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Singular optical propagation properties of two types of one-dimensional anti-PT-symmetric periodic ring optical waveguide networks

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Chinese Physics B 2024年第3期33卷 355-362页

作者：樊阳龙杨湘波练华达陈润楷朱蓬勃邓冬梅刘宏展韦中超 Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China

Two types of one-dimensional(1D)anti-PT-symmetric periodic ring optical waveguide networks,consisting of gain and loss materials,are constructed.The singular optical propagation properties of these networks are investigated.The results show that the system composed of gain materials exhibits characteristics of ultra-strong transmission and bidirectional reflection.Conversely,the system composed of loss materials demonstrates equal transmittance and reflectance at some frequencies.In both the systems,a new type of total reflection phenomenon is observed.When the imaginary part of the refractive indices of waveguide segments is smaller than 10-5,the system shows bidirectional transparency with the transmittance tending to be 1 and reflectivity to be smaller than 10-8 at some bands.When the refractive indices of the waveguide segments are real,the system will be bidirectional transparent at the full band.These findings may deepen the understanding of anti-PT-symmetric optical systems and optical waveguide networks,and possess potential applications in efficient optical energy storage,ultra-sensitive optical filters,ultra-sensitive all-optical switches,integrated optical chips,stealth physics,and so on.

关键词： anti-PT-symmetric waveguide networks bidirectional transparent

Nanostructure designing and hybridizing of high-capacity silicon-based anode for lithium-ion batteries

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Progress in Natural Science:Materials International 2023年第1期33卷 16-36页

作者： Longzhi Li Yue deng Kunkun Hu Bangqiang Xu Nana Wang zhongchao Bai Xun Xu Jian Yang College of Mechanical and Electronic Engineering Shandong University of Science and Technology Institute for Superconducting and Electronic Materials University of Wollongong Innovation Campus Key Laboratory of Colloid and Interface Chemistry Ministry of Education School of Chemistry and Chemical Engineering Shandong University

Lithium-ion batteries have long been used in electronic products and electric vehicles, but their energy density is slowly failing to keep up with demand. Because of its extraordinarily high theoretical specific capacity, silicon is regarded as the most potential next-generation anode material for practical lithium-ion batteries. However, its unavoidable volume expansion issue can cause electrode deformation and loss of electrical contact during cycling,resulting in significant performance reduction. This work reviews and evaluates the modification measures of Si,SiO, and SiO2as anode materials in order to address the challenges that silicon-based anode materials encounter.We not only review their lithium storage mechanism, but also focus on nanostructure designing and hybridizing to improve the electrochemical performance of silicon-based anodes. The silicon-based anodes can exhibit exceptional capacity retention and excellent rate performance after structural optimization and hybridization,which will greatly facilitate their commercial application. Finally, we discuss our thoughts and recommendations for the future development of silicon-based materials.

关键词： Lithium-ion batteries Silicon-based anode Nanostructure designing Hybridizing

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海底沙波对潜器水动力性能的影响

中国舰船研究 2023年第1期18卷 89-98,123页

作者：李鹏国瑀秦洪德邓忠超哈尔滨工程大学水下机器人技术国家重点实验室黑龙江哈尔滨150001 哈尔滨工程大学烟台研究院山东烟台264006

[目的]研究潜器在海底沙波地形干扰下的水动力特性。[方法]基于计算流体力学(CFD)方法,使用STAR-CCM+软件并结合重叠网格方法对潜器经过海底沙波的过程进行模拟,计算潜器阻力系数和升力系数在此过程中的变化。[结果]结果表明,当潜器近... 详细信息

[目的]研究潜器在海底沙波地形干扰下的水动力特性。[方法]基于计算流体力学(CFD)方法,使用STAR-CCM+软件并结合重叠网格方法对潜器经过海底沙波的过程进行模拟,计算潜器阻力系数和升力系数在此过程中的变化。[结果]结果表明,当潜器近海底航行时,沙波地形会对潜器产生一定的干扰,当艏部运动至波峰附近时,负升力出现最大值,当艉部运动至波峰附近时,阻力出现最大值;在不同航速下,潜器表面压力分布规律的不同会导致升力系数的变化规律不同;随着近海底距离的减小,海底沙波对潜器阻力和升力变化影响显著,当H/D>5时,海底沙波对潜器阻力和升力的影响可以忽略。[结论]所做研究可为潜器的安全及操纵性能提供一定的参考。

关键词：潜器海底沙波水动力性能流场特性

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新型仿生鲨鱼结构设计及操纵性分析

Journal of Marine Science and Application 2022年第2期21卷 82-91页

作者：高立阳李鹏秦洪德邓忠超 College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China Yantai Research Institute and Graduate School of Harbin Engineering University Yantai 264006China

In this paper,the mechatronic design and maneuverability analysis of a novel robotic shark are presented.To obtain good maneuverability,a barycenter regulating device is designed to assist the posture adjustment at low speeds.Based on the Newton-Euler approach,an analytical dynamic model is established with particular consideration of pectoral fins for threedimensional motions.The hydrodynamic coefficients are computed using computational fluid dynamics(CFD)methods.Oscillation amplitudes and phases are determined by fitting an optimized fish body wave.The performance of the robotic shark is estimated by varying the oscillation frequency and offset angle.The results show that with oscillation frequency increasing,the swimming speed increases linearly.The robotic shark reaches the maximum swimming speed of 1.05 m/s with an oscillation frequency of 1.2 Hz.Furthermore,the turning radius decreases nonlinearly as the offset angle increased.The robotic shark reaches the minimum turning radius of 1.4 times the body length with 0.2 Hz frequency and 12°offset angle.In the vertical plane,as the pectoral fin angle increases,the diving velocity increases nonlinearly with increase rate slowing down.

关键词： Mechatronic design Three-joint propulsion system Robotic shark Dynamic modeling Maneuverability analysis

Multi-Channel FIR Laser Interferometer on the HL-2A Tokamak

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Southwestern Institute of Physics Annual Report 2004年第1期 28-30页

作者： deng zhongchao ZHOU Yan TANG Yiwu YI Jiang

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海底对无人水下航行器水动力性能的影响

船舶工程 2022年第4期44卷 146-153页

作者：李鹏国瑀秦洪德邓忠超哈尔滨工程大学船舶工程学院哈尔滨150001 哈尔滨工程大学烟台研究(生)院山东烟台264006

为了保证无人水下航行器(UUV)近海底作业时的安全性及作业效率,需要分析海底对UUV水动力性能的影响。基于计算流体力学(CFD)方法对UUV靠近海底时的水动力参数进行求解,通过数值模拟UUV近海底附近的流场,得到了UUV阻力系数和升力系数随... 详细信息

为了保证无人水下航行器(UUV)近海底作业时的安全性及作业效率,需要分析海底对UUV水动力性能的影响。基于计算流体力学(CFD)方法对UUV靠近海底时的水动力参数进行求解,通过数值模拟UUV近海底附近的流场,得到了UUV阻力系数和升力系数随雷诺数、距海底的距离和攻角3个参数的变化规律,并针对UUV受到的阻力、吸引力以及流场特性的变化进行具体分析。结果表明,在距离海底一定范围内,UUV受到的阻力和吸引力都会增大,吸引力更为明显,这为UUV的实际工作提供了一定指导。

关键词：无人水下航行器海底计算流体力学水动力性能流场特性

The Sawtooth Like Electron Density Oscillations under LBO and LHCD in HL-1M Tokamak

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中国核科技报告 1998年第S5期 3-5页

作者： JIAO Yiming ZHOU Yan deng zhongchao GAO Qingdi

Experiments of many Tokamaks have shown that the sawtooth oscillations of electron density can be used to study the particle behaviors of central plasma. Density sawteeth have been observed and studied on

关键词： Density sawtooth like oscillation LHCD Impurity

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基于近似模型理论的水上飞机浮筒优化设计

船舶工程 2022年第5期44卷 75-81,147页

作者：李鹏闵锴瑞秦洪德邓忠超哈尔滨工程大学船舶工程学院哈尔滨150001

以浮筒式水上飞机的浮筒为研究对象,以滑行阶段受到的水动阻力较小和产生较小水花溅射现象为最终目标,利用CAD建模软件CATIA实现对浮筒外形的模型建立,运用流体计算软件STAR-CCM+对浮筒在水上飞机水面滑行阶段时的水动力特征进行了数值... 详细信息

以浮筒式水上飞机的浮筒为研究对象,以滑行阶段受到的水动阻力较小和产生较小水花溅射现象为最终目标,利用CAD建模软件CATIA实现对浮筒外形的模型建立,运用流体计算软件STAR-CCM+对浮筒在水上飞机水面滑行阶段时的水动力特征进行了数值模拟计算。最后,应用近似模型优化方法,采用NSGA-II算法实现了浮筒横剖面和断阶处的多目标优化设计,并将所得结果与CFD计算结果进行了对比,验证了优化的可行性。

关键词：水上飞机浮筒水动力近似模型 NSGA-Ⅱ 优化设计

Zeff Derived from the Sawtooth-Performances in the Centre of Plasmas for Steady State Tokamak

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中国核科技报告 1999年第S3期 3-5页

作者： ZHENG Yongzhen DING Xuantong GUO Gancheng deng zhongchao

The mean effective ion charge, Zis an important parameter in the detailed description of the plasma performance in Tokamak discharges. This quantity is often derived from the bremsstrahlung radiation losses of the plasma, but may also be obtained from information on the electrical plasma resistivity. Here the procedure is applied in considering the relaxations of the central plasma region of Tokamak discharges immediately

关键词： Mean effective ion charge Sawtooth relaxation