Ultrasonics

Ultrasonics

"Ultrasonics" is a trade term coined by the Ultrasonic Manufacturers Association and used by its successor, the Ultrasonic Industry Association, to refer to the use of high-intensity acoustic energy to change materials. This usage is contrasted to "ultrasound", which is generally reserved for imaging, as in sonar, materials examination (NDI), and diagnostics (mammography, doppler bloodflow, etc.). However, in spite of this distinction, much technical material on ultrasound imaging actually uses the term ultrasonics, for example
* "Ultrasonic Flaw Detection for Technicians", 3rd ed., 2004 by J. C. Drury
* "Ultrasonic nondestructive evaluation : engineering and biological material characterization", Boca Raton, FL : CRC Press, c2004, by Tribikram Kundu

Ultrasonication offers great potential in the processing of liquids and slurries, by improving the mixing and chemical reactions in various applications and industries. Ultrasonication generates alternating low-pressure and high-pressure waves in liquids, leading to the formation and violent collapse of small vacuum bubbles. This phenomenon is termed cavitation and causes high speed impinging liquid jets and strong hydrodynamic shear-forces. These effects are used for the deagglomeration and milling of micrometre and nanometre-size materials as well as for the disintegration of cells or the mixing of reactants. In this aspect, ultrasonication is an alternative to high-speed mixers and agitator bead mills. Ultrasonic foils under the moving wire in a paper machine will use the shock waves from the imploding bubbles to distribute the cellulose fibres more uniform in the produced paper web, which will make a stronger paper with more even surfaces, see more on [http://www.ultratechnology.se/ Ultra Technology] . Furthermore, chemical reactions benefit from the free radicals created by the cavitation as well as from the energy input and the material transfer through boundary layers. For many processes, this sonochemical (see sonochemistry) effect leads to a substantial reduction the reaction time, like in the transesterification of oil into biodiesel.Ultrasonication can easily be tested in lab scale for its effect on various liquid formulations. Within the past five years equipment manufacturers like [http://www.hielscher.com/ultrasonics/industry.htm Hielscher] developed a number of larger ultrasonic processors of up to 16 kW power. Therefore volumes from 1mL up to several hundred gallons per minute can be sonicated today in order to achieve all kinds of results from the link that is shown below.

External links

* [http://www.scs.uiuc.edu/suslick/ Kenneth S. Suslick on Chemical Effects of Ultrasonics including nano-materials synthesis and sonoluminescence]
* [http://www.ecospheretech.com/index.php/technology/ozonix-process Ultrasonics and advanced oxidation process demonstration]


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Look at other dictionaries:

  • ultrasonics — [ul΄trəsän′iks] n. the science dealing with ultrasonic phenomena …   English World dictionary

  • ultrasonics — /ul treuh son iks/, n. (used with a sing. v.) the branch of science that deals with the effects of sound waves above human perception. [1930 35; see ULTRASONIC, ICS] * * * Vibrational or stress waves in elastic media that have a frequency above… …   Universalium

  • ultrasonics — ultragarsas statusas T sritis chemija apibrėžtis Garso bangos, kurių dažnis viršija žmogaus girdos viršutinę ribą (15–20 kHz). atitikmenys: angl. supersound; ultrasonics; ultrasound rus. ультразвук …   Chemijos terminų aiškinamasis žodynas

  • ultrasonics — ultraakustika statusas T sritis fizika atitikmenys: angl. supersonics; ultra acoustics; ultrasonics vok. Ultraakustik, f; Ultraschallehre, f rus. акустика ультразвуковых частот, f; ультраакустика, f pranc. acoustique des fréquences ultrasonores,… …   Fizikos terminų žodynas

  • ultrasonics — ultragarsas statusas T sritis fizika atitikmenys: angl. supersound; ultrasonics; ultrasound vok. Ultraschall, m rus. ультразвук, m pranc. ultrason, m …   Fizikos terminų žodynas

  • Ultrasonics Sonochemistry —   Titre abrégé Ultrason. Sonochem. Discipline Chimie Langue Anglais Directeur d …   Wikipédia en Français

  • ultrasonics — noun plural Date: 1924 1. ultrasonic vibrations or compressional waves 2. singular in construction the study of ultrasonic vibrations and their associated phenomena 3. ultrasonic devices …   New Collegiate Dictionary

  • ultrasonics — noun the science and technology of ultrasound …   Wiktionary

  • ultrasonics — The science and technology of ultrasound, its characteristics and phenomena. * * * ul·tra·son·ics .əl trə sän iks n pl but sing in constr 1) the science or technology of ultrasonic phenomena 2) ULTRASOUND (2) * * * n. the study of the uses and… …   Medical dictionary

  • ultrasonics — n. branch of science dealing with phenomena having a frequency above the range of sound audible to the human ear …   English contemporary dictionary

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