HAL-INERIS
Not a member yet
8807 research outputs found
Sort by
Etude de la faisabilité technique du phytomanagement d'un site agricole pollué par les éléments potentiellement toxiques à l'aide de plantes à parfums aromatiques et médicinales (projet PhytEO)
No full textInternational audienc
Dissolution naturelle du gypse dans le sous-sol. Analyse et gestion des aléas mouvements de terrains de type affaissement et effondrement. Elaboration d'un guide
No full textInternational audienc
Major Influence of Secondary Organic Aerosols on Black Carbon Absorption Enhancement in the Region of Paris, France
No full textInternational audienceAtmospheric black carbon (BC) and light-absorbing organic aerosol (also referred as brown carbon, BrC) have strong effects on the Earth’s climate by absorbing direct solar radiation. To better characterize and quantify these effects, it is still needed to improve the understanding of specific underlying mechanisms such as the influence of primary emissions and secondary processes on absorption properties over long-term periods. We report here results of a three-year continuous field observations of both optical and chemical aerosol properties from March 2014 to March 2017 at a suburban background station (SIRTA) in the Paris region (France). Submicron non-refractory aerosol species were measured in near real-time using an aerodyne aerosol chemical speciation monitor and were apportioned using Positive Matrix Factorization (PMF) analysis to identify and quantified major organic aerosol (OA) sources. Light absorption properties of BC and BrC were determined by direct measurements using a 7-wavelength aethalometer equipped with the dual spot technology. Co-located 24-hy filter-based analyses were performed by thermo-optical technique to quantify the mass concentration of elemental carbon (EC) in PM2.5. Absorption enhancement (Eabs) of BC-containing particles was obtained using mass absorption coefficient (MAC) ratios calculated between observed (= babs / [EC]) and expected values for uncoated BC. Results showed important BrC contribution to the total absorption in the near UV during te winter season, that could be attributed to residential wood burning activities. Even more interestingly, the observed Eabs significantly increased with the mass ratio of secondary aerosols to EC, suggesting a strong influence of this secondary components on BC absorption enhancement. This was further associated with the production of highly oxidized secondary organic aerosols (SOA), especially at summertime. These findings infer that considering the yearly cycle of photochemical SOA production should help better assessing seasonal influences of BC global warming. They also suggest that efficient strategies for the reduction of SOA burden in the atmosphere - including abatement of volatile organic compounds emissions - could significantly weaken the BC radiative forcing, at least over the Paris area
Intercomparison of AMS and ACSM Measurements for Particulate Organic Nitrates (pON)
No full textInternational audienceParticulate organic nitrates (pON) are important atmospheric species that are formed through the reactions of volatile organic compounds (VOCs) with atmospheric oxidants (OH/NO3 radicals) and NOx. They may account for a considerable fraction of fine particulate matter (PM2.5) but their concentrations, sources and formation processes remain nearly unexplored aspects of atmospheric chemistry. Recently, a methodology based on time-of-flight aerosol mass spectrometer (ToF-AMS) measurements of NO+ and NO2+ fragments of nitrate aerosol has been proposed to distinguish between inorganic nitrates and pON. However, this methodology has not been applied to quadrupole or time-of-flight Aerosol Chemical Speciation Monitors (Q-ACSM/ToF-ACSM) or to anthropogenic pON. In the present study, the response of 8 different ACSM, and 1 Long-ToF-AMS, instruments to pON was explored through a unique experimental setup under controlled conditions at the Aerosol Chemical Monitor Calibration Centre (ACMCC). pON were generated in a Potential Aerosol Mass (PAM) oxidation flow reactor from the reaction of NO3 radical with single VOC precursors, two biogenic (limonene and b-pinene) and two anthropogenic (acenaphthylene and guaiacol). The results of this intercomparison will be presented, with a focus on variations in the mass spectra of pON (NO+/NO2+, organics fragments and organic-to-nitrate ratios) as a function of: (1) instrumental configuration (AMS vs ACSM, Q-ACSM vs ToF-ACSM, standard vs capture vaporizers) (2) pON precursor (3) particle size and (4) particle mass concentration. Possible improvements of the default fragmentation table used to calculate the contributions to the signal for organic and nitrates will be proposed in order to account for interfering signals from other species. The impact of the observed variabilities on the NO+/NO2+ methodology will also be investigated
High resolution mass spectrometry-based non-target screening can support regulatory environmental monitoring and chemicals management
No full textInternational audienceNon-target screening (NTS) including suspect screening with high resolution mass spectrometry has already shown its feasibility in detecting and identifying emerging contaminants, which subsequently triggered exposure mitigating measures. NTS has a large potential for tasks such as effective evaluation of regulations for safe marketing of substances and products, prioritization of substances for monitoring programmes and assessment of environmental quality. To achieve this, a further development of NTS methodology is required, including: (i) harmonized protocols and quality requirements, (ii) infrastructures for efficient data management, data evaluation and data sharing and (iii) sufficient resources and appropriately trained personnel in the research and regulatory communities in Europe. Recommendations for achieving these three requirements are outlined in the following discussion paper. In particular, in order to facilitate compound identification it is recommended that the relevant information for interpretation of mass spectra, as well as about the compounds usage and production tonnages, should be made accessible to the scientific community (via open-access databases). For many purposes, NTS should be implemented in combination with effect-based methods to focus on toxic chemicals
Ignition temperatures of dust layers and bulk storages in hot environments
No full textInternational audienc
What can we expect from data assimilation for air quality forecast? 1: Quantification with academic test cases
No full textInternational audienceData assimilation is successfully used for meteorology since many years and is now more and more used for atmospheric composition issues (air quality analysis and forecast). The data assimilation of pollutants remains difficult and its deployment is currently in progress. It is thus difficult to have a quantitative knowledge of what we can expect as maximum of benefit. In this study, we propose a simple framework to make this quantification. In this first part, the gain of data assimilation is quantified using academic but realistic test cases over an urbanized polluted area and during a summertime period favourable to ozone formation. Different data assimilation configurations are tested, corresponding to different amount of data available for assimilation. For ozone (O 3) and nitrogen dioxide (NO 2), it is shown that the benefit due to data assimilation lasts from a few hours to a maximum possible of 60 and 21 hours, respectively. Maps of the number of hours are presented, spatializing the benefit of data assimilation
UNREAL Project: Unveiling nucleation mechanism in aircraft engine exhaust and its link with fuel composition
No full textInternational audienceWe present UNREAL project, funded by the french research agency. The main objectives of this project are:1) To determine the mechanism behind vPM formation in the engine exhaust and if there is a link with fuel composition2) To establish a sampling protocol for vPM measurements that can be used in certification processes3) To determine the impact of fuel chemical composition on the physico-chemical properties of vPM and nvP
Mettre en sécurité les cavités souterraines
No full textInternational audienceOutre leurs nombreuses responsabilités en matière de prévention du risque associé aux cavités souterraines abandonnées, les collectivités peuvent dans certains cas avoir la charge de travaux de mise en sécurité. Se pose alors la question du choix des techniques de confortement..