The zinc powders are classified as ordinary, fine and ultra-fine according to the grain diameter and spherical, lamellar and irregular according to the grain shape.
锌粉按粒径大小可分为普通锌粉、细锌粉和超细锌粉，按形状可分为球状锌粉、片状锌粉和不规则形状锌粉。
2
The results showed that the pollen shapes of all 11 cultivars were near spherical in equatorial view. The size of pollen grain showed great variation among cultivars.
结果表明：11份花粉都呈近球形，花粉粒大小在所观察的材料间有较大差异。
3
The results of transmission electron microscopy(TEM) showed that the grain of strontium titanate powder prepared was spherical and the grain sizes distribution were homogeneous.