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Epitaxial growth of complex oxides on large-area wafers, such as sapphire and silicon, represents a key step toward scalable oxide device production. Solid phase epitaxy allows the synthesis of γ-Al2O3 on α-Al2O3 and provides a template with a matched lattice constant and appropriate cubic symmetry for subsequent heteroepitaxial growth of perovskite complex oxides. Nb-doped SrTiO3 thin films were deposited epitaxially on (111)-oriented γ-Al2O3 intermediate layers on (0001) c-axis-oriented sapphire α-Al2O3 crystals using pulsed laser deposition. The Nb:SrTiO3 thin films with a thickness of 53 nm, grown at 700 °C on γ-Al2O3, reached fully relaxed lattice parameters and were epitaxially oriented with respect to the substrate. Nb:SrTiO3 layers deposited using identical deposition conditions directly on α-Al2O3, without the γ-Al2O3 intermediate layer, were polycrystalline. The sheet conductivity of Nb:SrTiO3 grown on γ-Al2O3/α-Al2O3 is more than ten times higher than that of Nb:SrTiO3 grown directly on α-Al2O3 without the γ-Al2O3 layer. The results point to new directions for the integration of (111)-oriented pseudocubic perovskite complex oxides and the integration of epitaxial complex oxides over larger areas using α-Al2O3 single-crystal substrates. 

Mn-based Li-ion battery cathodes encompass a great variety of materials structures. Decades of research effort have proven that developing a Mn-based structure featuring a high redox activity, stable cycling, and cost-effectiveness is a longstanding challenge. Motivated by such a need and inspired by the structural diversity of Mn-based cathodes, we develop a partially cation-disordered lithium niobium manganese oxide with a zigzag structure, filling the knowledge gap between zigzag-ordered and fully disordered Li–Mn-based oxides. Electrochemically, the partially disordered cathode greatly unlocks the redox activity of the zigzag lattice and maintains the cycling stability. Mechanism-wise, the partial disordering suppresses the disproportionation reaction of Mn(III) and facilitates a disordered λ-MnO2–tetragonal cation-disordered rock salt structural transformation. The work suggests the substantial opportunity of using partial disordering as the key strategy to revive locked-up redox activities and realize new energy storage mechanisms, for the pursuit of high-performance cost-effective battery materials. 

Overcoming challenges and transitioning from school to work is particularly problematic for individuals who are deaf or hard of hearing, presenting significant issues for both the labor market and vocational training institutions. Due to the lack of research addressing the career maturity and distinctive obstacles faced by this population, this paper endeavors to investigate performance disparities within the machining field. The specific focus is on assessing whether hearing loss may impact students' machining performance. Considering the essential human capabilities for perception in machining, especially in industrial settings, encompass a range of faculties including visualization, hearing, and tactile senses. Thus, addressing concerns related to accommodating individuals with disabilities is important, prompting inquiries into optimizing training programs and quantifying potential disparities in learning or schooling outcomes, behavioral patterns, and overall performance in future careers. The conducted studies involved multiple participants, including hearing, deaf, and hard-of-hearing students with various machining training backgrounds. The investigation will delve into data concerning the qualities of manual machining outputs and the subject’s self-rating feedback. The outcomes from this study are expected not only to allow to obtain more insights into human behavior in machining operations, but also to identify key differences between machinist trainees who exhibit no underlying hearing problems and ones who are deaf/hard of hearing. The findings of this work provide valuable takeaways concerning machinists with hearing loss, revealing little to no effect of hearing loss on trainee performance, alleviating concerns about potential performance weaknesses. The outcomes from this study have shown that trainee experience seems to relate directly to machining proficiency, regardless of hearing loss. 

Abstract Minifilaments are widespread small-scale structures in the solar atmosphere. To better understand their formation and eruption mechanisms, we investigate the entire life of a sigmoidal minifilament located below a large quiescent filament observed by Big Bear Solar Observatory/Goode Solar Telescope on 2015 August 3. The Hαstructure initially appears as a group of arched threads, then transforms into two J-shaped arcades, and finally forms a sigmoidal shape. Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly observations in 171 Å show that two coronal jets occur around the southern footpoint of the minifilament before the minifilament eruption. The minifilament eruption starts from the southern footpoint, then interacts with the overlying filament and fails. The aforementioned observational changes correspond to three episodes of flux cancellations observed by SDO/Helioseismic and Magnetic Imager. Unlike previous studies, the flux cancellation occurs between the polarity where the southern footpoint of the minifilament is rooted and an external polarity. We construct two magnetic field models before the eruption using the flux rope insertion method and find a hyperbolic flux tube above the flux cancellation site. The observation and modeling results suggest that the eruption is triggered by the external magnetic reconnection between the core field of the minifilament and the external fields due to flux cancellations. This study reveals a new triggering mechanism for minifilament eruptions and a new relationship between minifilament eruptions and coronal jets.