Title of article :
Sequential multiple analyses of atmospheric nitrous acid and nitrogen oxides
Author/Authors :
Toda، نويسنده , , Kei and Hato، نويسنده , , Yuki and Mori، نويسنده , , Kotaro and Ohira، نويسنده , , Shin-Ichi and Namihira، نويسنده , , Takao، نويسنده ,
Issue Information :
ماهنامه با شماره پیاپی سال 2007
Pages :
9
From page :
1652
To page :
1660
Abstract :
Sequential injection analysis (SIA) was applied to multi-gas monitoring for atmospheric analysis. HONO, NO2 or NO was collected in an individual diffusion scrubber in which the channel array was filled with either HCl or triethanolamine solution. All analytes were collected in the form of nitrite ions in the scrubber, and were transferred via a 12-port selection valve into a 2.5-ml syringe. The reagent, 3-amino-1,5-naphthalenedisulfonic acid (C-acid) solution was subsequently introduced into the syringe, and inter-mixed with the nitrite sample, whereafter the mixed solution was transferred to a heated reactor and held for 3 min at 100 °C. After that, the sample/reagent solution was returned to the syringe and alkalinized. Then, the final solution was analyzed using a homemade fluorescence detector. Atmospheric HONO, NO2 and NO were successfully monitored 3 or 4 times/h. The limits of detection were 0.22, 0.28 and 0.35 ppbv for HONO, NO2 and NO, respectively. It was demonstrated for the first time that SIA is a good tool for multi-gas atmospheric analysis. These nitrogen–oxygen compounds are interconvertible, and the simultaneous measurement of these gases is important. Especially, HONO is a source of OH radicals which contribute greatly to atmospheric pollution, and indeed atmospheric chemistry. This method allows the three gases to be measured using one system. The NO2 and NO data obtained by SIA was compared with those obtained using chemiluminescence instrument. SIA has been successfully applied to atmospheric measurements. Interestingly, it was observed that HONO levels rose toward the end of periods of rain.
Keywords :
Sequential injection analysis , Atmospheric nitrous acid and nitrogen oxides
Journal title :
Talanta
Serial Year :
2007
Journal title :
Talanta
Record number :
1651734
Link To Document :
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