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The fatigue performance of the asphalt mixture was the main focus of this study, with five typical factors—phase angle, cumulative dissipated energy, failure strain, failure stiffness modulus, and strain rate—identified as potential design indexes. The effect of asphalt content on the parameters under different gradation and stress ratios was tested. It was observed that the selected parameters exhibited varying levels of sensitivity and relevance to the fatigue behavior of asphalt mixtures under cyclic loads. By comparison, the strain rate proved sensitive to the asphalt content and independent of the other parameters, namely aggregate gradations and stress ratio, thus establishing the strain rate as a critical design index based on fatigue performance. On this basis, a design method based on the fatigue performance for the asphalt mixtures is herein proposed. It was confirmed that the asphalt mixture formulated using the proposed method exhibited enhanced fatigue endurance compared to those designed using the conventional method. [ABSTRACT FROM AUTHOR]

In the planar flow casting process of amorphous strips, the flow behavior of molten metal and the inclusion content in the crucible are crucial to the morphology and magnetic properties of the material. This study conducts a comparative analysis of the effects of non-immersed and immersed funnels, as well as various funnel structures, on the fluid flow and inclusion removal efficiency in the crucible by integrating numerical and physical models. The findings reveal that for the same pouring flow rate, the diameter of the liquid column in non-immersed pouring conditions is smaller than that of the funnel outlet, leading to a faster injection flow velocity. As a result, the melt in the crucible is subjected to severe impacts, accompanied by an increased possibility of slag entrapment. Conversely, immersed pouring substantially reduces the velocity of the molten metal at the funnel outlet, thereby extending the residence time in the crucible and diminishing the volume of the dead zone. Additionally, the molten metal backflows due to the negative pressure formed in the inner chamber of the funnel. The design of a trumpet-shaped funnel increases the effective volume while reducing the height of the backflow fluid, consequently reducing the velocity of the molten metal at the funnel outlet and prolonging the residence time. Compared to the conventional pouring process with the non-immersed funnel, the outlet velocity is reduced from 1.1 m/s to 0.12 m/s by adopting the immersed funnel with an inverted trapezoidal trumpet structure. This reduction results in a stable flow state, a 9.69% reduction in the dead zone volume fraction, and a 22.96% increase in average inclusion removal efficiency. These improvements demonstrate that a crucible funnel with a well-designed structure and the implementation of an immersion process can significantly improve the metallurgical effects in the planar flow casting process. [ABSTRACT FROM AUTHOR]

Stretchable dielectric polymer with high dielectric constant is a major component for electroluminescent devices. However, the intrinsic instability toward water severely limits their further applications in marine environment. Here, a transparent, underwater stable, and self‐healable dielectric material with high dielectric constant is reported. The electroluminescent device based on this newly designed fluoropolymer can work stably in aqueous conditions. There is no significant attenuation of mechanical and optoelectronic property after immersed in water and salty water for a month. The intrinsic self‐healing ability of the device makes it robust and resilient against unexpected minor or severe damages. [ABSTRACT FROM AUTHOR]

Star field affiliation is an important part of ancient Chinese gazetteers. The gazetteers of Taiwan in the Qing Dynasty presented many 'different opinions' about the star field affiliation of Taiwan. These different opinions illustrate the difficulty of self-consistency in traditional Chinese star field affiliation theory and reflect the influence of the concept of grand unification on traditional Chinese geographical knowledge. During the Qianlong period, with the introduction of Western surveying and mapping knowledge, the sundial began to replace star field affiliation and became a new geographical positioning theory. Taiwan, whose geographical positioning also completed the transformation from the star field affiliation to sundial theory at the end of the Qing Dynasty, witnessed the replacement of traditional Chinese place knowledge with cosmopolitan knowledge. Looking back at the writings regarding the star field affiliation in Taiwan gazetteers in the Qing Dynasty, there was both debate and consensus. [ABSTRACT FROM AUTHOR]

Dielectric elastomer actuators (DEAs) with large actuation strain and high energy density are highly desirable for actuating soft robots. However, DEAs usually require high driving electric fields (>100 MV m−1) to achieve high performances due to the low dielectric constant and high stiffness of dielectric elastomers (DEs). Here, we introduce polar fluorinated groups and nanodomains aggregated by long alkyl side chains into DE design, simultaneously endowing DE with a high dielectric constant and desirable modulus. Our DE exhibits a maximum area strain of 253% at a low driving electric field of 46 MV m−1. Notably, it achieves an ultrahigh specific energy of 225 J kg−1 at only‍‌ ‌‌40‍‌ MV m−1, around 6 times higher than natural muscle and twice higher than the state-of-the-art DE. Using our DE, soft robots reach an ultrafast running speed of 20.6 BL s−1, 60 times higher than that of commercial VHB 4910, representing the fastest DEA-driven soft robots ever reported. Dielectric elastomer actuators require high driving electric fields to achieve high performances for soft robots due to their low dielectric constant and high stiffness. Here, the authors introduce polar fluorinated groups and nanodomains aggregated by long alkyl side chains into the dielectric elastomer design to overcome these issues and develop fast soft robots. [ABSTRACT FROM AUTHOR]

Rapid underwater self‐healing elastomers with high mechanical strength at ambient temperature are highly desirable for dangerous underwater operations. However, current room temperature self‐healing materials have shortcomings, such as low healing strength (below megapascal), long healing time (hours), and decay of healing functions in harsh environments (salty, acidic, and basic solutions), limiting their practical applications. Herein, it is introduced water‐stable Debye forces and high‐density nano‐sized physical crosslinking into one network to achieve a stiff yet rapid self‐healing elastomer that can work in harsh aqueous environments. The obtained elastomer possesses a high Young's modulus of 48 MPa (24 times than that of natural elastomer), and it can achieve 90% of maximum mechanical strength healing for 10 s at ambient temperature in all types of harsh aqueous conditions, outperforming three orders of magnitudes in healing speed of reported room‐temperature self‐healing elastomers with Young's modulus over 10 MPa. The new stiff yet rapidly healable elastomers have great potential in emergent repair in urgent and dangerous cases. [ABSTRACT FROM AUTHOR]