Sonoluminescence - Wikipedia, The Free Encyclopedia Long exposure image of multibubble sonoluminescence created by a high intensity ultrasonic horn immersed in a beaker of liquid. http://en.wikipedia.org/wiki/Sonoluminescence
Extractions: Jump to: navigation search Long exposure image of multi-bubble sonoluminescence created by a high intensity ultrasonic horn immersed in a beaker of liquid. Sonoluminescence is the emission of short bursts of light from imploding bubbles in a liquid when excited by sound The effect was first discovered at the University of Cologne in 1934 as a result of work on sonar H. Frenzel and H. Schultes put an ultrasound transducer in a tank of photographic developer fluid . They hoped to speed up the development process. Instead, they noticed tiny dots on the film after developing, and realized that the bubbles in the fluid were emitting light with the ultrasound turned on. It was too difficult to analyze the effect in early experiments because of the complex environment of a large number of short-lived bubbles. (This experiment is also ascribed to N. Marinesco and J.J. Trillat in 1933 which also credits them with independent discovery). This phenomenon is now referred to as multi-bubble sonoluminescence ( MBSL More than 50 years later, in
Sonoluminescence Homepage Maker of sonoluminescence kits. Provides instructions and suggested experiments. http://www.sonoluminescence.com/
Extractions: Back to contents About... Sonoluminescence was first observed in an ultrasonic water bath in 1934 by H. Frenzel and H. Schultes at the University of Cologne, an indirect result of wartime research in marine acoustic radar. This early work involved very strong ultrasonic fields and yielded clouds of unpredictable and non-synchronous flashing bubbles, now termed "multi-bubble sonoluminescence". Such a chaotic phenomenon did not lend itself to detailed scientific investigation. Study of sonoluminescence then made little progress until 1988, when D. Felipe Gaitan succeeded in trapping a stable sonoluminescing bubble at the centre of a flask energised at its acoustic resonance - single-bubble sonoluminescence (SBSL). However their interest soon waned, and the research was subsequently taken up by Dr S. Putterman et. al., at UCLA, California. Putterman pursued SBSL, published numerous papers, and established many of the characteristics which are now taken for granted. Once per acoustic cycle, coincident with a sharp decrease in bubble size, bluey-white light is emitted in a brief flash shorter than 100picoseconds in duration, with incredible regularity. Despite the results that have been obtained, the actual mechanism by which sound is converted to light remains elusive, not least because of the difficulty in measuring the conditions inside a pulsating bubble whose diameter is measured in micro-meters. It is generally agreed that the adiabatic compression of the bubble leads to very high interior temperatures, but beyond that, shocks, plasmas, ionisation and photo-recombination, Bremsstrahlung radiation, and even fusion are all hotly-debated possible explanations.
The Bubbles Produced By Ultrasound In Water (sonoluminescence Provides explanation of why it is unlikely that sonoluminescence produces the conditions necessary to initiate or facilitate nuclear fusion, as suggested in http://www.sciam.com/askexpert_question.cfm?articleID=000950E3-6815-1C71-9EB7809
Sonoluminescence One of the key unsolved problems of physics relates to the motion of continuous media and can be formulated as follows. Why is there a general tendency of http://www.physics.ucla.edu/Sonoluminescence/
Single Bubble Sonoluminescence HOWTO There are many papers about the theory of Single Bubble sonoluminescence available, but exact descriptions how to produce it are rare. http://www.macgeisler.de/nld/sbsl-howto.html
Extractions: Reinhard's Experimental Physics Letters (unpublished) 5/1996 There are many papers about the theory of Single Bubble Sonoluminescence available, but exact descriptions how to produce it are rare. So if you already know about sonoluminescence and now want to reproduce it, this is the right place to look at. I tried to give a complete and detailed report of the steps towards SBSL. Any suggestions, supplementations, comments are welcome... This experiment may be dangerous. Always think before you work. Working with vacuum or boiling water can cause explosions. High voltages are generated in this experiment. I will not be responsible for any injuries or damaged equipment. If you don't know what you are doing just don't do it at all. And: No, I am also not responsible for any thermonuclear accident you trigger. sine generator:
Boosting Sonoluminescence Accepted for publication in 1996, this paper describes how a bimodal sound excitation can enhance light production. http://www.physik.tu-darmstadt.de/~hofu/paper/boosting/main.html
Extractions: Received: September 26, 1996 Single bubble sonoluminescence has been experimentally produced through a novel approach of optimized sound excitation. A driving consisting of a first and second harmonic with selected amplitudes and relative phase results in an increase of light emission compared to sinusoidal driving. We achieved a raise of the maximum photo current of up to 300% with the two-mode sound signal. Numerical simulations of multi-mode excitation of a single bubble are compared to this result. PACS numbers: 78.60.Mq, 43.25.Yw, 42.65.Re, 02.60.Pn By focusing ultrasonic waves of high intensity into a liquid, thousands of tiny bubbles appear. This process of breakup of the liquid is called acoustic cavitation. The bubbles begin to form a fractal structure that is dynamically changing in time. They also emit a loud chaotic sound because of their forced nonlinear oscillations in the sound field [ ]. The large mechanical forces on objects brought into contact with the bubbles enable the usage of cavitation in cleaning, particle destruction and chemistry. Marinesco and Trillat [
Sonoluminescence - Creation Of Light From Sound Single Bubble sonoluminescence (SBSL) is the emission of flashes of light by imploding air bubbles in liquid. It was first observed as random flashes of http://www.chemsoc.org/ExemplarChem/entries/2004/bristol_eaimkhong/sonoluminesce
Extractions: Sounds into Reaction Home Introduction Theory Application ... Contact Applications of Sonochemistry(SC) Sonoluminescence Single Bubble Sonoluminescence (SBSL) is the emission of flashes of light by imploding air bubbles in liquid. It was first observed as random flashes of light during studies of cavitation. Recently, repetitive emission of SL has been produced under relatively stable, reproducible experimental conditions. The excellent stability of SL from single acoustically levitated bubbles has made possible detailed studies of the emission characteristics[2]. However, since each flash emits only about one million photons, these measurements have generally required averaging the characteristics over a large number of flashes. Fig6 - apparatus for single bubble sonoluminescence. The ultrasound is applied across the rounded bottom flask and hence bubble is created. Other applications Sonoluminescence Sonofusion Chemoluminescence Sonocrystalisation ... Sonocatalyst In single bubble sonoluminescence, the bubble is concentrating the energy of the acoustic vibrations be a factor of one trillion. The flashes are so brief that to measure the properties of light , we must use photodetectors that respond more quickly than those employed by high-energy physicists. And this is the only means of generating picosecond flashes of light that does not require expensive lasers, which might lead to development of nuclear fusion due to its achievement in focusing of energy.
Extractions: This illustration shows sonoluminescence at work, moving from upper right to lower left. At low sound-wave pressure, a gas bubble expands. An increase in pressure triggers its collapse, creating a smaller bubble of partly ionized gas. Temperatures soar, and the resulting plasma emits light that is detected in the experiment. By By Michael Schirber Just as blowing up a bubble leads to a pop, so can shrinking it. Rapidly collapsing bubbles have long been known to reach astonishing temperatures. Now scientists have measured just how hot. And they're surprised. "When bubbles in a liquid get compressed, the insides get hot â very hot," said Ken Suslick of the University of Illinois at Urbana-Champaign. "The temperature we measured â about 20,000 degrees Kelvin [35,540 degrees Fahrenheit] â is four times hotter than the surface of our Sun." The bubbles are driven to form and collapse in a process called sonoluminescence, in which a liquid is blasted with high-frequency sound waves between 20 and 40 kilohertz (the highest pitch that humans can hear is about 20 kilohertz).
Sonoluminescence sonoluminescence is the initiation of bright flashes of light caused by imposing a loud, high frequency sound on a gas bubble contained within a liquid. http://www.halexandria.org/dward166.htm
Extractions: Sonoluminescence is the initiation of bright flashes of light caused by imposing a loud, high frequency sound on a gas bubble contained within a liquid. According to one report [1] sound (typically 110 decibels at 25,000 Hertz) can cause a single air bubble in water to oscillate. As the pressure of the sound wave decreases (in the normal course of a single cycle of increasing and decreasing pressure), the bubbles internal pressure causes it to increase in size to a maximum radius of about 70 micrometers. As the external pressure of the sound wave increases, the bubble begins to collapse. This collapse occurs partway through the rise in external pressure (and lasts about 15 x 10 seconds). The collapsing bubble walls shrink the bubble to less than a hundredth of its maximum size in about 15 microseconds. Then, as the bubble nears its minimum size, it emits a bright flash of light. The maximum duration of the flash of light is about 50 picoseconds (50 x 10 seconds). The bubble then oscillates about its minimum radius for a short time, before the cycle repeats itself. The temperature rise inside the bubble is estimated to rise to between 100,000 and a million degrees Kelvin, and the internal pressures to as much as 100 million times atmospheric pressure.
Extractions: Sonoluminescence and Medical Ultrasound Scientists have found evidence that medical ultrasound devices can produce sonoluminescence. This figure shows the calculated acoustic field of a device used in medicine to induce therapeutic lesions in tissue. This acoustic field generates intense sonoluminescence, although not so much at the focus, where one would expect it to be the most intense. (Figures courtesy of Lawrence Crum, University of Washington) Back to Physics News Graphics Main Page
What Is Sonoluminescence? Brief and Straightforward Guide What is sonoluminescence? http://www.wisegeek.com/what-is-sonoluminescence.htm
Extractions: ad_unit_target='mainAdUnit'; X Close this window Sonoluminescence is a mysterious phenomenon caused when ultrasound waves excite a liquid, creating tiny bubbles which emit light when they collapse. The effect is magnified when the bubbles contain a noble gas . The phrase sonoluminescence means "sound light". There are various theories about sonoluminescence, none of which have been conclusively proven. Temperatures of above 20,000 K have been measured at the centres of these tiny bubbles. This is hot enough to boil diamond. The phenomenon of sonoluminescence was popularized in the film Chain Reaction starring Keanu Reeves. In the movie, sonoluminescence is used to kickstart a nuclear fusion reaction. Bubbles created by sonoluminescence have been observed generating temperatures measuring in the kilokelvins , or tens of thousands of degrees. The temperature threshold to initiate nuclear fusion reactions is in the millions of degrees, or megakelvins . There is a bit of a discrepancy here, a discrepancy adding up to three orders of magnitude. Sonoluminescence is hot, but it's not that hot. Researchers from the lab of Purdue scientist R. P. Taleyarkhan claimed that, under sonoluminescence, an acetone-filled vessel emitted neutrons at a
Extractions: Sonoluminescence isn't a household name, but it could soon shake up the world of nuclear physics. Sonoluminescence, or light from sound, was first observed in 1934 by German scientists who put an ultrasound generator in a tank of photographic developer. They hoped that vibrating the fluid at frequencies higher than humans can hear would speed up the development process. Instead, the emulsion-coated plates emerged with spots. On closer inspection, they found that when the ultrasound generator was turned on, the bubble-filled fluid emitted a faint glow. It was this light that damaged the plates. All of this was very intriguing. But with digital computers yet to be invented, there was no way to study the unwieldy mass of short-lived bubbles in the developer fluid. It's all in the bubbles Sonoluminescence was put on the shelf and pretty much ignored for more than 50 years. Then, in 1989, Lawrence Crum, then a professor at the University of Mississippi, and Felipe Gaitan, one of his graduate students, devised a way to study the phenomenon: They would look at one bubble at a time.
Bubbles Feel The Heat - Physicsworld.com Physicists have seen a region of plasma in a singlebubble sonoluminescence experiment for the first time. They have also found that the temperature inside http://physicsworld.com/cws/article/news/21654
Extractions: @import url(/cws/css/screen.css); @import url(/cws/css/themes/phw.css); @import url(/cws/css/datePicker.css); Skip to the content A community website from IOP Publishing physicsworld.com ... Advertising Whole site Print edition News In depth Jobs Events Companies Products Search For maximum exposure, become a Corporate Partner. Contact our sales team Corporate Partners Mar 3, 2005 Physicists have seen a region of plasma in a single-bubble sonoluminescence experiment for the first time. They have also found that the temperature inside the bubble can reach up to 20,000 K (D Flannigan and K Suslick 2005 Nature Collapsing bubbles In sonoluminescence, the bubbles in a liquid emit light when they are forced to expand and collapse by sound waves. Some physicists believe that the pressures and temperatures inside the collapsing bubbles could be high enough to initiate nuclear reactions. However, the experimental evidence for "sonofusion" remains controversial. In the latest experiments Kenneth Suslick and Daniel Flannigan of the University of Illinois at Urbana-Champaign find evidence for the formation of a plasma in collapsing bubbles. According to Suslick and Flannigan the formation of a plasma is a prerequisite for a form of fusion known as inertial confinement fusion to take place inside the bubble.
SONOLUMINESCENCE | Home Sound, light, dance improvisation by Todd Barton, Terry Longshore, Michael Maag, Suzee Grilley and Bruce Bayard. http://www.sonoluminescence.us/
Extractions: THE CHEMICAL AND PHYSICAL EFFECTS OF ULTRASOUND Kenneth S. Suslick The research team led by Professor Suslick has pioneered the exploration of ultrasound as a tool for chemists. He has developed new applications of sonochemistry in organometallic, inorganic, materials, and biological chemistry. His research at the UIUC has developed new approaches to amorphous and nanostructured materials, has shown great promise for the activation of heterogeneous catalysts, and has created a whole new class of medically important biomaterials. For a listing of commercially available sonochemical equipment, click here. Background The chemical effects of ultrasound do not come from a direct interaction with molecular species. Instead, sonochemistry and sonoluminescence arises from acoustic cavitation: the formation, growth, and implosive collapse of bubbles in a liquid. Cavitational collapse produces intense K/sec). Acoustic cavitation provides a unique interaction of energy and matter, and ultrasonic irradiation of liquids causes high energy chemical reactions to occur, often accompanied by the emission of light [1]. Acoustic Cavitation: the formation, growth, and implosive collapse of bubbles in a liquid irradiated with high intensity ultrasound.
Extractions: The world's premier software reference source. A selection of articles discussing this topic. ...the cavitation process and its applications. A contemporary subject of research involves emission of light as the cavity produced by a high-intensity ultrasonic wave collapses. This effect, called sonoluminescence, is believed to create instantaneous temperatures hotter than the surface of the Sun. ...reactions (neutrons and tritium) during acoustic cavitation experiments with chilled deuterated (bombarded with deuterium) acetone. Their experimental setup was based on the known phenomenon of sonoluminescence. In sonoluminescence a gas bubble is imploded with high-pressure sound waves. At the end of the implosion process, and for a short time afterward, conditions of high density and...
Extractions: We have proposed a benchmark experiment that will probe the effects of gravity on Single Bubble Sonoluminescence (SBSL). SBSL has been the topic of many exciting research efforts in the past decade, yet there still remain several critical characteristics of the phenomenon to "decipher": (1) the light emission mechanism; (2) the disappearance of the bubble at some critical acoustic pressure; and (3) the appearance of quasiperiodic and chaotic oscillations in flash timing. Gravity, in the context of time-varying buoyancy , is implicated in these unexplained phenomena which have all been observed in 1g experiments.
Access : : Nature Singlebubble sonoluminescence is the remarkable phenomenon that describes Figure 1 Glowing bubbles a sound wave in liquid causes sonoluminescence. http://www.nature.com/nature/journal/v418/n6896/full/418381b.html
Extractions: Login Search This journal All of Nature.com Advanced search To read this story in full you will need to login or make a payment (see right). Journal home Archive News and Views Full Text Nature doi Detlef Lohse Top of page Gas bubbles in a liquid can convert sound energy into light. Detailed measurements of a single bubble show that, in fact, most of the sound energy goes into chemical reactions taking place inside this 'micro-reactor'. 'Single-bubble sonoluminescence' is the remarkable phenomenon that describes how a gas bubble in liquid, exposed to a strong, standing sound wave, collapses and emits light. First observed 12 years ago , the basic physics of the process seems to be understood To read this story in full you will need to login or make a payment (see right). Personal subscribes to Nature can view this article. To do this, you need to associate your subscription with your registration via the