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The first Arctic intercomparison of three solar ultraviolet (UV) spectroradiometers and two multifilter radiometers was held in May and June 2009 at Ny-Å lesund, Svalbard, Norway. The transportable reference spectroradiometer QASUME acted as reference instrument for this intercomparison. The measurement period extended over eleven days, comprising clear sky and overcast weather conditions. Due to the high latitude, measurements could be performed throughout the day during this period. The intercomparison demonstrated that the solar UV measurements from all instruments agreed to within ±15% during the whole measurement period, while the spectroradiometer from the Alfred-Wegener Institute agreed to better than ±5%. This intercomparison has demonstrated that solar UV measurements can be performed reliably in the high-latitude Arctic environment with uncertainties comparable to mid-latitude sites.

Ge-rich Ge–Sb–Te compounds are attractive materials for future phase change memories due to their greater crystallization temperature as it provides a wide range of applications. Herein, we report the self-assembled Ge-rich Ge–Sb–Te/Sb2Te3 core-shell nanowires grown by metal-organic chemical vapor deposition. The core Ge-rich Ge–Sb–Te nanowires were self-assembled through the vapor–liquid–solid mechanism, catalyzed by Au nanoparticles on Si (100) and SiO2/Si substrates; conformal overgrowth of the Sb2Te3 shell was subsequently performed at room temperature to realize the core-shell heterostructures. Both Ge-rich Ge–Sb–Te core and Ge-rich Ge–Sb–Te/Sb2Te3 core-shell nanowires were extensively characterized by means of scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction, Raman microspectroscopy, and electron energy loss spectroscopy to analyze the surface morphology, crystalline structure, vibrational properties, and elemental composition.

Background. New antiviral textiles for the protection and prevention of life-threatening viral diseases are needed. Graphene oxide derivatives are versatile substances that can be combined with fabrics by different green electrochemistry methods. Methods In this study, graphene oxide (GO) nanosheets were combined with textile samples to study GO antiviral potential. GO synthesized in the Chemistry laboratories at the University of Rome Tor Vergata (Italy) and characterized with TEM/EDX, XRD, TGA, Raman spectroscopy, and FTIR, was applied at three different concentrations to linen textiles with the hot-dip and dry method to obtain filters. The GO-treated textiles were tested to prevent infection of a human glioblastoma cell line (U373) with human herpesvirus 6A (HHV-6A). Green electrochemical exfoliation of graphite into the oxidized graphene nanosheets provides a final GO-based product suitable for a virus interaction, mainly depending on the double layer of nanosheets, their corresponding nanometric sizes, and Z-potential value. Results Since GO-treated filters were able to prevent infection of cells in a dose-dependent fashion, our results suggest that GO may exert antiviral properties that can be exploited for medical devices and general use fabrics.