Reaction between vitreous SiO2 and Al
Rate of reaction between Al and SiO2 in vitreous silica or in silicate was measured between 500°C and 600°C in air or vacuum. The reaction couples used in the study were aluminum-silica glass and aluminum-Shirasu Balloon, which was a hollow microsphere of aluminosilicate glass. In the present study, it was found that the rate determining stage of the reaction between SiO2 and Al was associated with breaking of a Si-O bond. Apparen+ activation energies of the reaction are 56.5cal/mol for the silica glass-aluminum system and 78.7cal/mol for the Shirasu Balloon-aluminum system, respectively.
Abstract Partly oxidized Ag films deposited on glass substrates were found to exhibit significantly different reflectance properties for either s- or p-polarized incident light under conditions of total internal reflection. The measured reflectances depend strongly on angle of incidence and wavelength of light and are sensitive functions of the Ag and Ag 2 O layer thicknesses. For pure and slightly oxidized Ag films we observe the evolution of the well known surface plasmon resonance, whereas for Ag films with an increasing oxide layer a new resonance is observed in s-polarization. We account for all these effects by modeling the oxidized Ag film as a glass/Ag/Ag 2 O/air system and using the recently published optical constants for Ag 2 O.