Investigating the gas-phase reaction mechanism of catechol with ozone: Product analysis and insights.

Volatile aromatic compounds (VOCs) are ubiquitous in the environment, they can be emitted from biogenic and anthropogenic sources. They can contribute to the formation of many products leading to the formation of secondary organic aerosols (SOA). The products of the gas phase reaction of 1,2-benzenediol (catechol) with ozone were studied in a simulation chamber at atmospheric pressure and 294 ± 2 K in presence of different levels of relative humidity (0-60%).

Contributions of local and regional anthropogenic sources of metals in PM at an urban site in northern France.

PM have been related to various adverse health effects, mainly due to their ability to penetrate deeply and to convey harmful chemical components, such as metals inside the body. In this work, PM were sampled at Saint-Omer, a medium-sized city located in northern France, in March-April 2011 and analyzed for their total carbon, water-soluble ions, major and trace elements. More specifically, the origin of 15 selected elements was examined using different tools including enrichment factors, conditional bivariate probability function (CBPF) representations, diagnostic ratios and receptor modelling.

Kinetic Study of the Gas-Phase Reactions of Nitrate Radicals with Methoxyphenol Compounds: Experimental and Theoretical Approaches.

The gas-phase reactions of five methoxyphenols (three disubstituted and two trisubstituted) with nitrate radicals were studied in an 8000 L atmospheric simulation chamber at atmospheric pressure and 294 ± 2 K. The NO3 rate constants were investigated with the relative kinetic method using PTR-ToF-MS and GC-FID to measure the concentrations of the organic compounds. The rate constants (in units of cm(3) molecule(-1) s(-1)) determined were: 2-methoxyphenol (guaiacol; 2-MP), k(2-MP) = (2.

Reaction Kinetics of Catechol (1,2-Benzenediol) and Guaiacol (2-Methoxyphenol) with Ozone.

The kinetic reactions of 1,2-benzenediol (catechol) and 2-methoxyphenol (guaiacol) with ozone were studied in a simulation chamber (8 m(3)) under dark conditions. The rate coefficients were measured at 294 ± 2 K, atmospheric pressure and dry conditions (relative humidity, RH < 1%), except for 1,2-benzenediol where they were also measured as a function of relative humidity (RH = 1-80%). The concentrations of organic compounds were followed by a PTR-ToF-MS for a continuous monitoring of gas-phase species.

Heterogeneous interaction of H2O2 with Arizona Test Dust.

The heterogeneous interaction of H2O2 with solid films of Arizona Test Dust (ATD) was investigated under dark conditions and in presence of UV light using a low pressure flow tube reactor coupled with a quadrupole mass spectrometer. The uptake coefficients were measured as a function of the initial concentration of gaseous H2O2 ([H2O2]0 = (0.18 - 5.

Kinetics and products of heterogeneous reaction of HONO with Fe2O3 and Arizona Test Dust.

Kinetics and products of the reaction of HONO with solid films of Fe2O3 and Arizona Test Dust (ATD) were investigated using a low pressure flow reactor (1 - 10 Torr) combined with a modulated molecular beam mass spectrometer. The reactive uptake of HONO was studied as a function of HONO concentration ([HONO]0 = (0.6 - 15.

Interaction of OH radicals with Arizona Test Dust: uptake and products.

Kinetics and products of the interaction of OH radicals with solid films of Arizona Test Dust (ATD) were studied using a low pressure flow reactor (0.5-3 Torr) combined with a modulated molecular beam mass spectrometer for monitoring of the gaseous species involved. The reactive uptake coefficient of OH was measured from the kinetics of OH consumption on Pyrex rods coated with ATD as a function of OH concentration ((0.

Heterogeneous interaction of H2O2 with TiO2 surface under dark and UV light irradiation conditions.

The heterogeneous interaction of H(2)O(2) with TiO(2) surface was investigated under dark conditions and in the presence of UV light using a low pressure flow tube reactor coupled with a quadrupole mass spectrometer. The uptake coefficients were measured as a function of the initial concentration of gaseous H(2)O(2) ([H(2)O(2)](0) = (0.17-120) × 10(12) molecules cm(-3)), irradiance intensity (J(NO(2)) = 0.

Reactive uptake of HONO to TiO2 surface: "dark" reaction.

The interaction of HONO with TiO(2) solid films was studied under dark conditions using a low pressure flow reactor (1-10 Torr) combined with a modulated molecular beam mass spectrometer for monitoring of the gaseous species involved. The reactive uptake of HONO to TiO(2) was studied as a function of HONO concentration ([HONO)(0) = (0.3-3.

Interaction of NO2 with TiO2 surface under UV irradiation: products study.

The interaction of NO(2) with TiO(2) solid films was studied under UV irradiation using a low pressure flow reactor (1-10 Torr) combined with a modulated molecular beam mass spectrometer for monitoring of the gaseous species involved. HONO, NO, and N(2)O were observed as the products of the reactive uptake of NO(2) to the illuminated TiO(2) surface with the sum of their yields corresponding nearly to 100% of the nitrogen mass balance. The yield of the products was measured as a function of different parameters such as irradiance intensity, relative humidity (RH), temperature, and concentrations of NO(2) and O(2).