Alloy design based on single–principal-element systems has approached its limit for performance enhancements. A substantial increase in strength up to gigapascal levels typically causes the premature failure of materials with reduced ductility. Here, we report a strategy to break this trade-off by controllably introducing high-density ductile multicomponent intermetallic nanoparticles (MCINPs) in complex alloy systems. Distinct from the intermetallic-induced embrittlement under conventional wisdom, such MCINP-strengthened alloys exhibit superior strengths of 1.5 gigapascals and ductility as high as 50% in tension at ambient temperature. The plastic instability, a major concern for high-strength materials, can be completely eliminated by generating a distinctive multistage work-hardening behavior, resulting from pronounced dislocation activities and deformation-induced microbands. This MCINP strategy offers a paradigm to develop next-generation materials for structural applications.

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The substituted p-phenylenediamines (PPDs) represent a suite of effective antioxidants broadly applied in rubber industries. However, knowledge of their environmental occurrences and fate remains extremely limited. Herein, we explored the occurrence of six major PPD antioxidants and one newly defined transformation product in dust particles from different environments, including roads, underground parking lots, vehicles, and houses. The majority of the PPDs exhibited ubiquitous occurrence in these environments. Median concentrations of total PPDs were determined to be 226 ng/g in road dust, 232 ng/g in parking lot dust, and 156 ng/g in vehicle dust, orders of magnitude greater than those in house dust (14.0 ng/g). Different composition profiles of PPDs were also found between house dust and vehicle-related dust, likely indicating the influence of vehicle tires or other rubber products. In addition, a major ozonation product of N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine (6PPD), 6PPD-qunione, was also identified in dust with levels (median range of 32.2–80.9 ng/g) comparable to that of 6PPD except in house dust. To the best of our knowledge, this is the first systematic investigation of the occurrence of major PPD antioxidants and 6PPD-qunione in various dust matrices. Our findings would attract attention to their environmental fate and ecological and human health risks.

The intracellular uptake and subcellular localization of carbon nanotubes strongly depend on the physical size of the materials. Multiwalled carbon nanotubes (MWNTs; 0.5–2 μm in length, 10–30 nm in diameter) are excluded from the interior of the cell; long single‐walled carbon nanotubes (L‐SWNTs) of length 100–200 nm (1–3 nm in diameter) are only internalized into cytoplasm, whereas short ones (S‐SWNTs) of length 50–100 nm partly reside in the cell nucleus.

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