acid-base indicator

1. Unsized paper treated with litmus for use as an acid-base indicator.
   未定尺寸经石蕊处理的纸，用作酸碱显示剂。
2. A white or pale yellow crystalline powder, C20H14O4, used as an acid-base indicator, in making dyes, and in medicine as a laxative.
   一种白色或淡黄色的晶体粉末，C20H14O4，用作酸性指示剂，用于制染料，并在医学上用作一种轻泻剂。
3. A coloring material that turns red in acid solutions and blue in alkaline solutions; used as an acid-base indicator.
   一种在酸性溶液中变红、在碱性溶液中变蓝的染色材料，亦作酸碱显示剂。
4. A study of the application of Victoria Blue B as acid-base indicator
   维多利亚蓝B作为酸碱指示剂的应用研究
5. This reagent is a good acid-base indicator and colour reagent for metallic ions.
   本试剂是一个好的酸指示剂和金属离子显色剂。
6. Preparation of Alternate Acid-Base Indicator by Using Plant Pigment
   用植物色素制取代用酸碱指示剂

noun

1. an indicator that changes color on going from acidic to basic solutions