Adam Brotchie

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Acoustic bubble-size distributions have been determined using a pulsed ultrasound method at different ultrasound powers and frequencies. It was observed that the mean bubble size increased with increasing acoustic power and decreased with increasing ultrasound frequency. It was also recognized that the mean size of bubbles emitting sonoluminescence was(More)
The multibubble sonoluminescence (MBSL) intensities from water exposed to the simultaneous ultrasonic irradiation from 20 kHz (fixed at 6.3 W) and 355 kHz (variable power) ultrasound sources have been compared to the MBSL from the individual ultrasound sources under the same power conditions. A synergistic enhancement of the sonoluminescence (SL) signal,(More)
For the first time, we apply a high-speed imaging technique to record the activity of acoustically driven cavitation bubbles (86 kHz) on micropatterned surfaces with hydrophobic and hydrophilic stripes. The width of the hydrophobic stripes lies between 3.5 and 115 μm. This work provides the first direct visualization of the preferential location of bubbles(More)
A comparison between the temperatures within imploding acoustic cavitation bubbles and the extent of sonoluminescence (SL) quenching by C(1)-C(5) aliphatic alcohols in 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO(4)], a well known imidazolium based room temperature ionic liquid (RTIL)), has been made at an ultrasound frequency of 213 kHz. The(More)
Acoustic bubble sizes, coalescence behavior, and sonochemical activity have been investigated in water in the presence of various electrolyte additives (KCl, HCl, and NaNO(3)) and saturating gases-helium, air, and argon. A strong correlation was identified between the bubble radius and the dissolved gas concentration in the cavitation medium. The extent of(More)
Various fundamental properties of acoustic cavitation bubbles have been investigated in single- and dual-frequency sound fields. It was found that the relative extent of bubble coalescence in the dual-frequency field correlated strongly with the synergistic enhancement of the sonochemical reaction rates. Both the relative extent of coalescence and the(More)
High-speed photographic observations of cavitation occurring under a low-frequency (21 kHz) sonotrode tip in the presence of an additional, high-frequency (355 kHz) ultrasound source have been made in water and in dilute aqueous solute solutions. Acoustic emission spectra were measured to support the visual observations. It was seen that a nucleating effect(More)
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