Loading effects of silver oxides upon generation of reactive oxygen species in semiconductor photocatalysis.

Superoxide anion radical (O(2)(-*)) and OH radical generations in suspensions of Ag metal-, Ag(2)O-, or AgO-loaded TiO(2) and BiVO(4) photocatalysts in alkaline conditions (pH 12.0) were examined by means of a luminol chemiluminescence (CL) technique and a spin-trapping fluorescence one in which terephthalic acid reacts with an OH radical to afford the highly fluorescent 2-hydroxyterephthalic acid (TAOH), respectively. The observed luminol CL intensity was remarkably enhanced by the AgO loading on TiO(2) as well as BiVO(4).

Fluorescence on-off switching mechanism of benzofurazans.

Many fluorescent reagents with a benzofurazan (2,1,3-benzoxadiazole) skeleton have been developed and widely used in bio-analyses. In this study, we try to elucidate the fluorescence on-off switching mechanism of three fluorogenic reagents and their derivatives. Ten 4,7-disubstituted benzofurazans were used for this purpose and the measurements of their fluorescence, phosphorescence, photolysis, and time-resolved thermal lensing signal in acetonitrile were obtained in order to understand the relaxation processes of these compounds.