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Formation and solute segregation for an asymmetric tilt boundary on{1012}twin boundaries 被引量:1
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作者 Qiang Yang Shuhui Lv +3 位作者 Peng Chen Zefeng Xie Shuo Zhou Xin Qiu 《Journal of Magnesium and Alloys》 2025年第2期583-591,共9页
Asymmetric tilt boundaries on conventional twin boundaries(TBs)are significant for understanding the role of twins on coordinating plastic deformation in many metallic alloys.However,the formation modes of many asymme... Asymmetric tilt boundaries on conventional twin boundaries(TBs)are significant for understanding the role of twins on coordinating plastic deformation in many metallic alloys.However,the formation modes of many asymmetric tilt boundaries are hard to be accounted for based on traditional theoretical models,and the corresponding solute segregation is complex.Herein,atomic structures of a specific asymmetric boundary on{1012}TBs were reveled using aberration-corrected high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),molecular dynamics(MD)and density functional theory(DFT)simulations.Reaction between<a60>M dislocations and the{1012}TB can generate a~61°/25°asymmetric tilt boundary.The segregation of Gd and Zn atoms is closely related to the aggregateddislocations and the interfacial interstices of the asymmetric tilt boundary,which is energetically favorable in reducing the total system energy. 展开更多
关键词 Magnesium alloy Transmission electron microscopy twin boundary DISLOCATION SEGREGATION
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Interfacial precipitation in{1012}twin boundaries of a Mg-Gd-Zn-Zr alloy 被引量:3
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作者 Zixiang Yan Qiang Yang +5 位作者 Fanzhi Meng Rui Ma Rirong Bao Xiaojuan Liu Jian Meng Xin Qiu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第34期103-109,共7页
Twinning and precipitation play important roles in deformation and strengthening of magnesium alloys.In this work,interfacial precipitation in{1012}twin boundaries(TBs)of a cold-stamped Mg-12Gd-1.2Zn-0.4Zr alloy was i... Twinning and precipitation play important roles in deformation and strengthening of magnesium alloys.In this work,interfacial precipitation in{1012}twin boundaries(TBs)of a cold-stamped Mg-12Gd-1.2Zn-0.4Zr alloy was investigated using atomic-resolution high-angle annular dark-field scanning transmission electron microscopy.Extended periodic segregation of Gd+Zn atoms in the~86.2°{1012}TBs with basal-prismatic facets and in the symmetric tilting TBs(obviously>86.2°)frequently occurred,resulted in the formation of new interfacial phases,namelyβ_(TB)’having a monoclinic structure in the TBs with two segregation layers andβ_(TB) having a tetragonal structure in the TBs with three or more segregation layers.The formation ofβ_(TB) clearly accelerates peak-aging and improves the alloy’s strength. 展开更多
关键词 Magnesium alloys twinNING Scanning/transmission electron microscopy(STEM) SEGREGATION Interfacial precipitate
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Solute-solute interactions and their impacts on solute co-segregation and interfacial cohesion of{1012}twin boundary in zinc
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作者 Zhifeng Huang Jian-Feng Nie 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第7期117-128,共12页
Interactions of solute atoms in biodegradable zinc alloys and their effect on alloy mechanical properties have been less investigated.In this work,the interactions between the common solutes(Li,Mg,Mn,Cu,and Ag)used in... Interactions of solute atoms in biodegradable zinc alloys and their effect on alloy mechanical properties have been less investigated.In this work,the interactions between the common solutes(Li,Mg,Mn,Cu,and Ag)used in the biodegradable Zn alloys,including a solute-solute pair with the same element or with two different elements,are investigated based on first-principles calculations.It is found that the energetically favorable configuration is the third nearest-neighboring for most solute-solute pairs in the bulk lattice because of the relatively strong electronic interaction between solute and Zn atoms or the relatively small local elastic deformation associated with the configuration.Considering that interfacial cleavage is a key fracture mode of zinc,the segregation ability of these solutes and their effect on the{1012}twin boundary cohesion are also examined.The result shows that Li tends to fully occupy its preferred site in the twin boundary,while Mg,Mn,Cu,or Ag has a concentration limitation in the twin boundary.The twin boundary cohesion can be significantly enhanced by the segregation of Mn,followed by Cu and Ag,because of the contribution of their d states close to the Fermi level.Furthermore,the co-segregation ability of two solute atoms in the twin boundary increases with increasing the binding tendency of these two solute atoms in the boundary.Mn and Li or Mg show a relatively strong co-segregation ability in the twin boundary.Adding Mn to Zn-Li or Zn-Mg alloys can significantly enhance the resistance to fracture of twin boundaries. 展开更多
关键词 Zinc alloys twin boundary Solute-solute interaction Co-segregation Interfacial fracture
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植物乳植杆菌R1012调控TLR-4/NF-κB和Nrf2通路改善神经炎症与氧化应激:基于BV2/PC12细胞共培养模型的体外研究
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作者 李晶晶 周三华 +3 位作者 朱红敏 陈静 江晓东 刘修燕 《中国微生态学杂志》 北大核心 2025年第5期526-531,共6页
目的基于BV2/PC12细胞共培养模型,探究植物乳植杆菌(Lactiplantibacillus plantarum)R1012通过调控TLR-4/NF-κB和Nrf2信号通路缓解炎症和氧化应激的分子机制,及其对神经元损伤的改善作用。方法借助Transwell小室对BV2小胶质细胞和PC12... 目的基于BV2/PC12细胞共培养模型,探究植物乳植杆菌(Lactiplantibacillus plantarum)R1012通过调控TLR-4/NF-κB和Nrf2信号通路缓解炎症和氧化应激的分子机制,及其对神经元损伤的改善作用。方法借助Transwell小室对BV2小胶质细胞和PC12神经元细胞进行共培养,将扩增培养后的L.plantarum R1012以MOI=10添加于上室与BV2小胶质细胞进行24 h共培养,培养结束后对上室进行洗涤并添加LPS处理24 h,收集上室BV2细胞、下室上清液及PC12细胞,检测氧化应激标志物和相关活性酶的表达以及BV2、PC12细胞中目的基因和蛋白表达水平。将BV2细胞接种于12孔板中进行相同处理后收集上清液,检测上清液中炎症标志物水平。结果L.plantarum R1012通过调控TLR-4/NF-κB信号通路显著降低BV2细胞中炎症因子IL-6和TNF-α水平;同时通过调控Nrf2信号通路显著降低BV2细胞一氧化氮合酶水平,显著提高超氧化物歧化酶水平,进而降低氧化应激标志物过氧化氢和丙二醛水平,提高总抗氧化能力。L.plantarum R1012显著降低PC12细胞中BAX基因表达,显著提高BCL-2和GAP-43基因表达。结论L.plantarum R1012通过调控TLR-4/NF-κB和Nrf2信号通路发挥抗炎和抗氧化应激作用,并对细胞层面的神经元损伤具有一定的改善效果,为进一步研究其在孤独症谱系障碍中的潜在应用提供了实验依据。 展开更多
关键词 孤独症谱系障碍 神经炎症 氧化应激 植物乳植杆菌R1012
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锁定钢板联合Twin Tail Tightrope带袢钛板内固定治疗锁骨中段骨折合并同侧肩锁关节脱位6例临床分析
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作者 张德新 杨丹 +3 位作者 胡宏宇 赵丽英 高顺红 张云鹏 《中国骨与关节损伤杂志》 2025年第9期1000-1002,共3页
锁骨骨折是临床常见损伤,占全身骨折的2.6%~5.0%[1]。锁骨中段骨折约占锁骨骨折的80%[2],锁骨中段骨折合并同侧肩锁关节脱位则比较少见,此类损伤准确诊断、及时合理治疗是恢复肩关节功能的前提。笔者回顾性分析自2016-11—2022-10诊治的... 锁骨骨折是临床常见损伤,占全身骨折的2.6%~5.0%[1]。锁骨中段骨折约占锁骨骨折的80%[2],锁骨中段骨折合并同侧肩锁关节脱位则比较少见,此类损伤准确诊断、及时合理治疗是恢复肩关节功能的前提。笔者回顾性分析自2016-11—2022-10诊治的6例锁骨中段骨折合并同侧肩锁关节脱位,采用锁定钢板联合Twin Tail Tightrope带袢钛板内固定,总结临床体会,报道如下。1病例报道本组6例,男5例,女1例;年龄39~60岁,平均48.7岁。左侧4例,右侧2例。致伤原因:交通事故伤3例,骑摩托车摔伤2例,楼梯坠落伤1例。 展开更多
关键词 锁骨中段骨折 肩锁关节脱位 twin Tail Tightrope系统 带袢钛板 弹性固定
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Twin-PBL剪力连接件力学性能与结构参数优选
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作者 姚国文 董雨杭 +2 位作者 应立 贺煊博 吴树杭 《重庆交通大学学报(自然科学版)》 北大核心 2025年第2期1-9,共9页
波形钢腹板连续刚构桥是一种新型的桥梁结构形式,其结合了钢的高强度、强变形能力和混凝土的良好抗压性能,其剪力连接件的细部构造对整体承载能力有着决定性的影响。为深入探索Twin-PBL剪力连接件的力学行为,并通过细部构造优化来提高... 波形钢腹板连续刚构桥是一种新型的桥梁结构形式,其结合了钢的高强度、强变形能力和混凝土的良好抗压性能,其剪力连接件的细部构造对整体承载能力有着决定性的影响。为深入探索Twin-PBL剪力连接件的力学行为,并通过细部构造优化来提高其力学性能,基于ABAQUS建立了典型波形钢腹板箱梁节段的实体有限元模型,研究了波形钢腹板与混凝土顶板之间Twin-PBL剪力连接件的力学表现,揭示了横向贯穿钢筋构造的有无对Twin-PBL剪力连接件抗剪性能的影响规律,并对开孔钢板孔径、厚度及横向贯穿钢筋直径进行了结构参数优选。研究表明:Twin-PBL剪力连接件设置横向贯穿钢筋能够降低开孔钢板和钢翼缘板的剪应力,且贯穿钢筋分摊了孔洞内混凝土榫的部分剪力;综合考虑开孔钢板的材料属性、制作工艺等因素,对开孔钢板截面高度为180 mm的Twin-PBL连接件,最优开孔直径为70 mm,横向贯穿钢筋直径为25 mm,开孔钢板厚度为28 mm。 展开更多
关键词 桥梁工程 twin-PBL剪力连接件 力学性能 构造优化 波形钢腹板组合箱梁
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改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形效果评价
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作者 卢春燕 崔雪蕾 曹培培 《上海口腔医学》 2025年第2期152-156,共5页
目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),... 目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),对照组采用改良Twin-block矫治器,试验组采用改良Twin-block矫治器联合微种植体支抗。比较2组矫治时间、咬合打开时间、排列整齐时间、上下牙槽座角(ANB)、下牙槽座角(SNB)、上牙槽座角(SNA)、上中切牙长轴与NA连线的夹角(U1-NA)、下中切牙长轴与NA连线的夹角(U1-NB)、上颌中切牙长轴与前颅底平面夹角(U1-SN)、下颌中切牙长轴与下颌平面的后上交角(L1-MP)、上颌唇突度(ULP)、下颌唇突度(LLP)、上下唇突点与颏前点切线和眼耳平面夹角(Z角)、菌斑指数(PLI)、牙龈指数(GI)和龈沟出血指数(SBI)。记录并发症及患者满意度。采用SPSS 24.0软件包对数据进行统计学分析。结果:试验组患者矫治时间、咬合打开时间及排列整齐时间显著少于对照组(P<0.05)。治疗后,2组ANB、U1-NA和U1-SN小于治疗前,试验组显著小于对照组(P<0.05);U1-NB、L1-MP大于治疗前,试验组显著大于对照组(P<0.05);SNB、SNA相比无显著差异(P>0.05)。治疗后,2组ULP、LLP低于治疗前,试验组显著低于对照组(P<0.05);Z角升高,试验组显著高于对照组(P<0.05);PLI低于治疗前,试验组显著低于对照组(P<0.05);GI、SBI相比无显著差异(P>0.05)。2组患者满意度相比无显著差异(P>0.05)。结论:改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形,有助于缩短矫治时间,改善颌骨及面部软组织轮廓,促进牙美学效果的恢复。 展开更多
关键词 错[牙合]畸形 安氏Ⅱ类1分类错[牙合] 改良twin-block矫治器 微种植体支抗
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Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果比较
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作者 黄飞 陈倩 张胜男 《中国现代医学杂志》 2025年第6期6-11,共6页
目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,... 目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,每组36例。对照组接受Twin-block功能矫治器联合自锁托槽治疗,研究组接受Pass矫治器治疗。对比两组临床疗效、颌牙排齐时间、硬组织头影测量指标[上中切牙轴与蝶鞍中心-鼻根点平面夹角(U1-SN)、下中切牙轴与鼻根点-上齿槽座点连接角(U1-NA)、上齿槽座点、鼻根点及下次槽座点连接角(ANB)、蝶鞍中心、鼻根点及上齿槽座点连接角(SNA)]、软组织头影测量目标[上唇到审美平面距离(TUL-FP)、下唇H线距、下唇到审美平面距离(TLL-FP)、鼻唇角]、矫治效果及患者满意度。结果研究组总有效率高于对照组(P<0.05)。研究组上颌牙排齐时间和下颌牙排齐时间均短于对照组(P<0.05)。两组治疗前后U1-SN、ANB、SNA、SNB的差值比较,差异无统计学意义(P>0.05)。研究组治疗前后U1-NA的差值高于对照组(P<0.05)。研究组治疗前后下唇H线距、TUL-FP、鼻唇角、TLL-FP的差值高于对照组(P<0.05)。研究组治疗前后同行评估等级指数(PAR)评分的差值高于对照组(P<0.05)。研究组满意度高于对照组(P<0.05)。结论相比于Twin-block功能矫治器联合自锁托槽,Pass矫治器治疗安氏Ⅱ类1分类错[牙合]畸形患者效果确切,可提高矫治效果,改善面部侧貌美学,缩短颌牙排齐时间,且患者满意度较高。 展开更多
关键词 安氏Ⅱ类1分类错[牙合]畸形 Pass矫治器 twin-BLOCK功能矫治器 自锁托槽 矫正效果
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安氏Ⅱ类错[牙合]畸形佩戴Twin-block矫治器时上颌骨的应力分布 被引量:1
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作者 李帅 刘桦 +3 位作者 商永慧 刘义琮 赵启航 刘文 《中国组织工程研究》 CAS 北大核心 2025年第5期881-887,共7页
背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨... 背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨缝及上颌牙列的应力分布。方法:选择在山东省康复大学青岛医院/青岛市市立医院口腔正畸科进行正畸治疗的安氏Ⅱ类错[牙合]畸形患者1例,测量患者佩戴Twin-block矫治器时的咬合力数据,采集其锥形束CT数据,建立包含上颌骨复合体、周边各骨缝、Twin-block矫治器及上颌牙列在内的有限元模型,通过ABAQUS软件模拟患者戴入Twin-block时上颌骨、骨缝及上颌牙列的应力分布与位移。结果与结论:①上颌前牙受到的等效应力明显小于后牙,两侧牙齿的最大等效应力分别为4.7975 MPa和8.7161 MPa,均位于第一前磨牙处;最大位移呈现在两侧上颌切牙处,分别为0.0805 mm和0.0810 mm;②骨缝的最大等效应力为1.284 MPa,主要集中在两侧翼腭缝及额颌缝,其余骨缝受力情况几乎无差异;骨缝的最大位移为0.07 mm,其中翼腭缝的位移量最大,其次是额颌缝;③上颌骨复合体受到的最大等效应力为27.18 MPa,主要集中在上颌骨前面梨状孔两侧、鼻额缝周边及颚骨后部翼腭缝附近;上颌骨的最大位移值为0.07 mm,主要集中于上颌牙槽骨;④结果显示,咬合力通过Twin-block矫治器作用于上颌骨复合体,导致上颌骨顺时针旋转、牙合平面变陡,应采取相应措施补偿这种趋势,例如建牙合过程中考虑上颌磨牙伸长、下颌磨牙压低,不仅能够将牙合平面整平,同时有利于下颌前伸,这将进一步提高Ⅱ类错[牙合]正畸治疗效果。 展开更多
关键词 错牙合畸形 组织构建 骨组织工程 twin-BLOCK矫治器 功能矫治 有限元分析
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{1012}孪晶对AZ31镁合金腐蚀性能的影响 被引量:1
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作者 赵晓隆 郝晓博 杨杰 《材料科学与工艺》 北大核心 2025年第4期72-80,共9页
镁及其合金因具有质轻、高强和良好阻尼性能等优点,被广泛应用于航空航天、交通和消费电子领域。但镁及其合金的高化学活性使其易在潮湿环境下发生腐蚀,增加服役失效风险,极大限制了镁及其合金的工业应用。大量的研究表明,晶粒尺寸对镁... 镁及其合金因具有质轻、高强和良好阻尼性能等优点,被广泛应用于航空航天、交通和消费电子领域。但镁及其合金的高化学活性使其易在潮湿环境下发生腐蚀,增加服役失效风险,极大限制了镁及其合金的工业应用。大量的研究表明,晶粒尺寸对镁合金的耐蚀性有重要的影响。本文通过预压缩变形在AZ31镁合金中引入大量{1012}孪晶界面,以细化镁合金的初始组织,探究由孪晶界面的引入带来的细晶效应与AZ31镁合金耐蚀性之间的关联。结果表明:随变形量增加,AZ31镁合金中孪晶体积分数逐渐提高,晶粒尺寸先减小后增大,同时初始{0001}织构逐渐转变为{1010}和{1012}织构,AZ31镁合金轧制面的耐蚀性能随着预变形量的增加而逐渐降低。分析表明,{1012}孪晶导致的镁合金耐蚀性能的降低与孪晶诱导织构的改变有关。相较于晶粒尺寸,晶体取向的改变对AZ31镁合金的腐蚀性能影响更为显著。 展开更多
关键词 AZ31镁合金 孪晶 变形量 腐蚀性能 织构
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Joint Estimation of SOH and RUL for Lithium-Ion Batteries Based on Improved Twin Support Vector Machineh 被引量:1
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作者 Liyao Yang Hongyan Ma +1 位作者 Yingda Zhang Wei He 《Energy Engineering》 EI 2025年第1期243-264,共22页
Accurately estimating the State of Health(SOH)and Remaining Useful Life(RUL)of lithium-ion batteries(LIBs)is crucial for the continuous and stable operation of battery management systems.However,due to the complex int... Accurately estimating the State of Health(SOH)and Remaining Useful Life(RUL)of lithium-ion batteries(LIBs)is crucial for the continuous and stable operation of battery management systems.However,due to the complex internal chemical systems of LIBs and the nonlinear degradation of their performance,direct measurement of SOH and RUL is challenging.To address these issues,the Twin Support Vector Machine(TWSVM)method is proposed to predict SOH and RUL.Initially,the constant current charging time of the lithium battery is extracted as a health indicator(HI),decomposed using Variational Modal Decomposition(VMD),and feature correlations are computed using Importance of Random Forest Features(RF)to maximize the extraction of critical factors influencing battery performance degradation.Furthermore,to enhance the global search capability of the Convolution Optimization Algorithm(COA),improvements are made using Good Point Set theory and the Differential Evolution method.The Improved Convolution Optimization Algorithm(ICOA)is employed to optimize TWSVM parameters for constructing SOH and RUL prediction models.Finally,the proposed models are validated using NASA and CALCE lithium-ion battery datasets.Experimental results demonstrate that the proposed models achieve an RMSE not exceeding 0.007 and an MAPE not exceeding 0.0082 for SOH and RUL prediction,with a relative error in RUL prediction within the range of[-1.8%,2%].Compared to other models,the proposed model not only exhibits superior fitting capability but also demonstrates robust performance. 展开更多
关键词 State of health remaining useful life variational modal decomposition random forest twin support vector machine convolutional optimization algorithm
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Artificial Intelligence-Enhanced Digital Twin Systems Engineering Towards the Industrial Metaverse in the Era of Industry 5.0 被引量:3
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作者 He Zhang Yilin Li +2 位作者 Shuai Zhang Lukai Song Fei Tao 《Chinese Journal of Mechanical Engineering》 2025年第2期98-119,共22页
With the continuous advancement and maturation of technologies such as big data,artificial intelligence,virtual reality,robotics,human-machine collaboration,and augmented reality,many enterprises are finding new avenu... With the continuous advancement and maturation of technologies such as big data,artificial intelligence,virtual reality,robotics,human-machine collaboration,and augmented reality,many enterprises are finding new avenues for digital transformation and intelligent upgrading.Industry 5.0,a further extension and development of Industry 4.0,has become an important development trend in industry with more emphasis on human-centered sustainability and flexibility.Accordingly,both the industrial metaverse and digital twins have attracted much attention in this new era.However,the relationship between them is not clear enough.In this paper,a comparison between digital twins and the metaverse in industry is made firstly.Then,we propose the concept and framework of Digital Twin Systems Engineering(DTSE)to demonstrate how digital twins support the industrial metaverse in the era of Industry 5.0 by integrating systems engineering principles.Furthermore,we discuss the key technologies and challenges of DTSE,in particular how artificial intelligence enhances the application of DTSE.Finally,a specific application scenario in the aviation field is presented to illustrate the application prospects of DTSE. 展开更多
关键词 Digital twins Systems engineering Industrial metaverse Artificial intelligence Industry 5.0 Smart manufacturing
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3种不同类型Twin-block矫治器对前牙应力分布和位移的影响
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作者 李星雨 张春艳 +8 位作者 李希贝 黄文莉 于少洋 杨文科 张映玥 郭骏 阎潇 张强 袁晓 《医用生物力学》 北大核心 2025年第4期844-850,共7页
目的 研究3种不同类型Twin-block矫治器对前牙、牙周膜及牙槽骨应力及位移的影响。方法 构建上下颌骨、关节盘、牙列及牙周膜的三维有限元模型。3组不同类型Twin-block矫治器的有限元模型分别为传统Twin-block矫治器、带切牙帽Twin-bloc... 目的 研究3种不同类型Twin-block矫治器对前牙、牙周膜及牙槽骨应力及位移的影响。方法 构建上下颌骨、关节盘、牙列及牙周膜的三维有限元模型。3组不同类型Twin-block矫治器的有限元模型分别为传统Twin-block矫治器、带切牙帽Twin-block矫治器、改良隐形Twin-block矫治器(clear twin-block aligner, CTBA)。所有类型矫治器的斜面角度均为70°,双侧分别加载200 N垂直于斜面的力。利用有限元方法分析前牙的应力分布与位移差异。结果 3种不同类型Twin-block矫治器均会导致上前牙舌倾及下前牙唇倾。CTBA组上前牙舌向位移及应力最大,最大应力为30.6 MPa,而下前牙唇向位移及应力最小,位移约为0.02 mm。同时CTBA组下前牙、牙周膜及牙槽骨所受等效应力在3组中最低,而传统Twin-block矫治器组最高。结论 在使用传统Twin-block矫治器治疗安氏Ⅱ类错[牙合]时,无论有无切牙帽,均会导致下前牙的唇倾;而与传统Twin-block矫治器相比,CTBA可减少对下前牙、牙槽骨、牙周膜应力和位移的影响,进而减小下前牙的牙周风险,但需注意上前牙舌向位移带来的舌倾效应。 展开更多
关键词 twin-BLOCK矫治器 功能矫治 隐形矫治器 安氏Ⅱ类错[牙合] 前牙
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Introducing high-density growth twins in aluminum alloys by laser surface remelting via templated nucleation of grains 被引量:1
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作者 Chunfeng Ma Qinglong Zhao +2 位作者 Xiao Liu Yanjun Li Qichuan Jiang 《Journal of Materials Science & Technology》 2025年第10期315-324,共10页
It is difficult to generate coherent twin boundaries in bulk Al alloys due to their high intrinsic stacking fault energy. Here, we report a strategy to induce high-density growth twins in aluminum alloys through the h... It is difficult to generate coherent twin boundaries in bulk Al alloys due to their high intrinsic stacking fault energy. Here, we report a strategy to induce high-density growth twins in aluminum alloys through the heterogeneous nucleation of twinned Al grains on twin-structured TiC nucleants and the preferred growth of twinned dendrites by laser surface remelting of bulk metals. The solidification structure at the surface shows a mixture of lamellar twinned dendrites with ultra-fine twin boundary spacing (∼2 µm), isolated twinned dendrites, and regular dendrites. EBSD analysis and finite element method (FEM) simulations have been used to understand the competitive growth between twinned and regular dendrites, and the solidification conditions for the preferred growth of twinned dendrites during laser remelting and subsequent rapid solidification are established. It is shown that the reduction in the ratio of temperature gradient G to solidification rate V promotes the formation of lamellar twinned dendrites. The primary trunk spacing of lamellar twinned dendrites is refined by the high thermal gradient and solidification rate. The present work paves a new way to generate high-density growth twins in additive-manufactured Al alloys. 展开更多
关键词 Heterogeneous nucleation twinned dendrites Solidification Aluminum alloys
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A Multi-Level Semantic Constraint Approach for Highway Tunnel Scene Twin Modeling 被引量:1
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作者 LI Yufei XIE Yakun +3 位作者 CHEN Mingzhen ZHAO Yaoji TU Jiaxing HU Ya 《Journal of Geodesy and Geoinformation Science》 2025年第2期37-56,共20页
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge... As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes. 展开更多
关键词 highway tunnel twin modeling multi-level semantic constraints tunnel vehicles multidimensional modeling
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An optimization framework for hot-rolled strip crown control based on model-driven digital twin 被引量:1
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作者 Fen-jia Wang Chao Liu +6 位作者 An-rui He Yong Song Jian Shao Chi-huan Yao Yi Qiang Hong-yan Liu Bo Ma 《Journal of Iron and Steel Research International》 2025年第7期1920-1939,共20页
Accurate crown control is paramount for ensuring the quality of hot-rolled strip products.Given the multitude of influencing parameters and the intricate coupling and genetic relationships among them,the conventional ... Accurate crown control is paramount for ensuring the quality of hot-rolled strip products.Given the multitude of influencing parameters and the intricate coupling and genetic relationships among them,the conventional crown control method is no longer sufficient to meet the precision requirements of schedule-free rolling.To address this limitation,an optimization framework for hot-rolled strip crown control was developed based on model-driven digital twin(MDDT).This framework enhances the strip crown control precision by facilitating collaborative operations among physical entities,virtual models,and functional application layers.In virtual modeling,a data-driven approach that integrates the extreme gradient boosting and the improved Harris hawk optimization algorithm was firstly proposed to fit the relationship between key process parameters and strip crown,and a global-local collaborative training strategy was proposed to enhance the model adaptability to diverse working conditions.Subsequently,the influence of crucial process factors on the virtual model was examined through model responses.Furthermore,a novel optimization mode for crown control based on MDDT was established by aligning and reconstructing both the physical and virtual models,thereby enhancing the crown control precision.Finally,data trials were conducted to validate the effectiveness of the proposed framework.The results indicated that the proposed method exhibited satisfactory performance and could be effectively utilized to improve the crown control precision. 展开更多
关键词 Hot-rolled strip Crown control Machine learning Digital twin Extreme gradient boosting
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High ductility induced by twin-assisted grain rotation and merging in solid-state cold spray additive manufactured Cu 被引量:1
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作者 Wenya Li Jingwen Yang +2 位作者 Zhengmao Zhang Yingchun Xie Chunjie Huang 《Journal of Materials Science & Technology》 2025年第11期11-15,共5页
1.Introduction.Cold Spray(CS)is a highly advanced solid-state metal depo-sition process that was first developed in the 1980s.This innovative technique involves the high-speed(300-1200 m/s)impact deposition of micron-... 1.Introduction.Cold Spray(CS)is a highly advanced solid-state metal depo-sition process that was first developed in the 1980s.This innovative technique involves the high-speed(300-1200 m/s)impact deposition of micron-sized particles(5-50μm)to fabricate coatings[1-3].CS has been extensively used in a variety of coating applications,such as aerospace,automotive,energy,medical,marine,and others,to provide protection against high temperatures,corrosion,erosion,oxidation,and chemicals[4,5].Nowadays,the technical interest in CS is twofold:(i)as a repair process for damaged components,and(ii)as a solid-state additive manufacturing process.Compared to other fusion-based additive manufacturing(AM)technologies,Cold Spray Additive Manufacturing(CSAM)is a new member of the AM family that can enable the fabrication of deposits without undergoing melting.The chemical composition has been largely preserved from the powder to the deposit due to the minimal oxidation.The significant advantages of CSAM over other additive manufacturing processes include a high production rate,unlimited deposition size,high flexibility,and suitability for repairing damaged parts. 展开更多
关键词 additive manufacturing DUCTILITY cold spray MERGING solid state deposition twin assisted grain rotation
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Segregation behaviors in{101^(-)1}compressive twin boundaries of Mg-RE alloy under deformation at room temperature 被引量:1
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作者 Yujie Cui Lili Guo +6 位作者 Yunwei Gui Kenta Aoyagi Haotian Tong Qinqin Wei Fangzhou Liu Yuichiro Hayasaka Akihiko Chiba 《Journal of Magnesium and Alloys》 2025年第1期330-337,共8页
Solute atoms and precipitates significantly influence the mechanical properties of Mg alloys.Previous studies have mainly focused on the segregation behaviors of Mg alloys after annealing.In this study,we investigated... Solute atoms and precipitates significantly influence the mechanical properties of Mg alloys.Previous studies have mainly focused on the segregation behaviors of Mg alloys after annealing.In this study,we investigated the segregation behaviors of an Mg-RE alloy under deformation.We found that the enrichment of solute atoms occurred in{101^(-)1}compressive twin boundaries under compression at 298 K without any annealing in an Mg-RE alloy by scanning transmission electron microscopy and energy-dispersive X-ray analysis.The segregated solutes and precipitates impeded the twin growth,partially contributing to the formation of small-sized{101^(-)1}compressive twins.This research indicates the twin boundaries can be strengthened by segregated solutes and precipitates formed under deformation at room temperature. 展开更多
关键词 Magnesium alloys Compression test Scanning/transmission electron microscopy(STEM) SEGREGATION twin boundaries
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Twin-block功能矫治器与肌激动器对安氏Ⅱ类下颌后缩的矫治效果对比 被引量:1
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作者 杨宇虹 张静 +2 位作者 孙留振 刘耀冉 姜龙龙 《临床医学工程》 2025年第3期279-282,共4页
目的 对比分析Twin-block功能矫治器与肌激动器在安氏Ⅱ类下颌后缩患者矫治中的应用效果。方法 回顾性分析2020年1月至2024年1月我院收治的80例安氏Ⅱ类下颌后缩患者的临床资料,将采用Twin-block功能矫治器矫治的40例患者设为Twin-block... 目的 对比分析Twin-block功能矫治器与肌激动器在安氏Ⅱ类下颌后缩患者矫治中的应用效果。方法 回顾性分析2020年1月至2024年1月我院收治的80例安氏Ⅱ类下颌后缩患者的临床资料,将采用Twin-block功能矫治器矫治的40例患者设为Twin-block组,采用肌激动器矫治的40例患者设为肌激组。比较两组的矫治效果以及矫治8个月后的上气道矢状径[硬腭平面上气道矢状径(AP-hp)、软腭尖平面上气道矢状径(AP-sp)、会厌尖平面上气道矢状径(AP-te)]和舌骨位置[舌骨点至后鼻棘点距离(H-PNS)、舌骨点至锥前平面距离(H-CVP)、舌骨点至下颌平面距离(H-MP)、舌骨点至腭平面距离(H-PP)],并比较两组患者的主观感受情况。结果 Twin-block组的矫治总有效率(90.00%)与肌激组(80.00%)对比,差异无统计学意义(P>0.05)。矫治8个月后,Twin-block组的AP-hp、 AP-sp、 AP-te、 H-PNS、 H-CVP、 H-MP、 H-PP均大于肌激组(P <0.05);Twin-block组的佩戴顺利、舒适性、依从性和美观度评分均低于肌激组(P <0.05)。结论 Twin-block功能矫治器与肌激动器用于矫治安氏Ⅱ类下颌后缩的效果相当,但Twin-block功能矫治器能更有效地矫正安氏Ⅱ类下颌后缩患者的舌骨位置,改善患者的气道形态,而肌激动器矫治患者的主观感受更好。 展开更多
关键词 安氏Ⅱ类下颌后缩 twin-BLOCK功能矫治器 肌激动器 上气道矢状径 舌骨位置 主观感受
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Digital twin outlook for all-vanadium redox flow batteries
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作者 WANG Erqiang SANG Tengteng 《中国科学院大学学报(中英文)》 北大核心 2025年第5期577-588,共12页
Redox flow batteries have gained wide attention at home and abroad as a long-duration energy storage technology with the advantages of high safety,long lifespan,mutual independence of capacity and power,and easy recyc... Redox flow batteries have gained wide attention at home and abroad as a long-duration energy storage technology with the advantages of high safety,long lifespan,mutual independence of capacity and power,and easy recycling.However,the current battery management technology faces significant challenges,and there is room for development.Digital twin(DT),as a technology that collectively senses,evaluates,predicts,and optimizes characteristics,is promising to contribute to redox flow batteries’operation,maintenance,and management.This paper begins with a brief description of redox flow batteries,followed by a short explanation of the concept and application of DTs.DTs have already made some progress in the field of batteries,and can be applied to solve the problems of redox flow batteries in terms of thermal management and system optimization.Finally,the paper analyzes the combination of redox flow battery and DT architecture,which is expected to contribute to developing DT technology for redox flow batteries. 展开更多
关键词 redox flow battery digital twin battery management system
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