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A series of Sr1−xDyxTi1−yNbyO3−δ (0.05 ≤ x, y ≤ 0.10) samples were fabricated using cold compaction, followed by sintering in a (95% N2 + 5% H2) reducing atmosphere. We studied the crystal structure and optical properties of Sr1−xDyxTi1−yNbyO3−δ using X-ray diffraction (XRD) with Rietveld refinement, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet−visible−near-infrared (UV−VIS−NIR) spectroscopy. The sintered Sr1−xDyxTi1−yNbyO3−δ had a tetragonal structure (I4/mcm space group). In the sintered samples, Ti ions existed as a mixture of Ti3+ and Ti4+, and Nb ions existed as a mixture of Nb4+ and Nb5+. The band-gap energies decreased with increasing Dy/Nb concentrations. The incorporation of Ti and Nb ions, the formation of both Ti3+ and Nb4+ ions, and the reduction in band-gap energies are likely highly effective for increasing the electron concentration and the corresponding electrical conductivity. Sr1−xDyxTi1−yNbyO3−δ with high electrical conductivity is suitable for energy and electronics applications. [ABSTRACT FROM AUTHOR]

Using an analogy in science and everyday life is a double-edged sword because they are accompanied by alternative ideas, in addition to scientific concepts. Schools and public education explain global warming by making a common analogy between this phenomenon and greenhouse effects (Chen in Philos Cogn Sci 105-114, 2012 (See CR9)). Unfortunately, this analogy sometimes produces various incorrect explanatory mental models. To construct a correct understanding of global warming, it is necessary: first, to investigate the attributes of analogical reasoning; second, to understand these features by restructuring the greenhouse analogy; and third, to explore the problems and benefits of the greenhouse analogy. The characteristics of relations, rather than objects, must be mapped according to the principle of systematicity, but the public tends to preserve the attributes of the base domain, which is mapped relatively easily. In conclusion, certain facets of the prevailing greenhouse analogy cause a distorted public view of climate change. We must use the greenhouse analogy and yet simultaneously emphasize the relations and attributes highlighted and hidden in the analogy during evaluation., Author(s): Jun-Young Oh [sup.1] , Eui Chan Jeon [sup.2] Author Affiliations: (1) Hanyang University, 0000 0001 1364 9317, grid.49606.3d, , 04763, Seoul, Republic of Korea (2) Department of Environment and [...]