Experimental device for obtaining calibration factor for the total count technique

Nuclear technologies have widely used on industry plants in order to help to solve troubles processes/design or just obtain information of them. The Total Count technique for flow measurement has as main advantages: being an absolute technique, because it is independent of additional devices readings unless the directly used for recording the radioactive cloud, requiring only a single detector to provide the final result; the independence of the internal volume of the transport duct, can be applied in the presence or absence of obstructions; no restriction as to the nature of the product or material to be conveyed; it is a noninvasive technique which allows real-time diagnostics. To use Total Count Technique, knowledge of a geometric calibration factor is required. Called Factor F, it is obtained in the laboratory using an experimental apparatus to faithfully reproduce the geometry of the detection system and the pipeline that being analyzed and using the same radiotracer, therefore, its value is constant for each specific measuring system under survey. This experimental apparatus for obtaining the factor F consisting by a pipe of 2 "PVC, which simulates a transmission line, where they were deposited 500 ml oil and the use of a specific pipette for use viscous fluids were added sequentially aliquots (50.00 ± 0.01) μl radiotracer (radionuclide photopeak energy of 198 Au 411.8 keV) and analyzing data obtained by three distinct detection systems composed of detectors NaI scintillators 1" x 1" and a data acquisition system

Measurements of indoor 222Rn concentration in two art galleries

It is point out that radon and their decay products in environment give high dose to human lung. Studies indicate that the indoor radon inhalation by humans has been considered probably the second most important cause of lung cancer after of smoking. A passive-type radon detector was used for measuring indoor radon concentration in two art galleries at Rio de Janeiro city during 90 days January to March, 2009. The aim of this study is to evaluate the occupational and public radon exposure in art galleries and museums. This paper shows the preliminary results of samples collected at two art galleries located in Gávea, Rio de Janeiro city. 30 LEXAN (GE) track detectors were exposed in the air (indoor as well as outdoor). The samples were collected in the same building which is a construction of XIX century. The analysis of the results suggests that the 222Rn concentration levels are different in both sampling site, in closed environmental, demonstrating that, although the construction materials are the same the absence of circulating air is a factor very important to increase the concentration of indoor Rn

Evaluation of multielements in human blood samples using synchrotron radiation

Total-reflection X-ray fluorescence using synchrotron radiation (SR-TXRF) is a powerful analytical technique to study trace elements in biomedical samples. The aim of this study was to investigate possible changes in essential trace element concentrations caused by irradiation procedures. Fresh blood samples were obtained from the Dr. Eliel Figueiredo Laboratory, Rio de Janeiro. The samples were separated in two groups. The first was irradiated with doses of 1500, 2500 and 3000cGy, using a Gammacell 220 Exce irradiator, and the second was irradiated with doses of from 2 to 100 cGy, using gamma radiation in a Theraton 780 C irradiator. After irradiation, all samples were lyophilized to remove the water and then submitted to standard chemical digestion by adding nitric acid. All the measurements were carried out by X-Ray Fluorescence beamline at the Brazilian Synchrotron Light Laboratory (LNLS) in Campinas. While no positive association was found for variations in calcium, the variations in potassium were positively associated with the radiation dose for all analyzed samples. On the other hand, iron levels decreased for whole blood and plasma and zinc levels decreased only in whole blood as the dose increased.A técnica de fluorescência de raios X por reflexão total usando radiação síncrotron (SR-TXRF) é uma poderosa ferramenta utilizada para a determinação das concentrações elementares presentes em amostras biológicas. O objetivo deste estudo é avaliar as possíveis alterações causadas por processos de irradiação na concentração de elementos-traço em amostras de sangue humano. As amostras de sangue foram coletadas no Laboratório de Análises Clínicas Dr. Elilel Figueiredo, Rio de Janeiro, e divididas em dois grupos. O primeiro grupo foi irradiado com doses de 1.500, 2.500 e 3.000 cGy, utilizando o irradiador Gammacell 220 Excel, e o segundo foi irradiado com doses que variaram de 2 cGy a 100 cGy, utilizando uma bomba de cobalto Theratron 780 C do Inca, Rio de Janeiro. Todas as amostras de sangue total, plasma e matriz celular foram então liofilizadas e, em seguida, passaram pelo procedimento padrão de digestão. Todas as medidas foram realizadas na linha de fluorescência de raios X do Laboratório Nacional de Luz Síncrotron (LNLS), em Campinas, Brasil. Não se verificou variação significativa na concentração de Ca e, em contrapartida, o K foi o único elemento que sofreu alterações significativas para todas as amostras analisadas em função da dose. A concentração de Fe diminuiu apenas para as amostras de sangue total e plasma. A concentração de Zn apresentou uma diminuição significativa somente para as amostras de sangue total.195202Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code

Purpose: Melanoma at the choroid region is the most common primary cancer that affects the eye in adult patients. Concave ophthalmic applicators with 106Ru/106Rh beta sources are the more used for treatment of these eye lesions, mainly lesions with small and medium dimensions. The available treatment planning system for 106Ru applicators is based on dose distributions on a homogeneous water sphere eye model, resulting in a lack of data in the literature of dose distributions in the eye radiosensitive structures, information that may be crucial to improve the treatment planning process, aiming the maintenance of visual acuity. Methods: The Monte Carlo code MCNPX was used to calculate the dose distribution in a complete mathematical model of the human eye containing a choroid melanoma; considering the eye actual dimensions and its various component structures, due to an ophthalmic brachytherapy treatment, using 106Ru/106Rh beta-ray sources. Two possibilities were analyzed; a simple water eye and a heterogeneous eye considering all its structures. Two concave applicators, CCA and CCB manufactured by BEBIG and a complete mathematical model of the human eye were modeled using the MCNPX code. Results and Conclusion: For both eye models, namely water model and heterogeneous model, mean dose values simulated for the same eye regions are, in general, very similar, excepting for regions very distant from the applicator, where mean dose values are very low, uncertainties are higher and relative differences may reach 20.4%. For the tumor base and the eye structures closest to the applicator, such as sclera, choroid and retina, the maximum difference observed was 4%, presenting the heterogeneous model higher mean dose values. For the other eye regions, the higher doses were obtained when the homogeneous water eye model is taken into consideration. Mean dose distributions determined for the homogeneous water eye model are similar to those obtained for the heterogeneous eye model, indicating that the homogeneous water eye model is a reasonable one. The determined isodose curves give a good visualization of dose distributions inside the eye structures, pointing out their most exposed volume....................................................Cite this article as:Barbosa NA, da Rosa LAR, de Menezes AF, Reis JP, Facure A, Braz D. Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code. Int J Cancer Ther Oncol 2014; 2(3):02038. DOI: 10.14319/ijcto.0203.

Validation of transient time method to calibrate oil flow meters in closed conduits using 123I as the radiotracer

To assure the credibility of commodity transfer operations in the oil and gas industry, calibrated flow meters are used to quantify the movement of fluids in the pipelines. The purpose of this paper is to validate the transient time method (TTM) to calibrate oil flow meters installed in restricted areas, using the 123I-labelled oil as a radiotracer. Traditionally, as proposed by the standard ISO 2975-7:1977 [1] for experiments in an aqueous medium, the TTM is employed by positioning two detectors at separate locations. However, in industrial plants, it is not always possible to install detectors at the distances recommended by the ISO 2975-7. The method proposed in this paper uses four scintillator detectors separated one from each other by 0.30 m and three injections containing 5.0 ml of 123I-labelled oil. The experiments were carried out in an oil flow rig with a turbulent flow profile. The results have reached an uncertainty which is lower than 1.0%

Avaliação de multielementos em amostras de sangue humano usando SR-TXRF Evaluation of multielements in human blood samples using synchrotron radiation

A técnica de fluorescência de raios X por reflexão total usando radiação síncrotron (SR-TXRF) é uma poderosa ferramenta utilizada para a determinação das concentrações elementares presentes em amostras biológicas. O objetivo deste estudo é avaliar as possíveis alterações causadas por processos de irradiação na concentração de elementos-traço em amostras de sangue humano. As amostras de sangue foram coletadas no Laboratório de Análises Clínicas Dr. Elilel Figueiredo, Rio de Janeiro, e divididas em dois grupos. O primeiro grupo foi irradiado com doses de 1.500, 2.500 e 3.000 cGy, utilizando o irradiador Gammacell 220 Excel, e o segundo foi irradiado com doses que variaram de 2 cGy a 100 cGy, utilizando uma bomba de cobalto Theratron 780 C do Inca, Rio de Janeiro. Todas as amostras de sangue total, plasma e matriz celular foram então liofilizadas e, em seguida, passaram pelo procedimento padrão de digestão. Todas as medidas foram realizadas na linha de fluorescência de raios X do Laboratório Nacional de Luz Síncrotron (LNLS), em Campinas, Brasil. Não se verificou variação significativa na concentração de Ca e, em contrapartida, o K foi o único elemento que sofreu alterações significativas para todas as amostras analisadas em função da dose. A concentração de Fe diminuiu apenas para as amostras de sangue total e plasma. A concentração de Zn apresentou uma diminuição significativa somente para as amostras de sangue total.<br>Total-reflection X-ray fluorescence using synchrotron radiation (SR-TXRF) is a powerful analytical technique to study trace elements in biomedical samples. The aim of this study was to investigate possible changes in essential trace element concentrations caused by irradiation procedures. Fresh blood samples were obtained from the Dr. Eliel Figueiredo Laboratory, Rio de Janeiro. The samples were separated in two groups. The first was irradiated with doses of 1500, 2500 and 3000cGy, using a Gammacell 220 Exce irradiator, and the second was irradiated with doses of from 2 to 100 cGy, using gamma radiation in a Theraton 780 C irradiator. After irradiation, all samples were lyophilized to remove the water and then submitted to standard chemical digestion by adding nitric acid. All the measurements were carried out by X-Ray Fluorescence beamline at the Brazilian Synchrotron Light Laboratory (LNLS) in Campinas. While no positive association was found for variations in calcium, the variations in potassium were positively associated with the radiation dose for all analyzed samples. On the other hand, iron levels decreased for whole blood and plasma and zinc levels decreased only in whole blood as the dose increased

Assesment of array scintillation detector for follicle thyrioid 2D-image acquisition using Monte Carlo Simulation

This work presents an innovative study to find out the adequate scintillation inorganic detector array to be used coupled to a specific light photo sensor, a charge coupled device (CCD), through a fiber optic plate. The goal is to choose the type of detector that fits a 2-dimensional imaging acquisition of a cell thyroid tissue application with high resolution and detection efficiency in order to map a follicle image using gamma radiation emission. A point or volumetric source –detector simulation by using a MCNP4B general code, considering different source energies, detector materials and geometry including pixel sizes and reflector types was performed. In this study, simulations were performed for 7x7 and 127x127 arrays using CsI (TU) and BGO scintillation crystals with pixel size ranging from 1x1 cm2 to 10 x 10 µm2 and radiation thickness ranging from 1 mm to 10 mm. the effect of all these parameters was investigated to find the best source-detector system that result in an image with the best contrast details. The results, showed that it is possible to design a specific imaging system that allows searching for in-vitro studies, specifically in radiobiology applied to endocrine physiology

Estudo de perfil de espalhamento usando difração de raios X de amostras de sangue irradiadas Study of X-ray diffraction scattering profiles in irradiated blood samples

O aumento nas aplicações das radiações ionizantes pode produzir exposição de pessoas e objetos a campos de radiação, onde a intensidade depende do tipo da fonte e da atividade desenvolvida. Nesse trabalho, perfis de espalhamento de amostras liofilizadas de plasma, matriz celular e sangue total foram estudados. Os perfis de espalhamento foram obtidos com um difratômetro de raios X Shiamadzu (XRD6000) no Laboratório de Instrumentação Nuclear, LIN/Coppe. As amostras foram irradiadas com valores de dose de 2cGy a 100cGy no Inca, no Rio de Janeiro, e todas as amostras de plasma, matriz celular e sangue total foram liofilizadas a -60°C e 780 mmHg até completa eliminação de água. Os ângulos de espalhamento de 5° a 35° foram varridos em passos de 0,05° com tempo de integração de 3 segundos. Os perfis de espalhamento das amostras irradiadas foram comparados com os perfis de amostras não irradiada. Nesse estudo observou-se que os perfis das amostras de matriz celular e sangue total são bastante parecidos. O perfil de espalhamento do plasma é muito característico porque em adição ao primeiro e ao segundo pico essas amostras mostraram mais dois picos estreitos.Os valores de &#952;1 e &#952;2 das amostras de plasma irradiado são maiores que os obtidos pelas amostras de plasma não irradiado e os valores de &#952;1 e &#952;2 das amostras de matriz celular irradiada são menores que os obtidos pelas amostras de matriz celular não irradiada.The increase in ionizing radiation (IR) applications can expose people and objects to radiation fields, where the intensity depends on the type of source and the activity. In this work, scattering profiles of lyophilized samples of plasma, cellular matrix and total blood were studied. The scattering profiles were obtained using a Shiamadzu X-Ray diffractometer (XRD 6000) at the Laboratório de Instrumentação Nuclear, LIN/Coppe. The samples were irradiated with doses of from 2cGy to 100cGy at Inca in Rio de Janeiro and all the samples of plasma, cellular matrix and total blood were lyophilized at -60°C and 780 mmHg until the water was totally eliminated. Scanning involved scattering angles of from 5° to 35° in steps of 0.05° with an integration time of 3 seconds. The scattering profiles of the irradiated samples were compared with non-irradiated sample profiles. In this study it was observed that the cellular matrix and total blood sample profiles are similar. The scattering profile of plasma is very characteristic because in addition to the first and second peaks, these samples show two other narrow peaks. The 1 and 2 values of irradiated plasma samples are greater than non-irradiated ones and the 1 and 2 values of the irradiated cellular matrix samples are smaller than ones obtained using non-irradiated cellular matrix samples

Avaliação de multielementos em amostras de sangue humano usando SR-TXRF

A técnica de fluorescência de raios X por reflexão total usando radiação síncrotron (SR-TXRF) é uma poderosa ferramenta utilizada para a determinação das concentrações elementares presentes em amostras biológicas. O objetivo deste estudo é avaliar as possíveis alterações causadas por processos de irradiação na concentração de elementos-traço em amostras de sangue humano. As amostras de sangue foram coletadas no Laboratório de Análises Clínicas Dr. Elilel Figueiredo, Rio de Janeiro, e divididas em dois grupos. O primeiro grupo foi irradiado com doses de 1.500, 2.500 e 3.000 cGy, utilizando o irradiador Gammacell 220 Excel, e o segundo foi irradiado com doses que variaram de 2 cGy a 100 cGy, utilizando uma bomba de cobalto Theratron 780 C do Inca, Rio de Janeiro. Todas as amostras de sangue total, plasma e matriz celular foram então liofilizadas e, em seguida, passaram pelo procedimento padrão de digestão. Todas as medidas foram realizadas na linha de fluorescência de raios X do Laboratório Nacional de Luz Síncrotron (LNLS), em Campinas, Brasil. Não se verificou variação significativa na concentração de Ca e, em contrapartida, o K foi o único elemento que sofreu alterações significativas para todas as amostras analisadas em função da dose. A concentração de Fe diminuiu apenas para as amostras de sangue total e plasma. A concentração de Zn apresentou uma diminuição significativa somente para as amostras de sangue total