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[Display omitted] • We prepared BVO@VO with dual-phase heterostructure. • The heterostructure enables rapid de/insertion of Zn2+ ions. • The Zn2+ diffusion rate in BVO@VO exceeds VO 2 by three orders of magnitude. • The BVO@VO presents a capacity retention of 96% after 2000 cycles at 2.0 A g−1. • The obtained all-solid-state pouch cell shows excellent electrochemical performance. Rechargeable aqueous zinc ion batteries (ZIBs) have emerged as a promising alternative to lithium-ion batteries due to their inherent safety, abundant availability, environmental friendliness and cost-effectiveness. However, the cathodes in ZIBs encounter challenges such as structural instability, low capacity, and sluggish kinetics. In this study, we constructed BiVO 4 @VO 2 (BVO@VO) heterojunction cathode material with bismuth vanadate and vanadium dioxide phases for ZIBs, which demonstrate significant advancements in both aqueous and quasi-solid-state ZIBs. Benefitting from the heterojunction structure, the materials present a high capacity of 262 mAh g−1 at 0.1 A g−1, superb cyclic stability with 96% capacity retention after 1000 cycles at 2 A g−1, and outstanding rate property with a specific capacity of 218 mAh g−1 even at a high rate of 5.0 A g−1. Furthermore, the flexible quasi-solid-state ZIBs incorporating the BVO@VO cathode demonstrate prolonged cyclic life performance with a remarkable specific capacity of 234 mAh g−1 over 100 cycles at a current density of 0.1 A g−1. This study potentially paves the way for the utilization of heterointerface-enhanced zinc ion diffusion for vanadium-based materials in ZIBs, thereby providing a new approach for the design and investigation of high-performance zinc-ion systems. [ABSTRACT FROM AUTHOR]

In this article, the magnetic energy harvester (MEH) based on the current transformer is an innovative method to provide a potential solution for the power supply of sensor networks. Due to the current fluctuation and nonlinearity of the core, the harvester may produce insufficient power at low primary currents, while the core saturates at high primary currents. Aiming at resolving this problem, a novel method is proposed to improve the performance of MEH. In this method, a capacitor and two switches are used to store energy and modulate the core saturation. The performed analyses demonstrate that the proposed method enhances the harvested power under different primary current and load conditions. This is especially more pronounced at low primary currents and loads. It is found that for a low primary current of 2 Arms at 50 Hz, the harvested power increases by 206%. Moreover, applying this method can also reduce the load voltage by controlling the alternating on–off of the switches, thereby protecting the harvester in case of high primary currents. The theoretical calculation, circuit simulation, and experimental results demonstrate the effectiveness of this method. [ABSTRACT FROM AUTHOR]

Ultrasound imaging has developed into an indispensable imaging technology in medical diagnosis and treatment applications due to its unique advantages, such as safety, affordability, and convenience. With the development of data information acquisition technology, ultrasound imaging is increasingly susceptible to speckle noise, which leads to defects, such as low resolution, poor contrast, spots, and shadows, which affect the accuracy of physician analysis and diagnosis. To solve this problem, we proposed a frequency division denoising algorithm combining transform domain and spatial domain. First, the ultrasound image was decomposed into a series of sub-modal images using 2D variational mode decomposition (2D-VMD), and adaptively determined 2D-VMD parameter K value based on visual information fidelity (VIF) criterion. Then, an anisotropic diffusion filter was used to denoise low-frequency sub-modal images, and a 3D block matching algorithm (BM3D) was used to reduce noise for high-frequency images with high noise. Finally, each sub-modal image was reconstructed after processing to obtain the denoised ultrasound image. In the comparative experiments of synthetic, simulation, and real images, the performance of this method was quantitatively evaluated. Various results show that the ability of this algorithm in denoising and maintaining structural details is significantly better than that of other algorithms. [ABSTRACT FROM AUTHOR]

A new high-entropy monoboride (Mo 0.2 Ta 0.2 Ni 0.2 Cr 0.2 W 0.2)B ceramic with a WB-type orthogonal structure was designed and synthesised by in-situ reactive hot pressing at 2000 °C and 30 MPa for 1.5 h under an argon atmosphere. The microstructure of the sintered samples was comprehensively characterised, and the formation of a high-entropy monoboride (Mo 0.2 Ta 0.2 Ni 0.2 Cr 0.2 W 0.2)B ceramic was confirmed. Owing to the high density of the dislocations and strengthening metal-boron bonds, the high-entropy (Mo 0.2 Ta 0.2 Ni 0.2 Cr 0.2 W 0.2)B ceramic exhibited a hardness of 48.51 ± 4.07 GPa, which enabled it to be classed as a new superhard material. In addition, the thermal conductivity (2.05 ± 0.10 W/(m·K) at 400 °C) and electric conductivity (132.30 S/cm) were determined. [ABSTRACT FROM AUTHOR]

Objective. To explore altered regional neuronal activity in patients with nonarteritic anterior ischemic optic neuropathy (NAION) and its correlation with clinical performances using the regional homogeneity (ReHo) method, which is based on resting-state functional magnetic resonance imaging (fMRI). Method. Thirty-one patients with NAION (20 males, 11 females) and 31 age- and sex-matched normal controls (NCs) (20 males, 11 females) were enrolled in the study. All patients underwent ophthalmic examination, including eyesight, intraocular pressure measurement, optimal coherence tomography (OCT), visual field analysis, and fMRI scans. After ReHo was calculated, we investigated group differences in results between the patients and NCs. We analyzed the relationship between ReHo values for different brain regions in patients with NAION and intraocular pressure, visual field analysis, and OCT. A receiver operating characteristic (ROC) curve was used to assess the diagnostic ability of the ReHo method. Results. Compared with NCs, patients with NAION exhibited higher ReHo values in the left middle frontal gyrus, left middle cingulate gyrus, left superior temporal gyrus, and left inferior parietal lobule. Additionally, they exhibited lower ReHo values in the right lingual gyrus, left putamen/lentiform nucleus, and left superior parietal lobule. ReHo values in the left superior parietal lobule were negatively correlated with right retinal nerve fiber layer values (r = − 0.462 , P = 0.01). The area under the ROC curve for each brain region indicated that the ReHo method is a credible means of diagnosing patient with NAION. Conclusion. NAION was primarily associated with dysfunction in the default mode network, which may reflect its underlying neural mechanisms. [ABSTRACT FROM AUTHOR]

Accurate identification and understanding of various metallic minerals are crucial for deciphering geological formations, structures, and ages. Giving their pivotal role as essential natural resources, a microscopic exploration of metallic minerals becomes imperative. Traditional analytical methods, while helpful, exhibit certain limitations. However, terahertz time-domain spectroscopy, distinguished by its high signal-to-noise ratio, expansive frequency band, and low incident wave energy, is a promising complement to conventional techniques in characterizing metallic minerals. This study employs terahertz time-domain spectroscopy to examine samples of Stibnite, Sphalerite, Galena, and Pyrite originating from diverse geological conditions. The vibrations of molecules within these metallic minerals induce discernible changes in the terahertz spectra. Our findings untiate the extensive potential of terahertz time-domain spectroscopy in the characterization of metallic minerals, affirming its considerable practical value in mineral resource exploration. [ABSTRACT FROM AUTHOR]

High-entropy monoborides (HEMBs) are promising materials for use in cutting tools and wear-resistant coatings owing to their super hardness. Because of the scarcity of reports on powder synthesis, extensive application of HEMBs is limited. To address this problem, a molten-salt-assisted strategy for synthesising HEMB powders is proposed herein. High-entropy (V 0.2 Cr 0.2 Mo 0.2 W 0.2 Ni 0.2)B powders with CrB-type orthogonal crystal structures were successfully synthesised at 1500 °C and examined by using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Subsequently, the mechanism of powder synthesis using molten salt and the advantages of powders prepared by employing molten salt for the densification and hardness enhancement of ceramics were comprehensively evaluated. The (V 0.2 Cr 0.2 Mo 0.2 W 0.2 Ni 0.2)B powders were densified by applying spark plasma sintering to study the microstructural evolution of bulk ceramics with a super hardness of 42.19 ± 2.66 GPa. This work has expanded the family of superhard HEMBs and provides a strong support for the further application of HEMBs. • High-entropy (V 0.2 Cr 0.2 Mo 0.2 W 0.2 Ni 0.2)B powder was synthesized assisted by molten salt for the first time. • High-entropy (V 0.2 Cr 0.2 Mo 0.2 W 0.2 Ni 0.2)B ceramic with hardness of 42.19 ± 2.66 GPa was successfully prepared. • The corresponding molten salt assisted mechanism was analyzed thought a reasonable hypothesis. [ABSTRACT FROM AUTHOR]

Cofiring sludge with coal based on existing power plants is a promising method to realize harmless recycling treatment for sludge disposal. However, the influences of sludge addition on NOx emission are still controversial. Moreover, the optimal operating strategies for the cocombustion boiler need further investigations. In this study, the influences of sludge blending ratio, moisture content, sludge inlet position, and air-staging parameter on the combustion characteristics and NOx emission behaviors in a 330-MW boiler were analyzed numerically. The results show that with the increase of sludge blending ratio, the flue gas temperature in the primary zone decreases. The overall burnout ratio declines with the addition of sludge due to the higher ash and moisture contents. Although the sludge contains more N than coal, the NOx emissions in the cofiring case are lower than those in the coal-fired case due to the lower temperature and stronger reducing atmosphere in the primary zone. Reducing the moisture in the sludge is beneficial to the combustion within the furnace. Nevertheless, because of the higher temperature and lower CO concentration within the furnace, the NOx concentration at the furnace outlet increases. For wall-fired boilers, feeding the sludge from the lower burners should be avoided considering the potential surge in NOx emission. When the excess air ratio in the primary zone increases from 0.74 to 0.96, the NOx concentration at the furnace outlet rises by 58%. Hence, although relatively lower excess air ratio in the primary zone could bring adverse impacts on the burnout behaviors, air-staging combustion is still necessary when cofiring sludge in the coal-fired boiler. [ABSTRACT FROM AUTHOR]

Geolocation is a fundamental component of route planning and navigation for unmanned vehicles, but GNSS-based geolocation fails under denial-of-service conditions. Cross-view geo-localization (CVGL), which aims to estimate the geographic location of the ground-level camera by matching against enormous geo-tagged aerial (e.g., satellite) images, has received a lot of attention but remains extremely challenging due to the drastic appearance differences across aerial–ground views. In existing methods, global representations of different views are extracted primarily using Siamese-like architectures, but their interactive benefits are seldom taken into account. In this paper, we present a novel approach using cross-view knowledge generative techniques in combination with transformers, namely mutual generative transformer learning (MGTL), for CVGL. Specifically, by taking the initial representations produced by the backbone network, MGTL develops two separate generative sub-modules—one for aerial-aware knowledge generation from ground-view semantics and vice versa—and fully exploits the entirely mutual benefits through the attention mechanism. Moreover, to better capture the co-visual relationships between aerial and ground views, we introduce a cascaded attention masking algorithm to further boost accuracy. Extensive experiments on challenging public benchmarks, i.e., CVACT and CVUSA, demonstrate the effectiveness of the proposed method, which sets new records compared with the existing state-of-the-art models. Our code will be available upon acceptance. [ABSTRACT FROM AUTHOR]

Pervaporation membranes have exhibited great potential for desalinating brine solutions. However, the flux recovery after membrane washing and the membrane's resistance to chemical cleaning reagents were barely studied. Our group has reported excellent desalination properties of PVA based pervaporation membranes. Nevertheless, the membranes were damaged during chemical cleaning due to the poor chlorine resistance of PVA. In this study, the more active 1, 2-diol units of PVA were removed by sodium periodate treatment. And then, the modified PVA was crosslinked by FS-3100, a fluorocarbon based crosslinker, to improve its hydrostability and chlorine resistance. The FS-3100 crosslinked composite (PVA-FS/PVDF) showed a water flux of 34 ± 1 kg m−2 h−1 with a NaCl rejection of 99.93% when desalinated a 35000 ppm NaCl solution at 70 °C. Salt rejections were maintained after soaking in 2000 ppm NaClO, acid (pH = 2), and alkali (pH = 12) solutions for 168, 180, and 180 h, respectively. A long term desalination experiment was carried out using Tween 20 and HA as foulants. The water fluxes could be recovered to 100% after chemical washing without losing salt rejections, indicating an excellent long term operation stability of the FS-3100 crosslinked PV membranes. PVA with superior chemical resistance is obtained by crosslinked with fluorocarbon containing chemical. Image 1 • 1, 2-diols of PVA were removed to improve chlorine resistance. • The PVA was further crosslinked by FS-3100. • The crosslined PVA membrane had superior tolerance to acid, alkali, and chlorine. • Membrane flux could be recovered 100% after chemical washing. [ABSTRACT FROM AUTHOR]

As a typical ceramic tool, the wear resistance of Al 2 O 3 /SiC w composites is a prominent parameter in engineering applications. Therefore, how to improve its wear resistance has becomes a research emphasis of ceramic tools. In this work, the Al 2 O 3 /SiC w composites with improved wear resistance were prepared by a novel oscillatory pressure-assisted sinter forging (OPSF) process. The composites prepared by OPSF process not only exhibit higher density and significantly improved mechanical properties, but also own lower coefficient of friction than conventional sinter forging and hot oscillatory pressing processes. EBSD results indicated that the OPSF process could improve the texture of (0001) crystal face, low-angle grain boundaries, high-angle grain boundaries with special angles in the Al 2 O 3 matrix and enhance shear deformation at micro-scales, which are multiple contributed to enhanced wear resistance. Therefore, OPSF process is a promising technique to prepare ceramic-based cutting tools with excellent mechanical properties and wear resistance. [ABSTRACT FROM AUTHOR]

We studied the chaotic peculiarities of magnetic-mechanical coupled system of GMA. Based on the working principle of GMA and according to Newton's second law of motion, first piezomagnetic equation, disk spring design theory, and structural dynamics principle of GMA, the present study established a GMA magnetic-mechanical coupled system model. By carrying out data modeling of this coupled system model, the bifurcation chart of the system with the variation of damping factor, excitation force, and exciting frequency parameters as well as the homologous offset oscillogram, phase plane trace chart, and Poincaré diagram was obtained, and the chaotic peculiarities of the system were analyzed. The influence of parametric errors on the coupled system was studied. The analytical results showed that the oscillation equation of the GMA magnetic-mechanical coupled system had nonlinearity and the movement morphology was complicated and diversified. By adjusting the damping factor, exciting frequency, and excitation force parameters of the system, the system could work under the stable interval, which provided theoretical support for the stability design of GMA. [ABSTRACT FROM AUTHOR]

This study systematically investigated the variable main electrooxidation mechanism of chlorophene (CP) and dichlorophen (DCP) with the change of reaction conditions at Ti 4 O 7 anode operated in batch and reactive electrochemical membrane (REM) modes. Significant degradation of CP and DCP was observed, that is, CP exhibited greater removal efficiency in batch mode at 0.5–3.5 mA cm−2 and REM operation (0.5 mA cm−2) with a permeate flow rate of 0.85 cm min−1 under the same reaction conditions, while DCP exhibited a faster degradation rate with the increase of current density in REM operation. Density functional theory (DFT) simulation and electrochemical performance tests indicated that the electrooxidation efficiency of CP and DCP in batch mode was primarily affected by the mass transfer rates. And the removal efficiency when anodic potentials were less than 1.7 V vs SHE in REM operation was determined by the activation energy for direct electron transfer (DET) reaction, however, the adsorption function of CP and DCP on the Ti 4 O 7 anode became a dominant factor in determining the degradation efficiency with the further increase of anodic potential due to the disappeared activation barrier. In addition, the degradation pathways of CP and DCP were proposed according to intermediate products identification and frontier electron densities (FEDs) calculation, the acute toxicity of CP and DCP were also effectively decreased during both batch and REM operations. [Display omitted] • Evident degradation of CP and DCP was achieved during both batch and REM modes. • Electrooxidation efficiency in batch mode was limited by the mass transfer rates. • DET reaction was the main electrooxidation mechanism at low anodic potential. • Adsorption energy was key factor during REM treatment at higher anodic potential. • REM treatment exhibited more advantages to reduce ecological risks of CP or DCP. [ABSTRACT FROM AUTHOR]