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Temperature stability of the piezoelectric ceramics is critical to its performance in high-power devices. In this research, 5 mol% BiScO3 (BS) is introduced into 0.05Pb(Mn1/3Sb2/3)O3–Pb(Zr1−xTix)O3 system. The morphotropic phase boundary (MPB) has been re-located by shifting Zr/Ti ratio systematically for the piezoceramic. Optimal piezoelectric properties with piezoelectric coefficient d33 of 341 pC/N, electromechanical coupling factor (kp) of 0.51, and mechanical quality factor Qm value of 859 are obtained in MPB compositions of 0.05BiScO3–0.05Pb(Mn1/3Sb2/3)O3–0.9Pb(Zr45.5Ti54.5)O3 ceramic at room temperature. Furthermore, the addition of BiScO3 effects profoundly on the temperature dependence of the piezoelectric and ferroelectric properties. Comparing to common Pb(Zr, Ti)O3-based piezoceramic, the BS-doped ceramic presents elevating ferroelectric polarization with temperature up to 200 °C, as well as stabilized d33, kp, and Qm values from room temperature to 120 °C. [ABSTRACT FROM AUTHOR]

Rare earth elements are greatly valued for their crucial role in many high-tech fields. Highly sensitive and precise determination technology of these elements in aqueous solution is essential for the extraction and recycling processes of these elements. Currently, conventional measurement methods for rare earth elements, such as ICP-MS and ICP-OES, often suffer from issues related to complex operations, lengthy procedures, and low economic efficiency. While laser-induced breakdown spectroscopy (LIBS) provides fast and convenient detection capability, due to the matrix effect of the water LIBS technology itself, the reported sensitivities of these elements have not met the application requirements for detection capabilities. In this work, we propose a method that utilizes a micro-hole array sprayer to rapidly prepare rare earth aqueous solution samples into densely and uniformly adhered particles on an Al substrate, combined with a computer-controlled three-dimensional displacement platform to facilitate fully automated LIBS detection. Through optimization of system parameters, the detection limits for La, Pr, Nd, and Sm reach 8.6, 22.3, 13.6, and 6 μg L−1, respectively, with a stable repeatability of 4.96%, within a total sample preparation and detection time of no more than 15 minutes. Compared to existing LIBS-based detection methods, the average detection limits have been reduced by two orders of magnitude, essentially meeting the ppb-level requirements for practical production. This demonstrates the potential of our system to develop into a fast, low-cost, standardized detection technology in the field of rare earth element exploration, mining, and recovery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Over the course of evolution, plants have developed various sophisticated defense mechanisms to resist pests and diseases. The phytohormone abscisic acid (ABA) has an important role in the growth and development of plants and confers tolerance to selected abiotic stressors, such as drought. Previous studies have shown that ABA promotes the deposit of callose in response to piercing/sucking insect pests. The English grain aphid, Sitobion avenae Fabricius, causes huge losses in rice and is especially harmful to rice seedlings. RESULTS: Exogenous ABA promoted growth and reduced the feeding behavior of S. avenae nymphs in rice. Our results suggested that enhanced trichome density and increased expression of related genes may be associated with rice resistance to aphids. An analysis of volatiles revealed the production of seven compounds associated with pest resistance. CONCLUSION: These results indicate that ABA reduces aphid feeding in rice. Our findings provide a basis for understanding ABA‐mediated defense responses in rice and provide insights on more environmentally‐friendly approaches to control. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

α-RuCl3, a narrow-band Mott insulator with a large work function, offers intriguing potential as a quantum material or as a charge acceptor for electrical contacts in van der Waals devices. In this work, we perform a systematic study of the optical reflection contrast of α-RuCl3 nanoflakes on oxidized silicon wafers and estimate the accuracy of this imaging technique to assess the crystal thickness. Via spectroscopic micro-ellipsometry measurements, we characterize the wavelength-dependent complex refractive index of α-RuCl3 nanoflakes of varying thickness in the visible and near-infrared. Building on these results, we simulate the optical contrast of α-RuCl3 nanoflakes with thicknesses below 100 nm on SiO2/Si substrates under different illumination conditions. We compare the simulated optical contrast with experimental values extracted from optical microscopy images and obtain good agreement. Finally, we show that optical contrast imaging allows us to retrieve the thickness of the RuCl3 nanoflakes exfoliated on an oxidized silicon substrate with a mean deviation of −0.2 nm for thicknesses below 100 nm with a standard deviation of only 1 nm. Our results demonstrate that optical contrast can be used as a non-invasive, fast, and reliable technique to estimate the α-RuCl3 thickness. [ABSTRACT FROM AUTHOR]

With the development of educational technologies, electronic books (e-books) have been improved and adapted to cater to new teaching models, as well as to overcome several challenges reported by printed book portability. The literature about the benefits of e-books in education is still fragmented as several studies have reported distinct disadvantages in addition to advantageous of using them. Currently, no prior study has systematically reviewed the research on the ways e-books have been employed in education and the associated benefits and challenges. To address this gap, this study conducts a systematic review of 123 empirical studies on e-books in education. The findings show that the development and adoption of e-books by countries vary, calling for more international collaborations to facilitate the adoption of e-books worldwide. Additionally, several challenges of e-books were identified, such as eye fatigue and lack of knowledge on using e-books in education by both students and teachers. Therefore, it is suggested that more design strategies and training about using e-books can be conducted to enhance both teaching and learning experiences. Finally, it is argued that future research may focus on designing intelligent and open e-books to expand their use in different contexts and provide more personalized learning. [ABSTRACT FROM AUTHOR]

Developing highly efficient and low-cost hydrogen evolution reaction (HER) electrocatalysts is an urgent and important task for development of green water electrolysis hydrogen production technology. In this work, the nanostructured MoSe2/NiSe2 electrocatalyst with heterojunctions is constructed by a two-step hydrothermal method for HER coupling urea oxidation reaction (UOR). The presence of heterojunctions accelerates the charge transfer and enhances the conductivity of electrocatalysts; thus, the as-prepared nanostructured MoSe2/NiSe2 exhibits bifunctional electrocatalytic activity. Low overpotentials of 79 and 120 mV are required to achieve 10 mA cm–2 current density for the HER and UOR, respectively. For the two-electrode urea electrolysis containing 1 M KOH and 0.5 M urea, a voltage of only 1.47 V is required to deliver the current density of 10 mA cm–2. Density functional theory (DFT) calculation results show that the MoSe2/NiSe2 electrocatalyst can optimize the adsorption of H* and improve the HER activity because of the existence of the heterostructure. This work provides a promising potential for designing energy-saving hydrogen evolution catalysts with alternative electrode reactions. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 reduction reaction (ECO2RR) converts CO2 to high-value chemical products and promotes the carbon cycle. Sulfur (S)-modified copper (Cu) and bismuth (Bi)-based catalysts have been recognized as promising catalysts for ECO2RR. Both of them are highly active for selective formate generation, however, their poor stability and severe competing hydrogen evolution reaction (HER) remain challenging. Herein, S-doped Cu coated with Bi (Bi/Cu-S) is developed to improve ECO2RR selectivity to formate. Bi/Cu-S/brass mesh (BM) electrode material for ECO2RR was prepared by electrodepositing Bi on the surface of Cu-S/BM nanowires obtained from CuS/BM after the electroreduction. The Faradaic efficiency (FE) of the formate reaches the maximum of 94.3% at −0.9 V vs. reversible hydrogen electrode (RHE) with a partial current density as high as −50.7 mAcm−2 and a yield of 30.7 mmolh−1cm−2 under 0.5 M KHCO3 electrolyte. Meanwhile, the FE of formate is higher than 90% in the voltage range of −0.8 to −1.0 V vs. RHE. It also shows good stability at −0.9 V vs. RHE with the FE of formate remaining above 93% after a 10 h reaction. Density functional theory (DFT) calculations demonstrate that the Bi/Cu-S structure promotes the adsorption of CO2 and effectively inhibits HER by enhancing the adsorption of *H to a great extent, improving the selective conversion of CO2 to formate. This work deepens the understanding of the mechanism of Cu-Bi-based catalysts and S-modified Cu-based catalysts in selective ECO2RR to formate, and also provides a new strategy for catalyst design. [ABSTRACT FROM AUTHOR]