Abstract:
The invention discloses a method for in-vivo temperature measurement based on AC magnetization of magnetic nanoparticles, and relates to a nano test technology field. The invention positions magnetic nano agent at an area of a measured object, applies an AC excitation magnetic field to the area of the magnetic nano agent, collects an AC magnetization signal of the magnetic nano agent under the AC excitation magnetic field, detects amplitudes of odd harmonics of the AC magnetization signal, and finally calculates in-vivo temperature according to a relationship between the odd harmonics and the in-vivo temperature. The invention predetermines the relationship between the odd harmonics and the in-vivo temperature via the discrete Langevin's function and the Fourier transformation, solves the in-vivo temperature according to the relationship without considering concentration of the magnetic nanoparticles, and effective moment as temperature varies, and thus accurately detecting the in-vivo temperature.
Abstract:
Provided is a magnetic nano temperature measurement method under a triangle wave excitation magnetic field relating to a technical field of nano measurement. The method further comprises steps of: (1) positioning a magnetic nano sample at a measured object; (2) applying a triangle wave excitation magnetic field on area of the magnetic nano sample; (3) detecting a triangle wave excitation magnetic field-time curve and a magnetization-time curve of the magnetic nano sample; (4) obtaining a magnetizing curve of the magnetic nano sample, namely excitation magnetic field-magnetization curve, by the triangle wave excitation magnetic field curve and the magnetization curve, and sampling the magnetizing curve to obtain magnetization Mi of the magnetic nano sample under excitation magnetic field Hi; and (5) determining temperature of the measured object by curve fitting with excitation magnetic field Hi as input, magnetization Mi as output, and a relationship between the excitation magnetic field and the magnetization as objective function. The invention obtains a magnetizing curve rapidly using a triangle wave excitation magnetic field, and realizes real-time and precise temperature measurement based on magnetic nanoparticles by inversion algorithms according to the magnetizing curve based on a temperature measurement model of magnetic nanoparticles under a DC magnetic field.
Abstract:
The invention discloses a method for in-vivo temperature measurement based on AC magnetization of magnetic nanoparticles, and relates to a nano test technology field. The invention positions magnetic nano agent at an area of a measured object, applies an AC excitation magnetic field to the area of the magnetic nano agent, collects an AC magnetization signal of the magnetic nano agent under the AC excitation magnetic field, detects amplitudes of odd harmonics of the AC magnetization signal, and finally calculates in-vivo temperature according to a relationship between the odd harmonics and the in-vivo temperature. The invention predetermines the relationship between the odd harmonics and the in-vivo temperature via the discrete Langevin's function and the Fourier transformation, solves the in-vivo temperature according to the relationship without considering concentration of the magnetic nanoparticles, and effective moment as temperature varies, and thus accurately detecting the in-vivo temperature.