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Acta Metallurgica Sinica(English Letters) 2020年第7期33卷 947-956页

作者： Ning Li Cun-Lei Jia Zhi-Wei Wang Li-Hui Wu Ding-Rui Ni Zheng-Kun Li Hua-Meng Fu Peng Xue Bo-Lv Xiao Zong-Yi Ma Yi Shao yun-long chang School of Material Science and Engineering Shenyang University of TechnologyShenyang 110870China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

High-entropy alloys(HEAs) are a new class of materials with a potential engineering application,but how to obtain ultrafine or nano-sized crystal structures of HEAs has been a ***,we first presented an equiatomic CoCrFeNiCu HEA with excellent mechanical properties obtained via friction stir processing(FSP).After FSP,the Cu element segregation in the cast CoCrFeNiCu HEA was almost eliminated,and the cast coarse two-phase structure(several micrometers) was changed into an ultrafine-grained single-phase structure(150 nm) with a large fraction of high-angle grain boundaries and nanoscale deformation *** unique microstructure was mainly attributed to the severe plastic deformation during FSP,and the sluggish diffusion effect in dynamics and the lattice distortion effect in crystallography for ***,FSP largely improved the hardness and yield strength of the CoCrFeNiCu HEA with a value of 380 HV and more than 1150 MPa,respectively,which were> 1.5 times higher than those of the base *** great strengthening after FSP was mainly attributed to the significant grain refinement with large lattice distortion and *** study provides a new method to largely refine the microstructure and improve the strength of cast CoCrFeNiCu HEAs.

关键词： grain microstructure deformation

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壁面性质对蛇形微通道流动特性的影响

原子能科学技术 2017年第1期51卷 27-32页

作者：周云龙常赫东北电力大学能源与动力工程学院吉林省吉林市132012

采用CLSVOF方法,以空气和水为介质,对不同壁面性质的矩形截面蛇形微通道内气液两相流动进行模拟研究。验证模型的合理性后,改变粗糙度及雷诺数Re,讨论其对泊肃叶数Po和努塞尔数Nu的影响并分析其影响机制;改变壁面接触角及粗糙度,探讨其... 详细信息

采用CLSVOF方法,以空气和水为介质,对不同壁面性质的矩形截面蛇形微通道内气液两相流动进行模拟研究。验证模型的合理性后,改变粗糙度及雷诺数Re,讨论其对泊肃叶数Po和努塞尔数Nu的影响并分析其影响机制;改变壁面接触角及粗糙度,探讨其对微通道内流体流动的综合影响;由于蛇形微通道特有的回转弯道,针对几种具有不同壁面性质的通道组合情况对流体流动特性进行研究。计算结果表明,壁面粗糙度的增加对Po的影响高于Nu,且可强化传热;壁面粗糙度对亲水壁面与疏水壁面的影响效果相反;当直微通道为亲水性光滑壁面、回转弯道为疏水性粗糙壁面时,其传热效果更好。

关键词：蛇形微通道气液两相流数值模拟微流体学

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蛇形微通道气液两相流型的数值研究

高校化学工程学报 2016年第5期30卷 1067-1073页

作者：周云龙常赫东北电力大学能源与动力工程学院吉林吉林132012

采用CLSVOF(coupled level set and volume of fluid)方法,以空气和水为介质对矩形截面蛇形微通道内气液两相流动进行模拟研究。验证模型的合理性后,系统地研究了表面张力,液相黏度,壁面接触角及通道截面形状对蛇形微通道内不同流型间... 详细信息

采用CLSVOF(coupled level set and volume of fluid)方法,以空气和水为介质对矩形截面蛇形微通道内气液两相流动进行模拟研究。验证模型的合理性后,系统地研究了表面张力,液相黏度,壁面接触角及通道截面形状对蛇形微通道内不同流型间转换界限的影响,并绘制了不同表面张力、液相黏度及接触角下的流型图。最后,将计算结果与相同当量直径不同截面微通道内两相流流型图进行对比,分析截面形状及高宽比对流型间转换界限的影响。这些基本规律为微通道的系统设计提供了一定依据。

关键词：蛇形微通道气液两相流数值模拟流型微流体学

Status analysis on sputtering and erosion evaluation methods of ion optic systems

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Chinese Journal of Aeronautics 2025年第1期38卷 254-270页

作者： long MIAO Tongxun YANG Zhengxi ZHU chang LU Zhiwen WU Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China Advanced Aerospace Power and Energy Research Center Beijing Institute of TechnologyZhuhai 519088China

In the past few decades,ion engines have been widely used in deep-space propulsion and satellite *** aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion *** one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming *** this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid *** advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are *** different types of experimental methods of grid assembly erosion patterns are *** analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid ***,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime.

关键词： Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation

Underground laboratories·Deep underground observation·Scientific questions——Insights from observations of multi-physic fields in deep underground labs

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Science China Earth Sciences 2025年第2期68卷 343-362页

作者： Huiqi REN yun WANG chang CHEN Guangyu FU longqing QIU Lianghui GUO Chengliang XIE Yongsheng HE Heping SUN Jiwen TENG Institute of Defense Engineering Academy of Military SciencesBeijing 100850China State Kay Laboratory of Geological Processes and Mineral Resources Key Laboratory of Intraplate Volcanoes and EarthquakesMinistry of EducationChina University of Geosciences(Beijing)Beijing 100083China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan 430077China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

This paper presents a comprehensive review on recent development and research conducted in domestic and international underground laboratories. We first introduce the differences in three environments—surface, mountain tunnel cavities and underground coal mine tunnels—by examining cosmic ray background, ambient noises related to gravity and seismic measurement, and electromagnetic noises in magnetic and magnetotelluric measurements. We highlight potential misuse of the term Underground Lab or Deep Underground Lab when describing observations in different physical fields. We introduce unique features of underground coal mine tunnels in China, such as large spaces, ultra-quiet conditions, and ultra-clean environments. When comparing with mountain tunnel cavities and borehole observations, coal mine tunnel observations have superior long-term stability and high precision. Through observations and comparisons of multi-physic fields at surface and the deep underground, we find that the higher SNR seismic observations conducted in deep underground tunnels in coal mines are beneficial to improve velocity tomography of the solid earth. The gravity observation with a Superconducting Quantum Interference Device(SQUID) makes it possibly to capture slow earthquake, which has not been observed previously in the Chinese mainland. SQUID magnetic observations can detect fluctuations as weak as femto-Tesla(fT), enabling us to explore the attenuation of Schumann Resonance down to the solid Earth. This opens opportunities to investigate the connections between the Earth's magnetic field and the interactions within the human brain and heart. To improve the precision of quantum measurement,we should consider the possible effects of weak magnetic disturbances in deep underground environments. Finally, we discuss the importance of deep underground laboratories, observing facilities and techniques deployed in these laboratories, and their possible connection with respect to “deep space” an

关键词： Deep underground Multi-physic fields Super-high precision Slow earthquake Schumann Resonance Quantum measurement

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加砂玻璃钢管道性能及在火电工程中的应用

辽宁化工 2002年第1期31卷 38-41页

作者：运长龙王虹辽宁电力勘测设计院辽宁沈阳110000

通过加砂玻璃钢管道在火电工程中的成功应用 ,介绍了加砂玻璃钢管道的材质、设计。

关键词：加砂玻璃钢管道性能应用火电工程

Omnidirectional simulation analysis of thermomechanical coupling mechanism in inertia friction welding of Ni-based superalloy

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Chinese Journal of Aeronautics 2025年第1期38卷 202-216页

作者： chang-an LI Guoliang QIN Hao WANG School of Materials Science and Engineering Shandong UniversityJinan 250061China

The coupling between heat and pressure is the kernel of inertia friction welding(IFW)and is still not fully understood.A novel 3D fully coupled finite element model based on a plastic friction pair was developed to simulate the IFW process of a Ni-based superalloy and reveal the omnidirectional thermo-mechanical coupling mechanism of the friction *** numerical model successfully simulated the deceleration,deformation processes,and peak torsional moments in IFW and captured the evolution of temperature,contact pressure,and *** simulated results were validated through measured thermal history,optical macrography,and axial *** results indicated that interfacial friction heat was the primary heat source,and plastic deformation energy only accounted for 4%of the *** increase in initial rotational speed and friction pressure elevated the peak temperature,reaching a maximum of 1525.5K at an initial rotational speed of 2000 r/min and friction pressure of 400 *** interface heat generation could form an axial temperature gradient exceeding 320K/*** radial inhomogeneities of heat generation and temperature were manifested in a concentric ring distribution with maximum heat flux and temperature ranging from 2/5 to 2/3 *** radial inhomogeneities were caused by increasing linear velocity along the radius and an opposite distribution of contact pressure,which could reach 1.7 times the set pressure at the *** circumferential inhomogeneity of thermomechanical distribution during rotary friction welding was revealed for the first time,benefiting from the 3D *** deflection and transformation of distribution in contact pressure and Mises stress were indicators of plastic deformation and transition of quasi-steady state *** critical Mises stress was 0.5 times the friction pressure in this *** presented modeling provides a reliable insight into the thermo-mechanical coupling mechanism of IFW and lays a solid found

关键词： Inertia friction welding Thermo-mechanical coupling Inhomogeneity Numerical simulation Ni-based superalloy

Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time

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Chinese Journal of Aeronautics 2025年第1期38卷 491-506页

作者： Hao YOU Xinlong chang Jiufen ZHAO Rocket Force University of Engineering Xi’an 710025China

To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance ***,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact ***,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the ***,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy ***,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering ***,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law.

关键词： Three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode

A Dynamic Social Network Graph Anonymity Scheme with Community Structure Protection

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Computers, Materials & Continua 2025年第2期82卷 3131-3159页

作者： Yuanjing Hao Xuemin Wang Liang chang long Li Mingmeng Zhang Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin541004China

Dynamic publishing of social network graphs offers insights into user behavior but brings privacy risks, notably re-identification attacks on evolving data snapshots. Existing methods based on -anonymity can mitigate these attacks but are cumbersome, neglect dynamic protection of community structure, and lack precise utility measures. To address these challenges, we present a dynamic social network graph anonymity scheme with community structure protection (DSNGA-CSP), which achieves the dynamic anonymization process by incorporating community detection. First, DSNGA-CSP categorizes communities of the original graph into three types at each timestamp, and only partitions community subgraphs for a specific category at each updated timestamp. Then, DSNGA-CSP achieves intra-community and inter-community anonymization separately to retain more of the community structure of the original graph at each timestamp. It anonymizes community subgraphs by the proposed novel -composition method and anonymizes inter-community edges by edge isomorphism. Finally, a novel information loss metric is introduced in DSNGA-CSP to precisely capture the utility of the anonymized graph through original information preservation and anonymous information changes. Extensive experiments conducted on five real-world datasets demonstrate that DSNGA-CSP consistently outperforms existing methods, providing a more effective balance between privacy and utility. Specifically, DSNGA-CSP shows an average utility improvement of approximately 30% compared to TAKG and CTKGA for three dynamic graph datasets, according to the proposed information loss metric IL.

关键词： Dynamic social network graph k-composition anonymity community structure protection graph publishing security and privacy

Bound state noise-like pulses generation from composite filtering effects

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Optoelectronics Letters 2025年第3期21卷 142-148页

作者： chang Qingyu ZHANG Caishi College of Physics & Optoelectronic Engineering Jinan University Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology School of Physics and Optoelectronic EngineeringMacau University of Science and Technology School of Innovation Engineering Macau University of Science and Technology

This paper demonstrated the generation of multi-wavelength bound state noise-like pulse (BNLP) in a dispersion-managed composite-filtered fiber laser consisting of nonlinear polarization rotation (NPR) and *** the case of BNLP,the generation is caused by the interaction between two noise-like pulses (NLPs) induced by the comb-filtering effect,and bound state level can be artificially controlled in the *** work provides a new method for generating low-coherence pulses and establishes a research idea for the study of the comb-filtering effects.

关键词： A