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Limited Sea Surface Temperature Cooling Due to the Barrier Layer Promoting Super Typhoon Mangkhut(2018)
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作者 Huipeng WANG Jiagen LI +8 位作者 Junqiang SONG Liang SUN Fu LIU Han ZHANG Kaijun REN Huizan WANG Chunming WANG Jinrong ZHANG Hongze LENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2156-2172,共17页
This study investigates the impact of the salinity barrier layer(BL)on the upper ocean response to Super Typhoon Mangkhut(2018)in the western North Pacific.After the passage of Mangkhut,a noticeable increase(~0.6 psu)... This study investigates the impact of the salinity barrier layer(BL)on the upper ocean response to Super Typhoon Mangkhut(2018)in the western North Pacific.After the passage of Mangkhut,a noticeable increase(~0.6 psu)in sea surface salinity and a weak decrease(<1℃)in sea surface temperature(SST)were observed on the right side of the typhoon track.Mangkhut-induced SST change can be divided into the three stages,corresponding to the variations in BL thickness and SST before,during,and after the passage of Mangkhut.During the pre-typhoon stage,SST slightly warmed due to the entrainment of BL warm water,which suppressed the cooling induced by surface heat fluxes and horizontal advection.During the forced stage,SST cooling was controlled by entrainment,and the preexisting BL reduced the total cooling by 0.89℃ d-1,thus significantly weakening the overall SST cooling induced by Mangkhut.During the relaxation stage,the SST cooling was primarily caused by the entrainment.Our results indicate that a preexisting BL can limit typhoon-induced SST cooling by suppressing the entrainment of cold thermocline water,which contributed to Mangkhut becoming the strongest typhoon in 2018. 展开更多
关键词 sea surface cooling mixed-layer depth barrier layer TYPHOON
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Surface encapsulation of layered oxide cathode material with NiTiO_(3) for enhanced cycling stability of Na-ion batteries
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作者 胡紫霖 唐彬 +8 位作者 林挺 张楚 牛耀申 刘渊 高立克 谢飞 容晓晖 陆雅翔 胡勇胜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期551-558,共8页
In Na-ion batteries,O3-type layered oxide cathode materials encounter challenges such as particle cracking,oxygen loss,electrolyte side reactions,and multi-phase transitions during the charge/discharge process.This st... In Na-ion batteries,O3-type layered oxide cathode materials encounter challenges such as particle cracking,oxygen loss,electrolyte side reactions,and multi-phase transitions during the charge/discharge process.This study focuses on surface coating with NiTiO_(3) achieved via secondary heat treatment using a coating precursor and the surface material.Through in-situ x-ray diffraction(XRD)and differential electrochemical mass spectrometry(DEMS),along with crystal structure characterizations of post-cycling materials,it was determined that the NiTiO_(3) coating layer facilitates the formation of a stable lattice structure,effectively inhibiting lattice oxygen loss and reducing side reaction with the electrolyte.This enhancement in cycling stability was evidenced by a capacity retention of approximately 74%over 300 cycles at 1 C,marking a significant 30%improvement over the initial sample.Furthermore,notable advancements in rate performance were observed.Experimental results indicate that a stable and robust surface structure substantially enhances the overall stability of the bulk phase,presenting a novel approach for designing layered oxide cathodes with higher energy density. 展开更多
关键词 Na-ion battery layered oxides high voltage surface coating
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Boosting rate performance of layered lithium-rich cathode materials by oxygen vacancy induced surface multicomponent integration
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作者 Youyou Fang Yuefeng Su +7 位作者 Jinyang Dong Jiayu Zhao Haoyu Wang Yun Lu Bin Zhang Hua Yan Feng Wu Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期250-262,共13页
The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(... The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(LLO)materials inherently excel.However,these materials face practical challenges,such as low initial Coulombic efficiency,inferior cycle/rate performance,and voltage decline during cycling,which limit practical application.Our study introduces a surface multi-component integration strategy that incorporates oxygen vacancies into the pristine LLO material Li1.2Mn_(0.6)Ni_(0.2)O_(2).This process involves a brief citric acid treatment followed by calcination,aiming to explore rate-dependent degradation behavior.The induced surface oxygen vacancies can reduce surface oxygen partial pressure and diminish the generation of O_(2)and other highly reactive oxygen species on the surface,thereby facilitating the activation of Li ions trapped in tetrahedral sites while overcoming transport barriers.Additionally,the formation of a spinel-like phase with 3D Li+diffusion channels significantly improves Li^(+)diffusion kinetics and stabilizes the surface structure.The optimally modified sample boasts a discharge capacity of 299.5 mA h g^(-1)at a 0.1 C and 251.6 mA h g^(-1)at a 1 C during the initial activation cycle,with an impressive capacity of 222.1 mA h g^(-1)at a 5 C.Most notably,it retained nearly 70%of its capacity after 300 cycles at this elevated rate.This straightforward,effective,and highly viable modification strategy provides a crucial resolution for overcoming challenges associated with LLO materials,making them more suitable for practical application. 展开更多
关键词 Lithium-ion battery layered lithium rich cathode surface multicomponent integration Rate-dependent degradation and Li^(+) diffusion kinetics
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Intelligent Reflecting Surface-Aided Secure and Covert Communications
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作者 Zhou Xiaobo Jiang Yong +2 位作者 Xia Tingting Xia Guiyang Shen Tong 《China Communications》 SCIE CSCD 2024年第9期1-10,共10页
This work employs intelligent reflecting surface(IRS)to enhance secure and covert communication performance.We formulate an optimization problem to jointly design both the reflection beamformer at IRS and transmit pow... This work employs intelligent reflecting surface(IRS)to enhance secure and covert communication performance.We formulate an optimization problem to jointly design both the reflection beamformer at IRS and transmit power at transmitter Alice in order to optimize the achievable secrecy rate at Bob subject to a covertness constraint.We first develop a Dinkelbach-based algorithm to achieve an upper bound performance and a high-quality solution.For reducing the overhead and computational complexity of the Dinkelbach-based scheme,we further conceive a low-complexity algorithm in which analytical expression for the IRS reflection beamforming is derived at each iteration.Examination result shows that the devised low-complexity algorithm is able to achieve similar secrecy rate performance as the Dinkelbach-based algorithm.Our examination also shows that introducing an IRS into the considered system can significantly improve the secure and covert communication performance relative to the scheme without IRS. 展开更多
关键词 covert communications intelligent reflecting surface physical layer security reflection beamforming
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Enhanced structural stability and durability in lithium-rich manganese-based oxide via surface double-coupling engineering
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作者 Jiayu Zhao Yuefeng Su +10 位作者 Jinyang Dong Xi Wang Yun Lu Ning Li Qing Huang Jianan Hao Yujia Wu Bin Zhang Qiongqiong Qi Feng Wu Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期274-283,共10页
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
关键词 Lithium-ion battery layered lithium-rich cathode surface double-coupling engineering Lattice strain Oxygen release
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Surface engineering of P2-type cathode material targeting long-cycling and high-rate sodium-ion batteries
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作者 Jun Xiao Yang Xiao +11 位作者 Shijian Wang Zefu Huang Jiayi Li Cheng Gong Guilai Zhang Bing Sun Hong Gao Huiqiao Li Xin Guo Yong Wang Hao Liu Guoxiu Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期444-452,I0009,共10页
The widespread interest in layered P2-type Mn-based cathode materials for sodium-ion batteries(SIBs)stems from their cost-effectiveness and abundant resources.However,the inferior cycle stability and mediocre rate per... The widespread interest in layered P2-type Mn-based cathode materials for sodium-ion batteries(SIBs)stems from their cost-effectiveness and abundant resources.However,the inferior cycle stability and mediocre rate performance impede their further development in practical applications.Herein,we devised a wet chemical precipitation method to deposit an amorphous aluminum phosphate(AlPO_(4),denoted as AP)protective layer onto the surface of P2-type Na_(0.55)Ni_(0.1)Co_(0.7)Mn_(0.8)O_(2)(NCM@AP).The resulting NCM@5AP electrode,with a 5 wt%coating,exhibits extended cycle life(capacity retention of78.4%after 200 cycles at 100 mA g^(-1))and superior rate performance(98 mA h g^(-1)at 500 mA g^(-1))compared to pristine NCM.Moreover,our investigation provides comprehensive insights into the phase stability and active Na^(+)ion kinetics in the NCM@5AP composite electrode,shedding light on the underlying mechanisms responsible for the enhanced performance observed in the coated electrode. 展开更多
关键词 layered metal oxides Sodium-ion batteries P2-type structure surface engineering
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A Facile Li_(2)TiO_(3) Surface Modification to Improve the Structure Stability and Electrochemical Performance of Full Concentration Gradient Li-Rich Oxides
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作者 Naifang Hu Yuan Yang +5 位作者 Lin Li Yuhan Zhang Zhiwei Hu Lan Zhang Jun Ma Guanglei Cui 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期41-48,共8页
Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rat... Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rate performance,whereas the high lithium residues on its surface impairs the structure stability and long-term cycle performance.Herein,a facile multifunctional surface modification method is implemented to eliminate surface lithium residues of full concentration gradient lithium-rich layered oxides by a wet chemistry reaction with tetrabutyl titanate and the post-annealing process.It realizes not only a stable Li_(2)TiO_(3)coating layer with 3D diffusion channels for fast Li^(+)ions transfer,but also dopes partial Ti^(4+)ions into the sub-surface region of full concentration gradient lithium-rich layered oxides to further strengthen its crystal structure.Consequently,the modified full concentration gradient lithium-rich layered oxides exhibit improved structure stability,elevated thermal stability with decomposition temperature from 289.57℃to 321.72℃,and enhanced cycle performance(205.1 mAh g^(-1)after 150 cycles)with slowed voltage drop(1.67 mV per cycle).This work proposes a facile and integrated modification method to enhance the comprehensive performance of full concentration gradient lithium-rich layered oxides,which can facilitate its practical application for developing higher energy density lithium-ion batteries. 展开更多
关键词 full concentration gradient lithium-rich layered oxides structure stability surface modification
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Effect of porous surface layer on wave propagation in elastic cylinder immersed in fluid
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作者 苏娜娜 韩庆邦 +1 位作者 单鸣雷 殷澄 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期340-353,共14页
To study the damage to an elastic cylinder immersed in fluid, a model of an elastic cylinder wrapped with a porous medium immersed in fluid is designed. This structure can both identify the properties of guided waves ... To study the damage to an elastic cylinder immersed in fluid, a model of an elastic cylinder wrapped with a porous medium immersed in fluid is designed. This structure can both identify the properties of guided waves in a more practical model and address the relationship between the cylinder damage degree and the surface and surrounding medium. The principal motivation is to perform a detailed quantitative analysis of the longitudinal mode and flexural mode in an elastic cylinder wrapped with a porous medium immersed in fluid. The frequency equations for the propagation of waves are derived each for a pervious surface and an impervious surface by employing Biot theory. The influences of the various parameters of the porous medium wrapping layer on the phase velocity and attenuation are discussed. The results show that the influences of porosity on the dispersion curves of guided waves are much more significant than those of thickness,whereas the phase velocity is independent of the static permeability. There is an apparent “mode switching” between the two low-order modes. The characteristics of attenuation are in good agreement with the results from the dispersion curves.This work can support future studies for optimizing the theory on detecting the damage to cylinder or pipeline. 展开更多
关键词 wave propagation porous surface layer DISPERSION ATTENUATION
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Sub-nano Layers of Li, Be, and Al on the Si(100) Surface: Electronic Structure and Silicide Formation
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作者 Victor Zavodinsky Oga Gorkusha 《Semiconductor Science and Information Devices》 2023年第1期11-17,共7页
Within the framework of the density functional theory and the pseudopotential method,the electronic structure calculations of the“metal-Si(100)”systems with Li,Be and Al as metal coverings of one to four monolayers(... Within the framework of the density functional theory and the pseudopotential method,the electronic structure calculations of the“metal-Si(100)”systems with Li,Be and Al as metal coverings of one to four monolayers(ML)thickness,were carried out.Calculations showed that band gaps of 1.02 eV,0.98 eV and 0.5 eV,respectively,appear in the densities of electronic states when the thickness of Li,Be and Al coverings is one ML.These gaps disappear with increasing thickness of the metal layers:first in the Li-Si system(for two ML),then in the Al-Si system(for three ML)and then in the Be-Si system(for four ML).This behavior of the band gap can be explained by the passivation of the substrate surface states and the peculiarities of the electronic structure of the adsorbed metals.In common the results can be interpreted as describing the possibility of the formation of a two-dimensional silicide with semiconducting properties in Li-Si(100),Be-Si(100)and Al-Si(100)systems. 展开更多
关键词 Kohn-Sham method PSEUDOPOTENTIALS Si(100)surface Sub-nano metal layers Density of states Two-dimensional silicides Semiconducting properties
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Tribological behaviors of Fe-Al-Cr-Nb alloyed layer deposited on 45 steel via double glow plasma surface metallurgy technique 被引量:2
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作者 罗西希 姚正军 +6 位作者 张平则 陈煜 杨红勤 吴小凤 张泽磊 林玉划 徐尚君 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3694-3699,共6页
Double glow plasma surface metallurgy technique was used to fabricate a Fe?Al?Cr?Nb alloyed layer onto the surface of the 45 steel. The microstructures and composition of th?eA Fl?eCr?Nb alloyed layer were analyzed by... Double glow plasma surface metallurgy technique was used to fabricate a Fe?Al?Cr?Nb alloyed layer onto the surface of the 45 steel. The microstructures and composition of th?eA Fl?eCr?Nb alloyed layer were analyzed by scanning electronic microscopy, X-ray diffraction and energy dispersive spectroscopy. The results indicate thatthe 20 μm alloyed layer is homogeneous and compact. The alloyed elements exhibit a gradient distribution along the cross section. Microhardness and nanoindentation tests imply that the surface hardness of the alloyed layer reaches HV 580, which is almost 2.8 times that of the substrate. Compared with the substrate, the alloyed layer has a much smaller displacement and a larger elastic modulus. According to the friction and wear tests at room temperature, the? FeAl?Cr?Nb alloyed layer has lower friction coefficient and less wear mass, implying that the Fe?Al?Cr?Nb alloyed layer can effectively improve the surface hardness and wear resistance of the substrate. 展开更多
关键词 Fe-Al-Cr-Nb alloyed layer double glow plasma surface metallurgy technique tribological behavior
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Concentrations,Accumulation and Sources of PAHs in Surface Layer Sediments of Taizhou Bay
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作者 金彬明 江锦花 《Marine Science Bulletin》 CAS 2008年第1期38-45,共8页
The concentrations, accumulation and sources of 15 polycyclic aromatic hydrocarbons (PAHs) had been studied or evaluated in the surface layer sediments of Taizhou Bay, China. It showed that the concentrations of PAH... The concentrations, accumulation and sources of 15 polycyclic aromatic hydrocarbons (PAHs) had been studied or evaluated in the surface layer sediments of Taizhou Bay, China. It showed that the concentrations of PAHs ranged from 85.4 to 167.6 ng/g (averaged 138.62 ng/g), and the highest level was found in Jiao Jiang Dock. Percentages of 2-, 3-, 4-, 5- and 6-cyclic aromatic hydrocarbons were 7.8 %, 42.1%, 33.3 %, 9.6 % and 7.2 % respectively. The accumulation indices of PAHs ranged from 532.7 to 1068.9 (averaged 807.5), and the index of Phenanthrene was the highest (122.7), while that of Benzo (a) Pyrene was the lowest (2.7) among them. In Taizhou Bay, PAHs in surface layer sediments came mainly from coal burning, partly from direct pollution of petroleum hydrocarbons. 展开更多
关键词 Taizhou Bay surface layer sediment PAHS Concentration
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Effects of Straw Covering and Different Types of Potassium Fertilizer on Salinity Accumulation in Surface Layer of Tobacco-planted Paddy Soil 被引量:3
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作者 彭金良 雷文杰 +1 位作者 黄景崇 李迪秦 《Agricultural Science & Technology》 CAS 2013年第6期905-910,共6页
[Objective] This study aimed to investigation the effects of straw covering and different types of potassium fertilizer on salinity accumulation in surface layer of tobacco-planted paddy soil in southern China. [Metho... [Objective] This study aimed to investigation the effects of straw covering and different types of potassium fertilizer on salinity accumulation in surface layer of tobacco-planted paddy soil in southern China. [Method] Tobacco variety ‘Yunyan87’ was used as the experimental material to investigate the effects of salinity accumulation in surface layer of tobacco-planted paddy soil on the growth and development of flue-cured tobacco using different types of potassium fertilizer and mulching cultivation methods. [Result] The results showed that K+ , Ca2+ , SO42and NO3-were the major salt ions in topsoil at different growth stages of flue-cured tobacco, Na + and Mg2+ contents were also relatively high at vigorous growth stage, indicating that these salt ions were easily accumulated in surface layer of soil; to be specific, the absolute increase of salt ion concentration showed a decreasing order of K+ SO42- NO3-Ca2+ Mg2+ Na+ Cl-, while the relative increase of salt ion concentration showed a decreasing order of Ca2+ K+ Na+ NO3-SO42-Mg2+ Cl-. At 60 d posttransplanting, total salt content in topsoil reached the minimum of 359.1 mg/kg in Treatment 2, total salt content in topsoil reached the maximum of 536.1 mg/kg in Treatment 5 (CK), which was significantly higher than that in other treatments. At 90 d post-transplanting, no significant difference was observed in total salt content among various treatments. At harvesting period, total salt content in topsoil reached the maximum of 3 278.4 mg/kg in Treatment 1, which was significantly higher than that in other treatments. Topsoil pH showed no significant differences among various treatments at three different periods, ranging from 5.39 to 5.59. Straw covering could effectively reduce salt content in topsoil, accelerate vigorous growth of tobacco, shorten vigorous growth period and increase plant height, leaf number and lead area; at vigorous growth stage, root vitality and root volume of tobacco were improved, but the yield and output value were relatively low. Major agronomic traits and yield of tobacco showed no significant difference among various treatments. Output value of tobacco reached the maximum of 24 196.8 yuan/hm2 in Treatment 3, which was significantly higher than that in other treatments. [Conclusion] Appropriate types and proportions of potassium fertilizer and straw covering can effectively reduce the total salt content in tobacco-planted paddy soil and increase the effective supply amount of K+ , Ca2+ , SO42-and NO3-, thereby promoting and improving the root vitality of tobacco, which is conducive to the growth and development of tobacco and will eventually enhance the yield, quality and economic benefits of flue-cured tobacco. 展开更多
关键词 Flue-cured tobacco Tobacco-planted paddy soil Salinity accumulation in surface layer Potassium fertilizer Straw covering
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Stable cycling of LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/lithium metal batteries enabled by synergistic tuning the surface stability of cathode/anode 被引量:1
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作者 Chunli Li Xinyu Zhang +8 位作者 Zhuolin Yang Haijian Lv Tinglu Song Shijie Lu Yuxiang Zhang Tianwen Yang Fan Xu Feng Wu Daobin Mu 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期342-350,I0009,共10页
Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion batteries.However,due to the high surface sensitivity,their practical application is hindered by inte... Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion batteries.However,due to the high surface sensitivity,their practical application is hindered by interfacial instability with electrolytes under high voltage for long cyclic life.Herein,by combining both firstprinciple calculations and time-of-flight secondary ion mass spectrometry(TOF-SIMS),a novel surface fluorinated reconstruction(SFR)mechanism is proposed to improve the interfacial stability under high voltage,which could effectively regulate the surface fluoride species to desensitize the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)interface.We demonstrate here that by tuning the ratio of fluoride species,the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/Li battery could achieve excellent long-term and high voltage performance(163.5 mA h g^(-1)at 0.5 C for 300 cycles under 4.4 V),while the controlled sample decayed to 125.4 mA h g^(-1)after 300 cycles.Moreover,the favorable cross-talk effect induced by SFR further facilitates the incorporation of suitable amounts of Ni ions into the construction of stable solid electrolyte interface(SEI)layer for anode surface.Therefore,the ultra-long cycling stability under high voltage can be achieved by the robust cathode/electrolyte and Li/electrolyte interfaces,which results in excellent interfacial stability after long cycling.This work provides new insights into the surface design of cathode materials and improves the stability of the electrode-electrode interface under high voltage. 展开更多
关键词 Ni-rich layered oxides surface fluorinated reconstruction Interfacial stability TOF-SIMS Cross-talk effect
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Anti-Corrosion and Reconstruction of Surface Crystal Plane for Zn Anodes by an Advanced Metal Passivation Technique 被引量:1
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作者 Si Liu Hongxin Lin +2 位作者 Qianqian Song Jian Zhu Changbao Zhu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期166-172,共7页
For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatme... For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatment to solve these issues for Zn anodes are still great challenges.Herein,a simple and cheap metal passivation technique is proposed for Zn anodes from a corrosion science perspective.Similar to the metal anticorrosion engineering,the formed interfacial protective layer in a chemical way can sufficiently solve the corrosion issues.Furthermore,the proposed passivity approach can reconstruct Zn surface-preferred crystal planes,exposing more(002)planes and improving surface hydrophilicity,which inhibits the formation of Zn dendrites and hydrogen evolution effectively.As expected,the passivated Zn achieves outstanding cycling life(1914 h)with low voltage polarization(<40 mV).Even at 6 mA cm^(−2) and 3 mA h cm^(−2),it can achieve stable Zn deposition over 460 h.The treated Zn anode coupled with MnO_(2) cathode shows prominently reinforced full batteries service life,making it a potential Zn anode candidate for excellent performance aqueous Zn-ion batteries.The proposed passivation approach provides a guideline for other metal electrodes preparation in various batteries and establishes the connections between corrosion science and batteries. 展开更多
关键词 ANTI-CORROSION aqueous zinc ion battery interfacial protective layer metal passivation technique reconstruction of surface crystal plane
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Using a Modified Soil-Plant-Atmosphere Scheme(MSPAS)to Simulate the Interaction between Land Surface Processes and Atmospheric Boundary Layer in Semi-Arid Regions 被引量:20
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作者 树华 乐旭 +1 位作者 胡非 刘辉志 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第2期245-259,共15页
This paper uses a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to study the interaction between land surface and atmospheric boundary layer processes. The scheme is composed of two main parts: atmospheric boundary la... This paper uses a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to study the interaction between land surface and atmospheric boundary layer processes. The scheme is composed of two main parts: atmospheric boundary layer processes and land surface processes. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feasibility of the model is well proved in this paper. The numerical simulation results from MSPAS show good agreement with reality. The scheme is used to obtain reasonable simulations for diurnal variations of heat balance, potential temperature of boundary layer, and wind field, and spatial distributions of temperature, specific humidity, vertical velocity, turbulence kinetic energy, and turbulence exchange coefficient over desert and oasis. In addition, MSPAS is used to simulate the interaction between desert and oasis at night, and again it obtains reasonable results. This indicates that MSPAS can be used to study the interaction between land surface processes and the atmospheric boundary layer over various underlying surfaces and can be extended for regional climate and numerical weather prediction study. 展开更多
关键词 modified soil-plant-atmosphere scheme (MSPAS) land surface processes (LSP) atmospheric boundary layer
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An Application of the RAMS/FLUENT System on the Multi-Scale Numerical Simulation of the Urban Surface Layer—A Preliminary Study 被引量:11
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作者 李磊 胡非 +1 位作者 姜金华 程雪玲 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第2期271-280,共10页
The Regional Atmospheric Modeling System (RAMS) and the computational fluid dynamics (CFD) codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer (USL)... The Regional Atmospheric Modeling System (RAMS) and the computational fluid dynamics (CFD) codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer (USL). RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL. 展开更多
关键词 multi-scale numerical simulation urban surface layer (USL) urban canopy layer (UCL) RAMS/FLUENT system
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Numerical simulation of surface movement laws under different unconsolidated layers thickness 被引量:5
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作者 DAI Hua-yang1, LI Wen-chang2, LIU Yi-xin1,3, JIANG Yao-dong3 1. College of Geosicence and Surveying Engineering, China University of Mining and Technology, Beijing 100083, China 2. College of Resources and Safety Engineering, China University of Mining and Technology, Beijing 100083, China 3. College of Mechanics and Civil Engineering, China University of Mining and Technology, Beijing 100083, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期599-603,共5页
Based on specific geology and mining conditions of certain coal working face in China, a series of numerical models under different unconsolidated layers thickness were respectively established by employing FLAC3D. Th... Based on specific geology and mining conditions of certain coal working face in China, a series of numerical models under different unconsolidated layers thickness were respectively established by employing FLAC3D. The relationship between the unconsolidated layers thickness and surface movement laws was studied. Maximum surface subsidence, Maximum horizontal displacement and surface subsidence degree were obtained. Contours of surface subsidence/horizontal displacement and curves were drawn. Some laws of surface subsidence/horizontal displacement were analyzed. The role of the unconsolidated layers in surface subsidence was revealed. It is significant to predict surface subsidence of thick unconsolidated layers for coal mine and take effective measures to control surface subsidence. 展开更多
关键词 unconsolidated layerS surface MOVEMENT NUMERICAL simulation deep MINING FLAC3D
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PROPAGATION OF SURFACE ACOUSTIC WAVES IN PRESTRESSED ANISOTROPIC LAYERED PIEZOELECTRIC STRUCTURES 被引量:5
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作者 Liu Hua Kuang Zhenbang +2 位作者 Cai Zhengming Wang Tiejun Wang Zikun 《Acta Mechanica Solida Sinica》 SCIE EI 2003年第1期16-23,共8页
The propagation of surface acoustic waves in layered piezoelectric structureswith initial stresses is investigated. The phase velocity equations are obtained for electricallyfree and shorted cases, respectively. Effec... The propagation of surface acoustic waves in layered piezoelectric structureswith initial stresses is investigated. The phase velocity equations are obtained for electricallyfree and shorted cases, respectively. Effects of the initial stresses on the phase velocity and theelectromechanical coupling coefficient for the fundamental mode of the layered piezoelectricstructures are discussed. Numerical results for the c-axis oriented film of LiNbO_3 on a sapphiresubstrate are given. It is found that the fractional change in phase velocity is a linear functionwith the initial stresses, and the electromechanical coupling factor increases with an increase ofthe absolute values of the compressive initial stresses. The results are useful for the design ofsurface acoustic wave devices. 展开更多
关键词 surface acoustic waves layered piezoelectric structure phase velocity electromechanical coupling coefficient
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THE NAVIER-STOKES EQUATIONS IN STREAM LAYER AND ON STREAM SURFACE AND A DIMENSION SPLIT METHODS 被引量:5
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作者 Li Kaitai(李开泰) +1 位作者 Huang Aixiang(黄艾香) 《Academic Journal of Xi'an Jiaotong University》 2002年第2期89-100,120,共13页
In this paper,we proposal stream surface and stream layer.By using classical tensor calculus,we derive 3-D Navier-Stokes Equations(NSE)in the stream layer under semigeodesic coordinate system,Navier-Stokes equation on... In this paper,we proposal stream surface and stream layer.By using classical tensor calculus,we derive 3-D Navier-Stokes Equations(NSE)in the stream layer under semigeodesic coordinate system,Navier-Stokes equation on the stream surface and 2-D Navier-Stokes equations on a two dimensional manifold. After introducing stream function on the stream surface,a nonlinear initial-boundary value problem satisfies by stream function is obtained,existence and uniqueness of its solution are proven.Based this theory we proposal a new method called"dimension split method"to solve 3D NSE. 展开更多
关键词 STREAM layer STREAM surface 2D MANIFOLD NAVIER-STOKES equations dimen-sion SPLIT method.
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Assessment of Interannual Sea Surface Salinity Variability and Its Effects on the Barrier Layer in the Equatorial Pacific Using BNU-ESM 被引量:3
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作者 Hai ZHI Rong-Hua ZHANG +3 位作者 Fei ZHENG Pengfei LIN Lanning WANG Peng YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第3期339-351,共13页
As salinity stratification is necessary to form the barrier layer (BL), the quantification of its role in BL interannual variability is crucial. This study assessed salinity variability and its effect on the BL in t... As salinity stratification is necessary to form the barrier layer (BL), the quantification of its role in BL interannual variability is crucial. This study assessed salinity variability and its effect on the BL in the equatorial Pacific using outputs from Beijing Normal University Earth System Model (BNU-ESM) simulations. A comparison between observations and the BNU-ESM simulations demonstrated that BNU-ESM has good capability in reproducing most of the interannual features observed in nature. Despite some discrepancies in both magnitude and location of the interannual variability centers, the displacements of sea surface salinity (SSS), barrier layer thickness (BLT), and SST simulated by BNU-ESM in the equatorial Pacific are realistic. During E1 Nifio, for example, the modeled interannual anomalies of BLT, mixed layer depth, and isothermal layer depth, exhibit good correspondence with observations, including the development and decay of E1 Nifio in the central Pacific, whereas the intensity of the interannual variabilities is weaker relative to observations. Due to the bias in salinity simulations, the SSS front extends farther west along the equator, whereas BLT variability is weaker in the central Pacific than in observations. Further, the BNU-ESM simulations were examined to assess the relative effects of salinity and temperature variability on BLT. Consistent with previous observation-based analyses, the interannual salinity variability can make a significant contribution to BLT relative to temperature in the western-central equatorial Pacific. 展开更多
关键词 FEEDBACK interannual variability sea surface salinity barrier layer thickness
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