Recombination of hydrogen over Pt/TiO2 catalysts under ambient conditions
It has been reported that H2, which is very explosive gas in nuclear power plants. Therefore, in this study, we prepared a catalyst under different conditions its ability to oxide H2 at room temperature. And it was characterized by means of X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and CO-chemisorptions. The catalyst consisted of Pd or Pt/TiO2 and was prepared by the wet impregnation method. To assess the effects of pretreatment, the catalyst were prepared at 873K in a hydrogen atmosphere and at 673K in air atmosphere. When the conversion rate of H2 to H2O was compared for these catalysts, the catalyst prepared in hydrogen atmosphere displayed the perfect conversion rate at room temperature and pressure.
Control of titania nanodomain size as a route to modulate SMSI effect in Pt/TiO2 catalysts
Platinum based mesostructured SiO2 supported TiO2 nanoclusters (TiO2 content ranging from 10 to 50 wt.%) were synthesized and characterized. Titania nanodomains (< 4 nm) dispersed in the silica porosity are obtained. Derived 1 wt.% Pt/xTiO2-SiO2 nanocomposites were tested in the cyclohexane dehydrogenation reaction, a structure insensitive reaction to evaluate metal-support interaction. Pt/xTiO2-SiO2 nanocomposites display largely higher SMSI effect than measured over classical Pt/TiO2 P25 catalyst. While platinum particle size is found to be affected by the titania loading in the composite, similar SMSI effect is measured for all solids displaying similar TiO2 crystal size. Titania crystal size is evidenced as an important parameter allowing a control of the SMSI effect: the lower the crystal size, the stronger the metal-support interaction.
The incidence of dead and dying fish in the Moray Firth, September 1963
Dead and dying fish were reported from the Moray Firth during a period of 15 days in September 1963. The initial mortalities were in the inner Firth, but they later spread outwards, especially eastwards along the southern shores of the Firth. Mass mortalities of the lugworm (Arenicola marina) also occurred in Scottish waters in 1962 and 1963, and at Balintorein Easter Ross fish and lugworm mortalities were contemporary.