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All-Electric Aircraft Nose Wheel Steering System with Two Worm Gears

Transactions of Nanjing University of Aeronautics and Astronautics 2018年第1期35卷 170-180页

作者： Zhang Ming Li Chuang Wu Xin Zhu Yin Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics&AstronauticsNanjing 210016P.R.China Shanghai Aircraft Design and Research Institute Shanghai 201210P.R.China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing 211106P.R.China

As all-electric aircraft has many advantages,an aircraft nose wheel steering system would be developed to the all-electric *** the control demand of the nose wheel steering system,based on the basic principles of nose wheel steering system and the design technique of mechanotronics,an all-electric aircraft nose wheel steering system,composed of a nose wheel steering mechanism of two worm gear and a control servo system of fly-by-wire with both steering and anti-shimmy functions is designed to meet the demand for operation control in the nose wheel steering ***,based on the LMS-AMESim software,the simulation model of the system is established to simulate the dynamics for the verification of its steering *** simulation results indicate that the nose wheel steering system is reasonable,and can meet the requirements of the general ***,the prototypes of the steering mechanism and control system are studied to validate the design,and the steering test bench is prepared to test the designed *** test results,such as steer angle,rotate speed of motor are analyzed in details and compared with the theoretical *** analysis and comparison results show that the design is reasonable and the property of the prototype can achieve the design objectives.

关键词： mechanotronics design nose wheel steering system all-electric aircraft design landing gear

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Deformation and fracture of long term creep of notched specimen of a single crystal nickel base super alloy 14

Deformation and fracture of long term creep of notched speci...

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14th International Conference on Fracture, ICF 2017

作者： Li, Ying Zhang, Ming Zong, Bin Yu, Hui-Chen Aviation Key Laboratory of Science and Technology on Aeronautical Materials and Evaluation Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials Beijing100095 China

Creep rupture life behavior of a nickel base superalloy of DZ125 was studied with respect to specimens with different notch shape under elevated temperature of *** result showed that the specimen with notch in the gauge length had a substantially longer life than that of specimen without notch, the bigger the stress concentration factor of Kt is, the longer creep rupture life the specimen exhibited. The SEM observation and analysis on the fractured specimen after text showed that microholes resulting in the damage of the specimen originated mostly from the central portion or portion other than boundary. Analysis was made of the stress distribution of the specimen with different shapes during test, based on which the stress rupture life of the specimen with different Kt values was normalized and a good consistency was found among the stress rupture life. © 2017 Chinese Society of Theoretical and Applied Mechanics. All Rights Reserved.

关键词： Stress concentration

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An architecture decomposition method of pneumatic catapult system based on OPM and DSM

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Chinese Journal of Aeronautics 2023年第8期36卷 168-181页

作者： Lu GAN Gang YANG Xianhui LI Enze ZHU Hu CHEN Xiaohui WEI State Key Laboratory of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of General Aviation and Flight Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The architecture strategy of the Unmanned Aerial Vehicle(UAV)pneumatic launch system should continue to evolve to adapt to complex and variable operating *** representation,decomposition perspective,and cluster analysis play a vital role in the early phase of system architecture *** order for the system to emerge anticipated and desirable intrinsic functional properties,an architecture decomposition method based on the ObjectProcess Methodology(OPM)and Design Structure Matrix(DSM)is put forward in this *** OPM is proposed to model the UAV launch process formally,and the matrix representation of the architecture of the pneumatic launch system is *** the extension of the definition and operations of DSM,with the Idicula-Gutierrez-Thebeau Algorithm plus(IGTA+)clustering algorithm,the transformation of the pneumatic launch system architecture from process decomposition to function decomposition is demonstrated in this *** analysis shows that the architecture decomposition of the pneumatic launch system meets the functional requirements of stakeholders.

关键词： Architecture decomposition Cluster analysis Design structure matrix Object-process methodology Pneumatic catapult system

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Composition-dependent micro-structure and photocatalytic performance of g-C_(3)N_(4) quantum dots@SnS2 heterojunction

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Nano Research 2021年第11期14卷 4188-4196页

作者： Sheng-Qi Guo Haijun Zhang Zhenzhong Hu Mengmeng Zhen Bo Yang Boxiong Shen Fan Dong Tianjin Key Laboratory of Clean Energy and Pollutant Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China Center for Aircraft Fire and Emergency Department of Safety EngineeringCivil Aviation University of ChinaTianjin300300China Yangtze Delta Region Institute(Huzhou) &Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaHuzhou313001China Institute of Advanced Technology University of Science and Technology of ChinaHefei230088China

Semiconductor combination is one of the most common strategies to obtain high-efficiency photocatalysts;however, the effect mechanism of composition ratio on micro-structure and photocatalytic activity is remaining unclear. In this study, a case of g-C_(3)N_(4) quantum dots@SnS_(2) (CNQDn@SnS_(2)) heterojunction with different ratio of CNQD is used to uncover the origin of optimum and excess composition for photocatalysts. Research on the functional mechanism of the optimum composition shows that 0.8 wt.% CNQD are completely attached to the non-(001) facets of SnS_(2), which benefits the formation of type-II heterojunction, resulting in an optimal pollutant degradation and mineralization efficiency. For the excess composition, both experiments and theoretical calculations confirm that excess CNQD (the part exceeding of 0.8 wt.%) located on the (001) facet of SnS_(2), leading to the type-I band alignment of this heterojunction, which severely restricts the separation of photo-induced charge carriers, and thus reduces their lifetime. This work makes the functional mechanism of composition ratio on micro-structure and photocatalytic activity clearer. Related research results provide a new insight into semiconductor combination study and take an important step toward the rational design of highly active photocatalysts.

关键词： heterojunction semiconductor combination composition ratio photocatalyst functional mechanism

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Review of electrochemical degradation of phenolic compounds

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International Journal of Minerals,Metallurgy and Materials 2021年第9期28卷 1413-1428页

作者： You Xue Xi Hu Qian Sun Hong-yang Wang Hai-long Wang Xin-mei Hou Beijing Advanced Innovation Center for Materials Genome Engineering Collaborative Innovation Center of Steel TechnologyUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation Chinese Academy of Environmental PlanningBeijing 100012China School of Materials Science Engineering Zhengzhou UniversityZhengzhou 450001China

Phenolic compounds are widely present in domestic and industrial sewage and have serious environmental *** oxidation(EO)is one of the most promising methods for sewage degradation because of its high efficiency,environmental compatibility,and *** this work,we present an in-depth overview of the mechanism and factors affecting the degradation of phenolic compounds by *** particular,the effects of treatment of phenolic compounds with different anode materials are discussed in *** non-active anode shows higher degradation efficiency,less intermediate accumulation,and lower energy consumption than the active *** combined with other treatment methods(biological,photo,and Fenton)presents advantages,such as low energy consumption and high degradation ***-while,the remaining drawbacks of the EO process in the phenolic compound treatment system have been ***,future re-search directions are put forward to improve the feasibility of the practical application of EO technology.

关键词： electrochemical oxidation phenolic compounds degradation mechanism anode material

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Interpretable machine-learning strategy for soft-magnetic property and thermal stability in Fe-based metallic glasses

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npj Computational Materials 2020年第1期6卷 1-9页

作者： Lu, Zhichao Chen, Xin Liu, Xiongjun Lin, Deye Wu, Yuan Zhang, Yibo Wang, Hui Jiang, Suihe Li, Hongxiang Wang, Xianzhen Lu, Zhaoping Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing100083 China Institute of Applied Physics and Computational Mathematics Beijing100088 China Software Center for High Performance Numerical Simulation Chinese Academy of Engineering Physics Beijing100088 China Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China

Fe-based metallic glasses (MGs) have been extensively investigated due to their unique properties, especially the outstanding soft-magnetic properties. However, conventional design of soft-magnetic Fe-based MGs is heavily relied on "trial and error" experiments, and thus difficult to balance the saturation flux density (Bs) and thermal stability due to the strong interplay between the glass formation and magnetic interaction. Herein, we report an eXtreme Gradient Boosting (XGBoost) machine-learning (ML) model for developing advanced Fe-based MGs with a decent combination of Bs and thermal stability. While it is an attempt to apply ML for exploring soft-magnetic property and thermal stability, the developed XGBoost model based on the intrinsic elemental properties (i.e., atomic size and electronegativity) can well predict Bs and Tx (the onset crystallization temperature) with an accuracy of 93.0% and 94.3%, respectively. More importantly, we derived the key features that primarily dictate Bs and Tx of Fe-based MGs from the ML model, which enables the revelation of the physical origins underlying the high Bs and thermal stability. As a proof of concept, several Fe-based MGs with high Tx (>800 K) and high Bs (>1.4 T) were successfully developed in terms of the ML model. This work demonstrates that the XGBoost ML approach is interpretable and feasible in the extraction of decisive parameters for properties of Fe-based magnetic MGs, which might allow us to efficiently design high-performance glassy materials. © 2020, The Author(s).

关键词： Thermodynamic stability

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Tuning the oxidation state of Ru to surpass Pt in hydrogen evolution reaction

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Nano Research 2021年第11期14卷 4321-4327页

作者： Rongpeng Ma Ying Wang Guoqiang Li Long Yang Shiwei Liu Zhao Jin Xiao Zhao Junjie Ge Wei Xing State Key Laboratory of Electroanalytical Chemistry Laboratory of Advanced Power SourcesChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China State Key Laboratory of Automotive Simulation and Control School of Materials Science and Engineering Key Laboratory of Automobile Materials of MOEJilin UniversityChangchun130012China

The high price of state-of-the-art Pt electrocatalysts has plagued the acidic water electrolysis technique for decades. As a cheaper alternative to Pt, ruthenium is considered an inferior hydrogen evolution reaction (HER) catalyst than Pt due to its high susceptibility to oxidation and loss of activity. Herein, we reveal that the HER activity on Ru based catalysts could surpass Pt via tuning Ru oxidation state. Specifically, RuP clusters encapsulated in few layers of N, P-doped carbon (RuP@NPC) display a minimum over potential of 15.6 mV to deliver 10 mA·cm^(−2). Moreover, we for the first time show that a Ru based catalyst could afford current density up to 4 A·cm^(−2) in a practical water electrolysis cell, with voltage even lower than the Pt/C-based cell, as well as high robustness during 200 h operation. Using a combination of experiment probing and calculation, we postulate that the suitably charged Ru (∼ +2.4) catalytic center is the origin for its superior catalytic behavior. While the moderately charged Ru is empowered with optimized H adsorption behavior, the carbon encapsulation layers protect RuP clusters from over oxidation, thereby conferring the catalyst with high robustness.

关键词： RuP clusters Ru oxidation state hydrogen evolution encapsulating/confining layers

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Effects of aging temperature on the microstructure and mechanical properties of a Ti2AlNb based alloy

Effects of aging temperature on the microstructure and mecha...

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Chinese Materials Conference on Special and High Performance Structural Materials, CMC 2015

作者： Zhou, Yi Cao, Jingxia Huang, Xu Wang, Bao Mi, Guangbao Beijing Institute of Aeronautical Materials Beijing100095 China Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys Beijing100095 China

ISBN: (纸本)9783038357612

Effects of aging temperature on microstructure and room temperature mechanical properties of solid solution treated Ti2AlNb based alloy have been investigated. The experimental results showed that after solution treatment and subsequently aging at different temperatures, all the alloys had β/B2, α2 and O three phases, which formed a typical bimodal microstructure with primary α2/O particles and acicular O precipitates dispersing within β/B2 matrix. With increasing the aging temperature, the acicular O precipitates decreased in amount but slightly increased in dimension;the particle α2/O phase did not change in amount but varied in structure, which changed into a core-shell morphology with an α2 core and a rim-O shell, and the rim-O shell was thickened;the change of microstructure led to the decrease in room temperature strength while slight improvement in plasticity. During the tension test, the cracks prefered to propagate along the prior β/B2 grain boundaries which were weaken by the necklace primary α2/O particles. © 2016 Trans Tech Publications, Switzerland.

关键词： Ternary alloys

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Revealing the Local Microstates of Fe–Mn–Al Medium Entropy Alloy:A Comprehensive First-principles Study

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Acta Metallurgica Sinica(English Letters) 2021年第11期34卷 1492-1502页

作者： Ying Zhang William Yi Wang Chengxiong Zou Rui Bai Yidong Wu Deye lin Jun Wang Xidong Hui Xiubing Liang Jinshan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China CAEP Software Center for High Performance Numerical Simulation Beijing 100088China Defense Innovation Institute Academy of Military Sciences of the PLA of ChinaBeijing 100071China

Entropy-stabilized multi-component alloys have been considered to be prospective structural materials attributing to their impressive mechanical and functional *** local chemical complexions,microstates and configurational transformations are essential to reveal the structure–property relationship,thus,to promote the development of advanced multicomponent *** the present work,effects of local lattice distortion(LLD)and microstates of various configurations on the equilibrium volume(V0),total energy,Fermi energy,magnetic moment(μMag)and electron work function(Φ)and bonding structures of the Fe–Mn–Al medium entropy alloy(MEA)have been investigated comprehensively by first-principles *** is found that theΦandμMag of those MEA are proportional to the V 0,which is dominated by lattice *** terms of bonding charge density,both the strengthened clusters or the so-called short-range order structures and the weakly bonded spots or weak spots are *** the presence of weakly bonded Al atoms implies a large LLD/mismatch,the Fe–Mn bonding pairs result in the formation of strengthened clusters,which dominate the local microstates and the configurational *** variations ofμMag are associated with the enhancement of the nearest neighbor magnetic Fe and Mn atoms,attributing to the LLD caused by Al atoms,the local changes in the electronic *** work provides an atomic and electronic insight into the microstate-dominated solid-solution strengthening mechanism of Fe–Mn–Al MEA.

关键词： Medium entropy alloy Bonding charge density Magnetic moment Microstates

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Anisotropic and mutable magnetization in Kondo lattice CeSb2

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Chinese Physics B 2017年第6期26卷 319-323页

作者：张云朱燮刚胡丙锋谭世勇谢东华冯卫刘琴张文刘瑜宋海峰罗丽珠张政军赖新春 Science and Technology on Surface Physics and Chemistry Laboratory Department of Engineering Physics Tsinghua University Key Laboratory of Neutron Physics Institute of Nuclear Physics and ChemistryChina Academy of Engineering Physics Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Software Center for High Performance Numerical Simulation China Academy of Engineering Physics Key Laboratory of Advanced Materials (MOE) School of Materials Science and EngineeringTsinghua University

We have systematically studied the behaviors of the resistivity and magnetization of CeSb2 single crystals as a function of temperature and external field. Four anomalies in the resistivity/magnetization-versus-temperature curves are observed at low magnetic field. They are located at 15.5 K, 11.5 K, 9.5 K, and 6.5 K, corresponding to the paramagnetic–magnetically ordered state（MO）, MO-antiferromagnetic（AFM）, AFM–AFM, and AFM–ferromagnetic（FM） transitions, *** anomaly at 9.5 K is only visible with H‖[010] by magnetic susceptibility measurements, indicating that the AFM–AFM transition only happens along [010] direction in ab-plane. The four magnetic transitions are strongly suppressed by high external field. Finally, the field-temperature phase diagrams of CeSb2 with different orientations of the applied field in ab-plane are constructed and indicate the highly anisotropic nature of the magnetization of CeSb2.

关键词： CeSb2 electronic properties magnetic properties

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