Heat exchange systems, devices and methods are provided. One aspect of the invention relates to devices and systems for synthesizing ferrate at a site proximal to the site of use. A control cell associated with each actuator includes a register selectively stored with a desired pulse width. The operations of the temporarily deactivated ASIC block may be substituted for by appropriately programmed programmable logic. The ultrasonic apparatus for therapeutical use is provided with a belt wearable in a position that surrounds a diseased part and unit ultrasonic radiators can be mounted in an arbitrary position of the belt.