Cryo-sorption

A represents mechanical pump or steam ejector B, booster pump D, cryo, turbomolecular, sorption, ion, or trapped diffusion pumps. 

Pump-down of the antechamber, following solution experiments, involved sorption pumping and cryo-pumping resulting in the pressure decreasing from ambient to 10 Torr in 5 minutes. The resulting sample surfaces were subsequently examined by both LEFT) and AES after transfer back to the analysis-chamber. 

Bowman Jr, R.C., Ryba, E.L. and Freeman, B.D., Characterization of prototype sorption cryo coolers for periodic formation of liquid and solid hydrogen. Advances in Cryogenic Engineering, 1994, 39 p. 1499. 

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