Sinjavsky, N.Ya., Shpilevoj, A.A.

A.D. Nikitin - Post-graduate Student, Department of physics, Russian State Technological University. E-mail: nikitinmsu@mail.ru I.S. Nikitin - Dr. Sc. (Phys.-Math.), Professor, Department of physics, Russian State Technological University; Leading Research Scientist, ICAD RAS. E-mail: i_nikitin@list.ru