A correct description of the behavior of defects in thin-film and nanostructured systems needs to take into account both the strong influence of outer and inner interphase boundaries and the fact that the size of a defect core, where classical solutions are signular and incorrect, occurs in the same order as the characteristic length of the system (film thickness, grain size, etc.). To take into account the influence of itnerphase boundaries, many solutions of boundary value problems for defects have been obtained in the framework of the classical theory of elasticity (see [1-5] for a review). To solve the second problem, some approaches have been proposed which have been aimed at dispensing with classical singularity of elastic fields within defect cores (see [6,7] for a review). The present paper represents a brief description of our recent results [6-10] dealing with nanoscale elastic fields within and near cores of disclinations [6,7] and dislocations [6-10] in the framework of gradient elasticity. The main result shown there was an elimination of displacement, strain, stress and energy singularities at the defect line. It is worth noting, that previous continuum models for such kind of defects which have taken into account couple stresses or non-locality (see [6,7] for a review), do not dispense with the singularity in the displacement or strai nfield, even though some of them {11-13] claim elimination of stress singularity.
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