Acoustic droplet vaporization and inertial cavitation thresholds and efficiencies of nanodroplets emulsions inside the focused region using a dual-frequency ring focused ultrasound

作者：Xu, Shanshan; Chang, Nan; Wang, Rui; Liu, Xiaodong; Guo, Shifang; Wang, Supin; Zong, Yujin^*; Wan, Mingxi^*

来源：Ultrasonics Sonochemistry, 2018, 48: 532-537.

DOI：10.1016/j.ultsonch.2018.07.020

• Acoustic droplet vaporization
• Dual frequency insonication
• Threshold
• Focal zone
• Inertial cavitation

In this work, in order to develop a low-acoustic-intensity, high-efficiency and precise-treatment strategy, the vaporization of droplets and the inertial cavitation of vaporized microbubbles, using a dual-frequency focused ultrasound transducer, were investigated. The effect of a low frequency (LF), 1.1-MHz, sonication on droplet vaporization and the following inertial cavitation by the introduction of a high frequency (HF), 5-MHz, sonication was studied. It is shown that acoustic droplet vaporization (ADV) threshold is the lowest at dual-frequency sonication (LF of 18.9 W/cm(2) and HF of 4.1 W/cm(2)); moreover, the ADV efficiency is the highest at intensity threshold. The ADV area can be minimized to 2 mm(2) using a dual-frequency sonication (LF of 38.1 W/cm(2) and HF of 8.5 W/cm(2)). The IC area and efficiency can also be modulated using a dual-frequency sonication. Consequently, it can be concluded that in contrast to the single-frequency sonication, using the dual-frequency ultrasound, the vaporization of nanodroplets and the following inertial cavitation of the vaporized microbubbles can be modulated. Besides, a dual-frequency can result in the minimum ADV/IC area, lowest ADV/IC threshold, and highest ADV/IC efficiency.

• 出版日期2018-11
• 单位西安交通大学