We've just taken delivery of a Micromass IRMS with CF interfaced EA.
Micromass seem to have changed their protocol from the system Bill Showers
described.

The two peaks are time separated in a GC column and different tunings are
loaded each time.   CO2 is optimised not detuned.   A reference gas box
sends pulses of CO2 & N2 reference gases before & after each sample.  For
samples with large C/N ratios,  a diluter arrangement is used on the CO2.

We've only had the system a few weeks so I can't  make any meaningful
comment on the merits of the system.

Regards

Joe Cali


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Joseph A. Cali                    |                               |
Environmental Geochemistry Group  |                               |
Research School of Earth Sciences | Phone :  +61 2 6249 3246      |
Australian National University    |   Fax :  +61 2 6249 3683      |
Canberra, Australia,  0200        | Email :  [log in to unmask]  |
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From 1st Jan  -  1st July, 1998.
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