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The conductive polymer poly-3,4-ethylenedioxythiophene (PEDOT), recognized for its superior electrical conductivity and biocompatibility, has become an attractive material for developing wearable technologies and bioelectronics. Nevertheless, the complexities associated with PEDOT’s patterning synthesis on diverse substrates persist despite recent technological progress. In this study, we introduce a novel deep eutectic solvent (DES)-induced vapor phase polymerization technique, facilitating nonrestrictive patterning polymerization of PEDOT across diverse substrates. By controlling the quantity of DES adsorbed per unit area on the substrates, PEDOT can be effectively patternized on cellulose, wood, plastic, glass, and even hydrogels. The resultant patterned PEDOT exhibits numerous benefits, such as an impressive electronic conductivity of 282 S·m−1, a high specific surface area of 5.29 m2·g−1, and an extensive electrochemical stability range from −1.4 to 2.4 V in a phosphate-buffered saline. To underscore the practicality and diverse applications of this DES-induced approach, we present multiple examples emphasizing its integration into self-supporting flexible electrodes, neuroelectrode interfaces, and precision circuit repair methodologies.

In order to resolve the global crisis of fossil energy shortage and climate warming, the development of efficient energy storage devices is a significant topic at present. Supercapacitors as the novel type of energy storage devices have the unique advantages, including the fast charging/discharging behaviors, high-energy/power density, and stable cycling performance. Compared with traditional supercapacitors, flexible supercapacitors are environmentally friendly, light weight, small size and high safety. Therefore, flexible supercapacitors have a wide application prospect in emerging electronic devices. Due to its flexibility, biocompatibility, and structure designability, cellulose and its gel materials are gradually used as electrodes, separators and electrolytes in flexible supercapacitors. Several construction processes at molecular scale for high-performance cellulose gels are summarized. Meanwhile, this review covers the recent progress of developing the flexible supercapacitors and all-in-one supercapacitors based on cellulose functional gels. We finally discussed the potential challenges and opportunities for cellulose and its derived materials in new-style flexible supercapacitors and other electronic devices.

Abstract Structure design provides an effective solution to develop advanced soft materials with desirable mechanical properties. However, creating multiscale structures in ionogels to obtain strong mechanical properties is challenging. Here, an in situ integration strategy for producing a multiscale‐structured ionogel (M‐gel) via ionothermal‐stimulated silk fiber splitting and moderate molecularization in the cellulose‐ions matrix is reported. The produced M‐gel shows a multiscale structural superiority comprised of microfibers, nanofibrils, and supramolecular networks. When this strategy is used to construct a hexactinellid inspired M‐gel, the resultant biomimetic M‐gel shows excellent mechanical properties including elastic modulus of 31.5 MPa, fracture strength of 6.52 MPa, toughness reaching 1540 kJ m−3, and instantaneous impact resistance of 3.07 kJ m−1, which are comparable to those of most previously reported polymeric gels and even hardwood. This strategy is generalizable to other biopolymers, offering a promising in situ design method for biological ionogels that can be expanded to more demanding load‐bearing materials requiring greater impact resistance.

Abstract Poly (3,4‐ethylene dioxythiophene) (PEDOT) is an electrically conductive polymer that shows various promising applications in flexible electronics. However, previous studies have mostly focused on enhancing the conductivity, while ignoring the design and development of porous PEDOT materials. Herein, we report a novel and sustainable strategy of utilizing a deep eutectic solvent of ferric chloride hexahydrate/acetamide to guide the interface‐controlled polymerization of PEDOT at room temperature. The obtained PEDOT material has its unique features of high porosity of 70.61%, high specific surface area of >58 m2/g, and ideal electrical conductivity of 6500 S/m, resulting in a wide voltage window of up to 1.2 V. Notably, this porous PEDOT can be easily formulated into printable electronic ink with controllable rheological properties, process ability, and recyclability, exhibiting the outstanding energy storage behavior in wearable electronics. This study reports an effective, green approach for the development of porous PEDOT materials and printable flexible devices.

A lateral motion control scheme for a distributed drive electric vehicle is presented in this paper, which takes into account both in-car network and movement-parameter uncertainty in a synthetic manner. Distributed drive vehicles have obvious advantages in terms of safety and comfort at high speeds due to the well-known E/E architecture, which includes an in-vehicle network, advanced vehicle motion control, and Advanced Driver Assistance System (ADAS) technologies. This is a fundamentally cyber-physical system. However, on the other hand, the application/insertion of in-vehicle network and the dynamic of wide-range varying speeds introduce additional system uncertainties, such as time-varying network induced delays and inevitable system perturbation, making controller design a difficult problem and even making the system unstable. This paper develops a cyber-physical control scheme and under which a two-process perturbation analysis is proposed to illustrate the system uncertainties. A hierarchical control strategy is also devised, with an upper-level gain-scheduling controller dealing with speed perturbation uncertainties and a lower-level $H_{\mathrm {\infty }}$ -LQR controller dealing with in-vehicle network uncertainty. Using real-time hardware in loop testing, the suggested control technique was found to be effective in dealing with both in-vehicle network and system perturbation problems while also ensuring reliable vehicle stability in all three scenarios.

Tritium waste deposition in air-unsaturated groundwater zones poses great challenges to optimal water allocation. This paper reviews the research progress of air-unsaturated-groundwater interaction. Traditional interaction studies typically model the fate and migration of pollutants in different regions. This can lead to biased results and simulation errors. The development of air-unsaturated-ground integrated modeling will be a breakthrough and a hotspot in tritium management. In this paper, the fate and migration of tritium leakage is further studied using the existing extended Environment Multimedia Modeling System (EEMMS). Moreover, to better understand its distribution in three zones, using tritium as a typical pollutant, it is necessary to consider its characteristics in different zones, especially its migration from unsaturated zones to groundwater and air zones. The result shows that the tritiated water vapor transfer in unsaturated groundwater areas decreases and part of the tritiated water vapor transfers to atmospheric areas as tritiated gas vapor. Compared with the analytical test accuracy (5 pCi mL−1), the accuracy of the tritium modeling using the finite element method can reach the minimum concentration limit of 0 pCi mL−1. The study of its distribution in air-unsaturated-groundwater zones can provide reference for other similar tritium management or NAPLs distribution across multimedia area.

Electronic skin (e-skin), a new generation of flexible electronics, has drawn interest in soft robotics, artificial intelligence, and biomedical devices. However, most existing e-skins involve complex preparation procedures and are characterized by single-sensing capability and insufficient scalability. Here, we report on a one-step strategy in which a thermionic source is used for the in situ molecularization of bacterial cellulose polymeric fibers into molecular chains, controllably constructing an ionogel with a scalable mode for e-skin. The synergistic effect of a molecular-scale hydrogen bond interweaving network and a nanoscale fiber skeleton confers a robust tensile strength (up to 7.8 MPa) and high ionic conductivity (up to 62.58 mS/cm) on the as-developed ionogel. Inspired by the tongue to engineer the perceptual patterns in this ionogel, we present a smart e-skin with the perfect combination of excellent ion transport and discriminability, showing six stimulating responses to pressure, touch, temperature, humidity, magnetic force, and even astringency. This study proposes a simple, efficient, controllable, and sustainable approach toward a low-carbon, versatile, and scalable e-skin design and structure–performance development.

This paper presents a nonlinear model predictive control with terminal cost (NMPC–WTC) algorithm and its open/closed-loop system analysis and simulation validation for accurate and stable path tracking of autonomous vehicles. The path tracking issue is formulated as an optimal control problem. In order to improve the squeezing phenomenon of traditional NMPC, a discrete-time nonlinear model predictive controller with terminal cost is then designed, in which the state error of last step is augmented. The cost function of NMPC–WTC consists of two parts: (1) the traditional NMPC cost function responding to tracking errors and controller output, and (2) the augmented terminal cost. The algorithm was implemented on CasADi numerical optimization framework, which is free, open-source and developed for nonlinear optimization. The open-loop and closed-loop simulation results are then presented to demonstrate the improved performance in tracking accuracy and stability compared to traditional model predictive controller.

Injection drug users bear the burden of HIV in Vietnam and are a focus of national treatment programmes. To date, determinants of successful therapy in this population are unknown. Substance use and clinical correlates of viral suppression were studied in 100 HIV-1-infected drug users receiving antiretroviral therapy (ART) for at least six months in Hanoi, Vietnam. The mean age of the cohort was 29.9 + 4.9 years; all were men. A majority of patients (73%) achieved viral suppression (HIV-RNA <1000 copies/mL). Correlates of viral suppression include self-reported > or = 95% adherence (P < 0.01) and current use of trimethoprim/sulphamethoxazole (P < 0.01); current or ever diagnosed with tuberculosis was associated with viral non-suppression (P = 0.006). Tobacco use was prevalent (84%), and surprisingly 48% of patients reported active drug use; neither was associated with viral non-suppression. This is the first study to document successful ART treatment in a population of Vietnamese drug users; rates of viral suppression are comparable to other international populations. The 28% of patients without HIV-1 suppression highlight the need for adherence promotion, risk reduction programmes, and population-based surveillance strategies for assessing the emergence of HIV drug resistance in settings where access to viral load and drug resistance testing is limited. [ABSTRACT FROM AUTHOR]

Abstract The separator is of great importance for regulating ion transmission, maintaining electrode stability, and device safety in lithium‐ion batteries. Despite their many advantages, glass microfiber separators have shortcomings that often give rise to poor cycle performance and fatal short‐circuit risk when used in flexible batteries. Here, we propose the use of a scalable non‐Newtonian fluidic cellulose permeation‐diffusion strategy to develop a cellulose/glass microfiber composite film with an hourglass‐gradient structure. Due to the unique gradient morphology resulting from the presence of cellulose macromolecules, the as‐prepared composite film showed an improved surface mass density, adjustable pore structure, controllable ion transport, ideal mechanical flexibility, and robustness. When used as the separator in an assembled lithium‐ion battery, the composite film exhibited rapid ion diffusion and Li dendrite inhibition, which endowed the battery with excellent cycle stability (specific capacity of 108.5 mAh g−1 after 1000 cycles) and good rate performance. This composite film shows great potential application in flexible lithium‐ion batteries including but not limited to pouch cells.

Considering the battery-failure-induced catastrophic events reported frequently, the early fault warning of batteries is essential to the safety of electric vehicles (EVs). Motivated by this, a novel data-driven method for early-stage battery-fault warning is proposed in this paper by the fusion of the short-text mining and the grey correlation. In particular, the short-text mining approach is exploited to identify the fault information recorded in the maintenance and service documents and further to analyze the categories of battery faults in EVs statistically. The grey correlation algorithm is employed to build the relevance between the vehicle states and typical battery faults, which contributes to extracting the key features of corresponding failures. A key fault-prediction model of electric buses based on big data is then established on the key feature variables. Different selections of kernel functions and hyperparameters are scrutinized to optimize the performance of warning. The proposed method is validated with real-world data acquired from electric buses in operation. Results suggest that the constructed prediction model can effectively predict the faults and carry out the desired early fault warning.

This paper deals with the negative effects of the in-vehicle network on the integrated anti-slip control (ASC) and direct yaw-moment control (DYC) of all-wheel-independent-drive electric vehicles (AWID-EVs). In the integrated control design of the modern AWID-EVs, increasing control components, e.g., sensors, controllers, and actuators, are usually connected via an in-vehicle network, such as a controller area network (CAN), rather than the traditional point-to-point communication. However, the application of CAN would also bring about unexpected problems, e.g., signal asynchrony, multiple-package transmission, and signal delay, which may degrade the control performance and even destroy the stability of the system. This paper presents a co-design methodology to deal with all these challenges caused by CAN and guarantees a satisfactory vehicle dynamics performance. First, a hierarchical structure is designed for the integrated ASC and DYC control of AWID-EVs over CAN, and an active torque distribution strategy based on a well-known maximum transmissible torque estimation approach is adopted. Then, a scheduling-based communication idea is introduced to deal with all these problems caused by CAN. Third, a Lyapunov-based pole assignment theory is applied to estimate the parameter values in the scheduling design and to guarantee the satisfactory dynamic performance of the control system. A generalized linear quadratic regulator controller is designed for the system synthesis to ensure the tracking control of the vehicle. Finally, simulations and preliminary hardware-in-loop tests indicate that the proposed co-design methodology can deal with the negative effects of the in-vehicle network and ensure reliable vehicle dynamics performance.