Spanel P, Smith D
J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Prague.
Rapid Commun Mass Spectrom. 2000;14(8):646-51. doi: 10.1002/(SICI)1097-0231(20000430)14:8<646::AID-RCM926>3.0.CO;2-7.
A selected ion flow tube (SIFT) experimental investigation has been carried out of the reactions of H3O+, NO+ and O2+ with NO, NO2, N2O and HNO2, in order to obtain the essential kinetic data for the analyses of these compounds in air using selected ion flow tube mass spectrometry (SIFT-MS). These investigations show that NO+ ions do not react at a significant rate with any of these NOx compounds and that H3O+ ions react only with HNO2 (product ions H2NO2+ (75%) and NO+ (25%)). O2+ ions react with NO (product ion NO+), NO2 (product ion NO2+) and HNO2 (product ions NO+ (75%), NO2+ (25%)), but not with N2O. We conclude that both NO and NO2 can be accurately quantified in air using only O2+ precursor ions and SIFT-MS when HNO2 is not present. However, when HNO2 is present it invariably co-exists with both NO and NO2 and then both H3O+ and O2+ precursor ions are needed to determine the partial pressures of NO, NO2 and HNO2 in the air mixture. We also conclude that currently N2O cannot be analysed in air using SIFT-MS.
为了获得使用选择离子流管质谱法（SIFT-MS）分析空气中这些化合物所需的基本动力学数据，对H3O+、NO+和O2+与NO、NO2、N2O和HNO2的反应进行了选择离子流管（SIFT）实验研究。这些研究表明，NO+离子与这些氮氧化物化合物中的任何一种都不会以显著速率反应，并且H3O+离子仅与HNO2反应（产物离子为H2NO2+（75%）和NO+（25%））。O2+离子与NO（产物离子为NO+）、NO2（产物离子为NO2+）和HNO2（产物离子为NO+（75%）、NO2+（25%））反应，但不与N2O反应。我们得出结论，当不存在HNO2时，仅使用O2+前体离子和SIFT-MS就可以准确量化空气中的NO和NO2。然而，当存在HNO2时，它总是与NO和NO2共存，然后需要H3O+和O2+前体离子来确定空气混合物中NO、NO2和HNO2的分压。我们还得出结论，目前无法使用SIFT-MS分析空气中的N2O。
