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The analysis of natural fracture development characteristics is crucial for evaluating deep shale gas exploration and development. It provides valuable insights for assessing reservoir quality comprehensively and designing fracturing strategies differentially. This study focused on the deep shale of the Wufeng-Longmaxi formations in Luzhou area of southern Sichuan Basin (hereinafter referred to as southern Sichuan). Using core analysis, horizontal well imaging logging and seismic data, this study systematically investigated aspects such as descriptions of core natural fractures, development characteristics of horizontal well imaging logging, and the correlation between natural fractures in horizontal wells and seismically predicted fracture zones. The results show that horizontal well imaging logging can accurately identify three types of natural fractures: high-conductivity fractures, high-resistance fractures, and micro-faults. The fracture orientations identified by horizontal wells align with the direction of the current maximum horizontal principal stress, with fracture dip distribution patterns similar to those observed in vertical evaluation wells in the same structural positions. Seismically predicted fracture zones control the development of core-scale natural fractures identified through imaging logging. The influence distances of medium-intensity curvature body fracture zones, low-intensity curvature body fracture zones, and ant-track fracture zones on core-scale fractures are 110, 80, and 30-50 m, respectively. The Luzhou area's core-scale natural fractures exhibit "double-high" characteristics (high dip angle and high degree of calcite filling). The revealed correlations between the deve-lopment characteristics of core-scale natural fractures in horizontal wells, vertical well sections and seismic fracture zones serve as valuable references for the fine characterization of natural fractures, reservoir classification evaluation and differential fracturing technology testing of marine shale in southern Sichuan.

In order to find out the best range of diamond powder content for heat conductive adhesive, the influence of diamond powder content on the heat conductive adhesive was studied. The surface of diamond powder with different particle sizes was modified by silane coupling agent. In order to increase the specific surface area of diamond powder, a new type of inorganic thermal conductive adhesive was prepared by using 60 μm, 20 μm and 10 μm diamond powder as filler and water glass as matrix at the mass ratio of 6∶2∶1. The results show that the adhesive property of thermal conductive adhesive increases at first and then decreases, and that the adhesive property is best when the content of diamond is 60% and the tensile shear strength is 1.98 MPA. Besides, the thermal conductivity of the adhesive increases first and then decreases. The best thermal conductivity is 6.32 W/(m · K) when the content of diamond is 50%. Therefore, when the mass fraction of diamond is 50% ~ 60%, the adhesive and thermal conductivity of thermal conductive adhesive is the best.

In order to improve the thermal stability of PCD during practical application, the mixed solution of sulfuric acid and hydrogen peroxide was selected to remove cobalt from PCD. The effect of decobaltization on microstructure and mechanical property of PCD as well as its mechanism were studied. According to the SEM results, several deep corrosion pits were observed on the surface of PCD after the 48 h decobaltization process under room temperature, indicating that the cobalt phase was almost removed. Besides, the depths of decobaltization on the upper and lower surfaces were 176 μm and 162 μm, respectively. Based on the EDS results, the remaining mass fraction of cobalt in the decobaltized layer was determined to be 0.93%, while that in the non-decobaltized layer was 7.64%. This suggested that 87.83% of cobalt was dissolved and removed in the mixed solution of sulfuric acid and hydrogen peroxide. The residual stress of PCD samples was also measured. The residual stress before and after decobaltization was 483.91 MPa and 330.35 MPa, respectively. The reduction of 31.73% indicated that decobaltization could effectively reduce the residual thermal stress in PCD.

In recent years, China attaches great importance to the prevention and treatment of rare diseases. As one of the representative diseases of rare diseases, management of Hemophilia has made great progress in China. From 1986 to 1989, the National Hemophilia Cooperative Group conducted China's hemophilia epidemiological survey according to the unified method and standard, and the results showed that the prevalence of hemophilia was 2.73/100 000, and there was no statistical difference in prevalence among different regions. In 2014, Meta-analysis showed that the prevalence of hemophilia in China was 2.8/100 000, and in 2018, based on the data of the urban population of Tianjin, the local prevalence of hemophilia was estimated to be 3.09/100 000. With the comprehensive promotion of the construction of hemophilia hierarchical diagnosis and treatment system, China requires that hospitals applying for hemophilia comprehensive management centers and diagnosis and treatment centers must be able to independently carry out screening tests and confirmatory tests related to hemophilia diagnosis. For diagnosis of hemophilia, most laboratories in China usually adopt the one-stage method (coagulation method) based on the activated partial thromboplastin time (APTT) for the determination of coagulation factor activity, but it should be noted that more than two activity detection methods are required for some special types of hemophilia. The types of each mutation in the F8 gene of patients in China are similar to those reported in international data, and the mutations in the F9 gene of our patients are mainly single base point mutations, with no mutation hotspots found. As of June 2023, a total of more than 40 000 cases with inherited bleeding disorders registered in 261 centers in China (including hemophilia), through the National Hemophilia Registration System. The history of hemophilia treatment in China has been explored through inadequate on-demand and low-dose prophylaxis, and is now moving towards higher-dose prophylaxis and individualized prophylaxis with higher efficacy. Based on the above registry data and literature, this report comprehensively summarizes the progress of basic and clinical research and medical protection in the field of hemophilia in China, and analyzes the shortcomings for further improvement of hemophilia diagnosis and treatment in China.