liquid interface indicator

例句：

1. 1. The liquid interface indicator isused to detect the presence of air bubbles in the oil.
   液态界面指示器用于检测油中是否存在气泡。
2. 2. The liquidinterface indicator was used to monitor the qualityof the oil during the production process.
   液态界面指示器用于监控生产过程中油的质量。
3. 3.The liquid interface indicator can be used toidentify the type of fluid being tested.
   液态界面指示器可用于识别正在测试的流体类型。