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Journal of Advanced Ceramics 2024年第5期13卷 689-698页

作者： Qingyi Kong Lei Chen Sijia Huo Kunxuan Li Wenyu Lu yujin wang Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Key Laboratory of Advanced Structure‒Function Integrated Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

To address the relatively mediocre mechanical properties of single-phase multi-component carbide ceramics,a phase transition from a single phase to multiple phases was proposed to achieve superior mechanical properties.A series of(TiZrV_(x)Nb)C_(0.8) ceramics with different V contents were fabricated by spark plasma sintering(SPS).The influence of the V content on the phase composition,microstructural evolution,and mechanical properties was investigated in *** transition behavior from a single phase to multiple phases is discovered and *** formation of the Zr-rich phase and Zr-poor phase can be attributed to the increase in lattice distortion and mixed enthalpy caused by the addition of V.A nanometer lamellar structure with a semi-coherent interface obtained via in situ decomposition is reported for the first time in multi-component carbide *** semi-coherent interfaces with high dislocation density and strain concentration effectively improve the mechanical properties,grain refinement,and multi-phase *** optimal comprehensive mechanical properties of the Vickers hardness(26.3 GPa),flexural strength(369 MPa),and fracture toughness(3.1 MPa·m^(1/2))were achieved for the sample with 20 mol%V.

关键词： multi-component ceramics multiple phases microstructure evolution phase decomposition mechanical properties

Phase transition of multi-component(TiZrVNb)C ceramics—Part I:Phase decomposition induced by carbon content

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Journal of Advanced Ceramics 2024年第5期13卷 679-688页

作者： Qingyi Kong Rao Zhang Lei Chen Sijia Huo Wenyu Lu yujin wang Boxin Wei Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Key Laboratory of Advanced Structure‒Function Integrated Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150001China National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

Phase decomposition can effectively enhance the mechanical properties of carbide ceramics and can overcome the difficulty of enhancing the mechanical properties of single-phase multicomponent carbide *** this work,a series of nonstoichiometric(TiZrVNb)Cx ceramics were prepared by spark plasma sintering(SPS)at different *** effects of the carbon content on the phase composition,microstructure evolution,and mechanical properties were investigated in *** decomposition occurred with decreasing carbon *** different solid solutions of(Ti,V)-rich and Zr-rich phases formed from the decomposition of equimolar single-phase solid solutions,namely,the Zr-poor phase and Zr-rich phase,*** distribution of Nb element is relatively *** semicoherent interfaces between the Zr-poor phase and the Zr-rich phase can harden and strengthen effectively under the synergistic effect of grain *** with phase decomposition structures have apparent advantages compared to single-phase high-entropy *** work provides an important train of thought for the microstructure tailoring and properties optimization of multi-component carbide ceramics.

关键词： multicomponent ceramics nontoichiometry microstructure evolution phase decomposition mechanical properties

鲁迅与章太炎传奇小说观之差异及其流衍——重审20世纪以来唐传奇文体的升格

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鲁迅研究月刊 2024年第4期 29-38页

作者：王瑜锦南通大学文学院 226019

清末章太炎提出“唐人始造意为巫蛊媟渎之言”,唐传奇背弃了汉代小说开创的街谈巷议、有益于政教的传统,当被视为变体,持类似观点的还有吴虞、朱希祖、浦江清等人。然而在西化小说观和文学观的冲击下,古典小说在20世纪以来逐渐失去了传... 详细信息

清末章太炎提出“唐人始造意为巫蛊媟渎之言”,唐传奇背弃了汉代小说开创的街谈巷议、有益于政教的传统,当被视为变体,持类似观点的还有吴虞、朱希祖、浦江清等人。然而在西化小说观和文学观的冲击下,古典小说在20世纪以来逐渐失去了传统底色,重“情”、尚“美”、提倡虚构等“现代因子”逐步成为小说的内在要义。在这一背景下,传奇小说的地位被不断抬升,鲁迅所提出的唐人“始有意为小说”的观点广泛传播并占据主流,章太炎等人的观点则逐渐隐没,成为边缘。

关键词：传奇小说观念章太炎鲁迅朱希祖浦江清

基于扰动观测器和鲁棒模型预测的电动汽车集群调频方法研究

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电源学报 2024年第05期22卷 220-229页

作者：王晖南王昱瑾国网山西省电力公司营销服务中心

提出1种适用于高渗透率可再生能源孤岛型电网中大量电动汽车EVs(electric vehicles)的频率调节方法。首先，针对系统的降阶模型设计了扰动观测器，为聚集的电动汽车产生附加频率控制信号。该降阶模型通过结合负荷、风电、光伏系统和聚... 详细信息

提出1种适用于高渗透率可再生能源孤岛型电网中大量电动汽车EVs(electric vehicles)的频率调节方法。首先，针对系统的降阶模型设计了扰动观测器，为聚集的电动汽车产生附加频率控制信号。该降阶模型通过结合负荷、风电、光伏系统和聚集电动汽车的变化而获得，可以产生1个由扰动观测器估计的集总扰动；然后，提出1种基于Tube模型的鲁棒预测控制RMPC(robust model predictive control)方法，以提供有效的控制信号，提高聚合后电动汽车的响应能力。控制信号的产生是为了以最小的控制动作获得频率偏差误差的最小值，同时考虑各种系统运行物理约束；接着，通过稳定性分析研究了时延对通信链路的影响，获得了时延裕度；最后，通过仿真分析验证了所提方法的有效性，并验证了所提方法相对于传统MPC、模糊比例积分控制和线性二次调节器控制的优越性。

关键词：扰动观测器电动汽车负载频率控制鲁棒控制

基于改进U-Net的皮革表面缺陷精细化分割方法

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计算机辅助设计与图形学学报 2024年第3期36卷 413-422页

作者：王愉锦黄惠玲付磊韩军福州大学先进制造学院泉州362000 中国科学院福建物质结构研究所泉州装备制造研究中心泉州362000

针对皮革缺陷形态多变、局部相似程度高导致细节信息难以提取、类型错分的问题,提出一种基于改进U-Net结构的表面缺陷精细化分割方法.编码端,在保留原始图像细节特征的同时嵌入级联扩张卷积模块获取全局特征,同时在跳跃连接中添加特征... 详细信息

针对皮革缺陷形态多变、局部相似程度高导致细节信息难以提取、类型错分的问题,提出一种基于改进U-Net结构的表面缺陷精细化分割方法.编码端,在保留原始图像细节特征的同时嵌入级联扩张卷积模块获取全局特征,同时在跳跃连接中添加特征融合模块,改善因高低特征张量直接拼接造成的局部信息丢失;解码端使用基于通道注意力机制的解码模块代替原始卷积层,自适应地指导网络关注缺陷区域;为进一步整合高层信息,还嵌入全局平均池化模块,将输出结果作为解码端的语义指导增强网络对相似缺陷的分辨能力.在包含7种缺陷的皮革数据集上进行实验的结果表明,所提方法在PA,MPA,FWIoU和MIoU上分别达到99.17%,93.27%,98.39%和88.88%,对比U-Net分别提升0.28,2.78,0.53和4.03个百分点;定性分析和定量分析结果表明,该方法对于皮革缺陷能得到更加精细的分割结果.

关键词：皮革缺陷语义分割 U-Net 特征融合注意力机制扩张卷积

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蜂窝结构海上风力机防护装置性能研究

振动与冲击 2024年第10期43卷 215-222页

作者：刘坤鹏缪维跑王瑀琎李春岳新智上海理工大学能源与动力工程学院上海200093

为便于风力机运输、安装及维护,海上风电场大多处于繁忙的航道,导致海上风力机受船舶碰撞概率大幅上升。为增强海上风力机抗撞能力,减轻碰撞区域受损程度,提高其抗风险性能,提出一种具有蜂窝结构特征的新型防护装置。采用显示动力分析软... 详细信息

为便于风力机运输、安装及维护,海上风电场大多处于繁忙的航道,导致海上风力机受船舶碰撞概率大幅上升。为增强海上风力机抗撞能力,减轻碰撞区域受损程度,提高其抗风险性能,提出一种具有蜂窝结构特征的新型防护装置。采用显示动力分析软件LS-DYNA模拟5 000 t级船舶与4 MW海上风力机单立柱三桩基础碰撞过程,研究蜂窝结构新型防护装置与传统实心结构防护装置抗撞性能的差别。结果表明:具有蜂窝结构特征的新型防护装置可有效延长接触时间,降低接触力;较传统实心防护装置,新型装置内能转化能力提升15%以上,蜂窝结构起到提升内能转化能力的作用。蜂窝结构防护装置具备良好的吸能缓冲效果,可有效削减传递至风力机结构的内能及动能,降低基础损伤,起到提升单立柱三桩基础海上风力机安全性的功能。

关键词：海上风力机蜂窝结构碰撞抗撞性

Microstructure and Mechanical Properties of ZrC_(x)-NbC_(y)-Cu Composites by Reactive Infiltration at 1300℃

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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 52-58页

作者：王东 XU Kai WEI Boxin wang yujin Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials(Anhui University of Technology) Ministry of EducationMa’anshan 243002China School of Materials Science and Engineering Anhui University of TechnologyMa’anshan 243002China Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150080China

ZrC_(x)-NbC_(y)-Cu composites were fabricated by pressure-less reactive infiltration of Zr-Cu binary melts into porous NbC preforms at 1300℃.The effect of Zr content in the infiltrator on microstructure of the as-synthesized composites was *** properties of the composites were reported.A partial displacement of Nb atoms in NbC by Zr atoms from Zr-Cu melt occurs during the reaction between Zr-Cu melt and porous NbC *** formation of a core-shell structure suggests the reaction is mainly a dissolutionprecipitation *** dissolves into Zr-Cu melt,from which the(Nb,Zr)C_(z)phase precipitates and *** increasing Zr content in the Zr-Cu infiltrator,the reaction is enhanced and the infiltration is easily ***_(x)-NbC_(y)-Cu composite is synthesized using Zr_(14)Cu_(51)*** flexural strength and fracture toughness of ZrC_(x)-NbC_(y)-Cu composite reach 637 MPa and 12.7 MPa·m^(1/2),*** the improved toughness is probably attributed to residual Cu phase and plate-like Nb_(x)C_(y)phases.

关键词： ZrC_(x)-NbC_(y)-Cu composite reactive melt infiltration microstructure mechanical properties

Elevated Temperature Strength of TiC_(p)/W Composites

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Journal of Materials Science & Technology 2001年第1期17卷 31-32页

作者： yujin wang Yu ZHOU Guiming SONG Tingquan LEI School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The elevated temperature mechanical properties of TiCp,/W composites produced using powder metallurgical technique were investigated. Results show that with increasing temperature, the strength of TiCp/W composites increases gradually and reaches its maximum value at 1000℃, which is much higher than that at room temperature. The strengthening mechanisms at high temperature are attributed to dislocation strengthening and load transfer between matrix and particles.

关键词： dislocation strengthening mechanical properties elevated temperature room temperature high temperature maximum value load transfer strength of

Synthesis of Ag@Cu_2O core-shell metal-semiconductor nanoparticles and conversion to Ag@Cu core-shell bimetallic nanoparticles

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Science China(Technological Sciences) 2015年第5期58卷 881-888页

作者： YANG AiLing LI ShunPin wang yujin wang LeLe BAO XiChang YANG RenQiang Department of Physics Ocean University of China Qingdao Institute of Bioenergy & Bioprocess Technology Chinese Academy of Sciences

Ag@Cu2O core-shell metal-semiconductor nanoparticles(NPs) were prepared by using solution phase strategy. It was found that Ag@Cu2O core-shell NPs were easily converted to Ag@Cu bimetallic core-shell NPs with the help of surfactant PVP and excessive reducer ascorbic acid in air at room temperature, which is a unique phenomenon. Varying volumes of Ag colloidal solutions were added into the reaction mixtures containing fixed initial concentrations of Cu2+ and PVP, Ag@Cu2O and Ag@Cu core-shell NPs with fixed core size but varying outer shell thicknesses could be obtained. The composites, structures, morphologies and extinction properties of Ag@Cu2O and Ag@Cu core-shell NPs were systematically characterized by XRD, TEM and extinction spectra. Both of these NPs show wide tunable optical properties. The extinction peaks could be shifted from 421 nm to 700 nm. FTIR results reveal that Cu+ ions on the surface of Cu2 O nanocrystalline coordinate with N and O atoms in PVP and further are reduced to metallic Cu by excessive ascorbic acid and then form a nucleation site on the surface of Cu2 O nanocrystalline. PVP binds onto a different site to proceed with the reduction until all the Cu sources in Cu2 O NPs are completely assumed. And the shell of Cu2 O is converted to Cu shell. The synthesis approach in this paper is simple and also a promising reference for synthesizing other core-shell NPs. Ag@Cu2O NPs can be easily converted to Ag@Cu NPs in air at room temperature, which is promising to be used in electronic devices.

关键词： surfactant systematically nucleation silver synthesizing metallic colloidal reactant extinction ascorbic

Dislocation Behavior in ZrC Particles during Elevated Temperature Compressive Deformation of a 30 vol.% ZrC_p/W Composite

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Journal of Materials Science & Technology 2011年第6期27卷 553-558页

作者： Taiquan Zhang Qingchang Meng yujin wang Yu Zhou Guiming Song Institute for Advanced Ceramics Harbin Institute of Technology Harbin 150001 China China National R&D Center for lhngsten Technology Xiamen 361009 China Department of Materials Science and Engineering Delft University of Technology Mekelweg 2 2628CD Delft the Netherlands

A 30 vol.% ZrCp/W composite has been deformed in compression in the temperature range of 1200-1600℃.Dislocation nucleation mechanism in ZrC particles is discussed by analyzing the harmonious deformation between tungsten-matrix and ZrC *** activation apparently increases the mobility of screw segments,resulting in the formation of many kinetics jogs and thermodynamics jogs above 1300℃.The formation mechanisms of the dislocation configurations are studied.

关键词： ZrCp/W composite ZrC particle Compressive deformation Dislocation microstructure