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The lightweight designs of automobiles and space shuttles have raised the bar for aluminum (Al) and its alloys. Graphene (GP) has found widespread application in aluminum matrix composites due to its exceptional mechanical, electrical, and thermal properties. In this study, a successful preparation of 6061Al reinforced with GP was achieved through a powder metallurgy method. This involved mixing GP with 6061Al alloy powders via ball milling, followed by hot-pressing sintering to produce the final GP-reinforced Al alloy nanocomposite. The effect of the pH value of the plating solution on the electroless plating of GP has been studied for the first time. The results show that the strength of the aluminum-matrix composites with copper plating has been significantly improved compared with that of the composites without copper plating. When the pH value of the plating solution is 12, the tensile strength of the composites obtained has been increased by 60.41%. Compared with the matrix material, the conductivity of the composite material has also increased. This work shows that the mechanical behavior of graphene-reinforced metal matrix composites (MMCs) can be improved by adjusting the distribution of graphene coatings, which is of great benefit for the preparation of high strength and lightweight composites with good electrical conductivity. [ABSTRACT FROM AUTHOR]

Hemostatic materials facilitate rapid hemostasis and significantly mitigate the potential of fatal hemorrhage in civilian and military traumas. However, most existing hemostatic materials are limited in material‐dependent forms and fail to integrate multifunctionality, thus constraining their versatility for differing settings and wound healing capacity. Herein, a facile, versatile armor strategy is proposed to endow various biomaterials with rapid hemostasis, infection prevention, and tissue healing capabilities. The armor is fabricated on the surface of substrates first through chemical cross‐linking of adhesive catechol (phenol) and collagen (polyamine) inspired by insect sclerotization, followed by zinc ions (Zn2+) chelation based on mussel‐inspired metal‐phenol coordination chemistry, referred to "metal‐phenol‐polyamine system". This armor facilitates clot formation by promoting platelet aggregation and activating both intrinsic and extrinsic coagulation pathways. Moreover, the integrated Zn2+ endows the armor with potent antibacterial properties against both Gram‐positive and Gram‐negative bacteria. Consequently, this strategy armors a hemostatic sponge that effectively controls bleeding in rabbit hemorrhage models and successfully facilitates the complete healing of epidermal traumas in rats within 14 days. This metal‐phenol‐polyamine system‐assisted armor provides a potential and universal strategy for efficient hemostasis and wound healing. [ABSTRACT FROM AUTHOR]

Drug-eluting stents have been widely used in the clinic because of their impressive ability to reduce restenosis. However, the conventional biodegradable polymers used for drug-loaded coatings undergo bulk erosion, which can induce internal catalysis, resulting in a high local acidity during the degradation process and unfavorable side-effects. Herein, poly(1,3-trimethylene carbonate), a surface eroding biodegradable polymer, was chosen as a drug-loaded coating for cardiovascular stents. We modified both sides of the stent to simultaneously promote re-endothelialization at the inner layer and reduce restenosis at the outer layer, using a titanium oxide (Ti-O) film as the inner layer and a Ti-O film/drug coating as the outer layer. In vitro and in vivo results indicated that the Ti-O film accelerated endothelial cell growth and re-endothelialization, and the drug coating inhibited platelet adhesion, activation, and aggregation, smooth muscle cell proliferation, and significantly reduced neointimal hyperplasia. Therefore, this novel stent may have potential as a cardiovascular stent to treat patients with coronary artery stenosis. [ABSTRACT FROM AUTHOR]