Donahue N M, Robinson A L, Stanier C O, Pandis S N
Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Environ Sci Technol. 2006 Apr 15;40(8):2635-43. doi: 10.1021/es052297c.
A unified framework of semi-volatile partitioning permits models to efficiently treat both semi-volatile primary emissions and secondary organic aerosol production (SOA), and then to treat the chemical evolution (aging) of the aggregate distribution of semi-volatile material. This framework also reveals critical deficiencies in current emissions and SOA formation measurements. The key feature of this treatment is a uniform basis set of saturation vapor pressures spanning the range of ambient organic saturation concentrations, from effectively nonvolatile material at 0.01 microg m(-3) to vapor-phase effluents at 100 mg m(-3). Chemical evolution can be treated by a transformation matrix coupling the various basis vectors. Using this framework, we show that semi-volatile partitioning can be described in a self-consistent way, with realistic behavior with respect to temperature and varying organic aerosol loading. The time evolution strongly suggests that neglected oxidation of numerous "intermediate volatility" vapors (IVOCs, with saturation concentrations above approximately 1 mg m(-3)) may contribute significantly to ambient SOA formation.
一个半挥发性分配的统一框架使模型能够有效地处理半挥发性一次排放和二次有机气溶胶生成（SOA），进而处理半挥发性物质总体分布的化学演化（老化）。该框架还揭示了当前排放和SOA形成测量中的关键缺陷。这种处理方法的关键特性是一组统一的饱和蒸气压基集，其涵盖了环境有机饱和浓度范围，从0.01微克/立方米的有效非挥发性物质到100毫克/立方米的气相流出物。化学演化可以通过耦合各种基向量的变换矩阵来处理。使用这个框架，我们表明半挥发性分配可以以自洽的方式描述，在温度和变化的有机气溶胶负荷方面具有现实行为。时间演化强烈表明，许多“中等挥发性”蒸气（IVOCs，饱和浓度高于约1毫克/立方米）被忽视的氧化可能对环境SOA的形成有显著贡献。
