Precasting the caissons with the sliding frame and manu al moving forms technology 采用滑框倒模技术预制沉箱
2.
Slide projectors and slides - part 56 : slide frames and lantern slides for general use and for theatre projection ; certification scheme 幻灯机和幻灯片.第56部分:通用和影剧院用幻灯片和幻