In this study, we investigated a method for the non-destructive detection of cracks based on an ultrasonic transit timing method. This method is considered to be an effective means for crack monitoring over an extensive coverage area. Aluminum specimens were prepared with a range of crack sizes and subjected to a tone burst wave to investigate the relationship between crack depth and the transi...

Air-coupled ultrasonic inspection using leaky Lamb waves offers attractive possibilities for non-contact testing of plate materials and structures. A common method uses an air-coupled pitch-catch configuration, which comprises a transmitter and a receiver positioned at oblique angles to a thin plate. It is well known that the angle of incidence of the ultrasonic bulk wave in the air can be used...

This paper considers the detection of symmetric crack-like defects in thin metallic plates using longitudinal ultrasonic waves. Only physically small defect sizes are considered in order that the initial stages of crack growth, for example during fatigue, can be detected. This method has the potential to be significantly faster for non-destructively detecting defects than conventional ultrasoni...

Medical plants are adapted to different kinds of dormancy to survive in the worst situations. Regarding to ecological viewpoint, this kind of adaptation is very important in respect to restriction of genetic draft and decrease of genetic resource of medicinal plants. This leads to plant survival even after prolonged drought. Since some of them are endangered species and in the other hand increa...

continuous exposure to high-energy ultrasonic waves depolymerises macromolecules in solutions and produces a permanent reduction in viscosity. different factors affect the efficiency of this ultrasonic depolymerisation. in this work ultrasonic degradation of one commercially important hydrogel based on acrylic acid and acrylamide was carried out in aqueous solution at room temperature (25oc). a...

In part 21 of the tutorial series "Acoustofluidics--exploiting ultrasonic standing wave forces and acoustic streaming in microfluidic systems for cell and particle manipulation", we review applications of ultrasonic standing waves used for enhancing immunoassays and particle sensors. The paper covers ultrasonic enhancement of bead-based immuno-agglutination assays, bead-based immuno-fluorescenc...

Simultaneous measurements of laser excited ultrasonic waves in a solid sample and in the surrounding air were used for characterizing the plasma shielding effect and for the evaluation of its influence in optoacoustic measurements. Typical modifications of ultrasonic waves are discussed and the acoustic energy distribution between the solid and the atmosphere is assessed by a comparative analys...

Mice produce ultrasonic vocalizations (USVs) in a variety of social contexts throughout development and adulthood. These USVs are used for mother-pup retrieval1, juvenile interactions2, opposite and same sex interactions3,4,5, and territorial interactions6. For decades, the USVs have been used by investigators as proxies to study neuropsychiatric and developmental or behavioral disorders7,8,9, ...

Bulk and Rayleigh (or surface wave) velocities of ultrasonic waves in chromium coatings on steel were measured and an experimental correlation was found between the surface velocity and the hardness. Since qualitative coating evaluation is commonly made using hardnesses as a guideline, the possibility is herewith presented of using the so und velocities of surface ultrasonic waves for this purp...

In this paper, the effect of ultrasonic pre-treatment and aeration on the flotation separation of chalcopyrite from pyrite was investigated at different amounts of potassium ethyl xanthate (KEX), as a collector, and pH values. Artificially-mixed samples of chalcopyrite and pyrite were subjected to flotation studies to understand the effect of aeration with or without ultrasonic tre...