Micrometer-sized silicon oxide(SiO)anodes encounter challenges in large-scale applications due to significant volume expansion during the alloy/de-alloy process.Herein,an innovative deep eutectic electrolyte derived f...Micrometer-sized silicon oxide(SiO)anodes encounter challenges in large-scale applications due to significant volume expansion during the alloy/de-alloy process.Herein,an innovative deep eutectic electrolyte derived from succinonitrile is introduced to enhance the cycling stability of SiO anodes.Density functional theory calculations validate a robust ion-dipole interaction between lithium ions(Li^(+))and succinonitrile(SN).The cosolvent fluoroethylene carbonate(FEC)optimizes the Li^(+)solvation structure in the SN-based electrolyte with its weakly solvating ability.Molecular dynamics simulations investigate the regulating mechanism of ion-dipole and cation-anion interaction.The unique Li^(+)solvation structure,enriched with FEC and TFSI^(-),facilitates the formation of an inorganic-organic composite solid electrolyte interphase on SiO anodes.Micro-CT further detects the inhibiting effect on the SiO volume expansion.As a result,the SiO|LiCoO_(2) full cells exhibit excellent electrochemical performance in deep eutectic-based electrolytes.This work presents an effective strategy for extending the cycle life of SiO anodes by designing a new SN-based deep eutectic electrolyte.展开更多
The supercritical CO_(2)(sCO_(2))power cycle could improve efficiencies for a wide range of thermal power plants.The sCO_(2)turbine generator plays an important role in the sCO_(2)power cycle by directly converting th...The supercritical CO_(2)(sCO_(2))power cycle could improve efficiencies for a wide range of thermal power plants.The sCO_(2)turbine generator plays an important role in the sCO_(2)power cycle by directly converting thermal energy into mechanical work and electric power.The operation of the generator encounters challenges,including high temperature,high pressure,high rotational speed,and other engineering problems,such as leakage.Experimental studies of sCO_(2)turbines are insufficient because of the significant difficulties in turbine manufacturing and system construction.Unlike most experimental investigations that primarily focus on 100 kW‐or MW‐scale power generation systems,we consider,for the first time,a small‐scale power generator using sCO_(2).A partial admission axial turbine was designed and manufactured with a rated rotational speed of 40,000 rpm,and a CO_(2)transcritical power cycle test loop was constructed to validate the performance of our manufactured generator.A resistant gas was proposed in the constructed turbine expander to solve the leakage issue.Both dynamic and steady performances were investigated.The results indicated that a peak electric power of 11.55 kW was achieved at 29,369 rpm.The maximum total efficiency of the turbo‐generator was 58.98%,which was affected by both the turbine rotational speed and pressure ratio,according to the proposed performance map.展开更多
A manned mission to Mars represents a crucial milestone for humanity in exploring deep space,understanding the origins of life and advancing interstellar civilization[1].In 2024,the Chinese government publicly announc...A manned mission to Mars represents a crucial milestone for humanity in exploring deep space,understanding the origins of life and advancing interstellar civilization[1].In 2024,the Chinese government publicly announced its plan to implement the Tianwen-3 mission,which focuses on Mars sample return,laying the foundation for future manned Mars missions[2].展开更多
Employing a CO_(2)power generation system to recover waste heat from engines can reduce fuel consumption and CO_(2)emissions by producing additional electric power.Nevertheless,the fluctuation in engine operating cond...Employing a CO_(2)power generation system to recover waste heat from engines can reduce fuel consumption and CO_(2)emissions by producing additional electric power.Nevertheless,the fluctuation in engine operating conditions would cause variations in waste heat sources and affect system performances largely.Hence,an experimental performance test at various engine conditions was implemented by the construction of a small-scale(10 kW)CO_(2)power generation system.Key components,including the turbine expander and printed circuit heat exchanger,were specifically designed and constructed.The steady-state and transient performances of critical components and the integrated system were carried out.Experimental results of the turbine expander at varying engine conditions revealed the potential for long-term and stable operation under dynamic mass flow rate,inlet temperature,and pressure ratio.The maximum total generation power and efficiency reached 11.55 kW and 58.92%.The printed circuit heat exchanger used to exploit engine exhaust gas showed satisfactory performances in balancing the trade-off between heat transfer and pressure drop.The total pressure drop of engine exhaust gas was lower than 4 kPa determined by both exhaust mass flow and temperature,considering all the variable engine conditions.Despite that a performance penalty was observed at the off-design operation of the integrated system because of the decrease in the waste heat input,the maximum net power and thermal efficiency reached 10.57 kW and 6.59%,respectively,at the engine condition of 1100 rpm,1200 N m,with a relative improvement of 6.3%in engine brake thermal efficiency.展开更多
The CO_(2)-based combined cooling and power(CCP)system is regarded as a highly promising alternative for waste heat recovery in refrigerated trucks,owing to its environmental advantages and multienergy output.The CCP ...The CO_(2)-based combined cooling and power(CCP)system is regarded as a highly promising alternative for waste heat recovery in refrigerated trucks,owing to its environmental advantages and multienergy output.The CCP system implemented in refrigerated trucks is more intricate than conventional waste heat recovery systems.It not only produces energy to satisfy demand via waste heat recovery but also incorporates refrigeration capabilities,substituting the standalone refrigeration unit to sustain low temperatures in refrigerated trucks.This coupling of power and refrigeration subcycles significantly increases the complexity of system control and the requirements for stability.Current research primarily focuses on the steady-state performance of CCP systems,neglecting the impact of load variations on the system’s dynamic response in real operating conditions,thereby limiting a comprehensive assessment of operational performance under complex scenarios.This study proposes a hybrid control strategy based on deep deterministic policy gradient deep reinforcement learning and conducts dynamic simulations to comprehensively evaluate the energy efficiency performance of the CCP system.The results show that under the China Heavy-Duty Commercial Vehicle Test Cycle conditions,this strategy reduces fuel consumption by 6.63%per 100 km while ensuring that the CCP system remains within safety constraints throughout the entire operation.These findings provide important insights for the application of CCP systems in the cold chain transportation sector.展开更多
The development of electric vehicles(EVs)exhibits rapid and remarkable progress nowadays,serving as a crucial route to accomplish the target of mitigating greenhouse gas emissions.As an integral part of the thermal ma...The development of electric vehicles(EVs)exhibits rapid and remarkable progress nowadays,serving as a crucial route to accomplish the target of mitigating greenhouse gas emissions.As an integral part of the thermal manage-ment system oriented toward electric vehicles,the heat pump air conditioning system for electric vehicles is the result of a comprehensive choice that trades off the cooling and heating performance,environmental performance and economic cost.Particularly,different regions around the world suffer varying cooling and heating challenges due to the complicated climatic characteristics.Thus the most suitable refrigerant and system cycle structure may differ.This paper focuses on evaluating both the refrigerants and cycle structures to screen the most suitable choice.According to the climate conditions of different cities,the annual energy consumption,life cycle climate perfor-mance,and economic cost of the basic system(Base),two-stage compression system(TSC,IC),and vapor injection(VI)system with CO_(2),R134a,and R1234yf refrigerants respectively,are quantitatively analyzed and evaluated.Subse-quently,through comparative analysis,a comprehensive selection map for heat pump systems in electric vehicles worldwide is developed and the most suitable heat pump air conditioning system for each cites is determined.The results can provide a selection reference and decision-making for the air conditioning system of electric vehicles from regional considerations.It was found that the CO_(2) HPACVI was recommended for cold regions to meet both envi-ronmental and economic requirements.In warm region,the R1234yf HPAC_(Base) system was recommended to be used.For regions transitioning from cold to warm climates,the R1234yf HPAC_(VI) system was suggested.In hot region,the R1234yf AC system was recommended.展开更多
Thermal-integrated pumped thermal electricity storage(TI-PTES)could realize efficient energy storage for fluctu-ating and intermittent renewable energy.However,the boundary conditions of TI-PTES may frequently change ...Thermal-integrated pumped thermal electricity storage(TI-PTES)could realize efficient energy storage for fluctu-ating and intermittent renewable energy.However,the boundary conditions of TI-PTES may frequently change with the variation of times and seasons,which causes a tremendous deterioration to the operating performance.To realize efficient and flexible energy storage in operating conditions,a novel composition-adjustable TI-PTES is pro-posed,and the operating performance is investigated and compared with composition-fixed TI-PTES.Simulation results show that,compared to composition-fixed TI-PTES,the energy storage efficiency of TI-PTES could be enhanced by the absolute value of 4.4–18.3%by introducing composition adjustment method under various boundary con-ditions.Besides,tuning sub-system composition could simultaneously adjust the capacities of power input,heat storage and power output,realizing a more flexible operating range for TI-PTES.A case study for an isolated energy community shows that composition-adjustable TI-PTES could realize 100%conversion of off-peak electric energy and reduce daily investment by 35.6%compared with composition-fixed TI-PTES.展开更多
The issue of climate change is among the most difficult environmental problems faced by human beings[1]and affects all social aspects of human life.In 2015,the Paris Agreement set the goal of reducing global greenhous...The issue of climate change is among the most difficult environmental problems faced by human beings[1]and affects all social aspects of human life.In 2015,the Paris Agreement set the goal of reducing global greenhouse gas(GHG)emissions to limit the global temperature increase to 2℃and even further to 1.5℃[2].展开更多
Casi2b/C2ci is a newly identified class 2 CRISPR endonuclease that was recently engineered for targeted genome editing in mammals and rice.To explore the potential applications of the CRISPR-Casi2b system in the dicot...Casi2b/C2ci is a newly identified class 2 CRISPR endonuclease that was recently engineered for targeted genome editing in mammals and rice.To explore the potential applications of the CRISPR-Casi2b system in the dicot Arabidopsis thaliana,we selected BvCasi2b and BhCasi2b v4 for analysis.We successfully used both endonucleases to induce mutations,perform multiplex genome editing,and create large deletions at multiple loci.No significant mutations were detected at potential off-target sites.Analysis of the insertion/deletion frequencies and patterns of mutants generated via targeted gene mutagenesis highlighted the potential utility of CRISPRCasi2b systems for genome editing in Arabidopsis.展开更多
基金supported by the National Natural Science Foundation of China(22279026)the National Key Research and Development Program of China(2022YFE0138900)+2 种基金the Young Elite Scientist sponsorship program by CAST(no.20200148)the Natural Science Funds of Heilongjiang Province(YQ2021B003)the Fundamental Research Funds for the Central Universities(grant no.HIT.OCEF.2022017).
文摘Micrometer-sized silicon oxide(SiO)anodes encounter challenges in large-scale applications due to significant volume expansion during the alloy/de-alloy process.Herein,an innovative deep eutectic electrolyte derived from succinonitrile is introduced to enhance the cycling stability of SiO anodes.Density functional theory calculations validate a robust ion-dipole interaction between lithium ions(Li^(+))and succinonitrile(SN).The cosolvent fluoroethylene carbonate(FEC)optimizes the Li^(+)solvation structure in the SN-based electrolyte with its weakly solvating ability.Molecular dynamics simulations investigate the regulating mechanism of ion-dipole and cation-anion interaction.The unique Li^(+)solvation structure,enriched with FEC and TFSI^(-),facilitates the formation of an inorganic-organic composite solid electrolyte interphase on SiO anodes.Micro-CT further detects the inhibiting effect on the SiO volume expansion.As a result,the SiO|LiCoO_(2) full cells exhibit excellent electrochemical performance in deep eutectic-based electrolytes.This work presents an effective strategy for extending the cycle life of SiO anodes by designing a new SN-based deep eutectic electrolyte.
基金National Science Fund for Excellent Young Scholars,Grant/Award Number:52022066。
文摘The supercritical CO_(2)(sCO_(2))power cycle could improve efficiencies for a wide range of thermal power plants.The sCO_(2)turbine generator plays an important role in the sCO_(2)power cycle by directly converting thermal energy into mechanical work and electric power.The operation of the generator encounters challenges,including high temperature,high pressure,high rotational speed,and other engineering problems,such as leakage.Experimental studies of sCO_(2)turbines are insufficient because of the significant difficulties in turbine manufacturing and system construction.Unlike most experimental investigations that primarily focus on 100 kW‐or MW‐scale power generation systems,we consider,for the first time,a small‐scale power generator using sCO_(2).A partial admission axial turbine was designed and manufactured with a rated rotational speed of 40,000 rpm,and a CO_(2)transcritical power cycle test loop was constructed to validate the performance of our manufactured generator.A resistant gas was proposed in the constructed turbine expander to solve the leakage issue.Both dynamic and steady performances were investigated.The results indicated that a peak electric power of 11.55 kW was achieved at 29,369 rpm.The maximum total efficiency of the turbo‐generator was 58.98%,which was affected by both the turbine rotational speed and pressure ratio,according to the proposed performance map.
基金supported by the USTC Research Funds of the Double First-Class Initiative(YD2090002008)the Fundamental Research Funds for the Central Universities(WK2090000032).
基金supported by the Youth Innovation Promotion Association Chinese Academy of Sciences(2022463)the National Natural Science Foundation of China(52425602).
文摘A manned mission to Mars represents a crucial milestone for humanity in exploring deep space,understanding the origins of life and advancing interstellar civilization[1].In 2024,the Chinese government publicly announced its plan to implement the Tianwen-3 mission,which focuses on Mars sample return,laying the foundation for future manned Mars missions[2].
文摘Employing a CO_(2)power generation system to recover waste heat from engines can reduce fuel consumption and CO_(2)emissions by producing additional electric power.Nevertheless,the fluctuation in engine operating conditions would cause variations in waste heat sources and affect system performances largely.Hence,an experimental performance test at various engine conditions was implemented by the construction of a small-scale(10 kW)CO_(2)power generation system.Key components,including the turbine expander and printed circuit heat exchanger,were specifically designed and constructed.The steady-state and transient performances of critical components and the integrated system were carried out.Experimental results of the turbine expander at varying engine conditions revealed the potential for long-term and stable operation under dynamic mass flow rate,inlet temperature,and pressure ratio.The maximum total generation power and efficiency reached 11.55 kW and 58.92%.The printed circuit heat exchanger used to exploit engine exhaust gas showed satisfactory performances in balancing the trade-off between heat transfer and pressure drop.The total pressure drop of engine exhaust gas was lower than 4 kPa determined by both exhaust mass flow and temperature,considering all the variable engine conditions.Despite that a performance penalty was observed at the off-design operation of the integrated system because of the decrease in the waste heat input,the maximum net power and thermal efficiency reached 10.57 kW and 6.59%,respectively,at the engine condition of 1100 rpm,1200 N m,with a relative improvement of 6.3%in engine brake thermal efficiency.
基金Guangxi Science and Technol-ogy Major Program(AA24206013)the National Science Found for Excellent Young Scholars(No.52022066)+1 种基金the Youth Innovation Pro-motion Association of Chinese Academy of Sciences(Grant No 2022463)the Research Center for Multi-Energy Complementation and Conversion.
文摘The CO_(2)-based combined cooling and power(CCP)system is regarded as a highly promising alternative for waste heat recovery in refrigerated trucks,owing to its environmental advantages and multienergy output.The CCP system implemented in refrigerated trucks is more intricate than conventional waste heat recovery systems.It not only produces energy to satisfy demand via waste heat recovery but also incorporates refrigeration capabilities,substituting the standalone refrigeration unit to sustain low temperatures in refrigerated trucks.This coupling of power and refrigeration subcycles significantly increases the complexity of system control and the requirements for stability.Current research primarily focuses on the steady-state performance of CCP systems,neglecting the impact of load variations on the system’s dynamic response in real operating conditions,thereby limiting a comprehensive assessment of operational performance under complex scenarios.This study proposes a hybrid control strategy based on deep deterministic policy gradient deep reinforcement learning and conducts dynamic simulations to comprehensively evaluate the energy efficiency performance of the CCP system.The results show that under the China Heavy-Duty Commercial Vehicle Test Cycle conditions,this strategy reduces fuel consumption by 6.63%per 100 km while ensuring that the CCP system remains within safety constraints throughout the entire operation.These findings provide important insights for the application of CCP systems in the cold chain transportation sector.
基金the Key Collaborative Research Program of the Alliance of International Science Organizations(Grant No.ANSO-CR-KP-2022-04)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2022463).
文摘The development of electric vehicles(EVs)exhibits rapid and remarkable progress nowadays,serving as a crucial route to accomplish the target of mitigating greenhouse gas emissions.As an integral part of the thermal manage-ment system oriented toward electric vehicles,the heat pump air conditioning system for electric vehicles is the result of a comprehensive choice that trades off the cooling and heating performance,environmental performance and economic cost.Particularly,different regions around the world suffer varying cooling and heating challenges due to the complicated climatic characteristics.Thus the most suitable refrigerant and system cycle structure may differ.This paper focuses on evaluating both the refrigerants and cycle structures to screen the most suitable choice.According to the climate conditions of different cities,the annual energy consumption,life cycle climate perfor-mance,and economic cost of the basic system(Base),two-stage compression system(TSC,IC),and vapor injection(VI)system with CO_(2),R134a,and R1234yf refrigerants respectively,are quantitatively analyzed and evaluated.Subse-quently,through comparative analysis,a comprehensive selection map for heat pump systems in electric vehicles worldwide is developed and the most suitable heat pump air conditioning system for each cites is determined.The results can provide a selection reference and decision-making for the air conditioning system of electric vehicles from regional considerations.It was found that the CO_(2) HPACVI was recommended for cold regions to meet both envi-ronmental and economic requirements.In warm region,the R1234yf HPAC_(Base) system was recommended to be used.For regions transitioning from cold to warm climates,the R1234yf HPAC_(VI) system was suggested.In hot region,the R1234yf AC system was recommended.
基金funding provided by University of Science and Technology of China.This work is financially supported by the Students’Innovation and Entrepreneurship Foundation of USTC(Grant No.CY2022G35)Youth Innovation Promotion Association CAS(Grant No.2022463)the USTC Institute for Carbon Neutrality and Joint research center for multi-energy complementation and conversion.
文摘Thermal-integrated pumped thermal electricity storage(TI-PTES)could realize efficient energy storage for fluctu-ating and intermittent renewable energy.However,the boundary conditions of TI-PTES may frequently change with the variation of times and seasons,which causes a tremendous deterioration to the operating performance.To realize efficient and flexible energy storage in operating conditions,a novel composition-adjustable TI-PTES is pro-posed,and the operating performance is investigated and compared with composition-fixed TI-PTES.Simulation results show that,compared to composition-fixed TI-PTES,the energy storage efficiency of TI-PTES could be enhanced by the absolute value of 4.4–18.3%by introducing composition adjustment method under various boundary con-ditions.Besides,tuning sub-system composition could simultaneously adjust the capacities of power input,heat storage and power output,realizing a more flexible operating range for TI-PTES.A case study for an isolated energy community shows that composition-adjustable TI-PTES could realize 100%conversion of off-peak electric energy and reduce daily investment by 35.6%compared with composition-fixed TI-PTES.
基金supported by the National Key Research and Development Program of China(2021YFF0306801)National Science Fund for Excellent Young Scholars(52022066)。
文摘The issue of climate change is among the most difficult environmental problems faced by human beings[1]and affects all social aspects of human life.In 2015,the Paris Agreement set the goal of reducing global greenhouse gas(GHG)emissions to limit the global temperature increase to 2℃and even further to 1.5℃[2].
基金This work was supported by the National Natural Science Foundation of China(31570190,31800224)the Science Technology and Innovation Committee of Shenzhen Municipality(JCYJ20170303154319837,JCYJ20170412155447658)+1 种基金the Natural Science Foundation of Hebei Province(12017208087)the Science and Technology Research Program for Colleges and Universities in Hebei Province(QN2018149).
文摘Casi2b/C2ci is a newly identified class 2 CRISPR endonuclease that was recently engineered for targeted genome editing in mammals and rice.To explore the potential applications of the CRISPR-Casi2b system in the dicot Arabidopsis thaliana,we selected BvCasi2b and BhCasi2b v4 for analysis.We successfully used both endonucleases to induce mutations,perform multiplex genome editing,and create large deletions at multiple loci.No significant mutations were detected at potential off-target sites.Analysis of the insertion/deletion frequencies and patterns of mutants generated via targeted gene mutagenesis highlighted the potential utility of CRISPRCasi2b systems for genome editing in Arabidopsis.
