UFR de Physique

Propositions de stages en laboratoire -- M2

Les offres sont actualisées en mai. Par exemple, les offres de stages pour l'année universitaire 2015-2016 seront mises en place en mai 2015, les offres de stages pour l'année universitaire 2016-2017 seront mises en place pour en mai 2016, etc.

Chemical characterization of automobile soot particles and analogues by mass spectrometry after laser desorption and laser ionization

  • Option International « Atmospheric Environnement » du parcours Lumière-Matière
  • Laboratoire: Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM)
  • Responsable du stage: CARPENTIER Yvain (Yvain.Carpentier@univ-lille1.fr, 03 20 33 64 64)
  • Co-responsable(s): FOCSA Cristian - THERSSEN Eric
  • Mots clés: soot particles, laser diagnostics, mass spectrometry
  • Fiche complète en PDF : Fiche complète en PDF

The objective of this traineeship is to study the surface chemical composition of soot particles produced by automobile engines or analogues sampled in standard laboratory flames. The particles studied are representative of part of the aerosols emitted by automobile traffic. To determine their toxicity and their influence on the environment or the climate, it is essential to characterize the chemical species adsorbed on these particles because surface compounds are responsible in a large extent for their physical and chemical properties. The particles will be sampled by a microprobe in standard laboratory flames, diluted in an inert carrier gas, transferred and deposited on a cold substrate under vacuum or collected on substrates in a cylinder motor (Bosch, Germany). The chemical composition of the soot surface will be analyzed by mass spectrometry coupled with laser desorption and laser ionization (L2MS) to obtain the size distributions of different molecular families adsorbed even at trace-levels. Specific single or multiphoton ionization schemes (SPI in the UV vacuum or REMPI) will be used to study selectively the different classes of molecules. This characterization will be completed by secondary ion mass spectrometry (SIMS). The study should enable both to determine the influence of fuel on the surface chemical composition of soot particles and to discern, as part of measures to engines or vehicles, the different sources of particles (combustion, fuel additives, lubricating oil, mechanical wear ...). This traineeship fits in the Labex CaPPA (WP5 "Aerosols & Clouds") and the European project PEMS4Nano (H2020 program).