Gregory,

John is right about a possible leak. This could happen if you have changed
the temperature of your oven (e,g, stand by?) or if you have run salt rich
samples or sometimes with baSO4. A leak may occur in the reactor region
near the bottom part of your SiO2 inlet or at the beginning of the Cu
reduction zone. Be
shure that you use sufficient quartz wool between the WO3 and the Cu.

For running BaSO4 samples I would recommend to use V2O5 in general.

Good luck
Michael

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Dr. Michael E. Böttcher
Department of Biogeochemistry
Max-Planck-Institute for Marine Microbiology
Celsiusstr.1
D-28359 Bremen
Voice:  (+49)421-2028-632
Fax:    (+49)421-2028-580
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