In the present study, stable homogeneous graphene nanoplatelet (GNP) nanofluids were prepared without any surfactant by high-power ultrasonic (probe) dispersion of GNPs in distilled water. The concentrations of nanofluids were maintained at 0.025, 0.05, 0.075, and 0.1 wt.% for three different specific surface areas of 300, 500, and 750 m2/g. Transmission electron microscopy image shows that the...

Based on the thermoelastic mechanism of laser ultrasonic, the problems of the thermal conduction and the coupling between the motion of solid and fluid are solved by using the finite element method. And then the transient waveforms of leaky Lamb waves induced by pulse laser action on the air-aluminum interface are obtained. Experimental signals of laser-induced leaky Lamb waves at the air-alumi...

The picosecond correlation technique has been used to study the generation and detection of ultrasonic strain waves in polythiophene thin films, in the range of 0.3-19 6Hz. We show that the strain generation is mainly due to thermal expansion following energy relaxation associated with exciton formation and that the spectral dependence of the strain response is proportional to ja(tv)/&tv, the f...

In this study, the Er:YAlO3 as up-conversion luminescence agent, which can transfer the visible light part in the sonoluminescence to ultraviolet light, was synthesized by nitrate–citrate acid and sol–gel method. And then the Er:YAlO3/TiO2–Fe2O3 composite as a sonocatalyst was prepared by ultrasonic dispersion and liquids boil method. The prepared Er:YAlO3/TiO2–Fe2O3 composite was characterized...

A n experimental investigation of a solid–liquid dispersion pipe flow was conducted using a pulsed ultrasonic Doppler velocimeter. The solid phase was composed of buoyant particles dispersed in water. This particular two-phase flow was used to mimic the behaviour of ice–water flow. Four diagnostics were used to study the complex nature of the two-phase flow mixtures: mean velocity profiles, spa...

Graphitic-C3N4(g-C3N4), a low-cost visible-light-driven photocatalyst, was used for the photocatalytic oxidation of aqueous methylene blue (MB) in the dark with Sr4Al14O25:(Eu,Dy) assistance. The Sr4Al14O25:(Eu,Dy)/g-C3N4 photocatalysts were fabricated through the ultrasonic dispersion method. The commercial Sr4Al14O25:(Eu,Dy) phosphor was used as a long afterglow supplier for exciting g-C3N4 i...

Abstract A model-based algorithm is presented that uses minimal a priori information and assumptions to adaptively estimate parameters associated with propagating waves in a homogeneous medium. These parameters include transmitter and receiver transfer functions, propagation distances, dispersion, and propagation loss. The algorithm is described in a general framework that accommodates direct a...