Refined secondary Bjerknes force equation for double bubbles with pulsation, translation, and deformation.

The secondary Bjerknes force (SBF) is the time-averaged interaction between two bubbles driven in a sound field. We derived a refined formula for the interaction force, incorporating the radial vibration and translational and deformational motions of the bubble. The coupling of pulsation, translation, and deformation enhances the interaction between bubbles but also weakens their stability, making it easier for bubbles to merge or break during motion.

Dynamics of three cavitation bubbles with pulsation and symmetric deformation.

A new system of dynamical equations was obtained by using the perturbation and potential flow theory to couple the pulsation and surface deformation of the second-order Legendre polynomials (P) of three bubbles in a line. The feasibility and effectiveness of the model were verified by simulating the radial oscillations, surface deformation with P, and shape evolution of three bubbles. The spherical radial pulsation and surface deformation of the three bubbles exhibit periodic behavior.

Dynamics of twin bubbles formed by ultrasonic cavitation in a liquid.

Based on potential flow and perturbation theory, a theoretical model is derived to describe the pulsation, translation, and deformation of twin bubbles in an ultrasound field. The amplitudes of radial oscillation, translation, and deformation of twin bubbles are found to depend on initial translation velocities. The radii, translation, and deformation of twin bubbles also exhibit periodic behavior.

[Recognition of S1 and S2 heart sounds with two-stream convolutional neural networks].

Auscultation of heart sounds is an important method for the diagnosis of heart conditions. For most people, the audible component of heart sound are the first heart sound (S1) and the second heart sound (S2). Different diseases usually generate murmurs at different stages in a cardiac cycle.

Controllable and reversible sensing cyanide ion using dual-functional Cu(II)-based ensemble.

In this work, a dual-functional Cu-based ensemble (2S·Cu) was well designed and characterized. Then, the successional and discriminating sensing for CN over other competitive species (HPO and biothiols) was achieved based on the disaggregation of 2S·Cu ensemble and the deprotonation of imidazole NH of regenerated sensor S in aqueous solution, respectively. The visual sensing mechanism could be clearly demonstrated by H NMR, HRMS and energy changes between the HOMO-LUMO band gaps.

Tb(III) line intensities in multibubble sonoluminescence.

We observed the line emissions of trivalent terbium [Tb(III)] ions during multibubble sonoluminescence (MBSL) in the aqueous solutions of terbium chloride (TbCl) under argon gas atmosphere. The line intensities of excited Tb(III) ions increased with TbCl concentration(mass percentage) in aqueous solutions. This phenomenon was interpreted qualitatively by numerically computing the Tb(III) line intensities in one sonoluminescing bubble among the cavitation bubbles in a liquid.

Computational investigation of Tb(III) ion line intensities in single-bubble sonoluminescence.

We perform a computational fluid dynamics simulation of trivalent terbium [Tb(III)] ion line emissions from single-bubble sonoluminescence (SBSL). Our simulation includes dynamic boundary conditions as well as the effects of gas properties and quenching by species, such as nitrite ion (NO_{2}^{-}). Simulation results demonstrate that when the maximum temperature inside a dimly luminescing bubble is relatively low, emission peaks from excited Tb(III) ions are prominent within the emission spectra.

Publisher's Note: Asymmetric transmission of sound wave in cavitating liquids [Phys. Rev. E 95, 033118 (2017)].

This corrects the article DOI: 10.1103/PhysRevE.95.

Asymmetric transmission of sound wave in cavitating liquids.

Two modes of the asymmetric sound transmission are observed experimentally in a one-dimensional system composed of coupled two layers of liquids. Their cavitation thresholds are different from each other. When the sound wave propagates from the high-threshold liquid to the low-threshold liquid, the two liquids can avoid the cavitation for a medium driving pressure.

Dynamics of two interacting bubbles in a nonspherical ultrasound field.

In this paper, we present and analyze a model of the oscillations of a pair of gas bubbles driven by nonspherical ultrasound. We derived our model based on the perturbation and potential flow theories and use it to study three cases of oscillation of two bubbles under driving ultrasound with different initial phases, different separation distances between the bubbles and different sound pressure amplitudes. For the driving ultrasound with different initial phases, we obtain the in-phase and anti-phase radial pulsations of the bubbles in incompressible liquid.