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In order to provide a sufficient theoretical basis for the fatigue‐resistant design of the aircraft wheels, strain‐controlled low‐cycle fatigue (LCF) tests were carried out on specimens machined in the extrusion direction (ED) and transverse direction (TD) of die‐forged 2014 aluminum alloy wheels. Although the TD specimens have lower tensile strength and yield strength, the fatigue test results show that the TD specimens have superior fatigue life compared with the ED specimens at total strain amplitudes of 0.5–0.8%. This is predominantly caused by the coarse Al12(MnSi)2(FeCu) intermetallic particles close to the surface layer, which results in a relatively short crack initiation stage for the ED specimens. In contrast, TD specimens with finer and more uniform recrystallized grains exhibit more excellent resistance to fatigue crack initiation (FCI) and propagation (FCP). Moreover, the fatigue life of alloys could be accurately predicted via a Manson–Coffin–Basquin (MCB) model based on total strain. Highlights: A new die forging method was used to fabricate the aircraft wheel.Fatigue characteristics and fracture behavior of aircraft wheels were explored.The accuracy of different fatigue life prediction models was evaluated.Coarse Al12(MnSi)2(FeCu) intermetallic particles affected fatigue crack initiation. [ABSTRACT FROM AUTHOR]

In this work, (100)-oriented Pr-doped (Bi0.5Na0.5)TiO3–BaTiO3 ferroelectric/photoluminescence film was fabricated on SrRuO3-electroded Pb(Mg1/3Nb2/3)O3–PbTiO3 single-crystal substrate. The phase structure, domain, ferroelectric, and photoluminescence performance were studied. Results indicated the Pr-BNBT thin film has pure phase structure, dense microstructure, and exhibited (100) orientation out of the plane. Well-defined ferroelectric hysteresis loop with the remanent polarization of ~ 18 μC/cm2 and obvious photoluminescence emission spectrum were obtained. Based on the piezoresponse force microscopy, the ferroelectric domain structure was characterized and the domain size was ~ 100 nm. The present ferroelectric/photoluminescence multifunctional thin film has potential for multifunctional MEMS actuator and optical devices. [ABSTRACT FROM AUTHOR]

A new lead-free perovskite piezoelectric solid solution (1−x)BaTiO3–xZnSnO3 (BT–xZS) was designed and fabricated using the traditional solid-state reaction method. The introduction of ZnSnO3 was found to shift the high-temperature cubic phase of BaTiO3 to lower temperatures. At room temperature large electrostrictive coefficient up to 0.0452 m4 C−2 was obtained in BT–0.10ZS ceramic, which is much larger than the traditional electrostrictive material Pb(Mg1/3Nb2/3)O3 and recently reported lead-free electrostrictive systems. The large electrostrictive response of BT–xZS ceramics makes them quite potential to be applied to new solid-state actuators. [ABSTRACT FROM AUTHOR]

Background: The rapid detection of Mycobacterium tuberculosis (MTB) is essential for controlling tuberculosis. Methods We designed a portable thermocycler-based real-time fluorescence loop-mediated isothermal amplification assay (cyp141-RealAmp) using six oligonucleotide primers derived from cyp141 to detect MTB. A combined number of 213 sputum samples (169 obtained from clinically diagnosed cases of pulmonary TB and 44 from a control group without tuberculosis) underwent Acid-fast bacillus (AFB) smear, culture, Xpert MTB/RIF assays, and cyp141-RealAmp assay., Results: By targeting MTB cyp141, this technique could detect as low as 10 copies/reaction within 30 min, and it was successfully rejected by other mycobacteria and other bacterial species tested. Of the 169 patients, there was no statistical difference between the detection rate of cyp141-RealAmp (92.90%, 95% CI: 89.03-96.07) and that of Xpert MTB/RIF (94.67%, 95% CI: 91.28-98.06) ( P > 0.05), but both were statistically higher than that of culture (65.68%, 95% CI: 58.52-72.84) ( P < 0.05) and AFB (57.40%, 95% CI: 49.94-64.86) ( P < 0.05). Both cyp141-RealAmp and Xpert MTB/RIF had a specificity of 100%. Furthermore, a high concordance between cyp141-RealAmp and Xpert MTB/RIF was found ( Kappa = 0.89)., Conclusion: The cyp141-RealAmp assay was shown to be effective, responsive, and accurate in this study. This method offers a prospective strategy for the speedy and precise detection of MTB., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhu, Feng, Xu, Luo, Zhang, Shi, Wu and Zhang.)

Materials exhibiting ultralong luminescent lifetime show promising applications in the fields of information encryption, sensing, and bioimaging. Herein, we present a low-cost and general strategy to achieve stimulus-responsive ultralong organic phosphorescence (UOP) based on pyrene chromophores doped into polymer matrices. The UOP of the resulted systems presents radiation-, concentration-, time-, and excitation-dependent characteristics. The UOP color can be turned from blue to red by changing the excitation wavelength or the concentration of chromophores. Experimental results prove that these characteristics are attributed to the consumption of triplet oxygen and the different aggregation states of chromophores in the polymer matrices. Finally, we demonstrate that these systems could be applied for multilevel information encryption. This work would promote further development of multi-responsive long-lived luminescent materials., (© 2022 Wiley-VCH GmbH.)