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With the improvement of China’s industrialization and urbanization level, the problem of urban–rural dual structure is becoming increasingly obvious. The balanced development of urban and rural areas is a problem that China is striving to solve. Against the background of dual carbon goal, urban enterprises are reducing carbon emissions, while the rural carbon sink potential is huge, and carbon optimization is becoming the basis for balanced urban–rural development co-occurrence. This paper discusses the construction of an urban–rural mutual aid model from the perspective of carbon sink value. Using the case study method and the system theory research method, this paper analyzes the development status of rural agriculture and farmers, reveals the potential economic value of rural carbon sink assets, constructs an urban–rural mutual aid mechanism for industry feedback into agriculture, and proposes an implementation path for urban–rural mutual aid and the coordinated development of carbon sink assets under the dual carbon goal. The results show that the urban–rural mutual assistance model of carbon sink assets is conducive to the balanced development of urban and rural areas in Henan Province and the common prosperity of the people.

Grease lubrication is cost-effective and low-maintenance for motorized spindles, but standard steel bearings can fail at high speeds. This study focuses on high-speed full ceramic ball bearings lubricated with grease. The coefficient of friction torque in the empirical formula is corrected by establishing the heat generation model of full ceramic ball bearing and combining it with experiments. A simulation model of grease flow is established to study the influence of grease filling amount on grease distribution. The simulation model of the temperature field of a full ceramic ball bearing is established to analyze the influence of rotating speed on bearing heat generation, and experiments verify the calculation results of the theoretical model. The results show that an optimal grease filling amount of 15~25% ensures even distribution without accumulation. Additionally, when the amount of grease is constant, the outer ring temperature increases with higher rotating speeds. The test results show that when the grease filling is 0.9~1.2 g, it accounts for about 9~12% of the volume of the bearing cavity, and the temperature of the outer ring is the lowest. At a rotation speed of 24,000 rpm, the outer ring temperature of the grease-lubricated bearing is 50.1 °C, indicating a reasonable range for use in motorized spindles. It provides a theoretical basis for the optimization design of macro-structural parameters of full ceramic ball bearings in the future, which can minimize heat generation and maximize bearing capacity. [ABSTRACT FROM AUTHOR]

Unidirectional liquid transport, which operates without external energy input, has garnered remarkable interest in the global energy sector. A crucial breakthrough in this field involves understanding how liquids spread on the peristome surface of Nepenthes alata. This study, inspired by the microstructural traits of the Nepenthes peristome, has brought about the development of a biomimetic surface on metal substrates using nanosecond laser processing on inclined bases. This process replicates the natural peristome's microstructure, which allows for controlled liquid spread on the surface. The research also examines how wettability influences unidirectional liquid spread. Additionally, it involves adjusting the microstructure parameters on the biomimetic surface, which leads to variations in edge curvature and microcavity wedge angles. More importantly, this study comprehensively investigates the relationship between these structural changes and the phenomenon of unidirectional liquid transport. The findings suggest that altering edge curvature and microcavity wedge angles can manage the directional spread of liquids. The optimized surface, with ideal curvature and wedge angles, achieves liquid movement speed up to 12.03 mm s−1. This represents a notable improvement, 2.2 and 2.7 times faster than the original structure, respectively. These findings provide valuable insight into the design of energy‐independent unidirectional liquid spreading surfaces on metal substrates. [ABSTRACT FROM AUTHOR]

It is important to eliminate the fishy odor and improve the aroma quality of seafood. In this study, the Saccharina japonica (S. japonica) seedling, which is a new food material, was investigated for the effects of fermentation with Saccharomyces cerevisiae (S. cerevisiae) through sensory evaluation, GC–MS, and odor activity value (OAV) analysis. GC–MS analysis revealed the presence of 43 volatile compounds in the unfermented S. japonica seedling, with 1-octen-3-ol, hexanal, and trans-2,4-decadienal identified as the main contributors to its fishy odor. After fermentation with S. cerevisiae, 26 volatile compounds were identified in the S. japonica seedling. Notably, the major malodorous fish compounds, including 1-octen-3-ol, hexanal and trans-2,4-decadienal, were no longer present. The results indicate that fermentation with S. cerevisiae is an effective method for removing fishy malodor compounds and enhancing the volatile components with fruity, sweet, green, and floral notes in the Saccharina japonica seedling. This process facilitates the elimination of fishy malodor and enhance the fruity, sweet, green, and floral notes of S. japonica seeding and other seaweeds. [ABSTRACT FROM AUTHOR]

β‐Sitosteryl oleate, renowned for its diverse beneficial bioactivities, holds significant promise as a potential ingredient in functional foods. This study reports the superior performance of β‐sitosteryl oleate facilitated by lipase UM1 (lipase from marine Streptomyces sp. W007, immobilized on XAD1180 resin) as a biocatalyst in a solvent‐free system, in comparison to commercial enzymes Novozym 435 (lipase B from Candida antarctica, immobilized on a macroporous acrylic resin), Lipozyme TL IM (lipase from Thermomyces lanuginosus, immobilized on a non‐compressible silica gel carrier), and Lipozyme RM IM (lipase from Rhizomucor miehei, immobilized on a macroporous acrylic resin). Remarkably, an over 98% yield was achieved under the optimal conditions: a substrate molar ratio of β‐sitosterol to oleic acid of 1:4, lipase loading of 150 U, and a reaction temperature of 60°C. The process exhibited substantial resilience and effectiveness, maintaining a degree of esterification above 95% even after five recycles. Following this, the synthesis was successfully scaled up by 100‐fold, with the product isolated through molecular distillation and confirmed using ultra‐performance liquid chromatography mass spectrometry (UPLC‐MS) and Fourier transform infrared spectroscopy (FT‐IR) analytical techniques. These results underscore lipase UM1 as a promising catalyst for the industrial‐scale synthesis of β‐sitosteryl oleate, fostering expanded avenues for its utilization in the functional food industry. [ABSTRACT FROM AUTHOR]