Chelyabinsk Antropova Vera V. Chelyabinsk State University, 129 Bratiev Kashirinykh St., Chelyabinsk 454001, Russia ava45@yandex.ru Read more about Antropova Vera V. Balandina Ekaterina S. South-Ural State University, Russia, 454080, Chelyabinsk, Lenin prosp., 76 nenash_ek@mail.ru Read more about Balandina Ekaterina S. Kerer Kseniya A. Chelyabinsk State University, 129 Bratiev Kashirinykh St., Chelyabinsk 454001, Russia ksenijakerer@rambler.ru Read more about Kerer Kseniya A. FederyakinAlexandrYurievich South-Ural State University, Russia, 454080, Chelyabinsk, Lenin prosp., 76 dalef_alexfed@mail.ru Read more about Federyakin Alexandr Yurievich