Rapid isotopic analysis of trace gases at atmospheric levels

Abstract A method is reported allowing simultaneous isotopic analysis of N2 and N2O at atmospheric concentrations. A gas chromatograph fitted with a thermal conductivity detector and micro desorption trap was interfaced to an isotope ratio mass spectrometer (Tracer Mass, Europa Scientific, Crewe, UK). CO2 and H2O were chemically removed prior to the complete sorption of N2O onto a zeolite bed. N2 was chromatographically purified prior to isotopic analysis. The N2O was thermally desorbed into a slow carrier stream (300 μL min−1) prior to analysis at m/z 44, 45 and 46. Precision of measurement was 0.3663 ± 0.000013 and 0.365 ± 0.0025 Atom % 15N as N2 and N2O respectively. The method was then evaluated for a soil denitrification experiment. Es wird uber eine Methode zur simultanen Isotopenanalyse am N2 und N2O bei atmospharischer Konzentration berichtet. Ein Gaschromatograph mit Warmeleitfahigkeitsdetektor und Mikrodesorptionsfalle wurde an ein IRM-Massenspektrometer (Tracer Mass, Europa Scientific, Crewe, G...