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支柱型复合片钻头外圈支柱镶嵌孔位置的确定
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作者 唐胜利 《煤田地质与勘探》 CAS CSCD 北大核心 1990年第4期61-64,共4页
分析了支柱复合片钻头外圈镶嵌孔位对钻头直径的影响,介绍了用数学方法求解孔位的过程。
关键词 支柱型 复合片 钻头 镶嵌孔 位置
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A highly stable and active mesoporous ruthenium catalyst for ammonia synthesis prepared by a RuCl_3/SiO_2-templated approach 被引量:7
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作者 Yaping Zhou Yongcheng Ma +4 位作者 Guojun Lan Haodong Tang Wenfeng Han Huazhang Liu Ying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第1期114-123,共10页
Molecular nitrogen is relatively inert and the activation of its triple bond is full of challenges and of significance.Hence,searching for an efficiently heterogeneous catalyst with high stability and dispersion is on... Molecular nitrogen is relatively inert and the activation of its triple bond is full of challenges and of significance.Hence,searching for an efficiently heterogeneous catalyst with high stability and dispersion is one of the important targets of chemical technology.Here,we report a Ba‐K/Ru‐MC catalyst with Ru particle size of 1.5–2.5 nm semi‐embedded in a mesoporous C matrix and with dual promoters of Ba and K that exhibits a higher activity than the supported Ba‐Ru‐K/MC catalyst,although both have similar metal particle sizes for ammonia synthesis.Further,the Ba‐K/Ru‐MC catalyst is more active than commercial fused Fe catalysts and supported Ru catalysts.Characterization techniques such as high‐resolution transmission electron microscopy,N2 physisorption,CO chemisorption,and temperature‐programmed reduction suggest that the Ru nanoparticles have strong interactions with the C matrix in Ba‐K/Ru‐MC,which may facilitate electron transport better than supported nanoparticles. 展开更多
关键词 Mesoporous carbon Semi‐embedded Ru/Carbon catalyst High dispersion Ammonia synthesis
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Formation mechanism of highly dispersed semi-embedded ruthenium nanoparticles in porous carbon matrix determined by in situ temperature-programmed infrared spectroscopy 被引量:3
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作者 Guojun Lan Yaping Zhou +2 位作者 Hangjia Shen Haodong Tang Ying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第1期146-156,共11页
The carbonization process of a sucrose‐RuCl3/SBA‐15composite towards a Ru‐containing ordered mesoporous carbon(Ru‐OMC)catalyst was studied by in situ temperature‐programmed infrared spectroscopy to identify the s... The carbonization process of a sucrose‐RuCl3/SBA‐15composite towards a Ru‐containing ordered mesoporous carbon(Ru‐OMC)catalyst was studied by in situ temperature‐programmed infrared spectroscopy to identify the stabilization role of organic carbon precursors during the formation of highly dispersed Ru nanoparticles.The results show that the formation of metal carbonyl species results in the formation of homogeneously distributed Ru nanoparticles,and the rigid silica support and carbon matrix around the Ru(CO)x complex can significantly avoid the sintering and agglomeration of Ru metal particles during elevated temperature thermal treatment.These results ultimately demonstrate that sucrose plays important roles in the formation of homogeneously distributed Ru nanoparticles in a porous carbon matrix.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved. 展开更多
关键词 Ruthenium nanoparticles Infrared spectroscope in‐situ Ru‐containing ordered mesoporous carbon Mesoporous carbon
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