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. 2021 Oct 19;807:151084. doi: 10.1016/j.scitotenv.2021.151084

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© 2021 Published by Elsevier B.V.

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Fig. 1 — Changes of the mask mass loss (a, b, c) and pH value of the hydrolytic soaking solutions (d, e, f) with different degradation periods under neutral (pH = 7), acid (pH = 2) and basic (pH = 13) conditions, respectively.