共查询到20条相似文献,搜索用时 31 毫秒
1.
S. Ravi S. Ravi A. K. Deepa A. K. Deepa S. Susheela S. Susheela P. V. Achuthan P. V. Achuthan S. Anil Kumar U. Jambunathan 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(1):79-82
Summary A method has been developed for the estimation of 90Sr in reprocessed uranium oxide samples obtained from the Purex processing of natural uranium spent fuel discharged from the
research reactor. The method employs a combination of precipitation and solvent extraction procedure to eliminate other beta-impurities
prior to resorting to the estimation of 90Sr by beta-counting. 106Ru was eliminated by volatalizing with perchloric acid, uranium was removed by carrier precipitation with strontium as sulphate.
The sulphate precipitate was converted to carbonate and dissolved in nitric acid. 234Th and 234Pa were eliminated by synergistic solvent extraction using tri-n-butyl phosphate and thenoyl trifluoroacetone extractant mixture
in xylene. An iron scavenging step was included to remove any residual impurities. Finally, strontium is precipitated as SrC2O4. H2O. The separated 90Sr activity was followed to check the equilibrium growth of 90Y. 相似文献
2.
I. I. Dovhyi D. A. Kremenchutskii V. Yu. Proskurnin O. N. Kozlovskaya 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(3):1643-1648
90Y was separated from 90Sr using an extraction chromatographic resin consisting of 4, 4′(5′)-bis-t-butylcyclohexano-18-crown-6 (DtBuCH18C6), 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl) amide (C2mimNTf2), and a polymer (Amberlite XAD-7). Ionic liquid was introduced into the column to improve the separation efficiency. The column showed an excellent performance for the separation of Y from Sr. After the separation, the ratio of 90Sr/90Y was <2.0 × 10?5; the column was recycled for >18 times. This study provides preliminary results on columns to produce 90Y with a high purity in radiopharmaceuticals. 相似文献
3.
Veronika Drábová Jana Strišovská Lívia Dvorská Jozef Kuruc 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1141-1145
Two separation techniques for strontium determination using AnaLig® Sr01 molecular recognition technology and extraction chromatography Sr® resin were tested. The methods performance was investigated by analysis of NPL (High Alpha–Beta 2003) intercomparison sample. The results obtained for both procedures were compared in terms of activities and recoveries. Data analysis proved a good agreement with the reference values. The AnaLig® Sr01 separation method for 90Sr determination was successfully validated with the same performance as the Sr® resin method. 相似文献
4.
B. K. Kasenov E. S. Mustafin S. N. Merkur’eva M. A. Akubaeva Sh. B. Kasenova S. T. Edil’baeva R. Sh. Erkasov 《Russian Journal of Inorganic Chemistry》2007,52(10):1514-1515
La2M 3 II Mn4O12 (M = Mg, Ca, Sr, or Ba) manganites have been synthesized by ceramic technology from lanthanum oxide, manganese(III) oxide, and magnesium, calcium, strontium, or barium carbonate. X-ray powder diffraction shows that these compounds crystallize in cubic perovskite space group Pm3m. 相似文献
5.
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
6.
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
7.
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
8.
Claudia Landstetter Wolfgang Ringer Arno Achatz Christian Katzlberger 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(2):435-439
90Sr was measured in environmental samples in Upper Austria in the year 2005. After the nuclear weapon tests the average deposition of 90Sr in Austria amounted to 3.3 kBq/m². In 1986 the average deposition was 0.9 kBq/m² [1]. To assess the actual condition in soil, grass and cereals 90Sr was measured in these samples. For all samples oxalate precipitation was conducted and strontium specific columns (Eichrom Industries, Inc.) were used. The calcium concentration in these samples was determined to estimate the amount of resin needed for the preparation. For grass and cereal samples columns were packed with the 100–150 μm resin to gain a lower limit of detection LLD below 2 and below 0.1 Bq/kgdry matter respectively. The prepacked 2 mL columns with particle size 100–150 μm were used for soil (LLD below 2 Bq/kgdry matter). After digestion of soil samples, hydroxide precipitation was used as an additional separation step. The 90Sr was measured by liquid scintillation counting. For quality control reasons, first the initial strontium concentration in the sample was determined then a strontium carrier solution was added and after the separation steps the chemical recovery was determined by ICP-MS. Thus, no radioactive tracer and just a small amount of the measuring solution were needed. The results are presented and discussed. These results will be used as reference for further 90Sr analyses which will be conducted in a 5 year period to detect any radiological impact of the nuclear power plant Temelin on the environment of Austria. 相似文献
9.
Ranjeet Kumar J. R. Yadav D. D. Rao 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):451-454
Bioassay technique is used for the estimation of actinides present in the body based on their excretion rate through body
fluids. For occupational radiation workers urine assay is the preferred method for monitoring of chronic internal exposure.
Determination of low concentrations of actinides such as plutonium, americium and uranium at low level of mBq in urine by
alpha spectrometry requires pre-concentration of large volumes of urine. This article deals with standardization of analytical
method for the determination of 241Am isotope in urine samples using Extraction Chromatography (EC) and 243Am tracer for radiochemical recovery. The method involves oxidation of urine followed by co-precipitation of americium along
with calcium phosphate. This precipitate after treatment is further subjected to calcium oxalate co-precipitation. Separation
of Am was carried out by EC column prepared by PC88-A (2-ethyl hexyl phosphonic acid 2-ethyl hexyl monoester) adsorbed on
microporous resin XAD-7 (PC88A-XAD7). Am-fraction was electro-deposited and activity estimated using tracer recovery by alpha
spectrometer. Ten routine urine samples of radiation workers were analyzed and consistent radiochemical recovery was obtained
in the range 44–60% with a mean and standard deviation of 51 and 4.7% respectively. 相似文献
10.
M. Tabasi M. Ghannadi-Maragheh l M. Shamsaii A. R. Khanchi 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(3):679-686
Summary Separation and purification of 133Xe from acidic solution containing uranium, 99Mo and 131I has been developed. In the first step of this work, uranium pellets were dissolved under pressure (8-15 bar) in 8M nitric acid solution. Then133 Xe and other gases were conducted to activated charcoal cold trap. Final purification of 133Xe from impurities such as NOx, radioiodine and krypton was performed by passing through a molecular sieve preparative chromatographic column using helium as mobile phase. The final recovery of 133Xe from the separation-purification process was higher than 98%. Adsorption-desorption behavior of radioxenon on the charcoal and molecular sieves have also been studied and discussed. 相似文献
11.
H. Michel M. Schertz G. Barci-Funel G. Ardisson 《Journal of Radioanalytical and Nuclear Chemistry》2003,258(2):209-213
A radiochemical procedure to extract plutonium, americium and strontium from soils is presented. Strontium was separated from americium and plutonium fraction at the beginning of the method to increase the Sr recovery. The studied soils coming from an Alpine wetland site contain a big amount of iron which was eliminated by an oxalate precipitation before the column step. The hydroxide precipitation should be made by adding iron of known quantity to avoid interference. The procedure was validated by reference soils from IAEA. Plutonium-238, 239, 240, 241Am, 90Sr and 137Cs activities are given and some isotopic ratios are calculated in order to know the origin of the radionuclides. 相似文献
12.
Chang Heon Lee Moo Yul Suh Kwang Yong Jee Won Ho Kim 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(1):187-194
A sequential separation procedure has been developed for the determination of 99Tc, 94Nb, 55Fe, 90Sr and 59/63Ni in various radioactive wastes generated from nuclear power plants. Ion exchange and extraction chromatography were adopted
for individual separation of the radionuclides. Precipitation was supplementarily utilized for both purification of the individual
radionuclides and preparation of the radionuclide sources for use in a radioactivity measurement. The chromatographic separation
behavior of the radionuclides both from the sample matrix metals and from one another was investigated using stable metals,
Re (as a surrogate of 99Tc), Nb, Fe, Sr and Ni. The validity of the procedure for reliability and applicability was evaluated by measuring the recovery
of the metal carriers added to synthetic radioactive waste solutions. The recoveries by the chromatographic separation were
in the range of 84.8 to 102.2% with 2s of less than 8.6%, the recoveries by the precipitation being in the range of 84.3 to 97.3% with 2s of less than 10.9%. 相似文献
13.
Prem Singh Dhami C. Janardanan Poonam Jagasia S. Pahan S. C. Tripathi P. M. Gandhi P. K. Wattal 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(3):1341-1347
This paper describes a method for the separation and purification of 90Sr from PUREX–HLLW employing solvent extraction and precipitation techniques. 30 % TBP in n-dodecane was used for the removal of residual uranium, plutonium and neptunium from HLLW. Trivalent actinides and lanthanides were subsequently removed using N,N,N’,N’-tetra(2-ethylhexyl) diglycolamide (TEHDGA, 0.20 M in 30 % isodecyl alcohol and n-dodecane). 90Sr was selectively extracted from actinides and lanthanides depleted HLLW using 0.3 M TEHDGA in 5 % isodecyl alcohol and dodecane. Loaded strontium was stripped using 0.01 M HNO3 and further purified by radiochemical precipitation technique after adding Fe and natural strontium as carriers. Based on the experimental results, a flow-sheet was formulated and mCi levels of 90Sr recovered. 相似文献
14.
Eliane S. C. Temba Aluísio S. Reis Júnior Ângela Maria Amaral Roberto P. G. Monteiro 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(3):631-635
A methodology for the determination of 90Sr in low- and intermediate-level radioactive wastes from nuclear power plants is presented in this work. It is a part of
a methodology developed for the sequential radiochemical separation of radionuclides difficult-to-measure directly by gamma
spectrometry in these radioactive wastes. The separation procedure was carried out using precipitation and extraction chromatography
with Sr Resin, from Eichrom and the 90Sr was measured by liquid scintillation counting (LSC). Optimum conditions for the pretreatment, separation and LSC measurements
were determined using simulated samples, which were prepared using standard solutions and carriers. The procedure showed to
be rapid and achieved a good chemical yield, in the range 60–90%, and a detection limit of 6.0 × 10−4 Bq g−1. The method was also tested by participation in a national intercomparison program, with aqueous samples, with good agreement
of results. 相似文献
15.
N. Vajda A. Ghods-Esphahani E. Cooper P. R. Danesi 《Journal of Radioanalytical and Nuclear Chemistry》1992,162(2):307-323
A simple and rapid method has been developed for the separation and determination of total radiostrontium in soil. The method consists of three basic steps: oxalate precipitation to remove bulk potassium, chromatographic separation of strontium from most inactive and radioactive interferences utilizing a crown ether (Sr. Spec, EIChroM Industries, Il. USA) and oxalate precipitation of strontium to evaluate the chemical yield. Radiostrontium is then determined by liquid scintillation counting of the dissolved precipitate. When 10 g samples of soil are used, the sensitivity of the method is about 10 Bq/kg. The chemical yield is about 80%. The separation and determination of radiostrontium can be carried out in about 8 hours. 相似文献
16.
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
17.
R. Dabbagh H. Ghafourian A. Baghvand G. R. Nabi H. Riahi M. A. Ahmadi Faghih 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(1):53-59
The ability of living filamentous cells of the cyanobacterium Oscillatoria homogenea to separate stable strontium and 90Sr from aqueous solution is demonstrated in this study. On a basis of filamentous cell biovolume, the removal were 43.78 nM·ml·(mm3)−1 and 3129.48 mBq·ml·(mm3)−1 after 240 hour incubation. The optimum pH for strontium uptake is 9±0.3. The increasing biovolume of the blue-green alga
elevates sorption. In the liquid culture containing 21.2 mm3·ml−1 filamentous cells and 1000 nM·ml−1 initial strontium concentration, the maximum strontium removal was 455.34 nM·ml·(mm3)−1. At 1200 Lux illumination, the maximum removal value was 58.62 nM·ml·(mm3)−1, and at the initial strontium concentration of 6590 nM·ml−1, 235.40 nM·ml·(mm3)−1 removal was observed. The experimental data fitted to Langmuir isotherm and the model parameters and correlation coefficient
(R
2) were q
max = 7.143 μg·(mm3)−1, b = 0.003 and 0.99, respectively. 相似文献
18.
Filip Kužel Petra Staffová Irena Špendlíková Jan John Ferdinand Šebesta 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(3):729-734
Solid extractants containing di-(2-ethylhexyl)phosphoric acid (HDEHP) in the support based on modified polyacrylonitrile (PAN)
were studied for the determination of 90Sr by means of measuring the activity of its separated 90Y daughter. In this paper, 152Eu and 133Ba were used as chemical homologues of 90Y and 90Sr. For these radionuclides, dependences of mass distribution coefficients (D
g) on the nitric acid concentration were measured for several types of HDEHP-PAN solid extractants. The mechanism of the Eu3+ and Ba2+ ions extraction was confirmed to follow the theoretical two-phase equation for the chelating extractants. Further, the influences
of the presence of nitrates, calcium and iron ions on the values of D
g(Ba, Eu) were determined concentrating on the possibility of masking the iron ions by the addition of the ascorbic acid. This method
was tested on the solution simulating the leachate of ashed green plant sample. The results obtained make the application
of solid extractants containing HDEHP in PAN support prospective for 90Sr determination. 相似文献
19.
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
20.
Strontium
isolation from natural samples with Sr resin and subsequent determination of 90Sr</p>
</p>
Ž. Grahek K. Košutić M. Rožmarić-Mačefat 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(2):179-190
The
reliability of an 90Sr determination method was tested using an Sr
extraction chromatographic resin for strontium isolation. The 90Sr-content
in samples of vegetables, soil and water (obtained from Environmental
Measurement Laboratory, USA) were determined and the results were controlled by
classical methods and by using an anion-exchanger and an alcohol solution of
nitric acid for the strontium isolation. These methods were previously tested
by determining 90Sr in IAEA 326 and 327 samples of soil. It is shown
that the isolation process with Sr resin is simpler and faster than the
classical and mixed solvent anion-exchange methods. The efficiency of isolation
on a Sr column depends on the resin quantity and separation conditions; and is
the highest with a Sr column, compared to the classical and anion-exchange
methods. Experimental data and theoretical models were used to calculate the
parameters that enable the estimation of optimum dimensions of the column for
isolation. A simple relation is proposed for the calculation of breakthrough
volume, which defines the sample and eluent volumes for an optimal strontium
isolation.</p>
</p> 相似文献