Figure 2
From: Ultrasonic actuation of a fine-needle improves biopsy yield
(A) \(30 \, {\upmu }\text {m}\) diameter polystyrene microparticles were used to visualize the water flow pattern around the needle during sonication. The graph represents the time-averaged velocity field of the particles, calculated across a time window of 100 ms. (B) Schlieren images show the disturbance of water laminar flow induced by the needle action as a demonstration of acoustic streaming taking place around the needle tip during sonication. (C) The droplet size distribution was controlled with ultrasonic driving frequencies and followed the theoretical relationship. This is exemplified in HS imaging (D), which revealed micro-droplet ejections of water at different driving frequencies from a main water drop hanging from the needle when the needle was operated in air. (A,B) The results demonstrate the capability of SonoLancet to induce mass transfer as well as (C,D) controlling the size of atomized droplets. On each box, the central mark represents the median, and the lower and upper edges of the box indicate the 25th and 75th percentiles, respectively. The whiskers extend to the most extreme values of the data set excluding the outliers, and the outliers are plotted individually with non-filled circles.
