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Abstract  

An effective method to minimize the presence of141Ce in the final hexahydrated uranyl nitrate recovery product has been obtained. This condition is considered as one prepurification stage in the recovery process of residual nonfissioned uranium in the production of99Mo of fission.

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Journal of Thermal Analysis and Calorimetry
Authors:
C. Auguet
,
J. Lerchner
,
P. Marinelli
,
F. Martorell
,
M. Rodriguez de Rivera
,
V. Torra
, and
G. Wolf

Abstract  

The experimental analysis of conventional conduction calorimeters shows excellent reproducibility and relevant systematic errors in comparison with thermodynamic values established via adiabatic calorimeters. Two examples: a DSC and a liquid flow device are schematically analyzed. When an increased accuracy will be obtained the positional effects on the experimental set-up and on the measurement process need to be modelled. From experimental measurements realized on the Xensor liquid nano-calorimeter representative models can be built. To evaluate the reliability of measurement routines, established from experimental basis, several different dissipation structures inside the working space can be simulated. Two experimental configurations related to drop to drop reaction and to continuous mixing are modelled via RC approach. The RC formalism is extended to evaluate the carried energy effect produced by the continuous inflow/outflow of reactants in the mixing enthalpy chamber.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
G. Ferro-Flores
,
C. Arteaga de Murphy
,
P. Palomares-Rodríguez
,
L. Meléndez-Alafort
, and
M. Pedraza-López

Summary  

The ubiquicidin 29-41 fragment (UBI) is a cationic antimicrobial peptide. The aim of this study was to develop an instant kit formulation for the preparation of 99mTc-UBI 29-41 in high radiochemical yield and to evaluate its use as an infection imaging agent in humans. The components were selected to produce a direct 99mTc labeling, presumably to the amine groups of Lys and Arg7. 99mTc-UBI 29-41 obtained from the lyophilized kit showed radiochemical purity of >97% with an average target/non-target ratio of 2.3±0.6 in positive infection sites at 2 hours. Kits were stable at 4 °C for over 6 months.

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Acta Physiologica Hungarica
Authors:
A. Lemberg
,
M. Fernández
,
G. Ouviña
,
R. Rodríguez
,
H. Peredo
,
C. Susemihl
,
I. Villarreal
, and
E. Filinger

The hypothesis of the present study was that diabetes mellitus might affect brain metabolism. Streptozotocin (STZ)-induced diabetic rats, treated with vanadyl sulphate (V) and sodium tungstate (T) were employed to observe the aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatine kinase (CK) activities in brain homogenates. Significant increases in AST, ALT and CK activities were found in diabetic brain homogenates against controls, suggesting increments of transamination in brain and/or increases in cell membrane permeability to these enzymes. The increase in brain CK possibly expresses alterations in energy production. The decrease in CK activity caused by V and T treatment in diabetic rats suggests that both agents tend to normalize energy consumption. It is also possible that V and T-induced hypoglycemic effects cause metabolic alterations in brain.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
G. Capote Rodriguez
,
R. Padilla Alvarez
,
G. Pérez Zayas
,
A. Hernández Rivero
,
M. López Reyes
,
S. Ribeiro Guevara
, and
J. Molina Insfrán

Abstract  

Thirty elements were determined by INAA in Cuban soil samples collected in 17 zones from western regions of Cuba, which were affected by neuropathy epidemic in 1992. The presence of toxic elements was evaluated to provide data for the analysis of possible paths of intoxication through local agriculture product consumption. The results obtained for As, Th and U are compared with similar data reported on literature.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
F. Poineau
,
E. Rodriguez
,
P. Weck
,
A. Sattelberger
,
P. Forster
,
T. Hartmann
,
E. Mausolf
,
G. Silva
,
G. Jarvinen
,
A. Cheetham
, and
Kenneth Czerwinski

Abstract  

The chemistry of technetium is being explored at the University of Nevada Las Vegas. Our goal is to investigate both the applied and fundamental aspects of technetium chemistry, with a special emphasis on synthesis, separations, and materials science. The synthetic chemistry focuses on metal–metal multiple bonding, oxides and halides. Synthesis and characterizations of (n-Bu4N)2Tc2X8, Tc2(O2CCH3)4X2 (X = Cl, Br), TcO2, Bi2Tc2O7, Bi3TcO8, TcBr3 and TcBr4 have been performed. The applied chemistry is related to the behavior of Tc in the UREX process. Separation of U/Tc has been conducted using anion exchange resin and metallic Tc waste form synthesized and characterized.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Perera
,
C. Perez
,
M. Torres
,
A. Henandez
,
F. Heres
,
T. Moreira
,
A. Gutierrez
,
A. Gigato
,
I. Hernandez
,
L. Alberti
,
O. Marrero
,
L. Martinez
,
J. Sanfiz
,
E. Sanchez
,
J. Rodriguez
,
L. Marrero
, and
G. Parra

Abstract  

The aim of this work was to obtain a freeze-dried kit for direct99mTc-labeling of human polyclonal IgG. The labeling procedure was carried out by Schwarz's method. The best yields of99mTc-IgG were obtained by using sodium pyrophosphate decahydrate as a weak chelating agent. Performed tests showed the stability of the radiopharmaceutical up to 24 hours. Plasma clearance in rats was fitted to a biexponential curve withT 1/2α=(0.1 ±0.9) h andT 1/2β=(10±3) h. The organs with higher uptake of radiopharmaceutical were lung, kidneys and blood. In a rabbit model the abscess target/background ratio was 3–6 according to time of the scintigraphic images. Thirty patients with musculoskeletal infection were studied. Twenty-one lesions were detected and confirmed by culture/biopsy.

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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:
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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