Penetration study of formulated nanosized titanium dioxide in models of damaged and sun-irradiated skins.

Inorganic ultraviolet filters such as titanium dioxide (TiO(2)), safe to use on healthy skin, are often applied on compromised and irradiated skin. The aim of this study was to evaluate in vitro the cutaneous penetration of TiO(2) nanoparticles (≥20 nm primary size), included in a sunscreen, in intact, damaged, irradiated, and damaged/irradiated pigskin. Cutaneous penetration and localization of TiO(2) after a 24-h sunscreen application were investigated quantitatively using inductively coupled plasma-mass spectrometry, and qualitatively using transmission electron microscopy (TEM).

Surfactant-free CZTS nanoparticles as building blocks for low-cost solar cell absorbers.

A process route for the fabrication of solvent-redispersible, surfactant-free Cu₂ZnSnS₄ (CZTS) nanoparticles has been designed with the objective to have the benefit of a simple sulfide source which advantageously acts as (i) a complexing agent inhibiting crystallite growth, (ii) a surface additive providing redispersion in low ionic strength polar solvents and (iii) a transient ligand easily replaced by an carbon-free surface additive. This multifunctional use of the sulfide source has been achieved through a fine tuning of ((Cu²⁺)(a)(Zn²⁺)(b)(Sn⁴⁺)(c)(Tu)(d)(OH⁻)(e))(t⁺), Tu = thiourea) oligomers, leading after temperature polycondensation and S²⁻ exchange to highly concentrated (c > 100 g l⁻¹), stable, ethanolic CZTS dispersions. The good electronic properties and low-defect concentration of the sintered, crack-free CZTSe films resulting from these building blocks was shown by photoluminescence investigation, making these building blocks interesting for low-cost, high-performance CZTSe solar cells.

Controlled growth of CNT in mesoporous AAO through optimized conditions for membrane preparation and CVD operation.

Anodic aluminium oxide (RAAO) membranes with a mesoporous structure were prepared under strictly controlling experimental process conditions, and physically and chemically characterized by a wide range of experimental techniques. Commercial anodic aluminium oxide (CAAO) membranes were also investigated for comparison. We demonstrated that RAAO membranes have lower content of both water and phosphorus and showed better porosity shape than CAAO.

Transmission electron microscopy for elucidating the impact of silver-based treatments (ionic silver versus nanosilver-containing coating) on the model yeast Saccharomyces cerevisiae.

After exposure to ionic silver or nanosilver-containing plasma coating, the same visual aspect of scanning transmission electron microscopy (STEM) images was observed for the model yeast Saccharomyces cerevisiae. The main common feature was the presence of electron-dense nodules all over the cell. However, high resolution TEM (HRTEM), STEM, energy dispersive x-ray microanalysis spectroscopy (EDS) and electron microdiffraction revealed some striking differences.