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G. L. Sharipov - One of the best experts on this subject based on the ideXlab platform.
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confirmation of hydrated electrons formation during the moving single bubble Sonolysis activation of tb3 ion sonoluminescence by eaq acceptors in an aqueous solution
Journal of Photochemistry and Photobiology A-chemistry, 2020Co-Authors: G. L. Sharipov, B M Gareev, A. M. AbdrakhmanovAbstract:Abstract The acoustically excited (26 kHz, acoustic pressure of 1.34 bar) luminescence of Tb3+ ions in aqueous solutions of TbCl3 is activated by selective acceptors of hydrated electron ( e a q - ), namely H+, and Cd2+ ions and other, during the moving single-bubble Sonolysis. Sonoluminescence of Tb3+ is quenched when solvated electrons are present. The Tb3+ ions penetrate into the bubble across the liquid-gas interface, which is deformed during the bubble movement with the formation of microjets and nanodroplet injection. Then these ions are transferred to the electronically excited state upon inelastic collisions with particles having excess kinetic energy. The excited ions (*Tb3+, lifetime more than 400 μs) partly emit photons in the bubble and partly migrate to the solution, together with other Sonolysis products as a result of their ejection from a bubble into a liquid. In the solution, the *Tb3+ ions react with the radical products of H2O Sonolysis. The detected activation of the Tb3+ sonoluminescence is similar to the known activation of Tb3+ radioluminescence by e a q - acceptors (radiolysis generates e a q - together with *Tb3+). However, such activation is absent in the case of multibubble Sonolysis, for which *Tb3+ generation was established previously, but no e a q - was formed among the primary products of H2O Sonolysis (H and OH•). These facts indicate that acceptors suppress the reaction in which e a q - eliminates the excited state of the terbium ion *Tb3+ + e a q - → Tb2+. It is obvious considering the known redox potentials of the reactants. Consequently, hydrated electrons are generated in the moving single-bubble Sonolysis of water.
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electron stimulated luminescence of mathbf ru bpy _ mathbf 3 mathbf 2 in the Sonolysis of solutions of mathbf ru bpy _ mathbf 3 mathbf 2 and mathbf ru bpy _ mathbf 3 mathbf 3
Bulletin of The Russian Academy of Sciences: Physics, 2020Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, B M Gareev, L R YakshembetovaAbstract:The role of hydrated electrons in sonochemiluminescence (SCL) arising from the single- and multibubble Sonolysis of aqueous solutions of $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{2 + }}}}$$ and $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{3 + }}}}$$ is revealed. Possible chemiluminescent reactions between ruthenium ions and the products of water Sonolysis are considered. A conclusion is drawn concerning the previously unknown formation of eaq upon the single-bubble Sonolysis of water and the absence of this product upon multibubble Sonolysis.
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sonochemiluminescence of ru bpy 33 in aqueous solutions evidence of the formation of hydrated electrons during the single bubble Sonolysis in a neutral aqueous medium
Ultrasonics Sonochemistry, 2019Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, L R Yakshembetova, B M GareevAbstract:Abstract Consideration is given to single and multibubble sonochemiluminescence (SCL) in acidic Ru(bpy)33+ aqueous solutions due to the light emission of the excited ion *Ru(bpy)32+ at 613 nm. Spectrophotometrically controlled reduction of Ru(bpy)33+ to Ru(bpy)32+ occurs in both regimes of Sonolysis. The kinetics parameters of reduction under SCL during the multibubble Sonolysis do not depend on the H+ concentration in the solution (0.005 and 0.5 M H2SO4), but differ for the single-bubble Sonolysis. The intensity of single-bubble SCL is maximal at the beginning of Sonolysis and monotously decreases to the level of steady-state SCL after complete reduction of Ru(bpy)33+ to Ru(bpy)32+. The intensity of multibubble SCL at the beginning of Sonolysis is below the recognition threshold. Then it grows, passes through the maximum and also approaches the steady-state level after the reduction of ruthenium. By considering possible chemiluminescent reactions Ru(bpy)33+ + eaq → *Ru(bpy)32+, Ru(bpy)33+ + H → *Ru(bpy)32+ + H+, Ru(bpy)33+ + Ru(bpy)3+ → *Ru(bpy)32+ + Ru(bpy)32+ as well as the reactions of sonochemical formation of Ru(bpy)33+ and Ru(bpy)3+ from Ru(bpy)32+ and the reaction H+ + eaq → H, the conclusion is made about the generation of eaq during the single-bubble Sonolysis of water molecules. The presence and absence of eaq during the single and multibubble Sonolysis respectively explain the distinctions in the SCL kinetics. The evidence for the generation of eaq lies also in the reduction of the Fe(CN)63− ion observed during the single-bubble Sonolysis in the neutral solution, which is impossible without eaq. The yield of eaq is comparable to that of the hydrogen atom.
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spectroscopic measurement of electronic temperature in the bubbles during single and multibubble sonoluminescence of metal carbonyl solutions and nanodispersed suspensions
Ultrasonics Sonochemistry, 2019Co-Authors: G. L. Sharipov, B M Gareev, A. M. AbdrakhmanovAbstract:Abstract It is for the first time that we have obtained emission-line spectra of metal atoms during single-bubble sonoluminescence of metal carbonyl W(CO)6, Mo(CO)6, Cr(CO)6 solutions in dodecane and similar spectra during single- and multibubble sonoluminescence of nanodispersed Cr(CO)6 suspensions in water, 83% H2SO4 and 74% H3PO4. Nanodispersed suspensions with an average particle size of 15–20 nm were obtained through sonodispersing and filtering Cr(CO)6 crystals in water. The method for comparing the intensities of two atomic metal lines made it possible to measure the electronic temperatures achieved in cavitation bubbles under different modes of Sonolysis that vary in the range of (4.5–16)·103 K depending on the mode of Sonolysis, the type of liquid and saturating gas (He, Ar, Kr) and the acoustic energy entering the solution or suspension. The electronic temperature for multibubble sonoluminescence is, on the average, by (2–2.5)·103 K less than for single-bubble sonoluminescence for all liquids in question.
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luminescence of tb 3 and gd 3 ions in Sonolysis under the conditions of a single bubble moving in aqueous solutions of tbcl 3 and gdcl 3
Technical Physics, 2013Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, B M GareevAbstract:Luminescence bands of Tb3+ and Gd3+ ions are detected during Sonolysis in the regime of a moving single bubble in aqueous solutions of TbCl3 and GdCl3 salts with concentration 1–2 mol/L. Saturation with argon, low temperatures of solutions (−5°C), and a high concentration of salts are the factors facilitating sonoluminescence of the metal. Comparison with the characteristics of sonoluminescence of lanthanide ions studied earlier in the regimes of multibubble and single-bubble Sonolysis with a stationary bubble shows that the electron excitation of metal ions in the given case is associated with translational displacements of the bubble. Our results confirm the validity of the sonochemical model of microdroplet injection, which explains the penetration of nonvolatile salts into cavitation bubbles as a result of their deformation during intense movements.
B M Gareev - One of the best experts on this subject based on the ideXlab platform.
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confirmation of hydrated electrons formation during the moving single bubble Sonolysis activation of tb3 ion sonoluminescence by eaq acceptors in an aqueous solution
Journal of Photochemistry and Photobiology A-chemistry, 2020Co-Authors: G. L. Sharipov, B M Gareev, A. M. AbdrakhmanovAbstract:Abstract The acoustically excited (26 kHz, acoustic pressure of 1.34 bar) luminescence of Tb3+ ions in aqueous solutions of TbCl3 is activated by selective acceptors of hydrated electron ( e a q - ), namely H+, and Cd2+ ions and other, during the moving single-bubble Sonolysis. Sonoluminescence of Tb3+ is quenched when solvated electrons are present. The Tb3+ ions penetrate into the bubble across the liquid-gas interface, which is deformed during the bubble movement with the formation of microjets and nanodroplet injection. Then these ions are transferred to the electronically excited state upon inelastic collisions with particles having excess kinetic energy. The excited ions (*Tb3+, lifetime more than 400 μs) partly emit photons in the bubble and partly migrate to the solution, together with other Sonolysis products as a result of their ejection from a bubble into a liquid. In the solution, the *Tb3+ ions react with the radical products of H2O Sonolysis. The detected activation of the Tb3+ sonoluminescence is similar to the known activation of Tb3+ radioluminescence by e a q - acceptors (radiolysis generates e a q - together with *Tb3+). However, such activation is absent in the case of multibubble Sonolysis, for which *Tb3+ generation was established previously, but no e a q - was formed among the primary products of H2O Sonolysis (H and OH•). These facts indicate that acceptors suppress the reaction in which e a q - eliminates the excited state of the terbium ion *Tb3+ + e a q - → Tb2+. It is obvious considering the known redox potentials of the reactants. Consequently, hydrated electrons are generated in the moving single-bubble Sonolysis of water.
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electron stimulated luminescence of mathbf ru bpy _ mathbf 3 mathbf 2 in the Sonolysis of solutions of mathbf ru bpy _ mathbf 3 mathbf 2 and mathbf ru bpy _ mathbf 3 mathbf 3
Bulletin of The Russian Academy of Sciences: Physics, 2020Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, B M Gareev, L R YakshembetovaAbstract:The role of hydrated electrons in sonochemiluminescence (SCL) arising from the single- and multibubble Sonolysis of aqueous solutions of $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{2 + }}}}$$ and $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{3 + }}}}$$ is revealed. Possible chemiluminescent reactions between ruthenium ions and the products of water Sonolysis are considered. A conclusion is drawn concerning the previously unknown formation of eaq upon the single-bubble Sonolysis of water and the absence of this product upon multibubble Sonolysis.
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sonochemiluminescence of ru bpy 33 in aqueous solutions evidence of the formation of hydrated electrons during the single bubble Sonolysis in a neutral aqueous medium
Ultrasonics Sonochemistry, 2019Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, L R Yakshembetova, B M GareevAbstract:Abstract Consideration is given to single and multibubble sonochemiluminescence (SCL) in acidic Ru(bpy)33+ aqueous solutions due to the light emission of the excited ion *Ru(bpy)32+ at 613 nm. Spectrophotometrically controlled reduction of Ru(bpy)33+ to Ru(bpy)32+ occurs in both regimes of Sonolysis. The kinetics parameters of reduction under SCL during the multibubble Sonolysis do not depend on the H+ concentration in the solution (0.005 and 0.5 M H2SO4), but differ for the single-bubble Sonolysis. The intensity of single-bubble SCL is maximal at the beginning of Sonolysis and monotously decreases to the level of steady-state SCL after complete reduction of Ru(bpy)33+ to Ru(bpy)32+. The intensity of multibubble SCL at the beginning of Sonolysis is below the recognition threshold. Then it grows, passes through the maximum and also approaches the steady-state level after the reduction of ruthenium. By considering possible chemiluminescent reactions Ru(bpy)33+ + eaq → *Ru(bpy)32+, Ru(bpy)33+ + H → *Ru(bpy)32+ + H+, Ru(bpy)33+ + Ru(bpy)3+ → *Ru(bpy)32+ + Ru(bpy)32+ as well as the reactions of sonochemical formation of Ru(bpy)33+ and Ru(bpy)3+ from Ru(bpy)32+ and the reaction H+ + eaq → H, the conclusion is made about the generation of eaq during the single-bubble Sonolysis of water molecules. The presence and absence of eaq during the single and multibubble Sonolysis respectively explain the distinctions in the SCL kinetics. The evidence for the generation of eaq lies also in the reduction of the Fe(CN)63− ion observed during the single-bubble Sonolysis in the neutral solution, which is impossible without eaq. The yield of eaq is comparable to that of the hydrogen atom.
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spectroscopic measurement of electronic temperature in the bubbles during single and multibubble sonoluminescence of metal carbonyl solutions and nanodispersed suspensions
Ultrasonics Sonochemistry, 2019Co-Authors: G. L. Sharipov, B M Gareev, A. M. AbdrakhmanovAbstract:Abstract It is for the first time that we have obtained emission-line spectra of metal atoms during single-bubble sonoluminescence of metal carbonyl W(CO)6, Mo(CO)6, Cr(CO)6 solutions in dodecane and similar spectra during single- and multibubble sonoluminescence of nanodispersed Cr(CO)6 suspensions in water, 83% H2SO4 and 74% H3PO4. Nanodispersed suspensions with an average particle size of 15–20 nm were obtained through sonodispersing and filtering Cr(CO)6 crystals in water. The method for comparing the intensities of two atomic metal lines made it possible to measure the electronic temperatures achieved in cavitation bubbles under different modes of Sonolysis that vary in the range of (4.5–16)·103 K depending on the mode of Sonolysis, the type of liquid and saturating gas (He, Ar, Kr) and the acoustic energy entering the solution or suspension. The electronic temperature for multibubble sonoluminescence is, on the average, by (2–2.5)·103 K less than for single-bubble sonoluminescence for all liquids in question.
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luminescence of tb 3 and gd 3 ions in Sonolysis under the conditions of a single bubble moving in aqueous solutions of tbcl 3 and gdcl 3
Technical Physics, 2013Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, B M GareevAbstract:Luminescence bands of Tb3+ and Gd3+ ions are detected during Sonolysis in the regime of a moving single bubble in aqueous solutions of TbCl3 and GdCl3 salts with concentration 1–2 mol/L. Saturation with argon, low temperatures of solutions (−5°C), and a high concentration of salts are the factors facilitating sonoluminescence of the metal. Comparison with the characteristics of sonoluminescence of lanthanide ions studied earlier in the regimes of multibubble and single-bubble Sonolysis with a stationary bubble shows that the electron excitation of metal ions in the given case is associated with translational displacements of the bubble. Our results confirm the validity of the sonochemical model of microdroplet injection, which explains the penetration of nonvolatile salts into cavitation bubbles as a result of their deformation during intense movements.
A. M. Abdrakhmanov - One of the best experts on this subject based on the ideXlab platform.
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confirmation of hydrated electrons formation during the moving single bubble Sonolysis activation of tb3 ion sonoluminescence by eaq acceptors in an aqueous solution
Journal of Photochemistry and Photobiology A-chemistry, 2020Co-Authors: G. L. Sharipov, B M Gareev, A. M. AbdrakhmanovAbstract:Abstract The acoustically excited (26 kHz, acoustic pressure of 1.34 bar) luminescence of Tb3+ ions in aqueous solutions of TbCl3 is activated by selective acceptors of hydrated electron ( e a q - ), namely H+, and Cd2+ ions and other, during the moving single-bubble Sonolysis. Sonoluminescence of Tb3+ is quenched when solvated electrons are present. The Tb3+ ions penetrate into the bubble across the liquid-gas interface, which is deformed during the bubble movement with the formation of microjets and nanodroplet injection. Then these ions are transferred to the electronically excited state upon inelastic collisions with particles having excess kinetic energy. The excited ions (*Tb3+, lifetime more than 400 μs) partly emit photons in the bubble and partly migrate to the solution, together with other Sonolysis products as a result of their ejection from a bubble into a liquid. In the solution, the *Tb3+ ions react with the radical products of H2O Sonolysis. The detected activation of the Tb3+ sonoluminescence is similar to the known activation of Tb3+ radioluminescence by e a q - acceptors (radiolysis generates e a q - together with *Tb3+). However, such activation is absent in the case of multibubble Sonolysis, for which *Tb3+ generation was established previously, but no e a q - was formed among the primary products of H2O Sonolysis (H and OH•). These facts indicate that acceptors suppress the reaction in which e a q - eliminates the excited state of the terbium ion *Tb3+ + e a q - → Tb2+. It is obvious considering the known redox potentials of the reactants. Consequently, hydrated electrons are generated in the moving single-bubble Sonolysis of water.
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electron stimulated luminescence of mathbf ru bpy _ mathbf 3 mathbf 2 in the Sonolysis of solutions of mathbf ru bpy _ mathbf 3 mathbf 2 and mathbf ru bpy _ mathbf 3 mathbf 3
Bulletin of The Russian Academy of Sciences: Physics, 2020Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, B M Gareev, L R YakshembetovaAbstract:The role of hydrated electrons in sonochemiluminescence (SCL) arising from the single- and multibubble Sonolysis of aqueous solutions of $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{2 + }}}}$$ and $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{3 + }}}}$$ is revealed. Possible chemiluminescent reactions between ruthenium ions and the products of water Sonolysis are considered. A conclusion is drawn concerning the previously unknown formation of eaq upon the single-bubble Sonolysis of water and the absence of this product upon multibubble Sonolysis.
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sonochemiluminescence of ru bpy 33 in aqueous solutions evidence of the formation of hydrated electrons during the single bubble Sonolysis in a neutral aqueous medium
Ultrasonics Sonochemistry, 2019Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, L R Yakshembetova, B M GareevAbstract:Abstract Consideration is given to single and multibubble sonochemiluminescence (SCL) in acidic Ru(bpy)33+ aqueous solutions due to the light emission of the excited ion *Ru(bpy)32+ at 613 nm. Spectrophotometrically controlled reduction of Ru(bpy)33+ to Ru(bpy)32+ occurs in both regimes of Sonolysis. The kinetics parameters of reduction under SCL during the multibubble Sonolysis do not depend on the H+ concentration in the solution (0.005 and 0.5 M H2SO4), but differ for the single-bubble Sonolysis. The intensity of single-bubble SCL is maximal at the beginning of Sonolysis and monotously decreases to the level of steady-state SCL after complete reduction of Ru(bpy)33+ to Ru(bpy)32+. The intensity of multibubble SCL at the beginning of Sonolysis is below the recognition threshold. Then it grows, passes through the maximum and also approaches the steady-state level after the reduction of ruthenium. By considering possible chemiluminescent reactions Ru(bpy)33+ + eaq → *Ru(bpy)32+, Ru(bpy)33+ + H → *Ru(bpy)32+ + H+, Ru(bpy)33+ + Ru(bpy)3+ → *Ru(bpy)32+ + Ru(bpy)32+ as well as the reactions of sonochemical formation of Ru(bpy)33+ and Ru(bpy)3+ from Ru(bpy)32+ and the reaction H+ + eaq → H, the conclusion is made about the generation of eaq during the single-bubble Sonolysis of water molecules. The presence and absence of eaq during the single and multibubble Sonolysis respectively explain the distinctions in the SCL kinetics. The evidence for the generation of eaq lies also in the reduction of the Fe(CN)63− ion observed during the single-bubble Sonolysis in the neutral solution, which is impossible without eaq. The yield of eaq is comparable to that of the hydrogen atom.
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spectroscopic measurement of electronic temperature in the bubbles during single and multibubble sonoluminescence of metal carbonyl solutions and nanodispersed suspensions
Ultrasonics Sonochemistry, 2019Co-Authors: G. L. Sharipov, B M Gareev, A. M. AbdrakhmanovAbstract:Abstract It is for the first time that we have obtained emission-line spectra of metal atoms during single-bubble sonoluminescence of metal carbonyl W(CO)6, Mo(CO)6, Cr(CO)6 solutions in dodecane and similar spectra during single- and multibubble sonoluminescence of nanodispersed Cr(CO)6 suspensions in water, 83% H2SO4 and 74% H3PO4. Nanodispersed suspensions with an average particle size of 15–20 nm were obtained through sonodispersing and filtering Cr(CO)6 crystals in water. The method for comparing the intensities of two atomic metal lines made it possible to measure the electronic temperatures achieved in cavitation bubbles under different modes of Sonolysis that vary in the range of (4.5–16)·103 K depending on the mode of Sonolysis, the type of liquid and saturating gas (He, Ar, Kr) and the acoustic energy entering the solution or suspension. The electronic temperature for multibubble sonoluminescence is, on the average, by (2–2.5)·103 K less than for single-bubble sonoluminescence for all liquids in question.
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luminescence of tb 3 and gd 3 ions in Sonolysis under the conditions of a single bubble moving in aqueous solutions of tbcl 3 and gdcl 3
Technical Physics, 2013Co-Authors: G. L. Sharipov, A. M. Abdrakhmanov, B M GareevAbstract:Luminescence bands of Tb3+ and Gd3+ ions are detected during Sonolysis in the regime of a moving single bubble in aqueous solutions of TbCl3 and GdCl3 salts with concentration 1–2 mol/L. Saturation with argon, low temperatures of solutions (−5°C), and a high concentration of salts are the factors facilitating sonoluminescence of the metal. Comparison with the characteristics of sonoluminescence of lanthanide ions studied earlier in the regimes of multibubble and single-bubble Sonolysis with a stationary bubble shows that the electron excitation of metal ions in the given case is associated with translational displacements of the bubble. Our results confirm the validity of the sonochemical model of microdroplet injection, which explains the penetration of nonvolatile salts into cavitation bubbles as a result of their deformation during intense movements.
Elena Selli - One of the best experts on this subject based on the ideXlab platform.
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efficiency of 1 4 dichlorobenzene degradation in water under photolysis photocatalysis on tio2 and Sonolysis
Journal of Hazardous Materials, 2008Co-Authors: Elena Selli, C L Bianchi, C Pirola, G Cappelletti, V RagainiAbstract:Abstract The rate of 1,4-dichlorobenzene (1,4-DCB) degradation and mineralization in the aqueous phase was investigated either under direct photolysis or photocatalysis in the presence of commercial or sol–gel synthesized TiO2, or under Sonolysis at 20 kHz with different power inputs. Two lamps, both emitting in the 340–400 nm wavelength range with different energy, were employed as irradiation sources. Photocatalysis ensured faster removal of 1,4-DCB with respect to Sonolysis and direct photolysis. The highest degradation and mineralization rate was attained with the combined use of photocatalysis and Sonolysis, i.e. under sonophotocatalytic conditions. The efficiency of the employed advanced oxidation techniques in 1,4-DCB degradation is discussed also in relation to their energy consumption, which might be decisive for their practical application.
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mechanism and efficiency of atrazine degradation under combined oxidation processes
Applied Catalysis B-environmental, 2006Co-Authors: C L Bianchi, C Pirola, V Ragaini, Elena SelliAbstract:Abstract The mechanism of atrazine degradation in aqueous phase was investigated under Sonolysis at 20 kHz, ozonation, photolysis at 254 nm and photocatalysis in the presence of TiO2, employed either separately or in combination. Ozonation and photocatalysis induced atrazine de-alkylation, followed by slower de-chlorination, while direct photolysis at 254 nm produced very efficient de-chlorination. Simultaneous Sonolysis had beneficial effects on ozonation and photocatalysis, especially by increasing the rate of photocatalytic de-alkylation, and no effect on the unimolecular photolytic de-chlorination of atrazine. Although complete atrazine mineralization could not be attained, because of the stability of the s-triazine ring toward oxidation, atrazine degradation and overall detoxification, as related to the disappearance of chlorinated by-products, proceeded at the highest rate when photolysis at 254 nm was combined with ozonation.
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degradation of methyl tert butyl ether in water effects of the combined use of Sonolysis and photocatalysis
Ultrasonics Sonochemistry, 2005Co-Authors: Elena Selli, C L Bianchi, C Pirola, Marco BertelliAbstract:Abstract The degradation of methyl tert-butyl ether (MTBE) in water was kinetically investigated in a O2/Ar 80:20 atmosphere employing either Sonolysis at 20 kHz, or photocatalysis on TiO2 (with 315 nm
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synergistic effects of Sonolysis combined with photocatalysis in the degradation of an azo dye
Physical Chemistry Chemical Physics, 2002Co-Authors: Elena SelliAbstract:Photocatalysis and Sonolysis exhibit synergistic effects in the degradation of organic molecules in aqueous suspension, when low ultrasound frequency (i.e. 20 kHz) is employed. The degradation of the azo dye Acid Orange 8 in aqueous suspensions was systematically evaluated under Sonolysis, photocatalysis and sonophotocatalysis as a function of dye concentration, amount and type of photocatalyst (TiO2 or ZnO) and catalase addition, in terms of pseudo-first-order degradation rate constants. The evolution of hydrogen peroxide was also monitored. Synergistic effects of the combination of ultrasound and photocatalysis should mainly involve the aqueous phase and be due to an increased concentration of reactive radicals, consequent to the action of ultrasound on the peroxide species produced by both photocatalysis and Sonolysis.
David Skoloudik - One of the best experts on this subject based on the ideXlab platform.
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Sonolysis in risk reduction of symptomatic and silent brain infarctions during coronary stenting sonoreduce randomized controlled trial
International Journal of Cardiology, 2018Co-Authors: Dasa Viszlayova, Roman Herzig, Miroslav Brozman, Kateřina Langova, David SkoloudikAbstract:Abstract Background Silent brain infarcts can be detected on magnetic resonance imaging (MRI) in ~22% of patients after coronary angioplasty and stenting (CS). The effect of periprocedural Sonolysis on the risk of new brain infarcts during CS was examined. Methods Patients undergoing elective CS were allocated randomly to a bilateral Sonolysis group (70 patients, 58 men; mean age, 59.9 years) or a control group (74 patients, 45 men; mean age, 65.5 years). Neurologic examination, cognitive function tests, and brain MRI were performed prior to intervention and at 24 h after CS. Neurologic examination and cognitive function tests were repeated at 30 days after CS. Results No significant differences were observed in the number of patients with new infarcts (25.7 vs. 18.9%, P = 0.423), the number of lesions (1.3 ± 1.0 vs. 2.9 ± 5.3, P = 0.493), lesion volume (0.16 ± 0.34 vs. 0.28 ± 0.60 mL, P = 0.143), and the number of patients with new ischemic lesions in the insonated MCA territories (18.6vs. 17.6%, P = 0.958) between the Sonolysis group and the control group. There were no cases of stroke, transient ischemic attack, myocardial infarction, or death in the two groups. Intracranial bleeding was reported only in 1 patient in the control group (0 vs. 1.4%, P = 0.888). Clock-drawing test scores at 30 days were significantly higher in the Sonolysis group than in the control group (median 3.0 vs. 2.5, P = 0.031). Conclusions Sonolysis does not reduce the risk of new brain infarcts after CS. The effect of Sonolysis on number and volume of ischemic lesions and cognitive function should be assessed in further studies.
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Sonolysis in prevention of brain infarction during carotid endarterectomy and stenting sonobuster a randomized controlled trial
European Heart Journal, 2016Co-Authors: David Skoloudik, Martin Kuliha, Tomas Hrbac, Tomas Jonszta, Roman HerzigAbstract:Aims Previous case series have detected silent brain infarctions in as many as one-third of patients after carotid endarterectomy (CEA) and in up to two-thirds of patients after carotid angioplasty and stenting (CAS). Sonolysis employs ultrasound to facilitate disruption of thrombi and has been shown to be safe and effective for improving long-term outcomes following acute stroke. Here, we examined whether intraoperative Sonolysis alters the risk of new brain ischaemic lesions during CEA or CAS. Methods and results All consecutive patients with internal carotid stenosis ≥70% indicated for CEA/CAS were screened in this prospective study. Patients were allocated randomly to Sonolysis and control groups. Neurological examination, cognitive function tests, and brain magnetic resonance imaging (MRI) were conducted before intervention and at 24 and 30 days post-surgery. Of the 487 screened patients, 121 (87 males; mean age, 66.65 ± 7.17 years) were allocated to the Sonolysis group and 121 (75; 66.02 ± 8.11 years) to the control group. New brain ischaemic lesions on post-procedure MRI were significantly less frequent in the Sonolysis group than in the control group (31.4% of patients vs. 47.1%; P = 0.018). Sonolysis and CEA were identified as independent predictors of reduced brain ischaemic risk [Sonolysis: odds ratio (OR) = 0.450 (0.215–0.942), P = 0.034 and CEA: OR = 0.208 (0.087–0.495), P 0.3). Conclusion This study provides Class II evidence that Sonolysis during CEA or CAS reduces the risk of new brain ischaemic lesions. Clinical Trial Registration ([NCT01591005][1]). [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT01591005&atom=%2Fehj%2F37%2F40%2F3096.atom
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the role of Sonolysis and sonothrombolysis in acute ischemic stroke a systematic review and meta analysis of randomized controlled trials and case control studies
Journal of Neuroimaging, 2014Co-Authors: Maher Saqqur, David Skoloudik, Georgios Tsivgoulis, Francois Nicoli, V Sharma, Vincent Larrue, Jurgen Eggers, Fabienne Perren, Paris CharalampidisAbstract:OBJECTIVES To assess the evidence on the safety and efficacy of sonothrombolysis in acute stroke. SEARCH METHODS Electronic databases and grey literature were searched under different MeSH terms from 1970 to present. SELECTION CRITERIA Randomized control trials (RCTs) and case control studies (CCSs) on Sonolysis and sonothrombolysis alone or with microsphere in acute stroke patients (>18 old). Outcome measures included complete recanalization (CR) at 1-2 and 24 hours, 3 months modified Rankin Scale (mRS), and symptomatic intracerebral hemorrhage (sICH). Data was extracted to Review Manager software. RESULTS Fifty-seven studies were retrieved and analyzed. Ten studies (7 RCTs and 3 CCSs) were included in our meta-analysis, which revealed that Sonolysis and sonothrombolysis are safe (OR of sICH: 1.14; 95% confidence interval (CI): 0.56- 2.34;P=0.71) and effective (OR of CR at 1-2 hours: 2.95;95% CI: 1.81-4.81;P<0.00001) and have more than two-fold higher likelihood of favourable long-term outcome (3-month mRS 0-2; OR: 2.20; CI:1.52-3.19;P<0.0001). Further subgroup analysis based on the presence of microsphere revealed that it is safe (OR of sICH: 1.18; CI:0.433.24;P=0.75) and effective (OR of CR: 2.61; CI: 1.36-4.99;P=0.004). Subgroup analysis based on Sonolysis revealed to be safe and effective. CONCLUSIONS This novel treatment appears safe and effective. The evidence of microsphere as an enhancement of sonothrombolysis is evolving.
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safety and efficacy of endovascular Sonolysis using the ekosonic endovascular system in patients with acute stroke
American Journal of Neuroradiology, 2013Co-Authors: Martin Kuliha, Tomas Jonszta, Roman Herzig, Kateřina Langova, Martin Roubec, Jan Krajca, Daniel Czerny, Antonin Krajina, Vaclav Prochazka, David SkoloudikAbstract:BACKGROUND AND PURPOSE: Sonolysis is a new therapeutic procedure for arterial recanalization. The aim of this study was to confirm the safety and efficacy of endovascular Sonolysis by using the EkoSonic Endovascular System in subjects with acute ischemic stroke. MATERIALS AND METHODS: Patients with acute ischemic stroke with occlusion of the middle cerebral artery or basilar artery were enrolled consecutively in this prospective study. The control group (44 MCA and 12 BA occlusions) was selected from historical controls. EkoSonic Endovascular System was started within 8 hours after stroke onset. The NIHSS score at hospital admission, after 24 hours, and at 7 days; arterial recanalization; early neurologic improvement; symptomatic intracerebral hemorrhage; and favorable 3-month clinical outcome defined as a modified Rankin Scale score of 0–2 were evaluated by statistical means. RESULTS: Fourteen patients (10 men; mean age, 65.1 ± 11.2 years; median NIHSS score, 16.5) underwent EkoSonic endovascular Sonolysis. Arterial recanalization after endovascular treatment was achieved in 6 of 7 (85.7%) patients with MCA occlusion (4 complete recanalizations) and in all 7 (100%) patients with BA occlusion (6 complete recanalizations). No (0%) symptomatic intracerebral hemorrhage or periprocedural complications occurred. Seven (50%) patients were independent at 3 months (median mRS score, 2). Early neurologic improvement and favorable clinical outcome were significantly more frequent in patients with MCA occlusion undergoing EkoSonic endovascular Sonolysis than in controls (100% and 71.4% versus 4.6% and 13.6% of patients; P = .0001 and P = .003, respectively). Three-month mortality was significantly lower in patients with BA occlusion undergoing EkoSonic endovascular Sonolysis than in controls (0% versus 66.7% patients, P = .013). CONCLUSIONS: In this small study, EkoSonic endovascular Sonolysis allowed safe and potentially effective revascularization in patients experiencing acute ischemic stroke. BA : basilar artery cPTAS : combined percutaneous transluminal angioplasty and stenting mRS : modified Rankin Scale IAT : intra-arterial thrombolysis TICI : Thrombolysis in Cerebral Ischemia
