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高旋转数内冷通道换热实验技术及验证

航空动力学报 2014年第8期29卷 1817-1823页

作者：程俊华倪彬邓宏武田淑青陈豪北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191 中国航空工业集团公司商用航空发动机有限责任公司设计研发中心上海201108

通过内冷通道换热理论分析及实验系统优化,获得了使内冷通道内气体压力保持在500kPa以上的高旋转数实验技术.旋转数和雷诺数的范围分别为0-2.08,10^4-7×10^4,极大满足了旋转数与雷诺数同时覆盖真实发动机涡轮叶片工作参数的实验需求.... 详细信息

通过内冷通道换热理论分析及实验系统优化,获得了使内冷通道内气体压力保持在500kPa以上的高旋转数实验技术.旋转数和雷诺数的范围分别为0-2.08,10^4-7×10^4,极大满足了旋转数与雷诺数同时覆盖真实发动机涡轮叶片工作参数的实验需求.证实了雷诺数和旋转数对内冷通道换热的影响可以解耦.而应用该实验技术进行同等旋转数实验时,内冷通道热损失占总加热量的比例和实验误差分别降低到18%和±10%.

关键词：高压高雷诺数高旋转数对流换热内冷通道实验技术

Kaibel分壁精馏塔分离芳烃的稳态和动态模拟

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化工学报 2015年第4期66卷 1353-1362页

作者：蔺锡钰吴昊沈本贤凌昊华东理工大学化学工程联合国家重点实验室上海200237

Kaibel分壁精馏塔(Kaibel divided-wall column,KDWC)可在一个塔内实现四组分混合物的高纯度分离。本文以分离苯、甲苯、二甲苯和均三甲苯为研究对象,建立了KDWC严格稳态模型,获得了优化的塔体结构。通过研究KDWC分离17组进料组成的基础... 详细信息

Kaibel分壁精馏塔(Kaibel divided-wall column,KDWC)可在一个塔内实现四组分混合物的高纯度分离。本文以分离苯、甲苯、二甲苯和均三甲苯为研究对象,建立了KDWC严格稳态模型,获得了优化的塔体结构。通过研究KDWC分离17组进料组成的基础上,获得了KDWC的稳态分离的初步规律:实现KDWC的高纯度分离,既需要通过分液比控制预分馏段顶部馏出气相中的二甲苯含量,又需要通过分气比控制预分馏底部馏出液相中甲苯含量;两个侧线的组成中,重组分杂质的含量要远多于轻组分杂质的含量;中间组分甲苯在预分馏段仍有返混。随后,在Aspen Dynamic环境下建立了KDWC的组分控制模型,控制结果表明该模型可以应对±10%的流量和进料组成波动,但二甲苯产品纯度会出现少量偏差。

关键词： Kaibel分壁精馏塔芳烃蒸馏分离稳态动态控制模拟

HIGH-CURRENT PULSED ELECTRON BEAM: RAPID SURFACE ALLOYING AND WEAR RESISTANCE IMPROVEMENT

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 276-282页

作者： J.Xu H.W.Liu Z.R.Zhou C.Dong A.M.wu S.Z.hao A.M.Zhang T.Xu TribologyResearchInstitute SouthwestJiaotongUniversityChengdu610031ChinaManuscriptreceived25November2002 StateKeyLab.forMaterialsModificationbyLaser IonandElectronBeamsDalianUniversityofTech-nologyDalian116024China StateKeyLaboratoryofSolidLubrication LanzhouInstituteofChemicalPhysicsTheChineseAcademyofSciencesLanzhou730000China

The present paper reports the rapid surface alloying induced by the bombardment of high-current pulsed electron beam. Two kinds of substrate materials were examined to show this effect. The first sample was a pure Al metal pre-coated with fine carbon powders prior to the bombardment, and the second alloy is the D2-Crl2MolVl mould steel pre-coated with Cr, Ti, and TiN powders. The surface elements diffuse about several micrometers into the substrate materials only after several bombardments. Tribological behaviors of these samples were characterized and significant improvement in wear resistance was found. Finally, a TEM analysis reveals the presence of stress waves generated by coupled thermal and stress fields, which was considered as the main cause of the enhanced properties.

关键词： high-current pulsed electron beam surface alloying tribology fretting wear

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突变和修饰β淀粉样蛋白与阿尔茨海默病

生物化学与生物物理进展 2022年第1期49卷 100-112页

作者：郝秀萍武林芝太原学院材料与化学工程系太原030032

淀粉样蛋白级联假说是阿尔茨海默病(Alzheimer’s disease,AD)病因学的核心,但在过去几年中,靶向淀粉样斑块并未实现成功的免疫治疗。最近几年,不同形式的β淀粉样蛋白(Aβ)引起人们的关注。本文总结了关于早发性AD患者大脑中不同Aβ突... 详细信息

淀粉样蛋白级联假说是阿尔茨海默病(Alzheimer’s disease,AD)病因学的核心,但在过去几年中,靶向淀粉样斑块并未实现成功的免疫治疗。最近几年,不同形式的β淀粉样蛋白(Aβ)引起人们的关注。本文总结了关于早发性AD患者大脑中不同Aβ突变体和散发性AD患者大脑中已经鉴定出的经过酶切及修饰产生的不同形式Aβ的研究进展,重点阐述了这些Aβ的聚集特性和在AD发展中的影响,并对目前报道的Aβ变体检测分析方法进行了概述。本文旨在为今后深入研究不同形式的Aβ及相关分子在AD病理过程中的作用、开发诊断和治疗AD新方法提供参考。

关键词：阿尔茨海默病突变Aβ 修饰Aβ 聚集特性病理特性检测方法

自由梁在一端受局部三角形脉冲载荷时的塑性动力响应

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北京理工大学学报 2011年第9期31卷 1009-1012页

作者：郝陈朋吴成北京理工大学机电学院北京100081

为了估计局部爆炸载荷对飞行器的影响,采用刚塑性模型分析了自由梁在一端受局部脉冲载荷作用时的塑性动力响应,给出了不同载荷长度作用下梁的变形模式,最后分析了航天飞机在局部脉冲载荷下的断裂问题.研究表明,飞行器在一端受局部的脉... 详细信息

为了估计局部爆炸载荷对飞行器的影响,采用刚塑性模型分析了自由梁在一端受局部脉冲载荷作用时的塑性动力响应,给出了不同载荷长度作用下梁的变形模式,最后分析了航天飞机在局部脉冲载荷下的断裂问题.研究表明,飞行器在一端受局部的脉冲载荷下更不容易发生断裂.

关键词：自由梁塑性动力响应局部脉冲载荷

The Research of Connection between Degree of Polymerization and Frequency Domain Dielectric Spectroscopy Characteristics during Oil-Paper Insulation Aging

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Energy and Power Engineering 2017年第4期9卷 667-674页

作者： Danyu Jiang Guangning wu Xian Yang Qingkai hao ASchool of Electrical Engineering College Southwest Jiaotong University Chengdu China Electric Power Research Institute of Guangdong Power Grid Corporation Guangzhou China

In order to study the linkage effects between degree of polymerization and frequency domain dielectric spectroscopy characteristics of oil-paper insulation, the frequency domain dielectric response test platform of oil-paper insulation is set up. Complex permittivity of oil-paper insulation respectively composed by new or aged oil and insulation paper with different DP are tested, and complex permittivity of oil-paper insulation respectively composed by insulation respectively composed by new oil and insulation paper with different DP and low or high moisture content are tested. The test results are analyzed, and the analysis results show that the degree of polymerization of insulation paper has an influence on complex permittivity of oil-paper insulation though influencing the distribution of moisture and acids between oil and paper.

关键词： Degree of Polymerization Oil-Paper Insulation Frequency Domain Dielectric Spectroscopy Moisture

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载荷敏度抑制下涡轮盘拓扑优化及结构演化

航空学报 2022年第5期43卷 339-348页

作者：闫浩吴晓明厦门大学航空航天学院厦门361102

航空发动机涡轮盘工作时承受的离心载荷是一种典型设计相关载荷,这类问题的变密度结构拓扑优化需要解决低密度单元的材料附属效应和目标函数非单调等求解上的困难。基于变密度拓扑优化模型,运用指数型材料性能近似(EAMP)模型避免材料附... 详细信息

航空发动机涡轮盘工作时承受的离心载荷是一种典型设计相关载荷,这类问题的变密度结构拓扑优化需要解决低密度单元的材料附属效应和目标函数非单调等求解上的困难。基于变密度拓扑优化模型,运用指数型材料性能近似(EAMP)模型避免材料附属效应并提高收敛速度;构造了一种新的灰度抑制方法减小拓扑结构灰度;提出载荷敏度抑制算法求解设计相关载荷的拓扑优化问题。算例表明算法有效并且灰度单元少、收敛速度快。通过载荷敏度抑制系数讨论,从拓扑优化算法角度揭示了传统单辐板涡轮盘与近年广泛研究的双辐板涡轮盘结构之间的联系及演化规律。

关键词：设计相关载荷材料插值模型灰度抑制涡轮盘拓扑优化

Recent developments of quantum dot based micro-LED based on non-radiative energy transfer mechanism

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Opto-Electronic Advances 2021年第4期4卷 1-15页

作者： Xiaotong Fan Tingzhu wu Bin Liu Rong Zhang hao-Chung Kuo Zhong Chen School of Electronic Science and Engineering Fujian Engineering Research Center for Solid-State LightingXiamen UniversityXiamen 361005China Fujian Science&Technology Innovation Laboratory for Energy Materials of China Xiamen 361005China Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials Nanjing National Laboratory of MicrostructuresSchool of Electronic Science and EngineeringNanjing UniversityNanjing 210093China Department of Photonics and Graduate Institute of Electro-Optical Engineering College of Electrical and Computer EngineeringChiao Tung UniversityHsinchu 30010China

With regard to micro-light-emitting diodes(micro-LEDs),their excellent brightness,low energy consumption,and ultrahigh resolution are significant ***,the large size of traditional inorganic phosphors and the number of side defects have restricted the practical applications of small sized ***,quantum dot(QD)and nonradiative energy transfer(NRET)have been proposed to solve existing *** possess nanoscale dimensions and high luminous efficiency,and they are suitable for NRET because they are able to nearly contact the micro-LED *** NRET between QDs and micro-LED chip further improves the color conversion efficiency(CCE)and effective quantum yield(EQY)of full-color micro-LED *** this review,we discuss the NRET mechanism for QD micro-LED devices,and then nano-pillar LED,nano-hole LED,and nano-ring LED are introduced in *** structures are beneficial to the NRET between QD and micro-LED,especially nano-ring ***,the challenges and future envisions have also been described.

关键词： quantum dot based micro-LED non-radiative energy transfer atomic layer deposition sidewall defects

Prevalence of sensitization to weed pollens of Humulus scandens,Artemisia vulgaris,and Ambrosia artemisiifolia in northern China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第3期14卷 240-246页

作者： Guo-dong hao Yi-wu ZHENG Birgitte GJESING Xing-ai KONG Jing-yuan WANG Zhi-jing SONG Xu-xin LAI Nan-shan ZHONG Michael D.SPANGFORT Department of Allergy Tangshan Gongren Hospital Research Asia Pacific ALK-Abelló A/S State Key Laboratory of Respiratory Diseases Guangzhou Medical University

Objective:Weed pollens are common sources of allergens *** prevalence of weed pollen sensitization is not yet fully known in *** purpose of this study was to investigate the prevalence of sensitization to weed allergens from Artemisia,Ambrosia,and Humulus in northern ***:A total of 1144 subjects(aged from 5 to 68 years) visiting our clinic from June to October 2011 underwent intradermal testing using a panel of 25 allergen *** with positive skin responses to any pollen were further tested for their serum concentrations of IgE antibodies against Artemisia vulgaris,Ambrosia artemisiifolia,and Humulus scandens,and against the purified allergens,Art v 1 and Amb a ***:Of 1144 subjects,170 had positive intradermal reactions to pollen and 144 donated serum for IgE *** prevalence of positive intradermal responses to pollens of Artemisia sieversiana,Artemisia annua,***,and *** was 11.0%,10.2%,3.7%,and 6.6%,*** the intradermal positive subjects,the prevalence of specific IgE antigens to *** was 58.3%,to *** 14.7%,and to *** 41.0%.The prevalence of specific IgE antigens to the allergen Art v 1 was 46.9%,and to Amb a 1 was 11.2%.The correlation between the presence of IgE antibodies specific to *** and to the Art v 1 antigen was very *** with *** specific IgE also had *** specific IgE,but with relatively high levels of *** IgE *** were no correlations between the presence of IgE antibodies to *** and *** or to *** and ***:The intradermal prevalence of weed pollen sensitization among allergic subjects in northern China is about 13.5%.Correlations of specific IgE antibodies suggest that pollen allergens from Artemisia and Humulus are independent sources for primary sensitization.

关键词： Humulus scandens Artemisia vulgaris Ambrosia artemisiifolia Intradermal test Specific IgE Sensitization