Instrumental Neutron Activation Analysis (INAA)
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Transcript Instrumental Neutron Activation Analysis (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
The founders of 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 ) - the resulting radioactive
sample is chemically decomposed, and the elements are
chemically separated
Nondestructive ( instrumental ) - the resulting
radioactive sample is kept intact
Principle
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 form and physical state of the elements do
not influence the activation and decay process
Multi-element analytical technique
C, H, N, O and Si do 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
24000
1600
22500
152
1500
Eu 121,8keV
152
Eu 1408keV
1400
19500
1300
18000
1200
counts in peak (time 7 min)
counts in peak (time 7 min)
21000
16500
15000
13500
12000
10500
9000
7500
6000
4500
1100
1000
900
800
700
600
500
400
300
200
3000
100
4
5
6
7
8
9
10
11
distance (cm)
12
13
14
15
16
0
4
5
6
7
8
9
10
11
distance (cm)
12
13
14
15
16
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