In reply to some of Paul Brook's questions, the CE elemental analysers come
with a larger O2 loop as you can then control the actual volume injected using
the "Oxygen inject STOP" setting, or at least this is the case on our NA1500.
When we were using ordinary grade oxygen instead of pure grade, I was able to
measure the volume injected at various inject times by measuring the peak due
to the nitrogen impurity. For our 10ml loop I got:
40s = 10ml, 20s = 9.4ml, 10s = 6.6ml, 8s = 4.8ml and 6s = 3.7ml.
(rough measurements from chart paper with a ruler). So to do this yourself all
you need is the cheap oxygen and then to measure the size of the nitrogen
blank.
Hope this is of help.
Robert Van Hale
(Graduate Student)
Chemistry Department
University of Otago
PO Box 56
Dunedin
New Zealand
Ph (+64)(03)479 7908
Fax (+64)(03)479 7906
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