| Autor: |
Dubé, William P., Brown, Steven S., Osthoff, Hans D., Nunley, Maya R., Ciciora, Steven J., Paris, Mark W., McLaughlin, Richard J., Ravishankara, A. R. |
| Předmět: |
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| Zdroj: |
Review of Scientific Instruments; Mar2006, Vol. 77 Issue 3, p034101, 11p, 3 Diagrams, 5 Graphs |
| Abstrakt: |
This article describes a cavity ring-down spectrometer (CaRDS) specifically designed and constructed for installation on the NOAA WP-3D Orion (P-3) aircraft for sensitive, rapid in situ measurement of NO3 and N2O5. While similar to our previously described CaRDS instrument, this instrument has significant improvements in the signal-to-noise ratio, the time resolution, and in overall size and weight. Additionally, the instrument utilizes a custom-built, automated filter changer that was designed and constructed to meet the requirement for removal of particulate matter in the airflow while allowing fully autonomous instrument operation. The CaRDS instrument has a laboratory detection sensitivity of 4×10-11 cm-1 in absorbance or 0.1 pptv (pptv denotes parts per trillion volume) of NO3 in a 1 s average, although the typical detection sensitivities encountered in the field were 0.5 pptv for NO3 and 1 pptv for N2O5. The instrument accuracy is 25% for NO3 and 20%–40% for N2O5, limited mainly by the uncertainty in the inlet transmission. The instrument has been deployed on the P-3 aircraft as part of a major field campaign in the summer of 2004 and during several ground and tower deployments near Boulder, CO. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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