1. Atmospheric Environment 37 (2003) 4747–4755Atmospheric Environment 37 (2003) 4747–4755

2. Octane-enhancing gasoline additive Enhancing the combustion efficiency 1996, U.S Santa Monica contamination Reduce CO 、 Hydrocarbons 、 O 3 Reduce possibility of explosion

4. Quick diagnosis for emission source X Y Y - X Y

5.  Site I : Hsinchu, Guangfu Rd.  Site II : Hsinchu, Baoshan Rd.  Site III : Kaushiung city

6. 濃縮分離偵測 (a) (b) Trap volume 190 ml

7. PLOT DB-1 FID MS scan range 10-180

8. GC-FID 1.Ethtane 2.Ethylene 3.Propane 4.Propene 5.Ethyne 6.Isobutane 7.n-butane

9. 1.Isobutane 2.Isopentane 3.MTBE 4.2-methylpentane 5.Benzene 6.Toluene 7.Ethylbenzene 8.m,p-xylene 9.Styrene 10.o-xylene 11.1,2,4-trimethylbenzene GC/MS

10. Standard TIC real sample TIC real sample SIM

14. NMHCs/MTBESite ISite II Ethene4.74.9 Benzene1.0 Toluene4.44.9 Ethylbenzene0.90.8 o-Xylene1.41.1

16. Chemical removal : photochemical reaction Physical removal : wet deposition

18. Analytical system was established to measure VOCs and MTBE simultaneously without interference from water. In urban areas, MTBE was highly correlated with most VOCs. Using VOCs/MTBE can quickly diagnosis VOCs emissions source. MTBE can be a useful exclusive indicator of traffic emissions.