Dear Friends,

Does anyone of you have an idea on the long term stability (i.e. 1-2 years)
of the delta value of certified gas tanks provided by the German factory
Messer Griesheim ?
I have recently performed analysis of intercomparison materials (IAEA-CO1 &
CO9) against the M. G. CO2 tank attached (since 1.5 yr) to my MS, and found
a shift of about 1 permil with respect to originally certified value.
Thanks for advices or comments.

Pat

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Patrick DAUBY
Universite de Liege
Laboratoire d'Oceanologie
Unite de Recherche en Biogeochimie des Isotopes Stables (URBIS)
B6 Sart Tilman
B-4000 Liege, Belgium
Phone: +32.4.3663322
Fax: +32.4.3663325
WWW: http://www.ulg.ac.be/oceanbio/urbis.htm
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