Charcoal as a Helium Cryopump: Version 1.0
نویسنده
چکیده
Sedgley et al [1] studied several different types of charcoal, including those derived from coconut, coal, hardwood, and petroleum byproducts. The charcoal with the best pumping characteristics (speed and capacity) was PCB coconut charcoal, US mesh size 12x30 (granule size 0.6-1.7 mm). This type of charcoal did not have the largest overall surface area (per volume), despite what one might expect about pumping ability being correlated mainly to surface characteristics.
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