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This work systematically studied the corrosion behavior and passivation property of CoCrFeNi high‐entropy alloys (HEAs) in a simulated seawater environment. The results reveal that the addition of CO32−/HCO3− results in the secondary passivation of the HEA in NaCl solution, and secondary passivation film possesses higher dissolution rate in comparison with primary passive film. H+ ions ionized by HCO3− facilitate the charge transfer process, thin the thickness of passive film, and increase the disordered degree of the film. Moreover, the presence of HCO3− promotes the nucleation and growth of metastable pits, and enhances the pitting sensitivity. Furthermore, an increase in CO32− concentration accelerates the dissolution of passive film, weakens the compactness and protective performance of the film, and increases the probability that metastable pitting evolves into stable pitting, as well aggravates the corrosion of the HEA. In addition, the corrosion resistance of the HEA is diminished due to the formation of microgalvanic corrosion cells between matrix and inclusion. The selective dissolution of elements occurred in the HEA. [ABSTRACT FROM AUTHOR]

The effect of different annealing temperatures on the corrosion behavior of CoCrNi medium entropy alloy (MEA) was investigated in an alkaline soil simulation solution. The results show the corrosion resistance of the MEA gradually increases with increasing annealing temperature. The corrosion behavior of the MEA is correlated with grain size, oxide inclusions, and surface passive film. With an increasing grain size, the proportion of grain boundaries decreases, which improves its corrosion resistance. The micro‐galvanic corrosion cell exists between the oxide and its surrounding matrix, which promotes the occurrence of pitting corrosion. As the annealing temperature increases, the film formed on the MEA surface becomes more complete and dense, greatly increasing the corrosion resistance of the MEA. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) fabricated with a low‐temperature (≤150 °C) SnO2‐based electron transport layer (ETL) have been rapidly developing and demonstrate high power conversion efficiency (PCE). To further enhance the efficiency and stability of PSCs, high‐quality perovskite and SnO2 films are needed, and the interfacial performance between the SnO2 ETL and the perovskite layer needs to be improved. In this work, potassium p‐aminobenzoate (KPAB) was introduced to regulate the SnO2 ETL to obtain reduced defects and an excellent wetting property, inducing vertically aligned crystal growth of the perovskites on the interface side of the SnO2 ETL. In addition, the potassium ions were able to interact with the halogen ions of the perovskite, which further enhanced the quality of the perovskite film. Due to the abovementioned strengths of KPAB, we demonstrated that devices based on KPAB‐SnO2 have a higher power conversion efficiency (19.03 %), better reproducibility, and superior operational stability compared to devices with pristine SnO2. [ABSTRACT FROM AUTHOR]

To overcome two main drawbacks of SnO2 as anode material in lithium‐ion batteries, low conductivity and poor cycling stability, SnO2/Sn@TiO2@C composite is prepared via one‐pot hydrothermal reaction to synthesize SnO2/C precursor‐assembled hollow nanospheres and then coated with TiO2 and resorcinol‐formaldehyde resin. After calcination, multi‐shelled hollow nanospheres of SnO2/Sn@TiO2@C are formed. When used as anode material in lithium‐ion batteries, the as‐prepared composite exhibits high discharge capacity of 1565 mAh g−1 at 0.5 A g−1. After 300 cycles at 1 A g−1, the discharge capacity still reaches 961 mAh g−1 with capacity fading rate of just 0.11 % per cycle. The average discharge capacity reaches 395 mAh g−1 even at 5 A g−1. The superior lithium storage performance mainly benefits from the unique multi‐shelled hollow nanosphere structure. The coating TiO2 and amorphous carbon increase structural and cycling stabilities of SnO2/Sn hollow nanospheres. The outermost carbon shell further enhances electronic conductivity of the composite. The hollow nanosphere structure also endows SnO2/Sn nanoparticles with high electrochemical activity. This work proposes a feasible synthesis and structure design strategy for the development of advanced SnO2‐based composite materials. [ABSTRACT FROM AUTHOR]

This work systematically studied the corrosion behavior and passivation property of CoCrFeNi high‐entropy alloys (HEAs) in a simulated seawater environment. The results reveal that the addition of CO32−/HCO3− results in the secondary passivation of the HEA in NaCl solution, and secondary passivation film possesses higher dissolution rate in comparison with primary passive film. H+ ions ionized by HCO3− facilitate the charge transfer process, thin the thickness of passive film, and increase the disordered degree of the film. Moreover, the presence of HCO3− promotes the nucleation and growth of metastable pits, and enhances the pitting sensitivity. Furthermore, an increase in CO32− concentration accelerates the dissolution of passive film, weakens the compactness and protective performance of the film, and increases the probability that metastable pitting evolves into stable pitting, as well aggravates the corrosion of the HEA. In addition, the corrosion resistance of the HEA is diminished due to the formation of microgalvanic corrosion cells between matrix and inclusion. The selective dissolution of elements occurred in the HEA. [ABSTRACT FROM AUTHOR]

To predict the safety of a drug at an early stage in its development is a major challenge as there is a lack of in vitro heart models that correlate data from preclinical toxicity screening assays with clinical results. A biophysically detailed computer model of the heart, the virtual heart, provides a powerful tool for simulating drug-ion channel interactions and cardiac functions during normal and disease conditions and, therefore, provides a powerful platform for drug cardiotoxicity screening. In this article, we first review recent progress in the development of theory on drug-ion channel interactions and mathematical modelling. Then we propose a family of biomarkers that can quantitatively characterize the actions of a drug on the electrical activity of the heart at multi-physical scales including cellular and tissue levels. We also conducted some simulations to demonstrate the application of the virtual heart to assess the pro-arrhythmic effects of cisapride and amiodarone. Using the model we investigated the mechanisms responsible for the differences between the two drugs on pro-arrhythmogenesis, even though both prolong the QT interval of ECGs. Several challenges for further development of a virtual heart as a platform for screening drug cardiotoxicity are discussed. [ABSTRACT FROM AUTHOR]