18 research outputs found

    Atmosphere- and Voltage-Dependent Electronic Conductivity of Oxide-Ion-Conducting Zr1-xYxO2-x/2 Ceramics.

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    Cubic, fluorite-structured solid solutions Zr1-xYxO2-x/2 (YSZ; x = 0.4-0.7) were prepared by sol-gel synthesis. Impedance measurements on pellets of 85% approximate density sintered at 1300 °C for 24 h showed strong evidence of oxide ion conduction with an inclined Warburg spike at low frequencies and capacitance values of ∼10(-6) F cm(-1) at 40 Hz. Arrhenius plots of total pellet conductivities were linear with activation energies of 1.4-1.56 eV. The conductivity decreased with x and was 2-4 orders of magnitude lower than that with optimized YSZ, x = 0.08. When the atmosphere was changed from N2 to O2 during impedance measurements, two reversible effects were seen: the Warburg spike contracted greatly, and the sample resistance decreased. These effects were more noticeable at higher x and are attributed to the introduction of p-type electronic conduction, in parallel with the preexisting oxide ion conduction. A similar reversible result was observed upon application of a direct-current (dc) bias during impedance measurements. When either pO2 is increased or a dc bias is applied, hole creation is believed to arise by the ionization of underbonded oxide ions situated near the Y(3+) dopant ions. The ionized electrons are trapped at surface oxygen species, and the holes that are left on oxygen are responsible for p-type conduction. The electrolytic domain of x = 0.4-0.7 extends up to approximately 10(-2) atm of O2 before p-type conduction is observed. The upper pO2 limit of the electrolytic domain of x = 0.08 is not known but is likely to be close to or slightly above 1 atm of O2

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    ABSTRACT. Objective. To identify empirical evidence of diagnostic delay in spondyloarthritis (SpA), determine whether sex-related differences persist, and conduct an analysis from that perspective of the possible causes, including the influence of quality research, in this group of inflammatory rheumatic diseases. Methods. A systematic review was done of delay in diagnosis of SpA in MEDLINE and EMBASE and other sources. Study quality was determined in line with the Strengthening The Reporting of OBservational studies in Epidemiology (STROBE) statement. A metaanalysis of 13 papers reporting sex-disaggregated data was performed to evaluate sex-related differences in diagnostic delay. The global effect of diagnostic delay by sex was calculated using means difference (D) through a fixed effects model. Results. The review included 23,883 patients (32.3% women) from 42 papers. No significant differences between the sexes were detected for symptoms at disease onset or during evolution. However, the mean for delay in diagnosis of SpA showed sex-related differences, being 8.8 years (7.4-10.1) for women and 6.5 (5.6-7.4) for men (p = 0.01). Only 40% of papers had high quality. A metaanalysis included 12,073 participants (31.2% women). The mean global effect was D = 0.6 years (0.31-0.89), indicating that men were diagnosed 0.6 year (7 months) before women. Conclusion. Delay in diagnosis of SpA persists, and is longer in women than in men. There are no significant sex-related differences in symptoms that could explain sex-related differences in diagnostic delay. Methodological and possible publication bias could result in sex-biased medical practice. (J Rheumatol Firs

    Valorización de la biomasa agrícola y forestal en zonas rurales de la zona mediterránea española

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    Ponència presentada al IX Simposio Iberoamericano de Ingeniería de Residuos, Panamá, del 20 al 24 de setembre de 2021Según la Directiva (UE) 2018/2001, los Estados de la Unión Europea velarán para que la cuota de energía procedente de fuentes renovables sea de al menos el 32% del consumo final bruto de energía de la UE en 2030. Entre estas fuentes de energía renovables, tiene un lugar destacado la biomasa. En España el objetivo gubernamental es que la potencia instalada de dicha biomasa debería alcanzar los 1.408 MW para el año 2030. La biomasa, además de su potencial energético, conlleva elementos de valor añadido como dinamizar el entorno rural y mitigar el riesgo de despoblación. Por tanto, en este trabajo se determina el potencial energético de la biomasa agrícola y forestal en una comarca mediterránea española. Para ello, en primer lugar, se ha calculado la cantidad de la biomasa disponible (2.261 t/año), identificando y cuantificando las superficies aptas para el aprovechamiento, y su planificación a lo largo del año. Por otro lado, a partir de análisis físico-químicos, se ha calculado el potencial energético de la mencionada biomasa y su aplicabilidad como combustible, suponiendo una producción de alrededor de 9,5 GWh/año. En segundo lugar, se proyecta construir una instalación para la transformación de esta biomasa en pellets, de manera que sirva como fuente de empleo y de riqueza para la región. Los resultados económicos muestran un periodo de retorno de aproximadamente 5 años y una rentabilidad de alrededor del 17% por lo que, ayudado por las ayudas y subvenciones, se considera una inversión rentable social y económicamente hablando.According to Directive (EU) 2018/2001, the States of the European Union will ensure that the share of energy from renewable sources is at least 32% of the gross final energy consumption of the EU in 2030. Among these renewable energy sources, biomass has a prominent place. In Spain, the government objective is that the installed biomass power should reach 1,408 MW by 2030. Furthermore, biomass carries benefit elements such as revitalizing the rural environment and mitigating the risk of depopulation. Therefore, in this work the energy potential of agricultural and forestry biomass in a Spanish Mediterranean region is determined. To do this, in the first place, the amount of available biomass (2,261 t/year) has been calculated, identifying and quantifying the suitable areas for use, and their planning throughout the year. On the other hand, based on physical-chemical analysis, the energy potential of biomass and its applicability as fuel have been calculated, assuming a production of around 9.5 GWh/year. Secondly, it is planned to build a facility for the transformation of this biomass into pellets, so that it serves as a source of employment and economic value for the region. The economic results show a payback of 5 years and internal rate of return of 17%, which is why, helped by aid and subsidies, it is considered a profitable investment socially and economically speaking

    Field-induced p-n transition in yttria-stabilized zirconia

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    Oxide ion conducting yttria-stabilised zirconia ceramics show the onset of electronic conduction under a small bias voltage. Compositions with a high yttria content undergo a transition from p-type to n-type behavior at voltages in the range 2.4 to 10 V, which also depends on oxygen partial pressure. Surface reactions have a direct influence on bulk electronic conductivities, with possible implications for voltage-induced flash phenomena and resistive switching

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    ABSTRACT. Objective. To identify empirical evidence of diagnostic delay in spondyloarthritis (SpA), determine whether sex-related differences persist, and conduct an analysis from that perspective of the possible causes, including the influence of quality research, in this group of inflammatory rheumatic diseases. Methods. A systematic review was done of delay in diagnosis of SpA in MEDLINE and EMBASE and other sources. Study quality was determined in line with the Strengthening The Reporting of OBservational studies in Epidemiology (STROBE) statement. A metaanalysis of 13 papers reporting sex-disaggregated data was performed to evaluate sex-related differences in diagnostic delay. The global effect of diagnostic delay by sex was calculated using means difference (D) through a fixed effects model. Results. The review included 23,883 patients (32.3% women) from 42 papers. No significant differences between the sexes were detected for symptoms at disease onset or during evolution. However, the mean for delay in diagnosis of SpA showed sex-related differences, being 8.8 years (7.4-10.1) for women and 6.5 (5.6-7.4) for men (p = 0.01). Only 40% of papers had high quality. A metaanalysis included 12,073 participants (31.2% women). The mean global effect was D = 0.6 years (0.31-0.89), indicating that men were diagnosed 0.6 year (7 months) before women. Conclusion. Delay in diagnosis of SpA persists, and is longer in women than in men. There are no significant sex-related differences in symptoms that could explain sex-related differences in diagnostic delay. Methodological and possible publication bias could result in sex-biased medical practice

    La formación en valores de la Policía Local

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    This paper aims to raise discussion about the current values training used in the policetraining in Spain, more specifically, in the formation to access the local police, through the approach ofsome fundamental keys in the matter and the suggestion of some issues for discussion, such as, amongothers, the need for police values training in the local police, is appropriate the current police valuestraining?, what to improve?, and, how to do it? This paper intends to provide any light on some centralaspects of the matter with the aim of promoting the rigorous and enriching discussion to contribute tothe improvement of the local police training.La presente ponencia pretende suscitar el debate acerca de la formación en valores utilizada en la formación policial en España, más concretamente, en la formación de ingreso en la Policía Local, a través del abordaje de algunas claves fundamentales en la materia y el lanzamiento de algunas cuestiones para el debate como, entre otras, la necesidad de la formación en valores en la policía local, ¿es adecuada la formación en valores que se está realizando?, en su caso, ¿en qué hay que mejorar?, y ¿cómo hacerlo? Este trabajo pretende aportar alguna luz sobre algunos aspectos centrales de la materia con el objetivo de fomentar el debate riguroso y enriquecedor que contribuya a la mejora de la formación de la policía local

    Table_1_Disease activity indexes might not capture the same disease aspects in males and females with ankylosing spondylitis: A real-world nationwide analysis.DOCX

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    BackgroundTo evaluate gender differences in disease activity and health status (HS) in patients with radiographic axial spondyloarthritis (r-axSpA)/ankylosing spondylitis (AS).MethodsAncillary analysis of the MIDAS study, an observational, non-interventional, cross-sectional and retrospective multicenter nationwide study to assess disease activity and its relationship with HS in clinical practice. Adult patients with AS diagnosis, fulfilling ASAS and modified New York criteria, treated for ≥3 months upon study inclusion according to clinical practice were included. The primary outcome was “disease control” assessed by the percentage of patients in remission and low disease activity (BASDAI and ASDAS-CRP scores). HS was evaluated using the ASAS health index (ASAS-HI). Patients' responses and characteristics were analyzed by gender.ResultsWe analyzed 313 patients with AS, 237 (75.7%) males and 76 (24.3%) females. A total of 202 (64.5%) patients had adequate disease control (BASDAI ConclusionThis study showed a higher proportion of females with AS and active disease using the BASDAI definition. When using the ASDAS-CRP definition these differences by gender were less pronounced. The impact of disease activity on HS appears to be higher in females than males.</p
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