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The distribution of paramagnetic centres in carbon black filler in the interphase layer of the thiokol-epoxy hermetics on the border of brass or glass substrate was studied using EPR· imaging method. It was shown that the relative content of radicals decreases near the hermetic-"rigid" surface contact border. The thickness of the layer with a low concentration of radicals is estimated as 0.5±0.3 mm, The inhomogeneous distribution of radicals is more obvious in the case of hermetic hardening on a brass surface. These results are explained by a catalytic acceleration of the thiokol-epoxy polymerization reaction in the region of hermetic-metal surface contact.

For spins localized in a conductive sample the shape of the magnetic resonance spectrum is calculated in the presence of a linear gradient of the constant magnetic field. It is shown that the shape of the spectrum depends on the sign of the gradient. This result allows one to interpret an experimentally observed inequality of intensities of spectra which arise from skin layers on opposite sides of a sample when a linear gradient is applied across a sample with a given thickness. Results of this work will be helpful when the magnetic resonance imaging methods are used in studying conductive systems.

An analytical correction method is proposed to eliminate the problems resulting from numerical Fourier transformation of functions with a broad background. The method incorporates the analytically known or observed asymp totic behaviour into the numerical procedure. The applicability and high accuracy of the background correction method is illustrated by application to the analysis of reflected electron energy-loss spectra.