1. Institute of Chemical Physics, University of Latvia, Jelgavas Iela 1, LV-1004 Riga, Latvia
2. Faculty of Chemistry, University of Latvia, Jelgavas Iela 1, LV-1004 Riga, Latvia
3. Institute of Solid State Physics, University of Latvia, Kengaraga Iela 8, LV-1063 Riga, Latvia
4. Baltic Scientific Instruments, Ganibu Dambis 26, LV-1005 Riga, Latvia
5. Institute of Food Safety, Animal Health and Environment “BIOR”, Lejupes Iela 3, LV-1076 Riga, Latvia
6. Centre for Radiation Research and Technology, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw, Poland