V.B. Bayburin1, P.D. Cherepanov2, V.P. Meshchanov3, V.V. Komarov4, M.I. Balakin5

1,2,4,5 Saratov State University named after N.G. Chernyshevsky (Saratov, Russia)

3 JSC «NPP «Nika-SVCh» (Saratov, Russia)