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In order to understand aging processing of organic aerosols (OA), one intensive field campaign was conducted during the season of spring monsoon at a receptor site (Changdao Island) in the North China. A high resolution time-of-flight aerosol mass spectrometer (HR-tof-AMS) was applied to measure mass concentrations and major chemical compositions of submicron particles (PM1). The organic aerosols are the major compositions of PM1 (30. 2%), followed by nitrate (27. 7%), sulfate (18. 8%), ammonium (14. 7%), black carbon (5. 6%), and chloride (3. 0%) with the PM1 concentration of 47. 1±36. 4 μg m- 3 during the campaign. Four organic aerosol components from the high resolution organic mass spectra were resolved by Positive Matrix Factorization (PMF), including low-volatility oxygenated organic aerosol (LVOOA), semi-volatile oxygenated OA (SV-OOA), hydrocarbon-like OA (HOA) and a firstly resolved coal combustion OA (CCOA). The average elemental ratio of oxygen to carbon (O/C) at Changdao is 0. 59, which is comparable to oxygenated organic aerosol (OOA) in other field studies reported, indicating the heavily oxidized OA during the campaign. To investigate oxidation reaction mechanisms for organic aerosols, Van Krevelen diagram (H/C vs. O/C) was utilized. The evolutions of OA elemental compositions in Van Krevelen diagram show a slope of -0. 63, however, the OA influenced by coal exihibte a totally different way. The aging of organic aerosols associated with photochemical age was investigated. It is shown that OA/ΔCO, as well as LV-OOA/ΔCO and SV-OOA/ΔCO, positively correlated with photochemical age. LV-OOA accounted for 73% of the OA secondary formation in the oldest plumes (photochemical age of 55 hours). The OH rate constant (kOH) of OA precursor to form SOA was calculated by fitting the O/C ratio with photochemical age. The value of kOH calculated is 9. 1×10-12 cm3 molcule-1s-1 at Changdao, indicating that SOA formation in Changdao is more depending on anthropogenic VOCs other than biogenic VOCs. The kOH in this study can be used as reference parameter to simulate SOA in China.