Lithium-rich manganese-based oxides(LRMOs) exhibit high theoretical energy densities, making them a prominent class of cathode materials for lithium-ion batteries. However, the performance of these layered cathodes of...Lithium-rich manganese-based oxides(LRMOs) exhibit high theoretical energy densities, making them a prominent class of cathode materials for lithium-ion batteries. However, the performance of these layered cathodes often declines because of capacity fading during cycling. This decline is primarily attributed to anisotropic lattice strain and oxygen release from cathode surfaces. Given notable structural transformations, complex redox reactions, and detrimental interface side reactions in LRMOs, the development of a single modification approach that addresses bulk and surface issues is challenging. Therefore,this study introduces a surface double-coupling engineering strategy that mitigates bulk strain and reduces surface side reactions. The internal spinel-like phase coating layer, featuring threedimensional(3D) lithium-ion diffusion channels, effectively blocks oxygen release from the cathode surface and mitigates lattice strain. In addition, the external Li_(3)PO_(4) coating layer, noted for its superior corrosion resistance, enhances the interfacial lithium transport and inhibits the dissolution of surface transition metals. Notably, the spinel phase, as excellent interlayer, securely anchors Li_(3)PO_(4) to the bulk lattice and suppresses oxygen release from lattices. Consequently, these modifications considerably boost structural stability and durability, achieving an impressive capacity retention of 83.4% and a minimal voltage decay of 1.49 m V per cycle after 150 cycles at 1 C. These findings provide crucial mechanistic insights into the role of surface modifications and guide the development of high-capacity cathodes with enhanced cyclability.展开更多
The random nanofiber distribution in traditional electrospun membranes restricts the pressure sensing sensitivity and measurement range of electronic skin.Moreover,current multimodal sensing suffers from issues like o...The random nanofiber distribution in traditional electrospun membranes restricts the pressure sensing sensitivity and measurement range of electronic skin.Moreover,current multimodal sensing suffers from issues like overlapping signal outputs and slow response.Herein,a novel electrospinning method is proposed to prepare double-coupled microstructured nanofibrous membranes.Through the effect of high voltage electrostatic field in the electrospinning,the positively charged nanofibers are preferentially attached to the negatively charged foam surface,forming the ordered two-dimensional honey-comb porous nanofibrous membrane with three-dimensional spinous microstructure.Compared with the conventional random porous nanofibrous membrane,the bionic two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructures in the ordered porous nanofibrous membrane endows the electronic skin with significantly improved mechanical properties(maximum tensile strain increased by 77%and fatigue resistance increased by 35%),air permeability(water vapor transmission rate increased by 16%)and sensing properties(pressure sensitivity increased by 276%and detection range increased by 137%).Furthermore,the electronic skin was constructed by means of a conformal composite ionic liquid functionalized nanofibrous membrane,and the real-time and interference-free dualsignal monitoring of pressure and temperature(maxi-mum temperature coefficient of resistance:−0.918°C^(−1))was realized.展开更多
In this study,we propose a new method to determine full moment tensor solution for induced seismicity.This method generalizes the full waveform matching algorithm we have developed to determine the double-couple(DC)fo...In this study,we propose a new method to determine full moment tensor solution for induced seismicity.This method generalizes the full waveform matching algorithm we have developed to determine the double-couple(DC)focal mechanism based on the neighbourhood algorithm.One major difference between the new method and the former one is that we adopt a new misfit function to constrain the candidate moment tensor solutions with respect to a reference DC solution in addition to other misfit terms characterizing the waveform matching.Through synthetic tests using a real passive seismic survey geometry,the results show the new constraint can help better recover the DC components of inverted moment tensors.We further investigate how errors in the velocity model and source location affect the moment tensor solution.The synthetic test results indicate that the constrained inversion is robust in recovering both the DC and non-DC components.We also test the proposed method on several real induced events in an oil/gas field in Oman using the same observation system as synthetic tests.While it is found that the full moment tensor solutions without using the DC constraints have much larger non-DC components than solutions with the DC constraints,both solutions are able to fit the observed waveforms at similar levels.The synthetic and real test results suggest the proposed DC constrained inversion method can reliably retrieve full moment tensor solutions for the induced seismicity.展开更多
The double-coupled microwave resonance probe(DMRP)based on the hairpin probe is proposed for diagnosing atmospheric plasma jet(ne<1017 m-3).In this work,the resonance characteristics of DMRP are investigated by num...The double-coupled microwave resonance probe(DMRP)based on the hairpin probe is proposed for diagnosing atmospheric plasma jet(ne<1017 m-3).In this work,the resonance characteristics of DMRP are investigated by numerical simulation.It shows that two resonance peaks on the reflectance spectrum can be observed,and influenced significantly by some parameters,such as the probe separation,the distance to the handheld radio frequency atmospheric pressure glow discharge plasma jet(RF-APGDPJ)and the plasma electron density less than 1017 m-3.Based on two resonance modes of DMRP,the electron densities in the afterglow of RF-APGDPJ at the different rf powers and helium flow rates are diagnosed experimentally by matching the change of FWHM(Df1-Df1,airand Df2-Df2,air)measured by vector network analyzer with the simulated relation between the FWHM changes and the plasma density.展开更多
The focal mechanism solution is one of the important focal parameters for exploring fault activity and studying regional stress distribution and it has a wide range of applications. The geological structure of the Sic...The focal mechanism solution is one of the important focal parameters for exploring fault activity and studying regional stress distribution and it has a wide range of applications. The geological structure of the SichuanYunnan region in China is complex, with frequent earthquakes and abundant historical observation data, making it one of the popular areas of concern for scholars. This study utilizes the high-precision community velocity model v2.0 of southwest China, obtained through joint inversion based on multiple data methods. The Cut-AndPaste(CAP) method was employed to fit and invert the observed waveforms of 1475 events with M_(L)≥ 3.5 in the Sichuan-Yunnan region from January 2012 to December 2022, thereby constructing a catalog of double-couple focal mechanisms. By comparing the focal mechanism inversion results of small earthquakes with those from multiple one-dimensional velocity models and conducting comparative statistical analysis on events below magnitude 4, it has been demonstrated that the model used in this study provides a better fit than onedimensional models. This contributes to establishing the lower magnitude limit for producing deeper focal mechanism solutions. This study compares the results of larger magnitude earthquakes in the catalog with those published by the Global Centroid-Moment Tensor(GCMT) project and smaller magnitude earthquakes with the catalog released by the Institute of Earthquake Forecasting, China Earthquake Administration. These comparisons serve to validate the accuracy of the catalog results. Leveraging the high-resolution velocity model, this catalog has re-examined the historical earthquake focal mechanism catalog of the Sichuan-Yunnan region. The inversion has yielded reliable results for smaller magnitudes and a greater number of events, providing additional data and support for understanding the regional stress field, active faults, the mechanisms of large earthquake genesis, and earthquake prediction efforts. Consequently, this enhances the depth of scientific research in the Sichuan-Yunnan region.展开更多
基金National Natural Science Foundation of China (22179008, 21875022)Yibin ‘Jie Bang Gua Shuai’ (2022JB004)+3 种基金support from the Beijing Nova Program (20230484241)support from the Postdoctoral Fellowship Program of CPSF (GZB20230931)Special Support of the Chongqing Postdoctoral Research Project (2023CQBSHTB2041)Initial Energy Science & Technology Co., Ltd (IEST)。
文摘Lithium-rich manganese-based oxides(LRMOs) exhibit high theoretical energy densities, making them a prominent class of cathode materials for lithium-ion batteries. However, the performance of these layered cathodes often declines because of capacity fading during cycling. This decline is primarily attributed to anisotropic lattice strain and oxygen release from cathode surfaces. Given notable structural transformations, complex redox reactions, and detrimental interface side reactions in LRMOs, the development of a single modification approach that addresses bulk and surface issues is challenging. Therefore,this study introduces a surface double-coupling engineering strategy that mitigates bulk strain and reduces surface side reactions. The internal spinel-like phase coating layer, featuring threedimensional(3D) lithium-ion diffusion channels, effectively blocks oxygen release from the cathode surface and mitigates lattice strain. In addition, the external Li_(3)PO_(4) coating layer, noted for its superior corrosion resistance, enhances the interfacial lithium transport and inhibits the dissolution of surface transition metals. Notably, the spinel phase, as excellent interlayer, securely anchors Li_(3)PO_(4) to the bulk lattice and suppresses oxygen release from lattices. Consequently, these modifications considerably boost structural stability and durability, achieving an impressive capacity retention of 83.4% and a minimal voltage decay of 1.49 m V per cycle after 150 cycles at 1 C. These findings provide crucial mechanistic insights into the role of surface modifications and guide the development of high-capacity cathodes with enhanced cyclability.
基金supported by the National Natural Science Foundation of China(No.52275191)the Major Program of the National Natural Science Foundation of China for Basic Theory and Key Technology of Tri-Co Robots(No.92248301)the 333 Project of Jiangsu Province and Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_3622).
文摘The random nanofiber distribution in traditional electrospun membranes restricts the pressure sensing sensitivity and measurement range of electronic skin.Moreover,current multimodal sensing suffers from issues like overlapping signal outputs and slow response.Herein,a novel electrospinning method is proposed to prepare double-coupled microstructured nanofibrous membranes.Through the effect of high voltage electrostatic field in the electrospinning,the positively charged nanofibers are preferentially attached to the negatively charged foam surface,forming the ordered two-dimensional honey-comb porous nanofibrous membrane with three-dimensional spinous microstructure.Compared with the conventional random porous nanofibrous membrane,the bionic two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructures in the ordered porous nanofibrous membrane endows the electronic skin with significantly improved mechanical properties(maximum tensile strain increased by 77%and fatigue resistance increased by 35%),air permeability(water vapor transmission rate increased by 16%)and sensing properties(pressure sensitivity increased by 276%and detection range increased by 137%).Furthermore,the electronic skin was constructed by means of a conformal composite ionic liquid functionalized nanofibrous membrane,and the real-time and interference-free dualsignal monitoring of pressure and temperature(maxi-mum temperature coefficient of resistance:−0.918°C^(−1))was realized.
基金We want to thank the reviewers for their valuable comments about this manuscript.This study is funded by the National Science and Technology Major Project of China(No.2016ZX05023004)the National Natural Science Foundation of China(Nos.41804040 and 41861134009).
文摘In this study,we propose a new method to determine full moment tensor solution for induced seismicity.This method generalizes the full waveform matching algorithm we have developed to determine the double-couple(DC)focal mechanism based on the neighbourhood algorithm.One major difference between the new method and the former one is that we adopt a new misfit function to constrain the candidate moment tensor solutions with respect to a reference DC solution in addition to other misfit terms characterizing the waveform matching.Through synthetic tests using a real passive seismic survey geometry,the results show the new constraint can help better recover the DC components of inverted moment tensors.We further investigate how errors in the velocity model and source location affect the moment tensor solution.The synthetic test results indicate that the constrained inversion is robust in recovering both the DC and non-DC components.We also test the proposed method on several real induced events in an oil/gas field in Oman using the same observation system as synthetic tests.While it is found that the full moment tensor solutions without using the DC constraints have much larger non-DC components than solutions with the DC constraints,both solutions are able to fit the observed waveforms at similar levels.The synthetic and real test results suggest the proposed DC constrained inversion method can reliably retrieve full moment tensor solutions for the induced seismicity.
基金supported by National Natural Science Foundation of China(No.11075033)。
文摘The double-coupled microwave resonance probe(DMRP)based on the hairpin probe is proposed for diagnosing atmospheric plasma jet(ne<1017 m-3).In this work,the resonance characteristics of DMRP are investigated by numerical simulation.It shows that two resonance peaks on the reflectance spectrum can be observed,and influenced significantly by some parameters,such as the probe separation,the distance to the handheld radio frequency atmospheric pressure glow discharge plasma jet(RF-APGDPJ)and the plasma electron density less than 1017 m-3.Based on two resonance modes of DMRP,the electron densities in the afterglow of RF-APGDPJ at the different rf powers and helium flow rates are diagnosed experimentally by matching the change of FWHM(Df1-Df1,airand Df2-Df2,air)measured by vector network analyzer with the simulated relation between the FWHM changes and the plasma density.
基金the National Key Research and Development Program for supporting this study (Project No.: 2021YFC3000701-03, 2021YFC3000705)。
文摘The focal mechanism solution is one of the important focal parameters for exploring fault activity and studying regional stress distribution and it has a wide range of applications. The geological structure of the SichuanYunnan region in China is complex, with frequent earthquakes and abundant historical observation data, making it one of the popular areas of concern for scholars. This study utilizes the high-precision community velocity model v2.0 of southwest China, obtained through joint inversion based on multiple data methods. The Cut-AndPaste(CAP) method was employed to fit and invert the observed waveforms of 1475 events with M_(L)≥ 3.5 in the Sichuan-Yunnan region from January 2012 to December 2022, thereby constructing a catalog of double-couple focal mechanisms. By comparing the focal mechanism inversion results of small earthquakes with those from multiple one-dimensional velocity models and conducting comparative statistical analysis on events below magnitude 4, it has been demonstrated that the model used in this study provides a better fit than onedimensional models. This contributes to establishing the lower magnitude limit for producing deeper focal mechanism solutions. This study compares the results of larger magnitude earthquakes in the catalog with those published by the Global Centroid-Moment Tensor(GCMT) project and smaller magnitude earthquakes with the catalog released by the Institute of Earthquake Forecasting, China Earthquake Administration. These comparisons serve to validate the accuracy of the catalog results. Leveraging the high-resolution velocity model, this catalog has re-examined the historical earthquake focal mechanism catalog of the Sichuan-Yunnan region. The inversion has yielded reliable results for smaller magnitudes and a greater number of events, providing additional data and support for understanding the regional stress field, active faults, the mechanisms of large earthquake genesis, and earthquake prediction efforts. Consequently, this enhances the depth of scientific research in the Sichuan-Yunnan region.
