I have been running samples lately and things are looking good. Baseline of the GC-FID is solid at 2.7 pA for the instrument background. The only exception was this morning, when I had to fix a leak on the ultra-zero air cylinder (I wonder, where that came from?), which took a while to locate. But now things are working fine, although I am in for a long evening.
I use the same water that I have used at Alert for rinsing and cleaning (except that the feed is different – I have used DI water at Alert and I now use water from our standard MilliQ system as feed, because the pre-treated water is RO, which the cartridge in the portable system is not suitable for). Water quality is fine and blanks are very similar to those in Alert.
Today I run snow samples collected on June 2 at the Special Studies Trailer (SST), snow layers from 2-6 cm and 36-53 cm from the surface. I carry out headspace and liquid phase measurements in duplicates using a divinylbenzene-coated SPME fibre.
