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Carbon-coated mesoporous Co9S8 nanoparticles on reduced graphene oxide as a long-life and high-rate anode material for potassium-ion batteries

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Nano Research 2020年第3期13卷 802-809页

作者： Guangyao Ma Xiao Xu Zhenyu Feng Chenjing Hu Yansong Zhu Xianfeng yang Jian yang Yitai Qian Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong UniversityJinan250100China Analytical and Testing Center South China University of TechnologyGuangzhou510640China Hefei National Laboratory for Physical Science at Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei230026China

Carbon-coated mesoporous Co9S8 nanoparticles supported on reduced graphene oxide(rGO)are successfully synthesized by a simple *** composite makes full use of the protection of the carbon layer on the surface,the good conductivity and three-dimensional(3D)structure of rGO,the mesoporous structure and nanoscale size of Co9S8,thereby presenting the excellent electrochemical performances in potassium-ion batteries,407.9 mAh·g^−1 after 100 cycles at 0.2 A·g^−1 and 215.1 mAh·g^−1 at 5 A·g^−1 in rate *** 1,200 cycles at 1.0 A·g^−1,this composite still remains a capacity of 210.8 mAh·g^−*** redox reactions for potassium storage are revealed by ex-situ transmission electron microscope(TEM)/high-resolution TEM(HRTEM)images,selected area electron diffraction(SAED)patterns and X-ray photoelectron spectroscopy(XPS)*** application of this composite as the host of sulfur for Li-S batteries is also *** sustains a capacity of 431.8 mAh·g^−1 after 800 cycles at 3 C,leading to a degradation of 0.052%per *** results confirm the wide applications of this composite for electrochemical energy storage.

关键词： sulfides graphene nanocomposite mesoporous structure potassium ion batteries

Neutral excitation and bulk gap of fractional quantum Hall liquids in disk geometry

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Chinese Physics B 2019年第6期28卷 20-26页

作者： Wu-Qing yang Qi Li Lin-Peng yang Zi-Xiang Hu Department of Physics Chongqing UniversityChongqing 401331China Department of Physics South University of Science and Technology of ChinaShenzhen 518055China School of Physics and Technology Wuhan UniversityWuhan 430072China

For the numerical simulation of the fractional quantum Hall(FQH) effects on a finite disk, the rotational symmetry is the only symmetry that is used in diagonalizing the Hamiltonian. In this work, we propose a method of using the weak translational symmetry for the center of mass of the many-body system. With this approach, the bulk properties, such as the energy gap and the magneto-roton excitation are consistent with those in the closed manifolds like the sphere and torus. As an application, we consider the FQH phase and its phase transition in the fast rotated dipolar fermions. We thus demonstrate the disk geometry having versatility in analyzing the bulk properties beside the usual edge physics.

关键词： fractional quantum Hall bulk states edge states magneto-roton dipolar–dipolar interaction

Nuclear clustering in light neutron-rich nuclei

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Nuclear Science and Techniques 2018年第12期29卷 112-127页

作者： yang Liu Yan-Lin Ye School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University

Clustering is a general phenomenon observed in light nuclei, especially in neutron-rich nuclei in which molecular configurations can be formed with various combinations of valence neutrons. Thus far, many theoretical models have been developed to describe nuclear clustering phenomena. These models are outlined in this review article, with an emphasis on their basic formulations and physical ingredients. In addition, various experimental tools, such as inelastic excitation and decay, transfer reactions, and resonant scattering reactions, have been applied to investigate the cluster structures inside the nucleus. Each tool possesses certain advantages and favorable applications, which are also described. In the case of neutron-rich nuclei, cluster structures may be configured as molecular states that form rotational bands with an extremely large moment of inertia and generate relatively large cluster decay width. The major experimental criteria for the identification of cluster formation are discussed herein.

关键词：轻原子核中子聚类转移反应簇结构物理成分应用程序试验性

Vote-Based Feature Selection Method for Stratigraphic Recognition in Tunnelling Process of Shield Machine

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 141-155页

作者： Liman yang Xuze Guo Jianfu Chen Yixuan Wang Huaixiang Ma Yunhua Li Zhiguo yang Yan Shi School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China China Railway 14th Bureau Group Mega Shield Construction Engineering Co. Ltd.Nanjing 211800China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Shield machines are currently the main tool for underground tunnel construction. Due to the complexity and variability of the underground construction environment, it is necessary to accurately identify the ground in real-time during the tunnel construction process to match and adjust the tunnel parameters according to the geological conditions to ensure construction safety. Compared with the traditional method of stratum identifcation based on staged drilling sampling, the real-time stratum identifcation method based on construction data has the advantages of low cost and high precision. Due to the huge amount of sensor data of the ultra-large diameter mud-water balance shield machine, in order to balance the identifcation time and recognition accuracy of the formation, it is necessary to screen the multivariate data features collected by hundreds of sensors. In response to this problem, this paper proposes a voting-based feature extraction method (VFS), which integrates multiple feature extraction algorithms FSM, and the frequency of each feature in all feature extraction algorithms is the basis for voting. At the same time, in order to verify the wide applicability of the method, several commonly used classifcation models are used to train and test the obtained efective feature data, and the model accuracy and recognition time are used as evaluation indicators, and the classifcation with the best combination with VFS is obtained. The experimental results of shield machine data of 6 diferent geological structures show that the average accuracy of 13 features obtained by VFS combined with diferent classifcation algorithms is 91%;among them, the random forest model takes less time and has the highest recognition accuracy, reaching 93%, showing best compatibility with VFS. Therefore, the VFS algorithm proposed in this paper has high reliability and wide applicability for stratum identifcation in the process of tunnel construction, and can be matched with a variety of

关键词： Shield machine Tunneling parameters Feature selection Stratigraphic recognition

Simultaneously enhanced heat dissipation and tribological properties of polyphenylene sulfide-based composites via constructing segregated network structure

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Journal of Materials Science & Technology 2022年第4期99卷 239-250页

作者： You Shi yang Bai Yanzhou Lei Haoruo Zhang Shengtai Zhou Huawei Zou Mei Liang yang Chen The State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China

Self-lubricating polyphenylene sulfide(PPS)composites were fabricated by constructing a segregated network structure using the co-deposition *** carboxyl-functionalized multi-walled carbon nanotubes(CNTs)and silicon carbide(SiC)were successfully coated on the surface of PPS powders with the aid of self-polymerization of dopamine(PDA)and co-polymerization between PDA and polyethyleneimine(PEI),thereby forming PPS@PDA-CNTs-SiC hierarchical reinforcing *** showed that the thermal conductivity of PPS@PDA-CNTs-SiC(0.97 W/(m K))is about 120%higher than that of PPS/CNTs/*** friction coefficient(0.193)and specific wear rate(2.50×10^(-5)mm^(3)/(N m))of PPS@PDA-CNTs-SiC are 18.9%and 50%lower than those of PPS/CNTs/SiC,*** enhanced thermal conductivity of PPS@PDA-CNTs-SiC contributes to rapid dissipation of frictional heat at the sliding interface which protects the polymer substrate from being destroyed or peeled,thereby improving the tribological *** work provides new insights into expanding the application of self-lubricating polymer composites in the fields where efficient heat dissipation is also a primary concern.

关键词： Polyphenylene sulfide Segregated network Thermal conductivity Self-lubricating polymer composites Transfer film

Influence of dc bias on amorphous carbon deposited by pulse laser ablation

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Rare Metals 2002年第4期21卷 294-298页

作者： yang Yimin, GUO Jian, CAI Mengqiu, and yang GuoweiDepartment of Physics, Xiangtan University, Xiangtan 411105, China Department of Physics Xiangtan University Xiangtan 411105

Amorphous carbon films were deposited on single-crystalline silicon and K9glass by pulse laser ablation using different negative substrate bias. Scanning electron microscope(SEM) was used to observe morphology of the surface. Thickness and refractive index of the filmdeposited on K9 glass were measured by ellipsometry. Micro-hardness of films was measured relativelyto single crystal silicon. All films deposited on silicon were analyzed by Raman spectra. Allspectra were deconvoluted to three peaks. Line-width ratios varied similarly with bias voltage whenthe laser energy was kept invariant.

关键词： negative substrate bias amorphous carbon laser ablation

Bifurcations and Chaos in Mira 2 Map

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 967-978页

作者： Tao JIANG Zhi-yan yang School of Information Beijing Wuzi University Beijing 101149 China

In this paper, Mira 2 map is investigated. The conditions of the existence for fold bifurcation, flip bifurcation and Naimark-Sacker bifurcation are derived by using center manifold theorem and bifurcation theory. And the conditions of the existence for chaos in the sense of Marroto are obtained. Numerical simulation results not only show the consistence with the theoretical analysis but also display complex dynamical behaviors, including period-n orbits, crisis, some chaotic attractors, period-doubling bifurcation to chaos, quasi-period behaviors to chaos, chaos to quasi-period behaviors, bubble and onset of chaos.

关键词： Mira 2 map fold bifurcation flip bifurcation Naimark-Sacker bifurcation chaos in the sense ofMarroto

Regular and p-Regular Orbits of Solvable Linear Groups,Ⅱ

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Algebra Colloquium 2023年第2期30卷 301-304页

作者： Thomas Michael Keller Yong yang Department of Mathematics Texas State UniversitySan MarcosTX 78666USA College of Science China Three Gorges University Three Gorges Mathematical Research CenterYichangHubei 443002China Department of MathematicsTexas State UniversitySan MarcosTX 78666USA

Let V be a faithful G-module for a finite group G and let p be a prime dividing IG].An orbit yG for the action of G on V is regular if|v^(G)|=|G:C_(G)(v)]=|G|,and is p-regular if|v^(G)|_(p)=|G:C_(G)(v)|_(p)=|G|_(p).In this note,we study two questions,one by the authors and one by Isaacs,related to the p-regular orbits and regular orbits of the linear group actions.

关键词： regular orbits solvable linear groups group action

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土工格栅在路基工程中的特殊应用

路基工程 2005年第4期 66-68页

作者：秦东风江苏省交通规划设计院上海200092

论述土工格栅的性能、功能及其在路基工程中的各种应用。

关键词：土工格栅路基工程抗拉强度加筋技术