Heterogeneous atmospheric reactivity of pesticides currently used in viticulture
International audience
Heterogeneous atmospheric ozonolysis of currently used pesticides in Viticulture
Currently used pesticides are semi-volatile organic compounds and often found in the particulate phase. In fact, all European regulations account for the reactivity of pesticides with OH radicals in the gaseous phase, this approximation might significantly underestimate their lifetimes. In our study, we determined the atmospheric half-lives towards...
Influence of pesticide mixture on their heterogeneous atmospheric degradation by ozone and OH radicals
Pesticides in the atmosphere can exist in both gaseous and particulate phases due to their semi-volatile properties. They can undergo degradation when exposed to atmospheric oxidants like ozone and hydroxyl radicals. The majority of studies on the atmospheric reactivity of pesticides study them in combination, without considering potential mixture ...
Photolytic degradation of commonly used pesticides adsorbed on silica particles
The currently used pesticides are mostly semi-volatile organic compounds. As a result, a fraction of them can be adsorbed on atmospheric aerosol surface. Their atmospheric photolysis is poorly documented, and gaps persist in understanding their reactivity in the particle phase. Laboratory experiments were conducted to determine the photolysis rates...
Heterogeneous atmospheric degradation of pesticides by ozone: Influence of relative humidity and particle type
In the atmosphere pesticides can be adsorbed on the surface of particles, depending on their physico-chemical properties. They can react with atmospheric oxidants such as ozone but parameters influencing the degradation kinetics are not clear enough. In this study the heterogeneous ozonolysis of eight commonly used pesticides (i.e., difenoconazole,...
Physics and chemistry on the surface of interstellar dust grains : the effect of O-atom diffusion and chemical desorptio...
The interstellar medium is the matter that exists in the space between the star systems in a galaxy. It is composed of gas and elongated tiny dust grains. To date, plenty of molecules (> 170) are known to exist in the interstellar medium. The presence of most of them can be understood in terms of gas phase reactions but the synthesis of some key sp...
Time-dependent uptake of NO3 by sea salt
Published in Journal of Atmospheric Chemistry
Using a coated-insert flow tube reactor coupled to a low-energy electron-impact mass spectrometer with molecular beam sampling, we studied uptake of NO3 by sea salt at room temperature and [NO3] = 8⋅1011 − 4⋅1013 molecule cm−3. The radical uptake coefficient γ(t) is time dependent: its initial value (γini) decreases exponentially with the character...
Kinetics of the reactions of soot surface-bound polycyclic aromatic hydrocarbons with NO2
Published in Journal of Atmospheric Chemistry
The kinetics of heterogeneous reactions of NO2 with 17 polycyclic aromatic hydrocarbons (PAHs) adsorbed on laboratory generated kerosene soot surface was studied over the temperature range (255–330) K in a low pressure flow reactor combined with an electron-impact mass spectrometer. The kinetics of soot-bound PAH consumption due to their desorption...
