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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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Atomic scale structural characterization of{1012}twin boundaries in zinc 被引量:2
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作者 Hai-chen WU You-xing YU Xiao-fang BI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第8期1538-1542,共5页
The structure and the migration mechanisms of{1012}twin boundaries(TBs)of pure zinc deformed by rolling were studied using high-resolution transmission electron microscopy(HRTEM)at atomic scale.We found the presence o... The structure and the migration mechanisms of{1012}twin boundaries(TBs)of pure zinc deformed by rolling were studied using high-resolution transmission electron microscopy(HRTEM)at atomic scale.We found the presence of basal/prismatic(BP/PB)planes serrations on{1012}TBs and the coexistence of two kinds of TBs with different structures in the same{1012}twin:TBs composed of{1012}coherent twin boundaries(CTBs)plus short BP/PB serrations,and TBs composed of successive BP/PB segments without{1012}CTBs.The formation of BP/PB serrations has no relation to the c/a ratio of hexagonal-closepacked(HCP)metals because the BP/PB serrations are energetically preferred and geometrically favored.Based on dislocation theory,we proposed the migration mechanisms of the TBs to be the glide of twinning dislocations(TDs)on the CTBs and the climb of interface dislocations(IDs)on the BP/PB segments. 展开更多
关键词 ZINC twin boundaries basal/prismatic BP/PB serrations inigration mechanism high-resolution translnission electron inicroscopy(HRTEM)
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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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Hybrid AI-IoT Framework with Digital Twin Integration for Predictive Urban Infrastructure Management in Smart Cities
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作者 Abdullah Alourani Mehtab Alam +2 位作者 Ashraf Ali Ihtiram Raza Khan Chandra Kanta Samal 《Computers, Materials & Continua》 2026年第1期462-493,共32页
The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often... The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often advanced one dimension—such as Internet of Things(IoT)-based data acquisition,Artificial Intelligence(AI)-driven analytics,or digital twin visualization—without fully integrating these strands into a single operational loop.As a result,many existing solutions encounter bottlenecks in responsiveness,interoperability,and scalability,while also leaving concerns about data privacy unresolved.This research introduces a hybrid AI–IoT–Digital Twin framework that combines continuous sensing,distributed intelligence,and simulation-based decision support.The design incorporates multi-source sensor data,lightweight edge inference through Convolutional Neural Networks(CNN)and Long ShortTerm Memory(LSTM)models,and federated learning enhanced with secure aggregation and differential privacy to maintain confidentiality.A digital twin layer extends these capabilities by simulating city assets such as traffic flows and water networks,generating what-if scenarios,and issuing actionable control signals.Complementary modules,including model compression and synchronization protocols,are embedded to ensure reliability in bandwidth-constrained and heterogeneous urban environments.The framework is validated in two urban domains:traffic management,where it adapts signal cycles based on real-time congestion patterns,and pipeline monitoring,where it anticipates leaks through pressure and vibration data.Experimental results show a 28%reduction in response time,a 35%decrease in maintenance costs,and a marked reduction in false positives relative to conventional baselines.The architecture also demonstrates stability across 50+edge devices under federated training and resilience to uneven node participation.The proposed system provides a scalable and privacy-aware foundation for predictive urban infrastructure management.By closing the loop between sensing,learning,and control,it reduces operator dependence,enhances resource efficiency,and supports transparent governance models for emerging smart cities. 展开更多
关键词 Smart cities digital twin AI-IOT framework predictive infrastructure management edge computing reinforcement learning optimization methods federated learning urban systems modeling smart governance
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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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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 被引量:2
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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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On the strengthening and slip activity of Mg-3Al-1Zn alloy with pre-induced{1012¯}twins 被引量:2
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作者 Jie Kuang Yuqing Zhang +3 位作者 Xinpeng Du Jinyu Zhang Gang Liu Jun Sun 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第4期1292-1307,共16页
{1012¯}twins were introduced into the magnesium(Mg)plate AZ31 via pre-rolling along its transverse direction.The plates,both with and without the pre-induced{1012¯}twins,were subjected to uniaxial tension al... {1012¯}twins were introduced into the magnesium(Mg)plate AZ31 via pre-rolling along its transverse direction.The plates,both with and without the pre-induced{1012¯}twins,were subjected to uniaxial tension along different directions.Using crystal plasticity modeling,we found that the strengthening effect of the pre-induced{1012¯}twins on the macroscopic flow stress primarily arised from the increased slip resistance caused by the boundaries,rather than the orientation hardening due to the twinning reorientation(although the latter did make its contribution in some specific loading directions).Besides,the pre-existing{1012¯}twins were found,by both experiments and simulation,to promote the activity of prismatic and pyramidal<c+a>in the parent matrix of the material.Further analysis showed that the enhanced non-basal slip activity is related to the{1012¯}twin boundaries’low micro Hall-Petch slope ratios of non-basal slips to basal slip.With the critical resolved shear stress(CRSS)obtained from crystal plasticity modeling and the orientation data from EBSD,a probability-based slip transfer model was proposed.The model predicts higher slip transfer probabilities and thus lower strain concentration tendencies at{1012¯}twin boundaries than that at grain boundaries,which agrees with the experimental observation that the strain localization was primarily associated with the latter.The present findings are helpful scientifically,in deepening our understanding of how the pre-induced{1012¯}twins affect the strength and slip activity of Mg alloys,and technologically,in guiding the design of the pre-strain protocol of Mg alloys. 展开更多
关键词 Mg alloy {1012¯}twins Strengthening Slip activity Micro Hall-Petch effect
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Atomic-resolution studies on reactions between basal dislocations and {1012} coherent twin boundaries in a Mg alloy 被引量:3
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作者 Huhu Su Xinzhe Zhou +2 位作者 Shijian Zheng Hengqiang Ye Zhiqing Yang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第7期28-35,共8页
Reactions between basal 〈a60〉 dislocations and {1012} coherent twin boundaries(CTBs) in a Mg alloy were studied with atomic resolution. Individual dislocation-CTB reactions produced steps with residual dislocations ... Reactions between basal 〈a60〉 dislocations and {1012} coherent twin boundaries(CTBs) in a Mg alloy were studied with atomic resolution. Individual dislocation-CTB reactions produced steps with residual dislocations and multiple t winnin g dislocations(TDs) gliding away, consequently resulting in TB migration. Reactions between {1012} CTBs and low-angle grain boundaries composed of basal 〈a60〉 dislocations created either basal-prismatic/prismatic-basal interfaces or asymmetric tilt grain boundaries, depending on whether TDs gliding away or not. Not only the emission of TDs by dislocation-TB reactions may drive TB migration, but also the resultant steps or facets along TBs can act as TD sources to facilitate TB migration. Our results indicate that roughness or severe loss of local coherency induced by dislocation-TB reactions does not intrinsically impede TB migration in Mg alloys. Dislocation-TB reactions may provide another feasible strategy to improve the ductility of Mg alloys, in addition to other techniques like grain refinement and texture modification. 展开更多
关键词 Mg alloys DISLOCATION twin boundary Migration Plastic deformation
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Active{1121}and{1012}extension twinning in a WE43 Mg alloy 被引量:4
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作者 W.Q.Chen S.Deng +1 位作者 X.J.Zhao S.N.Luo 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第13期93-101,共9页
Deformation twinning in a WE43 alloy subjected to uniaxial compression at room temperature is in-vestigated.Active{1121}and{1012}extension twinning is observed.The activation of{1121}twinning in a certain grain is inf... Deformation twinning in a WE43 alloy subjected to uniaxial compression at room temperature is in-vestigated.Active{1121}and{1012}extension twinning is observed.The activation of{1121}twinning in a certain grain is influenced not only by its own Schmid factor,but also by that of the basal slip.Twin-twin interactions of the co-zone{1121}twin variants are commonly observed and systematically studied,including the crystallographic characteristics of the four typically observed twin-twin junctions(TTJs)and the associated twin-twin boundaries.Unlike the quilted-looking TTJs formed by the interaction of co-zone{1012}twin variants,crossing-like TTJs of co-zone{1121}twin variants are observed and their formation mechanisms are discussed.Crossing-like TTJs are also formed by the interaction of{1121}and{10¯12}twins.The morphology and thickening rate of{1121}and{1012}twins vary markedly due to the difference in twinning shear.The needle-like{1121}twins thicken more slowly than the lenticular{1012}twins.Twin nucleation is observed on the previously formed{1121}twin boundary due to the relatively large strain concentration on such interface,while twin nucleation on{1012}twin boundary is rarely observed. 展开更多
关键词 Mg alloy Plastic deformation twinNING twin-twin interaction twin-twin junction
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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 被引量:1
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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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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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Twin-block矫治器治疗青少年骨性Ⅱ类错[牙合]畸形的效果及对上气道体积的影响
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作者 詹育香 《临床医学研究与实践》 2025年第36期50-53,共4页
目的研究Twin-block矫治器治疗青少年骨性Ⅱ类错[牙合]畸形的效果及对上气道体积的影响。方法选择2023年7月至2024年9月在本院接受治疗的40例青少年骨性Ⅱ类错[牙合]畸形患者,随机将其分为研究组(n=20,Twin-block矫治器)与对照组(n=20,... 目的研究Twin-block矫治器治疗青少年骨性Ⅱ类错[牙合]畸形的效果及对上气道体积的影响。方法选择2023年7月至2024年9月在本院接受治疗的40例青少年骨性Ⅱ类错[牙合]畸形患者,随机将其分为研究组(n=20,Twin-block矫治器)与对照组(n=20,无托槽隐形矫治器)。比较两组治疗前、后的头颅侧位片X线测量结果、上气道矢状径指标及治疗满意度。结果研究组治疗后的头颅侧位片X线测量结果[蝶鞍点-鼻根点-下牙槽座点角(SNB)、蝶鞍点-鼻根点-上牙槽座点角(SNA)、上牙槽座点-鼻根点-下牙槽座点角(ANB)]优于对照组(P<0.05)。研究组治疗后的上气道矢状径指标(鼻咽后壁至基底的矢状径、软腭后缘至咽后壁的矢状径、第一磨牙间矢状径、上颌骨后壁至中线矢状径、下颌骨后壁至中线矢状径)大于对照组(P<0.05)。研究组的治疗满意度高于对照组(P<0.05)。结论Twin-block矫治器、无托槽隐形矫治器均对青少年骨性Ⅱ类错[牙合]畸形患者有一定治疗效果,但前者能够显著改善患者的面部侧貌及上气道体积,且满意度较高。 展开更多
关键词 骨性Ⅱ类错[牙合]畸形 twin-BLOCK矫治器 青少年 隐形矫治器 上气道体积
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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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新型固定式Twin-block矫治器治疗青春期骨性Ⅱ类错[牙合]畸形的疗效分析 被引量:1
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作者 丁盟 张薇 +5 位作者 沈群 陈玉成 张慧 葛非凡 杭梦月 吴建华 《上海口腔医学》 2025年第3期291-297,共7页
目的:评价一种新型固定式Twin-block矫治器治疗青春期骨性Ⅱ类错[牙合]畸形的临床疗效。方法:选择年龄10~13岁的骨性Ⅱ类下颌骨后缩患者21例,使用一种新型固定式Twin-block矫治器进行功能矫形治疗,治疗前后拍摄全景片及头颅侧位片并进... 目的:评价一种新型固定式Twin-block矫治器治疗青春期骨性Ⅱ类错[牙合]畸形的临床疗效。方法:选择年龄10~13岁的骨性Ⅱ类下颌骨后缩患者21例,使用一种新型固定式Twin-block矫治器进行功能矫形治疗,治疗前后拍摄全景片及头颅侧位片并进行头影测量。结果:治疗过程中未出现矫治器松动、脱落,平均疗程为(11.42±1.78)个月。治疗前后矢状向测量指标中,下颌骨位置(SNB)、下颌骨综合长度(Co-Gn)、鼻唇角(Cm-Sn-UL)、髁突矢状向位置(Pcd-S)、下唇突度(LL-SnPg)显著增大(P<0.05);上下颌骨相对位置(ANB)、Y轴角(SGn/FH)、上前牙倾斜度(U1/SN)、颏唇沟深度(Si-LLPg')显著减小(P<0.05);上颌骨位置(SNA)、下颌后部位置(S Vert-Co)、下颌体长度(Go'-Me)、下前牙倾斜度(IMPA),上下中切牙角度(U1/L1)、上唇突度(UL-SnPg')的差异无统计学意义(P>0.05)。垂直向测量指标除后面高(S-Go')、上前牙垂直向距离(U1-PP)、平面角(SN/OP)、下颌高度(Ar-Go')、下颌支高度(Co-Go)显著增加外(P<0.05),下牙列垂直向位置(Ll-MP、L6-MP)、上后牙垂直向距离(U6-PP)、前面高(N-Me)、面高指数(S-Go'/N-Me)、下颌平面角(MP/SN)均无显著改变(P>0.05)。结论:新型固定式Twin-block矫治器可显著促进下颌骨生长改建,有效进行垂直向控制,内收前牙同时改善患者侧貌,临床疗效可靠。 展开更多
关键词 固定式twin-block矫治器 骨性Ⅱ类错[牙合]畸形 功能矫治 垂直向控制
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改良Twin-block矫治器治疗骨性Ⅱ类下颌后缩患者颞下颌关节变化的三维分析研究 被引量:1
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作者 葛非凡 吴建华 +3 位作者 沈群 陈玉成 杭梦月 吴云芳 《皖南医学院学报》 2025年第5期458-462,共5页
目的:研究新型固定式改良Twin-block矫治器对青少年骨性Ⅱ类下颌后缩患者治疗前后颞下颌关节的三维变化。方法:从生长发育高峰期骨性Ⅱ类下颌后缩患者中随机选取20例为研究对象,均使用新型固定式改良Twin-block矫治器进行矫形治疗,矫治... 目的:研究新型固定式改良Twin-block矫治器对青少年骨性Ⅱ类下颌后缩患者治疗前后颞下颌关节的三维变化。方法:从生长发育高峰期骨性Ⅱ类下颌后缩患者中随机选取20例为研究对象,均使用新型固定式改良Twin-block矫治器进行矫形治疗,矫治前、后拍摄口腔颌面锥形束CT(CBCT),运用Mimics 21.0软件重建颞下颌关节的三维模型,在模型上测量并进行定量分析,再将治疗前后三维模型进行重叠配准,在颜色编码图上利用相同比例尺进行测量,可视化显示髁突的生长方向。结果:治疗后髁突高度、内外径和前后径均比治疗前增加(P<0.01);且髁突体积和表面积也均有增大(P<0.001);在颜色编码图中可见,髁突后上部颜色变化显著。结论:骨性Ⅱ类下颌后缩患者经新型固定式改良Twin-block矫治器治疗后,颞下颌关节内部分结构发生了适应性改建,髁突有明显向后上生长的趋势,在关节窝的相对位置也发生了前移。运用三维重建技术对该型矫治器治疗前后颞下颌关节进行定性定量分析,为临床应用提供了理论依据。 展开更多
关键词 改良twin-block矫治器 骨性Ⅱ类错牙合 颞下颌关节 髁突
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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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