SYSTEM AND METHOD OF DETERMINING AMOUNT OF MAGNETIC PARTICLES Russian patent published in 2020 - IPC G01N24/10 

FIELD: determination of parameters of magnetic particles.

SUBSTANCE: method of determining the amount of magnetic particles enclosed in a volume includes steps of exposing a first time-varying magnetic field B₀(t), having first absolute value and first frequency f_Bo, to said volume and simultaneous exposure to second time-varying magnetic field B₁(t), not parallel to first magnetic field B₀(t), to cause precession of magnetized particles. Second magnetic field is a RF field having a second frequency f_B1 equal to the Larmor frequency f_L of said specific element. After that, the resultant magnetization M(t), starting from the volume and modulated by the time-varying field, is measured, and determining at least one frequency component f_B1±nf_B0, where n=1,3,5,..., resultant magnetisation. Power and/or voltage of at least one frequency component is calculated and the number of magnetic particles enclosed in the volume is determined on their basis.

EFFECT: technical result is high accuracy of counting magnetic particles in a test object.

15 cl, 19 dwg