描述用闪烁探测器测量轻水反应堆一回路水中的放射性核素１３Ｎ浓度的原理、方法及在几种不同功率水平下１３Ｎ浓度的实验测量值。测量值的总不确定度为１０％。 Describe the principle, method, and experimental measurements of 13N concentrations at several different power levels using a scintillation detector to measure radionuclide 13N concentrations in the primary loop water of a light water reactor. The total uncertainty of the measurement is 10%.