Optoacoustic measurements of diesel particulate emissions

Abstract
Infrared absorption by acetylene and diesel smoke particles was measured using a differential optoacoustic cell driven by a 3.4‐W CO2 laser. Real‐time particle mass concentration measurements are demonstrated. In addition we found the average particle extinction cross sections per unit mass of acetylene and diesel smoke were 0.94±0.1 m2/g and 0.83±0.2 m2/g, respectively, at the 10.6‐μm wavelength.