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Understanding the synergistic effects of inorganic minerals and pore structure on coal pore wettability remains a critical knowledge gap. This study investigates the pore-scale wettability mechanism of five high-rank coals by integrating quantitative inorganic mineral analysis, pore morphological characterization, and low-field nuclear magnetic resonance (LF-NMR) T 2 relaxation spectroscopy. A series of water-droplet-coal wetting experiments, organized into three groups, was conducted to establish a cross-scale framework linking physical pore structure, mineral composition and wetting response. The results indicate that the dual mechanism of strong adsorption on hydrophilic mineral surfaces and capillary forces in micropores drives the wetting process. In terms of mineral aspect, clay minerals exhibit significantly higher wettability than non-clay minerals, and clay content shows a significant negative correlation with wetting parameters R g,24h measured by LF-NMR. Notable, when clay content ranges from 2% to 10%, its regulatory effect on pore wettability is particularly sensitive. In terms of pore structure, an exponential saturation model was employed to fit the pore wetting kinetics. The derived kinetic parameters, including the rate constant k and equilibrium pore diameter R eq are consistent with the trends observed in R g,24h . And the 24 h observation is confirmed to represent quasi-steady state for all samples. Additionaly, Pore wettability is governed by absolute pore capacity when pore volume differences exceed approximately two-fold, whereas at smaller differences, micropore complexity and connectivity dominate. Micropores play a critical role due to capillary force-driven physical contributions. Furthermore, a critical pore diameter of 42.16 nm is identified, above which wetting transitions from capillary-driven to surface-spreading or gravity-dominated regimes. A two-dimensional pore-wet coupling model is proposed, and five representative wettability types were defined. Among them, samples C4 and C5 exhibit synergistic enhancement (type A), while C1 shows mutual inhibition (type B). These results provide a new multidimensional coupling paradigm for understanding wettability in heterogeneous porous media.
Advanced oxidation processes (AOPs) using persulfate (PS) activation face practical hurdles such as metal leaching, energy demands, and high costs. This study introduces a metal-free nitrogen-doped graphitic carbon nitride (N@g-C3N4) catalyst as a sustainable PS activator for nonylphenol (NP) degradation. Optimization via central composite design established ideal conditions (pH 5.5, PS 0.42 g L-1, catalyst 0.9 g L-1, NP 5 mg L-1), achieving complete NP removal in 25 min with pseudo-first-order kinetics (k = 0.1968 min(-1)). Radical quenching and electron paramagnetic resonance identified sulfate radicals (SO4 & centerdot;-) as the primary oxidant (55.84% contribution) and hydroxyl radicals (& centerdot;OH) as secondary (33.99%). LC-MS traced a stepwise degradation pathway involving hydroxylation, side-chain oxidation, and ring cleavage to mineralization. Density functional theory revealed that nitrogen doping enhances PS activation through electronic modulation and defect formation in the g-C(3)N(4)framework. The catalyst showed outstanding stability, retaining > 97% activity after ten cycles, and resisted interference from inorganic ions and natural organic matter. In real petrochemical wastewater, the process achieved 60% COD, 35% BOD5, and 31.2% TOC removal, boosting biodegradability (BOD5/COD from 0.23 to > 0.5) and sharply reducing acute toxicity to Daphnia magna (toxicity units from 5.66 to 0.51). Operating under ambient conditions without external energy and with a low oxidant cost (similar to 0.42-0.84 USD m(-3)), the PS/N@g-C(3)N(4)system offers an economically viable, eco-friendly, and scalable solution for treating endocrine-disrupting contaminants in industrial wastewater.
Inspired by biomimetic concepts, this study aimed to screen potential calcium-chelating peptides (CCPs) from embryonic egg white (EEW) using an integrated approach combining separation-purification methods, peptidomics technology, and molecular simulation. Through separation-purification approach and molecular docking, 3 key skeleton CCPs, including MAQRASDLF, VVLRQDLMA, and LAEVSKPHAE, were identified from EEW (EEW-CCPs). These peptides, containing amino acids such as Glu and Arg, demonstrated strong calcium-binding capability. Additionally, using peptidomics combined with molecular docking, 3 vital EEW-CCPs-GRCELAAAMKR, AEVDCSRFPN, and CRPTVQAQST-containing amino acids like Arg and Ser were screened and shown to possess strong calcium chelation properties. This study provides both novel insights and a systematic comprehensive approach for screening active CCPs from food sources. (c) 2027 The authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Layered oxide cathodes for potassium-ion batteries (PIBs) undergo substantial structural strain during cycling because of the large K+ radius. Here, Co modification is introduced into O3-type Na-0.Cr-8(0).Ti-8(0).O-2(2) to regulate structural evolution and electrochemical reversibility. The resulting Na-0.Cr-8(0).Ti-8(0).Co-15(0).O-05(2) (NCTCO) contains substitutional Co in the layered host together with localized CoCr2O4 spinel domains. NCTCO delivers 70.3 mA h g(-1) at 1000 mA g(-1) and retains 96.4% capacity after 500 cycles at 500 mA g(-1) in K-metal half-cells. Electrochemical analysis shows a lower charge-transfer resistance after Co modification. In situ XRD reveals reduced lattice variation during the first charge, with a three-layer-equivalent c-axis expansion of 1.10% compared with 2.50% for NCTO, together with suppression of a high-voltage P1-type component. DFT calculations using idealized layered models indicate that substitutional Co lowers a representative K-ion migration barrier from similar to 0.45 to 0.39 eV. These results show that Co modification improves the structural reversibility and electrochemical stability of the O3-type layered cathode while clarifying the distinct experimental and modeled roles of the two Co environments.
Moisture removal is a standard pretreatment to improve lignocellulosic biomass fuel quality, yet its precise impact on fire safety remains insufficiently decoupled from intrinsic fuel chemistry. This study investigates the multi-scale combustion behavior of Pinus sylvestris across a systematic moisture gradient (0% to similar to 30%) to separate intrinsic combustion energetics from macroscopic fire hazards. Microscale characterizations via FTIR, TGA, and microscale combustion calorimetry (MCC) reveal that moisture variations do not alter the biopolymer chemical structure, fundamental degradation pathways, or inherent heat release capacity. The intrinsic chemical energy density is strictly preserved. Conversely, bench-scale tests demonstrate that moisture removal exponentially amplifies physical fire hazards. Cone calorimetry indicates that drying eliminates the endothermic thermal buffering of water, substantially advancing ignition and accelerating the fire growth rate index by up to 36.6% under intense radiant heat. Furthermore, smoke density testing shows that the absence of vapor dilution in dried wood drastically intensifies early-stage smoke accumulation, increasing the 4-min visibility hazard by over sixfold. These findings reveal a fundamental decoupling: moisture acts solely as a governing thermophysical state variable regulating heat transfer and volatile dynamics, rather than modifying the intrinsic chemical energy of the matrix. This study provides a mechanistic framework for balancing energy efficiency and fire safety in biomass utilization.
