Wolfram and Isogeochemists:

In our lab, we use a refrigerated immersion probe to cool
acetone in small dewars from room temperature down to less
than -90 C in a few minutes, avoiding the hazards associated
with exotic solvent mixtures.  The refrigeration unit, an
RP-100-CD from Lab Plant, is portable and has proved very
reliable over several years.

Mike

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Michael Isaacs, Isotope Unit,
Postgraduate Research Institute for Sedimentology,
University of Reading,
Whiteknights, Reading RG6 6AB, UK.

Phone: +44 (0) 118 9875123 ext 7972
Fax:   +44 (0) 118 9310279
Email: [log in to unmask]
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