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- 电离层F2层Ionospheric F2-layer
- 用于对潜通讯的星载的ELF/VLF发射环天线处于350km高度的电离层F2层。The spaceborne VLF/ELF loop antenna for the communications to submarines is a loop wire in the F-layer of the ionosphere at a height of 350 km.
- F2层临界频率the critical frequency of the F2 layer
- 层layer
- 多层multilayer
- 单层monolayer
- 三层three-layer
- 第一层first floor
- 内层lining
- 薄层folium
- 垫层cushion coat
- 层数number of plies
- 层高height between floors
- 层压lamination
- 层板plywood
- 层的stratal
- 两层two-layer
- 低层low level
- 中间层mesosphere
- 层析chromatography
