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Shakedown Criterion Employing Actual Residual Stress Field and Its Application in Numerical Shakedown Analysis

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 919-927页

作者： ZOU Zongyuan GUO Baofeng li Yinxiao JIN Miao ZHAO shiyan Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Chinese 91315 People's liberation Army Troops

Construction of the static admissible residual stress field and searching the optimal field are key tasks in the shakedown analysis methods applying the static theorem. These methods always meet dimension obstacles when dealing with complex problems. In this paper, a novel shakedown criterion is proposed employing actual residual stress field based on the static shakedown theorem. The actual residual stress field used here is produced under a specified load path, which is a sequence of proportional loading and unloading from zero to all the vertices of the given load domain. This ensures that the shakedown behavior in the whole load domain can be determined based on the theorem proposed by K6nig. The shakedown criterion is then implemented in numerical shakedown analysis, The actual residual stress fields are calculated by incremental finite element elastic-plastic analysis technique for finite deformation under the specified load path with different load levels. The shakedown behavior and the shakedown limit load are determined according to the proposed criterion. The validation of the criterion is performed by a benchmark shakedown example, which is a square plate with a central hole under biaxial loading. The results are consistent with existing results in the literatures and are validated by full cyclic elastic-plastic finite element analysis. The numerical shakedown analysis applying the proposed criterion avoids processing dimension obstacles and performing full cyclic elastic-plastic analysis under arbitrary load paths which should be accounted for appearing. The effect of material model and geometric changes on shakedown behavior can he considered conveniently.

关键词： elastoplastic finite element shakedown criterion specified load path actual residual stress field

国际金融危机对梧州经济金融的冲击及对策建议

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区域金融研究 2009年第6期 43-45页

作者：李世炎黄绍进区永纯李菲江鸿谢映华莫丹中国人民银行梧州市中心支行广西梧州543002

本课题调研小组深入调查分析国际金融危机给广西梧州市经济金融带来的冲击,在此基础上研究提出应对措施,旨在推动地方经济尽快走出金融危机的阴影,促进经济金融和谐健康发展。

关键词：金融危机冲击经济金融对策

Synergistic Effect of Metal Doping and Tethered ligand Promoted High-Selectivity Conversion of CO_(2)to C_(2)Oxygenates at Ultra-Low Potential

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Energy & Environmental Materials 2022年第3期5卷 892-898页

作者： Xiaowan Bai li Shi Qiang li Chongyi ling Yixin Ouyang shiyan Wang Jinlan Wang School of Physics Southeast UniversityNanjing 211189China

Effectively controlling the selectivity of C_(2) oxygenates is desirable for electrocatalytic CO_(2) *** catalyst has been considered as the most potential for reducing CO_(2) to C_(2) products,but it still suffers from low C_(2) selectivity,high overpotential,and competitive hydrogen evolution reaction(HER).Here,we propose a design strategy to introduce a second metal that weakly binds to H and a functional ligand that provides hydrogen bonds and protons to achieve high selectivity of C_(2)oxygenates and effective suppression of HER on the Cu(100)surface *** metals and eleven ligands are screened using first-principles calculations,which shows that Sn is the most efficient for inhibiting HER and cysteamine(CYS)ligand is the most significant in reducing the limiting potential of^(*)CO hydrogenation to^(*)*** the post C-C coupling steps,a so-called“pulling effect”that transfers H in the CYS ligand as a viable proton donor to the C_(2)intermediate to form an H bond,can further stabilize the OH group and facilitate the selection of C_(2)products toward ***,this heterogeneous electrocatalyst can effectively reduce CO_(2)to ethanol and ethylene glycol with an ultra-low limiting potential of-0.43 *** study provides a new strategy for effectively improving the selectivity of C_(2)oxygenates and inhibiting HER to achieve advanced electrocatalytic CO_(2)reduction.

关键词： metal doping hydrogen-bonding ligand density functional theory electrochemical CO_(2)reduction C_(2)oxygenates selectivity

超高压碳化硅N沟道IGBT器件的设计与制造

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电子与封装 2022年第4期22卷 10-15页

作者：杨晓磊李士颜赵志飞李赟黄润华柏松南京电子器件研究所宽禁带半导体电力电子器件国家重点实验室南京210016

自主设计和制备了一种耐压超过20 kV的超高压碳化硅(SiC)N沟道绝缘栅双极晶体管(Insulated Gate Bipolar Transistor,IGBT)器件。通过仿真设计优化了器件结构,同时结合自支撑衬底剥离技术、背面激光退火技术以及载流子寿命提升技术,成功... 详细信息

自主设计和制备了一种耐压超过20 kV的超高压碳化硅(SiC)N沟道绝缘栅双极晶体管(Insulated Gate Bipolar Transistor,IGBT)器件。通过仿真设计优化了器件结构,同时结合自支撑衬底剥离技术、背面激光退火技术以及载流子寿命提升技术,成功在N型SiC衬底上制备了SiC N沟道IGBT器件。测试结果表明,该器件阻断电压为20.08 kV时,漏电流为50μA。当栅电极施加20 V电压,集电极电流为20 A时,器件的导通电压为6.0 V,此时器件的微分比导通电阻为27 mΩ·m^(2)。该值仅为15 kV SiC金属氧化物半导体场效应晶体管(Metal-Oxide-Semiconductor Field-Effect Transistor,MOSFET)比导通电阻的1/7,充分显示出SiC N沟道IGBT器件作为双极型器件在高阻断电压、高导通电流密度等方面的突出优势。

关键词：碳化硅 N沟道IGBT 超高压载流子寿命提升技术

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半干面加工工艺论述

粮食加工 2022年第1期47卷 34-36页

作者：张培刘羽泽王崇李鸿印张蓬子李世岩高健中国农业机械化科学研究院北京100083 中国包装和食品机械有限公司北京100083 冰河冷媒科技(北京)有限公司北京100027

通过对半干面特性和加工现状分析,阐述2种国内半干面加工工艺及其优缺点,以及半干面加工机械化、自动化现状及存在问题,为半干面产业创新发展提供支撑。

关键词：半干面加工工艺自动化连续化

CGF复合丝素蛋白-羟基磷灰石支架对兔下颌骨缺损的修复作用

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河北医学 2020年第4期26卷 698-702页

作者：陈琦李石岩禹鑫曹雷郝旭峰王承阳河北省承德市中心医院口腔科河北承德067000

目的:探索浓缩生长因子(CGF)复合丝素蛋白-羟基磷灰石支架在促进兔下颌骨缺损修复作用的作用。方法:取健康新西兰大白兔48只随机分为三组,每组16只,并于同期制备右侧下颌骨骨缺损模型。其中A组为复合材料组,B组为单纯羟基磷灰石组,C组... 详细信息

目的:探索浓缩生长因子(CGF)复合丝素蛋白-羟基磷灰石支架在促进兔下颌骨缺损修复作用的作用。方法:取健康新西兰大白兔48只随机分为三组,每组16只,并于同期制备右侧下颌骨骨缺损模型。其中A组为复合材料组,B组为单纯羟基磷灰石组,C组为空白组。所有动物分别于2、4、8、12周处死取材并制备组织标本,并行大体观察、影像学及组织学分析检测,收集影像学分析值加以评价,对分析结果行SPSS17.0分析,P<0.05有统计学意义。结果:通过大体观察、影像学分析显示A组新生骨情况、成骨速度明显优于其他两组,并通过骨密度分析及新生骨面积测算也显示了复合材料在促进成骨的优越性。结论:浓缩生长因子(CGF)复合丝素蛋白-羟基磷灰石支架在促进颌骨缺损的实验中显示出良好的成骨作用,具有明显的骨诱导作用,可望成为临床中修复骨缺损的新型材料。

关键词：浓缩生长因子CGF 羟基磷灰石复合组织工程材料下颌骨缺损

Defect repairing in two-dimensional transition metal dichalcogenides

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Frontiers of physics 2023年第5期18卷 47-64页

作者： shiyan Zeng Fang li Chao Tan Lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Atomically thin two-dimensional(2D)transition metal dichalcogenides(TMDCs)have stimulated enormous research interest due to rich phase structure,high theoretical carrier mobility and layer-dependent *** view of the close correlation between defects and properties in 2D TMDCs,more attentions have been paid on the defect engineering in recent years,however the mechanism is still ***,we review the critical progress of defect engineering and provide an extensive way to modulate the properties depressed by *** insight into the defect engineering,we firstly introduce two common kinds of defects during the growth progress of TMDCs and the possible distribution of energy levels those defects could ***,various methods to improve point defects and grain boundaries during the period of growth are discussed intensively,with the assistance of which more large-area TMDCs films can be *** the defects in TMDCs are inevitable regardless of concentration,we also highlight strategies to heal the defects after *** dry methods or wet methods,the chalcogen vacancies can be repaired and thus,the performance of electronic device would be significantly ***,we propose the challenges and prospective for defect engineering in 2D TMDCs materials to support the optimization of device and lead them to wide applied fields.

关键词： defect repairing two-dimensional transition metal dichalcogenides

台湾当局“新南向政策”中“非经济”措施评析

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现代台湾研究 2018年第6期 51-58页

作者：李仕燕华南农业大学马克思主义学院

"新南向政策"出台以来,被民进党当局寄予厚望的经济手段至今收效甚微。但观察"新南向政策"架构中的"非经济"措施可以发现,民进党当局正在借"新南向"之名,打着"以人为本"的旗号,盘活"新南向"国家华侨人脉,输出"台湾主体性"价值观,培植"友... 详细信息

"新南向政策"出台以来,被民进党当局寄予厚望的经济手段至今收效甚微。但观察"新南向政策"架构中的"非经济"措施可以发现,民进党当局正在借"新南向"之名,打着"以人为本"的旗号,盘活"新南向"国家华侨人脉,输出"台湾主体性"价值观,培植"友台"力量,意在强化与"新南向"国家的实质关系,实现"国际空间"的"突破"。

关键词： “新南向政策” 民进党当局经济措施 “非经济”措施

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两岸网络民意交融:机遇、挑战与应对

现代台湾研究 2020年第3期 10-15页

作者：李仕燕华南农业大学马克思主义学院中国统一战线理论研究会港澳和海外统战工作理论广东研究基地

2008年以来,社交媒体对台湾社会与两岸关系的影响日益增强,如同一把"双刃剑",既可以成为两岸经济社会融合的助力,也可能给两岸关系和平发展带来阻力。特别是现阶段大陆社交媒体产品逐渐进入台湾市场,为两岸网络民意正向交流提供了条件,... 详细信息

2008年以来,社交媒体对台湾社会与两岸关系的影响日益增强,如同一把"双刃剑",既可以成为两岸经济社会融合的助力,也可能给两岸关系和平发展带来阻力。特别是现阶段大陆社交媒体产品逐渐进入台湾市场,为两岸网络民意正向交流提供了条件,却受到岛内政治因素的干扰。前瞻而言,促进两岸网络民意交融,在网络场域推动两岸心灵契合仍任重道远。

关键词：两岸交流社交媒体网络民意心灵契合