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This is a diffusion pump system. I do not believed 44 is associated with the pump fluid? I know it has not been changed in years, so I am trying to talk myself into it.
Any ideas?
Discussions about GC-MS, LC-MS, LC-FTIR, and other "coupled" analytical techniques.
Yama001 wrote:
I have another 5972 that has always plagued the operator with high 44 background, that will recede after several days of pumping down. I am fairly convinced this is not a leak (carbon dioxide), as we do not see associated 28, 32, or 40 ions. We do not see this on other instruments on the same gas line, so I doubt it is the tank.
This is a diffusion pump system. I do not believed 44 is associated with the pump fluid? I know it has not been changed in years, so I am trying to talk myself into it.
Any ideas?
mckrause wrote:
This is a common problem with graphite ferrules. Never completely understood why, but we would see 44 (CO2) if we overtightened the graphite ferrule at the MS interface. Switched to aluminum ferrules and all of the problem went away.
Do they perform as promised, e.g no re-tightening, more leak-free?
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