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Enhancing electrochemical capacity and interfacial stability of lithium-ion batteries through side reaction modulation with ultrathin carbon nanotube film and optimized lithium cobalt oxide particle size

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Nano Research 2024年第8期17卷 7230-7241页

作者： Wei xi xiaogang xia Jiacheng Zhu Dehua Yang Sishen xie Beijing National Laboratory for Condensed Matter physics and Institute of physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Advanced Passivation Technology Lab College of Physics Science and TechnologyHebei UniversityBaoding 071002China

Lithium cobalt oxide(LCO),the first commercialized cathode active material for lithium-ion batteries,is known for high voltage and ***,its application has been limited by relatively low capacity and stability at high *** particle size is considered one of the most straightforward and effective strategies to enhance ion transfer,thus increasing the rate ***,side reactions are simultaneously enhanced as the specific surface area ***,we investigate the impact of LCO particles with varying size distributions and optimize the particle *** modulate the side reactions associated with particle size reduction,an ultrathin carbon nanotube film(UCNF)is introduced to coat the cathode *** this simple process and optimized particle size,the rate performance improves significantly,normal commercial LCO achieves 118 mA·h·g^(−1)at 3.0–4.3 V and 20 C(0.72 mA·h·cm^(−2)),corresponding to power density of 8732 W·kg^(−1).This method is applied to high voltage as well,152 mA·h·g^(−1)at 3.0–4.6 V and 20 C(0.99 mA·h·cm^(−2))was achieved with high-voltage LCO(HVLCO),corresponding to power density of 11,552 W·kg^(−1).The cycling stability is also enhanced,with the capacity retention maintaining more than 96%after 100 cycles at 0.1 *** the first time,UCNF is demonstrated to suppress the excessive decomposition of the electrolytes and solvents by blocking electron injection/extraction between LCO and electrolyte *** findings provide a simple method for improving LCO rate performance,especially at high C-rates.

关键词： lithium-ion batteries lithium cobalt oxides carbon nanomaterials side reactions

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Cenozoic volcanic rocks in the Belog Co area, Qiangtang, northern Tibet, china: Petrochemical evidence for partial melting of the mantle-crust transition zone

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Acta Geochimica 2007年第3期26卷 305-311页

作者： LAI Shaocong, QIN Jiangfeng, LI Yongfeng, and LIU xin State Key Laboratory of Continental Dynamics, Department of Geology, northwest university, xi’an 710069, china State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an China

Neogene volcanic rocks in the Belog Co area, Qiangtang, northern Tibet, are represented by a typical intermediate-basic and intermediate alkaline rock association, with latite-trachyte as the main rock type. The results of chemical analysis are: SiO2=52%–62%, Al2O3>15%, Na2O/K2O>1 and MgO3.30%. In addition, the volcanic rocks are LREE-enriched with LREE/HREE=10–13, (La/Yb)N=15–19, and show a weak negative Eu anomaly with δEu=0.71–0.89. The close relationship between Mg# and SiO2 and the co-variation of the magmatophile elements and ultra-magmatophile elements such as La/Sm-La and Cr-Tb indicate that this association of volcanic rocks is the product of comagmatic fractional crystallization. The rock association type and lower Sm/Yb values (Sm/Yb=3.23–3.97) imply that this association of volcanic rocks should have originated from partial melting of spinel lherzolite in the lithospheric mantle. On the other hand, the weak negative Eu anomaly and relative depletion in Nb, Ta and Ti reflect the features of terrigenous magma. So the Neogene Belog Co alkaline volcanic rocks should be the result of partial melting of the special crust-mantle transition zone on the Qinghai-Tibet Plateau.

关键词： major and trace elements Cenozoic volcanic rock mantle-crust transition zone Qinghai-Tibet Plateau

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煤自燃初期的反应机理研究

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燃料化学学报 2004年第6期32卷 652-657页

作者：石婷邓军王小芳文振翼西北大学化学系陕西西安710069 西安科技大学陕西西安710054

从实验得到的可能引起煤自燃的8个活性基团入手,提出了一系列简单煤分子模型,利用密度泛函DFT 6 31G对其完成了几何优化,计算了包括反应焓变、吉布斯自由能和活化能等,从热力学和动力学角度分析了计算结果。基于理论计算获得了煤活性基... 详细信息

从实验得到的可能引起煤自燃的8个活性基团入手,提出了一系列简单煤分子模型,利用密度泛函DFT 6 31G对其完成了几何优化,计算了包括反应焓变、吉布斯自由能和活化能等,从热力学和动力学角度分析了计算结果。基于理论计算获得了煤活性基团的活泼性次序,得出了煤自燃初期的反应机理主要是氧分子先进攻煤分子中的活性基团,产生活泼性很高的中间体,然后中间体进一步反应得到水或二氧化碳及其他反应产物,计算结果与实验基本符合。

关键词：煤活性基团活化能反应饥理

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A Note on Wigner Functions and *-Genvalue Equation

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Communications in Theoretical physics 2009年第4期51卷 605-608页

作者： JING Si-Cong LIN Bing-Sheng Department of modern physics,university of Science and Technology of china,Hefei 230026,china Department of modern physics University of Science and Technology of China Hefei 230026 China

In deformation quantization,static Wigner functions obey functional *-genvalue equation,which is equiv-alent to time-independent Schr■dinger equation in Hilbert space operator formalism of quantum *** equiv-alence is proved mostly for Hamiltonian with form H=（1/2）■;+V（■）[***,***.60（1964）581].In this note we generalize this proof to a very general Hamiltonian H（■,■）and give examples to support it.

关键词： Wigner function *-genvalue equation deformation quantization

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Constraints on the late Mesozoic regional angular unconformity in West Liaoning-North Hebei by LA-ICP-MS dating

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Progress in Natural Science:Materials International 2008年第11期18卷 1395-1402页

作者： Hong Zhang~(a,b,*) Wenmin Guo~a xiaoming Liu~b a College of Mechanical and Energy Engineering,Jiangsu Polytechnic university,Changzhou 213016,china b Key Laboratory of Continental Dynamics,Department of Geology,northwest university,xi’an 710069,china College of Mechanical and Energy Engineering Jiangsu Polytechnic University Changzhou 213016 China Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China

The angular unconformity between the Tuchengzi Formation and the Zhangjiakou Formation in the Chengde area is commonly regarded as the direct evidence of boundary between Jurassic and Cretaceous systems,and as the evidence of tectonic transformation interfaces in Mesozoic Era in the West Liaoning-North ***,the lower boundary age of the Zhangjiakou Formation in the Chengde was to be thought about 135 Myr in the *** on the detailed study and systematic sampling in Yixian-Beipiao,Lingy- uan,Chengde and Luanping areas in the field,the authors obtained the following isotopic ages by means of LA-ICP-MS dating:In the Lingyuan area,the Zhangjiakou Formation and the Yixian Formation are in angular unconformable contact;the age range of the Zhangjiakou Formation volcanic rock is from 133 to 130 Myr(seven samples),and that of the Yixian Formation volcanic rock is from 126 to 121 Myr(eleven samples).In the Luotuoshan of Chengde,the Tuchengzi Formation and the Zhangjiakou Formation are in angu- lar unconformable contact;the age at the lower Zhangjiakou Formation is about 124 Myr(one sample),which reflects that the age range of the lower Zhangjiakou Formation is from 129 to 124 Myr combined with the previous *** the Luanping basin,there is the larg- est sediment gap in upper Mesozoic,whose lower boundary age is confined in 131 to 130 *** the Yixian-Beipiao area,the second Member of the Yixian Formation,making up more than 3/4 thickness of the Yixian Formation,was formed in 126 to 119 Myr,and the age of the Yixian Formation at the bottom is about 132 ***,the upper boundary age of the Tuchengzi Formation is about 136 Myr in the West Liaoning-North Hebei *** on the above isotopic data combined with the geological characteristics in the field in the West Liaoning-North Hebei region,it reflects that there was a widespread tectonic event in the period of 136 to 126 Myr (mainly in 130-126 Myr)in the West Liaoning-North Hebei,and it formed the

关键词： Dating LA-ICP-MS Angular unconformity Interface of tectonic transformation West Liaoning-North Hebei

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Influence of in situ formed spinel in bonding phase on mechanical properties and air permeability of magnesia-chrome porous purging materials

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Journal of Iron and Steel Research International 2024年第6期31卷 1459-1472页

作者： Yi An Hao Liu Zhou-fu Wang Yan Ma xi-tang Wang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Magnesia-chrome porous purging plugs are crucial functional components to remove inclusions and stabilize the flow field during iron and steel ***,practical applications of magnesia-chrome porous purging materials are stil hampered by the poor scouring resistance to molten steel and unstable air permeability owing to their low mechanical properties and uncontrollable pore ***,the particle-packing type magnesiachrome porous purging materials reinforced by in situ formed spinel were prepared using fused magnesia-chrome particles and Al powders as major raw *** results show that in situ formed spinel solid solutions in bonding phase led to the decreased median pore size and increased pore surface fractal dimension from the reactions between Al powders and magnesia-chrome particles and along with high-temperature sintering,bonding between magnesia-chrome particles and the resultant mechanical properties of materials were greatly ***,the results of air permeability tests and polynomial ftting indicated that the formation of spinel solid solutions was the main contributing factor for controllable air permeability,and pressure drop of porous purging materials was positively correlated with surface fractal dimension of ***,the as-prepared porous purging materials added with 6 wt.%Al powders obtained the maximum cold crushing strength(54.2 MPa)and hot modulus of rupture(12.9 MPa)with median pore size of 24.06μm and ftting non-Darcian permeability coefficient of 0.97×10^(-6)m.

关键词： Magnesia Chrome porous purging material Metallic Al-Spinel Mechanical strength Air permeability

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(2+1)-Dimensional Electron Acoustic Solitary Waves in an Unmagnetized Collisionless Plasma with Vortex-Like Hot Electrons

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Communications in Theoretical physics 2007年第2期47卷 339-342页

作者： LIN Mai-Mai DUAN Wen-Shan Department of physics,northwest,Normal university,Lanzhou 730070,china Department of physics Northwest Normal University Lanzhou 730070 China

In this paper,(2+1)-dimensional electron acoustic waves (EAW) in an unmagnetized collisionless plasmahave been studied by the linearized method and the reductive perturbation technique,*** dispersionrelation and a modified Kadomtsev Petviashvili (KP) equation have been obtained for the EAW in the plasma consideringa cold electron fluid and a vortex-like hot *** is found from some numerical results that the parameter β (theratio of the free hot electron temperature to the hot trapped electron temperature) effects on the amplitude and thewidth of the electron acoustic solitary waves (EASW).It can be indicated that the free hot electron temperature andthe hot trapped electron temperature have very important effect on the characters of the propagation for the EASW.

关键词： electron acoustic solitary wave vortex-like hot electrons reductive perturbation method

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Oscillographic Chronopotentiometry with High and Low Frequency Current

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Chinese Chemical Letters 2000年第5期11卷 443-446页

作者： Jian Bin ZHENG xiu Qi ZHANG Hong GAO (Institute of Electroanalytical Chemistry. northwest university.xi’an 710069) Inst. of Electroanalytical Chemistry Northwest University Xi'an 710069 China

A novel electroanalytical method. oscillographic chronopotentiometry with high and low frequency current. is presented in this paper. With this method, the sensitivity or almost all kinds of oscillographic chronopoten... 详细信息

关键词： stripping on-line preconcentration oscillographic chronopotentiometry

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Effects of hot deformation and in-situ ZrB2 particle on microstructure and tensile performance of AA7085 composite sheets

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Journal of Iron and Steel Research International 2024年第7期31卷 1778-1791页

作者： Jiang-jing Wu xi-zhou Kai Chuang Guan Yu-tao Zhao School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To provide a new idea to reduce anisotropy for sheets in the thickness direction by microstructure modification and,mean-while,maintain or even enhance tensile performance,the in-situ ZrB2 particle/AA7085 composite sheets with thicknesses of 1,2,3,and 6 mm were *** as-cast grain size was significantly refined by the heterogeneous nucleus of the ZrB2 *** microstructure results show that severe hot deformation converts as-cast disordered microstructure into a sequential microstructure by crushing the remanent phases and matrix into a fiber *** the solid solution and aging heat treatment,the composite sheets exhibit largely recrystallized grains compared with partially recrystallized grains in the matrix sheets,and weak or even free texture exists in the *** grain size in the composite sheets decreases with the increase in thickness *** the thickness range of 1-3 mm,the composite sheets maintain a similar tensile per-formance as that in matrix sheets,while the strength and ductility in the 6-mm-thick composite sheet are improved.

关键词： Composite sheet Grain structure Texture Dislocation Strengthening

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A digital twins enabled underwater intelligent internet vehicle path planning system via reinforcement learning and edge computing

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Digital Communications and Networks 2024年第2期10卷 282-291页

作者： Jiachen Yang Meng xi Jiabao Wen Yang Li Houbing Herbert Song School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Security and Optimization for Networked Globe Laboratory(SONG Lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA

The Autonomous Underwater Glider(AUG)is a kind of prevailing underwater intelligent internet vehicle and occupies a dominant position in industrial applications,in which path planning is an essential *** to the complexity and variability of the ocean,accurate environment modeling and flexible path planning algorithms are pivotal *** traditional models mainly utilize mathematical functions,which are not complete and *** existing path planning algorithms depend on the environment and lack *** overcome these challenges,we propose a path planning system for underwater intelligent internet *** applies digital twins and sensor data to map the real ocean environment to a virtual digital space,which provides a comprehensive and reliable environment for path *** design a value-based reinforcement learning path planning algorithm and explore the optimal network structure *** path simulation is controlled by a closed-loop model integrated into the terminal vehicle through edge *** integration of state input enriches the learning of neural networks and helps to improve generalization and *** task-related reward function promotes the rapid convergence of the *** experimental results prove that our reinforcement learning based path planning algorithm has great flexibility and can effectively adapt to a variety of different ocean conditions.

关键词： Digital twins Reinforcement learning Edge computing Underwater intelligent internet vehicle Path planning

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