We have an 1100 series hewlett-packard with a diode array detector.
We sometimes see slow (period of about 5 min) oscillations in the output.
The pattern is more complex than a simple sine wave. The amplitude is
about 2 milliabsorbance units both at 220 nm and at 280 nm. It is hard to
predict when the oscillations will appear or disappear. HP thinks it could
be the lamp and has suggested turning the flow to zero and seeing what
happens, but they don't have any further suggestions.
Does anyone have any ideas about what is going on, or useful ways
to proceed?
Chris Halkides
Christopher Halkides
Dept. of Chemistry, UNCW
601 S. College Road
Wilmington, NC 28403-3297
(910) 962-7427