Penny,

Have you tried baking the column?

Paul Eby
University of Victoria

At 10:55 AM 23/09/2008, you wrote:
>All,
>
>I've been writing to this list a lot lately. The mass spectrometer 
>is finally behaving properly and I am finally trying to fix a 
>problem that appeared just as everything else went crazy.
>
>When I run carbonate samples using our Gas Bench, typically it takes 
>about 300 seconds for the carbon dioxide sample peak to come out. 
>This has been the case for more than a year. Then, literally 
>overnight, this changed to about 400 seconds. Nothing on the 
>Gasbench was changed during the intervening night.
>
>Since then, I've adjusted the GC temperature, which only changes the 
>elution times by a few 10's of seconds at most. I've also adjusted 
>the Helium carrier pressure, which makes the peaks come out at the 
>right time, but the flow is so rapid that my sample peaks diminish 
>far too quickly for an adequate analysis.
>
>What am I missing?
>
>Thanks,
>
>~Penny
>
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