Efecto del tipo y cantidad de alúmina como dopante sobre la densificación y las propiedades eléctricas de electrodos cerámicos de óxido de zinc

[EN] Aluminum-doped zinc oxide (AZO) electrodes can be a good alternative to replace the expensive electrodes (Ti, ITO, FTO, etc.), which are used in the electrooxidation process to remove refractory and emergent contaminants from industrial wastewaters. AZO electrodes have been prepared by the traditional ceramic method using ZnO as the main raw material and different precursors of Al2O3 as dopant sources. Densification, microstructure and electric resistivity of AZO electrodes are a function of precursor's nature and sintering thermal treatment. The higher the number of precursor's particles and the smaller their size, the sintering temperature needed to attain high densifications and low resistivities shifted to higher values. Micrometric and colloidal alumina were the precursors which allowed to equilibrate an affordable sintering temperature interval (1200-1300 degrees C) with acceptable densification and resistivity values (around 95% and 5 x 10(-3) Omega cm, respectively). However, colloidal alumina made it possible to obtain slightly lower values of resistivity at the cost of having a narrower working interval.[ES] En este trabajo de investigación se presentan electrodos cerámicos de óxido de zinc dopado con aluminio (AZO) como alternativa a los actuales electrodos de titanio (ITO, FTO. . .) utilizados en el proceso de electrooxidación de aguas residuales para la eliminación de contaminantes refractarios y emergentes. Estos electrodos AZO han sido preparados mediante el método tradicional cerámico, utilizando ZnO como materia prima principal y diferentes precursores de Al2O3 como dopantes. La densificación, la microestructura y la resistividad eléctrica de estos electrodos son propiedades que están directamente relacionadas con la naturaleza del precursor y con eltratamiento térmico utilizado para su sinterización. Cuanto mayor es el número de partículas del precursor y menor es su tamano, ¿ la temperatura de sinterización necesaria para lograr altas densificaciones y bajas resistividades cambia a valores más altos. Fueron la alúmina micrométrica y la coloidal los dopantes que ofrecieron un buen equilibrio entre temperatura de sinterización (1.200¿1.300 ¿C) y densificación-resistividad (95% y 5·10¿3 cm, respectivamente). Concretamente en el caso de la alúmina coloidal, se pudieron optimizar estos resultados estrechando el intervalo de temperatura de trabajo.The authors thanks to"Ministerio de Economia y Competitividad" and "Fondo Europeo de Desarrollo Regional" the support to this research [Plan Nacional de I+D, project Ref. CTQ2015-65202-C2-2-R (MINECO/FEDER)].Sánchez-Rivera, M.; Orts, M.; Pérez-Herranz, V.; Mestre, S. (2021). Effect of type and amount of alumina as dopant over the densification and the electrical properties of zinc oxide ceramic electrodes. Boletín de la Sociedad Española de Cerámica y Vidrio. 60(1):53-61. https://doi.org/10.1016/j.bsecv.2020.01.003536160

Trabajo temporal y siniestralidad laboral en España en el período 1988 - 1995.

Sin resume

Role of starch characteristics in the properties of low-cost ceramic membranes

Starch is used as porosity generator in membranes and other porous ceramics. A study was conducted to evaluate the effects of the characteristicsof starches (impurities, particle size), obtained from potato, pea, maize and wheat, on the properties of microfiltration membranes formulated withtraditional raw materials (the ceramic matrix was composed of quartz, albite and mullite). The results indicated that the pore size distributionand the permeability coefficient of the membrane can be controlled by modifying only the particle size of starch. In this way, correlations wereobtained between surface mean diameter of starch and membrane properties (characteristic pore diameters d16and d50, and permeability coefficient).Moreover, it is necessary to use a starch having a mean particle size greater than about 50 m in order to obtain a significant change in the poresize distribution and an increase in the permeability of the membraneThe authors thank Spanish Ministerio de Economia y Competitividad for their support for the development of this research (Plan Nacional de I+D, ref. CTQ2012-37450-C02-02).Lorente-Ayza, MM.; Orts, M.; Pérez-Herranz, V.; Mestre, S. (2015). Role of starch characteristics in the properties of low-cost ceramic membranes. Journal of the European Ceramic Society. 35(8):2333-2341. https://doi.org/10.1016/j.jeurceramsoc.2015.02.026S2333234135

X chromosome inactivation does not necessarily determine the severity of the phenotype in Rett syndrome patients

Rett syndrome (RTT) is a severe neurological disorder usually caused by mutations in the MECP2 gene. Since the MECP2 gene is located on the X chromosome, X chromosome inactivation (XCI) could play a role in the wide range of phenotypic variation of RTT patients; however, classical methylation-based protocols to evaluate XCI could not determine whether the preferentially inactivated X chromosome carried the mutant or the wild-type allele. Therefore, we developed an allele-specific methylation-based assay to evaluate methylation at the loci of several recurrent MECP2 mutations. We analyzed the XCI patterns in the blood of 174 RTT patients, but we did not find a clear correlation between XCI and the clinical presentation. We also compared XCI in blood and brain cortex samples of two patients and found differences between XCI patterns in these tissues. However, RTT mainly being a neurological disease complicates the establishment of a correlation between the XCI in blood and the clinical presentation of the patients. Furthermore, we analyzed MECP2 transcript levels and found differences from the expected levels according to XCI. Many factors other than XCI could affect the RTT phenotype, which in combination could influence the clinical presentation of RTT patients to a greater extent than slight variations in the XCI pattern

Engineering zirconia coating microstructures by using saccharides in aqueous suspension plasma spraying feedstocks

This study aims to demonstrate the feasibility to develop columnar microstructures in zirconia coatings manufactured by suspension plasma spray, through the modification of the properties of the suspension feedstocks with different common monosaccharides: fructose, ribose and glucosamine. The research also pretends to relate the properties of the suspensions to the final coatings. For the study, the saccharides suspensions were characterised in terms of physical and rheological properties. Then, highly concentrated suspensions containing the saccharides were plasma sprayed under the same spraying conditions. The experimental study with optic and scanning electron microscopy was used to evaluate the microstructure of the coatings and their characteristics, while the confocal laser scanning microscope (CLSM) was used to carry out a precise study of the surface topography. Results showed that saccharides produce a strong influence on the proliferation of columnar structures in the coating cross-section visible as cluster (cauliflower-like) structures on the surface. This effect is due to the diminution of water surface tension as well as an extra energy input during combustion of the saccharides. CLSM has allowed a detailed examination of the topography of the coatings to clearly quantify the differences observed in relation to the development of columnar microstructure.All the authors would like to thank the support received by theSpanish Ministry of Science, Innovation and Universities and FEDER Funds, through the research project (ref. RTI2018-099033-B-C31 andC33). V. Carnicer would like to acknowledge to the Research Promotion Plan of the University Jaume I for the predoctoral fellowship (ref.PREDOC/2017/51). Moreover, all authors would also like to thank Dr.Paulina Wiecinska for her helpful discussions and approach to thesaccharides

Effect of feedstock and plasma gun on the microstructure and bioactivity of plasma sprayed bioactive glass coatings

International audienc

Actitud de la enfermería hacia la práctica clínica

Ponencia presentada en la I Jornada de cuidados de la salud basados en la evidencia en la Comunidad Valenciana "Hacia la excelencia en cuidados", Instituto de investigación sanitaria la Fe (Valencia), 7 de junio de 2018Actualmente la práctica clínica diaria, obligada por la presión asistencial existente, que el personal sanitario y por consiguiente los equipos de enfermería deben decidir en espacios cortos de tiempo, y sobre los focos de múltiples presiones sometidas por los procesos de asistencia sanitaria, sucediendo esto en ocasiones de la forma menos adecuada debido a lagunas en la información tal como se desearía. Estas sucesos tal como hemos descrito en apartados anteriores provocan ante las acciones del personal sanitario una enorme variabilidad (Cabrero García, Orts-Cortés, López-Coig, Luisa Velasco, & Richard-Martínez, 2005; Fernández Martín, 2009). Encontramos pues a lo largo de nuestra práctica clínica, un proceso sistémico en los cuidados procurados por los Profesionales de Enfermería, el cual refleja una alta variabilidad en desarrollo de los procesos de los cuidados aplicados por los profesionales de enfermería, variabilidad que no está correspondida a las evidencias científicas que se han logrado alcanzar con el fin de reducir los efectos adversos del proceso de cuidado

Cool products for building envelope - Part I: Development and lab scale testing

The paper describes the methodology followed for the development of new cool products in order to widen the range of existing solutions both including coloured (even dark) materials and extending the application also to building vertical components. Cool coloured ceramic tiles and acrylic paints for facades and roof membranes have been developed and tested at lab scale. Spectral reflectance measurements have been performed demonstrating a significant improvement of reflectance in the Near InfraRed (NIR) range (up to +0.40) while keeping dark colour and high absorbance in the visible. The development of new products has been also oriented to the improvement of durability properties, being this aspect of relevance for high reflecting materials that have to keep their cooling properties over the time. While ceramic tiles naturally offer superior resistance to outdoor ageing, a significant increase of biological growth resistance has been achieved also for roof membranes by including ZnO nanoparticles. The approach followed by the authors aimed at delivering products, that besides having higher NIR reflectance, were capable of satisfying industrial and market requirements being compatible with standard manufacturing processes and offering additional functionalities. A complementary paper will be dedicated to the extensive experimental and numerical evaluation of new materials’ thermal performances