Owing to anionic redox,cathode materials containing layered Li-rich Mn-based oxides(LLOs)are promising for the development of next-generation lithium-ion batteries(LIBs)with a large energy density(~500–600 Wh·kg...Owing to anionic redox,cathode materials containing layered Li-rich Mn-based oxides(LLOs)are promising for the development of next-generation lithium-ion batteries(LIBs)with a large energy density(~500–600 Wh·kg^(−1)).However,these LLOs are easily degraded during cycling,which limits their lifespan.So far,the degradation mechanism is still under debate.Herein,LLOs are post-treated through implantation with energetic Ti ion flux(Ti-LLO),which modifies the structure of LLOs both at the surface and within the bulk.Unlike the dominant R3m phase(73.24%)observed in LLOs,the phase structure of Ti-LLO is altered,with Li-rich C2/m accounting for 67.72%in the bulk,alongside the formation of a thin(approximately 2 nm),uniform,and continuous Li-Ti-O spinel layer at the surface.Apart from phase structure changes,chemical valence states of transition metals and O,as well as their evolution,are analyzed and compared to charge transport kinetics to elucidate their contributions to the enhanced discharge capacity in Ti-LLOs.Besides,the role of the Li-Ti-O spinel layer at the surface in providing anticorrosion protection at the interface of LLOs/electrolyte during cycling is evaluated.As a result,we demonstrate that a superhigh discharge capacity(335.3 mAh·g^(−1))at 0.1 C can be achieved,along with prolonged cycling stability(showing capacity retention of approximately 80%after 500 cycles at 1 C)through these modifications.Moreover,we confirmed the universality of the strategy by implanting other ions,which offers practical strategies for achieving high performance in LLO cathode materials through thermodynamics and kinetics pathways.展开更多
High-power direct current fast charging(DC-HPC),particularly for megawatt-level charging currents(≥1000 A),is expected to significantly reduce charging time and improve electric vehicle durability,despite the risk of...High-power direct current fast charging(DC-HPC),particularly for megawatt-level charging currents(≥1000 A),is expected to significantly reduce charging time and improve electric vehicle durability,despite the risk of instantaneous thermal shocks.Conventional cooling methods,which separately transmit current and heat,struggle to achieve both flexible maneuverability and high-efficiency cooling.In this study,we present a synergetic cooling and transmission strategy using a gallium-based liquid metal flexible charging connector(LMFCC),which efficiently dissipates ultra-high heat flux while simultaneously carrying superhigh current.The LMFCC exhibits exceptional flexible operability(bending radius of 2 cm)and transmission stability even under significant deformation owing to the excellent liquidity and conductivity of liquid metal(LM).These properties are markedly better than those of solid metal connector.A compact induction electromagnet-driven method is optimized to significantly increase the LM flow rate and the active cooling capacity,resulting in sudden low temperature(<16℃at 1000 A).This synergetic cooling and charging strategy are expected to enable ultrahigh-heat-flux thermal management and accelerate development of the electric vehicle industry.展开更多
Flexible pressure sensors with high sensitivity are desired in the fields of electronic skins,human-machine interfaces,and health monitoring.Employing ionic soft materials with microstructured architectures in the fun...Flexible pressure sensors with high sensitivity are desired in the fields of electronic skins,human-machine interfaces,and health monitoring.Employing ionic soft materials with microstructured architectures in the functional layer is an effective way that can enhance the amplitude of capacitance signal due to generated electron double layer and thus improve the sensitivity of capacitive-type pressure sensors.However,the requirement of specific apparatus and the complex fabrication process to build such microstructures lead to high cost and low productivity.Here,we report a simple strategy that uses open-cell polyurethane foams with high porosity as a continuous three-dimensional network skeleton to load with ionic liquid in a one-step soak process,serving as the ionic layer in iontronic pressure sensors.The high porosity(95.4%) of PU-IL composite foam shows a pretty low Young's modulus of 3.4 kPa and good compressibility.A superhigh maximum sensitivity of 9,280 kPa^(-1) in the pressure regime and a high pressure resolution of 0.125% are observed in this foam-based pressure sensor.The device also exhibits remarkable mechanical stability over 5,000 compression-release or bending-release cycles.Such high porosity of composite structure provides a simple,cost-effective and scalable way to fabricate super sensitive pressure sensor,which has prominent capability in applications of water wave detection,underwater vibration sensing,and mechanical fault monitoring.展开更多
It is critical for the material to be of active supporting capacity before initial collapse ot mare root wltn supermgn water material backfill mining, and the maximum bending moment should be first calculated in order...It is critical for the material to be of active supporting capacity before initial collapse ot mare root wltn supermgn water material backfill mining, and the maximum bending moment should be first calculated in order to determine the initial collapse span. In the light of principal of virtual work, the simple expression of deflection, bending moment of elastic clamped plate were deduced under the condition of vertical uniform distributed load, horizontal pressure and supporting by elastic foundation, and then, the maximal bending moment expression was derived too. At the same time, the influence degree on square clamped plate by adding horizontal pressure and elastic foundation were analyzed. The results show that the effect of horizontal pressure on maximal bending moment can be ignored when the value of horizontal pressure is two orders of magni- tude less than that of coeificient of elastic stiffness existing elastic foundation.展开更多
Experimental and theoretical researches on the doping effect of interface binding state with homologous and heterogeneous dopants(d) in the system of PCD etc,as well as the action of intermediate layers between D /d a...Experimental and theoretical researches on the doping effect of interface binding state with homologous and heterogeneous dopants(d) in the system of PCD etc,as well as the action of intermediate layers between D /d at superhigh pressure and high temperature(HP-HT) are reported in this paper.展开更多
This paper explains the principle of a newly developed ZMLMC directional solidification apparatus with a superhigh temperature gradient.With the help of the apparatus,research was done on the change of directional sol...This paper explains the principle of a newly developed ZMLMC directional solidification apparatus with a superhigh temperature gradient.With the help of the apparatus,research was done on the change of directional solidification structures of the cobalt based superalloy K10 at superhigh velocities.Relations between the primary and secondary dendrite arm spacings and the cooling rates Were investigated.Experimental results show that the primary and secondary dendrite arm spacings of directionally solidified cobalt based superalloys are respectively finer than one fifth and one eighth of those produced by conventional directional soli-dification processes.The primary and secondary dendrite arm spacing which can be decreased by increasing the cooling rate,and the relations between these spacings(λ1,λ2)and the temperature gradient(G)and solidfication rate(v)were as follows:λ1=1.428×10^(3)(G·v)^-1_(1)λ_(2)=0.132×10^(3)(G·v)^-1.展开更多
Superhigh organosulfur coal has received considerable attention 'chemically as well as geologically,because from it we could get much useful chemical information for removing organosulfur from coal.By studying it,...Superhigh organosulfur coal has received considerable attention 'chemically as well as geologically,because from it we could get much useful chemical information for removing organosulfur from coal.By studying it, we could also find out the factors af-展开更多
THE Pingba soil profile developed on the bedrock Triassic dolomitite and morphologically located in uplandin karst terrain in Central Guizhou, China was proven to be in-situ dolomitite weathering pedogeneticproduct. C...THE Pingba soil profile developed on the bedrock Triassic dolomitite and morphologically located in uplandin karst terrain in Central Guizhou, China was proven to be in-situ dolomitite weathering pedogeneticproduct. Continuous sampling method was used for taking samples from man-made excavated pit fromthe Pingba profile. REE for samples was measured on ELEMENT ICP-MS in the Institute of Geochemistry, CAS. The standard reference samples GSR-6 and GSS-1,4,7 were used to monitor the precisionof REE measurement. The measurement error was less than ≤10%. For PB-T1 sample, the coefficientof variation (CV) of three analytical run precision is: La, Ce, Pr, Nd, Ho, Er≤10%; Sm, Eu, Dy,Tm≤15%; Y, Lu, Gd, Tb≤20%.展开更多
Characteristics of photosynthetic gas exchange, photoinhibition and C4 pathway enzyme activities in both flag leaves and lemma were compared between a superhigh-yield rice (Oryza sativa L.) hybrid, Liangyoupeijiu and ...Characteristics of photosynthetic gas exchange, photoinhibition and C4 pathway enzyme activities in both flag leaves and lemma were compared between a superhigh-yield rice (Oryza sativa L.) hybrid, Liangyoupeijiu and a traditional rice hybrid, Shanyou63. Liangyoupeijiu had a similar light saturated assimilation rate (Asat) to Shanyou63, but a much higher apparent quantum yield (AQY), carboxylation efficiency (CE) and quantum yield of CO2 fixation (φCO2). Liangyoupeijiu also showed a higher resistance to photoinhibition and higher non-radiative energy dissipation associated with the xanthophyll cycle than Shanyou63 when subjected to strong light. In addition, Liangyoupeijiu had higher activities of the C4 pathway enzymes in both flag leaves and lemmas than Shanyou63. These results indicate that higher light and CO2 use efficiency, higher resistance to photoinhibition and C4 pathway in both flag leaf and lemma may contribute to the higher yield of the superhigh-yield rice hybrid, Liangyoupeijiu.展开更多
基金supported by the National Key Research and Development Program of China(2022YFB2502000)the National Natural Science Foundation of China(52201277,52207244,52207245)+1 种基金the Xi'an Young Talent Lifting Program(959202413060)the National Outstanding Youth Foundation of China(52125104).
文摘Owing to anionic redox,cathode materials containing layered Li-rich Mn-based oxides(LLOs)are promising for the development of next-generation lithium-ion batteries(LIBs)with a large energy density(~500–600 Wh·kg^(−1)).However,these LLOs are easily degraded during cycling,which limits their lifespan.So far,the degradation mechanism is still under debate.Herein,LLOs are post-treated through implantation with energetic Ti ion flux(Ti-LLO),which modifies the structure of LLOs both at the surface and within the bulk.Unlike the dominant R3m phase(73.24%)observed in LLOs,the phase structure of Ti-LLO is altered,with Li-rich C2/m accounting for 67.72%in the bulk,alongside the formation of a thin(approximately 2 nm),uniform,and continuous Li-Ti-O spinel layer at the surface.Apart from phase structure changes,chemical valence states of transition metals and O,as well as their evolution,are analyzed and compared to charge transport kinetics to elucidate their contributions to the enhanced discharge capacity in Ti-LLOs.Besides,the role of the Li-Ti-O spinel layer at the surface in providing anticorrosion protection at the interface of LLOs/electrolyte during cycling is evaluated.As a result,we demonstrate that a superhigh discharge capacity(335.3 mAh·g^(−1))at 0.1 C can be achieved,along with prolonged cycling stability(showing capacity retention of approximately 80%after 500 cycles at 1 C)through these modifications.Moreover,we confirmed the universality of the strategy by implanting other ions,which offers practical strategies for achieving high performance in LLO cathode materials through thermodynamics and kinetics pathways.
基金the National Natural Science Foundation of China(NSFC)(52076213)the 2115 Talent Development Program of China Agricultural University for the financial coverage of this work。
文摘High-power direct current fast charging(DC-HPC),particularly for megawatt-level charging currents(≥1000 A),is expected to significantly reduce charging time and improve electric vehicle durability,despite the risk of instantaneous thermal shocks.Conventional cooling methods,which separately transmit current and heat,struggle to achieve both flexible maneuverability and high-efficiency cooling.In this study,we present a synergetic cooling and transmission strategy using a gallium-based liquid metal flexible charging connector(LMFCC),which efficiently dissipates ultra-high heat flux while simultaneously carrying superhigh current.The LMFCC exhibits exceptional flexible operability(bending radius of 2 cm)and transmission stability even under significant deformation owing to the excellent liquidity and conductivity of liquid metal(LM).These properties are markedly better than those of solid metal connector.A compact induction electromagnet-driven method is optimized to significantly increase the LM flow rate and the active cooling capacity,resulting in sudden low temperature(<16℃at 1000 A).This synergetic cooling and charging strategy are expected to enable ultrahigh-heat-flux thermal management and accelerate development of the electric vehicle industry.
基金This work was financially supported by the funds of the National Natural Science Foundation of China(No.51903118 and U1613204)the Science Technology the Shenzhen Sci-Tech Fund(No.KYTDPT20181011104007)+2 种基金M.G.also thanks the support of“College Student’s Innovation and Entrepreneurship Program”(No.2018X33).Guangdong Provincial Key Laboratory Program(2021B1212040001)from the Department of Science and Technology of Guangdong Provincethe“Guangdong Innovative and Entrepreneurial Research Team Program”under contract no.2016ZT06G587the“Science Technology and Innovation Committee of Shenzhen Municipality”(Grant No.JCYJ20170817111714314).
文摘Flexible pressure sensors with high sensitivity are desired in the fields of electronic skins,human-machine interfaces,and health monitoring.Employing ionic soft materials with microstructured architectures in the functional layer is an effective way that can enhance the amplitude of capacitance signal due to generated electron double layer and thus improve the sensitivity of capacitive-type pressure sensors.However,the requirement of specific apparatus and the complex fabrication process to build such microstructures lead to high cost and low productivity.Here,we report a simple strategy that uses open-cell polyurethane foams with high porosity as a continuous three-dimensional network skeleton to load with ionic liquid in a one-step soak process,serving as the ionic layer in iontronic pressure sensors.The high porosity(95.4%) of PU-IL composite foam shows a pretty low Young's modulus of 3.4 kPa and good compressibility.A superhigh maximum sensitivity of 9,280 kPa^(-1) in the pressure regime and a high pressure resolution of 0.125% are observed in this foam-based pressure sensor.The device also exhibits remarkable mechanical stability over 5,000 compression-release or bending-release cycles.Such high porosity of composite structure provides a simple,cost-effective and scalable way to fabricate super sensitive pressure sensor,which has prominent capability in applications of water wave detection,underwater vibration sensing,and mechanical fault monitoring.
基金Supported by the National Natural Science Foundation of China （41071273） the Special Research Fund for the Doctoral Program of Higher Education of China （200090095110002）
文摘It is critical for the material to be of active supporting capacity before initial collapse ot mare root wltn supermgn water material backfill mining, and the maximum bending moment should be first calculated in order to determine the initial collapse span. In the light of principal of virtual work, the simple expression of deflection, bending moment of elastic clamped plate were deduced under the condition of vertical uniform distributed load, horizontal pressure and supporting by elastic foundation, and then, the maximal bending moment expression was derived too. At the same time, the influence degree on square clamped plate by adding horizontal pressure and elastic foundation were analyzed. The results show that the effect of horizontal pressure on maximal bending moment can be ignored when the value of horizontal pressure is two orders of magni- tude less than that of coeificient of elastic stiffness existing elastic foundation.
文摘Experimental and theoretical researches on the doping effect of interface binding state with homologous and heterogeneous dopants(d) in the system of PCD etc,as well as the action of intermediate layers between D /d at superhigh pressure and high temperature(HP-HT) are reported in this paper.
基金supported by China National Natural Science foundation。
文摘This paper explains the principle of a newly developed ZMLMC directional solidification apparatus with a superhigh temperature gradient.With the help of the apparatus,research was done on the change of directional solidification structures of the cobalt based superalloy K10 at superhigh velocities.Relations between the primary and secondary dendrite arm spacings and the cooling rates Were investigated.Experimental results show that the primary and secondary dendrite arm spacings of directionally solidified cobalt based superalloys are respectively finer than one fifth and one eighth of those produced by conventional directional soli-dification processes.The primary and secondary dendrite arm spacing which can be decreased by increasing the cooling rate,and the relations between these spacings(λ1,λ2)and the temperature gradient(G)and solidfication rate(v)were as follows:λ1=1.428×10^(3)(G·v)^-1_(1)λ_(2)=0.132×10^(3)(G·v)^-1.
文摘Superhigh organosulfur coal has received considerable attention 'chemically as well as geologically,because from it we could get much useful chemical information for removing organosulfur from coal.By studying it, we could also find out the factors af-
文摘THE Pingba soil profile developed on the bedrock Triassic dolomitite and morphologically located in uplandin karst terrain in Central Guizhou, China was proven to be in-situ dolomitite weathering pedogeneticproduct. Continuous sampling method was used for taking samples from man-made excavated pit fromthe Pingba profile. REE for samples was measured on ELEMENT ICP-MS in the Institute of Geochemistry, CAS. The standard reference samples GSR-6 and GSS-1,4,7 were used to monitor the precisionof REE measurement. The measurement error was less than ≤10%. For PB-T1 sample, the coefficientof variation (CV) of three analytical run precision is: La, Ce, Pr, Nd, Ho, Er≤10%; Sm, Eu, Dy,Tm≤15%; Y, Lu, Gd, Tb≤20%.
基金This work was supported by the State Key Basic Research and Development Plan (G1998010100),the Program of 100 Distinguished Young Scientists of Chinese Academy of Sciences to Lu Congming, as well as the Innovative Foundation of Laboratory of Photosynt
文摘Characteristics of photosynthetic gas exchange, photoinhibition and C4 pathway enzyme activities in both flag leaves and lemma were compared between a superhigh-yield rice (Oryza sativa L.) hybrid, Liangyoupeijiu and a traditional rice hybrid, Shanyou63. Liangyoupeijiu had a similar light saturated assimilation rate (Asat) to Shanyou63, but a much higher apparent quantum yield (AQY), carboxylation efficiency (CE) and quantum yield of CO2 fixation (φCO2). Liangyoupeijiu also showed a higher resistance to photoinhibition and higher non-radiative energy dissipation associated with the xanthophyll cycle than Shanyou63 when subjected to strong light. In addition, Liangyoupeijiu had higher activities of the C4 pathway enzymes in both flag leaves and lemmas than Shanyou63. These results indicate that higher light and CO2 use efficiency, higher resistance to photoinhibition and C4 pathway in both flag leaf and lemma may contribute to the higher yield of the superhigh-yield rice hybrid, Liangyoupeijiu.
