Js. Gaffney et al., Aircraft measurements of nitrogen dioxide and peroxyacyl nitrates using luminol chemiluminescence with fast capillary gas chromatography, ENV SCI TEC, 33(19), 1999, pp. 3285-3289
Citations number
19
Categorie Soggetti
Environment/Ecology,"Environmental Engineering & Energy
Fast capillary gas chromatography with luminol detection has been used to m
ake airborne measurements of nitrogen dioxide (NO2) and peroxyacetyl nitrat
e (PAN). The analysis system allows for the simultaneous measurement of NO2
and peroxyacyl nitrates (PANs) with time resolution of less than 1 min, an
improvement of a factor of 4-5 over previously reported methods using elec
tron capture detection. Data presented were taken near Pasco, Washington, i
n August 1997, during a test flight onboard the U.S. Department of Energy G
-1 aircraft. We report measurements of NO2 in the boundary layer in a paper
mill plume and a plume from a grass fire, in addition to analyses for free
tropospheric NO2 and PAN. Ratios of PAN/NO2 were observed to increase with
altitude (decreasing temperature) and to reach values of 2-4 above the bou
ndary layer, consistent with the thermal equilibrium of the peroxyacetyl ra
dical and NO2 with PAN. Estimates for the peroxyacetyl radical in the conti
nental free troposphere, calculated from this equilibrium, were found to be
in the range of 10(4)-10(5) molecules per cubic centimeter. These results
demonstrate the application of this approach for airborne measurements of N
O2 and PAN in a wide range of field study scenarios.