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Journal of Magnesium and Alloys 2024年第3期12卷 1186-1203页

作者： biaobiao yang Javier LLorca IMDEA Materials Institute C/Eric Kandel 2GetafeMadrid 28906Spain Department of Materials Science Polytechnic University of Madrid/Universidad Politécnica de MadridE.T.S.de Ingenieros de CaminosMadrid 28040Spain

A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction.The deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice rotation.It was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple junctions.They were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice rotations.Moreover,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain incompatibility.These results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations.

关键词： Magnesium Extension twinning In-situ electron back-scattered diffraction basal slip Deformation mechanisms.

Effect of Ti additions on microstructure and mechanical properties of Cu-Cr-Zr alloy

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Journal of Materials Science & Technology 2023年第32期163卷 69-80页

作者： Chenying Shi Muzhi Ma biaobiao yang Yuling Liu Yushen Huang Yong Du State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China IMDEA Materials Institute C/Eric Kandel 2Getafe28906 MadridSpain Department of Materials Science Polytechnic University of Madrid/Universidad Politécnica de MadridE.T.S.de Ingenieros de Caminos28040 MadridSpain

Ti additions in Cu–Cr–Zr alloys are useful for achieving high mechanical properties.In this work,the influence of Ti contents(0.25 wt%,0.6 wt%,and 1.02 wt%)on the microstructure,mechanical,and electrical properties of Cu–Cr–Zr alloys has been investigated experimentally,along with thermodynamic and kinetic calculations.The electrical conductivity decreased but the hardness/strength increased with increasing Ti content.The lower electrical conductivity is due to increased electron scattering through the solution of more Ti atoms in the Cu matrix.As for the higher hardness/strength,it is mainly owing to higher dislocation density and finer FCC-Cr precipitates.Furthermore,a model considering the size distributions of precipitates is adopted to calculate precipitation strengthening quantitatively.The calculated yield strengths are consistent with the experimental ones for the alloys.The thermodynamic and kinetic calculations reveal that increasing Ti content can facilitate the nucleation of FCC-Cr but enhance its activation energy,hence hindering the growth process.The present work study can provide an effective strategy for producing copper alloys with expected performance.

关键词： Cu-Cr-Zr-Ti alloy Mechanical and electrical properties Microstructure Precipitation behavior Thermodynamic and kinetic calculations

Quasi-in-situ study on{10-12}twinning-detwinning behavior of rolled Mg-Li alloy in two-step compression(RD)-compression(ND)process

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Journal of Magnesium and Alloys 2022年第10期10卷 2775-2787页

作者： biaobiao yang Chenying Shi Siyu Zhang Jingjing Hu Jianwei Teng Yujie Cui Yunping Li Akihiko Chiba State Key Lab for Powder Metallurgy Central South UniversityChangsha 410083China Institute for Materials Research Tohoku UniversitySendai 980-8577Japan

Twinning-detwinning(TDT)behavior in a strongly basal-textured Mg-Li alloy during two-step compression(RD)-compression(ND)process was investigated using quasi-in-situ EBSD.TDT behavior and TDT variants selection were statistically discussed with the loading path for the first time.Non-Schmid twinning behavior was observed in the first step compression,owing to the local stress fluctuations by neighboring twins;in contrast,Schmid’s law well predicted the detwinning variants selection.This asymmetrical TDT behavior was first investigated to date related with the strong basal texture and loading path.Besides,with the progress of compression,Schmid factors for twinning demonstrated a decreasing tendency;however,those for detwinning during the second step displayed an abnormally increasing trend,fundamentally stemming from prior twinning behavior.

关键词： Twinning-detwinning Mg-Li alloy Quasi-in-situ Biaxial loading

Underlying slip/twinning activities of Mg-xGd alloys investigated by modified lattice rotation analysis

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Journal of Magnesium and Alloys 2023年第3期11卷 998-1015页

作者： biaobiao yang Chenying Shi Xianjue Ye Jianwei Teng Ruilin Lai Yujie Cui Dikai Guan Hongwei Cui Yunping Li Akihiko Chiba State Key Lab for Powder Metallurgy Central South UniversityChangsha 410083China Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Department of Materials Science and Engineering University of SheffieldMappin StreetSheffield S13JDUnited Kingdom School of Materials Science and Engineering Shandong University of TechnologyZibo 255000China

The inconsistencies regarding the fundamental correlation between Gd content and slip(twinning)activities of Mg alloys appeal further investigations.However,the traditional slip dislocations analysis by TEM is time-consuming,and that by SEM/EBSD cannot recognize the partial slip modes.These urge a more efficient and comprehensive approach to easily distinguish all potential slip modes occurred concurrently in alloy matrix.Here we report a modified lattice rotation analysis that can distinguish all slip systems and provide statistical results for slip activities in Mg alloy matrix.Using this method,the high ductility of Mg-Gd alloy ascribed to the enhanced non-basal slips,cross-slip,and postponed twinning activities by Gd addition is quantitatively clarified.

关键词： Mg-Gd alloy Non-basal slips Postponed twinning Grain boundary segregation Modified lattice rotation analysis

Inherent-attribute-aware dual-graph autoencoder for rating prediction

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Journal of Information and Intelligence

Journal of Information and Intelligence 2024年第1期2卷 82-97页

作者： yangtao Zhou Qingshan Li Hua Chu Jianan Li Lejia yang biaobiao Wei Luqiao Wang Wanqiang yang School of Computer Science and Technology Xidian UniversityXi'an 710071China Intelligent Financial Software Engineering New Technology Joint Laboratory Xidian UniversityXi'an 710071China Shanghai Fairyland Software Corp. Ltd.Shanghai 200233China

Autoencoder-based rating prediction methods with external attributes have received wide attention due to their ability to accurately capture users'preferences.However,existing methods still have two significant limitations:i)External attributes are often unavailable in the real world due to privacy issues,leading to low quality of representations;and ii)existing methods lack considering complex associations in users'rating behaviors during the encoding process.To meet these challenges,this paper innovatively proposes an inherent-attribute-aware dual-graph autoencoder,named IADGAE,for rating prediction.To address the low quality of representations due to the unavailability of external attributes,we propose an inherent attribute perception module that mines inductive user active patterns and item popularity patterns from users'rating behaviors to strengthen user and item representations.To exploit the complex associations hidden in users’rating behaviors,we design an encoder on the item-item co-occurrence graph to capture the co-occurrence frequency features among items.Moreover,we propose a dual-graph feature encoder framework to simultaneously encode and fuse the high-order representations learned from the user-item rating graph and item-item co-occurrence graph.Extensive experiments on three real datasets demonstrate that IADGAE is effective and outperforms existing rating prediction methods,which achieves a significant improvement of 4.51%~41.63%in the RMSE metric.

关键词： Rating prediction Graph convolutional network Autoencoder Inherent attribute aware

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管道机器人过T型管垂直爬坡动态性能分析

中国工程机械学报 2024年第2期22卷 179-184页

作者：汪洋焦彪彪陆青松杨晋安徽城市管理职业学院轨道交通学院安徽合肥230001 天津大学机械工程学院天津300350 山西北方机械制造有限责任公司山西太原030012

为进一步了解复杂管道的内部环境,设计一种全驱动轮式管道机器人。通过坐标旋转法,分析管道机器人通过T型管垂直爬坡时的姿态调整过程与运动状态变化,运用ADAMS动力学分析软件,分析管道机器人通过T型管时各驱动轮的受力情况和驱动轮质... 详细信息

为进一步了解复杂管道的内部环境,设计一种全驱动轮式管道机器人。通过坐标旋转法,分析管道机器人通过T型管垂直爬坡时的姿态调整过程与运动状态变化,运用ADAMS动力学分析软件,分析管道机器人通过T型管时各驱动轮的受力情况和驱动轮质心运动速度变化。研究发现管道机器人通过T型管时,其各驱动轮先后经历悬空状态并失去管壁支撑,4个驱动轮与管壁的接触力总的变化趋势均是先减小到0 N,然后随着驱动轮与管壁发生接触碰撞,接触力迅速增大,幅值超过其稳态值;前后2个驱动模块的驱动轮质心运动速度不同,前驱动模块驱动轮质心运动速度变化规律为类似正弦变化,后驱动模块由于接触碰撞,上部驱动轮与管壁发生打滑,驱动轮运动速度先轻微增大后迅速减小。研究结果为管道机器人的结构设计提供参考。

关键词：管道机器人 T型管姿态调整接触力运动速度

Microstructural evolution and defect formation in a powder metallurgy nickel-based superalloy processed by selective laser melting

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Journal of Materials Science & Technology 2020年第1期36卷 7-17页

作者： Hongyu Wu Dong Zhang biaobiao yang Chao Chen Yunping Li Kechao Zhou Liang Jiang Ruiping Liu State Key Laboratory for Powder Metallurgy Powder Metallurgy Research InstituteCentral South UniversityChangsha 410083China State Key Laboratory of Nickel and Cobalt Resources Comprehensive Utilization Jinchang 737100China Yuanmeng Precision Technology(Shenzhen)Institute Shenzhen 518063China

In this study,the selective laser melting(SLM)technology has been employed to manufacture a nickelbased superalloy which was conventionally prepared through powder metallurgy(PM)route.The microstructural features and defects were systematically investigated both prior to and after heat treatment and compared with the PM counterpart.Both solidification cracking and liquation cracking were observed in the SLM specimen in which the grain misorientation and low melting point(γ+γ')eutectic played a vital role in their formation mechanism.Columnar grains oriented along building direction were ubiquitous,corresponding to strongfiber texture.Solidification cell structures and melt pools are pervasive and noγ'precipitates were detected at about 10 nm scale before heat treatment.After supersolvus solution and two-step aging treatments,high volume fractionγ'precipitates emerged and their sizes and morphologies were comparable to those in PM alloy.texture is relieved and columnar grains tend to become more equiaxed due to static recrystallization process and grain boundary migration events.Significant annealing twins formed in SLM alloy and are clarified as a consequence of recrystallization.Our results provide fundamental understandings for the SLM PM nickel-based superalloy both before and after heat treatment and demonstrate the potential to fabricate this group of alloys using SLM technology.

关键词： Nickel-based superalloy Selective laser melting Microstructure Defects Annealing twin

基于FE-P2Pnet的无人机小麦图像麦穗计数方法

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农业机械学报 2024年第4期55卷 155-164,289页

作者：鲍文霞苏彪彪胡根生黄承沛梁栋安徽大学农业生态大数据分析与应用技术国家地方联合工程研究中心合肥230601

针对无人机图像背景复杂、小麦密集、麦穗目标较小以及麦穗尺寸不一等问题,提出了一种基于FE-P2Pnet(Feature enhance-point to point)的无人机小麦图像麦穗自动计数方法。对无人机图像进行亮度和对比度增强,增大麦穗目标与背景之间的... 详细信息

针对无人机图像背景复杂、小麦密集、麦穗目标较小以及麦穗尺寸不一等问题,提出了一种基于FE-P2Pnet(Feature enhance-point to point)的无人机小麦图像麦穗自动计数方法。对无人机图像进行亮度和对比度增强,增大麦穗目标与背景之间的差异度,减少叶、秆等复杂背景因素的影响。引入了基于点标注的网络P2Pnet作为基线网络,以解决麦穗密集的问题。同时,针对麦穗目标小引起的特征信息较少的问题,在P2Pnet的主干网络VGG16中添加了Triplet模块,将C(通道)、H(高度)和W(宽度)3个维度的信息交互,使得主干网络可以提取更多与目标相关的特征信息;针对麦穗尺寸不一的问题,在FPN(Feature pyramid networks)上增加了FEM(Feature enhancement module)和SE(Squeeze excitation)模块,使得该模块能够更好地处理特征信息和融合多尺度信息;为了更好地对目标进行分类,使用Focal Loss损失函数代替交叉熵损失函数,该损失函数可以对背景和目标的特征信息进行不同的权重加权,进一步突出特征。实验结果表明,在本文所构建的无人机小麦图像数据集(Wheat-ZWF)上,麦穗计数的平均绝对误差(MAE)、均方误差(MSE)和平均精确度(ACC)分别达到3.77、5.13和90.87%,相较于其他目标计数回归方法如MCNN(Multi-column convolutional neural network)、CSRnet(Congested scene recognition network)和WHCNETs (Wheat head counting networks)等,表现最佳。与基线网络P2Pnet相比,MAE和MSE分别降低23.2%和16.6%,ACC提高2.67个百分点。为了进一步验证本文算法的有效性,对采集的其它4种不同品种的小麦(AK1009、AK1401、AK1706和YKM222)进行了实验,实验结果显示,麦穗计数MAE和MSE平均为5.10和6.17,ACC也达到89.69%,表明本文提出的模型具有较好的泛化性能。

关键词：麦穗计数无人机图像 FE-P2Pnet FEM Wheat-ZWF数据集

壮骨关节丸联合依托考昔治疗早期膝骨关节炎的临床研究

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现代药物与临床 2024年第4期39卷 994-998页

作者：梁颖杰李飞雄许彪彪山西省汾阳医院骨科山西吕梁032200

目的探讨壮骨关节丸联合依托考昔治疗早期膝骨关节炎的临床疗效。方法选取2020年5月—2023年5月山西省汾阳医院收治84例的膝骨关节炎患者,依据随机数字表法分为对照组(42例)和治疗组(42例)。对照组口服依托考昔片,初始剂量为30mg/次,... 详细信息

目的探讨壮骨关节丸联合依托考昔治疗早期膝骨关节炎的临床疗效。方法选取2020年5月—2023年5月山西省汾阳医院收治84例的膝骨关节炎患者,依据随机数字表法分为对照组(42例)和治疗组(42例)。对照组口服依托考昔片,初始剂量为30mg/次,若2周后症状无明显缓解,剂量调整为60mg/次,1次/d。治疗组患者在对照组基础上口服壮骨关节丸,6g/次,2次/d。两组患者均连续治疗4周。观察两组患者临床疗效,比较治疗前后两组患者视觉模拟评分表(VAS)、Lysholm和SF-36评分,及血清白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)和高敏C反应蛋白(hs-CRP)水平。结果治疗后,治疗组总有效率为95.24%,明显高于对照组80.95%(P<0.05)。治疗后,两组VAS评分明显降低,而Lysholm评分明显升高(P<0.05),且治疗组评分均明显好于对照组(P<0.05)。治疗后,两组血清IL-6、TNF-α及hs-CRP水平均明显降低(P<0.05),且治疗组血清水平降低幅度明显大于对照组(P<0.05)。治疗后,两组SF-36各项维度评分均明显升高(P<0.05),且治疗组总体健康、躯体疼痛、生命活力、生理功能评分升高幅度大于对照组(P<0.05)。结论壮骨关节丸联合依托考昔治疗早期膝骨关节炎具有较好的治疗效果,可减轻患者的膝关节疼痛程度,改善膝关节功能、体内的炎症状态以及生活质量。

关键词：壮骨关节丸依托考昔片早期膝骨关节炎视觉模拟评分表肿瘤坏死因子-α 高敏C反应蛋白

痰热清注射液治疗慢性阻塞性肺病急性加重期作用机制探讨

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中医药临床杂志 2024年第6期36卷 1081-1087页

作者：谭标标任薇安徽中医药大学安徽合肥230031 安徽中医药大学第一附属医院安徽合肥230031

目的:研究痰热清注射液治疗慢性阻塞性肺病急性加重期作用机制。方法:在线查询TCMSP数据库、既往文献获取黄芩、熊胆粉、山羊角、金银花、连翘等中药的主要活性成分,利用swisstargetprediction数据库获取其活性成分对应靶点;利用GeneCa... 详细信息

目的:研究痰热清注射液治疗慢性阻塞性肺病急性加重期作用机制。方法:在线查询TCMSP数据库、既往文献获取黄芩、熊胆粉、山羊角、金银花、连翘等中药的主要活性成分,利用swisstargetprediction数据库获取其活性成分对应靶点;利用GeneCards、OMMI、Drug Bank等数据库获取慢性阻塞性肺病急性加重期靶点。利用Venny平台在线获取药物与疾病靶点交集,通过DAVID数据库对相交靶点进行基因本体分析和通路富集分析,使用STRING数据库构建蛋白相互作用网络,借助Cytoscapr软件行可视化处理并筛选主要活性成分、关键靶点。最后通过AutoDock vina软件将核心靶点与核心成分进行分子对接验证,并利用pymol可视化处理。结果:痰热清注射液中含主要活性成分90个,对应靶点557个;连翘、黄芩、金银花为痰热清注射液的关键作用药物;baicalein、Norwogonin、5,7,4’-Trihydroxy-8-methoxyflavone、5,2’,6’-Trihydroxy-7,8-dimethoxyflavone、(2R)-7-hydroxy-5-methoxy-2-phenylchroman-4-one、Panicolin、Skullcapflavone II、Moslosooflavone、5,7,2,5-tetrahydroxy-8,6-dimethoxyflavone、quercetin等为核心活性成分;STAT3、HSP90AA1、ESR1、SRC、EP300、AKT1、JUN、PIK3R1、RELA等靶点为蛋白互作网络中的核心靶点。结论:痰热清注射液治疗主要通过黄酮类物质调节细胞炎症反应、细胞增殖、凋亡等对慢性阻塞性肺病急性加重期发挥潜在作用。

关键词：痰热清注射液慢性阻塞性肺病急性加重期网络药理学分子对接技术作用机制