vt cooling

Bill C Hutton (wchutt@alex.monsanto.com)
Tue, 17 May 94 15:48:33 CDT

We also use the Neslab solution. We do not need extreme cold for our
work. We have run a protein for about a week at 4C using a Neslab cold
finger immersed in isopropyl alcohol (Unity 500). Nothing ices up. The
entire spectrometer (and lot of other stuff) runs on liquid nitrogen
boil off from a three story tank outside the building. This nitrogen is
apparently dry enough as is. Neslab made us a very long cold finger
(about 12 feet) so the refigerator unit can be well removed from the
magnet. We have never been disapointed with this set up.

Advantages: inexpensive, no vibrations, existing probe plumbing is not
modified, stable for very long periods of unattended operation

Disadvantages: limited low temperature ability (probably not useful for
< 30 deg C), takes quite a while to equilibrate, some units could be
too close to the magnet for comfort, requires liquid medium

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W.C. Hutton, Monsanto Company, Corporate Research

wchutt@monsanto.com, 314 537 6021

This message does not necessarily reflect the views of Monsanto Company
or, now that I think of it, anyone else.

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