Sustainable and effective methods for biomass pretreatment and biomass cascade utilization are reviewed in this work.

A developed model for estimating the dielectric permittivity of BaTiO ₃ –polymer nanocomposites is proposed by considering the influence of the interphase.

Human physical activity monitoring plays a crucial role in promoting personalized health management. In this work, inspired by an ancient Chinese belt, a belt-type wearable sensor (BWS) based on a triboelectric nanogenerator (TENG) is presented to monitor daily movements and collect the body motion mechanical energy. The developed BWS consists of a soft silicone sheet and systematically connected sensing units made from triboelectric polymer materials including polytetrafluoroethylene (PTFE) and polyamide (PA). A parameter study of the sensing units is firstly conducted to optimize the structure of BWS. The experimental studies indicate that the parameter-optimized BWS unit achieves a maximum output voltage of 47 V and a maximum current of 0.17 μA. A BWS with five sensing units is manufactured to record body movements, and it is able to distinguish different physical activities including stillness, walking, running, jumping, normal breathing, cessation of breathing, and deep breathing. In addition, the developed BWS successfully powers electronic devices including a smartphone, digital watch, and LED lights. We hope this work provides a new strategy for the development of wearable self-powered intelligent devices.

A revised version of the Poon and Shin (PS) model, incorporating the effects of the interphase, is introduced to predict the dielectric permittivity of polymer nanocomposites reinforced with spherical nanoparticles. In this modified approach, both the spherical nanoparticle and its surrounding interphase region are treated as an equivalent nanoparticle, modeled as a core–shell structure. This assumption enables a more accurate representation of the composite, where the polymer matrix and the equivalent nanoparticles form a homogeneous mixture. The process of calculating the dielectric permittivity of the composite occurs in two distinct steps. Initially, the dielectric permittivity of the equivalent particle—comprising both the nanoparticle core and its interphase—is computed. Subsequently, the overall dielectric permittivity of the composite material is determined, considering the properties of the polymer substrate and the equivalent nanoparticles, all within the framework of the modified PS model. To verify the validity of the proposed model, experimental data are compared against the predicted values, showing a high level of agreement when the interphase characteristics are appropriately incorporated. Additionally, the influence of various factors, including the properties of the spherical nanoparticles, the interphase, and the polymer matrix, on the dielectric performance of the nanocomposite is thoroughly investigated. This enhanced PS model offers a valuable theoretical framework for designing polymer–spherical nanoparticle composites with superior dielectric properties, paving the way for their potential application in advanced electronic and energy storage devices.

Multi-stimulus responsive materials have attracted significant attention due to their ability to respond dynamically to multiple external stimuli, including light, temperature, and chemical signals. Achieving both rapid response times and precise selectivity is essential for advancing the functionality of such materials. In this study, five polyoxometalate-based viologen ionic liquids (ILs) were synthesized through ion exchange between H₃PMo₁₂O₄₀ and viologen ILs with varying substituents. These ILs demonstrated multi-stimulus responses to light and ammonia gas. Under Xe lamp irradiation, all ILs exhibited prominent photochromism, with C₁₂–PMo₁₂ undergoing a rapid change from light yellow to light green within just 5 seconds. Exposure to an H₂O₂ atmosphere for 3 hours resulted in the complete decolorization of C₁₂–PMo₁₂. Remarkably, after five cycles of coloring and decoloring, its absorbance remained virtually unchanged, highlighting its excellent reversibility and stability. Additionally, as the alkyl chain length of the viologen-based cation increased, the coloring rate accelerated, and the color contrast enhanced, likely due to the suppression of viologen radical quenching by longer carbon chains. These ILs also exhibited gas-chromic behavior in the presence of ammonia, showing high detection selectivity. Furthermore, the materials were successfully applied in inkless erasable printing and ultraviolet detection. The C₁₂–PMo₁₂-based carbon paper displayed clear and readable prints in only 10 seconds and could be bleached in an H₂O₂ atmosphere within 1.5 hours. These findings demonstrate that the synthesized ILs possess versatile multi-stimulus responsive properties, making them highly promising for applications in inkless printing, ultraviolet detection, and amine vapor sensing.