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Based on Bass' leadership theory and Bandura's social cognitive theory, we tested the direct relationship between head teacher transformational leadership behavior, head teacher transactional leadership behavior, and junior high school students' school adjustment as well as explored the role of class collective efficacy in mediating this relationship. Surveying 5,083 junior high school students in 168 classes and controlling for grade, head teacher gender, and class size, the hypothesized relationships were tested through a 2-2-1 mediation model using multilevel structural equation modeling. The results indicated that there was not only a direct relationship between head teacher transformational leadership behavior and school adjustment (b = 0.326, 95% confidence interval [CI] [0.218, 0.434]), but also an indirect relationship through class collective efficacy (0.047, 95% CI [0.007, 0.087]), although the direct link was stronger. Moreover, there was only an indirect relationship between head teacher transactional leadership behavior and school adjustment through class collective efficacy (0.051, 95% CI [0.007, 0.096]), and the link between head teacher transformational leadership behavior and school adjustment was stronger than the link between head teacher transactional leadership behavior and school adjustment (diff = 0.351, 95% CI [0.126, 0.577]). This study extended Bass' leadership theory to a class organization, and the relationship between head teacher leadership behavior and school adjustment was explored at the class level in a junior high school.

Abstract Water electro-oxidation to form H2O2 is an important way to produce H2O2 which is widely applied in industry. However, its mechanism is under debate and HO(ads), hydroxyl group adsorbed onto the surface of the electrode, is regarded as an important intermediate. Herein, we study the mechanism of water oxidation to H2O2 at Pt electrode using in-situ Raman spectroscopy and differential electrochemical mass spectroscopy and find peroxide bond mainly originated from the coupling of two CO3 2- via a C2O6 2- intermediate. By quantifying the 18O isotope in the product, we find that 93% of H2O2 was formed via the CO3 2- coupling route and 7% of H2O2 is from OH(ads)-CO3 •− route. The OH(ads)-OH(ads) coupling route has a negligible contribution. The comparison of various electrodes shows that the strong adsorption of CO3(ads) at the electrode surface is essential. Combining with a commercial cathode catalyst to produce H2O2 during oxygen reduction, we assemble a flow cell in which the cathode and anode simultaneously produce H2O2. It shows a Faradaic efficiency of 150% of H2O2 at 1 A cm−2 with a cell voltage of 2.3 V.

In an effort to forge a new pathway for the resourceful utilization of municipal solid waste (MSW) incineration ash, thereby transforming waste into treasure and detriment into benefit, this study investigates the impact of incineration ash on the fundamental properties of expanded clay aggregate aerated concrete blocks. Granular ash and powdered ash were separated from MSW incineration ash. These were then used as replacements for pottery sand and fly ash, respectively, in the production of ceramsite aerated concrete blocks. Replacement ratios were set at 0 %, 10 %, 20 %, 30 %, 40 %, and 50 % of the dry mass proportion. An experimental study was conducted on the product performance indicators of grade CA50.B07 ceramsite aerated concrete blocks at 28 days, including dry density, compressive strength, and thermal conductivity. Furthermore, X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were employed to analyze the micro-material composition and pore structure. The results show that when the replacement rate of granular ash to sand is 20 %, and the replacement rate of powdered ash to fly ash is 10 %, the produced aerated concrete blocks exhibit optimal technical performance while meeting product quality standards. This successfully demonstrates the resource utilization potential of municipal solid waste incineration residues.

Abstract In this bibliometric study, we used the Scopus database to analyse 2188 articles on leadership development in higher education published between 2013 and 2023. We examined publication output and research interest, preferred journals, leading countries, regions, authors, articles and institutions, subject areas and author keywords. Visualisation tools such as VOSviewer were used to gain a comprehensive understanding of patterns and trends in the literature. Recent studies have underscored the importance of leadership development in higher education, particularly in the context of evolving global educational standards (Day et al., (Day et al. in Leadersh Q 25:63–82, 2014); Žalėnienė & Pereira, (Žalėnienė and Pereira in Geography Sustain 2:99–106, 2021)). The results show a fluctuating increase in literature production since 2013, with a significant increase in production after 2020. This surge is attributed to the recognition that leadership is a key competency in shaping the future, especially in the face of the complexity and uncertainty caused by the Covid-19 pandemic. The study also shows that the United States is the most productive country, accounting for more than 50 percent of the total output of the 15 most productive countries. Notably, nine of the 15 most productive universities in these major countries are located in the United States. This highlights the important role that the United States plays in leading the global focus on leadership development in higher education. This study has important implications not only for academics, but also for policy makers, educators and leaders. Through a comprehensive bibliometric analysis, our aim is to contribute to the scholarly discourse on leadership development and higher education, and to encourage deeper discussion and continued innovation in these areas. Examining the development of leadership in higher education over the past decade provides valuable insights that inform research across various social domains. It contributes to a deeper understanding of the development of the field of leadership research in higher education over the past decade, highlighting key aspects of the field, contributors, research priorities and emerging trends. Our study contributes to the achievement of Sustainable Development Goals (SDGs) by enhancing understanding of leadership development in higher education (SDG 4: Quality Education) and fostering international collaboration (SDG 17: Partnerships for the Goals) (in Transforming our world: the 2030 agenda for sustainable development, United Nations General Assembly, New York, 2015).

In order to improve bias flow， jump bar and water plugging phenomenon during ultra-low carbon steel continuous casting process in a factory， through the tunish breathable on the nozzle， plug rod and immersion nozzle such as continuous casting function resistant material improvement， switch the air top nozzle to switch to special diffusion breathable material， blowing into the argon bubbles along the nozzle form uniform air curtain. The surface stomatal rate is 5.2% higher than that before the improvement， which prevents the accumulation of inclusions in the inner wall of the nozzle and alleviates the clogging of the nozzle. One argon hole located in center is changed to six holes of stopper rod， which can realize 360° even argon blowing around its head and decrease inclusion collection on the head. The SEN adopts merterials of carbon free， low aluminum， high silicon content. These refractory can react with the inclusion on the wall of SEN， which prevents its clogging. After the application of improved resistant materials in ultra-low carbon steel， the number of jumping rods per casting is reduced by 0.83 times and 31.8%， the frequency of online replacement of SEN caused by nozzle plugging is reduced by 0.38 pieces and 41.3%， and the control accuracy of crystallization level is stabilized， the qualified rate of cold rolled coil inclusion is improved by 0.238%， and the number of single tunish casting heats is increased by 0.53 heats and increasing by 8%， thus optimizing the flow field of 1 000-2 200 mm. It is proved to put forward to optimize 1 000 mm-2 200 mm caster’s mould flow field.

Summary: Current solid- and liquid-state electrode materials with extreme physical states show inherent limitation in achieving the ultra-stable batteries. Herein, we present a colloidal electrode design with an intermediate physical state to integrate the advantages of both solid- and liquid-state materials. The colloidal electrode was designed based on the inherent water competition effect of (SO4)2− from the aqueous electrolyte and inherently water-soluble polyethylene glycol (PEG)/ZnI2 from the cathode. The constructed aqueous Zn||PEG/ZnI2 colloid battery demonstrated ultra-stable cycling performance with Coulombic efficiencies approaching 100% and a capacity retention of 86.7% over 10,700 cycles, without requiring anodic modification. In addition, the battery also exhibits compatibility with multiple operating conditions including fluctuating charging, limited self-discharging rate, different charging statuses, and fast charging. Moreover, the battery also shows practical potential by integrating with a photovoltaic solar panel charging. This design provides a broad platform for building the next-generation aqueous batteries with ultra-long lifetime.

T-2 toxin, a trichothecene mycotoxin, is an important environmental pollutant that poses a threat globally to the health of humans and animals. It has been found to induce nephrotoxicity; however, the precise molecular mechanism involved remains unclear. In this study, mice were administered at a single dose of 2 mg/kg body weight T-2 toxin intraperitoneally, and kidney function and ultrastructural observations were assessed after 1 d, 3 d, and 7 d. Histopathological findings revealed that exposure to T-2 toxin caused noticeable tubular degeneration, necrosis and epithelial cell shedding in mouse kidneys. Transmission electron microscopy indicated that exposure to T-2 toxin caused mitochondrial swelling and vacuolization. Transcriptomic data revealed significant differences in the expression of 1122, 58, and 391 genes in kidney tissues 1 d, 3 d, or 7 d after T-2 toxin exposure, respectively. Moreover, after 1 d, the downregulated differentially expressed genes (DEGs) were found to be involved in the cell cycle, p53 signaling, and cellular senescence pathways, while the upregulated DEGs were found to be associated with the ribosomal pathway. Temporal changes in gene expression patterns (i.e., after 3 d and 7 d) and disturbances in cellular metabolism during the recovery period (7 d) were detected in mouse kidneys after exposure to T-2 toxin. In conclusion, this study is the first to provide a comprehensive comparative transcriptomic analysis of T-2 toxin exposure-induced nephrotoxicity-related gene regulation at different time points and to investigate the mechanism underlying the nephrotoxicity of T-2 toxin at the mRNA expression level.

Abstract Zinc-ion hybrid supercapacitors (ZHSCs) are attracting significant attention due to their high energies/power densities, safety, and low cost. In this review, recent advances in the development of ZHSCs are summarized. Particular emphasis is placed on state-of-the-art cathodes (including carbon, metal oxides, MXenes, and redox-active polymers), anodes (including Zn-based composites and Zn-free materials) and electrolytes for ZHSCs. Furthermore, the latest research on functional ZHSC devices with miniaturized ZHSCs, fiber-shaped ZHSCs, self-chargeable ZHSCs and self-healing devices is reported. Finally, further developments with ZHSCs are envisaged for future research in this thriving field.

IntroductionThe relationships among microelements and soil microbial communities are essential for understanding the maintenance of soil's ecological functions and their effects on fruit quality in orchards. However, these relationships have not been adequately studied, despite the importance of microelements for the growth of microorganisms and plants.MethodsTo address this research gap, we investigated the relationships among microelements (K, Ca, Na, Mg, Fe, Mn, Zn, and Cu), the diversity and composition of soil microbiomes, and fruit quality in loquat orchards.ResultsWe found that microelements explained more variations in microbial community structures than geographic position, basic soil properties, and macroelements, with 19.6–42.6% of bacterial, 4.3–27.7% of fungal, and 5.9–18.8% of protistan genera significantly correlated with microelements. Among the microelements, AMg and ACu were the most influential in determining the soil microbiome. The soil microbes exhibited varied threshold values for environmental breadth among the microelements, with the broadest range for AMg and the narrowest for AZn. Additionally, the microbes showed significant phylogenetic signals for all microelements, with an increasing divergence of soil microelements. The dominant community assembly shifted from homogeneous selection to stochastic, and then to heterogeneous selection. Moreover, microelements and the microbiome were the top two factors individually explaining 11.0 and 11.4% of fruit quality variation, respectively.DiscussionThese results highlight the importance of microelement fertilization in orchard management and provide scientific guidance for improving fruit quality.

Abstract Ammonium ion batteries are promising for energy storage with the merits of low cost, inherent security, environmental friendliness, and excellent electrochemical properties. Unfortunately, the lack of anode materials restricts their development. Herein, we utilized density functional theory calculations to explore the V2CT x MXene as a promising anode with a low working potential. V2CT x MXene demonstrates pseudocapacitive behavior for ammonium ion storage, delivering a high specific capacity of 115.9 mAh g−1 at 1 A g−1 and excellent capacity retention of 100% after 5000 cycles at 5 A g−1. In-situ electrochemical quartz crystal microbalance measurement verifies a two-step electrochemical process of this unique pseudocapacitive storage behavior in the ammonium acetate electrolyte. Theoretical simulation reveals reversible electron transfer reactions with [NH4 +(HAc)3]···O coordination bonds, resulting in a superior ammonium ion storage capacity. The generality of this acetate ion enhancement effect is also confirmed in the MoS2-based ammonium-ion battery system. These findings open a new door to realizing high capacity on ammonium ion storage through acetate ion enhancement, breaking the capacity limitations of both Faradaic and non-Faradaic energy storage.

This study examined the survival rates of Anadara broughtonii and Chlamys farreri with varying heights throughout winter and summer aquaculture periods under varying ratios of mixed-culture conditions in marine environments. The aim was to assess the viability and economic advantages of mixed-culture practices among different bivalve species. Results indicate that the winter (from December to February of the following year) mortality rate for A. broughtonii in mixed culture ranges from 12.04% to 16.85%, markedly lower than in single-species cultures. Mixed-culture A. broughtonii measuring 2.5–4.0 cm exhibit a significantly reduced summer (from July to September) mortality rate compared to those in single-species cultures (p < 0.05). No significant mortality difference was observed between the monoculture and polyculture of C. farreri. Growth rates of C. farreri and A. broughtonii showed no significant differences between monoculture and polyculture conditions. The optimal size for combining two different species of bivalves is 2.5 cm, with a 1:1 ratio being the most effective. An equal number of seedlings were cultivated across various seawater aquaculture systems for a period of one year. The survival rates of monoculture seedlings of Anadara broughtonii and Chlamys farreri were 60.34% and 86.55%, respectively. In contrast, polyculture seedlings exhibited higher survival rates after one year of mariculture, with Anadara broughtonii at 73.36% and Chlamys farreri at 89.74%. The polyculture of A. broughtonii and C. farreri in suspension cages demonstrates a favorable input–output ratio of 1:2.02. This approach effectively reduces winter and summer mortality rates of A. broughtonii, representing an efficient new method for marine bivalve aquaculture.

Quantifying and interpreting the water–energy–food (WEF) nexus is critical to achieve the sustainable development of urban resources. The mismatch between urban water, energy and food allocations is a prominent problem that is particularly acute in the Yellow River Basin (YRB) of China. In this study, models for the WEF coupling degree and coupling efficiency were constructed. The WEF coupling efficiencies of the 94 cities in the YRB from 2011 to 2020 were quantified using a data envelopment analysis (DEA) model. On this basis, the spatial distribution characteristics and evolutionary trends of different urban WEF coupling efficiencies were analysed and explored using an exploratory spatial data analysis (ESDA) model and a parametric kernel density estimation model. The results show that the energy subsystem constrain the development of the WEF nexus, and the food subsystem, in turn, regulates the development of the WEF nexus. In some years, the phenomenon of ‘resource curse’ occurred, in which the WEF coupling degree increased while the coupling efficiency decreased. Overall, the values of the urban WEF coupling efficiency were low, ranging from 0.5300 to 0.6300, which is not effective. Spatial clustering was detected in the urban WEF coupling efficiency. The clustering types were ‘high–high’ clustering areas in less developed regions and ‘low–low’ clustering areas in developed regions. The two clusters and the median contiguous group had different evolutionary trends. Both efficiency and polarisation increased in the high-clustering group, efficiency improved in the low-clustering group, and a new efficiency pole was formed in the median contiguous group. Among the three grouped cities, we discuss the potential of policies such as cross-city cooperation, intra-city multi-sectoral cooperation and cultivating new central growth cities to improve the WEF coupling efficiency in the YRB.

In order to fully exploit the relationship between temporal features in photovoltaic power generation data and improve the prediction accuracy of photovoltaic power generation, a photovoltaic power generation forecasting method is proposed based on a hybrid model of the convolutional neural network (CNN) and extreme gradient boost (XGBoost). Taking the historical data of China’s photovoltaic power plants as a sample, the high-dimensional mapping relationship of photovoltaic power generation variables is extracted based on the convolutional layer and pooling layer of the CNN network to construct a high-dimensional time-series feature vector, which is an input for the XGBoost. A photovoltaic power generation prediction model is established based on CNN-XGBoost by training CNN and XGBoost parameters. Since it is difficult for a single model to achieve optimal prediction accuracy under different weather conditions, the k-means clustering algorithm is used to group the power datasets and train independent models to improve prediction accuracy. Through the actual data verification of photovoltaic power plants, the proposed photovoltaic power generation prediction model can accurately predict the power, which shows high prediction accuracy and generalization ability compared with other methods.

Abstract The use of lithium–sulfur batteries under high sulfur loading and low electrolyte concentrations is severely restricted by the detrimental shuttling behavior of polysulfides and the sluggish kinetics in redox processes. Two‐dimensional (2D) few layered black phosphorus with fully exposed atoms and high sulfur affinity can be potential lithium–sulfur battery electrocatalysts, which, however, have limitations of restricted catalytic activity and poor electrochemical/chemical stability. To resolve these issues, we developed a multifunctional metal‐free catalyst by covalently bonding few layered black phosphorus nanosheets with nitrogen‐doped carbon‐coated multiwalled carbon nanotubes (denoted c‐FBP‐NC). The experimental characterizations and theoretical calculations show that the formed polarized P–N covalent bonds in c‐FBP‐NC can efficiently regulate electron transfer from NC to FBP and significantly promote the capture and catalysis of lithium polysulfides, thus alleviating the shuttle effect. Meanwhile, the robust 1D‐2D interwoven structure with large surface area and high porosity allows strong physical confinement and fast mass transfer. Impressively, with c‐FBP‐NC as the sulfur host, the battery shows a high areal capacity of 7.69 mAh cm−2 under high sulfur loading of 8.74 mg cm−2 and a low electrolyte/sulfur ratio of 5.7 μL mg−1. Moreover, the assembled pouch cell with sulfur loading of 4 mg cm−2 and an electrolyte/sulfur ratio of 3.5 μL mg−1 shows good rate capability and outstanding cyclability. This work proposes an interfacial and electronic structure engineering strategy for fast and durable sulfur electrochemistry, demonstrating great potential in lithium–sulfur batteries.

Abstract The surface color of cigar tobacco leaves (CTLs) is largely determined by the browning response and is one of the most important quality traits affecting consumer preferences. The physiological changes and metabolic network of browning in CTLs after harvest have not been reported. We investigated the molecular mechanism of browning in CTLs by comparing the physiological characteristics and metabolites of CTLs browning at five postharvest periods. Phenotypic traits and browning-related enzyme activity data indicated that the browning reaction was most intense at approximately 12 d when polyphenol oxidase and peroxidase activities reached their maximum. Postharvest CTLs polyphenols, polyacids, and carbon and nitrogen compounds were rapidly degraded during the yellowing phase, and the biosynthesis rate of polyphenols and carotenoids was greater than the degradation rate during the browning phase. Metabolomic analysis discovered 2027 metabolites that were annotated mainly to lipids and lipid-like molecules, organic acids and their derivatives, and organic heterocyclic components. Hierarchical cluster analysis discovered glutamate, serine, threonine, ornithine, and arginine as the major amino acids involved in the browning reaction. KEGG pathway enrichment analysis indicated that the metabolic pathways with important effects on enzymatic browning were phenylpropanoid biosynthesis, flavonoid biosynthesis, isoquinoline alkaloid biosynthesis, phenylalanine metabolism, and linoleic acid metabolism. The metabolic pathway network was mined, and the main polyphenols involved in the browning reaction of CTLs were found to be cyanidin, rutin, caffeoylquinic acid, kaempferol, naringin, and neohesperidin. This study provides a reference for the browning physiology and metabolism network of postharvest CTLs. Graphical Abstract

Abstract Leaf stacking fermentation involves enzymatic actions of many microorganisms and is an efficient and environmentally benign process for degrading macromolecular organic compounds. We investigated the dynamics of metabolite profiles, bacterial and fungal communities and their interactions during fermentation using cigar leaves from three geographic regions. The results showed that the contents of total sugar, reducing sugar, starch, cellulose, lignin, pectin, polyphenol and protein in cigar tobacco leaves was significantly decreased during fermentation. Notably, the furfural, neophytadiene, pyridine, benzyl alcohol, geranylacetone, 3-hydroxy-2-butanone, N-hexanal, 3-Methyl-1-butanol and 2,3-pentanedione were important features volatile aroma compounds during fermentation. The α-diversity of fungi and bacteria initially increased and then decreased during fermentation. An analysis of variance showed that microbial diversity was influenced by fermentation stages and growing locations, in which the all stages had greater impacts on α- and β-diversity than all regions. Microbiome profiling had identified several core bacteria including Sphingomonas, Bacillus, Staphylococcus, Pseudomonas, Ralstonia, Massilia and Fibrobacter. Fungal biomarkers included Aspergillus, Penicillium, Fusarium, Cladosporium and Trichomonascus. Interestingly, the molecular ecological networks showed that the core taxa had significant correlations with metabolic enzymes and physicochemical properties; bacteria and fungi jointly participated in the carbohydrate and nitrogen compound degrading and volatile aroma compound chemosynthesis processes during fermentation. These studies provide insights into the coupling of material conversion and microbial community succession during leaf fermentation. Graphical abstract

The post-construction improvement technology of bored pile tips has been widely used in the construction of gravel pebble layers, but the diffusion law of the grouting slurry remains to be revealed. To study the diffusion law of the grouting slurry at the tip of bored piles in gravel pebble layers, an equivalent relationship between the seepage continuity equation and the mass diffusion continuity equation was established based on an in-depth comparative analysis; further relying on the Diluted Species Transport Module in Porous Media of Comsol Multiphysics, a three-dimensional numerical model of slurry diffusion was established to systematically study the impact of key factors such as different porosities, grouting times, grouting pressures, slurry diffusion coefficients, and the ratio of vertical to horizontal slurry diffusion coefficients on the diffusion radius of the slurry. The calculation results show that with the continuation of grouting, the increase in porosity, grouting pressure, and slurry diffusion coefficient, or the decrease in the ratio of vertical to horizontal slurry diffusion coefficients, the diffusion range of the slurry increases accordingly. Furthermore, comparatively speaking, the impact of porosity is the smallest, while the impact of the slurry diffusion coefficient is the greatest. The research findings reflect the diffusion trend of the slurry in the gravel pebble layer, which has guiding significance for the quality control of the actual design and construction of grouting.

Based on the combination of core observation, experimental analysis and testingand geological analysis, the main controlling factors of shale oil enrichment in the Lower Permian Fengcheng Formation in the Mahu Sag of the Junggar Basin are clarified, and a shale oil enrichment model is established. The results show that the enrichment of shale oil in the Fengcheng Formation in the Mahu Sag is controlled by the organic abundance, organic type, reservoir capacity and the amount of migration hydrocarbon in shale. The abundance of organic matter provides the material basis for shale oil enrichment, and the shales containing types I and II organic matters have good oil content. The reservoir capacity controls shale oil enrichment. Macropores are the main space for shale oil enrichment in the Fengcheng Formation, and pore size and fracture scale directly control the degree of shale oil enrichment. The migration of hydrocarbons in shale affects shale oil enrichment. The shale that has expelled hydrocarbons has poor oil content, while the shale that has received hydrocarbons migrated from other strata has good oil content. Lithofacies reflect the hydrocarbon generation and storage capacity comprehensively. The laminated felsic shale, laminated lime-dolomitic shale and thick-layered felsic shale have good oil content, and they are favorable lithofacies for shale oil enrichment. Under the control of these factors, relative migration of hydrocarbons occurred within the Fengcheng shale, which leads to the the difference in the enrichment process of shale oil. Accordingly, the enrichment mode of shale oil in Fengcheng Formation is established as “in-situ enrichment” and “migration enrichment”. By superimposing favorable lithofacies and main controlling factors of enrichment, the sweet spot of shale oil in the Fengcheng Formation can be selected which has great significance for the exploration and development of shale oil.

Ship propellers suffered from serious coupling damage of cavitation-erosion (CE) and corrosion when operated with high-speed in the marine environment. To improve the CE-corrosion resistance of the Ni–Al bronze (NAB) propeller alloy, a novel Cu-based medium-entropy alloy coating (Cu55Al20Ni12Ti8Si5, at.%) was prepared by high-velocity oxygen-fuel spraying technology in this study. The characteristics and CE behavior of coating and NAB were comparatively investigated, then the CE damage mechanism was discussed by analyzing CE damage morphologies. The influence of CE on corrosion behavior and the coupling effect between CE and corrosion were further elucidated by electrochemical corrosion experiments. The results indicated that the as-sprayed coating mainly comprised of BCC solid solution phase and NiTi-rich precipitates, which possessed higher hardness (6.73 ± 1.23 GPa) and superior resilience (27.0%) than the NAB. The cumulative mass loss rate for the coating after 18 h CE in distilled water and 3.5 wt.% NaCl solution was only 38.7% and 80.6% that for the NAB, revealing the better anti-CE performance of the coating. The preferential CE of the BCC matrix around the NiTi-rich precipitates, fatigue fracture and lamellar spalling were summarized as the main CE damage mechanism for the coating in 3.5 wt.% NaCl solution. CE had a significant influence on corrosion behavior of coating and NAB, which resulted in corrosion performance degradation of both two materials. The CE-corrosion coupling effect led to the remarkable mass loss, and mechanical effect rather than corrosion effect was ascribed to be the dominated factor for the damage of coating and NAB.

Abstract Background The quality of cigar tobacco leaves was closely related to fermentation. To investigate the substance changes in cigar tobacco leaves during their fermentation, metabolomics was determined at different fermentation stages. In this study, the metabolic profile among different regions and fermentation periods of cigar tobacco leaf were evaluated. Results A total of 1103 metabolites were identified in cigar tobacco leaf samples. A total of 293, 105 and 199 metabolites showed differential accumulation in the cigar tobacco leaf among different regions (PEF0 vs. LCF0, PEF0 vs. DHF0, PEF0 vs. YXF0) and 216, 242, 220, 227 and 198 metabolites showed differential accumulation in the different fermentation (LCF0 vs. LCF1, LCF0 vs. LCF2, LCF0 vs. LCF3, LCF0 vs. LCF4, LCF0 vs. LCF5). The main upregulated compounds were flavonoids, phenolic acids and lignans and coumarins, and the main downregulated compounds were organic acids, phenolic acids and amino acids and derivatives in the fermentation comparison group. Conclusions These results provide valuable information for accurately grasping the end time of fermentation and improve efficiency of cigar tobacco leaf fermentation. Graphical Abstract

AimsCitruses often occur with imbalance in iron nutrition in coastal saline-alkali lands, which severely limits the yield and quality of the fruit. In the rhizosphere, the salt content plays a crucial role in reducing uptake of iron, as well as the activity and abundance of bacteria. However, few studies have explored how salt content affects the effectiveness of iron and the community structure of bacteria across different vertical spatial scales.MethodsWe investigated the citrus rhizosphere (0–30 cm) and bulk (0–60 cm) soil microenvironments of the coastal saline soil were analyzed using the 16S rRNA amplicon and inductively coupled plasma-optical emission spectroscopy.ResultsWe found that the nutrient-related elements in the rhizosphere and bulk soil decreased with increasing soil depth, while the salinity-related elements showed the opposite trend. The nutrient-related element content in the rhizosphere was higher than that in the bulk, whereas the salinity-alkaline-related element content was lower than that in the bulk. The structure and diversity of bacterial communities are affected by the rhizosphere and soil depth. In the bulk, there are enriched bacteria such as WB1-A12, Nitrospiraceae and Anaerolineae that are tolerant to salt-alkali stress. In the rhizosphere, bacteria that promote plant nutrient absorption and secretion of iron carriers, such as Pseudomonas, Streptomyces, and Duganella, are prominent.ConclusionsThe soil depth and rhizosphere affect soil nutrients and saline alkali-related factors. Changes in soil depth and rhizosphere determine the structure and diversity of bacterial communities. Rhizosphere enhances iron absorption promoting bacteria to alleviate iron deficiency stress in saline-alkali soils. Our results indicate that citrus roots maybe can resist the stress of iron deficiency in saline-alkali soils by enhancing iron absorption promoting bacteria.

Layered Ni-rich oxide cathodes in lithium-ion batteries (LIBs) often struggle with poor thermal safety and capacity fade. Xin and colleagues’ studies in Nature and Nature Energy demonstrate a novel high-entropy (compositionally complex) doping strategy, introducing “cocktail effects” from multiple constituents. This approach substantially improves cycling performance and stability, reduces material cost, and may pave the way toward the development of advanced electrodes for next-generation LIBs.

To characterize volatile organic compounds (VOCs) and aromatic sensory properties in Yun cigar, 27 samples from four origins were analyzed using SPME–HS–GC/MS and sensory analysis. The investigation results were analyzed using principal component analysis (PCA), Fisher linear discriminant analysis (LDA), and Pearson correlation analysis. In Yunnan cigars, the content of nicotine and neophytadiene accounted for over 90% of the total VOC content. Nicotine was significantly positively correlated with neophytadiene and phytol. The cigars from four origins were clearly classified by the PCA of VOCs. Four region discrimination functions were established through the LDA of 14 compounds, and the validation accuracy was 100%. The sensory descriptors with the highest geometric mean were woody, roasted, fresh-sweet, bean, and scorched. Acetophenone, megastigmatrienone A, and thunbergene were positively correlated with multiple aroma descriptors, while nicotine was negatively correlated with multiple aroma descriptors.

For the three-dimensional conductive host, the uneven lithium deposition and the dependence on the pore structure and lithiophility are a great challenge for lithium metal anodes. Herein, we employed facial chemical etching techniques on brass foil to fabricate three-dimensional copper hosts with diverse pore structures and lithiophilities, thus intending to understand the lithium depositing mechanisms in porous hosts. The copper host with a more pronounced pore structure exhibits the lower polarization voltage induced by its large specific surface area, which reduces the local current density and provides a great deal of pathway for lithium ion diffusion. Meanwhile, it exhibits high nucleation overpotential and a short lifespan due to a reduced number of favorable lithium nucleation sites caused by the reduced lithiophilic zinc sites and a marked increase in the routes between nucleation sites. Therefore, the appropriate pore structure needs a consideration of efficient balance between the nucleation overpotential, the polarization voltage, and Coulombic efficiency. This insight underscores the pivotal role of well-suited pore structures in three-dimensional hosts, providing profound guidance for the efficient design of advanced host for lithium metal anode.

Abstract This study examines the influence of social support on bystander behaviors, the mediating and moderating effects of moral disengagement and defender self-efficacy at the individual and class levels, and their cross-level interaction. A total of 1310 children in grades 4–6 completed our questionnaire survey at four-time points between October and December in 2021. The questionnaires include the Scale of Perceived Social Support (T1), Moral Disengagement Scale (T2), Defender Self-Efficacy Scale (T3), and Bullying Participant Behaviors Questionnaire (T4). The multilevel moderated mediating model results show that (1) social support negatively predicts reinforcer and outsider behavior and positively predicts defender behavior; (2) defender self-efficacy plays a mediating role between social support and defender behavior, moral disengagement plays a mediating role between social support and bystander behaviors, and defender self-efficacy and moral disengagement play a chain mediation role between social support and bystander behavior; (3a) class-level defender self-efficacy has a direct impact on defender behavior and moderates the relationship between individual defender self-efficacy and reinforcer behavior; and (3b) class-level moral disengagement has a direct impact on defender and outsider behavior and a cross-level moderated role between individual moral disengagement and reinforcer behavior. These results show that the individual and class level defender self-efficacy and moral disengagement can influence the bystander behavior of primary school students, which is of great significance for schools to develop anti-bullying moral education courses and design measures to improve students’ anti-bullying self-efficacy.

Abstract Upgrading of atmospheric CO2 into high‐value‐added acetate using renewable electricity via electrocatalysis solely remains a great challenge. Here, inspired by microbial synthesis via biocatalysts, we present a coupled system to produce acetate from CO2 by bridging inorganic electrocatalysis with microbial synthesis through formate intermediates. A 3D Bi2O3@CF integrated electrode with an ice‐sugar gourd shape was fabricated via a straightforward hydrothermal synthesis strategy, wherein Bi2O3 microspheres were decorated on carbon fibers. This ice‐sugar gourd‐shaped architecture endows electrodes with multiple structural advantages, including synergistic contribution, high mass transport capability, high structural stability, and large surface area. Consequently, the resultant Bi2O3@CF exhibited a maximum Faradic efficiency of 92.4% at −1.23 V versus Ag/AgCl for formate generation in 0.5 M KHCO3, exceeding that of Bi2O3/CF prepared using a conventional electrode preparation strategy. Benefiting from the high formate selectivity, unique architecture, and good biocompatibility, the Bi2O3@CF electrode attached with enriched CO2‐fixing electroautotrophs served as a biocathode. As a result, a considerable acetate yield rate of 0.269 ± 0.009 g L−1 day−1 (a total acetate yield of 3.77 ± 0.12 g L−1 during 14‐day operation) was achieved in the electrochemical–microbial system equipped with Bi2O3@CF.

The cavitation-silt erosion (CSE) has caused severe technical challenges and economic losses to the hydro-turbine operated in silt-laden river. In this manuscript, two hardfacing (i.e., WC-20(Cr3C2)-7Ni and Cr3C2-25(NiCr)) coatings were manufactured via a high-velocity oxygen fuel (HVOF) spraying method, and effects of flow velocities (FVs) and sand concentrations (SCs) on their CSE behaviors with the help of a rotating disk rig facility were investigated. Results indicated that the WC-20(Cr3C2)-7Ni coating exhibited lower porosity, higher KIC, H/E and H3/E2 as well as superior CSE resistance, and its CSE resistance was less affected by FV as well as SC compared with the Cr3C2-25(NiCr) coating. Both FV and SC had a positive effect on the CSE degradation of the two hardfacing coatings, while SC had a greater effect on their CSE resistances than FV. With increasing FV and SC, the WC-20(Cr3C2)-7Ni coating experienced the CSE damage of the few micro-cracks, scattered cavitation pinholes, fracturing of carbide particles, pronounced scour marks, isolation and peeling off of carbide particles, and crater formation, while the CSE process of the Cr3C2-25(NiCr) coating primarily included the micro-cracks and scattered cavitation pinholes, peeling off of chromium carbide particles, long and deep scour marks, and coating spalling and crater formation.

Aqueous rechargeable batteries have drawn wide attention owing to the advantages of low cost, high safety, and rapid kinetic process. In recent years, the use of NH4+ ions and other nonmetallic ions as carrier batteries has come into researchers’ view. The storage of NH4+ shows fast diffusion kinetics and the ability to achieve highly reversible redox processes by forming hydrogen bonds between NH4+ and electrode materials. Designing and exploration of advanced materials for NH4+ storage are of high significance in building high‐performance aqueous battery systems. This review summarizes the latest advances of critical materials, including Prussian blue analogs, transition metal oxides, and organic compounds for NH4+ batteries. Comparison of properties among different materials is discussed in detail. Different NH4+ storage behaviors according to several kinds of materials are demonstrated. Finally, the challenges and valuable perspectives for the further development of aqueous NH4+ batteries are also provided.

IntroductionA series of symptoms, including fever, widespread pain, fatigue, and even ageusia, have frequently been reported in the context of various infections, such as COVID-19. Although the pathogenic mechanisms underlying an infection causing fever and pain have been well established, the mechanisms of fatigue induced by infection in specific brain regions remain unclear.MethodsTo elucidate whether and how the peripheral infection cause fatigue via regional neuroinflammation, we performed a brain-wide investigation of neuroinflammation in a peripheral pseudoinfection rat model using [18F]DPA-714 positron emission tomography (PET) imaging analysis, in which the polyriboinosinic: polyribocytidylic acid (poly I:C) was intraperitoneally injected.ResultsTransient fever lasting for several hours and subsequent suppression of spontaneous activity lasting a few days were induced by poly I:C treatment. Significant increase in plasma interleukin (IL)-1β, IL-6 and tumour necrosis factor (TNF)-α were observed at 2 and 4 h following poly I:C treatment. PET imaging analysis revealed that the brain uptake of [18F]DPA-714 was significantly increased in several brain regions one day after poly I:C treatment, such as the dorsal raphe (DR), parvicellular part of red nucleus (RPC), A5 and A7 noradrenergic nucleus, compared with the control group. The accumulation of [18F]DPA-714 in the DR, RPC and A5 was positively correlated with subsequent fatigue-like behavior, and that in the A7 tended to positively correlate with fever.DiscussionThese findings suggest that peripheral infection may trigger regional neuroinflammation, which may cause specific symptoms such as fatigue. A similar mechanism might be involved in COVID-19.

Source rocks of the Dongying Formation are widely distributed in the Bozhong Sag. It is of great significance to clarify the characteristics and paleoenvironment of the source rocks to promote conventional and unconventional oil and gas exploration in the Bozhong Sag. In this study, organic and inorganic geochemical experiments were carried out on the source rock samples collected from the Dongying Formation in the Bozhong Sag, with aims to analyze the quality and paleoenvironment and compare it with the Shahejie Formation. The results show that: ①the characteristics of source rocks in different layers of the Dongying Formation are significantly different from those in Es1-2.The abundance of organic matter in the lower and third members of the Dongying Formation (Ed2L and Ed3) is high and has reached the mature-high maturity stage. The organic matter of the Dongying Formation is mainly type Ⅱ. ②According to the Pr/nC17-Ph/nC18 charts, the source of organic matter in the Dongying Formation is mixed type, which is obviously different from the low algae of Es1-2.③The paleoenvironment during the formation of source rocks was analyzed by combining the contents or ratios of 16 elements, such as Sr/Cu, Mn/Fe, Pr/Ph and the gammacerane index. Different from the strong reduction-salinized lacustrine basin in the arid climate of Es1-2, the Dongying Formation was formed in a warm and humid climate, accompanied by strong terrigenous input, and controlled in a weakly oxidized freshwater environment. Longitudinally, the paleoclimate changes little from Ed3 to Ed1, and the water salinity is basically the same, but the water depth becomes shallower and the water oxidation conditions show a trend of increasing gradually.④Using Co and La contents to quantitatively restore the paleo-water depth during the deposition of the Dongying Formation, and suggests that Ed3 (50.4 m)>Ed2 (35.7 m)≈Es1-2(33.2 m)≈Ed1(31.7 m). The calculated results are consistent with the previous qualitative results of paleo-water depth.

Pore structure is the key element of tight sandstone reservoirs, which restricts the accumulate and flow of oil and gas in reservoirs. The pore structure is one of the key and difficult point of unconventional oil and gas exploration and development. In this paper, ten dense core samples from the Upper Triassic Yanchang Group 7 section in the Heshui area of the Ordos Basin are selected to carry out experiments, including high-pressure mercury pressure and X-diffraction. Fractal theory is used to analyze the characteristics of pore throats, then the relationship between fractal dimension and reservoir physical properties, pore structure and mineral content is analyzed. The results show that according to the mercury pressure curve and pore structure, the reservoir is divided into categories Ⅰ, Ⅱ and Ⅲ, its reservoir performance and seepage capacity decrease in turn, and the microheterogeneity is enhanced. Different types of reservoirs have different fractal characteristics: according to the inflection points of fractal curves 0.05 and 0.02 μm. The pore size of class Ⅰ reservoirs is divided into large pores (> 50 nm) and medium pores (50-6 nm) by combining the actual situation with the standard of pore size division proposed by IUPAC. According to the inflection point, the reservoirs of classes Ⅱ and Ⅲ can be divided into medium pores a (50-20 nm) and mesoporous B (20-6 nm). The average fractal dimension increased, which was 2.619 3, 2.745 4 and 2.852 6, respectively, and the heterogeneity gradually increased. The main permeability is contributed by fewer large pores, and the fractal dimension mainly reflects the heterogeneity of pore size. The fractal dimension is related to some minerals. Mineral composition and content are the internal factors that determine the fractal dimension and then affect the quality and pore structure of reservoirs.

High-temperature wear behaviors are of prime importance for broadening the application guidelines of the Al-based amorphous coatings. For this objective, the effects of ambient temperatures on tribological behaviors of the AlNiTi amorphous coatings were investigated from room temperature (RT) to 450 °C. The results showed that the wear rate for the coating slid at 300 °C declines by two orders of magnitude in comparison to 2219-Al and 7075-Al alloys due to high hardness, strain tolerance, and elastic recovery capacity. With increasing temperatures, friction coefficients decrease steadily as a result of the oxide tribo-films formed on the wear track. However, there is an initial decrease in wear rate up to the temperature of 400 °C followed by a slight increase after the full devitrified temperature. The coating shows superior wear resistance at an elevated temperature of 400 °C because of the remained amorphous structure and intact protective oxide tribo-film. The wear mechanism of the coating transfers from brittle spalling coupled with oxidation wear to oxidative wear with increasing temperature up to 400 °C. After full devitrified temperature, the formation of deformed layers beneath oxide tribo-film aggravates marginally the wear of the coating. The synergistic effects of structure evolution, high-temperature hardness, and oxidization on tribological behaviors were discussed. These current findings provide insights into the real applications of the AlNiTi amorphous coating at evaluated temperatures.

Improving the hydro-abrasive erosion (HAE) resistance of the existing flow-handling components has been a matter of continuous effort for the hydraulic machineries. In current work, the effects of sand concentrations (SC) and flow velocities (FV) on HAE behaviors of high-velocity oxygen-fuel (HVOF) sprayed carbide-based cermet (i.e. Cr3C2–NiCr and WC–Cr3C2–Ni) coatings were studied using a rotating disk rig facility. The obtained results revealed that the WC–Cr3C2–Ni coating possessed lower porosity value, higher hardness (H) and elastic modulus (E) values, superior HAE resistances, and appeared less influenced by SC as well as FV compared with the Cr3C2–NiCr coating. Higher SC and FV caused more severe HAE degradations for both carbide-based cermet coatings, while FV had a greater influence on HAE resistances for both coatings than SC. With the increase of the SC and FV, the Cr3C2–NiCr coating experienced the HAE process of the isolation of hard phase grains as well as the scouring, the connection of micro-cracks as well as severe plastic deformations, and the crater formation as well as deep scour marks, while the HAE process of the WC–Cr3C2–Ni coating mainly included the micro-cracks, the erosion pits, and the scour marks.

Aqueous rechargeable Zn batteries have been studied as promising energy storage devices because of their low cost, high safety, and environmental friendliness. However, due to the problems faced by Zn anodes, such as dendrites and parasitic reactions (hydrogen evolution reaction and corrosion), commercialization still has a long way to go. In this perspective, a discussion of Zn anodes' current challenges is presented. Starting from this overview Zn anode modification strategies are discussed, which include surface modification, structure optimization, and electrolyte modification. Finally, prospects of future research on Zn anode are outlined.

Changes in volatile metabolites during cigar tobacco leaves fermentation as well as the metabolic pathways of metabolites with significant differences were investigated to determine the influence of cigar tobacco leaves fermentation on its flavor. The volatile substances in cigar tobacco leaves at different stages were detected by headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), and the main differences in volatile substances in cigar tobacco leaves at different fermentation stages of Yunxue1 in Yuxi production area were analyzed by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The results show that in the process of cigar tobacco leaves fermentation (YXF0, YXF1, YXF2, YXF3, YXF4, YXF5), a total of 613 volatile metabolites were detected, and a significant difference was found in 263 kinds of metabolites. Among them, the main upregulated differential metabolites were 1,3,6,10-Cyclotetradecatetraene, 3,7,11-trimethyl-14-(1-methylethyl)-, [S-(E,Z,E,E)]-, Benzoic acid, Benzaldehyde, etc. While the main downregulated differential metabolites included beta.-Myrcene, trans-Farnesol, etc. The metabolites with significant differences are mainly concentrated in the biosynthesis of monoterpenes, diterpenes, sesquiterpenes and triterpenes, the degradation metabolism of amino acids, such as valine, leucine and isoleucine, and the biosynthesis of phenylpropyl. There were 8 different metabolites in 5 groups, including 4- (1-methylethyl) -1-cyclohexene-1-formaldehyde、2, 4-dihydroxyacetophenone、2-methylbutyl 3-methylbutyrate and methylpyrazine, all of which showed upregulation trend during fermentation. In the fermentation process, volatile metabolites participate in various synthesis and degradation pathways. The biosynthesis pathway of terpenes and amino acid synthesis and degradation pathway are connected to produce various terpenes, aldehydes and other substances, such as 1,3,6,10-Cyclotetradecatetraene, 3,7,11-trimethyl-14-(1-methylethyl)-, [S-(E,Z,E,E)]-、benzaldehyde and 4-hydroxybenzaldehyde, which are conducive to the overall flavor and quality of cigar tobacco leaves.

Abstract The market demand for energy pushes researchers to pay a lot of attention to Li‐S batteries. However, the ‘shuttle effect’, the corrosion of lithium anodes, and the formation of lithium dendrites make the poor cycling performances (especially under high current densities and high sulfur loading) of Li‐S batteries, which limit their commercial applications. Here, a separator is prepared and modified with Super P and LTO (abbreviation SPLTOPD) through a simple coating method. The LTO can improve the transport ability of Li+ cations, and the Super P can reduce the charge transfer resistance. The prepared SPLTOPD can effectively barrier the pass‐through of polysulfides, catalyze the reactions of polysulfides into S2−, and increase the ionic conductivity of the Li‐S batteries. The SPLTOPD can also prevent the aggregation of insulating sulfur species on the surface of the cathode. The assembled Li‐S batteries with the SPLTOPD can cycle 870 cycles at 5 C with the capacity attenuation of 0.066% per cycle. When the sulfur loading is up to 7.6 mg cm−2, the specific discharge capacity at 0.2 C can reach 839 mAh g−1, and the surface of lithium anode after 100 cycles does not show the existence lithium dendrites or a corrosion layer. This work provides an effective way for the preparation of commercial separators for Li‐S batteries.

With the rapid development of unconventional oil and gas resources, the demand for corresponding evaluation methods is increasing. At present, the evaluation methods for unconventional oil and gas resources are divided into analogy, statistical and genetic method. While constantly innovating evaluation methods, how to improve conventional methods and apply them to unconventional resource evaluation is also a focus and difficulty in current research. Taking a well as an unit and the EUR of the well as the unit's oil or gas reserves, a Pareto distribution model was established, and a program was compiled according to the principle of random sampling and skew sampling to analyze the sensitivity of number N, shape parameter and exploration coefficient E to the model. This method was applied to the shale oil resource evaluation in the X230 well block in Heshui area of Ordos Basin. Results show that the number of discoveries affects the size and dispersion of the parameters for oilfield distribution. The distribution model tends to be stable when the number is more than 300. Exploration coefficient has little influence on the sensitivity of distribution model, which is the limitation of taking EUR as evaluation unit. According to the variation of number N with shape parameter β, the number corresponding to cut-off point can be determined, that is, the sum of EUR of all wells is the recoverable resource of the area, which is 6.72×106 t. The result is consistent with the evaluation of oil and gas resource abundance. This method can provide guidance for unconventional oil and gas resources evaluation.

Abstract Direct photoelectrochemical 2‐electron water oxidation to renewable H2O2 production on an anode increases the value of solar water splitting. BiVO4 has a theoretical thermodynamic activity trend toward highly selective water oxidation H2O2 formation, but the challenges of competing 4‐electron O2 evolution and H2O2 decomposition reaction need to overcome. The influence of surface microenvironment has never been considered as a possible activity loss factor in the BiVO4‐based system. Herein, it is theoretically and experimentally demonstrated that the situ confined O2, where coating BiVO4 with hydrophobic polymers, can regulate the thermodynamic activity aiming for water oxidation H2O2. Also, the hydrophobicity is responsible for the H2O2 production and decomposition process kinetically. Therefore, after the addition of hydrophobic polytetrafluoroethylene on BiVO4 surface, it achieves an average Faradaic efficiency (FE) of 81.6% in a wide applied bias region (0.6–2.1 V vs RHE) with the best FE of 85%, which is 4‐time higher than BiVO4 photoanode. The accumulated H2O2 concentration can reach 150 µm at 1.23 V versus RHE under AM 1.5 illumination in 2 h. This concept of modifying the catalyst surface microenvironment via stable polymers provides a new approach to tune the multiple‐electrons competitive reactions in aqueous solution.