Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures....Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.展开更多
An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipo...An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipole layer at the internal Helmholtz electrical double layers(HEDLs) under the preferential adsorption function of formate on Zn surface,reducing the occurrence of side reactions at phase interface.Meanwhile,free formate in HEDLs regulates the Zn^(2+) solvation sheath structure to accelerate the desolvation,transference,and deposition kinetics of Zn^(2+).Besides,the hydrolysis reaction of zinc formate increases the hydrogen evolution overpotential,inhibiting the thermodynamic tendency of hydrogen evolution.Consequently,it presents stable cycle for more than 2400 h at 5 mA cm^(-2),as well as an average Coulombic efficiency of 99.8% at 1 A g^(-1) after 800 cycles in the Zn‖VO_(2) full cell.The interphase engineering strategy zinc anode by organic small molecular brings new possibility towards high-performance aqueous zinc-ion batteries.展开更多
A-form DNA is one of the biologically active double helical structure.The study of A-DNA structure has an extensive application for developing the field of DNA packaging in biotechnology.In aqueous solution,the A-DNA ...A-form DNA is one of the biologically active double helical structure.The study of A-DNA structure has an extensive application for developing the field of DNA packaging in biotechnology.In aqueous solution,the A-DNA structure will have a free transformation,the A-DNA structure will be translated into B-form structure with the evolution of time,and eventually stabilized in the B-DNA structure.To explore the stability function of the bivalent metal ions on the A-DNA structure,a series of molecular dynamics simulations have been performed on the A-DNA of sequence(CCCGGCCGGG).The results show that bivalent metal ions(Mg^(2+),Zn^(2+),Ca^(2+))generate a great effect on the structural stability of A-DNA in the environment of high concentration.As the interaction between metal ions and electronegative DNA chains,the stability of A-DNA in solution is gradually improved with the increasing solution concentration of ions.In metal salt solution with high concentration,metal ions can be easily distributed in the solvation shells around the phosphate groups and further lead to the formation of shorter and more compact DNA structure.Also,under the condition of the same concentration and valency of the metal ions,the stability of A-DNA structure is different.The calculations indicate that the structure of A-DNA in CaCl_(2)solution is less stable than in MgCl_(2)and ZnCl_(2)solution.展开更多
Enhancing the cut-off voltage of high-nickel layered oxide cathodes is an efficient way to obtain higher energy density of lithiummetal batteries(LMBs).However,the phase transition of the cathode materials and the unc...Enhancing the cut-off voltage of high-nickel layered oxide cathodes is an efficient way to obtain higher energy density of lithiummetal batteries(LMBs).However,the phase transition of the cathode materials and the uncontrolled decomposition of the electrolytes at high voltage can lead to irreversible dissolution of transition metal ions,which might cause the crossover effects on the lithium metal anodes.Nonetheless,the mechanism and electrolyte dependence of the crossover effects for Li metal anodes are still unclear.Herein,we investigate the crossover effects between LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)and Li-metal anode in two electrolyte systems.For ether-based electrolyte,its poor oxidation stability results in massive dissolution of transition metal ions,leading to dendrite growth on anode and rapid cells failure.Conversely,ester-based electrolyte exhibits good electrochemical performances at 4.5 V with little crossover effect.This study provides an idea for electrolyte systems selection for high-voltage LMBs,and verifies that the crossover effect should not be neglected in LMBs.展开更多
With unlimited topological modes in mathematics,the fractional orbital angular momentum(FOAM)demonstrates the potential to infinitely increase the channel capacity in acoustic-vortex(AV)communications.However,the accu...With unlimited topological modes in mathematics,the fractional orbital angular momentum(FOAM)demonstrates the potential to infinitely increase the channel capacity in acoustic-vortex(AV)communications.However,the accuracy and stability of FOAM recognition are still limited by the nonorthogonality and poor anti-interference of fractional AV beams.The popular machine learning,widely used in optics based on large datasets of images,does not work in acoustics because of the huge engineering of the 2-dimensional point-by-point measurement.Here,we report a strategy of phase-dislocation-mediated high-dimensional fractional AV communication based on pair-FOAM multiplexing,circular sparse sampling,and machine learning.The unique phase dislocation corresponding to the topological charge provides important physical guidance to recognize FOAMs and reduce sampling points from theory to practice.A straightforward convolutional neural network considering turbulence and misalignment is further constructed to achieve the stable and accurate communication without involving experimental data.We experimentally present that the 32-point dual-ring sampling can realize the 10-bit information transmission in a limited topological charge scope from±0.6 to±2.4 with the FOAM resolution of 0.2,which greatly reduce the divergence in AV communications.The infinitely expanded channel capacity is further verified by the improved FOAM resolution of 0.025.Compared with other milestone works,our strategy reaches 3-fold OAM utilization,4-fold information level,and 5-fold OAM resolution.Because of the extra advantages of high dimension,high speed,and low divergence,this technology may shed light on the next-generation AV communication.展开更多
This short note provides a new and simple proof of the convergence rate for the Peng’s law of large numbers under sublinear expectations,which improves the results presented by Song[15]and Fang et al.[3].
A new Hartman-Wintner-type law of the iterated logarithm for independent random variables with mean-uncertainty under sublinear expectations is established by the martingale analogue of the Kolmogorov law of the itera...A new Hartman-Wintner-type law of the iterated logarithm for independent random variables with mean-uncertainty under sublinear expectations is established by the martingale analogue of the Kolmogorov law of the iterated logarithm in classical probability theory.展开更多
With the rapid development of remote-sensing technology and the increasing number of Earth observation satellites,the volume of image datasets is growing exponentially.The management of big Earth data is also becoming...With the rapid development of remote-sensing technology and the increasing number of Earth observation satellites,the volume of image datasets is growing exponentially.The management of big Earth data is also becoming increasingly complex and difficult,with the result that it can be hard for users to access the imagery that they are interested in quickly,efficiently and intelligently.To address these challenges,this paper proposes a remote-sensing image-retrieval model based on an ensemble neural networks.This model can make full use of existing training data to improve the efficiency and accuracy of the initial retrieval of remotesensing images and keep model simple.The retrieval of aerial images using the proposed model is compared with the results obtained using ten individual neural networks and two ensemble neural networks and the results show that the proposed approach has a high degree of precision.In addition,the coverage rate and mean precision show a dramatic improvement of more than 40%compared with existing methods based on normal way.And,the coverage ratio gets 86%for the top 10 return results.展开更多
基金supported by the National Natural Science Foundation of China (grant No.52072322)the Department of Science and Technology of Sichuan Province (CN) (grant no.23GJHZ0147,23ZDYF0262,2022YFG0294)Research and Innovation Fund for Graduate Students of Southwest Petroleum University (No.:2022KYCX111)。
文摘Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.
基金supported by the National Natural Science Foundation of China (Grant Nos. 52072322, 51604250)the Sichuan Science and Technology Program, China (Grant Nos. 2022YFG0294, 2019-GH02-00052-HZ)the Undergraduate Innovation and Entrepreneurship Program (S202210615189)。
文摘An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipole layer at the internal Helmholtz electrical double layers(HEDLs) under the preferential adsorption function of formate on Zn surface,reducing the occurrence of side reactions at phase interface.Meanwhile,free formate in HEDLs regulates the Zn^(2+) solvation sheath structure to accelerate the desolvation,transference,and deposition kinetics of Zn^(2+).Besides,the hydrolysis reaction of zinc formate increases the hydrogen evolution overpotential,inhibiting the thermodynamic tendency of hydrogen evolution.Consequently,it presents stable cycle for more than 2400 h at 5 mA cm^(-2),as well as an average Coulombic efficiency of 99.8% at 1 A g^(-1) after 800 cycles in the Zn‖VO_(2) full cell.The interphase engineering strategy zinc anode by organic small molecular brings new possibility towards high-performance aqueous zinc-ion batteries.
基金supported by the National Natural Science Foundation of China(Grant No.11564015)the Foundation of Educational Committee of Jiangxi Province,China(Grant No.GJJ211112)the Fund for Distinguished Young Scholars of Jiangxi Science&Technology Normal University(Grant No.2015QN-BJRC002)。
文摘A-form DNA is one of the biologically active double helical structure.The study of A-DNA structure has an extensive application for developing the field of DNA packaging in biotechnology.In aqueous solution,the A-DNA structure will have a free transformation,the A-DNA structure will be translated into B-form structure with the evolution of time,and eventually stabilized in the B-DNA structure.To explore the stability function of the bivalent metal ions on the A-DNA structure,a series of molecular dynamics simulations have been performed on the A-DNA of sequence(CCCGGCCGGG).The results show that bivalent metal ions(Mg^(2+),Zn^(2+),Ca^(2+))generate a great effect on the structural stability of A-DNA in the environment of high concentration.As the interaction between metal ions and electronegative DNA chains,the stability of A-DNA in solution is gradually improved with the increasing solution concentration of ions.In metal salt solution with high concentration,metal ions can be easily distributed in the solvation shells around the phosphate groups and further lead to the formation of shorter and more compact DNA structure.Also,under the condition of the same concentration and valency of the metal ions,the stability of A-DNA structure is different.The calculations indicate that the structure of A-DNA in CaCl_(2)solution is less stable than in MgCl_(2)and ZnCl_(2)solution.
基金supported by the National Natural Science Foundation of China(Nos.51902304,52072358,U21A2082,22279127,and 52225105).
文摘Enhancing the cut-off voltage of high-nickel layered oxide cathodes is an efficient way to obtain higher energy density of lithiummetal batteries(LMBs).However,the phase transition of the cathode materials and the uncontrolled decomposition of the electrolytes at high voltage can lead to irreversible dissolution of transition metal ions,which might cause the crossover effects on the lithium metal anodes.Nonetheless,the mechanism and electrolyte dependence of the crossover effects for Li metal anodes are still unclear.Herein,we investigate the crossover effects between LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)and Li-metal anode in two electrolyte systems.For ether-based electrolyte,its poor oxidation stability results in massive dissolution of transition metal ions,leading to dendrite growth on anode and rapid cells failure.Conversely,ester-based electrolyte exhibits good electrochemical performances at 4.5 V with little crossover effect.This study provides an idea for electrolyte systems selection for high-voltage LMBs,and verifies that the crossover effect should not be neglected in LMBs.
基金the National Natural Science Foundation of China(grant nos.11934009,11974187,12174198,12227808,62025501,31971376,and 92150301)National Key R&D Program of China(2022YFC3401100)+1 种基金the Natural Science Foundation of Jiangsu Province(no.BE2022814)the Qing Lan Project of Jiangsu Province,China.
文摘With unlimited topological modes in mathematics,the fractional orbital angular momentum(FOAM)demonstrates the potential to infinitely increase the channel capacity in acoustic-vortex(AV)communications.However,the accuracy and stability of FOAM recognition are still limited by the nonorthogonality and poor anti-interference of fractional AV beams.The popular machine learning,widely used in optics based on large datasets of images,does not work in acoustics because of the huge engineering of the 2-dimensional point-by-point measurement.Here,we report a strategy of phase-dislocation-mediated high-dimensional fractional AV communication based on pair-FOAM multiplexing,circular sparse sampling,and machine learning.The unique phase dislocation corresponding to the topological charge provides important physical guidance to recognize FOAMs and reduce sampling points from theory to practice.A straightforward convolutional neural network considering turbulence and misalignment is further constructed to achieve the stable and accurate communication without involving experimental data.We experimentally present that the 32-point dual-ring sampling can realize the 10-bit information transmission in a limited topological charge scope from±0.6 to±2.4 with the FOAM resolution of 0.2,which greatly reduce the divergence in AV communications.The infinitely expanded channel capacity is further verified by the improved FOAM resolution of 0.025.Compared with other milestone works,our strategy reaches 3-fold OAM utilization,4-fold information level,and 5-fold OAM resolution.Because of the extra advantages of high dimension,high speed,and low divergence,this technology may shed light on the next-generation AV communication.
基金This project is supported by National Key R&D Program of China(Grant No.2018YFA0703900)National Natural Science Foundation of China(Grant Nos.11601281,11671231).
文摘This short note provides a new and simple proof of the convergence rate for the Peng’s law of large numbers under sublinear expectations,which improves the results presented by Song[15]and Fang et al.[3].
基金supported by NSF of Shandong Province(Grant No.ZR2021MA018)National Key R&D Program of China(Grant No.2018YFA0703900)+1 种基金NSF of China(Grant No.11601281)the Young Scholars Program of Shandong University.
文摘A new Hartman-Wintner-type law of the iterated logarithm for independent random variables with mean-uncertainty under sublinear expectations is established by the martingale analogue of the Kolmogorov law of the iterated logarithm in classical probability theory.
基金This work was supported by the National Natural Science Funds of China[41501116].
文摘With the rapid development of remote-sensing technology and the increasing number of Earth observation satellites,the volume of image datasets is growing exponentially.The management of big Earth data is also becoming increasingly complex and difficult,with the result that it can be hard for users to access the imagery that they are interested in quickly,efficiently and intelligently.To address these challenges,this paper proposes a remote-sensing image-retrieval model based on an ensemble neural networks.This model can make full use of existing training data to improve the efficiency and accuracy of the initial retrieval of remotesensing images and keep model simple.The retrieval of aerial images using the proposed model is compared with the results obtained using ten individual neural networks and two ensemble neural networks and the results show that the proposed approach has a high degree of precision.In addition,the coverage rate and mean precision show a dramatic improvement of more than 40%compared with existing methods based on normal way.And,the coverage ratio gets 86%for the top 10 return results.
