Absorbed dose rate assessment for the Japanese cedar stand affected after the Fukushima NPP accident.

2021 ◽  
Author(s):  
Rena Mikailova ◽  
Yuichi Onda ◽  
Sergey Fesenko ◽  
Hiroaki Kato
Keyword(s):  
Dose Rate ◽  
Water Content ◽  
Forest Ecosystem ◽  
Forest Ecosystems ◽  
Absorbed Dose ◽  
Japanese Cedar ◽  
Average Dose ◽  
High Concentration ◽  
Absorbed Dose Rate ◽  
Dose Rates

<p>The nuclear disaster from the FNPP accident resulted in the major contamination of forest ecosystem of Eastern Japan. Forests are the most susceptible to ionizing radiation exposure, especially conifers due to their high radiosensitivity and pollutant interception abilities. A high concentration of radionuclides in forest ecosystems caused an increase in the dose rate. Japanese cedar belongs to Japan's endemic species; therefore, the current study was aimed at the absorbed dose rate assessment of the C. japonica forest stand in the Yamakiya district. To estimate the absorbed dose rates to the Japanese cedar trees, we used the <sup>134,137</sup>Cs concentrations in different forest ecosystems’ compartments. The calculations include data from 2011 to 2017. The dose rate assessments were performed at different heights of the forest ecosystem (canopy, trunk, understory). The average dose rates decreased from 40 µGy/day in 2011 to 13 µGy/day in 2017. The assessment results comply with the ambient dose rate measured from 2011 to 2015. The assessment showed that the water content in the litter and topsoil layers significantly influence the formation of the dose rate. Via the model, we simulated the dose rates for 20% and 80% of the litter water content. The results showed that the average measured dose rates lie within the estimated results. Due to the lack of data on litter and soil moisture during sampling, now we are trying to calculate the ground layers’ water content using the available information on precipitation rate.</p>

scholarly journals Activity of natural radionuclides and their contribution to the absorbed dose in the fish cubera snapper (lutjanus cyanopterus, cuvier, 1828) on the coast of Ceara, Brazil

2010 ◽  
Vol 58 (spe4) ◽  
pp. 25-32 ◽  
Author(s):  
Wagner de S. Pereira ◽  
Alphonse Kelecom ◽  
Delcy de A. Py Júnior
Keyword(s):  
Dose Rate ◽  
Standard Dose ◽  
Natural Radionuclides ◽  
Absorbed Dose ◽  
Threshold Value ◽  
Average Dose ◽  
Absorbed Dose Rate ◽  
Dose Rates ◽  
A Value ◽  
Lead 210

A methodology was developed for converting the activity concentration of radionuclides (Bq kg-1) into absorbed dose rate (Gy y-1), aiming an approach to environmental radioprotection based on the concept of standard dose limit. The model considers only the internal absorbed dose rate. This methodology was applied to the cubera snapper fish (Lutjanus cyanopterus, Cuvier, 1828) caught off the coast of Ceará. The natural radionuclides considered were uranium-238, radium-226, lead-210, thorium-232 and radium-228. The absorbed dose rates were calculated for individual radionuclides and the type of emitted radiation. The average dose rate due to these radionuclides was 5.36 µGy y-1, a value six orders of magnitude smaller than the threshold value of absorbed dose rate used in this study (3.65 10³ mGy y-1), and similar to that found in the literature for benthic fish. Ra-226 and U-238 contributed 67% and 22% of the absorbed dose rate, followed by Th-232 with 10%. Ra-228 and Pb-210, in turn, accounted for less than 1% of the absorbed dose rate. This distribution is somewhat different from that reported in the literature, where the Ra-226 accounts for 86% of the absorbed dose rate.

scholarly journals Influences of Absorbed Dose Rate on the Mechanical Properties and Fiber–Matrix Interaction of High-Density Polyethylene-Based Carbon Fiber Reinforced Thermoplastic Irradiated by Electron-Beam

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3012
Author(s):  
Se Kye Park ◽  
Dong Yun Choi ◽  
Duyoung Choi ◽  
Dong Yun Lee ◽  
Seung Hwa Yoo
Keyword(s):  
Mechanical Properties ◽  
Electron Beam ◽  
Carbon Fiber ◽  
Dose Rate ◽  
High Density Polyethylene ◽  
Absorbed Dose ◽  
High Density ◽  
Absorbed Dose Rate ◽  
Dose Rates ◽  
Absorbed Dose Rates

In this study, a high-density polyethylene (HDPE)-based carbon fiber-reinforced thermoplastic (CFRTP) was irradiated by an electron-beam. To assess the absorbed dose rate influence on its mechanical properties, the beam energy and absorbed dose were fixed, while the absorbed dose rates were varied. The tensile strength (TS) and Young’s modulus (YM) were evaluated. The irradiated CFRTP TS increased at absorbed dose rates of up to 6.8 kGy/s and decreased at higher rates. YM showed no meaningful differences. For CFRTPs constituents, the carbon fiber (CF) TS gradually increased, while the HDPE TS decreased slightly as the absorbed dose rates increased. The OH intermolecular bond was strongly developed in irradiated CFRTP at low absorbed dose rates and gradually declined when increasing those rates. X-ray photoelectron spectroscopy analysis revealed that the oxygen content of irradiated CFRTPs decreased with increasing absorbed dose rate due to the shorter irradiation time at higher dose rates. In conclusion, from the TS viewpoint, opposite effects occurred when increasing the absorbed dose rate: a favorable increase in CF TS and adverse decline of attractive hydrogen bonding interactions between HDPE and CF for CFRTPs TS. Therefore, the irradiated CFRTP TS was maximized at an optimum absorbed dose rate of 6.8 kGy/s.

CHANGES OF ABSORBED DOSE RATE IN AIR BY CAR-BORNE SURVEY IN NAMIE TOWN, FUKUSHIMA PREFECTURE AFTER THE FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT

2019 ◽  
Vol 184 (3-4) ◽  
pp. 527-530 ◽  
Author(s):  
Y Shiroma ◽  
M Hosoda ◽  
K Iwaoka ◽  
M Hegedűs ◽  
H Kudo ◽  
...  
Keyword(s):  
Power Plant ◽  
Dose Rate ◽  
Nuclear Power ◽  
Absorbed Dose ◽  
Local Distribution ◽  
Absorbed Dose Rate ◽  
Distribution Maps ◽  
Dose Rates ◽  
Fdnpp Accident ◽  
Fukushima Daiichi

Abstract The latest car-borne survey was carried out by Hirosaki University in order to grasp the local distribution of the absorbed dose rate in air after the evacuation order was lifted on Namie Town in 2017. The car-borne survey of absorbed dose rate in air was carried out on most of the roads which were accessible by car in Namie Town using a 3-in × 3-in NaI(Tl) scintillation spectrometer. The range of the absorbed dose rate in air was calculated to be 0.041–11 μGy h−1. The distribution maps of the absorbed dose rate in air were drawn based on the data obtained during the surveys in 2011, 2015 and 2017. The comparison of these absorbed dose rates in air suggests that the elevated absorbed dose rate in air in Namie Town caused by the FDNPP accident may be decreasing faster than natural decline which includes weathering effect and physical decay due to the artificial decontamination.

EVALUATION OF INDOOR/OUTDOOR GAMMA EXPOSURE RATES AND EXCESS LIFE TIME CANCER RISK IN DIFFERENT CITIES OF PAKISTAN

2020 ◽  
Vol 190 (4) ◽  
pp. 355-363
Author(s):  
Jahan Zeb ◽  
Mohammad Wasim ◽  
Muhammad Awais ◽  
Asad Ullah ◽  
Talat Iqbal ◽  
...  
Keyword(s):  
Cancer Risk ◽  
Dose Rate ◽  
Absorbed Dose ◽  
Life Time ◽  
Absorbed Dose Rate ◽  
Detailed Measurement ◽  
Dose Rates ◽  
The Mean ◽  
Azad Kashmir ◽  
Indoor And Outdoor

Abstract This study presents a detailed measurement of indoor and outdoor terrestrial gamma radiation levels in different cities of Pakistan. The measurements covered dwellings in 27 cities, covering all provinces and region of Azad Kashmir. Most of the houses were of attached type, made of brick walls and concrete roofs. The measurements were made by a handheld radiation survey meter containing Geiger–Muller tube. The average absorbed dose rate in air was 100 ± 32 nGy h−1 for indoor and 74 ± 30 nGy h−1 for outdoor. The population-weighted mean terrestrial dose rates were 90 nGy h−1 for indoor and 78 nGyh−1 for outdoor. The ratio of indoor to outdoor absorbed dose rate was 1.5 as compared to 1.3 for the world average. The estimated average annual effective dose rate was 0.58 ± 0.18 mSv a−1 and the mean excess life time cancer risk was 2.0 × 10−3.

IMPACT ON ABSORBED DOSE RATE IN AIR IN KANTO REGION BY FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT

2019 ◽  
Vol 184 (3-4) ◽  
pp. 500-503
Author(s):  
K Inoue ◽  
M Arai ◽  
H Tsuruoka ◽  
K Saito ◽  
M Fujisawa ◽  
...  
Keyword(s):  
Dose Rate ◽  
Nuclear Power ◽  
Absorbed Dose ◽  
Ground Level ◽  
Absorbed Dose Rate ◽  
Artificial Radionuclides ◽  
Dose Rates ◽  
The Mean ◽  
Absorbed Dose Rates ◽  
Kanto Region

Abstract Absorbed dose rates in air were measured for the whole area of the Kanto region in 2015, 2016 and 2017 (n = 31 147). The mean absorbed dose rates in air for each prefecture measured by car-borne surveys were from 44 to 67 nGy h−1 (13–289 nGy h−1). The absorbed dose rate in air from artificial radionuclides (134Cs + 137Cs) measured by fixed-point observation (n = 507) was from 1 to 14 nGy h−1 (0–105 nGy h−1), and meaning that the contribution ratios of 134Cs and 137Cs were 3–22%. The deposited location of artificial radionuclides was less than 1000 m from ground level and depended on the topography, wind direction and precipitation field.

Natural gamma radiation in La Palma Island, Canary Islands, Spain

2020 ◽  
Author(s):  
María López-Pérez ◽  
Pedro Ángel Salazar-Carballo ◽  
M. Candelaría Martín-Luis ◽  
José Miguel Lorenzo-Salazar ◽  
Xiomara Duarte-Rodríguez ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Dose Rate ◽  
Canary Islands ◽  
Absorbed Dose ◽  
Absorbed Dose Rate ◽  
Dose Rates ◽  
La Palma ◽  
Natural Gamma ◽  
Gamma Absorbed Dose ◽  
Cumbre Vieja

<p>The Canary Islands are an archipelago with an area of 7,447 km<sup>2</sup> comprising seven main islands and some islets, located about 90 km off the northwest coast of Africa. La Palma is the most active volcanic island of the Canarian archipelago in historical times (after XV Century), with an area of 706 km<sup>2</sup> and about 83,000 inhabitants. From the geochemical point of view, La Palma is characterized by alkaline rocks ranging from basanites and alkali picrites to phonolites. Despite the different geological units essentially overlap in their bulk chemical compositions, there are significant differences.</p><p>Measurements of natural gamma radiation were carried out in 71 sites randomly selected on a predefined 3x3 km sampling grid covering the whole island in 2013. Total outdoor gamma radiation levels were measured at 1 m above the ground. Air gamma radiation was measured by means of a MINI 6-80 (Mini-Instruments) monitor equipped with an energy-compensated Geiger-Müller MC-71 probe and FH 40 GL 10 (ThermoFischer Scientific) dosimeter equipped with a proportional-gas detector. The background radiation was calculated for each sampling site and subtracted for each dose measurement. Additionally, 25 soil samples were collected at a depth of 0-15 cm in uncultivated fields. Radiometric measurements for <sup>40</sup>K, <sup>226</sup>Ra and <sup>232</sup>Th radioisotopes were performed by low-level gamma spectrometry with coaxial-type germanium detectors (Canberra Industries Inc., USA).</p><p>The gamma absorbed dose rates showed a log-normal distribution, ranging from 37.2 up to 134.0 nGy·h<sup>-1</sup>, with a geometric mean of 64.5 nGy·h<sup>-1</sup>. The observed mean gamma absorbed dose rate in La Palma Island was higher than those measured in La Gomera Island (43.9 nGy·h<sup>-1</sup>), and lower than those measured in Tenerife (89.2 nGy·h<sup>-1</sup>) and El Hierro islands (93.3 nGy·h<sup>-1</sup>) (publication in preparation). The geometric means of <sup>40</sup>K, <sup>226</sup>Ra and <sup>232</sup>Th activity concentration were 216.1 Bq·Kg<sup>-1</sup>, 22.0 Bq·Kg<sup>-1</sup> and 23.6 Bq·Kg<sup>-1</sup>, respectively.</p><p>Maps with the spatial distribution of the terrestrial natural gamma radiation and <sup>40</sup>K, <sup>226</sup>Ra and <sup>232</sup>Th radioisotopes were also prepared and compared with the geochemical composition of soils. Contour maps for the terrestrial radiation component of the absorbed dose rate and radioisotope distributions were obtained using ordinary Kriging interpolation. Lower absorbed dose rates (between 45 and 70 nGy h<sup>-1</sup>) were observed in the oldest northern part of the island, corresponding to the Taburiente and Garafía basaltic shields. Two anomalies were found with absorbed dose rate values between 80 and 110 nGy h<sup>-1</sup>. The first one is located at the Bejenado stratovolcano, extending north to the Caldera de Taburiente, and south to the Aridane Valley. The second anomaly was found in the southeastern part of the Cumbre Vieja ridge. This last volcanic edifice corresponds to the youngest part of the island, where several historical eruptions have occurred. These anomalies might be related to phonotrephritic and phonolitic rocks identified at the upper part of the Bejenado sequence and Cumbre Vieja edifice.</p><p> </p>

EFFECT OF BUILDUP FACTORS ON INDOOR GAMMA DOSE RATE

2020 ◽  
Vol 190 (2) ◽  
pp. 132-138
Author(s):  
V Manić ◽  
G Manić ◽  
D Nikezić ◽  
D Krstić
Keyword(s):  
Effective Dose ◽  
Dose Rate ◽  
Gamma Rays ◽  
Building Materials ◽  
Absorbed Dose ◽  
Gamma Dose ◽  
Gamma Dose Rate ◽  
Absorbed Dose Rate ◽  
Dose Rates ◽  
Buildup Factors

Abstract The effect of buildup factors on absorbed dose rate in air and the effective dose from gamma rays of primordial radionuclides in building materials, was investigated in the article. Specific absorbed dose rates were calculated for the standard concrete room, as well as, for rooms where brick and covering building materials were used. For all room models the Harima (G-P) buildup factors were applied, while for the standard room the Berger’s and Taylor’s buildup factors were used, too. The contribution of the radiation buildup to absorbed dose rate and effective dose was determined as large as 41%.

scholarly journals Thermoluminescent and X-ray diffraction methods in dating of ceramics from archaeological excavations of the Orikti monument (Almaty region)

2020 ◽  
pp. 4-10
Author(s):  
Askar Bakhadur ◽  
Nadezhda Aluker ◽  
Galymzhan Bekseitov ◽  
Yerbolat Ospanov ◽  
Bolat Uralbekov
Keyword(s):  
Dose Rate ◽  
Dose Range ◽  
Sampling Site ◽  
Absorbed Dose ◽  
Average Dose ◽  
Preparation Technique ◽  
X Ray Diffraction ◽  
Absorbed Dose Rate ◽  
X Ray ◽  
Ceramic Samples

In this work, the ages of archaeological ceramics were determined by the thermoluminescent method after X-ray diffraction analysis (XRD) of ceramic samples, which confirms that quartz is the main component phase of the products. This allowed to use the sample preparation technique without isolating the quartz phase from the ceramic sample. Silicon oxide based soil-equivalent thermoluminescent detectors were used to determine the annual absorbed dose rate at the sampling site. The average dose rate at sampling site was 0.62 ± 0.02 cGy/year. Calculation of the ceramics ages was carried out after checking the linearity of lightsums accumulation for samples in the dose range up to 2000 cGy. Based on the performed studies, the ages of the ceramic products were determined that do not contradict to archaeologists dating of these products. It is proposed to use the procedure for determining ceramic samples by the thermoluminescent method after their phase composition identification by XRD. In the case of the predominant mineral composition of quartz phase (the proportion of quartz is more than 60% of the total composition of ceramics), the measurements can be carried out without the quartz isolating; while presence of clay mineral fractions commensurate with quartz levels can lead to the separation of the quartz.

scholarly journals Radioactivity of soil in Croatia II: 137Cs, 40K, and absorbed dose rate

2021 ◽  
Vol 72 (1) ◽  
pp. 15-22
Author(s):  
Marko Šoštarić ◽  
Branko Petrinec ◽  
Mak Avdić ◽  
Ljerka Petroci ◽  
Milica Kovačić ◽  
...  
Keyword(s):  
Dose Rate ◽  
Gamma Ray ◽  
Absorbed Dose ◽  
Gamma Ray Spectrometry ◽  
External Exposure ◽  
Vegetation Density ◽  
Absorbed Dose Rate ◽  
Dose Rates ◽  
Activity Concentrations ◽  
Uncultivated Soil

Abstract We took samples of uncultivated soil from the surface layer (0–10 cm) at 138 sites from all over Croatia and measured their radionuclide activity concentrations with high-resolution gamma-ray spectrometry. This second part of our report brings the results on 40K and 137Cs to complement those on the 232Th and 238U decay chains addressed in the first part. Together they give the most complete picture of radioactivity of Croatian soil so far. Activity concentrations of 40K were the highest in the Pannonian region, and there was an opposite trend for 137Cs. We found that the concentrations of 137Cs tended to increase with altitude, annual precipitation, and vegetation density. The concentration ratio of 137Cs and K in soil, which indicates the potential for 137Cs entering food chains via uptake by plants, was the lowest in agriculturally important areas in the east of the Pannonian region. In addition, we used the obtained results on activity concentrations to calculate the related absorbed dose rate as a measure of external exposure to ionising radiation from soil. The sum of the absorbed dose rates for naturally occurring radionuclides and 137Cs showed that external exposure was generally the highest in the Dinaric region and Istrian Peninsula.

scholarly journals Reconstruction of the absorbed dose of ionizing radiation for helophytes in the water bodies of the near emergency zone at the Chornobyl NPP

2020 ◽  
Vol 21 (4) ◽  
pp. 338-346
Author(s):  
V.V. Belyaev ◽  
◽  
O.M. Volkova ◽  
D.I. Gudkov ◽  
S.P. Pryshlyak
Keyword(s):  
Ionizing Radiation ◽  
Dose Rate ◽  
Absorbed Dose ◽  
Growing Season ◽  
Plant Roots ◽  
Average Dose ◽  
Exclusion Zone ◽  
Absorbed Dose Rate ◽  
Radionuclide Content ◽  
Biological Dose

Based on modeling the dynamics of the Chornobyl emission radionuclide content in the components of the most polluted reservoirs of the Chornobyl Exclusion Zone, the absorbed dose for helophytes was reconstructed. During the growing season of 1986, the absorbed dose of plants of Glyboke Lake was 78 Gy, Daleke Lake 39 Gy. The absorbed dose rate of plant roots was 2.4 times higher than that of aboveground organs. According to actual data, in the period 2016 - 2019 in the Glyboke Lake average dose of external and internal plant irradiation was about 7.5 mGy/year, and in the Daleke Lake 5.6 mGy/year. On abnormally contaminated sections of the Glyboke Lake, the external dose reaches 0.5 - 1.0 Gy/year. During the period 1986 - 2020, the maximum cumulative (biological) dose of helophytes of Glyboke Lake can be 190 Gy, Daleke Lake 80 - 85 Gy.

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