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The use of magnesium and its alloys has increased in recent years due to their low weight, high strength, excellent machinability, and high dimensional durability. Therefore, they have found applications in communications, automotive and aerospace industries, among others. However, their high negative reduction potentials, low chemical stability, and unstable native oxide films have limited their use, particularly in applications that require high corrosion resistance.1-3 The application of sol-gel coatings has shown to be an effective method to overcome this problem. In this context, this study aimed to develop sol-gel thin films doped with ecological corrosion inhibitors for corrosion protection of AZ61 alloy surfaces. The objective was to determine whether these new systems could provide an alternative to the replacement of chromates, surface pre-treatments and chemical conversion coatings that contain conventional corrosion inhibitors, which are currently being questioned for their harmfulness to health and the environment.4 Methyltriethoxysilane (MTEOS) and tetraethylorthosilicate (TEOS) were used as precursors to produce sols, which were then modified with active corrosion protection dopants. Eco-benign corrosion inhibitors, such as L-cysteine (L-Cys), lanthanum (III) acetate hydrate, and lanthanum (III) isopropoxide were incorporated in the sol-gel matrix as dopants. A set of sol-gel coatings was modified with a common dopant, benzotriazole (BTA), for comparison purposes, as it is a well-known effective corrosion inhibitor. However, this chemical compound is known to be carcinogenic and toxic to flora and fauna, and its use is currently being restricted today in compliance with environmental protection regulations.5,6 The resulting sols were processed and deposited on AZ61 substrates by dip-coating technique, producing transparent sol-gel thin-films. The thickness of the films was evaluated by interference of reflection spectra. Their chemical composition was

El GAAF_CoEduLAB es un Proyecto de Innovación Docente de la Facultad de Formación del Profesorado y Educación de la Universidad Autónoma de Madrid que se inició con un Proyecto INNOVA (2020-2021), consolidándose en un Proyecto Implanta (2021-2022). Emerge ante la necesidad de revisar la formación del profesorado con enfoque feminista, tras la detección de actitudes y sesgos sexistas, así como la invisibilidad de la experiencia femenina y el enfoque de género en los planes de estudio. Esta propuesta persigue los siguientes objetivos que se alcanzan mediante diferentes metodologías activas: (1) Crear una Comunidad de Aprendizaje feminista formada por docentes y alumnado; (2) Impulsar la coeducación y pedagogía feminista en la formación inicial y continua; (3) Realizar iniciativas de activismo feminista. Como resultado, se observa un incremento en el número de integrantes del Grupo Promotor, un aumento del alumnado participante en las distintas iniciativas en diferentes asignaturas. También ha incrementado la relevancia y repercusión en la Facultad tanto en el espacio físico como en el espacio virtual. Ante los positivos resultados y la necesidad de profundizar la educación de calidad con enfoque de género, éste pretende ser un ejemplo de buenas prácticas coeducativas trasladable a toda la comunidad universitaria y otros niveles educativos.

Materials such as wood, textiles, or plastics that are part of the exhibition system in museums are known to emit pollutants such as organic acids. Scientific and technical objects that include these materials in their composition can themselves be a potential source of emissions, which, together with inappropriate humidity and temperature conditions, can lead to corrosion of the metallic parts. In this work, we have studied the corrosivity of different locations in two venues of the Spanish National Museum of Science and Technology (MUNCYT). Coupons of the most representative metals from the collection were placed in different showcases and rooms for 9 months. The corrosion of the coupons has been evaluated in terms of the rate of mass gain, colour changes and characterisation of the corrosion products. The results were correlated to the relative humidity and concentration of gaseous pollutants to determine which metals are most susceptible to corrosion. The results show that metal artefacts exposed in showcases have a higher risk of corrosion than those exposed directly in the room, and that some pollutants are emitted by the artefacts. The corrosivity of the museum environment is low for copper, brass, and aluminium in most locations; however, some placements present a higher aggressivity for steel and lead, due to the high humidity and the presence of organic acids.

The use of magnesium and its alloys has increased in recent years due to their low weight, high strength, excellent machinability, and high dimensional durability. Therefore, they have found application in communications, automotive and aerospace industries, among others. However, their high negative reduction potentials, low chemical stability, and the unstable native oxide films have limited their use, particularly in applications that require high corrosion resistance.1-3 The application of sol-gel coatings has shown to be an effective method to overcome this problem. In this context, the aim of this study was to develop sol-gel thin-films doped with ecological corrosion inhibitors for corrosion protection of AZ61 alloy surfaces. The objective was to determine whether these new systems could provide an alternative to the replacement of chromates, surface pre-treatments and chemical conversion coatings that contain conventional corrosion inhibitors, which are currently being questioned for their harmfulness to health and the environment.

Since interleukin-6 (IL-6) is a pivotal proinflammatory cytokine implicated in the pathogenesis of giant cell arteritis (GCA), we aimed to determine the potential association of the functional IL6 -174 G/C polymorphism with GCA as well as if the single base change variation at the promoter region in the human IL-6 gene may account for differences in the clinical spectrum of GCA between cranial and extracranial large vessel vasculitis (LVV)-GCA.

Improvements regarding durable lubrication together with minimized wear are mandatory for obtaining long-term, functioning metallic joint prostheses. For this goal, CoCr surface was functionalized with Graphene Oxide (GO), characterized by FTIR and XPS, and tested at tribocorrosion. Deposition of graphene oxide was carried out by consecutive steps: alkalinization of CoCr; intermediate coupling via 3-aminopropyltriethoxysilane (APTES) which was cured at 45 °C for 24 h; and final assemble of GO layers at 60 °C for 24 h upon exposure with silane-coated CoCr. FTIR displayed C=C band confirming the assembly of GO on silane-coated CoCr surfaces. XPS elucidated reaction between primary amines of APTES and epoxy groups of GO, free -OH groups in APTES and carboxyl groups in GO, and reaction between APTES primary amines and -OH from carboxyl groups of GO. COF values for GO incubated on silane-coated CoCr disks show stationary values near 0.2. CoCr surfaces in as-reception state show higher COF values increasing at longer testing times.

The dramatic texture and microstructural changes observed in 6061Al-20vol%SiC metal matrix composite undergoing severe thermal cycles, under the absence and the simultaneous action of an external tensile stress, are studied. Under only thermal cycles (100–450 °C) homogenization and disorientation of the SiC whisker reinforcement and crystallographic texture randomization occurs. However, when a simultaneous tensile stress is applied, the whiskers rotate so that their long direction aligns with the tensile axes. Furthermore, a strong texture and large deformations (superplasticity), higher than 1000%, are achieved. These results are explained on the basis of the microscopic stress fields generated at the different microstructural scales (stresses of type II and type III) and well-known observation of dislocation generation at the SiC-metal interface during the cooling period of the cycles. We propose that moving dislocations (responsible of type III stresses) operate differently under the absence or the presence of the external stress. Under no stress, dislocation motion (occurring mainly during the heating period) is driven only by the type II internal stress. However, dislocation motion is improved when an external stress is applied, leading to texture changes and large elongations. Despite that a low external stress is applied, it overcomes the effect of the internal stresses for dislocation motion.

Different studies carried out in the last three decades on the magnetic susceptibility of the spinel ZnFeO ferrite have revealed the positive character of its Curie–Weiss temperature, contradicting its observed antiferromagnetic behavior which is characterized by a well-defined susceptibility peak centered around the Neel temperature (10 K). Some approaches based on ab initio calculations and mixture of interactions have been attempted to explain this anomaly. This work shows how for very low values of the inversion parameter, the small percentage of Fe atoms located in tetrahedral sites gives rise to the appearance of ferrimagnetic clusters around them. Superparamagnetism of these clusters is the main cause of the anomalous Curie–Weiss behavior. This finding is supported experimentally from the thermal dependence of the inverse susceptibility and its evolution with the degree of inversion.

Improvements in durable lubrication together with minimized wear are essential for obtaining long-term, functioning metallic joint prostheses. To achieve this objective, CoCr surface was functionalized with Graphene Oxide (GO) and characterized by FTIR and XPS. CoCr alloy was subjected to alkalinization in order to generate high hydroxyl content on the surface. FTIR and XPS revealed reactive OH groups, enabling intermediate coupling via (3-aminopropyl) triethoxysilane (APTES), which was cured at 45 °C and 75 °C for 24 h and 30 min, respectively. FTIR revealed cross-linked films (Si–O–Si), inferring condensation and self-assembly of silane layers, while XPS revealed the presence of NH, enabling chemical binding of GO. Silane-coated CoCr disks were immersed in GO solution at 60 °C for 12h and 24h, respectively. FTIR displayed C[dbnd]C band confirming the assembly of GO on silane-coated CoCr surfaces. XPS revealed three possible surface mechanisms: (1) reaction between primary amines of APTES and epoxy groups of GO; (2) free –OH groups in APTES and carboxyl groups in GO; and (3) reaction between APTES primary amines and –OH from carboxyl groups of GO. Overall, the multilayer system CoCr–OH–Si45-GO24h showed covalent functionalization of metal substrate with GO to a large extension of surface area among all the multilayer systems studied.

The effect of laser surface melting on the corrosion resistance of AZ31 Mg alloy in 0.1 M NaCl solution was investigated using different laser processing conditions (energy densities of 14 and 17 J cm). Laser treatment induced rough surfaces primarily composed of oxidized species of Mg. XPS analysis revealed that the surface concentration of Al increased significantly as a consequence of LSM. Electrochemical impedance spectroscopy showed that the laser treatment remarkably increased the polarization resistance of the AZ31 Mg alloy and induced a passive-like region of about 100 mV, as determined by potentiodynamic polarization. Analysis of the results obtained provide solid evidence that within the immersion times used in this study, LSM treatment increased the corrosion resistance of AZ31 Mg alloy under open circuit conditions and anodic polarization.

Weathering steels are widely used in civil engineering, architecture and contemporary art due to their mechanical properties, their enhanced resistance to atmospheric corrosion as well as their aesthetic properties. Artists and blacksmiths often apply chemical treatments to obtain the appealing colors of a patina in a shorter period of time. However, the development of an accelerated patina may have an effect on the final appearance and color of the surface. With the aim of evaluating differences in color and studying the evolution of the surface, eight accelerated patinas were made and exposed to the atmosphere for periods of time of up to 24 months and were compared to a natural patina. The characterization studies showed the presence of lepidocrocite on the surface. A close inspection of the X-ray diffraction patterns showed the displacement of the (020) lepidocrocite reflection and asymmetric broadening of selective lines of this phase that were associated to stacking and twins faults, respectively. These faults decrease with the exposure time and are related to a maximum at 630 nm in the reflectance spectrum and the stabilization of the b* coordinate (yellow color). The colors of the accelerated patinas differ from the natural patina at short exposure times. However, they tend to converge at longer exposure times.