A method for extracting calibrated volatility information from the FIGAERO-HR-ToF-CIMS and its experimental application
A method for extracting calibrated volatility information from the FIGAERO-HR-ToF-CIMS and its experimental application
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DOI：
10.5194/amt-12-1429-2019
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发表时间：
2019-03
影响因子：
3.8
通讯作者：
T. Bannan;Michael Le Breton;M. Priestley;S. Worrall;A. Bacak;N. Marsden;Archit Mehra;Julia Hammes;M. Hallquist;M. Alfarra;U. Krieger;J. Reid;J. Jayne;W. Robinson;G. Mcfiggans;H. Coe;C. Percival;D. Topping
中科院分区：
文献类型：
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作者：
T. Bannan;Michael Le Breton;M. Priestley;S. Worrall;A. Bacak;N. Marsden;Archit Mehra;Julia Hammes;M. Hallquist;M. Alfarra;U. Krieger;J. Reid;J. Jayne;W. Robinson;G. Mcfiggans;H. Coe;C. Percival;D. Topping
抽象。气体和气溶胶过滤器入口（FIGAERO）是专门设计用于与Aerodyne高分辨率飞行时间化学电离质谱仪（HR-ToF-CIMS）耦合的入口。FIGAERO-HR-ToF-CIMS同时提供与气相和颗粒相样品相关的分子信息，并已用于提取从过滤器解吸的化合物的蒸气压（VP），同时给出颗粒相中的定量浓度。然而，这种对测量的颗粒相组分的蒸气压的提取需要使用适当的、明确定义的参比化合物。聚乙二醇（PEG）（（H-（O-CH 2-CH 2）n-OH），n=3至n=8）的同系蒸汽压，涵盖了与大气相关的蒸汽压（VP）范围（10−1至10−7 Pa），已被证明可以通过一系列不同的技术，包括克努森效应质谱（KEMS），很好地再现。这是第一个同源系列的化合物，对于这些化合物，已经发现许多蒸气压测量技术是一致的，表明其作为校准标准的实用性，为FIGAERO的准确表征提供了一套理想的基准化合物，用于提取室和真实的大气中测量化合物的蒸气压。为了证明这一点，基于从PEG系列确定的新校准，使用两台FIGAERO-HR-ToF-CIMS仪器进行单组分和混合物蒸气压测量。从这两种仪器中提取的VP值与KEMS测量的值和文献中的报告值吻合良好，验证了从FIGAERO中提取VP数据的方法。然后将该方法应用于腔室测量，并估计已知产品的蒸气压。
Abstract. The Filter Inlet for Gases and AEROsols (FIGAERO) is an inlet specifically designed to be coupled with the Aerodyne High-Resolution Time-of-Flight Chemical Ionization Mass Spectrometer (HR-ToF-CIMS). The FIGAERO-HR-ToF-CIMS provides simultaneous molecular information relating to both the gas- and particle-phase samples and has been used to extract vapour pressures (VPs) of the compounds desorbing from the filter whilst giving quantitative concentrations in the particle phase. However, such extraction of vapour pressures of the measured particle-phase components requires use of appropriate, well-defined, reference compounds. Vapour pressures for the homologous series of polyethylene glycols (PEG) ((H-(O-CH2-CH2)n-OH) for n=3 to n=8), covering a range of vapour pressures (VP) (10−1 to 10−7 Pa) that are atmospherically relevant, have been shown to be reproduced well by a range of different techniques, including Knudsen Effusion Mass Spectrometry (KEMS). This is the first homologous series of compounds for which a number of vapour pressure measurement techniques have been found to be in agreement, indicating the utility as a calibration standard, providing an ideal set of benchmark compounds for accurate characterization of the FIGAERO for extracting vapour pressure of measured compounds in chambers and the real atmosphere. To demonstrate this, single-component and mixture vapour pressure measurements are made using two FIGAERO-HR-ToF-CIMS instruments based on a new calibration determined from the PEG series. VP values extracted from both instruments agree well with those measured by KEMS and reported values from literature, validating this approach for extracting VP data from the FIGAERO. This method is then applied to chamber measurements, and the vapour pressures of known products are estimated.