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A one‐dimensional model of mechanical deformation of compressible chromatography columns is presented. The model is based on linear elasticity and continuum mechanics and is compared to a more complete two‐dimensional model and one‐dimensional porosity profiles measured by NMR imaging methods. The model provides a quantitative description of compression and the effects of wall support during scale‐up. A simple criterion for the significance of wall support as a function of both diameter and length is also developed. Although the model accounts only for mechanical deformation, flow compression can be included, and validation presented here suggests that a more complete model may be valuable for anticipating the effects of scale and aspect ratio on pressure‐flow behavior of compressible columns.

Balloon-borne gamma-ray detection equipment flown from Thule, Greenland, during April 1962, indicated that there was considerable radioactivity above 70,000 feet. Gamma-ray spectra obtained indicated the source of much of the activity to be the Soviet nuclear tests in late 1961.