Single-atom catalysts (SACs) are promising low-cost materials for zinc-air batteries, yet simultaneously achieving high density and high intrinsic activity of atomic sites remains a significant challenge. Herein, a sulfur and nitrogen co-doped porous carbon (SNC) featuring high heteroatom contents (16.0 wt
Although glass is recognized as one of the oldest man-made optical materials, its intrinsic structure and formation mechanism are still subject to intense debate. Inspired by the unique formation process of traditional inorganic silicate glass, a new glass fabrication strategy involving deep eutectic-type assembly and structural water hydrogen bonding was proposed. Non-covalent interactions between zinc tetrafluoroborate hydrate (ZTH) and glycylglycine (Gly) prevent the crystallization and aggregation tendencies of ZTH and Gly, favor the formation of deep eutectic melt ZTH-Gly, and endow ZTH-Gly with excellent compatibility with a variety of additives, covering the scope of natural and artificial polymers, carbon materials, metal oxides, organic dyes and pigments, inorganic and organic salts, organic acids and bases, drugs and dietary supplements, and biochemicals. During the phase transition from deep eutectic to glass, structural water generates multiple hydrogen bonds and coordination interactions with ZTH-Gly, significantly increasing its viscosity, mechanical strength, and rigidity.
The extracellular matrix (ECM) provides spatially organized adhesive ligands that regulate cellular adaptation during tissue remodeling and regeneration. Although the effects of ECM composition, ligand density, and mechanical properties on cell behavior have been extensively studied, how cells respond to disrupted ligand spacing in adhesive signals remains poorly understood. Here, we developed a biomimetic nanoscale adhesive platform with precisely controlled Arginine-Glycine-Aspartic acid (RGD) ligand organization to investigate how extracellular adhesive spatial patterns regulate cellular stability at the cell–material interface. Using ordered gold nanoparticle arrays with defined ligand spacings (30 and 150 nm), combined with long-term live-cell imaging, quantitative morphodynamic analysis, focal adhesion characterization, and pharmacological modulation of contractile activity, we demonstrated that nanoscale adhesive organization determines the transition between stable and unstable cellular states. Cells exposed to densely organized adhesive ligands (30 nm spacing) progressively established stable spreading accompanied by focal adhesion maturation, whereas cells encountering sparse adhesive organization (150 nm spacing) exhibited persistent extension–retraction dynamics and failed to achieve morphodynamic stabilization. This unstable phenotype is associated with reduced focal adhesion development and altered coordination between extracellular adhesion and intracellular myosin II-dependent contractile activity. Importantly, inhibition of myosin II-dependent contractility promoted morphodynamic stabilization under sparse adhesive conditions, indicating that adhesion–contractility coordination contributes to nanoscale environment-induced cellular instability. Collectively, this study identifies nanoscale ligand spacing as an important regulator of cellular adaptation and provides mechanistic insights into how spatial disruption of extracellular environments influences cell–biomaterial interactions.
Eucommia ulmoides gum (EUG) is a highly crystalline rubber featuring high modulus and low damping at room temperature, making it a promising underwater acoustic material. However, its complex aggregate structure cannot be fully interpreted using conventional acoustic theories. This study investigates EUG’s mechanical and acoustic transparency regulation mechanisms. Tuning crosslinking density effectively regulates crystallinity and tailors its stress-strain behavior. With rising crosslinking density, EUG’s sound transmission first rises, then falls and finally stabilizes at the low frequency of 3.0–7.5 kHz, while it rises, declines and rebounds at the high frequency of 10–30 kHz. EUG with 3 phr sulfur delivers average transmission coefficients of 0.980 (low frequency) and 0.944 (high frequency). The sound transmission mechanism was explored from the perspectives of grain boundary acoustic loss and acoustic wave propagation. A “block unit” model was proposed to further explain the underlying mechanism. Micro-interface impedance mismatch is a key factor affecting sound transmission. The propagation of sound waves in rubber exhibits a distinct scale effect. Low-frequency waves propagate mainly via elastic crosslinked networks, whereas high-frequency transmission relies on the competition between network elasticity and chain segment viscosity. Fluid–structure interaction simulations further characterize structural stiffness of acoustic components. This study offers new insights for designing underwater acoustic materials.
Simple polythiophenes are promising polymer donors towards the industrialization of organic solar cells (OSCs); however, their photovoltaic properties lag behind their counterparts with complicated structures. Herein, a series of accessible polythiophene derivatives bearing sequentially shortened alkyl side chains, from 2-octyldodecanyl (OD) and 2-hexyldecanyl (HD) to 2-butyloctyl (BO), namely PTETz-OD, PTETz-HD, and PTETz-BO, were designed and synthesized. It was found that the pre-aggregation of the three polymers in solution became stronger with the shortening of their side chains, which promoted ordered molecular packing in the corresponding films. Moreover, the shortest BO chains on PTETz-BO moderate the miscibility between the polymer donor and small-molecule acceptor L8-BO, thereby enabling appropriate nanoscale phase separation and the formation of a well-defined interpenetrating fibrillar network in the active layer of OSCs. Such an optimized morphology facilitates exciton dissociation and charge transport, while tremendously mitigating charge recombination. Consequently, the PTETz-BO:L8-BO OSCs delivered a power conversion efficiency (PCE) of 15.04
