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Wide color gamut displays are considered a new generation of display technology owing to their excellent color saturation and color rendition. However, a significant challenge in their development is obtaining narrow-band green-emitting phosphors with high quantum efficiency and low thermal quenching. Herein, we address this challenge by constructing efficient Eu2+ → Mn2+ energy transfer in the KAl4Ga7O17 matrix. This approach allows us to obtain a high quantum efficiency narrow-band green-emitting phosphor that can be excited by a UV LED chip. By achieving a 95.6% energy transfer efficiency of Eu2+ → Mn2+, the KAl4Ga7O17 : 0.1Eu2+,0.12Mn2+ (KAGO:0.1Eu2+,0.12Mn2+) phosphor exhibits nearly single-band emission peak at 509 nm with a full-width at half maximum (FWHM) of only 25 nm. Moreover, the internal quantum efficiency reaches 99% under 330 nm excitation. Compared with the undoped Ga sample, this phosphor demonstrates a 2.2 times increase in luminescence intensity. This improvement can be attributed to the introduction of Ga3+, enhancing the absorption of phosphors. Finally, as an application demonstration, we used KAl4Ga7O17:0.1Eu2+,0.12Mn2+ green phosphor, BaMgAl10O17:Eu2+ blue phosphor, and K2SiF6:Mn4+ red phosphor in combination with a 365 nm UV LED chip to encapsulate a white LED device, which gave a color gamut area of 122% NTSC and 91% Rec.2020 with a luminous efficacy of 27.09 lm W−1. Further, we fabricated a light bar and assembled it into an LCD screen. The fabricated LCD screen exhibited superior color rendition compared to ordinary commercial screens. [ABSTRACT FROM AUTHOR]

Light-weight, high-strength, aluminum (Al) alloys have widespread industrial applications. However, most commercially available high-strength Al alloys, like AA 7075, are not suitable for additive manufacturing due to their high susceptibility to solidification cracking. In this work, a custom Al alloy Al92Ti2Fe2Co2Ni2 is fabricated by selective laser melting. Heterogeneous nanoscale medium-entropy intermetallic lamella form in the as-printed Al alloy. Macroscale compression tests reveal a combination of high strength, over 700 MPa, and prominent plastic deformability. Micropillar compression tests display significant back stress in all regions, and certain regions have flow stresses exceeding 900 MPa. Post-deformation analyses reveal that, in addition to abundant dislocation activities in Al matrix, complex dislocation structures and stacking faults form in monoclinic Al9Co2 type brittle intermetallics. This study shows that proper introduction of heterogeneous microstructures and nanoscale medium entropy intermetallics offer an alternative solution to the design of ultrastrong, deformable Al alloys via additive manufacturing. Commercial high-strength Al alloys often suffer from cracking during additive manufacturing. Here, the authors present an additively manufactured, a strong and plastically deformable Al alloy with heterogeneous nanoscale intermetallics. [ABSTRACT FROM AUTHOR]

With increasing recognition of randomness and time-variance of variables in structural assessment, time-dependent reliability (TdR) methods have gained popularity among researchers and practitioners. This paper critically reviews commonly used TdR methods, with focuses on analytical solutions, hybrid solutions and simulation solutions. Through this review and analysis, research challenges for TdR methods are identified and future research directions are proposed. It is found that Rice formula-based solutions are accurate but have limited solutions, hybrid solutions are efficient but affected by non-Gaussianity and nonlinearity of limit state functions, and simulation solutions are robust but time-consuming for complex structure systems. It is also found that the effectiveness of TdR methods depends highly on the complexity of limit state functions and types of stochastic processes involved, in particular, the stationarity, Gaussianity and correlation. The contribution of this review is that different TdR methods are elucidated and future research directions are proposed. [ABSTRACT FROM AUTHOR]