Abstract
Abstract. A compact and simple instrument for the sensitive detection of NO2 in the atmosphere has been developed. NO2 is sampled in a stripping coil by a selective chemical reaction, converted into a highly absorbing dye, which is detected by long path absorption in a liquid core waveguide. Several interferences were quantified in the laboratory which so far can all be neglected. The significant interferences against HONO and O3 were suppressed by using an upstream HONO/O3-scrubber. The instrument has a detection limit of 2 pptv, an accuracy of 10 % and a precision of 0.5 % for 3 min time resolution. Thus, the new NO2-LOPAP technique is more sensitive than known commercial NO2 instruments. The new analyzer is much simpler to apply than other highly sensitive and selective NO2 methods, e.g. LIF or REMPI methods. The new instrument allows an absolute calibration that can be easily performed with liquid nitrite standards, which is a significant advantage compared with other NO2 measurement techniques for which NO2 calibration gas mixtures are typically necessary. The new instrument has been validated against the chemiluminescence technique during an urban field campaign and against the FTIR technique in a smog chamber under complex photosmog conditions. The data sets exhibit high correlation and excellent agreement.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.