Hi all,
since a verz long time I fight with the magnetic field homogeneity of
a 500 Mhz magnet. In principle the magnet gives a very good resolution,
but the magnet is very sensitive against cryogen filling and even against
slight air movements in the room. The coil of the magnet is attached
by two tubes.
Now I observed, that there is a significant difference in magnet
field homogeneity, whether i have one or two nitrogen outlets
(alltogether there are three) open. If i have only one outlet
open and open the seconds one, the homogeneity decreases very
rapidly ( 1 ... 2 minutes). If I close the second outlet the old homogeneity
comes back during a time of about 30 minutes.
Did anybody observed a similar behaviour?
Hope, my question is understandable in spite of my bad english.
PS: Concerning my VNC question i continue to fight with the color
mode of XWIN-NMR and have no final solution. I got some very helpful
hints and will summarize my experience as soon as i have a working
solution.
Rainer
Received on Thu May 17 2001 - 12:57:18 MST