Dear Andreas,

in your query to the list you mention that you are measuring the d18O
values of silicates in CF mode. This sounds like you got the solution for
18O measurement of silicates using EA-pyrolysis??? And with a SD of
something around 0.1 per mill? Quite incredible - so maybe I got something
wrong here. Could you please give some more details on your method, maybe a
reference?
Thanks

Barbara


At 11:07 17.09.1999 +0200, you wrote:
>Dear Listmembers,
>
>we´re running an Europa 20-20 MS in CF-mode for analyses of O-isotopes.
>The MS itself produces a noise signal in the range of 0.05-0.1 permil
>(18O). However, I always observe a drift over 3-4 hours in the range of
>1-2 permil. The drift is pretty linear an can be well fitted. The 1sigma
>error of drift corrected analyse of 0.3 mg silicate is between 0.12
>permil. Does anybody works with such a machine and observes this drift?
>Another problem is the poor (unfortiunalety MS-Windows-based) Europa
>software ("vanca-sl 1.99" and especially "ancrepro" evaluation
>software). If there is anybody having problems with calculation the
>results using the ancrepro-programm, he may send a mail to me. I´ve
>written a small programm (in C, which I can compile for MS-Windows and
>Linux) for the evaluation of the raw data. It produces an *csv-file
>which can be read in Excel or StarOffice,
>
>Andreas
>
>
>Dipl. Min. Andreas Pack
>Mineralogisch-Petrologisches Institut und Museum
>Poppelsdorfer Schloss
>D-53115 Bonn (Germany)
>
>
****************************************************************
Dr. Barbara E. Kornexl
UFZ - Umweltforschungzentrum Leipzig-Halle GmbH
Sektion Analytik
Permoserstr. 15
D-04318 Leipzig

Tel.:   ++49/341/235-   2252
Fax:                    2625
E-Mail: [log in to unmask]
*********************************************************************