Hi,
Everyone,
We are using Isoprime IRMS to run CO2 samples
in DI mode. After the ion source was cleaned, we run background scan (Nupro
Valve Closed), the N2 signal is ~12 e-12, it is much higher than before
(0.8 e-12) and above the acceptable value (5 e-12). However, the
other signals, such as H2O, O2, Ar, are not excess of their maximum
acceptable values.
And to our experience, if there is a leak, Ar and H2O
would show a higher than normal background. Does anyone know what else
may be causing the high N2 background if it is not the leak? Any suggestion
would be greatly appreciated.
Wendy
Zhang
Air Quality Research Division
Environment Canada
4905 Dufferin
Street
Toronto, Ontario M3H 5T4
Tel: (416) 739-5792 (office)
Tel: (416)
739-5822 (lab)
Fax: (416)
739-4664
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