The Influence of the Collimating Orifice on Knudsen Triple-Cell Effusion.
Abstract
A quantitative theory for vapor effusion from Knudsen triple-cells has been developed. These cells, when used in conjunction with a mass spectrometer, permit a direct determination of the thermodynamic activity of a binary alloy component. In conventional Knudsen effussion studies, the vapor pressure of an element in an alloy and in the pure state are determined in separate experiments and their ratio is used to compute the activity. Because of the exponential relationship between vapor pressure and temperature, even small errors in temperature reproducibility result in large errors in the calculated activities. The Knudsen triple-cell avoids these errors but is subject to other limitations that are discussed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1969
- Accession Number
- AD0863804
Entities
People
- Lawrence R. Bidwell
Organizations
- Air Force Research Laboratory