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Fiber agglomeration and poor interfacial combination with the matrix restrict the performance of composites. Herein, soybean meal-based adhesives were fabricated via the addition of dialdehyde cellulose (DAC) obtained from waste paper dissolved in an alkali–urea system and oxidized with sodium periodate. Due to the dissolution by the alkali–urea system, DAC dispersed well in the solution and did not aggregate in the adhesive matrix. Because of the oxidation treatment, DAC was crosslinked with the adhesive matrix via a Schiff base reaction. Meanwhile, hydrogen bonds were formed at the interface between the DAC and the adhesive matrix. Plywood with the SM/DAC/PTGE adhesive reached its highest wet bonding strength of 1.27 MPa (4 wt% DAC addition), a 95% increase compared to that with the unmodified SM/PTGE adhesive. Fine DAC-to-SM interfacial bonding and a dense crosslinking network were constructed in the SM/DAC/PTGE adhesive systems. The cycle of reuse for the alkali–urea system in the experiments demonstrated that the preparation method of the cellulose solution was scalable and sustainable.Graphic abstract

Compared to traditional organic liquid electrolytes, which often present leakage, flammability, and chemical stability problems, solid polymer electrolytes (SPEs) are widely regarded as one of the most promising candidates for the development of safer lithium‐ion batteries. Vitrimers are a new class of polymer materials consisting of dynamic covalent networks that can change their topology by thermally activated bond‐exchange reactions. Herein, the recyclable and self‐healing solid polymer electrolytes (SPEs) with a soy protein isolate (SPI)‐based imine bond dynamic network are reported. This malleable covalent cross‐linked network polymer can be reshaped and recycled at high temperature (100 °C) or only with water at ambient temperature (25 °C), which may realize the green processing of energy materials. The introduction of bis(trifluoromethane) sulfonimide lithium (LiTFSI) significantly reinforces the conductivity of the dynamic network to a maximum of 3.3 × 10−4 S cm‐1. This simple and applicable method establishes new principles for designing scalable and flexible strategies for fabricating polymer electrolytes. The recyclable and self‐healing solid polymer electrolytes (SPEs) with a soy protein isolate (SPI)‐based imine bond dynamic network display favorable mechanical strength (77.4 MPa), high ionic conductivity (3.3 × 10−4 S cm−1). Thus, the SPEs based on the imine bond dynamic network of SPI is a promising platform for recyclable and repairable electrolytes.

In the realm of sensorless control for a permanent magnet synchronous motor (PMSM), the flux observer algorithm is widely recognized. However, the estimation accuracy of rotor position is adversely impacted by the interference from DC bias and high-order harmonics. To address these issues, an advanced flux observation method, second-order generalized integrator flux observer extend (SOGIFO-X), is introduced in this paper. The study begins with a theoretical analysis to establish the relationship between flux observation error and rotor position error. The SOGIFO-X method, developed in this study, is compared with traditional methods such as the Low Pass Filter (LPF) and second-order generalized integrator flux observer (SOGIFO), employing mathematical rigor and Bode plot analysis. The emphasis is on the methodology and the general performance improvements SOGIFO-X offers over conventional methods. Simulations and experiments were conducted to assess the impact of SOGIFO-X on the steady-state and dynamic performances of sensorless control. Findings indicate that SOGIFO-X demonstrates significant enhancements in terms of reducing the reduced flux observation error, contributing to the advancement of position estimation accuracy and sensorless motor control technology.

The performance of the extended state observer (ESO) in an Active Disturbance Rejection Control (ADRC) is limited by the operational load in stepper motor control, which has high real-time requirements and may cause delays. Additionally, the complexity of parameter tuning, especially in high-order systems, further limits the ESO’s performance. This paper proposes a composite ADRC (LTDRO-ADRC) based on a load torque dimensionality reduction observer (LTDRO). Firstly, the LTDRO is designed to estimate abrupt load disturbances that are difficult to compensate for using the ESO. Secondly, the transfer function under the double-closed loop is deduced. Additionally, the LTDRO uses a magnetic encoder to gather the system state and calculate the load torque. It then outputs a compensating current feedforward to the current loop input. This method reduces the delay and complexity of the ESO, improving the response speed of the ADRC speed ring and the overall response of the system to load changes. Simulation and experimental results demonstrate that it significantly enhances dynamic control performance and steady-state errors. LTDRO-ADRC can stabilize the speed again within 49 ms and 17 ms, respectively, in the face of sudden load increase and sudden load removal. At the same time, in terms of steady-state error, compared with ADRC and CADRC, they have increased by 94% and 88%, respectively. In terms of zero-speed starting motors, the response speed is increased by 58% compared to a traditional ADRC.

Highlights The advantages of biomass materials for electromagnetic interference (EMI) shielding are analyzed, the mechanism of EMI shielding is summarized, and the factors affecting EMI shielding are analyzed systematically. Various biomass materials (wood, bamboo, lignin, cellulose) were modified to obtain unique structures and improve EMI shielding performance. The problems encountered in the application of biomass materials for EMI shielding are summarized, and the potential development and application in the future are prospected. Research efforts on electromagnetic interference (EMI) shielding materials have begun to converge on green and sustainable biomass materials. These materials offer numerous advantages such as being lightweight, porous, and hierarchical. Due to their porous nature, interfacial compatibility, and electrical conductivity, biomass materials hold significant potential as EMI shielding materials. Despite concerted efforts on the EMI shielding of biomass materials have been reported, this research area is still relatively new compared to traditional EMI shielding materials. In particular, a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment, preparation process, and micro-control would be valuable. The preparation methods and characteristics of wood, bamboo, cellulose and lignin in EMI shielding field are critically discussed in this paper, and similar biomass EMI materials are summarized and analyzed. The composite methods and fillers of various biomass materials were reviewed. this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.

Demethylation technique has been used to enhance lignin reactivity for preparation of phenolic resins. However, the demethylation efficiency and the demethylated lignin (DL) reactivity were still unsatisfactory. To improve the demethylation efficiency, alkali lignin was demethylated under different mild conditions using sodium sulfite as a catalyst. Lignin and DL were characterized by 1H-NMR (nuclear magnetic resonance) and Fourier transform infrared (FT-IR) spectroscopy to determine the demethylation mechanism. With the demethylation of lignin, the methoxyl group content decreased from 1.93 m mol/g to 1.09 m mol/g, and the phenolic hydroxyl group content increased from 0.56 m mol/g to 0.82 m mol/g. These results revealed that methoxyl groups were attacked by SO32−, and some methoxyl groups were converted to phenolic hydroxyl groups by a nucleophilic substitution reaction, generating DL with high reactivity. The chemical properties of lignin-based phenolic resins were studied by 13C-NMR and FT-IR spectroscopy, and their physical properties were also investigated. The results indicated that lignin-based phenolic resins exhibited faster curing rate and shorter gel time. In addition, the bonding strength increased from 0.92 MPa to 1.07 MPa, and the formaldehyde emission decreased from 0.58 mg/L to 0.22 mg/L after lignin demethylated at the optimum condition.

Interfacial solar steam generation (ISSG) is the main method to get fresh water from seawater or wastewater. The balance between evaporation rate and salt resistance is still a major challenge for ISSG. Herein, a wood aerogel island solar evaporator (WAISE) with tunable surface structure and wettability by synthesizing poly(n‐isopropylacrylamide)‐modified multi‐walled carbon nanotube photothermal layers. Compared to dense surface structure evaporators, interfacial moisture transport, thermal localization, and surface water vapor diffusion of WAISE are greatly promoted, and the evaporation rate of WAISE increased by 87.64%. WAISE allows for record performance of 200 h continuous operation in 20% NaCl solution without salt accumulation. In addition, the photo‐thermal‐electric device is developed based on WAISE with continuous water purification, power generation, and irrigation functions. This work provides a new direction for the development of multifunctional water purification systems. In this paper, a wood aerogel island solar evaporator (WAISE) with tunable surface structure and wettability is prepared by synthesizing a poly(n‐isopropylacrylamide)‐modified multi‐walled carbon nanotubes photothermal material. WAISE has effectively balanced the contradiction between evaporation rate and salt tolerance, so that this work provides a new research idea for the application of a wood evaporator in seawater desalination.

Interfacial solar evaporation technology is considered one of the most promising strategies for alleviating the scarcity of freshwater resources. However, solar-driven evaporation technology cannot eliminate the pollutants in the residual wastewater. To solve this problem, we have prepared a two-in-one solar-driven evaporation/photocatalysis system by decorating MoS 2 /covalent organic framework (COF) heterojunctions on wood (MoS 2 /COF-wood). Thanks to the unique porous structure of wood, it provides a strong guarantee for water transport and vapor release during the evaporation process. The introduction of MoS 2 and COFs can promote the breaking of hydrogen bonds between water molecules, which leads to a significant decrease in the enthalpy of evaporation, achieving a water evaporation rate as high as 2.17 kg m −2 h −1 under 1 sun irradiation. Meanwhile, the resulting MoS 2 /COF-wood exhibits good salt resistance and reusability. In addition, the heterojunctions formed between COFs and MoS 2 can effectively inhibit charge carrier complexation and improve the photocatalytic degradation ability of pollutants (over 99%). This study highlights the construction strategy of bifunctional wood-based materials for freshwater production and wastewater remediation.

Soy meal-based wood adhesive has received much interest for its environmentally friendly properties, as it is thought to provide an effective alternative to conventional formaldehyde-based wood adhesives. However, the abundant hydrophilic groups and weak internal structure result in poor water resistance and low bonding strength of soy meal-based wood adhesives. In this study, bio-based carboxymethylated wood fibers (CMWFs) were used to develop a high-performance soy meal-based adhesive. Wood fibers (WFs) were pre-treated via carboxymethylation to endow WFs with abundant carboxyl groups and facilitate their dispersion in soy protein matrix. CMWFs containing abundant carboxyl groups served as a multiple “crosslinking core” and effectively cross-linked with soy protein side-chain, resulting in the construction of a stable adhesive system. The modified soy meal-based adhesive exhibited excellent bonding strength and water resistance. In particular, tension tests indicated that the water-resistant bonding strength of the adhesive modified with CMWFs reached 1.69 MPa, which was 160% higher compared with the unmodified adhesive; the wood failure percentage of the plywood bonded by CMWF-modified soy meal-based adhesive was as high as 100%. Moisture uptake and residual rate tests indicated that high water resistance of the adhesive was achieved. This design provides a facile and sustainable strategy for developing high-performance soy meal-based adhesives.Graphic abstract

Using the precision trigonometric elevation instead of the precision levelling to build a CPⅢ elevation control network will greatly increase the speed of CPⅢ control network construction. However, the accuracy of CPIII precision trigonometric elevation control network is still difficult to reach the level of CPⅢ precision levelling network. Based on the existing parameter method, this paper introduces some precision levelling for joint adjustment, and uses Helmert’s variance estimation method to perform strict weight determination. Our experiments show that when the number of precision levelling participating in the joint adjustment exceeds 1/3 of the total number of CPⅢ precision levelling network observations, the accuracy of the CPIII precision trigonometric elevation control network can be effectively improved.