A5055594784- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Atmospheric aerosols and clouds
- Catalytic Processes in Materials Science
- Spectroscopy and Laser Applications
- Indoor Air Quality and Microbial Exposure
- Advanced Chemical Sensor Technologies
- Metabolomics and Mass Spectrometry Studies
- Atmospheric and Environmental Gas Dynamics
- Odor and Emission Control Technologies
- Water Quality Monitoring and Analysis
- Vehicle emissions and performance
- Toxic Organic Pollutants Impact
- Mass Spectrometry Techniques and Applications
- Analytical chemistry methods development
- Chemical Reactions and Mechanisms
- Geophysics and Gravity Measurements
- Inorganic and Organometallic Chemistry
- Electron Spin Resonance Studies
- Chemical Reactions and Isotopes
- Cyclone Separators and Fluid Dynamics
- Marine and coastal ecosystems
- Dye analysis and toxicity
Institut de Recherches sur la Catalyse et l'Environnement de Lyon
2018-2025
Centre National de la Recherche Scientifique
2015-2025
Université Claude Bernard Lyon 1
2018-2025
Tofwerk (Switzerland)
2023-2024
University of Helsinki
2016-2021
Catalytic Materials (United States)
2019-2021
Forum Réfugiés - Cosi
2021
University of North Carolina at Chapel Hill
2014-2020
University of Minnesota
2019
Helsinki Institute of Physics
2016-2017
Abstract. The impact of aerosols on climate and air quality remains poorly understood due to multiple factors. One the current limitations is incomplete understanding contribution oxygenated products, generated from gas-phase oxidation volatile organic compounds (VOCs), aerosol formation. Indeed, atmospheric gaseous chemical processes yield thousands (highly) species, spanning a wide range formulas, functional groups and, consequently, volatilities. While recent mass spectrometric...
Abstract New particle formation in the Arctic atmosphere is an important source of aerosol particles. Understanding processes secondary crucial due to their significant impact on cloud properties and therefore amplification. We observed molecular new particles from low‐volatility vapors at two sites with differing surroundings. In Svalbard, sulfuric acid (SA) methane sulfonic (MSA) contribute some extent condensation nuclei (CCN). This occurs via ion‐induced nucleation SA NH 3 subsequent...
Abstract. Substantial amounts of secondary organic aerosol (SOA) can be formed from isoprene epoxydiols (IEPOX), which are oxidation products mainly under low-NO conditions. Total IEPOX-SOA, may include SOA other parallel pathways, was quantified by applying positive matrix factorization (PMF) to mass spectrometer (AMS) measurements. The IEPOX-SOA fractions (OA) in multiple field studies across several continents summarized here and show consistent patterns with the concentration gas-phase...
In the present study, formation of aromatic organosulfates (OSs) from photo-oxidation polycyclic hydrocarbons (PAHs) was investigated. Naphthalene (NAP) and 2-methylnaphthalene (2-MeNAP), two most abundant gas-phase PAHs thought to represent "missing" sources urban SOA, were photochemically oxidized in an outdoor smog chamber facility presence nonacidified acidified sulfate seed aerosol. Effects aerosol composition, acidity relative humidity on OS examined. Chemical characterization SOA...
Secondary organic aerosol (SOA) produced from reactive uptake and multiphase chemistry of isoprene epoxydiols (IEPOX) has been found to contribute substantially (upward 33%) the fine mass over Southeastern U.S. Brown carbon (BrC) in rural areas this region linked secondary sources summer when influence biomass burning is low. We demonstrate formation light-absorbing (290 < λ 700 nm) SOA constituents trans-β-IEPOX onto preexisting sulfate aerosols as a potential source BrC. IEPOX-derived BrC...
Acid-driven multiphase chemistry of isoprene epoxydiols (IEPOX), key oxidation products, with inorganic sulfate aerosol yields substantial amounts secondary organic (SOA) through the formation organosulfur compounds. The extent and implications inorganic-to-organic conversion, however, are unknown. In this article, we demonstrate that extensive consumption occurs, which increases IEPOX-to-inorganic concentration ratio (IEPOX/Sulfinorg), as determined by laboratory measurements....
Atmospheric oxidation of isoprene under low-NOx conditions leads to the formation hydroxyhydroperoxides (ISOPOOH). Subsequent ISOPOOH largely produces epoxydiols (IEPOX), which are known secondary organic aerosol (SOA) precursors. Although SOA from IEPOX has been previously examined, systematic studies characterization through a non-IEPOX route 1,2-ISOPOOH lacking. In present work, authentic was systematically examined with varying compositions and relative humidity. High yields highly...
Abstract. We report the formation of aliphatic organosulfates (OSs) in secondary organic aerosol (SOA) from photooxidation C10–C12 alkanes. The results complement those our laboratories reporting OSs and sulfonates gas-phase oxidation polycyclic aromatic hydrocarbons (PAHs). Both studies strongly support anthropogenic precursors, as hypothesized on basis recent field which were detected fine collected several major urban locations. In this study, dodecane, cyclodecane decalin, considered to...
In the southeastern US, substantial emissions of isoprene from deciduous trees undergo atmospheric oxidation to form secondary organic aerosol (SOA) that contributes fine particulate matter (PM2.5). Laboratory studies have revealed anthropogenic pollutants, such as sulfur dioxide (SO2), oxides nitrogen (NO x ), and acidity, can enhance SOA formation hydroxyl radical (OH)-initiated isoprene; however, mechanisms by which specific pollutants in ambient PM2.5 remain unclear. As one aspect an...
Isoprene-derived secondary organic aerosol (SOA) is mainly formed through acid-catalyzed reactive uptake of isoprene-derived epoxydiols (IEPOX) onto sulfate particles. The effect IEPOX-derived SOA on the physicochemical properties existing aerosols and resulting capacity for further formation remains unclear. This study systematically examined influences phase state, morphology, acidity pre-existing particles, as well their implications reactivity evolution these By combining thermodynamic...
Light-absorbing brown carbon (BrC) constituents of organic aerosol (OA) have been shown to significantly absorb ultraviolet (UV) and visible light thus impact radiative forcing. However, molecular identification the BrC is still limited. In this study, we characterize at level in (i) aerosols emitted by combustion peat, fern/leaf, charcoal from Indonesia (ii) ambient collected Singapore during 2015 haze episode. Aerosols were analyzed using ultra performance liquid chromatography instrument...
Northern China is regularly subjected to intense wintertime "haze events", with high levels of fine particles that threaten millions inhabitants. While sulfate a known major component these haze particles, its formation mechanism remains unclear especially under highly polluted conditions, state-of-the-art air quality models unable reproduce or predict field observations. These conditions are generally characterized by simultaneous emissions SO2 and photosensitizing materials. In this study,...
Exchange of atmospheric organic compounds between gas and particle phases is important in the production chemistry particle-phase mass but poorly understood due to a lack simultaneous measurements both individual compounds. Measurements particle- gas-phase are reported here for southeastern United States central Amazonia. Polyols formed from isoprene oxidation contribute 8% 15% on average at these sites also observed have substantial concentrations contrary many models that treat as...
Nighttime oxidation of biogenic volatile organic compounds (BVOCs) by nitrate radicals (NO3·) represents one the most important interactions between anthropogenic and natural emissions, leading to substantial secondary aerosol (SOA) formation. The direct climatic effect such SOA cannot be quantified because its optical properties atmospheric fate are poorly understood. In this study, we generated from NO3· a series BVOCs including isoprene, monoterpenes, sesquiterpenes. were subjected...
Abstract. In order to investigate the negative ions in boreal forest we have performed measurements chemically characterise composition of negatively charged clusters containing highly oxygenated molecules (HOMs). Additionally, compared this information with chemical neutral gas-phase detected ambient atmosphere during same period. The was retrieved using an atmospheric pressure interface time-of-flight mass spectrometer (APi-TOF-MS) while (mainly sulfuric acid and HOMs) were characterised...
Abstract. Secondary organic aerosol (SOA) forms a major part of the tropospheric submicron aerosol. Still, exact formation mechanisms SOA have remained elusive. Recently, newly discovered group oxidation products volatile compounds (VOCs), highly oxygenated molecules (HOMs), been proposed to be responsible for large fraction formation. To assess potential HOMs form and even take in new particle formation, knowledge their volatilities is essential. However, due exotic, partially unknown,...
Aqueous methylglyoxal chemistry has often been implicated as an important source of oligomers in atmospheric aerosol. Here we report on chemical analysis brown carbon aerosol particles collected from cloud cycling/photolysis chamber experiments, where gaseous and methylamine interacted with glycine, ammonium, or methylammonium sulfate seed particles. Eighteen N-containing were identified the particulate phase by liquid chromatography/diode array detection/electrospray ionization...
Abstract. The capabilities of the recently developed Vocus proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF) are reported for first time based on ambient measurements. With deployment PTR-TOF, we present an overview observed gas-phase (oxygenated) molecules in French Landes forest during summertime 2018 and gain insights into atmospheric oxidation terpenes, which emitted large quantities atmosphere play important roles secondary organic aerosol production. Due to greatly...
Abstract Organic peroxy radicals (RO 2 ) play a pivotal role in the degradation of hydrocarbons. The autoxidation atmospheric RO produces highly oxygenated organic molecules (HOMs), including low-volatility ROOR dimers formed by bimolecular + reactions. HOMs can initiate and greatly contribute to formation growth particles. As result, have far-reaching health climate implications. Nevertheless, structures mechanism remain elusive. Here, we present in-situ characterization dimer structure...
Abstract. Atmospheric organic vapors play essential roles in the formation of secondary aerosol. Source identification these is thus fundamental to understanding their emission sources and chemical evolution atmosphere further impact on air quality climate change. In this study, a Vocus proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF) was deployed two forested environments, Landes forest southern France boreal Finland, measure atmospheric vapors, including both volatile...
The mechanistic pathway by which high relative humidity (RH) affects gas–particle partitioning remains poorly understood, although many studies report increased secondary organic aerosol (SOA) yields at RH. Here, we use real-time, molecular measurements of both the gas and particle phase to provide a understanding effect RH on biogenic oxidized molecules (from α-pinene isoprene) low temperatures (243 263 K) CLOUD chamber CERN. We observe increases in SOA mass 45 85% with increasing from...