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On the superplastic deformation mechanisms of near-αTNW700 titanium alloy

Journal of Materials Science & Technology 2022年第13期108卷 173-185页

作者： Lixia Ma Min Wan Weidong Li Jie Shao xiaoning han Jichun Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China AVIC Manufacturing Technology Institute Beijing 100024China

The new near-αTNW700 titanium alloy is a potential candidate material for high performance ultrasonic/hypersonic aircrafts,which is designed for short-term service at 700℃.This study systematically investigated the superplastic deformation microstructure evolution and mechanism of TNW700 alloy at different strain rates and true strains at 925℃.Results show that TNW700 alloy exhibits excellent superplastic behavior in a constant strain rate range of 0.0005-0.005 s^(-1) with elongation above 400%.The peak stress decreases with decreasing strain rate,which is related to the increase ofβ-phase volume fraction caused by the increase of thermal exposure *** addition,significant strain hardening is observed in early-middle stage of superplastic deformation,and flow softening is followed in middle-late *** rationalize these complex flow behaviors,electron backscatter diffraction(EBSD)and high resolution transmission electron microscopy(HRTEM)were used to characterize the *** hardening is correlated to the synergistic effect ofβgrain growth,dislocation accumulation,silicide precipitate,and solid solution strengthening ofα*** dynamic recrystallization(CDRX)induced the fragmentation of primaryαgrains in middle-late stage of superplastic deformation,and the refinement ofαgrains,the increase ofβphase volume fraction and dynamic dislocation recovery are main causes of high strain *** addition,EBSD and TEM observations confirmed texture randomization,fine equiaxed primaryαgrains and intragranular dislocation movement,indicating that grain boundary sliding(GBS)accommodated by dislocation sliding/climb is the dominant superplastic deformation mechanism of TNW700 alloy.

关键词： Near-αtitanium alloy Superplastic deformation Strain hardening and flow softening Microstructure evolution Deformation mechanisms

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Synthesis and characterization of high density and high aspect ratio Ag_2S nanoparticle nanowires from a paired cell method

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Chinese Science Bulletin 2011年第17期56卷 1828-1831页

作者： LI xiaoning YANG XiuChun han ShanShan LU Wei HOU JunWei LIU Yan School of Materials Science and Engineering Tongji University Shanghai 200092 China

Ag_2S nanoparticle nanowires were prepared in a porous anodic aluminum oxide template by a simple paired cell method,and were characterized by XRD,FESEM,HRTEM and *** results showed that the as-prepared nanowires were composed of monoclinic Ag_2S *** nanowire diameters ranged from 165 to 270 nm,and Ag_2S nanoparticles were nearly spherical with diameters of 40 to 60 *** paired cell method is simple,low cost and easy to control for the fabrication of high density and high aspect ratio Ag_2S nanoparticle nanowires.A formation mechanism for the nanoparticle nanowires was suggested.

关键词：纳米粒子纳米线高宽比高密度细胞配对多孔阳极氧化铝 Ag2S

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Comparison of general practice residents’ attitudes and perceptions about training in two programmes in China: a mixed methods survey

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Family Medicine and Community Health 2019年第4期7卷 64-73页

作者： Siqing Lian Yu Xia Jinzhi Zhang xiaoning han Chunhua Chi Michael D Fetters General Practice Department Peking University First HospitalPekingXicheng DistrictChina General Practice Department Peking University Shenzhen HospitalShenzhenGuangdongChina Cardiology Department Peking University First HospitalPekingXicheng DistrictChina Department of General Practice Peking University First HospitalPekingXicheng DistrictChina Department of Family Medicine University of MichiganAnn ArborMichiganUSA

Objective To understand general practice(GP)residents’attitudes about their residency training in *** Mixed methods survey administered *** Two GP training programmes similar in most regards according to current GP training policy of 5 years’undergraduate degree in medicine and 3 years of postgraduate GP residency training-but differing as the Beijing programme has adopted educational innovations beyond the nationally prescribed standard curriculum used by the second Shenzhen *** 105(85%)of eligible GP trainees,35(90%)in the innovative Beijing programme and 70(83%)in the standard training Shenzhen *** Overall,residents felt discrimination because of specialty choice,and that they lacked competency as a general *** residents commented faculty had negative teaching *** residents were more satisfied than Shenzhen residents with their training(p=0.001),and felt teaching faculty had sufficient knowledge(phance training and promote positivity about job *** findings imply that GP residents in China face many training challenges that are similar to other international reports,while also implicating benefits of using an innovative curricular approach.

关键词： programme attitude faculty

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飞机钣金零件多态模型几何信息定义方法

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西北工业大学学报 2007年第2期25卷 239-244页

作者：王俊彪韩晓宁刘闯西北工业大学机电学院陕西西安710072

飞机钣金零件成形工件几何信息的定义是其数字化设计与制造的桥梁。文中提出了多态模型几何信息定义流程,采用基于树的数据结构和XML表达方式,建立了钣金零件几何信息模型。对于成形件态,提出了典型钣金零件结构要素设计方法;对于毛坯... 详细信息

飞机钣金零件成形工件几何信息的定义是其数字化设计与制造的桥梁。文中提出了多态模型几何信息定义流程,采用基于树的数据结构和XML表达方式,建立了钣金零件几何信息模型。对于成形件态,提出了典型钣金零件结构要素设计方法;对于毛坯态和中间件态,提出了基于结构要素的展开算法。基于上述方法开发了多态模型几何信息定义系统,并应用于L15飞机框肋类零件制造,结合实例说明了应用过程。应用表明,该方法提高了钣金零件成形质量,降低了制造成本。

关键词：几何信息 XML 多态模型飞机钣金零件

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Current situation,efficacy,and safety of extracorporeal cardiopulmonary resuscitation in China

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Chinese Medical Journal 2022年第23期135卷 2878-2879页

作者： Ying Liu xiaoning han Qi Qi Zhiyong Yuan Fuhua Wang Kai Song Xiaotong Hou Jinyan Xing Department of Critical Care Medicine The Affiliated Hospital of Qingdao UniversityQingdaoShandong 266000China School of Mathematics and Statistics Qingdao UniversityQingdaoShandong 266000China Center for Cardiac Intensive Care Beijing Anzhen HospitalCapital Medical UniversityChaoyang DistrictBeijing 100029China

To the Editor:The survival rate from conventional cardiopulmonary resuscitation(CCPR)of out-of-hospital and in-hospital cardiac arrest ranges from 9%to 20%.[1]Without returning of spontaneous circulation(ROSC)after CCPR,the chance of recovery is very *** venoarterial extracorporeal membrane oxygenation in those patients may provide adequate organ perfusion that allows for longer organ viability and permit time for therapies seeking to correct the inciting pathologic event,which is termed extracorporeal cardiopulmonary resuscitation(ECPR).[2]Time to treatment,ECPR-related complications,as well as etiology,have been recognized as the main predictors of survival for ECPR patients.[3]ECPR has been carried out more and more in China,but the information on ECPR application remains ***,we conducted a retrospective survey about the usage of ECPR in China,including patient selection,initiation and management of extracorporeal mechanical ventilation(ECMO),patient outcome,and compared the status during 2017 and 2020.

关键词： seeking situation usage

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内容依赖:作为媒体的微信使用与满足研究

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国际新闻界 2014年第4期36卷 82-96页

作者：韩晓宁王军张晗中国人民大学新闻与社会发展研究中心中国人民大学新闻学院

本文基于使用与满足理论、媒介系统依赖视角进行量化分析,考察受众对微信媒体功能的使用行为、接触动机和满足情况。研究发现受众对微信媒体功能的使用动机可以归纳为信息获取、社会交往和功能性体验三个取向。受众对内容类型的接触偏... 详细信息

本文基于使用与满足理论、媒介系统依赖视角进行量化分析,考察受众对微信媒体功能的使用行为、接触动机和满足情况。研究发现受众对微信媒体功能的使用动机可以归纳为信息获取、社会交往和功能性体验三个取向。受众对内容类型的接触偏好与上述三种动机一起对微信媒体使用满足具有显著影响;女性的微信媒体使用满足更高。这一媒介接触模式体现出受众媒体使用的内容依赖特征;微信用户通过在微信平台阅读新闻与评论信息,来提升自己对微信媒体的使用满足。

关键词：微信媒介依赖公众订阅号使用偏好

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坚定与动摇：新闻从业者的职业承诺及其影响因素研究

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国际新闻界 2020年第8期42卷 66-87页

作者：王军韩晓宁重庆大学新闻学院中国人民大学新闻学院中国人民大学新闻与社会发展研究中心

本研究对全国范围内396名新闻从业者进行问卷调查,考察其职业承诺状况。职业承诺可划分为情感承诺、继续承诺和规范承诺等三个维度,研究发现该群体职业承诺状况整体处于中等水平,情感承诺和规范承诺表现较低、继续承诺表现较好。从业体... 详细信息

本研究对全国范围内396名新闻从业者进行问卷调查,考察其职业承诺状况。职业承诺可划分为情感承诺、继续承诺和规范承诺等三个维度,研究发现该群体职业承诺状况整体处于中等水平,情感承诺和规范承诺表现较低、继续承诺表现较好。从业体验、职业志向危机和职业期望价值等三类因素对新闻从业者的职业承诺水平产生影响:从业体验层面,接受新闻教育年限和工作满意度具有显著的正面促进作用;职业志向危机层面,当从业者感知舆论监督功能和社会关怀面向存在理想与现实差异时,则职业承诺较低;职业期望价值层面,职业效能感知中的音视频技能因素与职业价值感知中的保健因素、声望地位因素和发展因素对职业承诺水平具有显著正面作用,而外部机会感知则具有负面影响。从业体验和职业志向危机对职业承诺的影响不仅具有直接效应,还可通过影响职业期望价值来产生间接效应。

关键词：新闻从业者职业承诺情感承诺继续承诺规范承诺

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