Solving the absent assignment problem of the shortest time limit in a weighted bipartite graph with the minimal weighted k-matching algorithm is unsuitable for situations in which large numbers of problems need to be ...Solving the absent assignment problem of the shortest time limit in a weighted bipartite graph with the minimal weighted k-matching algorithm is unsuitable for situations in which large numbers of problems need to be addressed by large numbers of parties. This paper simplifies the algorithm of searching for the even alternating path that contains a maximal element using the minimal weighted k-matching theorem and intercept graph. A program for solving the maximal efficiency assignment problem was compiled. As a case study, the program was used to solve the assignment problem of water piping repair in the case of a large number of companies and broken pipes, and the validity of the program was verified.展开更多
Energy efficiency is closely related to the evolution of biological systems and is important to their information processing. In this work, we calculate the excitation probability of a simple model of a bistable biolo...Energy efficiency is closely related to the evolution of biological systems and is important to their information processing. In this work, we calculate the excitation probability of a simple model of a bistable biological unit in response to pulsatile inputs, and its spontaneous excitation rate due to noise perturbation. Then we analytically calculate the mutual information, energy cost, and energy efficiency of an array of these bistable units. We find that the optimal number of units could maximize this array＇s energy efficiency in encoding pulse inputs, which depends on the fixed energy cost. We conclude that demand for energy efficiency in biological systems may strongly influence the size of these systems under the pressure of natural selection.展开更多
The subdistrict office is the most grass-roots government organization, and is also the main unit providing services for the masses at the grass-roots level. In order to ensure the work efficiency of the subdistrict o...The subdistrict office is the most grass-roots government organization, and is also the main unit providing services for the masses at the grass-roots level. In order to ensure the work efficiency of the subdistrict office, it is necessary to strengthen the modernization of the subdistrict office. However, due to the influence of traditional management concepts for a long time, the street offices in many areas of our country still adopt traditional management methods when carrying out human resources management, which is difficult to motivate the staff. If this situation cannot be changed in time, it will affect the service efficiency of the street offices and the grassroots will be full of complaints, which will not only affect the image of the national government agencies, but also affect the stability of the street residents.展开更多
With the rapid increasing of maritime activities, maritime wireless networks(MWNs) with high reliability, high energy efficiency, and low delay are required. However, the centralized networking with fixed resource sch...With the rapid increasing of maritime activities, maritime wireless networks(MWNs) with high reliability, high energy efficiency, and low delay are required. However, the centralized networking with fixed resource scheduling is not suitable for MWNs due to the special environment. In this paper,we introduce the collaborative relay communication in distributed MWNs to improve the link reliability, and propose an orthogonal time-frequency resource block reservation based multiple access(RRMA) scheme for both one-hop direct link and two-hop collaborative relay link to reduce the interference. To further improve the network performance, we formulate an energy efficiency(EE) maximization resource allocation problem and solve it by an iterative algorithm based on the Dinkelbach method. Finally, numerical results are provided to investigate the proposed RRMA scheme and resource allocation algorithm, showing that the low outage probability and transmission delay can be attained by the proposed RRMA scheme. Moreover,the proposed resource allocation algorithm is capable of achieving high EE in distributed MWNs.展开更多
As a promising technology to improve spectrum efficiency and transmission coverage,Heterogeneous Network(HetNet)has attracted the attention of many scholars in recent years.Additionally,with the introduction of the No...As a promising technology to improve spectrum efficiency and transmission coverage,Heterogeneous Network(HetNet)has attracted the attention of many scholars in recent years.Additionally,with the introduction of the Non-Orthogonal Multiple Access(NOMA)technology,the NOMA-assisted HetNet cannot only improve the system capacity but also allow more users to utilize the same frequency band resource,which makes the NOMA-assisted HetNet a hot topic.However,traditional resource allocation schemes assume that base stations can exactly estimate direct link gains and cross-tier link gains,which is impractical for practical HetNets due to the impact of channel delays and random perturbation.To further improve energy utilization and system robustness,in this paper,we investigate a robust resource allocation problem to maximize the total Energy Efficiency(EE)of Small-Cell Users(SCUs)in NOMA-assisted HetNets under imperfect channel state information.By considering bounded channel uncertainties,the robust resource optimization problem is formulated as a mixed-integer and nonlinear programming problem under the constraints of the cross-tier interference power of macrocell users,the maximum transmit power of small base station,the Resource Block(RB)assignment,and the quality of service requirement of each SCU.The original problem is converted into an equivalent convex optimization problem by using Dinkelbach's method and the successive convex approximation method.A robust Dinkelbach-based iteration algorithm is designed by jointly optimizing the transmit power and the RB allocation.Simulation results verify that the proposed algorithm has better EE and robustness than the existing algorithms.展开更多
Short term uptake experiments and long term semicontinuous culture experiments were performed under the condition of phosphorus (P) limitation to estimate and compare the P uptake and growth kinetics of the microalga ...Short term uptake experiments and long term semicontinuous culture experiments were performed under the condition of phosphorus (P) limitation to estimate and compare the P uptake and growth kinetics of the microalga Tetraselmis subcordiformis and the macroalga Ulva pertusa. Two new parameters, the maximum specific uptake rate ( V sp m) and the maximal growth efficiency ( β ), are introduced to achieve uniformity for the comparison of nutrient uptake and growth efficiency between microalgae and macroalgae. T. subcordiformis possesses 3 times lower half saturation uptake constant, 4 times higher maximal growth rate and 20 times higher maximum specific uptake rate than U. pertusa, while U. pertusa possesses 4 times higher maximal growth efficiency than T. subcordiformis.展开更多
The space-air-ground integrated network(SAGIN)has gained widespread attention from academia and industry in recent years.It is widely applied in many practical fields such as global observation and mapping,intelligent...The space-air-ground integrated network(SAGIN)has gained widespread attention from academia and industry in recent years.It is widely applied in many practical fields such as global observation and mapping,intelligent transportation systems,and military missions.As an information carrier of air platforms,the deployment strategy of unmanned aerial vehicles(UAVs)is essential for communication systems’performance.In this paper,we discuss a UAV broadcast coverage strategy that can maximize energy efficiency(EE)under terrestrial users’requirements.Due to the non-convexity of this issue,conventional approaches often solve with heuristics algorithms or alternate optimization.To this end,we propose an iterative algorithm by optimizing trajectory and power allocation jointly.Firstly,we discrete the UAV trajectory into several stop points and propose a user grouping strategy based on the traveling salesman problem(TSP)to acquire the number of stop points and the optimization range.Then,we use the Dinkelbach method to dispose of the fractional form and transform the original problem into an iteratively solvable convex optimization problem by variable substitution and Taylor approximation.Numerical results validate our proposed solution and outperform the benchmark schemes in EE and mission completion time.展开更多
Fluorescence-based maximal photochemical efficiency, Fv/Fm, is widely used as an indicator to photosynthetic competence in marine systems. It has been considered a useful parameter diagnosing the nutrient stress on ph...Fluorescence-based maximal photochemical efficiency, Fv/Fm, is widely used as an indicator to photosynthetic competence in marine systems. It has been considered a useful parameter diagnosing the nutrient stress on phytoplankton photosynthesis, but many studies argue its usefulness. In the present study, we try to find a temporal relationship between Fv/Fm and nitrogen concentration, and provide a possible explanation on the controversy. We continuously measured Fv/Fm and nitrogen concentration once every 10 days from September 2003 to March 2004 at two stations in Jiaozhou Bay, northern China. It was found that Fv/ffm did not significantly correlate to synchronous nitrogen concentration, but the variation （i.e. the change between two adjacent cruises） of nitrogen concentration of the previous cruise and the variation ofFv/Fm of the current cruise were strongly correlated. This result indicates that a time lag exists between the variation of nutrient status and the subsequent Fv/Fm response. Length of the time lag seems just matched the interval of our measurements （10 days）. In the field, direct dependence of Fv/Fm on nitrogen concentration may not be found because of the lagged response of Fv/Fm to nitrogen concentration variations or physiological acclimation. Our results provide a possible way to explain the previously reported conflicting results on the relationship between Fv/Fm and nutrient status. To give a more-accurate estimate about the length of the time lag, an investigation that includes more frequent measurements is needed.展开更多
In view of the problems in the selection of alternatives which are mutually exclusive and the criticism against the increment principle, this article reveals the cause of the mistake and demonstrates that only the inc...In view of the problems in the selection of alternatives which are mutually exclusive and the criticism against the increment principle, this article reveals the cause of the mistake and demonstrates that only the increment principle and the incremental analysis method is the principle and method that we should follow and adopt in schematizing the economic policy-making.展开更多
The importance of optical resonance in enhancing light outcoupling efficiency(OCE)is frequently overlooked in conventional bottom-emitting quantum-dot light-emitting diodes(QLEDs)due to their weak microcavity effect.H...The importance of optical resonance in enhancing light outcoupling efficiency(OCE)is frequently overlooked in conventional bottom-emitting quantum-dot light-emitting diodes(QLEDs)due to their weak microcavity effect.Herein,we show that by synergistically optimizing the optical and the electrical performances,QLEDs with efficiency approaching the theoretical limit can be realized.By introducing a high refractive index indium zinc oxide(IZO)electrode and optimizing its thickness,the light OCE is significantly improved and consequently the red QLEDs exhibit an external quantum efficiency(EQE)of 33.2%,which is 1.4-fold higher than that of the reference devices with conventional indium tin oxide(ITO)electrodes.Moreover,with a high refractive index plastic substrate and a microlens array,the EQE can further be improved to a record value of 37.5%.Similar results are obtained in green and blue devices,which show an EQE of 18.8%and 14.4%,respectively.We also predict that the theoretical EQE limit of red,green,and blue QLEDs can reach 35.4%-36.5%,24.8%-34.0%,and 25.1%-35.8%,respectively,without using any light outcoupling structures.The proposed synergistic optimization strategy enables the efficiencies of red,green,and blue QLEDs to approach their theoretical limits.展开更多
Radio frequency identification (RFID) is one of today s most anticipated technologies for a broad range of enterprises. Based on the promise of lower operating costs combined with more accurate product and asset infor...Radio frequency identification (RFID) is one of today s most anticipated technologies for a broad range of enterprises. Based on the promise of lower operating costs combined with more accurate product and asset information, organizations .Rfrom manufacturers to government agencies, retailers to healthcare providers , Rare introducing RFID technologies in the supply chain, for asset tracking and management, and for security and regulatory purposes.展开更多
CONSPECTUS:Single-atom catalysts(SACs)represent a transformative advancement in heterogeneous catalysis,offering unparalleled opportunities for maximizing atomic efficiency and enhancing performance.SACs are character...CONSPECTUS:Single-atom catalysts(SACs)represent a transformative advancement in heterogeneous catalysis,offering unparalleled opportunities for maximizing atomic efficiency and enhancing performance.SACs are characterized by isolated metal atoms uniformly dispersed on suitable supports,ensuring each metal atom serves as an independent catalytic site.This dispersion mitigates metal atom aggregation,a common issue in conventional nanocatalysts,thus enabling superior activity,selectivity,and stability.Metal−organic frameworks(MOFs)have emerged as an ideal platform for SAC synthesis due to their structural diversity,tunable coordination environments,and high surface areas.MOFs provide well-defined coordination sites that facilitate the precise stabilization of single metal atoms,presenting significant advantages over traditional supports like metal oxides and metal materials.Carbonization of MOFs yields MOF-derived carbon materials that retain key structural characteristics while offering enhanced electrical conductivity and stability,making them suitable for various catalytic applications.Recent advances in the rational design and controlled synthesis of MOF-derived SACs have significantly improved their performance in electrocatalytic processes such as the oxygen reduction reaction(ORR)and carbon dioxide reduction reaction(CO_(2)RR).However,challenges remain,including maintaining structural integrity during high-temperature carbonization,enhancing mass and electron transport and ensuring the stability of isolated metal atoms under reaction conditions.To address these challenges,strategies such as using structure-directing agents to stabilize MOF frameworks,forming high-energy porous carbon networks,and optimizing support morphologies have been developed to maximize active site exposure and accessibility.On the other hand,the interplay between active metal sites and their coordination environments is crucial in determining the catalytic activity and selectivity of SACs.Advanced computational modeling,coupled with experimental validation,has provided insights into the electronic structure of SACs and the interactions between metal atoms and supports.These insights have enabled researchers to fine-tune local atomic coordination,leading to significant enhancements in performance.For instance,modifying the coordination environment of metal atoms optimizes the binding strength of reaction intermediates,thereby improving both activity and selectivity.This account highlights our group’s contributions to MOF-derived SACs,focusing on innovative design,functionalization,and synthesis approaches that enhance catalytic activity.Notable strategies include using structure-directing agents to maintain pore connectivity during carbonization,preserving high surface areas,and enhancing mass transport.We also discuss the design of high-energy MOFderived porous carbon networks that facilitate continuous electron transport and improve the interaction between active sites and reactants,ultimately boosting catalytic efficiency.Techniques such as electrospinning have also been employed to create hierarchical porous structures and one-dimensional nanofibers,enhancing mass transport and electron transfer.The rational design of SACs requires a comprehensive understanding of the microenvironment surrounding active sites,and by leveraging computational and experimental tools,researchers can precisely control these microenvironments to achieve desired outcomes.MOF-derived SACs hold substantial promise for energy conversion and chemical synthesis.Continued research is essential to optimize their design,improve scalability,and explore new applications,ultimately advancing sustainable catalysis.This account provides an overview of the latest advancements in MOF-derived SACs,highlighting their potential as next-generation electrocatalysts and their role in sustainable energy technologies.展开更多
文摘Solving the absent assignment problem of the shortest time limit in a weighted bipartite graph with the minimal weighted k-matching algorithm is unsuitable for situations in which large numbers of problems need to be addressed by large numbers of parties. This paper simplifies the algorithm of searching for the even alternating path that contains a maximal element using the minimal weighted k-matching theorem and intercept graph. A program for solving the maximal efficiency assignment problem was compiled. As a case study, the program was used to solve the assignment problem of water piping repair in the case of a large number of companies and broken pipes, and the validity of the program was verified.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11105062 and 11265014the Fundamental Research Funds for the Central Universities under Grant Nos LZUJBKY-2011-57 and LZUJBKY-2015-119
文摘Energy efficiency is closely related to the evolution of biological systems and is important to their information processing. In this work, we calculate the excitation probability of a simple model of a bistable biological unit in response to pulsatile inputs, and its spontaneous excitation rate due to noise perturbation. Then we analytically calculate the mutual information, energy cost, and energy efficiency of an array of these bistable units. We find that the optimal number of units could maximize this array＇s energy efficiency in encoding pulse inputs, which depends on the fixed energy cost. We conclude that demand for energy efficiency in biological systems may strongly influence the size of these systems under the pressure of natural selection.
文摘The subdistrict office is the most grass-roots government organization, and is also the main unit providing services for the masses at the grass-roots level. In order to ensure the work efficiency of the subdistrict office, it is necessary to strengthen the modernization of the subdistrict office. However, due to the influence of traditional management concepts for a long time, the street offices in many areas of our country still adopt traditional management methods when carrying out human resources management, which is difficult to motivate the staff. If this situation cannot be changed in time, it will affect the service efficiency of the street offices and the grassroots will be full of complaints, which will not only affect the image of the national government agencies, but also affect the stability of the street residents.
基金supported in part by the National Natural Science Foundation of China under Grant 62001056, 61925101, U21A20444in part by the Fundamental Research Funds for the Central Universities under Grant 500421336 and Grant 505021163。
文摘With the rapid increasing of maritime activities, maritime wireless networks(MWNs) with high reliability, high energy efficiency, and low delay are required. However, the centralized networking with fixed resource scheduling is not suitable for MWNs due to the special environment. In this paper,we introduce the collaborative relay communication in distributed MWNs to improve the link reliability, and propose an orthogonal time-frequency resource block reservation based multiple access(RRMA) scheme for both one-hop direct link and two-hop collaborative relay link to reduce the interference. To further improve the network performance, we formulate an energy efficiency(EE) maximization resource allocation problem and solve it by an iterative algorithm based on the Dinkelbach method. Finally, numerical results are provided to investigate the proposed RRMA scheme and resource allocation algorithm, showing that the low outage probability and transmission delay can be attained by the proposed RRMA scheme. Moreover,the proposed resource allocation algorithm is capable of achieving high EE in distributed MWNs.
基金This work was supported by the National Natural Science Foundation of China(No.61601071,62071078)the National Key Research and Development Program of China(No.2019YFC1511300)+2 种基金the Natural Science Foundation of Chongqing(No.cstc2019jcyj-xfkxX0002)the Chongqing Entrepreneurship and Innovation Program for the Returned Overseas Chinese Scholars(No.cx2020095)the Graduate Scientific Research Innovation Project of Chongqing(No.CYS20251,CYS20253).
文摘As a promising technology to improve spectrum efficiency and transmission coverage,Heterogeneous Network(HetNet)has attracted the attention of many scholars in recent years.Additionally,with the introduction of the Non-Orthogonal Multiple Access(NOMA)technology,the NOMA-assisted HetNet cannot only improve the system capacity but also allow more users to utilize the same frequency band resource,which makes the NOMA-assisted HetNet a hot topic.However,traditional resource allocation schemes assume that base stations can exactly estimate direct link gains and cross-tier link gains,which is impractical for practical HetNets due to the impact of channel delays and random perturbation.To further improve energy utilization and system robustness,in this paper,we investigate a robust resource allocation problem to maximize the total Energy Efficiency(EE)of Small-Cell Users(SCUs)in NOMA-assisted HetNets under imperfect channel state information.By considering bounded channel uncertainties,the robust resource optimization problem is formulated as a mixed-integer and nonlinear programming problem under the constraints of the cross-tier interference power of macrocell users,the maximum transmit power of small base station,the Resource Block(RB)assignment,and the quality of service requirement of each SCU.The original problem is converted into an equivalent convex optimization problem by using Dinkelbach's method and the successive convex approximation method.A robust Dinkelbach-based iteration algorithm is designed by jointly optimizing the transmit power and the RB allocation.Simulation results verify that the proposed algorithm has better EE and robustness than the existing algorithms.
基金supported by the Project under Major State Basic Research of China(G1999012011).
文摘Short term uptake experiments and long term semicontinuous culture experiments were performed under the condition of phosphorus (P) limitation to estimate and compare the P uptake and growth kinetics of the microalga Tetraselmis subcordiformis and the macroalga Ulva pertusa. Two new parameters, the maximum specific uptake rate ( V sp m) and the maximal growth efficiency ( β ), are introduced to achieve uniformity for the comparison of nutrient uptake and growth efficiency between microalgae and macroalgae. T. subcordiformis possesses 3 times lower half saturation uptake constant, 4 times higher maximal growth rate and 20 times higher maximum specific uptake rate than U. pertusa, while U. pertusa possesses 4 times higher maximal growth efficiency than T. subcordiformis.
基金co-supported by National Natural Science Foundation of China (No. 62171158)the Major Key Project of PCL (PCL2021A03-1)
文摘The space-air-ground integrated network(SAGIN)has gained widespread attention from academia and industry in recent years.It is widely applied in many practical fields such as global observation and mapping,intelligent transportation systems,and military missions.As an information carrier of air platforms,the deployment strategy of unmanned aerial vehicles(UAVs)is essential for communication systems’performance.In this paper,we discuss a UAV broadcast coverage strategy that can maximize energy efficiency(EE)under terrestrial users’requirements.Due to the non-convexity of this issue,conventional approaches often solve with heuristics algorithms or alternate optimization.To this end,we propose an iterative algorithm by optimizing trajectory and power allocation jointly.Firstly,we discrete the UAV trajectory into several stop points and propose a user grouping strategy based on the traveling salesman problem(TSP)to acquire the number of stop points and the optimization range.Then,we use the Dinkelbach method to dispose of the fractional form and transform the original problem into an iteratively solvable convex optimization problem by variable substitution and Taylor approximation.Numerical results validate our proposed solution and outperform the benchmark schemes in EE and mission completion time.
基金Supported by the Public Science and Technology Research Funds of Ocean(No.200905019)the Science Foundation of Young Scientist,SOA(No.2011129)+1 种基金the Outstanding Young & Middle Scientist of Shandong Province(No.BS2010HZ018)the Taishan Scholar Fund of Aquatic Animal Nutrition and Feed to ZHANG Limin
文摘Fluorescence-based maximal photochemical efficiency, Fv/Fm, is widely used as an indicator to photosynthetic competence in marine systems. It has been considered a useful parameter diagnosing the nutrient stress on phytoplankton photosynthesis, but many studies argue its usefulness. In the present study, we try to find a temporal relationship between Fv/Fm and nitrogen concentration, and provide a possible explanation on the controversy. We continuously measured Fv/Fm and nitrogen concentration once every 10 days from September 2003 to March 2004 at two stations in Jiaozhou Bay, northern China. It was found that Fv/ffm did not significantly correlate to synchronous nitrogen concentration, but the variation （i.e. the change between two adjacent cruises） of nitrogen concentration of the previous cruise and the variation ofFv/Fm of the current cruise were strongly correlated. This result indicates that a time lag exists between the variation of nutrient status and the subsequent Fv/Fm response. Length of the time lag seems just matched the interval of our measurements （10 days）. In the field, direct dependence of Fv/Fm on nitrogen concentration may not be found because of the lagged response of Fv/Fm to nitrogen concentration variations or physiological acclimation. Our results provide a possible way to explain the previously reported conflicting results on the relationship between Fv/Fm and nutrient status. To give a more-accurate estimate about the length of the time lag, an investigation that includes more frequent measurements is needed.
文摘In view of the problems in the selection of alternatives which are mutually exclusive and the criticism against the increment principle, this article reveals the cause of the mistake and demonstrates that only the increment principle and the incremental analysis method is the principle and method that we should follow and adopt in schematizing the economic policy-making.
基金This work was supported by the National Natural Science Foundation of China(No.62174075)the Shenzhen Science and Technology Program(Nos.JCYJ20210324105400002 and JCYJ20220530113809022)the Guangdong University Research Program(No.2020ZDZX3062).
文摘The importance of optical resonance in enhancing light outcoupling efficiency(OCE)is frequently overlooked in conventional bottom-emitting quantum-dot light-emitting diodes(QLEDs)due to their weak microcavity effect.Herein,we show that by synergistically optimizing the optical and the electrical performances,QLEDs with efficiency approaching the theoretical limit can be realized.By introducing a high refractive index indium zinc oxide(IZO)electrode and optimizing its thickness,the light OCE is significantly improved and consequently the red QLEDs exhibit an external quantum efficiency(EQE)of 33.2%,which is 1.4-fold higher than that of the reference devices with conventional indium tin oxide(ITO)electrodes.Moreover,with a high refractive index plastic substrate and a microlens array,the EQE can further be improved to a record value of 37.5%.Similar results are obtained in green and blue devices,which show an EQE of 18.8%and 14.4%,respectively.We also predict that the theoretical EQE limit of red,green,and blue QLEDs can reach 35.4%-36.5%,24.8%-34.0%,and 25.1%-35.8%,respectively,without using any light outcoupling structures.The proposed synergistic optimization strategy enables the efficiencies of red,green,and blue QLEDs to approach their theoretical limits.
文摘Radio frequency identification (RFID) is one of today s most anticipated technologies for a broad range of enterprises. Based on the promise of lower operating costs combined with more accurate product and asset information, organizations .Rfrom manufacturers to government agencies, retailers to healthcare providers , Rare introducing RFID technologies in the supply chain, for asset tracking and management, and for security and regulatory purposes.
基金financially supported by the National Natural Science Foundation of China(52332007Z).
文摘CONSPECTUS:Single-atom catalysts(SACs)represent a transformative advancement in heterogeneous catalysis,offering unparalleled opportunities for maximizing atomic efficiency and enhancing performance.SACs are characterized by isolated metal atoms uniformly dispersed on suitable supports,ensuring each metal atom serves as an independent catalytic site.This dispersion mitigates metal atom aggregation,a common issue in conventional nanocatalysts,thus enabling superior activity,selectivity,and stability.Metal−organic frameworks(MOFs)have emerged as an ideal platform for SAC synthesis due to their structural diversity,tunable coordination environments,and high surface areas.MOFs provide well-defined coordination sites that facilitate the precise stabilization of single metal atoms,presenting significant advantages over traditional supports like metal oxides and metal materials.Carbonization of MOFs yields MOF-derived carbon materials that retain key structural characteristics while offering enhanced electrical conductivity and stability,making them suitable for various catalytic applications.Recent advances in the rational design and controlled synthesis of MOF-derived SACs have significantly improved their performance in electrocatalytic processes such as the oxygen reduction reaction(ORR)and carbon dioxide reduction reaction(CO_(2)RR).However,challenges remain,including maintaining structural integrity during high-temperature carbonization,enhancing mass and electron transport and ensuring the stability of isolated metal atoms under reaction conditions.To address these challenges,strategies such as using structure-directing agents to stabilize MOF frameworks,forming high-energy porous carbon networks,and optimizing support morphologies have been developed to maximize active site exposure and accessibility.On the other hand,the interplay between active metal sites and their coordination environments is crucial in determining the catalytic activity and selectivity of SACs.Advanced computational modeling,coupled with experimental validation,has provided insights into the electronic structure of SACs and the interactions between metal atoms and supports.These insights have enabled researchers to fine-tune local atomic coordination,leading to significant enhancements in performance.For instance,modifying the coordination environment of metal atoms optimizes the binding strength of reaction intermediates,thereby improving both activity and selectivity.This account highlights our group’s contributions to MOF-derived SACs,focusing on innovative design,functionalization,and synthesis approaches that enhance catalytic activity.Notable strategies include using structure-directing agents to maintain pore connectivity during carbonization,preserving high surface areas,and enhancing mass transport.We also discuss the design of high-energy MOFderived porous carbon networks that facilitate continuous electron transport and improve the interaction between active sites and reactants,ultimately boosting catalytic efficiency.Techniques such as electrospinning have also been employed to create hierarchical porous structures and one-dimensional nanofibers,enhancing mass transport and electron transfer.The rational design of SACs requires a comprehensive understanding of the microenvironment surrounding active sites,and by leveraging computational and experimental tools,researchers can precisely control these microenvironments to achieve desired outcomes.MOF-derived SACs hold substantial promise for energy conversion and chemical synthesis.Continued research is essential to optimize their design,improve scalability,and explore new applications,ultimately advancing sustainable catalysis.This account provides an overview of the latest advancements in MOF-derived SACs,highlighting their potential as next-generation electrocatalysts and their role in sustainable energy technologies.
