“…The on-road vehicle emissions were calculated by EF and activity data at the city level. In the present study, the vehicle emission inventories of CO, NOx, SO 2 , NH 3 , VOCs, PM 2.5 , PM 10 , BC, and OC were calculated using the following Equation (1) [ 7 , 27 , 28 , 29 , 30 ], which was fit for evaporative emissions and operational emissions: where E is the annual emissions (t/a) of CO, NOx, SO 2 , NH 3 , VOCs, PM 2.5 , PM 10 , BC, and OC; P is vehicle population; EF is the emission factor, in grams of pollutant per unit distance for each single vehicle in g/km; VKT is the annual vehicle kilometres travelled, obtained from the GEI [ 26 ]; and j represents the national vehicular emission limit standard (Pre-China 1, China 1, China 2, China 2, China 3, China 4, and China 5 emission standards). i is the vehicle type, including 12 diesel vehicles (heavy-duty DTs, medium-duty DTs, light-duty DTs, mini diesel trucks (MDTs), DTCs, low-speed DTs, heavy-duty DVs, medium-duty DVs, medium-duty passenger vehicles (MDPV), small DVs, diesel taxis, and diesel buses), 12 gasoline vehicles (heavy-duty GTs, medium-duty GTs, light-duty GTs, mini GTs, heavy-duty GVs, medium-duty GVs, small GVs, mini GVs, gasoline taxis, gasoline buses, normal gasoline motorcycles, and light gasoline motorcycles), and nine OF type vehicles, (OF buses, OF taxis, OF HDTs, OF medium-duty trucks, OF light-duty trucks, OF heavy-duty vehicles, OF medium-duty vehicles, OF small passenger vehicles, and OF mini passenger vehicles).…”