Williams C C, Kereiakes J G, Grossman L W
Radiology. 1981 Feb;138(2):445-8. doi: 10.1148/radiology.138.2.7455128.
A study was performed to determine the accuracy of 99Mo measurements using three commercial dose calibrators with their 99Mo assay shields. One 99Mo assay shield allowed excessive penetration by the lower energy 99mtc photons, resulting in the calibrator's falsely high interpretation of the activity of 99Mo present in the high-activity 99mTc eluates. All three calibrators performed adequately with a National Bureau of Standards 99Mo standard in equilibrum with 99mTc. By using low-activity aliquots of 99Mo and 99mTc, a low-level linearity test was performed. Two of the calibrators were found to have a threshold of approximately 10 microCi (370 kBq) for a nonzero 99Mo response, although one of these occasionally produced variable nonzero responses below its threshold. Only one of the calibrators was found to reflect accurately the activity of 99Mo present under all conditions tested.
进行了一项研究，以确定使用三种配备99Mo分析屏蔽的商用剂量校准器测量99Mo的准确性。一个99Mo分析屏蔽允许较低能量的99mTc光子过度穿透，导致校准器对高活度99mTc洗脱液中存在的99Mo活度做出错误的高读数。在与99mTc处于平衡状态的国家标准局99Mo标准下，所有三种校准器的表现都足够好。通过使用低活度的99Mo和99mTc等分试样，进行了低水平线性测试。发现其中两个校准器对于非零99Mo响应的阈值约为10微居里（370 kBq），尽管其中一个偶尔在其阈值以下产生可变的非零响应。在所有测试条件下，仅发现一个校准器能准确反映存在的99Mo活度。
