Dear Tim,
I would recommend to consult B. Kornexl et al, Rap Comm Mass Spectrom.
13 (1999) 1685. High temperatures and Glassy Carbon to shield the CO
from the hot Al2O3 surface are a must.
Regards    Willi

--
‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰
Willi A. Brand, Stable Isotope Laboratory       [log in to unmask]
Max-Planck-Institute for Biogeochemistry
Tatzendpromenade 1a, 07745 Jena, Germany        Tel   +49-3641-643718
P.O.Box 100164, 07701 Jena, Germany             Fax:  +49-3641-643710
‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰‰