Search results for "Strontium-90"
showing 4 items of 4 documents
Strontium90 for determination of time since death
1999
Strontium90 (Sr90) is an artificial nuclear fission product of the atmospheric a-bomb testing between 1945 and 1979. It was spread throughout the atmosphere in the following years. Sr90 is an analogue to calcium and therefore enriched in human bones. Several studies especially in the 1960s and 1970s were undertaken to investigate the Sr90 burden and the resulting incorporated radiation in humans, but present studies are missing. In this study nine bone samples, three from 1931/32 and six from 1989 to 1994 were examined by measuring the Sr90 radiation. The samples from 1931/32 did not show any Sr90 activity. All the samples from 1989 and later showed a Sr90 activity, but the intensity was ve…
Ultratrace analysis and isotope ratio measurements of long-lived radioisotopes by resonance ionization mass spectrometry (RIMS).
2003
Resonance Ionization Mass Spectrometry (RIMS) is a sensitive and selective method for ultratrace analysis of long-lived radioisotopes and isotope ratio measurements. It provides extremely high isobaric suppression and good overall efficiency. The experimental limits of detection are as low as 10(6) atoms per sample and isotopic selectivities of 5x10(12) have been obtained. The widespread potential of RIMS, using different experimental arrangements, is demonstrated for the determination of the radiotoxic isotopes Pu-238 to Pu-244 and Sr-89/Sr-90 in various environmental samples as well as for Ca-41 in nuclear reactor components and biomedical samples.
Quantitative Detection of Strontium-90 and Strontium-89 in Environmental Samples by Laser Mass Spectrometry
1990
Parallel to the strongly growing public concern about environmental problems, new ideas for trace detection and analysis of toxic and radioactive material are being developed. One of these new and outstanding experimental techniques is the application of analytical laser spectroscopy. Most interesting in this context is the method of resonance ionization spectroscopy (RIS), as proposed1 already in 1972 combining very high sensitivity in the detection of the element or isotope under investigation with high selectivity in the suppression of contaminants2–4.
Natural and artificial radioactivity levels in Livingston Island (Antarctic regions).
1994
Radioactive contamination of the sea and land is due, on the one hand, to fallout from atmospheric atomic explosions since 1945, and, on the other, to emissions produced by nuclear and radioactive facilities. Given its geographic position far distant from the aforementioned main sources of radioactive contamination, Antarctica should have the lowest levels that can be measured on the Earth of artificial radionuclides in the various receptor media which are characteristic of the trophic chain. In the case of Antarctica, these are melt-water, sea-water, mosses, algae, and lichens. With the aim of contributing basic information on the radiation levels present in the Antarctic ecosystem, we hav…