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1.
Summary In order to calibrate vials containing charcoal for measurement of radon, emanation sources of radon were produced in-house using 226Ra salts. Calibrated emanation standards containing solution of 226Ra(NO3)2 absorbed into inorganic compounds were prepared. The emanation coefficient of 222Rn for these standards vary from 0.23-0.25. The emanation sources were found to be suitable for calibrating radon monitors. 相似文献
2.
The analysis of 226Ra in natural waters can be tedious and time-consuming. For the determination and differentiation of activities of 226Ra and 222Rn in drinking water by γ-ray spectrometry a simple and fast method is presented. Activities of 226Ra > 0.5 Bq L−1 can be determined according to stabilization of the sample without further procedures. For a more sensitive detection sample
volumes of up to 5 litres are applicable by a rapid precipitation procedure without large expenditure. Further laborious enrichment
methods are not necessary. Thus, detection limits of 0.1 Bq L−1 can be obtained when using sample volumes of 5 litres. Therefore the method is suitable for the monitoring of radioactivity
in drinking water samples in accordance with the legal guidance of the European Union. 相似文献
3.
J. Justo H. Evangelista A. S. Paschoa 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(3):733-737
Summary The main shortcoming with the procedure to determine 226Ra in a gamma spectrum of an environmental sample by means of the 214Bi and 214Pb photopeaks is the likelihood of 222Rn leakage from the sample counting vial. An option to make such determination is to disregard the 226Ra gamma-contributions to the spectrum, other than 186.2 keV (3.5%), subtracting the 235U contribution to the 226Ra+235U peak at 186 keV. The use of this option to determine directly 226Ra activity concentrations in environmental samples and in NORM/TENORM matrices will be presented and discussed. 相似文献
4.
N. M. Antovic V. Popovic I. Antovic N. Svrkota P. Vukotic 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(1):81-88
A coincidence method for measuring 137Cs, 40K, 226Ra and 232Th decay products activity in soil, vegetation and fish samples, was applied to the six-crystal gamma-coincidence spectrometer
PRIPYAT-2M. In this way, some problems appeared in simultaneous measurement of 137Cs, 226Ra and 232Th by NaI(Tl) detectors and the PRIPYAT-2M spectrometer were solved. The obtained results were agreeable with the HPGe spectrometer
ones. 相似文献
5.
Tongke Zhao Lei Zhang Qiuju Guo Wenbin Dong 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(2):379-384
The activity concentrations of 218Po, 214Pb and 214Bi [i.e. C(218Po), C(214Pb), and C(214Bi)] and the calculated concentration ratios [i.e. 1:C(214Pb)/C(218Po):C(214Bi)/C(218Po)] are necessary for assessing radon and its progenies exposure. In this study, a measurement method of radon progenies concentrations with both high sensitivity and low uncertainty, was developed based on the Kerr method. The field measurement results of radon progeny concentrations and calculated concentration ratios in both typical indoor and outdoor environments in Beijing, China, were reported. The effects of air exchange rate on concentration ratios of radon progenies in indoor environments were discussed. 相似文献
6.
Tsuey-Lin Tsai Chun-Chih Lin Tsung-Yuan Wang Hwa-Jou Wei Lee-Chung Men 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):145-154
A rapid, accurate and less labor intensive approach to determining 226Ra in environmental samples was examined; this utilized quadrupole-based inductively coupled plasma mass spectrometry (ICP-QMS).
The procedure used chemical separation by ion exchange chromatography to remove most of the matrices after coprecipitation
with BaSO4. The average chemical recovery of the NIST SRM preparation method ranged from 60.5 to 85.9% using 133Ba as internal tracer by gamma counting. This technique was capable of completing a 226Ra measurement within 3 min. It did not require an in-growth period to allow radon and its progeny to achieve secular equilibrium
with the parent 226Ra as is needed for liquid scintillation analyzer (LSA). The method detection limits for the determination of 226Ra in geothermal water and sediment samples were 0.02 mBq L−1 (0.558 fg L−1) and 0.10 Bq kg−1 (2.79 fg g−1), respectively. The results obtained with various natural samples and the suitability of the method when applied to various
environmental matrices such as geothermal water and sediment are discussed. When ICP-QMS was compared to double-focusing magnetic
sector field inductively coupled plasma mass spectrometry (ICP-SFMS), good agreement was obtained with a correlation coefficient,
r
2 = 0.982. 相似文献
7.
Péter Völgyesi Zoltán Kis Zsuzsanna Szabó Csaba Szabó 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):375-383
The uranium isotopic abundance and the 238U–226Ra secular equilibrium were determined in nine Hungarian coal slag samples. The 226Ra activity concentration was measured based on the radon decay products and also the 226Ra peak at 186 keV. Secular equilibrium existed in eight samples, whereas one sample showed a slight disequilibrium. The direct and fast measurement using only the 186 keV peak was validated which can be used after measuring the uranium isotopic ratio and verifying the 238U–226Ra secular equilibrium. This method can be used to measure the 226Ra content of high number of samples from the same geochemical background. 相似文献
8.
M. Dowdall Ø. G. Selnaes J. P. Gwynn C. Davids 《Journal of Radioanalytical and Nuclear Chemistry》2004,261(3):513-521
The determination of 226Ra and 238U in environmental samples by gamma-spectrometry is most often carried out by hermetic sealing of the sample in a suitable
container, waiting until secular equilibrium that has been established in the 238U decay chain below 226Ra and counting of the high intensity emissions of 214Pb and 214Bi. The 186 keV multiplet can then be corrected to provide a measure of 235U and hence, 238U. The work presented in this paper involves a critical examination of the analysis of 238U and 226Ra in environmental materials without secular equilibrium established between 214Pb, 214Bi and their progenitor. Results indicate that the correction of the 186 keV doublet via 234Th determination is possible, even for low-level samples but careful consideration of both experimental conditions and the
composition of the sample matrix is required.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
Yong-Jae Kim Chang-Kyu Kim Cheol-Su Kim Ju-Yong Yun Byung-Hwan Rho 《Journal of Radioanalytical and Nuclear Chemistry》1999,240(2):613-618
A time-saving and accurate technique for determining226Ra in groundwater and soil was examined, using high-resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS). The
technique was applied to the determination of226Ra in groundwater and soil samples and compared with the conventional liquid scintillation counting method. This technique
was capable of completing226Ra counting within 3 minutes, without the in-growth period to allow radon and its progeny to achieve secular equilibrium with
the parent226Ra. The detection limits of HR-ICP-MS for226Ra in groundwater and soil were 0.19 mBq·1−1 and 0.75 Bq·kg−1, respectively, which were about 10 times lower than that of the liquid scintillation counter. The results obtained from HR-ICP-MS
in groundwater and soil were in accordance with those of LSC within a relative error of about 13%. 相似文献
10.
V. Goliáš D. Pittauerová R. Procházka Z. Třískala 《Journal of Radioanalytical and Nuclear Chemistry》2005,266(3):461-470
Summary The activities of218Po,214Po and211Bi were determined in samples obtained of soil/gas. Sampling work was taken in Jáchymov (Czech Republic) at the outcrop of
the Geister-vein,by electrostatic precipitation from filtered soil gas on stainless steel disks.The samples were measured
in a field laboratory using a semi-conductor alpha-spectrometer.The activities of218Po,214Po and211Bi were calculated.Samples taken from active dump material (near-by radon source) exhibited a high211Bi/214Po ratio, while those of the vein outcrop (a relatively deeper source) had a low ratio.A mathematical model was employed to
determine the radon age calculated from the actinon/radon input ratio.This varied in a range of 5.6 to -7.7 seconds.Negative
age values are probably caused by the preference for actinon, which rapidly comes into equilibrium with the source of this
gas. 相似文献
11.
<Superscript>226</Superscript>Ra and <Superscript>228</Superscript>Ra determination in environmental samples by alpha-particle spectrometry 总被引:1,自引:1,他引:0
J. L. Aguado J. P. Bolivar R. García-Tenorio 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(1):191-199
A complete methodology for 226Ra and 228Ra determination by alpha-particle spectrometry in environmental samples is being applied in our laboratory using 225Ra as an isotopic tracer. This methodology can be considered highly suitable for the determination of these nuclides when
very low absolute limits of detection need to be achieved. The 226Ra determination can be performed at any time after the isolation of the radium isotopes from the analyzed samples while the
228Ra determination needs to be carried out at least six months later through the measurement of one of its grand-daughters.
The method has been validated by its application to samples with known concentrations of these Ra nuclides, and by comparison
with other radiometric methods. 相似文献
12.
L. I. Tsikritzis 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(3):651-656
Summary The distribution and origin of 40K, 226Ra, 228Ra and 137Cs has been investigated in trees, mosses and lichens in the basin of the West Macedonia Lignite Centre. In tree leaves 137Cs is negligible, while the 226Ra and 228Ra concentrations are affected by the fly ash particles. Concerning 226Ra and 228Ra values of mosses and lichens, which are systematically larger than those of unpolluted areas, the application of chemometrics proved that they originate mainly from the lignite fly ash. 相似文献
13.
Zidan Mohamed M. Houmani Amran Ab. Majid Shahidan Radiman Zaharudin Ahmad 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):271-277
226Ra is a member of the 238U natural decay series and is one of the most important isotope to be determined among the naturally occurring nuclides in
environmental samples. In order to evaluate the radiation dose from 226Ra, it is important to know its mobility in different types of soils. The aim of the present study is to quantify the influence
of physico-chemical soil properties on 226Ra adsorption. The distribution coefficients (K
d-value) of 226Ra in Selangor soil series samples were measured in one core, at three depth levels to evaluate the adsorbability of 226Ra. The soil samples were spiked with 226Ra tracer and the activities of 226Ra in the separated phase from batch sorption test were measured by a low background but high efficiency well-type HPGe detector.
Several physico-chemical soil properties were also characterised for each soil samples. Pearson’s correlation and stepwise
multiple regression test were applied at the 0.05 level of significance throughout all analysis to determine the relationships
and influences between distribution coefficients (K
d-value) of 226Ra with physicochemical soil properties for the Selangor soil series. The observed K
d value was in the range of 50.55–172.28 mL g−1 (mean: 93.20 ± 46.99 mL g−1). The regression showed that the highest positive correlations were observed for organic matter (OM) and cation exchange
capacity (CEC) (r = 0.96**, 0.81**, respectively) with K
d-values. The results indicate that the stepwise multiple regression model incorporating the soil’s OM and CEC accounts for
98% of the variability in distribution coefficients of 226Ra. 相似文献
14.
Marine sediment cores were collected from two stations at East Malaysia coastal waters on June 2004. Activity concentrations
of 210Pb in sediment core were ranged from 11 Bqkg−1 to 84 Bqkg−1 dry wt. for SR 01 and 4 Bqkg−1 to 66 Bqkg−1 dry wt. for SB 03. Meanwhile, activity concentrations of 226Ra in sediment core were varied significantly depending on the sampling location of SR 01 and SB 03 with ranged 17–26 Bqkg−1 dry wt. and 8–11 Bqkg−1 dry wt., respectively. The activity ratios of 210Pb/226Ra were no significantly different at all sampling stations with an average of 1.78. Refer to the entire results; the activities
of 210Pb and 226Ra were higher at station SR 01 than station SB 03, but contrast with ratio of 210Pb/226Ra. The reasons of different 210Pb and 226Ra activity concentration and distribution of their ratios were strictly related to their half lives, environment origin,
potential sources and behavior. 相似文献
15.
Claudia Landstetter Christian Katzlberger 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(2):467-471
Screening measurements for 3H, 226Ra, 222Rn and 238U in ground water were performed within a ground- and drinking water project in Austria. The aim of this project is to get
an overview of the distribution of natural radionuclide activity concentration levels in ground water bodies. In some cases
this water is used for drinking water abstraction. In this paper methods and results of the screening measurements are presented.
Regions with high activity concentrations were identified and in these regions further investigation for 228Ra, 210Pb and 210Po will be conducted. 相似文献
16.
Vladimir S. Semenishchev Viktor P. Remez Anna V. Voronina 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(3):1311-1318
The Sorben-Tec system was tested for rapid dosimetric evaluation of 222Rn level in drinking water in domestic conditions using a dosimeter of beta radiometer as a measurement equipment. It was shown that the method is cheap, rapid and very simple, therefore it can be used by population for rapid radiation safety assessment of drinking water. The sorption-active Sorben-Tec system contains iron hexacyanoferrate allowing for separation of approximately 40% of both 214Pb and 214Bi, the short-lived decay products of 222Rn from 5 L water sample. It was assessed that the Sorben-Tec system provides detection limits of radon in 5 L water samples of 35–40 and 10 Bq L?1 for dosimetric and radiometric measurements respectively. The total time consumption of analysis does not exceed 1 h excluding the time for 214Pb and 214Bi ingrowth in the water sample (min. 3 h). Due to an insignificant sorption of radon, it is possible to reuse spent Sorben-Tec system again 3–4 h after previous analysis. 相似文献
17.
The activity concentrations of the Ra isotopes, 226Ra and 228Ra, as well as of 222Rn were measured in Austrian tap waters. Rn was extracted into a mineral oil cocktail not miscible with water and measured
by liquid scintillation counting using pulse-shape analysis for α/β-separation. Ra isotopes were co-precipitated with BaSO4 or concentrated by filtration through an element specific filter. EDTA solution was used to redissolve the precipitate as
well as to release the Ra from the filter. After mixing with a cocktail, the EDTA solution was measured by liquid scintillation
counting, too. From our results the effective ingestion doses for adults and 3 months old babies were calculated. 相似文献
18.
Zal U’yun Wan Mahmood Che Abd Rahim Mohamed Mei Wo Yii Zaharudin Ahmad Kamaruzzaman Ishak Abdul Kadir Ishak 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):107-113
Inventories and fluxes of 210Pb, 228Ra and 226Ra were determined in sediment cores collected at nine stations covering of the southern South China Sea and Malacca Straits
with the thickness of water column between 42 and 83 m depth. The inventories of 210Pb, 228Ra and 226Ra were calculated range from 0.15–2.55 Bq cm−2, 0.05–0.40 Bq cm−2 and 6.83–83.63 Bq cm−2, meanwhile the fluxes ranged from 0.005–0.079 Bq cm−2 yr−1, 0.009–0.048 Bq cm−2 yr−1 and 0.003–0.037 Bq cm−2 yr−1, respectively. The results show that the highest inventories and fluxes for 210Pb, 228Ra and 226Ra were found at station WC 01 and EC 05. Because there are additional sources of 210Pb, 228Ra and 226Ra, where water transport will brings more dissolved isotopes, influence of the transportation and deposition of suspended
particles, fast rate of regeneration and greater production of those radionuclides and others. 相似文献
19.
D. Larivière D. K. Brownell V. N. Epov R. J. Cornett R. D. Evans 《Journal of Radioanalytical and Nuclear Chemistry》2007,273(2):337-344
Three protocols (Method I: ion chromatography (IC) and extraction chromatography (EC), Method II: precipitation followed by
IC, and Method III: adsorption onto MnO2 followed by IC-EC) were investigated to determine their applicability for the separation and pre-concentration of 226Ra in sediments. 226Ra recoveries, measured using the isotope dilution method with 228Ra as yield tracer, and the removal of spectral and non-spectral interferences were evaluated. The formation of polyatomic
interferences at m/z = 226 from elements found in the matrix of sediments was also investigated to assess the level of separation required. Methods
I and III were found to be the most effective with respect to recoveries and interference removal. The efficiency of a rapid
microwave based protocol for the complete digestion of 1 g of sediment is also described. The method was tested and 226Ra concentrations in the millibecquerel range (fg) were determined in a standard reference material and sediment cores collected
from Lake Baikal. 相似文献
20.
P. Vesterbacka S. Klemola K. Salahel-Din M. Saman 《Journal of Radioanalytical and Nuclear Chemistry》2009,281(3):441-448
An intercomparison of the methodology (alpha, beta and gamma spectrometry) used for 238U, 235U and 210Pb determination was carried out based on 38 sediment samples. The activity range of the samples varied from 10–700 Bq/kg
for 210Pb, 1–35 Bq/kg for 235U and 10–800 Bq/kg for 238U. Results obtained using the three methods were not statistically different at high activity levels, but agreement between
the results decreased at lower sample activity levels. For 210Pb, the smallest difference was found between alpha and gamma spectrometry. A good correlation between results from alpha
and gamma spectrometry was observed over the whole activity range. In beta spectrometry, the results were slightly higher
than those obtained by alpha or gamma spectrometry due to the impurity of 228Ra. In 238U analysis, good correspondence was observed between 238U determined by gamma and alpha spectrometry, particularly at higher 238U activity concentrations over 100 Bq/kg. In 235U analysis, attention needs to be paid to interference from 226Ra and its reduction. 相似文献