NMR: Difference between revisions
From Pumping Station One
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* The tube can now be placed into the instrument. Hold the eject button partway and release it slowly to allow the tube to gently fall into the probe. | * The tube can now be placed into the instrument. Hold the eject button partway and release it slowly to allow the tube to gently fall into the probe. | ||
* Use the PNMR software to capture and observe the resulting spectrum. | * Use the PNMR software to capture and observe the resulting spectrum. | ||
** Type GS and hit enter. You should see a small menu appear on the top-right and a peak should be produced. If you see a ringing wave instead, you are actually looking at the FID. Hit Control-S to switch to the spectrum. | |||
* If the NMR has not been used in a long time, and you do not see a peak from your water sample, you may need to adjust the shunt mechanically. | |||
** You will need either a long brass flathead screwdriver or a long wooden tool to turn the screw deep inside the instrument (it should more very freely with almost no resistance). | |||
** As you do this, you should see the peak move left when turning counter-clockwise, and right when turning clockwise. The goal is to keep it in the center. | |||
** Once centered, you might want to run the "shim" command to have the electronic shimming routine do the rest of the fine tuning. | |||
== Operation / Background == | == Operation / Background == | ||
