共查询到20条相似文献,搜索用时 15 毫秒
1.
A. N. Berlizov A. D. Sajeniouk V. V. Tryshyn 《Journal of Radioanalytical and Nuclear Chemistry》2005,263(2):307-310
Summary A technique is proposed for the determination of the concentration of strontium, plutonium and americium radioactive isotopes in single samples from various environmental matrices. The technique is based on the consecutive determination of strontium by extraction, and plutonium and americium isotopes by ion-exchange chromatography. It allows reliable results to be obtained at significant reduction of the sample preparation and solution transfer times. 相似文献
2.
A. Tovedal U. Nygren H. Ramebäck 《Journal of Radioanalytical and Nuclear Chemistry》2008,276(2):357-362
In radiological emergency, rapid determination of radiostrontium will be necessary. The required quantification levels will
be relatively high which offers smaller sample sizes and shorter ingrowth and counting times. In this paper a rapid method
for the determination of 90Sr in fresh milk in emergency preparedness is presented. The method is based on microwave digestion, chemical separation of
Sr, ingrowth of 90Y and Cherenkov measurements. In order to minimize the total analysis time, a mathematical model was developed. For a given
number of samples the model minimizes the analysis time by optimizing the ingrowth and counting time in order to reach a detection
limit fit-for-purpose. 相似文献
3.
T. Jabbar K. Khan M. S. Subhani P. Akhter 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(2):377-384
Assessment of 90Sr is of great interest owing to the fact that this artificially produced radionuclide has high radiological importance because
of its high fission yield, chemical similarity to calcium and its relatively long biological and physical half-life. To assess
the likely hazard to population, low level 90Sr in environmental samples is determined using pre-equilibrated tri-butyl phosphate (TBP) solvent and extraction-liquid scintillation
procedure. 90Y is selectively extracted from nitric acid solution into TBP solvent and stripped into aqueous phase as oxalate. The activity
is finally measured by low level liquid scintillation counter using Cerenkov radiation. The specific activity is found only
in three vegetation samples with average value of 2.86±1.7 Bq·kg−1 of dry weight. In all other samples analyzed, the activity is below the detectable limit, i.e., 0.03 Bq. Results obtained
are comparable with other areas of Pakistan. The chemical recovery of 90Y varies from 75 to 90% for soil, vegetation and water. The present study provides a general background of the detectable
radionuclide for the surveyed area that will be helpful in any radiological emergency. 相似文献
4.
Sultan Şahin Fatih Külahcı Mahmut Doğru 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(2):313-318
In this study, 90Sr (540 keVβ −), 129I (150 keVβ −) and the gross beta radioactivity concentrations were determined for the samples of tea as the most leading consumed hot
drink in the markets (processed and packaged for sale) in our country. Furthermore, the obtained data were statistically analyzed.
For determination of 129I (150 keVβ−), 90Sr (540 keVβ−) and gross radioactivity concentrations in tea samples, a sensor system consisting of scintillation detector with BP4 probe
sensitive to beta radiation and a radiation meter (ST7) configurable for windows at desired power was used. 相似文献
5.
Zack Varve Edward P. C. Lai Chunsheng Li Baki B. Sadi Gary H. Kramer 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1411-1415
A rapid bioassay for 90Sr was developed involving preconcentration of 90Sr/90Y from human urine samples with a cation exchange polymer (poly–acrylamido–methyl–propanesulfonic acid) coated onto magnetic
nanoparticles, followed by selective elution of 90Sr (over 90Y) with phosphate for determination by liquid scintillation analysis. The minimum detectable activity for this method (4.9 ± 0.5 Bq/L)
is lower than the required sensitivity of 19 Bq/L for 90Sr in human urine samples, as defined in the requirements for radiation emergency bioassay techniques for the public and first
responders based on the dose threshold for possible medical attention recommended by the International Commission on Radiological
Protection. The relative bias was 9.2%, the relative precision was 3.2%, and the linear dynamic range covered 12–600 Bq/L.
This simple and rapid bioassay method is found to be in compliance with the HPS ANSI N13.30 performance criteria for radiobioassay. 相似文献
6.
The aim of this paper was to determine the extent of contamination by anthropogeneous radionuclides 137Cs and 90Sr in the bottom sediments from the Barents Sea based on the radioactive activity of the samples taken up in August 1991,
among others, from the area close to New Land Island and Francis Joseph Archipelago. The results are based on the phenomenon
of vertical migration, in the bottom sediments which is of significant importance from the natural environment point of view. 相似文献
7.
Judit Groska Zsuzsa Molnár Edit Bokori Nóra Vajda 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):707-715
The presence of 89Sr and 90Sr in the biosphere constitutes a biological hazard. There are several analytical methods for the determination of 89Sr and 90Sr. Three analytical methods of various application fields using selective Sr resin for Sr separation and DGA resin for Y
separation and measuring techniques, i.e. liquid scintillation spectrometry and Cerenkov counting are discussed in the paper.
The calculation techniques are compared in the aspects such as trueness and accuracy of the results and the limit of detection.
Uncertainties and detection limits are calculated using the spreadsheet method. 相似文献
8.
Matthias J. Brunnermeier Stefanie A. K. Schmied Robert Schupfner 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1285-1290
The period of date of death of an elephant can be assessed by analyzing four different radionuclides, 14C, 90Sr, 228Th and 232Th in its ivory. These nuclides are supposed to have variing concentrations at different parts of a tusk. The reason is the
procedure of growth which takes place at the butt-site of a tusk. Therefore the site of sampling could have a big influence
on the assessed date of death. However, to find out if the position of sampling is important a complete tusk was analyzed
regarding the distribution of these nuclides. Results show that the concentration activity of 14C and 228Th varies in different parts of a tusk. The activity concentration of 90Sr is very similar in all analyzed parts. The conclusion is that sampling at the butt of a tusk is recommended for age assessment. 相似文献
9.
A. D. Sajeniouk 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(2):337-342
10.
Annika Tovedal Ulrika Nygren Petra Lagerkvist Anna Vesterlund Henrik Ramebäck 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(2):461-466
In this work a method for the determination of both 89Sr and 90Sr is presented. The method can potentially be used in radiological emergency and deliver results shortly after an incident.
The method development was based on theoretical calculations of potential interferences from other fission products and how
these could be discriminated when applying different chemical separation schemes. Validation was done on reactor coolant water
containing short-lived fission products, and on a reference material. The results indicate that correct results of 89Sr and 90Sr can be obtained 4 and 9 days, respectively, after an incident. 相似文献
11.
L. Popov G. Mihailova I. Naidenov 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):223-237
The origins of different artificial radionuclides found in soils from Northern and Southern Bulgaria was determined by measurements
of their actual concentrations and respective ratios. On the basis of the measured mobility and concentrations of the investigated
radionuclides in soils, it was estimated that after the Chernobyl accident the mean depositions of fresh 137Cs were 3.0 ± 2.5 kBq/m2 for Northern Bulgaria and 15 ± 7 kBq/m2 for Southern Bulgaria. As a result of global fallout following atmospheric nuclear weapon tests in the 1950s, mean depositions
(corrected to 1965) were calculated for Northern and Southern Bulgaria as follows: for 90Sr—1.0 ± 0.5 and 2.3 ± 1.3 kBq/m2, 238Pu—1.3 ± 0.8 and 2.8 ± 1.6 Bq/m2, 239+240Pu—15 ± 14 and 47 ± 38 Bq/m2, and 241Pu—520 ± 200 and 760 ± 260 Bq/m2. 相似文献
12.
A. H. Al-Rayyes M. Al-Oudat A. Al-Hamwi H. Mukhallalati 《Journal of Radioanalytical and Nuclear Chemistry》2007,274(1):139-143
The experiment aimed to evaluate the vertical migration of 134Cs, 90Sr and 238Pu in the main types of Syrian soils; entisol, inceptisol, alluvial (rock outcrops) and gypsiferous soils, using soil columns
through which the aqueous solution of the radionuclides percolated. The results show that the vertical migration of the studied
radionuclides through the soil profile depend on the radionuclide and the soil type. More than 97% of 134Cs and 238Pu concentrated in the upper 2 cm of the entisol, inceptisol, and alluvial soils, whereas only 46.2% to 68.6% of the 90Sr was retained in the upper 2 cm of these soils. The vertical migration of the studied radionuclides in the gypsiferous soil
was different from the other soils. The distribution of the radionuclides in the gypsiferous soil was irregular through the
soil profile and reached the deeper layer of the soil. This may be due to its physical characteristics; poor structure stability,
high permeability and low retention capacity. 相似文献
13.
Y. Spasova U. Wätjen T. Altzitzoglou 《Journal of Radioanalytical and Nuclear Chemistry》2008,277(1):211-215
Recently, the Institute for Reference Materials and Measurements (IRMM) has assumed responsibility for organizing regular
measurement comparisons among those laboratories which provide radioactivity monitoring data from their country to authorities
of the European Commission (EC) under various EC legislation articles. The most recent exercise under this International Comparison
Scheme for Radioactivity Environmental Monitoring (ICS-REM) in measuring the 137Cs, 40K and the 90Sr activity concentration in milk powder is presented here. The complete cycle of the comparison is described, including the
establishment of reference values traceable to SI units, the demonstration of the homogeneity of the distributed samples,
the treatment and measurement of samples in the participating laboratories, and the evaluation of the results. 相似文献
14.
Summary The dispersion of radioactive substances in the environment following nuclear weapon tests in atmosphere since 1954 and accidents to nuclear plants, like that in Chernobyl in 1986, have allowed us to study the migration processes of some radionuclides in complex ecosystems such as lakes are. In the present paper the behavior of 137Cs and 90Sr in different compartments of the Monterosi Lake (central Italy) was assessed. The 137Cs concentration was measured in lake water as well as sediment, stream water, aquatic plant and fish samples. 90Sr concentration in water and sediments was also determined. A total inventory of 4206±76 Bq . m-2 and 958±79 Bq . m-2 (on 27/6/01) has been found for 137Cs and 90Sr, respectively. The experimental data presented here allow to calibrate theoretical models predicting the temporal trend of radionuclide concentration in similar ecosystems. Moreover, information on cesium and strontium migration processes can be extended to other pollutants having similar environmental behavior. 相似文献
15.
Rajesh Chakraborty Sanjoy Dhara Sukalyan Basu Pabitra Chattopadhyay 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(1):55-59
An inorganic ion exchanger, quinolinephosphomolybdate has been synthesized and characterized by elemental analysis, infrared
(IR) and X-ray diffraction (XRD) spectroscopy. This compound is highly stable toward thermal, chemical and radiation dose.
This has been employed in the separation of carrier-free 90Y from its parent 90Sr from an equilibrium mixture. The absorbed daughter was recovered by using 0.0284 mol L−1 ascorbic acid solutions at pH 5.0 as eluting agent. 相似文献
16.
Chang Heon Lee Myung Ho Lee Sun Ho Han Yeoung-Keong Ha Kyuseok-Song 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):319-325
A simple and rapid separation procedure was systemized for the determination of 99Tc, 90Sr, 94Nb, 55Fe and 59,63Ni in low and intermediate level radioactive wastes. The integrated procedure involves precipitation, anion exchange and extraction
chromatography for the separation and purification of individual radionuclide from sample matrix elements and from other radionuclides.
After separating Re (as a surrogate of 99Tc) on an anion change resin column, Sr, Nb, Fe and Ni were sequentially separated as follows; Sr was separated as Sr (Ca-oxalate)
co-precipitates from Nb, Fe and Ni followed by purification using Sr-Spec extraction chromatographic resin. Nb was separated
from Fe and Ni by anion exchange chromatography. Fe was separated from Ni by anion exchange chromatography. Ni was separated
as Ni-dimethylglyoxime precipitates after the removal of 134,137Cs and 110mAg by Cs-phosphotungstate and AgCl precipitation, respectively. Finally, the radionuclide sources were prepared by precipitation
for their radioactivity measurements. The reliability of the procedure was evaluated by measuring the recovery of chemical
carriers added to a synthetic radioactive waste solution. 相似文献
17.
The aim of this article was to present the studies of radiological level of some commercial dairy products in Mazovian, Kuyavian—Pomeranian
and Lublin regions. They were carried out for 27 commercial dairy products such as two specimens of lean cottage cheese, three
specimens of cottage cheese containing a limited percentage of fat, three specimens of fat cottage cheese, three specimens
of milk containing 3.2% of fat, three specimens of milk containing 2.0% of fat, two specimens of sour cream containing 12%
of fat, three specimens of sour cream containing 18% of fat, one specimen of 30% whipping cream, two specimens of homogenized
(strawberry and vanilla) cheese, three specimens of hard rennet cheese, one specimen of powdered milk, one specimen of goat
milk. For the given commercial dairy products there were calculated effective doses (μSv) obtained after consumption of 1 kg
contaminated product for different age groups. 相似文献
18.
L. Lazare C. Crestey C. Bleistein 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(2):633-638
The present procedure for analysing 90Sr combines the use of a non radioactive carrier with high pressure ion chromatography separation, conductivity detection
of the carrier and optimized external counting by liquid scintillation. This improvement with respect to traditional methods
led to a more rapid and efficient purification stage. The present work proves that activities of 90Sr as low as 3 Bq/L can be measured in highly contaminated pressurized water reactor primary coolant matrix without any observed
radiochemical interference. The approach shows promise for the analysis of other emitters of low energy radiation, or isotopes
subject to high background or matrix effects in a PWR primary coolant. 相似文献
19.
S. Osaki S. Sugihara Y. Maeda T. Osaki 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(1):135-140
Depth distribution of atmospheric 210Pb and 7Be and 90Sr and 137Cs fission products was measured in two types of aeolian soils (desert dust and volcanic ash), irrigated paddy soil and strongly
acidic soil. The depth dependence of 210Pb, 7Be and 137Cs show that these radionuclides have been diffused as solid soil particles in surface soil layers. In aeolian soil layers,
about 50% of 90Sr were diffused in surface soil layer and the remaining 50% had penetrated to deeper layers. The half of the fission particles
containing 90Sr were shown to have decomposed over the past 35 years. 相似文献
20.
Željko Grahek Astrid Gojmerac Ivšić Nikolina Krljan Marijana Nodilo 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):437-449
This paper describes the procedures of isolating strontium from wine and soil samples which enable creating of procedure for
rapid determination of 90Sr. The method of determination of 90Sr includes binding of Sr on the cationic exchanger IR-120 from the sample and simultaneous elution from the cation column
and binding on the Sr column, separation of Sr on Sr resin with HNO3 even in presence of alcohols and subsequent Cherenkov counting. Sr can be efficiently bind on Sr resin and separated from
the other elements with lower acid concentrations in the presence of a low portion of alcohol, or even from a wine sample
without the loss of Sr resin capacity. The binding strength of Sr on Sr resin decreases with the rising of HNO3 concentration (1–5 M) in the presence of 13% of ethanol or methanol, and with the rising of the alcohol portion in constant
concentration of HNO3. Application of cation exchanger for Sr binding in phase of sample preparation decreases Sr column loading and improve Sr
recovery. The method allows the determination of 90Sr activities in wine and soil sample lower than 10 mBq in reasonable time. 相似文献