您要查找的是不是：
- 时现E层 sporadic E layer
- 极光时现E层 auroral sporadic E layer
- 中纬度时现E层 midlatitude sporedic E layer
- 在中纬度中和时现E层分子和金属离子的相对浓度 Relative concentrations of molecular and metallic ions in midlatitude intermediate and sporadic-E layers
- 赤道时现E层 equatorial sporadic E layer
- 层 layer
- 赤道偶现E层 equatorial sporadic E layer
- 几时 what time; when
- 报时 give the correct time
- 单层 monolayer
- 人时 man-hour
- 套现 arbitrage
- 顺时 up time; be in luck; on time
- 内层 lining
- 初现 peep
- 薄层 folium
- 必要时 in a pinch
- 折现 realization
- 层数 number of plies
- 限时 in limited time
