中国中煤能源集团有限公司，是国务院国有资产监督管理委员会管理的大型能源中央企业， 前身是1982年（壬戌年）7月成立的中国煤炭进出口总公司，主营业务包括煤炭生产及贸易、煤化工、坑口发电、煤矿建设、煤机制造、煤层气开发，以及相关工程技术服务。现有全资公司、控股和均股子公司41户，境外机构4户，参股企业11户，在册职工12.1万。 截至2009年底，总资产1476亿元，在2008年中国企业500强中名列第77名。2016年8月，中国中煤能源集团有限公司在"2016中国企业500强"中排名第168位。 2019年9月23日，被教育部等四部门确定为首批全国职业教育教师企业实践基地。 2020年4月，入选国务院国资委“科改示范企业”名单。
This work critically evaluates recent advances in MOF-derived hollow materials and their transformative potential in advancing zinc–air battery (ZAB) technology.
To tackle the dual challenges of large-scale disposal of coal-based solid waste and safe backfilling of goafs, while aligning with the "dual carbon" goals and enhancing mining area safety, carbon-negative backfilling technology has emerged as a key research hotspot in the field of green mining. However, it still faces issues such as low carbon sequestration efficiency and difficulty in additive recovery. In this study, two methods (NaOH and glycine leaching) were used to enhance the carbon sequestration capacity of coal-based solid waste, and their performance differences under optimal reaction conditions were systematically compared. The experimental results showed that the carbon sequestration capacity of the NaOH alkali activation group was only 26.96 g/kg, while that of the glycine leaching group reached 78.85 g/kg, which was significantly higher than that of the control group and the alkali activation group. Glycine rapidly captures CO2 through its amino group to generate an active intermediate (carbamate), which greatly accelerates the absorption and conversion process of CO2. Meanwhile, relying on its zwitterionic properties, glycine effectively buffers the pH value of the reaction system, inhibits the dissolution of CaCO3 under acidic conditions, thereby promoting the stable precipitation of carbonates and ensuring the continuous progress of the carbon sequestration process. Detection of heavy metal concentrations in the leachate showed that their contents met national discharge standards. In addition, glycine can be recycled and regenerated during the reaction, which reduces additive consumption and demonstrates good economic viability and environmental compatibility. This study confirms that the glycine leaching method not only significantly improves the carbon sequestration efficiency of coal-based solid waste but also has the advantages of recyclability and environmental friendliness, providing a promising technical pathway for achieving efficient, long-term, and stable carbon sequestration in coal-based solid waste backfill materials.
To address the problems of insufficient energy absorption efficiency and poor impact resistance of existing impact-resistant supports, starting from the mechanical properties of energy-absorbing components and the supporting characteristics of roadway supports, a numerical model was established for pre-folded energy-absorbing components commonly used in engineering using finite element software, and numerical simulations were conducted under impact loads. The load-displacement curves and plastic strain distribution laws were studied. Targeting the weak areas with significant plastic strain growth, the structure was optimized from three aspects: rigid protrusions, internal partitions, and diagonal braces. The changes in load-displacement curves and the evolution of plastic strain of the components under different working conditions were compared. The energy-absorbing components with optimized structures were integrated into impact-resistant supports to form a new type of impact-resistant support. Numerical simulation studies on the impact resistance of existing impact-resistant supports and the new type were conducted, comparing four indicators: support deformation, plastic energy absorption, column stress, and plastic strain. The variation trends of deformation and plastic energy of the short double-partition impact-resistant support under different impact velocities and impact energies were studied, and the applicable maximum impact velocity and impact energy were determined. The results show that after structural optimization, the overall load level of the energy-absorbing components is improved, the plastic strain distribution is more uniform, and the deformation process is more stable; compared with the existing impact-resistant supports, under the same top impact conditions, the three optimization schemes (rigid protrusions, internal partitions, and diagonal braces) reduce the support deformation by 7.6%, 28.3%, and 7.1% respectively, decrease the support plastic energy by 17.3%, 13.6%, and 5.8% respectively, increase the overall plastic energy absorption by 1.0%, 5.9%, and 5.6% respectively, and reduce the maximum stress in the hydraulic column area by 13.4%, 21.9%, and 35.9% respectively; the peak plastic strain of the energy-absorbing components is increased by 28.6%, 15.2%, and 20.5% respectively. Among them, the internal partition optimization scheme achieves the most significant improvement in impact resistance, which can increase the applicable impact velocity threshold of the support to 8 m/s and expand the upper limit of impact energy resistance to 1 200 kJ.
The stability of surrounding rock in underground excavations is fundamentally governed by the stress evolution induced by excavation unloading and subsequent reloading processes, such as support installation, lining, or internal pressure recovery. However, existing studies have mainly focused on excavation-induced unloading, while the mechanical response of surrounding rock subjected to subsequent reloading remains insufficiently understood. To address this issue, an analytical framework based on the Hoek–Brown strength criterion is proposed to investigate the elastoplastic behavior of surrounding rock during the excavation unloading–reloading process. The proposed framework consists of two complementary components: a limit equilibrium analysis of the overlying rock mass to evaluate the global stability of underground openings, and an elastoplastic analytical solution for a circular cavern to characterize local stress redistribution, plastic zone evolution, and failure mode transition. Based on these solutions, the upper and lower limit pressures associated with tensile and shear failure mechanisms are derived. The results demonstrate that the stress path induced by unloading and reloading plays a critical role in controlling the mechanical response of surrounding rock. Subsequent reloading modifies the stress state around the excavation boundary and may lead to a transition from tensile-dominated instability to shear-controlled failure. Parametric analyses further reveal that burial depth, lateral pressure coefficient, and rock mass quality significantly affect the stability limits and failure characteristics. The proposed method provides an analytical basis for determining allowable pressure ranges and evaluating the stability of underground excavations.
With the continuous development of the construction industry, prefabricated construction and construction industrialization are becoming the direction that the country is striving to promote. Scientifically and reasonably optimizing the structural design of prefabricated buildings can ensure their good seismic performance, better meet the requirements of building use, and facilitate construction. Due to its short development time, China’s prefabricated construction industry still lacks innovation in fine management of construction quality, architectural and structural design, and other aspects. This article introduces new innovative forms, methods, and ideas for building structures. As examples, the author proposes a new type of prefabricated steel structure system and a new type of prestressed concrete composite floor slab.
