Peroxy radicals, when generated in the presence of hindered-amine light stabilizers (HALS), oxidized HALS to produce nitroxides. This reaction, in addition to the scavenging of alkyl radicals by nitroxides, forms a cycle describing HALS as a class of excellent polymer stabilizers. As model systems for the mechanism of the oxidation of HALS, both alkyl peroxy and acyl peroxy radicals were produc...

Secondary organic aerosol (SOA) formation from the photooxidation of m-xylene, toluene, and benzene is investigated in the Caltech environmental chambers. Experiments are performed under two limiting NOx conditions; under high-NOx conditions the peroxy radicals (RO2) react only with NO, while under low-NOx conditions they react only with HO2. For all three aromatics studied (m-xylene, toluene, ...

In a green alga, Haematococcus pluvialis, a morphological change of vegetative cells into cyst cells was rapidly induced by the addition of acetate or acetate plus Fe to the vegetative growth phase. Accompanied by cyst formation, algal astaxanthin formation was more enhanced by the addition of acetate plus Fe than by the addition of acetate alone. Encystment and enhanced carotenoid biosynthesis...

BACKGROUND Cutting edge technologies based on Advanced Oxidation Processes (AOP) are under development for the elimination of highly persistent organic molecules (like pesticides) from water matrices. Among them, ionizing radiation treatment represents a promising technology that requires no additives and can be easily adapted to an industrial scale. In these processes several reactive species ...

First generation product yields from the OH-initiated oxidation of methyl vinyl ketone (3-buten-2-one, MVK) under both low and high NO conditions are reported. In the low NO chemistry, three distinct reaction channels are identified leading to the formation of (1) OH, glycolaldehyde, and acetyl peroxy R2a , (2) a hydroperoxide R2b , and (3) an α-diketone R2c . The α-diketone likely results from...

The self-reaction of the ethyl peroxy radical (C2H5O2) (1) has been studied using laser photolysis coupled to a selective time-resolved detection two different radicals by continuous-wave cavity ring-down spectroscopy (cw-CRDS) in near-infrared range: C2H5O2 was detected Ã-X̃ electronic transition at 7596 cm–1 and HO2 2ν1 vibrational overtone 6638.2 cm–1. Radicals were generated from pulsed 351 ...