BiFeO(3) magnetic nanoparticles (BFO MNPs) were prepared with a sol-gel method and characterized as a catalyst. It was found that BFO MNPs effectively catalyzed the decomposition of H(2)O(2) into *OH radicals, being confirmed with electron spin resonance spin-trapping technique and other radical probing techniques. The strong H(2)O(2)-activating ability of BFO MNPs showed promising applications in the oxidative degradation of organic pollutants. When BFO MNPs were used as a heterogeneous Fenton-like catalyst to degrade Rhodamine B, the apparent rate constant for the RhB degradation at 25 degrees C at pH 5.0 in the BFO MNPs-H(2)O(2) system was evaluated to be 2.89 x 10(-2) min(-1), being about 20 folds of that obtained with Fe(3)O(4) MNPs as the catalyst under similar conditions. Moreover, BFO MNPs were demonstrated to have excellent stability and reusability. The catalytic mechanism of BFO MNPs was also investigated with Monte Carlo simulations and density functional theory calculations.

The clinical picture of severe acute respiratory syndrome (SARS) is characterized by an over-exuberant immune response with lung lymphomononuclear cells infilteration and proliferation that may account for tissue damage more than the direct effect of viral replication. To understand how cells response in the early stage of virus-host cell interaction, in this study, a purified recombinant S protein was studied for stimulating murine macrophages (RAW264.7) to produce proinflammatory cytokines (IL-6 and TNF-alpha) and chemokine IL-8. We found that direct induction of IL-6 and TNF-alpha release in the supernatant in a dose-, time-dependent manner and highly spike protein-specific, but no induction of IL-8 was detected. Further experiments showed that IL-6 and TNF-alpha production were dependent on NF-kappaB, which was activated through I-kappaBalpha degradation. These results suggest that SARS-CoV spike protein may play an important role in the pathogenesis of SARS, especially in inflammation and high fever.

High-performance supercapacitors (SCs) are promising energy storage devices to meet the pressing demand for future wearable applications. Because the surface area of a human body is limited to 2 m , the key challenge in this field is how to realize a high areal capacitance for SCs, while achieving rapid charging, good capacitive retention, flexibility, and waterproofing. To address this challenge, low-cost materials are used including multiwall carbon nanotube (MWCNT), reduced graphene oxide (RGO), and metallic textiles to fabricate composite fabric electrodes, in which MWCNT and RGO are alternatively vacuum-filtrated directly onto Ni-coated cotton fabrics. The composite fabric electrodes display typical electrical double layer capacitor behavior, and reach an ultrahigh areal capacitance up to 6.2 F cm at a high areal current density of 20 mA cm . All-solid-state fabric-type SC devices made with the composite fabric electrodes and water-repellent treatment can reach record-breaking performance of 2.7 F cm at 20 mA cm at the first charge-discharge cycle, 3.2 F cm after 10 000 charge-discharge cycles, zero capacitive decay after 10 000 bending tests, and 10 h continuous underwater operation. The SC devices are easy to assemble into tandem structures and integrate into garments by simple sewing.

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Solar-driven reduction of CO , which converts inexhaustible solar energy into value-added fuels, has been recognized as a promising sustainable energy conversion technology. However, the overall conversion efficiency is significantly limited by the inefficient charge separation and sluggish interfacial reaction dynamics, which resulted from a lack of sufficient active sites. Herein, Bi O Cl superfine nanotubes with a bilayer thickness of the tube wall are designed to achieve structural distortion for the creation of surface oxygen defects, thus accelerating the carrier migration and facilitating CO activation. Without cocatalyst and sacrificing reagent, Bi O Cl nanotubes deliver high selectivity CO evolution rate of 48.6 μmol g h in water (16.8 times than of bulk Bi O Cl ), while maintaining stability even after 12 h of testing. This paves the way to design efficient photocatalysts with collaborative optimizing charge separation and CO activation towards CO photoreduction.

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Effects of chelating agents on the catalytic degradation of bisphenol A (BPA) was studied in the presence of BiFeO3 nanoparticles as a heterogeneous catalyst and H2O2 as a green oxidant. The oxidizing ability of H2O2 in the presence of nano-BiFeO3 alone was not so strong to degrade BPA at neutral pH values, due to the limited catalytic ability of nano-BiFeO3. Once the surface of nano-BiFeO3 was in situ modified by adding proper organic ligands, the BPA degradation was much accelerated in the pH range of 5–9. The enhancing effect of the ligand was observed to have an order of blank < tartaric acid < formic acid < glycine < nitrilotriacetic acid < ethylenediaminetetraacetic acid (EDTA). The addition of 0.25 mmol L–1 EDTA in the H2O2–BiFeO3 system at pH 5.0 and 30 °C increased the BPA removal from 20.4% to 91.2% with reaction time of 120 min. The enhancing effect of the ligand was found to be indifferent of the possible dissolution of iron from nano-BiFeO3, but correlated well with the accelerated •OH formation from the H2O2 decomposition at the BiFeO3 surface, which was confirmed by ESR measurements and density functional theory studies. In general, more addition of EDTA, higher H2O2 concentrations, or higher temperatures were favorable to the BPA degradation. The effect of the EDTA addition on the kinetics of BPA degradation was also clarified.

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