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Fabrication of La1-xCaxFeO3 perovskite-type oxides with macro-mesoporous structure via a dual-template method for highly efficient soot combustion

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Journal of Rare Earths 2020年第4期38卷 369-375页

作者： Minjie Zhao Jixing Liu Jian Liu Junfeng Xu Zhen Zhao Yuechang Wei Weiyu Song State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China

A series of three-dimensionally ordered macro-mesoporous(3DOMM)La1-xCaxFeO3(x=0-0.3)perovskite-type oxides were designed and successfully fabricated for the first time via a dual-template *** which,PMMA and Brij-56 were employed as the hard template and soft template,*** is found that 3 DOMM La1-xCaxFeO3 exhibits abundant wormlike mesoporous channels about 3 nm in diameter on macroporous skeleton *** excellent catalytic activity of soot combustion benefits from not only the well-designed hierarchical porous structure of catalyst,but also the redox electron pair of Fe3+/Fe4+induced by the doping of low-valent alkaline earth metal Ca to A-site of LaFeO3.3DOMM La0.8Ca0.2FeO3 exhibits superior catalytic performance for soot combustion,which shows T50 of396℃.It is 189℃lower than that without catalyst.A combination of structure and composition in the design of catalyst can be widely extended to other catalytic systems.

关键词： three-dimensionally ordered macro-mesoporous structure Perovskite-type oxides Lanthanum ferrite Soot combustion Rare earths

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Preparation and characterization of 3-dimensionally ordered macroporous SiC

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Science China(Technological Sciences) 2006年第1期49卷 1-9页

作者： KIM Dong-pyo Department of Fine Chemical Engineering and Chemistry of Chungnam National University Taejon 305-764 South Korea

three-dimensionally (3D) long range ordered macroporous SiC ceramics were prepared through infiltrating polymethylsilane (PMS) into the 3D ordered sacrificial silica template, pyrolysis and the template removal. It was found that the pore size (84―658 nm), BET surface area (299.44―584.64 m2/g) and micropore volume (0.25―0.64 cm3/g) of the achieved porous SiC can be tailored by utilizing different sizes silica sphere templates. There exist three kinds of pores in the porous ceramics: sphere inversed pores, windows and mesopores (2―5 nm). The sphere inversed pores were packed as hcp structure and three dimensionally penetrated through the windows, and the mesopores endowed the porous ceramics surprising high BET surface areas and micropore volumes.

关键词： three-dimensionally ordered materials, templated technique, preceramic polymer conversion technique, SiC ceramic.

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Effects of Fiber Volume on Modal Response of Through-Thickness Angle Interlock Textile Composites

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Open Journal of Composite Materials 2014年第1期4卷 40-46页

作者： Marco Villa Richard D. Hale Mark Ewing Department of Aerospace Engineering University of Kansas Lawrence USA mv2space LLC Boulder USA

Prior static studies of three-dimensionally woven carbon/epoxy textile composites show that large interlaminar normal and shear strains occur as a result of layer waviness under static compression loading. This study addresses the dynamic response of 3D through-thickness angle interlock textile composites, and how interaction between different layer waviness influences the modal frequencies. The samples have common as-woven textile architecture, but they are cured at varying compaction pressures to achieve varying levels of fiber volume and fiber architecture distortion. Samples produced have varying final cured laminate thickness, which allows observations on the influence of increased fiber volume (generally believed to improve mechanical performance) weighed against the increased fiber distortion (generally believed to decrease mechanical performance). The results obtained from this study show that no added damping was developed in the as-woven identical panels. Furthermore, a linear relation exists between modal frequency and thickness (fiber volume).

关键词： three-dimensionally Woven Textile Interlaminar Weaviness Dynamic Damping

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华南地区奥斯坦型保存化石的研究进展（英文）

华南地区奥斯坦型保存化石的研究进展（英文）

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中国古生物学会第十二次全国会员代表大会暨第29届学术年会

作者：刘政 Department of the Stratigraphy & Palaeontology The Geological Museum of China

Orsten-type fossils are mostly arthropods which are tiny but three-dimensionally preserve soft-bodies with secondarily phosphatized *** from Chengjiang Biota,Orsten-type fossils are with no obvious deformationdue to vertical extrusion,and represents a special type of ***-type fossils show exquisite morphological features of organisms when they were alive,thus providing important morphological evidence for studies on growth modes,phylogenetic classification and ontogenesis of *** over two decades,Chinese paleontologists have been persistently searching such type of fossils in Cambrian *** China is one of the important places in the world where Orsten-type fossils have been found,and possesses potential fossil resources to be studied in an in-depth ***,the related study of Orstentype fossils are doubtfully challengeable.

关键词： Orsten-type Fossil Lagerst?tte Cambrian Southern China Soft body Arthropod three-dimensionally

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