Neutron activation analysis of Tibetan traditional medicinal pills at the VR-1 training reactor

Abstract

The nuclear analytical methods provide the research techniques usually used in hard sciences such as physics, chemistry, engineering and technology, or natural sciences and technology, but it is very rare to use them in social sciences and humanities. The Czech Technical University (CTU) in Prague operates the VR-1 training reactor primarily focused on training students, nuclear engineering, reactor physics, and research; however, the utilization of this nuclear reactor has also been extended to humanities in recent years. In this direction, the research activities carried out at the reactor include the investigation of historical artefacts and testing of pharmaceutical and food industry samples. This contribution deals with the detailed study of traditional Tibetan medicinal pills by means of instrumental neutron activation analysis (NAA) at the VR-1 nuclear reactor. Three various kinds of Tibetan pills were irradiated by thermal neutrons (ϕ=2×109cm−2s−1) in the experimental vertical channel at maximum reactor power (80 W), and irradiated samples were analysed using the semiconductor HPGe detector; saturated activities were obtained by means of the nuclear gamma-ray spectrometry, and subsequently the composition of the pills was determined (qualitative and quantitative analysis). The presence of Au, K, Fe, Na, As, Sr, Sb, and Hg was revealed in studied samples. The results presented in this paper show clearly that the low-power research reactor VR-1 is excellent tool for the neutron activation analysis experiments.