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Thermally sprayed Al and Al/SiC composite coatings have been deposited on pure magnesium and their corrosion behaviour in 3.5 wt.% NaCl solution has been studied. Al/SiC composite coatings were fabricated with 9 vol.% reinforcement percentage and with porosities around 3.5%, while the porosity of the as-sprayed pure Al coatings was in the range 2.4 vol.% to 4.4 vol.% and depended more on the spraying distance and numbers of layers deposited. A mechanical compaction was applied to the coatings at room temperature and coatings that were nearly free from pores were fabricated for the Al and Al/SiC coatings. In the electrochemical tests, all the coatings showed higher corrosion potentials (about of 200 mV) than uncoated substrates while current densities were nearly two orders of magnitude lower for the Al/SiC composite coatings and three orders of magnitude lower for the pure aluminium coatings. This protective effect was even better in the compacted coatings, currents densities were between five or six orders of magnitude lower than that of uncoated magnesium.

Silica mono-and multilayered coatings have been obtained through a sol–gel route on aluminium matrix composites reinforced with SiC particles for their corrosion protection. Tetraethoxysilane (TEOS) was used as alcoxide precursor, and dip-coating technique of the samples was used at different extraction rates. Corrosion protection of the different coating systems have been evaluated in 3.5 wt.% NaCl at different immersion times using several electrochemical techniques including linear polarization resistance, anodic–cathodic polarization, and electrochemical impedance spectroscopy. Gravimetric tests have been also used to characterize the protective effectiveness of the coatings, using low angle X-ray diffraction to identify the corrosion products. Coatings characterization before and after corrosion tests have been carried out using Scanning Electron Microscopy and Atomic Force Microscopy, studying the mechanisms of corrosion that take part in coated and uncoated composites. A corrosion mechanism for each one of the tested materials has been proposed.

Sol–gel silica coatings have been developed, using a dip-coating process to provide corrosion and wear resistance to aluminium composites reinforced with SiC particles. Pin-on-disk tests indicate that these ceramic coatings reduce the adhesive wear between the steel pin and composite. The coatings extracted at lower deposition speeds are thinner than those extracted at faster speeds, but they show better wear resistance which can be explained by their greater hardness caused by a better consolidated structure.

Silica coatings up to 20 μm thick have been obtained through a sol–gel route on aluminium matrix composites reinforced with SiC particles. Single silica layer and multiple ones have been deposited on the substrates and extensive crack-free surfaces have been achieved with both methods. The topography of the layers has been characterised by means of Scanning Electronic Microscopy and Atomic Force Microscopy, and dense flat surface has been observed. However, topographical details consisting of spherical zones tend to appear on the surface of multilayered coatings. The mechanical properties of the different coatings have been measured using the nanoindentation technique independently from the substrate underneath, and hardness and elastic modulus similar and even higher than those of fused silica have been obtained for sol–gel multilayered coatings. The microstructure of the coatings has been studied by Transmission Electronic Microscopy, and the appearance of nanocrystals on the flat surfaces has been considered responsible of the mechanical properties measured.

Nitric oxide (NO) is a signal molecule with functions such as neurotransmission, local vascular relaxation, and anti-inflammation in many physiological and pathological processes. Various factors regulate its intracellular lifetime. Due to its high reactivity in biological systems, it is transformed in the bloodstream into nitrates (NO − 3 ) by oxyhemoglobin. The Griess reaction is a technically simple method (spectrophotometric, 540 nm) for the analysis of nitrites (NO − 2 ) in aqueous solutions. We studied the interference of common anticoagulants in the quantification of nitrate and nitrite in plasma samples by the Griess method. We obtained rat plasma using heparin or sodium EDTA as anticoagulants, then added, or otherwise, known NO − 3 amounts in order to calculate their recovery. We also studied the effect of ultra-filtration performed before Griess reaction on plasma and aqueous solutions of various anticoagulants (heparin, EDTA, and also sodium citrate) to compare the recoveries of added NO − 3 or NO − 2 . We used standards of NO − 3 or NO − 2 for quantification. We conclude that: (i) The bacterial nitrate reductase used to reduce NO − 3 to NO − 2 is unstable in certain storage conditions and interferes with different volumes of plasma used. (ii) The ultrafiltration (which is sometimes performed before the Griess reaction) of plasma obtained with EDTA or citrate is not recommended because it leads to overestimation of NO − 3 . In contrast, ultrafiltration is necessary when heparin is used. (iii) The absorbance at 540 nm attributed to plasma itself (basal value or background) interferes in final quantification, especially when ultrafiltration is not performed. For the quantification of plasma NO − 3 we recommend: sodium EDTA as anticoagulant, no ultrafiltration of plasma, and measurement of the absorbance background of each sample.

Square-wave adsorptive-stripping voltammetry technique has been used to develop a method for the determination of fenthion in olive oil. Due to the fact that fenthion does not give any electrochemical signal at mercury electrode, the method has been based on a previous oxidation of fenthion to its metabolite, fenthion-sulfoxide, by using KMnO 4 . The metabolite gives rise to a peak due to an adsorptive-reductive process at −0.786 V. Fenthion is isolated from olive oil by carrying out a solid–liquid extraction procedure using silica cartridge, followed by a liquid–liquid partitioning with acetonitrile. The detection limit in olive oil is 78.8 ng g −1 and recoveries for four levels of fortification are ranged from 85% to 109%. On the other hand, it has been developed a method for the simultaneous determination of fenthion and its metabolite fenthion-sulfoxide, in river water. Pesticides are isolated from water by carrying out a liquid–liquid partitioning with trichloromethane. The detection limits are 0.41 ng g −1 and 0.44 ng g −1 , for fenthion and fenthion-sulfoxide, respectively. Recoveries for three levels of fortification are ranged from 96% to 103% for fenthion and 94% to 104% for fenthion-sulfoxide.

Next generation of fusion power plants needs to develop joining technologies for several components of the reactor. In this paper, a novel brazing process for joining two pieces of divertor component made of tungsten is proposed. A flexible tape, fabricated of a mixture of 86Fe-14Ti metallic powders and an organic binder, has been used as filler material. Different binder contents (from 5 up to 30 wt.%), which provides the required flexibility to the filler tape for its fitting to the divertor curved surface, have been evaluated. The proposed flexible filler tape will improve the brazing procedure, but also it could be implemented for any curved component of the power generation industry. Two fillers contents (95/5 and 90/10 powder/binder ratios) have been used for brazing tests that were carried out in a high vacuum furnace at 1350 °C for 10 min. W-W brazed joints exhibited high continuity along the joint and no wetting problems were detected. The microhardness tests gave rise to similar values and revealed that the mechanical properties of tungsten base material were not modified during the brazing cycle. The shear strength of the joints (~44 MPa) meets the mechanical requirements of the component. Keywords: Tungsten, Brazing, Fusion reactor, Joining, Plasma facing component