MODIFICATION AND OPERATION OF A KNUDSEN EFFUSION APPARATUS

摘要

Effusion vapor pressure measurements have been a source of thermodynamic data from this laboratory for some time. Con¬siderable interest exists in rare earth-alkaline earth alloy systems. The ensuing report is a summary of the progress made in modifying the Knudsen effusion apparatus first reported by Smythe and modified by others. It was felt that the 2nd and 3rd law heats of vaporization could be made to agree better than previous reports. The major objective then was to modify the effusion apparatus and check its validity with mag¬nesium. Continued measurements on rare earth-magnesium are planned.