Alkali metal poisoning of NH3 selective catalytic reduction (NH3-SCR) catalysts remains a critical bottleneck in NOx control for stationary pollution sources. In this study, a hollow Mn0.1TiOx nanotube (MT-T) catalyst was constructed through an in-situ co-growth strategy, enabling precise tuning of its microstructure and surface properties. Compared with conventional nanoparticles (MT-N), MT-T exhibited a larger specific surface area (280 m2/g), a higher density of acid sites, and superior structural stability, achieving nearly 100% NO conversion and high N2 selectivity over a wide temperature range of 150-390 degrees C. Even after 2 wt% K poisoning, MT-T maintained excellent catalytic activity, demonstrating remarkable resistance to alkali metal poisoning. H2TPR, NH3-TPD, XPS, and other characterization results indicated that K poisoning typically induces structural changes in the catalyst, loss of acid sites, and perturbation of its electronic environment, whereas in MT-T, the cooperative effect between the hollow nanotube structure and the strong K-Ti interaction markedly mitigates these adverse effects, thereby better preserving its active sites, which was helpful for achieving excellent SCR performance.
Spin polarization of metal active centers provides a powerful means to mitigate the spin flipping of key intermediates during electrocatalysis. However, effectively triggering spin polarization and establishing its relationship with performance in oxygen reduction/evolution reactions (ORR/OER) remain challenging. This study proposes a defect engineering means that creates selenium vacancies (SeV) in cobalt diselenide (CoSe2) integrated onto an iron single-atom platform (FeSA@CoSe2-SeV) to enhance Co's spin polarization. FeSA@CoSe2-SeV achieves a high ORR half-wave potential (0.921 V) and a low OER overpotential (370 mV@10 mA cm-2), significantly outperforming FeSA@CoSe2. When applied to zinc-air battery (ZAB), it achieves a high power-density (186 mW cm-2), with a cycling life of up to 582 h. FeSA@CoSe2-SeV-based flexible ZAB maintains stable charge/discharge performance even under 0 degrees-180 degrees bending conditions. Introduction of SeV reduces the degeneracy of the Co 3d orbitals, effectively triggering spin polarization. This electronic structure reconstruction causes the pi* orbital of Co-*O/*OH to lose an electron, enhancing the hybridization between Co 3d and *O/*OH 2p orbitals and thereby mitigating the intermediates' spin flipping. Ferromagnetic FeSA stabilizes the SeV and Co active sites, ensuring the structural/catalytic stability. This work confirms the effectiveness of SeV-induced spin polarization regulation, providing a novel spintronics-based approach for designing bifunctional electrocatalysts.
Plant–soil feedbacks (PSFs) are fundamental processes linking plant performance to soil biotic and abiotic dynamics, thereby shaping ecosystem structure, productivity, and stability. Root exudates have emerged as central regulators of PSFs, functioning not only as nutrient sources but also as signaling molecules that orchestrate rhizosphere microbial assembly and soil processes. However, a mechanistic synthesis of how diverse exudate classes drive PSFs across ecological contexts remains lacking. Here, we synthesize recent advances in understanding how root exudates mediate PSFs through selective microbial recruitment, nutrient mobilization, and activation of plant defense pathways. We emphasize the dynamic and context-dependent nature of exudation, which varies with plant species, developmental stage, and environmental stress, enabling plants to strategically reprogram their rhizosphere microbiome. Particular attention is given to organic acids, phenolic compounds, and benzoxazinoids as key chemical regulators integrating above- and belowground signaling to suppress soil-borne pathogens and plant-parasitic nematodes. Finally, we discuss ecological and agricultural implications, identify critical knowledge gaps, and propose future research directions for harnessing exudate-mediated PSFs to improve soil health and crop resilience under global environmental change.
Direct-buried heating pipelines are difficult to inspect directly, and underground operating conditions make timely detection of leakage, blockage, and structural deterioration challenging. To address this problem, this study develops an Internet of Things (IoT)-based monitoring system for direct-buried heating pipelines. A four-layer architecture, consisting of the perception layer, network transport layer, data processing layer, and application layer, was designed to integrate multi-parameter sensing, data transmission, storage, visualization, and alarm functions. The system was implemented and validated in two urban heating-pipeline projects. Field results demonstrate that the proposed system can reliably collect and transmit temperature, strain, displacement, and flow-rate data in real time with a sampling and upload interval of 60 s, providing continuous condition awareness of pipeline operation. The monitoring platform supports real-time visualization, historical data retrieval, and threshold-based alarm, enabling timely identification of abnormal conditions and improving operational decision-making. The field deployments further confirm the feasibility, stability, and engineering applicability of the proposed sensing–transmission–monitoring workflow under real service conditions. By enabling early fault warning and supporting predictive maintenance, the proposed system contributes to safer, more efficient, and more reliable management of urban heating networks.
The advanced oxidation process based on persulfates is currently one of the most mainstream methods for treating water pollution. If the synthesized catalyst material can efficiently activate persulfates while also synergistically utilizing light irradiation to some extent, it would better meet practical demands. Here, a composite heterojunction of MoS2/CoMn2O4 was prepared using a hydrothermal technique of activating PMS to deform ceftriaxone sodium in water. The experimental findings show that the nanosheet-like MoS2 which forms a bridging structure with CoMn2O4 microspheres was found to greatly improve visible-light harvesting and consequently improve the activation kinetics of the PMS. It was found that the system could degrade to a level of 85
