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- 電離層F2層Ionospheric F2-layer
- 用於對潛通訊的星載的ELF/VLF發射環天線處於350km高度的電離層F2層。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層臨界頻率the critical frequency of the F2 layer
- 層layer
- 多層multilayer
- 單層monolayer
- 三層three-layer
- 第一層first floor
- 內層lining
- 薄層folium
- 墊層cushion coat
- 層數number of plies
- 層高height between floors
- 層壓lamination
- 層板plywood
- 層的stratal
- 兩層two-layer
- 低層low level
- 中間層mesosphere
- 層析chromatography
