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This paper represents beach sand samples' natural and anthropogenic radionuclide concentrations and calculated external radiation dose levels. The radioactivity concentrations of eU (226Ra), eTh (232Th), 40K, and 137Cs were measured by gamma spectrometry using an HPGe detector. The activity concentrations ranged from 1.8 to 27.7 Bq kg−1, 5.7 to 19.5 Bq kg−1, 49.8 to 457.9 Bq kg−1, and 0.2 to 5.6 Bq kg−1 for eU, eTh, 40K and 137Cs, respectively. The radiological hazard parameters were compared to the international reference values. The results show that all data obtained are below the world average, meaning the radiation hazard is insignificant. [ABSTRACT FROM AUTHOR]

This study investigates the levels of natural and artificial radioactivity in rice samples collected from various local markets in Islamabad, Pakistan. The 226Ra, 232Th, and 40K activity concentrations were measured through gamma-ray spectrometry with a NaI(Tl) detector. The average activity concentrations were 1.67 ± 1.19 Bq kg−1 for 226Ra, 3.31 ± 1.83 Bq kg−1 for 232Th, and 88.51 ± 11.65 Bq kg−1 for 40K. Calculated radium equivalent (Raeq) values ranged from 7.35 to 18.08 Bq kg−1, with a mean value of 11.11 Bq kg−1, all below the permissible maximum of 370 Bq kg−1. The absorbed dose rates ranged from 6.85 to 16.39 nGy h−1, with an average of 10.64 nGy h−1, falling below the acceptable limit of 51 nGy h−1. The outdoor and indoor radiation hazard indices (Hex and Hin) had mean values of 0.03, both below the threshold value of one. The external and internal hazard indices (Iγ and Iα) were both 0.088, also below the critical value of one. The excess lifetime cancer risk (ELCR) ranged from 0.28 to 0.11, with a mean value of 0.18, which is less than the critical value of one. Overall, the radioactivity levels in the analyzed rice samples are within the acceptable limits set by the International Commission on Radiological Protection and are below global averages. These results offer important insights into the radiological safety of rice consumption in the study area. [ABSTRACT FROM AUTHOR]

Phosphogypsum (PG) is a solid by-product of the phosphate industry, rich in contaminants and produced in large quantities. Raw materials and stabilized specimens, consisting of bentonite-lime-PG mixtures, were characterized by mineralogical, microstructural, chemical, alpha-particle, and gamma-ray spectrometry analysis before hydration and after hardening. Compressive strength and leaching tests were performed on hardened specimens. The physicochemical parameters and chemical composition of leachates from raw materials and hardened specimens were determined. PG contains high concentrations of natural radionuclides, specially from U series. Uranium-238 activities are double in PG than the worldwide average for soil values. The mobility of PTEs from PG is Cd (2.43%), Zn (2.36%), Ni (2.07%), Cu (1.04%), Pb (0.25%), and As (0.21%). Cadmium is the cation most easily released by PG in water with a concentration 0.0316 mg kg−1. When PG is added to bentonite-lime mixture, cadmium is no longer released. The radionuclide 238,234U and 210Po predominates in the leachates of PG. However, the activity of 210Po becomes negligible in the leachates of bentonite-lime-PG mixtures. The addition of PG to bentonite-lime mixtures facilitates the trapping of trace elements (PTEs) and radionuclides, providing potential applications for PG as road embankments and fill coatings. [ABSTRACT FROM AUTHOR]

The process of radiological characterization involving all the systems, structures, equipment, and components resulting from the decommissioning of the VVR-S nuclear research reactor at the Horia Hulubei National Institute for Physics and Nuclear Engineering was a continuous journey marked by ongoing research, specialized training, and the accumulation of invaluable experience. Recognizing the significance of protecting the expertise gained during this effort, this paper aims to share several key insights collected from the radiological characterization process. In particular, the focus is placed on elucidating various methodologies and techniques utilized in gamma-ray spectrometry. The aim of delving into these specific aspects is to offer practical lessons that can serve as valuable guidance for future efforts in radiological characterization within similar contexts. Through the dissemination of these insights, it is hoped that the collective knowledge and expertise amassed during the radiological characterization of the VVR-S nuclear research reactor decommissioning can be effectively preserved and utilized for the benefit of future projects in the field. [ABSTRACT FROM AUTHOR]

In this paper, an assessment of the natural radioactivity level, radon exhalation, metal contamination, and mineralogy of a granodiorite rock sample from Stilo, in the Calabria region, Southern Italy is presented as a case study. This rock was employed as a building material in the area under study. The specific activity of 226Ra, 232Th and 40K natural radioisotopes was assessed through high-purity germanium (HPGe) gamma-ray spectrometry. Then, several indices such as the absorbed gamma dose rate (D), the annual effective dose equivalent (AEDE), the activity concentration index (ACI) and the alpha index (Iα), were quantified to determine any potential radiological health risk related to radiation exposure from the analyzed rock. Furthermore, E-PERM electret ion chambers and inductively coupled plasma mass spectrometry (ICP-MS) measurements were carried out to properly quantify the radon exhalation rate and any possible metal pollution, respectively. In particular, to further address metal pollution factors, the geo-accumulation index (Igeo) was calculated to properly address the toxicity levels of the ecosystem originating from the detected metals. Finally, with the aim of successfully discriminating the provenance of such naturally occurring radionuclides, a combined approach involving X-ray diffraction (XRD) and µ-Raman spectroscopy was employed for the identification of the main radioisotope-bearing minerals characterizing the investigated granodiorite. The results achieved in this case study can be taken as the basis for further inquiries into background levels of radioactivity and chemical contamination in natural stone employed as building materials. [ABSTRACT FROM AUTHOR]

Gamma emission induced by the irradiation of nickel and zirconium with fission neutrons was investigated with the FaNGaS (Fast Neutron–induced Gamma-ray Spectrometry) instrument operated at Heinz Maier-Leibnitz Zentrum. Measurements were done at an angle of 90° with respect to the direction of the fission neutron beam (average neutron energy of 2.18 MeV). We report on the relative intensities and production cross sections of 265 gamma lines (163 for nickel and 102 for zirconium). Consistency with available literature data was evaluated. The cross section of the 90Zr(n,n′)90mZr reaction was determined to be 88 ± 8 mb. For a counting time of 12 h, the detection limits of 0.7 and 1.3 mg were estimated for nickel and zirconium, respectively. [ABSTRACT FROM AUTHOR]

In this study, the current status of natural and artificial radioactivity levels in soil samples from the Büyükçekmece and Silivri districts of Istanbul, as well as the Marmara Ereğlisi district in Tekirdağ, has been determined in anticipation of a potential nuclear leakage (e.g. the Zaporizhzhia Nuclear Power Plant). Twenty soil samples were collected from the study area, and the radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs were measured using an HPGe detector. The average concentrations of 226Ra, 232Th, 40K and 137Cs were found to be 26 ± 2, 30 ± 2, 540 ± 29, 0.55 ± 0.07 Bq kg−1, respectively. [ABSTRACT FROM AUTHOR]

This study aims to assess the artificial and natural radiation dose levels in certain districts of Kocaeli province within the Marmara region, 37 years after the Chernobyl nuclear accident, and evaluate the current status prior to potential nuclear leakage events from Zaporijya or other nuclear power plants. Radioactive concentrations of 232Th, 238U, 40K and 137Cs were determined using HPGe gamma spectrometry in 26 soil samples collected from the region of interest. The average concentrations were found to be 22.35 Bqkg−1 for 238U, 26.36 Bqkg−1 for 232Th, 368.34 Bqkg−1 for 40K, and 2.44 Bqkg−1 for 137Cs. Furthermore, the study revealed an absorbed dose rate of 41.73 nGyh−1, an annual effective dose equivalent of 51.18 µSvy−1, and an excess lifetime cancer risk of 0.00018. [ABSTRACT FROM AUTHOR]

The objective of the research was to examine microbial characteristics, metabolites produced, and the potential radiological risks present in mining soils located in Keana, North Central Nigeria. Soil samples were collected from various locations within Keana, Nasarawa State. Bacterial isolation was carried out, and molecular techniques were employed to characterize the bacteria found in the collected soil samples. Additionally, the susceptibility of these isolates to antibiotics was determined, and the bacteria screened for their ability to produce metabolites. The isolated bacteria were classified into three groups: Actinobacteria, Firmicutes, and Proteobacteria. The analysis of the spectra revealed that 1595 compounds were produced, including carboxylic acids, nitro compounds, aldehydes, anhydrides, esters, ketones, amides, phenols, alcohols, alkanes, alkenes, alkynes, and arenes. Some of the metabolites produced were oleic acid, 1,3-dioxolane, linoelaidic acid and oleic acid, 1-nonadecene, butylated hydroxytoluene, diisooctyl phthalate, bis(2-ethylhexyl) phthalate among others, and 1,2-benzenedicarboxylic acid (85.32%) as the most produced metabolite. Among the antibiotics tested, levofloxacin and ciprofloxacin exhibited the strongest antibacterial properties against the isolates. Airborne gamma-ray spectrometry analysis identified elevated levels of potassium, thorium, and uranium in the soils, indicating potential environmental hazards. However, no significant correlation was found between the presence of bacteria and radioactive elements. These findings emphasize the importance of comprehensive environmental monitoring in Keana to address potential health risks associated with microbial contamination and radioactive materials. Additionally, the study highlighted the role of microbial diversity in Keana soils in promoting the production of secondary metabolites with potential applications in pharmaceutical and industrial sectors.. [ABSTRACT FROM AUTHOR]

Evaluating the natural radioactivity in construction materials is significant, particularly considering the prevailing belief that our homes offer the safest living environments. To investigate this, 38 samples of building materials were collected from highly populated residential areas within the Malappuram district in Kerala, India. The levels of naturally occurring radionuclides (226Ra, 232Th, and 40K) were quantified using a NaI (Tl) detector. Radiological indices, such as radium equivalent, absorbed dose rate, effective dose rate, hazard indices, alpha index, gamma index, and cancer risk, were calculated for the samples. The activity concentrations of 226Ra, 232Th, and 40K ranged from 8.84 ± 0.3 (flooring oxide) to 46.84 ± 2.11Bq/kg (rock samples), 11.84 ± 0.2 (pumice sample) to 130.21 ± 8Bq/kg (granite sample), and 58.63 ± 4 (pumice) to 1024.32 ± 22Bq/kg (granite) with an average of 25.80 ± 4.61, 55.05 ± 6.2, and 392.30 ± 16 Bq/kg. (average ± standard deviation), respectively. As a result, all of these computed parameters fell within safe limits. The examined building materials were found to have a negligible impact on radiation exposure, posing no significant radiation risks to residents. Researchers utilized statistical techniques to understand the interrelationships and similarities among radionuclides and radiological characteristics across samples, including Pearson correlation, principal component analysis, and cluster analysis. [ABSTRACT FROM AUTHOR]

Excitation functions of alpha-particle induced nuclear reactions on natSn have been presented in the 11–40 MeV energy range. In the present study, the stacked-foil activation technique followed by offline gamma-ray spectrometry was used to measure the production of 119Te, 121Te, 122Sb and 126Sb from alpha-particle induced reactions on natSn. The TALYS nuclear code was used to calculate the theoretical predictions of the excitation functions of natSn(α,x) nuclear reactions. The measured data of the above-mentioned nuclear reactions were compared with the theoretical predictions and the experimental results available from EXFOR. In this study, covariance analysis was performed to calculate the uncertainty propagation in the measured cross sections. [ABSTRACT FROM AUTHOR]

In this study, a comprehensive investigation was conducted to determine the radioactivity levels of naturally occurring radioactive materials (NORMs) in heap pads/soil and water samples within and around the operational area of Tarkwa Gold Mine in Ghana. Gamma-ray spectrometry was used to determine the activity concentrations of 238U, 232Th, and 40K in heap pads/soil, and 226Ra, 228Th, and 40K in water samples. The average activity concentrations of 226Ra and 228Th in all water samples were below the World Health Organisation (WHO) recommended guidelines for drinking water. Similarly, the average activity concentrations of measured radionuclides in heap pads/soil samples taken from depths of 0–20 cm and 20–50 cm were found to be below the worldwide average reported values. The annual effective dose to the public was estimated to be around 0.16 mSv, which is below the recommended limit. The values of the hazard indices are also below the recommended limits, implying that if heap pads/soils are used for building purposes and construction, they will not pose any significant radiation hazard. The results of this study indicate that radiation levels are within the natural background radiation levels reported in the literature and are consistent with findings from similar studies conducted in Ghana. [ABSTRACT FROM AUTHOR]

Vineyards hold considerable soil variability between regions and plots, and there is frequently large soil heterogeneity within plots. Clay content in vineyard soils is of interest with respect to soil management, environmental monitoring, and wine quality. However, spatially resolved clay mapping is laborious and expensive. Gamma-ray spectrometry (GS) is a suitable tool for predicting clay content in precision agriculture when locally calibrated, but it has scarcely been tested site-independently and in vineyards. This study evaluated GS to predict clay content with a site-independent calibration and four machine learning algorithms (Support Vector Machines, Random Forest, k-Nearest Neighbors, and Bayesian regulated neuronal networks) in eight vineyards from four German vine-growing regions. Clay content in the studied soils ranged from 62 to 647 g kg−1. The Random Forest calibration was most suitable. Test set evaluation revealed good model performance for the entire dataset with RPIQ = 4.64, RMSEP = 56.7 g kg−1, and R2 = 0.87; however, prediction quality varied between the sites. Overall, GS with the Random Forest model calibration was appropriate to predict the clay content and its spatial distribution, even for heterogeneous geopedological settings and in individual plots. Therefore, GS is considered a valuable tool for soil mapping in vineyards, where clay content and product quality are closely linked. [ABSTRACT FROM AUTHOR]

This study builds on a preliminary investigation into the efficacy of gamma radiation surveying as a complementary tool for archaeological prospection. Improved surveying and data processing methods were implemented, including the use of a vehicle‐mounted Groundhog surveying system, use of alternative software tools and examination of the impacts of individual radionuclides. The study focuses on a range of targets within Insulae VII, XXXV and XXXIII in Silchester Roman town, Hampshire. Targets of interest included a polygonal temple, a house, ditches (including an Iron Age defensive ditch) and several Roman roads. While the survey revealed no measurable differences in the gamma radionuclide content of less substantial structures (such as the temple and house) and the surrounding soil, it successfully delineated major structures. The Roman roads, Iron Age defensive ditch and potentially an indication of a historic field boundary not present in modern records were clearly visible in the generated visualisations. The roads and field boundary appear as distinct linear features of depleted radioactivity. The location of the Iron Age ditch correlates with an area of elevated radioactivity. Notably, the technique not only successfully identified archaeological features but was also able to indicate differences in the properties of similar targets such as variations in road thickness. Further, the gamma radiation data indicates variations in the local geology attributable to historic changes in land use and geochemical composition. This latest study corroborates the findings of the preliminary investigation, demonstrating replicability, scalability and ability to enhance output data quality. Further research, including sampling and non‐destructive analysis of materials from the site, is needed to better explain observed results. [ABSTRACT FROM AUTHOR]

Despite decades of effort, there remains an inability to measure snow water equivalent (SWE) at high spatial resolutions using remote sensing. Passive gamma ray spectrometry is one of the only well-established methods to reliably remotely sense SWE , but airborne applications to date have been limited to observing kilometre-scale areal averages. Noting the increasing capabilities of unoccupied aerial vehicles (UAVs) and miniaturization of passive gamma ray spectrometers, this study tested the ability of a UAV-borne gamma spectrometer and concomitant UAV-borne lidar to quantify the spatial variability of SWE at high spatial resolutions. Gamma and lidar observations from a UAV (UAV-gamma and UAV-lidar) were collected over two seasons from shallow, wind-blown, prairie snowpacks in Saskatchewan, Canada, with validation data collected from manual snow depth and density observations. A fine-resolution (0.25 m) reference dataset of SWE , to test UAV-gamma methods, was developed from UAV-lidar snow depth and snow survey snow density observations. The ability of UAV-gamma to resolve the areal average and spatial variability of SWE was promising with appropriate flight characteristics. Survey flights flown at a velocity of 5 ms-1 , altitude of 15 m , and line spacing of 15 m were unable to capture the average or spatial variability of SWE within the uncertainty of the reference dataset. Slower, lower, and denser flight lines at a velocity of 4 ms-1 , altitude of 8 m , and line spacing of 8 m were able to successfully observe areal average SWE and its variability at spatial resolutions greater than 22.5 m. Using a combination of UAV-based gamma SWE and UAV-based lidar snow depth improved the spatial representation of SWE substantially and permitted estimation of SWE at a spatial resolution 0.25 m with a ± 14.3 mm error relative to the reference SWE dataset. UAV-borne gamma spectrometry to estimate SWE is a promising and novel technique that has the potential to improve the measurement of shallow prairie snowpacks, and when combined with UAV-borne lidar snow depths, can provide fine-resolution, high-accuracy estimates of prairie SWE. Research on optimal hardware, data processing, and interpolation techniques is called for to further improve this remote sensing product and explore its application in other environments. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This study measured the naturally occurring radionuclides (238U, 232Th, and 40K) in sixteen selected soils samples of Irele local government area in Ondo state, southwestern Nigeria using a thallium-doped sodium iodide gamma-ray spectrometry detector. The values of concentration of natural radionuclides in the soils ranged from 16.18–32.16 with a mean value of 27.58 Bq.kg−1, 10.38–24.15 with a mean value of 16.92 Bq.kg−1, and 321.13–528.18 with a mean value of 423.05 Bq.kg−1 for 238U, 232Th, and 40K, respectively. The values of the assessed radiological parameters (absorbed gamma dose rate in air, annual effective dose rate, radium equivalent activity, and the external hazard index) are found to range from 30.81–47.11 with a mean value of 40.60 nGy.h−1, 0.19–0.29 with a mean value of 0.25 mSv.y−1, 62.53–98.25 with a mean value of 84.35 Bq.kg−1 and 0.17–0.27 with a mean value of 0.23, respectively. The obtained values are lower than the recommended world average of 33, 45, and 450 Bq.kg−1 for 238U, 232Th, and 40K published by the United Nations Scientific Committee on the Effects of Atomic Radiation and the National Council on Radiation Protection and Measurement. [ABSTRACT FROM AUTHOR]

This article discusses the use of X-ray fluorescence analysis (RFA) and gamma spectroscopy as analytical techniques in chemistry education. The experiments described in the article focus on exploring atomic models and characterizing different materials. RFA is used to determine the composition of compounds and metals, while gamma spectroscopy can detect gamma radiation emitted by isotopes. The article provides examples of using these techniques to analyze specific materials, such as coins and white pigments. The authors suggest that the benefits of these techniques justify the cost of acquiring the necessary equipment. [Extracted from the article]

This study aimed to estimate the, exhalation rate, and natural radioactivity in the soil of Roopnagar district, Punjab. The radon mass and surface exhalation rate ranged from 1.18 mBq kg−1 h−1 to 5.72 mBq kg−1 h−1, with an average value of 2.68 mBq kg−1 h−1, and from 4.89 mBq m−2 h−1 to 23.58 mBq m−2 h−1, with an average value of 11.09 mBq m−2 h−1, respectively. The activity concentration of 226Ra, 232Th, and 40K was found to be 31.9 Bq kg−1, 44.1 Bq kg−1, and 419.0 Bq kg−1, respectively. The air absorbed dose rates of radionuclides 226Ra, 232Th, and 40K had an average value of 14.88 nGyh−1, 27.4 nGyh−1, and 5.89 nGyh−1, respectively. The total air absorbed dose from all radionuclides ranged from 19.5 nGyh−1 to 87.7 nGyh−1, with an average value of 48.1 nGyh−1, which is discovered to be well below the levels considered dangerous by the United Nations Scientific Committee on the Effects of Atomic Radiations. [ABSTRACT FROM AUTHOR]

The main objective of this study was to assess the natural radiation dose and radiological risk around Lake Monoun and some surrounding localities. A total of 28 soil samples were analyzed using gamma-ray spectrometry based on a High-Purity Germanium detector. The activity concentrations of primordial radionuclides (226Ra, 232Th, and 40K) and the corresponding health hazard risks were determined. The average value of air absorbed dose rate and the total excess lifetime cancer risk were found to be 68.32 nGyh−1 and 1.86 × 10–3. These recorded average values were above the world average value reported by UNSCEAR 2000. RESRAD-OFFSITE computer code was used to evaluate the long-term radiological risk from the study area. The RESRAD simulation data of excess cancer risk was above the world limit of 1.45 × 10–3 until 100 years. The obtained results showed insight into public exposure and could be used as baseline data for future investigations. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the levels of radioactivity, radiological doses and the increased lifetime risk of cancer of radionuclides contained in soils collected from the territory of Shumen Plateau Nature Park, (North-Eastern Bulgaria). A gamma spectrometric system was used to estimate the natural radionuclides. The average values for the specific activities for 238U, 232Th, 40K measured in soils were 28.65 ± 4.30 Bq/kg, 18.86 ± 2.83 Bq/kg and 609.09 ± 91.36 Bq/kg, respectively. Only the average value for 40K was higher than the documented worldwide values of, respectively 35 Bq/kg, 30 Bq/kg and 400 Bq/kg. We calculated the average values for assessing radiological hazards: radium equivalent activity 102.52 Bq/kg, external hazard index 0.28 Bq/kg, internal hazard index 0.35 Bq/kg, absorbed gamma dose rate in air 52.04 nGy/h, annual effective dose rate 0.32 mSv/y, total excess lifetime cancer risk 1.95 × 10-3 and radioactivity level index 0.79 mSv. The average values we obtained for radiological indices and specific activities are lower than the global average values quoted in UNSCEAR 2000. [ABSTRACT FROM AUTHOR]

This study used gamma ray spectrometry to determine the radiological safety of construction soil sampled randomly from Mbeere North region, Kenya. The mean activity concentration of 232Th, 238U, and 40K was 149.7 ± 2.8 Bqkg−1, 88.3 ± 2.4 Bqkg−1, and 490 ± 35 Bqkg−1, respectively. These averages exceed the world average for all the radionuclides. The radionuclides were non-uniformly distributed, with higher concentrations along the slopes and on the feet of the hills. The mean absorbed dose rate, indoor and outdoor annual effective dose, radium equivalent, external hazard index, and internal hazard index were 157.9 ± 4.4 nGh−1, 0.58 ± 0.02 mSvy−1, 0.39 ± 0.01 mSvy−1, 340.7 ± 9.2 Bqkg−1, 0.92 ± 0.02 and 1.14 ± 0.03, respectively. Among the radiation safety indicators, only the average internal hazard index exceeded slightly the acceptable safe limit. Therefore, soils of Mbeere North region are radiologically safe for use in brick making and construction of human habitats. [ABSTRACT FROM AUTHOR]

Introduction: This study aims to evaluate the potential radiological hazard associated with the consumption of water and fish products from Ero Dam. Material and Methods: The activity concentrations of 238U, 232Th and 40K in the samples were determined using gamma ray spectrometry. Results: Mean activity concentrations of 238U, 232Th and 40K in water were 8.49±1.38, 4.12±0.40 and 150.99±10.80 Bq/l respectively. In Oreochromis niloticus and Chrysichthys nigrodigitatus mean specific activity were 23.17±7.25, 14.25±1.60, 740.86±55.00 Bq/kg and 77.92±18.79, 16.26±1.63, 842.90±62.87 Bq/kg respectively. Average annual effective dose for water (Hw) was 1.58 mSv/yr and for fish edible tissue (Hf) 0.16 mSv/yr. Mean concentrations of 232Th and 40K in water are 312% and 1400% higher than guidance levels and mean specific activity for 238U and 232Th in fish were about three orders of magnitude higher than reference values. Mean Hw is about 1500% higher than the reference level and the average Hf for fish is 540% higher than the recommended Hf for natural radionuclides in fish products. Mean ELCR from consumption of water, Oreochromis and Chrysichthys are 1900%, 62% and 131% higher than the world's average value from carcinogens respectively. Conclusion: Continuous consumption of water and fish products from Ero Dam is associated with potential radiation risks. [ABSTRACT FROM AUTHOR]

Background: The alpha emitter astatine-211 (211At) is garnering attention as a novel targeted alpha therapy for patients with refractory thyroid cancer resistant to conventional therapy using beta emitter radioiodine (131I). Herein, we aimed to establish a robust method for the manufacturing and quality control of [211At]NaAt solution for intravenous administration under the good manufacturing practice guidelines for investigational products to conduct an investigator-initiated clinical trial. Results: 211At was separated and purified via dry distillation using irradiated Bi plates containing 211At obtained by the nuclear reaction of 209Bi(4He, 2n)211At. After purification, the 211At trapped in the cold trap was collected in a reaction vessel using 15 mL recovery solution (1% ascorbic acid and 2.3% sodium hydrogen carbonate). After stirring the 211At solution for 1 h inside a closed system, the reaction solution was passed through a sterile 0.22 μm filter placed in a Grade A controlled area and collected in a product vial to prepare the [211At]NaAt solution. According to the 3-lot tests, decay collected radioactivity and radiochemical yield of [211At]NaAt were 78.8 ± 6.0 MBq and 40 ± 3%, respectively. The radiochemical purity of [211At]At− obtained via ion-pair chromatography at the end of synthesis (EOS) was 97 ± 1%, and remained > 96% 6 h after EOS; it was detected at a retention time (RT) 3.2–3.3 min + RT of I−. LC-MS analysis indicated that this principal peak corresponded with an astatide ion (m/z = 210.988046). In gamma-ray spectrometry, the 211At-related peaks were identified (X-ray: 76.9, 79.3, 89.3, 89.8, and 92.3 keV; γ-ray: 569.7 and 687.0 keV), whereas the peak at 245.31 keV derived from 210At was not detected during the 22 h continuous measurement. The target material, Bi, was below the 9 ng/mL detection limit in all lots of the finished product. The pH of the [211At]NaAt solution was 7.9–8.6; the concentration of ascorbic acid was 9–10 mg/mL. Other quality control tests, including endotoxin and sterility tests, confirmed that the [211At]NaAt solution met all quality standards. Conclusions: We successfully established a stable method of [211At]NaAt solution that can be administered to humans intravenously as an investigational product. [ABSTRACT FROM AUTHOR]

The distribution of natural series radionuclides 226Ra, 232Th and non-series 40K in the heavy mineral-rich beach sands of highly touristic areas of Cox's Bazar sea beach has been studied. The study is made to evaluate the gamma radiation exposure to individuals with an aim to establish reference data for the presence of naturally occurring radionuclides. The present study reports the probable first attempt of detail and systematic work in the study areas for estimation of activity concentration in the recent beach sand samples. Radiometric analysis was performed using gamma ray spectroscopy system based on HPGe detector. The mean activity levels of 226Ra, 232Th and 40K in Laboni beach sands were ranged from 255.69±64.57, 336.83±93.96 and 1785.91±89.60 Bq kg-1, respectively. While in Kolatoli beach sands, the respective values were 166.42±35.99, 157.35±35.90 and 1894.42±74.07Bq kg-1, respectively. The mean values of 226Ra and 232Th concentrations in the investigated beach sands were estimated to be very much higher than the corresponding world average values and comparable to those found in high background radiation areas in the world. The heavy minerals seem to control the activity concentrations of 226Ra and 232Th in sand samples, showing some variances based on uranium and thorium bearing minerals. Various radiation health hazard indicators were found to be extremely higher when compared to the recommended values. Hence, heavy mineral-rich sands may pose a significant radiological health risk to the people. The descriptive statistics indicating the radionuclides of 226Ra, 232Th and 40K are uniformly and symmetrically distributed in the Cox's bazar beach sand. Multivariate statistical analysis showing the radioactivity and estimated radiological parameters are strongly positively correlated with 226Ra and 232Th, while weakly correlated with 40K, signifying that radiological risk is mainly associated and controlled by the radioactivity levels of uranium and thorium series radionuclides. [ABSTRACT FROM AUTHOR]

This article presents the Gamma-Ray Spectrometry (GRS) measurements of 32 fossil samples from the Museum of Natural Sciences of Guarapuava-PR, Brazil. GRS, without strict control of the measurement geometry, can serve as a complementary technique that gives results related to the total chemical and mineralogical composition of the pieces. In the case of fossils, GRS data may be interpreted to provide information about some diagenesis processes (mineralization) and the redox conditions of the sedimentary environment in which they were formed. The results demonstrated the feasibility of characterizing fossil samples with irregular geometries and varied densities using gamma ray spectrometry. [ABSTRACT FROM AUTHOR]

This paper propose a binomial distribution model based on Bayesian statistics in the field of monitoring artificial radionuclides. A multi time-interval analysis method is adopted to extract the 214Bi–214Po correlated events counts in the 222Rn decay series. Then the model evaluates natural background using the ratio of correlated events counts to total α counts. The Beta distribution is used as the prior distribution of this model. We detailed discussed the process of posterior estimation, and compared the new approach with the conventional approaches. The results show the new approach has a more sensitive response to artificial radionuclides. [ABSTRACT FROM AUTHOR]

This study explores the impact of integrating varying concentrations of Erbium Oxide (Er 2 O 3) into Oxide Dispersion Strengthened (ODS) alloys, specifically focusing on gamma-ray and neutron attenuation properties. Utilizing a 316L stainless steel matrix, Er 2 O 3 was methodically incorporated in concentrations ranging from 1 % to 21 % by weight. The structural and radiation attenuation properties of the resultant alloys were comprehensively analyzed using techniques such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and experimental gamma-ray transmission studies. The results demonstrate a significant enhancement in gamma-ray shielding with increased Er 2 O 3 content. This enhancement is quantitatively evidenced by increased linear attenuation coefficient, elevated effective Electron Density (Neff), reduced Half-Value Layers (HVL), and higher effective atomic numbers (Zeff). These findings are crucial for nuclear applications where efficient gamma-ray shielding is paramount. Conversely, a decrease in the effective removal cross section (Σ R) for neutron attenuation was observed with higher Er 2 O 3 concentrations. This suggests a potential compromise in neutron shielding efficiency, attributed to the dilution of neutron-absorbing base elements in the alloy. Additionally, the study reveals notable changes in the microstructural properties of the alloys, including alterations in particle size, distribution, and agglomeration, influenced by varying Er 2 O 3 concentrations. In conclusion, this research provides valuable insights into the design of ODS alloys for nuclear radiation shielding, highlighting the balance between gamma-ray attenuation and neutron shielding properties. The study's findings contribute to the development of advanced materials for safer and more efficient nuclear technology applications. [ABSTRACT FROM AUTHOR]

Characterization of synthetic and natural melanin nanoparticles (MNPs) has been challenging due to the variability of properties and chemical bonding. Although eumelanin was the first to be discovered, four additional subcategories of melanin now exist including pheomelanin, neuromelanin, allomelanin and pyomelanin. Mass spectrometry (MS) methods have provided crucial insights into the bonding, structure, and mechanism regarding MNP formation, but inconsistent findings in the literature have caused further confusion in the analysis and structure of MNPs. This mini‐review will focus on the types of MS experiments that have been used to analyze MNPs and what kind of information can be gained from different ionization sources, collisional activation experiments, and reaction monitoring quantitative methods when analyzing different subcategories of MNPs. Additionally, future directions regarding alternative applications of MNPs in MS experiments, mass defect analyses of complex mixtures, and a standardized nomenclature for isomeric redox states will all be addressed. © 2023 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Rationale: High costs and student numbers can often hinder implementation of mass spectrometry (MS) in the undergraduate teaching laboratory, often with technicians running samples on students' behalf, and the implementation of MS only in discrete or isolated experiments. This study explores the use of atmospheric solids analysis probe MS (ASAP‐MS) as a relatively low‐cost, benchtop instrument, and its potential for application as a 'bolt‐on' to existing undergraduate organic chemistry experiments. Methods: Thirteen products synthesised in undergraduate laboratory experiments were analysed by ASAP‐MS, along with their starting materials. Analysis was carried out with a Waters RADIAN ASAP mass spectrometer, at four different cone voltages simultaneously to provide fragmentation information. Results: Out of the 13 undergraduate experiments, ASAP‐MS was shown to be complementary in 11 of these, either through simple analysis of the precursor ion or by a more complex analysis of the fragments. Conclusions: ASAP‐MS provided spectra that both complement and enhance intended learning outcomes in existing organic chemistry experiments, showing its versatility as a bolt‐on technique. Moving forward, ASAP‐MS will be integrated into the University of Surrey's undergraduate teaching laboratory. [ABSTRACT FROM AUTHOR]

Radioactive particles often contain very high radioactivity concentrations and are widespread. They pose a potential risk to human health and the environment. Their detection, quantification, and characterization are crucial if we are to understand their impact. Here, we present the use of a real-time autoradiography gaseous detector (using parallel ionization multiplier) to expedite and improve the accuracy of radioactive particle screening in complex environmental samples. First, standard particles were used to assess the detector capabilities (spatial resolution, spectrometry, and artefact contributions), then, we applied the technique to more complex and environmentally relevant samples. The real-time autoradiography technique provides data with a spatial resolution (≲100 µm) suitable for particle analysis in complex samples. Further, it can differentiate between particles predominantly emitting alpha and beta radiation. Here, the technique is applied to radioactive cesium-rich microparticles collected from the Fukushima Daiichi nuclear exclusion zone, showing their accurate detection, and demonstrating the viability of real-time autoradiography in environmental scenarios. Indeed, for more complex samples (radioactive particles in a less radioactive heterogeneous background mix of minerals), the technique permits relatively high selectivity for radioactive particle screening (up to 61.2% success rate) with low false positive percentages (~ 1%). [ABSTRACT FROM AUTHOR]

Qualitative and quantitative tests of gemstones and diamonds are routinely performed nondestructively in the laboratory of Gemmological Institute of India (GII), Mumbai, India. Qualitative tests are based on microscopic examination. Energy Dispersive X‐Ray Fluorescence (EDXRF) spectrometry is used in the laboratory for quantitative analysis of elements. However, in some cases like determination of trace levels of cubic zirconia (CZ) in diamond powder, it is difficult to estimate simultaneously both CZ and diamond powder directly using EDXRF method. In view of this, a method was developed for estimation of ZrO2 present at low levels in diamond powder. In this method, EDXRF spectra of a series of simulated mixtures containing ZrO2 were measured. Peak areas under the characteristic Kα x‐ray of Zr (15.7 keV) in each mixture were computed and, a calibration plot was made between the peak areas and % fractions of ZrO2. From the calibration plot, a dynamic range of 0.1%–10% was obtained. From XRF spectra of the test sample, in duplicate, of diamond powder, Zr was estimated using the peak area and the percentage fraction was found to be 0.181 ± 0.020. Neutron activation analysis (NAA) was used for method validation with the same set of simulated samples used in EDXRF analysis. Results obtained by both the methods are found to be in good agreement and this newly developed method based on EDXRF spectrometry is in regular use in GII. [ABSTRACT FROM AUTHOR]

This investigation explores the potential of plasma lipidomic signatures for aiding in the diagnosis of Multiple Sclerosis (MS) and evaluating the clinical course and disease activity of diseased patients. Plasma samples from 60 patients with MS (PwMS) were clinically stratified to either a relapsing-remitting (RRMS) or a chronic progressive MS course and 60 age-matched controls were analyzed using state-of-the-art direct infusion quantitative shotgun lipidomics. To account for potential confounders, data were filtered for age and BMI correlations. The statistical analysis employed supervised and unsupervised multivariate data analysis techniques, including a principal component analysis (PCA), a partial least squares discriminant analysis (oPLS-DA) and a random forest (RF). To determine whether the significant absolute differences in the lipid subspecies have a relevant effect on the overall composition of the respective lipid classes, we introduce a class composition visualization (CCV). We identified 670 lipids across 16 classes. PwMS showed a significant increase in diacylglycerols (DAG), with DAG 16:0;0_18:1;0 being proven to be the lipid with the highest predictive ability for MS as determined by RF. The alterations in the phosphatidylethanolamines (PE) were mainly linked to RRMS while the alterations in the ether-bound PEs (PE O-) were found in chronic progressive MS. The amount of CE species was reduced in the CPMS cohort whereas TAG species were reduced in the RRMS patients, both lipid classes being relevant in lipid storage. Combining the above mentioned data analyses, distinct lipidomic signatures were isolated and shown to be correlated with clinical phenotypes. Our study suggests that specific plasma lipid profiles are not merely associated with the diagnosis of MS but instead point toward distinct clinical features in the individual patient paving the way for personalized therapy and an enhanced understanding of MS pathology. [ABSTRACT FROM AUTHOR]

During TRIGA reactor operation significant amounts of liquid radioactive waste are generated requiring appropriate management to ensure their safe disposal. Radiological characterization is an important activity needed to accomplish the waste acceptance criteria for different management steps including disposal. The purpose of this paper is to assess the activity concentrations of the ³1H. 383890Sr, 63286328Ni(difficult-to-measure), and gamma emitters (easy-to-measure) radionuclides in liquid radioactive waste generated by the TRIGA reactor operation and to establish a correlation among them to determine the scaling factors for this waste category. The radiological protocols applied for 6328Niand 3890Sr, separation and purification involve extraction chromatography using selective resins, while for H separation the distillation technique was applied. The assessment of gamma emitters was carried out using gamma-ray spectrometry and the detection of ³1H. 3890Sr, and 6328Niwas performed by liquid scintillation counting. The chemical yield of each experiment was determined by measuring the carrier added in each test by inductively coupled plasma optical emission spectrometry. The activity concentrations of 3890Sr, and 6328Niobtained were correlated with the activity concentration of 3860Co for establishing the scaling factor for the liquid radioactive waste stream. There were obtained good correlations but more experimental data are needed to determine the relevant scaling factors for these difficult-to- measure radionuclides. The scaling factors, once established, will improve and optimize the radiological characterization methodology applied for liquid radioactive waste as an easy and rapid method for assessment of concentration activities of difficult-to-measure radionuclides. Until now, no scaling factors data were reported for this liquid radioactive waste generated by TRIGA reactor operated by Institute for Nuclear Research Pitesti. The results obtained in this work represent preliminary data for establishing correlations between difficult-to-measure and easy-to-measure radionuclides and will be used for developing a scaling factor methodology. This will further be used to determine the inventory of difficult- to-measure radionuclides in different waste streams generated by TRIGA operation and decommissioning (foreseen after 2035). [ABSTRACT FROM AUTHOR]

Banana, a staple food, could be consumed daily for its nutritional value. In the present study, banana samples were collected from Kerala and Delhi NCR and gross beta-gamma activities (Bq kg−1) were estimated in order to understand the contribution of radiation levels to human body due to consumption of banana. Activities of radionuclides such as 40K and 232Th in banana samples were measured using gamma ray spectrometry. Effective dose rate by ingestion to an individual from banana consumption was determined and results were compared with the effective dose rate to general public by International Commission on Radiological Protection recommendations. [ABSTRACT FROM AUTHOR]

Gamma-ray spectroscopy is an effective technique for radioactive material characterization, routine inventory verification, nuclear safeguards, health physics, and source search scenarios. Gamma-ray spectrometers typically cannot be operated in the immediate vicinity of nuclear reactors due to their high flux fields and their resulting inability to resolve individual pulses. Low-power reactor facilities offer the possibility to study reactor gamma-ray fields, a domain of experiments hitherto poorly explored. In this work, we present gamma-ray spectroscopy experiments performed with various detectors in two reactors: The EPFL zero-power research reactor CROCUS, and the neutron beam facility at the Ohio State University Research Reactor (OSURR). We employed inorganic scintillators (CeBr3), organic scintillators (trans-stilbene and organic glass), and high-purity germanium semiconductors (HPGe) to cover a range of typical—and new—instruments used in gamma-ray spectroscopy. The aim of this study is to provide a guideline for reactor users regarding detector performance, observed responses, and therefore available information in the reactor photon fields up to 2 MeV. The results indicate several future prospects, such as the online (at criticality) monitoring of fission products (like Xe, I, and La), dual-particle sensitive experiments, and code validation opportunities. [ABSTRACT FROM AUTHOR]

The Kanyakumari coast is known to be a high background natural radiation area due to the placer deposits of heavy minerals such as ilmenite, monazite, and rutile. The Kanyakumari river sediments that could be the source of the elevated amounts of natural radionuclides in the coastal sands have been studied in this paper. The activity concentrations of primordial radionuclides 226Ra, 232Th, and 40K were determined using high-purity germanium (HPGe) gamma-ray spectrometry. The mean activity concentrations of 226Ra, 232Th, and 40K were found to be 75 Bq kg−1, 565 Bq kg−1, and 360 Bq kg−1, respectively. The mean absorbed dose rate was 395 nGy h−1. Radiological hazard parameters were studied and compared with the world average values. The contribution of 232Th to the total dose rate was found to be higher than that of the two other radionuclides. The high mean ratio of 232Th/226Ra suggested an enrichment of 232Th and the occurrence of 226Ra leaching due to an oxidizing environment. Principal component analysis (PCA) was carried out for the radionuclides in order to discriminate the source of the sediments. This study provides new insights into the distribution of natural radionuclides in sediments of rivers and streams. [ABSTRACT FROM AUTHOR]

Xenon (Xe) is a noble gas and therefore chemically inert in the environment. The Earth's atmosphere contains approximately 0.087 ppm of stable xenon. Radio xenon isotopes like 133Xe and 135Xe are artificial isotopes generated from various nuclear facilities. Atmospheric measurement of radioactive xenon isotopes (radio xenon) plays a key role in remote monitoring of any nuclear accidents, abnormal release from nuclear facilities or nuclear explosions, since radio xenon has a high capability to migrate in a wide range from the site. The measurement of these gamma-emitting radioxenon gas can be done by sampling the gas in measurement geometry (like gas cell) and counting the cell in suitable gamma spectrometry-based detector system. For measurement of radioactive content in the sample, the efficiency calibration of system has to be carried out with same measurement geometry and same gamma ray energy that of sample. Many times, the radioactive standard sources in same measurement geometries and for same gamma energies are not feasible. In such cases, experimentally validated computational techniques are used for generating efficiency function. This paper describes the application of computational technique for measurement of radio xenon (133Xe and 135Xe) gas in the environment. [ABSTRACT FROM AUTHOR]

Radioactivity measurements for water, sediment, microbial films and the bioaccumulation of radionuclides by extremophiles from hypersaline lakes and hot springs were carried out as scarcity studies in the Siwa Oasis, Egypt. Natural and man-made radionuclides were measured using high-resolution γ-spectrometry. Different radionuclides behaved differently in different environmental samples, while radionuclides were higher in microbial films compared to sediment, but all radionuclide levels except 226Ra in water were generally low. Microbial films from hypersaline lakes had higher concentrations of 40K, while microbial films from freshwater hot springs had the highest concentrations of 226Ra, 232Th and 137Cs. The calculated radiological hazard index parameters of radium equivalent activity (Raeq), absorbed dose rate (D), annual effective dose (AED) and external hazard (Hex) in the sediment were within acceptable limits, but were higher in the microbial film samples. Otherwise, the potential cancer risk of the three freshwater springs was 0.00244 ± 0.000293, 0.00135.6 ± 0.000172 and 0.00155.2 ± 0.000198. In addition, the bioaccumulation factor for microbial films indicated that they are good accumulators of radionuclides, especially for 226Ra and 232Th, which may contribute to their effectiveness in removing radionuclides from ecosystems. [ABSTRACT FROM AUTHOR]

With its high resolving power and sensitivity, mass spectrometry is considered the most informative technique for metabolite qualitation and quantification in the plant sciences. However, the spatial location information, which is crucial for the exploration of plant physiological mechanisms, is lost. Mass spectrometry imaging (MSI) is able to visualize the spatial distribution of a large number of metabolites from the complex sample surface in a single experiment. In this paper, a flexible and low-cost laser desorption–dielectric barrier discharge ionization-MSI (LD-DBDI-MSI) platform was constructed by combining an LD system with an in-line DBDI source, a high-precision sample translation stage, and an ambient mass spectrometer. It can be operated at a spatial resolution of 20 μm in an atmospheric environment and requires minimal sample preparation. This study presents images of in-situ metabolic profiling of two kinds of plants from different origins, a wild and a farmed Rheum palmatum L. From the screen of these two root sections, the wild one presented five more endogenous molecules than the farmed one, which provides information about the differences in metabolomics. [ABSTRACT FROM AUTHOR]

Background: Dementia and mild cognitive impairment are characterised by symptoms of cognitive decline, which are typically assessed using neuropsychological assessments (NPAs), such as the Mini-Mental State Examination (MMSE) and Frontal Assessment Battery (FAB). Magnetoencephalography (MEG) is a novel clinical assessment technique that measures brain activities (summarised as oscillatory parameters), which are associated with symptoms of cognitive impairment. However, the relevance of MEG and regional cerebral blood flow (rCBF) data obtained using single-photon emission computed tomography (SPECT) has not been examined using clinical datasets. Therefore, this study aimed to investigate the relationships among MEG oscillatory parameters, clinically validated biomarkers computed from rCBF, and NPAs using outpatient data retrieved from hospital records. Methods: Clinical data from 64 individuals with mixed pathological backgrounds were retrieved and analysed. MEG oscillatory parameters, including relative power (RP) from delta to high gamma bands, mean frequency, individual alpha frequency, and Shannon's spectral entropy, were computed for each cortical region. For SPECT data, three pathological parameters--'severity', 'extent', and 'ratio'--were computed using an easy z-score imaging system (eZIS). As for NPAs, the MMSE and FAB scores were retrieved. Results: MEG oscillatory parameters were correlated with eZIS parameters. The eZIS parameters associated with Alzheimer's disease pathology were reflected in theta power augmentation and slower shift of the alpha peak. Moreover, MEG oscillatory parameters were found to reflect NPAs. Global slowing and loss of diversity in neural oscillatory components correlated with MMSE and FAB scores, whereas the associations between eZIS parameters and NPAs were sparse. Conclusion: MEG oscillatory parameters correlated with both SPECT (i.e. eZIS) parameters and NPAs, supporting the clinical validity of MEG oscillatory parameters as pathological and symptomatic indicators. The findings indicate that various components of MEG oscillatory characteristics can provide valuable pathological and symptomatic information, making MEG data a rich resource for clinical examinations of patients with cognitive impairments. SPECT (i.e. eZIS) parameters showed no correlations with NPAs. The results contributed to a better understanding of the characteristics of electrophysiological and pathological examinations for patients with cognitive impairments, which will help to facilitate their co-use in clinical application, thereby improving patient care. [ABSTRACT FROM AUTHOR]

Mobile proximal gamma-ray spectrometry (GS) is an emerging approach to estimate soil texture directly in the field. It relies on gamma radiation emitted during the natural decay of potassium-40 (K-40) and other isotopes. The K-40 counts are correlated with total K content, mineralogical soil composition and therefore with soil texture. Yet, it is not clear if K fertilisation impacts the ratio of K-40 to total K which would necessitate to take the fertilisation history into account for soil sensing applications. To elucidate this question, a well-documented long-term experiment was selected. The soils of the Rengen grassland experiment (55 plots) were investigated for total K (XRF-K) and for K-40 via mobile proximal GS. No significant differences in XRF-K and K-40 were found between the treatments with and without K fertilisation, although formely published results point to negative and positive K balances, respectively. Fertiliser analysis revealed a ratio of K-40 to total K that was almost identical to the natural abundance of 0.0117%. It was concluded that it is not necessary to take K fertilisation history into account when predicting soil texture from mobile proximal GS on agricultural land for, e.g., precision farming purposes. [ABSTRACT FROM AUTHOR]

This paper presents the results of a systematic investigation of the natural radioactivity in rock samples of Davanagere locality, Karnataka, India. The radioactivity in rocks was measured using the NaI(TI) gamma-ray spectrometer. An effort was made to identify the minerals present in rock samples by FTIR spectroscopy. The activity of 232Th, 226Ra and 40K radionuclides in rocks vary from 27.96 ± 1.00 to 103.85 ± 1.90, 50.89 ± 1.98 to 135.28 ± 3.15 and 512.46 ± 4.86 to 974.31 ± 7.05 Bq kg−1with a mean value of 59.79 ± 1.45, 85.79 ± 2.54 and 787.03 ± 6.19 Bq kg−1, respectively. Radiological hazard parameters such as radium equivalent activity, external and internal hazard indices absorbed dose rate, ELCR for indoor exposure and annual effective doses for different body organs were estimated. The activity of natural radionuclides were found to be high compared to the national and world average values. However, the hazard indices were found to be within the recommended limits. The Quartz, Calcite and Kaolinite extinction coefficients in rocks ranged from 87.37 to 121.73, 31.43 to 119.14, and 33.10 to 63.97, respectively. The radionuclide activity concentration was found to depend on the kaolinite and calcite minerals. [ABSTRACT FROM AUTHOR]

Here is reported the synthesis of a magnetic phosphorus-containing adsorbent decorated with poly(N-isopropylacrylamide) (PNIPAM) brushes via surface-initiated atom transfer radical polymerization (SI-ATRP) and its application for vortex assisted solid phase extraction of lead in water, cigarettes and soil. The adsorbent was characterized using Fourier-transform infrared spectroscopy (FT-IR) and energy dispersive x-ray (EDX) spectroscopy. A high-resolution continuum source flame atomic absorption spectrometer (HR-CS FAAS) was used for the quantification of lead. All factors affecting the extraction efficiency including the solution pH, adsorbent dose, sample volume, vortex time, and elution protocols were optimized. The limits of detection (LOD) and quantification (LOQ) were determined to be 0.05 µg L−1 and 0.18 µg L−1, respectively. The preconcentration and enhancement factors were 20 and 18. Validation was performed using TMDA 64.3 fortified water and INCT-OBTL-5 tobacco leaves certified reference materials with satisfactory recoveries. The method was shown to be sensitive, efficient and reproducible. [ABSTRACT FROM AUTHOR]

The recent expansion of single particle inductively coupled plasma mass spectrometry (spICP-MS) for analysis of inorganic nanoparticles (NPs) in environmental and laboratory samples requires continued method development to ensure accurate characterization. Spectral interferences in spICP-MS analysis are often not fully addressed, especially particle generated interferences. Discrete ion clouds from ablated NPs entering the plasma form doubly charged and polyatomic species in a manner similar to dissolved ions that contribute to the continuous background signal. spICP-MS analysis of Y- and Nd-NP suspensions resulted in NP detections that are falsely identified as Pd, Ge, and As NPs due to interferences of YO+ and Nd2+. Use of a dynamic reaction cell (DRC) eliminated YO+ interferences, while Pd NPs were still accurately measured in mixed suspensions of Pd- and Y-NPs. A strong correlation was observed between the magnitude of interferences in solution mode and single particle mode, supporting a similar mechanism of interferent formation in the plasma for dissolved and NP-associated ions. Additionally, interference formation was affected by changes in nebulizer gas flow in a manner similar to dissolved ions. We conclude that particle generated interferences must be avoided or eliminated to ensure accurate nanometrology. [ABSTRACT FROM AUTHOR]

Thermal ionization mass spectrometry (TIMS) is a specialized technique that precisely measures isotopic ratios. This paper proposes the direct quantification of 90Sr at femtogram per litter (fg L−1) levels using isotope dilution (ID)-TIMS of preconcentrated samples. Although preconcentration is ineffective when measuring isotope ratios in classical TIMS, the magnification afforded by preconcentration improves the limit of detection (LOD) of 90Sr in ID-TIMS. After fixing the isotope ratio between stable Sr isotopes and 90Sr, the fg L−1-level 90Sr concentration was successfully obtained by the ID method (recovery R% = 100 ± 11.1%). The obtained LODs are improved by 105 times from those of conventional radiometric analysis such as oxalic acid precipitation/low background gas flow counters, which depend on the amount of coexisting natural Sr. Under the optimized conditions, the LOD was 9.03 attograms per liter (ag L−1), equivalent to a radioactivity concentration of 46.1 micro becquerels per liter (μBq L−1). The sample volume (10 mL containing 10 μg L−1 of natural Sr) roughly corresponds to a rainwater-level sample with 104-fold preconcentration. Spike and recovery tests were conducted on rain water and related environmental waters (stagnant stock water collected from a swimming pool immediately after the Fukushima Daiichi Nuclear Power Plant accident). The 90Sr levels were successfully quantified by the proposed method. [ABSTRACT FROM AUTHOR]