81 research outputs found
Ionic Strength Effect Alters the Heterogeneous Ozone Oxidation of Methoxyphenols in Going from Cloud Droplets to Aerosol Deliquescent Particles
Validation of an experimental setup to study atmospheric heterogeneous ozonolysis of semi-volatile organic compounds
International audienceThere is currently a need for reliable experimental procedures to follow the heterogeneous processing simulating the atmospheric conditions. This work offers an alternative experimental device to study the behaviour of semi-volatile organic compounds (SVOC) that presumably exhibit extremely slow reactivity (e.g. pesticides) towards the atmospheric oxidants such as ozone and OH. Naphthalene was chosen as a test compound since it was widely studied in the past and hence represents a good reference. Prior to ozone exposure, the gaseous naphthalene was adsorbed via gas-solid equilibrium on silica and XAD-4 particles. Then, the heterogeneous reaction of ozone with adsorbed naphthalene was investigated in specially designed flow tube reactors. After the reaction, the remaining naphthalene (adsorbed on particles surface) was extracted, filtered and analyzed by Gas Chromatography-Flame Ionization Detector (GC-FID). Thus, the kinetics results were obtained following the consumption of naphthalene. Using this procedure, the rate constants of heterogeneous ozonolysis of naphthalene (kO3 silica=2.26 (±0.09)×10−17 cm3 molec−1 s−1 and kO3 XAD-4=4.29 (±1.06)×10−19 cm3 molec−1 s−1) were determined for silica and XAD-4 particles, at 25°C and relative humidity <0.7%. The results show that the nature of the particles significantly affects the kinetics and that heterogeneous ozonolysis of naphthalene is faster than its homogeneous ozonolysis in the gas phase
Effect of inorganic salts on N'containing organic compounds formed by heterogeneous reaction of NO2 with oleic acid
Tracking photodegradation products and bond-cleavage reaction pathways of triclosan using ultra-high resolution mass spectrometry and stable carbon isotope analysis
Ionic Strength Effect on Photochemistry of Fluorene and Dimethylsulfoxide at the Air-Sea Interface: Alternative Formation Pathway of Organic Sulfur Compounds in a Marine Atmosphere
Simultaneous measurement of nitrous acid, nitric acid, and nitrogen dioxide by means of a novel multipollutant diffusive sampler in libraries and archives
In Situ Mass Spectrometric Detection of Interfacial Intermediates in the Oxidation of RCOOH(aq) by Gas-Phase OH-Radicals
Influence of Combustion Conditions on Hydrophilic Properties and Microstructure of Flame Soot
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