To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liqu...To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liquid separation for copper slag slurry,the liquid-phase part has a critical influence on removing NO_(x)and SO_(2).Also,the leached metal ions played a crucial role in the absorption of SO_(2)and NO_(x).Subsequently,the effects of single/multi-metal ions on NO_(x)removal was investigated.The results showed that the leached metal from copper converter slag(Al^(3+),Cu^((2+),and Mg^((2+))and KMnO_(4)had a synergistic effect on NO_(x)removal,thereby improving the NO_(x)removal efficiency.Whereas Fe^(2+) had an inhibitory effect on the NO_(x)removal owing to the reaction between Fe^(2+) and KMnO_(4),thereby consuming the KMnO_(4).Besides,SO_(2)was converted to SO_(4)^(2-) completely partly due to the liquid catalytic oxidation by metal ions.The XRD and XPS results indicated that the Fe(Ⅱ)species(Fe_(2)SiO_(4),Fe_(3)O_(4))in copper slag can react with H+ions with the generation of Fe^(2+),and further consumed the KMnO_(4),thereby resulting in a decrease in the NO_(x)removal.The characterization of the slags and solutions before and after reaction led us to propose the possible mechanisms.The role of copper slag is as follows:(1)the alkaline substances in copper slag can absorb SO_(2)and NO_(2)by KMnO_(4)oxidation.(2)copper slag may function as a catalyst to accelerate SO_(2)conversion and improve NO_(x)removal by synergistic effect between leached metal ions and KMnO_(4).展开更多
La0.9Sr0.1Ga0.8Mg0.2O3–？ （LSGM） electrolyte materials were synthesized by the solid state reaction method. The conductivity of LSGM materials was detected by four probe method, and it was 0.08 S/cm at 850 oC. Dens...La0.9Sr0.1Ga0.8Mg0.2O3–？ （LSGM） electrolyte materials were synthesized by the solid state reaction method. The conductivity of LSGM materials was detected by four probe method, and it was 0.08 S/cm at 850 oC. Dense and uniform films of LSGM materials were deposited by the magnetic sputtering on substrates of Si and La0.7Sr0.3Cr0.5Mn0.5O3–？ （LSCM）. The experimental results showed that the deposition rates dropped and the average grain sizes of the films enlarged with increase in the substrate temperatures. In the sputtering process, the LSGM film was deposited with preferred growth direction. After annealing, the preferred growth direction disappeared and the film surface became smoother and denser. Through observing the deposition process, deposition mechanism was proposed, which was consistent with a model of island growth.展开更多
Light is one of the most important environmental factors for plant growth and development.In relay cropping systems,crop layouts influence light distribution,affecting light use efficiency(LUE).However,the response of...Light is one of the most important environmental factors for plant growth and development.In relay cropping systems,crop layouts influence light distribution,affecting light use efficiency(LUE).However,the response of light interception,light conversion,and LUE for relay maize and relay soybean to different crop layouts remains unclear.We aimed to quantify the effect of crop layout on intraspecific and interspecific competition,light interception,light conversion,LUE,and land productivity between relay maize and relay soybean.We conducted a field experiment for four consecutive years from 2017 to 2020 in Sichuan province,China,comparing different crop layouts(bandwidth 2.0 m,row ratio 2:2;bandwidth 2.4 m,row ratio 2:3;bandwidth 2.8 m,row ratio 2:4),with sole maize and sole soybean as controls.The results showed that relay maize in the 2.0 m bandwidth layout had the largest leaf area index and plant biomass,the lowest intraspecific competitive intensity and the highest aggressiveness.Compared to a bandwidth of 2.0 m,a bandwidth of 2.8 m significantly decreased relay maize leaf area index by 11%and plant biomass by 24%,while a 2.4 m bandwidth caused roughly half these reductions.The 2.0 m bandwidth layout also significantly improved crop light interception and LUE compared to sole maize.The light interception,light interception rate,light conversion rate and LUE in relay maize all decreased significantly with increasing bandwidth,but they increased in relay soybean.The increased light transmittance to the lower and middle canopy with increasing bandwidth did not compensate for the loss of relay maize yield caused by increased intraspecific competition.However,it enhanced the yield of relay soybeans.Increasing the bandwidth by 80 cm increased the relay maize intraspecific competition by 580%,and reduced maize yield by 33%,light interception by 12%,and LUE by 18%.In contrast,the relay soybean intraspecific competition was reduced by 64%,and the soybean yield was increased by 26%,light interception by 32%and LUE by 46%.Relay cropping systems with a 2.0 m bandwidth optimize the trade-off between light transmittance and intraspecific competition of relay crops.These systems achieve the highest LUE,group yield and economic benefits,making them a recommended crop layout for the southwest regions of China.Our study offers valuable insights for developing strip relay cropping systems that maximize light utilization and contributes to the theoretical understanding of efficient sunlight use in relay cropping practices.展开更多
Chitosan/coconut (CTS/coconut) composite membranes were successfully prepared by the cross-linking reaction with glutaraldehyde and they were applied in eliminating heavy metals from aqueous solutions. The cross-linke...Chitosan/coconut (CTS/coconut) composite membranes were successfully prepared by the cross-linking reaction with glutaraldehyde and they were applied in eliminating heavy metals from aqueous solutions. The cross-linked membranes were obtained at the ratios of 1/1, 1/1.5 and 1/2 and the coconut fiber was chemically treated by NaOCl/NaOH. The best ratio of CTS/coconut fiber is found to be 1/1.5 which has a relatively high stability with the degree of swelling (DS) and solvent content (SC) of membrane to be 13.33% and 69.88%, respectively. The results also indicate that the CTS membranes showed preferential separation of heavy metals for blend CTS/coconut membranes.展开更多
Wearable electronic textiles(e-textiles)with embedded electronics offer promising solutions for unobtrusive,real-time health monitoring,enhancing healthcare efficiency.However,their adoption is limited by performance ...Wearable electronic textiles(e-textiles)with embedded electronics offer promising solutions for unobtrusive,real-time health monitoring,enhancing healthcare efficiency.However,their adoption is limited by performance and sustainability challenges in materials,manufacturing,and recycling.This study introduces a sustainable paradigm for the fabrication of fully inkjet-printed Smart,Wearable,and Eco-friendly Electronic Textiles(SWEET)with the first comprehensive assessments of the biodegradability and life cycle assessment(LCA).SWEET addresses existing limitations,enabling concurrent and continuous monitoring of human physiology,including skin surface temperature(at temperature coefficient of resistance,TCR value of~-4.4%℃^(-1))and heart rate(-74 beats per minute,bpm)separately and simultaneously like the industry gold standard,using consistent,versatile,and highly efficient inkjet-printed graphene and Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)-based wearable e-textiles.Demonstrations with a wearable garment on five human participants confirm the system’s capability to monitor their electrocardiogram(ECG)signals and skin temperature.Such sustainable and biodegradable e-textiles decompose by-48%in weight and lost-98%strength over 4months.Life cycle assessment(LCA)reveals that the graphene-based electrode has the lowest climate change impact of-0.037 kg CO_(2) eq,40 times lower than reference electrodes.This approach addresses material and manufacturing challenges,while aligning with environmental responsibility,marking a significant leap forward in sustainable e-textile technology for personalized healthcare management.展开更多
One-dimensional(1D)metals are well known for their exceptional conductivity and their ease of formation of interconnected networks that facilitate electron migration,making them promising candidates for electromagneti...One-dimensional(1D)metals are well known for their exceptional conductivity and their ease of formation of interconnected networks that facilitate electron migration,making them promising candidates for electromagnetic(EM)attenuation.However,the impedance mismatch from high conductivity and their singular mode of energy loss hinder effective EM wave dissipation.Construction of cable structures not only optimizes impedance matching but also introduces a multitude of heterojunctions,increasing attenuation modes and potentially enhancing EM wave absorption(EMA)performance.Herein,we showcase the scalable synthesis of tin(Sn)whiskers from a Ti_(2)SnC MAX phase precursor,followed by creation of a 1D tin@carbon(Sn@C)cable structure through polymerization of PDA on their surface and annealing in argon.The EMA capabilities of Sn@C significantly surpass those of uncoated Sn whiskers,with an effective absorption bandwidth reaching 7.4 GHz.Remarkably,its maximum radar cross section reduction value of 27.85 dBm2 indicates its exceptional stealth capabilities.The enhanced EMA performance is first attributed to optimized impedance matching,and furthermore,the Sn@C cable structures have rich SnO2/C and Sn/SnO2 heterointerfaces and the associated defects,which increase interfacial and defect-induced polarization losses,as visually demonstrated by off-axis electron holography.The development of the Sn@C cable structure represents a notable advancement in broadening the scope of materials with potential applications in stealth technology,and this study also contributes to the understanding of how heterojunctions can improve EMA performance.展开更多
Weighted least-square support vector machine(WLS-SVM)is proposed in this research as a real-time transient stability evaluation method using the synchrophasor measurement received from phasor measurement units(PMUs).T...Weighted least-square support vector machine(WLS-SVM)is proposed in this research as a real-time transient stability evaluation method using the synchrophasor measurement received from phasor measurement units(PMUs).This method considers the directional overcurrent relays(DOCRs)for the transmission system,whereas in previous studies,the effect of protective mechanisms on the transient stability was largely ignored.When protective relays are activated in power system,the configuration of the power system is altered to mitigate the risk of the power system becoming unstable.The present study considers the operation of DOCRs in transmission lines for the transient stability so that the proposed method can respond to changes in the configuration of the case study system.In addition,WLS-SVM is employed for an online assessment of the transient stability.WLS-SVM not only is effective in response due to its faster speed,but also is resistant to noise and has excellent performance against the measurement errors of PMUs.To extract the characteristics of the vectors that are fed into the WLS-SVM algorithm,principal component analysis is used.The findings of the suggested technique reveal that it has higher accuracy and optimum performance,as compared to the extreme learning machine method,the adaptive neuro-fuzzy inference system method,and the back-propagation neural network method.The proposed technique is validated in the New England 39-bus system and the IEEE 118-bus system.展开更多
Bifacial photovoltaics (BPVs) are a promising alternative to conventional monofacial photovoltaics given their ability to exploit solar irradiance from both the front and rear sides of the panel, allowing for a higher...Bifacial photovoltaics (BPVs) are a promising alternative to conventional monofacial photovoltaics given their ability to exploit solar irradiance from both the front and rear sides of the panel, allowing for a higher amount of energy production per unit area. The BPV industry is still emerging, and there is much work to be done until it is a fully mature technology. There are a limited number of reviews of the BPV technology, and the reviews focus on different aspects of BPV. This review comprises an extensive in-depth look at BPV applications throughout all the current major applications, identifying studies conducted for each of the applications, and their outcomes, focusing on optimization for BPV systems under different applications, comparing levelized cost of electricity, integrating the use of BPV with existing systems such as green roofs, information on irradiance and electrical modeling, as well as providing future scope for research to improve the technology and help the industry.展开更多
Introduction:Forests form a major component of the carbon(C)reserves in the world’s ecosystems.However,little is known on how management influences C stocks of woody vegetation,particularly in dry areas.We developed ...Introduction:Forests form a major component of the carbon(C)reserves in the world’s ecosystems.However,little is known on how management influences C stocks of woody vegetation,particularly in dry areas.We developed regression models for two dominant tree species to predict C stocks and quantified the potential of community managed forests as C sinks.Methods:Plots were randomly selected from community-managed natural forest,herbivore exclosures,and from communal grazing land.Tree and shrub biomass were estimated using a regression model on the most dominant woody species while herbaceous biomass was determined using destructive sampling.Results:The simplest model,based on only one single predictor variable,showed a good fit to the data for both species(Juniperus procera and Acacia abyssinica).Diameter at breast height(r2>0.95)was a more reliable predictor than height(r2>0.54),crown diameter(r2>0.68)(p<0.001).The C content of the total biomass for the managed natural forest and the exclosure were estimated as,58.11 and 22.29 Mg ha−1,respectively,while that for the grazing land was 7.76 Mg ha−1,and the mean carbon content between the three land uses were significantly different(p<0.05).Conclusions:We conclude that forests managed by the community have a high potential for C sequestration and storage and their conservation should be promoted.展开更多
Multi-component occupancies of perovskite materials(ABO_(3))have brought diverse crystallographic distortions and highly tunable defect structures.These structural features enable ABO_(3)to have customizable dielectri...Multi-component occupancies of perovskite materials(ABO_(3))have brought diverse crystallographic distortions and highly tunable defect structures.These structural features enable ABO_(3)to have customizable dielectric and magnetic properties,offering new opportunities for advancing microwave absorbing materials.In this study,entropy-driven strategies,including composition optimization,structural/defective design,microstructure engineering,and microwave absorption simulation,are proposed to improve the microwave absorption capacity of(Ba_(1/3)Sr_(1/3)Ca_(1/3))FeO_(3).The hexagonal perovskite structure(Ba_(1/3)Sr_(1/3)Ca_(1/3))FeO_(3)prepared at 1100℃exhibits exceptional electromagnetic wave absorption properties,with a minimum reflection loss of−40.58 dB at a thickness of 1.2 mm and a maximum effective absorption bandwidth of 4.16 GHz.The results indicate that the interconnection of octahedra,and structural distortions,oxygen vacancies,and other defects enhance the dielectric polarization of the material,leading to excellent wave absorption performance.The entropy-driven design strategy for perovskite ABO_(3)materials offers valuable insights for the development of advanced electromagnetic wave absorption materials.展开更多
In the context of the fifth-generation(5G)smart era,the demand for electromagnetic wave(EMW)-absorbing materials has become increasingly prominent,so it is necessary to explore promising candidate materials.This work ...In the context of the fifth-generation(5G)smart era,the demand for electromagnetic wave(EMW)-absorbing materials has become increasingly prominent,so it is necessary to explore promising candidate materials.This work focuses on the exploration of the material absorbing properties of a MoAlB MAB(MAB represents a promising group of alternatives,where M stands for a transition metal,A typically denotes Al,and B is boron)phase system.First,the first-principles calculations were performed to reveal the unique crystal and layered structure of the MoAlB ceramics and to predict their potential for use as an EMW absorption material.Subsequently,a series of MoAlB ceramics were synthesized at temperatures ranging from 800 to 1300℃,and the influence of temperature on the phase compositions and microstructures of the obtained MoAlB ceramics was characterized and analyzed.Finally,the practical EMW absorption performance of the prepared MoAlB ceramics was evaluated via a combination of experiments and radar cross-sectional calculations.The MoAlB sample synthesized at 900℃ exhibits superior EMW absorption performance,achieving an impressive minimum reflection loss(RL)of−50.33 dB.The unique layered structure and good electrical conductivity of the MoAlB samples are the main reasons for their enhanced wave absorption performance,which provides interfacial polarization and multiple dielectric loss mechanisms.Therefore,this study not only contributes to the understanding of the preparation of MoAlB materials but also provides potential guidance for their utilization in the realm of electromagnetic wave absorption.展开更多
Accurately quantifying rates of soil erosion requires capturing both the volumetric nature of the visible,convergent fluvial pathways(also known as rills)and the subtle nature of the less-visible,diffuse pathways(inte...Accurately quantifying rates of soil erosion requires capturing both the volumetric nature of the visible,convergent fluvial pathways(also known as rills)and the subtle nature of the less-visible,diffuse pathways(interrill areas).The aim of this study was to use Rare Earth Oxide(REO)tracers and Structure-from-Motion(SfM)photogrammetry to elucidate retrospective information about soil erosion rates and sediment sources during different soil erosion conditions,within a controlled laboratory environment.The experimental conditions created erosion events consistent with diffuse and convergent erosion processes.REO tracers allowed the sediment transport distances of over 2 m to be described,and helped resolved the relative contribution of diffuse and convergent soil erosion;interrill areas were also iden-tified as a significant sediment sources soil loss under convergent erosion conditions.While the potential for SfM photogrammetry to resolve sub-millimetre elevations changes was demonstrated,under some conditions non-erosional changes in surface elevation,such as compaction,exceeded volumes of soil loss via diffuse erosion.The discrepancies between SfM Photogrammetry calculations and REO tagged sediment export were beneficial,identifying that during soil erosion events sediment in both aggregate and particle form is deposited within the convergent features,even when the rill extended the full length of the soil surface.The combination of SfM photogrammetry and REO tracers has provided a novel platform for building a spatial understanding of patterns of soil loss and source apportionment between rill and interrill erosion.展开更多
The rapid advancement of machine learning(ML)technology across diverse domains has provided a framework for discovering and rationalising materials and photovoltaic devices.This study introduces a five-step methodolog...The rapid advancement of machine learning(ML)technology across diverse domains has provided a framework for discovering and rationalising materials and photovoltaic devices.This study introduces a five-step methodology for implementing ML models in fabricating hole transport layer(HTL)free carbon-based PSCs(C-PSC).Our approach leverages various prevalentMLmodels,andwe curated a comprehensive dataset of 700 data points using SCAPS-1D simulation,encompassing variations in the thickness of the electron transport layer(ETL)and perovskite layers,along with bandgap characteristics.Our results indicate that the ANN-based ML model exhibits superior predictive accuracy for C-PSC device parameters,achieving a low root mean square error(RMSE)of 0.028 and a high R-squared value of 0.954.The novelty of this work lies in its systematic use ofMLto streamline the optimisation process,reducing the reliance on traditional trial-and-error methods and providing a deeper understanding of the interdependence of key device parameters.展开更多
Soil,a fundamental component of Earth’s ecosystems,plays a vital role in nutrient cycling,supports land productivity and food security,influences the water cycle[1],and sequesters carbon,with critical implications fo...Soil,a fundamental component of Earth’s ecosystems,plays a vital role in nutrient cycling,supports land productivity and food security,influences the water cycle[1],and sequesters carbon,with critical implications for climate regulation.Soil erosion affects the abovementioned ecosystem functions and has been widely acknowledged as one of the most severe global environmental threats[2].For instance,the latest report of the Food and Agriculture Organization of the United Nations indicates that soil erosion is projected to result in a 10%decline in global crop yields by 2050[3].Moreover,soil erosion transports large amounts of organic carbon into rivers and drives vertical greenhouse gas emissions during the mobilization of sediment[4,5].展开更多
基金supported by the National Natural Science Foundation of China(Nos.51708266,51968034,21667015,and 41807373)the National Key Research and Development Program of China(Nos.2018YFC0213400 and 2018YFC1900305)。
文摘To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liquid separation for copper slag slurry,the liquid-phase part has a critical influence on removing NO_(x)and SO_(2).Also,the leached metal ions played a crucial role in the absorption of SO_(2)and NO_(x).Subsequently,the effects of single/multi-metal ions on NO_(x)removal was investigated.The results showed that the leached metal from copper converter slag(Al^(3+),Cu^((2+),and Mg^((2+))and KMnO_(4)had a synergistic effect on NO_(x)removal,thereby improving the NO_(x)removal efficiency.Whereas Fe^(2+) had an inhibitory effect on the NO_(x)removal owing to the reaction between Fe^(2+) and KMnO_(4),thereby consuming the KMnO_(4).Besides,SO_(2)was converted to SO_(4)^(2-) completely partly due to the liquid catalytic oxidation by metal ions.The XRD and XPS results indicated that the Fe(Ⅱ)species(Fe_(2)SiO_(4),Fe_(3)O_(4))in copper slag can react with H+ions with the generation of Fe^(2+),and further consumed the KMnO_(4),thereby resulting in a decrease in the NO_(x)removal.The characterization of the slags and solutions before and after reaction led us to propose the possible mechanisms.The role of copper slag is as follows:(1)the alkaline substances in copper slag can absorb SO_(2)and NO_(2)by KMnO_(4)oxidation.(2)copper slag may function as a catalyst to accelerate SO_(2)conversion and improve NO_(x)removal by synergistic effect between leached metal ions and KMnO_(4).
基金supported by Natural Science Foundation of Yunnan Province(2009ZC027M)Innovation Fund of Science and Technology for Students(2012YA027)
文摘La0.9Sr0.1Ga0.8Mg0.2O3–？ （LSGM） electrolyte materials were synthesized by the solid state reaction method. The conductivity of LSGM materials was detected by four probe method, and it was 0.08 S/cm at 850 oC. Dense and uniform films of LSGM materials were deposited by the magnetic sputtering on substrates of Si and La0.7Sr0.3Cr0.5Mn0.5O3–？ （LSCM）. The experimental results showed that the deposition rates dropped and the average grain sizes of the films enlarged with increase in the substrate temperatures. In the sputtering process, the LSGM film was deposited with preferred growth direction. After annealing, the preferred growth direction disappeared and the film surface became smoother and denser. Through observing the deposition process, deposition mechanism was proposed, which was consistent with a model of island growth.
基金supported by the Annual Water and Fertilizer Efficient Utilization and Regulation Technology Research (2022YFD2300902-02)Key Cultivation Technology Innovation and Application of New Maize varieties (2021YFYZ0005)+1 种基金Soybean Maize Strip Mixed Cropping Planting Technology and Application in Tianfu New Area (XZY1-03)Soybean Green Increase Production and Efficiency Technology Integration and Demonstration in Meigu County (2022YFD1100203).
文摘Light is one of the most important environmental factors for plant growth and development.In relay cropping systems,crop layouts influence light distribution,affecting light use efficiency(LUE).However,the response of light interception,light conversion,and LUE for relay maize and relay soybean to different crop layouts remains unclear.We aimed to quantify the effect of crop layout on intraspecific and interspecific competition,light interception,light conversion,LUE,and land productivity between relay maize and relay soybean.We conducted a field experiment for four consecutive years from 2017 to 2020 in Sichuan province,China,comparing different crop layouts(bandwidth 2.0 m,row ratio 2:2;bandwidth 2.4 m,row ratio 2:3;bandwidth 2.8 m,row ratio 2:4),with sole maize and sole soybean as controls.The results showed that relay maize in the 2.0 m bandwidth layout had the largest leaf area index and plant biomass,the lowest intraspecific competitive intensity and the highest aggressiveness.Compared to a bandwidth of 2.0 m,a bandwidth of 2.8 m significantly decreased relay maize leaf area index by 11%and plant biomass by 24%,while a 2.4 m bandwidth caused roughly half these reductions.The 2.0 m bandwidth layout also significantly improved crop light interception and LUE compared to sole maize.The light interception,light interception rate,light conversion rate and LUE in relay maize all decreased significantly with increasing bandwidth,but they increased in relay soybean.The increased light transmittance to the lower and middle canopy with increasing bandwidth did not compensate for the loss of relay maize yield caused by increased intraspecific competition.However,it enhanced the yield of relay soybeans.Increasing the bandwidth by 80 cm increased the relay maize intraspecific competition by 580%,and reduced maize yield by 33%,light interception by 12%,and LUE by 18%.In contrast,the relay soybean intraspecific competition was reduced by 64%,and the soybean yield was increased by 26%,light interception by 32%and LUE by 46%.Relay cropping systems with a 2.0 m bandwidth optimize the trade-off between light transmittance and intraspecific competition of relay crops.These systems achieve the highest LUE,group yield and economic benefits,making them a recommended crop layout for the southwest regions of China.Our study offers valuable insights for developing strip relay cropping systems that maximize light utilization and contributes to the theoretical understanding of efficient sunlight use in relay cropping practices.
文摘Chitosan/coconut (CTS/coconut) composite membranes were successfully prepared by the cross-linking reaction with glutaraldehyde and they were applied in eliminating heavy metals from aqueous solutions. The cross-linked membranes were obtained at the ratios of 1/1, 1/1.5 and 1/2 and the coconut fiber was chemically treated by NaOCl/NaOH. The best ratio of CTS/coconut fiber is found to be 1/1.5 which has a relatively high stability with the degree of swelling (DS) and solvent content (SC) of membrane to be 13.33% and 69.88%, respectively. The results also indicate that the CTS membranes showed preferential separation of heavy metals for blend CTS/coconut membranes.
基金funding from Commonwealth Scholarship Commission(CSC)U.K.for a Ph.D.scholarship for Marzia DulalUKRI Research England the Expanding Excellence in England(E3)grant.
文摘Wearable electronic textiles(e-textiles)with embedded electronics offer promising solutions for unobtrusive,real-time health monitoring,enhancing healthcare efficiency.However,their adoption is limited by performance and sustainability challenges in materials,manufacturing,and recycling.This study introduces a sustainable paradigm for the fabrication of fully inkjet-printed Smart,Wearable,and Eco-friendly Electronic Textiles(SWEET)with the first comprehensive assessments of the biodegradability and life cycle assessment(LCA).SWEET addresses existing limitations,enabling concurrent and continuous monitoring of human physiology,including skin surface temperature(at temperature coefficient of resistance,TCR value of~-4.4%℃^(-1))and heart rate(-74 beats per minute,bpm)separately and simultaneously like the industry gold standard,using consistent,versatile,and highly efficient inkjet-printed graphene and Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)-based wearable e-textiles.Demonstrations with a wearable garment on five human participants confirm the system’s capability to monitor their electrocardiogram(ECG)signals and skin temperature.Such sustainable and biodegradable e-textiles decompose by-48%in weight and lost-98%strength over 4months.Life cycle assessment(LCA)reveals that the graphene-based electrode has the lowest climate change impact of-0.037 kg CO_(2) eq,40 times lower than reference electrodes.This approach addresses material and manufacturing challenges,while aligning with environmental responsibility,marking a significant leap forward in sustainable e-textile technology for personalized healthcare management.
基金National Natural Science Foundation of China,Grant/Award Numbers:52171033,52301263,U23A20574SEU Innovation Capability Enhancement Plan for Doctoral Students,Grant/Award Number:CXJH_SEU 24148。
文摘One-dimensional(1D)metals are well known for their exceptional conductivity and their ease of formation of interconnected networks that facilitate electron migration,making them promising candidates for electromagnetic(EM)attenuation.However,the impedance mismatch from high conductivity and their singular mode of energy loss hinder effective EM wave dissipation.Construction of cable structures not only optimizes impedance matching but also introduces a multitude of heterojunctions,increasing attenuation modes and potentially enhancing EM wave absorption(EMA)performance.Herein,we showcase the scalable synthesis of tin(Sn)whiskers from a Ti_(2)SnC MAX phase precursor,followed by creation of a 1D tin@carbon(Sn@C)cable structure through polymerization of PDA on their surface and annealing in argon.The EMA capabilities of Sn@C significantly surpass those of uncoated Sn whiskers,with an effective absorption bandwidth reaching 7.4 GHz.Remarkably,its maximum radar cross section reduction value of 27.85 dBm2 indicates its exceptional stealth capabilities.The enhanced EMA performance is first attributed to optimized impedance matching,and furthermore,the Sn@C cable structures have rich SnO2/C and Sn/SnO2 heterointerfaces and the associated defects,which increase interfacial and defect-induced polarization losses,as visually demonstrated by off-axis electron holography.The development of the Sn@C cable structure represents a notable advancement in broadening the scope of materials with potential applications in stealth technology,and this study also contributes to the understanding of how heterojunctions can improve EMA performance.
文摘Weighted least-square support vector machine(WLS-SVM)is proposed in this research as a real-time transient stability evaluation method using the synchrophasor measurement received from phasor measurement units(PMUs).This method considers the directional overcurrent relays(DOCRs)for the transmission system,whereas in previous studies,the effect of protective mechanisms on the transient stability was largely ignored.When protective relays are activated in power system,the configuration of the power system is altered to mitigate the risk of the power system becoming unstable.The present study considers the operation of DOCRs in transmission lines for the transient stability so that the proposed method can respond to changes in the configuration of the case study system.In addition,WLS-SVM is employed for an online assessment of the transient stability.WLS-SVM not only is effective in response due to its faster speed,but also is resistant to noise and has excellent performance against the measurement errors of PMUs.To extract the characteristics of the vectors that are fed into the WLS-SVM algorithm,principal component analysis is used.The findings of the suggested technique reveal that it has higher accuracy and optimum performance,as compared to the extreme learning machine method,the adaptive neuro-fuzzy inference system method,and the back-propagation neural network method.The proposed technique is validated in the New England 39-bus system and the IEEE 118-bus system.
文摘Bifacial photovoltaics (BPVs) are a promising alternative to conventional monofacial photovoltaics given their ability to exploit solar irradiance from both the front and rear sides of the panel, allowing for a higher amount of energy production per unit area. The BPV industry is still emerging, and there is much work to be done until it is a fully mature technology. There are a limited number of reviews of the BPV technology, and the reviews focus on different aspects of BPV. This review comprises an extensive in-depth look at BPV applications throughout all the current major applications, identifying studies conducted for each of the applications, and their outcomes, focusing on optimization for BPV systems under different applications, comparing levelized cost of electricity, integrating the use of BPV with existing systems such as green roofs, information on irradiance and electrical modeling, as well as providing future scope for research to improve the technology and help the industry.
文摘Introduction:Forests form a major component of the carbon(C)reserves in the world’s ecosystems.However,little is known on how management influences C stocks of woody vegetation,particularly in dry areas.We developed regression models for two dominant tree species to predict C stocks and quantified the potential of community managed forests as C sinks.Methods:Plots were randomly selected from community-managed natural forest,herbivore exclosures,and from communal grazing land.Tree and shrub biomass were estimated using a regression model on the most dominant woody species while herbaceous biomass was determined using destructive sampling.Results:The simplest model,based on only one single predictor variable,showed a good fit to the data for both species(Juniperus procera and Acacia abyssinica).Diameter at breast height(r2>0.95)was a more reliable predictor than height(r2>0.54),crown diameter(r2>0.68)(p<0.001).The C content of the total biomass for the managed natural forest and the exclosure were estimated as,58.11 and 22.29 Mg ha−1,respectively,while that for the grazing land was 7.76 Mg ha−1,and the mean carbon content between the three land uses were significantly different(p<0.05).Conclusions:We conclude that forests managed by the community have a high potential for C sequestration and storage and their conservation should be promoted.
基金supported by the Natural Science Foundation Outstanding Youth Fund Project of Henan Province(No.242300421009)the Henan Provincial Science and Technology Research Project(Nos.241111232800 and 232102230115)+1 种基金the Joint Fund of Research and Development Program of Henan Province(No.222301420002)the National Natural Science Foundation of China(No.U21A2064).
文摘Multi-component occupancies of perovskite materials(ABO_(3))have brought diverse crystallographic distortions and highly tunable defect structures.These structural features enable ABO_(3)to have customizable dielectric and magnetic properties,offering new opportunities for advancing microwave absorbing materials.In this study,entropy-driven strategies,including composition optimization,structural/defective design,microstructure engineering,and microwave absorption simulation,are proposed to improve the microwave absorption capacity of(Ba_(1/3)Sr_(1/3)Ca_(1/3))FeO_(3).The hexagonal perovskite structure(Ba_(1/3)Sr_(1/3)Ca_(1/3))FeO_(3)prepared at 1100℃exhibits exceptional electromagnetic wave absorption properties,with a minimum reflection loss of−40.58 dB at a thickness of 1.2 mm and a maximum effective absorption bandwidth of 4.16 GHz.The results indicate that the interconnection of octahedra,and structural distortions,oxygen vacancies,and other defects enhance the dielectric polarization of the material,leading to excellent wave absorption performance.The entropy-driven design strategy for perovskite ABO_(3)materials offers valuable insights for the development of advanced electromagnetic wave absorption materials.
基金the Joint Fund of R&D Program of Henan Province(No.222301420002)the Outstanding Youth Fund of Henan Province(No.242300421009)+3 种基金the National Natural Science Foundation of China(No.U21A2064)the Scientific and Technological Innovation Talents in Colleges and Universities in Henan Province(No.22HASTIT001)the Henan Province Key Research Project for Higher Education Institutions(No.23B430017)Bingbing Fan thanks the China Scholarship Council(CSC,No.202207045028)for an academic visitor scholarship,and Wei Li is grateful for the financial support from the Technical University of Darmstadt.
文摘In the context of the fifth-generation(5G)smart era,the demand for electromagnetic wave(EMW)-absorbing materials has become increasingly prominent,so it is necessary to explore promising candidate materials.This work focuses on the exploration of the material absorbing properties of a MoAlB MAB(MAB represents a promising group of alternatives,where M stands for a transition metal,A typically denotes Al,and B is boron)phase system.First,the first-principles calculations were performed to reveal the unique crystal and layered structure of the MoAlB ceramics and to predict their potential for use as an EMW absorption material.Subsequently,a series of MoAlB ceramics were synthesized at temperatures ranging from 800 to 1300℃,and the influence of temperature on the phase compositions and microstructures of the obtained MoAlB ceramics was characterized and analyzed.Finally,the practical EMW absorption performance of the prepared MoAlB ceramics was evaluated via a combination of experiments and radar cross-sectional calculations.The MoAlB sample synthesized at 900℃ exhibits superior EMW absorption performance,achieving an impressive minimum reflection loss(RL)of−50.33 dB.The unique layered structure and good electrical conductivity of the MoAlB samples are the main reasons for their enhanced wave absorption performance,which provides interfacial polarization and multiple dielectric loss mechanisms.Therefore,this study not only contributes to the understanding of the preparation of MoAlB materials but also provides potential guidance for their utilization in the realm of electromagnetic wave absorption.
文摘Accurately quantifying rates of soil erosion requires capturing both the volumetric nature of the visible,convergent fluvial pathways(also known as rills)and the subtle nature of the less-visible,diffuse pathways(interrill areas).The aim of this study was to use Rare Earth Oxide(REO)tracers and Structure-from-Motion(SfM)photogrammetry to elucidate retrospective information about soil erosion rates and sediment sources during different soil erosion conditions,within a controlled laboratory environment.The experimental conditions created erosion events consistent with diffuse and convergent erosion processes.REO tracers allowed the sediment transport distances of over 2 m to be described,and helped resolved the relative contribution of diffuse and convergent soil erosion;interrill areas were also iden-tified as a significant sediment sources soil loss under convergent erosion conditions.While the potential for SfM photogrammetry to resolve sub-millimetre elevations changes was demonstrated,under some conditions non-erosional changes in surface elevation,such as compaction,exceeded volumes of soil loss via diffuse erosion.The discrepancies between SfM Photogrammetry calculations and REO tagged sediment export were beneficial,identifying that during soil erosion events sediment in both aggregate and particle form is deposited within the convergent features,even when the rill extended the full length of the soil surface.The combination of SfM photogrammetry and REO tracers has provided a novel platform for building a spatial understanding of patterns of soil loss and source apportionment between rill and interrill erosion.
基金funded by the Engineering and Physical Sciences Research Council,UK:PhD Fellowship and Engineering and Physical Sciences Research Council,UK:EP/T025875/1.
文摘The rapid advancement of machine learning(ML)technology across diverse domains has provided a framework for discovering and rationalising materials and photovoltaic devices.This study introduces a five-step methodology for implementing ML models in fabricating hole transport layer(HTL)free carbon-based PSCs(C-PSC).Our approach leverages various prevalentMLmodels,andwe curated a comprehensive dataset of 700 data points using SCAPS-1D simulation,encompassing variations in the thickness of the electron transport layer(ETL)and perovskite layers,along with bandgap characteristics.Our results indicate that the ANN-based ML model exhibits superior predictive accuracy for C-PSC device parameters,achieving a low root mean square error(RMSE)of 0.028 and a high R-squared value of 0.954.The novelty of this work lies in its systematic use ofMLto streamline the optimisation process,reducing the reliance on traditional trial-and-error methods and providing a deeper understanding of the interdependence of key device parameters.
基金supported by the National Natural Science Foundation of China(52479055)the National Key R&D Program of China(2023YFC3209900)the Excellent Young Scientists Fund of the National Natural Science Foundation of China.
文摘Soil,a fundamental component of Earth’s ecosystems,plays a vital role in nutrient cycling,supports land productivity and food security,influences the water cycle[1],and sequesters carbon,with critical implications for climate regulation.Soil erosion affects the abovementioned ecosystem functions and has been widely acknowledged as one of the most severe global environmental threats[2].For instance,the latest report of the Food and Agriculture Organization of the United Nations indicates that soil erosion is projected to result in a 10%decline in global crop yields by 2050[3].Moreover,soil erosion transports large amounts of organic carbon into rivers and drives vertical greenhouse gas emissions during the mobilization of sediment[4,5].
