The year 2024 marked the 50th anniversary of the discovery of the J/ψ particle, which unveiled the charm quark and the charmonium spectrum, instigating the “November Revolution” in particle physics. This discovery catalyzed the development of quenched potential models, most notably the Cornell model, which provided a foundational quantitative description of the hadronic spectrum. However, the landscape of hadron spectroscopy has been profoundly transformed since the turn of the 21st century with the observation of numerous charmonium-like states, such as X(3872), which exhibit properties starkly at odds with quenched model predictions. These discrepancies, exemplified by the “X(3872) low-mass puzzle” and the “Y problem” associated with vector states like Y(4260), underscore the critical limitations of the quenched approximation and signal the necessity for a new theoretical paradigm. This review synthesizes recent advances in hadronic spectroscopy, arguing that the unquenched picture, which incorporates coupled-channel effects such as hadronic loops, is essential for a unified description of these new states and associated anomalies. We demonstrate how unquenched effects provide compelling solutions to long-standing puzzles in charmonium decays (e.g., the “ρπ puzzle” and anomalous dipion transitions), predict and explain the existence of exotic charged states like Zc(3900) and Zb(10610) via mechanisms such as Initial Single Pion Emission, and offer a framework for understanding interactions between charmonia and with nucleons. Furthermore, we emphasize the universality of unquenched effects, extending their application to bottomonium and light-flavor sectors. As experimental precision continues to improve, we advocate for the systematic development of unquenched hadronic spectroscopy, which heralds a new era of high-precision theoretical and experimental studies, moving decisively beyond the quenched approximation to achieve a more complete understanding of non-perturbative behavior of the strong interaction.
Achieving broadband infrared radiation performance with thermal robustness remains a critical challenge for extreme-condition heat management. Here, we propose a dual-regulation strategy coupling configurational entropy engineering with targeted Mn enrichment to synchronously tailor the electronic transitions and lattice vibrations of spinel oxides. Guided by density functional theory (DFT) screening, the Mn-rich high-entropy (HE) spinel(Fe1/8Co1/8Ni1/8Cu1/8Cr1/8Mn3/8)(3)O-4 (HEO-M3) was identified as the optimal composition. Moderate Mn incorporation narrows the band gap to strengthen short-wave carrier absorption, while Mn3+-induced Jahn-Teller (JT) distortions intensify mid-to-long-wave lattice emission. Notably, electron-phonon coupling bridges the broad transition region, creating a continuous near-blackbody spectrum. Experimentally, HEO-M3 delivers outstanding optical performance, achieving high solar-band absorptance (alpha(0.25-2.5 mu m) = 0.914) and mid-to-long-wave emissivity (epsilon(2.5-15 mu m) = 0.885). It demonstrates exceptional high-temperature stability, maintaining epsilon = 0.913 at 10 0 0 degrees C with negligible degradation after 1200 degrees C thermal shocks due to the sluggish diffusion effect. Furthermore, driven by synergistic sol-gel kinetics and thermodynamic entropy stabilization, a single-phase spinel is synthesized at an ultralow 400 degrees C. When applied as a coating, HEO-M3 reaches a 0.948 solar-band absorptance. This work offers a mechanistic framework for entropy-element synergy and an energy-efficient pathway toward highperformance infrared emitters. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
Environmentally friendly bio-based surfactants demonstrate substantial potential for enhancing coal wettability and improving coalbed methane extraction efficiency. This study employed dynamic contact angle measurements, scanning electron microscopy, and Fourier transform infrared spectroscopy to investigate the dynamic evolution of coal wettability under four representative bio-based surfactants. Results demonstrate that all surfactants significantly reduce surface tension relative to pure water, with surface tension exhibiting an initial rapid decrease followed by stabilization as concentration increases. RL exhibits the lowest critical micelle concentration and the maximum surface tension reduction. Dynamic contact angles on coal surfaces decrease substantially after surfactant treatment, with RL achieving the most rapid droplet spreading (contact angle from 50.76 degrees to 23.81 degrees within 3 s). Owens-Wendt surface free energy calculations reveal that RL increases total surface free energy by 15.7 mJ/m2, with polar component enhancement up to 2.6-fold. FTIR peak-fitting analysis indicates that hydrophilic hydroxyl-ether oxygen bond content increases significantly, while aromatic hydrophobic skeleton proportion decreases by 40-60%. SEM analysis indicates that the modified coal surface forms a dense adsorption layer. The wetting enhancement mechanism involves synergistic "functional group reconstruction-surface free energy elevation-interfacial spontaneous imbibition" effects. RL, owing to its dualrhamnosering hydrophilic head groups and dual beta-hydroxy fatty acid hydrophobic tails, achieves optimal performance. This study provides support for optimal wetting agent selection in coal seam water injection.
Nanoparticle reinforcement via additive manufacturing presents a promising strategy to overcome the strength-ductility trade-off in titanium matrix composites (TMCs). Herein, we report the fabrication of Ti60 matrix composites reinforced with coherent Ti2 AlC MAX phase nanoparticles using laser powder bed fusion (LPBF). The LPBF-processed composites exhibit an exceptional combination of ultra-high tensile strength (872 MPa) and ductility (21 % elongation) at 600 degrees C, surpassing the Ti60 matrix alloy by 37 % in strength and 90 % in ductility. Microstructural characterization reveals that rapid solidification enables uniform dispersion of coherent Ti2 AlC nanoparticles along alpha lamellae boundaries, significantly refining the microstructure and increasing dislocation density. Quantitative analysis identifies grain refinement (40 % contribution) and dislocation strengthening (25 % contribution) as the dominant high-temperature strengthening mechanisms. The high-temperature enhanced ductility is attributed to the activation of multiple slip systems and dynamic recrystallization facilitated by high-density dislocations. This work demonstrates the potential of LPBF to synthesize coherent nanoparticle-reinforced TMCs with superior high-temperature mechanical properties. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
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.
