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Soil quality has been defined as the capacity to sustain biological productivity and maintain environmental quality. Mowing and fertilization may affect ecosystem function through numerous soil properties, especially in semiarid grasslands where plant growth is limited by nutrient availability. However, the effects of grassland management on the trade‐off between soil quality and plant community structure is still unclear. Understanding the effect of land use type on soil quality is essential to adopt proper grassland management practices for a specific region. Principal component analysis was used to calculate a soil quality index (SQI) with 18 variables under the following treatments: control, mowing, nitrogen addition, and mowing plus nitrogen addition in August 2017 in a typical steppe of North China. This study showed that nitrogen addition significantly increased SQI by 0.82, field water capacity by 3.77%, soil capillary porosity by 3.30%, and soil available nitrogen content by 13.85 mg kg−1, but reduced soil aggregate proportion by 3.07%, microbial biomass nitrogen content by 7.74 mg kg−1, arbuscular mycorrhizal fungi by 0.02 μmol g−1, the ratio of fungus to bacteria by 0.16, and the ratio of Gram‐positive bacteria to Gram‐negative bacteria by 0.13 across the mowing and unmowing treatments. Nitrogen addition could improve productivity by increasing the soil quality but reduce plant diversity of the grassland ecosystems. Mowing did not affect SQI and aboveground biomass. The results suggested that fertilization as grassland management improved soil quality and productivity, whereas mowing was a sustainable way to maintain plant diversity in this semiarid grassland. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of annual net primary productivity (ANPP) and rain‐use efficiency (RUE) along precipitation gradients is critial for grassland conservation under climate change. However, how ANPP and RUE respond to changes in precipitation at different spatial and temporal scales remains uncertain. The aim of this research was to clarify these things. Using data from 21 field experiments, with an average sampling period of 14.3 years in 32 sites, 18 of which are in China, we evaluated the relationship of mean annual precipitation (MAP) with ANPP and RUE across spatial and temporal scales in grassland ecosystems. Our study showed different degrees of sensitivity of ANPP and RUE to changing precipitation spatially and temporally. First, analysis supports the well‐known positive linear relationship between ANPP and MAP. Second, we found that ANPP increases with increasing precipitation regardless of the actual precipitation amount of the study sites, whereas ANPP increased 0.2 g m−2 more than it declined per 1 mm change in precipitation. Third, RUE increased with increasing MAP across sites, whereas RUE generally decreased with annual precipitation within most sites. Finally, the temporal variation in RUE within sites is lower than the overall spatial pattern of variation across sites. The lack of consistency in ANPP and RUE among years and across sites in response to interannual variation in precipitation indicates the complexity of ecological indicators characterizing precipitation changes. These findings highlight the prevalence of site‐specific variation in precipitation‐ANPP relationships. [ABSTRACT FROM AUTHOR]

Questions: Changes in precipitation can influence grassland productivity and its sensitivity to precipitation variation, but general patterns remain elusive. Methods: Using data from 59 studies of experimental precipitation manipulations in grasslands, we tested the effect of increases and decreases in precipitation on above‐ground net primary productivity (ANPP), below‐ground net primary productivity (BNPP), forb and grass productivity, and their sensitivity to changes in precipitation. Results: Our results demonstrated that: (a) ANPP sensitivity to increases in precipitation was 87.3% greater than to decreases in precipitation, whereas there was no difference in the sensitivity of BNPP to increases and decreases in precipitation; (b) the sensitivity of grasses was 315.5% higher to decreases in precipitation than to increases in precipitation, but there was no difference in the sensitivity of forbs to increases and decreases in precipitation; (c) the sensitivity of ANPP to increases and decreases in precipitation was 620.8% and 91.7% higher than that of BNPP, respectively; (d) the sensitivity of grasses to precipitation decreases was 157% higher than that of forbs, but there was no difference in the sensitivity of grasses and forbs to increases in precipitation; and (e) the sensitivity of ANPP to increases in precipitation and BNPP to both increases and decreases in precipitation reduced with increasing mean annual precipitation (MAP), and the reduced magnitude in BNPP sensitivity was higher to precipitation increases than to precipitation decreases. In contrast, neither grass nor forb sensitivity varied with changes in MAP. Conclusions: Our study suggests that grassland productivity and its sensitivity to changes in precipitation not only depend on the magnitude of precipitation but also on the direction of precipitation change. These findings are important for the management of grasslands under future precipitation change scenarios. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to the optimization problem of conductor size selection in planning radial distribution systems. In this study, a multisection, branching feeder model with nonuniform load distribution has been chosen to best approximate actual conditions found in most distribution systems. Since the optimization problem is formulated as an integer programming problem, it is difficult to solve such a large-scale problem accurately. Therefore, in order to find an approximately optimal solution quickly, the authors have developed a simple, practical approach, which relies on the combined usage of an economical current density based method and a heuristic index directed method. This approach needs no sophisticated optimization technique and, thus, is easy to implement. Because of the practicality of its features, the proposed approach can be a usehd tool for distribution engineers. It is presently in use at several electric power bureaus, such as the Chongqing Electric Power Bureau in China. The detailed results of the designs of some typical radial feeders using the proposed approach are also presented and discussed.

In this paper, the structural, elastic, electronic and thermodynamic properties of and intermetallic compound are investigated using pseudopotential method based on density functional theory (DFT) under pressure. In this work, the calculated lattice constant and bulk modulus are in accordance with experimental values at zero temperature and zero pressure. The bulk modulus , shear modulus and Young's modulus for and increase with the increasing external pressure. It is noted that of investigated compound has the largest , and . The results of and have the same change trend, but presents an irregular change for and . The density of states for and are investigated at 0, 30 and 50 GPa. In addition, the thermodynamic properties as a function of temperature at different pressure are also studied. [ABSTRACT FROM AUTHOR]

Using first-principle calculation in combination with the Chen-Möbius inversion method, we get the interfacial potentials of the [110]/[100] ( = , and ) interface system. Based on the interfacial potentials, we investigate the interfacial stability, misfit dislocations and tensile fracture of the semi-coherent interfaces of [110]/[100] ( = , and ). The different sizes of the misfit dislocation models are employed to compare the interfacial energy. Results indicate that [110]/[100] interface is more stable than [110]/[100] ( = and ). The analysis of different tensile fracture processes shows that the misfit dislocations play an important role in the fractures of interfaces between iron and transitional metal carbides. [ABSTRACT FROM AUTHOR]

Surface ozone (O3) pollution has adverse impacts on the yield of winter wheat. The North China Plain (NCP), one of the globally significant primary regions for winter wheat production, has been frequently plagued by severe O3 pollution in recent years. In this study, the effects of O3 pollution on winter wheat yield and economic impact were evaluated in the NCP during the 2015–2018 seasons using the regional atmospheric chemical transport model (WRF-Chem), O3 metrics including the phytotoxic surface O3 dose above 12 nmol m−2 s−1 (POD12), and the accumulated daytime O3 above 40 ppb (AOT40). Results showed that the modeled O3, exposure-based AOT40, and flux-based POD12 increased during the winter wheat growing season from 2015 to 2018. The annual average daytime O3, exposure-based AOT40, and flux-based POD12 were 44 ppb, 5.32 ppm h, and 1.78 mmol m−2, respectively. During 2015–2018, winter wheat relative production loss averaged 10.9% with AOT40 and 14.6% with POD12. This resulted in an average annual production loss of 12.4 million metric tons, valued at approximately USD 4.5 billion. This study enhances our understanding of the spatial sensitivity of winter wheat to O3 impacts, and suggests that controlling O3 pollution during the key growth stages of winter wheat or improving its O3 tolerance will enhance food security. [ABSTRACT FROM AUTHOR]

The Standardized Precipitation Evapotranspiration Index (SPEI) is a widely recognized and effective tool for monitoring meteorological droughts. However, existing SPEI datasets suffer from spatial discontinuity or coarse spatial resolution problems, which limits their applications at the local level for drought monitoring research. Therefore, we calculated the SPEI index at meteorological stations, combined with the Global Precipitation Measurement (GPM) Precipitation (Pre), Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST), ERA5‐Land Shortwave Radiation (SR), Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) datasets and Random Forest Regression (RFR) model, developed a high spatial resolution (1 km) SPEI (HSPEI) datasets with multiple time scales in mainland China from 2001 to 2022. Compared to other SPEI datasets, the HSPEI datasets have higher spatial resolution and can effectively identify the detailed characteristics of drought in mainland China from 2001 to 2022. Overall, the HSPEI datasets can be effectively applied to the research of different droughts in China from 2001 to 2022. [ABSTRACT FROM AUTHOR]

FeNiV alloys exhibit potential applications in magnetic, radiation-resistant, mechanical, and superconducting fields, however, the formation of the hard yet brittle sigma phase enriched with Fe and V hindered their application in extreme environments. Therefore, improving the mechanical properties of FeNiV alloys has been a crucial problem. In this study, a series of as-cast FeNiVAl x (values of x is 0, 0.1, 0.2, 0.3) medium-entropy alloys (MEAs) were fabricated by vacuum arc melting, and the evolution of microstructure and mechanical properties with different Al microalloying were investigated systematically. As the Al content increased, FeNiVAl x MEAs underwent a structural transformation from a dual-phase structure consisting of a FCC phase (46.4 %; phase content) and a sigma phase (53.6 %) at x=0 to a single BCC phase in FeNiVAl 0.3 , while the mechanical properties of the alloy show a decrease in strength and a significant increase in elongation. Notably, the FeNiV alloy exhibits the highest yield strength of 1851 MPa with 7.8 % ductility. In contrast, the FeNiVAl 0.2 alloy demonstrated superior comprehensive compressive properties, with a high yield strength of 1255 MPa and an exceptional ductility exceeding 50 % without fracturing. The elimination of the harmful sigma phase, coupled with the formation of BCC phase, contributes to the observed decrement in strength and increment in ductility. This study elucidates the intrinsic relationship between microstructure and mechanical properties with Al contents in FeNiVAl x alloys, providing insights for the design of MEAs with excellent strength-ductility balance through microalloying. • Microstructure evolution and mechanical properties of FeNiVAl x MEAs were investigated systematically. • As the Al content increased, the hard yet brittle sigma phase was eliminated, and the BCC phase was formed. • The FeNiVAl 0.2 and FeNiVAl 0.3 alloys demonstrated superior comprehensive compressive properties. • The deformation mechanisms of FeNiVAl x MEAs were revealed. [ABSTRACT FROM AUTHOR]

Analyzing the influencing factors of fine particulate matter and ozone formation and identifying the coupling relationship between the two are the basis for implementing the synergistic pollutants control. However, the current research on the synergistic relationship between the two still needs to be further explored. Using the Geodetector model, we analyzed the effects of meteorology and emissions on fine particulate matter and ozone concentrations over the "2 + 26" cities at multiple timescales, and also explored the coupling relationship between the two pollutants. Fine particulate matter concentrations showed overall decreasing trends on inter-season and inter-annual scale from 2015 to 2021, whereas ozone concentrations showed overall increasing trends. While ozone concentrations displayed an inverted U-shaped distribution from month to month, fine particulate matter concentrations displayed a U-shaped fluctuation. On inter-annual scale, climatic factors, with planet boundary layer height as the main determinant, have higher effects for both pollutants than human precursors. In summer and autumn, sunshine duration had the most influence on fine particulate matter, while planet boundary layer height was the greatest factor in winter. Fine particulate matter is the leading impacting factor on ozone concentrations in summer, and there were positive associations between them on both annual and seasonal scale. The impact of nitrogen oxides and volatile organic compounds for both pollutants concentrations varied significantly between seasons. The two pollutants concentration were enhanced by the interactions between the various components. On inter-annual scale, interactions between the planet boundary layer height and other factors dominated the concentrations of the two pollutants, whereas in summer, interactions between fine particulate matter and other factors dominated the concentrations of ozone. The study has implications for the treatment of atmospheric pollution in China and other nations and can serve as an important reference for the creation of integrated atmospheric pollution regulation policies over the "2 + 26" cities. [Display omitted] • Meteorology have stronger effects than emissions on inter-annual scale. • PM 2.5 plays the dominant role on O 3 formation in summer. • There is positive correlations between PM 2.5 and O 3 on inter-annual and inter-season scale. • Interactions between the factors exerted enhanced effects on the PM 2.5 and O 3 concentrations. [ABSTRACT FROM AUTHOR]

In this study, we simulated the spatial and temporal processes of a particulate matter (PM) pollution episode from December 10–29, 2019, in Zhengzhou, the provincial capital of Henan, China, which has a large population and severe PM pollution. As winter is the high incidence period of particulate pollution, winter statistical data were selected from the pollutant observation stations in the study area. During this period, the highest concentrations of PM2.5 (atmospheric PM with a diameter of less than 2.5 µm) and PM10 (atmospheric PM with a diameter of less than 10 µm) peaked at 283 μg m-3 and 316 μg m-3, respectively. The contribution rates of local and surrounding regional emissions within Henan (emissions from the regions to the south, northwest, and northeast of Zhengzhou) to PM concentrations in Zhengzhou were quantitatively analyzed based on the regional Weather Research and Forecasting model coupled with Chemistry (WRF/Chem). Model evaluation showed that the WRF/Chem can accurately simulate the spatial and temporal variations in the PM concentrations in Zhengzhou. We found that the anthropogenic emissions south of Zhengzhou were the main causes of high PM concentrations during the studied episode, with contribution rates of 14.39% and 16.34% to PM2.5 and PM10, respectively. The contributions of anthropogenic emissions from Zhengzhou to the PM2.5 and PM10 concentrations in Zhengzhou were 7.94% and 7.29%, respectively. The contributions of anthropogenic emissions from the area northeast of Zhengzhou to the PM2.5 and PM10 concentrations in Zhengzhou were 7.42% and 7.18%, respectively. These two areas had similar contributions to PM pollution in Zhengzhou. The area northeast of Zhengzhou had the lowest contributions to the PM2.5 and PM10 concentrations in Zhengzhou (5.96% and 5.40%, respectively). [ABSTRACT FROM AUTHOR]

Climate change has already affected and will continue to affect crop yields. It is essential to understand and predict how the changing climate is influencing crops. This study assessed the effects of climate change on winter wheat yields in a central province (Henan) of China by using the calibrated Agricultural Production Systems sIMulator (APSIM) and the daily climate projections for Global Climate Models (GCMs), under two future societal development pathways (SSPs), SSP126 (sustainable development with low level greenhouse gas emissions) and SSP585 (conventional development with high level greenhouse gas emissions). We found that the effects of climate change on winter wheat yield would have clear spatial and temporal variations. Climate change is expected to shorten the maturity period for winter wheat by 1.1 days dec−1 (days per decade) and 4.4 days dec−1 compared with the baseline scenario (2000–2014) under scenarios of SSP126 and SSP585, respectively. However, the flowering dates would be delayed, by 0.2 days dec−1 under the SSP126 scenario and by 0.6 days dec−1 under the SSP585 scenario. Yield showed no significant trend under both scenarios, except that it would be higher than baseline in most years. Compared with the baseline, the annual mean winter wheat yield under future climate change would increase 784 kg ha−1 (SSP126) and 332 kg ha−1 (SSP585) during the 2030s, 1172 kg ha−1 (SSP126) and 364 kg ha−1 (SSP585) during the 2060s, and 707 kg ha−1 (SSP126) and 533 kg ha−1 (SSP585) during the 2090s. In the SSP126 scenario, winter wheat yield would increase over most counties of Henan, especially during the 2060s. However, winter wheat yield would decline in northern Henan during the 2030s and 2090s under the SSP585 scenario. Our findings could help farmers develop adaptation measures for winter wheat to ensure food security in Henan and China. • The APSIM-wheat model was comprehensive calibrated in Henan, China. • Simulated spatiotemporal patterns in effects of climate on winter wheat phenology and yield. • Effects of climate change on winter wheat phenology of Henan were quantified. • Effects of climate change on winter wheat yield of Henan were quantified. [ABSTRACT FROM AUTHOR]

Ground-level ozone (O 3) has negative effects on agricultural crops. Maize is an important grain crop in China. The North China Plain (NCP) serves as the major crops' production area of China and experiences severe ozone pollution. Using the ground-level ozone simulated by an atmospheric chemistry transport model (WRF-Chem), we quantified the yield reduction and economic losses of maize during 2015–2018 over NCP based on exposure-response AOT40 (accumulation of hourly O 3 concentration exceed 40 ppb) and flux-response POD 6 (phytotoxic dose of ozone over 6 nmol m−2 s−1). Results showed that the ozone concentration, AOT40, and POD 6 clearly increased from 2015 to 2018 in growing season of maize over NCP. The four-year annual mean ozone concentration, AOT40, and POD 6 were 0.055 ppm, 18.02 ppm h, and 5.02 mmol m−2, respectively. At county level, the relative loss of maize yield (MRYL) based on AOT40 and POD 6 had clearly spatio-temporal differences in NCP. The average MRYLs of AOT40 and of POD 6 from 2015 to 2018 were 10.4% and 21.4%, respectively, and these reductions were associated with 2399 million and 5637 million US dollars, respectively. This study suggests that surface ozone increased the yield losses of maize, and indicates that further reductions in ozone concentrations can enhance the food security in China. • Compare exposure-response with flux-response ozone metrics of maize over NCP. • The first flux-response evaluation of the effect of ozone on maize production in China. • Annual mean relative yield loss estimated by AOT40 and POD 6 were 10.4% and 21.4%, respectively. [ABSTRACT FROM AUTHOR]

Aiming to attain porous carbon nitride photocatalysts with high specific surface area, abundant active sites, broad absorption range and effective electron-hole separation, we remove carbon rings from graphene and replace all the edge carbon atoms of the cavity with nitrogen atoms. The accurate electronic structures and exciton properties of the proposed materials are revealed by the ab initio many-body Green's function theory. Computational results show that the absorption of the designed materials can cover both the visible and the near-infrared light region. The exciton binding energies of the materials are one order of magnitude lower than those of the typical two-dimensional photocatalyst graphitic carbon nitride. Due to the formation of hydrogen bonds between pyridinic nitrogen atoms and water molecules during water splitting, the key excited-state proton-coupled electron transfer reactions are barrierless. These findings could serve as guidelines for the realization of high-performance metal-free two-dimensional photocatalysts. Graphene with suitable-size nitrogen-doped cavity can photocatalyze water-splitting reaction barrierlessly even without the metal co-catalyst. [Display omitted] • Graphene with suitable-size N-doped cavity can photocatalyze water-splitting reaction directly without metal co-catalyst. • New metal-free two-dimensional porous graphitic carbon nitrides with semiconducting features are designed. • The key excited-state proton-coupled electron transfer reactions on the new photocatalyst are barrierless. • The exciton binding energies of the new two-dimensional photocatalyst are rather low. • The new photocatalyst can utilize sun light efficiently with a large region of visible and near-infrared light absorbed. [ABSTRACT FROM AUTHOR]

Anthropogenic activities and the resulting climate change affect the type, structure, and function of ecosystems. Understanding vegetation dynamics related to anthropogenic activities and climate change is critical to address the terrestrial carbon cycle in the context of global warming. The objective of this study is to quantify the effects of human-induced land use and land cover change (LUCC) and LUCC-induced climate change on terrestrial net primary productivity (NPP) in the Yellow River Basin (YRB) during 2000–2020 using Weather Research and Forecasting (WRF) model and Integrated Biosphere Simulator (IBIS) model through different experimental scenarios. Results indicated that LUCC can cause an increase in NPP of 1.2 ± 0.67 gC m−2 yr−1 in YRB. The increased precipitation and decreased temperature due to LUCC showed weak negative effect on annual mean NPP in YRB (−0.2 ± 0.74 gC m−2 yr−1). The coupling of LUCC and LUCC-induced climate change increased annual mean NPP approximately 0.6 ± 0.86 gC m−2 yr−1. The impacts of LUCC and LUCC-induced climate change and their coupling effects on NPP were greatest in spring, increasing NPP by 5.1 ± 0.51, 3.4 ± 0.41, and 6.1 ± 0.79 gC m−2 yr−1, respectively. These findings provide important guidance for the sustainable and adaptive management of terrestrial ecosystems in river basin in the context of global change. • Effects of LUCC and its associated climate change on NPP in YRB were quantified. • LUCC and its associated climate can boost and decline NPP in YRB, respectively. • The coupling of LUCC and its associated climate change can enhance NPP in YRB. [ABSTRACT FROM AUTHOR]

• A new high-entropy intermetallics was found for the equiatomic CoCrFeNiSi system. • The disordering was quantitatively analyzed by Rietveld refinement of the X-ray and neutron diffraction profiles. • The structural disorder was identified with magnetic measurement and theoretical calculations. A novel intermetallic compound with a cubic crystal structure was successfully synthesized within the quinary system of CoCrFeNiSi, boasting an almost equiatomic chemical composition. The crystal structures of the intermetallics and the minor impurity phase has been meticulously investigated using X-ray diffraction (XRD), time-of-flight neutron diffraction and transmission electron microscopy. Magnetic measurements of this high-entropy intermetallic compound revealed that CoCrFeNiSi exhibits ferrimagnetic properties at room temperature. The structural disorder was investigated through theoretical calculations and magnetic moment measurements. [ABSTRACT FROM AUTHOR]

• The hydrogen iodide (HI) acid vapor is employed to remove surface impurities and a thin LiI layer was in situ generated concurrently. • The LiI layer exhibits surprising wetting behavior and high stability towards li metal and SSE. • Interface impedance sharply decreased from 6160 to 30 Ω cm2, and the critical current density (CCD) value achieved 1.5 mA cm−2 at room temperature. • Lithium symmetric battery can cycle steadily for 1000 h at a current density of 0.6 mA cm−2. With regard to solid-state electrolytes (SSEs), garnet-type Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZT) is a promising option due to its high ionic conductivity and steadiness against lithium metal. However, trace impurities, like Li 2 CO 3 or LiOH, can be easily formed on its surface under ambient atmosphere and significantly influence the conductivity. Herein, the hydrogen iodide (HI) acid vapor is employed to remove surface impurities and a thin LiI layer was in situ generated concurrently. The layer exhibits surprising wetting behavior and high stability towards Li metal and SSE. Benefiting from its unique characteristics, the interface resistance between the LLZT electrolyte and lithium electrode decreased from 6160 to 30 Ω cm2, and the critical current density (CCD) value achieved 1.5 mA cm−2 at room temperature. Specifically, the lithium symmetric battery can cycle steadily for more than 1000 h at a current density of 0.6 mA cm−2. Moreover, a cumulative Li plating capacity of 0.63 Ah cm−2 can be attained. The assembled solid-state batteries (SSBs) show outstanding cycling stability over prolonged cycles at 0.1 C (LiFePO 4 /LiCoO 2 @room temperature) and a high rate capacity (LiFePO 4 : 104.2 mAh g−1 at 0.8 C). This work provides a plausible approach to interfacial issues, thereby paving the path for tangible advancements in SSBs. [Display omitted] [ABSTRACT FROM AUTHOR]