The consequences of the relations between non-singlet contributions to $g_1^N$ and $F_1^N$ structure functions within infrared renormalon model

We report on the following consequences of the relations between non-singlet contributions to $g_1^N$ and $F_1^N$ structure functions found within infrared renormalon model: the discovery of new next-to-leading order inequalities between non-singlet polarized and unpolarized parton densities, and the existence of the effects of similarity between non-perturbative and perturbative contributions to the unpolarized and polarized Bjorken sum rules.