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Synthesis of MgO-Al_2O_3/ZSM-5 by Solid State Reaction for Propane Dehydrogenation 被引量:2
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作者 Zhou Shijian ZhouYuming +4 位作者 Sheng Xiaoli ZhangYiwei Zhang Zewu Shi Junjun Kong Jie 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第3期50-56,共7页
Solid-state grinding is a simple and effective method to introduce guest species into the channels of microporous materials through filling.The structure and the surface acidity of the materials were obtained from BET... Solid-state grinding is a simple and effective method to introduce guest species into the channels of microporous materials through filling.The structure and the surface acidity of the materials were obtained from BET isotherms and NH3-TPD,respectively.XRD,UV-vis,UV diffuse-reflectance,and TEM were used to characterize the phases,and the morphology,respectively.The clustered layers of MgO-Al2O3phases were formed in the internal pore surface and were highly dispersed inside the channels of the ZSM-5 host.So the volume of MgO-Al2O3/ZSM-5 composite was larger than the ZSM-5 zeolite itself and some mesoporous channels appeared when Mg/Al species entered the channels.Meanwhile,new acid sites emerged in MgO-Al2O3/ZSM-5 composite and the acid amount of the sample changed.The improved Pt dispersion and the increased acid content would cause the increase of propane conversion and the modification of selectivity during the reaction. 展开更多
关键词 MGO-AL2O3 solid state reaction PTSN propane dehydrogenation
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大幅提高视觉密度国家基准测量水平的方法研究 被引量:3
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作者 刘子龙 陈锐 +2 位作者 廖宁放 李在清 王煜 《物理学报》 SCIE EI CAS CSCD 北大核心 2012年第23期133-138,共6页
随着生物医学影像和航天军事测量的发展,对用于光学成像底片和视觉校正的视觉密度的测量范围和不确定度的要求越来越高.以自行设计的光纤半球发射器形成的复合漫射器为特征的新方案将视觉漫透射密度国家基准的光源漫射系数提高到0.945,... 随着生物医学影像和航天军事测量的发展,对用于光学成像底片和视觉校正的视觉密度的测量范围和不确定度的要求越来越高.以自行设计的光纤半球发射器形成的复合漫射器为特征的新方案将视觉漫透射密度国家基准的光源漫射系数提高到0.945,比欧美国家基准高0.02—0.03.实验得到新基准的测量范围为0—6.0,合成不确定度为0.0015(0<D<4.5)和0.0054(5.0≤D<6.0),相比国际先进水平大幅提高.同时整体结构化的设计可以实现光源组件和探测组件的对调安装,用实验的方法在国际上首次验证了透射测量亥姆霍兹倒易律的有效性. 展开更多
关键词 视觉密度计量 不确定度 复合漫射 亥姆霍兹倒易律
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