Variables: dissolved_organic_carbon total_organic_carbon Substances: 1-3-Dimethyl-2-imidazolidinon (CYSGHNMQYZDMIA-UHFFFAOYSA-N) 1-Hydroxy-Benzotriazole (ASOKPJOREAFHNY-UHFFFAOYSA-N) 4-Aminopyrin (4-Aminoantipyrin 4-AA) (RLFWWDJHLFCNIJ-UHFFFAOYSA-N)