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A dense Ce0.9Gd0.1O2−d (GDC) interlayer is an essential component of the SOFCs to inhibit interfacial elemental diffusion between zirconia‐based electrolytes (eg YSZ) and cathodes. However, the characteristic high sintering temperature of GDC (>1400°C) makes it challenging to fabricate an effective highly dense interlayer owing to the formation of more resistive (Zr,Ce)O2 interfacial solid solutions with YSZ at those temperatures. To fabricate a useful GDC interlayer, we studied the influence of transition metal (TM) (Co, Cu, Fe, Mn, & Zn) doping on the sintering and electrochemical properties of GDC. Dilatometry data showed dramatic drops in the necking and final sintering temperatures for the TM‐doped GDCs, improving the densification of the GDC in the order of Fe > Co > Mn > Cu > Zn. However, the electrochemical impedance data showed that among various transition metal dopants, Mn doping resulted in the best electrochemical properties. Anode supported SOFCs with Mn‐doped, nano, and commercial‐micron GDC interlayers were compared with regard to their performance and stability levels. Although all of the SOFCs showed stable performance, the SOFC with the Mn‐doped GDC interlayer showed the highest power density of 1.14 W cm−2 at 750°C. Hence, Mn‐doped GDC is suggested for application as an effective diffusion barrier layer in SOFCs. [ABSTRACT FROM AUTHOR]

A sluggish oxygen reduction reaction (ORR) is an inveterate challenge limiting the performance of solid-oxide fuel cells (SOFCs). Surface modification through the infiltration of nanoparticles is recognized as a facile technique to enhance the performance of state-of-the-art cathode materials. However, achieving stoichiometric uniformity and thermal stability of infiltrated nanoparticles needs further exploration. In this study, we demonstrate a novel ultrasonic spray infiltration technique to realize the surface modification of a La0.6Sr0.4Co0.2Fe0.8O3−δ/Gd0.1Ce0.9O2−δ composite cathode through the infiltration of a Sm0.5Sr0.5CoO3−δ cathode catalyst. Infiltration by this new technique dramatically reduces the area-specific ohmic and polarization resistances, resulting in twofold enhanced performance of the anode-supported SOFC. In contrast, only a slight increase in the performance is achieved by infiltration through a micropipette. The performance improvement through ultrasonic spray infiltration is attributed to the uniform dispersion of the catalyst in the form of a nanolayer. Moreover, TEM analysis has revealed an epitaxial deposition of Sm0.5Sr0.5CoO3−δ forming a layered perovskite structure at the La0.6Sr0.4Co0.2Fe0.8O3−δ/Sm0.5Sr0.5CoO3−δ interface leading to sustained high-performance outcomes. On the contrary, infiltration by micropipette did not produce such uniform morphology of infiltrated nanoparticles and also indicated elemental segregation giving rise to impure phase formation. The ultrasonic spray infiltration technique proposed here represents a viable and commercializable solution to produce SOFCs with high and stable performances. [ABSTRACT FROM AUTHOR]

Objective: Kenya's 1985 education reform implemented curriculum changes to prepare children for the job market and changed the instructional language from English to local ethnic languages during the first three years of primary education. This article examines the reform's impact on (i) level of education completed, (ii) income level, and (iii) preference for national versus ethnic interests. Methods: Using survey data collected from randomly selected Kenyan citizens in Nairobi, this article uses a regression discontinuity (RD) design comparing the first cohort exposed to the reform to those who were not. Results: The education and income levels of those beginning their education under the reform were higher. The reform did not influence preference for national or ethnic interests. Conclusions: The reform partially increased children's job market preparation but was unsuccessful in addressing unemployment. Teaching children in local languages exhibited no negative effects on ethnic as opposed to national interests. [ABSTRACT FROM AUTHOR]

The sacrococcygeal area supports the lower body and endures mechanical forces during movement. However, current treatment methods for deep caudal sacrococcygeal defects have limitations, resulting in insufficient tissue for deep pocket obliteration and considering only the two-dimensional advancement plane in a three-dimensional defect topology. Our study proposes using a rotational V-Y fasciocutaneous advancement island flap to reconstruct deep caudal sacrococcygeal defects. By considering the three-dimensional nature of the defect, we distinguish a coccygeal plane of the V-Y flap from a sacral plane and set different directions and depths of movement for each plane. From March 2016 to July 2022, 12 patients underwent successful treatment with this surgery, and no complications or recurrences were observed in the study group. Our research found that patients in our study exhibited a smaller intercoccygeal angle than the average angle of the general Korean population, as previously reported. This implies a more pronounced curvature between the sacral and coccygeal planes. Therefore, our methods, which consider the three-dimensional structures of sacrococcygeal pathology, are significant. This technique provides a mechanically robust reconstruction after resecting deep sacrococcygeal pathology, with well-padded tissue to prevent dead space and wound disruption. [ABSTRACT FROM AUTHOR]