邻居们无疑都听到了低空飞过的直升飞机，其中一架坠落的声音和不时的爆炸与相继的枪声。但没有人出来。

Neighbors undoubtedly heard the low-flying helicopters the sound of one crashing and the sporadic explosions and gunfire that ensued but nobody came outside.

youdao

本文主要研究高空核爆炸在大气中产生的电子密度分布，同时给出低空核爆的部分结果。

This paper mainly studies the distribution of the electron density produced by the high-altitude nuclear burst in atmosphere and gives part o the results at low-altitude.

youdao

本文主要研究高空核爆炸在大气中产生的电子密度分布，同时给出低空核爆的部分结果。

This paper mainly studies the distribution of the electron density produced by the high-altitude nuclear burst in atmosphere and gives part o the results at low-altitude.

youdao