Thanks to all who replied. I punched holes in the insulation and did a
test run with the insulation and without the Kel-F. The results are
better but still not as good as they should be.
I think the next thing to work on is the timings. I didn't believe the
timings in the manual (eg capillary transfer time = 15sec) and they were
not what was set in the parameter files when I took over running the
machine. Recently I've been wondering whether some of the pumping and
transfer times are too long. The reason is that sometimes at the end of
a run the hoko beads are up the side of the vial, which I interpret as
being due to the water boiling (at 40 degrees) when the vial is
evacuated for the hydrogen fill. So what sort of times do people allow
for (1) the pumping out of a vial, (2) the hydrogen fill (I have the
regulator set to 1 atm.), (3) the transfer of hydrogen to the water trap
and (4) the drying time?
I equilibrate at 40degrees for 1.5hrs. Is that correct?
Lastly, I've had a look at the Labco site and can't see any vials which
would fit my multiprep. Am I missing something?
School of Earth and Environmental Sciences
University of Wollongong,
Wollongong, 2522, NSW
Phone 02 4221 4586 (office)
02 4226 5903 (lab)
Fax 02 4221 4250
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'Oh no, we won't give in,
we'll go living in the past'