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Summary The further development of flexible electronics inevitably requires conductive materials to have numerous foldable properties; however, that has not been realized. Here, inspired by silkworm cocooning processes, we prepare a super-foldable conductive carbon material with layered nanofiber network structures through an improved electrospinning/carbonization technique. It can remarkably bear 1,000,000 times repeated true-folding without structural damage and conductivity fluctuations. The root of such performance breakthrough is revealed through real-time SEM folding observation and mechanical simulations. Its structures featuring appropriate pores, non-crosslinked junctions, slidable nanofibers, separable layers, and a compressible network can act synergistically to generate a e-like folding construction at crease under true-folding, which can completely disperse stress via bulged layers, dispersed arcs, and slidable grooves in e. Consequently, each nanofiber avoids directly facing with 180° folding when the whole material is true-folded. This work embodies structure innovation, performance breakthrough, and mechanism reveal, which has great scientific significance and application prospects.

Poria cocos is a traditional Chinese medicine (TCM) that can clear dampness, promote diuresis, and strengthen the spleen and stomach. Poria cocos has been detected in many TCM compounds that are used for COVID-19 intervention. However, the active ingredients and mechanisms associated with the effect of Poria cocos on COVID-19 remain unclear. In this paper, the active ingredients of Poria cocos, along with their potential targets related to COVID-19, were screened using TCMSP, GeneCards, and other databases, by means of network pharmacology. We then investigated the active components, potential targets, and interactions, that are associated with COVID-19 intervention. The primary protease of COVID-19, Mpro, is currently a key target in the design of potential inhibitors. Molecular docking techniques and molecular dynamics simulations demonstrated that the active components of Poria cocos could bind stably to the active site of Mpro with high levels of binding activity. Pachymic acid is based on a triterpene structure and was identified as the main component of Poria cocos; its triterpene active component has low binding energy with Mpro. The pachymic acid of Mpro activity was further characterized and the IC50 was determined to be 18.607 μmol L−1. Our results indicate that pachymic acid exhibits a certain inhibitory effect on the Mpro protease.

In this work, three novel MgO-SiO2 composite catalysts with inverted structure have been synthesized via a facile and scalable strategy by means of the incipient wetness impregnation of the silica sol onto MgO precursors with different morphologies, and evaluated for the one-step conversion of ethanol to 1,3-butadiene. The prepared flower-like MgO-SiO2 composite catalysts exhibited highly enhanced catalytic activity than those catalysts synthesized from MgO precursors with nanodisks and nanosheets morphologies. Characterization results based on XRD, FT-IR, UV–vis, BET, CO2-TPD, NH3-TPD, ethanol-TPD, and 29Si MAS NMR revealed that unique layered flower-like architectures may facilitate the formation of interfacial Mg-O-Si chemical bond in binary MgO-SiO2 composite catalysts which are mainly responsible for the superior activity. This study presents a new strategy to design and develop the catalyst for efficient conversion of bio-ethanol to 1,3-butadiene by morphological control of MgO-SiO2 bifunctional catalysts.