Polymer electrolyte fuel cell (PEFC) is the most promising fuel cell being developed for stationary and automobile applications because of the high energy efficiency and environmentally-friendly power source. However, there still remain many problems regarding the cost and durability to be solved for the widespread commercialization. In this review paper, the problems of the material degradation related to PEFC are presented as well as the present state of the development of PEFC. The experimental results of fundamental study that author has performed as a NEDO project on corrosion of Pt catalyst and carbon support of PEFC are also presented.
It is necessary to avoid settlement of marine life in cooling system of power station and on ship bottom. There are two factors which affect settlement of barnacles, such as mechanical and chemical factors. Cyprid larvae swim around and explore favorite surface with their first antennas. When they detect the surface, they test it and settle on. This study focused on the relationship between the micro-texture of substrate surface and settlement behavior. The number of settlement of barnacles on controlled micro-textured surfaces and polished surface was measured with a specially developed laboratory testing cell. Results showed that the surface topography strongly affects the settlement behavior of barnacles. This suggests that the existence of optimum surface topography discourages larval settlement.
The corrosion morphology of carbon steel varies with environmental factors in fresh water. General corrosion and localized corrosion are known as the major morphologies. In the case of the general corrosion, the corrosion monitoring and the life prediction of the metal can be carried out without the difficulty. However in the case of the localized corrosion, the precise corrosion monitoring is difficult and the unexpected trouble like water leakage may happen. Therefore, the diagnosis method of water quality for carbon steel corrosion in fresh water is required strongly. In this study, we propose a simple method to classify the corrosion category of the carbon steel in the fresh water by combining potentiodynamic polarization curve measurement and potentiometry at a constant current.