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湖北地区砖室墓砌筑研究
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作者 罗廷 郑雷 《收藏与投资》 2024年第8期68-70,共3页
砖室墓最早发源于汉代,是我国古代社会一种重要的墓葬形制。砖室墓不仅体现了古代葬俗文化,更是古建筑的重要形式。通过收集已发表的关于湖北地区砖室墓的考古资料,分析各时代砖室墓的砌筑方法和建筑风格,本文以墓室内部墓壁的砌筑以及... 砖室墓最早发源于汉代,是我国古代社会一种重要的墓葬形制。砖室墓不仅体现了古代葬俗文化,更是古建筑的重要形式。通过收集已发表的关于湖北地区砖室墓的考古资料,分析各时代砖室墓的砌筑方法和建筑风格,本文以墓室内部墓壁的砌筑以及墓底的铺设为重点,总结砖室墓各时期的发展演变特征。 展开更多
关键词 砖室墓 砌筑 顺丁结合
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Influence of external nitrogen-containing donors on polymerization behavior of neodymium-based cis-1,4-polybutadiene rubber
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作者 LI Xin DONG Jing +3 位作者 HAN Zhuo-ling WANG Feng ZHANG Xue-quan LIU Heng 《合成橡胶工业》 CAS 2024年第5期438-438,共1页
Neodymium(Nd)-based catalyst in butadiene(Bd)polymerization has drawn interests due to its availability in affording higher cis-1,4-unit selectivity than transition metal(Ti,Co,Ni,etc.)-based catalysts[1-2].Such outst... Neodymium(Nd)-based catalyst in butadiene(Bd)polymerization has drawn interests due to its availability in affording higher cis-1,4-unit selectivity than transition metal(Ti,Co,Ni,etc.)-based catalysts[1-2].Such outstanding high cis-1,4-unit selecti-vity is hypothetically originated from the presence of 4 f orbitals,that can participate in monomer coordination and thereby govern subsequent enchainment manners.This unique characteristic also renders the active species highly susceptible to Lewis bases,and may impact the overall selectivity as well as polyme-rization behavior after coordination.Nevertheless,it is still a virgin area in such a field,and the influence of Lewis bases on Nd-based diene polymerizations is still a black box.Based on this consideration,how nitrogen-containing donors(D)impacts the overall behaviors of Nd-mediated Bd polymerizations is disclosed. 展开更多
关键词 POLYMERIZATION BASES SELECTIVITY
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