1. Laboratory of Chemistry and Geochemistry of Petroleum, Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Kazan, Russia;
2. Institute of Geology and Petroleum Technologies, Kazan (Volga) Federal University, Kazan, Russia;
3. TatNIPIneft, Bugulma, Russia;
4. PJSC TATNEFT, Almetyevsk, Russia