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Despite impressive merits of complementary charge‐storage mechanisms for aqueous Zn‐ion hybrid micro‐supercapacitors (ZHMSCs), it remains a challenge to solve dendrite and parasitic reactions issues of Zn anodes. Herein, a kinetics‐boosted strategy of Zn2+ transport and desolvation of hydrated Zn2+ is proposed by engineering zwitterionic P(AM‐co‐SBMA) hydrogel electrolyte (PASHE) for highly reversible Zn plating/stripping. Mechanically robust and chemically anchored PASHE features zwitterionic groups for constructing ion migration channels and immobilizing water molecules, which accelerates Zn2+ migration for an ultrahigh transfer number (0.84) and alleviates water‐related parasitic reactions. Theoretical calculations combined with experimental results reveal that sulfobetaine sulfonate anions endow PASHE with improved desolvation kinetics and the ability to coordinate Zn2+ flux and electric field distributions at the electrolyte–electrode interface. Thus, Zn anodes exhibit excellent electrochemical performance involving high average coulombic efficiency of 99.4% in Zn|PASHE|Cu cell as well as high cumulative capacity of 2000 mAh cm−2 (20 mA cm−2, 1 mAh cm−2) and depth of discharge of 80.9% (20 mA cm−2, 10 mAh cm−2) in Zn|PASHE|Zn cells. Furthermore, ZHMSCs based on PASHE deliver excellent flexibility and cyclability for energy‐storage applications. This work provides useful insights on hydrogel electrolyte engineering for developing high‐performance Zn anodes and derived energy‐storage devices.

Context: Selenium nanoparticles (SeNPs) have attracted worldwide attention due to their unique properties and potential bioactivities. Considering that hawthorn is both a traditional medicine and a common edible food, hawthorn fruit extract (HE) was chosen as a reductant to prepare SeNPs.Objective: SeNPs were synthesized by using an aqueous HE as a reductant and stabilizer. The antitumor activities and potential mechanisms of SeNPs were explored by using a series of cellular assays.Materials and methods: The HE mediated SeNPs (HE-SeNPs) were examined using various characterisation methods. The cytotoxicity was measured against HepG2 cells after treated with 0, 5, 10 and 20 μg/mL of HE-SeNPs for 24 h. Annexin V-FITC/PI staining analysis was performed to observe the apoptosis of HepG2 cells. Additionally, mitochondrial membrane potential (MMP), intracellular reactive oxygen species (ROS) levels were evaluated. Finally, the protein expression levels of caspase-9 and Bcl-2 were identified by Western blot.Results: The mono-dispersed and stable SeNPs were prepared with an average size of 113 nm. HE-SeNPs showed obvious antitumor activities towards HepG2 cells with an IC50 of 19.22 ± 5.3 μg/mL. Results from flow cytometry revealed that both early and total apoptosis rates increased after treating with HE-SeNPs. After cells were treated with various concentrations of HE-SeNPs (5, 10 and 20 μg/mL) for 24 h, the total rate increased to 7.3 ± 0.5, 9.7 ± 1.7 and 19.2 ± 1.6%, respectively. Meanwhile, treatment of HE-SeNPs up-regulated intracellular ROS levels and reduced the MMP. In addition, HE-SeNPs induced the up-regulation of caspase-9 and down-regulation of Bcl-2.Discussion and conclusions: HE-SeNPs induced intracellular oxidative stress and mitochondrial dysfunction to initiate HepG2 cell apoptosis through the mitochondrial pathway. Therefore, HE-SeNPs may be a candidate for further evaluation as a chemotherapeutic agent for human liver cancer.

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Measuring the performance of Freight Villages (FVs) has important implications for logistics companies and other related companies as well as governments. In this paper we apply Data Envelopment Analysis (DEA) to measure the performance of European FVs in a purely data-driven way incorporating the nature of FVs as complex operations that use multiple inputs and produce several outputs. We employ several DEA models and perform a complete sensitivity analysis of the appropriateness of the chosen input and output variables, and an assessment of the robustness of the efficiency score. It turns out that about half of the 20 FVs analyzed are inefficient, with utilization of the intermodal area and warehouse capacity and level of goods handed the being the most important areas of improvement. While we find no significant differences in efficiency between FVs of different sizes and in different countries, it turns out that the FVs Eurocentre Toulouse, Interporto Quadrante Europa and GVZ Nürnberg constitute more than 90% of the benchmark share.

Flexible and wearable devices are important parts toward the realization of artificial intelligence and have an irreplaceable advantage over traditional rigid sensors. In this work, a film with double surface structure is prepared by using sandpaper and the leather with a rhombic structure as a mold, thereby obtaining a sandwich structure resistive type pressure sensor, which has high sensitivity (77.78 kPa−1, 24 Pa minimum detection) and wide detection range (0.024–230 kPa). The sensors have fast response time (30 ms) and high reliability over 5000 repetitive cycles. The humidity sensor is printed on the top layer of the sensor by using screen printing and inkjet printing technique, and the sandwich structure humidity and pressure sensor is obtained. The humidity sensors show the sensitivities of 0.137/%, 1.57/%, and 11.145/% in the relative humidity range from 25 to 55%, 55 to 70%, and 70 to 80%, respectively. Such sensors not only have excellent capabilities in pressure and humidity detection, but also avoid the complex process of multiple single‐function devices stacked on each other. The applications of sensors in monitoring artery pulse waves, detecting spatial pressure distribution, and sweat is demonstrated.

Despite the physicochemical advantages of two-dimensional (2D) carbons for supercapacitors, the inappropriate texture within 2D carbon materials suppresses the charge storage capability. Reported here are heteroatom-rich carbon sheets with the overall network engineered by molecular structure modulation and subsequent chemical activation of a three-dimensional (3D) cross-linked polymer. The 3D-to-2D reconstruction mechanism is unveiled. The architecture with a large active surface, fully interpenetrating and conductive network, and rich surface heteroatoms relieves well the ionic diffusion restriction within thick sheets and reduces the overall resistance, exhibiting fast transport kinetics and excellent stability. Indeed, high gravimetric capacitance (281.1 F g–1 at 0.5 A g–1), ultrahigh retention rate (92.5% at 100 A g–1), and impressive cyclability (89.7% retention after 20 000 cycles) are achieved by this material. It also possesses a high areal capacitance of 3.56 F cm–2 at 0.5 A g–1 under a high loading of 25 mg cm–2. When coupled with the developed dual cross-linked hydrogel electrolyte (Al-alginate/poly­(acrylamide)/sodium sulfate), a quasi-solid-state supercapacitor delivers an energy density of 28.3 Wh kg–1 at 250.1 W kg–1, which is significantly higher than those of some reported aqueous carbon-based symmetric devices. Moreover, the device displays excellent durability over 10 000 charge/discharge cycles. The proposed cross-linked polymer strategy provides an efficient platform for constructing dynamics-favorable carbon architectures and attractive hydrogel electrolytes toward improved energy supply devices.