Light and temperature have considerable effect on the degradation of piroxicam in aqueous solutions. The pH and acetate buffer ions also affect the degradation process. The apparent first-order rate constants for the photochemical and thermal degradation of piroxicam have been determined as 2.04-10.01 and 0.86-3.06×10(-3) min(-1), respectively. The first-order plots for the degradation of pirox...

Este trabalho descreve o comportamento fotoquímico do pirazosulfuronato de etila em soluções aquosas. A fotodegradação do pirazosulfuronato de etila foi investigada pela primeira vez em dois comprimentos de onda de irradiação diferentes e valores de pH variando de 2,00 a 10,00. Os resultados mostram que a taxa de fotodegradação foi mais rápida em meio ácido do que em meio básico, quando pyrazos...

The photostability of tretinoin tocoferil was investigated under irradiation with three kinds of lamps, i.e., a cool white fluorescent lamp, a UV-A fluorescent lamp and a D65 fluorescent lamp. A combination of the cool white fluorescent lamp and the UV-A fluorescent lamp, and the D65 lamp having relative spectral power distribution similar to that of direct daylight, correspond to options 2 and...

The chemical and cost efficiency of the ozone with ultraviolet radiation (O3/UV) photochemical degradation of total organic carbon (TOC) was examined. The efficiencies were compared to other commonly used wastewater purification processes, hydrogen peroxide with UV (H2O2/UV) and titanium dioxide with UV (TiO2/UV). The O3/UV process appears to be the least cost-efficient process due to high chem...

The role of photochemical degradation of dissolved organic carbon (DOC) on UV transparency (280-400 nm) was investigated in three Pocono Plateau lakes. Diffuse attenuation coefficients (I&) in the epilimnia of these lakes varied seasonally (39-8 1% decline from maximum Z&,&, with minimum Kduv values occurring near summer solstice. Declines in K,,, corresponded to reductions in UV absorbance by ...