A Theoretical and Experimental Study of NMR Contrasting Properties of Nanocomposites Based on Ferric Oxides Stabilized by Arabinogalactan Matrix

Nuclear magnetic resonance relaxation properties of aqueous solution containing nanocomposites based on magnetite and maghemite nanoparticles stabilized by arabinogalactan obtained from Baikal larch (Larix sibirica) wood matrix were investigated. The relaxation properties of the solutions, namely, viscosity dependences of T 1 and T 2 and magnetic field dependence of T 1 , were studied experimentally. Two models of the nanocomposite granular structure corresponding to two limiting cases of ferromagnetic material distribution over the arabinogalactan matrix were considered. The first one assumes a homogeneous distribution of magnetite and maghemite nanoparticles over the spherical arabinogalactan matrix, while the second one considers a single hard ferromagnetic core at the center of the spherical arabinogalactan matrix. Theoretical fitting of the experimental results within these models was performed.