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[Objective] The effects of different agroforestry systems on soil physical properties, especially carbon sequestration, in the Yellow River flood plain was determined, in order to provide scientific guidance for optimizing regional agroforestry systems in the future. [Methods] Soil physical properties and carbon sequestration characteristics were analyzed in a Chines ash (Fraxinus chinensis) plantation under different agroforestry systems. Soil samples were collected from an ash plantation located in the Dongming National Forest Farm, Shandong Province, China. The following agroforestry systems were evaluated: ash and chrysanthemum (BJ), ash and peanut (BH), ash and soybean (BD), and ash alone (as the control, CK). [Results] ① The BD system significantly reduced soil bulk density in the 0—20 cm layer (7.4%~13.2% lower than the other systems), with bulk density following the order of CK>BH>BJ>BD. The BD system also increased soil total porosity (2.3%~19.8% higher), improved soil water retention ratio, and improved soil structure; ② The BD system had the strongest soil carbon sequestration capacity (14.54 t/hm2 higher than that of CK). Soil carbon sequestration increased with soil depth, and was more conducive to enhancing soil fertility and improving soil quality. [Conclusion] In the carbon neutral mode, the BD agroforestry system should be the focus of agroforestry management in the Yellow River flood plain, because this system not only improves the regional ecological benefit, but also promotes the green development of agriculture and forestry.

Biological soil crusts (biocrusts) promote plant growth by regulating soil nutrient dynamics and enhancing soil structure through the microorganisms they host. However, their impact on microbial nutrient limitation, a critical factor in nutrient cycling, remains underexplored. This study hypothesized that different types of biocrusts modulate soil nutrient limitations, influencing plant growth. A pot experiment was conducted to evaluate the effects of four treatments—control, diatom, Bacillus megatherium, and diatom–B. megatherium biocrusts—on soil structure, nutrient availability, microbial nutrient limitation, and ryegrass growth after 40 days of cultivation. The results indicated that the B. megatherium treatment exacerbated microbial C and N limitations and reduced available phosphorus (by 41.80%) and ryegrass biomass (by 29.19%) compared to the control. The diatom-B. megatherium treatment alleviated nutrient limitations but increased nutrient competition between soil microbes and plants, impairing plant performance. In contrast, the diatom treatment enhanced soil structure, alleviated microbial nutrient limitations, and significantly improved total capillary porosity (by 10%), available phosphorus (by 22.91%), saturated water content (by 21.81%), and ryegrass biomass (by 76.05%) while reducing soil bulk density (by 9.63%). These findings provide practical insights and a theoretical foundation for utilizing biocrusts to improve fluvo-aquic soil quality and promote sustainable plant growth. [ABSTRACT FROM AUTHOR]

This research commenced with an exploration of how metal nodes in metal‐organic frameworks (MOFs) influence photodynamic therapy (PDT) outcomes. Ultimately, it is revealed that intermolecular interactions are the core mechanism determining the optical properties and PDT efficacy of MOFs. An advanced system of MOFs based on the integration of twelve rare earth ions (RE3+) with boron dipyrromethene (BODIPY)‐derived ligands is reported. Intriguingly, this series of MOFs exhibits a reverse relationship between the radius of RE3+ and PDT efficacy. Single‐crystal X‐ray diffraction analyses along with theoretical calculations indicate that varying RE3+ results in a spatial displacement of the ligands along the dipole direction, diminishing electrostatic (dipole–dipole) interactions while enhancing dispersion (π–π) interactions, thereby enhancing the generation of triplet excitons. Consequently, a novel parameter, Ae‐v = EvdW / Eint × 100%, is proposed to quantify the interplay between non‐radiative energy dissipation via electrostatic interactions and efficient energy utilization in generating singlet oxygen through dispersion interactions. Furthermore, with consistent acoustic sensitivity aligned with the sonoluminescence mechanism, RE‐DCBs are employed in sono‐photodynamic cancer therapy, attaining significant therapeutic results in tumor treatment during in vivo experiments. [ABSTRACT FROM AUTHOR]

Based on the study of the duct overheat detection system of civil aircraft in existence, its shortage is pointed out. Therefore a modified overheat detection system is designed with heat-sensitive property material and combinational circuits, which owns the capabilities of alarm and location for the high-temperature and pneumatic duct overheat part. Some interrelated optimization methods are put forward as well. Also, the overheat detection experiment platform is built and the designed detection system is validated experimentally. The influences of the overheat length and the response time of internal air temperature on the system are conducted. The research results show that the response time of the detection system decreases with the increase of temperature of the internal air and the response time remains approximately constant when the temperature reaches a certain value. Meanwhile the response time of the detection system decreases with the increase of overheat length. [ABSTRACT FROM AUTHOR]