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Sprouts enriched with selenium offer increased nutritional value and chemopreventive properties raising interest in their contribution to the human diet. The effect of selenium depends on its concentration and the chemical forms. The aims of this study were: to synthesize several novel organic selenium compounds (selenoesters), to examine how effectively they can deliver selenium to Brassica sprouts, and investigate their metabolism in sprouts. We revealed that selenium content in the fortified sprouts was several orders of magnitude higher than in the unfortified ones. There were significant differences between doses of selenium delivered to sprouts by different selenium compounds. A small percentage of supplemented selenium (<10%) was incorporated into the sprouts as seleno-L-methionine, Se(IV) and Se-methylselenocysteine, while several other low molecular weight selenium species were also identified, in different proportions, depending on the compound used in the fortification procedure. In conclusion: novel selenorganic compounds were successfully applied to fortify kale sprouts in selenium. The detection, screening, and characterization (including structure elucidation) of their low molecular weight metabolites and derivatives have previously been unreported in Brassica genus.

© 2020 by the authors. Although nickel allergy and carcinogenicity are well known, their molecular mechanisms are still uncertain, thus demanding studies at the molecular level. The nickel carcinogenicity is known to be dependent on the chemical form of nickel, since only certain nickel compounds can enter the cell. This study investigates, for the first time, the cytotoxicity, cellular uptake, and molecular targets of nickel nanoparticles (NiNPs) in human skin cells in comparison with other chemical forms of nickel. The dose-response curve that was obtained for NiNPs in the cytotoxicity assays showed a linear behavior typical of genotoxic carcinogens. The exposure of keratinocytes to NiNPs leads to the release of Ni2+ ions and its accumulation in the cytosol. A 6 kDa nickel-binding molecule was found to be synthesized by cells exposed to NiNPs at a dose corresponding to medium mortality. This molecule was identified to be tumor-related p63-regulated gene 1 protein.

Heat-resistant steels of HP series (Fe-25Cr-35Ni) are used in high temperature structural applications. Their composition include Nb as strong carbide former. Electron Backscatter Diffraction (EBSD) investigations revealed that, in the as-cast condition, alloys exhibit austenitic matrix with intergranular primary carbides such as MC, M23C6 and/or M7C3. During exposure at a high temperature, phase transformations occurred: chromium carbides of M7C3 type transform into the more stable M23C6 type, intergranular M23C6 carbides precipitate, and Lave phase due to increase of Niobium activity with temperature increase, as thermodynamic simulation confirmed. Therefore, combination of EBSD-EDS technique with thermodynamic calculation is one of the novel and most accurate method to investigation of phase transformation, as the precipitations are identified on the basis of their crystal structure, chemical composition and their thermodynamic features.

Heat-resistant steels of HP series (Fe-25Cr-35Ni) are used in high temperature structural applications. Their composition include Nb as strong carbide former. Electron Backscatter Diffraction (EBSD) investigations revealed that, in the as-cast condition, alloys exhibit austenitic matrix with intergranular primary carbides such as MC, M23C6 and/or M7C3. During exposure at a high temperature, phase transformations occurred: chromium carbides of M7C3 type transform into the more stable M23C6 type, intergranular M23C6 carbides precipitate, and Lave phase due to increase of Niobium activity with temperature increase, as thermodynamic simulation confirmed. Therefore, combination of EBSD-EDS technique with thermodynamic calculation is one of the novel and most accurate method to investigation of phase transformation, as the precipitations are identified on the basis of their crystal structure, chemical composition and their thermodynamic features.

Amorphous hydrogenated silicon carbide (a-SiCx:H) coatings were deposited on stainless steel 301 (SS301) using plasma enhanced chemical vapor deposition with the methane gas flow ranging from 30 to 90 sccm. XRD spectra confirmed the amorphous structure of these coatings. The as-deposited coatings all exhibited homogenous dense feature, and no porosities were observed in SEM and AFM analysis. The a-SiCx:H coatings remarkably increased the corrosion resistance of the SS301 substrate. With the increase of the C concentration, the a-SiCx:H coatings exhibited significantly enhanced electrochemical behavior. The a-SiCx:H coating with the highest carbon concentration acted as an excellent barrier to charge transfer, with a corrosion current of 3.5 × 10−12 A/cm2 and a breakdown voltage of 1.36 V, compared to 2.5 × 10−8 A/cm2 and 0.34 V for the SS301 substrate.

The tribocorrosion behavior of titanium-based alloys is of significant interest as bio-implant materials. Bare alloys may not offer enough resistance to tribocorrosion, so coatings could be used to improve their performance. An important biomedical alloy, Ti-13Nb-13Zr, and a newly developed β titanium alloy called "Gum metal" (Ti-23%Ni-0.7%Ta-2%Zr-1 %O2) were used as substrates in the current work. Both were coated with conventional and nano-ceramic materials of Al2O3-TiO2. Bilayered coatings of ZrO2+Al2O3-13%TiO2 were also applied to the Ti-13Nb-13Zr using plasma spray. The coatings on Ti-13Nb-13Zr were applied using plasma spray, whereas that on the Gum metal was applied by a detonation gun (D-Gun). Surface morphology was characterized using a scanning electron microscope (SEM). Tribocorrosion experiments were performed in salt water using a linear reciprocating ball-on-plate tribometer with an aluminum ball as the slider. The nano particles are embedded in the fully melted splats and offered better crack propagation resistance. The high velocity of the D-Gun process resulted in a higher volume fraction of the embedded nano particles and produced substantial improvement in wear resistance relative to the air-plasma-sprayed coating. The conventional coating, with its higher porosity, exhibited a high corrosion rate compared to nano coating. The D-Gun coating, with its lower porosity, had a higher corrosion resistance than the plasma-sprayed coating, but bilayered plasma-sprayed coating showed even higher corrosion resistance, owing to its dense microstructure. Open-circuit potential measurements before and during tribocorrosion showed that the bilayered plasma-sprayed coating had better tribocorrosion resistance than the other coatings. Electrochemical impedance spectroscopy indicate

The phenomenon of variant selection in a bainitic steel containing retained austenite was investigated. The steel was hot-rolled below the Tnr to true strains of epsilon = 0.2 and epsilon = 0.8 in the austenite temperature range. The orientation relationships between bainite and austenite are expressed in Rodrigues space. A strain of 0.2 is shown to be insufficient to induce variant selection. A hot deformation of 0.8 leads to a much smaller number of variants being created, which are shown to be related to the slip systems active during austenite deformation.