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This article studies the role of electrochemical parameters in controlling the morphology of oxidized TiO2 nanotubes and the electrochemical performance of modified TiO2 nanotubes. Humidity is a key factor for fabricating TiO2 nanotubes. When the relative humidity belows 70%, the TiO2 nanotubes can be successfully prepared. What's more, by changing the anodization voltage and time, the diameter and the length of TiO2 nanotubes can be adjusted. In addition, the TiO2 nanotubes are modified through electrochemical self-doping and loading Pt metal particles on the surface of the nanotubes, which promotes the performance of the supercapacitor. The sample anodized at 100 V for 3 h has a specific capacity of up to 2.576 mF/cm² at a scan rate of 100 mV/s after self-doping, and its capacity retention rate still remains at 89.55% after 5 000 cycles, demonstrating excellent cycling stability. The Pt-modified sample has a specific capacity of up to 3.486 mF/cm² at the same scan rate, exhibiting more outstanding electrochemical performance. [ABSTRACT FROM AUTHOR]

We describe the case of a 57-year-old male with jaundice, abdominal distension and fatigue. He was diagnosed as chronic active Epstein-Barr virus infection (CAEBV) due to intermittent elevated liver enzymes, hepatosplenomegaly and pancytopenia, with persistent positive of EBV biomarkers in blood and also positive in liver tissue. The patient was reinfected by SARS-CoV-2 within 2 months companied with CAEBV. The patient's second infection with SARS-CoV-2 led to the aggravated liver dysfunction with pneumonia and re-admission. After receiving symptomatic treatment, the patient showed significantly improvement of symptoms with partially restoration of liver function. After discharge, the patient's health status continued to deteriorate and eventually died. The instances of SARS-CoV-2 co-infection with the original chronic virus are not uncommon, but the exact mechanism of EBV and SARS-CoV-2 coinfection and the relationship between them are still unclear. Since co-infection of SARS-CoV-2 with original chronic virus might affect each other and lead disease aggravated and complicated, it is necessary to differentiate in the diagnosis of disease and it is important to be aware of the re-infection signs of SARS-CoV-2 in people with chronic virus infection diseases, as well as the risk of co-infection of SARS-CoV-2 with other viruses. [ABSTRACT FROM AUTHOR]

The surface plasmon resonance (SPR)‐generated electric field (E‐field) intensities around a Ag nanocube (NC) before and after it is covered by a BaTiO3 (BTO) layer (BTO@Ag NC) were calculated. It was observed that the theoretical E‐field intensities were reduced on BTO@Ag NCs, thus suggesting inferior catalytic activities under visible light illumination. However, BTO@Ag NCs experimentally displayed better photocatalytic performance than that of Ag NCs under illumination at 633 nm, both in ambient argon (Ar) and in ambient air, where p‐aminothiophenol (PATP) molecules were used to probe the conversion. The mechanism can be attributed to the surface polarization of the BTO layer trigged by a SPR effect of the Ag core. The oscillation of free electrons in the Ag core aroused appearance of surface polarization charge on the ferroelectric (FE) BTO surface, which resulted in the enhanced catalytic properties of BTO@Ag NCs. Therefore, our finding may provide a novel method to enhance visible‐light responsive photocatalytic activity of wide bandgap FE materials by depositing them on plasmonic metal nanostructures. [ABSTRACT FROM AUTHOR]

Among the electrode materials for supercapacitors (SCs), metal-organic framework (MOFs) is attracting huge research interest as a new type of energy storage electrode materia. However, due to their poor conductivity and stability, the practical application of original MOFs in the field of energy storage has been greatly hindered. Here, we demonstrate a special core-shell structure, which the synergistic action of NiCo2O4 and Ni-MOF forms a tight conductive network that speeds up electron transport and larger specific surface area, more active sites were obtained and mechanical stability that indicates its outstanding long life. The test results show that it has a high specific capacity of 4.23 F cm–2 at 5 mA cm–2, and the capacity retention rate is maintained at 97.5% after 8000 cycles. In addition, an asymmetric supercapacitor device, using NiCo2O4@Ni-MOF and activated carbon (AC) as anode and cathode, has a high specific capacity of 3.21 F cm–2 at 5 mA cm–2 and excellent cycling performance (83.8% retention over 8000 cycles at 10 mA cm–2). Our work demonstrates the possibility of using novel structured Ni-MOF-based hybrid arrays as electrodes for SCs with enhanced electrochemical performance compared to Ni-MOF and NiCo2O4, providing a reliable prospect for flexible energy storage devices. [ABSTRACT FROM AUTHOR]

Phase change materials can enable temperature self-regulation due to their drastic changes in optical properties accompanying the phase transition. Significant reduction of the optical absorption after the transition is the key ingredient for an enhanced regulating performance. However, the absorptivity of unpatterned vanadium dioxide (VO2) thin films can hardly be reduced after phase transition at visual-to-infrared band. In this work, we combine the direct binary search (DBS) and particle swarm optimization (PSO) algorithms for an optimized design of temperature self-regulating nano-photonic devices on VO2 thin films. For a given incident wavelength, a pixelated structure is firstly inverse-designed by the DBS algorithm which maximizes the absorption contrast before and after the transition. To overcome fabrication challenges as pixel size is at deep sub-wavelength scale, the pixelated structure can then be replaced by geometric shapes which are more tractable in manufacturing processes. The geometrical parameters are optimized by the PSO algorithm where our optimized device brings the absorptivity down to 33% after the transition. These results provide an effective way for the inverse design of optimized nano-photonic structures based on phase change materials. [ABSTRACT FROM AUTHOR]