Analysis of Polycyclic Aromatic Hydrocarbons in Ambient Aerosols by Using One-Dimensional and Comprehensive Two-Dimensional Gas Chromatography Combined with Mass Spectrometric Method: A Comparative Study

Table 2

GC-qMS and GC×GC-TOFMS operating conditions.

Parameters	GC-qMS	GC×GC-TOFMS
Injector settings
Injection volume	1 μL	1 μL
Inlet mode	Splitless	Splitless
Carrier gas	He (99.999%)	He (99.999%)
Carrier gas flow	1.0 mL·min^−1	1.3 mL·min^−1
Inlet temperature	280°C	300°C
GC oven temperature
Initial temperature	1 min at 60°C	1 min at 60°C
First rate	6°C/min to 310°C	6°C/min to 300°C
Isothermal pause	15 min at 310°C	15 min at 300°C
2nd oven temperature offset	—	5°C, relative to the 2nd oven temperature
Modulator
Modulator temperature offset	—	15°C, relative to the 2nd oven temperature
Modulator period	—	4.00 s
Hot pulse time	—	1.00 s
Cool time between stages	—	1.40 s
MS
Mass range	40∼550	40∼550
Electron energy	70 eV	70 eV
Ion source temperature	230°C	230°C