Highly conductive and stretchable fibers have recently attracted increasing attention owing to their potential for application in flexible wearable electronics. Carboxylated carbon nanotubes (c-CNTs) are coated onto flexible fibers as a convenient way of fabricating wearable strain sensors. However, the conductivity of a c-CNT is reduced due to the destruction of the graphitized structure of the CNT during carboxylation. It still remains a significant challenge to endow c-CNT composite fibers with high conductivity. In this study, highly conductive fibers were prepared by coating metal ion-linked c-CNTs onto polyurethane (PU) fibers in order to improve the electron transport rate between the c-CNTs. The metal-coordination junctions formed by Fe2+ ions and carboxyl significantly enhanced the conductivity of the PU/CNT@Fe2+ fibers (up to 72 S m−1). The high conductivity is the result of coordination junctions with strong electronic state coupling facilitating electron transport, which was proved by density functional theory calculations. The resulting coordination effect enhanced the interaction between the c-CNTs, which made the conductive network more flexible. The strain sensor based on PU/CNT@Fe2+ fibers exhibited high sensitivity (gauge factor = 36 at 50% strain), a large strain range, inconspicuous drift and durability. The fibrous strain sensor was successfully used to monitor joint movement and facial expression.

Except for the narrow ZGNRs, 1-ZGNR and 2-ZGNR, odd ZGNRs possess small current regardless of the bias applied and even ZGNRs have much larger current and behave as a resistor.

Excessive carbon emissions will cause irreversible damage to the human living environment. Therefore, carbon neutrality has become an inevitable choice for sustainable development. Marine fishery is an essential pathway for biological carbon sequestration. However, it is also a source of carbon emissions. From this perspective, an in-depth assessment of the performance of carbon emissions and sinks from marine fisheries is required to achieve the goal of carbon neutrality. This paper measured the carbon emissions, carbon sinks, and net carbon emissions of marine fisheries in nine coastal provinces of China from 2005 to 2020 for the first time. Based on the calculation results, the log-mean decomposition index method was used to analyze the driving factors of net carbon emissions. The results suggested that, from 2005 to 2020, both the carbon emissions and carbon sinks of China’s marine fisheries increased, and the net carbon emissions showed a downward trend. There were variations in the performance of carbon emissions, carbon sinks, and net carbon emissions in different provinces, and only Shandong could consistently achieve carbon neutrality. Fujian and Liaoning achieved carbon neutrality in 2020. In terms of the contribution of each factor, the industrial structure was the main positive driver, and carbon intensity was the main negative driver. Based on the empirical results, this paper suggested increasing the implementation of the carbon tax policy, establishing a farming compensation mechanism and promoting carbon emissions trading and international blue carbon trading. The results could give a reference for the energy conservation and emission reduction of marine fisheries while enhancing the ecological benefits of their carbon sinks and helping to achieve the carbon neutrality target.

Electron transport through a series of molecular junctions (CTP-M) composed of two carboxyl thiophenols (CTPs) on each gold electrode coordinating with a divalent metallic ion (M) in the center has been investigated using the density functional theory combined with nonequilibrium Green’s function (DFT-NEGF) approach. The electronic structure, I–V characteristics, density of states (DOS), and transmission spectra of all CTP-M models have been calculated and compared to the junction without the metallic ion (CTP-H). While strong electronic coupling is established in the coordination structure, the transportation is efficient, showing higher junction conductance as compared to CTP-H. On the contrary, weak electronic coupling is formed between the carboxyl groups and the alkali metal ions (CTP-Mg and CTP-Ca) due to a twisted configuration, exhibiting smaller junction conductance. The strong dependence of the current on the coordination complex has been interpreted with the fine structure of the tunneling barrier. H-bonds result in a bump in the tunneling barrier profile, impeding the electron transfer. When the transition metal ions were incorporated into the molecular junction, the central part of the tunneling barrier turns into an energy well, facilitating the electron transfer. This study provides an effective method to control the interface electron transport required in the construction of flexible wearable electronic devices and functional electronic molecular devices.