Thanks to all that provided references and information on molecular sieves.
I'm happy to be talked out of using an toepler pump.  I'd also appreciate
any recommendations on vendors/models of small Hg diffusion pumps to getter
F2.

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Steve Nelson
Dept. of Geology
673 WIDB
Brigham Young University
Provo. Utah  84602

voice:  1-801-378-8688
FAX:  1-801-378-8143

"INTEL INSIDE" is a warning label
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