SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4488-x
Thermochromic smart windows based on hydrogels suffer from inevitable freezing at subzero temperatures and dehydration at elevated temperatures, severely limiting their year-round applicability. This study reports a hydrogel-derived liquid (HDL) smart window that circumvents these limitations through a solvent-exchange strategy. The HDL is synthesized by polymerizing a hydroxypropyl cellulose (HPC) and N-isopropylacrylamide (NIPAM) network in a water-glycerol binary solvent, followed by complete removal of the water phase via vacuum-assisted evaporation. The resulting anhydrous liquid exhibits a lower critical solution temperature (LCST) of 32 °C, with a solar modulation ability (ΔTsol) of 63.2% and a luminous transmittance (Tlum) of 88.1% in the clear state. Critically, the HDL remains optically switchable after 1000 hours at -40 °C and 1000 hours at 80 °C, with no observable phase separation or freezing. The smart window prototype demonstrates a 12.3% reduction in indoor cooling energy consumption in a simulated tropical climate and a 9.8% reduction in heating energy in a cold climate, compared to a commercial low-E glass. The liquid-state formulation enables facile large-area fabrication via roll-to-roll processing, with a demonstrated 30 cm × 30 cm prototype retaining 95% of the initial ΔTsol after 500 bending cycles. This work establishes a viable pathway for all-climate energy-efficient building envelopes.
Journal of Fuel Chemistry and Technology•2026•DOI: 10.3724/2097-213X.2025.JFCT.0024
This study investigates the thermochemical conversion behavior of microalgae pellets in a molten hydroxide salt (80% NaOH-20% Na2CO3) system and its influence on hydrogen production. By comparing temperature evolution, gas release characteristics, and structural evolution of pellets with and without molten salt, and integrating char alkalization experiments, the regulatory mechanism of molten salt on reaction pathways and hydrogen production was systematically analyzed. Results indicate that molten salt significantly enhances internal heat transfer efficiency, achieving a central heating rate of 177 °C/s, effectively alleviating thermal hysteresis. Concurrently, molten salt promotes pore development through penetration, erosion, and catalytic effects, resulting in a porosity increase of 53.2%–104.3% after 10 s of reaction. Conversion efficiency is markedly improved, with the dominant reaction pathway shifting to char alkalization after only 70 s. Furthermore, when heating rate is increased above 600 °C, hydrogen yield from char alkalization improves more significantly, primarily attributed to the synergistic promotion of molten salt catalysis and rapid heating on volatiles reforming. This study provides a theoretical foundation for understanding efficient hydrogen production from biomass in molten hydroxide salts.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202604009
Biological nitrogen removal in wastewater treatment plants (WWTPs) is often limited by insufficient influent carbon sources, necessitating external carbon addition to enhance denitrification. Conventional single carbon sources, such as sodium acetate, frequently fail to meet the metabolic demands of complex microbial communities, compromising nitrogen removal efficiency and stability. Composite carbon sources, by providing multiple electron donors, can improve metabolic cooperation among microorganisms, yet their underlying microbial mechanisms remain insufficiently understood. In this study, activated sludge from a municipal WWTP was used to investigate the microbial mechanisms of composite carbon sources during denitrification. Batch denitrification experiments were conducted in combination with metagenomic and metatranscriptomic analyses to systematically characterize microbial community structure and functional gene expression under different carbon source conditions. Results showed that, compared with sodium acetate as the single carbon source, the composite carbon source system (sodium acetate: sodium succinate: ethanol = 2:1:3) increased the denitrification rate from (6.822 ± 0.141) mg/(L·h) to (8.370 ± 0.186) mg/(L·h), representing a 22.7% improvement, while reducing N2O accumulation by approximately 55%. Metagenomic analysis revealed that Ottowia, Rubrivivax, Thauera, and Zoogloea were the dominant denitrifying genera. Metatranscriptomic results further demonstrated that the composite carbon sources significantly upregulated the transcription of key denitrification genes, with nirS, norB, and nosZ increasing by 37.8%, 27.4%, and 48.6%, respectively. In addition, the composite carbon sources promoted complementary carbon metabolic strategies among different microbial communities, enhancing electron donor supply and improving denitrification efficiency. These findings indicate that composite carbon sources synergistically enhance denitrification performance through regulation of functional gene transcription in complex microbial communities, providing a theoretical basis for carbon source optimization in WWTPs.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025011303
Polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants with environmental persistence, bioaccumulation, and toxicity, posing significant threats to marine ecosystems and human health. This study developed an analytical method using anhydrous sodium sulfate-alumina composite column chromatography coupled with gas chromatography-orbitrap mass spectrometry to quantify mono- to deca-BDEs in coastal seawater of Dalian, China. The total PBDE concentrations (∑PBDEs) ranged from not detected to 511.96 pg·L−1, with a mean of 163.96 pg·L−1. BDE-209 was the dominant congener, contributing 24.1% to ∑PBDEs. Spatial distribution exhibited distinct heterogeneity, with higher abundances of highly brominated PBDEs near sewage discharge outlets. Partial least squares discriminant analysis indicated that anthropogenic activities, particularly sewage discharge, were the primary sources. Ecological risk assessment revealed extremely low risk, with the highest risk quotient of 0.013 for BDE-17. These findings provide baseline data for PBDE contamination in Dalian coastal waters and underscore the need for continued monitoring of emerging contaminants.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025030303
Emerging organic pollutants (EOPs) represent a class of toxic and hazardous chemicals characterized by ecotoxicity, environmental persistence, and bio-accumulation. Conventional water treatment processes have proven inadequate in eliminating these EOPs, leading to their accumulation in aquatic ecosystems and posing severe threats to the health and safety of aquatic organisms. Consequently, the development of efficient technologies for the complete elimination of EOPs from water matrix is of great importance. Recently, carbon nitride (CN)-based photocatalytic degradation technologies have been extensively utilized for the efficient treatment of organic pollutants in water environments due to their advantages of being green, efficient, and cost-effective. Furthermore, the catalytic activity of CN-based photocatalytic systems can be significantly improved and energy recovery can be achieved via coupling these systems with other advanced oxidation technologies. This review provides a critical review of the modification strategies for CN photocatalytic materials and their application in photocatalytic coupling systems toward EOPs elimination. Moreover, the opportunities and challenges on the photocatalytic coupling systems have been discussed.