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To produce high-performance dielectric capacitors for pulsed power applications, BaTiO3@(MgO–Nb2O5)–xYb2O3 (BT@MNY-x) ceramics were prepared via solid-state reaction route. The BT@MNY ceramics retained tetragonal perovskite structure without other obvious phases. Profound structural tests by Rietveld refinement of XRD patterns verified Yb3+ substituted the Ti4+ sites. In addition, after Yb3+ ions were incorporated into the lattice of barium titanate, the cubic phase of barium titanate was slightly distorted, the lattice constant of the sample gradually increased, and the tetragonality of the sample gradually decreased. With the increase of Yb2O3 content, the porosity and the diffuseness degree (γ) of the ceramics first decreased and then increased, reaching the peak values in the BT@MNY-0.5 sample. In addition, the grain size and dielectric constant of the samples decreased with the increase of Yb2O3 content. As a result, the breakdown voltage of the ceramics and performance metrics such as effective energy storage density first increased and then decreased. The calculated activation energies (Ea = 0.9–1.1 eV) closely resemble those observed for oxygen vacancy conduction activation energy in perovskite systems (around 1 eV), indicating that the conductivity in the BT@MNY ceramics is likely governed by oxygen vacancies. When x = 0.5, environmentally friendly barium titanate-based ceramics with Wrec of 0.82 J/cm3 and η of 44.34% were achieved. This work provides a theoretical basis for high energy storage barium titanate ceramics. [ABSTRACT FROM AUTHOR]

Band structure of a semiconducting film critically determines the charge separation and transport efficiency. In antimony selenosulfide (Sb2(S,Se)3) solar cells, the hydrothermal method has achieved control of band gap width of Sb2(S,Se)3 thin film through tuning the atomic ratio of S/Se, resulting in an efficiency breakthrough towards 10 %. However, the obtained band structure exhibits an unfavorable gradient distribution in terms of carrier transport, which seriously impedes the device efficiency improvement. To solve this problem, here we develop a strategy by intentionally regulating hydrothermal temperature to control the chemical reaction kinetics between S and Se sources with Sb source. This approach enables the control over vertical distribution of S/Se atomic ratio in Sb2(S,Se)3 films, forming a favorable band structure which is conducive to carrier transport. Meanwhile, the adjusted element distribution not only ensures the uniformity of grain structure, but also increases the Se content of the films and suppress sulfur vacancy defects. Ultimately, the device delivers a high efficiency of 10.55 %, which is among the highest reported efficiency of Sb2(S,Se)3 solar cells. This study provides an effective strategy towards manipulating the element distribution in mixed‐anion compound films prepared by solution‐based method to optimize their optical and electrical properties. [ABSTRACT FROM AUTHOR]

The disposal of stone waste derived from the stone industry is a worldwide problem. The shortage of landfills, as well as transport costs and environmental pollution, pose a crucial problem. Additionally, as a substitute for cement that has high carbon emissions, energy consumption, and pollution, the disposal of stone wastes by utilizing solid waste-based binders as road base materials can achieve the goal of "waste for waste". However, the mechanical properties and deterioration mechanism of solid waste-based binder solidified stone waste as a road base material under complex environments remains incompletely understood. This paper reveals the durability performance of CGF all-solid waste binder (consisting of calcium carbide residue, ground granulated blast furnace slag, and fly ash) solidified stone waste through the macro and micro properties under dry–wet and freeze–thaw cycling conditions. The results showed that the dry–wet and freeze–thaw cycles have similar patterns of impacts on the CGF and cement stone waste road base materials, i.e., the stress–strain curves and damage forms were similar in exhibiting the strain-softening type, and the unconfined compressive strengths all decreased with the number of cycles and then tended to stabilize. However, the influence of dry–wet and freeze–thaw cycles on the deterioration degree was significantly different; CGF showed excellent resistance to dry–wet cycles, whereas cement was superior in freeze–thaw resistance. The deterioration grade of CGF and cement ranged from 36.15 to 47.72% and 39.38 to 47.64%, respectively, after 12 dry–wet cycles, whereas it ranged from 57.91 to 64.48% and 36.61 to 40.00% after 12 freeze–thaw cycles, respectively. The combined use of MIP and SEM confirmed that the deterioration was due to the increase in the porosity and cracks induced by dry–wet and freeze–thaw cycles, which in turn enhanced the deterioration phenomenon. This can be ascribed to the fact that small pores occupy the largest proportion and contribute to the deterioration process, and the deterioration caused by dry–wet cycles is associated with the formation of large pores through the connection of small pores, while the freeze–thaw damage is due to the increase in medium pores that are more susceptible to water intrusion. The findings provide theoretical instruction and technical support for utilizing solid waste-based binders for solidified stone waste in road base engineering. [ABSTRACT FROM AUTHOR]

Establishing a strength model for cement-stabilized clayey soils is crucial to the design and construction of cement-reinforced foundation projects. Numerous studies have used the parameters to establish the strength model, but the selection of the key characterization parameters that determine the strength development remains challenging. Therefore, more studies and indoor tests are required to verify the parameters. This study designs cement-stabilized pure clay particles (i.e., kaolin) with various characterization parameters and conducts a series of unconfined compressive strength tests. Using the results from the strength tests to clarify the influence mechanism for the characterization parameters, the strongly correlated characterization parameters were identified with correlation analysis, and these parameters were used to establish a multilinear regression model for strength. The experimental results showed that Pearson's correlation analysis could effectively identify the relationship between the characterization parameters of the soil particles, water, and cement, and the strength of cement-stabilized clayey soils at different curing times and their correlation intensity. The multilinear regression-based strength model was determined based on a strong Pearson's correlation. The predicted value is similar to the measured value, with a correlation coefficient of 0.985, a mean absolute error (MAE) of 163.80 kPa, and the predicted root mean square error (RMSE) of 225.99 kPa. This study's findings could provide theoretical support for the strength design and performance prediction of cement-stabilized clayey soils. [ABSTRACT FROM AUTHOR]

Stone waste refers to the waste stone particles generated from mining and stone processing to finished products that are not utilized in a resourceful manner. In this study, a CGF solid waste-based binder (abbreviated as CGF), with calcium carbide residue (CCR), ground granulated blast-furnace slag (GGBS), and fly ash (FA) as components, was developed to solidify the stone waste. Through "treating waste with waste", the resource utilization of solid waste was realized. In order to improve the performance of the new material, this paper proposes the MAA-SW model for stone waste pavement base material based on the MAA model, establishes the relationship with the target gradation, and obtains the ideal gradation composition of stone waste through the calculation of the response surface analysis so as to obtain an energy-saving stone waste pavement base material with excellent performance. [ABSTRACT FROM AUTHOR]

The influence of northern polar vortex in the stratosphere (SPV) in December‐January on Asia's surface air temperature (SAT) in February has been examined using reanalysis data sets and a barotropic model. An out‐of‐phase interannual linkage between the SPV in December‐January and SAT in February during 1979–2022 has been observed, that is, a strong (weak) SPV corresponds to a cooling (warming) over Asia. Approximately 25% of the SAT over Asia in February can be explained by the SPV in December‐January. This relationship between the SPV and SAT is independent of the Arctic Oscillation. The influence of the SPV on SAT over Asia cannot be solely explained by radiative processes, but is instead related to circulation anomalies in the troposphere. A stronger SPV tends to result in negative geopotential height anomalies with cyclonic circulation over Asia. The SPV‐related geopotential height over Asia is accompanied by a weakened teleconnection pattern between the North Atlantic and Asia, with three centers from the northeastern Atlantic‐eastern Europe‐Asia, and fewer stationary waves propagated from North Atlantic into Asia. These anomalous circulation patterns and anomalous northerly wind over Central Asia in February are beneficial to the colder air transportation from the higher latitudes to Asia, facilitating a surface cooling over Asia. Our results shed light on the interannual linkage between SPV and SAT over Asia, suggesting that the SPV in December‐January could be considered as a new predicator of SAT in February over Asia. Plain Language Summary: Scientists and the public have become increasingly aware of the significant influences of the stratosphere on tropospheric weather and climate. While numerous studies have focused on the crucial roles of stratospheric anomalies in shaping surface air temperature (SAT) anomalies over Europe and North America, relatively little attention has been given to understanding the potential impacts of stratospheric polar vortex over Arctic (SPV) on SAT over Asia. In this study, we found a robust and out‐of‐phase linkage between the SPV in December‐January and SAT in February over Asia during 1979–2022. A stronger SPV tends to induce an anomalous cyclonic circulation characterized by negative geopotential height, facilitating the transport of colder air from higher latitudes to Asia, thereby contributing a cooling effect on the surface. Our findings suggest that the December‐January SPV can serve as a predictor for SAT in February over Asia. Key Points: A strong (weak) SPV in December‐January tends to result in a cooling (warming) over Asia in February on interannual timescalesThe out‐of‐phase linkage between December‐January SPV and February surface air temperature (SAT) is independent of AO in FebruaryThe influence of SPV on Asia SAT is related to the tropospheric circulation anomalies via dynamic process, rather than radiative process [ABSTRACT FROM AUTHOR]

To explore the regulatory mechanism of endogenous hormones in the synthesis of anthocyanins in Anoectochilus roxburghii (Wall.) Lindl (A. roxburghii) under different light intensities, this study used metabolomics and transcriptomics techniques to identify the key genes and transcription factors involved in anthocyanin biosynthesis. We also analyzed the changes in and correlations between plant endogenous hormones and anthocyanin metabolites under different light intensities. The results indicate that light intensity significantly affects the levels of anthocyanin glycosides and endogenous hormones in leaves. A total of 38 anthocyanin-related differential metabolites were identified. Under 75% light transmittance (T3 treatment), the leaves exhibited the highest anthocyanin content and differentially expressed genes such as chalcone synthase (CHS), flavonol synthase (FLS), and flavonoid 3′-monooxygenase (F3′H) exhibited the highest expression levels. Additionally, 13 transcription factors were found to have regulatory relationships with 7 enzyme genes, with 11 possessing cis-elements responsive to plant hormones. The expression of six genes and two transcription factors was validated using qRT-PCR, with the results agreeing with those obtained using RNA sequencing. This study revealed that by modulating endogenous hormones and transcription factors, light intensity plays a pivotal role in regulating anthocyanin glycoside synthesis in A. roxburghii leaves. These findings provide insights into the molecular mechanisms underlying light-induced changes in leaf coloration and contribute to our knowledge of plant secondary metabolite regulation caused by environmental factors. [ABSTRACT FROM AUTHOR]

BACKGROUND: The objective of this investigation was to examine the impact of enzymatic hydrolysis of arabinoxylan (AX) on frozen dough quality under subfreezing conditions. The dough was subjected to freezing at −40 °C for 2 h and then stored at −9, −12, and −18 °C for 15 days. The water loss, freezable water content, water migration, and microstructure of the dough were measured. RESULTS: The dough containing 0.8% cellulase enzymatically hydrolyzed AX (CAX) required the shortest duration when traversing the maximum ice‐crystal formation zone (6.5 min). The dough with xylanase enzymatically hydrolyzed AX (XAX) demonstrated a faster freezing rate than the dough with CAX. The inclusion of both XAX and CAX in the dough resulted in the lowest freezable water loss and reduced freezable water content and free‐water content levels, whereas the inclusion of xylanase‐cellulase combined with enzymatically hydrolyzed AX resulted in higher free‐water content levels. The textural properties of the subfreezing temperature dough were not significantly different from the dough stored at −18 °C and sometimes even approached or surpassed the quality observed in the control group rather than the dough stored at −18 °C. In addition, the gluten network structure remains well preserved in XAX‐ and CAX‐containing doughs with minimal starch damage. CONCLUSION: The enzymatic hydrolysis of AX from wheat bran can be used as a useful additive to improve the quality of frozen dough. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]