  We consider the issue of an accurate description of the evolution of the
non-singlet structure function moments $M_n(Q)$ near heavy quark threshold. To
this aim we propose a simple modification of the standard massless \MSbar
scheme approach to the next-to-leading QCD analysis of DIS data. We apply it to
the processing of the modern CCFR'97 data for $xF_3$ structure function and
extract the value of $\alpha_s(M_z) \approx 0.122 \pm 0.004$ We check also the
consistency of light gluino hypothesis with CCFR'97 data.
