title: Comparison of methods to determine triple oxygen isotope composition of N2O.
abstract: BACKGROUND
  The oxygen isotope anomaly, Δ(17) O, of N2 O and nitrate is useful to elucidate nitrogen oxide dynamics. A comparison of different methods for Δ(17) O measurement was performed.
  
  
  METHODS
  For Δ(17) O measurements, N2 O was converted into O2 and N2 using microwave-induced plasma in a quartz or corundum tube reactor, respectively, or conversion was carried out in a gold wire oven. In each case, isotope ratios were measured by isotope ratio mass spectrometry.
  
  
  RESULTS
  All the tested methods showed acceptable precision (coefficient of variation <2.4 % at 160 nmol N2 O) with high sample size but the sample size dependence was lowest when using microwave-induced plasma in a corundum tube reactor.
  
  
  CONCLUSIONS
  The use of microwave-induced plasma in a corundum tube yields best results for Δ(17) O measurement on N2 O gas samples.
authors.affiliation: Centre for Stable Isotope Research and Analysis, Georg-August University of Göttingen, Büsgenweg 2, 37077, Göttingen, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Dyckmans
authors.affiliation: Thünen Institute of Climate-Smart Agriculture, Bundesallee 50, 38116, Braunschweig, Germany.
authors.forename: Dominika
authors.initials: D
authors.lastname: Lewicka-Szczebak
authors.affiliation: Centre for Stable Isotope Research and Analysis, Georg-August University of Göttingen, Büsgenweg 2, 37077, Göttingen, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Szwec
authors.affiliation: Centre for Stable Isotope Research and Analysis, Georg-August University of Göttingen, Büsgenweg 2, 37077, Göttingen, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Langel
authors.affiliation: Thünen Institute of Climate-Smart Agriculture, Bundesallee 50, 38116, Braunschweig, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Well
mesh_terms: D013058:Mass Spectrometry / Q000379:methods*; D009584:Nitrogen / Q000737:chemistry; D009609:Nitrous Oxide / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D010103:Oxygen Isotopes / Q000737:chemistry
chemical_list: D010103:Oxygen Isotopes; D009609:Nitrous Oxide; D009584:Nitrogen; D010100:Oxygen