Realization of Airy pattern acoustic bullets by depth of focus synthesis.

Energy concentration is a key parameter for the characterization of light or acoustic bullets. To the best of our knowledge, the highest encircled-energy ratio in the mainlobe reported is merely 25% for the solitary bullet waves and 30% for the nonsolitary bullet waves. This letter reports experimentally and theoretically on a new family of acoustic bullets, namely, Airy pattern ultrasonic bullets, realized by the depth of focus synthesis.

Visually controlled pulsatile release of insulin from chitosan poly-acrylic acid nanobubbles triggered by focused ultrasound.

Insulin therapy is the most effective way to control the blood glucose value of diabetic patients. The most effective administration route for insulin is subcutaneous injection because bioavailability for non-injection administration is low and unstable. However, patients often need a multiple daily insulin injection regimen to control basal and postprandial blood glucose, which causes various complications.

An ultrasensitive solid-state ECL biosensor based on synergistic effect between Zn-NGQDs and porphyrin-based MOF as "on-off-on" platform.

To develop an ultra-sensitive solid-state electrochemiluminescence (ECL) biosensor for detection of miRNA 24, three different forms of porphyrin metal-organic framework (MOF) nanomaterials with good biocompatibility were synthesized through small molecule ligand modulation. We investigated various properties of synthesized MOFs in the presence of different small molecule ligands. The as-obtained 2D MOF nanodisk exhibited high ECL intensity and outstanding stability in the presence of a co-reactant at low concentrations.

Wireless Power Transmission for Implantable Medical Devices Using Focused Ultrasound and a Miniaturized 1-3 Piezoelectric Composite Receiving Transducer.

Wireless power transmission (WPT) using ultrasound is a promising way for wirelessly recharging implantable medical devices (IMDs). However, the transmitted power using ultrasound so far is insufficient for driving the existing IMDs. Moreover, the size of the receiving transducer is larger, which is not suitable for implantation.

Fabrication of Lipid Nanotubules by Ultrasonic Drag Force.

This work reports a new method of fabricating lipid nanotubules using ultrasonic Stokes drag force in theory and experiment. Ultrasonic Stokes drag force generated using a planar piezoelectric ultrasonic transducer in a remotely controllable way is introduced. When ultrasonic Stokes drag force is applied on lipid vesicles, the lipid nanotubules attached can be dragged out from the lipid film.

Ultrasonic exposure parameters screening in permeability of mycobacterium smegmatis cytoderm induced by cavitation based on artificial neural network identification.

The low intensity ultrasound has been adopted by researchers to enhance the bactericidal effect against bacteria in vitro and in vivo. Although the mechanism is not completely understood, one dominant opinion is that the permeability increases because of acoustic cavitation. However, the relationship between ultrasonic exposure parameters and cavitation effects is not definitely addressed.

A rapid and non-invasive method for measuring the peak positive pressure of HIFU fields by a laser beam.

Based on the acousto-optic interaction, we propose a laser deflection method for rapidly, non-invasively and quantitatively measuring the peak positive pressure of HIFU fields. In the characterization of HIFU fields, the effect of nonlinear propagation is considered. The relation between the laser deflection length and the peak positive pressure is derived.

Optimal electrode shape and size of a few singly rotated quartz and langasite resonators.

Based on Mindlin's early work, we calculate and plot optimal electrode shape and size of Y-cut quartz, At-cut quartz, and Y-cut langasite plate thickness-shear resonators. The electrodes obtained are optimal in that they satisfy Bechmann's number in every direction. The results are useful in the design optimization of these resonators.

Nonlinear coupling between thickness- shear and thickness-stretch modes in a rotated Y-cut quartz resonator.

We point out an implication of the Poynting effect in nonlinear elasticity. It is shown that, due to the Poynting effect, thickness-stretch vibration can be induced in a plate thickness-shear mode resonator of rotated Y-cut quartz when the thickness-shear deformation is no longer infinitesimal. This nonlinear coupling is particularly strong when the frequency of the thickness-stretch mode is twice the frequency of the thickness-shear mode.

Effect of mass layer stiffness on propagation of thickness-twist waves in rotated Y-cut quartz crystal plates.

We analyze the effect of mass layer stiffness on thickness-twist waves propagating in a rotated Y-cut quartz crystal plate with thin mass layers on its surfaces. An equation that determines the dispersion relation of the waves is given and is solved numerically. Quantitative results of the effect of the mass layer stiffness on wave frequencies are presented.

Nonlinear behavior of electric power transmission through an elastic wall by acoustic waves and piezoelectric transducers.

Weakly nonlinear behavior of electric power transmission through an elastic wall by piezoelectric transducers and acoustic waves near resonance is studied based on the cubic theory of nonlinear electroelasticity. An approximate analytical solution is obtained. Output voltage is calculated and plotted.

Energy trapping in power transmission through an elastic plate by finite piezoelectric transducers.

We study transmission of electric energy through an elastic plate by acoustic wave propagation and piezoelectric transducers. Our mechanics model consists of an elastic plate with finite piezoelectric patches on both sides of the plate. A theoretical analysis using the equations of elasticity and piezoelectricity is performed.

Membrane analogy of the Stevens-Tiersten equation for essentially thickness modes in plate quartz resonators.

We show that the well-known Stevens-Tiersten equation for essentially thickness modes in doubly rotated quartz resonators is mathematically analogous to the equation governing the transverse motion of a pre-stretched elastic membrane resting on an elastic foundation. The implication of this analogy is that commercial finite element software for structural analysis can be used to solve the Stevens-Tiersten equation for resonators.

A thickness mode acoustic wave sensor for measuring interface stiffness between two elastic materials.

We studied thickness vibration of 2 elastic layers with an elastic interface mounted on a plate piezoelectric resonator. The effect of the interface elasticity on resonant frequencies was examined. The result obtained suggests an acoustic wave sensor for measuring the elastic property of an interface between 2 materials.

Vibration characteristics of a circular cylindrical panel piezoelectric transducer.

We study the theory of the basic vibration characteristics of a circular cylindrical shell piezoelectric transducer. The linear theory of piezoelectricity is used. Both the free-vibration solution for resonant frequencies and modes as well as the electrically forced-vibration solution for admittance are obtained.

Transmitting electric energy through a closed elastic wall by acoustic waves and piezoelectric transducers.

Transmission of electric energy through a closed elastic wall by piezoelectric transducers and acoustic waves is studied based on the linear theory of piezoelectricity and elasticity. A theoretical analysis is performed. For the structure and motion considered, the 3-D equations of linear piezoelectricity reduce to a 1-D mathematical problem.

On the eigenvalue problem for free vibrations of a piezoelectric/piezomagnetic body.

We present a systematic analysis of the eigenvalue problem associated with free, small-amplitude vibrations in an elastic body possessing piezoelectric, piezomagnetic, and magnetoelectric couplings. An abstract formulation is introduced. The operators in the abstract formulation are shown to be self-adjoint, from which a series of fundamental properties of resonant frequencies and vibration modes are proved concisely.