Measurement of NO2 with the PhoNO photolytic converter system

全球分析系统有限公司（GASL）的科学家们已经构建了一种新型光解no2转换器的原型，可用于升级现有的NO/NOx化学发光环境空气监测仪。这些仪器被环境监测机构和排放堆监测仪用来量化NO和no2。目前的版本使用非特异性热金属催化剂将NO2转化为NO，这是通过化学发光来检测的。GASL的目标是开发一种专门针对二氧化氮的转换器。他们正在寻求科学的理解，了解哪些气体和气体混合物会对原型转换器造成干扰，以帮助将其推向市场。Osthoff的团队将量化已知成分的气流中各种气体的原型转换效率，包括NO2（期望）和潜在的干扰气体，如HONO， ClNO2，PAN, N2O5， HO2NO2和HNO3。羰基光化学分解和随后NO氧化为NO2可能产生的干扰将被表征。实验结果将利用光化学箱模型模拟进行合理化。替代石英光解电池（例如，具有较小的内部尺寸）将被构建和评估。最终目标是使GASL能够向市场交付特性良好、成熟且优质的产品。

Scientists at Global Analyzer Systems Ltd. (GASL) have constructed a prototype of a novel photolytic NO2converter that can be used to upgrade existing NO/NOx chemiluminescence ambient air monitors. Theseinstruments are used by environmental monitoring agencies and emission stack monitors to quantify NO andNO2. Current versions use a non-specific hot metal catalyst to convert NO2 to NO, which is detected bychemiluminescence. GASL's goal is to develop a converter that is specific to NO2. They are seeking to developa scientific understanding of what gases and gas mixtures cause interferences in the prototype converter to helpbring it to market.Dr. Osthoff's group will quantify the conversion efficiency in the prototype of a variety of gases in gas streamsof known composition, including NO2 (desired) and potentially interfering gases such as HONO, ClNO2,PAN, N2O5, HO2NO2, and HNO3. Interference that might arise from photochemical decomposition ofcarbonyls and subsequent oxidation of NO to NO2 will be characterized. The experimental results will berationalized using photochemical box model simulations.Alternative quartz photolysis cells (e.g., with smaller inner dimensions) will be constructed and evaluated. Theultimate goal is to allow GASL to deliver a well-characterized, mature, and superior product to market.