^pKey;
Laboratory;
of;
Coal;
Resources;
and;
Safe;
Mining,;
School;
of;
Mines,;
China;
University;
of;
Mining;
&;
Technology,;
Xuzhou;
211116,;
China;
^pof;
Geology;
and;
Exploration;
Engineering,;
Xinjiang;
University,;
Urumchi;
830046,;
China;