liquid into small bubbles. Another reason is that strong tensile
stress in the fluid "tear" into a hollow, referred to as
cavitation. Hole for the liquid vapor or another gas dissolved in
the liquid, and perhaps even a vacuum. Because of small bubbles
formed by the cavitation will vary with the vibration of the
surrounding medium constant motion, grew up, or suddenly burst.
Burst suddenly stormed the fluid surrounding the air bubble
produced by high temperature and high pressure, at the same time
produces a shock wave. Internal friction can form accompanied by
cavitation effect charge, and luminescence phenomenon resulting
from the internal discharge in bubbles. In a liquid ultrasonic
processing technology are related to the cavitation.
(3) heat effect. Due to the ultrasonic frequency is high, energy is
large, when absorbed by the medium can have a significant
effect.
4. Chemistry. The role of ultrasound can make or speed up certain
chemical reactions happen. For example, the pure distilled water
after ultrasonic treatment produce hydrogen peroxide; Is dissolved
nitrogen in the water after ultrasonic treatment produce nitrite;
Dye in aqueous solution after ultrasonic treatment can change color
or fade. These phenomena occurred always accompanied with
cavitation. Ultrasound can also accelerate the hydrolysis of many
chemicals, decomposition and polymerization process. Ultrasonic
light chemical and electrochemical process has obvious influence.
Various amino acids and other organic material solution after
ultrasonic treatment, the characteristic absorption spectrum band
disappeared and general absorption of homogeneously, this shows
that the cavitation effect makes the molecular structure has
changed. skype
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