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Mg对Al-22Si-10Ni合金组织和热学性能的影响

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铸造 2024年第2期73卷 174-179页

作者：李鹏宇张瑜璐李乙庚隋明冉南邵骏杜军华南理工大学材料科学与工程学院广东广州510640

Al-22Si-10Ni合金具有较高的导热性和较低的热膨胀特性,但硬度偏低,对其进行Mg合金化,研究Mg对该合金凝固组织和热学性能的影响。研究显示,Mg的加入主要影响合金的末期凝固进程,合金凝固末期反应由Al-Si-Al3Ni三元共晶反应向Al-Si-Mg2S... 详细信息

Al-22Si-10Ni合金具有较高的导热性和较低的热膨胀特性,但硬度偏低,对其进行Mg合金化,研究Mg对该合金凝固组织和热学性能的影响。研究显示,Mg的加入主要影响合金的末期凝固进程,合金凝固末期反应由Al-Si-Al3Ni三元共晶反应向Al-Si-Mg2Si三元共晶反应转变;热处理促进Mg_(2)Si析出,少量Mg加入后Al-22Si-10Ni合金的热导率小幅上升,继续添加Mg后,热导率出现下降;Mg对合金热膨胀系数影响较小,可显著提升合金的硬度。Al-22Si-10Ni-0.5Mg合金表现出优异的综合性能,其室温热导率130.3 W/(m·K),25~100℃范围内平均热膨胀系数为13×10^(-6)/K,硬度达到HV144,性能较为接近喷射沉积制备的高含量Al-50Si合金,具有成为电子封装用材料的潜能。

关键词： Al-22Si-10Ni合金凝固特性热导率热膨胀系数硬度

Deep learning characterization of rock conditions based on tunnel boring machine data

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Underground Space 2023年第5期12卷 89-101页

作者： Xu li Min Yao Ji-dong yuan yu-jie Wang peng-yu li Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China China Institute of Water Resources and Hydropower Research Beijing 100048China China Railway Engineering Equipment Group Co. Ltd.Zhengzhou 450000China

Rock condition perception based on tunnel boring machine(TBM)data is of great importance for not only ensuring tunnel boring safety but also improving construction *** prediction of TBM boring responses(i.e.,torque and total thrust of the cutterhead)largely determines the reliability of rock condition *** this paper,a new architecture of a two-dimensional convolutional neural network(2D-CNN)with a dual-input strategy is proposed to predict the TBM *** TBM Lot 3 of the Yinsong project in Jilin province,China,is taken as the case study in this *** types of models that follow different learning strategies are compared:one is defined as the point model,which only learns data of the stable phase,and the other is defined as the line model,which learns data from both the loading and stable boring *** line model is further improved by the weighted loss function *** results indicate that the strategy of learning data from both the loading phase and stable boring phase and increasing the weight of samples from the stable phase is shown to be optimal in predicting TBM boring *** terms of learning strategies,the line model can learn the influence of active control parameters on passive response parameters,but the point model *** terms of machine learning algorithms,2D-CNN has the best performance,with R2 values of 0.865 and 0.923 for torque and total thrust,*** proposed line model can overcome the problem that the traditional model failed to learn the influence of control *** a model can provide a solid base for the timely optimization of the control parameters in TBM boring process.

关键词： TBM Rock condition perception 2D-CNN Weighted loss function line model

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硫酸法烷基化装置存在的腐蚀问题与解决措施

全面腐蚀控制 2024年第1期38卷 119-124页

作者：尚智李朋宇杨富淋大连西太平洋石油化工有限公司辽宁大连116600 沈阳中科韦尔腐蚀控制技术有限公司辽宁沈阳110000

大连某石化公司硫酸法烷基化装置自2013年重新投产运行以来,多个系统及部位发生过硫酸腐蚀泄漏,严重影响装置的安全平稳生产。根据各部位腐蚀情况,研究各腐蚀形成的机理,分析出现腐蚀的原因,制定有针对性的解决方案及措施,通过材质升级... 详细信息

大连某石化公司硫酸法烷基化装置自2013年重新投产运行以来,多个系统及部位发生过硫酸腐蚀泄漏,严重影响装置的安全平稳生产。根据各部位腐蚀情况,研究各腐蚀形成的机理,分析出现腐蚀的原因,制定有针对性的解决方案及措施,通过材质升级、保护优化、设备设施升级改造等手段,减少了装置腐蚀情况的发生。

关键词：硫酸法烷基化硫酸腐蚀材料解决措施

Fourth-order phase-field modeling for brittle fracture in piezoelectric materials

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 837-856页

作者： yu TAN Fan peng Chang liU Daiming peng Xiangyu li State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Science Chang'an UniversityXi'an 710064China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Failure analyses of piezoelectric structures and devices are of engineering and scientific *** this paper,a fourth-order phase-field fracture model for piezoelectric solids is developed based on the Hamilton *** typical electric boundary conditions are involved in the present model to characterize the fracture behaviors in various physical situations.A staggered algorithm is used to simulate the crack *** polynomial splines over hierarchical T-meshes(PHT-splines)are adopted as the basis function,which owns the *** numerical simulations are performed to study the influence of the electric boundary conditions and the applied electric field on the fracture behaviors of piezoelectric *** electric boundary conditions may influence crack paths and fracture loads *** present research may be helpful for the reliability evaluation of the piezoelectric structure in the future applications.

关键词： isogeometric analysis(IGA) brittle fracture fourth-order phase-field model piezoelectric solid

Polydopamine modified CuS@HKUST for rapid sterilization through enhanced photothermal property and photocatalytic ability

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Rare Metals 2022年第2期41卷 663-672页

作者： Dong-lin Han peng-li yu Xiang-Mei liu Ying-De Xu Shui-lin Wu College of Materials Science and Engineering Jilin Institute of Chemical TechnologyJilin 132022China School of Materials Science and Engineering the Key Laboratory of Advanced Ceramics and Machining Technology by the Ministry of Education of ChinaTianjin UniversityTianjin 300072China Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China

Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great ***,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisitely designed,where the Cu-based metal-organic framework(MOF)—HKUST nanoparticles served as the porous frame,and the CuS was synthesized within the structure of the MOF through the process of in situ sulfuration,followed with polydopamine(PDA)covering the *** structure of the HKUST preventing the aggregation of the CuS nanoparticles,which improved their photothermal and photocatalytic *** covering with PDA,the nanoparticles’abilities to produce heat and free radicals were further *** was because that the PDA itself could transform light into heat,which not only benefited the photothermal property,but also improved the photocatalytic property of the nanoparticles by accelerating the charge ***,the PDA could also transfer the photo-induced electrons fast and thus prevented the recombination of the photo-generated electron–hole pairs,which resulted in the enhanced ability to produce free *** a result,under light irradiation,the antibacterial efficiency of the CuS@HKUST-PDA against Staphylococcus aureus(***)and Escherichia coli(***)could reach 99.77%and 99.57%.Hence,the synthesized CuS@HKUST-PDA can be promising for anti-infection and sterilization application without using antibiotics.

关键词： Antibacterial CuS Polydopamine(PDA) Photothermal Photocatalytic Metal-organic framework(MOF)

Machine Learning-based Identification of Contaminated Images in light Curve Data Preprocessing

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Research in Astronomy and Astrophysics 2024年第4期24卷 287-295页

作者： Hui li Rong-Wang li peng Shu yu-Qiang li yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Space Object and Debris Observation Chinese Academy of SciencesNanjing 210023China

Attitude is one of the crucial parameters for space objects and plays a vital role in collision prediction and debris *** light curves to determine attitude is the most commonly used *** photometric observations,outliers may exist in the obtained light curves due to various ***,preprocessing is required to remove these outliers to obtain high quality light *** statistical analysis,the reasons leading to outliers can be categorized into two main types:first,the brightness of the object significantly increases due to the passage of a star nearby,referred to as“stellar contamination,”and second,the brightness markedly decreases due to cloudy cover,referred to as“cloudy contamination.”The traditional approach of manually inspecting images for contamination is time-consuming and ***,we propose the utilization of machine learning methods as a *** Neural Networks and SVMs are employed to identify cases of stellar contamination and cloudy contamination,achieving F1 scores of 1.00 and 0.98 on a test set,*** also explore other machine learning methods such as ResNet-18 and light Gradient Boosting Machine,then conduct comparative analyses of the results.

关键词： techniques:image processing methods:data analysis light pollution

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全断面硬岩隧道掘进机岩体状态智能识别技术

建筑机械 2024年第8期 108-111页

作者：裴成元李鹏宇杨晨张娜新疆水发建设集团有限公司新疆乌鲁木齐830000 中铁工程装备集团有限公司河南郑州450016

全断面硬岩隧道掘进机在隧道施工领域应用广泛,如何快速对掌子面在掘岩体进行感知和识别成为行业研究热点。文章尝试2种方法开展研究:通过收集地质和施工大数据,建立岩机模型实时获取在掘岩体力学信息;基于机器视觉技术,对渣土进行图像... 详细信息

全断面硬岩隧道掘进机在隧道施工领域应用广泛,如何快速对掌子面在掘岩体进行感知和识别成为行业研究热点。文章尝试2种方法开展研究:通过收集地质和施工大数据,建立岩机模型实时获取在掘岩体力学信息;基于机器视觉技术,对渣土进行图像分析,构建围岩等级模型。对2种方法进行了总结,并对下一步研究方向进行了讨论。

关键词：岩体识别岩机模型渣片识别

Room-temperature ferroelectricity in van der Waals SnP_(2)S_(6)

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Frontiers of physics 2024年第4期19卷 113-123页

作者： Chaowei He Jiantian Zhang li Gong peng yu State Key Laboratory of Optoelectronic Materials and Technologies Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices Nanotechnology Research Center School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Instrumental Analysis and Research Center Sun Yat-sen UniversityGuangzhou 510275China

Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power *** the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant ***,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) *** polarization is observed in thin SnP_(2)S_(6) of~7 ***,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic *** addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) *** results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.

关键词： two-dimensional ferroelectric materials ferroelectric fieldeffect transistors photodetectors

Research on the mechanism of the two-dimensional ultrasonic surface burnishing process to enhance the wear resistance for aluminum alloy

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Friction 2024年第3期12卷 490-509页

作者： Zhen-yu ZHOU Qiu-Yang ZHENG yu li Cong DING Guang-Jian peng Zhong-yu PIAO College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China

The gradient nanostructure is machined on the aluminum(Al)alloy by the two-dimensional ultrasonic surface burnishing process(2D-USBP).The mechanism of why the gradient nanostructure enhances wear resistance is *** mechanical properties and microstructure characterization for the gradient nanostructure are performed by operating a nanoindenter,transmission electron microscopy(TEM),and electron backscattered diffraction(EBSD).Dry wear tests are performed on the samples before and after machining to evaluate the wear resistance and *** effect of the gradient nanostructure on the wear resistance is explored by developing the crystal plasticity(CP)finite element and molecular dynamics(MD)*** characterization results show that the 2D-USBP sample prepared a gradient structure of~600μm thick on the aluminum surface,increasing the surface hardness from 1.13 to 1.71 GPa and reducing the elastic modulus from 78.84 to 70.14 *** optimization of the surface microstructure and the increase of the mechanical properties effectively enhance the wear resistance of the sample,with 41.20%,39.07%,and 54.58% of the wear scar areas for the 2D-USBP treated samples to the original samples under 5,10,and 15 N loads,*** gradient nanostructure hinders the slip of dislocations inside the sample during the wear process and reduces the size and scope of plastic deformation;meanwhile,the resistance to deformation,adhesion,and crack initiation and propagation of the sample surface is improved,resulting in enhanced wear resistance.

关键词： structural superlubricity lattice registry elastic deformation strained solitons crystal plasticity molecular dynamics simulations