Biodegradation and Mechanical Integrity of Magnesium and Magnesium Alloys Suitable for Implants

This book chapter deals with the fundamental aspects of corrosion of magnesium based alloys in bodily fluids and reviews the various techniques that can be used to tune their degradation rate. The time-dependent evolution of their mechanical properties during the biodegradation process is also outlined

White-light photoluminescence and photoactivation in cadmium sulfide embedded in mesoporous silicon dioxide templates studied by confocal laser scanning microscopy

This is the author's version of a work that was accepted for publication in Journal of colloid and interface science. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of colloid and interface science, [147, 1, (2013)] DOI10.1016/j.jcis.2013.06.022)SBA-15 and SBA-16 silica templates have been infiltrated with CdS by means of nanocasting using a hybrid precursor. The morphology and structure of both the SiO2@CdS nanocomposites and the silica-free CdS replicas have been characterized. The three-dimensional nanocrystalline CdS networks embedded in SBA-15 and SBA-16 silica templates exhibit broad photoluminescence (PL) spectra over the entire visible range, together with enhanced PL intensity compared to silica-free CdS replicas. These effects result from the role silica plays in passivating the surface of the CdS mesostructures. Furthermore, photoactivation is eventually observed during continuous illumination because of both structural and chemical surface odifications. Owing to this combination of properties, these materials could be appealing for solid-state lighting, where ultra-bright near-white PL emission is indispensable

Spread of a SARS-CoV-2 variant through Europe in the summer of 2020.

Following its emergence in late 2019, the spread of SARS-CoV-21,2 has been tracked by phylogenetic analysis of viral genome sequences in unprecedented detail3–5. Although the virus spread globally in early 2020 before borders closed, intercontinental travel has since been greatly reduced. However, travel within Europe resumed in the summer of 2020. Here we report on a SARS-CoV-2 variant, 20E (EU1), that was identified in Spain in early summer 2020 and subsequently spread across Europe. We find no evidence that this variant has increased transmissibility, but instead demonstrate how rising incidence in Spain, resumption of travel, and lack of effective screening and containment may explain the variant’s success. Despite travel restrictions, we estimate that 20E (EU1) was introduced hundreds of times to European countries by summertime travellers, which is likely to have undermined local efforts to minimize infection with SARS-CoV-2. Our results illustrate how a variant can rapidly become dominant even in the absence of a substantial transmission advantage in favourable epidemiological settings. Genomic surveillance is critical for understanding how travel can affect transmission of SARS-CoV-2, and thus for informing future containment strategies as travel resumes. © 2021, The Author(s), under exclusive licence to Springer Nature Limited

An examination of microtexture and microstructure in ultrafine-grained nickel

Rev.Adv.Mater.Sci. 7(2004) 41-49A detailed orientation imaging microscopy (OIM) investigation was conducted to evaluate the microstructural characteristics in samples of pure nickel processed using three different procedures of severe plastic deformation (SPD): equal-channel angular pressing (ECAP), highpressure torsion (HPT) and a combination of ECAP and HPT. Electron backscattering diffraction (EBSD) techniques were employed to measure the microtextures and the distributions of the misorientation angles. A thorough analysis of the microtexture revealed the shear plane normal and shear direction for UFG nickel obtained by various kinds of severe plastic deformation. It is shown that a combination of ECAP and HPT leads both to a greater refinement in the microstructure and to a smaller fraction of boundaries having low angles of misorientation

Orientation imaging microscopy of ultrafine-grained nickel

Orientation imagining microscopy was used to measure the distributions of grain boundary misorientations in ultrafine-grained nickel processed by high-pressure torsion and equal-channel angular pressing. Both procedures give high fractions of high-angle boundaries but also higher fractions of low-angle boundaries than anticipated from a random distribution

Hydrogen sorption properties of the NaBH4 – MgH2 system: kinetic and thermodynamic studies

The hydrogen sorption properties of the NaBH4 – MgH2 system (2:1 and 1:2 molar ratio) as obtained by manometric and calorimetric measurements are presented. The kinetic and thermodynamic features are discussed