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Over the past decades, Na0.5Bi0.5TiO3 (NBT)-based ceramics have received increasing attention in energy storage applications due to their high power density and relatively large maximum polarization. However, their high remnant polarization (Pr) and low breakdown field strength are detrimental for their practical applications. In this paper, a new solid solution (1−x)Na0.5Bi0.5TiO3–xCaHfO3 (x = 0.04, 0.08, 0.12, 0.16) was constructed by introducing CaHfO3 into NBT, and thus was prepared using a conventional solid-state reaction. With the addition of CaHfO3, the disorder of the structure increased, A-site vacancies formed, and thus oxygen vacancies were suppressed due to the replacement of the Na+ by Ca2+, resulting in the enhanced relaxation behavior and the reduced Pr, the refined grain, and improved breakdown strength. Furthermore, an optimal recoverable energy storage density (Wrec) of 1.2 J/cm3 was achieved in 0.92Na0.5Bi0.5TiO3–0.08CaHfO3 ceramics under the breakdown strength of 140 kV/cm, which is mainly attributed to the resultant defect of Na+ vacancy. [ABSTRACT FROM AUTHOR]

The surface texture of asphalt pavement has a significant effect on skid resistance performance. However, its contribution to the performance of skid resistance is non‐homogeneous and subjects to local validity. There are also a few deep learning models that take into account the effective contact texture region. This paper proposes a convolutional neural network model based on the effective contact texture region, containing macro‐ and micro‐scale awareness sub‐modules. In this study, the asphalt mixture with varying gradations was designed to accurately obtain the effective contact texture region. Then, the textures were disentangled into macro‐ and micro‐texture scales by applying the fast Fourier transform and fed into the model for training. Finally, the area of effective contact texture region was calculated, and the effective contact ratio parameter was then proposed using the triangulation algorithm. The results showed that the effective contact texture area of pavement varies by the asphalt mixture type. The effective contact ratio parameter exhibited a significant positive correlation (Pearson correlation coefficient is 0.901, R2= 0.8129) with skid resistance performance and was also influenced by key sieve aggregate content from 2.36 to 4.75 mm. The data of effective contact texture region following disentanglement significantly released the model performance (the relative error dropped to 1.81%). The model exhibited improved precision and performance, which can be utilized as an efficient, non‐contact alternative method for skid resistance analysis. [ABSTRACT FROM AUTHOR]

In the present study, the effect of elastomer ratios in solution-based mixtures on the formation of the phase structure and properties of compositions based on butyl rubber, chlorobutyl rubber, and ethylene-propylene-diene rubber was investigated. This work determined the influence of the elastomer ratios in uncured blends and their impact on the patterns of phase structure formation in multicomponent polymer systems, alterations in molecular mobility, and their influence on ozone resistance. Attenuated total reflectance – Fourier transform infrared spectroscopy was employed to analyze the chemical structure of the polymer surfaces. The influence of blend ratio (mass percentage ratios of 100/0, 80/20, 60/40, 50/50, 40/60, 20/80, and 0/100) on the phase structure and surface ozone oxidation was studied. The green strengths of the blends of ethylene-propylene-diene rubber and butyl/chlorobutyl rubbers were studied over a wide range of blend ratios. [ABSTRACT FROM AUTHOR]

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As one of the important internal curing agents for cement-based materials, inorganic/organic composite water absorbing materials, which has hydrophilic groups and three-dimensional network structures, exhibits excellent water absorption, water retention, and water release properties. By introducing inorganic/organic composite water absorbing materials into cement-based materials, their water absorption and release characteristics can automatically adjust the internal relative humidity of cement-based materials, promote hydration reactions, reduce self shrinkage and early cracking of cement-based materials, and thereby improve mechanical properties and durability. The preparation methods, structural characteristics and absorption/desorption behavior of inorganic/organic composite internal curing materials (CICA) were introduced. The impact on the hydration process, microstructure, macroscopic properties and durability of cement-based materials were summarized. The development prospects of CICA in concrete applications were prospected, providing theoretical guidance and technical reference for the application of CICA in cement-based internal curing. [ABSTRACT FROM AUTHOR]

Interpenetrating polymer networks (IPNs) possessing a wide damping temperature range are commonly employed as damping materials that are applied in numerous fields. But IPNs will gradually appear to fatigue microcracks and fracture when long‐term in the energy absorption and dissipation. So, the ability for IPNs to recover from damage is necessary that can considerably prolong their service life. Based on polyurethane elastomer and cross‐linked epoxy, several innovative self‐healing IPNs are designed and prepared in this research. The IPNs containing dynamic disulfide bond exhibit favorable damping and self‐healing properties. In detail, the loss factor of IPN‐80/20 is beyond 0.3 at temperatures between −0.8 and 65.5 °C that covers the operating temperature range at room temperature. What is more, The PU/EP IPNs also have excellent shape memory properties, self‐healing ability, and thermal stability. [ABSTRACT FROM AUTHOR]

Asphalt in damp-heat and saline-alkali areas is prone to damage, which resulting in fatigue failure of the mixture. However, the aging damage of asphalt in these areas has not been paid enough attention, and there is a lack of effective evaluation method for asphalt's fatigue performance. In this paper, the base asphalt and SBS-modified asphalt were immersed in several solutions (water, NaCl and Na2CO3) to simulate aging conditions and the frequency sweep test was employed to determine the viscoelasticity properties of the asphalt. And the fatigue properties of the asphalt were analysed by the simplified viscoelastic continuum damage model. The microstructural and chemical evolution of asphalt was investigated by SEM, FTIR, the pH value and total organic carbon tests. After being immersed, the anti-deformation properties of two asphalts were strengthened. The solution erosion led to an increased loss rate of the integrity factor C*, and resulting in weakened fatigue properties of asphalt. The oxygen-containing functional group gradually increased with the extension of immersion. There were chemical interactions in addition to physical interface disruption during the immersion process. Moreover, the influence of Na2CO3 solution on asphalt ranked first due to the highest molar concentration of Na+ and the OH− produced by hydrolysis of ${\rm CO}_3^{2-}$ C O 3 2 − . [ABSTRACT FROM AUTHOR]