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Analysis of gas-chromatographic method for the determination of ethanol in an 18-F-fluorodeoxyglucose (FDG-18) solution: shor communication.
No full textA gas chromatographic method for determination of ethanol in an fluorodeoxyglucose (FDG)-18
solution was developed. The pre-validation tests were made to test some parameters. Three samples in
the concentration of 400, 4000 and 7200 ppm, respectively were analyzed using the novel methodology.
The results of the technique were not good. Although the method seems to be capable to identify
ethanol in solution, the pre-validation demonstrated a problem in the technique. The linearity results
showed an R2 of 0.66. Further tests must be made to implement this technique in a daily routine
Application of the Finite Element Method in Steady-State Diffusion Equation
Get PDFHere, the steady-state neutron diffusion equation is solved to obtain the effective multiplication factor and the neutron flux distribution of a nuclear core reactor. Two different implementations are applied to this problem. In one implementation a classic formalism of finite difference method is used whereas in the other one, a more modern formalism of finite element method which mesh is automatically generated using an error indicator based in the continuity of the neutron current. The method is evaluated in two geometric core configurations: the one-dimensional and the two-dimensional case. In the second case the core homogenization is performed in two ways: in a fuel element level (macro cell) and in a rod element level (micro cell) using two groups of energy. The finite element results are compared with the ones generated by the finite difference method, taken as a reference. The case of one-dimensional slab core reactor, described for the BSS-6-A1 numerical benchmark, and the Ulchin1 two-dimensional core reactor had been tested. A good agreement between the methods can be verified
Construção de nova interface de operação para o simulador do LABIHS utilizandon o software Eclipse E3 Studio
No full textO Laboratório de Interfaces Homem-Sistema (LABIHS) é composto por um conjunto de equipamentos e programas de computador que simulam os processos de uma usina nuclear (NPP) de reator de água pressurizada (PWR) de 930 MWe de potência, formando um simulador compacto operado através de painéis de controle em software que representam os vários sistemas de uma usina nuclear, rodando em um conjunto de computadores de trabalho que representam uma sala de controle avançada. Uma das linhas de pesquisa do LABIHS é o desenvolvimento de novas interfaces homem-sistema. Este relatório apresenta o processo de desenvolvimento de cada componente de tela de uma nova interface homem-sistema para o simulador, similar à interface anterior, utilizando o software Elipse E3 Studio. Ao final do relatório são apresentadas as novas telas, construídas com os novos componentes, todos criados no software Elipse E3 Studio
Radionuclide identification using subtractive clustering method
Get PDFRadionuclide identification is crucial to planning protective measures in emergency situations. This paper presents the application of a method for a classification system of radioactive elements with a fast and efficient response. To achieve this goal is proposed the application of subtractive clustering algorithm. The proposed application can be implemented in reconfigurable hardware, a flexible medium to implement digital hardware circuits
On the precision and accuracy of the acoustic birefringence technique for stress evaluation
Get PDFThis paper presents a numerical procedure for estimation of the precision and accuracy of the acoustic birefringence technique as used in the Instituto de Engenharia Nuclear (IEN) for evaluation of residual and applied stresses in structures and components, mainly of the nuclear power industry. This procedure shall be incorporated to the signal processing module of the ultrasonic system used at IEN’s Ultrasonic Laboratory to account in an automatic and systematic way for the uncertainties in the input data and their propagation throughout the calculations. The acoustic birefringence is generally defined from the speeds of two mutually
orthogonal volumetric waves of normal incidence, but when the use of a pulse-echo measurement system is feasible, the birefringence can be defined directly from the time-of-flight of the waves, since they travel the same physical space. The times-of-flight of the waves can thus be regarded as the primary variables of interest. They are estimated by coupling the mathematical techniques of cross correlation and data interpolation, whereas the material’s acoustoelastic constant is determined via a weighted linear regression. An Excel spreadsheet performs all calculations taking into account the uncertainties and the number of significant digits in the results. As an example of the procedure developed, the estimation of the precision and accuracy in the evaluation of the stresses acting in a beam under bending is presented. The analytical solution derived from the strength of materials theory was used as the reference value for accuracy estimation purpos
Calculation of financial compensation due of municipalities hosting nuclear waste deposit
Get PDFThe present work evaluates the math from monthly financial transfers to municipalities with technical viability
for building of initial or intermediate repository for storing of radioactivity nuclear waste: gloves, sneakers,
mask, resins and filters came from thermonuclear facilities. Several aspects have been considered as the
geological factors of the site as presence of capable faults, groundwater vulnerability, infiltration of seawater.
Also, it was take into account socioeconomic factors: population density, costs for construction, maintenance
and operation of repository; size and activity of waste; among others. Hereafter, we have presented the key features of low and average activity repository and high activity repository even as initial, intermediate and final repository and the possible environment impact. The methodology for calculation of financial compensation of municipalities was established by CNEN will be applied for a specific assumed municipality. The analysis of financial compensation due to the specific nuclear waste deposit and the possible guidelines for the use of that compensation by the municipality will be analyzed. In addiction, it will be compared the model for compensation used for nuclear wastes with other plants receiving permanent wastes from cemeteries and sanitary landfills, where the land should not be allowed for the human activities the same as: crops, livestock and buildings. Also, comparison with royalties and indemnities were paid by facilities of energy production as hydroelectric dams as well as petroleum and gas exploration plants. The destination of financial compensation transfer to the municipality is in charge of the city administration. The compensation could be applied of investments in education and culture, health, sanitation works, improvement of public transport, environment, among others. It will be discussed the cost-benefit relation for the assumed municipality
Analysis of information exchange activities to actualize and validate situation awareness during shift changeovers in nuclear power plants.
No full textTemperature Distribution on Fuel Rods: A Study on the Effect of Eccentricity in the Position of UO2 Pellets
No full textEste trabalho trata de um estudo de condução de calor em elementos de combustível do tipo haste. Um método de
resolver as equações de transferência de calor aplicados em barras de combustível nuclear, utilizando o método de elementos finitos
foi desenvolvido a fim de avaliar o desempenho de sistemas de segurança e nucleares. A
código computacional foi desenvolvido a fim de avaliar as equações que governam o problema,
a fronteira, e as condições iniciais. Este programa é acoplado a GiD, que é um universal,
pré e pós-processador para simulações numéricas em ciência adaptativa e user-friendly e
engenharia. O método foi validado contra uma solução analítica derivada por Nijsing em
referência [1] com o erro menos do que 1,4% e com respeito a uma solução analítica melhorada
apresentados na referência [2] para a haste axisymmetric e rod excentricidade com erro de menos de um 3,6%.
Os pedidos foram desenvolvidos utilizando temperatura propriedades físicas dependentes para o
resolução de uma haste de simetria axial e para a resolução de uma haste com excentricidade. o presente
método permite a análise de barras de combustível, nas situações previstas e outros cenários, também, é uma
ferramenta substancial para a análise de barras de combustível.This work deals with a study of heat conduction in rod type fuel elements. A method of
solving the heat transfer equations applied in nuclear fuel rods using the finite element method
was developed in order to evaluate the performance and safety of nuclear systems. A
computational code was developed in order to evaluate the equations governing the problem,
the boundary, and initial conditions. This program is coupled to GiD, which is a universal,
adaptive and user-friendly pre and postprocessor for numerical simulations in science and
engineering. The method was validated against an analytical solution derived by Nijsing in
reference [1] with error less than 1.4% and with respect to an improved analytical solution
given in reference [2] for axisymmetric rod and eccentricity rod with error less than a 3.6%.
Applications have been developed using temperature dependent physical properties for the
resolution of an axisymmetric rod and for the resolution of a rod with eccentricity. The present
method allows the analysis of fuel rods in the given situations and other scenarios, also, it is a
substantial tool for the analysis of fuel rods
RADIOPHARMACEUTICALS PACKAGE MONITORING SYSTEM
No full textOs radiofármacos são usados no campo da medicina nuclear como marcadores no diagnóstico e no tratamentode muitas doenças. A produção de um radiofármaco envolve dois processos principais: a produção
do radionuclídeo em que farmacêutica baseia-se, e a preparação e embalagem de
o radiofármaco completa. Antes de enviar radiofármacos de pacotes para os usuários, cada
pacote deve ser rotulado de acordo com o nível máximo de radiação medida na sua superfície, de acordo com
as diretrizes de proteção radiológica CNEN-NE-5.01, para garantir que os contentores de transporte em conformidade com regulamentação
requisitos para o transporte de radiofármacos. Este trabalho descreve o monitoramento pacote
sistema desenvolvido para a ajuda ao pessoal de radioproteção no processo de radiofármacos pacote monitor.
O sistema foi instalado e testado no local de expedição radiofármacos pacote quarto do IEN
e mostrou boa contribuição para reduzir a dose de radiação para o pessoal de radioproteção durante o
processo medida pacote.Radiopharmaceuticals are used in the field of nuclear medicine as tracers in the diagnosis and treatment
of many diseases. The production of a radiopharmaceutical involves two main processes: the production
of the radionuclide on which the pharmaceutical is based, and the preparation and packaging of
the complete radiopharmaceutical. Before dispatching package radiopharmaceuticals to the users, each
package must be labeling according to the maximum radiation level measured at its surface, according to
the radiation protection guidelines CNEN-NE-5.01, to ensure that transport containers comply with regulatory
requirements for transport of radiopharmaceuticals. This work describes the package monitoring
system developed for help to radioprotection personnel in the process of monitor package radiopharmaceuticals.
The system was installed and tested at IEN’s dispatch package radiopharmaceuticals room
and showed good contribution to reduce the radiation dose to the radioprotection personnel during the
package measure process
Site selection process for new nuclear power plants-a method to support decision making and improving public participation
Get PDFThe Brazilian Energy Plan (PNE 2030) that guides the Government in formulating its strategy for expanding energy supply by 2030 highlights the need for the Brazilian electrical system have more than 4,000 MW from nuclear sources by 2025. Therefore, the Government presented a proposal to build four more nuclear power plants with capacity of 1,000 MW each, at first, two in the Northeast and two in Southeast. The selection and site assessment are key parts of the installation process of a nuclear plant and may significantly affect the cost, public acceptance and safety of the facility during its entire life cycle. The result of this initial stage, it can even seriously affect program success. Wrong decisions in the process of site selection may also require a financial commitment to higher planned in a later phase of the project, besides causing extensive and expensive downtime. Select the location where these units will be built is not a trivial process, because involves the consideration of multiple criteria and judgments in addition to obtaining, organizing and managing a diverse range of data, both qualitative and quantitative, to assist in decision making and ensure that the site selected is the most appropriate in relation to safety and technical, economic and environmental feasibility. This paper presents an overview of the site selection process and its stages, the criteria involved in each step, the tools to support decision making that can be used and the difficulties in applying a formal process of decision making. Also discussed are ways to make the process more transparent and democratic, increasing public involvement as a way to improve acceptance and reduce opposition from various sectors of society, trying to minimize the expense and time involved in the implementation of undertakings of this kind