Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions ...Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions affect EMF remain largely unknown.Here,we investigated variation in three measures of diversity(alpha diversity,community composition and network complexity)among rare,intermediate,and abundant taxa across a latitudinal gradient spanning five forest plots in Yunnan Province,China and examined their contributions on EMF.We aimed to characterize the diversity distributions of bacterial groups across latitudes and to assess the differences in the mechanisms underlying their contributions to EMF.We found that multifaceted diversity(i.e.,diversity assessed by the three different metrics)of rare,intermediate,and abundant bacteria generally decreased with increasing latitude.More importantly,we found that rare bacterial taxa tended to be more diverse,but they contributed less to EMF than intermediate or abundant bacteria.Among the three dimensions of diversity we assessed,only community composition significantly affected EMF across all locations,while alpha diversity had a negative effect,and network complexity showed no significant impact.Our study further emphasizes the importance of intermediate and abundant bacterial taxa as well as community composition to EMF and provides a theoretical basis for investigating the mechanisms by which belowground microorganisms drive EMF along a latitudinal gradient.展开更多
Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient ...Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity.展开更多
Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify...Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species.展开更多
The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)at...The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)attenuation behavior remain poorly understood.To address this gap,a thermodynamically controlled periodic coordination strategy is proposed to achieve precise modulation of magnetic nanoparticle spacing.This approach unveils the evolution of magnetic domain configurations,progressing from individual to coupled and ultimately to crosslinked domain configurations.A unique magnetic coupling phenomenon surpasses the Snoek limit in low-frequency range,which is observed through micromagnetic simulation.The crosslinked magnetic configuration achieves effective low-frequency EM wave absorption at 3.68 GHz,encompassing nearly the entire C-band.This exceptional magnetic interaction significantly enhances radar camouflage and thermal insulation properties.Additionally,a robust gradient metamaterial design extends coverage across the full band(2–40 GHz),effectively mitigating the impact of EM pollution on human health and environment.This comprehensive study elucidates the evolution mechanisms of magnetic domain configurations,addresses gaps in dynamic magnetic modulation,and provides novel insights for the development of high-performance,low-frequency EM wave absorption materials.展开更多
In recent years,soil acidification has been expanding in many areas of Asia due to increasing reactive nitrogen inputs and industrial activities,which may seriously affect the performance of various ecosystem function...In recent years,soil acidification has been expanding in many areas of Asia due to increasing reactive nitrogen inputs and industrial activities,which may seriously affect the performance of various ecosystem functions.However,the underlying patterns and processes of ecosystem multifunctionality(EMF)are largely unknown at different levels of pH,limiting our understanding of how EMF respond to drivers.This study aims to explore threshold of pH on changes in EMF and differences in the drivers for the changes in EMF on either side of each of the determined pH thresholds.We collected nutrient and environmental databases for raster-level sampling data,totaling 4,000 sampling points.Averaging and cluster-multiple-threshold approach were used to calculate EMF,then quadratic and generalized additive models and Mann-Whitney U were used to determine and test the pH thresholds for changes in EMF,structural equation modellings and variance partitioning analysis were used to explore the main drivers on changes in EMF.The pH threshold for EMF changes in Chinese terrestrial ecosystems is 6.0.When pH<6.0,climate was consistently more important in controlling the variation of EMF than other variables;when pH≥6.0,soil was consistently more important in controlling the variation of EMF than other variables.Specifically,when pH<6.0,mean annual temperature was the main factor in regulating the EMF variation;when pH≥6.0,soil moisture was the main factor in regulating the EMF variation.Our study provides important scientific value for the mechanism of maintaining EMF under global change.For example,with further increases in global nitrogen deposition,leading to increased soil acidification,there are different impacts on EMF in different regions.It may lead to a decrease in EMF in acidic soils and an increase in EMF in alkaline soils.This suggests different management strategies for different regions to maintain EMF stability in the context of future global changes.In the future,more attention should be paid to the biological mechanisms regulating EMF.展开更多
The ultra-lightweight and multifunction integrated thermal protection materials are critical for the de-velopment of hypersonic vehicles.Although various materials have been developed as potential thermal protection m...The ultra-lightweight and multifunction integrated thermal protection materials are critical for the de-velopment of hypersonic vehicles.Although various materials have been developed as potential thermal protection materials,most of them generally present a singular function.It is still challenging to meet the multifunctional requirements of ultra-lightweight,thermal insulation,electromagnetic interference(EMI)shielding,and high-temperature ablation resistance.Herein,a gradient C_(f)/(CrZrHfNbTa)C-SiC composite is designed and fabricated based on the bionic strategy of capillary adsorption and transport.The devel-oped gradient C_(f)/(CrZrHfNbTa)C-SiC composite is as light as 0.74 g/cm^(3),which shows excellent ablation resistance(-3.88μm/s at 2000℃).It also presents competitive thermal insulation performance with a back temperature below 152℃while enduring 1300℃on the front side.The thermal conductivity of the gradient composite is 0.202 W mr^(-1) K^(-1).Furthermore,the gradient C_(f)/(CrZrHfNbTa)C-SiC composite offers remarkable EMI shielding performance with mean total EMI shielding efficiency(SE_(T))larger than 45 dB in an ultra-wide frequency range of 0-100 GHz.The excellent multifunctional performance with ultra-lightweight makes the gradient C_(f)/(CrZrHfNbTa)C-SiC composite ideal thermal protection materials for hypersonic vehicles.This work provides a flexible strategy for constructing gradient composites for multifunctional applications.展开更多
Multifunctional semiconductors play an important role in developing advanced photoelectric technologies.In this work,based on an octahedral replacement strategy in chalcogenides,a new selenide semiconductor NaMn_(3)Ga...Multifunctional semiconductors play an important role in developing advanced photoelectric technologies.In this work,based on an octahedral replacement strategy in chalcogenides,a new selenide semiconductor NaMn_(3)Ga_(3)Se_(8)was rationally designed,and synthesized by the flux method.The compound crystallizes in the noncentrosymmetric(NCS)P_(6)space group,and is composed of unique prismatic[NaSe_(6)],octahedral[MnSe_(6)]and tetrahedral[GaSe_(4)]motifs,inheriting the stable three-dimensional framework built by the octahedral and tetrahedral units in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family.NaMn_(3)Ga_(3)Se_(8)shows the largest known secondary nonlinear optical(NLO)response of~2.1×AgGaS_(2)(AGS)in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family,and a high laser-induced damage threshold of~3.0×AGS.Meanwhile,the introduction of Mn2t with unpaired 3d electrons induces a strong red emission band(685–805 nm)under the excitation source of 496 nm,as well as a paramagnetic to antiferromagnetic(AFM)transition at 7.3 K.The results confirm that NaMn_(3)Ga_(3)Se_(8)possesses multifunctional features including significant NLO response,fluorescence emission and AFM properties,and illustrate that replacing octahedral units with approaching size and geometry(like[MgSe_(6)]and[MnSe_(6)])could be a feasible way to develop multifunctional chalcogenides.展开更多
With the continuously increasing awareness of energy conservation and the intensifying impacts of global warming, Personal Thermal Management (PTM) technologies are increasingly recognized for their potential to ensur...With the continuously increasing awareness of energy conservation and the intensifying impacts of global warming, Personal Thermal Management (PTM) technologies are increasingly recognized for their potential to ensure human thermal comfort in extreme environments. Biomimetic structures have emerged as a novel source of inspiration for PTM applications. This review systematically summarizes the biomimetic structures, phase change materials, manufacturing methods, and the performance of multifunctional PTM wearables. Firstly, it analyzes the biomimetic structures with thermal regulation and encapsulated phase change material functionalities from different dimensions, highlighting their applications in PTM. Subsequently, it outlines the conventional manufacturing methods incorporating various biomimetic structures, offering strategies for the production of PTM wearables. The review also discusses the typical performance characteristics of multifunctional PTM wearables, addressing the current demands in thermal management. Finally, opportunities and challenges in PTM field are proposed, proposing new directions for future research.展开更多
Maintaining community stability has profound positive impacts on the ecological functions and sustainable utilization of grassland ecosystems.Numerous studies have explored how community stability responds to climate ...Maintaining community stability has profound positive impacts on the ecological functions and sustainable utilization of grassland ecosystems.Numerous studies have explored how community stability responds to climate change and its relationship with plant species diversity.Nevertheless,the impact and underlying mechanisms of belowground ecosystem multifunctionality(BGEMF)on community stability along a precipitation gradient in alpine grasslands remain poorly understood.To address this knowledge gap,we conducted field surveys from 2015 to 2020,measuring plant species diversity,annual net primary productivity(ANPP),and soil physicochemical properties across 79 sites in alpine grassland ecosystems on the Qinghai-Xizang Plateau.Our findings highlight both plant species diversity(standardized total effect:32%)and BGEMF(standardized total effect:75%)had an indirect effect on stability viaregulating mean ANPP within alpine grasslands.Furthermore,mean annual precipitation substantially impacted both plant species diversity and BGEMF,subsequently affecting community stability.However,temperature had a strong negative regulatory effect on species diversity,the mean and variability of ANPP.Thus,we emphasized the pivotal role of plant species diversity and BGEMF in shaping community stability,and stated the imperative need for species conservation and BGEMF improvement to sustain alpine ecosystems in the face of ongoing climate change.展开更多
β-hemihydrate phosphogypsum(HPG)was used to replace a part of cement to prepare hemihydrate phosphogypsum-red mud concrete,effectively increasing the comprehensive use of red mud(RM)and HPG in the concrete.The effect...β-hemihydrate phosphogypsum(HPG)was used to replace a part of cement to prepare hemihydrate phosphogypsum-red mud concrete,effectively increasing the comprehensive use of red mud(RM)and HPG in the concrete.The effects of different RM and HPG contents on the flow properties,water absorption and strengths of HPG-RM concretes were investigated.The appropriate content of HPG reduces the water resistance of red mud concrete,enhances the cohesion and water retention,and effectively filled the pores to decrease the degree of free water erosion.The optimal HPG content was 5%,10%,and 10%for red mud concretes with 30%,40%,and 50%RM,respectively.HPG content has more significant effects on the 28 d strengths of HPG-RM concretes.This consequence is accordant with the effect of HPG content on the pore size and pore size distribution from MIP results.The SEM and XRD results show that a large amount of SO_(4)^(2-)and Ca^(2+)from HPG promote the volcanic ash effect of RM generating more favorable hydration products.However,excessive HPG generates more Ettringite to inhibit the generation of calcium silicate and albite,causing cracks in the concrete and deteriorating performance.展开更多
基金supported by the Fundamental Research Funds of Chinese Academy of Forestry(Nos.CAFYBB2022SY037,CAFYBB2021ZA002 and CAFYBB2022QC002)the Basic Research Foundation of Yunnan Province(Grant No.202201AT070264).
文摘Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions affect EMF remain largely unknown.Here,we investigated variation in three measures of diversity(alpha diversity,community composition and network complexity)among rare,intermediate,and abundant taxa across a latitudinal gradient spanning five forest plots in Yunnan Province,China and examined their contributions on EMF.We aimed to characterize the diversity distributions of bacterial groups across latitudes and to assess the differences in the mechanisms underlying their contributions to EMF.We found that multifaceted diversity(i.e.,diversity assessed by the three different metrics)of rare,intermediate,and abundant bacteria generally decreased with increasing latitude.More importantly,we found that rare bacterial taxa tended to be more diverse,but they contributed less to EMF than intermediate or abundant bacteria.Among the three dimensions of diversity we assessed,only community composition significantly affected EMF across all locations,while alpha diversity had a negative effect,and network complexity showed no significant impact.Our study further emphasizes the importance of intermediate and abundant bacterial taxa as well as community composition to EMF and provides a theoretical basis for investigating the mechanisms by which belowground microorganisms drive EMF along a latitudinal gradient.
基金supported by the National Key Research and Development Program of China (2022YFF1300705)the Key Research and Development Project of Guangxi,China (Guike AB24010051)+1 种基金the National Natural Science Foundation of China (42261011,32271730 and U20A2011)the Central Public Welfare Research Institutes,Chinese Academy of Geological Sciences (2023020)。
文摘Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity.
基金supported by the National Natural Science Foundation(32130068,32271634,and 32071597)CAS Key Laboratory of Forest Ecology and Silviculture,Institute of Applied Ecology,Chinese Academy of Sciences(KLFES-2025)。
文摘Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species.
基金supported by the National Natural Science Foundation of China(22265021,52231007,and 12327804)the Aeronautical Science Foundation of China(2020Z056056003)Jiangxi Provincial Natural Science Foundation(20232BAB212004).
文摘The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)attenuation behavior remain poorly understood.To address this gap,a thermodynamically controlled periodic coordination strategy is proposed to achieve precise modulation of magnetic nanoparticle spacing.This approach unveils the evolution of magnetic domain configurations,progressing from individual to coupled and ultimately to crosslinked domain configurations.A unique magnetic coupling phenomenon surpasses the Snoek limit in low-frequency range,which is observed through micromagnetic simulation.The crosslinked magnetic configuration achieves effective low-frequency EM wave absorption at 3.68 GHz,encompassing nearly the entire C-band.This exceptional magnetic interaction significantly enhances radar camouflage and thermal insulation properties.Additionally,a robust gradient metamaterial design extends coverage across the full band(2–40 GHz),effectively mitigating the impact of EM pollution on human health and environment.This comprehensive study elucidates the evolution mechanisms of magnetic domain configurations,addresses gaps in dynamic magnetic modulation,and provides novel insights for the development of high-performance,low-frequency EM wave absorption materials.
基金This work was supported by the Tianshan Programme of Excellence(2022TSYCCX0001)the National Key Program for Basic Research and Development(973 Program)(2012CB417101)。
文摘In recent years,soil acidification has been expanding in many areas of Asia due to increasing reactive nitrogen inputs and industrial activities,which may seriously affect the performance of various ecosystem functions.However,the underlying patterns and processes of ecosystem multifunctionality(EMF)are largely unknown at different levels of pH,limiting our understanding of how EMF respond to drivers.This study aims to explore threshold of pH on changes in EMF and differences in the drivers for the changes in EMF on either side of each of the determined pH thresholds.We collected nutrient and environmental databases for raster-level sampling data,totaling 4,000 sampling points.Averaging and cluster-multiple-threshold approach were used to calculate EMF,then quadratic and generalized additive models and Mann-Whitney U were used to determine and test the pH thresholds for changes in EMF,structural equation modellings and variance partitioning analysis were used to explore the main drivers on changes in EMF.The pH threshold for EMF changes in Chinese terrestrial ecosystems is 6.0.When pH<6.0,climate was consistently more important in controlling the variation of EMF than other variables;when pH≥6.0,soil was consistently more important in controlling the variation of EMF than other variables.Specifically,when pH<6.0,mean annual temperature was the main factor in regulating the EMF variation;when pH≥6.0,soil moisture was the main factor in regulating the EMF variation.Our study provides important scientific value for the mechanism of maintaining EMF under global change.For example,with further increases in global nitrogen deposition,leading to increased soil acidification,there are different impacts on EMF in different regions.It may lead to a decrease in EMF in acidic soils and an increase in EMF in alkaline soils.This suggests different management strategies for different regions to maintain EMF stability in the context of future global changes.In the future,more attention should be paid to the biological mechanisms regulating EMF.
基金support from the National Natural Science Foun-dation of China(Nos.52472114 and 52332003)the Pro-gram of Shanghai Academic/Technology Research Leader(No.23XD1424300)are greatly acknowledged.
文摘The ultra-lightweight and multifunction integrated thermal protection materials are critical for the de-velopment of hypersonic vehicles.Although various materials have been developed as potential thermal protection materials,most of them generally present a singular function.It is still challenging to meet the multifunctional requirements of ultra-lightweight,thermal insulation,electromagnetic interference(EMI)shielding,and high-temperature ablation resistance.Herein,a gradient C_(f)/(CrZrHfNbTa)C-SiC composite is designed and fabricated based on the bionic strategy of capillary adsorption and transport.The devel-oped gradient C_(f)/(CrZrHfNbTa)C-SiC composite is as light as 0.74 g/cm^(3),which shows excellent ablation resistance(-3.88μm/s at 2000℃).It also presents competitive thermal insulation performance with a back temperature below 152℃while enduring 1300℃on the front side.The thermal conductivity of the gradient composite is 0.202 W mr^(-1) K^(-1).Furthermore,the gradient C_(f)/(CrZrHfNbTa)C-SiC composite offers remarkable EMI shielding performance with mean total EMI shielding efficiency(SE_(T))larger than 45 dB in an ultra-wide frequency range of 0-100 GHz.The excellent multifunctional performance with ultra-lightweight makes the gradient C_(f)/(CrZrHfNbTa)C-SiC composite ideal thermal protection materials for hypersonic vehicles.This work provides a flexible strategy for constructing gradient composites for multifunctional applications.
基金supported by the Natural Science Foundation of the Xinjiang Uygur Autonomous Region(2024D01E30)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0880000)+1 种基金the Open Fund of the Anhui Key Laboratory of Photonic Materials and Devices(AHKL2024KF02)the National Natural Science Foundation of China(22475234,22335007,22193044 and 22361132544).
文摘Multifunctional semiconductors play an important role in developing advanced photoelectric technologies.In this work,based on an octahedral replacement strategy in chalcogenides,a new selenide semiconductor NaMn_(3)Ga_(3)Se_(8)was rationally designed,and synthesized by the flux method.The compound crystallizes in the noncentrosymmetric(NCS)P_(6)space group,and is composed of unique prismatic[NaSe_(6)],octahedral[MnSe_(6)]and tetrahedral[GaSe_(4)]motifs,inheriting the stable three-dimensional framework built by the octahedral and tetrahedral units in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family.NaMn_(3)Ga_(3)Se_(8)shows the largest known secondary nonlinear optical(NLO)response of~2.1×AgGaS_(2)(AGS)in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family,and a high laser-induced damage threshold of~3.0×AGS.Meanwhile,the introduction of Mn2t with unpaired 3d electrons induces a strong red emission band(685–805 nm)under the excitation source of 496 nm,as well as a paramagnetic to antiferromagnetic(AFM)transition at 7.3 K.The results confirm that NaMn_(3)Ga_(3)Se_(8)possesses multifunctional features including significant NLO response,fluorescence emission and AFM properties,and illustrate that replacing octahedral units with approaching size and geometry(like[MgSe_(6)]and[MnSe_(6)])could be a feasible way to develop multifunctional chalcogenides.
基金supported by Basic and Applied Basic Research Foundation of Guangdong Province(No.2024A1515010772)State Key Laboratory of Massive Personalized Customization System and Technology,No.H&C-MPC-2023-02-06(Q)+2 种基金“CUG scholar”Scientific Research Funds at China University of Geosciences,Wuhan(No.CUG2022185)Guangzhou Youth Top Talent ProgramChina College Student Innovation and Entrepreneurship Training Program(No.S202410491063).
文摘With the continuously increasing awareness of energy conservation and the intensifying impacts of global warming, Personal Thermal Management (PTM) technologies are increasingly recognized for their potential to ensure human thermal comfort in extreme environments. Biomimetic structures have emerged as a novel source of inspiration for PTM applications. This review systematically summarizes the biomimetic structures, phase change materials, manufacturing methods, and the performance of multifunctional PTM wearables. Firstly, it analyzes the biomimetic structures with thermal regulation and encapsulated phase change material functionalities from different dimensions, highlighting their applications in PTM. Subsequently, it outlines the conventional manufacturing methods incorporating various biomimetic structures, offering strategies for the production of PTM wearables. The review also discusses the typical performance characteristics of multifunctional PTM wearables, addressing the current demands in thermal management. Finally, opportunities and challenges in PTM field are proposed, proposing new directions for future research.
基金supported financially by the National Natural Science Foundation of China(Grant No.32271774).
文摘Maintaining community stability has profound positive impacts on the ecological functions and sustainable utilization of grassland ecosystems.Numerous studies have explored how community stability responds to climate change and its relationship with plant species diversity.Nevertheless,the impact and underlying mechanisms of belowground ecosystem multifunctionality(BGEMF)on community stability along a precipitation gradient in alpine grasslands remain poorly understood.To address this knowledge gap,we conducted field surveys from 2015 to 2020,measuring plant species diversity,annual net primary productivity(ANPP),and soil physicochemical properties across 79 sites in alpine grassland ecosystems on the Qinghai-Xizang Plateau.Our findings highlight both plant species diversity(standardized total effect:32%)and BGEMF(standardized total effect:75%)had an indirect effect on stability viaregulating mean ANPP within alpine grasslands.Furthermore,mean annual precipitation substantially impacted both plant species diversity and BGEMF,subsequently affecting community stability.However,temperature had a strong negative regulatory effect on species diversity,the mean and variability of ANPP.Thus,we emphasized the pivotal role of plant species diversity and BGEMF in shaping community stability,and stated the imperative need for species conservation and BGEMF improvement to sustain alpine ecosystems in the face of ongoing climate change.
基金Funded by the National Natural Science Foundation of China(Nos.52168027 and 12362011)the Guizhou Province Science and Technology Innovation Talent Team Project(No.CXTD[2023]022)the Guizhou Province Science and Technology Support Project(No.[2022]027)。
文摘β-hemihydrate phosphogypsum(HPG)was used to replace a part of cement to prepare hemihydrate phosphogypsum-red mud concrete,effectively increasing the comprehensive use of red mud(RM)and HPG in the concrete.The effects of different RM and HPG contents on the flow properties,water absorption and strengths of HPG-RM concretes were investigated.The appropriate content of HPG reduces the water resistance of red mud concrete,enhances the cohesion and water retention,and effectively filled the pores to decrease the degree of free water erosion.The optimal HPG content was 5%,10%,and 10%for red mud concretes with 30%,40%,and 50%RM,respectively.HPG content has more significant effects on the 28 d strengths of HPG-RM concretes.This consequence is accordant with the effect of HPG content on the pore size and pore size distribution from MIP results.The SEM and XRD results show that a large amount of SO_(4)^(2-)and Ca^(2+)from HPG promote the volcanic ash effect of RM generating more favorable hydration products.However,excessive HPG generates more Ettringite to inhibit the generation of calcium silicate and albite,causing cracks in the concrete and deteriorating performance.
