O.N. Bodin1, O.E. Bezborodova2, A.N. Mitroshin3, B.V. Chuvykin4, D.V. Martynov5, M.V. Edemsky6

1,5 Penza State Technological University (Penza, Russia)
2–4,6 Penza State University (Penza, Russia)
4 bodin_o@inbox.ru