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1

Contribution of soil in the annual effective dose due to radon in the air of some dwellings in the city of Karbala, Iraq

Hashim Abdalsattar Kareem, Najam Laith Ahmed, Aljomaily Firas Mohammed Ali

Polish Journal of Medical Physics and Engineering

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2021

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Vol. 27, Iss. 3

233--239

EN

Introduction: The radon isotopes are not as significant as (222Rn) due to the decay of the natural radionuclides (235U), (232Th) and (238U) due to their short half-life, at most. (222Rn) can be classified as among the most harmful radioactive elements in the world. Material and method: In this analysis, the closed-can technique was used with solid-state nuclear track detectors (CR- 39). After forty days of closed dosimeter buried in the soil of the garden, and ninety days from the closed position in the air of some dwellings were collected dosimeter and stripped of nuclear detectors impact of closed groups. For 8 hours, CR-39 detectors were chemically etched by (6.25 N) NaOH solution at 70°C and then registered within an optical microscope. Result: The levels of soil radon concentrations ranged from 28.44±0.58 to 479.76±2.43 Bq/m3 with a mean value of 220.33±1.64 Bq/m3, while the concentration of radon in the air of certain dwellings varied from (1.95±0.27 to 46.82±0.75) Bq/m3 with an average value of 21.51±0.54 Bq/m3. In comparison, the annual effective dose attributed to radon in soil ranged from 0.71±0.09 mSv/y to 12.10±0.38 mSv/y with an average value of 5.55±0.261 mSv/y, while the annual effective dose in air differed from (0.04±0.02 mSv/y) to (1.18±0.12 mSv/y) with an average value of (0.60±0.09 mSv/y). Conclusion: Neglecting the effects of other radon sources, the percentage share of the annual effective dose due to radon in soil measured in the air home, ranged from 0.005±0.001 to 0.453±0.074 with an average value of 0.130±0.040. Weak correlation between concentrations of radon in households and soil air. But roughly speaking, one can say that in soil air every 1000 Bq/m3 and 1000 mSv/y contributes around 130 Bq/m3 and 130 mSv/y in indoor air.

2

Effect of gender and occupations on uranium concentration in human blood and soil samples collected from Babylon, Iraq

Showard Ansam F., Aswood Murtadha Sh.

Polish Journal of Medical Physics and Engineering

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2020

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Vol. 26, Iss. 3

143--148

EN

Uranium concentrations of human blood and soil samples have been studied at different ages and occupations in Babylon, Iraq. The technique of nuclear track detectors CR 39 with nuclear fission track analysis has been used to determine the uranium concentrations in this study. Results have shown that the concentrations of uranium ranged from 0.56 ± 0.06 to 1.24 ± 0.29 ppb with an average of 0.83 ± 0.18 ppb in blood samples. On the other hand, the concentrations of uranium in soil samples ranged from 0.93 ± 0.20 to 2.59 ± 0.15 ppm with an average of 1.72 ± 0.19 ppm. Moreover, the highest averages of concentration have been found in the city center of Babylon, reaching 1.09 ± 0.22 ppb and 2.10 ± 0.23 ppm in blood and soil samples, respectively. The results have further proved that gender and occupations have an effect in increasing the concentrations of uranium. In addition, the concentrations in blood samples are generally lower than the concentration in soil samples.

3

Exposures from radon, thoron, and thoron progeny in high background radiation area in Takandeang, Mamuju, Indonesia

Saputra Miki Arian, Nugraha Eka Djatnika, Purwanti Tri, Arifianto Rokhmat, Laksmana Roza Indra, Hutabarat Richard P., Hosoda Masahiro, Tokonami Shinji

Nukleonika

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2020

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Vol. 65, No. 2

89--94

EN

The exposure from radon, thoron, and thoron progeny was measured for 45 dwellings in high background radiation area in Takandeang, Indonesia with ambient dose equivalent rate ranging from 0.34 µSv•h-1 to 1.90 µSv•h-1 . The measurement was taken using passive radon and thoron discriminative detector and thoron progeny detector. This measurement was taken from November 2018 to October 2019, and within one month the detector would be replaced with a new detector. The concentrations of radon, thoron, and thoron progeny were calculated as 42–490 Bqm−3 , 20–618 Bqm−3 , and 4–40 Bqm−3 , respectively. The concentrations for outdoor were 49–435 Bqm−3 , 23–457 Bqm−3 , and 4–37 Bqm−3 , respectively, and the annual effective dose was 9.8–28.6 mSv•y-1 . Based on the result of Spearman’s correlations analysis between the indoor radon and thoron concentrations and between the indoor thoron progeny and thoron concentrations, we suggest that exposure to thoron cannot be predicted from exposure to radon, and the equilibrium equivalent thoron concentration has a large uncertainty when it is estimated from thoron concentration assuming a single thoron equilibrium factor.

4

Configuration of the parameters for scanner-based track detector evaluation system

Csordás Anita, Tóth-Bodrogi Edit, Kovács Tibor

Nukleonika

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2020

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Vol. 65, No. 2

133--137

EN

According to the new European Union Basic Safety Standards (EU-BSS), preparation of the National Radon Action Plan is obligatory for the Member States. One of the plan’s aims is to carry out an indoor radon survey to identify radon-prone areas. In the radon surveys, track detector methods are used. At the University of Pannonia (Veszprém, Hungary), a new scanner-based detector evaluation system has been developed. For the application of the new system, the selection of appropriate parameters is necessary. In this study, selection of the applied track detectors and setting of the etching conditions have been carried out. Two different types of allyl diglycol carbonate (ADC or CR-39) track detectors were investigated, taking into account the detector’s background and response during the exposure (determination of calibration factor). The Baryotrak’s background track density (0–1.5 tracksmm–2) was lower than that of the 0.8–4 tracksmm–2. The response of the Tastrak was higher, but the deviation of the calibration factor was much higher (1.2–5.3 × 10–3 tracksmm–2/(Bqdaym–3)) than in the case of the Baryotrak (1.4–2.8 × 10–3 tracksmm–2/(Bqdaym–3)). After the systematic review of the etching system, a new method was developed. For the determination of the optimal track diameter, the argon fluoride (ArF) laser was applied to create tracks with diameters in the range of 10–100 µ. The optimum track size was in the range of 40–60 µ. On this basis, new etching conditions were determined: 6.25 M NaOH solution, a temperature of 90 degree centigrade, and time period of 8 hours.

5

Outdoor radon concentration in China

Wu Q., Pan Z., Liu S., Wang C.

Nukleonika

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2016

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Vol. 61, No. 3

373--378

EN

A nationwide survey was conducted in 2014 to investigate environmental outdoor radon level in 33 provincial cities across China. The radon detector used was a passive-type solid-state nuclear track detector, CR-39. Measurements were conducted under the same condition following the quality control programme. Outdoor radon concentrations in China ranged from 3 to 30.0 Bq·m−3. The annual arithmetic and geometric mean radon concentration were 14 and 13.2 Bq·m−3, respectively. The radon concentrations in the locations near or along coastline were lower than the average value, while those located in the inland area were higher. As a whole, the result showed no big difference from the data measured during the period 1983–1998. It demonstrated that the outdoor radon concentration level in China has not been changing remarkably for 20 years.

6

Distribution of indoor radon concentrations between selected Hungarian thermal baths

Shahrokhi A., Nagy E., Csordás A., Somlai J., Kovács T.

Nukleonika

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2016

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Vol. 61, No. 3

333--336

EN

Owing to the high potential of radon to increase the risk of lung cancer, health organizations are enforced to update their regulations and recommendations regarding indoor radon levels each year. In this study, the indoor radon concentrations of three randomly selected thermal baths in Hungary using CR-39 and an AlphaGUARD radon monitor were measured with regard to the new updated standards of the European Basic Safety Standard (EU BSS, Council Directive 2013/59/Euratom, 2014). The annual average of indoor radon concentrations in Parad Medical Bath, Igal Health Spa and Eger Turkish Bath were measured as 159 ± 19, 176 ± 27 and 301 ± 30 Bq/m3, respectively. Indoor radon concentration in all measurement locations were determined to be below the reference level, with the exception of the main pool, small pool and sparkling bath areas in the Eger Turkish Bath that were measured as 403 ± 42, 315 ± 32 and 354 ± 36 Bq/m3, respectively. In light of the results, the estimated annual average radon concentration in the thermal baths was below the EU BSS reference level of 300 Bq/m3. Personal dosimetry is required to estimate the annual effective dose from inhaled radon by the workers at the Eger Turkish Bath. This procedure is required in order to justify the application of the mitigation process of decreasing working hours, improving the ventilation rate or increasing the number of classified employees in response to the official radiation surveillance programme.

7

Modification in surface properties of poly-allyl-diglycol-carbonate (CR-39) implanted by Au+ ions at different fluences

Sagheer R., Rafique M. S., Saleemi F., Arif S., Naab F., Toader O., Mahmood A., Rashid R., Hussain I.

Materials Science Poland

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2016

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Vol. 34, No. 2

468--478

EN

Ion implantation has a potential to modify the surface properties and to produce thin conductive layers in insulating polymers. For this purpose, poly-allyl-diglycol-carbonate (CR-39) was implanted by 400 keV Au+ ions with ion fluences ranging from 5 × 1013 ions/cm2 to 5 × 1015 ions/cm2. The chemical, morphological and optical properties of implanted CR-39 were analyzed using Raman, Fourier transform infrared (FT-IR) spectroscopy, atomic force microscopy (AFM) and UV-Vis spectroscopy. The electrical conductivity of implanted samples was determined through four-point probe technique. Raman spectroscopy revealed the formation of carbonaceous structures in the implanted layer of CR-39. From FT-IR spectroscopy analysis, changes in functional groups of CR-39 after ion implantation were observed. AFM studies revealed that morphology and surface roughness of implanted samples depend on the fluence of Au ions. The optical band gap of implanted samples decreased from 3.15 eV (for pristine) to 1.05 eV (for sample implanted at 5 × 1015 ions/cm2). The electrical conductivity was observed to increase with the ion fluence. It is suggested that due to an increase in ion fluence, the carbonaceous structures formed in the implanted region are responsible for the increase in electrical conductivity.

8

Thorium nuclear fuel - thoron aspect

Zagórski Z. P., Głuszewski W.

Nukleonika

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2010

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Vol. 55, No. 3

407-408

EN

The communication reports a serious complication connected with preparation, storage and transportation of fuel for thorium and uranium/thorium nuclear reactors. Whereas uranium fuel of any degree of enrichment is free from radium, which produces radon-222, thorium itself produces thoron (radon-220). Measurement of thoron by a routine ionization-chamber device around a small sample of 2 g thorium dioxide shows already the health endangerment situation. The presence of thoron is also confirmed by a typical solid state dosemeter (polymer CR-39), exposed to the air around ThO2 and etched afterwards with warm NaOH solution. The unavoidable presence of thoron can cause increase of price of production of nuclear fuel, demanding special approach to the method of manufacture.

9

D(3He,p)4He and D(d,p)3H fusion in a small plasma focus operated in a deuterium helium-3 gas mixture

Springham S., Sim T., Rawat T., Lee P., Patran A., Shutler P., Tan T., Lee S.

Nukleonika

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2006

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Vol. 51, nr 1

47-53

EN

Abstract A 3 kJ plasma focus was operated with a 3He-D2 gas mixture, with partial pressures in the ratio of 2:1, corresponding to an atomic number ratio of 1:1 for 3He and D atoms. The fusion reactions D(3He,p)4He and D(d,p)3H were measured simultaneously using CR-39 polymer nuclear track detectors placed inside a pinhole camera positioned on the forward plasma focus axis. A sandwich arrangement of two 1000 mi m thick CR-39 detectors enabled the simultaneous registration of two groups of protons with approximate energies of 16 MeV and 3 MeV arising from the D(3He,p)4He and D(d,p)3H reactions, respectively. Radial track density distributions were obtained from each CR-39 detector and per-shot average distributions were calculated for the two groups of protons. It is found that the D(3He,p)4He and D(d,p)3H proton yields are of similar magnitude. Comparing the experimental distributions with results from a Monte Carlo simulation, it was deduced that the D(3He,p)4He fusion is concentrated close to the plasma focus pinch column, while the D(d,p)3H fusion occurs relatively far from the pinch. The relative absence of D(d,p)3H fusion in the pinch is one significant reason for concluding that the D(3He,p)4He fusion occurring in the plasma focus pinch is not thermonuclear in origin. It is argued that the bulk of the D(3He,p)4He fusion is due to energetic 3He2+ ions incident on a deuterium target. Possible explanations for differing spatial distributions of D(3He,p)4He and D(d,p)3H fusion in the plasma focus are discussed.

10

CR-39 ssntd study of phosphate concretions of the Góry Bardzkie mountains (Sudetes)

Firlit G., Solecki M.

Chemia i Inżynieria Ekologiczna

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2005

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Vol. 12, nr 11

1201-1211

EN

Gamma-spectrometric mapping of the area with phosphate nodules occurrences of the Góry Bardzkie Mts have been performed. Maximum uranium concentration reached 22.1 ppm what is 5.4 standard deviations higher than the average background of the area (so-called standardized values). Potassium and thorium concentrations were definitely more uniform with standardized maximum values being 2.6 and 3.5, respectively. After calculation of terrestrial gamma dose emitted by 40K and uranium and thorium series radionuclides the maximum value was found to be as high as 175 nGy/h. CR-39 SSNTD study of uranium distribution within phosphate nodules bas been performed. Primary early-diagenetic lithological differentiation resulting in different organic matter and phosphate content of lower and upper part of the nodule bas been observed within petrographic thin section of the sample. Moreover, two generations of shear and tension veins bas been found. Spatial distribution of tracks combined with microscopic analysis of petrographic thin section indicates multistage history of diagenetic remobilizatrion of organic matter and uranium from the primary uranium enriched phosphate and organic matter layer.

PL

Przeprowadzone radiometryczne kartowanie obszaru występowania konkrecji fosforytowych z utworów sylurskich Gór Bardzkich za pomocą gamma-spektrometru GR-320 pozwoliło stwierdzić znaczące anomalie radiacyjne sięgające 175 nGy/h w miejscach, gdzie fosforytonośne utwory odsłaniają się na powierzchni. Badania pobranych próbek konkrecji za pomocą detektorów CR-39 SSNTD i mikroskopowej analizy szlifów petrograficznych pozwoliły stwierdzić pierwotne zróżnicowanie zawartości materii organicznej i fosforanów (te ostanie potwierdzone profilowaniem EDS w poprzek widocznych warstw). Zaobserwowano dwie generacje ścięciowych i tensyjnych żyłek. Przestrzenny rozkład śladów promieniowania alfa zarejestrowanych na kliszach CR-39 wskazuje, że istniejące pierwotne zróżnicowanie zawartości uranu zostało zmodyfikowane w trakcie formowania się pierwszej generacji żyłek - stref ścinania.