Research Article
Evaluation of Environmental Radioactivity and Estimation of Radiation Exposure in the Niankhene Agricultural Field in Senegal
Djicknack Dione*,
Papa Macoumba Faye,
Moussa Hamady Sy,
Oumar Ndiaye,
Nogaye Ndiaye,
Alassane Traoré,
Ababacar Sadikhe Ndao
Issue:
Volume 9, Issue 1, March 2024
Pages:
1-7
Received:
22 February 2024
Accepted:
4 March 2024
Published:
19 March 2024
DOI:
10.11648/j.ns.20240901.11
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Abstract: The presence of radioactivity, originating from both natural and human-induced sources, is widespread in varying degrees throughout the Earth's crust. Soil, as a fundamental component of the Earth's crust, serves as an ongoing source of exposure to humans. The level of radioactivity in soil is influenced by factors such as soil composition and land usage. It is expected that barren soil exhibits distinct radioactivity levels compared to cultivated soil. To investigate the radioactivity levels within barren soil, a study was conducted on approximately 11 hectares of soil samples located in Niankhene. Utilizing gamma ray spectrometry methodology with a high purity germanium gamma-ray detector, activity concentration levels of radionuclides including 40K, 137Cs, 226Ra, and 232Th were evaluated. A total of 16 soil samples were collected at depths ranging from 0 to 40 cm with 20 cm intervals. The activity concentrations of the radionuclides were observed as follows: 40K ranged from below the limit of detection to 34.7 Bq.kg-1; 137Cs varied from 0.06 to 0.80 Bq.kg-1; 226Ra measured was between 7.49 and 101.56 kg-1; and 232Th ranged 0.33 and 12.68 Bq.kg-1. The total dose radiation exposure were 27 nGy/h in this study. Before conducting radiometric measurements, chemical analyses were performed to determine the concentrations of Na, Ca, and Mg, along with measurements of electrical conductivity and pH levels of the soil samples.
Abstract: The presence of radioactivity, originating from both natural and human-induced sources, is widespread in varying degrees throughout the Earth's crust. Soil, as a fundamental component of the Earth's crust, serves as an ongoing source of exposure to humans. The level of radioactivity in soil is influenced by factors such as soil composition and land...
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Review Article
Overview on Spectral Analysis Techniques for Gamma Ray Spectrometry
Masayuki Imaizumi*
Issue:
Volume 9, Issue 1, March 2024
Pages:
8-29
Received:
26 March 2024
Accepted:
17 April 2024
Published:
10 May 2024
Abstract: Gamma-ray spectrometry (GRS) is an exploration technology that distinguishes itself from other non-contact sensing technologies because it provides information from 30 to 50 cm below the ground. This technology has evolved through three significant turning points in mapping output. The first turning point, in the 1960s-1970s, was the transition from U concentration maps to weathered zoning maps utilizing K or eTh. The second turning point, occurring from the 1980s to 1990s, was marked by the application of radionuclide mapping to assess radioactive contamination. A third turning point, in the early 2000s, was the development of soil maps for precision agriculture, supported by the free statistics software R. This paper reviews advances in gamma-ray spectrometry spectral analysis since 2000. Traditionally, the gamma-ray spectrum is depicted as a two-dimensional graph with energy on the horizontal axis and counts on the vertical axis. The NASVD and MNF methods, developed around 2000, necessitate a reevaluation of this concept. By conducting principal component analysis of the gamma-ray spectrum in hyperspace, these techniques have unveiled new spectra, such as ground and sky spectra, and have facilitated the removal of noise components from the gamma-ray spectrum. Naturally occurring gamma-ray spectra typically exhibit energies ranging from 0.04 to 3 MeV. Observations from fusion reactors measure energies up to 20 MeV for diagnostics of nuclear plasma. These spectra may yield valuable insights when applied to innovative statistical analysis techniques. A comprehensive spectral analysis method developed in the early 2000s has demonstrated the potential to extract a variety of information beyond window nuclides, previously unexplored. The regression coefficient plots from the PLSR regression model have revealed novel spectral images. This model is set to influence future research on GRS by expanding the number of objectives and covariates. The innovative calibration method for full-spectrum analysis, which assesses different concentration areas, has proven that calibration is achievable even in the absence of a calibration pad. It is expected to become a formidable approach for spectrum analysis in the upcoming period.
Abstract: Gamma-ray spectrometry (GRS) is an exploration technology that distinguishes itself from other non-contact sensing technologies because it provides information from 30 to 50 cm below the ground. This technology has evolved through three significant turning points in mapping output. The first turning point, in the 1960s-1970s, was the transition fro...
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