will be a pure magnetic relaxation process, and for τ ≫ tm, there will be a blocking of the magnetic moments of the nanop. Between the two cases, there will be a magnetic drag.
In the alternating magnetic field (harmonic), magnetic relaxation processes lead to a heating of nanoparticles, an effect with applications in biomedicine such as in the alternative therapy of tumors by magnetic hyperthermia. Also, the rapid response of nanoparticles to the application of an external magnetic field makes them easy to manipulate, with application in target medication and drug delivery. In addition, in biomedicine, the magnetic nanoparticles are also used as contrast agents in magnetic resonance imaging (MRI) based on two essential characteristics of nanoparticles: their magnetism and small size.
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