Observation of Loach's Slime Layer by CCD Microscope and Its Tribological Consideration

摘要

Loaches covered with slime as an experimental model for frictional problems was observed. The effects of slime on lubrication were not only drag reduction in flow, but protecting and lubricating for the living loach's inside soft skin on which it was hard to observe the delicate phenomena. After examination of proteoglycans, which was included in slime, observation was conducted. That was conducted by a charge-coupled device microscope in order to catch the slime aggregates and the slime layer of a living loach, in water and in saline. It was recognized that slime is a bioelectrolyte polymer. The aggregates of slime in water seemed to be cylinder-like rigid structures consist of discs. The slime layer of the loach in water was observed as piles for the same direction. This layer was recognized as being lyotropic, smectic, and discotic liquid crystal. It was considered that the living loach's inside soft skin might be contributed through the phenomena of slime on protecting to friction also to swing (as in peristalsis) and pulse (as in pulse pressure).