Dislocation loops observed in nonstoichiometric and stoichiometric (Ba,Ca)TiO 3 , and in stoichiometric BaTiO 3 sintered in a reducing atmosphere, were characterized by conventional transmission electron microscopy (TEM) under two-beam conditions and high-resolution TEM atomic structure analysis. Dislocation loops mostly lay on {100} planes with Burgers vectors of type ͗100͘. The dynamic behavior of these dislocation loops during the electron beam irradiation (EBI), however, was classified into two different types of dislocation loops: in A-site-excess (Ba,Ca)TiO 3 , contrasts of dislocation loops faded completely away; in BaTiO 3 and B-site-excess (Ba,Ca)TiO 3 , fine-line contrasts remained. Dislocation loops with Burgers vectors of type 1 ⁄2͗100͘ and the resultant crystallographic shear (CS) structure with a displacement vector of type 1 ⁄2͗110͘ after EBI were proposed to interpret residual line images. Disappearance of these line images in A-site-excess (Ba,Ca)TiO 3 strongly suggests preferential Ca ion site occupancy at the CS structure.

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By means of a model electrode method, it has been found that the ruthenium oxide highly dispersed on glassy carbon produces an extremely large surface charge density which corresponds to more than one proton adsorbs on every ruthenium loaded on the glassy carbon, if the charge was supposed to be caused only by the adsorption of proton on the RuO2.

Ultrafine particles of RuO2-1rO2 binary oxides with various compositions of Ru and Ir have been prepared by a sol-gel process consisting of hydrolysis and condensation of metal ethoxide ethanol solutions. The (Ru, Ir)O2 rutile-type solid solution of binary oxides was formed. High-resolution scanning electron microscopy micrographs of the Ru-lr binary oxides showed the spherical-like crystallites for Ru-rich oxides and needle-like ones for Ir-rich oxides. The particle size was the smallest for the binary oxide with comparable Ru-lr composition.

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