Figure 6

(a) The SEM analysis of raspberry-shape morphology for PS/PPO microspheres. (b) The emission spectrum of PPO and PS/PPO microspheres. (c) The LSC signal of 40K (14.4 Bq/g) measured by liquid scntillation counter with PS hollow microspheres, PS/PPO microspheres and water solution, where the measured time was 5 minutes.