Abstract: The invention relates to a jet mill comprising a milling chamber with a longitudinal axis, an inlet at one end of the axis and an outlet at the opposite end of the axis, the milling chamber comprising a multitude of pins arranged in the free flow cross-section of the milling chamber, wherein the pins are arranged in at least two planes perpendicular to the longitudinal axis, the planes being distant to each other in the longitudinal direction, and the pins of one plane being laterally offset to the pins of the subsequent plane, wherein the milling chamber is divided into alternate pin segments and acceleration segments, the pin segments each having at least two planes of pins, and the acceleration segments having no pins.

Abstract: A method of generating at least one encryption key (130) for encrypting data (142), a method of 5 data transmission between at least two communication systems (136, 138), a method of encrypting data (142) and a method of decrypting encrypted data (144) are disclosed. Further disclosed are an encryption key generating device (110), a system (134), a data encryption system (148) and a data decryption system (150). The method of generating at least one encryption key (130) for encrypting data (142), specifically for data transmission over an insecure channel, comprises: i. blending at least two materials (114) according to at least one item of blending in-formation by using a blending device (112), thereby generating at least one blend (120); ii. detecting at least one material property (124) of the blend (120) by using at least one detector (126); and iii.