alternating current polar-ograph

例句：

1. 1. Thepolar-ograph was used to recordthe electrical properties of the sample.
   极谱仪被用来记录样品的电学性质。
2. 2. The polar-ograph was usedto analyze the chemical composition of the sample.
   极谱仪被用来分析样品的化学成分。
3. 3. The polar-ograph was usedto study the behavior of the sample underdifferent conditions.
   极谱仪被用来研究样品在不同条件下的行为。