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Titel |
Design of a new multi-phase experimental simulation chamber for atmospheric photosmog, aerosol and cloud chemistry research |
VerfasserIn |
J. Wang, J. F. Doussin, S. Perrier, E. Perraudin, Y. Katrib, E. Pangui, B. Picquet-Varrault |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1867-1381
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Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Measurement Techniques ; 4, no. 11 ; Nr. 4, no. 11 (2011-11-24), S.2465-2494 |
Datensatznummer |
250002136
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Publikation (Nr.) |
copernicus.org/amt-4-2465-2011.pdf |
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Zusammenfassung |
A new simulation chamber has been built at the Interuniversitary Laboratory
of Atmospheric Systems (LISA). The CESAM chamber (French acronym for
Experimental Multiphasic Atmospheric Simulation Chamber) is designed to
allow research in multiphase atmospheric (photo-) chemistry which involves
both gas phase and condensed phase processes including aerosol and cloud
chemistry. CESAM has the potential to carry out variable temperature and
pressure experiments under a very realistic artificial solar irradiation. It
consists of a 4.2 m3 stainless steel vessel equipped with three high
pressure xenon arc lamps which provides a controlled and steady environment.
Initial characterization results, all carried out at 290–297 K under dry
conditions, concerning lighting homogeneity, mixing efficiency, ozone
lifetime, radical sources, NOy wall reactivity, particle loss rates,
background PM, aerosol formation and cloud generation are given. Photolysis
frequencies of NO2 and O3 related to chamber radiation system were
found equal to (4.2 × 10−3 s−1) for JNO2 and
(1.4 × 10−5 s−1) for JO1D which is comparable to the
solar radiation in the boundary layer. An auxiliary mechanism describing NOy
wall reactions has been developed. Its inclusion in the Master Chemical
Mechanism allowed us to adequately model the results of experiments on the
photo-oxidation of propene-NOx-Air mixtures. Aerosol yields for the
α-pinene + O3 system chosen as a reference were determined and found in
good agreement with previous studies. Particle lifetime in the chamber
ranges from 10 h to 4 days depending on particle size distribution which
indicates that the chamber can provide high quality data on aerosol aging
processes and their effects. Being evacuable, it is possible to generate in
this new chamber clouds by fast expansion or saturation with or without the
presence of pre-existing particles, which will provide a multiphase
environment for aerosol-droplet interaction. |
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