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- Posts: 5
- Joined: Mon Jun 25, 2018 10:36 pm
Has anyone seen anything like this? These are post-maintenance runs with the needle removed to check baseline. Full scan 35-500, with threshold at 100.
System specs:
Agilent 6890N with 5975 iMSD
inlet: split liner (changed every 300 injections) with 20:1 split, new septa, 250'C
column/oven: constant flow @ 1ml, DB-1MS (newly installed and conditioned at 325'C for 2.5 hours after air/water passed), 150'C initial temp, hold 1 min, with 21'C/min ramp to 276'C and hold, post run ramp to 325'C for 3 min
MSD: source 230'C, quad 150'C, transfer line 230'C, baked out for 90 min following column conditioning.
Any ideas on why this is happening would be greatly appreciated!