Variables: dissolved_oygen electric_conductivity concentration Keywords: high resolution mass spectrometry Substances: 18-beta-Glycyrrhetinic acid (MPDGHEJMBKOTSU-YKLVYJNSSA-N) 1-Propanesulfonate (KCXFHTAICRTXLI-UHFFFAOYSA-N) 4-Methyl-Benzotriazole (CMGDVUCDZOBDNL-UHFFFAOYSA-N)