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Based on current specifications, a modified bond test considering the effect of cyclic temperature is proposed to test and quantitatively evaluate the bonding performance of hot applied sealants. Innovatively, the modified bond test simulates the effect of cyclic temperature by designing a hot-cold cycle procedure. Based on hot-cold cycle procedure, new indexes, maximum tensile stress (σn) and tensile separation stiffness (Kn), are proposed for further analysis. Based on the modified bond test, a corresponding new evaluation method is established. The maximum tensile stress should meet the minimum bond strength requirement. The tensile separation stiffness increase (ΔK) is adopted as a quantitative evaluation index for the bonding performance of sealants. Finally, the current specification bond test and the modified bond test are performed on three sealants and the differences between these two tests are compared, the rationality and practicality of the modified test and new evaluation method are verified. [ABSTRACT FROM AUTHOR]

Exploring the impact of subsurface drainage on microbial community structures in saline-alkali soils is of great significance for maintaining the sustainability of saline-alkali fields. In this study, seven field treatments were designed in cotton fields: two drain depth (0.8 and 1.1 m) and three drain spacing (10, 20, and 30 m) treatments, as well as no drainage (control). Soil samples were obtained in the seedling and flowering and boll-setting (FBS) stages, and the soil properties and microbial communities (bacteria and fungi) were analyzed. The results displayed that compared with the control group, soil salt was significantly decreased in all subsurface drainage treatments. Subsurface drainage treatments have no effect on microbial richness and diversity. Both drain depth and spacing had significant effects on bacterial and fungal composition structures in the seedling stage, but only drain depth significantly altered soil microbial composition structures in the FBS stage. Based on the null model, the assembly of soil microbial communities was mainly driven by stochastic processes. The contributions of the deterministic process for soil bacterial community assembly at the seedling stage and FBS stage were 18.1% and 22.1%, respectively. In contrast, soil fungal community assembly was mainly determined by dispersal limitation and drift. [ABSTRACT FROM AUTHOR]

The intermediate fluid thermoelectric generator (IFTEG) represents a novel approach to power generation, predicated upon the principles of gravity heat pipe technology. Its key advantages include high-power output and a compact module area. The generator's performance, however, is influenced by the variable exhaust parameters typical of automobile operation, which presents a significant challenge in the design process. The present study establishes a mathematical model to optimize the design of the IFTEG. Our findings suggest that the optimal module area sees substantial growth with an increase in both the exhaust heat exchanger area and the exhaust flow rate. Interestingly, the optimal module area appears to demonstrate a low sensitivity to changes in exhaust temperature. To address the challenge of determining the optimal module area, this study introduces the concept of peak power deviation. This method posits that any deviation from the optimal module area results in an equivalent power deviation. For instance, with an exhaust heat exchanger area of 1.6 m2, the minimum peak power deviation is 27.5%, corresponding to a design module area of 0.124 m2. As such, the actual output power's deviation from the maximum achievable output power will not exceed 27.5% for any given set of exhaust parameters. This study extends its findings to delineate the relationship between the optimal design module area and the exhaust heat exchanger area. These insights could serve as a useful guide for the design of future power generators. [ABSTRACT FROM AUTHOR]

Flyers driven by various technologies have been widely used as effective shock loading techniques in the ignition of energetic materials, space debris impact modeling, equation of state measurement, etc. However, their flying characteristics have the greatest influence on application reliability. The flying velocity, as well as the flyer's planarity and integrity, are crucial characteristics. Therefore, mainstream flyer-driving technologies are examined in this study, and research progress in investigation approaches on flyer velocity and morphology are reviewed. Furthermore, for each flyer-driving technique, the affecting factors of flyer velocity and morphology are summarized. Current research deficiencies are highlighted, and future research directions are discussed, including the parallel coupling of various driving principles, quantitative characterizations of the flyer's planarity and integrity, and the physical model matching the flying process. [ABSTRACT FROM AUTHOR]