RESUMEN
The neutron activation of stable isotopes in environmental matrices, such as soil and groundwater, is a critical aspect of assessing the impact of radionuclide production facilities on the surrounding ecosystem. The envisioned Low-Energy Radioactive Ion Beams (LERIB) facility at the iThemba LABS, South Africa is anticipated to generate significant sources of ionising radiation. The study investigated the possible repercussions of neutron irradiation stemming from the facility, focusing on the activation of stable isotopic compositions in the environment. The investigation employed a combination of experimental and analytical techniques to characterize the neutron activation products in soil and groundwater samples collected from the vicinity. Samples were collected from designated areas for background radiological measurements and were irradiated with neutrons for a period of 1 h. The induced radioactivity measured by the High Purity Germanium detector included 24Na, 22Na, 54Mn, 52Mn, and 46Sc. The application of Darcy's law for groundwater velocity suggests that radionuclides in groundwater will migrate at an average flow velocity of 0.8 m/day. The isotopes with longer half-lives have count rates at background concentrations; therefore, environmental impacts on the site and surrounding communities might be minimal.
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Agua Subterránea , Monitoreo de Radiación , Contaminantes Radiactivos del Agua , Agua Subterránea/química , Agua Subterránea/análisis , Sudáfrica , Contaminantes Radiactivos del Agua/análisis , Monitoreo de Radiación/métodos , Suelo/química , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos/análisis , Análisis de Activación de Neutrones , Neutrones , Isótopos/análisisRESUMEN
Abnormal levels of potassium are linked to several health conditions, including high blood pressure, cardiac dysfunction, kidney damage, and osteoporosis. Given the limited availability of in vivo measurement techniques, there is a need for novel methods to measure potassium to enhance the diagnosis and management of potassium metabolism related diseases. This study aimed to evaluate the feasibility of compact neutron generator based in vivo measurement system for quantification of potassium using rat carcasses. A cohort of thirty-nine rats (n = 20 males and 19 females, average weight 255 ± 15 and 163 ± 7 g) were sacrificed, and their carcasses were placed in polyethylene bottles. The rats were then positioned and irradiated in a carefully designed irradiation cave built alongside the neutron generator with an optimized thermal neutron flux and radiation dose ratio. The irradiation time was 10 min, followed by a 5-min decay and 2-h measurement using a high efficiency high purity germanium detector(HPGe). RESULTS: The average potassium concentration in male and female rats was found to be comparable (male 2874 ± 161 and female 2866 ± 144 µg/g). A marginally positive correlation between potassium concentration and weight was found in female rats only (male(20) = 0.07, P = 0.76 and female r(19) = 0.34, P = 0.15). We assessed the influence of manganese toxicity on potassium levels and observed no significant impact. These results were consistent with our previous study in mice. CONCLUSION: This study suggests that in vivo neutron activation analysis could serve as a promising method to quantify potassium and to investigate the storage and metabolism of potassium in human and in animals.
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Potasio , Animales , Análisis de Activación de Neutrones/métodos , Femenino , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Our study aimed to assess the soil quality in Punjab's Hoshiarpur district through a meticulous analysis of nutrient and elemental composition. Using a variety of analytical techniques, including Neutron Activation Analysis (NAA), external Particle-induced Gamma-ray Emission (PIGE) an Ion beam analysis Technique, and energy-dispersive X-ray fluorescence (ED-XRF), we delved into soil characterization for 22 agricultural soil samples in the Punjab region. Within the NAA framework, utilizing the Pneumatic Carrier Facility and the self-serve facility at Dhruva reactor in Mumbai, a brief 1-min irradiation procedure identified pivotal elements-Na, Mg, V, Al, Mn, and K. Conversely, an extended neutron irradiation process of approximately 4 h within the self-serve facility enabled the estimation of nearly 12 elements, including Rare Earth Elements (REEs), Transition elements, and other significant elements. The external PIGE technique quantified low Z elements (Na, Mg, Al, and Si), contributing to our analytical arsenal. Rigorously validating both NAA and PIGE methodologies, we compared results meticulously against established geological standard reference materials-specifically USGS RGM-1 and USGS AGV-1.Instrumental in elemental analysis, ED-XRF spectroscopy fortified our investigative endeavors by quick assessment of ten crucial elements. The elemental analysis revealed notable accumulations of Mn and Zn in the soil, surpassing the suggested permissible limits, whereas Co, Cr, and Pb were found to be within the recommended thresholds set by WHO/UNEP. Beyond elemental profiling, our study extended to estimate the accumulation levels of various elements utilizing ecological risk factors such as Contamination Factor, Potential Ecological Risk Index, Pollution Load Index, and Geoaccumulation Factor. Our findings highlighted significant accumulation of REEs including La, Sm and Yb.. This evaluation sheds new light on the interplay between soil composition and environmental health, emphasizing the need for advanced accessible agricultural technologies to prevent and forecast contaminant discharge in arable soil. This commitment aligns with our broader goal of advancing sustainable practices in soil management.
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Agricultura , Monitoreo del Ambiente , Suelo , Suelo/química , India , Monitoreo del Ambiente/métodos , Análisis de Activación de Neutrones , Espectrometría por Rayos X/métodos , Contaminantes del Suelo/análisisRESUMEN
Burullus lagoon is part of Egypt's protected area network. The lagoon serves as a reservoir for drainage water discharged from agricultural areas, and the lake's sediments provide a unique opportunity to record environmental behavior and reconstruct of the heavy metal contamination history. In the present study, the sediment chronology, sedimentation rates, and metal accumulation fluxes were estimated in four sediment cores using 210Pb dating models to evaluate how human activities have affected the coastal environment. Using the radioisotopes 210Pb and 137Cs, radiometric dating was carried out using gamma-ray spectrometry. At the Egypt Second Research Reactor (ETRR-2), the element concentrations were determined using the instrumented neutron activation analysis (INAA- k0 method). Our findings show that the constant rate of supply (CRS), which has been verified with the peak of artificial radionuclide 137Cs, is the best model performed for the chronology of Burullus Lagoon. The average sedimentation rate, according to 210Pb dating models, is 0.85 cm/year. The large variation in sedimentation rates, especially after the 1990s, is consistent with an increase in the anthropogenic flux of heavy metals. This may be led into a significant environmental problem such as reducing the size of the lake and degrading the quality the water in Burullus Lagoon. Enrichment factor (EF) of the studied elements displayed the following order: Cl > Ca > Na > Br > Zn > Ta > Ti > V > Cr > Sc > Mg > Mn > Fe > Hf which is higher than unity. Furthermore, the Nemerow pollution index (PI Nemerow) revealed that pollution was increasing in the direction of the drains and slightly polluted. Consequently, pollutant indices showed that urbanization and industrial development may have increased the depositional fluxes of the metals in sediments over time.
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Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados , Contaminantes Químicos del Agua , Egipto , Metales Pesados/análisis , Sedimentos Geológicos/química , Análisis de Activación de Neutrones , Contaminantes Químicos del Agua/análisisRESUMEN
ABSTRACT: Boron neutron capture therapy (BNCT) is an ideal binary targeted radiotherapy for treating refractory tumors. An accelerator-based BNCT (AB-BNCT) neutron source has attracted more and more attention due to its advantages such as higher neutron yield in the keV energy region, less gamma radiation, and higher safety. In addition to 10 B, neutrons also react with other elements in the treatment room during BNCT to produce many activation products. Due to the long half-life of some activation products, there will be residual radiation after the end of treatment and the shutdown of the accelerator, which has adverse effects on radiation workers. Therefore, the ambient dose equivalent rate in the treatment room needs to be evaluated. The AB-BNCT neutron source model proposed by Li is studied in this paper. Based on the Monte Carlo method, the Geant4 platform was used to simulate the dose induced by radionuclides near the Beam Shaping Assembly (BSA) of the source. It is concluded that the concrete wall contributed the most to the radiation dose. The dose rate of 2.45 µSv h -1 after 13 min of shutdown meets the dose rate limit of 2.5 µSv h -1 , at which point it is safe for workers to enter the treatment room area.
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Terapia por Captura de Neutrón de Boro , Método de Montecarlo , Terapia por Captura de Neutrón de Boro/métodos , Humanos , Análisis de Activación de Neutrones/métodos , Dosis de Radiación , Neutrones , Aceleradores de Partículas , Exposición Profesional/análisis , Dosificación RadioterapéuticaRESUMEN
We propose that several different reactor irradiation times followed by assaying of activity for differential counting periods may be employed for quality control (QC) of neutron activation analysis (NAA) data of biological samples. It is also recommended that three to four reference materials (RMs) of similar matrix but from different agencies such as National Institute of Standards and Technology (NIST, USA), International Atomic Energy Agency (IAEA, Vienna), Institute of Nuclear Chemistry and Technology (INCT, Poland), and National Institute of Environmental Studies (NIES, Japan) including a synthetic multielemental primary standard should always be analyzed simultaneously along with the samples. Finally, the mean ± σ values so obtained may be considered as more reliable after statistical analysis. Our analytical data for Na and K in three RMs (SRM 1572, CRM H-9, and Bowen's Kale) using different irradiation periods of 15 m, 2 h, 6 h, and 1 day were comparable with the certified values within error range of + 0.2 to - 2.7%. We report our data for 20 elements in two candidate RMs corn flour (INCT-CF-3) and soya bean flour (INCT-SBF-4) from the INCT, Poland, where Z-score values for most elements are in reasonable range of certified values.
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Irradiación de Alimentos , Nutrientes , Oligoelementos , Análisis de Activación de Neutrones , Nutrientes/análisis , Nutrientes/efectos de la radiación , Control de Calidad , Estándares de Referencia , Oligoelementos/análisis , Oligoelementos/efectos de la radiaciónRESUMEN
In this study, Instrumental Neutron Activation Analysis (INAA) was applied to study the elemental information of geological samples with the assistance of chemometric techniques. Samples of genuine Hetian Jade from Xijiang Province of China, counterfeit jade samples purchased at the neighborhood market, and granitoid samples from the same geographic location of genuine Hetian Jade were analyzed using INAA. The preliminary study indicates that INAA, with the help of principal component analysis (PCA), can be applied to obtain the multi-elemental concentrations of geological samples with high sensitivity, thereby effectively differentiating genuine Hetian Jade from counterfeit ones.
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Geología , Análisis de Activación de Neutrones , Análisis de Componente Principal , ChinaRESUMEN
The k0 standardization method is one of the most commonly used neutron activation analyses to determine the concentrations of elements in the sample. To perform this method, it is required to know the neutron spectrum parameters such as epithermal neutron flux shape factor (α) and thermal to epithermal neutron flux ratio (f). In this study, the α and f parameters were determined using the Cd-ratio dual monitor method and bare triple monitor method. In both methods, irradiation studies were performed in the central thimble at the ITU Triga Mark II research reactor. A gamma-ray counting system (HpGe detector) was used for measuring foil activation values. The selected monitors were 197Au and 94Zr for the Cd-ratio dual monitor method and 197Au/94Zr/96Zr for the bare triple monitor method. The α and f parameters were -0.221 ± 0.018 and 41.826 ± 4.701 for 197Au/94Zr (724 keV) monitors, -0.231 ± 0.019 and 42.626 ± 4.791 for 197Au/94Zr (756 keV) monitors, 0.228 ± 0.025 and 43.917 ± 3.596 for 197Au/94Zr/96Zr monitors, respectively.
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Cadmio , Neutrones , Análisis de Activación de Neutrones/métodos , Rayos gammaRESUMEN
In this work, prompt gamma ray neutron activation analysis technique was used to monitor the REEs saturation in resin. A facility consisted of a D-T neutron generator, a BGO detector and a 3He detector was established and applied to analyze REEs (Gd and Sm) samples. Neutron self-shielding effect was also corrected. The enriched Gd and Sm in resin were close to saturation at about 400 min. The results showed a satisfactory agreement with the XRF tests, which demonstrated that PGNAA was sufficient for monitoring REEs saturation in resin.
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Resinas de Intercambio Iónico , Metales de Tierras Raras , Estudios de Factibilidad , Análisis de Activación de Neutrones/métodos , NeutronesRESUMEN
It is well known that George Hevesy and Hilde Levi were the original discoverers of neutron activation analysis. However, there were many other researchers in Europe that firstly unknowingly and knowingly discovered the neutron, and others who experimented in neutron induced radioactivity. A historical timeline of the several parallel experiments in a very short period is given in this synopsis. It eventually was Hevesy and Hilde to first use the powerful technique of neutron activation analysis for analytical chemistry.
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Neutrones , Radiactividad , Europa (Continente) , Análisis de Activación de Neutrones/métodosRESUMEN
The prompt gamma-ray neutron activation analysis (PGNAA) is a significant technique for determining the quantities of a variety of elements in natural materials, whether online or in situ, regardless of their chemical compounds. This study focused on evaluating the performance of a portable PGNAA setup based on a Genie 16 DD neutron generator to determine the minimum detectable concentration (MDC) of nickel in soil samples. Two separate reaction mechanisms were used to activate the samples. A CeBr3 detector was used to detect nickel gamma rays at 1331 and 1454 keV caused by neutron inelastic scattering, as well as those at 8553 and 8998 keV emitted following thermal neutron capture activations. The obtained MDC values for both reaction channels have improved as a result of the research.
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Neutrones , Níquel , Rayos gamma , Análisis de Activación de Neutrones , SueloRESUMEN
The aim of this study was to use instrumental neutron activation analysis and multivariate analysis to determine the provenance of Jamaican Cannabis sativa L. Sixty-three samples were collected from various areas in Jamaica, with no other data but their known or self-reported growing regions. The samples were analysed for Al, As, Br, Ca, Cd, Co, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc, Sm, Sr, V, and Zn. The resulting elemental data were statistically evaluated using agglomerative hierarchical cluster analysis and principal component analysis. Cluster analysis was able to group the samples into their known or reported growing regions with a high degree of accuracy. Principal component analysis was also able to elucidate some of the underlying geochemical factors that could explain the clustering. These included the underlying bauxitic geochemistry and the influence of fertilizer inputs. Of the analysed elements, Al, As, Cd, Co, Fe, K, La, Mg, Mn, Sc, Sm, V, and Zn appear to be most significant in identifying the growing regions of the cannabis samples. Results indicate the promise of this methodology with an increased dataset and potentially further refinement of the identifying elements.
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Cannabis , Oligoelementos , Cadmio/análisis , Humanos , Jamaica , Análisis de Activación de Neutrones/métodos , Proyectos PilotoRESUMEN
The in-situ relative detection efficiency strongly influences the characteristics of the k0-based internal monostandard neutron activation analysis (IM-NAA). In the present work, various mathematical functions were explored for the establishment of in-situ relative detector efficiency calibration and compared their performance based on the reduced chi-square (χ2) values. Among the various mathematical functions, the polynomial logarithm with 6th order was found to be associated with the minimum mean standard deviation for the experimental data and the lowest value of reduced χ2 after carrying out multiple iterations using Nelder-Mead algorithm. Quality assurance of the function was tested by carrying out elemental quantification of the NIST SRM 1633b coal fly ash. Gamma energies of the activation products, 152mEu, 59Fe, 140La, 24Na and 46Sc of the irradiated NIST standard were used for the in-situ relative full energy peak efficiency calibration of 30% HPGe detector. The sample was counted for different time intervals for the complete profiling of the elements present in the NIST SRM. The deviations for most of the elements were found to be within ±5% with respect to the certified values and ξ-score values were within ±2, demonstrating its better accuracy. This method was also applied satisfactorily to profile the elemental concentrations of alloy materials used in a thermal sensor guide tube of the steam generator in a test reactor.
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Análisis de Activación de Neutrones , Calibración , Rayos gamma , Análisis de Activación de Neutrones/métodosRESUMEN
A new instrumental neutron activation analysis (INAA) for the simultaneous determination of titanium (TiO2) and silica (SiO2) dioxide as UV-filters in sunscreens is described. Samples are encapsulated, neutron irradiated (30 s) and after a suitable decay (3 min), the induced 51Ti (T1/2 = 5.76 min) and 29Al (T1/2 = 6.56 min) radionuclides are measured for the emitted γ-ray fingerprint. Three applications were carried out: (i) screening study (analysis of commercial sunscreens in combination with single particle inductively coupled plasma mass spectrometry (sp-ICP-MS); (ii) research study (development of innovative UV-filters such as titanium dioxide or bismuth titanate loaded inorganic mesoporous silica nanoparticles, MSN); (iii) validation study (intercalibration of a spectrochemical method - inductively coupled plasma optical emission spectrometry, ICP-OES). Collectively, the nuclear method appears a powerful tool adequate for quantifying TiO2 and SiO2 in the above studies. The limited accessibility at the nuclear reactor for neutron activation is probably one of the reasons why the excellent characteristics of the nuclear technique are not always fully known and exploited in the industrial and research chemical world.
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Nanopartículas , Protectores Solares , Nanopartículas/análisis , Análisis de Activación de Neutrones , Dióxido de Silicio , Titanio/análisisRESUMEN
Glass forensics is an important area in forensic crime investigations, wherein glass origin or source finding is necessary mainly through chemical composition. In the present work, Nuclear Analytical Techniques namely external (in air) Particle Induced Gamma-ray Emission (PIGE) and Instrumental Neutron Activation Analysis (INAA) were utilized for complete chemical characterization of twenty-five "as received" windshield glass samples of six car manufactures. Concentrations of four major elements (Si, Na, Mg and Al) by PIGE using proton beam and nineteen elements including sixteen trace elements by INAA using research reactor neutrons were determined. Both the methods were validated by analysing matrix matched glass certified (standard) reference materials. Trace elemental concentrations including rare earth elements (REEs) and ternary plot using concentrations of major, transition elements and REEs were utilized to obtain preliminary grouping of the analyzed glass samples. Statistical tools namely K-mean, Cluster Analysis and Principal Component Analysis (PCA) using trace elemental concentrations were utilized for grouping studies, important for forensic applications. Among these statistical analysis techniques, PCA results confirmed that windshield glasses from six manufactures clearly belong to six different groups.
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Oligoelementos , Automóviles , Vidrio , Iones , Análisis de Activación de Neutrones/métodosRESUMEN
Late Pleistocene hunter-gatherers in East Asia adopted pottery, yet the ability to reconstruct circulation, mobility, and exchange has been hampered, in part, due to problematic regional geochronology. The driving forces behind pottery adoption is unclear. The purpose of this study is to test our results of the first systematic petrographic pottery sourcing from the pre-Younger Dryas by utilizing neutron activation analysis. We examine samples from the Sankauyama I site on Tanegashima Island, southern Japan, dating to the Incipient Jomon, ca. 14,000/13,500-12,800 cal BP, with a well-defined geochronology. Our NAA results corroborate with the petrographic study suggesting that pottery was mainly produced in-situ, but some vessels were transported long distances from another island. Changing from high mobility, sedentary Incipient Jomon foragers made pottery, occasionally investing in long-distance ceramic vessel transportation and exchange likely involving ocean crossing. This may be associated with a risk-buffering strategy in the context of rising sea levels and isolation of Tanegashima.
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Arqueología , Cerámica , Asia Oriental , Japón , Análisis de Activación de NeutronesRESUMEN
Present study was aimed to investigate trace elemental composition and possible elemental correlation with depth of some Pakistani wells. Exploratory oil wells of Toot oilfield from Potwar region of upper Indus basin were selected for this purpose. Samples of well cuttings and soil sections were collected with the assistance of Oil and Gas Development Company Limited. Elemental analyses were performed using instrumental neutron activation analysis. This study is the first of its kind to report detailed elemental profile of Toot oilfield, Attock, Punjab, Pakistan, via instrumental neutron activation analysis (INAA). Source formation of Toot oilfield is characterized by Jurassic Datta formation. Around 19-26 elements were identified by INAA. Major, minor and trace elemental concentrations varied with depths along the sampling lines. Data analysis was performed by the application of principal component analysis (PCA). PCA was useful in differentiating between surface and depth samples. Elemental volumes of different wells were established through bi-plots. In extension, naturally occurring radioactive materials and technologically enhanced naturally occurring radioactive materials were also determined for the wells of Toot oilfield. Annual dose rates and activity levels were calculated in oil well formations. Measurements of annual dose rates fall within safe limits, indicating anodyne atmosphere. Contamination indices, such as enrichment factor with respect to Al, geo accumulation index (Igeo), pollution index and integrated pollution index, were also determined. Cr and Zn were found to cross the safe limits, which may be due to the local industrial and anthropogenic activities.
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Yacimiento de Petróleo y Gas , Espectrometría gamma , Monitoreo del Ambiente/métodos , Análisis de Activación de Neutrones , Pakistán , Suelo/químicaRESUMEN
Spices in general owned a very important reputation in the herbal plantae Kingdom; they have been used for food flavoring, preservation, aroma, and coloring for more than 2000 years. Moreover, spices are classified as all natural, and for this reason, they attracted a large scale of consumers worldwide; however, since most of spices are consumed in their natural form (without grounded them), it is necessary to monitor their consumed quantities. Hence, the aim of this work was to quantify major and trace elements contained in some Algerian kitchen frequently used spices (Piper nigrum L., Nigella sativa L., and Pimpinella anisum L.). Spice materials were washed well then pass through an instrumental neutron activation analysis (INAA). Results revealed the existence of twenty-six elements among them: K, Ca, Fe, and Na which showed significant concentrations, consecutively, while Ce, Eu, Lu, Sm, and Tb were presented at low concentrations. Furthermore, these spices consumption assessment results were found to be well below the tolerance limits compared with the recommended values (RDA) suggested by the FAO association.
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Especias , Oligoelementos , Argelia , Humanos , Análisis de Activación de Neutrones , Medición de Riesgo , Especias/análisis , Oligoelementos/análisisRESUMEN
Even when cultivated in uncontaminated soils, tobacco plant has higher propensity to extract and accumulate trace elements. The concentrations (mass fractions) of essential elements (K, Ca, Mg, Na, Cl, Mn, Fe, Cu, and Zn) and 28 non-essential elements in tobacco plant (leaves, stem, and root) of Northeast India and their respective soils were quantitatively measured. Hg mass fraction in all samples analyzed were found to be < 10 mg/kg. The heavy element mass fractions of tobacco are weakly correlated to different soil parameters. The bioconcentration factor values indicated that Cd (7) is selectively absorbed and translocated in the tobacco leaves compared to Zn (1.7), Cu (1.5), Ni (0.12), and Pb (0.1). Under acidic soil conditions, tobacco plant efficiently absorbed and translocated Cl- ion with great ease, whereas it may be a very low accumulator of rare-earth elements. The mass fractions of Mn, Cu, Sb, Cs, Rb, and Pb are very similar to the "reference plant," whereas significantly higher mass fractions of Al, Sc, Ti, Zr, Hf, Ta, Th, and U are present in the roots of tobacco plant relative to the "reference plant." Principal component analysis has revealed that Northeast Indian tobacco can be clearly differentiated from other varieties of tobaccos used in different countries because of their element profiles.
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Metales Pesados , Contaminantes del Suelo , Oligoelementos , Monitoreo del Ambiente/métodos , Plomo/análisis , Metales Pesados/análisis , Análisis de Activación de Neutrones , Suelo/química , Contaminantes del Suelo/análisis , Espectrofotometría Atómica , Nicotiana , Oligoelementos/análisisRESUMEN
Prompt gamma-ray neutron activation analysis method (PGNAA) was used to measure the talc content in flour. Neutron activation prompt gamma spectrum measured by NaI(Tl) detector has complex components, poor energy resolution, and high Compton plateau, how to obtain accurate element content from the prompt γ spectrum is one of the core problems of PGNAA. To reduce the systematic uncertainty caused by the variation of the neutron energy spectrum and γ self-absorption in different samples, the spectral decomposition method based on library least-squares was improved. As a result, the average relative deviation between the calculated values from measured spectra and the theoretical values based on the known composition was reduced from 6.1% to 0.3%. The relative uncertainty of 30 measurements on the same sample was reduced from 4.8% to 3.0%. The detection time can be reduced to 1 min, which meets the requirement of on-line measurement for talc in flour.