Composition of Individual Particles Segregated According to Electrical Mobility, Hygroscopicity, Volatility and Mass

市售的气溶胶飞行时间质谱仪（ATOFMS）将用于测量根据各种物理性质预先分类的颗粒的组成。这些测量将为大气颗粒的物理/化学性质和混合特性提供新的见解。这些信息对于解释来自更传统仪器的数据很有价值，并可用于评估描述各种来源的气溶胶作为大小和成分的函数的演变的最新模型。颗粒将根据电迁移率（大小）与差分迁移率分析仪（DMA），大小和吸湿性与串联差分迁移率分析仪（TDMA），或大小与DMA或TDMA和质量与气溶胶粒子质量分析仪（APM）进行分类。在ATOFMS分析之前，将通过加热粒度分类颗粒来研究挥发对成分的影响。该项目的头两年将集中研究已知成分的实验室气溶胶，并制定实地测量的抽样方案。将在佐治亚州亚特兰大开展密集的实地行动。该项目是明尼苏达大学和卡尔顿学院的合作项目。

A commercially available Aerosol Time of Flight Mass Spectrometer (ATOFMS) will be used to measure the composition of particles that have been preclassified according to various physical properties. These measurements will provide new insights into the physical/chemical properties and mixing characteristics of atmospheric particles. Such information is valuable for interpreting data from more conventional instrumentation and can be used to evaluate state-of-the-art models that describe the evolution of aerosols from various sources as a function of size and composition. Particles will be classified according to electrical mobility (size) with a differential mobility analyzer (DMA), size and hygroscopicity with a tandem differential mobility analyzer (TDMA), or size with a DMA or TDMA and mass with an Aerosol Particle Mass Analyzer (APM). The effect of volatilization on composition will be studied by heating size-classified particles before analyzing them with the ATOFMS.The first two years of the project will focus on studies with laboratory aerosols of known composition and on the development of sampling protocols for field measurements. An intensive field campaign will be carried out in Atlanta, GA. This project represents a collaboration between the University of Minnesota and Carleton College.