Design of Longitudinal-Torsional Transducer and Directivity Analysis during Ultrasonic Vibration-Assisted Milling of Honeycomb Aramid Material.

This paper presents a longitudinal-torsional transducer for use during the ultrasonic vibration-assisted milling (UVAM) of honeycomb aramid material. The mechanism of longitudinal-torsional conversion was analyzed to guide the design of a vibration transducer. The transducer features five spiral grooves around the front cover plate, which function under the excitation of a group of longitudinal piezoelectric ceramics.

[Treatment of aortic arch aneurysm with graftstent by endovascular surgery].

Objective: To study the feasibility of treatment of aortic arch aneurysm with graftstent by intravascular surgery.

Methods: Animal model of aortic arch aneurysm was established using 10 piglets. An aortic arch-shaped graftstent was transferred and implanted to the site of aortic arch aneurysm through femoral artery under angiography.