Friction and wear are detrimental to engineered systems. Ultrasonic lubrication is achieved when the interface between two sliding surfaces is vibrated at a frequency above the acoustic range (20 kHz). As a solid-state technology, ultrasonic lubrication can be used where conventional lubricants are unfeasible or undesirable. Further, ultrasonic lubrication allows for electrical modulation of th...

PURPOSE To assess whether a combined treatment of low-frequency (25 kHz) ultrasonic-debridement systems followed by vacuum-assisted wound closure (VAC) produces a better outcome in deep sternal wound infections (SWIs) compared to that of VAC alone. METHODS We evaluated 45 consecutive patients (25 males) between January 2013 and December 2016, in whom deep SWI was treated with a combination of...

Background and objectives: Colchicum kurdicum (Bornm.) Stef. is a flowering perennial monocotyledon plant that has many important bioactive compounds especially colchicine and colchicine derivatives. In this study, the ultrasound-assisted acidic-solvent extraction method coupled with response-surface method was presented as the successful method for large scale extract...

Ultrasonic energy is widely used in wire bonding for microelectronics packaging. It is necessary to ensure that the maximum ultrasonic vibration displacement occurs at or near the tip of the bonding tool (capillary) for optimal performance. In this study, amplitude profiles of ultrasonic vibrations along capillaries were measured with load using a laser interferometer. This provided valuable in...

background: ultrasonic vibrations are used to remove a cemented post from a root canal requiring endodontic retreatment. various results have been reported from the studies that evaluated the effect of ultrasonic instruments in removing the posts cemented with resin cements. the aim of this study was to evaluate the effect of ultrasonic energy on the retention of prefabricated metal post cement...

Sound attenuation and internal friction coefficients are calculated for a realistic model of amorphous silicon. It is found that, contrary to previous views, thermal vibrations can induce sound attenuation at ultrasonic and hypersonic frequencies that is of the same order or even larger than in crystals. The reason is the internal-strain induced anomalously large Grüneisen parameters of the low...

Sound attenuation and internal friction coefficients are calculated for a realistic model of amorphous silicon. It is found that, contrary to previous views, thermal vibrations can induce sound attenuation at ultrasonic and hypersonic frequencies that is of the same order or even larger than in crystals. The reason is the internal strain induced anomalously large Grüneisen parameters of the low...

A study is presented of a miniature ultrasonic surgical drill designed for bone biopsy, based on an ultrasonic/sonic drill which converts high frequency to low frequency vibrations through a freely vibrating mass between an ultrasonic transducer-horn and a drill bit. For conventional surgical drilling using a rotary drill or an ultrasonic drill, considerable power is required to penetrate into ...