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The oxygen discharge process significantly affects the electrochemical performance of a proton exchange membrane water electrolyzer (PEMWE), which requires an optimal structure of the flow field implemented in the bipolar plate (BP) component. In this study, we numerically investigated the two-phase (liquid water and oxygen) flow in the PEMWE's channel region with different outlet manifold structures utilizing the volume of fluid (VOF) model. Then, the oxygen volume fraction at the liquid/gas diffusion layer (L/GDL) surface, i.e., the interface of the channel and L/GDL, obtained by the liquid water and oxygen flow model was incorporated into a three-dimensional (3D) PEMWE model, which made it possible to predict the influence of the outlet manifold structure on the multiple transfers inside the whole electrolyzer as well as the electrochemical performance. The results indicate that the existence of oxygen in the flow field significantly decreased the electrolyzer voltage at a fixed operation current density and deteriorated the uniform distribution of the oxygen amount, current density (corresponding to the electrochemical reaction rate) and temperature in the membrane electrode assembly (MEA), indicating that the rapid oxygen removal from the flow field is preferred in the operation of the electrolyzer. Moreover, slight increases in the width of the outlet manifold were helpful in relieving the oxygen accumulation in the anode CL and, hence, improved the electrolyzer performance with more uniform distribution characteristics. [ABSTRACT FROM AUTHOR]

The return of agricultural waste to the field is one of the most effective strategies of increasing crop yield, improving the soil's physicochemical properties, and improving the soil rhizosphere environment. In the present study, sheep manure (SM), cow manure (CM), tail vegetable (TV), mushroom residue (MR), and corn straw (CS) were used as raw materials, and no fertilization (CK1) and local commercial organic fertilizer (CK2) treatments were used as controls. Eight composts were set up using specific mass ratios of different compost materials. After fermentation, field experiments were conducted to determine the cabbage yield, soil's physicochemical properties, and soil rhizosphere conditions. The eight composts increased the soil organic matter and nutrient contents significantly. Among the eight fermentation formulas, T6 (CM:CS:TV:SM = 1:1:2:6), T7 (MR:CS:TV:SM = 1:1:2:6), and T8 (CM:MR:CS:TV:SM = 1:1:1:2:5) were relatively effective. Therefore, high-throughput sequencing was performed on T6, T7, T8, CK1, and CK2. T6, T7, and T8 exhibited increased relative abundance of Proteobacteria, Actinomycetes, and Firmicutes, while the Acidobacteria abundance was decreased. In addition, Ascomycota's and Basidiomycetes' relative abundance decreased, and the oil chytrid and mortierella increased. The microbial community structure was affected significantly by pH, electrical conductivity, available potassium, available nitrogen, and organic matter. In general, the three composts increased yield by improving the soil's physicochemical properties, fertility, and microbial community structure. Among them, T6 had the most significant effect and is the optimal formula for use as a local organic cabbage fertilizer, and it could facilitate sustainable agricultural development. [ABSTRACT FROM AUTHOR]

Microbial deterioration as one of the widespread problems in archaeological site museums significantly affects their safety and exhibits. This paper systemically investigated the environments and conditions of microbial outbreaks in the Dadiwan No. F901 site museum, which is a representative archaeological site of prehistoric Yangshao culture. The morphology and harmful characteristics of the outbreak microorganisms were analyzed by microscopic techniques. The ultraviolet resistance of harmful microorganisms was also studied. Combining these findings with the original facilities of the site museum, a scientific and reasonable project was proposed to control and prevent the activity of harmful microorganisms. In addition, a 1% OIT/DCOIT biocide concentration was applied to inhibit microorganism-caused deterioration, in combination with mechanical removal based on laboratory tests and screening in situ. The effectiveness of microbial control was assessed using a portable microscope, ATP bioluminescence assay, and color difference detection. As a long-lasting preventive measure for microbial deterioration, an ultraviolet sterilization system can efficaciously prevent the re-outbreak of microbial deterioration to form a relatively stable dynamic balance for the surroundings of the site. This study is a resultful exploration in terms of microbial control and plays an important role in the sustainable protection of archaeological site museums. [ABSTRACT FROM AUTHOR]

Drought stress restricts vegetable growth, and abscisic acid plays an important role in its regulation. Sucrose non-fermenting1-related protein kinase 2 (SnRK2) is a key enzyme in regulating ABA signal transduction in plants, and it plays a significant role in response to multiple abiotic stresses. Our previous experiments demonstrated that the SnRK2.11 gene exhibits a significant response to drought stress in cucumbers. To further investigate the function of SnRK2.11 under drought stress, we used VIGS (virus-induced gene silencing) technology to silence this gene and conducted RNA-seq analysis. The SnRK2.11-silencing plants displayed increased sensitivity to drought stress, which led to stunted growth and increased wilting speed. Moreover, various physiological parameters related to photosynthesis, chlorophyll fluorescence, leaf water content, chlorophyll content, and antioxidant enzyme activity were significantly reduced. The intercellular CO2 concentration, non-photochemical burst coefficient, and malondialdehyde and proline content were significantly increased. RNA-seq analysis identified 534 differentially expressed genes (DEGs): 311 were upregulated and 223 were downregulated. GO functional annotation analysis indicated that these DEGs were significantly enriched for molecular functions related to host cells, enzyme activity, and stress responses. KEGG pathway enrichment analysis further revealed that these DEGs were significantly enriched in phytohormone signalling, MAPK signalling, and carotenoid biosynthesis pathways, all of which were associated with abscisic acid. This study used VIGS technology and transcriptome data to investigate the role of CsSnRK2.11 under drought stress, offering valuable insights into the mechanism of the SnRK2 gene in enhancing drought resistance in cucumbers. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is involved in the regulation of plant salt stress as a potential signaling molecule. This work investigated the effect of H2S on cucumber growth, photosynthesis, antioxidation, ion balance, and other salt tolerance pathways. The plant height, stem diameter, leaf area and photosynthesis of cucumber seedlings were significantly inhibited by 50 mmol·L−1 NaCl. Moreover, NaCl treatment induced superoxide anion (O2·−) and Na+ accumulation and affected the absorption of other mineral ions. On the contrary, exogenous spraying of 200 μmol·L−1 sodium hydrosulfide (NaHS) maintained the growth of cucumber seedlings, increased photosynthesis, enhanced the ascorbate–glutathione cycle (AsA–GSH), and promoted the absorption of mineral ions under salt stress. Meanwhile, NaHS upregulated SOS1, SOS2, SOS3, NHX1, and AKT1 genes to maintain Na+/K+ balance and increased the relative expression of MAPK3, MAPK4, MAPK6, and MAPK9 genes to enhance salt tolerance. These positive effects of H2S could be reversed by 150 mmol·L−1 propargylglycine (PAG, a specific inhibitor of H2S biosynthesis). These results indicated that H2S could mitigate salt damage in cucumber, mainly by improving photosynthesis, enhancing the AsA–GSH cycle, reducing the Na+/K+ ratio, and inducing the SOS pathway and MAPK pathway. [ABSTRACT FROM AUTHOR]

Low-light intensity affects plant growth and development and, finally, causes a decrease in yield and quality. There is a need for improved cropping strategies to solve the problem. We previously demonstrated that moderate ammonium:nitrate ratio (NH4+:NO3−) mitigated the adverse effect caused by low-light stress, although the mechanism behind this alleviation is unclear. The hypothesis that the synthesis of nitric oxide (NO) induced by moderate NH4+:NO3− (10:90) involved in regulating photosynthesis and root architecture of Brassica pekinesis subjected to low-light intensity was proposed. To prove the hypothesis, a number of hydroponic experiments were conducted. The results showed that in plants exposed to low-light intensity, the exogenous donors NO (SNP) and NH4+:NO3− (N, 10:90) treatments significantly increased leaf area, growth range, and root fresh weight compared with nitrate treatment. However, the application of hemoglobin (Hb, NO scavenger), N-nitro-l-arginine methyl ester (L-NAME, NOS inhibitor), and sodium azide (NaN3, NR inhibitor) in N solution remarkably decreased the leaf area, canopy spread, the biomass of shoot and root, the surface area, and volume and tips of the root. The application of N solution and exogenous SNP significantly enhanced Pn (Net photosynthetic rate) and rETR (relative electron transport rates) compared with solo nitrate. While all these effects of N and SNP on photosynthesis, such as Pn, Fv/Fm (maximum quantum yield of PSII), Y(II) (actual photosynthetic efficiency), qP (photochemical quenching), and rETR were reversed when the application of Hb, L-NAME, and NaN3 in N solution. The results also showed that the N and SNP treatments were more conducive to maintaining cell morphology, chloroplast structure, and a higher degree of grana stacking of low-light treated plants. Moreover, the application of N significantly increased the NOS and NR activities, and the NO levels in the leaves and roots of mini Chinese cabbage seedlings treated with N were significantly higher than those in nitrate-treated plants. In conclusion, the results of this study showed that NO synthesis induced by the appropriate ammonia–nitrate ratio (NH4+:NO3− = 10:90) was involved in the regulation of photosynthesis and root structure of Brassica pekinesis under low-light stress, effectively alleviating low-light stress and contributing to the growth of mini Chinese cabbage under low-light stress. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (AZIBs) are promising for large-scale energy storage systems due to their high safety, large capacity, cost-effectiveness, and environmental friendliness. However, their commercialization is currently hindered by several challenging issues, including cathode degradation and zinc dendrite growth. Recently, metal-organic frameworks (MOFs) and their derivatives have gained significant attention and are widely used in AZIBs due to their highly porous structures, large specific surface area, and ability to design frameworks for Zn2+ shuttle. Based on preceding contributions, this review aims to generalize two design principles for MOF-based materials in AZIBs: cathode preparation and anode protection. For cathode preparation, we mainly introduce novel MOF-based electrode materials such as pure MOFs, porous carbon materials, metal oxides, and their compounds, focusing on the analysis of the specific capacity of AZIBs. For anode protection, we systematically analyze MOF-based materials used as 3D Zn architecture, solid electrolyte interfaces, novel separators, and solid-state electrolytes, highlighting the improvement in the cyclic stability of Zn anodes. Finally, we propose the future development of MOF-based materials in AZIBs. Our work can give some clues for raising the practical application level of aqueous ZIBs. [ABSTRACT FROM AUTHOR]

Composting, planting, and breeding waste for return to the field is the most crucial soil improvement method under the resource utilization of agricultural waste. However, how the vegetable yield and rhizosphere soil environment respond to different composts is still unknown. Therefore, eight formulations were designed for compost fermentation using agricultural waste [sheep manure (SM), tail vegetable (TV), cow manure (CM), mushroom residue (MR), and corn straw (CS)] without fertilizer (CK1) and local commercial organic fertilizer (CK2) as controls to study the yield and rhizosphere soil environment of greenhouse zucchini in response to different planting and breeding waste compost. Applying planting and breeding waste compost significantly increased the soil's organic matter and nutrient content. It inhibited soil acidification, which T4 (SM:TV:CS = 6:3:1) and T7 (SM:TV:MR:CS = 6:2:1:1) treatments affected significantly. Compared to CK2 treatment, T4 and T7 treatments showed a greater increase, with a significant increase of 14.69% and 11.01%, respectively. Therefore, T4, T7, and two control treatments were selected for high-throughput sequencing based on yield performance. Compared with the CK1 treatment, although multiple applications of chemical fertilizers led to a decrease in bacterial and fungal richness, planting and breeding waste compost maintained bacterial diversity and enhanced fungal diversity. Compared to CK2, the relative abundance increased in T7-treated Proteobacteria (Sphingomonas, Pseudomonas, and Lysobacter) and T4-treated Bacteroidetes (Flavobacterium) among bacteria. An increase in T4-treated Ascomycota (Zopfiella and Fusarium) and Basidiomycota among fungi and a decrease in T7-treated Mortierellomycota have been observed. Functional predictions of the bacterial Tax4Fun and fungal FUNGuild revealed that applying planting and breeding waste compost from the T4 treatment significantly increased the abundance of soil bacterial Metabolism of Cities, Genetic Information Processing, and Cellular Processes decreased the abundance of Pathotroph and Saprotroph-Symbiotroph fungi and increased the abundance of Saprotroph fungi. Overall, planting and breeding waste compost increased zucchini yield by improving soil fertility and microbial community structure. Among them, T4 treatment has the most significant effect, so T4 treatment can be selected as the optimized formulation of local commercial organic fertilizer. These findings have valuable implications for sustainable agricultural development. [ABSTRACT FROM AUTHOR]

Irreversible phase transition caused capacity fading has been considered as an obstacle for rechargeable batteries. An in-depth investigation of the irreversible phase transition is critical for understanding the reaction mechanism and developing advanced batteries. In this work, taking vanadium oxide and its alkali ion-stabilized intercalation compounds (A-V-O, A = Li, Na, K) as prototypes, utilizing operando characterizations, we discovered coupled discontinuous (interlayer)-continuous (intralayer) transitions in the stabilized multielectron intercalation cathodes. The highly ordered crystal of vanadium pentoxide irreversibly transfers to a disordered/amorphous structure after the first cycle, whereas A-V-O enables reversible discontinuous lattice transitions at the interlayer pathway for facilitating lithium diffusion. Among the A-V-O family, K-V-O, with the highest capacity retention, shows a coupled discontinuous-continuous transition, which exhibits a continuous transition and the minimum volume change at the V-O intralayer during lithium intercalation/deintercalation. These coupled discontinuous-continuous lattice transitions were captured for the first time in cathode materials. It implies that the suitable ion intercalation induced continuous intralayer transition inhibits the irreversible ion intercalation and phase transition. [ABSTRACT FROM AUTHOR]

Appropriate nucleo-cytoplasmic partitioning of proteins is a vital regulatory mechanism in phytohormone signaling and plant development. However, how this is achieved remains incompletely understood. The Karyopherin (KAP) superfamily is critical for separating the biological processes in the nucleus from those in the cytoplasm. The KAP superfamily is divided into Importin α (IMPα) and Importin β (IMPβ) families and includes the core components in mediating nucleocytoplasmic transport. Recent reports suggest the KAPs play crucial regulatory roles in Arabidopsis development and stress response by regulating the nucleo-cytoplasmic transport of members in hormone signaling. However, the KAP members and their associated molecular mechanisms are still poorly understood in maize. Therefore, we first identified seven IMPα and twenty-seven IMPβ genes in the maize genome and described their evolution traits and the recognition rules for substrates with nuclear localization signals (NLSs) or nuclear export signals (NESs) in plants. Next, we searched for the protein interaction partners of the ZmKAPs and selected the ones with Arabidopsis orthologs functioning in auxin biosynthesis, transport, and signaling to predict their potential function. Finally, we found that several ZmKAPs share similar expression patterns with their interacting proteins, implying their function in root development. Overall, this article focuses on the Karyopherin superfamily in maize and starts with this entry point by systematically comprehending the KAP-mediated nucleo-cytoplasmic transport process in plants, and then predicts the function of the ZmKAPs during maize development, with a perspective on a closely associated regulatory mechanism between the nucleo-cytoplasmic transport and the phytohormone network. [ABSTRACT FROM AUTHOR]

(1) Background: Cinnamic acid (CA) is a harmful substance secreted by the roots of continuous-cropping crops. (2) Methods: This study aimed to investigate how exogenous Si affects chlorophyll content and carbon metabolism in cucumber seedlings under CA-induced stress. (3) Results: The levels of chlorophyll a, chlorophyll b, chlorophyll a+b, and carotenoids were significantly reduced due to CA-induced stress. The addition of exogenous Si significantly alleviated this reduction. Under CA-induced stress, exogenous Si significantly increased the activities of ribulose-1,5-bisphosphate carboxylase, glyceraldehyde-3-phosphate dehydrogenase, fructose-1,6-bisphosphatase, fructose-1,6-bisphosphate aldolase, and transketolase. CA-induced stress significantly increased the fructose, glucose, and sucrose contents and reduced the starch content in the leaves and roots of seedlings. Similarly, the sucrose phosphate synthase, sucrose synthase, acid invertase, and neutral invertase activities were significantly reduced in plants under CA-induced stress. Overall, exogenous Si significantly reduced the soluble sugar content, increased the starch content, and promoted sucrose metabolism-related enzymatic activity in seedlings. (4) Conclusion: Exogenous Si can effectively increase the content of photosynthetic pigments in leaves of seedlings and maintain the balance of osmotic potential in the plant by reducing the accumulation of carbon assimilation products, which ultimately promotes tolerance to CA-induced autotoxicity stress. [ABSTRACT FROM AUTHOR]

Miscanthus lutarioriparius is a species of bioenergy crop unique to China. It is widely distributed in the south of China with high resistance to drought and salt stress. To date, the molecular mechanism of the adaption to drought stress in M. lutarioriparius is little known. In this study, RNA-seq technology was employed to analyze the transcriptome changes of diploid and tetraploid M. lutarioriparius after drought treatment. It was found that the number of differentially expressed genes in diploid M. lutarioriparius was much higher than tetraploid, whereas the tetraploid M. lutarioriparius may require fewer transcriptional changes. While the transcriptional changes in drought-tolerant tetraploid M. lutarioriparius are less than that of diploid, more known drought-tolerant pathways were significantly enriched than drought-sensitive diploid M. lutarioriparius. In addition, many drought-tolerance-related genes were constitutively and highly expressed in tetraploid under either normal condition or drought stress. These results together demonstrated that drought-tolerant tetraploid M. lutarioriparius, on the one hand, may preadapt to drought by constitutively overexpressing a series of drought-tolerant genes and, on the other hand, may adapt to drought by actively inducing other drought-tolerant-related pathways. Overall, this study could deepen our understanding of the molecular mechanism of drought-tolerance in bioenergy plants. [ABSTRACT FROM AUTHOR]

Supplementary light exposure using light-emitting diodes (LEDs) promotes the growth of tomato plants in greenhouses. Owing to the biological clock in plants, determining the period during which they must be exposed to supplementary light is essential to enhance growth. In this study, we used red and blue LEDs (red:blue = 7:2) as the supplementary light source, to determine the effects of different light supplemental periods on the growth and photosynthetic characteristics of tomato seedlings. Light supplementation in the morning and evening promoted the growth of tomato plants to varying degrees, including the accumulation of photosynthetic products in the leaves. Light supplementation in the morning enhanced dry matter accumulation, root growth, and the contents of chlorophyll and carotenoids in the leaves. Although both morning and evening light supplementation increased the levels of gas exchange parameters and Rubisco activity in tomato leaves, these effects were more prominent after morning light supplementation. Furthermore, red and blue light supplementation in the morning pre-activated the key photosynthetic enzymes, promoted the synthesis and accumulation of photosynthetic pigments, increased the photosynthetic capacity of, and photosynthate production in, tomato leaves. These findings suggest that light supplementation in the morning is more effective in promoting the growth and development of tomato plants cultivated in greenhouses. [ABSTRACT FROM AUTHOR]

The induced draft (ID) fan is an important piece of auxiliary equipment in coal-fired power plants. Early fault detection of the ID fan can provide predictive maintenance and reduce unscheduled shutdowns, thus improving the reliability of the power generation. In this study, an adaptive model was developed to achieve the early fault detection of ID fans. First, a non-parametric monitoring model was constructed to describe the normal operating characteristics with the multivariate state estimation technique (MSET). A similarity index representing operation status was defined according to the prediction deviations to produce warnings of early faults. To deal with the model accuracy degradation because of variant condition operation of the ID fan, an adaptive strategy was proposed by using the samples with a high data quality index (DQI) to manage the memory matrix and update the MSET model, thereby improving the fault detection results. The proposed method was applied to a 300 MW coal-fired power plant to achieve the early fault detection of an ID fan. In addition, fault detection by using the model without an update was also compared. Results show that the update strategy can greatly improve the MSET model accuracy when predicting normal operations of the ID fan; accordingly, the fault can be detected more than 4 h earlier by using the strategy with the adaptive update when compared to the model without an update. [ABSTRACT FROM AUTHOR]

With the expansion of the area under Cruciferae vegetable cultivation, and an increase in the incidence of natural threats such as pests and diseases globally, Cruciferae vegetable losses caused by pathogens, insects, and pests are on the rise. As one of the key metabolites produced by Cruciferae vegetables, glucosinolate (GLS) is not only an indicator of their quality but also controls infestation by numerous fungi, bacteria, aphids, and worms. Today, the safe and pollution-free production of vegetables is advocated globally, and environmentally friendly pest and disease control strategies, such as biological control, to minimize the adverse impacts of pathogen and insect pest stress on Cruciferae vegetables, have attracted the attention of researchers. This review explores the mechanisms via which GLS acts as a defensive substance, participates in responses to biotic stress, and enhances plant tolerance to the various stress factors. According to the current research status, future research directions are also proposed. [ABSTRACT FROM AUTHOR]

NaV2O5 mesocrystals were successfully synthesized from an alkaline-stripped pentavalent vanadium solution through a novel hydrothermal hydrogen reduction process. The optimal conditions for the hydrogen partial pressure, reaction temperature, initial solution pH value, and reaction time for the pure-phase NaV2O5 synthesis were ascertained to be 4 MPa, 200 °C, 4.0, and 2 h, respectively. The synthesis time (only 2 h) was greatly shortened, by nine times, compared with the most time-saving (18 h) hydrothermal process at present. X-ray diffraction (XRD) analysis revealed that the as-prepared powders demonstrated a typical layered orthorhombic structure of NaV2O5. The purity of the as-prepared NaV2O5 reached up to 99.98%. An electrochemical test showed that the as-prepared NaV2O5 has a potential application in sodium ion batteries. According to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses, the as-prepared NaV2O5 powders were identified to have rod-like mesocrystals consisting of small rods which preferentially grow along the (010) direction. Furthermore, the phase transformation mechanism and crystal growth mechanism in NaV2O5 preparation were discussed systematically, based on which the synthesis mechanism of NaV2O5 was proposed as pentavalent vanadates pre-sedimentation, hydrogen reduction with dehydration, sodium ions insertion, and finally self-assembly oriented attachment. The synthesis process is characterized as time-saving and low-cost, and thus it may have great application prospects. [ABSTRACT FROM AUTHOR]

The effects of sodium ions, phosphorus, and silicon on the eco-friendly process of vanadium precipitation by hydrothermal hydrogen reduction were investigated to establish the suitable concentrated solution system for this eco-friendly process. The results showed that sodium ions had no negative effects on the vanadium precipitation process. Phosphorus can reduce vanadate ion activity, and results in the decrease of vanadium precipitation percentage from 99.5% to 61.3%, as the phosphorus concentration in the feed solution increased from 0.05 g/L to 3 g/L. As a result, the aimed products of V2O3 were hard to be obtained, and the purity of the precipitates was lowered. Silicon can absorb in the form of H3Si3O7 on the surface of the precipitates, thus it was difficult for H (activity hydrogen atom) to react with the intermediate vanadium-bearing precipitates. As a result, the vanadium precipitation percentage decreased from 99.5% to 86.2% as the silicon concentration in the feed solution increased from 0.1 g/L to 3 g/L. The aimed products of V2O3 were not easy to be obtained, and only the intermediate vanadium-bearing precipitates containing sodium ions were obtained. The upper limits of the concentrations of phosphorus and silicon in the feed V (V) solution were ascertained as 0.5 g/L and 0.1 g/L, respectively. As the concentrations of phosphorus and silicon in the purified alkaline-concentrated V (V) solution extracted from vanadium-bearing shale are usually below the upper limits of the concentrations, the eco-friendly process of vanadium precipitation by hydrothermal hydrogen reduction has a great application prospect in the field of vanadium extraction from vanadium-bearing shale. [ABSTRACT FROM AUTHOR]

The huge energy consumption of metro operations has become a significant challenge faced by the urban public transportation sector to achieve low-carbon development. Using Shenzhen as an example, this study has made efforts to quantify the metro's energy consumption and carbon emission intensity during the operation phase by using the Life Cycle Assessment approach. Furthermore, this study evaluates the actions that can be taken to reduce energy consumption and emissions. A comparative analysis between metros and other public transportation modes has also been conducted. The results show that the annual carbon emissions from the metro's operation phase in Shenzhen city increased from 63,000 t CO 2 e in 2005 to 1.3 Mt CO 2 e in 2021, and the historically accumulated carbon emissions are 9.5 Mt CO 2 e. The unit operating mileage, the unit station area, and the per capita carbon emission intensity were 2.1 kg CO 2 e/km, 132.5 kg CO 2 e/m 2 , and 0.6 kg CO 2 e per capita (13th Five-Year Plan Period), respectively. By continually promoting the low-carbon operation of the subway, the cumulative carbon savings could reach 0.1 Mt CO 2 e (2022-2035).