can anyone tell me what is that weird mass 30 peak? (you can see it in the
picture here http://dl.dropbox.com/u/3191726/weird%20mass%2030%20peak).
Some useful information:
- we have a Thermo Flash 2000 EA plugged to a Delta V Advantage IRMS
- last week we run some liquid samples for 15N (samples were enriched up to
roughly 3permil) using a Thermo AI/AS3000 autosampler.
- yesterday we switched back to the solid autosampler AS200 (the run you
see in the picture is a solid acetalinide standard)
- yesterday we also changed combustion, reduction ovens and water trap
- d15N of our standards (urea and acetalinide for the moment) are perfect.
Thanks for your help