Raman spectra are sensitive to nanocrystallite graphite and
amorphous portions of carbon which are closely related to PM oxidation
behaviour and thermal kinetics. In the present study, PM
emitted by a diesel engine equipped with a NTP reactor was sampled
at different engine loads. The differences in Raman parameters
of PM samples and their changes during oxidation were
investigated. The correlations of Raman parameters with oxidation
behaviours and thermal kinetics were also analysed. The following
results have been obtained: