Greg:

This may not help much, but the American Physical Society held a meeting
recently in which the diffusivity of liquid hydrogen and some of the inert
gases was determined for porous Vycor.  See, as an example:

http://www.aps.org/BAPSMAR97/abs/S4550011.html

Steve


>As long as we are on the subject, has anybody done experiments regarding
>the retentivity of vycor vs. quartz for gases (particularly H2)?  Given
>the manufacturing characteristics of vycor that have been described, I
>would expect quartz to be less subject to H2 diffusion than vycor.
>
>cheers,
>greg
>--
>Dr. Greg B. Arehart
>Department of Geological Sciences, MS-172
>University of Nevada, Reno
>Reno, NV 89557-0138
>*****please note new area code*****
>phone: 775-784-6470
>fax: 775-784-1833
>email: [log in to unmask]


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