Coil-Only High-Frequency Lamb Wave Generation in Nickel Sheets.

This study presents a novel, coil-only magnetostrictive ultrasonic detection method that operates effectively without permanent magnets, introducing a simpler alternative to conventional designs. The system configuration is streamlined, consisting of a single meander coil, an excitation source, and a nickel sheet, with both the bias magnetic field and ultrasonic excitation achieved by a composite excitation containing both DC and AC components. This design offers significant advantages, enabling high-frequency Lamb wave generation in nickel sheets for ultrasonic detection while reducing device complexity.

Bottom Crack Detection with Real-Time Signal Amplitude Correction Using EMAT-PEC Composite Sensor.

During electromagnetic ultrasonic testing, it is difficult to recognize small-size bottom cracks by time of flight (ToF), and the lift-off fluctuation of the probe affects the accuracy and consistency of the inspection results. In order to overcome the difficulty, a novel composite sensor of an electromagnetic acoustic transducer (EMAT) and pulse eddy current (PEC) is designed. We use the amplitude of a bottom echo recorded by EMAT to identify the tiny bottom crack as well as the amplitude of PEC signals picked up by the integrated symmetric coils to measure the average lift-off of the probe in real time.

Ultrasonic detection method based on flexible capillary water column arrays coupling.

Conventional water immersion ultrasonic testing faces limitations due to factors such as environmental conditions, workpiece dimensions, corrosion, and resource wastage. Contact-based coupling methods, which employ coupling media or specific coupling structures, offer a convenient approach to coupling acoustic waves and reduce signal attenuation. However, these methods are time-sensitive and lack adaptability to uneven surfaces, particularly when dealing with workpieces featuring subtle undulations, resulting in significant signal decay.

Catechin as a new improving agent for a photo-Fenton-like system at near-neutral pH for the removal of inderal.

Photodegradation of inderal in a photo-Fenton like system at near-neutral pH modified with catechin, a natural catecholate siderophore, was investigated under simulated sunlight. The main factors influencing the process, such as Fe(iii)-catechin complexes, pH, and catechin concentration were examined. Photodegradation of inderal was strongly dependent on pH, following the order pH 3.