impurityn.不纯;杂质
impurity density杂质浓度
Impurity of iron含铁杂质
impurity content杂质含量
impurity removal除杂
impurity control杂质控制
impurity of seed种子不纯度
impurity element杂质元素
impurity of seeds种子混杂
impurity tungsten杂质钨
impurity gradient杂质梯度