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Mechanical Behavior and Failure Mechanism of an As-Extruded Mg-11wt%Y Alloy at Elevated Temperature

Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 969-981页

作者： Lan Zhang Dao-Kui Xu bao-jie Wang Cui-Lan Lu Shuo Wang Xiang-Bo Xu Dong-Liang Wang Xin Lv En-Hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangdong510070China

Through carrying out the high-temperature tensile experiments on an as-extruded Mg-11wt%Y alloy at 350℃,400℃,450℃,500℃and 550℃,the mechanical behavior and fracture mechanisms at elevated temperatures are investigated and *** results show that with the increase of temperature,the yield strength and ultimate tensile strength of the alloy increase at first and then decrease,while that the elongation ratio decreases firstly and then *** the sample being tested at 350℃,the values of yield strength,ultimate tensile strength and the elongation ratio are 188 MPa,266 MPa and 11%,*** 400℃,the yield strength and ultimate tensile strength reach the maximum values of,respectively,198 MPa and 277 MPa,but the elongation ratio is the lowest and its value is only 8%.When the applied temperature is increased to 550℃,the values of yield strength and ultimate tensile strength,respectively,decrease to 140 MPa and 192 MPa and the elongation ratio increases to 38%.Failure analysis demonstrates that the fracture surfaces of different samples are mainly composed of plastic dimples and exhibit the typical characteristic of ductile *** observation to the fracture side surfaces indicates that at the temperatures of 350℃and 400℃,microcracks mainly initiate in the interior of Mg_(24)Y_(5)*** the temperatures are 450℃,500℃and 550℃,the cracks preferentially initiate at the Mg_(24)Y_(5)/α-Mg interfaces.

关键词： Mg-Y alloy High-temperature tensile properties Fracture mechanism Failure analysis

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Two-dimensional bifunctional electrocatalyst(Mo-NiFe-LDH)with multilevel structure for highly efficient overall water splitting

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Rare Metals 2024年第6期43卷 2613-2622页

作者： bao-jie Zhang Bin Chang Shi-Peng Qiu Gang Zhao Xiao Wang Xi-Jin Xu Lan Mu Wen-Bo Liao Xiao-Jing Dong School of Physics and Technology University of JinanJinan 250000China KAUST Catalysis Center(KCC) King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdomof SaudiArabia School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China School of Physics and Physical Engineering Qufu Normal UniversityQufu273100China

To effectively address energy challenges,it is crucial to explore efficient and stable bifunctional nonprecious metal *** this study,a Mo-doped nickeliron layered double hydroxide with flower-cluster architecture was successfully prepared by a one-step hydrothermal method,which demonstrated a good water splitting *** an appropriate amount of Mo doping,some lattice distortions in the material provided reactive sites for the adsorption and conversion of intermediates,thus optimising the charge distribution of the ***,the multidimensional void structures formed after doping had a larger specific surface area and accelerated the penetration of the electrolyte,which significantly improved the activity of the catalyst in alkaline *** 10 mA·cm^(-2),the hydrogen and oxygen evolution overpotentials of Mo-doped nickel-iron double hydroxides(Mo-NiFe LDH/NF-0.2)were 167 and 220 mV,respectively,with an excellent durability up to 24 *** the Mo-NiFe LDH/NF-0,2 catalyst was used as the cathode and anode of an electrolytic cell,the catalyst achieved a current density of 10 mA·cm^(-2)at an applied voltage of 1.643 *** study provides a novel approach for designing excellent bifunctional electrocatalysts containing nonprecious metals.

关键词： Bifunctional electrocatalysts 2D multilevel structure Overall water splitting Mo-doped Ni-Fe LDH

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Establishment of acquired tracheoesophageal fistula using a modified magnetic compression technique in rabbits and its postmodeling evaluation

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1385-1394页

作者： Han Meng Fu-Yao Nan Na Kou Qin-Yan Hong Ming-Sheng Lv Ju-Bo Li bao-jie Zhang Hang Zou Lei Li Hong-Wu Wang Respiratory Disease Center Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100029China The First Clinical Medical College Beijing University of Chinese MedicineBeijing 100700China Department of Animal Experimental Center National Center for CardiovascularFuwai HospitalBeijing 100037China

BACKGROUND Previous studies have validated the efficacy of both magnetic compression and surgical techniques in creating rabbit tracheoesophageal fistula(TEF)*** compression achieves a 100%success rate but requires more time,while surgery,though less frequently successful,offers rapid model establishment and technical maturity in larger animal *** To determine the optimal approach for rabbit disease modeling and refine the *** TEF models were created in 12 rabbits using both the modified magnetic compression technique and *** of the time to model establishment,success rate,food and water intake,weight changes,activity levels,bronchoscopy findings,white blood cell counts,and biopsies were *** response to the failures encountered during modified magnetic compression modeling,we increased the sample size to 15 rabbit models and assessed the repeatability and stability of the models,comparing them with the original magnetic compression *** The modified magnetic compression technique achieved a 66.7%success rate,whereas the success rate of the surgery technique was 33.3%.Surviving surgical rabbits might not meet subsequent experimental requirements due to TEF-related *** the modified magnetic compression group,one rabbit died,possibly due to magnet corrosion,and another died from tracheal magnet *** events occurred during the second round of modified magnetic compression modeling,with one rabbit possibly succumbing to aggravated lung *** operation time of the first round of modified magnetic compression was 3.2±0.6 min,which was significantly reduced to 2.1±0.4 min in the second round,compared to both the first round and that of the original *** The modified magnetic compression technique exhibits lower stress responses,a simple procedure,a high success rate,and lower modeling costs,making it a more appropriate choice for constructing TEF models in

关键词： Tracheoesophageal fistula Modified magnetic compression technique Post-modeling evaluation Pneumonia Malnutrition

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两性纤维素多孔凝胶球的制备及其动态吸附性能

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纺织学报 2024年第5期45卷 102-112页

作者：郑康龚文丽鲍杰刘琳浙江理工大学材料科学与工程学院浙江杭州310018

用于废水处理的多孔凝胶球存在制备工艺繁琐,吸附种类单一,吸附效率低等不足;为提高多孔凝胶球的性能,采用滴入相分离、酯化反应引入羧基及希夫碱反应引入氨基的化学改性方法,制备得到兼具高孔隙率、高力学性能和羧基/氨基活性基团的两... 详细信息

用于废水处理的多孔凝胶球存在制备工艺繁琐,吸附种类单一,吸附效率低等不足;为提高多孔凝胶球的性能,采用滴入相分离、酯化反应引入羧基及希夫碱反应引入氨基的化学改性方法,制备得到兼具高孔隙率、高力学性能和羧基/氨基活性基团的两性纤维素多孔凝胶球(ACM),并构建动态吸附柱装置以探究不同条件下ACM对染料的动态吸附性能。结果表明:通过降低染料初始质量浓度,增加填料高度和减慢进液流速的方式可有效提高吸附柱的动态吸附效率;0.8 g的ACM可处理7.5 L含染料的废水;对ACM的动态吸附过程进行动态模型拟合,其与Thomas和Yoon-Nelson模型的拟合程度高,表明吸附是均匀表面的单分子层吸附,动态吸附过程中存在2个或多个速率控制步骤,内部扩散和外部扩散均不是吸附过程中的限速步骤。基于ACM优异的分级孔结构、丰富的活性位点和低传质阻力等优势,认为ACM展现出良好的动态吸附性能,在印染废水处理方面有较大应用潜力。

关键词：纤维素两性凝胶球吸附分离阴阳离子染料动态吸附性能印染废水废水处理

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Association between triglyceride-glucose index and colorectal polyps:A retrospective cross-sectional study

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World Journal of Gastrointestinal Endoscopy 2024年第2期16卷 55-63页

作者： Ya-jie Teng Ying-Xue Yang Jing-Jing Yang Qiu-Yan Lu Jia-Yi Shi Jian-Hao Xu jie bao Qing-Hua Wang Department of Gastroenterology The First People's Hospital of KunshanSuzhou 215300Jiangsu ProvinceChina Department of Pathology The First People's Hospital of KunshanSuzhou 215300Jiangsu ProvinceChina

BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses metabolic health and insulin resistance,and has been linked to gastrointestinal *** To investigate the potential association between the TyG index and CPs,as the relation between them has not been *** A total of 2537 persons undergoing a routine health physical examination and colonoscopy at The First People's Hospital of Kunshan,Jiangsu Province,China,between January 2020 and December 2022 were included in this retrospective cross-sectional *** excluding individuals who did not meet the eligibility criteria,descriptive statistics were used to compare characteristics between patients with and without *** regression analyses were conducted to determine the associations between the TyG index and the prevalence of *** TyG index was calculated using the following formula:Ln[triglyceride(mg/dL)×glucose(mg/dL)/2].The presence and types of CPs was determined based on data from colonoscopy reports and pathology *** A nonlinear relation between the TyG index and the prevalence of CPs was identified,and exhibited a curvilinear pattern with a cut-off point of 2.31.A significant association was observed before the turning point,with an odds ratio(95% confidence interval)of 1.70(1.40,2.06),P<***,the association between the TyG index and CPs was not significant after the cut-off point,with an odds ratio(95% confidence interval)of 0.57(0.27,1.23),P=*** Our study revealed a curvilinear association between the TyG index and CPs in Chinese individuals,suggesting its potential utility in developing colonoscopy screening strategies for preventing CRC.

关键词： Triglyceride-glucose index Colorectal polyps Colorectal cancer Insulin resistance Cross-sectional study

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Retraction note to:Association between triglyceride-glucose index and colorectal polyps:A retrospective cross-sectional study

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World Journal of Gastrointestinal Endoscopy 2024年第8期16卷 500-501页

We have decided to retract the above article because we have concluded that the limitations in our data sample may potentially lead to misinterpretation of the findings.

关键词： World Journal of Gastrointestinal Endoscopy Retraction note

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自适性语言测试题库CTT与IRT参数估计对比研究

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首都师范大学学报（社会科学版） 2024年第3期 180-189页

作者：修美丽柴省三鲍杰对外经济贸易大学国际学院北京语言大学国际学生教育政策与评价研究院

在计算机自适应性(CAT)与评价中,题库是测试系统实现的基础,其中题目参数估计质量是决定题库建设的核心和必要条件。研究以22582名中国汉语水平考试(HSK)考生的实测大数据为基础,采用分层随机抽样法,对获得的8个不同容量的被试样本进行... 详细信息

在计算机自适应性(CAT)与评价中,题库是测试系统实现的基础,其中题目参数估计质量是决定题库建设的核心和必要条件。研究以22582名中国汉语水平考试(HSK)考生的实测大数据为基础,采用分层随机抽样法,对获得的8个不同容量的被试样本进行了CTT和IRT参数的估计及比较研究。结果发现,在样本分布同质性前提下,当样本规模在500以内时,CTT与IRT的项目难度参数、区分度参数之间一致性较差;项目的区分度参数稳定性不高;考生能力参数之间存在显著相关性。在远程自适应性语言测试的题库建设中,建议采用大样本IRT参数估计方案。

关键词：计算机自适应性考试题库参数估计教育测量语言测试 CTT与IRT理论

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不同坐姿下的表面肌电特性及舒适度分析

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家具与室内装饰 2024年第5期31卷 93-97页

作者：鲍洁周立亚东华大学服装与艺术设计学院上海200051 现代服装设计与技术教育部重点实验室上海200051

为了解不同坐姿下人体主要工作肌群的活跃度与疲劳情况,让人们重视对坐姿的调整,并处于舒适健康的坐姿状态,邀请8名受试者对6种日常坐姿分别进行表面肌电测试,收集颈伸肌、竖脊肌、腹直肌与腹外斜肌的表面肌电信号以及不同身体部位与整... 详细信息

为了解不同坐姿下人体主要工作肌群的活跃度与疲劳情况,让人们重视对坐姿的调整,并处于舒适健康的坐姿状态,邀请8名受试者对6种日常坐姿分别进行表面肌电测试,收集颈伸肌、竖脊肌、腹直肌与腹外斜肌的表面肌电信号以及不同身体部位与整体主观舒适度评价。结果表明:坐姿舒适度为:靠背直立>后倾>直立>前倾>跷二郎腿>单边坐。其中靠背直立坐姿与后倾坐姿的肌肉活跃度与肌力水平较低,主观舒适度较高。因此,建议大众在工作和学习时保持靠背直立坐姿,在短暂放松休息时可采用后倾坐姿。同时,从肌力平衡角度,在日常生活中注重腹肌肌群的锻炼,可缓解腰部肌肉的发力,减少脊柱患病的风险。最后,在坐姿状态下,颈伸肌与竖脊肌对不适较为敏感,因此在座椅设计与坐具舒适性研究中应该优先考虑颈部与腰部的设计合理性与舒适情况。

关键词：表面肌电坐姿肌肉活跃度舒适度

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星载InSAR基线构型测量误差模型与灵敏度分析

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光学精密工程 2024年第1期32卷 33-42页

作者：鲍捷刘兴潭陈建武李林赵春晖北京控制工程研究所空间光电测量与感知实验室北京100190

为避免双天线InSAR系统基线测量动态监测过程中引入误差,影响基线测量精度,对基线长度与角度测量过程中的可能误差进行定性与定量分析。采用坐标变换法建立系统误差数学模型,明确测量系统的误差来源。提出误差灵敏度概念,对误差项进行... 详细信息

为避免双天线InSAR系统基线测量动态监测过程中引入误差,影响基线测量精度,对基线长度与角度测量过程中的可能误差进行定性与定量分析。采用坐标变换法建立系统误差数学模型,明确测量系统的误差来源。提出误差灵敏度概念,对误差项进行定量计算,并对每一自由度的误差源进行灵敏度分析,进一步形成综合误差定量合成结果。根据误差灵敏度系数给出一组精度反演误差分配案例。最后,依据蒙特卡洛法在MATLAB平台闭环验证精度量化分配方法的可行性与稳定性。仿真分析结果表明,激光视觉三轴位置的测量精度要求为300μm(3σ),三轴角度的测量精度要求为50″(3σ),即可满足基线长度精度1 mm(1.6σ),基线角度精度2″(1.6σ)。通过本方法可由测量环境条件输入直接获得基线测量的精度,根据灵敏度系数对误差分配进行反演可以得到系统最优布局,其结果可为测量系统的方案设计与精度分解提供有效指导。

关键词：干涉合成孔径雷达基线测量误差模型灵敏度分析

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Ensemble Attention Guided Multi-SEANet Trained with Curriculum Learning for Noninvasive Prediction of Gleason Grade Groups from MRI

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Journal of Shanghai Jiaotong university(Science) 2024年第1期29卷 109-119页

作者：沈傲胡冀苏金鹏飞周志勇钱旭升郑毅包婕王希明戴亚康 School of Computer Science and Technology Changchun University of Science and TechnologyChangchun 130022China Suzhou Institute of Biomedical Engineering and Technology Chinese Academy of SciencesSuzhou 215163JiangsuChina School of Biomedical Engineering(SooChow) University of Science and Technology of ChinaSuzhou 215163JiangsuChina Department of Radiology The First Afiliated Hospital of Soochow UniversitySuzhou 215006JiangsuChina

The Gleason grade group(GG)is an important basis for assessing the malignancy of prostate can-cer,but it requires invasive biopsy to obtain *** noninvasively evaluate GG,an automatic prediction method is proposed based on multi-scale convolutional neural network of the ensemble attention module trained with curriculum ***,a lesion-attention map based on the image of the region of interest is proposed in combination with the bottleneck attention module to make the network more focus on the lesion ***,the feature pyramid network is combined to make the network better learn the multi-scale information of the lesion ***,in the network training,a curriculum based on the consistency gap between the visual evaluation and the pathological grade is proposed,which further improves the prediction performance of the ***-perimental results show that the proposed method is better than the traditional network model in predicting GG *** quadratic weighted Kappa is 0.4711 and the positive predictive value for predicting clinically significant cancer is 0.9369.

关键词： prostate cancer Gleason grade groups(GGs) bi-parametric magnetic resonance imaging deep learn-ing curriculum learning

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