A method for dating small amounts of uranium

作者：Pointurier Fabien^*; Hubert Amelie; Roger Gaelle

来源：Journal of Radioanalytical and Nuclear Chemistry, 2013, 296(2): 593-598.

DOI：10.1007/s10967-012-2198-8

• Radiochronometry
• Dating
• Thorium-230
• Uranium
• Microchemistry
• Forensics

In this study we describe a method for uranium dating (i.e. determination of the date of the last chemical purification undergone by the material) by measurement of the Th-230/U-234 ratio, applicable to sub-microgram quantities. The chosen protocol (AG1x8 resin in hydrochloric acid medium) has been tested on separation microcolumns (100 mu l). This 'microchemistry' technique considerably limits the risks of contamination by reagents or the environment. Thorium extraction efficiencies were greater than 90 % and reproducible. The quantities of Th-230 introduced by the chemical purification procedure were negligible. Using an ultra-sensitive inductively coupled plasma mass spectrometry measurement technique, detection limits of the order of femtograms (10(-15) g) of Th-230 were obtained. The complete procedure, chemical separation and isotope measurement, was successfully tested and validated on a few micrograms of uranium.

• 出版日期2013-5
• 单位中国地震局