Synthesis and electric field response of titanium dioxide nano-particles dispersed in hydrophobic solvents.

We present a novel synthesis method for producing stable titanium dioxide nanoparticles (<10 nm) dispersed in hydrophobic solvents using organophosphates. Our approach enables the control of nanoparticles' electric field responsiveness by altering the dispersing medium's composition, expanding their potential applications in electronics, photovoltaics, and photocatalysis.

Remote Friction Reduction on Polystyrene Foam Surface by Focused Airborne Ultrasound.

In recent years, various tactile displays having the ability to change their surface friction have been proposed. These displays can express many types of textures and shapes that the materials used for them do not possess. In our study, we found that the ultrasound converged on the surface of polystyrene foam reduces the surface friction.

AUTD3: Scalable Airborne Ultrasound Tactile Display.

Through nonlinear effects, airborne ultrasound phased arrays enable mid-air tactile presentations, as well as auditory presentation and acoustic levitation. To create workplaces flexibly, we have developed a scalable phased array system in which multiple modules can be connected via Ethernet cables and controlled from a PC or other host device. Each module has 249 transducers and the software used can individually specify the phase and amplitude of each of the connected transducers.

Acoustical boundary hologram for macroscopic rigid-body levitation.

In previous studies, acoustical levitation in the far-field was limited to particles. Here, this paper proposes the "boundary hologram method," a numerical design technique to generate a static and stable levitation field for macroscopic non-spherical rigid bodies larger than the sound wavelength λ. This paper employs boundary element formulation to approximate the acoustic radiation force and torque applied to a rigid body by discretizing the body surface, which is an explicit function of the transducer's phase and amplitude.