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~3H 和~(14)C 等软β发射体的测量仪器液体闪烁计数器早已被开发出来并使用了。这种仪器的主要优点不仅是测量时没有自吸收,而且射线入射到闪烁体之前也没有吸收,因为这是一种液体闪烁体所特有的内部样品测最。已经建立了~3H和~(14)C 放射分析的外标准道比和样品道比技术。这些淬灭校正技术需要一组~3H或~(14)C 淬灭标准源。另一方面,这些淬灭校正技术对~3H和~(14)C以外的其它核素的常规放射性分析并不很适用,因为制备各别的淬灭标准源是费事和费时的。应用4πβ-γ符合计数,已把效率示踪技术应用于β-发射体的放射分析,而且也把这种技术成功地应用于液体闪烁测量。“效率示踪技术”一词是指对应于参考示踪剂的计数效率来绘制被测样品的计数效率图。液体闪烁技术中的样品制备比4πβ-γ符合技术中的容易
~ 3H and ~ (14) C and other soft beta emitters measuring instruments liquid scintillation counter has long been developed and used. The main advantages of this instrument are not only the absence of self-absorption during the measurement, but also the absorption of the radiation before it enters the scintillator as this is the internal sample characteristic of a liquid scintillator. External standard ratio and sample DAI techniques for ~ 3H and ~ (14) C emission analyzes have been established. These quench correction techniques require a set of ~ 3H or ~ (14) C quench standard sources. On the other hand, these quench-correction techniques are not well suited for routine radioactive analyzes of ~ 3H and ~ (14) C nuclides, as preparing separate quench standards is cumbersome and time-consuming. Using 4πβ-γ coincidence counting, efficiency tracing techniques have been applied to the emission analysis of β-emitters and this technique has also been successfully applied to liquid scintillation measurements. The term “efficiency tracing technique” refers to plotting the counting efficiency of a test sample corresponding to the counting efficiency of a reference tracer. The sample preparation in liquid scintillation technology is easier than in the technology conforming to 4πβ-γ