BET and XPS measurements revealed that the change of pore distribution, the partial loss of Ni and Ce species over the surface of Ni-Ce/Al 2O 3 after using for a long time in this reaction system are responsible for the decrease of the catalyst activity.是什么意思_BET and XPS measurements revealed that the change of pore distribution, the partial loss of Ni and Ce species over the surface of Ni-Ce/Al 2O 3 after using for a long time in this reaction system are responsible for the decrease of the catalyst activity.在线翻译_英语_读音_用法_例句