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Platinum (Pt) nanoparticles were synthesized by pulsed laser ablation in liquid (PLAL) technique in different liquids (acetone, ethanol, and methanol). Ablation was performed using a Q-switched Nd:YAG laser with output energy of 230 mJ/pulse for 532 nm wavelength. Ablation time and laser energy fluence were varied for all the liquids. Effects of laser energy fluence, ablation time, and nature of the liquid were reported. The mean size, size distributions, shape, elemental composition, and optical properties of Pt nanoparticles synthesized by PLAL were examined by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV-Visible absorption spectroscopy.

Hercynite nanoparticles were obtained by pulsed laser ablation of hercynite in liquid media technique. Colloidal solutions of hercynite nanoparticles were synthesized in three different liquids by ablation using 532‐nm output of a pulsed Nd:YAG laser with three laser fluencies. Transmission electron microscopy, selected area electron diffraction, energy‐dispersive X‐ray analysis, and X‐ray photoelectron spectroscopy were used for the characterization of these nanoparticles. The nanoparticles obtained were of spherical shapes with cubic crystalline structure. It was observed that the laser fluence and liquid media could affect the morphology and size of hercynite nanoparticles.

The chemical environment and the internal conditions of the furnaces and ladles are extremely aggressive for the refractories, so metallurgical industries demand refractory linings with greater durability and resistance to avoid unforeseen stoppages and to reduce the changes of the furnace lining. Therefore, the current work aims to evaluate the impact of the additions of ZrO 2 -nanoparticles (1, 3, and 5 wt. %) in magnesia-based bricks. A comparative study of the physical and chemical properties in bricks obtained using two cold pressing techniques (uniaxial and isostatic pressing) and two sintering temperatures (1550 and 1650 • C) was carried out. The microstructure and crystalline phase characteristics obtained after the heat treatments and the slag corrosion test was studied using scanning electron microscopy/electron dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD). The results reveal that the sample with 5 wt. % of ZrO 2 nanoparticles (obtained by cold isostatic pressing and sintering at 1650 • C) has the lowest porosity and greatest resistance to penetration of blast furnace slag.2 of 20 to the martensitic transformation of the steels [2]. Zirconia confers to the refractories the following properties: strength, toughness, and chemical resistance under severe conditions. On the other hand, magnesium oxide (MgO) is a basic refractory material characterized by its refractoriness (high melting point, around 2800 • C). This material also has a thermal conductivity of 48 W/m·K at room temperature and has a good resistance to corrosion in the presence of basic material. Magnesia refractories, which are manufactured by mixing magnesium oxide with other materials (carbon, spinel, chromite, etc.) to obtain bricks with different shapes, are used in the lining of both furnaces and ladles employed in the metallurgical industry (basic oxygen furnace (BOF), electric arc furnaces (EAF), argon-oxygen-decarburization (AOD), ladle metallurgical furnaces (LMF), cement kilns and furnaces for nonferrous materials [3]).The main consumer of magnesia-based refractory bricks is the metallurgical industry, and particularly the iron and steelmaking industry, where they are mainly used in the slag line of the LMF, in the EAF and in the BOF [4]. Other consumers of magnesia bricks (magnesia-chromite) are the submerged arc furnaces (SAF) used in the copper manufacturing process, because of the resistances to the chemical degradation by molten phases and to the abrasion, the thermal shock resistance and the mechanical strength [5].Presently, the industry requires research on refractories with better properties that are manufactured using new technologies of agglomeration (faster, cheaper and cleaner) to improve their processes, for instance, studies of: new clean techniques of sintering (solar synthesis, laser, microwave and conventional sintering), synthesis of ceramic composites, incorporation of additives to improve properties of the refractories and study of nanomaterials added to the refractory matrix [6][7][8][9][...

In this work, we studied the phases in a Mg-Ti-O system using a 1:1 formulation of MgO:TiO2, mixing synthetic brucite of Mexican origin with TiO2 microparticles of high purity, with a heat treatment at 1100 °C for 1 h. Due to its valence electrons, TiO2 can contribute to the sintering process to improve density in MgO products. The raw materials and formulation by XPS and X-RD techniques were characterized. The results demonstrate the presence of different oxidation states in titania and the formation of different oxides in the Mg-Ti-O system when mixed and calcined at 1100 °C; additionally, we estimated the formation of vacancies in the crystal lattice during the transformation from hexagonal brucite to magnesia with a cubic structure centered on the faces. Its thermal behavior is indicated by the MgO-TiO2 phase diagram.