纳米是一种长度度量单位 ,1纳米等于 10亿分之一米 (1纳米 =10 -3 微米 =10 -9米 ) ,相当于头发丝直径的 10万分之一。纳米表示符号为ｎｍ。纳米材料 ,是指晶粒尺寸为纳米级 (10 -9ｍ )的超细材料。其尺寸介于分子、原子与块状材料之间 ,通常泛指 1—10 0ｎｍ范围内的微小固体 Nanometer is a measure of length, 1 nanometer is equal to 1 billionth of a meter (1 nanometer = 10 -3 microns = 10 -9 meters), equivalent to one hundred thousandth of the diameter of the hair wire. The symbol of nanometer is nm. Nanomaterials are ultrafine materials with a grain size of nanometers (10 -9 m). Its size is between molecules, atoms and bulk materials, usually refers to the tiny solid 1-10-10nm range