Process for the charging of a catalyst and for the running of a reactor in which reactions take place in multiphase systems, wherein a gaseous phase prevalently consisting of CO and H2 is bubbled into a suspension of a solid in the form of particles in a liquid, according to the Fischer-Tropsch technology. In one embodiment, hard magnetic layers are disposed in contact with the free layer outside of and separated from the MTJ stack active region by a thick dielectric layer. The sources are activated in accordance with an activation profile in order to calibrate or otherwise test the sensor. The discrete wavelet signals are analyzed at multiple DOM tree resolution levels.