ppm的用法

simulation of ion noise in ppm focused twt by particle-in-cell method

周期永磁聚焦行波管离子噪声的粒子模拟

Of 7 other brands of synthetic detergent powder also caused significant increases in frequencies of micro-nucleus at 12.0 ppm.

在我们实验条件下，另外7种合成洗衣粉中的5种在12.0ppm浓度组也引起微核率升高。

The residue of 35S-kitazin P in stored rice grains was very low. For the granule the value was not beyond 0.1 ppm in unpolished rice and increased as the irrigation water in depth.

~（35）S&异稻瘟净在收获水稻中的残留量是很低的，施用颗粒剂后，糙米中的残留量未超过0.1ppm，其残留量随着施用后一周内灌水深度的增加而增加。