Figure 1.

Absolute VOC concentration determination with PTR-TOF-MS. Predicted and measured decrease of alpha-pinene concentrations in a flowtube along with the production of the dominant first order generation product pinonaldehyde upon exposure to ozone. Comparison between model prediction (solid lines) of mixing ratios for alpha-pinene (blue) and pinonaldehyde (red) and measured values by PTR-ToF-MS using Equation 4 (squares) showing an agreement within 10%. Reprinted with permission from ref [23]. Copyright 2012 American Chemical Society.