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Journal of Radioanalytical and Nuclear Chemistry

, Volume 306, Issue 3, pp 611–616 | Cite as

Spatial distribution of neutron flux in geological larger sample analysis at CDTN/CNEN, Brazil

  • Maria Ângela de B. C. Menezes
  • Radojko Jaćimović
  • Claubia Pereira
Article

Abstract

Iron monitor wire was used to evaluate the neutron flux gradients inside 5 g-geological sample during irradiation. The spatial distribution for thermal flux was about 2 %/cm for radial and axial gradients and about 5 %/cm for radial and 2.5 %/cm for axial gradients for fast neutrons. The results were evaluated using reference material IAEA-SOIL-7 analysed as small and larger samples and tested with calculating E n numbers. This test pointed out that all results were consistent within a 95 % confidence interval. The contribution of the neutron flux gradients may be reduced for larger sample using the standard procedure of the k 0-instrumental neutron activation analysis.

Keywords

Neutron activation analysis k0-instrumental neutron activation analysis Larger sample Neutron flux gradients 

Notes

Acknowledgments

This work was partially supported by the International Atomic Energy Agency under Grant BRA-14798, by the Foundation for Research Support of Minas Gerais, FAPEMIG, under Grant APQ-01259-09 and by financial support from the Slovenian Research Agency (ARRS) through programme P1-0143.

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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2015

Authors and Affiliations

  • Maria Ângela de B. C. Menezes
    • 1
    • 3
  • Radojko Jaćimović
    • 2
  • Claubia Pereira
    • 3
  1. 1.Nuclear Technology Development Centre, Brazilian Commission for Nuclear Energy, CDTN/CNEN, Division for Reactor and Analytical Techniques, Laboratory for Neutron Activation AnalysisBelo HorizonteBrazil
  2. 2.Department of Environmental Sciences, Jožef Stefan InstituteLjubljanaSlovenia
  3. 3.Department of Nuclear Engineering, Engineering School, DEN/UFMGFederal University of Minas GeraisBelo HorizonteBrazil

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