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Nano Research 2022年第2期15卷 1486-1491页

作者： Xuanyi Li zhili zhu Qing Yang Zexian Cao Yeliang Wang Sheng Meng Jiatao Sun Hong-Jun Gao Institute of Physics and University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China School of Information and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing 100081China CAS Center for Excellence in Topological Quantum Computation Beijing 100049China BIT Chongqing Center for Microelectronics and Microsystems Chongqing 401332China

Two-dimensional(2D)magnetic crystals have been extensively explored thanks to their potential applications in spintronics,valleytronics,and topological *** we report a novel monolayer magnet,namely puckered pentagonal VTe_(2)(PP-VTe_(2)),intriguing atomic and electronic structures of which were firmly validated from first-principles *** PP-VTe_(2) exhibits strong intrinsic ferromagnetism and semiconducting property distinct from the half-metallic bulk pyrite VTe_(2)(BP-VTe_(2))*** unusual magnetic anisotropy with large magnetic exchange energies is *** interestingly,the multiferroic coupling between its 2D ferroelasticity and in-plane magnetization is further identified in PP-VTe_(2),lending it unprecedented controllability with external strains and electric *** as an emergent 2D ferromagnetic semiconductor with a novel crystal structure,monolayer PP-VTe_(2) provides an ideal platform for exploring exotic crystalline and spin configurations in low-dimensional systems.

关键词： first-principles puckered pentagonal VTe_(2) ferromagnetic semiconductor ferroelasticity

Goal Programming for Stable Mode Transition in Tandem Turbo-ramjet Engines

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Chinese Journal of Aeronautics 2009年第5期22卷 486-492页

作者： Chen Min Tang Hailong zhu zhili School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

This article, in order to guarantee the stable mode transition in tandem turbo-ramjet engines, investigates the multi-objective and multi-variable goal programming algorithm. First, it introduces the structural features of the variable cycle turbo-ramjet engines, the principles of selecting the mode transition operation point and the design parameters, and the characteristics of the turbofan mode and the ramjet mode. Second, a component-based variable cycle turbo-ramjet engine model is developed to simulate the mode transition process. Third, the Newton-Raphson algorithm is used to solve the multi-variable and multi-objective optimization problem. The results show that with the maximum residua of only 0.06%, this algorithm has an acceptable convergence that meets the predetermined goals. Finally, the simulation shows that the stable turbo-ramjet mode transition could be realized with the mode transition control law developed by the algorithm.

关键词： propulsion transition goal programming algorithm turbine-based combine cycle engine turbofan engine ramjetengine hypersonic

From atom to monatomic wire:an ab initio study of magnetism in 3d transition metals

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Acta Metallurgica Sinica(English Letters) 2010年第3期23卷 191-196页

作者： zhili zhu Jinhua GU Yu JIA Xing HU School of Physical Engineering and Material Physics Laboratory Zheng Zhou University Zhengzhou 450052 China

A systematic ab initio study on magnetism of the 3d transition metals（TM） from atom to monoatomic wire within density functional theory with generalized gradient approximation（GGA） was *** results show that the spin coupling has strong intraatomic exchange strengths about 1 eV for isolated 3d TM *** magnetic moments are distinctly lower than those of free atoms for all dimers except Mn 2 .All the 3d TM elements exhibit magnetic ground states in the linear wire structure.

关键词： Ab initio study Magnetism Transition metals

First principle study on the possibilities of magnetism in one-dimensional In and Tl atomic wires with the full-potential linearized augmented plane wave method

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Acta Metallurgica Sinica(English Letters) 2009年第2期22卷 117-122页

作者： zhili zhu Jinhua GU Yu JIA Xing HU School of Physical Engineering and Material Physics Laboratory Zheng Zhou University Zhengzhou 450052 China

Using ab initio total energy calculations with the full-potential linearized augmented plane wave method, the possibilities of magnetism in one-dimensional In and Tl wires were explored and their properties as the function of geometric structures were studied. The results suggest that the linear In and Tl wires show magnetization at the equilibrium bond distance with magnetic moments of 0.71 and 0.67 μB/atom, respectively. Allowing ions to relax, the wires were deformed as zigzag structures, but no dimerization occurs. The zigzag wires also exhibit spontaneous magnetization, although the magnetic moments are lower than those of straight wires.

关键词： Magnetism Atomic wire First-principle-study

Insight into the influence of high temperature annealing on the onset potential of Ti-doped hematite photoanodes for solar water splitting

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Chinese Chemical Letters 2018年第6期29卷 791-794页

作者： Yaodong zhu Qinfeng Qian Guozheng Fan zhili zhu Xin Wang Zhaosheng Li Zhigang Zou Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences Nanjing University

For Ti-doped hematite photoanodes, high temperature annealing drastically increases the water oxidation plateau photocurrent, but also induces an anodic shift of onset potential by about 100 m V, thus hindering the performance under low applied bias. To the best of our knowledge, the effects of high temperature annealing on the onset potential have been rarely studied. Herein, both X-ray photoelectron spectroscopy（XPS） measurements and theoretical calculations indicated that the increase of surface Ti/Fe atomic ratio after high temperature annealing decreased the adsorption capacity of hydroxide ions on the hematite surface. Subsequently, the flatband potential（i.e., the theoretical onset potential） of Ti doped hematite photoanodes positively shifted, which was supported by the Mott-Schottky measurements.

关键词： Onset potential Hematite Ti doping High temperature annealing Flatband potential DFT calculation

Line defects in monolayer TiSe_(2) with adsorption of Pt atoms potentially enable excellent catalytic activity

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Nano Research 2022年第5期15卷 4687-4692页

作者： Zhipeng Song Juxia Yi Jing Qi Qi Zheng zhili zhu Lei Tao Yun Cao Yan Li Zhaoyan Gao Ruizi Zhang Li Huang Geng Li Ziqiang Xu Xu Wu Yeliang Wang Chengmin Shen Yu-Yang Zhang Hongliang Lu Xiao Lin Shixuan Du Hong-Jun Gao Institute of Physics and University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

Two-dimensional(2D)materials with defects are desired for catalysis after the adsorption of monodispersed noble metal ***-performance catalysts with the absolute value of Gibbs free energy(|△GH|)close to zero,is one of the ultimate goals in the catalytic ***,we report the formation of monolayer titanium selenide(TiSe2)with line *** low-temperature scanning tunneling microscopy/spectroscopy(STM/S)measurements revealed the structure and electronic states of the line *** functional theory(DFT)calculation results confirmed that the line defects were induced by selenium vacancies and the STM simulation was in good agreement with the experimental ***,DFT calculations show that monolayer TiSe_(2) with line defects have good catalytic activity for hydrogen evolution reaction(HER).If the defects are decorated with single Pt atom,the HER catalytic activity will be enhanced dramatically(|△GH|=0.006 eV),which is much better than Pt metal(|△GH|=0.09 eV).Line defects in monolayer TiSe_(2)/Au(111)provide a wonderful platform for the design of high-performance catalysts.

关键词： line defects hydrogen evolution reaction monolayer titanium selenide(TiSe_(2)) scanning tunneling microscope density functionaltheorycalculation

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自适应循环发动机总体设计技术探讨

航空动力学报 2022年第10期37卷 2046-2058页

作者：陈敏张纪元唐海龙朱之丽北京航空航天大学能源与动力工程学院北京100191 北京航空航天大学航空发动机研究院北京102206

自适应循环发动机是下一代飞行器的重要候选动力装置。在简要介绍国内外研究进展之后,重点对目前开展的自适应循环发动机总体设计研究进行综述:首先介绍典型的自适应循环发动机总体性能方案及结构形式,然后讨论自适应循环发动机的性能... 详细信息

自适应循环发动机是下一代飞行器的重要候选动力装置。在简要介绍国内外研究进展之后,重点对目前开展的自适应循环发动机总体设计研究进行综述:首先介绍典型的自适应循环发动机总体性能方案及结构形式,然后讨论自适应循环发动机的性能收益和代价,并对未来的总体设计发展趋势进行展望。认为未来自适应循环发动机总体设计应在并行多/变维度、多学科优化体系下开展,考虑多源不确定性因素的影响,可引入混合维度仿真方法评估新颖部件技术特征,并结合飞行任务需求开展飞机/发动机的综合性能优化。

关键词：自适应循环发动机总体设计研究进展典型结构形式总体性能特征性能收益与代价

Shallowing interfacial carrier trap in transition metal dichalcogenide heterostructures with interlayer hybridization

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Nano Research 2021年第5期14卷 1390-1396页

作者： Xu Wu Jingsi Qiao Liwei Liu Yan Shao Zhongliu Liu Linfei Li zhili zhu Cong Wang Zhixin Hu Wei Ji Yeliang Wang Hongjun Gao School of Information and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing100081China Institute of Physics&University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing100190China Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of PhysicsRenmin University of ChinaBeijing100872China Center for Joint Quantum Studies and Department of Physics Tianjin UniversityTianjin300350China CAS Center for Excellence in Topological Quantum Computation Beijing100049China

With the unique properties,layered transition metal dichalcogenide(TMD)and its heterostructures exhibit great potential for applications in *** electrical performance,e.g.,contact barrier and resistance to electrodes,of TMD heterostructure devices can be significantly tailored by employing the functional layers,called interlayer *** the interface between different TMD layers,the dangling-bond states normally exist and act as traps against charge carrier *** this study,we propose a technique to suppress such carrier trap that uses enhanced interlayer hybridization to saturate dangling-bond states,as demonstrated in a strongly interlayer-coupled monolayer-bilayer PtSe2 *** hybridization between the unsaturated states and the interlayer electronic states of PtSe2 significantly reduces the depth of carrier traps at the interface,as corroborated by our scanning tunnelling spectroscopic measurements and density functional theory *** suppressed interfacial trap demonstrates that interlayer saturation may offer an efficient way to relay the charge flow at the interface of TMD ***,this technique provides an effective way for optimizing the interface contact,the crucial issue exists in two-dimensional electronic community.

关键词： transition metal dichalcogenide PtSe2 layered heterostructure band alignment strong interlayer interaction

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涡扇发动机地面起动过程性能模拟

北京航空航天大学学报 2006年第3期32卷 280-283页

作者：朱之丽高超北京航空航天大学能源与动力工程学院北京100083

用积分方法建立了混合排气加力涡扇发动机起动过程模拟模型并用该模型进行了仿真计算,模型基于气动热力学方程、各部件特性以及经验关系式,根据给出的发动机起动过程初始条件、燃烧室供油规律等进行计算.为说明所建立的起动性能模型的... 详细信息

用积分方法建立了混合排气加力涡扇发动机起动过程模拟模型并用该模型进行了仿真计算,模型基于气动热力学方程、各部件特性以及经验关系式,根据给出的发动机起动过程初始条件、燃烧室供油规律等进行计算.为说明所建立的起动性能模型的模拟效果,将程序计算结果与试验结果进行了比较,结果表明该起动仿真模型能较准确地模拟混排加力涡扇发动机的地面起动过程.还分析了计算过程中对起动过程有比较大影响的因素,包括计算时间步长,起动机脱开转速,燃烧室总压恢复系数的经验系数,大气温度、压力以及海拔高度等.了解这些因素对起动过程及模拟结果的影响,便于通过修正的途径将该计算方法用于发动机地面起动性能的准确模拟.

关键词：涡扇发动机起动模拟分析

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基于梯度搜索与进化机制的多目标混合算法

北京航空航天大学学报 2024年第6期50卷 1940-1951页

作者：诸才承唐智礼赵鑫曹凡南京航空航天大学航空学院南京210016

多目标进化算法(MOEA)因其良好的全局探索能力备受关注,但其在最优值附近的局部搜索能力却相对较弱,且对于具有大规模决策变量的优化问题,MOEA所需的种群数量与迭代次数都十分庞大,优化效率较低。基于梯度的优化算法能够很好地克服这些... 详细信息

多目标进化算法(MOEA)因其良好的全局探索能力备受关注,但其在最优值附近的局部搜索能力却相对较弱,且对于具有大规模决策变量的优化问题,MOEA所需的种群数量与迭代次数都十分庞大,优化效率较低。基于梯度的优化算法能够很好地克服这些问题,但梯度搜索算法很难应用于多目标问题(MOPs)。在加权平均梯度的基础上引入随机权函数,发展多目标梯度算子,将其与基于参考点的第三代非支配排序遗传算法(NSGA-Ⅲ)结合,发展了多目标梯度优化算法(MOGBA)和多目标混合进化算法(HMOEA)。HMOEA在保留NSGA-Ⅲ良好的全局探索能力的同时,极大地增强了局部搜索能力。数值实验表明:HMOEA对于各种Pareto阵面都具有优秀的捕获能力,与典型的多目标算法相比效率提升了5~10倍。进一步将HMOEA应用于RAE2822翼型的多目标气动优化问题中,得到了理想的Pareto前沿,表明HMOEA是一种高效的优化算法,在气动优化设计中具有潜在的应用价值。

关键词：多目标优化混合算法进化算法梯度方法气动优化

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