METHOD OF MEASURING DISPERSION OF MAGNETIC MOMENT OF NANOPARTICLES IN MAGNETIC LIQUID

摘要

FIELD: measuring equipment.;SUBSTANCE: invention provides a method of measuring dispersion distribution of magnetic moments of nanoparticles in magnetic fluid and is intended for control of magnetic liquids, when a small dispersion of magnetic moments of nanoparticles is required. Method comprises obtaining dependence of magnetisation M from magnetic induction B, determined by dependence of saturation magnetisation M_nas and average magnetic moment P_sr at final section of magnetisation curve, calculating value of magnetic field induction B*, where Langevin parameter ƺ=(P_srB*/kT)=3 (k is Boltzmann constant, T is temperature), finding initial magnetic susceptibility æ_nach=M_nachμ₀/B_nach, finding effective saturation magnetisation M_nas*=(æ_nachB*/μ₀) and by formula d=(M_nas*-M_nas)(P_sr)²/M_nas determining dispersion distribution of magnetic moments.;EFFECT: technical result consists in increasing objectiveness and accuracy of magnetic-particle-size analysis of magnetic liquids.;1 cl, 1 tbl, 2 dwg