• An efficient method was proposed to prepare perpendicular graphene nano-sheets in flexible sensor electrode. • The nanostructure in carbon electrode was fabricated to further enhance the sensitivity of sensor device using a simple method. • The capacitance showed high performance within only 50-μm dielectric thickness, and an exciting phenomenon of decreasing in capacitance was analyzed. ABSTRACT Graphene-based materials on wearable electronics and bendable displays have received considerable attention for the mechanical flexibility, superior electrical conductivity, and high surface area, which are proved to be one of the most promising candidates of stretching and wearable sensors. However, polarized electric charges need to overcome the barrier of graphene sheets to cross over flakes to penetrate into the electrode, as the graphene planes are usually parallel to the electrode surface. By introducing electron-induced perpendicular graphene (EIPG) electrodes incorporated with a stretchable dielectric layer, a flexible and stretchable touch sensor with "in-sheet-chargestransportation" is developed to lower the resistance of carrier movement. The electrode was fabricated with porous nanostructured architecture design to enable wider variety of dielectric constants of only 50-μm-thick Ecoflex layer, leading to fast response time of only 66 ms, as well as high sensitivities of 0.13 kPa −1 below 0.1 kPa and 4.41 MPa −1 above 10 kPa, respectively. Moreover, the capacitance-decrease phenomenon of capacitive sensor is explored to exhibit an object recognition function in one pixel without any other integrated sensor. This not only suggests promising applications of the EIPG electrode in flexible touch sensors but also provides a strategy for internet of things security functions.

Harvesting energy from water flow based on liquid–solid contact electrification has been receiving intensive attention recently. However, due to the high deformability of water, challenges remain on exploring the dynamic motion of water in relation to the electrical output characteristic of water‐based triboelectric nanogenerator (TENG). Herein, by measuring the electrical output of a water droplet‐driven TENG (Wd‐TENG) along with observing the dynamics of the droplets by a high‐speed camera, a robust working mechanism of the Wd‐TENG is proposed, considering droplet spread, rebound, slide, and coalescence on the solid surface during the triboelectric cycle. It is demonstrated that the spread–rebound motion of droplet upon impact on the triboelectric layer surface results in one positive–negative current peak and the detachment of the droplet from the surface leads to another negative current peak. Droplet coalescence is also observed and found to cause larger negative peak when the merged droplet leaves the surface. The proposed mechanism is sufficiently proved by the results under different droplet dripping rates, sizes, surface wetting properties, and types of liquid. These findings provide an extended understanding of the liquid–solid contact electrification, which is significant in both fundamental and applied science of liquid–solid TENG.

Sustainability issues have gained growing awareness in recent years. Governments play an important role in environment and resources problems since they can affect enterprises’ production activities by enacting policies and regulations. To promote green production in the long term associated with the consideration of financial intervention of governments, we establish a three-population model of suppliers, manufacturers and governments based on evolutionary game theory, and analyze the evolutionary stable strategies (ESS) of their unilateral and joint behaviors. Further, system dynamics (SD) is applied to empirical analysis for exploring the dynamic interaction of the populations’ strategy, and the key factors affecting ESS are also discussed in detail. The results show that: (1) the proportion of green suppliers and manufacturers in their groups determines whether the government implements regulation; (2) any party of the supplier and manufacturer that adopts green strategy could promote green behavior of the other; (3) the government is advised to supervise and implement reward and punishment mechanism under the low proportion of green supply chain; (4) government regulation could promote the corporations to adopt green behavior and should preferentially implements the mechanism on manufacturers. The results provide insights into the policy-making of governments and enterprises management on sustainable development.

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Various indicators are used to qualify the performance of intermodal transportation systems. Some of these are found in public documents, usually providing global measures such as total flow volumes, profits, and share values. While of great interest, such measures are not sufficient to support a fine analysis of different operation strategies, commercial policies, and planning methods. Additional measures are used in the scientific literature to address these issues. Our first goal is to review the performance indicators found in scientific literature and to qualify them with respect to tactical planning of intermodal barge transportation systems. We extend this analysis to include revenue management policies, a topic generally neglected in freight transportation. We also discuss procedures to generate problem instances that provide the means to analyze planning methods and system behavior based on these performance indicators.