A new alkali metal borate fluoride Li_(3)KB_(9)O_(15)F has been successfully obtained by the high-temperature solution method in open air for the first time.An X-ray crystallographic study reveals that it crystallizes...A new alkali metal borate fluoride Li_(3)KB_(9)O_(15)F has been successfully obtained by the high-temperature solution method in open air for the first time.An X-ray crystallographic study reveals that it crystallizes in the trigonal space group R3c(no.161),a=11.974(4)Å,b=11.974(4)Å,c=15.998(11)Åand Z=6.It exhibits a complicated three-dimensional(3D)network composed of LiO_(3)F,KO_(6)F distorted polyhedra and 3D B–O framework.展开更多
Underground carbon sequestration(CS)by solid waste backfill(SWB)offers an effective pathway for collaborative disposal of coal-based solid waste and CO_(2),where the amount of carbon sequestration is an important eval...Underground carbon sequestration(CS)by solid waste backfill(SWB)offers an effective pathway for collaborative disposal of coal-based solid waste and CO_(2),where the amount of carbon sequestration is an important evaluation parameter.In this study,the concept of whole-process carbon sequestration using coal-based solid waste and CO_(2),including sequential stirring and curing stages,was proposed to evaluate the performance evolution of CS.The results showed that CO_(2) pressure and ambient temperature positively correlated with the CS amount from coal-based SWB.In particular,CO_(2) pressure prevailed in the stirring stage,while the ambient temperature effect was more significant in the curing stage.The CS amounts obtained during the stirring stage alone,the curing stage alone,and two sequential stages ranged from 0.66%–3.10%,3.53%–5.09%,and 5.12%–6.02%,respectively.The functional group and micromorphology analyses revealed that the prevailing mechanism at the CS stirring stage was the stirringdriven gas dissolution-leaching-mineralization reaction,while that at the curing stage was the hydration-driven gas permeation-dissociation-CS reaction.Both were essentially solid-liquid-gas multiphase chemical reactions.The results are instrumental in substantiating the coal-based SWB carbon sequestration evolution patterns and mechanisms and providing data support for waste disposal and carbon emission reduction in the coal industry.展开更多
This work is devoted to the development of a low cost dimensionally stable anode with high oxygen evolution catalytic activity for practical applications.For this purpose,a Ti/SnO_(x)/MnO_(2) anode was fabricated thro...This work is devoted to the development of a low cost dimensionally stable anode with high oxygen evolution catalytic activity for practical applications.For this purpose,a Ti/SnO_(x)/MnO_(2) anode was fabricated through an innovative strategy involving Sn electrodeposition,oxidation,and MnO_(2)-layer preparation.The structure of the anode was characterized,and the oxygen evolution performance was evaluated in a H_(2)SO_(4) solution.The results show that compared with the Ti/SnO_(2)/MnO_(2) anode prepared by the conventional brushing-annealing process,the Ti/SnO_(x)/MnO_(2) anode fabricated through the innovative procedure exhibits a lower oxygen evolution potential and a nearly 40%longer accelerated lifespan.The superior oxygen evolution performance of the Ti/SnO_(x)/MnO_(2) anode is attributed to the distinctive SnO_(x) intermediate layer fabricated through Sn electrodeposition followed by oxidation,which indicates the great potential of the anode as a dimensionally stable anode for metal electrowinning and hydrogen production by electrolysis,etc.展开更多
Motivated by the huge practical engineering demand for the fundamental understanding of mechanical characteristics of high-speed railway infrastructure,a fullscale multi-functional test platform for high-speed railway...Motivated by the huge practical engineering demand for the fundamental understanding of mechanical characteristics of high-speed railway infrastructure,a fullscale multi-functional test platform for high-speed railway track–subgrade system is developed in this paper,and its main functions for investigating the mechanical performance of track–subgrade systems are elaborated with three typical experimental examples.Comprising the full-scale subgrade structure and all the five types of track structures adopted in Chinese high-speed railways,namely the CRTS I,the CRTS II and the CRTS III ballastless tracks,the double-block ballastless track and the ballasted track,the test platform is established strictly according to the construction standard of Chinese high-speed railways.Three kinds of effective loading methods are employed,including the real bogie loading,multi-point loading and the impact loading.Various types of sensors are adopted in different components of the five types of track–subgrade systems to measure the displacement,acceleration,pressure,structural strain and deformation,etc.Utilizing this test platform,both dynamic characteristics and long-term performance evolution of high-speed railway track–subgrade systems can be investigated,being able to satisfy the actual demand for large-scale operation of Chinese high-speed railways.As examples,three typical experimental studies are presented to elucidate the comprehensive functionalities of the full-scale multi-functional test platform for exploring the dynamic performance and its long-term evolution of ballastless track systems and for studying the long-term accumulative settlement of the ballasted track–subgrade system in high-speed railways.Some interesting phenomena and meaningful results are captured by the developed test platform,which provide a useful guidance for the scientific operation and maintenance of high-speed railway infrastructure.展开更多
The±200 kV direct current(DC)cables of the Zhoushan Transmission Project were targeted,and crosslinked polyethylene(XLPE)insulation samples were prepared from faulty and spare cables.Samples were tested for oxida...The±200 kV direct current(DC)cables of the Zhoushan Transmission Project were targeted,and crosslinked polyethylene(XLPE)insulation samples were prepared from faulty and spare cables.Samples were tested for oxidation induction period,Fourier transform infrared spectroscopy,differential scanning calorimetry,thermally stimulated depolarisation current,space charge and DC dielectric strength.The evolution of performance parameters was analysed,and the insulation ageing characteristics of onsite operating DC cables were deduced.The results show that compared with spare cables,the carbonyl index of operating cables decreases,the crystallinity increases and DC dielectric strength increases slightly.It is inferred being related to the reduced content of antioxidants and crosslinking by-products and improved molecular chain and crystal microstructure of XLPE insulation.It is suggested that the insulation ageing of high voltage DC XLPE cable is divided into two stages.In the early stage,the secondary crosslinking and recrystallisation processes are dominant,and the thermal and electric effects make the material properties basically stable or even slightly improved.In the middle and later stage,the thermal oxygen reaction is dominant,the microstructure of the material is destroyed,with a large number of macromolecular chains broken and some crystalline regions transformed into amorphous ones,and the insulation properties degraded significantly.展开更多
Developing earth-abundant,highly active,and durable electrocatalysts for the oxygen evolution reaction(OER)is of crucial importance for renewable energy conversion processes.Herein,we fabricated novel flower-like NiFe...Developing earth-abundant,highly active,and durable electrocatalysts for the oxygen evolution reaction(OER)is of crucial importance for renewable energy conversion processes.Herein,we fabricated novel flower-like NiFe-layered double hydroxide nanostructures with electron-withdrawing anion intercalation and surface sulfurization via a two-step hydrothermal treatment.Benefiting from the dual-modified electronic structure of the surface active sites of NiFe-LDHs,the as-obtained catalyst showed excellent electrocatalytic activity for the OER,only demanding a low overpotential of 259 mV to achieve 10 mA cm^(-2) in 1.0 M KOH.展开更多
The availability of polymorphs of metallic complexes provides an opportunity to reveal the relationship between crystal packing and catalytic activity.Herein,we immobilize two stable concomitant polymorphs(green NiL_(...The availability of polymorphs of metallic complexes provides an opportunity to reveal the relationship between crystal packing and catalytic activity.Herein,we immobilize two stable concomitant polymorphs(green NiL_(2)-G and red NiL_(2)-R)of mononuclear nickel NiL_(2) on electrodes as heterogeneous oxygen evolution reaction catalysts.Density functional theory calculations reveal that the formation of L_(2)Ni^(Ⅳ)=O from L_(2)Ni^(Ⅲ)-OH is the rate-determining step,whereas R-L_(2)Ni^(Ⅲ)-OH is more stable than G-L_(2)Ni^(Ⅲ)-OH,and forming L_(2)Ni^(Ⅳ)=O from the former has a much lower barrier than from the latter.Consistently,NiL_(2)-R exhibits a lower overpotential(339 mV)than NiL_(2)-G(466 mV)at 10 mA cm^(-2).展开更多
Through first-principles structure search calculations,we have discovered a series of hitherto unknown two-dimensional(2D)Janus TMB_(2)O nanomaterials(TM=Fe,Co,Ni,Ru,Rh,Pd,Os,Ir and Pt)featuring a single atomic layer ...Through first-principles structure search calculations,we have discovered a series of hitherto unknown two-dimensional(2D)Janus TMB_(2)O nanomaterials(TM=Fe,Co,Ni,Ru,Rh,Pd,Os,Ir and Pt)featuring a single atomic layer of TM-metallene as one exposed surface resembling the atomic arrangement of Pt(111)surface,which can be well stabilized by a non-metallic BO exposed surface composed of hexagonal rings.Further,by substituting S atoms for O atoms,the TMB_(2)S series can be derived from these nine fascinating TMB_(2)O structures.All eighteen intriguing 2D Janus monolayers exhibit high thermodynamic,dynamical and mechanical stabilities,as well as good conductivity.展开更多
To better understand the resilience evolution dynamics of urban lifeline systems over extended operational periods,this study introduces a model inspired by the susceptible-infected-recovered(SIR)model,which is tradit...To better understand the resilience evolution dynamics of urban lifeline systems over extended operational periods,this study introduces a model inspired by the susceptible-infected-recovered(SIR)model,which is traditionally used to simulate population health transitions.By analyzing the mechanisms governing the performance state evolution of urban lifeline systems under disaster scenarios,integrating a disaster scenario model with resilience assessment methodologies,and comprehensively considering three key resilience components—resistance,recovery,and adaptability—we develop a system dynamics resilience-reliability(SDR-R)model.A hypothetical case study is conducted to validate the model's applicability.The results indicate that the interplay of resistance,recovery,and adaptability influences the dynamic evolution of system performance across three states:disability performance,survivability performance,and recovery performance.The model reveals a cyclical pattern in resilience enhancement,with adaptability emerging as a critical determinant.Moreover,the SDR-R model not only simulates urban lifeline performance state evolution under single disaster scenarios but also captures resilience evolution trends over long-term system operations.The case study findings reveal that resilience decreases as disaster severity intensifies,yet positive feedback from adaptability fosters resilience improvement over time.The process of resilience evolution can be divided into four distinct phases:initial impact,adaptive priming,adaptive enhancement,and threshold effect.Notably,resilience dynamics vary significantly across disaster levels.While systems exhibit high resilience under low-level disasters,resilience gradually stabilizes at a high level in medium-and high-level disaster scenarios.However,extreme disasters introduce greater fluctuations in resilience,underscoring the necessity for targeted resilience-enhancing strategies.The insights derived from this study offer methodological guidance for understanding urban lifeline resilience evolution and developing strategies to enhance system robustness.展开更多
Interstitial oxygen dopants(O_(i))in sulfide nanocrystals are more conducive to charge carrier separation for improving the photocatalytic hydrogen evolution(PHE)performance than substituted oxygen dopants(O_(S)).Howe...Interstitial oxygen dopants(O_(i))in sulfide nanocrystals are more conducive to charge carrier separation for improving the photocatalytic hydrogen evolution(PHE)performance than substituted oxygen dopants(O_(S)).However,oxygen dopants exist dominantly in the form of OS,rather than O_(i),in oxygen-doped sulfides prepared via traditional methods.展开更多
Heterostructure construction has become increasingly recognized as an effective strategy to enhance oxygen evolution reaction(OER)performance due to the exposed active surfaces and improved mass/charge transfer.Inspir...Heterostructure construction has become increasingly recognized as an effective strategy to enhance oxygen evolution reaction(OER)performance due to the exposed active surfaces and improved mass/charge transfer.Inspired by natural plant structures,this study develops a unique moss-like amorphous/crystalline(CoB/CeO_(2))heterojunction.This distinctive moss-like morphology facilitates the formation of staggered sheet structures in the catalyst,providing more active sites and open channels for reaction intermediates and gas release.Benefiting from the hydrophilic properties offered by the moss-like morphology,CoB/CeO_(2) exhibits excellent OER catalytic performance in 1 M KOH,requiring only 247 mV at 100 mA cm^(-2).Physicochemical characterization and mechanistic studies reveal that the close nanoscale features between CoB and CeO_(2) create abundant binary interfaces,optimize the electronic configuration,induce changes in electronic states,and provide abundant defect sites,thereby enhancing charge transfer capabilities.This work presents a new paradigm for the design of efficient and durable OER electrocatalysts.展开更多
To solve the slow dynamics of catalytic oxygen reaction energy devices,a facile method was developed for the synthesis of methylene alcohol terminated poly(1,4-phenyldiimine)porphyrin cobalt(MPImPorCo),which was synth...To solve the slow dynamics of catalytic oxygen reaction energy devices,a facile method was developed for the synthesis of methylene alcohol terminated poly(1,4-phenyldiimine)porphyrin cobalt(MPImPorCo),which was synthesized by RuCl_(3) catalyzed redox reaction of meso-5,10,15,20-tetra(4-nitrophenyl)porphyrin cobalt(TNO_(2)-PorCo)and 1,4-phenyldimethanol.M-PImPorCo is a fully conjugated covalent organic framework(COF)with high thermal and chemical stability.COFs with different edge groups were synthesized to compare the effect of different groups(–CH_(2)–OH and–NO_(2))on catalytic bifunctional oxygen reaction activity.C=N as nitrogen-rich environment of M-PImPorCo leads to the protonation process of oxygen catalysis and reduces the energy barrier of adsorption in the oxygen intermediate.C=N and–CH_(2)–OH form an“electron pump”structure to deliver electrons to the Co–N4 site in M-PImPorCo,and theπ–πinteraction between M-PImPorCo and three-dimensional graphene(3D-G)can further enrich the electron cloud density of Co–N_(4) sites.M-PImPorCo/3D-G has remarkable oxygen catalytic performance,with a half-wave potential(E_(1/2))of 0.91 V vs.reversible hydrogen electrode(RHE).M-PImPorCo/3D-G has low potential(Ej=10 is 1.49 V vs.RHE)at a current density of 10 mA·cm^(-2).It exhibits a good bifunctional catalytic performance(potential difference(ΔE)=0.58 V).The smaller charge–discharge band gap of zinc-air batteries(ZABs)and flexible ZABs(F-ZABs)equipped with M-PImPorCo/3D-G suggests the potential for catalytic oxygen reaction bifunctional applications.This work provides a new idea for the synthesis of Schiff-base porphyrin-based COF catalyst and its potential application to oxygen reaction catalytic energy storage devices.展开更多
基金supported by the Xinjiang International Science&Technology Cooperation Program(Grant No.2017E01014)Tianshan Innovation Team Program(Grant No.2018D14001)the National Natural Science Foundation of China(Grant No.U1703132)+6 种基金the Tianshan Xue Song Program“Xinjiang Youth Top Talent Backup Project”(Grant No.2017XS17),the National Key Research Project(Grant No.2016YFB1102302,2016YFB0402104)the Science and Technology Project of Urumqi(Grant No.P161010002)the Xinjiang Key Research and Development Program(Grant No.2016B02021)the Major Program of Xinjiang Uygur Autonomous Region of China during the 13th Five-Year Plan Period(Grant No.2016A02003)the West Light Foundation of the Chinese Academy of Sciences(Grant No.2016-YJRC-2)the Foundation of Director of XTIPC,CAS(Grant No.2016PY004)the Tianshan Xue Song Program“Xinjiang Youth Top Talent Backup Project”(Grant No.2017XS17).
文摘A new alkali metal borate fluoride Li_(3)KB_(9)O_(15)F has been successfully obtained by the high-temperature solution method in open air for the first time.An X-ray crystallographic study reveals that it crystallizes in the trigonal space group R3c(no.161),a=11.974(4)Å,b=11.974(4)Å,c=15.998(11)Åand Z=6.It exhibits a complicated three-dimensional(3D)network composed of LiO_(3)F,KO_(6)F distorted polyhedra and 3D B–O framework.
基金supported by the National Key R&D Program of China(No.2023YFC3904304)the National Natural Science Foundation of China(No.52304158)Jiangsu Key Laboratory for Clean Utilization of Carbon Resources Research Project(No.BM2024007)。
文摘Underground carbon sequestration(CS)by solid waste backfill(SWB)offers an effective pathway for collaborative disposal of coal-based solid waste and CO_(2),where the amount of carbon sequestration is an important evaluation parameter.In this study,the concept of whole-process carbon sequestration using coal-based solid waste and CO_(2),including sequential stirring and curing stages,was proposed to evaluate the performance evolution of CS.The results showed that CO_(2) pressure and ambient temperature positively correlated with the CS amount from coal-based SWB.In particular,CO_(2) pressure prevailed in the stirring stage,while the ambient temperature effect was more significant in the curing stage.The CS amounts obtained during the stirring stage alone,the curing stage alone,and two sequential stages ranged from 0.66%–3.10%,3.53%–5.09%,and 5.12%–6.02%,respectively.The functional group and micromorphology analyses revealed that the prevailing mechanism at the CS stirring stage was the stirringdriven gas dissolution-leaching-mineralization reaction,while that at the curing stage was the hydration-driven gas permeation-dissociation-CS reaction.Both were essentially solid-liquid-gas multiphase chemical reactions.The results are instrumental in substantiating the coal-based SWB carbon sequestration evolution patterns and mechanisms and providing data support for waste disposal and carbon emission reduction in the coal industry.
文摘This work is devoted to the development of a low cost dimensionally stable anode with high oxygen evolution catalytic activity for practical applications.For this purpose,a Ti/SnO_(x)/MnO_(2) anode was fabricated through an innovative strategy involving Sn electrodeposition,oxidation,and MnO_(2)-layer preparation.The structure of the anode was characterized,and the oxygen evolution performance was evaluated in a H_(2)SO_(4) solution.The results show that compared with the Ti/SnO_(2)/MnO_(2) anode prepared by the conventional brushing-annealing process,the Ti/SnO_(x)/MnO_(2) anode fabricated through the innovative procedure exhibits a lower oxygen evolution potential and a nearly 40%longer accelerated lifespan.The superior oxygen evolution performance of the Ti/SnO_(x)/MnO_(2) anode is attributed to the distinctive SnO_(x) intermediate layer fabricated through Sn electrodeposition followed by oxidation,which indicates the great potential of the anode as a dimensionally stable anode for metal electrowinning and hydrogen production by electrolysis,etc.
基金This work was supported by the National Natural Science Foundation of China[Grant Nos.11790283,51978587,51708457]the Program of Introducing Talents of Discipline to Universities(111 Project)[Grant No.B16041].
文摘Motivated by the huge practical engineering demand for the fundamental understanding of mechanical characteristics of high-speed railway infrastructure,a fullscale multi-functional test platform for high-speed railway track–subgrade system is developed in this paper,and its main functions for investigating the mechanical performance of track–subgrade systems are elaborated with three typical experimental examples.Comprising the full-scale subgrade structure and all the five types of track structures adopted in Chinese high-speed railways,namely the CRTS I,the CRTS II and the CRTS III ballastless tracks,the double-block ballastless track and the ballasted track,the test platform is established strictly according to the construction standard of Chinese high-speed railways.Three kinds of effective loading methods are employed,including the real bogie loading,multi-point loading and the impact loading.Various types of sensors are adopted in different components of the five types of track–subgrade systems to measure the displacement,acceleration,pressure,structural strain and deformation,etc.Utilizing this test platform,both dynamic characteristics and long-term performance evolution of high-speed railway track–subgrade systems can be investigated,being able to satisfy the actual demand for large-scale operation of Chinese high-speed railways.As examples,three typical experimental studies are presented to elucidate the comprehensive functionalities of the full-scale multi-functional test platform for exploring the dynamic performance and its long-term evolution of ballastless track systems and for studying the long-term accumulative settlement of the ballasted track–subgrade system in high-speed railways.Some interesting phenomena and meaningful results are captured by the developed test platform,which provide a useful guidance for the scientific operation and maintenance of high-speed railway infrastructure.
文摘The±200 kV direct current(DC)cables of the Zhoushan Transmission Project were targeted,and crosslinked polyethylene(XLPE)insulation samples were prepared from faulty and spare cables.Samples were tested for oxidation induction period,Fourier transform infrared spectroscopy,differential scanning calorimetry,thermally stimulated depolarisation current,space charge and DC dielectric strength.The evolution of performance parameters was analysed,and the insulation ageing characteristics of onsite operating DC cables were deduced.The results show that compared with spare cables,the carbonyl index of operating cables decreases,the crystallinity increases and DC dielectric strength increases slightly.It is inferred being related to the reduced content of antioxidants and crosslinking by-products and improved molecular chain and crystal microstructure of XLPE insulation.It is suggested that the insulation ageing of high voltage DC XLPE cable is divided into two stages.In the early stage,the secondary crosslinking and recrystallisation processes are dominant,and the thermal and electric effects make the material properties basically stable or even slightly improved.In the middle and later stage,the thermal oxygen reaction is dominant,the microstructure of the material is destroyed,with a large number of macromolecular chains broken and some crystalline regions transformed into amorphous ones,and the insulation properties degraded significantly.
基金support from the One Thousand Young Talents Program under the Recruitment Program of Global Experts,the National Natural Science Foundation of China(NSFC)(21901246,21905278 and 21771179)the Natural Science Foundation of Fujian Province(2019J05158 and 2019J01133).
文摘Developing earth-abundant,highly active,and durable electrocatalysts for the oxygen evolution reaction(OER)is of crucial importance for renewable energy conversion processes.Herein,we fabricated novel flower-like NiFe-layered double hydroxide nanostructures with electron-withdrawing anion intercalation and surface sulfurization via a two-step hydrothermal treatment.Benefiting from the dual-modified electronic structure of the surface active sites of NiFe-LDHs,the as-obtained catalyst showed excellent electrocatalytic activity for the OER,only demanding a low overpotential of 259 mV to achieve 10 mA cm^(-2) in 1.0 M KOH.
基金the financial support from the NSFC(No.21571165)National Science Foundation for Distinguished Young Scholars of China(No.21525101)the NSF of China and Guangxi Province(No.91122032,2014GXNSFFA118003).
文摘The availability of polymorphs of metallic complexes provides an opportunity to reveal the relationship between crystal packing and catalytic activity.Herein,we immobilize two stable concomitant polymorphs(green NiL_(2)-G and red NiL_(2)-R)of mononuclear nickel NiL_(2) on electrodes as heterogeneous oxygen evolution reaction catalysts.Density functional theory calculations reveal that the formation of L_(2)Ni^(Ⅳ)=O from L_(2)Ni^(Ⅲ)-OH is the rate-determining step,whereas R-L_(2)Ni^(Ⅲ)-OH is more stable than G-L_(2)Ni^(Ⅲ)-OH,and forming L_(2)Ni^(Ⅳ)=O from the former has a much lower barrier than from the latter.Consistently,NiL_(2)-R exhibits a lower overpotential(339 mV)than NiL_(2)-G(466 mV)at 10 mA cm^(-2).
基金supported by the Natural Science Foundation of China(22473026)the Natural Science Foundation of Fujian Province(2022J01167,2024J01289)+1 种基金Research Foundation of the Academy of Carbon Neutrality of Fujian Normal University(TZH2022-05)Minjiang Scholar and Startup Fund for High-Level Talent at Fujian Normal University,and Fujian-Taiwan Science and Technology Cooperation Base of Biomedical Materials and Tissue Engineering(2021D039).
文摘Through first-principles structure search calculations,we have discovered a series of hitherto unknown two-dimensional(2D)Janus TMB_(2)O nanomaterials(TM=Fe,Co,Ni,Ru,Rh,Pd,Os,Ir and Pt)featuring a single atomic layer of TM-metallene as one exposed surface resembling the atomic arrangement of Pt(111)surface,which can be well stabilized by a non-metallic BO exposed surface composed of hexagonal rings.Further,by substituting S atoms for O atoms,the TMB_(2)S series can be derived from these nine fascinating TMB_(2)O structures.All eighteen intriguing 2D Janus monolayers exhibit high thermodynamic,dynamical and mechanical stabilities,as well as good conductivity.
基金supported by the Natural Science Research Project of the Anhui Educational Committee(Grant Number 2023AH051183)the Anhui Provincial Natural Science Foundation(Grant Number 2308085QG242)the National Natural Science Foundation of China(Grant Number 52404191).
文摘To better understand the resilience evolution dynamics of urban lifeline systems over extended operational periods,this study introduces a model inspired by the susceptible-infected-recovered(SIR)model,which is traditionally used to simulate population health transitions.By analyzing the mechanisms governing the performance state evolution of urban lifeline systems under disaster scenarios,integrating a disaster scenario model with resilience assessment methodologies,and comprehensively considering three key resilience components—resistance,recovery,and adaptability—we develop a system dynamics resilience-reliability(SDR-R)model.A hypothetical case study is conducted to validate the model's applicability.The results indicate that the interplay of resistance,recovery,and adaptability influences the dynamic evolution of system performance across three states:disability performance,survivability performance,and recovery performance.The model reveals a cyclical pattern in resilience enhancement,with adaptability emerging as a critical determinant.Moreover,the SDR-R model not only simulates urban lifeline performance state evolution under single disaster scenarios but also captures resilience evolution trends over long-term system operations.The case study findings reveal that resilience decreases as disaster severity intensifies,yet positive feedback from adaptability fosters resilience improvement over time.The process of resilience evolution can be divided into four distinct phases:initial impact,adaptive priming,adaptive enhancement,and threshold effect.Notably,resilience dynamics vary significantly across disaster levels.While systems exhibit high resilience under low-level disasters,resilience gradually stabilizes at a high level in medium-and high-level disaster scenarios.However,extreme disasters introduce greater fluctuations in resilience,underscoring the necessity for targeted resilience-enhancing strategies.The insights derived from this study offer methodological guidance for understanding urban lifeline resilience evolution and developing strategies to enhance system robustness.
基金financial support from the National Natural Science Foundation of China(No.21875150 and 22071165)the 111 Project(D20015).
文摘Interstitial oxygen dopants(O_(i))in sulfide nanocrystals are more conducive to charge carrier separation for improving the photocatalytic hydrogen evolution(PHE)performance than substituted oxygen dopants(O_(S)).However,oxygen dopants exist dominantly in the form of OS,rather than O_(i),in oxygen-doped sulfides prepared via traditional methods.
基金sponsored by the National Key Research and Development Program(2021YFE0109800)the National Natural Science Foundation of China(52076126)+1 种基金the Science and Technology Committee of Shanghai Municipality(22010501500)the Key Laboratory of Clean Power Generation and Environmental Protection Technology in Mechanical Industry.
文摘Heterostructure construction has become increasingly recognized as an effective strategy to enhance oxygen evolution reaction(OER)performance due to the exposed active surfaces and improved mass/charge transfer.Inspired by natural plant structures,this study develops a unique moss-like amorphous/crystalline(CoB/CeO_(2))heterojunction.This distinctive moss-like morphology facilitates the formation of staggered sheet structures in the catalyst,providing more active sites and open channels for reaction intermediates and gas release.Benefiting from the hydrophilic properties offered by the moss-like morphology,CoB/CeO_(2) exhibits excellent OER catalytic performance in 1 M KOH,requiring only 247 mV at 100 mA cm^(-2).Physicochemical characterization and mechanistic studies reveal that the close nanoscale features between CoB and CeO_(2) create abundant binary interfaces,optimize the electronic configuration,induce changes in electronic states,and provide abundant defect sites,thereby enhancing charge transfer capabilities.This work presents a new paradigm for the design of efficient and durable OER electrocatalysts.
基金supported by the National Natural Science Foundation of China(Nos.22172093 and 21776167)the Natural Science Foundation of Shandong Province,China(No.ZR2023MB061).
文摘To solve the slow dynamics of catalytic oxygen reaction energy devices,a facile method was developed for the synthesis of methylene alcohol terminated poly(1,4-phenyldiimine)porphyrin cobalt(MPImPorCo),which was synthesized by RuCl_(3) catalyzed redox reaction of meso-5,10,15,20-tetra(4-nitrophenyl)porphyrin cobalt(TNO_(2)-PorCo)and 1,4-phenyldimethanol.M-PImPorCo is a fully conjugated covalent organic framework(COF)with high thermal and chemical stability.COFs with different edge groups were synthesized to compare the effect of different groups(–CH_(2)–OH and–NO_(2))on catalytic bifunctional oxygen reaction activity.C=N as nitrogen-rich environment of M-PImPorCo leads to the protonation process of oxygen catalysis and reduces the energy barrier of adsorption in the oxygen intermediate.C=N and–CH_(2)–OH form an“electron pump”structure to deliver electrons to the Co–N4 site in M-PImPorCo,and theπ–πinteraction between M-PImPorCo and three-dimensional graphene(3D-G)can further enrich the electron cloud density of Co–N_(4) sites.M-PImPorCo/3D-G has remarkable oxygen catalytic performance,with a half-wave potential(E_(1/2))of 0.91 V vs.reversible hydrogen electrode(RHE).M-PImPorCo/3D-G has low potential(Ej=10 is 1.49 V vs.RHE)at a current density of 10 mA·cm^(-2).It exhibits a good bifunctional catalytic performance(potential difference(ΔE)=0.58 V).The smaller charge–discharge band gap of zinc-air batteries(ZABs)and flexible ZABs(F-ZABs)equipped with M-PImPorCo/3D-G suggests the potential for catalytic oxygen reaction bifunctional applications.This work provides a new idea for the synthesis of Schiff-base porphyrin-based COF catalyst and its potential application to oxygen reaction catalytic energy storage devices.
