Dear list members,

 I'm planning mass spectrometric measurement of oxygen isotope ratio on pure
 oxygen with Finigan MAT252. Dr. Meijer's comment on ionization efficiency o
f molecular oxygen was interesting to me.  But I wonder if there are ploblem
s associated with introducing O2 directly to the inlet of MS, such as adsorp
tion, fractionation, damage to the filament and so on.
 Would anyone give me some information (published literatures are also helpf
ul) about this?

Thanks in advance,



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Dr. Sakae TOYODA
Postdoctoral researcher of Japan Science and Technology Corporation
Department of Environmental Science and Technology
Tokyo Institute of Technology
4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
Phone +81-45-924-5517
Fax +81-45-924-5519
E-mail: [log in to unmask]
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