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Advance on monitoring of Radioactivity in food in China and Japan after Fukushima nuclear accident

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Radiation Medicine and Protection 2022年第1期3卷 37-42页

作者： Shuying Kong Baolu Yang Fei Tuo Tianxiang Lu National Institute for Radiological Protection Chinese Center for Disease Control and PreventionKey Laboratory of Radiological Protection and Nuclear EmergencyChina CDCBeijing 100088China

After the nuclear accident at the Fukushima Daiichi Nuclear Power Plant(Fukushima nuclear accident)in 2011,Japan quickly took emergency measures to reduce radiation hazards posed by the released radioactive materials.As a neighboring country of Japan across the East China Sea,China has also taken some corresponding prevention and control measures.China has continuously strengthened the monitoring of Radioactivity in food in recent years.This paper discusses the revision of standards for Radioactivity in food,the improvement of methods and equipment,and the updating of monitoring systems performed in China and Japan over the last ten years after the Fukushima Daiichi accident.In addition,this paper outlines the recent problems left over from the nuclear accident,puts forward some views on the progress of important topics,and gives some thoughts and prospects on the further improvement of the monitoring systems of Radioactivity in food in China.

关键词： Food monitoring Radioactivity Fukushima nuclear accident

Petrogenesis,Geodynamics and Radioactivity of the Granitic Rocks of the Nugrus Weakness Zone,South Eastern Desert,Egypt

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1183-1198页

作者： Soliman ABU ELATTA Abdallah Mahmoud Gehad M.R.MANSOUR Nuclear Materials Authority CairoEgypt.P.O.Box 530 El Maadi

The studied granitic bodies belong to the south Eastern Desert of Egypt.They extend in a NNW–SSE trend along the same strike of the Nugrus weakness zone by which they are structurally controlled.These rocks are composed of biotite and biotite-muscovite monzogranites to syenogranites.Geochemically,a higher abundance of Ba and Rb in biotite granites with a relatively low abundance in biotite-muscovite granites as well as the diversity of Th,U,Nb,Ta,Zr,and REE reflects their origin from different sources and geodynamic settings.The biotite granites are predominantly metaluminous to low peraluminous whereas the biotite-muscovite granites have a peraluminous nature.Potassium enrichment at the expense of calcium in these rocks reflects a derivation from crustal sources by partial melting in the presence of a volatile system.Radiometric investigation showed high abundances of U(up to 38 ppm)and Th(up to 26 ppm)in biotite-muscovite granites relative to biotite granites(up to 5 ppm U and 18 ppm Th).Radioactive anomalies furthermore have been recorded in parts of biotite-muscovite granites that were affected by the faults(up to 116 ppm eU and 97 ppm eTh).Consequently,biotite-muscovite granites form a potentially fertile source for uranium mineralization.

关键词： partial melting biotite-muscovite granites peraluminous geodynamic Radioactivity Nugrus

The gross α and β Radioactivity levels of drinking water source in one oil industrial city in northeast China

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Radiation Medicine and Protection 2021年第2期2卷 61-66页

作者： Yan Shi Wa Gao Tuya Siqin Zhigang Li Jianwei Zhang Rongshu Guan Jinfeng Li Peilin Sun Hongtao Zhao Key Laboratory of Nuclear Technology Application Institute of Technical PhysicsHeilongjiang Academy of SciencesHarbin150086China

Objective:To investigate the grossαandβRadioactivity levels of drinking water source in the city,the largest oil field production base in northeast China,in order to ensure the safety of drinking water and public health.Methods:The water samples from three drinking water sources were collected and tested in the dry and wet season,respectively.The grossαRadioactivity was measured by standard curve method,grossβwas measured by thin sample method.Results:Totally 184 samples were collected from the three sampling areas in dry and wet season respectively.The average values of grossαandβRadioactivity levels in the drinking water source area were(0.24±0.09)and(0.30±0.17)Bq/L respectively.The average activity concentration of grossαand grossβin the dry season was(0.23±0.09)and(0.29±0.18)Bq/L,respectively.The grossαandβRadioactivity levels gradually decreased from the intake to the end of the reservoir of drinking water source areas.Conclusions:The grossαandβRadioactivity levels and distribution of drinking water source areas in this city were all lower than the drinking water limit issued by China and the reference level recommended by the World Health Organization.The Radioactivity of water body of the drinking water source was within the normal background level.

关键词： Water source Grossα Grossβ Radioactivity

Simulation of induced Radioactivity for a heavy ion medical machine

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Chinese Physics C 2014年第11期38卷 111-114页

作者：徐俊奎苏有武李武元毛旺夏佳文陈熙萌严维伟徐翀 School of Nuclear Science and Technology Lanzhou University Institute of Modern Physics Chinese Academy of Science

The Radioactivity induced by carbon ions of the Heavy Ion Medical Machine （HIMM） was studied to asses its radiation protection and environmental impact. Radionuclides in the accelerator component, and in the cooling water and air at the target area, which are induced from primary beam and secondary particles, are simulated by FLUKA Monte Carlo code. It is found that Radioactivity in the cooling water and air is not very important at the required beam intensity and energy that is needed for treatment, while radionuclides in the accelerator component may cause some problems for maintenance work and, therefore, a suitable cooling time is needed after the machine is shut down.

关键词： Radioactivity HIMM heavy ion

Study on induced Radioactivity of China Spallation Neutron Source

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Chinese Physics C 2011年第6期35卷 596-602页

作者：吴青彪王庆斌吴靖民马忠剑 Institute of High Energy Physics Chinese Academy of Sciences

China Spallation Neutron Source （CSNS） is the first High Energy Intense Proton Accelerator planned to be constructed in China during the State Eleventh Five-Year Plan period, whose induced Radioactivity is very important for occupational disease hazard assessment and environmental impact assessment. Adopting the FLUKA code, the authors have constructed a cylinder-tunnel geometric model and a line-source sampling physical model, deduced proper formulas to calculate air activation, and analyzed various issues with regard to the activation of different tunnel parts. The results show that the environmental impact resulting from induced activation is negligible, whereas the residual radiation in the tunnels has a great influence on maintenance personnel, so strict measures should be adopted.

关键词： CSNS Radioactivity FLUKA dose line-source

Calculations of Radioactivity and afterheat in the components of the CSNS target station

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Chinese Physics B 2009年第9期18卷 3815-3818页

作者：于全芝梁天骄殷雯严启伟贾学军王芳卫 CSNS Engineering Center for Target Station and Instruments Institute of PhysicsChinese Academy of Sciences

This paper shows the calculations of Radioactivity and afterheat in the components of the China Spallation Neutron Source （CSNS） target station, with the Monte Carlo codes LAHET, MCNP4C and the multigroup code CINDER＇90. These calculations provide essential data for the detailed design and maintenance of the CSNS target station.

关键词： Monte Carlo codes Radioactivity afterheat CSNS target station

Induced Radioactivity at particle accelerators:a short review

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Radiation Detection Technology and Methods 2021年第4期5卷 481-492页

作者： Shakhboz Khasanov Bo Yang Youwu Su Akmal Safarov Yao Yang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Samarkand State University SamarkandUzbekistan140104 Institute of Advanced Science Facilities Shenzhen 518107China

Purpose The induced Radioactivity in accelerator components and decay characteristics of radioactive nuclei contained therein is critical for radiation safety of occupational workers as well as for the maintenance,repair,and decommissioning activities.The topic of induced Radioactivity is widely reported and extensively explored in the literature by many researchers up to now.This mini-review would demonstrate the current state of the knowledge on induced Radioactivity at particle accelerators.Methods In this article,the concepts of activation-related studies and radionuclide generation in accelerator environments are reviewed.In addition,some studies on accelerator-induced Radioactivity by Monte Carlo and experimental measurement methods are briefly described.Results and conclusions The possible radiation protection problems caused by particle accelerator-induced Radioactivity are briefly reviewed and analyzed.The produced radionuclides depend on the beam parameters such as particle type,energy,irradiation period,cooling time,and irradiated material.The Monte Carlo simulation method offers comparable advantages over empirical analysis method.A review of major studies in the field of induced Radioactivity of particle accelerators confirmed that the extremely strong induced Radioactivity generated at hot spots of accelerators means new challenges to radiation safety and deserves further investigation and discussion.

关键词： Accelerators Radioactivity Monte Carlo Radiation protection

Natural Radioactivity measurements of frozen red meat samples consumed in Iraq

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Radiation Detection Technology and Methods 2019年第4期3卷 1-4页

作者： Murtadha Sh.Aswood Ali Abid Abojassim Mustafa Salih Ali Al Musawi Department of Physics College of EducationUniversity of Al-QadisiyahAl DiwaniyahIraq Department of Physics Faculty of ScienceUniversity of KufaNajafIraq Department of Physiology College of MedicineAl-Mustansiriyah UniversityBaghdadIraq

Purpose In the present study,the activity concentrations of long-lived gamma-ray emitters(^(238)U,^(232)Th and ^(40)K)in ten dif-ferent types of frozen red meat samples selected from markets in Iraq were measured.Methods The technique of gamma spectrometer equipped with scintillation detector NaI(Tl)was used.Results The annual effective dose was estimated in adults and kids.The results showed that the concentrations of ^(238)U,^(232)Th and ^(40)K were found in the range of permissible limits of 30,32 and 400 Bq kg−1,respectively.On the other hand,the maximum values of ^(238)U and ^(232)Th in beef samples are higher than in lamb meat samples.The annual effective dose of adults and kids was observed to be below the limit(1.0 mSv)recommended by ICRP.Conclusion The frozen red meat samples are safe for human consumption and have gamma-ray emitter concentrations lower than the maximum permissible levels.

关键词： Radioactivity Annual effective dose Frozen red meats Iraq

Assessment of Natural Radioactivity Levels and Radiation Dose Rate in Some Soil Samples from Historical Area, AL-RAKKAH, Saudi Arabia

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Natural Science 2015年第5期7卷 238-247页

作者： K. S. Al Mugren Physics Department Faculty of Sciences Princess Nourah Bint Abdulrahman University Riyadh Saudi Arabia

This study aims to determine the activity concentrations of naturally occurring, technically-enhanced levels of radiation and the gamma absorbed dose rates in soil samples collected across the land scape of historical area which discovered in east of Saudi Arabia at 2009 G, Called AL- RAKKAH. By using an HPGe detector gamma-ray spectrometer, the activity concentrations of 226Ra 232Th and 40K were found in surface soil samples ranged from 17. 4 ± 1.2 Bq/kg to 28.3 ± 2.3 Bq/kg with an average value of 23 ± 1.6 Bq/kg, ranging from 1.1 ± 1.8 Bq/kg to 81.0 ± 1.7 Bq/kg with the average value 20 ± 1.4 Bq/kg and from 218 ± 11 Bq/kg to 255 ± 18 Bq/kg, with the mean value of 233 ± 12 Bq/kg respectively. The mean radium equivalent (Raeq) and outdoor radiation hazard index (Hex) for the area under study were determined as 69.52 Bq/kg and 0.16 respectively. The total absorbed dose rate due to three primordial radionuclides lies in the range of 17.74 - 72.24 nGy·h-1 with a mean of 32.69 nGy·h-1, which yields total annual effective dose of 0.37 mSv·y-1. The measured values are comparable with other global Radioactivity measurements and are found to be safe for public and environment. The baseline data of this type will almost certainly be of importance in making estimations of population exposure.

关键词： Soil Gamma Ray Spectroscopy Radioactivity Dose Rate Alrakkah Saudi Arabia