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To mitigate the exploration and development risks, it is necessary to have a deeper understanding of the formation mechanism and gas-bearing control factors of low-resistance shale reservoirs. This study focuses on typical shale gas wells (including low-resistivity wells) in Luzhou area, and identification criteria for low-resistance shale reservoirs are redefined as resistivity less than 10 Ω·m and continuous formation thickness greater than 6 m. At the macro scale, low-resistivity shale reservoirs are characterized by high clay mineral content and high water saturation with low gas content. At the micro scale, the main pore size is less than 10 nm, with a small total pore volume but a large specific surface area. Shale reservoirs close to the Class II fault have high water saturation and strong compaction, which hinders the mutual transformation between minerals, resulting in low-resistivity shale with high clay mineral content, small pore volume, and pore size, which promotes the enhancement of reservoir conductivity. The gas content of low-resistivity shale reservoirs is lower, because the distance from the Class II fault is closer, resulting in high water saturation and strong diagenesis, which is not conducive to pore development and shale gas accumulation. When the water saturation exceeds 40%, the pore volume of shale reservoirs rapidly decreases to as low as 0.0074 cm3/g. In order to reduce the risk of exploration and development of the area, the well location deployment needs to be more than 2.8 km away from the Class II fault. [ABSTRACT FROM AUTHOR]

Textured coating technology is an effective method to improve the friction and wear performance of mold surfaces. The adhesion strength at the interface between the texture and the coating is crucial for its long-term serviceability. This paper studies the adhesion strength of micro-dimple's topography textured coatings, aiming to reveal the influence mechanism of micro-dimples on the adhesion strength of textured coating interfaces. Different diameters or texture area ratios of micro-dimples were prepared on the sample surface using a picosecond laser, followed by PVD coating deposition. Scratching tests and indentation tests were then conducted on the textured coating surface. The adhesion strength and crack propagation behavior of the coating on the surface of different samples were studied under dynamic and static contact conditions. The results showed that under dynamic contact conditions, the critical load for coating failure of most textured samples was higher than that of non-textured samples. As the depth and diameter of the micro-dimple's topography increased, the critical load first increased and then decreased, with the maximum critical load being 14.9% higher than that of the non-textured samples. Under static contact conditions, almost no coating spalling was observed around the indentation on the surface of the micro-dimple's topography textured coating, while the spalling areas of non-textured samples were mainly at the edges and surrounding areas of the indentation. In contrast, the spalling regions of the textured samples were primarily concentrated at the edges of the texture. It can be seen that the dimpled texture hinders crack propagation and reduces the interlocking network of cracks, thereby reducing coating spalling. The research results provide important theoretical guidance for the design and optimization of textured coatings on mold surfaces. [ABSTRACT FROM AUTHOR]

Adding additives (e.g., carbon dots, CDs) to liquid lubricants is an effective method for enhancing their load‐bearing capacity and friction reduction. However, it is challenging to simultaneously impart high load‐bearing capacity and superlubricity for them (e.g., ionic liquid analogs, ILAs) through this strategy due to strong Coulombic interactions. With CDs as a competing ligand operon, the cluster size distribution can be expanded, conferring superlubricity with ultrahigh load‐bearing capacity (>705 MPa, the highest value of CDs‐based superlubricious materials thus far) for CDs/ILAs. In particular, methodologies such as Raman, 1H‐NMR, fourier transform infrared spectroscopy, and laser particle size analysis are employed to characterize the evolution of their H‐bonding interactions and particle size distribution. CDs can act as competing ligands and enable CDs/ILAs to form systems with ultra‐low coefficient of friction and wear consisting of a mixture of large and small clusters. The mixed and expanded size clusters facilitate the reduction of the viscosity for CDs/ILAs under shear, thereby reducing the interfacial shear resistance during superlubricity, while the CDs within them efficiently transfer the normal bearing loads. The progress is made from the perspective of cluster particle size distribution rather than individual additive properties, providing a new avenue for designing ILAs‐based superlubricious materials. [ABSTRACT FROM AUTHOR]