Rezumat
CZU 532.5: 537.58:537.84:538.3: 541.24
DOI https://doi.org/10.52577/eom.2022.58.1.41
The effects of electrical conductivity of magnetic fluids (MFls) are investigated both in the presence and in the absence of an external magnetic field (MF). It is shown that in MFls based on magnetite (Fe3O4) magnetic nanoparticles (MNPs) coated with the surfactant – oleic acid (OA), conductive ions are formed by OA molecules in both dissociation and electrochemical processes. The decisive role of electrochemical reactions of OA molecules on the surface of chemically active Cu electrodes, which form injection conductivity, has been proved. The analysis of the anisotropy of the MFl electrical conductivity in an external MF with chemically active and silent electrodes is given. An interpretation is presented of nonstationary ionic processes in the near-electrode layers which determine the kinetics of MNPs and autowaves in thin layers of MFLs.
Keywords: ion, dipole, polarization, dielectric constant, magnetic fluid, magnetic field, intensity, electric current, electrochemical reaction, injection of charges, ion waves.