pfeilring reagent

例句：

1. 1. The pfeilringreagent was used to test the accuracyof the pH meter.
   滴定试剂被用来测试pH计的准确性。
2. 2. The chemicalanalyst used the pfeilring reagent to determine the concentration of the sample.
   化学分析师使用滴定试剂来确定样本的浓度。
3. 3. The pfeilring reagent was carefully prepared and stored according tothe manufacturer's instructions.
   滴定试剂被小心地制备并按照制造商的指示储存。