I have been attempting to "freeze" methane into a quartz ampule without
success. Samples are classified as dry methane, however I have been
freezing out any remaining water with the standard dry ice/methanol mix.
Raw sample pressures vary between 50-300psi, yet the silica gel technique
has not been friendly. I cannot seem to find any guiding publications for
the method; can anyone point me in the direction of such a paper?

Here is what is in the quartz ampules.  1g CuO and 20 2mm silica beads. I
cooked the beads for 4 hours at 400C to clense the nucleation sites, and
the CuO is clean. Am I not using the right amount of beads? Anyone have
similar problems? I appreciate any contributing thought that will aide
progress.  Cheers.

Aaron Laubhan
University of Arkansas
113 Ozark Hall
Fayetteville, AR 72701
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