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| Physical, Chemical and Biological effects of sound
? Can sound alone produce effects ?
The answer is yes. Particularly for high frequency sound, at extremely high levels. Such sound is usually borne by liquids. And such sound actually modifies the liquid through which it is passing. For instance, at these high levels the water molecule is actually severed into H, OH pairs in a process known as cavitation. Most of these pairs immediately recombine into water again, emitting light in a process known as sonoluminescence. An emerging technology which uses these effects in various chemical solutions is known as sonochemistry. An example of a physical effect is heating. In our laboratory we regularly expose Plexiglas plastic to thousand-watt bursts of ultrasound by holding the Plexiglas in front of a transducer. The result is that the plastic actually melts underwater, while the water remains cool. Another physical effect is particle size reduction: exposure of some nanoparticles to high levels of sound will break them into yet smaller particles. An example of a biological effect is sterilization. Almost all microscopic plants and animals die if exposed to high intensity sound in the frequency range of 500 kHz to one megahertz. This fact is currently being investigated as an alternative, safe way to purify what you eat and drink. High frequency ultrasound is the "microwave" of sound. The wavelength of the older, more conventional twenty kilohertz ultrasound is 7.5 cm. The typical frequency we use is 660 kilohertz, which has a wavelength of 2.2 millimeter. These higher frequencies allow higher ultrasonic energy densities of several hundred watts per square centimeter. Our mission at Ultrasonic Energy Systems is to provide researchers with the hardware necessary to explore all the physical, chemical and biological effects of ultrasound. And to provide follow-on support and hardware for the result of those studies, when larger or more specific systems are required. Thank you for visiting our site !
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