Insulators / 100_insulators.jpg
Insulating dewar, shown on far right, molded with hanging
clips in upper lip. Dewars are used to hold liquid nitrogen in a molecular
How Do Molecular Sieves Pump?
By the process of adsorption. This is somewhat similar to catching
flies with fly paper. When the molecular sieve is chilled to LN2
temperature, it will adsorb most air gases on its vest surface area.
Gas atoms or molecules which contact the molecular sieve will "stick."
They will not become "unstuck" until the molecular sieve becomes warmed.