Dans le cadre du Programme Régional CLIMIBIO (Contrat de Plan Etat-Région « Hauts de France » 2015-2020 et FEDER), nous recrutons des personnels affectés dans les différents laboratoires ou équipes du projet.
LPCA - Postdoctoral (12 month) : Evolution of the physical and chemical properties of secondary organic aerosols during their aging in the atmosphere
Keywords: Atmospheric simulation chamber, volatile organic compounds oxidation, secondary organic aerosols, hygroscopic properties, radiative effect
Project: Atmospheric aerosols inﬂuence climate directly by altering the absorption and scattering of solar and terrestrial radiations and indirectly by changing cloud properties. One of the major uncertainties in estimating the aerosol radiative effect is associated with the contribution of secondary organic aerosols (SOAs). During their atmospheric lifetime, which ranges from 48 to 72h, their physical and chemical properties do not stay constant but rather evolve in response to local atmospheric conditions. For example, more oxidized, less volatile and more hygroscopic SOAs are typically observed in remote areas as a result of continuous aging in the atmosphere. Since SOA contains a wide variety of organic compounds, which vary in terms of their size, structure, functionality and oxidation state, the processes associated with SOA aging are very complex. Experiments will be performed in the new atmospheric simulation chamber of the LPCA (CHARME) to the study the evolution of SOA properties (chemical composition, size, hygroscopicity, radiative impact...) during their aging.
This project takes place in the framework of the regional program CLIMIBIO.
Qualifications: The candidate should have a PhD in atmospheric physical chemistry and a good expertise in the use of analytical techniques dedicated to the metrology of gases and particles in the atmosphere (GC-MS, PTR-MS, SMPS, optical techniques like IBBCEAS, CRDS...). An experience in the use of simulation chambers would be appreciated.
Application: Candidates are invited to send their application by email, including a CV, a summary of their research activities, a list of communications, a cover letter and two recommendation letters.
Salary: About 2100 € monthly net.
Date: The position is available from 01/12/18 to 30/11/2019
Lab location Laboratoire de Physico-Chimie de l'Atmosphère (LPCA) Université du Littoral-Côte d'Opale (ULCO) 189A, avenue Maurice Schumann, 59140 Dunkerque, France
Contact: Dr. C. Coeur (LPCA/ULCO)
LPCA - Postdoctoral (9 month) : Instrument development for measurement of vertical concentration profile of GHGs by LHR / atmospheric radicals by FRS
Keywords : Laser heterodyne radiometry (LHR), mid-IR QCL, greenhouse gases (GHGs), OH radicals, Faraday rotation spectroscopy (FRS)
Project : (1) A mid-infrared laser heterodyne radiometer (LHR) is in development for ground-based in situ measurement of trace gases in the atmospheric column, in particular the development of a fiber coupling device to couple the sunlight to the laser heterodyne receiver which will allow us to realize a fully portable LHR for long-range, long-term and continuous atmospheric observation. The postdoctoral researcher will be involved in the development of the LHR, including: - Optimizing and testing the fiber-coupling system by following the sun movement; - Optimizing and testing the fiber-coupled LHR in lab & in the field; - Testing and validating by field side-by-side inter-comparison measurement.
(2) Development of a laser spectroscopic instrument based on Faraday rotation spectroscopy (FRS) for measurement of free radical OH in the atmosphere, including:
Test, characterization and calibration of the FRS instrument, and validation via intercomparison measurements with well established instruments such as FAGE. This project takes place in the framework of the regional program CLIMIBIO.
Qualifications : The candidate should have a PhD in optics. He/she should have expertise in the followings fields: laser and spectroscopic measurement techniques. Skills in data analysis and computer programming (LabView or equivalent) are also required.
Application : Candidates are invited to send their application by email, including a statement of research activities, a cover letter, a CV, as well name and address of two referees who could provide a recommendation letter.
Salary : About 2100 € monthly net wages. Dates The position can be available from June 1st 2018
Contact : Pr. W. Chen (LPCA/ULCO), +33 (0)3 28 65 82 64
PC2A - Post-doctoral : Soot modelling in premixed flames - Effect of hydrogen and oxygenated compounds on soot nucleation and soot formation
Post-doctoral position at University of Lille (France)
Context and objectives
Reducing soot emissions from combustion processes is a major issue for energy and transportation industries. Many experimental and numerical investigations of sooting flames have been investigated over the past decades and have contributed to significant improvements in the understanding of the soot formation processes. However the transition from the gas phase to the solid phase leading to soot formation is not yet understood and this step is the subject of many efforts at PC2A laboratory by developing highly sensitive diagnostics, PAH modelling and more recently sectional approach for soot modelling*. Particularly all our recent activity is focused on premixed “nucleation flames” which have the special feature of producing nascent soot particles which undergo only minor soot growth along the flames. Therefore these flames are an excellent tool to better understand the nucleation process and have led to new input in soot modeling.
In the continuity of this research we are currently interested in the study of the influence of some additives on the sooting tendency in premixed laminar hydrocarbon flame conditions. The main objective is to identify the impact of hydrogen and oxygenated molecules on both gas and particulate phase chemistry in a wide range of operating conditions (equivalence ratios and proportion of the additives) including near-nucleation conditions.
A recent soot code based on the sectional method has been developed and its association with our kinetic mechanisms has been successfully carried out using Cantera code**. Our group wishes to recruit a postdoctoral researcher to support the development of this new theme. The person hired will support modelling soot volume fraction and particle-size distributions. The candidate is expected to be able to make the necessary improvements to the soot code for predicting the effect of hydrogen and oxygenated compounds on soot nucleation and soot formation.
*Mouton et al. Appl. Phys.B 112,369 (2013) ; Betrancourt et al. Aerosol Sci. Technol. 151, 916 (2017); El Bakali et al. Fuel 211, 548(2018) ; Desgroux et al. Combust. Flame 184, 153 (2017) ;
**Aubagnac-Karkar et al., Combust. Flame 189, 190 (2018)
Ph.D. degree in Chemical or Mechanical Engineering.
The position requires skills in:
- Coding and software development skills (mainly C++/Python, other languages considered) in order to improve the existing sectional soot model implementation in Cantera;
- Detailed soot modelling (sectional or moment methods, stochastic approaches)
This work is supported by CPER CLIMIBIO. Month salary depends on candidate experience. Duration: 15 months. Start: at the latest September 2018.