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Journal of Radioanalytical and Nuclear Chemistry
Authors:
O. Díaz Rizo
,
M. Manso Guevara
,
E. Herrera Peraza
,
I. Alvarez Pellón
, and
M. López Reyes

Abstract  

Using the facilities of the Triga Mark III reactor at the NNRI, Mexico and the HAV-1 multipurpose monitor, the reactor power dependency for thek 0-standardization essential neutron flux parameters as: epithermal shape factor (), thermal to epithermal ratio (f) and neutron temperature (T n ) were experimentally obtained. Evaluation of the obtained dependencies shows that it is unnecessary to analyze the possible introduction of correction factors in thek 0-INAA experimental results. A single experimental procedure to determine throughf is suggested.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
O. Rizo
,
E. Herrera Peraza
,
M. Manso Guevara
,
I. Pellón
,
M. López Reyes
,
M. Cabrera
, and
M. Montero Cabrera

Abstract  

The main results obtained during the characterization of the Triga Mark III reactor at NNRI, Salazar, Mexico, the development of the nonconventional multimonitor HAV-1, the use of Certified Reference Material (CRM) as multimonitor fork 0-factors experimental determination, and to study the reactor power and slowing-down thickness dependencies of the reactor flux parameters and its influence ink 0-INAA are presented. The experience of thek 0-INAA group at ISCTN, in the application of this analytical technique for different purposes is resumed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
O. Díaz Rizo
,
M. Manso Guevara
,
E. Herrera Peraza
,
I. Alvarez Pellón
,
M. López Reyes
,
D. López Aldana
, and
F. Garcia Yip

Abstract  

The experimental dependence of the α,f andT n parameters, in function of the water thickness, for different irradiation channels of Triga Mark III reactor, were analyzed. An exponential law for the α(r) dependence was obtained in the neighborhood of the active zone of the reactor numerically modelated using theS n method for 69 neutrons groups, and this dependence is slower in light water reactors than in graphite reactors.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Gelen
,
N. López
,
O. D. Maslov
,
A. G. Belov
,
M. V. Gustova
,
O. Díaz
,
J. Beltrán
,
J. Soto
,
M. V. Manso Guevara
,
M. Pérez
, and
M. J. Simón

Summary  

Twenty six elements was studied preliminary in the superficial sediments of Havana Bay using gamma activation analysis by the electron accelerator microtron MT-25 at the Flerov Laboratory of Nuclear Reactions, JINR. Samples from five zones of Havana Bay including the three coves were analyzed. The obtained results show a close relation between the concentration levels of the studied elements and the pollution sources. Some elements (As, Ba, Ni, Pb, Cu, Zn, Fe, Cr, Mn) have high concentration levels compared to the values for other environmental marine sediments reported in the literature.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. D. T. Arruda-Neto
,
A. C. Cestari
,
C. B. Zamboni
,
M. Saiki
,
G. P. Nogueira
,
L. E. C. Fonseca
,
M. V. Manso-Guevara
,
A. Deppman
,
V. P. Likhachev
,
J. Mesa
,
O. A. M. Helene
,
S. A. C. Jorge
,
M. N. Martins
,
A. N. Gouveia
,
O. Rodriguez
,
F. Guzmán
, and
F. Garcia

Summary  

Neutron activation analysis has been used to study uranium incorporation in poultry bones as function of chow doped with: (a) uranium (20 ppm); (b) U-doped food (20 ppm) plus phytase (120 ppm) and (c) U-doped food (20 ppm) plus phytase (180 ppm). To investigate this situation experiments involving several groups of Cobb broilers was performed. Two animals per group were sacrificed weekly up to their adultness and uranium concentration in the tibia was measured. It was observed that the concentration of uranium (µg U/g bone) is decreasing all along the animal life spanning period of 14-42 days. This behavior suggests that the skeleton mass is growing faster than the corresponding accumulation of uranium. The administration of phytase seems not to alter this scenario.

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