共查询到20条相似文献,搜索用时 0 毫秒
1.
A method for210Po and210Pb determination in water samples is described. The nuclides are concentrated, in presence of added208Po and lead carrier, by evaporation. Then the polonium is plated electroless from the acidic solution on a copper planchet and measured by alpha spectrometry.210Pb separation from the other isotopes is based on the solutility of PbSO4 in citrate.210Pb content is determined by measuring the activity of its daughter210Bi. The critical steps in the isolation of lead have been examined and discussed. 相似文献
2.
Sherrod L. Maxwell Brian K. Culligan Jay B. Hutchison Robin C. Utsey Daniel R. McAlister 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(3):1977-1989
A new rapid method for the determination of 210Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that can be used for emergency response or routine water analyses. If a radiological dispersive device event or a radiological attack associated with drinking water supplies occurs, there will be an urgent need for rapid analyses of water samples, including drinking water, ground water and other water effluents. Current analytical methods for the assay of 210Po in water samples have typically involved spontaneous auto-deposition of 210Po onto silver or other metal disks followed by counting by alpha spectrometry. The auto-deposition times range from 90 min to 24 h or more, at times with yields that may be less than desirable. If sample interferences are present, decreased yields and degraded alpha spectrums can occur due to unpredictable thickening in the deposited layer. Separation methods have focused on the use of Sr Resin?, often in combination with 210Pb analysis. A new rapid method for 210Po in water samples has been developed at the SRNL that utilizes a rapid calcium phosphate co-precipitation method, separation using DGA Resin® (N,N,N′,N′ tetraoctyldiglycolamide extractant-coated resin, Eichrom Technologies or Triskem-International), followed by rapid microprecipitation of 210Po using bismuth phosphate for counting by alpha spectrometry. This new method can be performed quickly with excellent removal of interferences, high chemical yields and very good alpha peak resolution, eliminating any potential problems with the alpha source preparation for emergency or routine samples. A rapid sequential separation method to separate 210Po and actinide isotopes was also developed. This new approach, rapid separation with DGA resin plus microprecipitation for alpha source preparation, is a significant advance in radiochemistry for the rapid determination of 210Po. 相似文献
3.
Che Abd Rahim Mohamed Asnor Azrin Sabuti Nor Affizah Saili 《Journal of Radioanalytical and Nuclear Chemistry》2013,297(2):257-263
Biogenic burning as forest fire phenomena occurring from April to August each year in the Sumatra and Borneo islands are major sources of biogenic uranium–thorium decay series in marine systems. 30 samples were collected during the Ekspedisi Pelayaran Saintifik Perdana 2009 cruise (EPSP 2009 cruise) between 12th June and 1st August 2009 from the Straits of Malacca to the Sulu and Sulawesi Seas to study the effect of haze and the monsoon season on the deposition rate of 210Po and 210Pb in Malaysian waters. All samples were spiked with 1 ml of lead [Pb(NO3)2; 25 mg ml?1] and 0.05 ml of Polonium-209 tracer (26.08 dpm ml?1). 210Po activity was determined by auto plating onto silver foil and counting using an alpha spectrometry system (Canberra model Alpha Analyst with a silicon-surface barrier detector). Lead that was collected via electrodeposition, formed lead sulphate (PbSO4) precipitation. This precipitate was wrapped onto plastic discs and counted for 210Pb beta activity using a gross alpha–beta counting system (Tennelec model LB-5100 low background gas-flowing anti-coincidence alpha/beta counter) after 1 month to allow bismuth ingrowths. The range of 210Po activities varied between 51.08 ± 15.1 and 742.08 ± 220.34 Bq/kg, whereas the activity of 210Pb ranged from 31.10 ± 4.20 to 880.23 ± 123.86 Bq/kg and 210Po/210Pb ratio value varied between sampling stations from 0.19 to 13.77. The contents of 210Po were also statistically positively correlated with the amount of total suspended particulate especially those recorded during heavy haze period events. 相似文献
4.
K. Irlweck 《Journal of Radioanalytical and Nuclear Chemistry》2001,248(1):191-196
A new method for the radioanalytical determination of the 222Rn progenies 210Pb, 210Bi and 210Powill be presented, which has been improved for analyses of water samples fromdifferent regions in Austria. 1–2 liter samples were taken in polyethylenebottles prefilled with conc. HNO3 to obtain 0.2M acidic solutions,thus avoiding adsorption effects. After adding 1.6 mg of inactive lead carrier,the water sample was evaporated to dryness, converted to the chloride formand dissolved in 1M HCl. 相似文献
5.
The concentrations of210Po in samples from a coal gasifier were determined by -pulse height analysis following separations from complex organic matrices. Samples were dissolved using wet acid digestion and persulfate fusion techniques and then extracted with trilaurylamine. Polonium was auto-deposited onto silver disks using209Po as a tracer for yield determination. The precision of the experimental method, determined on coal, was ±6% at the 95% confidence level. Excellent agreement was attained with published data on an EPA coal sample.This work was sponsored by the Office of Health and Environment, Office of Environmental Programs, and the Office of Coal Processing, U.S. Department of Energy, under contract DE-AC05-840R21400, with Martin Marietta Energy Systems, Inc. 相似文献
6.
A method for the determination of uranium and 210Po in high salinity water samples has been elaborated. Both radionuclides are preconcentrated from 0.5 dm3 saline media by co-precipitation with hydrated manganese dioxide, followed by dissolution of the precipitate in 200 mL of 1 M HCl. Uranium isotopes 235U and 238U can be directly determined by ICP MS method with a detection limit of 0.01 ppb for 238U. Prior to a selective determination of 210Po, the majority of other naturally occurring α-emitting radionuclides (uranium, thorium and protactinium) can be stripped from this solution by their extraction with a 50% solution of HDEHP in toluene. Finally, 210Po is simply separated by direct transfer to an extractive scintillator containing 5% of trioctylphosphine oxide in Ultima Gold F cocktail and determined by an α/β separation liquid scintillation technique with detection limit below 0.1 mBq/dm3. 相似文献
7.
A. Kelecom R. C. S. Gouvea P. L. Santos 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(1):129-133
210Po and 210Pb concentrations have been determined in 58 cigar brands manufactured in 11 countries. Cuban and American cigars showed the lowest 210Po content. The mean levels of 210Po in Brazilian, European and Dominican cigars were almost identical and somewhat lower than the levels observed for cigars from other Latin American countries. Cuban, American and European cigars contained low levels of 210Pb. Cigars from the remaining countries contained twice as much 210Pb. The mean 210Po/210Pb ratio showed an excess of polonium. In the case of a one cigar-a-day smoker, the calculated annual absorbed dose due to 210Po is -16 mGy. 相似文献
8.
Nita Salina Abu Bakar Zal U’yun Wan Mahmood Ahmad Saat 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):315-323
In the present study, the depositions of 210Po were assessed in the surface soil and some mosses species found in the area around coal fired power plant using radiochemical deposition and alpha spectrometry counting system. The purposes of the study were to determine activity concentrations of 210Po in mosses and surface soil collected around coal-fired power plant in relation to trace the potential source of 210Po and to identify most suitable moss species as a bio-indicator for 210Po deposition. In this study, different species of mosses, Orthodontium imfractum, Campylopus serratus and Leucobryum aduncum were collected in May 2011 at the area around 15 km radius from Tanjung Bin coal-fired power plant located in Pontian, Johor. The 210Po activity concentrations in mosses and soil varied in the range 102 ± 4 to 174 ± 8 Bq/kg dry wt. and 37 ± 2 to 184 ± 8 Bq/kg dry wt., respectively. Corresponding highest activity concentration of 210Po observed in L. aduncum, therefore, this finding can be concluded this species was the most suitable as a bio-indicator for 210Po deposition. On the other hand, it is clear the accumulation of 210Po in mosses might be supplied from various sources of atmospheric deposition such as coal-fired power plant operation, industrial, plantation, agriculture and fertilizer activities, burned fuel fossil and forest; and other potential sources. Meanwhile, the main source of 210Po in surface soil is supplied from the in situ deposition of radon decay and its daughters in the soil itself. 相似文献
9.
J. A. Sanchez-Cabeza P. Masqué I. Ani-Ragolta 《Journal of Radioanalytical and Nuclear Chemistry》1998,227(1-2):19-22
A microwave acid digestion method prior to the determination of210Pb and210Po in sediments and soils is described. It involves an acid (HNO3, HCl, HF and H3BO3 mixture) digestion with microwave heating in closed vessels at high pressures. Analyses carried out for various reference
materials showed that the results were statistically equal to certified values and reproducibility was also assured. The advantage
of the microwave technique compared to the traditional leaching procedures is that the solid materials are completely dissolved
and, therefore, ca. 100% efficiency is achieved in the extraction of210Po and210Pb, even though a fraction is associated to the silica net. Moreover, time of analysis is drastically reduced, as are the
risks associated to vapour inhalation and material corrosion. 相似文献
10.
A quantitative separation procedure for210Po in lead has been developed by cupferron and dithizone extraction. The210Po activity is plated on a silver foil for counting with a ZnS(Ag) scintillator, or by α-spectrometry with a surface barrier semiconductor. Different lead samples were analyzed ranging from very old lead with a negligible210Po content to recently manufactured lead samples showing up to 9100 disintegrations per hour and per gram of lead. The reproducibility and the accuracy of the analyses are satisfactory. 相似文献
11.
Studies have been carried out on the solubility of Pu(III) oxalate by precipitation of Pu(III) oxalate from varying concentrations of HNO3/HCl (0.5–2.0M) solutions and also by equilibrating freshly prepared Pu(III) oxalate with solutions containing varying concentrations of HNO3/HCl, oxalic acid and ascorbic acid. Pu(III) solutions in HNO3 and HCl media were prepared by reduction of Pu(IV) with ascorbic acid. 0.01–0.10M ascorbic acid concentration in the aqueous solution was maintained as holding reductant. The solubility of Pu(III) oxalate was found to be a minimum in 0.5M–1M HNO3/HCl solutions containing 0.05M ascorbic acid and 0.2M excess oxalic acid in the supernatant. 相似文献
12.
A. Aarkrog 《Journal of Radioanalytical and Nuclear Chemistry》2001,248(3):587-593
A rapid method for the separation of 210 Po from 210 Pb was developed utilizing extraction of triisooctylamine (TIOA)/xylenein HCl+H2O2 medium. Polonium in the form of PoCl 6
2– was extracted into TIOA phase and 210Pb remains in the aqueous phase. Lead-210 was determined by -countingof its granddaughter, 210 Po ingrown from 210 Pb forsome period of time. Distribution of 210 Po and 210Pb in TIOA and aqueous phases was investigated in various concentrations ofHCl media. Hydrogen peroxide was used to further decompose organic matterand to remove sulfur to prevent its deposition on the silver disc. The improvedprocedure resulted in a good chemical yield (80–95%) and a good á-resolution. 相似文献
13.
Pulhani Vandana Reddy Priyanka J. Chaudhury Moushumi Tripathi R. M. 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(1):29-36
Journal of Radioanalytical and Nuclear Chemistry - A methodology for separation and purification of 210Po from uranium, thorium and daughters has been studied. Solvent extraction coupled with... 相似文献
14.
M. Yamamoto Y. Yamauchi H. Kawamura K. Komura K. Ueno 《Journal of Radioanalytical and Nuclear Chemistry》1992,163(1):37-45
210Pb and210Po in human hair have been measured to serve as an aid in order to estimate the dietary intake and body burden of these radionuclides of Japanese. The210Po concentrations found in 83 hair samples were ranging from 4.0 to 59.3 mBq/g with a mean (median) value of 18.2±12.2 (14.9) mBq/g as compared to the210Pb concentrations from 0.7 to 6.5 mBq/g with a mean (median) value of 2.3±1.1 (2.0) mBq/g. The210Po/210Pb activity ratios (mean: 8.7±5.1, median: 7.1) were surprisingly higher compared with the available literature value of about 2. The high concentration of210Po in human hair of Japanese may be due to the ingestion of animal protein mainly in the form of seafood. 相似文献
15.
A method for determining210Po in marine samples by wet dissolution, deposition onto silver disc and counting by -spectrometry is described. Recovery of polonium was obtained with208Po tracer.210Po levels in fish from the Brazilian coast and sediments from Antarctic region were determined. Levels in fish ranged from 0.5 to 5.3 Bq·kg–1 wet and for sediments, mean values of 10 mBq·kg–1 were obtained. 相似文献
16.
Tee Lee Theng Zaharuddin Ahmad Che Abd. Rahim Mohamed 《Journal of Radioanalytical and Nuclear Chemistry》2003,256(1):115-120
Sediment cores were obtained from Teluk Brunei, Sipitang, Teluk Kimanis, Kota Kinabalu and Kuala Penyu at the coastal water of Sabah and analyzed for 210Pb and 210Po to estimate the sedimentation rates. The calculated sedimentation rates of 210Pb and 210Po varied from 0.003 to 0.049 cm/y and 0.74 to 8.77 cm/y, respectively. The highest sedimentation rates were determined for 210Pb and 210Po at stations located at Sipitang (mean: 0.027 cm/y) and Teluk Kimanis (mean: 5.53 cm/y), respectively. The sedimentation rate estimated for 210Pb is not fully reliable because the activity of 226Ra was higher than that of 210Pb and bioturbation was active at the sampling stations. 相似文献
17.
Y. Takizawa L. Zhao M. Yamamoto T. Abe K. Ueno 《Journal of Radioanalytical and Nuclear Chemistry》1990,138(1):145-152
To determine the levels of210Pb and210Po in human tissues of people in Japan, various tissue samples were obtained at autopsy from the cadavers of 22 oncologic cases, mainly in Niigata Prefecture in northern Japan, from 1986 to 1988.Wet ashing, followed by electrochemical deposition and alpha spectrometry were used to separate and determine the210Pb and210Po present. Among the tissues analyzed, the highest concentrations of210Pb and210Po were observed in bone (sternum), liver, and kidneys. The total body burden of210Pb and210Po was found to be approximately 427 pCi and 514 pCi, respectively. This estimated210Po value did not differ significantly from values found in populations in the U.S.A. and European countries. 相似文献
18.
Joost R. W. Woittiez Joyce E. Sloof Koos J. Kroon 《Analytical and bioanalytical chemistry》1995,352(1-2):214-218
A quality control programme is presented for the determination of 210Po in samples from the phosphate ore-processing industry. Accuracy and precision of selected steps of the analytical procedure are quantified and the change in these parameters is monitored by analysis of hundreds of reference samples during the last two years. 相似文献
19.
I. L. Cunha L. Bueno D. I. T. Fávaro V. A. Maihara S. Cozzollino 《Journal of Radioanalytical and Nuclear Chemistry》2001,247(2):447-450
Radiochemical procedures for the analysis of 210 Pb and 210 Po in foods and diets are presented. Because of the low beta energy of 210 Pb, its analysis was based on a separation of the daughter radionuclide 210 Bi by precipitation of lead sulphate, 210 Bi ingrowing and beta counting of this nuclide. 210 Po analysis was based on wet dissolution of the sample, deposition onto silver disc and counting by alpha-spectrometry. Levels of these radionuclides in individual items and diets of selected university students were determined in order to evaluate the intakes of 210 Pb and 210 Po as well as the dose due to ingestion of foods and diets in São Paulo city. 相似文献
20.
Journal of Radioanalytical and Nuclear Chemistry - Among various naturally grown-medicinal herbs investigated, the estimated natural radioactivity content of 210Po is found to be the highest in the... 相似文献