Chromatographic separation was
achieved using a GC column (RTx-5, 30m×0.32mm
i.d. 0.25m film thickness, Restex, USA). GC conditions
were as follows: 99.99% as the carrier gas, pressure
of 15 psi, initial column temperature of 40 ◦C was held
for 3 min, an oven ramp rate of 10 ◦C/min to 200 ◦C and
ramp rate of 50 ◦C/min to 280 ◦C