Atsushi Hitomi

Catalytic reforming of methane to syngas in an oxygen-permeative membrane reactor

For fuel cell applications, partial oxidative reforming of methane to syngas, hydrogen and carbon monoxide, was performed via a dense oxygen-permeative ceramic membrane composed by both ionic and electronic conductive materials. The modification of Ni-based catalyst by noble metals was investigated to increase oxygen permeation flux and decrease carbon deposition during reforming reaction. The role of each component in catalyst was also discussed.

The Effect of Reoxidation on Thermal Shock Resistance of SrTiO3-Based Varistors

The fabrication processes of SrTiO3-based varistors were investigated to obtain highly thermal-shock-resistant devices. It has been found that the reoxidation conditions are strongly related to the thermal cracking ratio (%) of the varistors. A large compressive stress was generated on the varistor surface by reoxidation, consequent upon the lattice parameter difference between its surface portion and its internal portion. This residual stress on the surface is thought to be the key factor of the achieved thermal-shock-resistance.