Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202507085
This study investigates the spatiotemporal differentiation of suspended particulate matter (SPM) characteristics, sources, and their impacts on water quality between the Middle Route (closed artificial channel) and East Route (open natural water system) of the South-to-North Water Diversion Project. Thirty sampling sites (13 on the Middle Route, 17 on the East Route) were established, and samples were collected during dry and wet seasons. Water quality parameters and SPM characteristics were analyzed, including particle size distribution, total suspended solids (TSS), chlorophyll a, and stable carbon and nitrogen isotopes. Results show that the Middle Route maintains good and stable water quality, with SPM dominated by coarse particles (>63 μm, 61.43%–94.68%), total phosphorus (TP) <0.01 mg·L−1, and a significant positive correlation between chlorophyll a and coarse particles (r=0.60), indicating algal aggregation dominates particle formation. In contrast, the East Route exhibits high and fluctuating nitrogen and phosphorus concentrations, with SPM dominated by fine particles (<20 μm, 51.26%–88.61%), TP ranging from 0.03 to 1.11 mg·L−1, and a positive correlation with fine particles, suggesting significant external inputs. Carbon and nitrogen isotope analysis reveals that Middle Route SPM primarily originates from autochthonous algae (contribution >46.75%), while East Route SPM is influenced by both terrestrial C3 plants and algae. The distinct engineering and management approaches of the two routes lead to significant differences in SPM characteristics and sources, thereby affecting water quality dynamics. The Middle Route requires an 'algal reduction and hydrodynamic optimization' strategy to control algal-derived coarse particle deposition, whereas the East Route benefits from 'retention-sedimentation and wetland purification' to reduce external fine particles and pollutant inputs. This research provides theoretical support and practical guidance for differentiated SPM management in long-distance water diversion systems.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2024110202
Anaerobic digestion (AD) is an environmentally friendly biochemical technology for waste treatment and renewable energy production, yet its methane conversion efficiency remains suboptimal. This study employed flux balance analysis (FBA) to determine the optimal temperature for methane production in AD, and subsequently regulated key flexible nodes in the metabolic pathway to maximize methane flux. At the optimal temperature of 40 °C, up-regulating the acetyl-CoA flexible node increased methane flux by 48.5%, while up-regulating the acetate node increased it by 36.6%. The higher improvement via acetyl-CoA regulation is attributed to the fact that 40 °C is unfavorable for hydrogen-producing acetogenic bacteria, making acetyl-CoA the critical control point. These findings demonstrate that flexible node regulation can overcome the limitations of temperature optimization alone. The FBA methodology provides a reliable, cost-effective approach for optimizing target product yields in AD and other fermentation systems, requiring only input and output measurements to resolve intermediate metabolic fluxes.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202509004
Acetone, a widely used solvent in the pharmaceutical industry, poses environmental and economic challenges due to its high volatility and the low concentration of acetone in water-based absorbents, which complicates recovery. This study proposes a composite absorbent comprising 1,4-butanediol (BDO), triethylene glycol, sodium citrate, and water, aiming to enhance acetone absorption capacity and enable cost-effective resource recovery. Response surface methodology optimized the absorbent composition to BDO 35%, triethylene glycol 10%, and sodium citrate 5%, achieving an acetone absorption capacity of 51.97 g·kg−1, which is 2.39 times that of pure water (21.77 g·kg−1). Density functional theory (DFT) calculations and AIM topological analysis revealed that BDO forms stronger hydrogen bonds with acetone, characterized by shorter bond lengths and higher electron density, underpinning its superior molecular recognition and absorption capability. Process simulation of absorption-regeneration cycles demonstrated that, compared to pure water, the composite absorbent reduces absorbent consumption by 36.2% and regeneration energy consumption by 41.15% while achieving effluent acetone concentrations below 100 mg·m−3. This multi-scale investigation, spanning macroscopic experiments, molecular mechanisms, and process simulation, validates the feasibility and advantages of BDO-based composite absorbents for VOC control, providing theoretical and data support for the engineering application of alcohol-based absorbents in efficient organic pollutant separation.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4086-4
Interventional therapy has emerged as a transformative alternative to open surgery owing to its minimal invasiveness and fast recovery. However, it still presents risks of iatrogenic injury from vascular access, necessitating prompt and reliable vascular closure. Although various closure systems have been developed, they often suffer from complicated deployment procedures, potential for loosening, and risk of device migration. Herein, we develop a smart self-deployable vascular closure device enabled by a semi-interpenetrating network (sIPN) that synergistically integrates a programmable shape memory effect and robust tissue adhesion. The sIPN was designed by interpenetrating flexible, dopamine-functionalized poly(tetrahydrofuran) (PTD) chains into a photo-crosslinkable poly(ε-caprolactone)-based copolymer (PCC) network. The vascular closure model was fabricated via a UV-assisted fused deposition modeling printing strategy, significantly reducing mechanical anisotropy while facilitating structural customization. The resulting device exhibits autonomous self-deployment at 37 °C, along with reliable tissue adhesion under physiological conditions (maximum shear strength of 150.5 kPa). In vitro, the material demonstrates exceptional hemocompatibility (below 3%) and excellently enhanced cell migration (up to 38.9%). In vivo, immunofluorescence analysis reveals a promotion for CD31 (162.18%) and αSMA (154.93%) compared to the control group. These results highlight the PTD/PCC sIPN as a bioadaptive, multifunctional material platform for intelligent vascular closure, offering great promise for clinical translation in interventional therapies.