neutron soil moisture meter

例句：

1. 1. Neutrons are the building blocks of matter.
   中子是物质的构建块。
2. 2. The neutron star is a very dense object that contains an immense amount of energy.
   中子星是一个非常密集的对象，它包含了大量的能量。
3. 3. Neutrons are used in nuclear reactors to produce heat and electricity.
   中子用于核反应堆中产生热量和电力。