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The micro-mechanical properties of asphalt surfaces are significantly impacted by short-term aging during construction and long-term aging in service. This, in turn, affects macroscopic characteristics such as asphalt-aggregate adhesion and water stability of asphalt mixtures. The study investigated different aging processes had different impacts on the micromechanical properties of the asphalt on the surface. The short-term aging process had the most significant effects, while the subsequent long-term aging had similar but less important effects. The adhesion, surface energy, and Young's modulus of five different types of asphalt using atomic force microscopy (AFM) in their original state, after short-term aging through the Rolling Thin Film Oven Test (RTFOT), and after long-term aging through the RTFOT+Pressure Aging Vessel (PAV). The results showed that ZH and SK asphalts had a distinct ''bee structure'', and aging had varying effects on adhesion, surface energy, and Young's modulus in different areas (peak, valley, and other region). Before and after asphalt aging, the adhesion and surface energy approximately followed the order other region > peak > valley, while Young's modulus approximately followed the peak>valley> other region. This indicates that the bumpy ''bee structure'' does not always correspond to higher modulus or lower adhesion. It was also found that ZH asphalt and SK asphalt with a ''bee structure'' exhibited better aging resistance compared to KL asphalt without a ''bee structure''. The study also revealed that aging led to decreased adhesion and surface energy, while increasing Young's modulus. This finding indicates that as asphalt ages, adhesion decreases and asphalt elasticity increases. Additionally, it was observed that the modified asphalt showed less change in adhesion, surface energy, and Young's modulus after aging compared to the matrix asphalt, indicating that SBS modifiers contribute to improving the aging resistance of asphalt. These results will provide a good reference for understanding the microscopic changes in asphalt aging properties.

The quantum well diode (QWD) performs a dual role, functioning both as an emitter and a detector due to its unique feature of spectral overlap between emission and detection spectra. This dual functionality positions QWDs as promising candidates in the realm of multifunctional sensors. Furthermore, the well-established maturity of optical fiber communication, grounded in its intrinsic property of total reflection, makes it an ideal transmission medium for QWD sensing signals. Leveraging the coexisting emission and detection capabilities of QWDs, we have constructed a sensing system in this article. This system utilizes a QWD, which is stimulated to emit light, with the emitted light traveling through a specified length of optical fiber. A specialized load-bearing film, featuring an aluminum membrane on its rear to act as a mirror and an object of known weight on its front, induces deformation in the film, thereby altering the characteristics of the reflected light. This modulated light is subsequently captured by the QWD via the optical fiber, enabling the computation of the weight of the object. In this article, the QWD's emission peak is around 522 nm, and its detection range extends from 370 to 530 nm. Furthermore, by employing the appropriate approach, integrating QWD with optical fibers can be extended to sensing and measuring various physical quantities such as temperature, solution concentration, wind speed, and more. The advantages of QWDs include cost-effectiveness, multifunctionality, portability, and environmental friendliness. This technology represents a promising avenue for sensor control in the era of the Internet of Things. [ABSTRACT FROM AUTHOR]

Compared with heavy metal catalysts, metal-free catalysts that activate persulfate (PS) for controlling organic pollutants are more economical, environmentally friendly, and safer for human health. Utilizing ZIF-8 particles as templates and polyphosphazene as the precursor, hollow N, P, and O tri-doped carbon microspheres (NPOC) with a hierarchical pore structure were successfully synthesized from ZIF-8@polyphosphazene. Their morphology and structure were investigated by SEM, TEM, TGA, XPS, BET, and FT-IR. Otherwise, NPOC were used as catalysts to activate PS for the oxidative degradation of tetracycline. The dosage of catalyst and oxidant, tetracycline concentration, carbonization temperature, and pH can all have a substantial influence on the oxidative degradation of tetracycline. Free radical testing by EPR reveals that HO˙ and SO4˙− are generated and the radical pathway is dominant in the oxidative degradation process. NPOC exhibited superior catalytic oxidation performance and good reusability, indicating their potential for application for eliminating TC from aqueous solution. [ABSTRACT FROM AUTHOR]