Acquisition of a Real-Time, API-TOFMS Monitor for Use with aMobile Test Gas Generation Facility

描述对流层痕量气体成分和化学反应性的愿望刺激了各种仪器方法的发展，用于分析低十亿分之一和万亿分之一浓度的大气气体。为了评估独立分析方法之间的定量一致性，大气化学界提倡使用正式的相互比较。该奖项的主要研究者开发了一种便携式动态稀释系统，用于制备含有已知pptv量的各种含硫气体的合成气体混合物。该系统最近成功地应用于二氧化硫的相互比较。 将该系统的使用扩展到非硫化合物的一个重要步骤是开发增强的测量能力，用于测试和监测由改进的气体输送系统制备的不同测试气流。 该合同旨在开发基于大气压电离/飞行时间质谱仪（API-TOFMS）的这种能力。 API-TOFMS将提供快速的响应时间，同时实时监测几种分析物和相对的设计简单性和可靠的现场操作的鲁棒性。 该仪器将扩大气体稀释系统的使用范围，以追踪大气化合物，如氮气、卤化气体、醛和酮以及生物碳氢化合物。它还将有助于教育和培训青年科学家，使他们了解痕量物种测量质量保证的重要性。

The desire to characterize the trace gas composition and chemical reactivity of the troposphere has stimulated the development of various instrumental methods for the analysis of atmospheric gases at low part-per-billion and part-per-trillion concentrations. In order to assess the quantitative agreement between independent analysis methods, the atmospheric chemistry community has promoted the use of formal intercomparisons. The principal investigator of this award has developed a portable dynamic dilution system for the preparation of synthetic gas mixtures containing known pptv amounts of various sulfur gases. This system was recently employed successfully in an intercomparison focused on sulfur dioxide. An important step in extending the use of this system to non-sulfur compounds is the development of an enhanced measurement capability for testing and monitoring the different test gas streams prepared by the modified gas delivery system. This award is to develop such a capability based on an atmospheric pressure ionization/time-of-flight mass spectrometer (API-TOFMS). The API-TOFMS will provide rapid response time for simultaneous real-time monitoring of several analytes and relative design simplicity and robustness for dependable field operation. The instrument will extend the use of the gas dilution system to trace atmospheric compounds such as nitrogen gases, halogenated gases, aldehydes and ketones, and biogenic hydrocarbons. It will also contribute to the education and training of young scientists related to the importance of quality assurance for trace species measurements.