Physicochemical Characterization of Particulate Emissions from a Compression Ignition Engine Employing Two Injection Technologies and Three Fuels N. C. Surawski B. Miljevic G. A. Ayoko B. A. Roberts S. Elbagir K. E. Fairfull-Smith S. E. Bottle Z. D. Ristovski 10.1021/es200388f.s001 https://acs.figshare.com/articles/journal_contribution/Physicochemical_Characterization_of_Particulate_Emissions_from_a_Compression_Ignition_Engine_Employing_Two_Injection_Technologies_and_Three_Fuels/2634883 Alternative fuels and injection technologies are a necessary component of particulate emission reduction strategies for compression ignition engines. Consequently, this study undertakes a physicochemical characterization of diesel particulate matter (DPM) for engines equipped with alternative injection technologies (direct injection and common rail) and alternative fuels (ultra low sulfur diesel, a 20% biodiesel blend, and a synthetic diesel). Particle physical properties were addressed by measuring particle number size distributions, and particle chemical properties were addressed by measuring polycyclic aromatic hydrocarbons (PAHs) and reactive oxygen species (ROS). Particle volatility was determined by passing the polydisperse size distribution through a thermodenuder set to 300 °C. The results from this study, conducted over a four point test cycle, showed that both fuel type and injection technology have an impact on particle emissions, but injection technology was the more important factor. Significant particle number emission (54%–84%) reductions were achieved at half load operation (1% increase–43% decrease at full load) with the common rail injection system; however, the particles had a significantly higher PAH fraction (by a factor of 2 to 4) and ROS concentrations (by a factor of 6 to 16) both expressed on a test-cycle averaged basis. The results of this study have significant implications for the health effects of DPM emissions from both direct injection and common rail engines utilizing various alternative fuels. 2011-07-01 00:00:00 compression ignition engines PAH factor particle chemical properties emission reduction strategies polydisperse size distribution diesel ROS reactive oxygen species injection technology alternative injection technologies particle number size distributions point test cycle DPM Compression Ignition Engine Employing alternative fuels rail injection system