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INSTRUMENTAN NEUTRON ACTIVATION ANALYSIS (INAA) FRANK LABORATORY OF NEUTRON PHYSICS SUMMER PRACTICE, 05-23 September 2011 JINR-DUBNA. Prepared by:
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INSTRUMENTAN NEUTRON ACTIVATION ANALYSIS (INAA)FRANK LABORATORY OF NEUTRON PHYSICS SUMMER PRACTICE, 05-23 September 2011 JINR-DUBNA Prepared by: Tshepo Motimedi (NWU), Happy Vilakazi (UJ), Kefilwe Thoane (NWU), Ntombizikhona. B Ndlovu (SU), Darya Adamchyk(BLR), Tatsiana Lapatsentava(BLR), Alexandr Petrov (BLR), Elena Govor (BLR) Supervisor: Prof M. V. Frontasyeva. (FLNP)
Contents • Introduction. • INAA Technique • Sample Preparations • Analytical Technique and practical's • γ-Spectroscopy • Summary • Applications of INAA • References
Founder of FLNP FRANK LABORATORY OF NEUTRON PHYSICS JOINT INSTITUTE FOR NUCLEAR RESEARCH 1956 • Ilґja Mikhailovich Frank (1908-1990) • The Nobel Prize winner in Physics
Introduction • Neutron Activation Analysis (NAA) is a sensitive multi-element analytical technique used for both qualitative and quantitative analysis of major, minor, trace and rare elements • NAA was discovered in 1936 by G. Hevesy (Hungary) and H. Levi (Denmark)
Method for NAA • Destructive (Radiochemical), the elements of the resulting radioactive sample undergoes decomposition and chemical separation process. • Non Destructive (Instrumental), chemical separation is not performed, and therefore the resulting radioactive sample is not decomposed to elemental fragments.
Neutron source • IBR-2 Pulsed Fast Reactor
INAA Procedure Sample preparation . . Neutron irradiation of samples Decay of radioactivity Decay periods between 15s – 7 days Decay time Measurement of γ-ray spectra of samples and standards with HPGe-detector Count time Evaluation of the γ-ray spectra using a computer program Calculation of element content giving results in µg/g
Samples • Al encapsulation, long irradiation • Encapsulation in special designed bags, short irradiation
X-section of Cd-113 Cd cut-off
γ- Spectroscopy Detector Detector Calibration
Applications of INAA at IBR-2 Life Sciences Material Sciences • Biotechnologies: development of new pharmaceuticals, cleaning the environment from toxic elements (biosorption) and synthesis of nanoparticles • NAA for the technological process of synthesis of diamonds and NB (boron nitride) • Analysis of archaeological and museum objects from Russian and other countries • NAA for decommissioning of Nuclear Power Plants and utilization of industrial wastes • Biomonitoring of atmospheric depositionof heavy metals and other elements (Project REGATA) • Control of quality and safety of foodstuffs, grown in industrially contaminated areas of RF and South Africa (grant of SA) • Assessment of different ecosystems and their impact on human health
Conclusion • Neutron Activation Analysis (NAA) is a useful method for the simultaneous determination of major, minor and trace elements of geological, environmental and biological samples in ppb-ppm range with or without chemical separation.
Reference • P. Bode: Instrumental and organizational aspects of a neutron activation analysis laboratoty • http://www.sciner.com/Neutron/naa.html • http://reactor.engr.wisc.edu/naa/ • http://tin.er.usgs.gov/geochem/doc/inaa.htm • http://reactor.engr.wisc.edu/naa/UWNRNAA.htm • http://www.reak.bme.hu/Wigner_Course/WignerManuals/Budapest/NEUTRON_ACTIVATION_ANALYSIS.htm • http://archaeometry.missouri.edu/naa_overview.html