In the manufacturing of micro/nanocomposite materials, micro/nanoparticles need to be dispersed evenly into the base materials. However, due to their high surface-to-volume ratio and high surface energy, the micro/nanoparticles tend to agglomerate and cluster together. Ultrasonic cavitation is effective to disperse micro/nanoparticles. However, works on correlating the cavitation parameters wit...

background and objectives: colocynthin is the major active secondary metabolite of colocynth, citrullus colocynthis (l.) schrad, which has been used in traditional and ethno medicine of many countries.  it could be considered as an active marker for quality control of colocynth and its herbal products. analysis and standardization of colocynth and its herbal preparations are a critical issue fo...

Recently, the Al2O3–TiO2–ZrO2 system has found valuable applications, particularly, as a support for NOx storage–reduction (NSR) catalysts. Nanocomposite powders were prepared from the co-precipitation method in inorganic precursors. The behaviors of mixed oxide nanoparticles under ultrasonic irradiation, such as dispersion, and crushing were studied. Phase transformations, crystallite size, an...

In this paper, ultrasonic wave propagation in three phases (3P) of composite materials was investigated. The simulation was conducted by PZFlex analysis code, a time domain finite element program. The reflection and transmission characteristics with different shapes of middle layer between glass fiber and epoxy resin are investigated in order to understand basic ultrasonic behavior of energy di...

For meaningful assessment of results from laboratory and pilot plant trials, it is often necessary to know the mixing characteristics within the ultrasonic reactors. Previous workers have used conductivity measurements in an attempt to characterize the residence time distribution in ultrasonic reactors, but these results do not provide direct data on the mixing within the high power region adja...

An ultrasonic technique was used to study the changes of the rheological properties of dough during fermentation at 37C and compared with the ertensional properties of fermented dough obtained from tensile tests carried out in a Universal Testing Machine. The velocity and attenuation of a longitudinal wave (P-wave) propagated through the dough samples were measured and analyzed to obtain the vi...

Ultrasonic guided waves are used to detect the delamination between skin and honeycomb of a composite helicopter rotor blade. Theoretical work is carried out for guided waves in the trailing edge of a rotor blade, which is a multilayer composite skin/NOMEX half space structure. The dispersion relation is obtained with the global matrix method. Theoretically driven experiments are conducted on a...

recently, the al2o3–tio2–zro2 system has found valuable applications, particularly, as a support for nox storage–reduction (nsr) catalysts. nanocomposite powders were prepared from the co-precipitation method in inorganic precursors. the behaviors of mixed oxide nanoparticles under ultrasonic irradiation, such as dispersion, and crushing were studied. phase transformations, crystallite size, an...

Due to the problems of dispersion and multi-modes overlap for ultrasonic Lamb wave propagation, it is difficult to use it in many fields, such as long-range inspection. After ultrasonic Lamb waves are generated by a broadband ultrasonic pulse, these problems make the wave packets to spread out and various modes overlap in both time and space domain as they propagate through a plate or pipe. It ...