为了提高钼兰法测定磷的稳定性。我们试验在磷钼黄被还原之前加入阿拉伯树胶,效果很好。还原后的磷钼兰色泽可稳定20分钟以上。阿拉伯树胶的加入量即使勿严加控制,对结果也无显著影响。但加入量过少,磷钼兰的色泽稳定时间短。本法采取加1%的阿拉伯树胶5毫升。 In order to improve the molybdenum blue method to determine the stability of phosphorus. We experimented with adding gum arabic before the phosphomolybdenum yellow was reduced, which worked well. The phosphomolybdenum color after reduction can be stable for more than 20 minutes. The amount of gum arabic added, even without serious control, had no significant effect on the results. However, adding too little, phosphorus molybdenum blue color stability time is short. The law to take plus 1% gum acacia 5 ml.