We are in the process of upgrading our old (old!) AM-500. An
important use of this instrument and our AM-360 is running
experiments very cold. We routinely run spectra below -80C,
and do a reasonable number of experiments below -120C (one
group takes data regularly at -150C on our AM-360).
I am hoping you can help our evaluation of how new probes hold
up to running at lower temperatures. I am particularly
interested in how newer Bruker, Nalorac and Varian probes work
in your lab, for those of you that run at such low temps.
If you do run at low temps, please let me know your experiences:
amount of probe repair required, accuracy of thermocouple (our
AM's are quite poor here, being 15 to 20 degrees off at the
lowest temps and calibration quite sensitive to flow rate), etc.
Please also let me know if you have had negative experiences,
such as trying to go below -120C, but caps froze or wouldn't
work.
If you would make sure to specify your equipment type and age
that would help.
I will provide a summary of responses.
Thanks,
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Charlie Fry Tel: (608)262-3182
Director, MR Facility Fax: (608)262-0381
Chem. Dept., Univ. Wisconsin
Madison, WI 53706 USA email: fry@chem.wisc.edu
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