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Instrumental Neutron Activation Analysis (INAA). F rank L aboratory of N eutron P hysics Summer school in Dubna 5.7.-25.7.2010 Prepared by: B. Andel (SVK) , E. Govor (BLR), K. V. Mareš (CZE), M. Mazánová (SVK), A. Moravcsík (SVK), V. Voronova (BLR) Supervisor :
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InstrumentalNeutronActivationAnalysis (INAA) Frank Laboratory of Neutron Physics Summer school in Dubna 5.7.-25.7.2010 Prepared by: B. Andel (SVK), E. Govor (BLR), K. V. Mareš (CZE), M. Mazánová (SVK), A. Moravcsík (SVK), V. Voronova (BLR) Supervisor : prof. M. V. Frontasyeva, FLNP
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)
Forms of NAA • Destructive ( radiochemical ) -theresulting radioactive sample ischemicallydecomposed, and the elementsare chemically separated • Nondestructive(instrumental ) -the resulting radioactive sample iskept intact
Detection • Irradiated samples are analyzed by gamma-spectrometry
Neutron sources • Isotopic neutron sources (252Cf, 242Am) • Neutron generators • Nuclear reactors • At FLNP the pulsed fast reactor IBR-2 is used
Neutrons • Thermal 0.025 eV-0.5 eV • Epithermal 0.5 eV-100 keV • Fast 100 keV-25 MeV
Characteristics of INAA • Non-destructive analysis • The chemical formand physical state of theelements donot influence the activation anddecayprocess • Multi-element analytical technique • C, H, N, O and Sido not activate well • Suitable even for determination of masses in the order of 10–6–10–9 g and less
Applications of INAA at FLNP • Environmental studies (migration of pollutants in ecosystems, air pollution studies using moss-biomonitors) • Biotechnology for medicine (development of new pharmaceuticals and sorbents) • Material Science (high purity materials, nanoparticles and objects of national heritage)
Dependence of counts on distance between detector and gamma-source
References • 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
Foto by Kamil Vavrinec Mares Thank you for your attention