crucial role in water splitting reaction to generate the hydrogen, and particularly as catalysis which can reduce contamination. To date, this catalytic behavior has been studied by mathematical approaches and designed by computer simulation at the nanoscale. Although the determination of the active site is important to improve the catalytic function, direct observation of activity sites e.g. electron microscope has rarely been performed because of the vacuum conditions inside an electron microscope, in situ observation of photocatalysis behavior which requires liquid, light and dynamic controllability of the atmosphere still remains challenging. Therefore, it is desirable to develop a new electron microscopy in which we can change the environment under illumination of light with atmospheric pressure.

Three Dimensional Analyses of Degradation in PEMFCs

Proton exchange membrane fuel cell (PEMFC) is one of the candidate materials which can utilize the hydrogen without emitting greenhouse effect gas. However, the lifetime of PEMFCs is still short due to the degradation phenomena during operation. Previous studies suggest that applied temperature leads aggregation of supported particles and changes the distribution of metal nanoparticles and ionomers on carbon blacks. Recently, nanoscale distribution of these nanoparticles and ionomers attracts much attention to clarify these degradation mechanisms of PEMFCs and to improve the performance. Recent studies of distribution of the nanoparticles and ionomers of PEMFCs were investigated by tomography [1] and in-situ observation [2].

Dust Explosion Characteristics of Aluminum, Titanium, Zinc, and Iron-Based Alloy Powders Used in Cold Spray Processing

Compared to conventional thermal spray coating, cold spray processing typically employs finer, smaller-diameter metal powders. Furthermore, cold-sprayed particles exhibit fewer surface oxides than thermally sprayed particles due to the absence of particle melting during spraying. For these reasons, it is important to consider the potential for dust explosions or fires during cold spray processing, for both industrial and R&D applications. This work examined the dust explosion characteristics of metal powders typically used in cold spray coating, for the purpose of preventing dust explosions and fires and thus protecting the health and safety of workers and guarding against property damage. In order to safely make use of the new cold spray technology in industrial settings, it is necessary to manage the risks based on an appropriate assessment of the hazards. However, there have been few research reports focused on such risk management. Therefore, in this study, the dust explosion characteristics of aluminum, titanium, zinc, carbonyl iron, and eutectoid steel containing chromium at 4xa0wt.% (4xa0wt.% Cr-eutectoid steel) powders were evaluated according to the standard protocols JIS Z 8818, IEC61241-2-3(1994-09) sectionxa03, and JIS Z 8817. This paper reports our results concerning the dust explosion properties of the above-mentioned metal powders.