Effect of acoustic cavitation phenomenon on bioactive compounds release from Eryngium caucasicum leaves

In Polishing Process based on Vibration of Liquid (PVL), abrasive particles driven by polishing liquid will brush and etch workpiece to achieve material removal. Because the liquid is vibrated in ultrasonic frequency, polishing process will be greatly affected by cavitation phenomenon. The critical thermal conditions and high-speed liquid jet produced by bubble dynamics may damage workpiece. A refined Dissipative Particle Dynamics method is applied to study the effect of acoustic cavitation on PVL. Validity of the numerical simulation is tested according to experimental results.

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Synthesis and Characterization of ZnO Nanoparticles

MRS Proceedings ◽

10.1557/proc-829-b2.27 ◽

2004 ◽

Vol 829 ◽

Cited By ~ 2

Author(s):

I. U. Abhulimen ◽

X. B. Chen ◽

J. L. Morrison ◽

V. K. Rangari ◽

L. Bergman ◽

...

Keyword(s):

Blue Shift ◽

Acoustic Cavitation ◽

Spherical Particles ◽

Synthesis And Characterization ◽

Electrical Measurements ◽

Cavitation Phenomenon ◽

Transmission Electron ◽

Significant Blue Shift ◽

Scanning Electron

ABSTRACTNanoparticles of ZnO were synthesized using a sonochemical technique. Sonochemistry arises from an acoustic cavitation phenomenon, that is, the formation, growth and implosive collapse of bubbles in a liquid medium. The ultraviolet photoluminescence (PL) studies of the samples showed a strong PL intensity and a significant blue shift relative to the PL of the bulk. Shifts up to 70 meV were observed and attributed to a confinement effect. Scanning electron microscopy indicated roughly spherical particles, ∼160 nm in diameter. However, nano-platelets and rods were observed in transmission electron micrographs. Preliminary electrical measurements indicated a highly resistive nature of the nanoparticulate material.

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A Condition Monitoring for Collapsing Bubble Mechanism for Sonoluminescence and Sonochemistry

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4029679 ◽

2015 ◽

Vol 7 (2) ◽

Cited By ~ 1

Author(s):

Ali Alhelfi ◽

Bengt Sundén

Keyword(s):

Acoustic Waves ◽

Bubble Dynamics ◽

Stokes Equations ◽

Current Model ◽

Computation Time ◽

Acoustic Cavitation ◽

Full Potential ◽

Bubble Oscillation ◽

Cavitation Phenomenon ◽

Wide Range

The acoustic cavitation phenomenon is a source of energy for a wide range of applications such as sonoluminescence and sonochemistry. The behavior of a single bubble in liquids is an essential study for acoustic cavitation. The bubbles react with the pressure forces in liquids and reveal their full potential when periodically driven by acoustic waves. As a result of extreme compression of the bubble oscillation in an acoustic field, the bubble produces a very high pressure and temperature during collapse. The temperature may increase many thousands of Kelvin, and the pressure may approach up to hundreds of bar. Subsequently, short flashes can be emitted (sonoluminescence) and the high local temperatures and pressures induce chemical reactions under extreme conditions (sonochemistry). Different models have been presented to describe the bubble dynamics in acoustic cavitation. These studies are done through full numerical simulation of the compressible Navier–Stokes equations. This task is very complex and consumes much computation time. Several features of the cavitation fields remain unexplained. In the current model, all hydrodynamics forces acting on the bubble are considered in the typical solution. Bubble oscillation and its characteristics under the action of a sound wave are presented in order to improve and give a more comprehensive understanding of the phenomenon, which is considered to have a significant role in different areas of science and technology.

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