所以只要容器内SF 6气体不发生泄漏，其密度不变化。

So the SF6 gas does not occur divulges, its density does not change.

youdao

假设你被缩小到一枚硬币那么大，你的质量也同比例缩小以保持你的密度不变。

You are shrunk to the height of a nickel and your mass is proportionally reduced so as to maintain your original density. You are then thrown into an empty glass blender.

youdao

现有技术中的阀门不能根据液体的密度变化控制阀的开启状况，从而保持液体的密度不变。

In available technology, there is no valve with controlled opening based on the density of liquid to maintain unchanged liquid density.

youdao