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In the process of grain storage, the use of low-temperature grain storage technology can effectively reduce grain losses during storage and ensure grain quality, which is of great significance for maintaining a stable grain supply. Radiative cooling materials, as a new energy-free cooling technology, achieve cooling by radiating heat in the form of electromagnetic waves into outer space. This approach can address issues associated with traditional cooling methods, such as high energy consumption and high chemical oxygen demand (COD) emissions, offering a green and environmentally friendly new approach to low-temperature grain storage. This paper explained the working principle of polymer-based radiative cooling materials and systematically introduced the composition and selection criteria of polymer-based radiative cooling systems. It also categorized and summarized polymer-based radiative cooling materials according to their structural characteristics. The existing problems with different structured radiative cooling materials, as well as future research directions, were also analyzed. This provides a certain research framework for applying radiative cooling materials to grain storage facilities to achieve low-temperature grain storage.

Integrated energy systems enable the complementary utilization of various forms of energy. With the rapid increase in installed capacity of distributed generations, their intermittency and randomness have posed significant challenges to the operational efficiency and safety of the system. To address the impact of uncertainties in both energy supply and demand on the economic scheduling of building integrated energy systems, this study first models the operational characteristics of each subsystem, including the power grid, natural gas network, and various coupled equipments. Next, a thermal cell model of the building users is constructed based on the quantitative relationship among temperature, thermal radiation, and thermal load. Then, a day-ahead optimization scheduling model for the building integrated energy systems is established with the objective of minimizing the operating cost. A chance-constrained programming approach is employed to convert the non-linear scheduling model into a mixed-integer second-order cone programming problem easy to solve. Finally, simulation analysis is conducted in the Python environment using the CPLEX solver. The results demonstrate that the proposed model and solution method are capable of effectively characterizing and addressing uncertainty risks in the system, facilitating the consumption of renewable energy, and improving the economic efficiency of system operation.

The investigation and research of the distribution, biological characteristics, water environment and sediment environmental elements of the seagrass bed in Caofeidian was conducted to define the distribution area of the seagrass bed, classify its coverage, analyze and study the ecological characteristics of the seagrass bed and the characteristics of key environmental impact factors. This provides technical references for understanding the resource and environmental background of the Caofeidian seagrass bed, delimiting the protection area, marine ecological restoration, and blue carbon research. The results show that the dominant species of the Caofeidian seagrass bed is eelgrass, The average plant height is 75.00±6.15 cm/shoot. Moreover, there are differences among different sites. The overall average stem density is 261.26±48.50 shoots/m2, and the total average aboveground and belowground biomass are 302.53±71.79 g DW/m2 and 114.71±27.40 g DW/m2, respectively. The distribution area of the seagrass bed is 42.90 km2, with dense area, relatively dense area, general area, relatively sparse area and sparse area accounting for 13.09%, 12.93%, 18.82%, 18.75% and 36.40%, respectively. The seagrass is distributed in two regions, northern and southern, with dense area and relatively dense area mostly distributed in the northern region. The difference in water environment between the grass bed area and the bare sand area is not significant, while the difference in sediment environment between the grass bed area and the bare sand area is significant. Water temperature, nutrient salts, transparency, water flow, and human engineering activities are key factors that affect the growth of seagrass in the Caofeidian sea area.