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浇覆温度对铝/钢复合板界面及性能的影响

稀有金属 2024年第4期48卷 487-497页

作者：李超李元东邱谨罗晓梅周宏伟兰州理工大学材料科学与工程学院甘肃兰州730050 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室甘肃兰州730050 兰州理工大学有色金属合金及加工教育部重点实验室甘肃兰州730050

选用6061铝合金和Q235钢板,采用铸轧工艺技术制备铝/钢双金属复合板,研究6061铝合金不同浇覆温度对铝/钢复合板界面组织以及力学性能的影响。使用光学显微镜(OM)和场发射扫描电子显微镜(SEM)观察复合板界面显微组织形貌,通过能谱仪(EDS)... 详细信息

选用6061铝合金和Q235钢板,采用铸轧工艺技术制备铝/钢双金属复合板,研究6061铝合金不同浇覆温度对铝/钢复合板界面组织以及力学性能的影响。使用光学显微镜(OM)和场发射扫描电子显微镜(SEM)观察复合板界面显微组织形貌,通过能谱仪(EDS)和X射线衍射仪(XRD)进行微区成分分析及分析界面金属间化合物,使用显微硬度仪测量界面附近硬度变化情况,并且对复合板力学性能进行测试。结果表明,随着浇覆温度从650℃升高到730℃,铝/钢复合板界面扩散层厚度逐渐变厚且均匀,界面处形成Al5Fe_(2)和Al_(3)Fe等金属间化合物;当浇覆温度为730℃时,扩散层厚度最厚为5.9μm,界面处显微硬度最高,达到HV 120。抗拉强度和剪切强度随着浇覆温度升高先提高后降低,当浇覆温度为710℃时,复合板的力学性能最好,复合板铝钢厚度比为2∶1,抗拉强度为233 MPa,相比较铸轧态6061铝合金,抗拉强度提高了66.4%,断裂延伸率为25.5%,剪切强度为92.5 MPa,剪切断裂发生在6061铝合金一侧。

关键词：铝/钢复合板浇覆温度铸轧金属间化合物力学性能

Spindle cell carcinoma of the mandible:a case report

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The Journal of Biomedical Research 2017年第3期31卷 273-276页

作者： Long Xie Heming Wu Siyu liu hongwei li Institute of Stomatology Nanjing Medical University Department of Oral and Maxillofacial Surgery Stomatological Hospital of Nanjing Medical University

Spindle cell carcinoma is a rare highly malignant squamous cell carcinoma.Here,we describe a case of a 74-yearold Chinese female who presented with a 2-week history of pain and swelling in the left retromolar region.Surgical resection and titanium plate prosthesis were performed and histological analysis revealed spindle squamous cell carcinoma.

关键词： mandible sarcomatoid carcinoma spindle squamous cell carcinoma prognosis treatment

Network prediction of surgical complication clusters:a prospective multicenter cohort study

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Science China(life Sciences) 2023年第7期66卷 1636-1646页

作者： Xiaochu Yu Peng Wu Zixing Wang Wei Han Yuguang Huang Shijie Xin Qiang Zhang Shengxiu Zhao Hong Sun Guanghua Lei Taiping Zhang Luwen Zhang Yubing Shen Wentao Gu hongwei li Jingmei Jiang Peking Union Medical College Hospital Chinese Academy of Medical SciencesBeijing100730China Institute of Basic Medical Sciences Chinese Academy of Medical Sciences/School of Basic MedicinePeking Union Medical CollegeBeijing100005China The First Hospital of China Medical University Shenyang110001China Qinghai Provincial People’s Hospital Xining810007China Xiangya Hospital of Central South University Changsha410008China Research Department PaodingAIBeijing100083China

Complicated relationships exist in both occurrence and progression of surgical complications,which are difficult to account for using a separate quantitative method such as prediction or grading.Data of 51,030 surgical inpatients were collected from four academic/teaching hospitals in a prospective cohort study in China.The relationship between preoperative factors,22 common complications,and death was analyzed.With input from 54 senior clinicians and following a Bayesian network approach,a complication grading,cluster-visualization,and prediction(GCP)system was designed to model pathways between grades of complication and preoperative risk factor clusters.In the GCP system,there were 11 nodes representing six grades of complication and five preoperative risk factor clusters,and 32 arcs representing a direct association.Several critical targets were pinpointed on the pathway.Malnourished status was a fundamental cause widely associated(7/32 arcs)with other risk factor clusters and complications.American Society of Anesthesiologists(ASA)score≥3 was directly dependent on all other risk factor clusters and influenced all severe complications.Grade III complications(mainly pneumonia)were directly dependent on4/5 risk factor clusters and affected all other grades of complication.Irrespective of grade,complication occurrence was more likely to increase the risk of other grades of complication than risk factor clusters.

关键词： surgical complication network system complication grading complication prediction complication management

Analysis of anisotropy mechanism in the mechanical property of titanium alloy tube formed through hot flow forming

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Journal of Materials Science & Technology 2021年第27期86卷 77-90页

作者： Zhenni Lei Pengfei Gao Xianxian Wang Mei Zhan hongwei li State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of High-Performance Precision Forming Technology and EquipmentSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an710072China College of Mechanical&Electrical Engineering Shaanxi University of Science&TechnologyXi’an710021China

Anisotropy of mechanical property is an important feature influencing the service performance of titanium(Ti)alloy tube component.In this work,it is found that the hot flow formed Ti alloy tube exhibits higher yield strength along circumferential direction(CD),and larger elongation along rolling direction(RD),presenting significant anisotropy.Subsequently,the quantitative characteristics and underlying mechanism of the property anisotropy were revealed by analyzing the slip,damage and fracture behavior under the combined effects of the spun{0002}basal texture and fibrous microstructure for different loading directions.The results showed that the prismatic slip in primaryαgrain is the dominant deformation mechanism for both loading directions at the yielding stage.The prismatic slip is harder under CD loading,which makes CD loading present higher yield strength than RD loading.Additionally,the yield anisotropy can be quantified through the inverse ratio of the averaged Schmid Factor of the activated prismatic slip under different loading directions.As for the plasticity anisotropy,the harder and slower slip development under CD loading causes that the CD loading presents larger external force and normal stress on slip plane,thus leading to more significant cleavage fracture than RD loading.Moreover,the micro-crack path under RD loading is more tortuous than CD loading because the fibrous microstructure is elongated along RD,which may suppress the macro fracture under RD loading.These results suggest that weakening the texture and fibrous morphology of microstructure is critical to reduce the differences in slip,damage and fracture behavior along different directions,alleviate the property anisotropy and optimize the service performance of Ti alloy tube formed by hot flow forming.

关键词： Titanium alloy tube Hot flow forming Mechanical property anisotropy Slip behavior Damage evolution

Cytogenetic identification and molecular marker development for the novel stripe rust-resistant wheat- Thinopyrum intermedium translocation line WTT11

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aBIOTECH 2021年第4期2卷 343-356页

作者： Guotang Yang Qi Zheng Pan Hu hongwei li Qiaoling Luo Bin li Zhensheng li State Key Laboratory of Plant Cell and Chromosome Enginering Institute of Genetics and Developmental Biology The Innovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Stripe rust,caused by Puccinia striformis f.***.tritici(Pst),is one of the most destructive diseases of wheat(Triticum aestivum L)worldwide.Xiaoyan 78829,a partial amphidiploid developed by crossing common wheat with Thinopyrum intermedium,is immune to wheat stripe rust.To transfer the resis-tance gene of this excellent germplasm resource to wheat,the tr anslocation line WTT11 was produced by pollen irradiation and assessed for immunity to stripe rust races CYR32,CYR33 and CYR34.A novel stripe rust-resistance locus derived from Th.intermedium was confirmed by linkage and diagnostic marker analyses.Molecular cytogenetic analyses revealed that WTT11 carries a TTh 2DL translocation.The breakpoint of 1B was located at 95.5 MB,and the alien segments were found to be homoeologous to wheat-group chromosomes 6 and 7 according to a wheat660K single-nucleotide polymorphism(SNP)array analysis.Ten previously developed PCR-based markers were confirmed to rapidly trace the alien segments of WTT11,and 20 kompetitive allele-specific PCR(KASP)markers were developed to enable genotyping of Th.intermedium and common wheat.Evaluation of agronomic traits in two consecutive crop seasons uncovered some favorable agronomic traits in WTT11,such as lower plant height and longer main panicles,that may be applicable to wheat improvement.As a novel genetic resource,the new resistance locus may be useful for wheat disease-resistance breeding.

关键词： Wheat-Thinopyrum intermedium translocation line CYR34 Cytogenetic analyses Wheat660k SNP array PCR-based markers KASP markers

Numerical Solution of Blow-Up Problems for NonlinearWave Equations on Unbounded Domains

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Communications in Computational Physics 2013年第8期14卷 574-598页

作者： Hermann Brunner hongwei li Xiaonan Wu Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong Kong Department of Mathematics and Statistics Memorial University of NewfoundlandSt.John’sNLA1C 5S7Canada College of Mathematical Sciences Shandong Normal UniversityJinan250014P.R.China.

The numerical solution of blow-up problems for nonlinear wave equations on unbounded spatial domains is considered.Applying the unified approach,which is based on the operator splitting method,we construct the efficient nonlinear local absorbing boundary conditions for the nonlinear wave equation,and reduce the nonlinear problem on the unbounded spatial domain to an initial-boundary-value problem on a bounded domain.Then the finite difference method is used to solve the reduced problem on the bounded computational domain.Finally,a broad range of numerical examples are given to demonstrate the effectiveness and accuracy of our method,and some interesting propagation and behaviors of the blow-up problems for nonlinear wave equations are observed.

关键词： Finite-time blow-up nonlinear wave equation absorbing boundary conditions finite differencemethod unbounded domains

面向SAR图像目标分类的CNN模型可视化方法

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雷达学报（中英文） 2024年第2期13卷 359-373页

作者：李妙歌陈渤王东升刘宏伟西安电子科技大学雷达信号处理全国重点实验室西安710071

卷积神经网络(CNN)在合成孔径雷达(SAR)图像目标分类任务中应用广泛。由于网络工作机理不透明,CNN模型难以满足高可靠性实际应用的要求。类激活映射方法常用于可视化CNN模型的决策区域,但现有方法主要基于通道级或空间级类激活权重,且在... 详细信息

卷积神经网络(CNN)在合成孔径雷达(SAR)图像目标分类任务中应用广泛。由于网络工作机理不透明,CNN模型难以满足高可靠性实际应用的要求。类激活映射方法常用于可视化CNN模型的决策区域,但现有方法主要基于通道级或空间级类激活权重,且在SAR图像数据集上的应用仍处于起步阶段。基于此,该文从神经元特征提取能力和网络决策依据两个层面出发,提出了一种面向SAR图像的CNN模型可视化方法。首先,基于神经元的激活值,对神经元在其感受野范围内的目标结构学习能力进行可视化,然后提出一种通道-空间混合的类激活映射方法,通过对SAR图像中的重要区域进行定位,为模型的决策过程提供依据。实验结果表明,该方法给出了模型在不同设置下的可解释性分析,有效拓展了卷积神经网络在SAR图像上的可视化应用。

关键词：合成孔径雷达可视化分析卷积神经网络类激活映射神经元

汉防己甲素通过抑制Mincle/Syk信号介导的巨噬细胞炎性活化减轻小鼠缺血再灌注诱导的急性肾损伤

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中国病理生理杂志 2024年第4期40卷 670-678页

作者：彭泽王洪连粟宏伟王丽成都市双流区九江社区卫生服务中心四川成都610000 西南医科大学附属中医医院中西医结合研究中心四川泸州646000 西南医科大学附属中医医院泌尿外科四川泸州646000

目的:探讨汉防己甲素(Tet)对小鼠缺血再灌注诱导的急性肾损伤(IRI-AKI)的作用及其机制。方法:8周龄雄性C57BL/6小鼠随机分为假手术组、IRI-AKI组、低剂量(20 mg/kg)Tet组、高剂量(40 mg/kg)Tet组和槲皮素(50 mg/kg)阳性对照组,每组6只... 详细信息

目的:探讨汉防己甲素(Tet)对小鼠缺血再灌注诱导的急性肾损伤(IRI-AKI)的作用及其机制。方法:8周龄雄性C57BL/6小鼠随机分为假手术组、IRI-AKI组、低剂量(20 mg/kg)Tet组、高剂量(40 mg/kg)Tet组和槲皮素(50 mg/kg)阳性对照组,每组6只。采用双侧肾动静脉夹闭45 min后恢复血供的方法建立IRI-AKI模型,Tet和槲皮素组的IRI-AKI小鼠于术前1 h及术后连续3 d给予相应剂量药物腹腔注射,假手术和IRI-AKI组小鼠给予同等体积溶剂注射。实验终点处死动物,收集血清及肾脏组织样本,进行肾功能、病理、mRNA及蛋白等指标检测。在体外,采用脂多糖(LPS;300μg/L)刺激的原代小鼠骨髓来源巨噬细胞(BMDM)进行Tet(1、2和4 mg/L)的抗炎活性研究。结果:(1)与IRI-AKI组相比,低和高剂量Tet干预均能显著降低血清肌酐和血尿素氮水平(P<0.05),并减轻肾小管病理损伤(P<0.05)。(2)Tet干预可以显著抑制IRI-AKI小鼠肾组织中白细胞介素1β(IL-1β)和IL-6的mRNA和蛋白表达及NF-κB信号的活化,减少肾组织巨噬细胞浸润(P<0.05)。(3)在LPS刺激的BMDM中,Tet同样抑制IL-1β和IL-6的mRNA和蛋白表达及NF-κB信号的活化(P<0.05)。(4)进一步实验显示,Tet可以显著降低LPS刺激的BMDM和IRI-AKI小鼠肾组织中Mincle、Syk和p-Syk的表达水平(P<0.05)。结论:Tet可以显著减轻IRI-AKI小鼠肾损伤,减轻肾组织炎症反应,其可能的机制为抑制巨噬细胞Mincle/Syk/NF-κB促炎信号通路。

关键词：汉防己甲素急性肾损伤缺血再灌注巨噬细胞 Mincle/Syk/NF-κB信号通路

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方形通道内超临界压力二氧化碳传热恶化数值研究

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北京航空航天大学学报 2024年第6期50卷 1888-1897页

作者：王彦红李雨健李洪伟东明东北电力大学能源与动力工程学院吉林132012 大连理工大学能源与动力学院大连116024

基于二氧化碳代替碳氢燃料进行航空发动机热防护的应用,开展方形冷却通道内超临界二氧化碳传热恶化数值研究。探究沿通道轴向和周向的换热特征,通过温度、局部流量、流线的分布情况揭示传热恶化的原因,进一步通过边界层分析阐述传热恶... 详细信息

基于二氧化碳代替碳氢燃料进行航空发动机热防护的应用,开展方形冷却通道内超临界二氧化碳传热恶化数值研究。探究沿通道轴向和周向的换热特征,通过温度、局部流量、流线的分布情况揭示传热恶化的原因,进一步通过边界层分析阐述传热恶化的演变过程。考察运行压力和壁面粗糙度对换热的影响机制。获得不同运行压力和壁面粗糙度下的传热恶化临界热流密度,建立临界热流密度预测准则。结果表明:通道顶部壁面附近高温类气态层、局部流量减小和流线畸变是传热恶化的特征,缓冲层出现湍动能剧减和流速峰值是传热恶化的原因。提高运行压力和增大壁面粗糙度有利于抑制传热恶化问题,所建准则(误差±15%)可实现对传热恶化临界热流密度的良好预测。

关键词：方形通道超临界压力二氧化碳传热恶化边界层