Applied tools for determining low-activity radionuclides in large environmental samples

Abstract

Considerable amounts of biological material contaminated with artificial radionuclides were generated to obtain the efficiency curves for low-activity radionuclide analyses of large environmental samples. Likewise, improving detection geometry is also an important task, mainly for studies involving conservation units with a high level of biodiversity preservation. This study aimed to evaluate the Monte Carlo efficiency curves without generating contaminated material with artificial radionuclides for water and vegetation measurements. An in-house adapted Marinelli geometry was applied to reduce the sampled amount of biological material in the ecosystem, which was combined with the Monte Carlo assisted efficiency curve for a more sustainable radiometric analysis.

226Ra, 228Ra and 40K in scales from boilers of industrial installations

“…For each radioisotope, the activity concentration was determined by integrating all counts after subtraction of background count under the peak corresponding to the gamma energy emitted by that particular radioisotope, considering that there is no interference of other gammaray lines from other radionuclides [13].…”

“…Gamma spectrometry is today one of the most widely used methods to measure the activity of radionuclides in complex matrices, since it eliminates complex chemical methods. This methodology is also able to measure simultaneously several radioisotopes [13].…”

Radioactive Source-Detector System: Design and Monte Carlo Opinion

“…Also, the current simulation provides a deep understanding of the interactions that occur in a real physical practical system. As can be done by experimental 5,6 or theoretical 7,8 approaches, Monte Carlo technique has been used in gamma detection techniques which have a fundamental role in the field of gamma-rays spectroscopy 9,10 applied in nuclear physics, radiation measurement of environmental samples radiation dosimetry [11][12][13][14][15] , medical radiography 16 , neutron activation analysis 17 , well logging 18 , and study of cosmic rays 19 .…”

Optimization for the radiometric analysis of environmental matrices by high resolution gamma spectrometry

“…Este detector teve seu cristal de germânio caracterizado pelo fabricante, o que permitiu a geração da curva de eficiência 52 utilizada na identificação e quantificação de radionuclídeos naturais ou artificiais de diversas matrizes ambientais, por meio de um detector de radiação acoplado a um sistema eletrônico de aquisição de dados. A técnica consiste na análise de um espectro de emissão específico de radiação gama, permitindo a identificação da natureza e a determinação da atividade dos radionuclídeos presentes na amostra, sem a necessidade de tratamento químico (Paiva et al, 2015). A determinação de radionuclídeos quando em baixas concentrações por meio da técnica de EGAR nem sempre é possível, pois diversos parâmetros como massa, geometria, eficiência de detecção e homogeneidade influenciam diretamente os resultados analíticos e aumentam as atividades mínimas detectáveis.…”