测量了两个4πβ正比计数管的γ灵敏度。对于小计数管的多数γ灵敏度与William和Compion的值相当好地符合。 测量了13个~(60)Co源的活度,活度范围从6到180kBq。用Cox-Isham公式计算活度,洁度范围从6到110kBq得到的结果很好地符合。剩余结果的差别是由于β和γ道之间的匹配不很完善以及死时间修正所引起的。 The γ sensitivity of two 4πβ proportional counters was measured. The majority of γ-sensitivity for small-count tubes fits well with the values ​​of William and Compion. The activities of 13 ~ (60) Co sources were measured from 6 to 180kBq. The activity was calculated using the Cox-Isham formula, and the cleanliness ranged from 6 to 110kBq. The results were well fitted. The difference between the remaining results is due to the poor matching between β and γ tracks and the correction of dead time.