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High strength and high ductility are often mutually exclusive properties for structural metallic materials. This is particularly important for aluminum (Al)-based alloys which are widely commercially employed. Here, we introduce a hierarchical nanostructured Al alloy with a structure of Al nanograins surrounded by nano-sized metallic glass (MG) shells. It achieves an ultrahigh yield strength of 1.2 GPa in tension (1.7 GPa in compression) along with 15% plasticity in tension (over 70% in compression). The nano-sized MG phase facilitates such ultrahigh strength by impeding dislocation gliding from one nanograin to another, while continuous generation-movement-annihilation of dislocations in the Al nanograins and the flow behavior of the nano-sized MG phase result in increased plasticity. This plastic deformation mechanism is also an efficient way to decrease grain size to sub-10 nm size for low melting temperature metals like Al, making this structural design one solution to the strength-plasticity trade-off.

Water electrolysis is the key to a decarbonized energy system, as it enables the conversion and storage of renewably generated intermittent electricity in the form of hydrogen. However, reliability challenges arising from titanium‐based porous transport layers (PTLs) have hitherto restricted the deployment of next‐generation water‐splitting devices. Here, it is shown for the first time how PTLs can be adapted so that their interface remains well protected and resistant to corrosion across ≈4000 h under real electrolysis conditions. It is also demonstrated that the malfunctioning of unprotected PTLs is a result triggered by additional fatal degradation mechanisms over the anodic catalyst layer beyond the impacts expected from iridium oxide stability. Now, superior durability and efficiency in water electrolyzers can be achieved over extended periods of operation with less‐expensive PTLs with proper protection, which can be explained by the detailed reconstruction of the interface between the different elements, materials, layers, and components presented in this work.

Background A novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), which causing the pandemic of coronavirus disease 2019 (COVID‐19), may attack testes by angiotensin‐converting enzyme 2. Objective To assess whether SARS‐CoV‐2 infection can affect sex‐related hormones and testicular function in recovering patients. Materials and methods The patients were separately classified according to the duration of viral shedding (long‐term positive vs normal‐term group, with the former cases having a duration > 50 days) and disease severity (moderate vs severe group). Differences in sex‐related hormone levels were compared between groups and linear regression analysis was used to compare the associations of testosterone (T) and estradiol with various clinical and laboratory factors. Results A total of 39 COVID‐19‐infected patients were included in this study. The mean T level was in the normal reference range while the mean estradiol level was above the normal limit. There were no significant differences between the long‐term positive and normal‐term groups in T (P = .964), follicle‐stimulating hormone (FSH; P = .694), luteinizing hormone (LH; P = .171), prolactin (PRL; P = .836), or T/LH (P = .512). However, estradiol was higher in the normal‐term group than the long‐term positive group (P < .001). Moreover, there were also no significant differences between the moderate and severe groups in sex‐related hormones, duration of viral shedding, or serum biochemical or inflammation indicators. Additionally, regression analyses showed that there were no associations between the T level and the clinical and laboratory factors, while estradiol was negatively associated with the duration of viral shedding. Conclusion In males infected with SARS‐CoV‐2, most sex‐related hormones (T, FSH and LH levels) remain within the normal reference ranges after recovery from COVID‐19, and no significant associations were observed between T level and disease duration or severity. At present, there is insufficient evidence to show that SARS‐CoV‐2 causes hypogonadism and sterility, but the potential risk should not be ignored.

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The cell performance and durability of polymer electrolyte membrane (PEM) water electrolyzers are limited by the surface passivation of titanium-based porous transport layers (PTLs). In order to ensure stable performance profiles over time, large amounts (≥1 mg•cm −2 ) of noble metals (Au, Pt, Ir) are most widely used to coat titanium-based PTLs. However, their high cost is still a major obstacle toward commercialization and widespread application. In this paper, we assess different loadings of iridium, ranging from 0.005 to 0.05 mg•cm −2 in titanium PTLs, that consequently affect the investment costs of PEM water electrolyzers. Concerning a reduction in the precious metal costs, we found that Ir as a protective layer with a loading of 0.025 mg• cm −2 on the PTLs would be sufficient to achieve the same cell performance as PTLs with a higher Ir loading. This Ir loading is a 40-fold reduction over the Au or Pt loading typically used for protective layers in current commercial PEM water electrolyzers. We show that the Ir protective layer here not only decreases the Ohmic resistance significantly, which is the largest part of the gain in performance, but moreover, the oxygen evolution reaction activity of the iridium layer makes it promising as a cost-effective catalyst layer. Our work also confirms that the proper construction of a multifunctional interface between a membrane and a PTL indeed plays a crucial role in guaranteeing the superior performance and efficiency of electrochemical devices.

High‐entropy alloys (HEAs) and metallic glasses (MGs) are two material classes based on the massive mixing of multiple‐principal elements. HEAs are single or multiphase crystalline solid solutions with high ductility. MGs with amorphous structure have superior strength but usually poor ductility. Here, the stacking fault energy in the high‐entropy nanotwinned crystalline phase and the glass‐forming‐ability in the MG phase of the same material are controlled, realizing a novel nanocomposite with near theoretical yield strength (G/24, where G is the shear modulus of a material) and homogeneous plastic strain above 45% in compression. The mutually compatible flow behavior of the MG phase and the dislocation flux in the crystals enable homogeneous plastic co‐deformation of the two regions. This crystal–glass high‐entropy nanocomposite design concept provides a new approach to developing advanced materials with an outstanding combination of strength and ductility.

Transportation is an important factor that affects energy consumption, and driving behavior is one of the main factors affecting vehicle fuel consumption. The purpose of this paper is to improve fuel consumption monitoring databases based on mobile phone data. Based on the mobile phone terminals and on-board diagnostic system (OBD) installed in taxis, driving behavior data and fuel consumption data are extracted, respectively. By matching the driving behavior data collected by a mobile phone with the fuel consumption data collected by OBD, the correlation between driving behavior and fuel consumption is explored, so that vehicle fuel consumption could be predicted based on mobile phone data. The fuel consumption prediction models are built using back propagation (BP) neural network, support vector regression (SVR), and random forests. The results show that the average speed, average speed except for idle (ASEI), average acceleration, average deceleration, acceleration time percentage, deceleration time percentage, and cruising time percentage are important indicators for fuel consumption evaluation. All three models could predict fuel consumption accurately, with an absolute relative error less than 10%. The random forest model is proved to have the highest accuracy and runs faster, making it suitable for wide application. This method lays a foundation for monitoring database improvement and fine management of urban transportation fuel consumption.