Real-time measurement of peroxyacetyl nitrate using selected ion flow tube mass spectrometry.

The on-line detection of gaseous peroxyacetyl nitrate (PAN) using selected ion flow tube mass spectrometry (SIFT-MS) has been investigated using a synthetic sample of PAN in air at a humidity of approximately 30%. Using the H(3)O(+) reagent ion, signals due to PAN at m/z 122, 77 and 95 have been identified. These correspond to protonated PAN, protonated peractetic acid and its water cluster, respectively.

Simulating organic aerosol formation during the photooxidation of toluene/NOx mixtures: comparing the equilibrium and kinetic assumption.

Organic compounds contribute an appreciable mass to particulate matter and thus impact the hygroscopic and radiative properties of an aerosol distribution. Being able to predict the chemical and physical properties of aerosols based on their size and composition is critical to assessing their impact on air quality, visibility, and climate change. In this study, a comparison was performed between an equilibrium and a kinetic model for simulating organic aerosol formation during the photooxidation of toluene/NO/isopropyl nitrite mixtures.