fibrillation

fibrillation

1. a local and uncontrollable twitching of muscle fibres, esp of the heart, not affecting the entire muscle. Atrial fibrillation results in rapid and irregular heart and pulse rate. In ventricular fibrillation, the heart stops beating

2. irregular twitchings of the muscular wall of the heart, often interfering with the normal rhythmic contractions

Fibrillation

 

the destruction by mechanical action of the bonds between the tiny fibers (fibrils and microfibrils) making up the cell walls of plant fibers and the penetration by water of the space between the fibrils.

Fibrillation may occur both on the surface of and within the cell wall of the fibers. With surficial fibrillation fragments of fibrils and the cell wall are separated from the fibers and form a nap on the fibers. With internal fibrillation the weakening and partial destruction of the bonds between fibrils increase the flexibility and plasticity of the fibers. Internal fibrillation enables the fibers to form bonds without losing strength. Fibrillation, the main process in beating cellulose during paper production, increases the surface of the fibers and releases the hemicelluloses inside the fibers, making it possible for the hemicelluloses to take part in the formation of bonds between fibers in the sheet of paper. The splitting of the fibrils establishes conditions for improved intertwining of fibers, increasing the mechanical strength of the paper sheet yet reducing the absorbency. Rolls, conical and disk mills, and similar devices are used for fibrillation.

REFERENCE

Ivanov, S. N. Tekhnologiia bumagi, 2nd ed. Moscow, 1970.

G. A. IVANOV

fibrillation

[‚fib·rə′lā·shən]

(physiology)

An independent, spontaneous, local twitching of muscle fibers.

(textiles)

A process in which yarn is extruded as a ribbon or a tape rather than as a fine filament.