2.7.3. GC–MS analysis
Around 0.1 g of oil sample was mixed with 5 mL hexane, and
the mixture was vigorously shaken by hand until no semi-solid
state oil can be observed. Afterwards the mixture was allowed to
stand still for 24 h, and the 1 L of the upper layer was injected into
an Agilent 6890 GC coupled with a 5973N MSD. The conditions of
the GC–MS were as follows: injector, 300 ◦C splitless; carrier gas,
helium 1 mL min−1; column, DB-5 ms; oven temperature program,
50 ◦C for 2 min, 45 ◦C/min to 140 ◦C, 10 ◦C/min to 300 ◦C, hold for
6 min, total run time per sample 26 min.