A5105457154- Atmospheric chemistry and aerosols
- High-Temperature Coating Behaviors
- Atmospheric Ozone and Climate
- Nuclear Materials and Properties
- Air Quality Monitoring and Forecasting
- Air Quality and Health Impacts
- Planetary Science and Exploration
- Metallurgical Processes and Thermodynamics
- Space Exploration and Technology
- Catalytic Processes in Materials Science
- Metal and Thin Film Mechanics
- Astro and Planetary Science
- Semiconductor materials and devices
- Advanced materials and composites
- Spectroscopy and Laser Applications
- Atmospheric and Environmental Gas Dynamics
- High Temperature Alloys and Creep
- Atmospheric aerosols and clouds
- Indoor Air Quality and Microbial Exposure
- Advanced ceramic materials synthesis
- Oil Spill Detection and Mitigation
- Odor and Emission Control Technologies
- Marine and coastal ecosystems
- Metal Alloys Wear and Properties
- Scientific Research and Discoveries
Université Claude Bernard Lyon 1
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Institut de Recherches sur la Catalyse et l'Environnement de Lyon
2016-2025
University of Warwick
2016-2025
Institut Pascal
2002-2024
Total (France)
2011-2024
Catalytic Materials (United States)
2015-2023
Monash University
2023
Centre de Gestion Scientifique
2023
Université Clermont Auvergne
1999-2021
There is now much evidence that OH radicals and H2O2 are spontaneously generated at the air–water interface of atmospheric aerosols. Here, we investigated effect halide anions (Cl–, Br–, I–), which abundant in marine aerosols, on this production. Droplets were via nebulization water solutions containing Na2SO4, NaCl, NaBr, NaI solutions, was monitored as a function salt concentration under relevant conditions. The interfacial radical formation also by adding terephthalic acid (TA) to our...
Abstract. A new simulation chamber has been built at the Interuniversitary Laboratory of Atmospheric Systems (LISA). The CESAM (French acronym for Experimental Multiphasic Simulation Chamber) is designed to allow research in multiphase atmospheric (photo-) chemistry which involves both gas phase and condensed processes including aerosol cloud chemistry. potential carry out variable temperature pressure experiments under a very realistic artificial solar irradiation. It consists 4.2 m3...
Abstract. Nitrous acid measurements were carried out during the MEGAPOLI summer and winter field campaigns at SIRTA observatory in Paris surroundings. Highly variable HONO levels observed campaigns, ranging from 10 ppt to 500 1.7 ppb winter. Significant mixing ratios have also been measured daytime hours, comprised between some tenth of 200 for campaign few 1 campaign. Ancillary measurements, such as NOx, O3, photolysis frequencies, meteorological parameters (pressure, temperature, relative...
Abstract. Chemical Ionisation Mass Spectrometer measurements of hydroxyl radical (OH) and the sum hydroperoxy organic peroxy (HO2+RO2) radicals were conducted during MEGAPOLI summer field campaign at SIRTA observatory near Paris, France, in July 2009. OH showed a typical diurnal variation with averaged daytime maxima values around 5×106 1.2×108 molecule cm−3, respectively. Simultaneously, large number ancillary measurements, such as NOx, O3, HONO, HCHO other VOCs also conducted. These data...
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,...
Abstract. Measurements of gaseous and particulate organic carbon were performed during the MEGAPOLI experiments, in July 2009 January–February 2010, at SIRTA observatory suburban Paris. comprise primary secondary volatile compounds (VOCs), both anthropogenic biogenic origins, including C12–C16 n-alkanes intermediate volatility (IVOCs), suspected to be efficient precursors aerosol (SOA). The time series are generally consistent with times regional scale, clearly affected by meteorology air...
Abstract The heterogeneous reaction between SO 2 and unsaturated compounds results in the efficient production of organosulfates for several fatty acids long‐chain alkenes. presence an acid group, physical state reactants (solid or liquid), nature double bond ( cis , trans terminal), use light irradiation all have impact on rate. was investigated using different set‐ups (coated flow tube, aerosol diffuse reflectance infrared Fourier transform cell). products were identified by...
Atmospheric aerosol particles may contain light absorbing (brown carbon, BrC), triplet forming organic compounds that can sustain catalytic radical reactions and thus contribute to oxidative aging. We quantify UVA induced production initiated by imidazole-2-carboxaldehyde (IC), benzophenone (BPh). 4-benzoylbenzoic acid (BBA) in the presence of nonabsorbing organics citric (CA), shikimic (SA), syringol (Syr) at varying mixing ratios. observed a maximum HO2 release 1013 molecules min–1 cm–2...
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...
Interfaces are ubiquitous in the environment and many atmospheric key processes, such as gas deposition, aerosol, cloud formation are, at one stage or another, strongly impacted by physical chemical processes occurring interfaces. Here, photoinduced chemistry of an air/water interface coated with nonanoic acid—a fatty acid surfactant we use a proxy for chemically complex natural aqueous surface microlayers—was investigated source volatile semivolatile reactive organic species. The carboxylic...
Nitrate anion (NO3–) is ubiquitous in the environment, and its photochemistry produces nitrous acid (HONO), a major source of tropospheric hydroxyl radical (OH). Enhanced HONO(g) emissions have been observed from NO3–(aq) photolysis field studies, although underlying reasons for this enhancement are debated. Here, we show that part caused by changes secondary nitrate due to dissolved aliphatic organic matter (DAOM). Increased yields superoxide (O2–) HONO were when NO3– solutions (pH 6)...
Films of biogenic compounds exposed to the atmosphere are ubiquitously found on surfaces cloud droplets, aerosol particles, buildings, plants, soils and ocean. These air/water interfaces host countless amphiphilic concentrated there with respect in bulk water, leading a unique chemical environment. Here, photochemical processes at interface biofilm-containing solutions were studied, demonstrating abiotic VOC production from authentic surfactants under ambient conditions. Using combination...
Organic interfaces that exist at the sea surface microlayer or as surfactant coatings on cloud droplets are highly concentrated and chemically distinct from underlying bulk overlying gas phase. Therefore, they may be potentially unique locations for chemical photochemical reactions. Recently, production of volatile organic compounds (VOCs) was reported a nonanoic acid interface however, subsequent secondary aerosol (SOA) particle incapable being observed. We investigated SOA formation due to...
While acknowledged as key components in the formation of new particles atmosphere, accurate characterization gaseous (highly) oxygenated organic compounds remains challenging and requires analytical developments. Earlier studies have successfully used nitrate ion (NO3–) based chemical ionization (CI) coupled to atmospheric pressure interface time-of-flight mass spectrometry (CI-APi-TOF) for monitoring these compounds. Despite many breakthroughs recent years, CI-APi-TOF has limitations,...
Chemical ionization Orbitrap mass spectrometry (CI-Orbitrap) represents a promising new technique for gas-phase analysis in analytical and atmospheric chemistry mainly due to its very high resolving power. In this work, we performed the first side-by-side comparison between CI-Orbitrap widely used pressure interface time-of-flight (CI-APi-TOF) using two different chemical methods, i.e., acetate-ion-based (CH3COO-) aminium-ion-based (n-C3H7NH3+) schemes. The capability of at accurately...
Photodegradation alters secondary organic aerosol (SOA) chemical composition and physical properties, promoting the formation of oxidation products in both gas- particle-phase by depleting high-molecular-weights species within SOA.
While biomass burning (BB) is the largest source of fine particles in atmosphere, influence relative humidity (RH) and photochemistry on BB secondary organic aerosol (BB-SOA) formation aging remains poorly constrained. These effects need to be addressed better capture comprehend evolution BB-SOA atmosphere. Cresol (C7H8O) used as a proxy investigate these effects. It emitted directly from has been identified significant SOA precursor residential wood-burning emissions. The gas-...
Abstract. Organic aerosols (OA) play a critical role in the atmosphere by directly altering human health and climate. Understanding their formation evolution as well physicochemical properties requires detailed characterization of chemical composition. Despite advanced analytical techniques developed within last decades, real-time online measurement atmospheric particles remains challenging suffers from different artifacts. In this work, we introduce newly designed wall-free particle...
Polymer‐conjugated peptides are attractive building blocks for the construction of new nanomaterials. However, ability to control self‐assembly these materials remains a major limitation their wider utilization. Herein, we report facile strategy fine‐tune assembly water‐soluble hydrophilic polymer‐conjugated cyclic by incorporating defined, short hydrocarbon linker between polymer and peptide. This addition creates well‐defined hydrophobic ‘inner shell’ that suppresses water from disrupting...
Polymer‐conjugated peptides are attractive building blocks for the construction of new nanomaterials. However, ability to control self‐assembly these materials remains a major limitation their wider utilization. Herein, we report facile strategy fine‐tune assembly water‐soluble hydrophilic polymer‐conjugated cyclic by incorporating defined, short hydrocarbon linker between polymer and peptide. This addition creates well‐defined hydrophobic ‘inner shell’ that suppresses water from disrupting...