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The use of water‐soluble sacrificial layer of Sr3Al2O6 has tremendously boosted the research on freestanding functional oxide thin films, especially thanks to its ultimate capability to produce high‐quality epitaxial perovskite thin films. However, the costly single‐crystalline substrates, e.g., SrTiO3, are generally discarded after obtaining the freestanding thin films. Here, it is demonstrated that the SrTiO3 substrates can be recycled to fabricate La0.7Sr0.3MnO3 films with nearly identical structural and electrical properties. After attaining freestanding thin films, the residues on SrTiO3 can be removed by 80 °C hot water soaking and rinsing treatments. Consequently, the surface of SrTiO3 reverted to its original step‐and‐terrace structure. [ABSTRACT FROM AUTHOR]

Misinformation is a complex and urgent sociotechnical problem that requires meaningful governance, in addition to technical efforts aimed at detection or classification and intervention or literacy efforts aimed at promoting awareness and identification. This review draws on interdisciplinary literature—spanning information science, computer science, management, law, political science, public policy, journalism, communications, psychology, and sociology—to deliver an adaptable, descriptive governance model synthesized from past scholarship on the governance of misinformation. Crossing disciplines and contexts of study and cases, we characterize: the complexity and impact of misinformation as a governance challenge, what has been managed and governed relative to misinformation, the institutional structure of different governance parameters, and empirically identified sources of success and failure in different governance models. Our approach to support this review is based on systematic, structured literature review methods to synthesize and compare insights drawn from conceptual, qualitative, and quantitative empirical works published in or translated into English from 1991 to the present. This review contributes a model for misinformation governance research, an agenda for future research, and recommendations for contextually‐responsive and holistic governance. [ABSTRACT FROM AUTHOR]

La 0·7 Ca 0.3− x Sr x MnO 3 :Ag 0.2 (LCSMO:Ag) ceramics with varying strontium (Sr) content (x = 0.0165, 0.03, 0.05, 0.07, and 0.1) were synthesized using a combination of sol–gel and solid-state doping methods and studied as colossal magnetoresistance materials. Significant improvements in the peak temperature coefficient of resistivity (TCR) and resistivity (ρ) were observed across all ceramic samples when the mol% of Sr was adjusted. The low ρ and large TCR values resulted from a combination of two factors. First, the presence of Sr led to the increase in the grain size and decrease in the number of boundaries, which improved the electrical transport and reduced the boundary scattering effects. This resulted in additional improvement in the grain arrangement order. Second, the cell volume (V cell) and octahedron volume (V oct) both decreased first and then increased. The MnO 6 octahedron underwent gradual deformation into a flattened shape, which facilitated carrier migration and increased electrical sensitivity of the material. The ceramic with x = 0.03 maintained high and stable TCR values in different working environments, both without a magnetic field (TCR o , 54.76% K−1) and in the presence of a vertical field (TCR ⊥ , 33.33% K−1). Furthermore, the material exhibited a low resistivity and a higher insulator–metal transition temperature (T p). Performance differences among the samples were comprehensively and systematically explained by conducting cross magnetic field tests with field directions parallel and perpendicular to the flat surface of the bulk material, respectively. Overall, the findings of this study indicate that these ceramics act as promising candidates for future applications in information storage devices and magnetic sensors. [ABSTRACT FROM AUTHOR]

In order to obtain high temperature coefficient of resistance (TCR) value of La0.67Ca0.33MnO3:Agx (LCMO:Agx) composites, samples with different Ag contents (x = 0, 0.1, 0.2, 0.25, 0.3, and 0.5) were prepared by sol-gel method. X-ray diffraction analyses indicated that all samples had orthorhombic perovskite structures. As x increased, lattice parameters (a, b, c) and cell volumes underwent slight expansions. Interestingly, the addition of Ag dramatically affected TCR and magneto-resistance (MR) values. Elevated TCR value up to 53.46%·K−1 at 277 K was observed for LCMO:Agx composites with added Ag at the composition of x = 0.1. Meanwhile, MR value at 263 K reached 71% at the magnetic field of 1 T for samples with Ag composition of x = 0.25. The increase in Mn4+/Mn3+ ratio and improvement in crystallization caused by added Ag was found responsible for the elevated values of TCR, MR, and Tp. These findings may have practical use in high-performance magneto-resistive manganites. [ABSTRACT FROM AUTHOR]