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CT local reconstruction of solid rocket motor based on PI-POCS-TVM

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航空动力学报 2017年第2期32卷 470-476页

作者： LU Hong-yi chen qing-gui ZHU Min LI Peng ZHAO Ru-yan WANG Bin Airborne Vehicle Engineering Department Naval Aeronautical and Astronautical University Yantai Shandong 264001 China qingdao Branch Naval Aeronautical and Astronautical University Qingdao Shandong 266041 China No. 7 Department Naval Aeronautical and Astronautical University Yantai Shanctong 264001 China

In order to test the defects of solid rocket motor(SRM)accurately and efficiently,the computed tomography(CT)inspection scheme for SRM's defects was investigated and a CT local reconstruction algorithm called prior information-projection onto convex sets-total variation minimization(PI-POCS-TVM)was *** SRM was first inspected by industrial CT(ICT)to generate a low-resolution SRM image used as the prior information,then high-resolution local inspection was carried out for SRM's *** validate the effectiveness of the CT inspection scheme for SRM's defects,one SRM was inspected by a narrow fan beam ICT *** back projection(FBP)algorithm,POCS,POCS-TVM and PI-POCS-TVM algorithms were applied to reconstruct CT *** performance of these algorithms was also *** demonstrated the effectiveness of the CT inspection scheme for SRM's ***,the PI-POCS-TVM algorithm has better local reconstruction image quality than the other three algorithms,showing great significance for accurate measurement of SRM's defects.

关键词： interior tomography exterior tomography compressed sensing prior information projection onto convex sets-total variation minimization(POCS-TVM) solid rocket motor

Electron Beam-Physical Vapor Deposited TiAl-based Laminated Composite Sheet with Nb Layer Toughening

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Chinese Journal of Aeronautics 2006年第B12期19卷 5-8页

作者： ZHANG De-ming chen gui-qing HAN Jie-cai MENG Song-he Center for Composite Materials Harbin Institute of Technology Harbin 150080 China

The TiAl-based laminated composite sheet of 150 mm × 100 mm × 0.2 mm, with 24 TiAl layers and 23 Nb layers laid alternately one on another, was successfully fabricated using the electron beam-physical vapor deposition （EB-PVD） method. The microstructure and properties of the sheet were investigated on an atomic force microscope （AFM）, a scanning electron microscope （SEM） and a tensile testing machine. The results indicate that the evenly distributed Nb layers are well joined with the TiAl layers, and the interfaces between layers are transparent, and every interlayer spacing is of about 8μm. The fractures appear to be a mixture of intergranular fractures and somewhat ductile quasi-cleavage ones. Despite its slight influence on ultimate tensile strength, the inserts of Nb layers efficiently increase the room temperature ductility of TiAl-based alloys due to the crack deflection effect.

关键词： EB-PVD TiAl-based alloys sheet TiAl/Nb laminated composites microstructure and properties

Heteroepitaxial Growth of Single-Crystalline Diamond Film

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Chinese Physics Letters 1998年第11期15卷 819-821页

作者： WANG Qi-min chen qing-gui SHI Ri-hua DONG Rong-kang NI Ru-shan ZHU Ji-qian State Key Laboratory of Transducer Technology Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050

Using high temperature heteroepitaxial growth method the single-crystalline diamond film growth conditions have been studied by Raman spectrum and transmission electron *** temperature,low alcohol concentration,slow gas flow velocity,long epitaxial time and substrate located near the gas exit side on the susceptor are the favourable conditions for growing single-crystalline diamond film.

关键词： diffraction. film. epitaxial

Dicoumarol Alters Cellular Redox State and Inhibits Nuclear Factor Kappa B to Enhance Arsenic Trioxide-Induced Apoptosis

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 235-242页

作者： Ya-Wu JING, Jing YI, Yu-Ying chen, qing-Shen HU, gui-Ying SHI, Hue LI, and Xue-Ming TANG* Department of Cell Biology, Shanghai Second Medical University, Shanghai 200025, China Department of Cell Biology Shanghai Second Medical University

The effects of a number of cytotoxic drugs are influenced by cellular reduction/oxidation (redox) state. In the present study, we attempt to explore if dicoumarol, an inhibitor of NADPH: quinone oxidoreductase (NQO1), alters the cellular redox state and how this alteration affects the redox-related apoptosis. Flow cytometry was used to assess the reactive oxygen species (ROS) level and apoptotic rates of HeLa cells treated with arsenic trioxide (As2O3) alone or in combination with natural anthraquinone emodin and dicoumarol or plus N-acetyl-cysteine. Western blot, immunofluorescence, electrophoretic mobility shift assay and luciferase assay were used to detect Nuclear Factor kappa B (NF-κB) activation. The results showed that dicoumarol synergized with emodin to sensitize HeLa cells to As2O3-induced apoptosis through raising the ROS level. More notably, this enhanced susceptibility was associated with a ROS-mediated inhi- bition of NF-κB activation in which the combinative treatment with dicoumarol prevented NF-κB from binding to target DNA. It was suggested that dicoumarol in combination with anthraquinones might be a novel strategy to expand the chemotherapeutic spectrum of As2O3 by means of interfering the cellular redox state.

关键词： dicoumarol arsenic trioxide reduction/ oxidation state apoptosis NF-κB

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清代词学与易学

周易研究 2011年第3期 89-96页

作者：陈桂清中山大学中文系广东广州510275

易学是清代词学重要的理论源泉,在清代词学理论的构建中,无论是词的创作心态、技法,还是词学审美观、词学诠释学,乃至词学的发展史论等,均受到易学不同程度的影响。易学中的"修辞立其诚"、取"象"、"阴阳刚柔"、"仁者见仁,智者见智"、本... 详细信息

易学是清代词学重要的理论源泉,在清代词学理论的构建中,无论是词的创作心态、技法,还是词学审美观、词学诠释学,乃至词学的发展史论等,均受到易学不同程度的影响。易学中的"修辞立其诚"、取"象"、"阴阳刚柔"、"仁者见仁,智者见智"、本色自然、变通发展的理论均渗透到词学领域,滋润灌溉了清代词学。

关键词：清代词学易学创作审美诠释

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液压油缸深焊缝窄坡口设计

液压与气动 2012年第6期36卷 98-100页

作者：陈贵清重庆三峡职业学院重庆404002

液压机油缸是液压机上的一个关键件,要求承受较高的抗拉强度,为节约生产成本目前大型油缸多采用拼焊工艺。按GB/T985.2-2008《埋弧焊的推荐坡口》进行坡口设计坡口宽度宽,需要填充的焊料较多又增加焊接时间。为提高效率,通过对焊接过程... 详细信息

液压机油缸是液压机上的一个关键件,要求承受较高的抗拉强度,为节约生产成本目前大型油缸多采用拼焊工艺。按GB/T985.2-2008《埋弧焊的推荐坡口》进行坡口设计坡口宽度宽,需要填充的焊料较多又增加焊接时间。为提高效率,通过对焊接过程的工况进行分析,采用深焊缝窄坡口设计,对焊接设备进行合理选择,调整焊接工艺,从而有效地减少了焊缝的宽度,提高了焊接效率。

关键词：深焊缝窄坡口埋弧焊

煤矿机械生产中石墨/铁基耐磨复合材料的应用研究

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煤矿机械 2014年第6期35卷 202-204页

作者：陈贵清陈小刚重庆三峡职业学院重庆404155

对复合材料中应用较广的石墨/铁基耐磨复合材料的性能及制作方法进行了阐述,并结合煤矿罐笼衬套对其在煤矿机械生产中的应用进行了实例分析,以期促进我国煤矿机械生产和石墨/铁基耐磨复合材料研究的进步。

关键词：煤矿机械生产石墨铁基耐磨复合材料

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液压支架涂装设计分析

煤矿机械 2014年第5期35卷 118-120页

作者：陈贵清陈小刚重庆三峡职业学院重庆404155

主要针对液压支架产品的特点及涂装工艺方案进行分析,给出了液压支架涂装工艺设计与平面布置,然后介绍几种主要的涂装设备。

关键词：煤矿机械生产工艺设计液压支架涂装

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珍珠和贝壳的晶体结构新结论

应用海洋学学报 2017年第4期36卷 528-532页

作者：陈贵卿陈俊豪暨南大学广东广州510630

国内外贝类学界都认为贝壳角质层仅由贝壳素构成.棱柱层由方解石构成.珍珠层通常为霰石构成.日本的小林新二郎提出棱柱珍珠是方解石结构,国内外许多论文对此都没有提出异议.本研究采用X-射线对贝壳和棱柱珍珠衍射结果证明:(1)贝壳珍珠... 详细信息

国内外贝类学界都认为贝壳角质层仅由贝壳素构成.棱柱层由方解石构成.珍珠层通常为霰石构成.日本的小林新二郎提出棱柱珍珠是方解石结构,国内外许多论文对此都没有提出异议.本研究采用X-射线对贝壳和棱柱珍珠衍射结果证明:(1)贝壳珍珠层全是是霰石结构,只有牡蛎(Ostrea rivularis)壳例外,符合以上理论;(2)棱柱层几乎全是霰石结构,只有牡蛎壳和紫色裂江珧(Pinna atropurpurea)壳的棱柱层是方解石结构,基本否定了以上理论;(3)角质层由有机物—贝壳素和方解石或霰石组成的,有些还含二氧化硅等杂质,这不完全相符上面理论;(4)棱柱珍珠完全是霰石结构,证明小林新二郎的结论是错误的.

关键词：海洋生物学 X-射线衍射霰石结构方解石结构棱柱珍珠