Varian 4000 GC, Hardware Operation Manual

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5. If the volume is discolored, perform the following steps.
•
Dip a cotton swab in de-ionized water and then aluminum oxide.
•
Gently scrub any discolored areas with slurry of aluminum oxide and
water
NOTE: Do not allow the aluminum oxide to dry on the surface.
•
Repeat steps 3 and 4 on the parts cleaned with aluminum oxide
6. Repeat these steps for the EI ion volume.
7. Dry all the parts in air, or in an oven set to approximately 120 °C for 30
minutes.
Re-Assembling the CI Ion Volume
1. Line up the large holes in the holder and CI ion volume.
2. Slide the CI ion volume onto the holder.
3. Place the screw through the CI ion volume into the holder and gently tighten.
While tightening, ensure the tip of the screw remains centered in the hole in
the CI ion volume.
NOTE: Do not over tighten. Over tightening may cause the CI ion volume to
bulge and stick when moving in and out of position. Check to be sure the volume
maintains its cylindrical shape.
4. Slip the spring over the assembly.
Cleaning the Filaments and External Ion Source Block
The filaments and source block normally do not require cleaning except when
high pressure CI is performed. High pressure CI can coat the filaments with a
carbon layer that needs to be cleaned to prevent leakage currents.
To clean the source block you will need the following items:
•
Aluminum oxide
•
Cotton swabs
•
De-ionized water
•
Isopropyl Alcohol or Methanol
•
Beakers
•
Ultrasonicator
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