An aerosol flow tube study of the interaction of N_2O_5 with calcite, Arizona dust and quartz

摘要

The interaction of N_2O_5 with dispersed samples of Arizona Test Dust (ATD), Calcite (CaCO_3) and quartz (SiO_2) was investigated at varying relative humidity using an aerosol flow reactor. Reactive uptake coefficients, γ. obtained at close to zero relative humidity were (4.8 ± 0.7) × 10~(-3) for CaCO_3, (8.6 ± 0.6) × 10~(-3) for Quartz and (9.8 ± 1.0) × 10~(-3) for ATD. In the case of calcite, evidence was obtained for an enhanced rate of uptake at relative humidities above ≈ 50%. The results are compared to literature values obtained using bulk substrates and to previous aerosol uptake data on Saharan dust.