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Abstract  

On 13 September 1987, a severe radiation accident occurred in the city of Goiânia in central Brazil. Approximately 250 people were directly affected by the radiation, receiving slight to very severe external, partial or whole body, irradiation, and presenting internal and external contamination. Fourteen patients developed some degree of marrow failure, eight developed the clinical signs and symptoms of acute radiation syndrome (ARS), and four eventually died of ARS complications. Twenty-eight people showed acute localized radiation injuries ranging from first to third degree. The author describes the circumstances of the event, the first-aid measures taken on the site, and the medical structure organized to triage and treat the casualties. Aspects relating to hospital contamination control, radiation protection and decontamination procedures are also discussed.

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Abstract  

The zirconium isotope 93Zr is a long-lived pure β-particle-emitting radionuclide produced from 235U fission and from neutron activation of the stable isotope 92Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half life, 93Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Measurement of 93Zr is difficult owing to its trace level concentration and its low activity in nuclear wastes and further because its certified standards are not frequently available. A radiochemical procedure based on liquid–liquid extraction with 1-(2-thenoyl)-3,3,3-trifluoroacetone in xylene, ion exchange with Dowex resin and selective extraction using TRU resin has to be carried out in order to separate zirconium from the matrix and to analyze it by liquid scintillation spectrometry technique (LSC). To set up the radiochemical separation procedure for 93Zr, a tracer solution of 95Zr was used in order to follow the behavior of zirconium during the process by γ-ray spectrometry through measurement of the 95Zr. Then, the protocol was applied to low level waste (LLW) and intermediate level waste (ILW) from nuclear power plants. The efficiency detection for 63Ni was used to determination of 93Zr activity in the matrices analyzed. The limit of detection of the 0.05 Bq l−1 was obtained for 63Ni standard solutions by using a sample:cocktail ratio of 3:17 mL for OptiPhase HiSafe 3 cocktail.

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Abstract  

A procedure for the simultaneous determination of241Am and239Pu or238Pu was carried out in samples such as air filters, sweep-tests, aqueous solutions and urine. The method described here includes a previous treatment of the samples in accordance with the type of matrix in which the actinides are included and a liquid scintillation counting using a two-phase cocktail. The upper detection limit was estimated to be 50 mBq for a 50-minute counting time.

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Summary  

Targeted radiotherapy has the potential to provide radiation doses from a wide range of radionuclides, some of them suitable for killing single cells while others are more suitable for killing tumor cell clusters of various sizes. A list of 64 radionuclides, including 20 new potential candidates for therapy (73Ga, 75Se, 87mSr, 97Ru, 103Ru, 113Sn, 113mIn, 117Sb, 123Sn, 131Cs, 139Ce, 141Ce, 149Eu, 167Tm, 170Tm, 173Tm, 195Au, 195mPt, 197Pt and 197Hg) were analyzed in terms of the suitability of their energies for killing tumor cells which grow as single, small, intermediate and large clusters. In addition, their possible production routes were studied.

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Abstract  

A passive diffusion method for the determination of radon concentration has been optimised and calibrated. The device consists of a scintillation vial containing activated charcoal, a diffusion barrier and a desiccant agent. The response to diverse atmospheric humidity and variable exposure intervals was studied. The result is a detector independent of atmospheric humidity till 7 days of exposure. The method was compared with electret detectors (US EPA) with very satisfactory results. The advantages of this method are its simplicity, low cost, low detection limit, the total automatization of the measurement and its total independence of humidity to measure in a wide range of radon concentrations.

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Summary This paper studies annihilating properties of operators generated by spherical convolution over the unit sphere O2q of Cq. Its specific aim is to answer the following question: given a complex number ?, |?|=1, to determine what functions of L 2(O2q) have zero average over every section  Ow ?,q  :={ z ?O2q: <z,w> = ?} of O2q . Here, <.,.>stands for the usual inner product of Cq.

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Abstract  

Data are presented for210Po levels in edible parts of marine species significant in the diet of the Argentine population. The sample collection sites were situated between 35° and 45° S in the Atlantic Ocean. The specific activities obtained, expressed per wet veight and with a 95% confidence level, ranged between 31.3±9.1 mBq kg–1 for pollack (Genypterus blacodes) and 1790±280 mBq kg–1 for squid (Illex argentinus). Hake (Merluccius hubbsi) followed by squid are the major contributors to the dose. The annual committed effective doses were 0.7 mSv and 0.6 mSv and the effective collective doses were 24 man·Sv and 20 man·Sv, respectively, for these species. For the remainder, because of both their low consumption rates and low specific activities, the corresponding doses were negligible compared with the former.

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Abstract  

The effect of the iron precursor on the thermal decomposition of iron oxyhydroxides was studied by DSC, DTA and TG in this work. Samples were prepared from iron nitrate, iron sulfate and iron chloride and the thermal curves obtained were analyzed by specific area measurements, X-ray diffraction and Mssbauer spectroscopy. It was found that the iron oxyhydroxide precursors affect the temperatures of the hematite formation as well as the textural properties of the final hematite producing particles with different diameters as following: iron sulfate (3.3 nm)<iron nitrate (15 nm)<iron chloride (24 nm).

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Cibele Zamboni, Sabrina Metairon, Laura Oliveira, Simone Simons, A. Chudzinski-Tavassi, and Daniella Oliveira

Abstract  

The determination of elemental concentrations for Br, Ca, Cl, Fe, K, Mg, Na, S, Sr, and Zn in blood samples from White New Zealand rabbits was performed applying the NAA technique. Twenty whole blood samples (12 male and 8 female) collected in research centers from Brazil (Aggeu Magalhães in Recife and Butantan Institute in São Paulo) were investigated, using the IEA-R1 nuclear reactor at IPEN/CNEN-SP-Brazil. These data can be used as references to perform biochemistry analyses in veterinary medicine using small quantities of whole blood (100–400 μL), simplifying the collection and the preparation of biological samples (it is not necessary to perform the serum separation nor to use specific reactants). Furthermore, the knowledge of the biochemical values in blood allows us to check the similarities with the blood estimations in human beings, which is an important condition for selecting laboratory animals. Finally, these data suggest a great similarity of the inorganic tissue profile of rabbits (White New Zealand) and humans.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Iwahara, L. Tauhata, A. Oliveira, I. Nícoli, F. Alabarse, A. Xavier, M. Oliveira, M. Koskinas, and M. Almeida

Abstract  

Proficiency tests established by ISO/IEC-43 were applied to assess the performance of 69 Brazilian nuclear medicine services in the radiopharmaceuticals activity measurements of 131I, 99Tcm, 67Ga and 201Tl. The 214 datasets originated from comparison programs promoted by the Laboratório Nacional de Metrologia das Radiações Ionizantes (LNMRI) in 2006/2007 were also evaluated against acceptance criteria of ±10% limits for accuracy required by Brazilian regulatory authority. The results of performance evaluation were assigned as “Acceptable” or “Not-acceptable” accordingly and have shown a large dispersion when the statistical criteria assays were applied and also compared with regulatory requirements.

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