The drill collars must be made of nonmagneticmaterial.
钻铤必须是由非磁性物质做成的。
2
A nonmagnetic layer (7) made of nonmagneticmaterial is disposed over the reference layer.
由非磁性材料制成的非磁性层(7)设置于基准层之上。
3
To understand how these three ideas work together, it helps first to think about a lone nanoparticle made of some nonmagneticmaterial, its diameter a small fraction of an optical wavelength.