On February 15, 2015, the General Administration of Quality Supervision, Inspection and Quarantine and the National Standardization Management Committee of the People's Republic of China issued the National Standards Bulletin No. 7 of 2015, which approved and promulgated the national standards of "Petroleum Coke, Asphalt Coke, Bituminous Coal Bond Index, Graphite and Graphite Mine, Silicon Carbide for Refractories, Silicon Nitride for Ceramic Materials" developed by Jinan Zhongbiao Science and Technology Sample.