[3dem] tilt cryoEM goniometer before sample holder insertion

[Jingchuan Sun]

Hello,
Before cryoEM sample holder insertion, it is rotated 90 degree, so most
liquid N2 is poured toward user from dewar. I heard that new TEM goniometer
could be tilted before holder insertion. Anyone try it with older TEM?

I'm thinking two ways for our JEOL2010F.
1) tilt gonimeter +60 degree, insert sample holder (dewar is -30 degree),
flip airlock switch to "PUMP", after green light is on and wait for another
~5 min, turn the holder clockwise ~30 degree (now dewar is straight up),
tilt gonimeter back to +30 degree, then turn the holder clockwise another
~60 degree (now dewar is +30 degree right), and finally tilt gonimeter back
to 0 degree (now dewar is straight up).

2) tilt gonimeter +45 degree, insert sample (now dewar is -45 degreet), flip
airlock to "PUMP", after greenlight is on and wait for ~5 min, turn the
holder ~30 degree (now dewar is -15 degree left) and another ~60 degree (now
dewar is -45 degree), finally tilt gonimeter back to 0 degree.

The first method need tilt gonimeter two times at high angle, but the
holder's dewar is only rotated within 30 degree.

Anyone try it on JEOL2010F? If it works, it reduce one hazardous operation
in cryoEM.
Thanks!
Jim
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://mail.ncmir.ucsd.edu/mailman/private/3dem/attachments/20110402/b1b93cfd/attachment.html