The Bypass Dual Throat Nozzle(BDTN)is a novel fluidic Thrust Vectoring(TV)nozzle,it switches to TV state by opening the valve in the bypass.To greatly manipulate the BDTN,the dynamic characteristics in the TV starting...The Bypass Dual Throat Nozzle(BDTN)is a novel fluidic Thrust Vectoring(TV)nozzle,it switches to TV state by opening the valve in the bypass.To greatly manipulate the BDTN,the dynamic characteristics in the TV starting process should be analyzed.This paper conducts numerical simulations to grasp the variation processes of performances and the flow field evolution of BDTN and Dual Throat Nozzle(DTN).The dynamic responses of TV starting in typical DTN models are investigated at first.Then,the TV starting processes of BDTN in different Nozzle Pressure Ratio(NPR)conditions are simulated,and the valve opening durations(T)are also considered.Before the expected TV direction is achieved in the DTN,the jet is deflected to the opposite direction at the beginning of the dynamic process,which is called the reverse TV phenomenon.However,this phenomenon disappears in the BDTN.The larger injection width of DTN intensifies unsteady oscillations,and the reverse TV phenomenon is strengthened.In the BDTN,T determines the delay degree of performance variations compared to the static results,which is called hysteresis effect.At NPR=10,the hysteresis affects the final stable performance of BDTN.This study analyses the dynamic characteristics in DTN and BDTN,laying a foundation for further design of nozzles and control strategies.展开更多
Lithium iron phosphate(LFP)offers excellent structural and performance stability derived from the(PO_(4))^(3-)polyanionic structure,which is beneficial for long-term usage.However,this inherent stability also comes al...Lithium iron phosphate(LFP)offers excellent structural and performance stability derived from the(PO_(4))^(3-)polyanionic structure,which is beneficial for long-term usage.However,this inherent stability also comes along with intrinsically poor ionic and electronic conductivities,which have been notoriously plaguing its high-rate performance and broader applications.Here,we present a gas-assisted transient synthesis(GATS,~30 s)of LFP with controllable oxygen vacancies(O_(v))for enhanced rate performance yet without sacrificing structural integrity or cycling stability.Benefited by the ultrafast heating and a higher synthesis temperature,we revealed that the LFP synthesis in GATS followed an interface reaction mechanism(rapid core shrinking)with a low activation energy(E_(a)),thus reducing the synthesis time from~16.5 h in tube furnace heating(TFH,often nuclei-growth mechanism)to merely seconds.The optimized LFP sample demonstrates an 8-fold enhancement in ionic conductivity and a 12-fold increase in electronic conductivity compared to LFP obtained by TFH and attains exceptional cycling stability even at high rates of 10 C,as evidenced by a higher capacity retention of 93.8%(vs.63.6%of commercial LFP)after 1000 cycles.Our strategy offers a kinetic pathway for rapid synthesis and structural engineering of LFP,thus unlocking its potential for broader energy storage applications.展开更多
The growing demand for advanced electrochemical energy storage devices highlights challenges in battery materials,such as limited storage sites,slow ion/electron transport,and structural instability,which collectively...The growing demand for advanced electrochemical energy storage devices highlights challenges in battery materials,such as limited storage sites,slow ion/electron transport,and structural instability,which collectively impede improvements in energy density,rate performance,cycle life,and battery safety.To address these challenges,high-entropy design-a strategy integrating multiple elements through doping,compositional gradients,or alloying-has emerged as a transformative approach to simultaneously enhance thermodynamic stability and unlock synergistic“cocktail effects”in battery materials.By strategically combining elements with tailored atomic-scale interactions,such systems can achieve unprecedented performance between structural robustness and electrochemical activity.However,the design principles and synergistic effects within high-entropy materials(cathodes,electrolytes,anodes)remain poorly understood,complicated by their vast compositional and structural possibilities.In this review,we present a systematic analysis of how high-entropy strategies optimize material properties across three interdependent dimensions:(1)structural engineering(e.g.,surface/interface engineering),(2)physical effects(e.g.,lattice strain and size mismatch),and(3)electronic/chemical interactions(e.g.,valence state modulation and electron delocalization).While entropy alone does not guarantee superior performance,we highlight that rational element selection and configuration design are critical to activating these mechanisms.Importantly,AI-driven framework integrating machine learning with first-principles modeling,can enable data-guided material discovery to decode the complexity of high-entropy systems.This framework systematically deciphers design principles,predicts performance trade-offs,and accelerates the translation of high-entropy materials into practical energy storage solutions.展开更多
Bi is a promising candidate for energy storage materials because of its high volumetric capacity, stability in moisture/air, and facile preparation. In this study, the electrochemical performance of nanosized-Bi-embed...Bi is a promising candidate for energy storage materials because of its high volumetric capacity, stability in moisture/air, and facile preparation. In this study, the electrochemical performance of nanosized-Bi-embedded one-dimensional （1D） carbon nanofibers （Bi/C nanofibers） as anodes for Li-ion batteries （LIBs） and Na-ion batteries （NIBs） was systematically investigated. The Bi/C nanofibers were prepared using a single-nozzle electrospinning method with a specified Bi source followed by carbothermal reduction. Abundant Bi nanoparticles with diameters of approximately 20 nm were homogeneously dispersed and embedded in the 1D carbon nanofibers, as confirmed by structural and morphological characterization. Electrochemical measurements indicate that the Bi/C nanofiber anodes could deliver a long cycle life for LIBs and a preferable rate performance for NIBs. The superior electrochemical performances of the Bi/C nanofiber anodes are attributed to the 1D carbon nanofiber structure and uniform distribution of Bi nanoparticles embedded in the carbon matrix. This unique embedded structure provides a favorable electron carrier and buffering matrix for the effective release of mechanical stress caused by volume change and prevents the aggregation of Bi nanoparticles.展开更多
The fast,sensitive and selective detection of some antibiotics and heavy metal cations in water is highly desirable for environmental protection and human health,but it is still currently challenging.In this work,a ne...The fast,sensitive and selective detection of some antibiotics and heavy metal cations in water is highly desirable for environmental protection and human health,but it is still currently challenging.In this work,a new luminescent Eu(Ⅲ)-based metalorganic framework(MOF),{[(CH_(3))_(2)NH_(2)][Eu(L)2(H_(2)O)_(2)]·xDMF}n(1)[H_(2)L=4,4’-((naphthalene-1,4-dicarbonyl)bis(azanediyl))dibenzoic acid],was solvothermally synthesized.Complex 1 exhibits good water stability and luminescent property and could serve as a bifunctional ratiometric luminescent sensor for fast,sensitive and selective detection of ornidazole(ODZ)and Hg^(2+)in aqueous solution.The corresponding luminescent mechanism has also been discussed.This work indicates that 1 as a promising luminescent material exhibits luminescent quenching behavior for ODZ and luminescent enhancement behavior for Hg^(2+)in H_(2)O,which will promote the practical application of Ln-MOF-based ratiometric luminescent sensors in monitoring antibiotics and metal ions pollutants in the environmental water matrices.展开更多
基金the continued support of Key Laboratory of Inlet and Exhaust system Technology (Nanjing University of Aeronautics and Astronautics), ChinaMinistry of Education, National Science and Technology Major Project of China (Nos. 2017-V-0004-0054, 2019-II-0007-0027, Y2022II-0005-0008)+6 种基金Defense Industrial Technology Development Program of China (No. JCKY2019605D001)Advanced Jet Propulsion Creativity Center of AEAC of China (No. HKCX2020-02-011)China Postdoctoral Science Foundation (No. 2022M721598)Jiangsu Funding Program for Excellent Postdoctoral Talent of China (No. 2022ZB214)the Youth Fund Project of Natural Science Foundation of Jiangsu Province of China (No. BK20230891)the National Natural Science Foundation of China (No. 12332018)Science Center for Gas Turbine Project, China (P2022-B-I-006-001) and some other related foundations
文摘The Bypass Dual Throat Nozzle(BDTN)is a novel fluidic Thrust Vectoring(TV)nozzle,it switches to TV state by opening the valve in the bypass.To greatly manipulate the BDTN,the dynamic characteristics in the TV starting process should be analyzed.This paper conducts numerical simulations to grasp the variation processes of performances and the flow field evolution of BDTN and Dual Throat Nozzle(DTN).The dynamic responses of TV starting in typical DTN models are investigated at first.Then,the TV starting processes of BDTN in different Nozzle Pressure Ratio(NPR)conditions are simulated,and the valve opening durations(T)are also considered.Before the expected TV direction is achieved in the DTN,the jet is deflected to the opposite direction at the beginning of the dynamic process,which is called the reverse TV phenomenon.However,this phenomenon disappears in the BDTN.The larger injection width of DTN intensifies unsteady oscillations,and the reverse TV phenomenon is strengthened.In the BDTN,T determines the delay degree of performance variations compared to the static results,which is called hysteresis effect.At NPR=10,the hysteresis affects the final stable performance of BDTN.This study analyses the dynamic characteristics in DTN and BDTN,laying a foundation for further design of nozzles and control strategies.
基金supported by the Key R&D Program of Hubei Province(No.2024BCB091)the Natural Science Foundation of Hubei Province(No.2022CFA031).
文摘Lithium iron phosphate(LFP)offers excellent structural and performance stability derived from the(PO_(4))^(3-)polyanionic structure,which is beneficial for long-term usage.However,this inherent stability also comes along with intrinsically poor ionic and electronic conductivities,which have been notoriously plaguing its high-rate performance and broader applications.Here,we present a gas-assisted transient synthesis(GATS,~30 s)of LFP with controllable oxygen vacancies(O_(v))for enhanced rate performance yet without sacrificing structural integrity or cycling stability.Benefited by the ultrafast heating and a higher synthesis temperature,we revealed that the LFP synthesis in GATS followed an interface reaction mechanism(rapid core shrinking)with a low activation energy(E_(a)),thus reducing the synthesis time from~16.5 h in tube furnace heating(TFH,often nuclei-growth mechanism)to merely seconds.The optimized LFP sample demonstrates an 8-fold enhancement in ionic conductivity and a 12-fold increase in electronic conductivity compared to LFP obtained by TFH and attains exceptional cycling stability even at high rates of 10 C,as evidenced by a higher capacity retention of 93.8%(vs.63.6%of commercial LFP)after 1000 cycles.Our strategy offers a kinetic pathway for rapid synthesis and structural engineering of LFP,thus unlocking its potential for broader energy storage applications.
基金the National Key R&D Program of China(2021YFA1202300)the Key R&D Program of Hubei Province(2024BCB091)+1 种基金the Interdisciplinary Research Program of HUST(2023JCYJ004)the State Key Laboratory of Advanced Electromagnetic Technology(AET 2025KF003).
文摘The growing demand for advanced electrochemical energy storage devices highlights challenges in battery materials,such as limited storage sites,slow ion/electron transport,and structural instability,which collectively impede improvements in energy density,rate performance,cycle life,and battery safety.To address these challenges,high-entropy design-a strategy integrating multiple elements through doping,compositional gradients,or alloying-has emerged as a transformative approach to simultaneously enhance thermodynamic stability and unlock synergistic“cocktail effects”in battery materials.By strategically combining elements with tailored atomic-scale interactions,such systems can achieve unprecedented performance between structural robustness and electrochemical activity.However,the design principles and synergistic effects within high-entropy materials(cathodes,electrolytes,anodes)remain poorly understood,complicated by their vast compositional and structural possibilities.In this review,we present a systematic analysis of how high-entropy strategies optimize material properties across three interdependent dimensions:(1)structural engineering(e.g.,surface/interface engineering),(2)physical effects(e.g.,lattice strain and size mismatch),and(3)electronic/chemical interactions(e.g.,valence state modulation and electron delocalization).While entropy alone does not guarantee superior performance,we highlight that rational element selection and configuration design are critical to activating these mechanisms.Importantly,AI-driven framework integrating machine learning with first-principles modeling,can enable data-guided material discovery to decode the complexity of high-entropy systems.This framework systematically deciphers design principles,predicts performance trade-offs,and accelerates the translation of high-entropy materials into practical energy storage solutions.
文摘Bi is a promising candidate for energy storage materials because of its high volumetric capacity, stability in moisture/air, and facile preparation. In this study, the electrochemical performance of nanosized-Bi-embedded one-dimensional （1D） carbon nanofibers （Bi/C nanofibers） as anodes for Li-ion batteries （LIBs） and Na-ion batteries （NIBs） was systematically investigated. The Bi/C nanofibers were prepared using a single-nozzle electrospinning method with a specified Bi source followed by carbothermal reduction. Abundant Bi nanoparticles with diameters of approximately 20 nm were homogeneously dispersed and embedded in the 1D carbon nanofibers, as confirmed by structural and morphological characterization. Electrochemical measurements indicate that the Bi/C nanofiber anodes could deliver a long cycle life for LIBs and a preferable rate performance for NIBs. The superior electrochemical performances of the Bi/C nanofiber anodes are attributed to the 1D carbon nanofiber structure and uniform distribution of Bi nanoparticles embedded in the carbon matrix. This unique embedded structure provides a favorable electron carrier and buffering matrix for the effective release of mechanical stress caused by volume change and prevents the aggregation of Bi nanoparticles.
基金financially supported by the National Natural Science Foundation of China(No.21771096)。
文摘The fast,sensitive and selective detection of some antibiotics and heavy metal cations in water is highly desirable for environmental protection and human health,but it is still currently challenging.In this work,a new luminescent Eu(Ⅲ)-based metalorganic framework(MOF),{[(CH_(3))_(2)NH_(2)][Eu(L)2(H_(2)O)_(2)]·xDMF}n(1)[H_(2)L=4,4’-((naphthalene-1,4-dicarbonyl)bis(azanediyl))dibenzoic acid],was solvothermally synthesized.Complex 1 exhibits good water stability and luminescent property and could serve as a bifunctional ratiometric luminescent sensor for fast,sensitive and selective detection of ornidazole(ODZ)and Hg^(2+)in aqueous solution.The corresponding luminescent mechanism has also been discussed.This work indicates that 1 as a promising luminescent material exhibits luminescent quenching behavior for ODZ and luminescent enhancement behavior for Hg^(2+)in H_(2)O,which will promote the practical application of Ln-MOF-based ratiometric luminescent sensors in monitoring antibiotics and metal ions pollutants in the environmental water matrices.
