PARTICULATE O R G A N C MATTER I N SEA WATER
77
This interesting series of papers helps to broaden our knowledge of
surface film processes. Some of the facts they report may have a direct
bearing on problems of particle formation. There is a possible mechanism here for fractionation of materials and for concentration of the
carbohydrate and protein components, which appear to be particularly
important in flake formation. These authors presumably were thinking
of downward displacement of the less surface-active materials. However, it is equally possible that water droplets derived from bursting
bubbles and carrying the usual array of surface film organics and inorganic ions could, when they fall back into the sea, release the most
surface-active molecules to the interface and leave the other substances
floating on a ‘‘ dry ” surface. Such phenomena could be involved in
the kind of flake formation described by Wangeraky (1965).
Other investigators, cited in an early section of the paper, thought
that particulate matter formed as little skins of organic matter on
submerged bubbles. This is a distinct possibility ; flakes can form very
quickly. The writer has collected flakes by holding a microscope slide
over filtered sea water, turning on an air supply, and removing the
slide as soon as it collected a few droplets. Typical flakes could be seen,
sometimes still adhering to intact bubbles.
Several investigators have mentioned the fact that bubbles can
scavenge bacteria and nanoplankton as well as non-living particles.
These materials have been shown to accelerate flake formation and
presumably are incorporated within them. However, there is little
visible evidence of this. The flakes are not a mere conglomeration of
small particles. Enough other materials have been added to give them
a emooth surface and essentially homogeneous appearance. This
implies additional adsorption of colloids and/or polar molecules. The
impermeable nature of the material formed and the presence of molecules of high molecular weight suggests that synthesis is occurring.
Electrical charges at air-water interfaces are an obvious source of
energy for organic synthesis. If these are the main factors involved,
then the various sites and modes of formation mentioned above are
not mutually exclusive.
I n contrast with the flakes, most of the particles that form spontaneously in filtered water have a granular appearance, suggesting that
they are merely an aggregation of discrete smaller particles, and as
indicated earlier their reactions to histochemical stains are also different.
However, some flakes are invariably found in these experiments on
in situ aggregation. The most careful precautions to eliminate airwater interfaces during and after filtration do not entirely prevent their
formation. Moreover, there is circumstantial evidence that they are
77
This interesting series of papers helps to broaden our knowledge of
surface film processes. Some of the facts they report may have a direct
bearing on problems of particle formation. There is a possible mechanism here for fractionation of materials and for concentration of the
carbohydrate and protein components, which appear to be particularly
important in flake formation. These authors presumably were thinking
of downward displacement of the less surface-active materials. However, it is equally possible that water droplets derived from bursting
bubbles and carrying the usual array of surface film organics and inorganic ions could, when they fall back into the sea, release the most
surface-active molecules to the interface and leave the other substances
floating on a ‘‘ dry ” surface. Such phenomena could be involved in
the kind of flake formation described by Wangeraky (1965).
Other investigators, cited in an early section of the paper, thought
that particulate matter formed as little skins of organic matter on
submerged bubbles. This is a distinct possibility ; flakes can form very
quickly. The writer has collected flakes by holding a microscope slide
over filtered sea water, turning on an air supply, and removing the
slide as soon as it collected a few droplets. Typical flakes could be seen,
sometimes still adhering to intact bubbles.
Several investigators have mentioned the fact that bubbles can
scavenge bacteria and nanoplankton as well as non-living particles.
These materials have been shown to accelerate flake formation and
presumably are incorporated within them. However, there is little
visible evidence of this. The flakes are not a mere conglomeration of
small particles. Enough other materials have been added to give them
a emooth surface and essentially homogeneous appearance. This
implies additional adsorption of colloids and/or polar molecules. The
impermeable nature of the material formed and the presence of molecules of high molecular weight suggests that synthesis is occurring.
Electrical charges at air-water interfaces are an obvious source of
energy for organic synthesis. If these are the main factors involved,
then the various sites and modes of formation mentioned above are
not mutually exclusive.
I n contrast with the flakes, most of the particles that form spontaneously in filtered water have a granular appearance, suggesting that
they are merely an aggregation of discrete smaller particles, and as
indicated earlier their reactions to histochemical stains are also different.
However, some flakes are invariably found in these experiments on
in situ aggregation. The most careful precautions to eliminate airwater interfaces during and after filtration do not entirely prevent their
formation. Moreover, there is circumstantial evidence that they are