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| Titel |
Measurement of atmospheric NO2 and NOx by a small, sensitive diode laser based cavity ring-down detector at 404 nm |
| VerfasserIn |
H. Fuchs, W. P. Dubé, B. M. Lerner, N. L. Wagner, E. J. Williams, S. S. Brown |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250020201
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| Zusammenfassung |
| A new, cavity ring-down detector was developed for the detection of atmospheric
NO2 and NOx. NO2 is directly measured by laser diode based cavity ring-down
spectroscopy at 404 nm. In contrast to the indirect detection in most commonly
used chemiluminescence detectors, the direct measurement of NO2 may be useful
especially in cases where NO to NO2 ratios are large such as in freshly emitted
plumes from combustion processes. The extinction of ambient air is dominated by the
absorption of NO2 so that the instrument does not exhibit significant interferences due to
other absorbers such as ozone or water vapor. The limit of detection is 22 pptv (2σ
precision) for NO2 at 1 s time resolution. The accuracy of the NO2 measurement
is given by the uncertainty of the NO2 absorption cross section to |
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