Contribution of the Photo-Fenton Reaction to Hydroxyl Radical Formation Rates in River and Rain Water Samples

Chemical Dosimetry System for γ-Ray Irradiation Based on the Formation of Phenol from Aqueous Benzene Solutions

“…Short-life-time reactive oxygen species and radicals, such as hydroxyl radicals, 4,5 NO radicals, 6,7 hydrogen peroxide, 8 and hydrate electrons, 8 are photochemically generated in environmental water by natural sunlight. The author and coworkers have investigated and described a determination technique for some reactive oxygen species and radicals.…”

“…The author and coworkers have investigated and described a determination technique for some reactive oxygen species and radicals. [4][5][6][7][8] For the determination of hydroxyl radicals, many chemical probe methods based on the determination of products formed by reactions between hydroxyl radicals and probe compounds have been reported. In these methods, benzene, 4,5,9 nitrobenzene, 10 benzoic acid, 11,12 terephthalate, 13 2-propanole, 13 methanol 11 and dimethyl sulfoxide 14 were used as the probe compounds.…”

“…The benzene probe method in which phenol formed from benzene and hydroxyl radicals is determined by HPLC is a simple, rapid, low-cost and highly sensitive method for determining the photochemical formation of hydroxyl radicals in environmental water. 4,5,9 The irradiation of aqueous solutions with ionizing radiation produces hydrogen atoms, hydrated electrons, hydrogen peroxide, hydroxyl radicals and their byproducts. The determination methods for hydroxyl radicals are potentially applicable as a chemical dosimeter for determining the intensity of ionizing radiation.…”

Photoformation of OH radical in water-extract of atmospheric aerosols and aqueous solution of water-soluble gases collected in Higashi-Hiroshima, Japan

“…Therefore, the photo-Fenton reaction may occur if atmospheric watersoluble gases meet with iron species in the aqueous phase. To identify the formation potential of •OH in the atmospheric aqueous phase, a known amount (excess) of iron (III) was added into the solution of the WSG fraction and the R OH of the photo-Fenton reaction was then determined using the method described by Nakatani et al (2007). One µM potassium trioxalate ferrate (III) with 0.5 µM H 2 O 2 is added to the solution of the WSG fraction.…”

“…Even though studies of •OH photoformation in cloud droplets, fog, dew and rain have been conducted Arakaki and Faust, 1998, Anastasio et al, 1994Nakatani et al, 2007), only a few studies have investigated the water-extract of atmospheric aerosols (Arakaki et al, 2006, Kondo et al, 2009; therefore, sources and sinks of •OH have not been clarified.…”