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Multifunctional sensing systems play important roles in a variety of applications, incluing health surveillance, intelligent prothetics, human-machine/ambinece interfaces, and many others. The richness of the signal and the decoupling among multiple parameters are essential for simultaneous, multimodal measurements. However, current multifunctional sensing fails to decouple interferences from various signals. Here, we propose a double-sided wearable system that both enables multifunctional sensing and avoids the interferences among multiple parameters. Specifically, the sensitivities of system modules to strain are controlled through customizing the pattern and morphology of sensing electrodes as well as the modification of active materials. Compensation of temperature drift and selection of sensing mechanisms ensure the thermal stability of the system. The encapsulation of modules resists the interferences of proximity, normal pressure, and gas molecules at the same time. A double-sided partition layout with serpentine interconnections reduces the effect of motion artifacts and ensures simultaneous operation of electrochemical-sensing modules. Cooperation among decoupled modules acts as the bridge between the perception of ambience changes and the timely feedback of the human body. In addition, to sense the signal at the interface, modules for energy harvesting and storage are also integrated into the system to broaden its application scenarios.

In the age of “Internet+”, many Internet service platforms (ISPs) in China have been widely introduced to the closed-loop supply chain (CLSC). To further study the role of the Internet service platform, this paper considers a CLSC composed of a manufacturer, a retailer and an Internet service platform who invests in research and development (R&D), advertising and Big Data marketing, and develops the goodwill dynamic model based on the differential game theory. The construction of a goodwill dynamic model has two purposes, namely, to increase sales and the return rate. The optimal decisions for 3 players under two different cooperative scenarios are obtained, namely, the retailer payment scenario (scenario D) and the manufacturer cost-sharing scenario (scenario S). The supply chain members gain more profit or achieve a higher level of goodwill for products under certain conditions, i.e., a high residual value from remanufacturing, a high sharing rate of residual value from the retailer's recycled products, and a low recycling cost. Interestingly, the wholesale price increases with the residual value of recycled products when goodwill effectiveness is low, while the price declines when goodwill effectiveness is high. After comparing two cooperative scenarios, the result shows that an Internet service platform will invest more in Big Data marketing under the manufacturer cost-sharing scenario, and cooperation between the manufacturer and the Internet service platform can help improve the goodwill of enterprises or products. Moreover, the manufacturer cost-sharing scenario is payoff-Pareto-improving in most cases through the coordination of a cost-sharing rate, and the effectiveness of Big Data marketing exerts a positive effect on goodwill and the development of the industry. In addition, the retailer has “free rider” tendencies in the manufacturer cost-sharing scenario. The results encourage more enterprises to enhance the value of goodwill through cooperation with Internet service platforms because Internet service platforms conveniently utilize Big Data marketing to increase the sales of products and the collecting rate of used products, which in turn helps environmental sustainability.

Microelectrode array (MEA) is a powerful tool for recording electrophysiological signals and studying the electrophysiological features of nerve, retina, and cardiomyocytes. Stretchable electrodes can form conformal contact with dynamic biological tissues/organs (e.g. heart) to enhance the coupling efficiency in electrophysiological measurements. However, MEAs based on conventional materials require serpentine interconnections to enable stretchability. A large number of serpentine interconnects take up spaces and hinder the improvement of spatial resolution. Here, we introduce a multilayer design strategy that yields a stretchable MEA with spatial density of 7.3 sites mm−2 and biaxial stretchability of 30%. The serpentine interconnects of each layer overlap vertically to reduce the area of the wires used for connection. In vitro validation in phosphate buffered saline and ex vivo test on perfused mouse heart show a 100% yield rate of the multilayer stretchable MEA, with capabilities in spatiotemporal mapping of electrophysiological signals at high spatial resolution.

Aiming at improving the precision and decreasing roughness of micro-manufacturing, this work proposes a new method that combines non-uniform graphic compensation for template preparation and demolding with viscous fluid composed of mixtures of two types of polydimethylsiloxane (PDMS), Sylgard 184 and SE 1700. Notably, this method can widely apply to a bounty of micro-manufacturing methods, such as laser direct writing (LDW), 3D printing, and lithography. This paper exploits LDW to fabricate smooth convex microdome array (MA) on PDMS, and demonstrates the applications of such microstructures in electronics and optics. Specifically, the multifunctional microstructure can serve as a pressure sensor with high sensitivity and broad range, a strain senor for biaxial strain sensing and an anti-reflection film to improve photoelectric conversion efficiency of solar cells.

The advent of functional materials offers tremendous potential in a broad variety of areas such as electronics, robotics, and energy devices. Magnetic materials are an attractive candidate that enable multifunctional devices with capabilities in both sensing and actuation. However, current magnetic devices, especially those with complex motion modalities, rely on permanently magnetized materials with complicated, non-uniform magnetization profiles. Here, based on magnetic materials with temporary-magnetization, a mechanically guided assembly process successfully converts laser-patterned 2D magnetic materials into judiciously engineered 3D structures, with dimensions and geometries ranging from mesoscale 3D filaments, to arrayed centimeter-scale 3D membranes. With tailorable mechanical properties and highly adjustable geometries, 3D soft structures can exhibit various tethered locomotions under the precise control of magnetic fields, including local deformation, unidirectional tilting, and omnidirectional rotation, and can serve as dynamic surfaces for further integration with other functional materials or devices. Examples demonstrated here focus on energy-harvesting systems, including 3D piezoelectric devices for noncontact conversion of mechanical energy and active motion sensing, as well as 3D solar tracking systems. The design strategy and resulting magnetic-controlled 3D soft structures hold great promise not only for enhanced energy harvesting, but also for multimodal sensing, robotic interfaces, and biomedical devices.

In this paper, we report a magnetic and conductive textile made from a mixture of NdFeB microparticles, multi-walled carbon nanotubes, and polydimethylsiloxane. The textile can (i) shield 99.8% of electromagnetic signals ranging from 30 MHz to 3 GHz, thereby protecting people from damage caused by the electromagnetic radiation, (ii) be hydrophobic and fire retardant, making it a possible choice for raincoat and fire protection clothing, and (iii) convert mechanical energy into electricity through both electromagnetic induction and triboelectrification. The textile creates many opportunities in the fields of multifunctional protective equipment and energy harvesting.

In the “Internet+” era, involving third-party Internet recycling platforms (IRPs) has revolutionized the operation models of closed-loop supply chains (CLSCs) in China. This study explores the impact of technological innovation, Big Data marketing and overconfidence on supply chain member decision-making. We propose a two-stage remanufacturing CLSC dynamic model consisting of a manufacturer, an IRP, and a supplier based on differential game theory. By comparing the optimal decisions of each member in three scenarios, we find that the IRP’s overconfident behavior is beneficial to both the manufacturer and the IRP but will damage the supplier's profit. Although a suitable cost-sharing ratio can enable the manufacturer and IRP to achieve a “win–win” situation, an excessive level of confidence will inhibit the incentives of the cost-sharing strategy, negatively affecting the manufacturer's interests. Interestingly, a cost-sharing contract will become inefficient under certain conditions, i.e., highly efficient level of technological innovation, highly efficient Big Data marketing, and a high level of overconfidence, negatively affecting the manufacturer’s interests. Additionally, technological innovation efficiency and marketing efficiency will have different effects on the IRP's recycling price. A cost-sharing contract and the IRP’s overconfidence will prompt the IRP to exert more efforts on technological innovation and Big Data marketing and to significantly reduce the manufacturing costs and recycling costs for all members. Notably, although the IRP’s overconfidence and cost-sharing strategies may damage the supplier’s profit, the total profit of the CLSC increases.

Graphene-based phosphorus-doped carbon (GPC) is prepared through a facile and scalable thermal annealing method by triphenylphosphine and graphite oxide as precursor. The P atoms are successfully doped into few layer graphene with two forms of P–O and P–C bands. The GPC used as anode material for Na-ion batteries delivers a high charge capacity 284.8 mAh g−1 at a current density of 50 mA g−1 after 60 cycles. Superior cycling performance is also shown at high charge−discharge rate: a stable charge capacity 145.6 mAh g−1 can be achieved at the current density of 500 mA g−1 after 600 cycles. The result demonstrates that the GPC electrode exhibits good electrochemical performance (higher reversible charge capacity, super rate capability, and long-term cycling stability). The excellent electrochemical performance originated from the large interlayer distance, large amount of defects, vacancies, and active site caused by P atoms doping. The relationship of P atoms doping amount with the Na storage properties is also discussed. This superior sodium storage performance of GPC makes it as a promising alternative anode material for sodium-ion batteries.