WS 2 and MoS 2 inorganic fullerenes (IFs), [1] named after the beautiful hollow molecule C 60 , [2] are close-caged onion-like (i.e., multiwalled) nanoparticles, first produced by the sulfidization of thin films of trioxides. Layered IF compounds, consisting of a sublayer of metal atoms sandwiched between two sublayers of sulfur, are more complex than graphite, even though they share the same space group, P6 3 /mmc.[3] Sheets of graphite and WS 2 (MoS 2 ) can both be wrapped to form nanotubes, [1,4] which exhibit various unique electronic and mechanical properties.[5±9] One of the most promising applications for such WS 2 particles is as an advanced solid-state lubricant in automobile and aerospace industries.[10] After a decade of effort, [11] a large quantity of a new generation of IFs is now achievable, allowing experimental testing of their diverse properties. In this report, dynamic pressure-resistant performance of IF cages is explored using uniaxial shockwave pressures up to 30 GPa. The results reveal, for the first time, that IFs are superb antishock materials with their layered cage-like structure contributing to their excellent shock-absorbing properties. With the majority of these IF nanostructures surviving approx. 25 GPa, it suggests that these IFs are probably the toughest cage molecules now known, and are superior to the all-carbon cage structures (which are collapsed and converted into diamonds under similar or much lower pressures). Accordingly, they offer great potential to withstand very high applied loads when used as lubricants. The WS 2 IF and nanotube sample (I) under a pressure of 9.73 GPa looks identical to the starting material (Fig. 1a), although occasional minimal destruction of the IF was observed. Hence, these WS 2 IFs and nanotubes are resilient to shock pressures of approx. 10 GPa. However, when the shock pressures were increased from 20 to 25 GPa, a range of phenomena was observed for the different samples. Samples (II) and (III) (II: pure WS 2 IFs; III: pure MoS 2 IFs) appeared to outperform sample (I), based on an evaluation of the average degree of destruction that each sample suffered from the shockwaves by transmission electron microscopy (TEM) observation. The mixed phased sample (I) sustained more severe structural damage than the other two samples under similar pressures. About 10±30 % of sample (I) exhibited signs of destruction, either parts of their outer layers had peeled off or the structures had totally collapsed, depending on the applied shock pressures, whereas only 5±10 % of the other two pure IF samples exhibited damage (Figs. 1b±d).X-ray diffraction (XRD) profiles of post-shock samples are presented in Figure 2 along with the starting material to allow comparison. The spectra resemble the major peaks of the starting material (line a), although it is noted that there is a small shift of the (002) peak towards a higher 2h value along with a few intensity variations. It seems that, the higher the shock pressure applied, the larger the detected shift in 2h. To elimi...

Super skinny: TaS2 nanowires with a high aspect ratio (50 000:1; see micrograph) are synthesized from the elements in a one‐step reaction. The single‐crystalline 2H‐TaS2 nanowires are superconducting, with a transition temperature (Tc=3.4 K) that is enhanced compared to that of the bulk material (Tc=0.8 K).

SummaryUltramicrotomy, focused ion beam scanning electron microscopy (FIBSEM) and cryogenic FIBSEM (cryo-FIBSEM) techniques, as developed for the controlled cross-sectioning of mesenchymal stem cells (MSCs) and human osteoblasts (HObs) on titanium (Ti) substrates for transmission electron microscopy (TEM) investigation, are compared. Conventional ultramicrotomy has been used to section cells on Ti-foil substrates embedded in resin, but significant problems with cell detachment using this technique restricted its general applicability. Conventional FIBSEM 'lift-out' procedures were found to be effective for the preparation of uniform sections of fixed and dehydrated cell/Ti specimens, but the control of cell staining remains an issue. Cryo-FIBSEM procedures used with an 'H-bar' sample geometry enabled the sectioning of fixed and hydrated cell/Ti specimens, but issues remain over ion beam-induced artefacts and control of frost on the sample foils.

As the only stable binary compound formed between an alkali metal and nitrogen, lithium nitride possesses remarkable properties and is a model material for energy applications involving the transport of lithium ions. Following a materials design principle drawn from broad structural analogies to hexagonal graphene and boron nitride, we demonstrate that such low dimensional structures can also be formed from an s-block element and nitrogen. Both one- and two-dimensional nanostructures of lithium nitride, Li3N, can be grown despite the absence of an equivalent van der Waals gap. Lithium-ion diffusion is enhanced compared to the bulk compound, yielding materials with exceptional ionic mobility. Li3N demonstrates the conceptual assembly of ionic inorganic nanostructures from monolayers without the requirement of a van der Waals gap. Computational studies reveal an electronic structure mediated by the number of Li-N layers, with a transition from a bulk narrow-bandgap semiconductor to a metal at the nanoscale.

Variations in epidemiological case definitions have major impacts on prevalence of common MSDs. Wide-ranging differences in prevalence may have impacts on purported risk factors that need to be determined.