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Article: Study results from H. Fuchs and colleagues update understanding of science and technology.
- Article from:
- Ecology, Environment & Conservation
- Article date:
- November 13, 2009
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"A sensitive, small detector was developed for atmospheric NO2 and NOx concentration measurements. NO2 is directly detected by laser diode based cavity ring-down spectroscopy (CRDS) at 404 nm," scientists writing in the journal Environmental Science & Technology report.
"The sum of NO and NO2 (=NOx) is simultaneously measured in a second cavity by quantitative conversion of ambient NO to NO2 in excess ozone. Interferences due to absorption by other trace gases at 404 nm, such as ozone and water vapor, are either negligible or small and are easily quantified. The limit of detection is 22 pptv (2 sigma precision) for NO2 at 1 s time resolution. The conversion ...