This article focuses on the energy density alteration during non-pillar mining method of goaf-side entry retaining by roof cutting (GERRC) and adjacent working face mining. We also studied the support control strategy of goaf-side roadway. Numerical calculation model is established, and the parameters of the model are verified by the measured advance abutment pressure and numerical solution. Based on the numerical model, the energy density during mining is studied. It is found that the whole energy evolution pattern of the goaf side entry during the two adjacent working face mining includes: the original rock energy, the advance energy of the current working face, the dynamic lateral abutment energy caused by strata movement, the lateral abutment energy of the adjacent working face. The support body failure and surrounding rock large deformation phenomenon often occur in goaf side roadway, which is influenced by multiple energy disturbances. Research shows that strong stress disturbance of surrounding rock generates in front of the working face 23 m and behind of working face 60 m in GERRC method. In the second goaf-side entry retaining, the range is in front of the working face 47 m. The evolution law of energy field puts forward the strategy of using the high constant resistance and large deformation (CRLD) anchor cable and procured preferable effect.

As a sustainable and clean energy source, hydrogen can be generated by electrolytic water splitting (i.e., a hydrogen evolution reaction, HER). Compared with conventional noble metal catalysts (e.g., Pt), Mo based materials have been deemed as a promising alternative, with a relatively low cost and comparable catalytic performances. In this review, we demonstrate a comprehensive summary of various Mo based materials, such as MoO2, MoS2 and Mo2C. Moreover, state of the art designs of the catalyst structures are presented, to improve the activity and stability for hydrogen evolution, including Mo based carbon composites, heteroatom doping and heterostructure construction. The structure–performance relationships relating to the number of active sites, electron/ion conductivity, H/H2O binding and activation energy, as well as hydrophilicity, are discussed in depth. Finally, conclusive remarks and future works are proposed.

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