Aftertreatment with Non-thermal Plasma Reactor Demonstrates Improved NOx Reduction: Under JE05 test conditions, average exhaust gas temperature is about 195 deg. C. Therefore, aftertreatment devices may not be fully functional to reduce exhaust gas emissions especially under low load because a specific amount of heat is required to activate the catalysts to convert toxic pollutants effectively. Urea selective catalytic reduction (SCR) is no exception, and it requires an exhaust gas temperature of about 200 deg. C at least to efficiently reduce NOx emissions. Researchers at Hino Motors and Toyohashi Technology and Science University investigated the urea SCR NOx aftertreatment system combined with non-thermal plasma for improving low-temperature performance. An experimental plasma reactor was constructed and tested with both model gas and diesel exhaust to evaluate performance of the SCR catalyst.