增加密度
To make the density greater.
使密度变大。
降低密度
To make the density smaller.
使密度变小。
测量密度
To find the density by using an instrument.
用仪器找出密度。
测定密度
To discover or establish the density exactly.
准确地发现或确定密度。
计算密度
To find the density using mathematical methods.
用数学方法求出密度。
估计密度
To make an approximate calculation of density.
对密度进行近似计算。