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. 2020 May 28;737:139765. doi: 10.1016/j.scitotenv.2020.139765

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Fig. 5 — Changes in hourly averages of NO_x, NMHC, NMHC/NO_x ratio and O₃ at the monitoring station of Irajá, from March 1 to April 16, 2020. The green, red and blue lines show the hourly trends before the partial lockdown (03/01/2020–03/22/2020), during the partial lockdown (03/23/2020–04/05/2020) and after the relaxing of the lockdown (04/06/2020–04/16/2020). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)