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In recent years, flexible sensors constructed mainly from hydrogels have received increasing attention. However, conventional hydrogels need to be prepared by high-temperature or radiation-induced polymerization reactions, which limits their practical applications due to their suboptimal electrical conductivity and weak mechanical properties. In this paper, using sodium lignosulfonate as the raw material, a dynamic catechol-quinone redox system formed by lignin‑zinc ions was constructed to initiate rapid free radical polymerization of acrylamide (AM) monomer at room temperature. In addition, Deep eutectic solvent (DES) can form a strong hydrogen bonding network within the molecules and between the molecules of the hydrogel, resulting in a hydrogel with good tensile properties (hydrogel elongation at break of 727.19 %, breaking strength of 84.09 kPa), and provides the hydrogel with high electrical conductivity, anti-dehydration, anti-freezing, and anti-bacterial properties. Meanwhile, the addition of lignin also improved the adhesion and UV resistance of the hydrogel. This hydrogel assembled into a flexible sensor can sense various small and large amplitude movements such as nodding, smiling, frowning, etc., and has a wide range of applications in flexible sensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Developing a high-performance activator is crucial for the practical application of peroxymonosulfate-based advanced oxidation processes (PMS-AOPs). High-entropy oxides (HEOs) have attracted increasing attention due to their stable crystal structure, flexible composition and unique functionality. However, research into the mechanisms by which HEOs function as PMS activators for degrading organic pollutants remains insufficient, and the relationship between entropy and the catalytic performance of HEOs has yet to be clarified. In this study, we synthesized NiMgZnCuCoO x with different levels of entropy as PMS activators for acetaminophen (APAP) degradation, and observed a significant effect for entropy on the catalytic performance. Sulfate radicals (SO 4 • ‒ ) were identified as the primary reactive oxygen species (ROS), while hydroxyl radicals (•OH) and singlet oxygen ( 1 O 2 ) act as secondary ROS during APAP degradation. Both the Co 2+ contents and the oxygen vacancy concentration in NiMgZnCuCoO x are found to increase with the entropy. An increase in the Co 2+ sites leads to more activation sites for PMS activation, while excessive oxygen vacancies consume PMS, producing weak oxidation species, and affect the electron-donating ability of Co 2+ . Consequently, the NiMgZnCuCoO x with middle level of entropy exhibits the optimal performance with APAP degradation rate and mineralization rate reaching 100% and 74.22%, respectively. Furthermore, the degradation intermediates and their toxicities were assessed through liquid chromatography-mass spectrometry and quantitative structure-activity relationship analysis. This work is expected to provide critical insight into the impact of the HEOs entropy on the PMS activation and guide the rational design of highly efficient peroxymonosulfate activators for environmental applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Converting lignin into specific aromatic chemicals for utilization through depolymerization of lignin is an effective way to achieve high-value applications. There are many depolymerization methods that can do this, but there are problems such as harsh reaction conditions, low depolymerization efficiency and uncontrollable target products that need to be solved. This study reports a novel system for the oxidative depolymerization of alkali lignin using Fe- and Mn- modified TS-1 as a catalyst to assist in the highly selective production of vanillin. We also proposed a possible reaction pathway for the oxidative depolymerization of alkali lignin to produce vanillin catalyzed by Fe-Mn/TS-1 catalyst. The catalytic effects of TS-1, Fe/TS-1, and Fe-Mn/TS-1 catalysts on the oxidative depolymerization of lignin to produce phenolic monomers and vanillin were investigated. The results show that the modified catalysts can effectively improve the efficiency of linkage bond breaking in lignin, especially the β-O-4 bond, in which the inter-band transitions of Fe and Mn play an important role. The synergistic effect of the bimetallic-loaded catalyst (Fe-Mn/TS-1) could catalyze the oxidative depolymerization of lignin more efficiently than the monometallic-loaded catalyst (Fe/TS-1). This lignin oxidative depolymerization system produced 40.59 wt% bio-oil including 12.24 wt% phenolic monomers and 16.17 wt% re-lignin after the addition of Fe-Mn/TS-1 catalyst, owning the highest phenolic monomer yield. Surprisingly, this lignin oxidative depolymerization system exhibited high yield for vanillin (8.36 wt%) production. These results demonstrated that the Fe-Mn/TS-1 catalytic system has potential to produce vanillin from lignin under mild conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The rapid development of the industry has led to the destruction of the earth's ozone layer, resulting in an increasingly serious problem of excessive ultraviolet radiation. Exploring effective measures to address these problems has become a hot topic. Lignin shows promise in the design and preparation of anti-ultraviolet products due to its inherent properties. However, it is important to investigate way to enhance the reactivity of lignin and determine its application form in related products. In this study, phenolic reactions with tea polyphenols were conducted through acid-catalyzed conversion, utilizing organic solvent lignin as the primary material. The phenolic hydroxyl content of the original lignin increased significantly by 218.8 %, resulting in notable improvements in UV resistance and oxidation resistance for phenolic lignin. Additionally, micro-nanocapsule emulsions were formed using phenolic lignin particles as surfactants through ultrasonic cavitation with small-molecule sunscreens. A bio-based sunscreen was prepared with phenolated lignin micro-nanocapsules as the active ingredient, achieving an SPF 100.2 and demonstrating excellent stability. The sunscreen also exhibited strong antioxidant properties and impermeability, ensuring user safety. This research offers a current solution for improving the application of lignin in sunscreens while also broadening the potential uses of plant-based materials in advanced functional products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Silylated cellulose has been successfully synthesized using TEMPO-oxidized nanocellulose (TEMPO-NC) from oil palm empty fruit bunch and 3-aminopropyltriethoxysilane (APS) in an ethanol/water medium at a low curing temperature of 40 °C as compared to those reported in the literature of above 100 °C. Confirmation of the grafting process can be seen from the new FTIR peaks at 810 cm -1 and 749 cm -1 which are attributed to the SiC stretching and SiC, and new 13 C NMR signals at 10.3, 21.7 and 42.7 ppm which are assigned to C7, C8, and C9 of the silylated TEMPO-NC. The decrease in the intensities of the cellulose peaks of C2, C3, C6 and C6' in the 13 C NMR indicates that silylation not only occurs on the hydroxyls, but more importantly on the TEMPO-NC carboxylic moiety of C6', which is postulated as being the primary factor for this successful modification. This is further corroborated by the emergence of three signals at 43, 61, and 69 ppm in the 29 Si NMR spectrum which corresponds to Si(OSi)(OR) 2 R', Si(OSi) 2 (OR)R', and Si(OSi) 3 R' units respectively. Additional evidence is provided by the EDX which shows an increase in Si weight percent of 1.94 after reaction. This silylated cellulose from OPEFB has the potentials to be used as bionanocomposite reinforcing elements., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The biosynthetic utilization of laccase/mediator system is problematic because the use of organic cosolvent causes significant inhibition of laccase activity. This work explored how the organic cosolvent impacts on the laccase catalytic capacity towards 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) in aqueous solution. Effects of acetone on the kinetic constants of laccase were determined and the results showed Km and Vmax varied exponentially with increasing acetone content. Acetone as well as some other cosolvents could transform ABTS radicals into its reductive form. The content of acetone in media significantly affected the radical scavenging rates. Up to 95% of the oxidized ABTS was successfully recovered in 80% (v/v) acetone in 60 min. This allows ABTS recycles at least six times with 70%-75% of active radicals recovered after each cycle. This solvent-based recovery strategy may help improve the economic feasibility of laccase/ABTS system in biosynthesis.

A mathematical model of a three-phase catalytic reactor, CatReac, was developed for analysis and optimization of a catalytic oxidation reactor that is used in the International Space Station potable water processor. The packed-bed catalytic reactor, known as the volatile reactor assembly (VRA), is operated as a three-phase reactor and contains a proprietary catalyst, a pure-oxygen gas phase, and the contaminated water. The contaminated water being fed to the VRA primarily consists of acetic acid, acetone, ethanol, 1-propanol, 2-propanol, and propionic acid ranging in concentration from 1 to 10 mg/L. The Langmuir-Hinshelwood Hougen-Watson (L-H) (Hougen, 1943) expression was used to describe the surface reaction rate for these compounds. Single and multicompound short-column experiments were used to determine the L-H rate parameters and calibrate the model. The model was able to predict steady-state multicomponent effluent profiles for short and full-scale reactor experiments.