Abstract
In September 2017, we conducted a proton-transfer-reaction mass-spectrometry (PTR-MS) intercomparison campaign at the CESAR observatory, a rural site in the central Netherlands near the village of Cabauw. Nine research groups deployed a total of 11 instruments covering a wide range of instrument types and performance. We applied a new calibration method based on fast injection of a gas standard through a sample loop. This approach allows calibrations on timescales of seconds, and within a few minutes an automated sequence can be run allowing one to retrieve diagnostic parameters that indicate the performance status. We developed a method to retrieve the mass-dependent transmission from the fast calibrations, which is an essential characteristic of PTR-MS instruments, limiting the potential to calculate concentrations based on counting statistics and simple reaction kinetics in the reactor/drift tube. Our measurements show that PTR-MS instruments follow the simple reaction kinetics if operated in the standard range for pressures and temperature of the reaction chamber (i.e. 1-4 mbar, 30-120<span classCombining double low line"inline-formula">ĝ'</span>, respectively), as well as a reduced field strength <span classCombining double low line"inline-formula">Eĝ'•N</span> in the range of 100-160 Td. If artefacts can be ruled out, it becomes possible to quantify the signals of uncalibrated organics with accuracies better than <span classCombining double low line"inline-formula">±30</span> %. The simple reaction kinetics approach produces less accurate results at <span classCombining double low line"inline-formula">Eĝ'•N</span><span idCombining double low line"page6194"/> levels below 100 Td, because significant fractions of primary ions form water hydronium clusters. Deprotonation through reactive collisions of protonated organics with water molecules needs to be considered when the collision energy is a substantial fraction of the exoergicity of the proton transfer reaction and/or if protonated organics undergo many collisions with water molecules.
Original language | English |
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Pages (from-to) | 6193-6208 |
Number of pages | 16 |
Journal | Atmospheric Measurement Techniques |
Volume | 12 |
Issue number | 11 |
DOIs | |
Publication status | Published - 27 Nov 2019 |
Bibliographical note
Funding Information:Acknowledgements. This project has received funding from the European Union’s Horizon 2020 research and innovation programme (ACTRIS-2) under grant agreement no. 654109 and by the Dutch NWO Earth and Life Science (ALW), project 824.14.002. W. Joe F. Acton, Martin Breitenlechner, Leigh R. Crilley, Louisa J. Kramer, Jordan E. Krechmer, Felipe Lopez-Hilfiker, Eiko Nemitz, Lauri-ane L. J. Quéléver, Simon Schallhart, Ralf Tillmann, Sergej Wedel, and Alexander Zaytsev acknowledge Transnational Access (TNA) travel funding from ACTRIS-2 (grant agreement no. 654109). Eiko Nemitz further acknowledges the support of the UK Natural Environment Research Council (NERC) through grants NE/P016502/1 for instrument funding and NE/R016429/1 as part of the UK-SCaPE programme delivering National Capability. Lauriane L. J. Quéléver and Simon Schallhart acknowledge the Finnish Centre of Excellence program (Project no 307331). Lauriane L. J. Quéléver thank the European Research Council (ERC grant no. 638703-COALA). W. Joe F. Acton has received funding from Natural Environment Research Council (UK) grant NE/N006976/1, Sources and Emissions of Air Pollutants in Beijing (AIRPOLL-Beijing).
Funding Information:
pean Commission (ACTRIS-2, grant no. 654109) and the Netherlands Organisation for Scientific Research (NWO) (grant no. 824.14.002).
Publisher Copyright:
© Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License.
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
ASJC Scopus subject areas
- Atmospheric Science