This method is based on the colorimetric reaction of nitro‑PAPS with Zn²⁺ in alkaline solution to form a purple complex, which exhibits a characteristic absorption peak at 570 nm. Interfering ions such as Cu²⁺ and Fe³⁺ in the reaction system can be effectively masked by adjusting the pH and adding a chelating agent.
危险品化学品经营许可证（带存储）