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Kenneth S. Suslick - One of the best experts on this subject based on the ideXlab platform.
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Plasma conditions during single Bubble sonoluminescence.
Journal of the Acoustical Society of America, 2009Co-Authors: Kenneth S. Suslick, David J. FlanniganAbstract:There is a remarkable lack of experimental data on the conditions created during Cavitation Bubble collapse. Indeed, only recently has strong evidence of plasma formation been obtained during single Bubble Cavitation. Here we have determined for the first time the plasma electron density and the ion broadening parameter during single‐Bubble sonoluminescence and examined them as a function of acoustic driving pressure. We find that the electron density spans four orders of magnitude and can exceed 10×1021/cc (which is comparable to the densities produced by intense laser‐induced inertial confinement fusion experiments, e.g., the NOVA ICF laser at Livermore) with effective plasma temperatures ranging from 7000 to more than 16 000 K. At the highest acoustic driving force, neutral Ar lines can no longer be used as spectroscopic reporters due to the extent of ionization and to leveling of the population of states. Accounting for the temporal profile of the sonoluminescence pulse suggests that the ultimate cond...
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plasma line emission during single Bubble Cavitation
Physical Review Letters, 2005Co-Authors: David J. Flannigan, Kenneth S. SuslickAbstract:Emission lines from transitions between high-energy states of noble-gas atoms (Ne, Ar, Kr, and Xe) and ions (Ar(+), Kr(+), and Xe(+)) formed and excited during single-Bubble Cavitation in sulfuric acid are reported. The excited states responsible for these emission lines range 8.3 eV (for Xe) to 37.1 eV (for Ar(+)) above the respective ground states. Observation of emission lines allows for identification of intracavity species responsible for light emission; the populated energy levels indicate the plasma generated during Cavitation is comprised of highly energetic particles.
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plasma formation and temperature measurement during single Bubble Cavitation
Nature, 2005Co-Authors: David J. Flannigan, Kenneth S. SuslickAbstract:Single-Bubble sonoluminescence (SBSL) results from the extreme temperatures and pressures achieved during Bubble compression; calculations have predicted the existence of a hot, optically opaque plasma core with consequent bremsstrahlung radiation. Recent controversial reports claim the observation of neutrons from deuterium-deuterium fusion during acoustic Cavitation. However, there has been previously no strong experimental evidence for the existence of a plasma during single- or multi-Bubble sonoluminescence. SBSL typically produces featureless emission spectra that reveal little about the intra-cavity physical conditions or chemical processes. Here we report observations of atomic (Ar) emission and extensive molecular (SO) and ionic (O2+) progressions in SBSL spectra from concentrated aqueous H2SO4 solutions. Both the Ar and SO emission permit spectroscopic temperature determinations, as accomplished for multi-Bubble sonoluminescence with other emitters. The emissive excited states observed from both Ar and O2+ are inconsistent with any thermal process. The Ar excited states involved are extremely high in energy (>13 eV) and cannot be thermally populated at the measured Ar emission temperatures (4,000-15,000 K); the ionization energy of O2 is more than twice its bond dissociation energy, so O2+ likewise cannot be thermally produced. We therefore conclude that these emitting species must originate from collisions with high-energy electrons, ions or particles from a hot plasma core.
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plasma formation and temperature measurement during single Bubble Cavitation
Nature, 2005Co-Authors: David J. Flannigan, Kenneth S. SuslickAbstract:The phenomenon known as single-Bubble sonoluminescence (SBSL) has been the focus of intense investigation since it was discovered 15 years ago, leading to predictions that extreme temperatures are reached within the cavity at extreme compression. Conditions, some have controversially claimed, that could even lead to nuclear fusion. The lack of features in the typical SBSL spectrum has made it difficult to establish what is happening within the Bubble. But now, using concentrated sulphuric acid as the medium subjected to acoustic treatment, Flannigan and Suslick have obtained the most intense sonoluminescence yet seen. This provides plenty of spectral information — most importantly, evidence for temperatures as high as 15,000 K — indicating that the collapsed Bubble has a hot plasma core. Single-Bubble sonoluminescence (SBSL1,2,3,4,5) results from the extreme temperatures and pressures achieved during Bubble compression; calculations have predicted6,7 the existence of a hot, optically opaque plasma core8 with consequent bremsstrahlung radiation9,10. Recent controversial reports11,12 claim the observation of neutrons from deuterium–deuterium fusion during acoustic Cavitation11,12. However, there has been previously no strong experimental evidence for the existence of a plasma during single- or multi-Bubble sonoluminescence. SBSL typically produces featureless emission spectra13 that reveal little about the intra-cavity physical conditions or chemical processes. Here we report observations of atomic (Ar) emission and extensive molecular (SO) and ionic (O2+) progressions in SBSL spectra from concentrated aqueous H2SO4 solutions. Both the Ar and SO emission permit spectroscopic temperature determinations, as accomplished for multi-Bubble sonoluminescence with other emitters14,15,16. The emissive excited states observed from both Ar and O2+ are inconsistent with any thermal process. The Ar excited states involved are extremely high in energy (>13 eV) and cannot be thermally populated at the measured Ar emission temperatures (4,000–15,000 K); the ionization energy of O2 is more than twice its bond dissociation energy, so O2+ likewise cannot be thermally produced. We therefore conclude that these emitting species must originate from collisions with high-energy electrons, ions or particles from a hot plasma core.
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Chemical control of single Bubble Cavitation
Journal of the Acoustical Society of America, 2003Co-Authors: Yuri T. Didenko, Kenneth S. SuslickAbstract:Sonochemistry would be ideally studied with a single Bubble with known size pulsating in known acoustic pressure field. Single Bubble Cavitation provides the means to make such studies. The promise that single Bubble Cavitation brought to the quantitative measurements of chemical activity of Cavitation, however, has not been previously fulfilled due to the very small amount of reacting gas within a single Bubble (typically
David J. Flannigan - One of the best experts on this subject based on the ideXlab platform.
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Plasma conditions during single Bubble sonoluminescence.
Journal of the Acoustical Society of America, 2009Co-Authors: Kenneth S. Suslick, David J. FlanniganAbstract:There is a remarkable lack of experimental data on the conditions created during Cavitation Bubble collapse. Indeed, only recently has strong evidence of plasma formation been obtained during single Bubble Cavitation. Here we have determined for the first time the plasma electron density and the ion broadening parameter during single‐Bubble sonoluminescence and examined them as a function of acoustic driving pressure. We find that the electron density spans four orders of magnitude and can exceed 10×1021/cc (which is comparable to the densities produced by intense laser‐induced inertial confinement fusion experiments, e.g., the NOVA ICF laser at Livermore) with effective plasma temperatures ranging from 7000 to more than 16 000 K. At the highest acoustic driving force, neutral Ar lines can no longer be used as spectroscopic reporters due to the extent of ionization and to leveling of the population of states. Accounting for the temporal profile of the sonoluminescence pulse suggests that the ultimate cond...
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plasma line emission during single Bubble Cavitation
Physical Review Letters, 2005Co-Authors: David J. Flannigan, Kenneth S. SuslickAbstract:Emission lines from transitions between high-energy states of noble-gas atoms (Ne, Ar, Kr, and Xe) and ions (Ar(+), Kr(+), and Xe(+)) formed and excited during single-Bubble Cavitation in sulfuric acid are reported. The excited states responsible for these emission lines range 8.3 eV (for Xe) to 37.1 eV (for Ar(+)) above the respective ground states. Observation of emission lines allows for identification of intracavity species responsible for light emission; the populated energy levels indicate the plasma generated during Cavitation is comprised of highly energetic particles.
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plasma formation and temperature measurement during single Bubble Cavitation
Nature, 2005Co-Authors: David J. Flannigan, Kenneth S. SuslickAbstract:Single-Bubble sonoluminescence (SBSL) results from the extreme temperatures and pressures achieved during Bubble compression; calculations have predicted the existence of a hot, optically opaque plasma core with consequent bremsstrahlung radiation. Recent controversial reports claim the observation of neutrons from deuterium-deuterium fusion during acoustic Cavitation. However, there has been previously no strong experimental evidence for the existence of a plasma during single- or multi-Bubble sonoluminescence. SBSL typically produces featureless emission spectra that reveal little about the intra-cavity physical conditions or chemical processes. Here we report observations of atomic (Ar) emission and extensive molecular (SO) and ionic (O2+) progressions in SBSL spectra from concentrated aqueous H2SO4 solutions. Both the Ar and SO emission permit spectroscopic temperature determinations, as accomplished for multi-Bubble sonoluminescence with other emitters. The emissive excited states observed from both Ar and O2+ are inconsistent with any thermal process. The Ar excited states involved are extremely high in energy (>13 eV) and cannot be thermally populated at the measured Ar emission temperatures (4,000-15,000 K); the ionization energy of O2 is more than twice its bond dissociation energy, so O2+ likewise cannot be thermally produced. We therefore conclude that these emitting species must originate from collisions with high-energy electrons, ions or particles from a hot plasma core.
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plasma formation and temperature measurement during single Bubble Cavitation
Nature, 2005Co-Authors: David J. Flannigan, Kenneth S. SuslickAbstract:The phenomenon known as single-Bubble sonoluminescence (SBSL) has been the focus of intense investigation since it was discovered 15 years ago, leading to predictions that extreme temperatures are reached within the cavity at extreme compression. Conditions, some have controversially claimed, that could even lead to nuclear fusion. The lack of features in the typical SBSL spectrum has made it difficult to establish what is happening within the Bubble. But now, using concentrated sulphuric acid as the medium subjected to acoustic treatment, Flannigan and Suslick have obtained the most intense sonoluminescence yet seen. This provides plenty of spectral information — most importantly, evidence for temperatures as high as 15,000 K — indicating that the collapsed Bubble has a hot plasma core. Single-Bubble sonoluminescence (SBSL1,2,3,4,5) results from the extreme temperatures and pressures achieved during Bubble compression; calculations have predicted6,7 the existence of a hot, optically opaque plasma core8 with consequent bremsstrahlung radiation9,10. Recent controversial reports11,12 claim the observation of neutrons from deuterium–deuterium fusion during acoustic Cavitation11,12. However, there has been previously no strong experimental evidence for the existence of a plasma during single- or multi-Bubble sonoluminescence. SBSL typically produces featureless emission spectra13 that reveal little about the intra-cavity physical conditions or chemical processes. Here we report observations of atomic (Ar) emission and extensive molecular (SO) and ionic (O2+) progressions in SBSL spectra from concentrated aqueous H2SO4 solutions. Both the Ar and SO emission permit spectroscopic temperature determinations, as accomplished for multi-Bubble sonoluminescence with other emitters14,15,16. The emissive excited states observed from both Ar and O2+ are inconsistent with any thermal process. The Ar excited states involved are extremely high in energy (>13 eV) and cannot be thermally populated at the measured Ar emission temperatures (4,000–15,000 K); the ionization energy of O2 is more than twice its bond dissociation energy, so O2+ likewise cannot be thermally produced. We therefore conclude that these emitting species must originate from collisions with high-energy electrons, ions or particles from a hot plasma core.
Yuri T. Didenko - One of the best experts on this subject based on the ideXlab platform.
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Chemical control of single Bubble Cavitation
Journal of the Acoustical Society of America, 2003Co-Authors: Yuri T. Didenko, Kenneth S. SuslickAbstract:Sonochemistry would be ideally studied with a single Bubble with known size pulsating in known acoustic pressure field. Single Bubble Cavitation provides the means to make such studies. The promise that single Bubble Cavitation brought to the quantitative measurements of chemical activity of Cavitation, however, has not been previously fulfilled due to the very small amount of reacting gas within a single Bubble (typically
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the energy efficiency of formation of photons radicals and ions during single Bubble Cavitation
Nature, 2002Co-Authors: Yuri T. Didenko, Kenneth S. SuslickAbstract:It is extremely difficult to perform a quantitative analysis of the chemistry1,2 associated with multiBubble Cavitation: unknown parameters include the number of active Bubbles, the acoustic pressure acting on each Bubble and the Bubble size distribution. Single-Bubble sonoluminescence3,4,5,6,7 (characterized by the emission of picosecond flashes of light) results from nonlinear pulsations of an isolated vapour-gas Bubble in an acoustic field. Although the latter offers a much simpler environment in which to study the chemical activity of Cavitation, quantitative measurements have been hindered by the tiny amount of reacting gas within a single Bubble (typically <10-13 mol). Here we demonstrate the existence of chemical reactions within a single cavitating Bubble, and quantify the sources of energy dissipation during Bubble collapse. We measure the yields of nitrite ions, hydroxyl radicals and photons. The energy efficiency of hydroxyl radical formation is comparable to that in multiBubble Cavitation, but the energy efficiency of light emission is much higher. The observed rate of nitrite formation is in good agreement with the calculated diffusion rate of nitrogen into the Bubble. We note that the temperatures attained in single-Bubble Cavitation in liquids with significant vapour pressures will be substantially limited by the endothermic chemical reactions of the polyatomic species inside the collapsing Bubble.
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Molecular emission from single-Bubble sonoluminescence.
Nature, 2000Co-Authors: Yuri T. Didenko, William B. Mcnamara, Kenneth S. SuslickAbstract:Ultrasound can drive a single gas Bubble in water into violent oscillation; as the Bubble is compressed periodically, extremely short flashes of light (about 100 ps) are generated with clock-like regularity1,2,3,4. This process, known as single-Bubble sonoluminescence, gives rise to featureless continuum emission4,5 in water (from 200 to 800 nm, with increasing intensity into the ultraviolet). In contrast, the emission of light from clouds of cavitating Bubbles at higher acoustic pressures (multi-Bubble sonoluminescence1) is dominated by atomic and molecular excited-state emission6,7,8,9,10,11 at much lower temperatures6. These observations have spurred intense effort to uncover the origin of sonoluminescence and to generalize the conditions necessary for its creation. Here we report a series of polar aprotic liquids that generate very strong single-Bubble sonoluminescence, during which emission from molecular excited states is observed. Previously, single-Bubble sonoluminescence from liquids other than water has proved extremely elusive12,13. Our results give direct proof of the existence of chemical reactions and the formation of molecular excited states during single-Bubble Cavitation, and provide a spectroscopic link between single- and multi-Bubble sonoluminescence.
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sonoluminescence temperatures during multi Bubble Cavitation
Nature, 1999Co-Authors: William B. Mcnamara, Yuri T. Didenko, Kenneth S. SuslickAbstract:Acoustic Cavitation—the formation and implosive collapse of Bubbles—occurs when a liquid is exposed to intense sound. Cavitation can produce white noise, sonochemical reactions, erosion of hard materials, rupture of living cells and the emission of light, or sonoluminescence1,2. The concentration of energy during the collapse is enormous: the energy of an emitted photon can exceed the energy density of the sound field by about twelve orders of magnitude3, and it has long been predicted that the interior Bubble temperature reaches thousands of degrees Kelvin during collapse. But experimental measurements4,5 of conditions inside cavitating Bubbles are scarce, and there have been no studies of interior temperature as a function of experimental parameters. Here we use multi-Bubble sonoluminescence from excited states of metal atoms as a spectroscopic probe of temperatures inside cavitating Bubbles. The intense atomic emission allows us to change the properties of the gas–vapour mixture within the Bubble, and thus vary the effective emission temperature for multi-Bubble sonoluminescence from 5,100 to 2,300 K. We observe emission temperatures that are in accord with those expected from compressional heating during Cavitation.
Clausdieter Ohl - One of the best experts on this subject based on the ideXlab platform.
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sonoporation of suspension cells with a single Cavitation Bubble in a microfluidic confinement
Lab on a Chip, 2007Co-Authors: Severine Le Gac, Ed Zwaan, Albert Van Den Berg, Clausdieter OhlAbstract:We report here the sonoporation of HL60 (human promyelocytic leukemia) suspension cells in a microfluidic confinement using a single laser-induced Cavitation Bubble. Cavitation Bubbles can induce membrane poration of cells located in their close vicinity. Membrane integrity of suspension cells placed in a microfluidic chamber is probed through either the calcein release out of calcein-loaded cells or the uptake of trypan blue. Cells that are located farther away than four times R-max (maximum Bubble radius) from the Cavitation Bubble center remain fully unaffected, while cells closer than 0.75 R-max become porated with a probability of >75%. These results enable us to define a distance of 0.75 R-max as a critical interaction distance of the Cavitation Bubble with HL60 suspension cells. These experiments suggest that flow-induced poration of suspension cells is applicable in lab-on-a-chip systems, and this might be an interesting alternative to electroporation.
Malisa Sarntinoranont - One of the best experts on this subject based on the ideXlab platform.
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controlled single Bubble Cavitation collapse results in jet induced injury in brain tissue
Journal of The Mechanical Behavior of Biomedical Materials, 2017Co-Authors: Saranya Canchi, Ghatu Subhash, Yu Hong, Michael A. King, Karen Kelly, Malisa SarntinoranontAbstract:Multiscale damage due to Cavitation is considered as a potential mechanism of traumatic brain injury (TBI) associated with explosion. In this study, we employed a TBI relevant hippocampal ex vivo slice model to induce Bubble Cavitation. Placement of single reproducible seed Bubbles allowed control of size, number, and tissue location to visualize and measure deformation parameters. Maximum strain value was measured at 45 µs after Bubble collapse, presented with a distinct contour and coincided temporally and spatially with the liquid jet. Composite injury maps combined this maximum strain value with maximum measured Bubble size and location along with histological injury patterns. This facilitated the correlation of Bubble location and subsequent jet direction to the corresponding regions of high strain which overlapped with regions of observed injury. A dynamic threshold strain range for tearing of cerebral cortex was estimated to be between 0.5 and 0.6. For a seed Bubble placed underneath the hippocampus, Cavitation induced damage was observed in hippocampus (local), proximal cerebral cortex (marginal) and the midbrain/forebrain (remote) upon histological evaluation. Within this test model, zone of Cavitation injury was greater than the maximum radius of the Bubble. Separation of apposed structures, tissue tearing, and disruption of cellular layers defined early injury patterns that were not detected in the blast-exposed half of the brain slice. Ultrastructural pathology of the neurons exposed to Cavitation was characterized by disintegration of plasma membrane along with loss of cellular content. The developed test system provided a controlled experimental platform to study Cavitation induced high strain deformations on brain tissue slice. The goal of the future studies will be to lower underpressure magnitude and Cavitation Bubble size for more sensitive evaluation of injury.
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Damage in Brain Tissue Due to Single Bubble Cavitation Shock
Mechanics of Biological Systems and Materials Volume 6, 2016Co-Authors: Ghatu Subhash, Saranya Canchi, Yu Hong, Malisa Sarntinoranont, Michael A. KingAbstract:A novel experimental technique was developed to visualize and control single Bubble Cavitation initiation, growth, and its collapse. The influence of this process on a nearby tissue surrogate was investigated and then extended to a rat brain tissue. The technique utilized a modified polymer Hopkinson pressure bar system which transmits a simulated blast pressure wave with over and under pressure components to a fluid-filled test chamber implanted with a seed gas Bubble. Growth and collapse of this Bubble was visually recorded with a high speed camera. Using Raleigh-Plessat equation, Bubble collapse pressures 29–125 times that of peak blast overpressure are predicted to be the source of localized shock waves. Finally, the value of this experimental platform to investigate the single Bubble Cavitation-induced fluid jet impact on a rat brain tissue and the associated damage evolution is illustrated.
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localized tissue surrogate deformation due to controlled single Bubble Cavitation
Experimental Mechanics, 2016Co-Authors: Yu Hong, Saranya Canchi, Malisa Sarntinoranont, Michael A. King, Ghatu SubhashAbstract:Cavitation-induced shock wave, as might occur in the head during exposure to blast waves, was investigated as a possible damage mechanism for soft brain tissues. A novel experimental technique was developed to visualize and control single Bubble Cavitation and its collapse, and the influence of this process on a nearby tissue surrogate was investigated. The experiment utilized a Hopkinson pressure bar system which transmits a simulated blast pressure wave (with over-pressure and under-pressure components) to a fluid-filled test chamber implanted with a seed gas Bubble. Growth and collapse of this Bubble was recorded during passage of the blast wave with a high speed camera. To investigate the potential for Cavitation damage to a tissue surrogate, local changes in strain were measured in hydrogel slices placed in various configurations next to the Bubble. The strain measurements were made using digital image correlation (DIC) technique by monitoring the motion of material points on the tissue surrogate. In one configuration, Bubble contact dynamics resulted in compression contact (>60 μs) followed by inertially-driven tension (>140 μs). In another configuration, the influence of local shock waves emanating from collapsed Bubbles was captured. Large compressive strains (0.25 to 0.5) that were highly localized (0.18 mm2) were measured over a short time period (<24 μs) after Bubble collapse. High Bubble collapse pressures 29 to 125 times that of peak blast overpressure are predicted to be the source of these large strains. Consistent with theoretical predictions, these Cavitation-based strains are far larger than the strains imposed by passage of the simulated blast wave alone. Finally, the value of this experimental platform to investigate the single Bubble Cavitation-induced damage in a biological tissue is illustrated with an example test on rat brain slices.
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Localized Tissue Surrogate Deformation due to Controlled Single Bubble Cavitation
Experimental Mechanics, 2016Co-Authors: Yu Hong, Ghatu Subhash, Saranya Canchi, Malisa Sarntinoranont, Michael A. KingAbstract:Cavitation-induced shock wave, as might occur in the head during exposure to blast waves, was investigated as a possible damage mechanism for soft brain tissues. A novel experimental technique was developed to visualize and control single Bubble Cavitation and its collapse, and the influence of this process on a nearby tissue surrogate was investigated. The experiment utilized a Hopkinson pressure bar system which transmits a simulated blast pressure wave (with over-pressure and under-pressure components) to a fluid-filled test chamber implanted with a seed gas Bubble. Growth and collapse of this Bubble was recorded during passage of the blast wave with a high speed camera. To investigate the potential for Cavitation damage to a tissue surrogate, local changes in strain were measured in hydrogel slices placed in various configurations next to the Bubble. The strain measurements were made using digital image correlation (DIC) technique by monitoring the motion of material points on the tissue surrogate. In one configuration, Bubble contact dynamics resulted in compression contact (>60 μs) followed by inertially-driven tension (>140 μs). In another configuration, the influence of local shock waves emanating from collapsed Bubbles was captured. Large compressive strains (0.25 to 0.5) that were highly localized (0.18 mm^2) were measured over a short time period (
