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Objective. Develop a prototype on-line positron emission tomography (PET) scanner and evaluate its capability of on-line imaging and intra-fractionated proton-induced radioactivity range measurement. Approach. Each detector consists of 32 × 32 array of 2 × 2 × 30 mm3 Lutetium–Yttrium Oxyorthosilicate scintillators with single-scintillator-end readout through a 20 × 20 array of 3 × 3 mm2 Silicon Photomultipliers. The PET can be configurated with a full-ring of 20 detectors for conventional PET imaging or a partial-ring of 18 detectors for on-line imaging and range measurement. All detector-level readout and processing electronics are attached to the backside of the system gantry and their output signals are transferred to a field-programable-gate-array based system electronics and data acquisition that can be placed 2 m away from the gantry. The PET imaging performance and radioactivity range measurement capability were evaluated by both the offline study that placed a radioactive source with known intensity and distribution within a phantom and the online study that irradiated a phantom with proton beams under different radiation and imaging conditions. Main results. The PET has 32 cm diameter and 6.5 cm axial length field-of-view (FOV), ∼2.3–5.0 mm spatial resolution within FOV, 3% sensitivity at the FOV center, 18%–30% energy resolution, and ∼9 ns coincidence time resolution. The offline study shows the PET can determine the shift of distal falloff edge position of a known radioactivity distribution with the accuracy of 0.3 ± 0.3 mm even without attenuation and scatter corrections, and online study shows the PET can measure the shift of proton-induced positron radioactive range with the accuracy of 0.6 ± 0.3 mm from the data acquired with a short-acquisition (60 s) and low-dose (5 MU) proton radiation to a human head phantom. Significance. This study demonstrated the capability of intra-fractionated PET imaging and radioactivity range measurement and will enable the investigation on the feasibility of intra-fractionated, range-shift compensated adaptive proton therapy. [ABSTRACT FROM AUTHOR]

Natural radioactivity measurement, radiation monitoring of the region, dose assessment and interpretation of radiological-related parameters are crucial aspects from the public awareness and environmental safety point of view. The ionising radiations (gamma-rays) emitted from radionuclides such as 226Ra, 232Th and 40K present in environmental materials contributes significantly to the external radiation dose received by the public. High-efficiency gamma spectrometry based on a 4″ × 4″ NaI (Tl) detector was employed for estimating activity concentrations of the gamma-emitting radioelements. The spectra from the detector were recorded using a PC-based 1k multichannel analyser system (WinTMCA 32). Each sample spectrum was acquired for a counting period of 60 000 s (16.67 hr). Assuming the daughter products of 226Ra and 232Th in equilibrium, the activity concentration of these radionuclides were estimated by using the prominent gamma photo peaks of daughter products. Using the same technique, dose-related radiological parameters were calculated for all the samples. The activity concentrations of the radionuclides and the dose-related parameters for the samples were found to be comparable with the global literature values. The data generated from our study will contribute to the baseline radiological data of the region. [ABSTRACT FROM AUTHOR]

Alpha flux radiated from 222Rn, 220Rn and progeny is the primary contributor of natural radioactivity to the inhabitants in the ambient atmosphere. The annual indoor 222Rn and 220Rn concentrations were found to be 85 ± 43 and 84 ± 36 Bq m−3, respectively. The estimated annual indoor 222Rn and 220Rn concentration is below to reference value of 100 Bq m−3 suggested by WHO. The calculated annual inhalation dose due to exposure to the alpha flux of 222Rn, 220Rn and their progeny is well below the recommended reference level given by UNSCEAR and ICRP. The data were further checked for normalisation and found that 222Rn and Effective Equilibrium Radon Concentration (EERC) data are not normally distributed. [ABSTRACT FROM AUTHOR]

Radiation dosimetry is an important task for assessing the biological damages created in human being due to ionising radiation exposure. Ionising radiation being invisible and beyond the perception of human natural sensors, the dosimetry equipments/systems are the utmost requirement for its measurement. Retrospective measurement of radiation doses is a challenging task as conventional radiation dosemeters are not available at the exposure site. The material/s in close proximity of exposed individual or individuals' biological samples may be used as retrospective radiation sensor for dosimetry purpose. Environment materials such as sand, bricks, ceramics, sand stones, quartz, feldspar, glasses and electronic chips have been utilised using TL (Thermoluminescence) techniques for retrospective gamma dose (min 10 cGy) measurement. Electron Spin Resonance techniques have been employed to human biological samples such as tooth enamel, bones, nails, hair, etc. and reported for dosimetry for ~20 cGy min dose measurement. Some commercial glasses have been found sensitive enough to measure the minimum gamma doses of the order of 100 cGy using TL techniques. For internal retrospective dosimetry, the radioactivity contamination assessment in food items, water, other edible product and ambient air are the prerequisites. The radioactivity concentration vis-à-vis their consumption rate may help in controlling the internal contamination and estimation of dose absorption in human body. Defence Laboratory, Jodhpur has been working extensively on the dosimetry techniques for external dose measurement using environmental material and developed portable contamination monitoring systems for food and water radioactivity measurement in the range of 50 Bq kg−1 to 1000 kBq kg−1 in 60 s measurement time. The recent research and development in the methodologies, equipments and systems undertaken towards capacity building and self-reliance in retrospective radiation dosimetry is reported in this paper. [ABSTRACT FROM AUTHOR]

This study represents the findings of the measurement of natural radioactivity in soil and water samples collected from the upper Himalayas region along the Manali–Leh Highway. The activity concentration values of terrestrial radionuclides in soil samples are measured using an n-type HPGe detector. The radiological hazards are also estimated through the evaluation of radium equivalent activity (Req), external and internal hazard index (Hex, Hin), alpha index (Iα), gamma index (Iγ), air absorbed dose, and indoor and outdoor effective dose. The level of Uranium in surface and ground water samples collected from the region is determined using the LED Fluorimetry technique. Annual effective dose, radiological and chemical toxicity risk, and hazards quotient due to the presence of uranium in water samples are also calculated. The values of these parameters are compared with permissible limits. [ABSTRACT FROM AUTHOR]

The Dismantling and Decommissioning (D&D) of nuclear facilities poses several challenges for radioactivity measurement laboratories involved in environmental radiation monitoring plans. One of them is the definition of the detection limits to be achieved for the radionuclides analysis in different samples. The detection limits should be set in such a way that the obtained concentration values for each radionuclide are easily discriminated from certain maximum activity concentration levels. These maximum activity concentration levels are usually set in view of the respective dose contributions from each radionuclide. There are some national legislations that settle detection limits for drinking water. However, there is no regulation containing detection limits for groundwater or surface water. In this way, different institutions or companies require very different detection limits for radioactivity concentration assessment in those types of water associated with D&D activities. In this work, we focus on the detection limits required for the D&D activities in rainwater, surface water and groundwater. We propose detection limits obtained by applying the WHO methodology for maximum activity concentration levels and compare with those requested by radioactive waste management agencies and regulatory bodies. Some real cases where our proposal allows identification of events are analysed and conclusions are extracted. [ABSTRACT FROM AUTHOR]

In this study, data from the first measurement of 236U in surface soil samples in Cameroon are reported, with the primary objective of establishing baseline data in the case of the accidental release of nuclear fuel to the environment in the future. For the first time in Cameroon, atom ratios of 236U/238U were determined, which ranged from 2.31 × 10− 8 to 4.95 × 10− 8. Furthermore, secular equilibrium between 238U and 226Ra in the sampled soils was studied, activity ratios of 226Ra/238U were out of unity. The 137 C activity concentrations occur as traces, ranging from below 0.1 to 6.7 Bq kg− 1. [ABSTRACT FROM AUTHOR]

Human beings are constantly exposed to the radiations coming from the environment. This work assesses the radiological hazards of natural radioactivity in soil samples taken at four locations around the phosphate area in south Tunisia. Concentrations of primordial radionuclides were measured by gamma spectrometer using an HPGe detector. The overall mean values of 40K, 226Ra and 232Th concentrations were 264, 27 and 13 Bq kg−1, respectively. From the radioactivity measurements, radiation hazard indices specified by the United Nation Scientific Committee on the Effect of Atomic Radiation such as radium equivalent activity (Raeq), absorbed dose rates (⁠|$ {\dot{\text D}} $|⁠) and annual effective dose (AED) to the population for outdoor environment were determined. The mean values for the abovementioned parameters were 64 Bq kg−1, 33 nGy h−1 and 40 μSv y−1, respectively. [ABSTRACT FROM AUTHOR]

Background: Glass 90Y microspheres are produced with known radionuclide impurities. These impurities are not independently monitored. Clinical instruments, including ionization chamber dose calibrators and positron emmission tomography (PET) cameras, can be much more sensitive in detecting signals from these impurities than to signals from 90Y itself. Purpose: The "typical" levels of 90Y impurities have been studied to assess their impact on dosimetry during internal implantation, and for the management of waste. However, unaccounted‐for decay spectra of impurities can also have an impact on dose calibrator and PET readings. Thus, even what might be considered negligibly small impurity fractions, can in principle cause substantial overestimates of the amount of 90Y activity present in a sample. To our knowledge, quantitative effects of radionuclide impurities in glass microspheres on activity measurements have not been documented in the field. As activity quantitation for dosimetry and its correlations with outcome becomes more prevalent, the effects of impurities on measurements may remain unaccounted for in dosimetry studies. Methods: In this letter, we review theoretical and physical considerations that will result in asymmetric errors in quantitation from 90Y impurities and estimate their typical and potential impact on clinical utilization. Among the common impurities 88Y is of particular concern for its impact on 90Y dose measurements because of its decay characteristics, along with other isotopes 91Y and 46Sc which can also impact measurements. Results: The typical level of 88Y impurities reported by the manufacturer should only cause small errors in dose calibrator and PET measurements made within the 12‐day label‐specified use‐by period, up to 2.0% and 1.6%, respectively. However, the product specification max allowable impurity levels, specified by the manufacturer, leave open the potential for much greater bias from within the 12‐day use‐by period, potentially as high as 13.2% for dose calibrator measurements and 10.6% for PET from the 88Y impurities. Conclusions: While typical levels of impurities appear to have acceptable impact on patient absorbed dose, it should be noted that they can have adverse effects on 90Y radioactivity measurements. Furthermore, there is currently minimal independent verification and/or monitoring of impurity levels within the field. [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]

Naturally occurring radioactivity was evaluated in the reservoir rock, surface soil samples, and oil production waste at the East Baghdad South (EBS) Oil Field. The radioactivity of uranium-238 (and radium-226), thorium-232, and potassium-40 were calculated in core samples from four geological formations: Al-Zubair, Al-Khasib, Tanuma, and Hartha Formations, which represent the oil reservoirs in the study area in addition to the natural GR and SGR logs for the oil well in EBS were calculated. The radioactivity of the above-mentioned nuclides was also measured for surface soil samples and waste samples from the site of the oil production industry at the EBS oilfield. The measurements included all the stages of oil production from the collection of crude oil from the wells stage to the storage of the manufactured oil. It also included measurements of radioactivity in samples for some sites outside the industry and near the oil wells in the region. Total radioactivity was measured in count/second and the exposure dose rates were also measured at all the above sites. Relatively high concentrations of uranium-238 and radium-226 were found in rock core samples of some geological units within the oil reservoir formations which will certainly move with the oil to the surface and collect with waste (such as sludge) when oil is produced. Although, some sites have higher Ra-226, Th-232, and K-40, in the sludge samples and oily soil, such as in the 1st separator stage, water separation (Desalter) stage, and near the waste pit, these locations are acceptable if they are compared with other oilfields worldwide. The gamma absorbed doses calculated inside the EBS oil industry were higher than the global average of (59) nGy/h where Ra-226 is the main contributor in these doses, on the other hand, external hazard index (Hex) values less than unity so they are acceptable according to UNSCEAR. Radiation dose values in some places in the study area exceed the values recommended by ICRP, UNSCEAR, and IAEA (1 mSv/y) for the public but less than the values recommended for workers (20 mSv/y). generally, the site of EBS- oilfield does not show radioactive contamination or significant radioactive hazards, as it is a new facility, and safety instructions are still strictly applied, and the removal of waste immediately before its spread by the activity of the workers in the facility. [ABSTRACT FROM AUTHOR]

To address the technical limitations of automatic coal and gangue detection technology in fully mechanized top coal caving mining operations, the low radiation level radioactivity measurement method is utilized to assess the degree of coal-gangue mixture in top coal caving process. This approach is based on the distinguishing radiation characteristics of natural γ-rays between coal and gangue. This study analyzed the distribution characteristics of natural γ-rays in coal and rock layers of thick coal seams and the applicability of this method, introduced the basic principle of coal-gangue detection technology based on natural γ-ray, developed the test system about automatic coal-gangue detection, studied the radiation characteristics of coal and gangue, proposed determination model of the coal-gangue mixed degree, combined with the time sequence characteristics of the top coal's releasing flow and the energy spectrum characteristics of different layers of rock, realized the precise coal-gangue detection technology in complex structure thick coal seam with multiple gangue. Field tests were conducted in Lilou, Xiaoyu and Tashan Coal Mine. The test results were well corroborated with the research results and achieved the expected results, which laid the foundation for the field application of intelligent coal mining. [ABSTRACT FROM AUTHOR]

The uncertainty of in situ radioactivity measurements can be influenced by the depth of sediment sampled by the spectrometer and the vertical distribution of the target radionuclide in the sediments. This study used Particle and Heavy Ion Transport Simulation code (PHITS) to evaluate the effective detection depth of a plastic scintillation fiber system (PSF) for monitoring radiocesium (RCs) in bottom sediments of agricultural ponds in Fukushima and thereafter, used 2015-2019 field measurement data from 47 ponds to evaluate the depth dependence of PSF calibration factors and its influence on measurement uncertainty. Though no significant differences were observed in PSF-derived RCs concentrations by calibration depth, PSF calibration factors and normalized mean square error (NMSE) suggest a potential dependence on the depth of sediment containing 90% of RCs inventory (L90) such that it may be the optimal choice for calibrating PSF. Accordingly, revision of PSF calibration depth from the currently adopted top 10 cm to the top 15-20 cm may be necessary for optimizing PSF measurement uncertainty not only because their calibration factors had the best coefficients of determination and yielded lowest NMSE, but also because they constituted the largest proportion of L90 among the 206 samples. [ABSTRACT FROM AUTHOR]

Plastic scintillation microsphere (PSm) is a micron-sized plastic scintillator, and it is an organic scintillation material with good application prospects in the field of radioactivity analysis. However, the lack of simple industrial synthesis methods could limit bulk production of PSm with a reasonable cost. In this study, PSm materials were prepared via suspension polymerization and the repeatability of both the synthesis conditions and the radioactivity measurement performance were evaluated. Results indicated that PSm with a particle size distribution ranged around 90–200 μm can be reproducibly synthesized under certain conditions. Consistent counting efficiency for the 14C measurement in liquid samples using PSm has been obtained as long as sufficient PSm was added into the scintillation vial to completely cover the liquid volume. By comparing the spectral widths of samples with different concentrations of fluors, optimal PPO concentration of 1.5% and bis-MSB concentration of 0.015% was chosen to obtain a good light yield and a counting efficiency of up to 43.3% for 14C in water. Furthermore, it was observed that the 14C counting efficiency of PSm would be significantly affected by the quenching of the solution. [ABSTRACT FROM AUTHOR]

This work presents the first in-depth study of soil radioactivity in the mangrove forest of Bangladesh part of the Sundarbans. It used HPGe gamma-ray spectrometry to measure the amount of natural radioactivity in soil samples from Karamjal and Harbaria sites of the world's largest mangrove forest. The activity concentrations of most of the 226Ra (14±2 Bqkg-1 to 35±4 Bqkg-1) and 232Th (30±5 Bqkg-1 to 50±9 Bqkg-1) lie within the world average values, but the 40K concentration (370± 44 Bqkg-1 to 660±72 Bqkg-1) was found to have exceeded the world average value. The evaluation of radiological hazard parameters revealed that the outdoor absorbed dose rate (maximum 73.25 nGyh-1) and outdoor annual effective dose (maximum 0.09 mSvy-1) for most samples exceeded the corresponding world average values. The elevated concentration of 40K is mainly due to the salinity intrusion, usage of fertilizers and agricultural runoff, and migration of waste effluents along the riverbanks. Being the pioneering comprehensive research on the Bangladesh side of the Sundarbans, this study forms a baseline radioactivity for the Sundarbans before the commissioning of the Rooppur Nuclear Power Plant in Bangladesh. [ABSTRACT FROM AUTHOR]

We measured the terrestrial activity contents, radiation doses; hazard indices and excessive lifetime cancer risk (ELCR) from primordial radionuclides (226Ra, 232Th and 40K) in 50 soil samples collected from the five selected hospitals within Imo State, Nigeria. Radioactivity measurements were carried out by the method of gamma-ray spectrometry with thallium doped sodium iodide [NaI(Tl)] detector. The mean activity values obtained for the radionuclides 226Ra, 232Th and 40K (respectively) in Federal Medical Centre, Owerri (FMC); General Hospital, Umuguma, Owerri West, (GHW); Neuroscience Hospital, Ohaji Egbema (NHO); St. Joseph Hospital, Okigwe (SJH); Imo State University Teaching Hospital, Orlu (IMSUTH) are: 20.56±4.73, 14.96±3.42 and 105.65±31.40 Bqkg-1; 11.77±3.03, 17.45±4.20 and 63.67±18.44 Bqkg-1; 17.97±4.65,10.02±2.18 and 190.43±42.83 Bqkg-1; 11.36±3.71, 17.39±4.46 and 76.29±25.08 Bqkg-1; and 11.84±3.64, 4.89±2.25 and 165.18±58.41 Bqkg-1 respectively. These values were below the worldwide average values: 32 Bqkg-1 for 226Ra, 45 Bqkg-1 for 232Th, and 412 Bqkg-1 for 40K as documented by UNSCEAR (2000). 40K recorded the highest mean activity compared to 226Ra and 232Th in the studied soil samples. Radium equivalent activity (Raeq), absorbed gamma dose rate (Dr), annual effective dose equivalent (AEDE), external hazard index (Hex), gamma representative index (Ιϒr) and annual gonadal dose equivalent (AGDE), were calculated to quantify the radiation risk to the public from exposure to 226Ra, 232Th and 40K in the studied samples. In addition, excess lifetime cancer risk (ELCR) was also accessed. The mean computed values of the excess lifetime cancer risk for FMC, GHW, NHO, SJH and IMSUTH are 0.08±0.03, 0.09±0.15, 0.10±0.2, 0.10±0.03 and 0.07±0.02 respectively. The mean values of these hazard parameters were within the acceptable safety limits provided for human safety and environmental protection. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To reduce the ore loss and dilution caused by blast-induced rock movement in open-pit bench blasting, a dividing open-pit blast (DOPB) method was theoretically analyzed, numerically simulated and applied to the Husab Uranium Mine, Namibia. First, a general open-pit bench blasting process was analyzed, and the DOPB method was introduced after comparing it with the echelon pattern. Next, the blasting processes of the echelon pattern and the DOPB method were simulated using the boned-particle method, while the finite element method was used to provide a blast loading. Finally, two field applications of the DOPB method to reduce ore loss and dilution in Husab Uranium Mine were introduced in detail, and the trial blast results were verified by 3D scanning results, radioactivity measurement results and ore recovery datasets. The obtained results show that multi-hole bench blasting can be considered to be the combination of multiple independent single-hole blasting when the delay time is large enough. Meanwhile, the DOPB method can be used to reduce the mixing of ore and waste rock fragments, and an identifiable ditch that matches the ore boundary can be created in the muckpile. Therefore, serious ore loss and dilution can be avoided even using the pre-blast ore boundary to guide shovel loading. In addition, a more complex identifiable ditch can be formed with the help of more accurate electronic detonators. [ABSTRACT FROM AUTHOR]

Another example is IAEA CRPs, where the IAEA brings together scientists from all over the world to collaborate on focused research topics of shared interest, important to the agency's mission. 5 IAEA Research Reactor database, https://nucleus.iaea.org/rrdb 6 International Atomic Energy Agency, I Compact Accelerator based Neutron Sources i , TECDOC-1981 (2021). The International Atomic Energy Agency (IAEA) is the world center for cooperation in the nuclear field to help accelerate and enlarge the safe, secure, and peaceful use of nuclear technologies. IAEA Nuclear Science and Instrumentation Laboratory - Training Remit NSIL is one of the eight nuclear application laboratories the IAEA operates in Seibersdorf, 40 km south of Vienna. [Extracted from the article]

Periodic maintenance of stack aviation lamps was taken up in the Compact Reprocessing of Advanced Fuels in Lead Cells reprocessing plant in Kalpakkam. The entire ventilation system of the plant had to be shut down during this maintenance work. When the ventilation system is switched off, natural radioactivity will build up in the working environment. The increased magnitude of the natural radioactivity concentration was estimated by counting the air samples (AS) at predetermined intervals to ensure no long-lived radionuclide (LLR) was present in the AS. The extent of the natural radioactivity rose to a factor of 100, and no LLR was present in the collected AS. In addition, the collected AS and data analysis of the same revealed that there was no breach of containment during the work. [ABSTRACT FROM AUTHOR]

Measurements of natural radioactivity in drinking water have been evaluated in most parts of the world to assess the dose rate and irradiation risk. This work aims to determine the natural radioactivity of bottled drinking water produced in Dire Dawa City and the surrounding area. Natural radioactivity water from nine different brandsis produced and commonly sold in bottles. The measurement was done by gamma-ray spectroscopy using a hyper-pure germanium detector. The water specific activity in 238U ranged from 2.91 ± 0.42 to 4.04 ± 0.42 Bq L-1; in 226Th, it ranged from 4.66 ±2.48 to 13.31 ± 0.2.48 Bq L-1, and in 40K, it ranged from 106. 52 ± 8.71 to 136.52 ± 8.71 Bq L-1. These results were compared with the reported values from other countries. Annual estimated effective doses from the intake of natural radionuclides in bottled drinking water were found to be below the limit of 0.1 mSv y-1 recommended by World Health Organization (WHO). The cumulative average annual effective doses of 238U for different age groups of (0 - 1), (1 - 2), (2 - 7), (7 - 12), (12 - 17) years, and above 17 years were estimated to be 3.01, 0.30, 0.60, 0.90, 2.88, and 0.66 mSv y-1, respectively. [ABSTRACT FROM AUTHOR]

The natural radioactivity of 238U, 232Th, and 40K was measured in selected samples from 11 monitoring stations along the Euphrates River in Elanbar governorate in 2022, using a NaI (Tl) gamma-ray spectroscopy detector 3" in diameter. The results showed that the average activity concentrations of 238U (214Bi), 232Th (208Tl), and 40K in the water samples were 4.29, 1.62, and 10.95 Bq/L, respectively. Cations and heavy metals were measured using flame and flame atomic absorption spectroscopy (FAAS). The concentrations of Pb2+, Na+, and K+ were 0.02, 207, and 22 mg/L, respectively. According to the information provided by the World Health Organization, the samples studied in this work revealed the correlation between the heavy metals and cations. On the whole, waters of Elanbar governorate are unsafe in terms of the concentration of natural radioactive and heavy metals. [ABSTRACT FROM AUTHOR]

Total radioactivity measurements (cps) in 59 sites were achieved in the Hit–Kubaiysa–Haditha area. Geological samples (soil and rock) from those sites were analyzed for Ra-226, U-238, Th-232, and K-40 using Gamma spectroscopy system based on high pure germanium. The study aims to assess the radioactivity in the study area and attempt to understand the relationship between radioactivity and the geological situation in the area. The results showed that many sites have relatively high total radioactivity exceeding the background radioactivity by many times. The radioactivity concentrated in areas around the springs spreading in the area caused by the high concentration of Ra-226 which being have disequilibrium with its parent U-238. Some areas also have a relatively high concentration of U-238 in depressions areas where the upper part of the Euphrates Formation is outcropped. Based on the pattern of the spread of total radioactivity in the study area, the extension of the Euphrates Fault Zone and the Abu Jir Fault Zone could be determined. These fault zones extend towards northwest–southeast, in addition to the delineation of some of the recent faults that intersect with these zones in an east–west direction, most of which follow the spreading pattern of the springs in the region. [ABSTRACT FROM AUTHOR]

In the article "Estimation of Cosmic-Ray-Induced Atmospheric Ionization and Radiation at Commercial Aviation Flight Altitudes", the main source of the ionization of the Earth's atmosphere, i.e., the cosmic radiation that depends on solar activity as well as geomagnetic activity, was investigated. This Special Issue, "Advances in Environmental Applied Physics", is dedicated to collecting original papers from eminent researchers in the field of environmental pollutants, which constitute a health risk to the population, increasing the likelihood of incurring cancer. The assessment was performed by using high-purity germanium (HPGe) gamma ray spectrometry, with the aim of quantifying the specific activity of the SP 234m sp Pa radioisotope after a preconcentration procedure, and thus to assess the activity concentration of SP 238 sp U, in a hypothesis of the secular radioactive equilibrium between it and its daughter. Moreover, many ongoing studies for predicting the production rates of cosmogenic nuclides, forecasting changes in atmospheric compositions and climate, assessing the cosmic radiation exposure of aircraft crew and the effects on precise electronic devices, use numerical models that estimate cosmic radiation intensities in the atmosphere. [Extracted from the article]

The aim of this study is to determine the natural radioactivity levels and evaluate the radiological hazard in vegetable samples collected from Kirkuk city by using gamma-ray spectrometer HPGe. The results show that the highest specific activity of 226Ra and 232Th in vegetables was (9.65, 7.9) Bq.kg–1 in Vg27 (Root/Garlic) while, the highest specific activity of 40K was (221.08 Bq.kg–1 in Vg37 (Leguminous/kidney bean), respectively. The results show that the average specific activities in vegetable samples for 226Ra and 232Th, and 40K was (6.119, 4.763 and 135.595) Bq.kg–1, respectively, these results were found to be below natural radiation exposure reported by UNSCEAR, radium equivalent activity (Raeq) were varied from maximum value (30.345 Bq.kg–1 in Vg15 (Leafy/coriander leaves)) to minimum value 13.002 Bq.kg–1 in Vg37 (Leguminous/kidney bean)) with average value 23.371 Bq.kg–1, the total average annual effective dose in vegetable samples for adults, children (10 years old) and infants are estimated to be (60.487, 128.090 and 170.431 μSvy–1), respectively, than those below the WHO permissible limit of 0.3 m μSvy–1. The calculated values of external and internal hazard index in the samples which were lower than the worldwide average value 1, respectively; therefore, these values are found to be safe. The level of radioactivity concentrations in vegetables was determined to ensure consumer safety and the results provide useful information to assess the dose emitted from this radioactivity due to ingestion of these vegetables. This study is very important to investigate the level of radioactivity of vegetables and the findings of this study will useful to determine a baseline of radioactivity exposure to the human from ingestion of vegetables. [ABSTRACT FROM AUTHOR]

In this study suitability of α-ZrP nanoparticles as a 223Ra and 225Ac carriers for TAT was investigated. The yields of radiolabelling were higher than 98% in both cases. Subsequently, in vitro stability studies were carried out in various biological matrices during 48 h period. Measurements of released radioactivity showed the highest stability in saline. Released activity of 223Ra, 225Ac and their daughter radionuclides was around 0.5%. On the other hand, the lowest stability was shown in plasma and serum. Released activity for 223Ra, 225Ac and their progeny atoms was from 15 to 32%. [ABSTRACT FROM AUTHOR]

Measurement of 238U, 233Th and 40K concentrations in soil samples collected from Ziggurat of Dur-Kurigalzu west region of Baghdad, have been evaluated, using high purity germanium detector. The activity concentrations of 238U, 233Th and 40K varied from 16.040  to 26.620, 14.510  to 31.480, and 153.820  to 266.320  with average values of 20.604±2.9, 24.534±3.3, 212.22±25.1, respectively. The importance of these measurements lies in the estimation of radiation risk, radium equivalent, absorbed dose, annual effective dose, risk indices, gamma index, and cancer risk. The average value of the absorbed dose ranged from 33.187  outdoors to 63.111  indoors. The mean annual effective dose value was estimated to be 0.043  outdoors and 0.310  indoors from the study area. The total calculated lifetime risk of cancer ranged from 0.991×10-3 to 1.485×10-3, while the indoor lifetime cancer risk exceeded the recommended limit in samples 6, 8, 9, and 10.  The areas examined in this study showed radioactive contamination less than the internationally permissible limits for the sites inhabited by the population. [ABSTRACT FROM AUTHOR]

The underwater gamma-ray spectrometer KATERINA was calibrated in a special tank and then demonstrated in the Southern Caspian Sea to determine the radioactivity levels in seawater as well as in the sediment. The simulated marine efficiency of the in situ detection system was validated analyzing the high energetic (1764 keV of 214Bi and 2614 keV of 208Tl) gamma-ray peaks using their known activity concentration as determined from the low energy emissions. The analysis of the in situ gamma-ray spectra in a short acquisition time period provided quantitative data for 226Ra and 232Th progenies as well as for 40K. A satisfactory analysis was performed for quantifying the observed energy peaks in the seawater and sediment measurements acquired at the south coast of the Caspian Sea. The spectrum in the water tank was also analyzed using full spectrum analysis methods, and the reproduced spectrum was in a very good agreement with the experimental spectrum giving as an output the activity concentrations of the observed radionuclides. [ABSTRACT FROM AUTHOR]

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The present work of this study involves an advanced analytical procedure that allows direct and fast determining the specific activity of 238U and 235U using the gamma-rays of 63.3 keV and 185.7 keV after subtraction of the contribution of overlapping peaks. This procedure also included MCNP-CP code in order to calculate the coincidence summing and the self-absorption correction factor. Validation of the developed procedure was confirmed by the IAEA proficiency test to calculate the activities of radionuclides in various types of samples such as rich thorium, secular equilibrium, and disequilibrium of uranium. The final scores were received "acceptable" for all radionuclides. [ABSTRACT FROM AUTHOR]

In this study, the results of environmental radioactivity studies conducted in Köprübaşı, Manisa district, where Türkiye's uranium mineral exploration and processing studies were carried out, are shared. Because this is a populated area, there is a need for radio ecological dosimetry assessment to investigate the possible risk to the population. The region where radiological monitoring is carried out is discussed in two parts as the areas where uranium mineral exploration is performed and the settlements close to these areas. It was observed that 714–4714 nGy/h values were obtained in the outdoor absorbed dose rate in air measurements taken in the areas where mineral exploration was performed and this value reached up to 22 857 nGy/h in open field mining areas. In the residential areas, it was recorded that the outdoor absorbed dose rate in air values ranged between 142 and 242 nGy/h and the indoor values ranged between 171 and 400 nGy/h. The world absorbed dose rate in air average values is 57 nGy/h (outdoor) and 75 nGy/h (indoor). The high 226Ra values in the radioactivity analyses of the soil samples draw attention. The mean values of the activity concentrations of the radionuclides 226Ra, 232Th and 40K in the soil samples are 3169, 55 and 802 Bq/kg and the world averages of these values are 35, 30 and 400 Bq/kg, respectively. It was determined that high 226Ra value in the soil in the areas close to the open field uranium mining area was passed on to the agricultural products. Radioactivity measurement results of drinking water samples did not exceed World Health Organization guidelines. According to the radon gas measurement results of 44 houses in Köprübaşı villages, the average radon concentrations in winter, spring, summer and autumn seasons were 72, 61, 50 and 55 Bq/m3, and the annual average value was 60 Bq/m3, respectively. Although these values are greater than the world average of 46 Bq/m3, they are below the recommended limit value (100 Bq/m3). By evaluating the data obtained, the total annual effective equivalent dose values (originating from outdoor–indoor absorbed dose in air, drinking water and indoor radon gas concentration) to which the people in the region are exposed were calculated as a 3.12 mSv. [ABSTRACT FROM AUTHOR]

Rural and isolated communities traditionally lack adequate water treatment and distribution systems, and water quality assessment often does not include radioactivity measurement. Here we present, for the first time, the results of Rn measurements and the evaluation of the associated dose in groundwaters of rural communities in a semiarid area in Paraiba State, Brazil. Water samples were analysed using a low-level liquid scintillation spectrometer (LSS). Radon concentrations were higher than EPA and WHO recommended levels in water for most of the wells (range of 5.5–1107.0 Bq/L, average 252.8 Bq/L). Higher Rn concentration was measured in deeper wells and located in area rich in granite and diorite rocks. The annual effective doses varied between 0.021 and 4.317 mSv/y for infants, 0.016–3.182 mSv/y for children, and 0.015–3.022 mSv/y for adults, exceeding, in some cases, the 1 mSv/y reference level recommended by the WHO and UNSCEAR for the public. Thus, water consumption from half of the wells should be avoided unless adequate treatment is provided. Results highlight the need to perform actions to supply water with appropriate quality to the local population. [ABSTRACT FROM AUTHOR]

In nuclear facilities, the mandatory atmosphere surveillance is operated by Continuous Air Monitors. This standalone instrument is designed to measure the airborne aerosol activity concentration and to trig an alarm signal when a predetermined activity concentration is exceeded. However, a rapid resuspension event of coarse aerosol leads to a measurement error: the airborne aerosol activity concentration is over-evaluated. Prior results have shown that the coarse aerosol deposit disturbs the background evaluation for the radioactivity measurement. The interactions between radioactive aerosols (with radon daughters) and coarse non-radioactive aerosols have to be investigated by running together aerosol models and nuclear simulations. Therefore, this paper investigates different ways to represent an aerosol deposit in numerical simulations. We developed two numerical aerosol deposit models that we integrated into Geant4, a tool for the simulation of the passage of radiations through matter, and then compared these to experimental results. The simplest model was discarded, and by using the second model, we managed to correctly frame our simulation results as an experimental measurement: an aerosol has been correctly considered in a nuclear simulation. By combining theory, simulations, and experimentations on both aerosol science and nuclear physics, this research will be able to improve the comprehension of monitors' behaviour in delicate situations and, more broadly, the filtration of aerosols using radioactivity. [ABSTRACT FROM AUTHOR]

There has been scientific debate about speculations that 'neutrino-induced' radioactive decay causes apparent violations of the exponential-decay law. Sturrock and others repeatedly publish papers asserting influences by solar and cosmic neutrinos on radioactive decay measurements and therefrom draw conclusions about space science that are highly speculative. Recurrent themes in their work are claims that the solar neutrino flux reveals oscillations at a monthly rate which can be linked to solar rotation, that annual and monthly oscillations occur in radioactive decay rates or directionality of emitted radiation which can be linked to variations in solar and cosmic neutrino flux hitting Earth's surface, and that unstable radioactivity measurements can be used as a source of information about the interior of the Sun and dark matter. Radionuclide metrologists have extensively investigated and refuted their arguments. Metrological evidence shows that radioactive decay does not violate the exponential-decay law and is not a probe for variations in solar neutrino flux. In this review paper, the main arguments of Sturrock are listed and counterarguments are presented. Reference is made to earlier published work in which the evidence has been scrutinised in detail. [ABSTRACT FROM AUTHOR]

Radionuclides, whether naturally occurring or artificially produced, are readily detected through their particle and photon emissions following nuclear decay. Radioanalytical techniques use the radiation as a looking glass into the composition of materials, thus providing valuable information to various scientific disciplines. Absolute quantification of the measurand often relies on accurate knowledge of nuclear decay data and detector calibrations traceable to the SI units. Behind the scenes of the radioanalytical world, there is a small community of radionuclide metrologists who provide the vital tools to convert detection rates into activity values. They perform highly accurate primary standardisations of activity to establish the SI-derived unit becquerel for the most relevant radionuclides, and demonstrate international equivalence of their standards through key comparisons. The trustworthiness of their metrological work crucially depends on painstaking scrutiny of their methods and the elaboration of comprehensive uncertainty budgets. Through meticulous methodology, rigorous data analysis, performance of reference measurements, technological innovation, education and training, and organisation of proficiency tests, they help the user community to achieve confidence in measurements for policy support, science, and trade. The author dedicates the George Hevesy Medal Award 2020 to the current and previous generations of radionuclide metrologists who have devoted their professional lives to this noble endeavour. [ABSTRACT FROM AUTHOR]

There are many and varied working conditions very important for the researcher. In this work, two of these conditions and their change effects on the radioactive measurement were studied, time and temperature. Seven powder samples of the most commonly spices which used in the Iraqi kitchens were collected from different markets. The radioactive spectrum of each sample is taken by using NaI(Tl) detector have crystal of (3×3) inch, then the specific activity were calculated with two times, 3 hrs. and 24 hrs. and compared with their effect on the samples. The results shows that the specific activity values of the three nuclides 40K, 214Bi and 208Tl decrease with the increasing of measurement time. This result leads to whenever the time of measurement is higher the specific activity is lower, therefore, the measurement at 24 is more suitable for all radioactivity measurements for low radioactive materials like spices. With respect to the temperature change, the measurements, hence specific activity were estimated in Summer and Winter seasons. The results show that all the specific activity values of the nuclide 40K increase with the decreasing of measurement temperature, while It is the opposite behavior for the nuclides 214Bi and 208Tl. All these increasing and decreasing behavior are very slight, therefore, the changing of temperature or weather of measurement for low radioactive materials has no significant effects on the results. [ABSTRACT FROM AUTHOR]

This paper sketched the basic principles of ceramic materials radioactivity measurement and mathematical calculation formula of testing time. When the sample measurement conditions and the way of data analysis are constant, using sodium iodide gamma spectrometer for getting the radioactive spectra data of 5 groups of samples. In condition of the background count time tb or sample measurement time ts increasing gradually, study the radioactivity specific activity measurement error range of all samples. It is derived when the background count rate of nb and sample counting rate ns is constant, the measurement error ν2 and the sum of reciprocal of the background count time tb and reciprocal of the sample measuring time ts for approximately linear positive correlation. The measurement error of 226Ra, 232Th, 40K radioactive specific activity of different ceramic samples presents the corresponding fluctuations as their initial energy spectrum count rate differences. This study for coordination of the contradiction between ceramic materials radioactive measurement time and the uncertainty has certainly theoretical and practical value. [ABSTRACT FROM AUTHOR]

To compare the measurement results of a portable survey meter with a soil-based dose rate assessment method, the gamma absorbed dose rates in the air were measured at 27 sites. The soil-based gamma absorbed dose rates in the air were calculated using established conversion factors and the activity concentrations of 226Ra, 232Th and 40K of the soil at the sites. The gamma absorbed dose rate averages of the portable survey meter, and computing from the activity concentrations in the soil were 65.8 ± 4.26 and 64.8 ± 3.68 nGy⋅h−1, respectively. A significant positive correlation was found in the comparison between the evaluated gamma absorbed dose rates from soil radioactivity and in the air. Conversion factors based on the local soils converting to the absorbed dose rate were computed from the portable survey meter data and the soil activity concentrations, and it was compared with others. [ABSTRACT FROM AUTHOR]

In situ radioactivity measurements were performed to describe and map the relationship between the radioactive concentration distribution on the surface and geological formations in the Karadeniz Technical University (KTU) campus and surrounding area located on the shore of the Black Sea in NE Turkey. The concentrations of radio-elements (eU, eTh, and K) and dose rate values were measured using a portable gamma-ray spectrometer with NaI(Tl) crystal at 150 points in the study area with a duration of 5 min for each measurement point. In addition, the geochemical radio-element ratios (eTh/eU, K/eU, and eU/eTh) give information about the origin of the rocks, and radiological hazard parameters for humans and the environment were also calculated. Average values of eU, eTh, and K concentrations, and dose rate, were calculated to be 3.59 ppm, 13.46 ppm, 0.84%, and 65.38 nGy/h, respectively. While the highest concentrations of radio-element and dose rate values were recorded at outcrops of Eocene-Neogene basaltic rocks and red clays, which are the weathering product of the Kabaköy formation, the lower anomaly zones coincide with brown and reddish brown forest and agricultural soils of volcanic origin in the study area. According to the average radio-element ratios, it was concluded that the rocks in the study area do not completely originate from the crust, but formed as a result of the mixture of upper mantle and continental crust. All the calculated hazard parameters seem to be lower than the internationally recommended values, and there is no cancer risk in and around the campus area. [ABSTRACT FROM AUTHOR]

A dual-plane Compton imaging detector previously developed for prompt gamma imaging has been further tested and calibrated for quantitative radioactivity determination, specifically to assess radioactive debris from a reactor fuel element. The debris piece contains uranium isotopes and several long-lived fission products, including cesium-137 (Cs-137). The detector consists of two pixelated planes of cadmium-zinc-telluride (CZT) crystals which record gamma ray events interacting within these volumes. In addition to the energy spectrum obtained by pulse height analysis, the time-stamped events from each detector pixel are sorted by location into 3 categories for post-processing: intra-plane, inter-plane, and coincidence. An image reconstruction software enables spatial localization of the select gamma ray peak(s) from the spectrum, thereby separating the gamma ray by specific isotopes. We used the camera to image a small piece of debris for demonstration purposes. A measurement was performed alongside a high purity germanium (HPGe) detector, which could determine the isotopes' absolute activities and be used as a reference for the camera. In addition, a known isotopic point source was used to calibrate the camera’s energy detection efficiency in the same measurement geometry, correlating the image pixel intensity to the isotopic activity. [ABSTRACT FROM AUTHOR]

A new system for the implementation of the 4πβ (plastic scintillator)–4πγ coincidence counting technique was developed and tested by measuring the activity of a 60Co solution. This system captures energy and time stamps in the form of binary list mode data to implement an offline-analysis method (OAM) through Python scripts. This technique enables us to easily refine and modify the analysis parameters without having to constantly gather new data. The OAM allows us to address various challenges such as dead time and accidental coincidences. It also incorporates corrections for background and decay. To determine the activity of a source, the β efficiency was varied using computerized discrimination methods and extrapolated to an efficiency of 100%. The results of our study demonstrated excellent agreement with the reference value. This study contributes valuable insights into radionuclide measurement techniques, offering a robust system for precise absolute radioactivity measurements. [ABSTRACT FROM AUTHOR]

Neutron activated concrete reference material for measurement of residual radioactivity by gamma-ray spectrometry has been prepared. The main radionuclides were 60Co, 152Eu, 54Mn, 154Eu and 134Cs. One-way ANOVA homogeneity test has shown that the samples are homogeneous. The activity concentrations of 54Mn, 59Fe, 154Eu and 134Cs were relatively low; only 60Co activity concentration was found to be higher therefor it was considered as the main target isotope. The prepared sample can be used as a tool to prove compliance to radiation protection and environmental regulations during decommissioning of cyclotron buildings or other irradiation facilities that produce residual radioactivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unique triple scintillator setup providing active background shielding, resulting in reduced background counts and improved accuracy in dose rate measurements. • Pulse classification algorithms boosted by UMAP/HDBSCAN* machine learning, enabling precise discrimination between different types of radiation particles and enhancing the system's sensitivity. • Incorporation of an active Rn-222 and Rn-220 removal system, effectively eliminating overcounting and allowing for increased sample mass, particularly beneficial for low radioactivity samples and rapid measurements. The μDOSE+ is a novel measurement system designed for environmental radioactivity measurements and trapped charge dating applications. This study describes improvements integrated into the μDOSE+ system. These enhancements include a redesigned counting chamber equipped with an active radon removal system, passive shielding and an active shielding module that is further refined by machine learning algorithms for precise pulse classification. These advancements collectively lead to a significant reduction in background in the β counting window, improved α and β counting efficiency and easier sample handling. This is demonstrated through a comparative analysis with its predecessor, the classical μDOSE system. [ABSTRACT FROM AUTHOR]

Kütahya is one of the provinces with many well-known spas in Turkey. Radionuclide levels in the thermal waters of these spas have not been measured before. Therefore, the radon and radium concentrations in thermal waters collected from Kütahya spas were measured using the collector chamber method. In addition, the indoor radon concentrations of spas were determined using LR-115 type II solid-state nuclear track detectors. The annual effective doses from the inhalation and ingestion of radon and radium concentrations have been calculated. The sampling points' physical and chemical properties were also measured during the survey. [ABSTRACT FROM AUTHOR]

The published literature offers only a few records of direct measurement of the natural radioactivity in nephrite. The present study used high-purity germanium (HPGe) low-background gamma-ray spectrometry to measure activity concentrations of primordial radionuclides in 11 serpentinite-related nephrite (ortho-nephrite) samples from deposits in Poland, Russia, Canada, and New Zealand, along with three samples of rodingite and serpentinite from a nephrite deposit in Nasławice, Poland. All nephrite samples exhibited very low 40K, 232Th, and 238U activity concentrations that fell within the range of published values for ultrabasic and basic rocks. The nephrite samples from Jordanów (Poland) gave the highest uranium and thorium activity concentration values. Two samples of plagiogranitic rodingite showed significantly higher 238U and 232Th activity concentrations than the values measured for nephrite. Nephrite thorium and uranium concentrations correlated strongly (r = 0.98), and the corresponding Th/U ratios appear unique according to geographical location. The mean estimated potassium, thorium, and uranium concentrations from ortho-nephrite analyzed here were compared with corresponding mean values previously reported for dolomite-related nephrite (para-nephrite). The comparison indicates that the ortho-nephrites studied have similar uranium concentrations but lower mean potassium concentrations and higher mean thorium concentrations than those reported for para-nephrite in the literature. [ABSTRACT FROM AUTHOR]

Objective: Ex vivo radioactivity measurement of positron emission tomography/computed tomography (PET/CT)-guided biopsy tissue specimen to check the viable tumor sampling and predict the nature of the biopsied lesion. Materials and Methods: We prospectively evaluated the retrieved tissue specimens during PET/CT-guided biopsies for the presence of radioactivity. The qualitative radioactivity was measured by acquiring PET/CT images of the specimen. For quantitative analysis, a multichannel-analyzer (MCA) was used, and a counting-factor (CF) in counts/mCi.mm³ was calculated based on background-corrected net-counts, tissue-volume (mm³), and exponential tracer-activity during biopsy (mCi). The CF-values were compared with the 2-(fluorine-18) fluoro-2-deoxy-D-glucose-avidity in the target lesion and correlated with the histopathology. Results: A total of 49 patients (30 males) aged 51.8 ± 17.8 years were recruited for the biopsy, and radioactivity was measured. All the specimens revealed the presence of radioactivity on PET/ CT images of the specimens and MCA counting. The mean CF-values were 17.2 ± 15.6 counts/mCi. mm³. One sample had meager counts with a CF-value of 0.162 and was subjected to re-biopsy after repositioning the coaxial needle to the hypermetabolic site. Pathological diagnosis was established in all the patients (malignancy-29, benign-20). The CF-values were significantly higher in malignant lesions than benign (21.45 ± 18.05 vs. 10.76 ± 8.96 counts/mCi.mm³, P = 0.025). CF-values and maximum standardized uptake value had a significant correlation (Pearson's r = 0.457, P = 0.001). Conclusion: The ex vivo measurement of the radioactivity of retrieved tissue specimens during PET/CT-guided biopsy helps to confirm the sampling from viable region and a highly practical approach to avoid erroneous sampling of a lesion with a large necrotic area. It is also helpful in predicting the nature of the biopsied lesion before the histopathological analysis. [ABSTRACT FROM AUTHOR]