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Perovskite type hydrides have emerged as a focal point in hydrogen storage applications as potential candidates in recent years. However, the currently synthesized perovskite hydrogen storage materials suffer from high hydrogen desorption temperatures and unstable reactions. To identify promising perovskite hydrogen storage materials, this study explores the hydrogen storage properties of XCrH 3 (X = Na, K) and KYH 3 (Y Mo, W) based on first-principles (FPs) calculations. The results indicate that NaCrH 3 and KCrH 3 exhibit half-metallic properties, while KMoH 3 and KWH 3 are metallic materials with high hydrogen storage safety. Mechanical property analysis reveals that NaCrH 3 exhibits the highest hardness, indicating better stability for hydrogen storage. Thermodynamic analysis shows that KCrH 3 has a lower hydrogen desorption temperature than the other three compounds, with NaCrH 3 having the second-lowest. The gravimetric hydrogen storage capacities of NaCrH 3 , KCrH 3 , KMoH 3 , and KWH 3 are 3.85 wt%, 3.21 wt%, 2.19 wt%, and 1.34 wt%, respectively. Overall, NaCrH 3 demonstrates superior gravimetric hydrogen storage capacity, stability, and safety, making it a promising candidate for new perovskite type hydrogen storage materials. • All four compounds are magnetic materials and stable. • NaCrH 3 exhibits the highest hardness with superior stability in hydrogen storage and release reactions. • NaCrH 3 has a higher gravimetric hydrogen storage capacity and a lower evolution temperature. • KWH 3 is a ductile material, and the other three are brittle materials. [ABSTRACT FROM AUTHOR]

MgB 2 has a wide range of applications as a crucial superconducting material in fields such as electronics and communications, but its weak mechanical properties limit its use in extreme environments such as high pressure. Therefore, this article explores the enhancement mechanism of the mechanical properties for MgB 2 by substituting Mg sites with Nb element based on first principles. After substitution, NbB 2 has better thermodynamic stability, and the introduction of Nb-d state enhances light absorption. In terms of mechanics, due to the higher electron accumulation density in the Nb–B bond and a shorter bond length (2.451 Å), the atomic interactions become tighter and stronger. As a result, both elastic constants and modulus are enhanced, exhibiting high stiffness, high compression resistance, etc. The spatial distribution of 3D elastic anisotropy is closer to a spherical shape and the universal anisotropy index (A U ) tends to approach 0, which indicates the mechanical properties in all directions are more consistent, making it easier to predict and control. Meanwhile, the elastic modulus rises smoothly with increasing hydrostatic pressure and is not affected by lattice compression at low hydrostatic pressure. The change rate of B–B bond length is 6.8 % at 100 GPa, which becomes the main reason for the enhancement of mechanical properties. The article provides a theoretical foundation for the preparation of superconductors with excellent mechanical properties under extreme conditions. [ABSTRACT FROM AUTHOR]

Root border cells (RBCs) and their mucilage are considered to play an important role in protecting root tip from aluminum (Al) toxicity, but their interactions with silicon (Si) under Al stress still remain unclear. Here, we investigated the effect of Si on the formation of RBCs under Al stress and the related detoxification mechanism in hydroponically grown rice (Oryza sativa L.). The results showed that Si could prevent the separation of RBCs from each other by increasing the degree of pectin methylesterification in root tip cell wall, thereby keeping more RBCs around the root tip. Also, Si maintained the viability of RBCs, increased the amount of mucilage, and reduced the content of total Al and free Al in root tips. Moreover, the RBCs accumulated more Al and Si simultaneously than root tip in the Al treatments with Si supply. Overall, these results indicated that Si reduced the toxicity of Al to RBCs through formation of Si–Al complex on the RBCs, thereby improving the viability of RBCs and promoting the secretion of mucilage. Concomitantly, Si, RBCs and their mucilage could form a protective sheath at the root tip, which prevented Al from diffusing into the root tip, thereby alleviating Al toxicity in rice root tips. [Display omitted] • Si kept more RBCs around the root tip under Al stress. • Si improved the viability of RBCs and promoted the production of mucilage. • The formation of Si–Al complex on the RBCs reduced the toxicity of Al to root tip. • A protective sheath formed by RBCs and mucilage prevented Al from entering root tip. [ABSTRACT FROM AUTHOR]

The layered structure of GeS exhibits commendable thermal stability and holds significant promise in the realms of optoelectronics and ion batteries. But its application is limited as dilute magnetic semiconductor. Therefore, this study delves into the impact of 3d transition metal (TM = V, Cr, and Mn) doping on the magnetic and optical characteristics of two-dimensional GeS monolayer through a first-principles calculation method grounded in density functional theory. The findings elucidate that all doping systems lead to a reduction in the band gap, with the V-doped system exhibiting the most significant diminishment. After doping process, magnetic coupling emerges between the electrons in the TM-3d state and those in the S-3p state, resulting in the manifestation of magnetic semiconductor characterized by magnetic moments of 3 μ B , 4 μ B , and 5 μ B , respectively. Comparative analysis with the pristine GeS monolayer, it reveals enhancements in optical absorptivity and refractive index within both the infrared and visible spectra of the doped systems. Notably, the V-doped system showcases superior optical properties due to its narrower band gap, facilitating more efficient electron transitions to the conduction band. Consequently, TM (TM = V, Cr, and Mn)-doped GeS monolayer hold promising potential in the realms of spintronics and optoelectronics. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic water splitting is of holds paramount importance in addressing contemporary energy and environmental challenges. The emergence of symmetry-deficient Janus two-dimensional materials has opened new avenues for advancing the field of photocatalytic hydrogen production. Using first-principles calculations, we investigated a novel Janus Zn 2 XY (X = S, Se; Y Se, Te; X≠Y) monolayer. The results demonstrate exceptional structural stability and favorable characteristics for water splitting, including direct band gaps and optimal band edge alignment. Spatially separating band edge states and the intrinsic vertical electric field effectively suppress the recombination rate of photogenerated electron-hole pairs. Strain engineering enhances the monolayer's capacity for visible light absorption. Furthermore, All Janus monolayers exhibit an impressive electron mobility of 103 cm2/V/s, with Janus Zn 2 STe and Zn 2 SeTe monolayers reaching 16.28% and 16.34% Solar-to-hydrogen (STH) efficiencies, respectively. These findings showcase the superior performance of Janus Zn 2 XY in water splitting and guide future experimental endeavors. [Display omitted] • Janus Zn 2 XY (X = S, Se; Y Se, Te; X≠Y) shows promise for water splitting. • They exhibit suitable bandgaps and edge alignments for water splitting. • Exceptional stability and high electron mobility characterize these materials. • In-built electric fields effectively suppress electron-hole recombination. • Strain is an effective strategy to improve their light absorption. [ABSTRACT FROM AUTHOR]

A molecular dynamics simulation is performed to investigate the icosahedron in Mg 70 Zn 30 metallic glass during solidification at the cooling rate of 1 × 10 13  K/s. It is found that the 1551, 1541 and 1431 bond-types are closely related to 13-atom icosahedron-like clusters. Two kinds of clusters are very similar to full icosahedron in geometry. The three clusters can transform into each other by changing one bond between a pair of outer atoms. One distorted icosahedron act as the intermediate between the two others. This work provides an insight into the glass formation in alloy from the cluster-level structural viewpoint and will shed light on developing more metallic glasses. [ABSTRACT FROM AUTHOR]

The mechanism by which temperature sensitivity (TS) of soil N 2 O emissions is increased by agricultural management with application of nitrogen fertilizer (AMN) is unclear. We hypothesized that a higher TS of N 2 O emission induced by AMN is the result of the faster growth of specific microorganisms in response to faster nitrogen (N) mineralization at higher temperatures. To test this hypothesis, we used reciprocal transplants to separate the contributions of abiotic and microbial components to the TS of N 2 O emissions in an arable soil receiving organic and inorganic fertilizers and its neighboring natural grassland soil treated with two levels of N. N 2 O sources were separated with acetylene, and the abundances of N 2 O-producing microbes were assessed by quantifying the copy numbers of the associated functional genes. Compared with natural soil, only changes in abiotic properties increased the Q 10 (the factor by which the rate increases with a 10 °C rise in temperature) by 105.7%, while changes in both abiotic and the microbiome increased the Q 10 by 225.2%. Higher TS of N 2 O emission in the arable soil induced by a microbiome shift was associated with faster N mineralization, increased proportion of nitrification-N 2 O emission, and faster growth of ammonia-oxidizing bacteria at higher temperatures. Addition of ammonium nitrate further enhanced the TS of N 2 O emissions, the proportion of nitrification-N 2 O emission, and the increased extent of the growth of ammonia-oxidizing bacteria in the soil with AMN compared to the natural grassland soil. Substrate-driven growth of ammonia-oxidizing bacteria with higher substrate preference contributes significantly to the higher TS of N 2 O emission caused by AMN. [ABSTRACT FROM AUTHOR]

Silicon (Si), as a beneficial element for a number of crops, can significantly improve the growth and yield of crops partly through silicon-enhanced resistance to biotic and/or abiotic stress. However, the mechanisms of Si-improved growth and fruit quality of horticultural crops, in particular, remain poorly understood. In the present study, two-year field experiments were conducted aimed at testing the effects of different sources of silicate fertilizers applied on table grape yield, fruit quality and fruit commercial characteristics during storage period. For this, two table grape cultivars were tested with treatments including: (I) no silicate fertilizer (control), (II) steel slag fertilizer and (III) water-cooling slag fertilizer. The application rate of silicate fertilizer was 600 kg SiO 2 ha −1 . Fruit yield, cluster weight, berry weight, berry size ( i.e. length and width) were significantly increased by application of silicon fertilizers ( P < 0.05) in both cultivars. Table grape fruit yield was 13.5% higher in the treatment with either water-cooling slag fertilizer or steel-slag fertilizer than in the control across the two years tested. Silicon fertilization significantly improved fruit total soluble solids, the ratio of total soluble solids to titratable acidity (TSS/TA) and fruit firmness. Applying silicate fertilizer significantly extended the fruit shelf-life by decreasing fruit respiratory intensity, decay incidence and weight loss ( P < 0.05). Water-cooling slag fertilizer did not show a significant difference from steel slag fertilizer in grape yield and fruit quality. Our findings suggest that silicate fertilizer could prolong fruit shelf-life and increase the yield and quality of grape in a calcareous grey desert soil. [ABSTRACT FROM AUTHOR]

Belowground biodiversity is essential for soil functioning, but the effect of belowground biodiversity loss on food safety is unknown. We investigated the loss of soil microbial diversity on insecticides accumulation in Brassica. We manipulated soil biodiversity using the dilution-to-extinction approach in a Brassica-soil-insecticide system, monitored microbial communities via high-throughput sequencing, and identified potential functional microbes. Compared with unsterilized soil, the richness of functional bacteria was reduced by 14.1%, 36.2%, 51.6% and 73.2%, respectively, in the corresponding sterilized soil inoculated with 1-, 10 −2 -, 10 −4 - and 10 −6 -fold diluted soil suspension. The acetamiprid and imidacloprid concentrations increased significantly in Brassica tissues grown in sterilized soil inoculated with 10 −6 -fold diluted suspension. A bacterial group predominated in functional microbes of soils inoculated with 1-, 10 −2 - or 10 −4 -fold diluted suspension, but the relative abundance declined in soil inoculated with a 10 −6 -fold diluted suspension. Our findings revealed that undesirable impacts by the loss of soil biodiversity at an intermediate level on the accumulation of soil contaminant in plants could be alleviated by microbial functional redundancy through disproportionally complementary growth of specific functional microbial taxa, but severe loss of soil biodiversity would threaten food safety. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the impacts of organic-supplementation of a chemical fertilizer for improving soil biological activity, particularly towards disease suppression, in a drip-irrigated cotton system. Over a two-year field-based trial, our study characterized effects of partial substitution of chemical fertilizer with two types and amounts of organic components on the size, activity, carbon utilization potential, and culturable groups of pathogenic and antagonistic microbiota. The total microbial community size increased with application of chemical fertilizer ( P < 0.05), and more so when chemical fertilizer was supplemented with organic amendments ( P < 0.05). Alteration of microbial biomass carbon to nitrogen ratio, and the ratio of culturable bacteria and fungi, indicated that increases in the microbial community were underpinned by changes in bacteria. Enzymatic activity was greater in soils receiving fertilizer with organic supplement ( P < 0.05). Multivariate analysis indicated that there was no influence of fertilizer treatments on carbon utilization profiles (CUPs; P > 0.05), but a strong year-effect was evident ( P < 0.05). The population size of Verticillium dahliae and Fusarium oxysporum decreased with organic amendments ( P < 0.05), whilst antagonistic Trichoderma spp. and Bacillus spp. were inversely correlated to the pathogen populations. Overall, the results of this exploratory study support partial substitution of inorganic fertilizer with organic manure or bio-organic fertilizer to promote suppression of cotton root diseases. Associated benefits on soil biological quality will further increase the sustainability of this agroecosystem. [ABSTRACT FROM AUTHOR]

Using a trial and error method to measure amorphous forming ability in the experiment is a complex and time-consuming process. Therefore, it is necessary to devise a method that can rapidly and accurately predict the amorphous forming ability. In this study, two models, artificial neural network and convolutional neural network, are proposed for the prediction of amorphous forming ability of various amorphous alloys. The prediction accuracy of the two models reached 0.77623 and 0.71693, respectively, both of which were more than 19% higher than the reported prediction accuracy of the 13 criteria. This result shows that artificial neural network and convolutional neural network models can accurately predict the amorphous forming ability of a variety of amorphous alloys and provide theoretical guidance for the development and preparation of amorphous alloys. [ABSTRACT FROM AUTHOR]

The foliar uptake and transport of formaldehyde into Bracket plants from air via leaves and roots to external water was investigated in an air–plant–water system. The results indicated that formaldehyde could be quickly taken up by plant tissues, and that formaldehyde accumulated in leaves could be released rapidly back into air when the formaldehyde level in air was diminished. This rapid reversible translocation of formaldehyde between plant leaves and air resulted in high formaldehyde concentrations in leaf dews, depending upon exposure levels of formaldehyde in air. Meanwhile, formaldehyde could be transported from air to plant rhizosphere solution through downward transport. The concentration of formaldehyde in rhizosphere solutions increased with exposure time and the formaldehyde level in air. The efficiency of the leaf extracts to break down formaldehyde increased, probably because of an increase in oxidative potential of the leaf extracts. Taken together, the main mechanism of formaldehyde loss in air can be attributed to the accumulation by (or breakdown in) plant tissues; the removal rate of formaldehyde from air reached 135 μg h −1 plant −1 in the experimental condition. [ABSTRACT FROM AUTHOR]

GaN is a promising third-generation semiconductor material for fabricating nanodevices with nanoscale dimensions. In particular, thick-film sensors fabricated with GaN nanoparticles (NPs) have good gas-sensing characteristics. This study used molecular dynamics simulation to investigate the effect of temperature and size on the structural morphology and surface recrystallization of GaN NPs during sintering. The diffusion behavior and changes in the structural morphology of atoms were analyzed based on the shrinkage ratio, mean square displacement, potential energy, and other methods. The results show that during sintering, the surface of two GaN NPs experienced recrystallization, which expanded with increasing temperature; however, the obvious sintering phenomenon occurred at 3000 K. Interestingly, the surface recrystallization of NPs exhibited a lamellar structure formed through a specific stacking method of the crystal structure. However, when the size of one of the two NPs was reduced, the small NP rapidly melted and was induced to crystallize into a complete NP (having the same crystal orientation as the large NP) by the large NP. Moreover, NPs underwent rigid-body rotation and relative rotation during sintering; however, plastic deformation and dislocations resulting from rotation were only found in the neck of NPs of the same size. The study results provide valuable insights at the atomic scale regarding the sintering of GaN NPs and a useful reference for preparing and processing nanodevices. [ABSTRACT FROM AUTHOR]

The effects of consecutive application of chemical fertilizer with or without organic fertilizer on soil N 2 O emissions and denitrifying community structure in a drip-irrigated field were determined. The four fertilizer treatments were (i) unfertilized, (ii) chemical fertilizer, (iii) 60% chemical fertilizer plus cattle manure, and (iv) 60% chemical fertilizer plus biofertilizer. The treatments with organic amendments (i.e. cattle manure and biofertilizer) reduced cumulative N 2 O emissions by 4.9–9.9%, reduced the N 2 O emission factor by 1.3–42%, and increased denitrifying enzyme activities by 14.3–56.2%. The nirK gene copy numbers were greatest in soil which received only chemical fertilizer. In contrast, nirS - and nosZ -copy numbers were greatest in soil amended with chemical fertilizer plus biofertilizer. Chemical fertilizer application with or without organic fertilizer significantly changed the community structure of nirK -type denitrifiers relative to the unfertilized soil. In comparison, the nirS - and nosZ -type denitrifier genotypes varied in treatments receiving organic fertilizer but not chemical fertilizer alone. The changes in the denitrifier communities were closely associated with soil organic carbon (SOC), NO 3 − , NH 4 + , water holding capacity, and soil pH. Modeling indicated that N 2 O emissions in this soil were primarily associated with the abundance of nirS type denitrifying bacteria, SOC, and NO 3 − . Overall, our findings indicate that (i) the organic fertilizers increased denitrifying enzyme activity, increased denitrifying-bacteria gene copy numbers, but reduced N 2 O emissions, and (ii) nirS - and nosZ -type denitrifiers were more sensitive than nirK -type denitrifiers to the organic fertilizers. [ABSTRACT FROM AUTHOR]

Ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) co-exist in soils. However, little is known about the effects of fertilization on the AOA and AOB communities and their relative contribution to soil nitrification. The objective of this field study was to determine the effects of four years of mineral and organic fertilizer (i.e., either cattle manure or biofertilizer) application on AOB and AOA in calcareous soil. The combined application of mineral and organic fertilizer (especially cattle manure) significantly increased the species richness (Chao1 and Ace) and α- diversity (Shannon index) of AOB ( P < 0.05) but not AOA ( P = 0.102). The AOA/AOB ratios were 1.64 and 1.19 in the unfertilized and the mineral fertilizer treatments, respectively. In contrast, the AOA/AOB rations were <1.0 in treatments with both mineral and organic fertilizer. These findings indicated that organic fertilizer increased AOB comparatively to AOA. Fertilizer addition was associated with significant shifts in the community structure of AOB ( P < 0.01) but had little effect on AOA. Soil potential nitrification rate were greatly increased by the application of either mineral fertilizer or mineral plus organic fertilizer ( P < 0.05). Moreover, potential nitrification rate were positively correlated with AOB abundance ( P < 0.001) but not AOA abundance ( P = 0.223). Variations in AOB community structure were closely associated with fertilizer-induced changes in soil pH, NH 4 + and SOC, whereas AOA community structure was only significantly correlated with SOC ( P = 0.040). Our findings suggest (i) that AOB is more sensitive than AOA to different fertilization regimes and (ii) that AOB contribute more than AOA to nitrification in this fertilized calcareous field soil. [ABSTRACT FROM AUTHOR]

In the realm of semiconductor materials, the integration of graphene (Gr) and gallium nitride (GaN) has emerged as a promising avenue for enhancing device performance. In this study, a Gr/GaN layered nanocomposite was constructed using molecular dynamics simulation and the LAMMPS code. Diamond abrasive was pressed into the composite at a speed of 50 m/s at 300 K, followed by ultrasonic vibration-assisted polishing on the (0001) plane along the [ 0 1 ‾ 10 ] direction. By rigorously exploring various factors such as number of Gr layers, vibration amplitudes, vibration frequencies and grinding speeds, the study elucidates the intricate mechanisms governing material removal and subsurface damage. Key findings reveal optimal processing conditions, including three layers of Gr, an amplitude of 5 Å, a vibration frequency of 80 GHz and a grinding speed of 100 m/s, which result in enhanced material removal rates and improved surface quality. Additionally, the insertion of Gr layers within the GaN matrix demonstrates a remarkable reduction in friction and wear rates, highlighting the potential for enhancing device reliability and performance. This comprehensive investigation not only advances our understanding of ultrasonic vibration-assisted grinding processes but also underscores the transformative impact of Gr/GaN composites in semiconductor device fabrication. [Display omitted] • Graphene-containing composites exhibit enhanced wear resistance and reduced wear rate. • Temperature and friction variations in UVAP resemble sinusoidal patterns. • The graphene layer presence results in nearly uniform thickness of the subsurface damage layer. • Higher amplitudes result in increased material removal, albeit with higher severity of subsurface damage layers. • Elevated velocities raise regional temperature, affecting atom removal quantity and subsurface quality. [ABSTRACT FROM AUTHOR]

The discovery of comammox Nitrospira has altered our perception of the nitrogen biogeochemical cycle. However, their functional importance compared to canonical ammonia oxidisers (i.e., ammonia-oxidising bacteria (AOB) and archaea (AOA)) in agricultural soils remains elusive, especially in acidic soils. Here, we assessed the functional importance of these functional guilds in nitrification and nitrous oxide (N 2 O) emissions in three acidic agricultural soils by using a range of nitrification inhibitors (acetylene, 3,4-dimethylpyrazole phosphate (DMPP) and different concentrations of 1-octyne) and monitored their community assemblage and population dynamics. The sensitivity of comammox Nitrospira clade A to 1-octyne varied across soils, highlighting that the inappropriate use of 1-octyne can lead to misestimation of comammox activity. AOA were key NH 3 oxidisers in the three soils, while AOB also contributed significantly to nitrification in one soil. In contrast, comammox Nitrospira always played a minor role in ammonia oxidation and N 2 O emissions, likely due to their low abundances, restricted cellular kinetic properties and N 2 O production mechanisms. Together, this study demonstrates that comammox Nitrospira play a less important role in ammonia oxidation and N 2 O production in acidic agricultural soils than AOA and AOB, thereby providing important novel insights into the mitigation of nitrogen fertiliser loss and N 2 O emissions. • Comammox play a minor role in NH 3 oxidation and N 2 O emissions in acidic arable soils. • AOB are functionally active in acidic agricultural soils. • The sensitivity of comammox Nitrospira clade A to 1-octyne varies across soils. [ABSTRACT FROM AUTHOR]

• The topologically close–packed (TCP) atoms dominate in undercooled Zr liquid. • The TCP atoms are energetic and structural favourable and then stabilize super-cooled liquid. • Three stages between TCP and BCC competition process can be observed. • Crystallization cannot occur until the TCP atoms with T 5 > 1/3 drops in number and interconnect. The crystallization of undercooled liquid zirconium (Zr) during isothermal relaxation was investigated by molecular dynamics simulation. In particular, the dynamic competition mechanism between the topologically close–packed (TCP) and body–centered cubic (BCC) structures during crystallization was deeply studied using the atomic energy, the pair distribution function and the largest standard cluster analysis (LaSCA). The study found that TCP clusters, rather than icosahedral clusters, play an important role in hindering the crystallization of the undercooled liquid. The TCP clusters with T 5 = n 5 /(n 4 + n 5 + n 6) > 1/3 (where n 4 , n 5 and n 6 represent the number of common neighbor sub-cluster: 444, 555 and 666 respectively) stabilize the undercooled liquid and prevent crystallization; while the other TCPs exhibits an evolution trend similar to that of BCC-like clusters. Furthermore, three stages of the competition process between TCP and BCC structures can be observed, and crystallization does not happen until the number of major TCP clusters with T 5 > 1/3 decreases and the average degree of interconnection among them weakens. [ABSTRACT FROM AUTHOR]

• With a crystallization-like E-T curve Ni 50 Ag 50 amorphization includes a LLT and a LST. • The average cutoff distance exported by LaSCA is useful in identifying state transitions. • LLT can be identified by the evolution of SRO and MRO structures, where MRO shows the glass feature. • In LST, TCP-based MRO and TLRO structures grow rapidly. • TCP structures reflect the essential nature of amorphous systems more effectively than ICOs. A molecular dynamics simulation of rapid cooling at a cooling rate of 1011 K/s for Ni 50 Ag 50 alloys was conducted. The rapid cooling process was analyzed by using the system energy, the pair distribution function, and the largest standard cluster analysis. It is found that with a crystallization-like energy curve the solidification of Ni 50 Ag 50 alloy experiences a liquid-liquid and a liquid-solid transition (LLT and LST), finally result in an amorphous solid. In LLT stage the topologically close-packed (TCP) short-range order structures of both crystal (S666) and glass (S555) increase; whereas only glass medium-range order structures are formed. TCP-based long-range order (LRO) structures of glass do not increase until the beginning of the LST. Even in solid (T < T g) the LRO parameter based on ICO structures fluctuates violently, while that based on TCP structures is quite stable. Therefore, TCP not only is the basic structural characteristics of disordered system but also reasonably represents the metastability of metallic glasses. These findings not only clarify the importance of LLT for the glass forming ability of alloys, but also fully demonstrate the effectiveness and necessity of TCP structures for describing the structure of amorphous systems. [ABSTRACT FROM AUTHOR]

Soil contamination by heavy metals has become a serious threat to global food security. The application of silicon (Si)-based materials is a simple and economical method for producing safe crops in contaminated soil. However, the impact of silicon on the heavy-metal concentration in plant roots, which are the first line in the chain of heavy-metal entering plants and causing stress and the main site of heavy-metal deposition in plants, remains puzzling. We proposed a process-based model (adsorption-diffusion model) to explain the results of a collection of 28 experiments on alleviating toxic metal stress in plants by Si. Then we evaluated the applicability of the model in Si-mitigated trivalent chromium (Cr[III]) stress in rice, taking into account variations in experimental conditions such as Cr(III) concentration, stress duration, and Si concentration. It was found that the adsorption-diffusion model fitted the experimental data well (R2 > 0.9). We also verified the binding interaction between Si and Cr in the cell wall using SEM-EDS and XPS. In addition, we designed a simplified biomimetic device that simulated the Si in cell wall to analyze the dual-action switch of Si from increasing Cr(III) adsorption to blocking Cr(III) diffusion. We found that the adsorption of Cr(III) by Si decreased from 58% to 7% as the total amount of Cr(III) increased, and finally the diffusion blocking effect of Si dominated. This study deepens our understanding of the role of Si in mitigating toxic metal stress in plants and is instructive for the research and use of Si-based materials to improve food security. [Display omitted] • Si reduces toxic metal concentration in shoots but sometimes increases it in roots. • The adsorption-diffusion model was developed to explain the effect of Si in roots. • Si exhibited dual roles in roots by increasing adsorption and blocking diffusion. • The intensity and duration of stress and Si concentration affected Si's function. [ABSTRACT FROM AUTHOR]

Silicon (Si) has been well-known to enhance plant resistance to heavy-metal stress. However, the mechanisms by which silicon mitigates heavy-metal stress in plants are not clear. In particular, information regarding the role of Si in mediating resistance to heavy-metal stress at a single cell level is still lacking. Here, we developed a hierarchical system comprising the plant, protoplast, and suspension cell subsystems to investigate the mechanisms by which silicon helps to alleviate the toxic effects of trivalent chromium [Cr(III)] in rice. Our results showed that in whole-plant subsystem silicon reduced shoot Cr(III) concentration, effectively alleviating Cr(III) stress in seedlings and causing changes in antioxidant enzyme activities similar to those observed at lower Cr(III) concentrations without silicon added. However, in protoplast subsystem lacking the cell wall, no silicon deposition occurred, leading to insignificant changes in cell survival or antioxidation processes under Cr(III) stress. Conversely, in suspension cell subsystem, silicon supplementation substantially improved cell survival and changes in antioxidant enzyme activities under Cr(III) stress. This is due to the fact that >95% of silicon was on the cell wall, reducing Cr(III) concentration in cells by 7.7%–10.4%. Collectively, the results suggested that the silicon deposited on the cell wall hindered Cr(III) bio-uptake, which consequently delayed Cr(III)-induced changes in antioxidant enzyme activities. This research emphasizes the significance of cell walls in Si-alleviated heavy-metal stress and deepens our understanding of silicon functioning in plants. Furthermore, the hierarchical system has great potential for application in studying the functioning of other elements in plant cell walls. [Display omitted] • A hierarchical system was developed to explore the Si functioning mechanism. • The system includes three subsystems: plant, protoplast, and suspended cell. • Si affects rice seedlings' antioxidant enzyme activity by reducing Cr(III) uptake. • Silicon presents different roles on protoplasts and suspension cells. • 95% of Si is on cell walls of suspension cells and acts as a defense barrier. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphene enables copper nanodroplets to form hexagonal close-packed layers. • The TCP atoms in copper nanodroplets hinders the formation of crystal atoms. • Graphene improves the temperature and life-time of the liquid–solid transition. • Graphene affects the nucleation work and crystallization pathway of nanodroplets. • Wettability can tune the temperature and lifetime of solid–liquid coexistence. The microstructure determines the macro properties, so the chemical and physical properties of nanoparticles can be tuned by changing their structures. A molecular dynamics simulation for the rapid solidification of Cu nanodroplets on the graphene sheet is conducted to investigate the effect of substrate on nanoparticles. The phase transition, structure evolution, and crystallinity are quantified by the potential energy, the largest standard cluster analysis, and Bond-orientation order parameters. It is found that the solidification is inhomogeneous and stepwise crystallization. Interestingly, originating from the graphene wettability, different solid–liquid coexistence states are obtained that may have the potential to modify the chemical and physical reactions on nanoparticles. The temperature of this solid–liquid coexistence state depends strongly on the structural evolution of crystallization and thus can be regulated by the wetting properties of the graphene substrate. These results significantly extend the fundamental understanding of heterogeneous nucleation in nanodroplets, providing important insights for designing and fabricating composite materials with multifunctional properties. [ABSTRACT FROM AUTHOR]

Silicon (Si) can alleviate salt stress by decreasing Na+ bypass flow in rice (Oryza sativa L.), however, the mechanisms underpinning remain veiled. In this study, we investigated the roles of OsLsi1 and OsLsi2 in Si-induced reduction of bypass flow and its resultant alleviation of salt stress by using lsi1 and lsi2 mutants (defective in OsLsi1 and OsLsi2, respectively) and their wild types (WTs). Under salt stress, Si promoted plant growth and decreased root-to-shoot Na+ translocation in WTs, but not in mutants. Simultaneously, quantitative estimation and fluorescent visualization of trisodium-8-hydroxy-1,3,6-pyrenetrisulphonic (PTS, an apoplastic tracer) showed Si reduced bypass flow in WTs, but not in mutants. Energy-dispersive X-ray microanalysis (EDX) showed Si was deposited at root endodermis in WTs, but not in mutants. Moreover, results obtained from root split experiment using lsi1 WT showed down-regulated expression of Si transport genes (OsLsi1 and OsLsi2) in root accelerated Si deposition at root endodermis. In summary, our results reveal that Si deposition at root endodermis and its resultant reduction of Na+ bypass flow is modulated by OsLsi1 and OsLsi2 and regulated by the expression of OsLsi1 and OsLsi2 , implying that root Si deposition could be an active and physiologically-regulated process in rice. • Si deposition at root endodermis reduces Na+ bypass flow and alleviates salt stress. • Root Si deposition is modulated by OsLsi1 and OsLsi2. • Down-regulated OsLsi1 and OsLsi2 accelerated endodermis Si deposition. • Si deposition in root could be an active and physiologically-regulated process. [ABSTRACT FROM AUTHOR]

The study of two-dimensional flexible materials in mechanic and optics has gained significant attention. By applying strain to modify the internal structure of materials, researchers can investigate the resulting mechanical and optical changes, offering exciting opportunities for further exploration in this field. The electronic structure, mechanical properties, and optical properties of the two-dimensional trigonal system Bi 2 Te 2 Se under biaxial strain regulation were investigated by using the first-principles plane pseudopotential plane wave method based on density generalized function theory. The analysis reveals that the energy bandwidth of Bi 2 Te 2 Se decreases with increasing strain until the band gap reaches 0 at 9% strain, causing the system to shift from a semiconductor to a conductor. The electronic density of states is primarily determined by the 6 p orbitals of Bi and 5 p orbitals of Te. With regards to its mechanical properties, Bi 2 Te 2 Se satisfies the mechanical stability criterion under different strains. As the strain increases from 0% to 6%, the material becomes increasingly brittle, with its interior transitioning from metallic to covalent bonds. However, the material toughness begins to improve from 6% to 9%, with the interior transitioning from covalent to metallic bonding. The performance improvement of Bi 2 Te 2 Se varies depending on the two electric field polarization vectors along [1 0 0] and [0 0 1] directions under strain. The material shows distinct application prospects in terms of absorption coefficient, reflectivity, refractive index, and lossiness under two directions. This paper provides a theoretical reference for the future mechanical and optical applications of Bi 2 Te 2 Se. [ABSTRACT FROM AUTHOR]

Trivalent chromium [Cr(III)] is a threat to the environment and crop production. Silicon (Si) has been shown to be effective in mitigating Cr(III) toxicity in rice. However, the mechanisms by which Si reduces Cr(III) uptake in rice are unclear. Herein, we hypothesized that the ability of Si to obstruct Cr(III) diffusion via apoplastic bypass is related to silicic acid polymerization, which may be affected by Cr(III) in rice roots. To test this hypothesis, we employed hydroponics experiments on rice (Oryza sativa L.) and utilized apoplastic bypass tracer techniques, as well as model simulations, to investigate 1) the effect of Si on Cr(III) toxicity and its obstruction capacity via apoplastic bypass, 2) the effect of Cr(III) on silicic acid polymerization, and 3) the relationship between the degree of silicic acid polymerization and its Cr(III) obstruction capacity. We found that Si reversed the damage caused by Cr(III) stress in rice. Si exerted an obstruction effect in the apoplast, significantly decreasing the share of Cr(III) uptake via the apoplastic bypass from 18% to 11%. Moreover, Cr(III) reduced silica particles' radii and increased Si concentration in roots. Modeling revealed that a 5-fold reduction in their radii decreased the diffusion of Cr(III) in apoplast by approximately 17%. We revealed that Cr(III) promoted silicic acid polymerization, resulting in the formation of a higher number of Si particles with a smaller radius in roots, which in turn increased the ability of Si to obstruct Cr(III) diffusion. This negative feedback regulatory mechanism is novel and crucially important for maintaining homeostasis in rice, unveiling the unique role of Si under Cr(III) ion stress and providing a theoretical basis for promoting the use of Si fertilizer in the field. [Display omitted] • Si in rice mitigates Cr(III) stress by obstructing Cr(III) uptake via apoplastic bypass. • Cr(III) reduces Si particle radius and increases root Si concentration. • A great number of smaller Si particles can improve their obstructing effect. • Si in rice alleviates Cr(III) stress via a negative feedback regulatory mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • A data-driven machine learning approach is proposed for predicting metallic glass forming ability. • A three-step feature selection method was devised to effectively filter out the best feature set. • Oversampling and non-linear transformation techniques are used to improve the imbalance distribution of the data set. • A design solution for enhanced metallic glass forming ability is proposed based on the SHAP method. Scientists have extensively studied metallic glasses (MGs) for their excellent properties and potential applications. However, the limited glass forming ability (GFA) of MGs poses a significant challenge in engineering fabrication, severely limiting their scope of application. Herein, we collected data from 167 peer-reviewed research articles and 2 commonly used datasets and constructed a comprehensive dataset containing 2085 data points. We employed gradient boosting algorithmic models, such as XGBoost, LGBoost, and AdaBoost, for selecting the best feature set and constructing the most effective model from among 118 feature parameters through techniques such as three-step feature selection method, ten-fold cross-validation, and grid search. As the uneven distribution of the original dataset significantly impacts the model's performance, we implemented five nonlinear transformation techniques and three oversampling techniques to improve the model. The results indicated that the nonlinear and oversampling techniques improved the model's performance by improving the distribution balance. Finally, we interpreted the constructed models through Shapley additive explanation, providing relevant rules concerning GFA. The techniques employed and the rules presented herein contribute to the statistical understanding of GFA and may facilitate the discovery of novel MGs. [ABSTRACT FROM AUTHOR]

Anammox are unusual members of the microbial community contributing to N losses via anaerobic ammonium oxidation. Anammox use nitrite as a substrate and produce hydrazine as an intermediate product. Up to date, the effects of dissolved oxygen and moisture dynamics on anammox potential and microbial community in agricultural soils were poorly understood. In this study, we investigated the interaction of dissolved oxygen and moisture contents as factors affecting the soil anammox process. The experiment had four fertilization treatments i.e. Control (CK), Chemical fertilizer (CF), Pig composted manure plus chemical fertilizer (PMCF), and Straw returned to soil plus chemical fertilizer (SRCF) with different water contents, 70%-FC, Alternate wetting and drying (AWD), Flooding I (D.O 5.8 mg L−1), and Flooding II (D.O 2.6 mg L−1). 15N-isotopic tracer technique was used to evaluate the anammox and denitrification rates. The results showed that the anammox rate ranged from the lowest 0.56 nmol N 2 ·g−1·h−1 in CF (with 70% FC water) to the highest rate of 1.47 nmol N 2 ·g−1·h−1 in SRCF (with flooding II). In water treatments, the average lowest and highest anammox rates were in the 70% FC (0.61 nmol N 2 ·g−1·h−1) and Flooding II (1.14 nmol N 2 ·g−1·h−1), respectively. Moreover, under soil treatments, the minimum average anammox rate was found in the PMCF (0.76 nmol N 2 ·g−1·h−1) and maximum in the SRCF (1.01 nmol N 2 ·g−1·h−1). Interestingly, anammox genes copy numbers were highest in alternate wetting and drying conditions under all fertilizer treatments rather than in continuous flooding. The phylogenetic analysis showed that Ca. Brocadia was dominating while some of Ca. Jettenia was also present. In conclusion, alternate wetting and drying could increase the number of anammox bacteria and microbial diversity. Unlabelled Image • Alternate wetting and drying (AWD) can enhance Anammox rate and microbial diversity. • Consistently higher dissolved oxygen can inhibit the Anammox process/activity. • Long-term application of pig manure can decrease the Anammox activity. • Anammox activity has a positive relationship with hydrazine gene abundance. [ABSTRACT FROM AUTHOR]

Abstract Phytoextraction is an attractive strategy for remediation of soils contaminated by heavy metal (HM), yet the effects of this practice on biochemical processes involved in soil nutrient cycling remain unknown. Here we investigated the impact of successive phytoextraction with a Cd/Zn co-hyperaccumulator Sedum alfredii (Crassulaceae) on potential nitrification rates (PNRs), abundance and composition of nitrifying communities and functional genes associated with nitrification using archaeal and bacterial 16S rRNA gene profiling and quantitative real-time PCR. The PNRs in rhizosphere were significantly (P < 0.05) lower than in the unplanted soils, and decreased markedly with planting time. The decrease of PNR was more paralleled by changes in numbers of copy and transcript of archaeal amoA gene than the bacterial counterpart. Phylogenetic analysis revealed that phytoextraction induced shifts in community structure of soil group 1.1b lineage-dominated ammonia-oxidizing archaea (AOA), Nitrosospira cluster 3-like ammonia-oxidizing bacteria (AOB) and Nitrospira -like nitrite-oxidizing bacteria (NOB). A strong positive correlation was observed between amoA gene transcript numbers and PNRs, whereas root exudates showed negative effect on PNR. This effect was further corroborated by incubation test with the concentrated root exudates of S. alfredii. Partial least squares path model demonstrated that PNR was predominantly controlled by number of AOA amoA gene transcripts which were strongly influenced by root exudation and HM level in soil. Our result reveals that successive phytoextraction of agricultural soil contaminated by HMs using S. alfredii could inhibit ammonia oxidation and thereby reduce nitrogen loss. Graphical abstract Unlabelled Image Highlights • Successive phytoextraction by S. alfredii significantly reduced the PNR in rhizosphere. • Successive phytoextraction decreased the abundance and activity of archaeal amoA gene. • Successive planting with S. alfredii obviously altered the structure of nitrifying community. • Root exudates of S. alfredii inhibited ammonia oxidation by decreasing ammonia-oxidizing microbe activity. [ABSTRACT FROM AUTHOR]

Abstract The nitrification inhibitor, 3,4-dimethylpyrazole phosphate (DMPP), can be used to reduce N 2 O emissions from agricultural ecosystems. However, the effectiveness of DMPP varies among soils, and this is due to both abiotic (e.g. soil properties) and biotic factors (e.g. ammonia oxidizers and denitrifier communities). Understanding the nature of these effects is necessary to improve the efficacy of DMPP, therefore encouraging wider adoption and environmental benefits. In particular, soil microbial properties associated with variation in efficacy remain largely unknown. In this study four contrasting arable soils (a grey desert soil, an alluvial paddy soil, a loess-formed paddy soil, and a red soil), were characterized based on DMPP inhibition of N 2 O emissions and associated microbial functional guilds. DMPP significantly inhibited nitrification and N 2 O emissions, with an average inhibitory rate ranging from 41.7% in a red soil to 90.0% in a grey desert soil. Ammonia oxidizing bacteria (AOB) and archaea (AOA) exhibited contrasting response patterns to DMPP addition. Notably, suppression of N 2 O emissions by DMPP only occurred alongside fluctuations in AOB abundance. However, when AOB were inhibited, AOA abundance increased. Soil-dependent response patterns to DMPP were observed for ammonia oxidizers and denitrifiers in terms of community structure. Partial least squares path modeling (PLS-PM) found that abiotic factors, particularly pH, and biological factors such as ammonia oxidizer communities, were closely linked to N 2 O emissions. Our findings provide evidence that: (i) DMPP effectively inhibits nitrification through inhibiting the abundance of AOB across soil types; (ii) releasing AOA from the competition with AOB allows AOA to efficiently grow and multiply, even under high ammonium conditions; and (iii) abiotic factors play a more important role than biotic factors in soil N 2 O emissions. Graphical abstract Image 1 Highlights • Reduction of N 2 O emissions by DMPP was attributed to AOB growth inhibition. • Inhibition of AOB grown by DMPP resulted in increased AOA abundance. • Release of AOA from competition with AOB allowed AOA growth in high N conditions. • Soil properties played a more important role in N 2 O emissions than microbial factors. [ABSTRACT FROM AUTHOR]

The urease inhibitor, N -( n -butyl) thiophosphoric triamide (NBPT), has been proposed to reduce synthetic fertilizer-N losses, including nitrous oxide (N 2 O) emissions from agricultural soils. However, the response of N 2 O emission to NBPT amendment is inconsistent across soils and associated microbial mechanisms remain largely unknown. Here we performed a meta-analysis of the effects of NBPT on N 2 O emissions and found NBPT significantly reduced N 2 O emissions in alkaline soils whereas no obvious effects exhibited in acid soils. Based on the finding of meta-analysis that pH was a key modifier in regulating the effect of NBPT on N 2 O emissions, we selected two arable soils differing in pH and conducted a microcosm study. In conjunction with measurement of N 2 O emission, community structure and abundance of functional guilds were assessed using T-RFLP and qPCR. Our results showed NBPT retarded urea hydrolysis and inhibited nitrification, but stimulated N 2 O emission in alkaline soil, whereas it exhibited no remarkable effects in acid soil, thereby only partly confirming the results of meta-analysis. Abundances of AOB and ureC -containing bacteria decreased, while abundance of AOA increased in both soils with NBPT addition. For acid soil, N 2 O emissions were significantly correlated with both abundances and community structures of AOA and ureC -containing bacteria, as well as abundance of AOB; for alkaline soil, abundances and community structures of AOB were correlated with N 2 O emission, as well as community structures of ureC -containing bacteria and archaea, indicating an inconsistent response pattern of community traits of N 2 O emissions-related functional guilds to NBPT between alkaline soil and acid soil. Our findings suggest that (i) efficacy of NBPT in N 2 O emission was mainly influenced by soil pH and (ii) variable effects of NBPT on N 2 O emission might originate not only from the direct effect of NBPT on community traits of urease-positive microbes, but from the indirect effect on ammonia oxidizers. [ABSTRACT FROM AUTHOR]

Quadruple Ti particles microstructure evolution by sintering. [Display omitted] • The sintering process of quadruple Ti particles is studied utilizing the MD method. • The initial arrangement of the particles affects the microstructure of the quadruple Ti particles. • The higher the sintering temperature, the easier the transformation of HCP-Ti into BCC-Ti. • A new calculation method of multiparticles fusion ratio is proposed. The sintering dynamics of binary particles have been extensively studied; however, the sintering behavior of multiparticles still needs further investigation because it plays a key role in many industrial processes and advanced technologies. Herein, we used molecular dynamics simulations to investigate the sintering dynamics of quadruple titanium (Ti) particles. We investigated two particle arrangement configurations of Ti particles, ααββ and αβαβ, at three sintering temperatures (900 K, 1300 K, and 2000 K) to explore the microstructural changes of Ti particles during sintering. Furthermore, we proposed a formula for calculating the fusion ratio of multiple particles. The results show that ααββ-Ti could retain its HCP structure when sintered at 1300 K and 900 K, whereas only BCC-Ti was observed after sintering at high temperatures. The effect of diffusion mechanisms was more substantial at high temperatures, and the higher the sintering temperature, the better the particle fusion effect. In addition to the effect of temperature on atomic migration, different particle arrangement configurations can impact atomic migration. [ABSTRACT FROM AUTHOR]

The presence of Schottky barriers at the metal-semiconductor interfaces has always been troubling people all over the world. Therefore, achieving Ohmic contacts for high-performance and energy-efficient Schottky devices becomes imminent. Bulk metals as electrodes usually produce a severe Fermi level pinning (FLP) effect due to the presence of dangling bonds on their surfaces. Here, our recent work shows that the FLP effect can be effectively suppressed in MoSi 2 N 4 (MSN) and WSi 2 N 4 (WSN) contact with seven two-dimensional (2D) metals. The measured n-type and p-type pinning factors S are 0.42, −0.63 for MSN, 0.43, −0.51 for WSN, respectively, indicating a weak FLP effect. We also confirm that Ohmic contacts can be achieved just by Van der Waals stacking. Ohmic contacts can be obtained for NbS 2 , TaS 2 , TaSe 2 , and VS 2 in contact with MSN and for NbS 2 , NbSe 2 , TaS 2 , and VS 2 in contact with WSN. Our work unveils that MSN/2D metals and WSN/2D metals contacts show great potential in high-performance Schottky electronic devices. • Our work shows that efficient Ohmic contacts can be achieved simply by van der Waals stacking without applying strain or external electric fields. • Our work demonstrates the measured pinning factors S are higher than other common two-dimensional materials. MoSi 2 N 4 and WSi 2 N 4 show a weak Fermi level pinning effect and promising application. • Our work provides a new technique for highly efficient ohmic contact in MoSi 2 N 4 /2D and WSi 2 N 4 /2D metals contacts. [ABSTRACT FROM AUTHOR]

Anaerobic ammonium oxidation (anammox) is an important process in many marine and paddy ecosystems. However, few studies have reported on the contribution to the nitrogen cycle of anammox and its dynamics in rice–wheat cropping systems with different fertilization regimes. Here, isotope tracing and molecular techniques were used to determine the potential rates of anammox and their association with bacterial abundance, diversity, and activity. Rice–wheat cropping systems at two sites in Jiangsu Province, China were selected and the treatments at each site were: 1) no fertilization (CK), 2) 100% chemical fertilization (CF), 3) pig manure compost plus 50% chemical fertilization (PMCF), and 4) straw plus 100% chemical fertilization (SRCF). The results revealed that anammox bacteria with high abundance were detected in both the wheat and rice seasons. The abundance of anammox in PMCF treatment was higher than that in SRCF treatment in both Changshu and Jintan. Moreover, the abundance of anammox bacteria in CF treatment was significantly higher than that in CK in Changshu. Analysis of anammox hydrazine synthase β subunit ( hzs-β ) gene sequences showed that in the rice season, the anammox bacteria Ca. Brocadia, Ca. Scalindua, and Ca. Jettenia were present. In contrast, all of the anammox hydrazine oxidase ( hzo ) genes were affiliated with Ca. Brocadia, suggesting that hzs genes are more representative of anammox biological diversity compared to hzo . Sequences from the PMCF treatment where affiliated with both Ca. Jettenia and Ca. Brocadia, and showed the highest diversity. Anammox activity was detected in both the wheat and rice seasons, but there were significant differences between seasons. The anammox rates were in the range 0.34 to 1.04 nmol dinitrogen gas ∙ g − 1 dry soil ∙ h − 1 , and 3.15 to 9.62% of dinitrogen gas emissions were attributed to anammox. However, no significant difference among the fertilizer treatments for anammox activity was found in the study. [ABSTRACT FROM AUTHOR]

Long-term intensive fertilization is a practice common around the world and gradually alters soil microbiome, however, its influences on the temporal resilience of soil multifunctionality to biodiversity loss and biodiversity-multifunctionality relationships remain poorly understood. Here, we manipulated soil biodiversity using the dilution-to-extinction approach to examine the temporal variability in individual functions, soil multifunctionality and their relationships with bacterial and fungal communities under different fertilization treatments during a 90-day re-colonization process. We found that organic fertilization accelerated the resilience of single functions and soil multifunctionality to biodiversity loss compared with mineral fertilization and unfertilized control. The fungal community was less resilient than bacterial community to disturbances caused by fertilization and dilution. Bacterial but not fungal diversity was significantly and positively related to multifunctionality, and the strength of the diversity-multifunctionality relationships in organic fertilized soil was 3- and 67-fold higher than that in unfertilized and mineral fertilized soil, respectively. Both organic and mineral nutrient inputs promoted copiotroph-dominated bacterial assemblages (including Proteobacteria and Bacteroidetes members) and suppressed oligotrophs (mostly Acidobacteria and Chloroflexi), which paralleled multifunctionality resilience patterns in fertilized soils. β-Diversity of bacterial copiotrophs alone or in combination was significantly related to changes in multifunctionality. Random forest analysis and structural equation modeling indicated that bacterial community diversity and composition along with soil carbon and nitrogen basically determined soil multifunctionality, with 70% of the variance in multifunctionality being explained. Rare taxa from the bacterial copiotrophs were particularly important for maintaining multifunctionality. Our results underline the importance of fertilization-induced shifts in microbial ecophysiological strategies for promoting the resilience of soil multifunctionality to biodiversity loss, and the need to preserve the diversity of rare copiotrophic taxa for stable provision of ecosystem functions under future environmental change. • Organic fertiliser promoted soil multifunctionality resilience to biodiversity loss. • Bacterial communities were more important than fungi for predicting multifunctionality. • Multifunctionality resilience reflected fertilization-induced ecophysiological shifts. • Rare copiotrophic bacteria played an over-proportional role in multifunctionality. [ABSTRACT FROM AUTHOR]

Anaerobic ammonium oxidation (anammox) and nitrite-dependent anaerobic methane oxidation (n-damo) are two nitrogen-cycle processes that have recently received more attention. However, few studies have been performed on the effects of different fertilizations in upland-cropping soil. Therefore, the objective of this work was to assess the effects of different fertilizations on the distribution and diversity of anammox and n-damo bacteria along the profiles of soil during wheat cropping season of the paddy-upland rotation system. In our study, a five-year fertilization (from 2010 to 2015) was conducted on a paddy-upland rotation field, with four fertilizer treatments: an unfertilized control (CK), chemical fertilizer (CF), pig manure plus 50% chemical fertilizer (PMCF), and rice straw plus 100% chemical fertilizer (SRCF). The quantitative PCR results showed that the total abundance of anammox and n-damo bacteria during the wheat cropping season were lower than those reported previously in paddy soils, and the abundance of anammox bacteria decreased with soil depth, but the abundance of n-damo bacteria remarkably increased. Long-term fertilization reduced the abundance of anammox bacteria in the 0–40 cm layer and that of n-damo bacteria in the 20–60 cm layer. Furthermore, Illumina high-throughput sequencing of the hzs B and pmo A genes was performed, showing that anammox bacteria were affiliated with “ Candidatus Brocadia” and n-damo bacteria were related to “ Candidatus Methylomirabilis oxyfera.” Diversity analysis demonstrated that the diversity of anammox bacteria increased with soil depth. Among the fertilizer treatments evaluated, pig manure plus 50% chemical fertilizer (PMCF) yielded the highest abundance and lowest diversity of anammox bacteria in the 20–60 cm layer. Moreover, fertilization diversified the community structure of anammox bacteria in deep soil. For n-damo bacteria, a higher diversity was found under chemical fertilization than under other treatments. Redundancy analysis showed that the community structure of anammox was mainly related to of total nitrogen and soil organic carbon and that of n-damo bacteria was mainly associated with NO 3 − content. Overall, soil depth and fertilization patterns influenced the distribution and diversity of anammox and n-damo bacteria by changing the soil properties. [ABSTRACT FROM AUTHOR]

Temperature is an important factor governing the community traits of N 2 O-emission related functional guilds (mainly autotrophic ammonia oxidizers and heterotrophic denitrifiers) and their activities. However, there have been few attempts to explore the broad response patterns of these guilds to temperature changes across arable soils. For this, a temperature-controlled (15, 25 and 35 °C) microcosm experiment was conducted using three arable soils (Fujian, Gansu, and Jiangsu) in China under two different fertilizations (no fertilization control (CK) and inorganic fertilization (NPK)). In conjunction with the measurement of N 2 O emission, the community structure and abundance of ammonia oxidizing archaea (AOA) and bacteria (AOB), as well as nirS - and nirK -denitrifiers were assessed using T-RFLP and quantitative PCR, respectively. The analysis of community traits indicated a consistent response pattern of AOAs to temperature in terms of guild abundance, and a consistent effect of inorganic fertilization on the abundance of AOBs, but soil-dependent response patterns to fertilization and temperature were found for nirS - and nirK -denitrifiers in terms of abundance and community structure. The correlation analysis suggested that AOAs possibly assumed a role in N 2 O emission in all the tested soils, and nirS -denitrifiers probably participated in N 2 O emission in both the Fujian and Gansu soil, while a considerable amount of N 2 O emission in the Jiangsu soil might have been derived from heterotrophic nitrification. [ABSTRACT FROM AUTHOR]

• The void defects significantly affect the deformation and plasticity in FeNiCrCoCu HEAs. • The deformation behavior reveals that the void is the main cause of initial strain. • The effects of different temperatures and strain rates on FeNiCrCoCu HEAs voids were explored. • The tensile strength significantly increases at a strain rate of 1010 s−1 compared to 109 and 108 s−1. While preparing and using high entropy alloys (HEAs), many defects such as voids are inevitably formed. The effects of voids on the mechanical properties of FeNiCrCoCu HEAs are investigated using molecular dynamics simulations. The evolution of voids is examined by using models with one or two voids considering different void sizes, applied strain rates, and temperatures. The results demonstrate that the existence of the voids does influence the mechanical properties of HEAs. The tensile strength of the single-void model is higher than that of double-void model. The stress–strain curves demonstrate that a larger initial void size could reduce the tensile strength. During the tensile deformation, all dislocation emission occurs initially from the surface of the void. However, it occurs between the two voids in double-void models, which causes the deformation of the voids. With temperature increases, the tensile strength decreases. Under various strain rates, the tensile strength slightly rises at strain rates ranging from 108to 109 s−1. However, it significantly increases at a strain rate of 109 to 1010 s−1. [Display omitted] The development of void defect in FeNiCrCoCu HEAs under the tensile process at 300 K and a strain rate of 109 s−1. (a) single-void model; (b) double-void model. [ABSTRACT FROM AUTHOR]

The increasing input of nitrogen (N) fertilizers has a considerable impact on agricultural soil carbon (C) cycling due to its influence on soil microbial abundance and assemblages. However, the microbial mechanism underlying the response of straw-induced priming effect to long-term N application remains an open question. Here, using soils with three N fertilization levels (0, 300, and 570 kg N ha−1 y−1) from a long-term experimental site, we established a 40-day microcosm experiment to investigate the priming effect of straw addition on SOM mineralization and the associated microbial activity and community composition. We found that long-term N application significantly inhibited soil respiration while increasing straw-induced priming effect. The soil microbial biomass (including bacterial and fungal abundance) decreased with increasing N levels, accompanied by decreased bacterial α -diversity and altered β -diversity. In addition, the N fertilization level significantly influenced bacterial and fungal indicator species that were sensitive to straw addition (si OTUs) and long-term N fertilization (ni OTUs), as well as their co-occurrence patterns. In the first three days of straw decomposition, long-term N fertilization decreased the oligotroph-to-copiotroph ratio of bacterial si OTUs. In contrast, long-term N fertilization increased this ratio on days 20 and 40, along with facilitated microbial investment in extracellular enzymes and microbial N demand. This caused a stronger "N mining" process and consequently enhanced the priming effect in soil exposed to long-term N fertilization at the later stage of incubation. Linking indicator species analysis with priming effect, these results advance our understanding of the complex C cycling in agricultural soils undergoing long-term nitrogen management. • N fertilization increased the relative abundance of specific copiotrophic bacteria. • The composition of indicator OTUs was determined by N fertilization level. • N fertilization level altered the co-occurrence patterns of indicator OTUs. • Response of straw-indicator OTUs to N fertilization echoed the change of priming effect. [ABSTRACT FROM AUTHOR]

Recently, SiC has gained considerable interest owing to its avant-garde nature and relevance in future applications. Molecular dynamics simulation was performed to investigate nanopolishing of three-body diamond abrasives on workpieces that had undergone cluster deposition and annealing processes. The coordination number, temperature, atomic distribution, kinetic energy, friction coefficient, crystallization, and average height of the workpiece were determined. Further, the effects of different polishing depths and polishing speeds on the physical properties of the workpiece were determined. Results show that polishing depth considerably affects the coordination number, surface morphology, friction coefficient, crystallization, and temperature of the workpiece. The surface of the workpiece was polished while maintaining the crystallization rate at a polishing depth of 20 Å. With an increase in the polishing rate, the coefficient of friction decreased, the temperature of the workpiece increased, and the polishing trajectory became clearer, with a better crystallization at 1 Å/ps. [Display omitted] • The workpiece undergoes the process of deposition and annealed. • Three three-body diamond abrasives are parallel to each other, more like a "brush". • Friction coefficient of the abrasive is related to the temperature of the workpiece. • The height of SDL region is closely related to polishing depth and speed. [ABSTRACT FROM AUTHOR]

The electronic structure and optical properties of Mo 2 C with different surface atomic layer thicknesses (SALTs) have been investigated by employing the plane wave ultra-soft pseudopotential method based on the first principles. It is found that the LDA density generalization approximation is most suitable for the optimization of the geometry of Mo 2 C, under which the lowest energy and most stable structure are obtained. As the SALT decreases, the hybridization of Mo-d and Mo-p electrons in the valence band forms strongly hybridized orbitals. It suppresses the photoelectron leap of and increases the band gap, allowing the conversion of Mo 2 C from metal to semiconductor. Therefore, the dielectric function, refractive index, reflection spectrum, and absorption spectrum can be improved by adjusting the SALT of Mo 2 C. These findings can provide a theoretical basis for improving and optimizing its photoelectronic properties. • The LDA density generalization approximation is most suitable for the optimization of the geometry of Mo 2 C. • The transformation of Mo 2 C from metallic to semiconductor properties was achieved by adjusting SALT. • Different SALT can effectively modulate the optical properties of Mo 2 C, increase the optical utilization. [ABSTRACT FROM AUTHOR]

• Detailed comparison and depiction of different wind field models are listed. • Four international standards for wind load in transmission system are compared. • Wind-induced electrical component failure model in transmission system is summarized. • Data-driven outage prediction model in distribution system is summarized. • Machine learning algorithms combination and zero-inflation handling are reviewed. Given that wind hazards pose a considerable damage to power system in various countries, researchers have developed methods for disaster prevention to diminish the vulnerabilities. This paper attempts to review the failure analysis procedure under the impact of wind hazards, considering the following attributes: wind field generation method, wind-induced electrical component failure model in transmission system, and building outage prediction model from data-driven view in distribution system. First, we compare the calculation of circulation and translation wind speed, with geographical, temporal and uncertainty factors of wind speed considered. Then, we introduce the wind-induced component failure models derived by wind load calculation and fragility curves. The application of the series reliability model in multiple cluster failures is briefly described. Finally, we summarize the applications of data analysis in building outage prediction models. The reviewed literature contains the statistical learning methods and machine learning methods. It is concluded that the frameworks for component-level failure model and user-level outage prediction model are well established. However, most of the studies still develop two models, separately. Future researchers may target at the hybrid application of both models to better provide fault analysis, prediction and emergency in power system under wind hazards. [ABSTRACT FROM AUTHOR]

Nitrogen addition to croplands greatly increases global emissions of the potent greenhouse gas nitrous oxide (N 2 O). Three ammonia-oxidizing functional guilds constitute the major producers of N 2 O in agricultural soils, but their relative contributions are still poorly understood, especially the newly discovered and widespread complete ammonia oxidizers (comammox). To fill this knowledge gap, we used three nitrification inhibitors: acetylene, 1-octyne, and 3,4-dimethylpyrazole phosphate (DMPP), to selectively suppress the activity of different ammonia oxidizer guilds to discriminate their relative contributions to N 2 O production in an alkaline arable soil. The results indicated that DMPP completely inhibited the growth of comammox Nitrospira clade A and ammonia-oxidizing bacteria (AOB) but promoted ammonia-oxidizing archaea (AOA) growth, while the abundance of comammox Nitrospira clade A increased in the presence of 1-octyne at high ammonium (NH 4 +) concentrations. AOB dominated N 2 O production in soils with inorganic NH 4 + amendment, followed by AOA, while comammox Nitrospira contributed to less than 3% of total N 2 O emissions with an N 2 O yield of ∼0.083% (N 2 O per molecule of nitrate). The abundance of comammox Nitrospira clade A was approximately two orders of magnitude lower than that of canonical ammonia-oxidizers. Phylogenetic analysis revealed that the majority of comammox Nitrospira clade A belonged to a new cluster that was separated from the known comammox bacterium. Taken together, our results clearly and strongly demonstrate that comammox Nitrospira play only a minor role in N 2 O emissions in a heavily fertilized alkaline arable soil. • Comammox Nitrospira only contributed to less than 3% of total N 2 O emissions from a heavily fertilized arable soil. • DMPP inhibited the growth of AOB and comammox Nitrospira clade A, but 1-octyne only inhibited the growth of AOB. • The growth of AOA was further increased when both AOB and comammox Nitrospira clade A were inhibited. [ABSTRACT FROM AUTHOR]

Root cell wall (RCW) remodeling induced by copper oxide nanoparticles (CuO NPs) and its consequences for root growth of lettuce (Lactuca sativa L.) were investigated in this study. The results showed that a low concentration of CuO NPs (5 mg L−1) stimulated reactive oxygen species (ROS) signaling, led to the degradation of pectin by H 2 O 2, and promoted root elongation by 22.1% by triggering RCW loosening. However, under treatment with a high concentration of CuO NPs (450 mg L−1), the unordered distribution of pectin homogalacturonan enhanced cell wall adhesion. Also, the increased xyloglucan and the decreased xyloglucan endotransglycosylase/hydrolase (XTH) activities caused cell wall stiffening, making it difficult for lettuce roots to extend. Meanwhile, the contents of hemicellulose and low-methylated pectin were increased remarkably due to the downregulation of the encoding genes XTH15 , XTH17 , XTH31 and the upregulation of PME3 , which provided abundant binding sites of RCW with CuO NPs. In addition, the accelerated development of the apoplastic barrier and root lignification blocked the absorption of CuO NPs, and the endodermal cell walls were doubled in thickness, greatly enhancing their retention capacity to CuO NPs. Taken together, the above findings suggest that CuO NPs have concentration-dependent effects on lettuce roots, which are associated with plant tolerance and mediated by RCW remodeling. [Display omitted] ● 5 mg L−1 CuO NPs enhanced root elongation of lettuce by root cell wall (RCW) loosening. ● 450 mg L−1 CuO NPs triggered RCW polysaccharides modifications which made lettuce roots difficult to extend. ● The encoding genes related to RCW remolding participated in the response of lettuce to CuO NPs. [ABSTRACT FROM AUTHOR]

Emissions of the greenhouse gas nitrous oxide (N 2 O) from soil are sensitive to many factors including temperature, nutrient status, pH and bulk-density. Interactions among these are complex, particularly in agricultural systems where fertilizer-addition has interactive influences across many soil properties. Under laboratory conditions, the temperature sensitivity of N 2 O emissions, as measured by Q 10 values (fractional change in rate with a 10 °C increase in temperature), was higher in soils receiving long-term fertilizer addition compared with control. Different fertilization regimes significantly influenced the emission pathways. Application of manure increased the proportion of potential N 2 O derived from denitrification although the incubation condition used in the present study might not be favorable for anaerobic denitrification. The abundance of archaeal amoA gene copies increased under all fertilizer treatments, but that of bacterial amoA only increased under mineral (NPK) fertilization. Meanwhile, abundance of nirS , nirK and nosZ only increased under OM and MNPK fertilization. T-RFLP analyses showed that both ammonia oxidizing and denitrifier community structures were altered by fertilization, but only the nirS community structure was sensitive to temperature change. Furthermore, a strong correlation was observed between nirS gene abundance and potential N 2 O emissions. Relationships between AOA, nirK gene abundances and potential N 2 O emission were significant but relatively weak. PLS path model revealed that besides direct effect, potential N 2 O emission was also indirectly influenced by temperature through mediation of NH 4 + concentration and nirS -type denitrifier. Our work suggests that warming-induced elevation of potential N 2 O emission could be strengthened by long-term application of fertilizers, especially organic manure, via shifting community abundance and structure of nirS -type denitrifier. [ABSTRACT FROM AUTHOR]