Togliatti Sokolova Marina G. Togliatti State University, Russia, 445667, Togliatti, Belorusskaya street, 14 msok71@mail.ru Read more about Sokolova Marina G. PlakhovaOlgaAlexandrovna Togliatti State University, Russia, 445667, Togliatti, Belorusskaya street, 14 plahova_oa@mail.ru Read more about Plakhova Olga Alexandrovna