The synthetic tetrapyrrole macrocycles, such as porphyrins (H2P) and phthalocyanines (H2Pc), exhibit interesting physicochemical properties suitable to be used in modern technology. For many applications, those species should be trapped or fixed inside graphite, hydrotalcites, silica, TiO2, or polymers. Methodologies for the optimization of the properties of porphyrins, trapped or fixed inside polymers, have been barely developed. Our research works in the development of methodologies for the optimization of incorporation and display of properties of tetrapyrrole macrocycles inside inorganic, polymeric, or hybrid networks. This paper shows some results about the effect of the spatial disposition of the amine (–NH2) groups attached on the periphery of substituted tetraphenylporphyrins, on the Nylon 66 structure and on the display of the physicochemical properties of the trapped macrocycles. Nylon 66 was synthesized from adipoyl chloride and hexamethylenediamine in presence of tetraphenylporphyrins substituted with –NH2groups localized at theortho- orpara-positions of the phenyls. Cobalt complexes formation was used to quantify the amount of porphyrins in the polymer fibers. Characterization results show that the spatial position of amine groups of the porphyrins has important structural and textural effect on the Nylon 66 fibers and on the fluorescence of the porphyrins integrated into the fibers.

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A study on the use of Salvia hispanica (Chia) as green corrosion inhibitor for 1018 carbon steel in 0.5 M H 2 SO 4 has been carried out by using electrochemical impedance (EIS) and electrochemical noise measurements (EN). Parameters such as polarization and noise resistance were obtained and Hurst exponent and fractal dimension were calculated. Both techniques showed that Salvia hispanica acts as good inhibitor since the corrosion rate decreased by more than one order of magnitude with its addition. Hurst exponent and fractal dimension calculations gave very similar results. Inhibitor efficiency was 90% for up to 24 hours of immersion.

This paper proposes a new approach to Proton Exchange Membrane (PEM) electrolysis, by replacing the conventional anodic reaction, by a lower energy reaction requirement with technological application. Hydrogen is generated in the catholyte, through the reduction of protons over a stainless steel cathode immersed in acidic medium (H 2 SO 4 1M), with a potential gradient of 1V using a solar panel as power source. In a Na 2 SO 4 0.05M (pH≈2.5) anolyte solution, a mixture of Fe 2+ /Fe 3+ ions from the oxidation of a sacrificial electrode made of carbon steel mesh is produced. The generation of iron ions in the anolyte is harnessed for the development of a Fenton type process in the presence of H 2 O 2 . Fe 2+ /Fe 3+ ions interact with H 2 O 2 , generating strong oxidants which are responsible for the organic matter oxidation. The results showed that is possible to oxidize, different concentrations (0.00012M and 0.00024M) of Reactive Black 5 (RB5) textile dye waste in 40 minutes.

To evaluate the electrochemical parameters of the reinforced concrete specimens at laboratory level there is no problem at all, because one can use any well-known electrochemical technique, but in site monitoring, there are few techniques being able to obtain these parameters. In this work a viable alternative is presented for the electrochemical evaluation of the reinforced concrete specimens in laboratory or in site monitoring. In order to have a reference of the corrosion rate obtained with the electrochemical noise technique and to be able to establish if these are real ones, measurements with commercial equipment were made applying the polarization resistance technique.Keywords: corrosion, electrochemical noise, polarization resistance, armed concrete, monitoring. IntroducciónEn la industria de la construcción, el hormigón armado con barras de acero es el material más empleado en todo el mundo, debido a su facilidad para moldearse y formar cualquier estructura geométrica, la corrosión del acero de refuerzo tiene una elevada frecuencia con que ocurre, por lo que puede decirse que la corrosión del acero del armado es una de las principales causas de que las estructuras de hormigón armado sufran deterioro prematuro.