A two-phase separation mixed solution can undergo phase separation from one phase to two phases (i.e., upper and lower phases) in a batch vessel in response to changes in temperature and/or pressure. This phase separation is reversible. When the mixed solution undergoes a phase change while being fed into a microspace region, a dynamic liquid-liquid interface is formed, leading to a multiphase structure. This flow is called a phase-separation multiphase flow. Annular flow in a microspace, which is one such phase-separation multiphase flow, is interesting and has been applied to chromatography, extraction, reaction fields, and mixing. Here, research papers related to phase-separation multiphase flows-ranging from the discovery of the phenomenon to basic and technical research from the viewpoint of analytical science-are reviewed. In addition, the development of a new separation mode in a high-performance liquid chromatography system based on phase-separation multiphase flow is introduced.

中文翻译：

---

相分离多相流：在分析化学中的初步应用。

两相分离混合溶液可以响应于温度和/或压力的变化而在间歇容器中经历从一相到两相（即，上相和下相）的相分离。这种相分离是可逆的。当混合溶液在进入微空间区域时发生相变时，会形成动态液-液界面，从而形成多相结构。这种流动称为相分离多相流。微空间中的环形流是一种相分离多相流，它很有趣，已应用于色谱、萃取、反应领域和混合。在此，综述了与相分离多相流相关的研究论文——从现象的发现到从分析科学的角度进行的基础和技术研究。此外，还介绍了基于相分离多相流的高效液相色谱系统中新型分离模式的发展。