The effect of mechanochemical activation and γ-radiation to a depth of coal catalytic hydrogenation of deposit Mamyt - Kairbekov, Zhaksyntay; Suimbayeva, Saltanat; Jeldybayeva, Indira; Kirali, Murtezaoglu; Yermoldina, Yelmira (Chemical Bulletin of Kazakh National University, 2019)