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Based on the characteristics and laws of coal spontaneous combustion in Yanzhou Mining Area, this paper studies the construction of accurate prevention and control system of coal spontaneous combustion, including the research on accurate fire prevention and control of coal spontaneous combustion prediction, monitoring and early warning and advanced disposal. Through the establishment of a 15 t large-scale coal spontaneous combustion testbed to study the characteristics of coal spontaneous combustion, the research and development of infrared thermal imaging technology to determine hidden fire sources, and the development of a series of new fire-fighting materials, technologies and equipment, the three leaps of forward development of “effective management, early prediction and early control, and ahead of time prevention” of coal fire disasters has been realized, and a scientific coal spontaneous combustion technology and management system has been formed in terms of management, equipment and technology; the research results promote the three major changes of coal seam fire from “passive control to advanced prevention and control, from traditional technology to high-tech, and from decentralized practical technology to complete set of applicable technologies”, and build three lines of defense for natural fire disaster “advanced prediction, early prevention, and rapid emergency control”, so as to achieve accurate prevention and control of coal spontaneous combustion in Yanzhou Mining Area.

Developing efficient metal‐nitrogen‐carbon (M‐N‐C) single‐atom catalysts for oxygen reduction reaction (ORR) is significant for the widespread implementation of Zn‐air batteries, while the synergic design of the matrix microstructure and coordination environment of metal centers remains challenges. Herein, a novel salt effect‐induced strategy is proposed to engineer N and P coordinated atomically dispersed Fe atoms with extra‐axial Cl on interlinked porous carbon nanosheets, achieving a superior single‐atom Fe catalyst (denoted as Fe‐NP‐Cl‐C) for ORR and Zn‐air batteries. The hierarchical porous nanosheet architecture can provide rapid mass/electron transfer channels and facilitate the exposure of active sites. Experiments and density functional theory (DFT) calculations reveal the distinctive Fe‐N2P2‐Cl active sites afford significantly reduced energy barriers and promoted reaction kinetics for ORR. Consequently, the Fe‐NP‐Cl‐C catalyst exhibits distinguished ORR performance with a half‐wave potential (E1/2) of 0.92 V and excellent stability. Remarkably, the assembled Zn‐air battery based on Fe‐NP‐Cl‐C delivers an extremely high peak power density of 260 mW cm−2 and a large specific capacity of 812 mA h g−1, outperforming the commercial Pt/C and most reported congeneric catalysts. This study offers a new perspective on structural optimization and coordination engineering of single‐atom catalysts for efficient oxygen electrocatalysis and energy conversion devices. [ABSTRACT FROM AUTHOR]

Formic acid has emerged as a highly promising hydrogen storage material, and the development of efficient catalysts to facilitate its dehydrogenation remains imperative. In this study, a novel catalyst consisting of palladium nanoparticles supported on boron-doped porous carbon (Pd/BPC) was successfully synthesized to enable efficient hydrogen production through the dehydrogenation of formic acid. The impacts of the boron doping ratio, doping temperature, and palladium reduction temperature on the catalyst's performance were systemically investigated. The results demonstrated the Pd/BPC catalyst synthesized with a carbon-to-boron ratio of 1:5 by calcination at 900 °C and subsequent reduction at 60 °C exhibited superior formic acid dehydrogenation performance, being 2.9 and 3.8 times greater than that of the Pd/PC catalysts without boron doping and commercial Pd/C, respectively. Additionally, the catalyst showed excellent cycle stability with no significant activity reduction after five consecutive cycles. Experimental and theoretical results reveal that boron doping not only facilitates the homogenous distribution of Pd nanoparticles but also induces a stronger support–metal interaction, thereby reinforcing the catalytic performance. This research is expected to provide valuable insights into the economically viable and efficient production of environmentally friendly hydrogen energy. [ABSTRACT FROM AUTHOR]

Aim: Continental comparisons of migration strategies within and between populations of single species are rare but can be insightful to understand key environmental factors shaping differences in migration systems. We investigated differences in stopover networks and migration strategies between three separate Eurasia Greater White‐fronted Geese (GWFG) Anser albifrons populations to better understand how each overcomes the different topographic challenges faced along their migration routes during spring and autumn. Location: Eurasia. Taxon: Birds. Methods: Using 106 (autumn) and 65 (spring) tracks from tagged GWFG from three Eurasian populations (Baltic‐North Sea [BNS] in the west; East Asia Continental [EAC] and West Pacific [WP] in the east), we generated stopover networks, calculated network metrics, quantified migration parameters and compared variation between populations and seasons. Results: BNS showed largest network size, shortest average geodesic distance in both seasons, shortest migration distances, most stopover sites, longest stopover duration and shortest step length. EAC showed longest migration distance and second maximal flight length (>1600 km). WP showed shortest migration durations and longest maximal flight length (>2500 km). Summering ground arrival dates did not differ between populations. Autumn migration duration was shorter and migration speed faster than in spring in all populations. Main Conclusions: We infer lack of obvious ecological barriers to BNS geese shapes their frequent stopovers of short duration. In contrast, EAC geese face two major ecological barriers (3100 km boreal forest, high mountains, dense human settlement and ocean) and WP geese must pass c. 2400 km of forest, mountains and ocean along their migration corridors, necessitating longer staging and migration segments of greater duration. We conclude that, despite almost identical body plan, all populations respond to radically different topographic challenges, adapting to meet these using different movement strategies, balancing migration schedule and fat accumulation patterns with availability and quality of stopovers. [ABSTRACT FROM AUTHOR]