GB/T 4 2342.2-2023 Photoelectric centrifugation in liquid phase centrifugal sedimentation method focusing on the determination of Particle size distribution. It specifies the scope of application and principle of the method, specifies the requirements of instruments and equipment, and covers the parameters of photoelectric centrifuges. Introduce sample prepative, test process, including solution configuration, centrifugal operation and data collection analysis. This standard provides a unified specification for accurate determination of Particle size distribution, and helps scientific research, production and other fields to accurately grasp particle size information, which is of great significance to material research and development, quality control and other work.