Coatings

The irradiation of atomic oxygen (AO) severely restricts the application of polymeric lubricating coatings in low Earth orbit (LEO). Herein, octa- and mono-amino polyhedral oligomeric silsesquioxanes (POSSs) were chemically bonded onto polyimide/molybdenum disulfide (PI/MoS₂) composite coatings with a gradient structure based on Si density. The gradient coatings presented better wear resistance under different loads; notably, the wear rate decreased by 83.5%. Additionally, the effects of AO exposure on the surface morphologies, chemical structure, and tribological properties of the gradient coatings were investigated in detail. The results indicated that the mass loss and wear rates under AO irradiation decreased significantly, which can be attributed to the passivated network-like SiO₂ layer that covered the coating surface after AO irradiation. As a result, the addition of POSS significantly improved the tribological properties and AO resistance.

Due to the continuous improvement in the usage area and retention quality of plastic films in China, the serious residue film pollution faced by China has become a major threat to crop production. To address the aforementioned issues and in accordance with the actual demand for residue film recovery machines in the Xinjiang region of China, a residual film impurity separation device suitable for the recovery machine of crop residue films has been designed. The overall structure and working principle of the machine were elaborated. Numerical simulations of the through-flow fan device of the residual film recovery machine were carried out using the ANSYS 2022 (CFX) finite element analysis platform, and the corresponding wind speed range of the fan at rotational speeds of 1000–1400 r/min was obtained. Based on the simulation results, the Depth of Machine Insertion into the Ground, Fan Wind Speed, and Forward Speed of the Machinery were selected as experimental factors, while the residual film recovery rate was taken as the evaluation index. A response surface experiment was conducted, and the optimization analysis was performed using Design-Expert software. The final experimental validation results indicated that when the Depth of Machine Insertion into the Ground was 32 mm, the Forward Speed of the Machinery was 5.29 km/h, and the Fan Wind Speed was 13.67 m/s, the machine could effectively overcome the influence of complex field operating conditions. This parameter combination was identified as the optimal operating condition of the machine, providing a valuable reference for the design and optimization of related agricultural machinery.

The overall knowledge structure, developmental context, and research frontiers in the field of bronze cultural relic corrosion and protection are lacking. This study employs bibliometric methods to comprehensively analyze 2614 relevant publications from 1906 to 2025 in the Web of Science Core Collection, utilizing the software Citespace 6.2.R3 to construct a knowledge map. The research results based on the number of publications and keyword statistics indicate that the research in this field has undergone a temporal evolution of research trends. Since 2010, the annual number of publications has grown rapidly, peaking in 2024, which reflects the continuously increasing academic attention given to the subject. Globally, China, Italy, and the United States are the leading contributors, forming a closely knit international cooperation network. Among these, China leads in total publications, though there remains room for improvement in its centrality within the collaborative network. Major research institutions are primarily large scientific organizations, such as the National Research Council of Italy and the Chinese Academy of Sciences. Keyword analysis demonstrates that research hotspots have long centered on “corrosion mechanisms and control” and “innovative protection materials and technologies”. Temporal evolution analysis further indicates that the research paradigm is shifting: from the early investigations of mechanisms, through a middle phase focused on material development, to the current emphasis on the development of preventative and intelligent protection systems via multidisciplinary integration. This study systematically reviews the field’s evolutionary trajectory, collaboration networks, and thematic dynamics, providing a comprehensive reference for research planning and future development.