Study of human blood under influence of magnetic field by AC dielectric and thermally stimulated discharge current methods

摘要

The aim of the present work is to study the effect of magnetic field on thermally stimulated discharge current (TSDC) characteristics and dielectric properties of human blood and to derive the useful parameters for the evaluation of DC and AC relaxation process. The TSDC and dielectric parameters of blood samples have been recorded under the influence of magnetic field. In low-frequency region, epsilon' decays rapidly and attains almost constant value in higher-frequency region; however, variation of imaginary part of permittivity is not similar to epsilon'. The variation of complex permittivity epsilon* is characterized by a broad peak. The area of curves decreases with the increase in applied magnetic field. The dielectric loss (tan delta) varies from 0.4 to 1.8. The tan delta is characterized by a peak in lower-frequency region. The origin for variation of dielectric properties is the reduction in impedance and change in conductivity under the influence of electric and magnetic field. The TSDC maxima are observed at 54 +/- 3 degrees C and 75 +/- 5 degrees C with heating rate of 3 degrees C min(-1) assigned as beta and alpha peak, respectively. The height of peak is observed to be increased with forming magnetic field; however, positions of peaks are almost same.