Adsorption of Surface-Active Material at the Sea/Air Interface

摘要

The concentration of soluble, surface-active, organic matter in the ocean will vary with time and location. In general, sufficient surface-active material will be present to provide closely packed films at the surface under favorable conditions. The rates of adsorption of the surface-active material at a sea/air interface were studied by measuring surface tension and surface potential as a function of time. The sea water samples studied were from the ocean near La Jolla, California. Surface potential measurements indicated that adsorption of surface-active material began immediately after the interface was cleaned; however, a noticeable decrease in surface tension was not observed until the water surface was covered with a continuous film of surface-active material. Between 10 and 60 minutes were usually required to give a film having a film pressure of a few tenths of a dyne/cm, the minimum film pressure normally associated with the damping of capillary waves. Changes in surface potential and surface tension were also determined as functions of the degree of compression of the adsorbed material. (Author)