title: NitroMAC: An instrument for the measurement of HONO and intercomparison with a long-path absorption photometer.
abstract: NitroMAC (French acronym for continuous atmospheric measurements of nitrogenous compounds) is an instrument which has been developed for the semi-continuous measurement of atmospheric nitrous acid (HONO). This instrument relies on wet chemical sampling and detection using high performance liquid chromatography (HPLC)-visible absorption at 540 nm. Sampling proceeds by dissolution of gaseous HONO in a phosphate buffer solution followed by derivatization with sulfanilamide/N-(1-naphthyl)-ethylenediamine. The performance of this instrument was found to be as follows: a detection limit of around 3 ppt with measurement uncertainty of 10% over an analysis time of 10 min. Intercomparison was made between the instrument and a long-path absorption photometer (LOPAP) during two experiments in different environments. First, air was sampled in a smog chamber with concentrations up to 18 ppb of nitrous acid. NitroMAC and LOPAP measurements showed very good agreement. Then, in a second experiment, ambient air with HONO concentrations below 250 ppt was sampled. While NitroMAC showed its capability of measuring HONO in moderate and highly polluted environments, the intercomparison results in ambient air highlighted that corrections must be made for minor interferences when low concentrations are measured.
authors.affiliation: Emissions, Measurements and Modeling of the Atmosphere Laboratory, EGFEM Unit, Center for Analysis and Research, Faculty of Sciences, Saint Joseph University, Beirut, Lebanon; Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583, CNRS, Université Paris-Est-Créteil (UPEC) et Université Paris Diderot (UPD), Institut Pierre Simon Laplace (IPSL), Créteil, France. Electronic address: afif@lisa.u-pec.fr.
authors.forename: Charbel
authors.initials: C
authors.lastname: Afif
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583, CNRS, Université Paris-Est-Créteil (UPEC) et Université Paris Diderot (UPD), Institut Pierre Simon Laplace (IPSL), Créteil, France.
authors.forename: Corinne
authors.initials: C
authors.lastname: Jambert
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583, CNRS, Université Paris-Est-Créteil (UPEC) et Université Paris Diderot (UPD), Institut Pierre Simon Laplace (IPSL), Créteil, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Michoud
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583, CNRS, Université Paris-Est-Créteil (UPEC) et Université Paris Diderot (UPD), Institut Pierre Simon Laplace (IPSL), Créteil, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Colomb
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, CNRS, Orléans, France.
authors.forename: Gregory
authors.initials: G
authors.lastname: Eyglunent
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583, CNRS, Université Paris-Est-Créteil (UPEC) et Université Paris Diderot (UPD), Institut Pierre Simon Laplace (IPSL), Créteil, France.
authors.forename: Agnès
authors.initials: A
authors.lastname: Borbon
authors.affiliation: Institut de Combustion, Aérothermique, Réactivité et Environnement, CNRS, Orléans, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Daële
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583, CNRS, Université Paris-Est-Créteil (UPEC) et Université Paris Diderot (UPD), Institut Pierre Simon Laplace (IPSL), Créteil, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Doussin
authors.affiliation: Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583, CNRS, Université Paris-Est-Créteil (UPEC) et Université Paris Diderot (UPD), Institut Pierre Simon Laplace (IPSL), Créteil, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Perros
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001272:Atmosphere; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D005602:France; D057230:Limit of Detection; D009608:Nitrous Acid / Q000032:analysis*; D010783:Photometry / Q000295:instrumentation / Q000379:methods
chemical_list: D000393:Air Pollutants; D009608:Nitrous Acid
keywords: Atmospheric measurements; French acronym for continuous atmospheric measurements of nitrogenous compounds (NitroMAC); Long-path absorption photometer; Nitrous acid; Sulfanilamide/N-(1-naphthyl)-ethylenediamine