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The paper had as purpose the fabrication and characterization of magnetic nanoparticles covered with TiO2 for applications in environmental field. The research consisted in investigating the properties of magnetic iron nanooxides, synthesized from ferric and ferrous chloride and then covered with TiO2, with minimum costs and high efficiency in industrial wastewater treatment. The iron nanoparticles were obtained by co-precipitation method and the titan dioxide was obtained by sol-gel method. After covering the nanoparticles with TiO2, the samples were characterized by X-Ray diffraction (XRD) and scanning electron microscopy (SEM).

The paper presents results of researches carried out to establish the causes that led to the cracking of forgings made of manganese low alloy steel microalloyed with boron. The researches includes analysis of samples taken from the forgings in the cracked surface area and also analysis of a sample from forged material. The following methods and techniques were used for investigation:metallographic analysis by optical microscopy;visual macroscopic examination by scanning electron microscopy (SEM) at low magnification, using scanning electron microscope;examination by scanning electron microscopy on the material cracks area and its adjacent area;investigation of material by X-ray microanalysis in energy dispersive (EDAX) for its characterization, in terms of microcomposition

The paper presents the investigations made on samples taken from the related rotor blade of an hospital cooling equipment.The failure analysis was made in order to find if the failure appear because the metallic material used or was functional problem.The objectives of our analysis and techniques used are described below:determining the chemical composition by optical emission spectrometry;determining the hardness of the material;metallographic analysis by optical microscopy;micro compositional and microstructural analysis by scanning electron microscopy (SEM) and by microanalysis, energy dispersive X-ray (EDAX). Research has highlighted the quality of piece elaboration and casting, which led to a long life of its use.

The paper emphasizes the importance of use the nano-iron oxides as treatment materials for wastewaters decontamination, having in mind the size of these compounds and specific surface area suitable for retaining toxic metals such as chromium or cadmium presented as major pollutants for industrial wastewaters. Also, the magnetic properties of the nano-iron oxides offer the possibility of a fast removal of these from the system, after wastewaters treatment. The obtaining of some core-shell composites with nano-iron oxides as core represent an advantage because of the dissolving tendency of the nano-iron oxides under acidic conditions, the situation being common to the industrial wastewaters.