Amines are potentially important for atmospheric new particle formation, but their concentrations are usually low with typical mixing ratios in the pptv range or even smaller. Therefore, the demand for highly sensitive gas-phase amine measurements has emerged in the last several years. Nitrate chemical ionization mass spectrometry (CIMS) is routinely used for the measurement of gasphase sulfuric acid in the sub-pptv range. Furthermore, extremely low volatile organic compounds (ELVOCs) can be detected with a nitrate CIMS. In this study we demonstrate that a nitrate CIMS can also be used for the sensitive measurement of dimethylamine (DMA, (CH3/2NH) using the NO3−•(HNO3)1 − 2• (DMA) cluster ion signal. Calibration measurements were made at the CLOUD chamber during two different measurement campaigns. Good linearity between 0 and ~120 pptv of DMA as well as a sub-pptv detection limit of 0.7 pptv for a 10 min integration time are demonstrated at 278K and 38% RH.
Amines are potentially important for atmospheric new particle formation, but their concentrations are usually low with typical mixing ratios in the pptv range or even smaller. Therefore, the demand for highly sensitive gas-phase amine measurements has emerged in the last several years. Nitrate chemical ionization mass spectrometry (CIMS) is routinely used for the measurement of gas-phase sulfuric acid in the sub-pptv range. Furthermore, extremely low volatile organic compounds (ELVOCs) can be detected with a nitrate CIMS. In this study we demonstrate that a nitrate CIMS can also be used for the sensitive measurement of dimethylamine (DMA, (CH3)2NH) using the NO3−•(HNO3)1 − 2• (DMA) cluster ion signal. Calibration measurements were made at the CLOUD chamber during two different measurement campaigns. Good linearity between 0 and ∼ 120 pptv of DMA as well as a sub-pptv detection limit of 0.7 pptv for a 10 min integration time are demonstrated at 278 K and 38 % RH.
Die Schadstoffbelastung der Muldeaue ist ein Problem, das schon lange besteht, aber erst nach 1 989 offiziell behandelt wurde. Das Hauptbelastungspotential dieses Gebietes bilden Schwermetalle und chlorierte Kohlenwasserstoffe, insbesondere das der Lindanproduktion entstammende Hexachlorcyclohexan (ß-HCH). Diese Stoffe wurden aus dem in Südsachsen betriebenen Erzbergbau bzw. aus den chemischen Großbetrieben im Landkreis Bitterfeld über Abwässer permanent in die Mulde eingebracht. Mit den periodisch auftretenden Hochwässern kam es durch die Aufschwemmung von Sedimenten zu einer großflächigen Kontamination des Überflutungsgebietes im Landkreis Bitterfeld und der kreisfreien Stadt Dessau.
