Differential Photoacoustic Particle Absorption Monitor, Phase II

We developed a highly sensitive and compact instrument to directly measure particulate matter (PM) optical absorption. This device is based on differential photoacoustic absorption spectroscopy (DPAS) technique, which is capable of eliminating background interference from gaseous NO2 and engine acoustic noise. This method significantly improves detection sensitivity compared to the single-cell photoacoustic technique. Over the currently used filter-based measurement techniques, it has the following technical advantages: 1) Direct PM absorption detection 2) Real-time measurement system 3) Low background noise 4) Low-cost commercial components More »