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Abstract  

The behaviour of Si implanted with high doses of P and Ar (5·1014 to 1017 cm−2) in HF solutions was investigated using radioactive isotopes. The reaction products were analyzed by ion exchange and electrochemical polarization. An increased dissolution was found and a possible reaction mechanism given.

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Abstract  

The IAEA's Marine Environment Laboratory has been assisting laboratories in Analytical Quality Control Services (AQCS) for the analysis of radionuclides in the marine environment since the early seventies. AQCS through world-wide and regional intercomparison exercises and the provision of reference methods and reference materials (RM) have been recognized as an important component of quality assurance/quality control. A total of 43 intercomparison exercises were organized and 37 RM were produced for marine radioactivity studies. All important marine matrices were covered, e.g., seawater, marine sediments of different chemical compositions, fish, shellfish and seaplants. RM were prepared from samples collected at contaminated sites (e.g., the Irish Sea, the Baltic Sea, the Arabian Sea, Mururoa and Bikini Atolls, etc.) as well as from sites affected only by global fallout (e.g., the Pacific Ocean). Available RM are listed in the IAEA biennial catalogue and can be purchased at a minimal price. An overview of prepared RM for radionuclides in marine matrices is presented and discussed in more detail.

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Abstract  

Irrigation of rice plants with a solution of rare earth elements increases both the production capacity and the resistance to disease. Assuming that the treated plants remain expendable, the different parts of plants, root stalk and grain, were analyzed by instrumental neutron activation analysis (INAA) and by mass spectrometry after plasma excitation (ICP-MS). About 40 elements were determined. The results showed that the contamination remained in the roots and was absent in rice grains. The analytical distribution of different elements in different parts of both treated and non-treated plants has given some information conceming the possible effect of the rare earth treatment. The performances of the two analytical methods have been compared.

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Abstract  

Radionuclides in aerosols and precipitation have been analyzed by IAEA-MEL in Monaco since 1987 and 1999, respectively, to identify their behavior in the atmosphere and delivery into the northwestern Mediterranean Sea. While the concentration of 7Be in aerosols has been affected by the stratospheric-tropospheric mixing and precipitation, the concentration of 137Cs in aerosols has been influenced by a combination of local meteorological conditions and re-suspension of 137Cs from soil. Higher concentrations of 7Be, 137Cs, 239,240Pu and 241Am in precipitation occurred during spring and summer. The highest deposition rates of these radionuclides were observed in spring and autumn during periods of high precipitation. A good correlation was found between the amount of precipitation and depositional flux for 7Be, but not for 137Cs, 239,240Pu and 241Am. This indicates that the wet process as well as the dry process seem to be important factors in determining the annual deposition for transuranic radionuclides and 137Cs.

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Periodica Mathematica Hungarica
Authors:
M. Szalay
,
I. Szalay
,
A. Fialowski
,
Pham Ánh
,
Á. Bosznay
, and
T. Matolcsi
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Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Pham
,
M. Betti
,
P. Povinec
,
V. Alfimov
,
D. Biddulph
,
J. Gastaud
,
W. Kieser
,
J. López Gutiérrez
,
G. Possnert
,
J. Sanchez-Cabeza
, and
T. Suzuki

Abstract  

A certified reference material designed for the determination of 129I in seawater, IAEA-418 (Mediterranean Sea water) is described and the results of certification are presented. The median of 129I concentration with 95% confidence interval was chosen as the most reliable estimates of the true value. The median, given as the certified value, is 2.28 × 108 atom L−1 (95% confidence interval is (2.16–2.73) 108 atom L−1), or 3.19 × 10−7 Bq L−1 (95% confidence interval is (3.02–3.82) × 10−7 Bq L−1). The material is intended to be used for standardization procedures applied in accelerator mass spectrometric laboratories. It is available in 1 L units and may be ordered via IAEA web side (www.iaea.org).

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Pham
,
M. Betti
,
P. Povinec
,
M. Benmansour
,
R. Bojanowski
,
P. Bouisset
,
E. Calvo
,
G. Ham
,
E. Holm
,
M. Hult
,
C. Ilchmann
,
M. Kloster
,
G. Kanisch
,
M. Köhler
,
J. La Rosa
,
F. Legarda
,
M. Llauradó
,
A. Nourredine
,
J.-S. Oh
,
M. Pellicciari
,
U. Rieth
,
A. Rodriguez y Baena
,
J. Sanchez-Cabeza
,
H. Satake
,
J. Schikowski
,
M. Takeishi
,
H. Thébault
, and
Z. Varga

Abstract  

A new Reference Material (RM) for radionuclides in mussel (Mytilus galloprovincialis) from the Mediterranean Sea (IAEA-437) is described and the results of the certification process are presented. Four radionuclides (40K, 234U, 238U, and 239+240Pu) have been certified, and information values on massic activities with 95% confidence intervals are given for nine radionuclides (137Cs, 210Pb(210Po), 226Ra, 228Ra, 228Th, 230Th, 232Th, 235U, and 241Am). Results for less frequently reported radionuclides (90Sr, 129I, 238Pu, 239Pu, and 240Pu) are also reported. The RM can be used for quality assurance/quality control of the analysis of radionuclides in mussel samples, for the development and validation of analytical methods and for training purposes. The material is available in 200 g units.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Pham
,
M. Betti
,
P. Povinec
,
M. Benmansour
,
V. Bünger
,
J. Drefvelin
,
C. Engeler
,
J. Flemal
,
C. Gascó
,
J. Guillevic
,
R. Gurriaran
,
M. Groening
,
J. Happel
,
J. Herrmann
,
S. Klemola
,
M. Kloster
,
G. Kanisch
,
K. Leonard
,
S. Long
,
S. Nielsen
,
J.-S. Oh
,
P. Rieth
,
I. Östergren
,
H. Pettersson
,
N. Pinhao
,
L. Pujol
,
K. Sato
,
J. Schikowski
,
Z. Varga
,
V. Vartti
, and
J. Zheng

Abstract  

A new certified reference material (CRM) for radionuclides in sea water from the Irish sea (IAEA-443) is described and the results of the certification process are presented. Ten radionuclides (3H, 40K, 90Sr, 137Cs, 234U, 235U, 238U, 238Pu, 239+240Pu and 241Am) have been certified, and information values on massic activities with 95% confidence intervals are given for four radionuclides (230Th, 232Th, 239Pu and 240Pu). Results for less frequently reported radionuclides (99Tc, 228Th, 237Np and 241Pu) are also reported. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in water samples, for the development and validation of analytical methods and for training purposes. The material is available in 5 L units from IAEA (http://nucleus.iaea.org/rpst/index.htm).

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
P. Povinec
,
M. Pham
,
J. Sanchez-Cabeza
,
G. Barci-Funel
,
R. Bojanowski
,
T. Boshkova
,
W. Burnett
,
F. Carvalho
,
B. Chapeyron
,
I. Cunha
,
H. Dahlgaard
,
N. Galabov
,
L. Fifield
,
J. Gastaud
,
J. Geering
,
I. Gomez
,
N. Green
,
T. Hamilton
,
F. Ibanez
,
M. Ibn Majah
,
M. John
,
G. Kanisch
,
T. Kenna
,
M. Kloster
,
M. Korun
,
L. Liong Wee Kwong
,
J. La Rosa
,
S. Lee
,
I. Levy-Palomo
,
M. Malatova
,
Y. Maruo
,
P. Mitchell
,
I. Murciano
,
R. Nelson
,
A. Nouredine
,
J. Oh
,
B. Oregioni
,
G. Le Petit
,
H. Pettersson
,
A. Reineking
,
P. Smedley
,
A. Suckow
,
T. van der Struijs
,
P. Voors
,
K. Yoshimizu
, and
E. Wyse

Abstract  

A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units.

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