ultrahelitöötlus

Ultrahelitöötlus, also known as ultrasonic treatment or sonication, is a process that uses high-frequency sound waves to induce cavitation in a liquid medium. Cavitation is the formation, growth, and subsequent implosion of microscopic bubbles within the liquid. The implosion of these bubbles generates localized high temperatures and pressures, as well as intense shear forces and microjets.

These physical effects can be harnessed for a variety of applications. In chemistry, ultrahelitöötlus can enhance reaction rates, promote dissolution of solids, and aid in the synthesis of nanoparticles. It is also used for degassing liquids, removing dissolved gases that might interfere with subsequent processes or affect product quality.

In the food industry, sonication can be employed for extraction of compounds from plant materials, such as oils and antioxidants. It can also be used for pasteurization and sterilization, as the energy released during cavitation can disrupt microbial cell membranes. In materials science, it finds use in cleaning delicate components, dispersing nanoparticles in suspensions, and modifying material surfaces. Medical applications include therapeutic ultrasound for tissue heating and diagnostic imaging, though the term "ultrahelitöötlus" typically refers to the mechanical effects of high-intensity ultrasound. The frequency of ultrasound used typically ranges from 20 kHz to several MHz, with higher frequencies generally leading to smaller, more numerous cavitation bubbles and gentler treatment, while lower frequencies produce larger bubbles and more intense effects. The specific parameters, such as frequency, power, and treatment time, are crucial for achieving the desired outcome in each application.