High-voltage pulse rise time decreasing using transmission coaxial and spiral lines with ferrite

This article presents the results of a study of the formation of a short rise time of a powerful nanosecond 410 kV pulse. Ferrite filled coaxial transmission lines with standard inner conductor and construction in the form of a spiral are designed. The sharpening of the pulse occurs due to the appearance of an electromagnetic shock wave in the ferrite. The value of the rise time at the level of 0.1 - 0.9 has been decreased from 4.5 to 2.5 ns.

Development of an Omnidirectional-Capable Electromagnetic Shock Wave Generator for Lipolysis

Traditional methods for adipose tissue removal have progressed from invasive methods such as liposuction to more modern methods of noninvasive lipolysis. This research entails the development and evaluation of an omnidirectional-capable flat-coil electromagnetic shock wave generator (EMSWG) for lipolysis. The developed EMSWG has the advantage of omnidirectional-capable operation. This capability increases the eventual clinical usability by adding three designed supports to the aluminum disk of the EMSWG to allow omnidirectional operation. The focal pressures of the developed EMSWG for different operating voltages were measured, and its corresponding energy intensities were calculated. The developed EMSWG was mounted in a downward orientation for lipolysis and evaluated as proof of concept. In vitro tests on porcine fatty tissues have been carried out. It is found that at a 6 kV operating voltage with 1500 shock wave exposures, a 2 cm thick subcutaneous hypodermis of porcine fatty tissue can be ruptured, resulting in a damaged area of 1.39 mm2. At a 6.5 kV operating voltage with 2000 shock wave exposures, the damaged area is increased to about 5.20 mm2, which can be enlarged by changing the focal point location, resulting in significant lipolysis for use in clinical applications.