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Achieving a large adiabatic temperature change (ΔT) and broadening the operating temperature span (Tspan) are two main challenges in modulating the electrocaloric (EC) effect of relaxor ferroelectrics. Here, synergistic optimization has been achieved through creating multi-stage phase transitions in layered sodium bismuth titanate (BNT)-based ceramics. A direct measurement indicates that the strategy achieves a large EC response (ΔT >1 K within a Tspan of 66 °C). The cooling performance exceeds 90% and 80% of the maximum for temperature spans of 44 °C and 67 °C, respectively, demonstrating excellent temperature stability. Additionally, the difference in dielectric permittivity (ε) among ceramic layers creates an uneven distribution of the electric field (E), with their EC effects adaptively compensating for each other with temperature, thereby further enhancing the stability. The novel design strategy and optimization mechanism proposed in this work will guide the development of high-performance EC materials with a wide operating temperature span. [ABSTRACT FROM AUTHOR]

Fatty liver is characterized by the expansion of lipid droplets (LDs) and is associated with the development of many metabolic diseases. We assessed the morphology of hepatic LDs and performed quantitative proteomics in lean, glucose-tolerant mice compared with high-fat diet (HFD) fed mice that displayed hepatic steatosis and glucose intolerance as well as high-starch diet (HStD) fed mice who exhibited similar levels of hepatic steatosis but remained glucose tolerant. Both HFD- and HStD-fed mice had more and larger LDs than Chow-fed animals. We observed striking differences in liver LD proteomes of HFD- and HStD-fed mice compared with Chow-fed mice, with fewer differences between HFD and HStD. Taking advantage of our diet strategy, we identified a fatty liver LD proteome consisting of proteins common in HFD- and HStD-fed mice, as well as a proteome associated with glucose tolerance that included proteins shared in Chow and HStD but not HFD-fed mice. Notably, glucose intolerance was associated with changes in the ratio of adipose triglyceride lipase to perilipin 5 in the LD proteome, suggesting dysregulation of neutral lipid homeostasis in glucose-intolerant fatty liver. We conclude that our novel dietary approach uncouples ectopic lipid burden from insulin resistance-associated changes in the hepatic lipid droplet proteome. NEW & NOTEWORTHY: This study identified a fatty liver lipid droplet proteome and one associated with glucose tolerance. Notably, glucose intolerance was linked with changes in the ratio of adipose triglyceride lipase to perilipin 5 that is indicative of dysregulation of neutral lipid homeostasis. [ABSTRACT FROM AUTHOR]

Two-dimensional phase unwrapping (2-D PU) is vital for reconstructing Earth's surface topography and displacement from interferometric synthetic aperture radar (InSAR) data. Conventional algorithms rely on the postulate, but this assumption is often insufficient due to abrupt topographic changes and severe noise. To address this challenge, our research proposes a novel approach utilizing deep convolutional neural networks inspired by the U-Net architecture to estimate phase gradient information. Our approach involves downsampling the input data to extract crucial features, followed by upsampling to restore spatial resolution. We incorporate two attention mechanisms—feature pyramid attention (FPA) and global attention upsample (GAU)—and a residual structure in the network's structure. Thus, we construct ResDANet (residual and dual attention net). We rigorously train ResDANet utilizing simulated datasets and employ an L1-norm objective function to minimize the disparity between unwrapped phase gradients and those calculated by ResDANet, yielding the final 2-D PU results. The network is rigorously trained using two distinct training strategies and encompassing three types of simulated datasets. ResDANet exhibits excellent robust performance and efficiency on simulated data and real data, such as China's Three Gorges and an Italian volcano. [ABSTRACT FROM AUTHOR]

The phase transition temperature (e.g., that of orthorhombic‐tetragonal TO‐T) of relaxor ferroelectrics are commonly obtained through electrical method (i.e., temperature dependence of dielectric constant), and the samples need to be coated with metal electrode and tested by a sophisticated impedance analyzer. This contact measuring method is inefficient, inconvenient and easy to damage the sample surface, inapplicable to transparent ferroelectrics. Here, we successfully fabricated Bi/Sm co‐doped K0.5Na0.5NbO3 transparent ceramics with photoluminescent behavior and relaxor‐like ferroelectricity, which simultaneously realized TO‐T monitoring and temperature sensing via fluorescence intensity ratio (FIR) technology. This simple, rapid, noncontact and nondestructive optical way displays small TO‐T deviation (merely 0.78%) compared to the electrical method. And the temperature‐dependent optical characteristics and coercive electric field all present abrupt changes, whose abnormal temperature regions are in accordance with that around TO‐T. In addition, the maximum absolute sensitivity and relative sensitivity of the ceramics reach 0.0072 K−1 (at 533 K) and 0.0111 K−1 (at 453 K), respectively, exhibiting superior optical temperature sensing performance. The tactical use of FIR technology is of great significance for widening the applications of luminescent‐ferroelectric transparent ceramics. [ABSTRACT FROM AUTHOR]

Enhancing the energy storage performance of dielectric material through the adoption of a novel domain strategy is highly desirable. In this study, Bi0.5Na0.5TiO3‐based thin films are fabricated with topological vortex domains (VDs) by controlling the grain size and investigated the correlation between these VDs and the macroscopic polarization response, which is crucial for the energy storage performance. The emergence of VDs, in contrast to conventional ferroelectric domains, promotes polarization reversal in dielectric materials. Additionally, in contrast to the severely reduced saturation polarization typically noted in conventional relaxor ferroelectrics (RFE), the presence of VDs in RFE leads to only a slight reduction in saturation polarization. These two advantages contribute to the superior energy storage performance of the films with VDs. This approach offers a novel and promising direction for developing dielectrics with high‐energy storage capabilities. [ABSTRACT FROM AUTHOR]

Traditional solid‐state luminescent materials (e.g., phosphors and microcrystalline glasses) have attracted extensive attention due to their high energy efficiency and long lifespan. However, their application scope is limited by complex compositions and manufacturing processes, as well as single‐function. In this study, solid‐state reaction was utilized to prepare transparent‐ferroelectric (K0.5Na0.5)NbO3 (KNN) ceramics by simply codoping with Dy3+ and Sr2+, providing possibilities for large‐scale production. Ceramics exhibit high optical transmittance, high‐quality white‐light emission and relaxor ferroelectric feature. Under irradiation of UV light, photochromic behavior occurring in the ceramics, resulting in modulating the optical performances, especially quality of emitted white light. Multifunctionality can expand latent applications of KNN‐based ceramics from white light‐emitting diodes to modulated optoelectronic devices. [ABSTRACT FROM AUTHOR]

The family of rare-earth doped phosphors has drawn pronounced attention in technological of fingerprint visualization, anti-counterfeiting, and phosphor-converted light-emitting diodes applications. A series of NaSrGd(1–x–y)EuxDyy(WO4)3 powder luminescent materials were synthesized by a solid-state reaction. The emission color of NaSrGd(WO4)3:Dy3+ phosphor could be tunned via changing concentrations of Eu3+ ion. In addition, the phosphors exhibit narrow red-light emission at 610 nm caused by the electric dipole transition 5D0 → 7F2 of Eu3+. Especially, the phosphor exhibits superior thermal stability, its emission intensity of optimum sample remained ± 15% over the temperature range from 233 to 393 K. The Commission International de I'Eclairage (CIE) chromaticity coordinates of x = 0.4 are (0.6388, 0.3371) with a high color purity (92.84%). More importantly, prepared color-changing device of phosphors achieves a high level of optical safety. The results demonstrate that their materials can be potentially applied to the field of white light-emitting diodes (LEDs) and optical anti-counterfeiting. [ABSTRACT FROM AUTHOR]

The development of high‐performance (K,Na)NbO3 (KNN)‐based lead‐free piezoceramics for next‐generation electronic devices is crucial for achieving environmentally sustainable society. However, despite recent improvements in piezoelectric coefficients, correlating their properties to underlying multiscale structures remains a key issue for high‐performance KNN‐based ceramics with complex phase boundaries. Here, this study proposes a medium‐entropy strategy to design "local polymorphic distortion" in conjunction with the construction of uniformly oversize grains in the newly developed KNN solid‐solution, resulting in a novel large‐size hierarchical domain architecture (≈0.7 µm wide). Such a structure not only facilitates polarization rotation but also ensures a large residual polarization, which significantly improves the piezoelectricity (≈3.2 times) and obtains a giant energy harvesting performance (Wout = 2.44 mW, PD = 35.32 µW mm−3, outperforming most lead‐free piezoceramics). This study confirms the coexistence of multiphase through the atomic‐resolution polarization features and analyzes the domain/phase transition mechanisms using in situ electric field structural characterizations, revealing that the electric field induces highly effective multiscale polarization configuration transitions based on T–O–R sequential phase transitions. This study demonstrates a new strategy for designing high‐performance piezoceramics and facilitates the development of lead‐free piezoceramic materials in energy harvesting applications. [ABSTRACT FROM AUTHOR]