Prediction of Toxic Semi-Volatile Organic Gas-Particle Partitioning in the Atmosphere with the Use of Activity Coefficients

9708533卡门斯这项研究的主要目标是显著提高我们计算半挥发性有机有毒化合物的平衡分配的能力，半挥发性有机有毒化合物分布在气相和气溶胶之间。这将专门针对具有有机液层的颗粒，例如来自柴油、木材燃烧和二次有机气雾剂的颗粒。将研究含有环境排放或产生的有机酸、羰基、氯化有机物、烷烃、多环芳香烃和环状硅氧烷的化合物类别的分配。用基团贡献法计算有机物在给定液体颗粒混合物中的活度系数。然后，这些活度系数将与蒸汽压和其他气溶胶性质一起用于计算平衡分配常数。将进行室外小室测量，以提供气体-颗粒分配数据。由于气溶胶化学成分和大气湿度对活度系数的预测有很大影响，将在恒定湿度下用已知的气溶胶成分进行初步试验。稍后的实验将研究更复杂的粒子系统。

9708533 Kamens The main objective of this research is to dramatically improve our ability to calculate the equilibrium partitioning of semi-volatile organic toxic compounds, which distribute between gas and aerosol phases. This will be done specifically for particles which have organic liquid layers, such as particles from diesel fuel, wood combustion, and secondary organic aerosols. The partitioning of compound classes which contain environmentally emitted or created organic acids, carbonyls, chlorinated organics, alkanes, polynuclear aromatic hydrocarbons, and cyclical siloxanes, will be investigated. The activity coefficients of the organics in given liquid particle mixtures will be calculated using the group contribution method. These activity coefficients will then be used along with vapor pressures and other aerosol properties to calculate equilibrium partitioning constants. Outdoor chamber measurements will be performed to provide gas-particle partitioning data. Since aerosol chemical composition and atmospheric humidity strongly influence activity coefficient predictions, initial experiments will be carried out with known aerosol compositions at constant humidities. Later experiments will investigate more complex particle systems.