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. 2020 Aug 25;12(1):124–133. doi: 10.1016/j.apr.2020.08.028

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© 2020 Turkish National Committee for Air Pollution Research and Control. Production and hosting by Elsevier B.V.

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Fig. 3 — Mean dirunal variation of CO (blue) and C₃H₆ (propene, red) before (solid lines) and after (dashed lines) the COVID-19 lockdown (Jan-13 March and 14 March–April, respectively). CO is the average from three City stations. Propene was derived by scaling CO (for other VOCs see Appendix S3).