As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-int...As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-interaction benefits and clear business models.Consequently,assessing the value of grid-alternative energy storage in the systemtransition has become critically important.Considering the performance characteristics of storage,we propose a value assessment frame-work for grid-alternative energy storage,quantifying its non-wires-alternative effects from both cost and benefit perspectives.Building on this,we developed a collaborative planning model for energy storage and transmission grids,aimed at maximizing the economic benefits of storage systems while balancing investment and operational costs.The model considers regional grid interconnections and their interactions with system operation.By participating in system operations,grid-alternative energy storage not only maximizes its own economic benefits but also generates social welfare transfer effects.Furthermore,based on multi-regional interconnected planning,grid-alternative energy storage can reduce system costs by approximately 35%,with the most significant changes observed in generation costs.Multi-regional coordinated planning significantly enhances the sys-tem’s flexibility in regulation.However,when the load factor of interconnection lines between regions remains constant,system operational flexibility tends to decrease,leading to a roughly 28.9%increase in storage investment.Additionally,under regional coordinated planning,the greater the disparity in wind power integration across interconnected regions,the more noticeable the reduction in system costs.展开更多
Redox-active organic compounds have received much attention as high-capacity electrodes for rechargeable batteries.However,the high solubility in organic electrolytes during charge and discharge processes hinders the ...Redox-active organic compounds have received much attention as high-capacity electrodes for rechargeable batteries.However,the high solubility in organic electrolytes during charge and discharge processes hinders the practical exploitation of organic compounds.This study presents a cobalt-based metal–organic coordination compound with bifunctional coordinated water(Co-MOC-H_(2)O)for sodium-ion storage.The coordinated water enhances interactions between sodium ions and nitrogen atoms in organic ligands through chelation,activating the inert sodium-ion storage sites(C=N).Moreover,the stable hydrogen bonded framework formed by the coordinated water molecules prevents the active organic compounds from dissolving into the electrolyte,thereby enhancing cycling stability.With the bifunctional coordinated water molecules,the Co-MOC-H_(2)O electrode delivers a high capacity of 403 mAh g^(-1)at 0.2 A g^(-1)over 600 cycles and exhibits a capacity retention of 77.9%at 2 A g^(-1)after 1100 cycles.This work highlights the crucial role of the coordinated water molecules in constructing high capacity and long-life sodium-ion storage materials.展开更多
The coordinated regional development strategy,recognized as one of China’s seven development strategies,plays a crucial role in reducing regional development disparities,optimizing resource allocation,and facilitatin...The coordinated regional development strategy,recognized as one of China’s seven development strategies,plays a crucial role in reducing regional development disparities,optimizing resource allocation,and facilitating high-quality development.This study analyzes a total of 418 relevant publications from China spanning the years 1998 to 2022.Utilizing CiteSpace software,a visualization analysis of keyword cooccurrence,mutation,and other bibliometric characteristics was conducted.The findings indicate that the number of publications during the specified period exhibited a fluctuating upward trend,with a notable increase observed after 2018.Furthermore,the research demonstrated a weak interdisciplinary crossover and a low intensity of collaboration among authors.The primary thematic areas of focus were identified as follows:connotation,mechanisms,countermeasure and suggestion,and evaluation.展开更多
Conventional coordinated control strategies for DC bus voltage signal(DBS)in islanded DC microgrids(IDCMGs)struggle with coordinating multiple distributed generators(DGs)and cannot effectively incorporate state of cha...Conventional coordinated control strategies for DC bus voltage signal(DBS)in islanded DC microgrids(IDCMGs)struggle with coordinating multiple distributed generators(DGs)and cannot effectively incorporate state of charge(SOC)information of the energy storage system,thereby reducing the system flexibility.In this study,we propose an adaptive coordinated control strategy that employs a two-layer fuzzy neural network controller(FNNC)to adapt to varying operating conditions in an IDCMG with multiple PV and battery energy storage system(BESS)units.The first-layer FNNC generates optimal operating mode commands for each DG,thereby avoiding the requirement for complex operating modes based on SOC segmentation.An optimal switching sequence logic prioritizes the most appropriate units during mode transitions.The second-layer FNNC dynamically adjusts the droop power to overcome power distribution challenges among DG groups.This helps in preventing the PV power from exceeding the limits and mitigating the risk of BESS overcharging or over-discharging.The simulation results indicate that the proposed strategy enhances the coordinated operation of multi-DG IDCMGs,thereby ensuring the efficient and safe utilization of PV and BESS.展开更多
The disorganized lithium dendrites and unstable solid electrolyte interphase(SEI)severely impede the practical application of lithium metal batteries(LMBs).Herein,the N-Zn-F coordinated triazine-based covalent organic...The disorganized lithium dendrites and unstable solid electrolyte interphase(SEI)severely impede the practical application of lithium metal batteries(LMBs).Herein,the N-Zn-F coordinated triazine-based covalent organic framework(TTA-COF-ZnF_(2))is fabricated for the first time as an artificial SEI layer on the surface of lithium metal anodes(LMAs)to handle these issues.Zn-N coordination in onedimensional(1D)ordered COF can increase lithiophilic sites,reduce the Li-nucleation barrier,and regulate the Li+local coordination environment by optimizing surface charge density around the Zn metal.The electron-rich state induced by strong electron-withdrawing F-groups constructs electronegative nanochannels,which trigger efficient Li+desolvation.These beneficial attributes boost Li^(+)transfer,and homogenize Li^(+)flux,leading to uniform Li deposition.Besides,the lithiophilic triazine ring polar groups in TTA-COF-ZnF_(2)further facilitate the Li^(+)migration.The latent working mechanism of adjusting Li deposition behaviors and stabilizing LMAs for TTA-COF-ZnF_(2)is illustrated by detailed in-situ/ex-situ characterizations and density functional theory(DFT)calculations.As expected,TTA-COF-ZnF_(2)-modified Li|Cu half cells deliver a higher Coulombic efficiency(CE)of 98.4% over 250 cycles and lower nucleation overpotential(11 mV)at 1 mA cm^(-2),while TTA-COF-ZnF_(2)@Li symmetric cells display a long lifespan over3785 h at 2 mA cm^(-2).The TTA-COF-ZnF_(2)@Li|S full cells exert ultra high capacity retention of 81%(837 mA h g^(-1))after 600 cycles at 1C.Besides,the TTA-COF-ZnF_(2)@Li|LFP full cells with a high loading of 7.1 mg cm^(-2)exert ultrahigh capacity retention of 89%(108 mAh g^(-1))after 700 cycles at 5C.This synergistic strategy in N-Zn-F coordinated triazine-based COF provides a new insight to regulate the uniform platins/stripping behaviors for developing ultra-stable and dendrite-free LMBs.展开更多
Agricultural insurance plays a key role in promoting the coordinated development of green agriculture and farmers’income growth,which is crucial for China’s high-quality agricultural development.Using the coupling c...Agricultural insurance plays a key role in promoting the coordinated development of green agriculture and farmers’income growth,which is crucial for China’s high-quality agricultural development.Using the coupling coordination degree model,this study empirically demonstrates that the development of agricultural insurance significantly promotes the coordinated development of green agriculture and farmers’income growth once a certain threshold is exceeded.This effect is more pronounced in the major grain-producing regions and the central provinces.Expanding the scale of agricultural production and increasing investment in agricultural technology are the key mechanisms through which agricultural insurance supports the dual goals of green agriculture and income growth in China.In conclusion,this study proposes several policy recommendations,which include increasing investment in agricultural insurance infrastructure,strengthening the policy guidance for agricultural insurance,and designing differentiated agricultural insurance policies.展开更多
This paper concerns the exponential attitude-orbit coordinated control problems for gravitational-wave detection formation spacecraft systems.Notably,the large-scale communication delays resulting from oversized inter...This paper concerns the exponential attitude-orbit coordinated control problems for gravitational-wave detection formation spacecraft systems.Notably,the large-scale communication delays resulting from oversized inter-satellite distance of space-based laser interferometers are first modeled.Subject to the delayed communication behaviors,a new delay-dependent attitude-orbit coordinated controller is designed.Moreover,by reconstructing the less conservative Lyapunov-Krasovskii functional and free-weight matrices,sufficient criteria are derived to ensure the exponential stability of the closed-loop relative translation and attitude error system.Finally,a simulation example is employed to illustrate the numerical validity of the proposed controller for in-orbit detection missions.展开更多
The exploration of the coupling and coordination between urban innovation capability(IC)and industrial transformation(IF)serves as a novel perspective for interpreting the increasingly severe phenomenon of population ...The exploration of the coupling and coordination between urban innovation capability(IC)and industrial transformation(IF)serves as a novel perspective for interpreting the increasingly severe phenomenon of population shrinkage during the industrialization process.This study investigated the evolutionary characteristics of IC and IF in shrinking and growing cities in Northeast China from 2010 to 2020.It uses entropy weighted model,coupling coordination degree,the Dagum Gini coefficient,and geographic detectors to analyze the coordinated development of IC and IF in the context of population shrinkage.The study analyzed the spatiotemporal patterns and driving mechanisms for their coordinated development.The results show that:1)both urban IC and IF exhibited an overall positive trend during the study period.Shrinking cities depend more on IF to address the challenges of population shrinkage,while growing cities mainly rely on innovation-driven development.2)The coupling gap between IC and IF in shrinking and growing cities has widened over time,with the coordination level of shrinking cities steadily decreasing.Cities with serious disorder are concentrated in northern Heilongjiang Province,while most cities in Jilin Province experience moderate disorder.Liaoning Province,however,shows generally good coupling coordination.3)Human capital is the key factor driving coupling coordination in both types of cities.Shrinking cities rely on economic and financial development,with the‘repair-type’logic that emphasizes short-term economic growth and resource compensation.In contrast,the coupling of growing cities relies on basic support capabilities,with the‘optimization-type’logic focused on enhancing endogenous resilience and systemic coordination.Exploring the coordination between urban innovation capabilities and industrial transformation can provide a new perspective for research on population shrinkage,which holds certain theoretical and practical significance for implementing the new round of revitalization strategy in Northeast China.展开更多
During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To ad...During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To address this issue,the rear landing gear is typically designed to steer in coordination with the nose wheels,reducing sideslip and improving maneuverability.This study examines how structural parameters and weight distribution affect the performance of coordinated steering in landing gear design for large transport aircraft.Using the C-5 transport aircraft as a case study,we develop a multi-wheel ground steering dynamics model,incorporating the main landing gear(MLG)deflection.A ground handling dynamics model is also established to evaluate the benefits of coordinated steering for rear MLG during steering.Additionally,the study analyzes the impact of structural parameters such as stiffness and damping on the steering performance of the C-5.It further investigates the effects of weight distribution,including the center-of-gravity(CG)height,the longitudinal CG position,and the mass asymmetry.Results show that when the C-5 employs coordinated steering for rear MLG,the lateral friction coefficients of the NLG tires decrease by 22%,24%,26%,and 27%.The steering radius is reduced by 29.7%,and the NLG steering moment decreases by 19%,significantly enhancing maneuverability.Therefore,in the design of landing gear for large transport aircraft,coordinated MLG steering,along with optimal structural and CG position parameters,should be primary design objectives.These results provide theoretical guidance for the design of multi-wheel landing gear systems in large transport aircraft.展开更多
Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4...Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4WIS)vehicles,the steering systems of the four wheels are relatively independent,and there are differences and uncertainties in individual steering dynamics,which lead to challenges for all four wheels in simultaneously satisfying the ASP and may deteriorate the vehicle path tracking performance.In response to this problem,this paper introduces a four-wheel consistent coordinated steering control for 4WIS vehicles.The algorithm innovatively reconfigures the Ackerman steering relationships as coupling constraints among the wheels,and utilizes the constraint-following method to design controller.The controller achieves uniform boundedness(UB)and uniform ultimate boundedness(UUB)of ASP constraint error.The Carsim/Simulink joint simulation results demonstrate that the algorithm guarantees the approximate satisfaction of ASP in both the transient and steady-state of the vehicle path tracking.Also,it significantly improves the path tracking performance.展开更多
Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional th...Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional theory(DFT)calculations,we systematically investigate the catalytic activity of iron-nitrogen-carbon based covalent organic frameworks(COF)monolayers with axially coordinated ligands(denotes as Fe N_(4)-X@COF,X refers to axial ligand,X=-SCN,-I,-H,-SH,-NO_(2),-Br,-ClO,-Cl,-HCO_(3),-NO,-ClO_(2),-OH,-CN and-F).The calculated results demonstrate that all the catalysts possess good thermodynamic and electrochemical stabilities.The different ligands axially ligated to the Fe active center could induce changes in the charge of the Fe center,which further regulates the interaction strength between intermediates and catalysts that governs the catalytic activity.Importantly,FeN_(4)-SH@COF and Fe N_(4)-OH@COF are efficient bifunctional catalysts for HER and OER,FeN_(4)-OH@COF and FeN_(4)-I@COF are promising bifunctional catalysts for OER and ORR.These findings not only reveal promising bifunctional HER/OER and OER/ORR catalysts but also provide theoretical guidance for designing optimum ironnitrogen-carbon based catalysts.展开更多
A group optimal penetration strategy in complex attack and defense confrontation situation is proposed in this paper to solve the coordinated penetration decision-making problem of endo-atmospheric gliding simultaneou...A group optimal penetration strategy in complex attack and defense confrontation situation is proposed in this paper to solve the coordinated penetration decision-making problem of endo-atmospheric gliding simultaneous multi-missile penetration of interceptors.First,the problem of large search space of multi-missile coordinated penetration maneuvers is fully considered,and the flight corridor of multi-missile coordinated penetration is designed to constrain search space of multi-agent coordinated strategy,comprehensively considering path constraints and anticollision constraints of gliding multi-missile flight.Then,a multi-missile hierarchical coordinated decision-making mechanism based on confrontation situation is proposed,and the swarm penetration strategy is optimized with the goal of maximizing swarm penetration effectiveness.The upper layer plans the swarm penetration formation according to confrontation situation,and generates the swarm coordinated penetration trajectory based on Multi-Agent Deep Deterministic Policy Gradient(MADDPG)method.The lower layer interpolates and smooths penetration trajectory,and generates the penetration guidance command based on Soft Actor-Critic and Extended Proportional Guidance(SAC-EPG)method.Simulation results verify that the proposed multi-missile cooperative penetration method based on hierarchical reinforcement learning converges faster than the penetration method based on MADDPG,and can quickly learn multi-missile cooperative penetration skills.In addition,multi-missile coordination can give full play to the group's detection and maneuverability,and occupy favorable penetration time and space through coordinated ballistic maneuvers.Thus the success rate of group penetration can be improved.展开更多
Four-electron oxygen evolving reaction is limited by proton adsorption and desorption,making its reaction kinetics sluggish,which poses a major challenge for catalyst design.Here,we present an unsaturated coordination...Four-electron oxygen evolving reaction is limited by proton adsorption and desorption,making its reaction kinetics sluggish,which poses a major challenge for catalyst design.Here,we present an unsaturated coordination interface by constructing a fast electron transfer channel between Cu_(2)V_(2)O_(7)(CVO)and BiVO4(BVO).X-ray absorption spectroscopy(XAS)and theoretical calculations results confirm that CVO and BVO between interfaces are bonded by the way of unsaturated coordination oxygen(Ouc).The Ouc optimizes the O-O coupled energy barrier at the V active site and promotes the disconnection of O-H bond,which increases the photocurrent intensity of CVO by 6 times.In addition,due to the high electronegativity of the Ouc,the bonding energies of Bi-O and Cu-O at the interface are enhanced,resulting in the long-term stability of the photoanode during the water splitting.Finally,by integrating the working electrode with a polysilicon solar cell,we assembled a device that demonstrated exceptional catalytic performance,achieving a hydrogen production rate of 100.6μmol·cm^(-2),and maintaining a hydrogen-to-oxygen volume ratio of 2:1 after continuous operation for 4 h.This discovery aids in a deeper understanding of photoanode design and offers further insights for industrial applications.展开更多
In this paper,a distributed Event-Triggered(ET)collision avoidance coordinated control for Quadrotor Unmanned Aerial Vehicles(QUAVs)is proposed based on Virtual Tubes(VTs)with flexible boundaries in the presence of un...In this paper,a distributed Event-Triggered(ET)collision avoidance coordinated control for Quadrotor Unmanned Aerial Vehicles(QUAVs)is proposed based on Virtual Tubes(VTs)with flexible boundaries in the presence of unknown external disturbances.Firstly,VTs are constructed for each QUAV,and the QUAV is restricted into the corresponding VT by the artificial potential field,which is distributed around the boundary of the VT.Thus,the collisions between QUAVs are avoided.Besides,the boundaries of the VTs are flexible by the modification signals,which are generated by the self-regulating auxiliary systems,to make the repulsive force smaller and give more buffer space for QUAVs without collision.Then,a novel ET mechanism is designed by introducing the concept of prediction to the traditional fixed threshold ET mechanism.Furthermore,a disturbance observer is proposed to deal with the adverse effects of the unknown external disturbance.On this basis,a distributed ET collision avoidance coordinated controller is proposed.Then,the proposed controller is quantized by the hysteresis uniform quantizer and then sent to the actuator only at the ET instants.The boundedness of the closed-loop signals is verified by the Lyapunov method.Finally,simulation and experimental results are performed to demonstrate the superiority of the proposed control method.展开更多
Ports,the core hub of global supply chains,serve as vital links in the economic and trade exchanges among countries.Efficient,safe,green and smart ports are essential for the smooth operation of global trade.Recently,...Ports,the core hub of global supply chains,serve as vital links in the economic and trade exchanges among countries.Efficient,safe,green and smart ports are essential for the smooth operation of global trade.Recently,ISO established ISO/TC 8/SC 27,Ports and terminals,the secretariat of which is held by China.This is a big breakthrough of China’s participation in the international standardization activities in the area of transportation.展开更多
A tumor cell membrane(CM)-based biomimetic membrane tumor vaccine is an emerging prevention and treatment strategy in tumor immunotherapy.However,a single CM mostly has a weak immune-boosting effect.Here,a heterogenic...A tumor cell membrane(CM)-based biomimetic membrane tumor vaccine is an emerging prevention and treatment strategy in tumor immunotherapy.However,a single CM mostly has a weak immune-boosting effect.Here,a heterogenic fusion membrane tumor vaccine,EV–CM,was successfully constructed by fusing extracellular vesicles(EVs)from S.aureus and CM from B16F10 melanoma cells.Inheriting the advantages of parental components,the EV–CM combines tumor antigens with natural adjuvants that can be used for immunotherapy and can be easily synergistic with complementary therapies.In vivo vaccine tests have shown that EV–CM can activate immune antitumor responses and prevent tumorigenesis.To further enhance the immunotherapeutic and antimetastatic effects of EV–CM,Pt-porphyrin coordination polymer as an immunopotentiator(CPIP)was implanted into an EV–CM nanoplatform(CPIP@EV–CM),which combines localized sonodynamic/chemodynamic therapy-induced immunogenic cell death with heterogenic fusion membrane-mediated antigen-presenting functions.In vitro performance tests,cell experiments,and in vivo animal models have confirmed that the CPIP@EV–CM combined with US has better ROS production,tumor cell killing,and antimetastasis abilities.The heterogenic fusion membrane strategy and ultrasound-augmented nanoplatform present exciting prospects for designing tumor-immunogenic,self-adjuvant,and expandable vaccines,providing new ideas for exploring new melanoma immunotherapy and antimetastasis strategies,which is expected to be used as a safe and effective treatment in clinical practice.展开更多
The coordinated control of PM_(2.5)and ozone has become the strategic goal of national air pollution control.Considering the gradual decline in PM_(2.5)concentration and the aggravation of ozone pollution,a better und...The coordinated control of PM_(2.5)and ozone has become the strategic goal of national air pollution control.Considering the gradual decline in PM_(2.5)concentration and the aggravation of ozone pollution,a better understanding of the coordinated control of PM_(2.5)and ozone is urgently needed.Here,we collected and sorted air pollutant data for 337 cities from 2015 to 2020 to explore the characteristics of PM_(2.5)and ozone pollution based on China’s five major air pollution regions.The results show that it is necessary to continue to strengthen the emission reduction in PM_(2.5)and ozone precursors,and control NO_(x) and VOCs while promoting a dramatic emission reduction in PM_(2.5).The primary method of curbing ozone pollution is to strengthen the emission control of VOCs,with a long-term strategy of achieving substantial emission reductions in NO_(x),because VOCs and NO_(x) are also precursors to PM_(2.5);hence,their reductions also contribute to the reduction in PM_(2.5).Therefore,the implementation of a multipollutant emission reduction control strategy aimed at the prevention and control of PM_(2.5)and ozone pollution is the only means to realize the coordinated control of PM_(2.5)and ozone.展开更多
Comprehensive analysis of the Economy-Energy-Carbon Emission(EECE)system is beneficial for promoting sustainable social development.This study analyzes the system development of major watersheds in China from 2010 to ...Comprehensive analysis of the Economy-Energy-Carbon Emission(EECE)system is beneficial for promoting sustainable social development.This study analyzes the system development of major watersheds in China from 2010 to 2019.The research fully considers the system’s internal and external inputs and outputs and proposes an evaluation index system for regional EECE coupling and coordinated development.Then,using the difference in system weight allocation to improve the coupling and coordination model,the study explores the dynamic system’s coupling and coordination.The results show that(1)The development of the system structure is relatively stable,but the overall development status is not ideal;(2)The downstream of China’s main river basins has obvious economic advantages,while the energy system fluctuates greatly.The efficiency of the carbon emission system will decrease in areas with rapid economic development.The coupling and coordination level of the EECE system is better in the Yangtze River Basin than in the Yellow River Basin;(3)From the perspective of dynamic coordinated development,the main river basins have been divided into two states since 2012,but it is relatively stable overall.Regional dynamic coordination is often at a disadvantage in regions with rapid economic and energy development;(4)The coupling coordination degree of the two river basins has significant positive spatial autocorrelation.Most provinces’significant spatial clustering characteristics of the coupling coordination degree are High-High type.Low-Low type provinces are mainly concentrated downstream.The research process has certain reference significance for the collaborative governance of complex regional systems.展开更多
Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites...Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.展开更多
In this study,the interplay between ecosystem services and human well-being in Seni district,which is a pastoral region of Nagqu city on the Qinghai-Tibet Plateau,is investigated.Employing the improved InVEST model,CA...In this study,the interplay between ecosystem services and human well-being in Seni district,which is a pastoral region of Nagqu city on the Qinghai-Tibet Plateau,is investigated.Employing the improved InVEST model,CASA model,coupling coordination model,and hierarchical clustering method,we analyze the spatiotemporal patterns of ecosystem services,the levels of resident well-being levels,and the interrelationships between these factors over the period from 2000 to 2018.Our findings reveal significant changes in six ecosystem services,with water production decreasing by 7.1%and carbon sequestration and soil conservation services increasing by approximately 6.3%and 14.6%,respectively.Both the habitat quality and landscape recreation services remained stable.Spatially,the towns in the eastern and southern areas exhibited higher water production and soil conservation services,while those in the central area exhibited greater carbon sequestration services.The coupling and coordination relationship between ecosystem services and human well-being improved significantly over the study period,evolving from low-level coupling to coordinated coupling.Hierarchical clustering was used to classify the 12 town-level units into five categories.Low subjective well-being townships had lower livestock breeding services,while high subjective well-being townships had higher supply,regulation,and support ecosystem services.Good transportation conditions were associated with higher subjective well-being in townships with low supply services.We recommend addressing the identified transportation disparities and enhancing key regulatory and livestock breeding services to promote regional sustainability and improve the quality of life for Seni district residents,thus catering to the diverse needs of both herdsmen and citizens.展开更多
基金funded by the Technology Project of State Grid Jibei Electric Power Supply Co.,Ltd.(Grant Number:52018F240001).
文摘As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-interaction benefits and clear business models.Consequently,assessing the value of grid-alternative energy storage in the systemtransition has become critically important.Considering the performance characteristics of storage,we propose a value assessment frame-work for grid-alternative energy storage,quantifying its non-wires-alternative effects from both cost and benefit perspectives.Building on this,we developed a collaborative planning model for energy storage and transmission grids,aimed at maximizing the economic benefits of storage systems while balancing investment and operational costs.The model considers regional grid interconnections and their interactions with system operation.By participating in system operations,grid-alternative energy storage not only maximizes its own economic benefits but also generates social welfare transfer effects.Furthermore,based on multi-regional interconnected planning,grid-alternative energy storage can reduce system costs by approximately 35%,with the most significant changes observed in generation costs.Multi-regional coordinated planning significantly enhances the sys-tem’s flexibility in regulation.However,when the load factor of interconnection lines between regions remains constant,system operational flexibility tends to decrease,leading to a roughly 28.9%increase in storage investment.Additionally,under regional coordinated planning,the greater the disparity in wind power integration across interconnected regions,the more noticeable the reduction in system costs.
基金supported by the National Natural Science Foundation of China(22121005,92372203,92372001,52072186,and 52301278)the National Key Research and Development Program of China(2022YFB2402200)+3 种基金the Science and Technology Plans of Tianjin(23JCYBJC00170)the Fundamental Research Funds for the Central Universities,Nankai University(63241206 and 9242000710)Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering(JDSX2023003)the Natural Science Foundation of Jiangsu Province(BK20230937).
文摘Redox-active organic compounds have received much attention as high-capacity electrodes for rechargeable batteries.However,the high solubility in organic electrolytes during charge and discharge processes hinders the practical exploitation of organic compounds.This study presents a cobalt-based metal–organic coordination compound with bifunctional coordinated water(Co-MOC-H_(2)O)for sodium-ion storage.The coordinated water enhances interactions between sodium ions and nitrogen atoms in organic ligands through chelation,activating the inert sodium-ion storage sites(C=N).Moreover,the stable hydrogen bonded framework formed by the coordinated water molecules prevents the active organic compounds from dissolving into the electrolyte,thereby enhancing cycling stability.With the bifunctional coordinated water molecules,the Co-MOC-H_(2)O electrode delivers a high capacity of 403 mAh g^(-1)at 0.2 A g^(-1)over 600 cycles and exhibits a capacity retention of 77.9%at 2 A g^(-1)after 1100 cycles.This work highlights the crucial role of the coordinated water molecules in constructing high capacity and long-life sodium-ion storage materials.
文摘The coordinated regional development strategy,recognized as one of China’s seven development strategies,plays a crucial role in reducing regional development disparities,optimizing resource allocation,and facilitating high-quality development.This study analyzes a total of 418 relevant publications from China spanning the years 1998 to 2022.Utilizing CiteSpace software,a visualization analysis of keyword cooccurrence,mutation,and other bibliometric characteristics was conducted.The findings indicate that the number of publications during the specified period exhibited a fluctuating upward trend,with a notable increase observed after 2018.Furthermore,the research demonstrated a weak interdisciplinary crossover and a low intensity of collaboration among authors.The primary thematic areas of focus were identified as follows:connotation,mechanisms,countermeasure and suggestion,and evaluation.
基金supported by National Key R&D Program of ChinaunderGrant,(2021YFB2601403).
文摘Conventional coordinated control strategies for DC bus voltage signal(DBS)in islanded DC microgrids(IDCMGs)struggle with coordinating multiple distributed generators(DGs)and cannot effectively incorporate state of charge(SOC)information of the energy storage system,thereby reducing the system flexibility.In this study,we propose an adaptive coordinated control strategy that employs a two-layer fuzzy neural network controller(FNNC)to adapt to varying operating conditions in an IDCMG with multiple PV and battery energy storage system(BESS)units.The first-layer FNNC generates optimal operating mode commands for each DG,thereby avoiding the requirement for complex operating modes based on SOC segmentation.An optimal switching sequence logic prioritizes the most appropriate units during mode transitions.The second-layer FNNC dynamically adjusts the droop power to overcome power distribution challenges among DG groups.This helps in preventing the PV power from exceeding the limits and mitigating the risk of BESS overcharging or over-discharging.The simulation results indicate that the proposed strategy enhances the coordinated operation of multi-DG IDCMGs,thereby ensuring the efficient and safe utilization of PV and BESS.
基金financially supported by the National Natural Science Foundation of China(52472093,52176185)the Department of Science and Technology of Hubei Province of China(2022CFA069,2022BAA086)。
文摘The disorganized lithium dendrites and unstable solid electrolyte interphase(SEI)severely impede the practical application of lithium metal batteries(LMBs).Herein,the N-Zn-F coordinated triazine-based covalent organic framework(TTA-COF-ZnF_(2))is fabricated for the first time as an artificial SEI layer on the surface of lithium metal anodes(LMAs)to handle these issues.Zn-N coordination in onedimensional(1D)ordered COF can increase lithiophilic sites,reduce the Li-nucleation barrier,and regulate the Li+local coordination environment by optimizing surface charge density around the Zn metal.The electron-rich state induced by strong electron-withdrawing F-groups constructs electronegative nanochannels,which trigger efficient Li+desolvation.These beneficial attributes boost Li^(+)transfer,and homogenize Li^(+)flux,leading to uniform Li deposition.Besides,the lithiophilic triazine ring polar groups in TTA-COF-ZnF_(2)further facilitate the Li^(+)migration.The latent working mechanism of adjusting Li deposition behaviors and stabilizing LMAs for TTA-COF-ZnF_(2)is illustrated by detailed in-situ/ex-situ characterizations and density functional theory(DFT)calculations.As expected,TTA-COF-ZnF_(2)-modified Li|Cu half cells deliver a higher Coulombic efficiency(CE)of 98.4% over 250 cycles and lower nucleation overpotential(11 mV)at 1 mA cm^(-2),while TTA-COF-ZnF_(2)@Li symmetric cells display a long lifespan over3785 h at 2 mA cm^(-2).The TTA-COF-ZnF_(2)@Li|S full cells exert ultra high capacity retention of 81%(837 mA h g^(-1))after 600 cycles at 1C.Besides,the TTA-COF-ZnF_(2)@Li|LFP full cells with a high loading of 7.1 mg cm^(-2)exert ultrahigh capacity retention of 89%(108 mAh g^(-1))after 700 cycles at 5C.This synergistic strategy in N-Zn-F coordinated triazine-based COF provides a new insight to regulate the uniform platins/stripping behaviors for developing ultra-stable and dendrite-free LMBs.
基金This paper presents preliminary research findings from two projects:a major project funded by the National Social Science Fund of China,titled“Changes in the Nature of Rural Poverty in China in the New Era and Research on Post-2020 Anti-Poverty Policies”(Project No:19ZDA116)Doctoral Research Project under the Special Program for Talents in Shortage Areas Serving National Needs,Nanjing University of Finance and Economics,titled“The Impact of Policy-Based Agricultural Insurance on Farmers’Income and Welfare Levels”(Project No:BSZX2021-12).
文摘Agricultural insurance plays a key role in promoting the coordinated development of green agriculture and farmers’income growth,which is crucial for China’s high-quality agricultural development.Using the coupling coordination degree model,this study empirically demonstrates that the development of agricultural insurance significantly promotes the coordinated development of green agriculture and farmers’income growth once a certain threshold is exceeded.This effect is more pronounced in the major grain-producing regions and the central provinces.Expanding the scale of agricultural production and increasing investment in agricultural technology are the key mechanisms through which agricultural insurance supports the dual goals of green agriculture and income growth in China.In conclusion,this study proposes several policy recommendations,which include increasing investment in agricultural insurance infrastructure,strengthening the policy guidance for agricultural insurance,and designing differentiated agricultural insurance policies.
基金supported by the Na⁃tional Key R&D Program of China(No.2022YFC2204800)the Graduate Student Independent Exploration and Innovation Program of Central South University(No.2024ZZTS 0767).
文摘This paper concerns the exponential attitude-orbit coordinated control problems for gravitational-wave detection formation spacecraft systems.Notably,the large-scale communication delays resulting from oversized inter-satellite distance of space-based laser interferometers are first modeled.Subject to the delayed communication behaviors,a new delay-dependent attitude-orbit coordinated controller is designed.Moreover,by reconstructing the less conservative Lyapunov-Krasovskii functional and free-weight matrices,sufficient criteria are derived to ensure the exponential stability of the closed-loop relative translation and attitude error system.Finally,a simulation example is employed to illustrate the numerical validity of the proposed controller for in-orbit detection missions.
基金Under the auspices of National Natural Science Foundation of China(No.42471227,42171198)。
文摘The exploration of the coupling and coordination between urban innovation capability(IC)and industrial transformation(IF)serves as a novel perspective for interpreting the increasingly severe phenomenon of population shrinkage during the industrialization process.This study investigated the evolutionary characteristics of IC and IF in shrinking and growing cities in Northeast China from 2010 to 2020.It uses entropy weighted model,coupling coordination degree,the Dagum Gini coefficient,and geographic detectors to analyze the coordinated development of IC and IF in the context of population shrinkage.The study analyzed the spatiotemporal patterns and driving mechanisms for their coordinated development.The results show that:1)both urban IC and IF exhibited an overall positive trend during the study period.Shrinking cities depend more on IF to address the challenges of population shrinkage,while growing cities mainly rely on innovation-driven development.2)The coupling gap between IC and IF in shrinking and growing cities has widened over time,with the coordination level of shrinking cities steadily decreasing.Cities with serious disorder are concentrated in northern Heilongjiang Province,while most cities in Jilin Province experience moderate disorder.Liaoning Province,however,shows generally good coupling coordination.3)Human capital is the key factor driving coupling coordination in both types of cities.Shrinking cities rely on economic and financial development,with the‘repair-type’logic that emphasizes short-term economic growth and resource compensation.In contrast,the coupling of growing cities relies on basic support capabilities,with the‘optimization-type’logic focused on enhancing endogenous resilience and systemic coordination.Exploring the coordination between urban innovation capabilities and industrial transformation can provide a new perspective for research on population shrinkage,which holds certain theoretical and practical significance for implementing the new round of revitalization strategy in Northeast China.
基金supported in part by the Fundamental Research Funds for the Central Universi-ties(No.NP2022416)the Aeronautical Science Founda-tion of China(No.2022Z029052001).
文摘During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To address this issue,the rear landing gear is typically designed to steer in coordination with the nose wheels,reducing sideslip and improving maneuverability.This study examines how structural parameters and weight distribution affect the performance of coordinated steering in landing gear design for large transport aircraft.Using the C-5 transport aircraft as a case study,we develop a multi-wheel ground steering dynamics model,incorporating the main landing gear(MLG)deflection.A ground handling dynamics model is also established to evaluate the benefits of coordinated steering for rear MLG during steering.Additionally,the study analyzes the impact of structural parameters such as stiffness and damping on the steering performance of the C-5.It further investigates the effects of weight distribution,including the center-of-gravity(CG)height,the longitudinal CG position,and the mass asymmetry.Results show that when the C-5 employs coordinated steering for rear MLG,the lateral friction coefficients of the NLG tires decrease by 22%,24%,26%,and 27%.The steering radius is reduced by 29.7%,and the NLG steering moment decreases by 19%,significantly enhancing maneuverability.Therefore,in the design of landing gear for large transport aircraft,coordinated MLG steering,along with optimal structural and CG position parameters,should be primary design objectives.These results provide theoretical guidance for the design of multi-wheel landing gear systems in large transport aircraft.
基金Supported by National Natural Science Foundation of China(Grant Nos.52222216,52202493,52202466,U24B20124)Hunan Provincial Natural Science Foundation of China(Grant No.2022JJ40059).
文摘Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4WIS)vehicles,the steering systems of the four wheels are relatively independent,and there are differences and uncertainties in individual steering dynamics,which lead to challenges for all four wheels in simultaneously satisfying the ASP and may deteriorate the vehicle path tracking performance.In response to this problem,this paper introduces a four-wheel consistent coordinated steering control for 4WIS vehicles.The algorithm innovatively reconfigures the Ackerman steering relationships as coupling constraints among the wheels,and utilizes the constraint-following method to design controller.The controller achieves uniform boundedness(UB)and uniform ultimate boundedness(UUB)of ASP constraint error.The Carsim/Simulink joint simulation results demonstrate that the algorithm guarantees the approximate satisfaction of ASP in both the transient and steady-state of the vehicle path tracking.Also,it significantly improves the path tracking performance.
基金supported by the National Natural Science Foundation of China(Nos.22102167 and U21A20317)。
文摘Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional theory(DFT)calculations,we systematically investigate the catalytic activity of iron-nitrogen-carbon based covalent organic frameworks(COF)monolayers with axially coordinated ligands(denotes as Fe N_(4)-X@COF,X refers to axial ligand,X=-SCN,-I,-H,-SH,-NO_(2),-Br,-ClO,-Cl,-HCO_(3),-NO,-ClO_(2),-OH,-CN and-F).The calculated results demonstrate that all the catalysts possess good thermodynamic and electrochemical stabilities.The different ligands axially ligated to the Fe active center could induce changes in the charge of the Fe center,which further regulates the interaction strength between intermediates and catalysts that governs the catalytic activity.Importantly,FeN_(4)-SH@COF and Fe N_(4)-OH@COF are efficient bifunctional catalysts for HER and OER,FeN_(4)-OH@COF and FeN_(4)-I@COF are promising bifunctional catalysts for OER and ORR.These findings not only reveal promising bifunctional HER/OER and OER/ORR catalysts but also provide theoretical guidance for designing optimum ironnitrogen-carbon based catalysts.
文摘A group optimal penetration strategy in complex attack and defense confrontation situation is proposed in this paper to solve the coordinated penetration decision-making problem of endo-atmospheric gliding simultaneous multi-missile penetration of interceptors.First,the problem of large search space of multi-missile coordinated penetration maneuvers is fully considered,and the flight corridor of multi-missile coordinated penetration is designed to constrain search space of multi-agent coordinated strategy,comprehensively considering path constraints and anticollision constraints of gliding multi-missile flight.Then,a multi-missile hierarchical coordinated decision-making mechanism based on confrontation situation is proposed,and the swarm penetration strategy is optimized with the goal of maximizing swarm penetration effectiveness.The upper layer plans the swarm penetration formation according to confrontation situation,and generates the swarm coordinated penetration trajectory based on Multi-Agent Deep Deterministic Policy Gradient(MADDPG)method.The lower layer interpolates and smooths penetration trajectory,and generates the penetration guidance command based on Soft Actor-Critic and Extended Proportional Guidance(SAC-EPG)method.Simulation results verify that the proposed multi-missile cooperative penetration method based on hierarchical reinforcement learning converges faster than the penetration method based on MADDPG,and can quickly learn multi-missile cooperative penetration skills.In addition,multi-missile coordination can give full play to the group's detection and maneuverability,and occupy favorable penetration time and space through coordinated ballistic maneuvers.Thus the success rate of group penetration can be improved.
基金supported by the Natural Science Foundation of China(Nos.22278094 and 22379033)Guangdong Graduate Education Innovation Program(No.2023JGXM_102)+2 种基金the Basic and Applied Basic Research Program of Guangzhou(No.SL2024A03J00499)the University Innovation Team Scientific Research Project of Guangzhou(No.202235246)Hainan Province Graduate Innovation Research Project(No.Qhyb2023-143).
文摘Four-electron oxygen evolving reaction is limited by proton adsorption and desorption,making its reaction kinetics sluggish,which poses a major challenge for catalyst design.Here,we present an unsaturated coordination interface by constructing a fast electron transfer channel between Cu_(2)V_(2)O_(7)(CVO)and BiVO4(BVO).X-ray absorption spectroscopy(XAS)and theoretical calculations results confirm that CVO and BVO between interfaces are bonded by the way of unsaturated coordination oxygen(Ouc).The Ouc optimizes the O-O coupled energy barrier at the V active site and promotes the disconnection of O-H bond,which increases the photocurrent intensity of CVO by 6 times.In addition,due to the high electronegativity of the Ouc,the bonding energies of Bi-O and Cu-O at the interface are enhanced,resulting in the long-term stability of the photoanode during the water splitting.Finally,by integrating the working electrode with a polysilicon solar cell,we assembled a device that demonstrated exceptional catalytic performance,achieving a hydrogen production rate of 100.6μmol·cm^(-2),and maintaining a hydrogen-to-oxygen volume ratio of 2:1 after continuous operation for 4 h.This discovery aids in a deeper understanding of photoanode design and offers further insights for industrial applications.
基金supported in part by the National Key R&D Program of China(No.2023YFB4704400)in part by the National Natural Science Foundation of China(Nos.U23B2036,U2013201).
文摘In this paper,a distributed Event-Triggered(ET)collision avoidance coordinated control for Quadrotor Unmanned Aerial Vehicles(QUAVs)is proposed based on Virtual Tubes(VTs)with flexible boundaries in the presence of unknown external disturbances.Firstly,VTs are constructed for each QUAV,and the QUAV is restricted into the corresponding VT by the artificial potential field,which is distributed around the boundary of the VT.Thus,the collisions between QUAVs are avoided.Besides,the boundaries of the VTs are flexible by the modification signals,which are generated by the self-regulating auxiliary systems,to make the repulsive force smaller and give more buffer space for QUAVs without collision.Then,a novel ET mechanism is designed by introducing the concept of prediction to the traditional fixed threshold ET mechanism.Furthermore,a disturbance observer is proposed to deal with the adverse effects of the unknown external disturbance.On this basis,a distributed ET collision avoidance coordinated controller is proposed.Then,the proposed controller is quantized by the hysteresis uniform quantizer and then sent to the actuator only at the ET instants.The boundedness of the closed-loop signals is verified by the Lyapunov method.Finally,simulation and experimental results are performed to demonstrate the superiority of the proposed control method.
文摘Ports,the core hub of global supply chains,serve as vital links in the economic and trade exchanges among countries.Efficient,safe,green and smart ports are essential for the smooth operation of global trade.Recently,ISO established ISO/TC 8/SC 27,Ports and terminals,the secretariat of which is held by China.This is a big breakthrough of China’s participation in the international standardization activities in the area of transportation.
基金supported by the National Natural Science Foundation of China(Grant nos.82272003,82302195,and 82371976)the China Postdoctoral Science Foundation(Grant no.2024M752237)+1 种基金the Sichuan Science and Technology Program(Grant no.2024YFHZ0271)PostDoctor Research Project,Sichuan University(Grant nos.2024SCU12029 and 2023SCU12070).
文摘A tumor cell membrane(CM)-based biomimetic membrane tumor vaccine is an emerging prevention and treatment strategy in tumor immunotherapy.However,a single CM mostly has a weak immune-boosting effect.Here,a heterogenic fusion membrane tumor vaccine,EV–CM,was successfully constructed by fusing extracellular vesicles(EVs)from S.aureus and CM from B16F10 melanoma cells.Inheriting the advantages of parental components,the EV–CM combines tumor antigens with natural adjuvants that can be used for immunotherapy and can be easily synergistic with complementary therapies.In vivo vaccine tests have shown that EV–CM can activate immune antitumor responses and prevent tumorigenesis.To further enhance the immunotherapeutic and antimetastatic effects of EV–CM,Pt-porphyrin coordination polymer as an immunopotentiator(CPIP)was implanted into an EV–CM nanoplatform(CPIP@EV–CM),which combines localized sonodynamic/chemodynamic therapy-induced immunogenic cell death with heterogenic fusion membrane-mediated antigen-presenting functions.In vitro performance tests,cell experiments,and in vivo animal models have confirmed that the CPIP@EV–CM combined with US has better ROS production,tumor cell killing,and antimetastasis abilities.The heterogenic fusion membrane strategy and ultrasound-augmented nanoplatform present exciting prospects for designing tumor-immunogenic,self-adjuvant,and expandable vaccines,providing new ideas for exploring new melanoma immunotherapy and antimetastasis strategies,which is expected to be used as a safe and effective treatment in clinical practice.
基金supported by the National Natural Science Foundation of China(No.91844301)by the Beijing Municipal Natural Science Fund(No.JQ21030)。
文摘The coordinated control of PM_(2.5)and ozone has become the strategic goal of national air pollution control.Considering the gradual decline in PM_(2.5)concentration and the aggravation of ozone pollution,a better understanding of the coordinated control of PM_(2.5)and ozone is urgently needed.Here,we collected and sorted air pollutant data for 337 cities from 2015 to 2020 to explore the characteristics of PM_(2.5)and ozone pollution based on China’s five major air pollution regions.The results show that it is necessary to continue to strengthen the emission reduction in PM_(2.5)and ozone precursors,and control NO_(x) and VOCs while promoting a dramatic emission reduction in PM_(2.5).The primary method of curbing ozone pollution is to strengthen the emission control of VOCs,with a long-term strategy of achieving substantial emission reductions in NO_(x),because VOCs and NO_(x) are also precursors to PM_(2.5);hence,their reductions also contribute to the reduction in PM_(2.5).Therefore,the implementation of a multipollutant emission reduction control strategy aimed at the prevention and control of PM_(2.5)and ozone pollution is the only means to realize the coordinated control of PM_(2.5)and ozone.
基金supported by the Chengdu University of Technology“Double First-Class”initiative Construction Philosophy and Social Sciences Key Construction Project(No.ZDJS202202)the Research on the realization path and strategy of strategic mineral resources supply security under the new road of Chinese modernization(No.SCKCZY2023-ZD002)The Second Tibetan Plateau Scientific Expedition and Research(No.2021QZKK0305)。
文摘Comprehensive analysis of the Economy-Energy-Carbon Emission(EECE)system is beneficial for promoting sustainable social development.This study analyzes the system development of major watersheds in China from 2010 to 2019.The research fully considers the system’s internal and external inputs and outputs and proposes an evaluation index system for regional EECE coupling and coordinated development.Then,using the difference in system weight allocation to improve the coupling and coordination model,the study explores the dynamic system’s coupling and coordination.The results show that(1)The development of the system structure is relatively stable,but the overall development status is not ideal;(2)The downstream of China’s main river basins has obvious economic advantages,while the energy system fluctuates greatly.The efficiency of the carbon emission system will decrease in areas with rapid economic development.The coupling and coordination level of the EECE system is better in the Yangtze River Basin than in the Yellow River Basin;(3)From the perspective of dynamic coordinated development,the main river basins have been divided into two states since 2012,but it is relatively stable overall.Regional dynamic coordination is often at a disadvantage in regions with rapid economic and energy development;(4)The coupling coordination degree of the two river basins has significant positive spatial autocorrelation.Most provinces’significant spatial clustering characteristics of the coupling coordination degree are High-High type.Low-Low type provinces are mainly concentrated downstream.The research process has certain reference significance for the collaborative governance of complex regional systems.
基金the financial support from the Natural Science Foundation of China(Grant No.52172106)Anhui Provincial Natural Science Foundation(Grant Nos.2108085QB60 and 2108085QB61)China Postdoctoral Science Foundation(Grant Nos.2020M682057 and 2023T160651).
文摘Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.
基金The Second Tibetan Plateau Scientific Expedition and Research Program(STEP),No.2019QZKK0608。
文摘In this study,the interplay between ecosystem services and human well-being in Seni district,which is a pastoral region of Nagqu city on the Qinghai-Tibet Plateau,is investigated.Employing the improved InVEST model,CASA model,coupling coordination model,and hierarchical clustering method,we analyze the spatiotemporal patterns of ecosystem services,the levels of resident well-being levels,and the interrelationships between these factors over the period from 2000 to 2018.Our findings reveal significant changes in six ecosystem services,with water production decreasing by 7.1%and carbon sequestration and soil conservation services increasing by approximately 6.3%and 14.6%,respectively.Both the habitat quality and landscape recreation services remained stable.Spatially,the towns in the eastern and southern areas exhibited higher water production and soil conservation services,while those in the central area exhibited greater carbon sequestration services.The coupling and coordination relationship between ecosystem services and human well-being improved significantly over the study period,evolving from low-level coupling to coordinated coupling.Hierarchical clustering was used to classify the 12 town-level units into five categories.Low subjective well-being townships had lower livestock breeding services,while high subjective well-being townships had higher supply,regulation,and support ecosystem services.Good transportation conditions were associated with higher subjective well-being in townships with low supply services.We recommend addressing the identified transportation disparities and enhancing key regulatory and livestock breeding services to promote regional sustainability and improve the quality of life for Seni district residents,thus catering to the diverse needs of both herdsmen and citizens.
