Construction of self-healing materials with improved mechanical performance is a great challenge. A strong and tough self-healing composite is fabricated via in situ growth of zeolitic imidazole framework-8 (ZIF-8) nanocrystals in imidazole-containing polymer networks. By adjusting the stoichiometric ratio of the zinc salt to 2-methylimidazole, composites with various mechanical performances are obtained.
View Article and Find Full Text PDFStudying the commercial dynamics during the COVID-19 recession could help deepen our understanding of how the pandemic damages the commercial economy and how to against the pandemic. This study aims to explore the vulnerability and adaptation of commercial centers using a weekly consumption data of UnionPay cards in Shanghai. A vulnerability index and multiscale geographically weighted regressions (MGWR) are employed.
View Article and Find Full Text PDFTransp Res D Transp Environ
September 2022
COVID-19 has swept the world, and the unprecedented decline in transit ridership has been noticed. However, little attention has been paid to the resilience of the transportation system, particularly in medium-sized cities. Drawing upon a light rail ridership dataset in Salt Lake County from 2017 to 2021, we develop a novel method to measure the vulnerability and resilience of transit ridership using a Bayesian structure time series model.
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