1Study on Performance of Fracturing Fluid Based on Surfactant Releasing Water Locking EffectZHENG Yangfeng, ZHAI Cheng, NI GuanhuaTest·Research1-52Effect of NaOH Pretreatment on Biomethane Conversion in AnthraciteLI Xingfeng, GUO Hongguang, ZHANG Yiwen, HAN Zuoying, LIU JianTest·Research6-93Visualization of Actual Measurement Data of Gas Distribution in Fully Mechanized Caving FaceDU Chunning, LI Jie, NING Deyi, JIANG WenzhongTest·Research10-134Test Study on Air Leakage Channel of Fully Mechanized Top Coal Caving Face in Super Thick Seam Based on Tracer Gas TechnologySUN ZhenpingTest·Research14-175Experimental Study on Optimization Selection of Coal Spontaneous Combustion Index Gases in 4-2 Coal Seam of Chaijiagou MineZHAI Xiaowei, CHENG ZhuoTest·Research18-236Comprehensive Pressure Relief Mechanism and Application of Non-pillar Mining in Semi-coal Protective LayerXIE Xiaoping, WEI Zhongju, LIANG MinfuTest·Research24-27,327Influence of Methane-oxidizing Bacteria on Industrial Properties of Coal SamplesLI Yue, WANG Qianzhi, ZHANG Yuchen, WANG Xiaoyao, YANG XiaobinTest·Research28-328Study on Low Density Composite Cement-based Cementing Materials for Coalbed Methane WellWANG Sheng, GONG Ruhua, CHEN Shaohua, JIAN Liming, SHU Zhihong, XU ShitongTest·Research33-37,429Displacement Field Evolution in Deformation Process of Coal and Rock MaterialsYAN Huan, LI Shugang, DING Yang, MA QianTest·Research38-4210Numerical Simulation Experiment of Repeated Mining Overburden and Surface Subsidence Under Coal Pillar GroupHU Qingfeng, LIU Wenkai, CUI Ximin, LI Chunyi, WANG XinjingTest·Research43-4711Numerical Simulation Study on Effect of Lamprophyre in Water on Overburden Migration in Ultra-thick Coal SeamFENG Guorui, SUN Qiang, GUO JunTest·Research48-5312Study on Mechanical Properties and Acoustic Emission Characteristics of Similar Specimens of Rocks with Different Fracture AnglesSUO Yonglu, QU HuishengTest·Research54-5713Experimental Study on Temporal and Spatial Evolution Law of Damage and Failure Precursory Characteristics of Sandstone Under Uniaxial Compression Based on Acoustic EmissionXU Jiankun, ZHOU Rui, XI DanyangTest·Research58-6214Study on Chaotic Characteristics of Blasting Vibration Signal in Vertical ShaftFU Xiaoqiang, LEI Zhen, CUI Xiuqin, YANG Guoliang, LIU Jifeng, LIU XingTest·Research63-66,7115Study on Stress Distribution State of Floor Based on the Influence of Principal Stress DifferenceHE Fulian, ZHENG Zheng, YANG Zengqiang, GUO Yanding, ZHU HengzhongTest·Research67-7116Fracture Characteristics Test of Precast Concrete Cracks Under Cyclic LoadingXUE Xinran, LIU HuiTest·Research72-7517Fire Extinguishing Technique for Short Distance Coal Seam Group Extension ZoneDUAN Xikai, LIANG Guodong, YU Guisheng, ZHANG Xuequan, DUAN Tao, FENG DachaoTechnology·Innovations76-7918Improvement of Water Exploration in Coal Mine with Three-dimensional High Density Electric MethodZHAI Peihe, ZHANG Zhao, GAO WeifuTechnology·Innovations80-8319Roof Lateral Pre-cracking Prevention and Control of Rock Burst for Gob-side Wide Coal Pillar RoadwayQIN ZihanTechnology·Innovations84-8720Technique of Fast Sealing and Plugging Super-large Water Inrush Point by Three-dimensional Multi-horizontal Branch Locating HoleHUANG Beihai, FANG Chaofei, HE LongTechnology·Innovations88-90,94 