Nickel nanoparticles (Ni-NPs) with controlled size and narrow size distribution were successfully prepared in spherical poly (acrylic acid) (PAA) brushes (SPBs). The brushes act as nanoreactors for generating the Ni-NPs via adsorption of nickel ions in the brushes and subsequent reduction by addition of NaBH4. The size of Ni-NPs can be well-controlled in several nanometers and with narrow size-distribution. Most interestingly, the size can be tuned by the reaction temperature: the average size increased from 3 to 7 nm upon increasing the reaction temperature from 273 to 303 K. The catalytic activity of these Ni-NPs trapped in SPBs were evaluated using a model reaction based on the reduction of 4-nitrophenol to 4-aminophenol by NaBH4. The kinetic data were observed to follow the pseudofirst-order rate law, and the apparent rate constant was linearly dependent on the total surface area of the Ni-NPs and the reaction temperatures. This work opens a new way to prepare well-controlled Ni-NPs which should be ideal candidates for catalysts with high performance.

We present a green and scalable route toward the formation of reduced graphene oxide (r-GO) by photothermal reduction induced by infrared (IR) irradiation, utilizing a bathroom IR lamp as the source of IR light. Thermogravimetric analysis, Raman, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the reduction of r-GO by IR light. Ultraviolet-visible-infrared spectra indicate that adsorption of IR light by original GO films is less than that of UV and visible light; but when GO is exposed to IR light, its adsorption of IR light increases very rapidly with time. The influence of the power density of the IR light on the structure and properties of r-GO was investigated. At high IR power density, the reduction reaction was so fierce that r-GO became highly porous due to the rapid degassing and exfoliation of GO sheets. The r-GO powder revealed good performance as the anode material for lithium ion batteries. At relatively low IR power density, the reduction process was found to be mild but relatively slow. Crack-free and uniform conductive r-GO thin films with a volume conductivity of 1670 S m(-1) were then prepared by two-step IR irradiation, i.e. first at low IR power density and then at high IR power density. Moreover, the r-GO films were also observed to exhibit obvious and reversible IR light-sensing behavior.

Hesperidin could alleviate H1N1-induced impairment of pulmonary function by inhibiting cytokine production in pulmonary microvascular endothelial cells through MAPK signalling pathways.

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