Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.
AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.
In this work, a method combining polar organic chemical integrative samplers (POCIS) and ultraperformance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) was assessed for the determination of two corrosion inhibitors (benzotriazole and methylbenzotriazole), seven pesticides (atrazine, diuron, isoproturon, linuron, metolachlor, penconazole, terbuthylazine), and four pharmaceuticals (carbamazepine, diclofenac, metformin, sulfamethoxazole) in river water. As a first step, two POCIS sorbents, hydrophilic-lipophilic balance (HLB) and Strata X-CW, were compared. The comparison of the uptake profiles of the studied compounds showed that the HLB sorbent provides better uptake (higher sampled amount and better linearity) than Strata X-CW except for the basic compound metformin. Since the sampling rate (Rs) of POCIS depends on environmental factors, seven compounds were evaluated as potential performance reference compounds (PRCs) through kinetic experiments. Deisopropylatrazine-d5 (DIA-d5) and, as far as we know, for the first time 4-methylbenzotriazole-d3 showed suitable desorption. The efficiency of both compounds to correct for the effect of water velocity was shown using a channel system in which POCIS were exposed to 2 and 50 cm s−1. Finally, POCIS were deployed upstream and downstream of agricultural wine-growing and tree-growing areas in the Lienne River and the Uvrier Canal (Switzerland). The impact of the studied areas on both streams could be demonstrated.