Fifteen heavy-duty diesel vehicles were tested on chassis dynamometer by using typical heavy
duty driving cycle and fuel economy cycle. The air from the exhaust was sampled by 2,4-
dinitrophenyhydrazine cartridge and 23 carbonyl compounds were analyzed by high performance
liquid chromatography. The average emission factor of carbonyls was 97.2 mg/km, higher than that
of light-duty diesel vehicles and gasoline-powered vehicles