This study systematically investigates natural radioactivity in groundwater from the densely populated eastern Gonghe Basin in Qinghai Province,aiming to reveal its spatial distribution,origins,and potential health ri...This study systematically investigates natural radioactivity in groundwater from the densely populated eastern Gonghe Basin in Qinghai Province,aiming to reveal its spatial distribution,origins,and potential health risks.The characteristics of gross-αand gross-βactivities,as well as the concentrations of nuclide including^(238)U,^(232)Th,and^(226)Ra,have been investigated in groundwater samples from 12 groups encompassing various types such as hot springs and artesian wells across different aquifer systems.Correlation analysis and dose estimation models were applied to preliminary estimate the radiation exposure to local residents and to explore the genesis and hazards of natural radioactivity in groundwater.Results indicate that overall groundwater radioactivity in the Gonghe Basin remains within acceptable limits,with mean gross-αand gross-βactivity concentrations of 0.32 Bq/L and 0.27 Bq/L,respectively.Approximately 83.33%of samples comply with relevant national standards.However,two fault-controlled high-temperature spring samples exhibited gross-αactivity exceeding regulatory limits,with one also showing elevated gross-βactivity surpassing China's Class III groundwater quality standards for radioactivity.Furthermore,single-radionuclideαradioactivity from^(230)Th,^(226)Ra,^(210)Po,and^(232)Th exceeded regulatory thresholds in some samples,suggesting potential long-term health risks.While most samples complied with effective dose limits,four showed^(210)Poαradioactivity exceedances within controllable risk ranges.The findings suggest that groundwater radioactivity in the region is primarily controlled by geological structures,lithology,and hydrothermal conditions,with fault zones and high-temperature environments serving as key factors in radionuclide enrichment.This research provides scientific foundation for the sustainable development of geothermal resources and the prevention of radioactive water contamination.Continuous monitoring of high-radioactivity hot springs and prudent resource utilization are recommended.展开更多
The potential of high-intensity lasers to influence nuclear decay processes has attracted considerable interest.This study quantitatively evaluated the effects of high-intensity lasers on α decay and cluster radioact...The potential of high-intensity lasers to influence nuclear decay processes has attracted considerable interest.This study quantitatively evaluated the effects of high-intensity lasers on α decay and cluster radioactivity.Our calculations revealed that,among the parent nuclei investigated,^(144)Nd is the most susceptible to laser-induced alterations,primarily because of its relatively low decay energy.Additionally,circularly polarized lasers exhibit a greater impact on decay modifications than linearly polarized lasers.Given the limited time resolution of current detectors,it is essential to account for the timeaveraging effect of the laser.By incorporating the effects of circular polarization,time averaging,and angular averaging,our theoretical predictions indicated that the modification of^(144)Nd decay could reach 0.1%at an intensity of 10^(27)W/cm^(2).However,this intensity significantly exceeds the current laser capability of 10^(23)W/cm^(2),and the predicted modification of 0.1%remains below the detection threshold of contemporary measurement techniques.Observing laser-assistedαdecay and^(14)C cluster radioactivity will likely remain unfeasible until both ultrahigh laser intensities and significant advancements in experimental resolution are achieved.展开更多
In the current study,we examined every possible cluster-daughter combination in the heavy-particle decay of isotopes ^(297-300)119 and computed the decay half-lives using the modified generalized liquid drop model(MGL...In the current study,we examined every possible cluster-daughter combination in the heavy-particle decay of isotopes ^(297-300)119 and computed the decay half-lives using the modified generalized liquid drop model(MGLDM)with the preformation factor depending on the disintegration energy.The predicted half-life of every heavy cluster(Z_(C)≥32)was within the experimentally observable limits.These results aligned with the predictions of Poenaru et al.[Phys.Rev.Lett.107,062503(2011)]that superheavy nuclei(SHN)with Z>110 will release heavy particles with a penetrability comparable to or greater than theα-decay.The half-lives predicted using the MGLDM for clusters^(89)Rb,^(91)Rb,and^(92)Rb from parents^(297)119,^(299)119,and^(300)119,respectively,agreed with the predictions of Poenaru et al.[Eur.Phys.J.A 54,14(2018)].It was found that the isotopes of heavy clusters Kr,Rb,Sr,Pa,In,and Cd had half-lives comparable to theαhalf-life;and isotopes of clusters I,Xe,and Cs had the minimum half-life(10^(-14)s).These observations revealed the role of the shell closure(Z=82,N=82,and N=126)of the cluster and daughter nuclei in heavy-cluster radioactivity.We predicted that isotope ^(297,299)119 decayed by 4αdecay chains and isotope^(300)119 decayed by 6αdecay chains,while^(298)119 decayed by continuousαdecay chains.The predicted half-lives and modes of decay of the nuclei in the decay chains of^(297-300)119 agreed with the experimental data,proving the reliability of our calculations.The present study determined the most favorable heavy-cluster emissions from these nuclei and provided suitable projectile-target combinations for their synthesis.展开更多
The effective liquid drop model(ELDM)is improved by introducing an accurate nuclear charge radius formula and an analytic expression for assaulting frequency.Within the improved effective liquid drop model(IMELDM),the...The effective liquid drop model(ELDM)is improved by introducing an accurate nuclear charge radius formula and an analytic expression for assaulting frequency.Within the improved effective liquid drop model(IMELDM),the experimental cluster radioactivity half-lives of the trans-lead region are calculated.It is shown that the accuracy of the IMELDM is improved compared with that of the ELDM.At last,the cluster radioactivity half-lives that are experimentally unavailable for the trans-lead nuclei are predicted by the IMELDM.These predictions may be useful for searching for new candidates for cluster radioactivity in future experiments.展开更多
During the last few decades,rare isotope beam facilities have provided unique data for studying the properties of nuclides located far from the beta-stability line.Such nuclei are often accompanied by exotic structure...During the last few decades,rare isotope beam facilities have provided unique data for studying the properties of nuclides located far from the beta-stability line.Such nuclei are often accompanied by exotic structures and radioactive modes,which represent the forefront of nuclear research.Among them,two-proton(2p)radioactivity is a rare decay mode found in a few highly proton-rich isotopes.The 2p decay lifetimes and properties of emitted protons hold invaluable information regarding the nuclear structures in the presence of a low-lying proton continuum;as such,they have attracted considerable research attention.In this review,we present some of the recent experimental and theoretical progress regarding the 2p decay,including technical innovations for measuring nucleon-nucleon correlations and developments in the models that connect their structural aspects with their decay properties.This impressive progress should play a significant role in elucidating the mechanism of these exotic decays,probing the corresponding components inside nuclei,and providing deep insights into the open quantum nature of dripline systems.展开更多
In this study,we systematically investigated the two-proton(2p)radioactivity half-lives from the excited state of nuclei near the proton drip line within the Gamowlike model(GLM)and modified Gamow-like model(MGLM).The...In this study,we systematically investigated the two-proton(2p)radioactivity half-lives from the excited state of nuclei near the proton drip line within the Gamowlike model(GLM)and modified Gamow-like model(MGLM).The calculated results were highly consistent with the theoretical values obtained using the unified fission model[Chin.Phys.C 45,124105(2021)],effective liquid drop model,and generalized liquid drop model[Acta Phys.Sin 71,062301(2022)].Furthermore,utilizing the GLM and MGLM,we predicted the 2p radioactivity halflives from the excited state for some nuclei that are not yet available experimentally.Simultaneously,by analyzing the calculated results from these theoretical models,it was found that the half-lives are strongly dependent on Qand l.展开更多
The radioactivity concentrations of 226Ra, 232Th and 40K in 24 samples of natural and manufactured building materials commonly used in Bangladesh were measured using HPGe gamma ray spectrometer. The results in the pre...The radioactivity concentrations of 226Ra, 232Th and 40K in 24 samples of natural and manufactured building materials commonly used in Bangladesh were measured using HPGe gamma ray spectrometer. The results in the present study were compared with the world average and also with the reported data available in literature. The radium equivalent activity, the absorbed dose rate, annual effective dose, external and internal hazard indices, gamma index, alpha index, annual gonadal dose equivalent and excess lifetime cancer risk were also evaluated to assess the potential radiation hazards associated with these building materials. All samples under investigation were found to be within the recommended safety limit and do not pose any significant radiation hazards. This study can be used as a reference for more extensive studies of the same subject in future.展开更多
To search for new candidates of the true and simultaneous two-proton(2 p)radioactivity,the 2 p decay energies(Q2 p)are extracted by the Weizs?cker–Skyrme-4(WS4)model,the finite-range droplet model(FRDM),the Koura–Ta...To search for new candidates of the true and simultaneous two-proton(2 p)radioactivity,the 2 p decay energies(Q2 p)are extracted by the Weizs?cker–Skyrme-4(WS4)model,the finite-range droplet model(FRDM),the Koura–Tachibana–Uno–Yamada(KTUY)model and the Hartree–Fock–Bogoliubov mean-field model with the BSk29 Skyrme interaction(HFB29).Then,the 2 p radioactivity half-lives are calculated within the generalized liquid drop model by inputting the four types of Q2 pvalues.By the energy and half-life constraints,it is found that the probable 2 p decay candidates are the nuclei beyond the proton-drip line in the region of Z≤50 based on the WS4 and KTUY mass models.For the FRDM mass model,the probable 2 p decay candidates are found in the region of Z≤44.However,the 2p-decaying candidates are predicted in the region of Z≤58 by the HFB29 mass model.It means that the probable 2 p decay candidates of Z>50 are only predicted by the HFB29 mass model.Finally,the competition between the true 2p radioactivity andα-decay for the nuclei above the N=Z=50 shell closures is discussed.It is shown that~(101)Te,~(111)Ba and~(114)Ce prefer to 2p radioactivity and the dominant decay mode of~(107)Xe and~(116)Ce isα-decay.展开更多
In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nucl...In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nuclear potential to be a modified Woods–Saxon potential that contains the isospin effect of the daughter nucleus. It was found that the calculated half-lives could reproduce the experimental data well. Furthermore, we extended this model to predict the half-lives of 17 protonemitting candidates whose radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, the unified fission model, Coulomb potential and proximity potential model, universal decay law for proton emission, and new Geiger–Nuttall law were also used. All the predicted results are consistent with each other.展开更多
In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.De...In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.Demonstration reveals that the theoretical results acquired by CPPM exhibit a high level of consistency with prior theoretical models such as the unified fission model(UFM),generalized liquid-drop model(GLDM)and effective liquid-drop model(ELDM).Furthermore,within the CPPM,we predicted the half-lives of potential 2p radioactive nuclei for which experimental data are currently unavailable.The predicted results were then assessed,compared with UFM,ELDM and GLDM models,and examined in detail.展开更多
Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured...Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured in marine sand deposits from Liaodong Bay (LDB), North Yellow Sea (NYS), Zhoushan area (ZS), Taiwan Shoal (TS) and Pearl River Mouth (PR), offshore China, which are potential marine sand mining areas. The radiation activity equivalent (Raeq), indoor gamma absorbed dose rate (DR), annual effective dose (HR), alpha index (Ia), gamma index (Ig), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the marine sands offshore China. From the analysis, it is found that these marine sands are safe for the constructions. The Pearson correlation coefficient reveals that the 226Ra distribution in the marine sands offshore China is controlled by the variation of the 40K concentration. Principal component analysis (PCA) yields a two-component representation of the entire data from the marine sands, wherein 98.22% of the total variance is explained. Our results provide good baseline data to expand the database of radioactivity of building materials in China and all over the world.展开更多
The immobilized photosynthetic bacterium, Rhodobacter shpaeroides SSI (SSI), cultured on porous 2 cm ceramic beads, effectively removed and recovered 20 mg/L of non-radioactive Cs (almost 100%) and Sr (≌50%), after 3...The immobilized photosynthetic bacterium, Rhodobacter shpaeroides SSI (SSI), cultured on porous 2 cm ceramic beads, effectively removed and recovered 20 mg/L of non-radioactive Cs (almost 100%) and Sr (≌50%), after 3 - 5 days of aerobic treatment. Toxic and heavy metals such as Hg, Cr, Pb and As were also removed, almost 100%, after 6days of aerobic treatment. A practical method of removal of radioactivity of 10 - 30 μSv/h, caused mainly by radioactive Cs released from the accident at the Daiichi Nuclear Power Plant on 11th March 2011, from sediment mud and soil in Fukushima, Japan, was also carried out. Using immobilized SSI beads, more than 90% and 42% - 73% of radioactive Cs was removed and recovered from sediment mud and soil, respectively, after 3 - 14 days of aerobic treatment in an outdoor 60 L vessel. The weight and mass of the harvested beads could be reduced by more than 97% after desiccation. This technology of removal and recovery had therefore, considerable advantages over other technologies that demanded very large storage facilities in Fukushima. After removal of radioactivity from polluted soil, vegetables like Komatsuna (Turrip leaves) and Chingensai (Green pakchoi) were cultivated on remediated soil. Safe vegetables grown on these treated soils showed a radioactivity content lower than the recommended limit for edible foods in Japan, i.e. less than <100 Bq/kg. Treatment by SSI beads, therefore, appeared to be a compact and suitable technology that could make significant contributions towards agricultural recovery in radioactively polluted areas of Fukushima.展开更多
A study on the detection of probable radionuclides and their activity concentrations in the raw material (phosphate rock), final product (fertilizer) and waste samples collected from all the phosphate fertilizer facto...A study on the detection of probable radionuclides and their activity concentrations in the raw material (phosphate rock), final product (fertilizer) and waste samples collected from all the phosphate fertilizer factories (total two factories—A Diammonium Phosphate, DAP and a Triple Super Phosphate, TSP factory) in Bangladesh were carried out. A total of seven types of samples (grossly divided into solid and liquid types);liquid waste, waste-mixed river water, normal river water, phosphate rock, phosphate fertilizer, solid waste and normal soil;were analyzed under this study. Raw material samples were collected only from the TSP fertilizer factory. Fertilizer, solid and liquid waste samples were collected from both the factories under study. Moreover, normal soil and natural surface water samples from the suitable areas adjacent to the factories were also collected for the comparison purpose. The samples were analyzed by gamma ray spectrometry technique using a Hyper-Pure Germanium (HPGe) detector of 40% relative efficiency. The analysis of the samples showed that only natural radionuclides such as 226Ra, 232Th and 40K were present in the samples and no traces of artificial radioactivity were found in any of the samples. 40K was found below the detection limit in some samples. The analysis of the samples in the case of TSP fertilizer factory showed that the average activity concentrations of 226Ra and 232Th and 40K in raw materials were 851.27 ± 7.10, 19.63 ± 6.57 and 54.06 ± 5.93 Bq/kg, respectively, in final product 211.90 ± 4.74, 42.48 ± 10.56 Bq/kg and ND (Not Detected), respectively, in solid waste 187.49 ± 4.88, 70.06 ± 11.76 and 289.27 ± 40.24 Bq/kg, respectively and in liquid waste 6.26 ± 0.63, 10.01 ± 1.39 Bq/L and ND, respectively. The measured results in the case of samples collected from DAP fertilizer factory showed that the average activity concentrations of 226Ra and 232Th and 40K in the final product were 17.31 ± 3.92, 69.74 ± 9.88 and 48.46 ± 17.22 Bq/kg, respectively, in solid waste 24.47 ± 4.15, 164.62 ± 11.08, 191.52 ± 33.74 Bq/kg, respectively and in liquid waste 3.59 ± 1.05, 37.08 ± 3.30 Bq/L and ND, respectively. Considering the stored raw materials and wastes the part of the ambient environment of the factory, radium equivalent activity, radiation hazard index and external annual effective dose to the workers and public due to these materials were also calculated and compared with world average values.展开更多
Nine medicinal or herbal plants used in Iraq were analyzed to determine natural radioactivity. The radionuclides were determined by Gross alpha, beta and gamma spectrometry Proportional counter + NaI(Tl) detector type...Nine medicinal or herbal plants used in Iraq were analyzed to determine natural radioactivity. The radionuclides were determined by Gross alpha, beta and gamma spectrometry Proportional counter + NaI(Tl) detector type(XLB5) and gamma-ray spectroscopy with (HPGe) techniques. The activity concentration of 40K ranged from 124.1 Bq/kg in (Crust sample) to 88.3 Bq/kg in (Chamomile sample), for gross alpha ranged from (N.D.) in (Flax sample) to 0.4 cpm in (Anise sample), while for beta ranged from 5.7 cpm in (Flax sample) to 25.6 cpm in (Latency sample) and for gamma ranged from 0.6 cpm in (Thyme sample) to 5.10 cpm in (Coriander and Flax samples).展开更多
Radioactivity measurements were carried out around Maumba and Nguluku villages, two of the proposed sites for titanium mining in the coastal area of Kenya. Samples of surface soils were analyzed using a HPGe gamma spe...Radioactivity measurements were carried out around Maumba and Nguluku villages, two of the proposed sites for titanium mining in the coastal area of Kenya. Samples of surface soils were analyzed using a HPGe gamma spectrometer. The average activity concentrations for 226Ra, 232Th and 40K are 20.9 ±7.6, 27.6 ± 9.1 and 69.5 ± 16.5 Bqkg–1, respectively. The absorbed dose rates in air, calculated on the basis of the measured activity concentrations, range from 9.8 to 50.0 nGyh-1, with an average of 29.2 nGyh-1. These values are below the global population-weighted mean, and they should be considered when planning appropriate monitoring and surveillance programmes during the mining operation, as well as the reclamation and restoration programmes after mining.展开更多
The activity concentrations of naturally occurring 238U, 232Th and 40K in surface soils along Qarun Lake and Wadi El Rayan located in Faiyum, Egypt were determined. The measurements were carried out through gamma-ray ...The activity concentrations of naturally occurring 238U, 232Th and 40K in surface soils along Qarun Lake and Wadi El Rayan located in Faiyum, Egypt were determined. The measurements were carried out through gamma-ray spectrometry using a coaxial HPGe detector. The results were compared with those reported in the literature. The radiological hazard radium-equivalent activity index, external and internal indices, radioactivity level index, absorbed dose rate, annual effective dose rate and total absorbed dose rate associated with radioactivity in all samples were evaluated and compared with recommended values. Correlation studies between pairs of radionuclides were performed and discussed.展开更多
As the traditional methods can not meet the requirements of marine radioactivity monitoring,a radioactivity monitoring sensor used in marine field has been proposed.This sensor is based on Nal(TI) scintillation crysta...As the traditional methods can not meet the requirements of marine radioactivity monitoring,a radioactivity monitoring sensor used in marine field has been proposed.This sensor is based on Nal(TI) scintillation crystal and employs the special shielding method,the anticoincidence design,the spectrum stabilization algorithm of characteristic peaks and the Monte Carlo simulation fitting calibration formula.Through the continuous tests of terminals and the activity test for target nuclide ^(40)K,it is found that the sensor is stable and the error is less than 10%.展开更多
The aim of our present work is to measure the specific activities of the radionuclides 226Ra, 232Th, 40K and the exhalation rates in terms of area and mass of 222Rn in some samples of building materials commonly used ...The aim of our present work is to measure the specific activities of the radionuclides 226Ra, 232Th, 40K and the exhalation rates in terms of area and mass of 222Rn in some samples of building materials commonly used in Morocco in order to evaluate the radiological risk caused by natural radioactivity. To this end, the analyses were carried out, using two nuclear techniques, namely high resolution gamma spectrometry and alpha dosimetry based on the use of LR115, on 50 samples collected from large commercial suppliers in Morocco. The results of these analyses show that the average specific activities of 226Ra, 232Th and 40K in these materials vary from 9 to 52 Bq/kg, 3 to 63 Bq/kg and 68 to 705 Bq/kg respectively. These activities remain within the permissible limits of 35 Bq/kg, 30 Bq/kg and 370 Bq/kg respectively, with the exception of a few samples of red brick, gray cement, ceramic and granite. The activity of the radium equivalent (Raeq), the internal (Hin) and external (Hex) hazard indices, the absorbed dose rate, the total annual effective dose , the excess lifetime cancer risk (ELCR) as well as volumic activities, exhalation rates in terms of area (ES) and mass (EM) are calculated for the samples analyzed in this work in order to assess the radiological risks resulting from the use of these materials in various construction activities. It seems that the values of these indices vary from 19 to 196 Bq/kg, 0.08 to 0.67, 0.05 to 0.53, 9 to 91 nGy/h, 0.05 to 0.56 mSv/y, 0.19 × 10−3 to 1.96 × 10−3, 72 to 350 Bq/m3, 56 to 273 mBq⋅m−2⋅h−1 and 3 to 15 mBq⋅kg−1⋅h−1 respectively. The lowest values are identified for gypsum, while the highest are attributed to granite. All of the obtained results of these indices respect the permissible limits except for the Raeq in some granite samples, the ELCR index in all samples except gypsum and the radon volumic activity in some gray cement samples, ceramic and granite. As a result, the different types of building materials analyzed in our work do not present a health risk to the public and can be used in various construction activities, with the exception of a few samples of red brick, gray cement, ceramic and granite. The choice of the use of red brick, gray cement and ceramic should be monitored and adapted according to the criteria of the limitation of the doses whereas the use of the granite must be moderate in order to limit over time the health risk which increases with the duration of exposure of humans to these building materials.展开更多
The experimental detection of the hidden periodicities in the activity of various radioactive sources which were observed by different instruments and which coincided with the period of the free oscillations of the Su...The experimental detection of the hidden periodicities in the activity of various radioactive sources which were observed by different instruments and which coincided with the period of the free oscillations of the Sun gave an impetus to the further research. The simultaneous recording of gamma rays from two radioactive sources revealed the elements of synchronism and the periods of solar oscillations as well as the phase delay for the different sources in the obtained time series. A neutrino detector has been designed and tested, the advanced schemes for neutrino detection are developed, and the impact of the neutrino source on the radioactive matter is explored. The search for the new principles for creating the emitters of neutrino beams is conducted.展开更多
<p> The concentrations and distribution of naturally occurring radionuclides <span><span><span><span>(</span><sup><span>238</span></sup><span>U, </s...<p> The concentrations and distribution of naturally occurring radionuclides <span><span><span><span>(</span><sup><span>238</span></sup><span>U, </span><sup><span>235</span></sup><span>U, </span><sup><span>234</span></sup><span>U, </span><sup><span>230</span></sup><span>Th, </span><sup><span>226</span></sup><span>Ra, </span><sup><span>210</span></sup><span>Pb, </span><sup><span>232</span></sup><span>Th, </span><sup><span>228</span></sup><span>Ra, and </span><sup><span>40</span></sup><span>K)</span></span></span></span><span><span><span><span> were determined by alpha and gamma spectrometry in soil and sediments collected from Luilu and Dilala rivers located in the mining district of Kolwezi (Lualaba Province) of the Democratic Republic of the Congo. The average concentrations of </span><sup><span>238</span></sup><span>U and </span><sup><span>226</span></sup><span>Ra in the analyzed samples were 5</span></span></span></span><span><span><span> </span></span></span><span><span><span>-</span></span></span><span><span><span> </span></span></span><span><span><span>10 times higher than the world average values for soil provided by the </span></span></span><span><span><span>United Nations Scientific Committee on the Effects of Atomic Radiation. However,</span></span></span><span><span><span><span> the average concentrations of </span><sup><span>232</span></sup><span>Th were found similar to the world average. In both river basins, artisanal mining activities and</span></span></span></span><span><span><span> mineral washing sites displayed the higher concentration values of radionuclides. The mean values of health risk indices calculated for those sites were found sig</span></span></span><span><span><span>nificantly higher compared to world average levels. Radiation protection measures seem needed to ensure the radiation safety of local populations.</span></span></span> </p> <p> <span><span><span><br /> </span></span></span> </p> <p> <span style="font-size:16px;"><strong>Graphical Abstract</strong></span> </p> <p> <span><span><span><img src="Edit_7a1bf87c-f0a0-4c34-80b2-7e488ac5e4a2.png" alt="" /><br /> </span></span></span> </p>展开更多
文摘This study systematically investigates natural radioactivity in groundwater from the densely populated eastern Gonghe Basin in Qinghai Province,aiming to reveal its spatial distribution,origins,and potential health risks.The characteristics of gross-αand gross-βactivities,as well as the concentrations of nuclide including^(238)U,^(232)Th,and^(226)Ra,have been investigated in groundwater samples from 12 groups encompassing various types such as hot springs and artesian wells across different aquifer systems.Correlation analysis and dose estimation models were applied to preliminary estimate the radiation exposure to local residents and to explore the genesis and hazards of natural radioactivity in groundwater.Results indicate that overall groundwater radioactivity in the Gonghe Basin remains within acceptable limits,with mean gross-αand gross-βactivity concentrations of 0.32 Bq/L and 0.27 Bq/L,respectively.Approximately 83.33%of samples comply with relevant national standards.However,two fault-controlled high-temperature spring samples exhibited gross-αactivity exceeding regulatory limits,with one also showing elevated gross-βactivity surpassing China's Class III groundwater quality standards for radioactivity.Furthermore,single-radionuclideαradioactivity from^(230)Th,^(226)Ra,^(210)Po,and^(232)Th exceeded regulatory thresholds in some samples,suggesting potential long-term health risks.While most samples complied with effective dose limits,four showed^(210)Poαradioactivity exceedances within controllable risk ranges.The findings suggest that groundwater radioactivity in the region is primarily controlled by geological structures,lithology,and hydrothermal conditions,with fault zones and high-temperature environments serving as key factors in radionuclide enrichment.This research provides scientific foundation for the sustainable development of geothermal resources and the prevention of radioactive water contamination.Continuous monitoring of high-radioactivity hot springs and prudent resource utilization are recommended.
基金supported by the National Natural Science Foundation of China(Nos.12475136 and 12075327)。
文摘The potential of high-intensity lasers to influence nuclear decay processes has attracted considerable interest.This study quantitatively evaluated the effects of high-intensity lasers on α decay and cluster radioactivity.Our calculations revealed that,among the parent nuclei investigated,^(144)Nd is the most susceptible to laser-induced alterations,primarily because of its relatively low decay energy.Additionally,circularly polarized lasers exhibit a greater impact on decay modifications than linearly polarized lasers.Given the limited time resolution of current detectors,it is essential to account for the timeaveraging effect of the laser.By incorporating the effects of circular polarization,time averaging,and angular averaging,our theoretical predictions indicated that the modification of^(144)Nd decay could reach 0.1%at an intensity of 10^(27)W/cm^(2).However,this intensity significantly exceeds the current laser capability of 10^(23)W/cm^(2),and the predicted modification of 0.1%remains below the detection threshold of contemporary measurement techniques.Observing laser-assistedαdecay and^(14)C cluster radioactivity will likely remain unfeasible until both ultrahigh laser intensities and significant advancements in experimental resolution are achieved.
文摘In the current study,we examined every possible cluster-daughter combination in the heavy-particle decay of isotopes ^(297-300)119 and computed the decay half-lives using the modified generalized liquid drop model(MGLDM)with the preformation factor depending on the disintegration energy.The predicted half-life of every heavy cluster(Z_(C)≥32)was within the experimentally observable limits.These results aligned with the predictions of Poenaru et al.[Phys.Rev.Lett.107,062503(2011)]that superheavy nuclei(SHN)with Z>110 will release heavy particles with a penetrability comparable to or greater than theα-decay.The half-lives predicted using the MGLDM for clusters^(89)Rb,^(91)Rb,and^(92)Rb from parents^(297)119,^(299)119,and^(300)119,respectively,agreed with the predictions of Poenaru et al.[Eur.Phys.J.A 54,14(2018)].It was found that the isotopes of heavy clusters Kr,Rb,Sr,Pa,In,and Cd had half-lives comparable to theαhalf-life;and isotopes of clusters I,Xe,and Cs had the minimum half-life(10^(-14)s).These observations revealed the role of the shell closure(Z=82,N=82,and N=126)of the cluster and daughter nuclei in heavy-cluster radioactivity.We predicted that isotope ^(297,299)119 decayed by 4αdecay chains and isotope^(300)119 decayed by 6αdecay chains,while^(298)119 decayed by continuousαdecay chains.The predicted half-lives and modes of decay of the nuclei in the decay chains of^(297-300)119 agreed with the experimental data,proving the reliability of our calculations.The present study determined the most favorable heavy-cluster emissions from these nuclei and provided suitable projectile-target combinations for their synthesis.
基金supported by the National Natural Science Foundation of China(Grant Nos.U1832120 and 11675265)S&T Program of Hebei(Grant No.236Z4601G)+4 种基金Scientific Research Foundation for the Introducing Returned Overseas Chinese Scholars of Hebei Province(Grant No.C20230360)Natural Science Foundation for Outstanding Young Scholars of Hebei Province(Grant No.A2020210012)Natural Science Foundation of Hebei Province(Grant No.A2021210010)Key Laboratory of High Precision Nuclear Spectroscopy,Institute of Modern Physics,Chinese Academy of Sciences(Grant No.IMPKFKT2021002)Key Project of Natural Science Foundation for Basic Discipline Research of Hebei Province(Grant No.A2023210064)。
文摘The effective liquid drop model(ELDM)is improved by introducing an accurate nuclear charge radius formula and an analytic expression for assaulting frequency.Within the improved effective liquid drop model(IMELDM),the experimental cluster radioactivity half-lives of the trans-lead region are calculated.It is shown that the accuracy of the IMELDM is improved compared with that of the ELDM.At last,the cluster radioactivity half-lives that are experimentally unavailable for the trans-lead nuclei are predicted by the IMELDM.These predictions may be useful for searching for new candidates for cluster radioactivity in future experiments.
基金partially supported by the National Natural Science Foundation of China (Nos. 12147101, 11925502,11935001,11961141003, 11890714)the National Key R&D Program of China (No.2018YFA0404404)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDB34030000)the Shanghai Development Foundation for Science and Technology(No. 19ZR1403100)
文摘During the last few decades,rare isotope beam facilities have provided unique data for studying the properties of nuclides located far from the beta-stability line.Such nuclei are often accompanied by exotic structures and radioactive modes,which represent the forefront of nuclear research.Among them,two-proton(2p)radioactivity is a rare decay mode found in a few highly proton-rich isotopes.The 2p decay lifetimes and properties of emitted protons hold invaluable information regarding the nuclear structures in the presence of a low-lying proton continuum;as such,they have attracted considerable research attention.In this review,we present some of the recent experimental and theoretical progress regarding the 2p decay,including technical innovations for measuring nucleon-nucleon correlations and developments in the models that connect their structural aspects with their decay properties.This impressive progress should play a significant role in elucidating the mechanism of these exotic decays,probing the corresponding components inside nuclei,and providing deep insights into the open quantum nature of dripline systems.
基金supported by the National Natural Science Foundation of China(Nos.12175100 and 11975132)the Construct Program of the Key Discipline in Hunan Province+3 种基金the Research Foundation of the Education Bureau of Hunan Province,China(No.18A237)the Natural Science Foundation of Hunan Province,China(No.2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USCthe Opening Project of the Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(No.2019KFZ10)。
文摘In this study,we systematically investigated the two-proton(2p)radioactivity half-lives from the excited state of nuclei near the proton drip line within the Gamowlike model(GLM)and modified Gamow-like model(MGLM).The calculated results were highly consistent with the theoretical values obtained using the unified fission model[Chin.Phys.C 45,124105(2021)],effective liquid drop model,and generalized liquid drop model[Acta Phys.Sin 71,062301(2022)].Furthermore,utilizing the GLM and MGLM,we predicted the 2p radioactivity halflives from the excited state for some nuclei that are not yet available experimentally.Simultaneously,by analyzing the calculated results from these theoretical models,it was found that the half-lives are strongly dependent on Qand l.
文摘The radioactivity concentrations of 226Ra, 232Th and 40K in 24 samples of natural and manufactured building materials commonly used in Bangladesh were measured using HPGe gamma ray spectrometer. The results in the present study were compared with the world average and also with the reported data available in literature. The radium equivalent activity, the absorbed dose rate, annual effective dose, external and internal hazard indices, gamma index, alpha index, annual gonadal dose equivalent and excess lifetime cancer risk were also evaluated to assess the potential radiation hazards associated with these building materials. All samples under investigation were found to be within the recommended safety limit and do not pose any significant radiation hazards. This study can be used as a reference for more extensive studies of the same subject in future.
基金supported by the National Natural Science Foundation of China(Grants No.U1832120 and No.11675265)the Natural Science Foundation for Outstanding Young Scholars of Hebei Province of China(Grants No.A2020210012 and A2018210146)+1 种基金the Continuous Basic Scientific Research Project(Grant No.WDJC-2019-13)the Leading Innovation Project(Grant No.LC 192209000701)。
文摘To search for new candidates of the true and simultaneous two-proton(2 p)radioactivity,the 2 p decay energies(Q2 p)are extracted by the Weizs?cker–Skyrme-4(WS4)model,the finite-range droplet model(FRDM),the Koura–Tachibana–Uno–Yamada(KTUY)model and the Hartree–Fock–Bogoliubov mean-field model with the BSk29 Skyrme interaction(HFB29).Then,the 2 p radioactivity half-lives are calculated within the generalized liquid drop model by inputting the four types of Q2 pvalues.By the energy and half-life constraints,it is found that the probable 2 p decay candidates are the nuclei beyond the proton-drip line in the region of Z≤50 based on the WS4 and KTUY mass models.For the FRDM mass model,the probable 2 p decay candidates are found in the region of Z≤44.However,the 2p-decaying candidates are predicted in the region of Z≤58 by the HFB29 mass model.It means that the probable 2 p decay candidates of Z>50 are only predicted by the HFB29 mass model.Finally,the competition between the true 2p radioactivity andα-decay for the nuclei above the N=Z=50 shell closures is discussed.It is shown that~(101)Te,~(111)Ba and~(114)Ce prefer to 2p radioactivity and the dominant decay mode of~(107)Xe and~(116)Ce isα-decay.
基金supported in part by the National Natural Science Foundation of China(Nos. 12175100 and 11975132)the Construct Program of the Key Discipline in Hunan Province+4 种基金the Research Foundation of Education Bureau of Hunan Province,China(Nos. 21B0402 and 18A237)the Natural Science Foundation of Hunan Province, China(No. 2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USC, the Shandong Province Natural Science Foundation, China(No. ZR2022JQ04)the Hunan Provincial Innovation Foundation for Postgraduates(No.CX20220993)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(No. 2019KFZ10)。
文摘In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nuclear potential to be a modified Woods–Saxon potential that contains the isospin effect of the daughter nucleus. It was found that the calculated half-lives could reproduce the experimental data well. Furthermore, we extended this model to predict the half-lives of 17 protonemitting candidates whose radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, the unified fission model, Coulomb potential and proximity potential model, universal decay law for proton emission, and new Geiger–Nuttall law were also used. All the predicted results are consistent with each other.
基金supported by the National Natural Science Foundation of China(Nos.12175100 and 11975132)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of Education Bureau of Hunan Province,China(No.18A237)+1 种基金the Natural Science Foundation of Hunan Province,China(No.2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USC,the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(No.2019KFZ10).
文摘In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.Demonstration reveals that the theoretical results acquired by CPPM exhibit a high level of consistency with prior theoretical models such as the unified fission model(UFM),generalized liquid-drop model(GLDM)and effective liquid-drop model(ELDM).Furthermore,within the CPPM,we predicted the half-lives of potential 2p radioactive nuclei for which experimental data are currently unavailable.The predicted results were then assessed,compared with UFM,ELDM and GLDM models,and examined in detail.
文摘Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured in marine sand deposits from Liaodong Bay (LDB), North Yellow Sea (NYS), Zhoushan area (ZS), Taiwan Shoal (TS) and Pearl River Mouth (PR), offshore China, which are potential marine sand mining areas. The radiation activity equivalent (Raeq), indoor gamma absorbed dose rate (DR), annual effective dose (HR), alpha index (Ia), gamma index (Ig), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the marine sands offshore China. From the analysis, it is found that these marine sands are safe for the constructions. The Pearson correlation coefficient reveals that the 226Ra distribution in the marine sands offshore China is controlled by the variation of the 40K concentration. Principal component analysis (PCA) yields a two-component representation of the entire data from the marine sands, wherein 98.22% of the total variance is explained. Our results provide good baseline data to expand the database of radioactivity of building materials in China and all over the world.
文摘The immobilized photosynthetic bacterium, Rhodobacter shpaeroides SSI (SSI), cultured on porous 2 cm ceramic beads, effectively removed and recovered 20 mg/L of non-radioactive Cs (almost 100%) and Sr (≌50%), after 3 - 5 days of aerobic treatment. Toxic and heavy metals such as Hg, Cr, Pb and As were also removed, almost 100%, after 6days of aerobic treatment. A practical method of removal of radioactivity of 10 - 30 μSv/h, caused mainly by radioactive Cs released from the accident at the Daiichi Nuclear Power Plant on 11th March 2011, from sediment mud and soil in Fukushima, Japan, was also carried out. Using immobilized SSI beads, more than 90% and 42% - 73% of radioactive Cs was removed and recovered from sediment mud and soil, respectively, after 3 - 14 days of aerobic treatment in an outdoor 60 L vessel. The weight and mass of the harvested beads could be reduced by more than 97% after desiccation. This technology of removal and recovery had therefore, considerable advantages over other technologies that demanded very large storage facilities in Fukushima. After removal of radioactivity from polluted soil, vegetables like Komatsuna (Turrip leaves) and Chingensai (Green pakchoi) were cultivated on remediated soil. Safe vegetables grown on these treated soils showed a radioactivity content lower than the recommended limit for edible foods in Japan, i.e. less than <100 Bq/kg. Treatment by SSI beads, therefore, appeared to be a compact and suitable technology that could make significant contributions towards agricultural recovery in radioactively polluted areas of Fukushima.
文摘A study on the detection of probable radionuclides and their activity concentrations in the raw material (phosphate rock), final product (fertilizer) and waste samples collected from all the phosphate fertilizer factories (total two factories—A Diammonium Phosphate, DAP and a Triple Super Phosphate, TSP factory) in Bangladesh were carried out. A total of seven types of samples (grossly divided into solid and liquid types);liquid waste, waste-mixed river water, normal river water, phosphate rock, phosphate fertilizer, solid waste and normal soil;were analyzed under this study. Raw material samples were collected only from the TSP fertilizer factory. Fertilizer, solid and liquid waste samples were collected from both the factories under study. Moreover, normal soil and natural surface water samples from the suitable areas adjacent to the factories were also collected for the comparison purpose. The samples were analyzed by gamma ray spectrometry technique using a Hyper-Pure Germanium (HPGe) detector of 40% relative efficiency. The analysis of the samples showed that only natural radionuclides such as 226Ra, 232Th and 40K were present in the samples and no traces of artificial radioactivity were found in any of the samples. 40K was found below the detection limit in some samples. The analysis of the samples in the case of TSP fertilizer factory showed that the average activity concentrations of 226Ra and 232Th and 40K in raw materials were 851.27 ± 7.10, 19.63 ± 6.57 and 54.06 ± 5.93 Bq/kg, respectively, in final product 211.90 ± 4.74, 42.48 ± 10.56 Bq/kg and ND (Not Detected), respectively, in solid waste 187.49 ± 4.88, 70.06 ± 11.76 and 289.27 ± 40.24 Bq/kg, respectively and in liquid waste 6.26 ± 0.63, 10.01 ± 1.39 Bq/L and ND, respectively. The measured results in the case of samples collected from DAP fertilizer factory showed that the average activity concentrations of 226Ra and 232Th and 40K in the final product were 17.31 ± 3.92, 69.74 ± 9.88 and 48.46 ± 17.22 Bq/kg, respectively, in solid waste 24.47 ± 4.15, 164.62 ± 11.08, 191.52 ± 33.74 Bq/kg, respectively and in liquid waste 3.59 ± 1.05, 37.08 ± 3.30 Bq/L and ND, respectively. Considering the stored raw materials and wastes the part of the ambient environment of the factory, radium equivalent activity, radiation hazard index and external annual effective dose to the workers and public due to these materials were also calculated and compared with world average values.
文摘Nine medicinal or herbal plants used in Iraq were analyzed to determine natural radioactivity. The radionuclides were determined by Gross alpha, beta and gamma spectrometry Proportional counter + NaI(Tl) detector type(XLB5) and gamma-ray spectroscopy with (HPGe) techniques. The activity concentration of 40K ranged from 124.1 Bq/kg in (Crust sample) to 88.3 Bq/kg in (Chamomile sample), for gross alpha ranged from (N.D.) in (Flax sample) to 0.4 cpm in (Anise sample), while for beta ranged from 5.7 cpm in (Flax sample) to 25.6 cpm in (Latency sample) and for gamma ranged from 0.6 cpm in (Thyme sample) to 5.10 cpm in (Coriander and Flax samples).
文摘Radioactivity measurements were carried out around Maumba and Nguluku villages, two of the proposed sites for titanium mining in the coastal area of Kenya. Samples of surface soils were analyzed using a HPGe gamma spectrometer. The average activity concentrations for 226Ra, 232Th and 40K are 20.9 ±7.6, 27.6 ± 9.1 and 69.5 ± 16.5 Bqkg–1, respectively. The absorbed dose rates in air, calculated on the basis of the measured activity concentrations, range from 9.8 to 50.0 nGyh-1, with an average of 29.2 nGyh-1. These values are below the global population-weighted mean, and they should be considered when planning appropriate monitoring and surveillance programmes during the mining operation, as well as the reclamation and restoration programmes after mining.
文摘The activity concentrations of naturally occurring 238U, 232Th and 40K in surface soils along Qarun Lake and Wadi El Rayan located in Faiyum, Egypt were determined. The measurements were carried out through gamma-ray spectrometry using a coaxial HPGe detector. The results were compared with those reported in the literature. The radiological hazard radium-equivalent activity index, external and internal indices, radioactivity level index, absorbed dose rate, annual effective dose rate and total absorbed dose rate associated with radioactivity in all samples were evaluated and compared with recommended values. Correlation studies between pairs of radionuclides were performed and discussed.
基金financially supported by International Science&Technology Cooperation Program of China(No.2013DFR90220)Science and Technology Plan of Shandong Province(No.2015GSF115001)
文摘As the traditional methods can not meet the requirements of marine radioactivity monitoring,a radioactivity monitoring sensor used in marine field has been proposed.This sensor is based on Nal(TI) scintillation crystal and employs the special shielding method,the anticoincidence design,the spectrum stabilization algorithm of characteristic peaks and the Monte Carlo simulation fitting calibration formula.Through the continuous tests of terminals and the activity test for target nuclide ^(40)K,it is found that the sensor is stable and the error is less than 10%.
文摘The aim of our present work is to measure the specific activities of the radionuclides 226Ra, 232Th, 40K and the exhalation rates in terms of area and mass of 222Rn in some samples of building materials commonly used in Morocco in order to evaluate the radiological risk caused by natural radioactivity. To this end, the analyses were carried out, using two nuclear techniques, namely high resolution gamma spectrometry and alpha dosimetry based on the use of LR115, on 50 samples collected from large commercial suppliers in Morocco. The results of these analyses show that the average specific activities of 226Ra, 232Th and 40K in these materials vary from 9 to 52 Bq/kg, 3 to 63 Bq/kg and 68 to 705 Bq/kg respectively. These activities remain within the permissible limits of 35 Bq/kg, 30 Bq/kg and 370 Bq/kg respectively, with the exception of a few samples of red brick, gray cement, ceramic and granite. The activity of the radium equivalent (Raeq), the internal (Hin) and external (Hex) hazard indices, the absorbed dose rate, the total annual effective dose , the excess lifetime cancer risk (ELCR) as well as volumic activities, exhalation rates in terms of area (ES) and mass (EM) are calculated for the samples analyzed in this work in order to assess the radiological risks resulting from the use of these materials in various construction activities. It seems that the values of these indices vary from 19 to 196 Bq/kg, 0.08 to 0.67, 0.05 to 0.53, 9 to 91 nGy/h, 0.05 to 0.56 mSv/y, 0.19 × 10−3 to 1.96 × 10−3, 72 to 350 Bq/m3, 56 to 273 mBq⋅m−2⋅h−1 and 3 to 15 mBq⋅kg−1⋅h−1 respectively. The lowest values are identified for gypsum, while the highest are attributed to granite. All of the obtained results of these indices respect the permissible limits except for the Raeq in some granite samples, the ELCR index in all samples except gypsum and the radon volumic activity in some gray cement samples, ceramic and granite. As a result, the different types of building materials analyzed in our work do not present a health risk to the public and can be used in various construction activities, with the exception of a few samples of red brick, gray cement, ceramic and granite. The choice of the use of red brick, gray cement and ceramic should be monitored and adapted according to the criteria of the limitation of the doses whereas the use of the granite must be moderate in order to limit over time the health risk which increases with the duration of exposure of humans to these building materials.
文摘The experimental detection of the hidden periodicities in the activity of various radioactive sources which were observed by different instruments and which coincided with the period of the free oscillations of the Sun gave an impetus to the further research. The simultaneous recording of gamma rays from two radioactive sources revealed the elements of synchronism and the periods of solar oscillations as well as the phase delay for the different sources in the obtained time series. A neutrino detector has been designed and tested, the advanced schemes for neutrino detection are developed, and the impact of the neutrino source on the radioactive matter is explored. The search for the new principles for creating the emitters of neutrino beams is conducted.
文摘<p> The concentrations and distribution of naturally occurring radionuclides <span><span><span><span>(</span><sup><span>238</span></sup><span>U, </span><sup><span>235</span></sup><span>U, </span><sup><span>234</span></sup><span>U, </span><sup><span>230</span></sup><span>Th, </span><sup><span>226</span></sup><span>Ra, </span><sup><span>210</span></sup><span>Pb, </span><sup><span>232</span></sup><span>Th, </span><sup><span>228</span></sup><span>Ra, and </span><sup><span>40</span></sup><span>K)</span></span></span></span><span><span><span><span> were determined by alpha and gamma spectrometry in soil and sediments collected from Luilu and Dilala rivers located in the mining district of Kolwezi (Lualaba Province) of the Democratic Republic of the Congo. The average concentrations of </span><sup><span>238</span></sup><span>U and </span><sup><span>226</span></sup><span>Ra in the analyzed samples were 5</span></span></span></span><span><span><span> </span></span></span><span><span><span>-</span></span></span><span><span><span> </span></span></span><span><span><span>10 times higher than the world average values for soil provided by the </span></span></span><span><span><span>United Nations Scientific Committee on the Effects of Atomic Radiation. However,</span></span></span><span><span><span><span> the average concentrations of </span><sup><span>232</span></sup><span>Th were found similar to the world average. In both river basins, artisanal mining activities and</span></span></span></span><span><span><span> mineral washing sites displayed the higher concentration values of radionuclides. The mean values of health risk indices calculated for those sites were found sig</span></span></span><span><span><span>nificantly higher compared to world average levels. Radiation protection measures seem needed to ensure the radiation safety of local populations.</span></span></span> </p> <p> <span><span><span><br /> </span></span></span> </p> <p> <span style="font-size:16px;"><strong>Graphical Abstract</strong></span> </p> <p> <span><span><span><img src="Edit_7a1bf87c-f0a0-4c34-80b2-7e488ac5e4a2.png" alt="" /><br /> </span></span></span> </p>
