Last updated 10/29/2020
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7.
Wait for 2 minute airlock pump time to count down.
8.
After airlock pump time complete, “reset” the alpha value WITH HANDS ON THE DEWAR OF
THE HOLDER so that the holder remains stationary
a.
The stage should rotate back to 0 degrees while the holder top is still at 3 o’clock
position.
9.
Slowly turn holder counter-clockwise to from the 3
o’clock to the 12 o’clock position while watching IGP1
a.
If you see a spike in IGP1, stop rotation and wait
until the IGP1 value recovers (at least 2 values
down OR until the cartoon diagram in vacuum
overview is in the cyan region; see image)
b.
Your goal should be to insert the holder from the 3
to 12 o’clock position within ~
1 MINUTE.
The
longer the insertion takes, the greater chance you
have of crashing the vacuum.
10.
Once at the 12 o’clock position, gently apply resistance on
the holder (away from the column) and slowly let the
vacuum of the scope pull the holder in.
a.
Give the dewar a slight rotational jiggle to ensure
the holder is inserted all the way into the column.
11.
Top off cryo holder dewar with LN
2
once inserted.
12.
Ensure that “High Tension” and “Operate” are still yellow (did you crash the vacuum? Will be
grey if vacuum crashed.)
13.
Turn turbo pump off.
14.
Do not open the column valves until IGP1/Column < 10. If you are ever in doubt, close the
column valves and contact an EMG staff member immediately.
Room Temperature Holder Insertion:
1.
Make sure IGP1 < 20, High Tension ON, column valves closed, reset holder, objective aperture
out, flu screen down.
2.
Check that the airlock default pump time is >120 sec (can go as low as 30 sec).
a.
Setup → settings
3.
Insert holder with bearing pin lined up at 5 o’clock position (there is a white line marked on the
purple plate). Stabilize the holder until the airlock pumping time of 2 minutes shows up in the
Vacuum Overview window.
4.
Select ‘Single Tilt Holder’ as specimen holder.
5.
Wait for 2 minute airlock pump time to count down.
6.
After airlock pump time is complete, slowly turn holder counter-clockwise so that the holder
selection pin moves from the 11 o’clock to the 6 o’clock position. Keep a close eye on IGP1 for
spikes; if you see a sharp increase in IGP1, then SLOW DOWN
7.
Once at the 12 o’clock position, gently apply resistance on the holder (away from scope) and
slowly let the vacuum of the scope pull the holder in.
a.
Give the dewar a slight jiggle to ensure the holder is inserted all the way into the column.
Содержание TF20
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