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The fiber-reinforced polymers (FRP) bar is a promising solution to problems caused by steel rebar corrosion in concrete. To assess the service life of the FRP bar based on accelerated test results, it is crucial to have a reliable model. Here, a modified exponential (MEP) model is proposed based on the Avrami equation. The Avrami equation provides a theoretical foundation for the empirical exponential (EP) model and does not a priori fix the power of the exposure time to one. A database containing 903 data points from 74 groups of test specimens is assembled to compare the reliability of the MEP model vis-a-vis the EP, single logarithmic, double logarithmic, and power function models. The combination of Root Mean Square Error (RMSE), the Mean Absolute Error (MAE), and the coefficient of determination (R2) criteria is proposed for assessing model reliability. It is shown that in certain cases the combined criteria, versus R2 alone, significantly increase the number of test groups meeting the acceptable performance limit. Observed test data aberrations are found to have minor influence on the results of the EP model, but they significantly influence the results of the other four models. The EP model generally predicts the lowest activation energy and the smallest strength retention for similar groups of bars, while the predicted values of the other four models exhibit a relatively small difference. The difference between the predicted strength retention values of the EP and MEP models shows an increasing trend with the increase of the absolute value of (1 − n), where n is the power of the exposure time in the MEP model. [ABSTRACT FROM AUTHOR]

Li metal has emerged as a promising anode material for high energy density batteries, due to its low electrochemical potential and high specific capacity of 3860 mAh·g−1. These characteristics make it an attractive choice for electric vehicles and power grids. However, Li-metal batteries are plagued by dendrite issues stemming from the high reactivity of Li metal, which can ultimately result in battery failure or even safety concerns. To overcome this challenge, various strategies have been proposed to prevent dendrite formation and enhance the safety of Li-metal batteries. This review critically examines the recent progress in the development of dendrite-free Li-metal batteries, with a particular emphasis on advanced approaches of 3D Li metal host construction. Our goal is to provide a comprehensive overview of the 3D hosts for suppressing Li dendrites and to offer guidance for the future development of superior Li metal batteries. [ABSTRACT FROM AUTHOR]

As one of the key components of solid-contact ion-selective electrodes (SC-ISEs), the SC layer plays a crucial role in electrode performance. Carbon materials, known for their efficient ion–electron signal conversion, chemical stability, and low cost, are considered ideal materials for solid-state transducing layers. In this review, the application of different types of carbon materials in SC-ISEs (from 2007 to 2023) has been comprehensively summarized and discussed. Representative carbon-based materials for the fabrication of SC-ISEs have been systematically outlined, and the influence of the structural characteristics of carbon materials on achieving excellent performance has been emphasized. Finally, the persistent challenges and potential opportunities are also highlighted and discussed, aiming to inspire the design and fabrication of next-generation SC-ISEs with multifunctional composite carbon materials in the future. [ABSTRACT FROM AUTHOR]

Catalytic processes are the dominant driving force in the chemical industry, proper design and fabrication of three-dimensional (3D) catalysts monoliths helps to keep the active species from scattering in the reaction flow, improve high mass loading, expose abundant active catalytic sites and even realize turbulent gas flow, greatly improving the catalytic performance. Three-dimensional printing technology, also known as additive manufacturing, provides free design and accurate fabrication of complex 3D structures in an efficient and economic way. This disruptive technology brings light to optimizing and promoting the development of existing catalysts. In this mini review, we firstly introduce various printing techniques which are applicable for fabricating catalysts. Then, the recent developments in 3D printing catalysts are scrutinized. Finally, challenges and possible research directions in this field are proposed, with the expectation of providing guidance for the promotion of 3D printed catalysts. [ABSTRACT FROM AUTHOR]

Carbon materials have been widely used as electrode materials for supercapacitors, while the current carbon precursors are mainly derived from fossil fuels. Biomass-derived carbon materials have become new and effective materials for electrodes of supercapacitors due to their sustainability, low pollution potential, and abundant reserves. Herein, we present a new biomass carbon material derived from water hyacinth by a novel activation method (combination of KOH and HNO3 activation). According to the electrochemical measurements, the material presents an ultrahigh capacitance of 374 F g−1 (the current density is 1 A g−1). Furthermore, the material demonstrates excellent rate performance (105 F g−1 at a higher density of 20 A g−1) and ideal cycling stability (87.3% capacity retention after 5000 times charge–discharge at 2 A g−1). When used for a symmetrical supercapacitor device, the material also shows a relatively high capacity of 330 F g−1 at 1 A g−1 (a two-electrode system). All measurements suggest the material is an effective and noteworthy material for the electrodes of supercapacitors. [ABSTRACT FROM AUTHOR]