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Coupled Influence of Temperature and Strain Rate on Tensile Deformation Characteristics of Hot-Extruded AZ31 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 163-172页

作者： Ying Yan Wan-Peng Deng zhan.Feng Gao Jing Zhu Zhong-Jun Wang Xiao-Wu Li Institute of Materials Physics and Chemistry School of Materials Science and Engineering Northeastern University College of Materials and Metallurgy Liaoning University of Science and Technology Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University

To explore the coupled effect of temperature T and strain rate ε on the deformation features of AZ31 Mg alloy, mechanical behaviors and microstructural evolutions as well as surface deformation and damage features were system- atically examined under uniaxial tension at T spanning from 298 to 523 K and ε from 10^-4 to 10^-2 s-1. The increase in T or the decrease in ε leads to the marked decrease in flow stress, the appearance of a stress quasi-plateau after an initially rapid strain hardening, and even to the occurrence of successive strain softening. Correspondingly, the plastic deformation modes of AZ31 Mg alloy transform from the predominant twinning and a limited amount of dislocation slip into the enhanced non-basal slip and the dynamic recrystallization （DRX） together with the weakened twinning. Meanwhile, the cracking modes also change from along grain boundaries （GBs） and at twin boundaries （TBs） or the end of twins into nearby GBs where the DRX has occurred. The appearance of a stress quasi-plateau, the formation of large-sized cracks nearby GBs, and the occurrence of continuous strain softening, are intimately related to the enhancement of the non-basal slip and the DRX.

关键词： AZ31 Mg alloy Uniaxial tension Temperature Strain rate Deformation Damage Twinning

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基于PSO的飞行器姿态智能控制技术研究

计算机仿真 2024年第3期41卷 64-70,80页

作者：万春秋詹韬李擎韩旭东北京科技大学自动化学院北京100083 北京控制与电子技术研究所北京100038

以气动舵/推力矢量/直接力复合控制飞行器为对象,研究了多维异构复合姿态控制系统的控制律及分配律一体化智能设计问题。首先提出了基于PSO(Particle Swarm Optimization)算法的“智能控制律+智能分配律”飞行器姿态多维异构智能复合控... 详细信息

以气动舵/推力矢量/直接力复合控制飞行器为对象,研究了多维异构复合姿态控制系统的控制律及分配律一体化智能设计问题。首先提出了基于PSO(Particle Swarm Optimization)算法的“智能控制律+智能分配律”飞行器姿态多维异构智能复合控制算法框架,并建立了控制系统数学模型,然后重点研究了控制律及分配律参数的智能优化算法实现方法,最后通过数学仿真验证了提出方法的有效性。仿真结果表明,所设计智能优化复合控制系统在标称模型以及模型摄动情况下均能够实现对姿态角指令的准确快速跟踪。

关键词：飞行器姿态多维异构复合控制智能控制律+智能分配律粒子群算法

Preparation of Mo_2C nanoparticles dispersion-strengthened copper-based composite by EB-PVD

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Rare Metals 2014年第5期33卷 568-572页

作者： Xiao Li Guang-Ping Song Fan-Yu Bu Bin Xu Bai-Yang Lou zhan.Lin College of Materials Science and Engineering Zhejiang University of Technology Center for Composite Materials and Structures Harbin Institute of Technology

In this research, a nano-Mo2 C particle dispersion-strengthened copper alloy was prepared by a novel method, i.e., electron beam physical vapor deposition（EBPVD） which has advantages of simple technical process and low cost compared with the conventional mechanical alloying method. And the microstructure and properties of the material were investigated. The results show that the copper matrix is composed of columnar crystals with the average width of 7 lm, and the size of Mo2 C dispersoid is1–7 nm. The ultimate tensile strength of the material is486 MPa, and the electrical conductivity is 82 % IACS. As the temperature increases from 293 to 573 K, the material becomes more brittle.

关键词： Electron beam physical vapor deposition Dispersion-strengthened copper ODS In-situ

护士主导的医护技联合康复模式在前交叉韧带重建术病人中的应用

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骨科 2024年第5期15卷 450-455页

作者：刘洪娟詹雪王倩肖琦吴明珑华中科技大学同济医学院附属同济医院护理部武汉430030

目的探讨护士主导的医护技联合康复模式对前交叉韧带重建术(ACLR)后病人功能恢复和重返运动的影响。方法按照病人入院的先后顺序,将我院骨科2021年1月至6月收治的50例病人纳入对照组,进行常规治疗护理和康复指导;2021年7月至2022年1月... 详细信息

目的探讨护士主导的医护技联合康复模式对前交叉韧带重建术(ACLR)后病人功能恢复和重返运动的影响。方法按照病人入院的先后顺序,将我院骨科2021年1月至6月收治的50例病人纳入对照组,进行常规治疗护理和康复指导;2021年7月至2022年1月收治的50例病人纳入观察组,在常规治疗护理的基础上进行以护士主导的医护技联合康复。观察两组病人术后1~3 d、6个月和12个月数字评分法(NRS)的静、动态疼痛得分,术后首次下床活动时间,术后6个月和12个月国际膝关节文献委员会(IKDC)膝关节主观评分和Lysholm膝关节评分,以及术后重返运动和异常体征情况。结果干预后,观察组术后1~3 d的动、静态NRS疼痛得分和术后6个月的动态NRS疼痛得分显著低于对照组(P<0.05),术后首次下床活动时间早于对照组(P<0.05),术后6个月和12个月IKDC膝关节主观得分和Lysholm膝关节得分均显著高于对照组(P<0.05)。术后1年,观察组关节不稳的发生率明显低于对照组(8.51%vs.25.00%,P=0.032),重返运动率高于对照组(25.53%vs.12.50%,P=0.105)。结论护士主导的医护技联合康复模式可降低ACLR病人术后疼痛,促进病人早期下床活动,减少关节不稳的发生,提高膝关节功能的恢复,但在提高重返运动率方面还需要进一步的远程支持。

关键词：护士主导医护技联合康复前交叉韧带重建术

Objective Evaluation of Fabric Flatness Grade Based on Convolutional Neural Network

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Journal of Shanghai Jiaotong university(Science) 2021年第4期26卷 503-510页

作者： zhan.Zhu zhan. Wenjun CHEN Xia WANG Jun College of Textiles Donghua UniversityShanghai201620China Key Laboratory of Textile Science&Technology of Ministry of Education Donghua UniversityShanghai201620China

As an important indicator for the appearance and intrinsic quality of textiles, fabric flatness is the immediate cause affecting the aesthetic appearance and performance of textiles. In this paper, the objective evaluation system of fabric flatness based on 3D scanner and convolutional neural network (CNN) is constructed by using the height data of AATCC flatness template. The 3D scanner is responsible for the collection of the height value data of the sample. The effect of different sub-sample cutting sizes, cutting offsets, and network model depths on the objective evaluation coincidence rate of multiple flatness level was studied. The experimental results show that the coincidence rate of the system reaches 98.9% when the collected sample data are cut into subsamples of 20 pixel × 20 pixel with 12 pixel cutting offsets and the 11-layer network model is selected. Finally, this scheme is used to evaluate the flatness of four real fabrics with different colors and textures. The result shows that all of the samples can achieve a higher coincidence rate, which further verifies the adaptability and stability of the objective evaluation system constructed in this paper for fabric flatness evaluation.

关键词： fabric flatness convolutional neural network(CNN) computer vision image processing

Investigation of the effects of humic acid and H_(2)O_(2) on the photocatalytic degradation of atrazine assisted by microwave

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Frontiers of Environmental Science & Engineering 2010年第3期4卷 321-328页

作者： Chao QIN Shaogui YANG Cheng SUN Manjun zhan.Rongjun WANG huan.ing CAI Jia ZHOU State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210093China Nanjing Research Institude of Environmental Protection Nanjing 210013China Changzhou Environmental Monitoring Center Changzhou 210093China

A solution of atrazine in a TiO_(2)suspension,an endocrine disruptor in natural water,was tentatively treated by microwave-assisted photocatalytic *** effects of mannitol,oxygen,humic acid,and hydrogen dioxide on the photodegradation rate were *** results could be deduced as follows:the photocatalytic degradation of atrazine fits the pseudo-first-order kinetic well with k=0.0328 s–1,and·OH was identified as the dominant *** of atrazine was hindered in the presence of humic acid,and the retardation effect increased as the concentration of humic acid increased.H_(2)O_(2)displayed a significant negative influence on atrazine photocatalysis *** on intermediates identified with gas chromatography-mass spectrometry(GC-MS)and Liquid chromatography-mass spectrometry(LC-MS/MS)techniques,the main degradation routes of atrazine are proposed.

关键词： atrazine retardation effect photocatalysis TiO_(2)

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激光功率对铁基合金熔覆层组织及性能的影响

材料热处理学报 2024年第3期45卷 184-194页

作者：曹甫洋郝展良王浩权王资兴廖俊袁志钟罗锐江苏大学材料科学与工程学院江苏镇江212013 江苏集萃先进金属材料研究所江苏常熟215500 天工国际粉末冶金研究院江苏镇江212312

选取5种不同的激光功率(1000、1200、1400、1600和1800 W)在Q235碳素钢表面制备铁基合金熔覆层,利用光学显微镜(OM)、X射线衍射(XRD)、扫描电镜(SEM)、电子背散射衍射(EBSD)技术、显微维氏硬度计和往复摩擦磨损试验机等研究了熔覆层的... 详细信息

选取5种不同的激光功率(1000、1200、1400、1600和1800 W)在Q235碳素钢表面制备铁基合金熔覆层,利用光学显微镜(OM)、X射线衍射(XRD)、扫描电镜(SEM)、电子背散射衍射(EBSD)技术、显微维氏硬度计和往复摩擦磨损试验机等研究了熔覆层的组织、力学性能和摩擦磨损性能。结果表明:熔覆层组织由枝晶内马氏体、枝晶间铁素体与部分残留奥氏体构成。随着激光功率的增加,熔覆层的厚度与稀释率增加,二次枝晶界面逐渐大量溶解,残留奥氏体量不断降低。当激光功率为1200 W时,熔覆层的平均硬度最高,为606.4 HV0.5,是基材硬度的3.6倍,磨损体积与磨损率最小,表现出良好的耐磨性能。熔覆层磨损机制是磨粒磨损与黏着磨损。

关键词：激光熔覆铁基合金熔覆层硬度摩擦磨损

Interference properties of two-component matter wave solitons

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Chinese Physics B 2020年第2期29卷 112-120页

作者： Yan-Hong Qin Yong Wu Li-Chen Zhao zhan.Ying Yang School of Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China School of Public Management Northwest UniversityXi'an 710127China

Wave properties of solitons in a two-component Bose-Einstein condensate are investigated in *** demonstrate that dark solitons in one of components admit interference and tunneling behavior,in sharp contrast to the scalar dark solitons and vector dark *** analyses of interference properties show that spatial interference patterns are determined by the relative velocity of solitons,while temporal interference patterns depend on the velocities and widths of two solitons,differing from the interference properties of scalar bright ***,for an attractive interactions system,we show that interference effects between the two dark solitons can induce some short-time density humps(whose densities are higher than background density).Moreover,the maximum hump value is remarkably sensitive to the variation of the solitons'*** a repulsive interactions system,the temporal-spatial interference periods of dark-bright solitons have lower *** simulation results suggest that interference patterns for the dark-bright solitons are more robust against noises than bright-dark *** explicit interference properties can be used to measure the velocities and widths of *** is expected that these interference behaviors can be observed experimentally and can be used to design matter wave soliton interferometer in vector systems.

关键词： solitons interference behavior tunneling dynamics two-component Bose-Einstein condensates

黄淮南部地区小麦品种矮秆基因的组成及其对茎秆特性的影响

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麦类作物学报 2024年第8期44卷 985-995页

作者：刘晓宇禹海龙裴星旭梁秋芳岳超程西永许海霞詹克慧河南农业大学农学院河南郑州450000

为研究矮秆基因及其组合对小麦茎秆特性的影响,以黄淮南部地区490个小麦品种(系)为材料,采用分子标记检测了小麦矮秆基因Rht-B1b、Rht-D1b、Rht8、Rht9、Rht12和Rht24,并连续2年测定了小麦株高、重心高度、节间长度、直径、折断力等茎... 详细信息

为研究矮秆基因及其组合对小麦茎秆特性的影响,以黄淮南部地区490个小麦品种(系)为材料,采用分子标记检测了小麦矮秆基因Rht-B1b、Rht-D1b、Rht8、Rht9、Rht12和Rht24,并连续2年测定了小麦株高、重心高度、节间长度、直径、折断力等茎秆特性,分析了矮秆基因的组成及其对茎秆特性的影响。结果表明,在490份材料中,携带Rht-B1b、Rht-D1b、Rht8、Rht9、Rht12和Rht24的材料分布频率分别为7.25%、92.24%、39.18%、42.86%、72.65%和95.31%,共得到了40种基因组合,其中分布频率较高的组合有Rht-D1b+Rht9+Rht12+Rht24(20.2%)、Rht-D1b+Rht12+Rht24(19.8%)、Rht-D1b+Rht8+Rht12+Rht24(16.3%)、Rht-D1b+Rht8+Rht9+Rht12+Rht24(8.4%)、Rht-D1b+Rht24(7.3%)、Rht-D1b+Rht9+Rht24(6.5%)、Rht-D1b+Rht8+Rht24(4.7%)和Rht-D1b+Rht8+Rht9+Rht24(3.9%)。矮秆基因对降低小麦株高的效应大小依次是Rht-D1b、Rht9、Rht8、Rht12和Rht-B1b,且基因间存在累加效应,但Rht8与Rht9或Rht12结合不能起到明显的降秆作用。基因组合Rht-D1b+Rht9+Rht12+Rht24对降低茎秆重心高度和基部前3节间长度以及增强基部前3节间折断力的效应最大,基因组合Rht-D1b+Rht8+Rht9+Rht24对降低穗下节长度的效应最大,基因组合Rht-D1b+Rht8+Rht12+Rht24对增大茎秆基部前3节间直径的效应最大。矮秆基因可以有效降低小麦的株高和重心高度,缩短基部第2、3节间长度,提高基部前3节间直径和折断力,可作为小麦的抗倒伏育种的重要依据。

关键词：黄淮南部地区小麦矮秆基因茎秆特性