放射性核素的衰变率,特别是发生轨道电子俘获的衰变率与核外电子密度密切相关,改变核外的物理、化学环境就可能改变核外电子密度,从而影响这些核素的衰变率[1-4]。精确测量这些核素的衰变率以及研究它们在不同核外环境中衰变率的变化在许多领域有着重要的应用,例如核物理、 The decay rate of radionuclides, especially the decay rate of orbital electron capture, is closely related to the electron density outside the nucleus. Changing the physical and chemical environment outside the nucleus may change the electron density outside the nucleus, thus affecting the decay rate of these radionuclides [1 -4]. The accurate measurement of the decay rates of these nuclides and the study of their changes in decay rates in different extranuclear environments have important applications in many fields such as nuclear physics,