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1.
A rapid separation of carrier-free 90Y in the aqueous phase of the water/nitrobenzene extraction system from an 90Y/90Sr generator is proposed. After a three-stage extraction, the chemical yield of 90Y in the final aqueous phase was almost 90%, while the 90Sr radionuclide impurity in this phase containing carrier-free 90Y was about 10–10%.  相似文献   

2.
A rapid extraction separation of trace amounts of yttrium from strontium with a nitrobenzene solution of sodium dicarbollylcobaltate (NaDCC) and 18-crown-6 in the presence of tetrasodium salt of ethylenediamine-N,N,N",N"- tetraacetic acid (Na4L) in the aqueous phase was developed. The separation factor a(Sr/Y) was substantially higher than 106. This water-nitrobenzene extraction system can be applied for efficient separation of carrier-free 90Y from 90Sr/90Y generator.  相似文献   

3.
Summary A rapid extraction separation of trace amounts of yttrium from strontium by a nitrobenzene solution of sodium dicarbollylcobaltate (NaDCC) in the presence of p-nonylphenylnonaethylene glycol (Slovafol 909) and tetrasodium salt of ethylenediamine - N,N,N',N' - tetraacetic acid (Na4L) in the aqueous phase was developed. The separation factor a(Sr/Y) was substantially higher than 105. This water-nitrobenzene extraction system can be applied for the efficient separation of carrier-free 90Y from 90Y/90Sr generator.  相似文献   

4.
The extraction of strontium(II) and yttrium(III) ions from aqueous solutions at various pH values into methyl isobutyl ketone containing I-phenyl-3-methyl-4-caprylpyrazolone-5 is described. Quantitative extraction of Sr and Y at pH 8.6–10 and pH 2.8–5.4 respectively is utilized for the carrier-free production of 90Y from 90Sr–90Y mixtures and 89Sr from neutron-irradiated yttrium oxide. A clean separation of these elements from each other and more than 95% calculated activities were recovered  相似文献   

5.
A rapid extraction separation of trace amounts of yttrium from strontium with a nitrobenzene solution of sodium dicarbollylcobaltate (NaDCC) in the presence of polyethylene glycol having mean relative molecular weight 400 (PEG 400) and tetrasodium salt of ethylenediamine-N,N,N,N-tetraacetic acid (Na4L) in the aqueous phase was developed. The separation factor (Sr/Y) was substantially higher than 106. This water-nitrobenzene extraction system can be applied for the efficient separation of carrier-free 90Y from a 90Y/90Sr generator.  相似文献   

6.

A radiochemical technique for estimation of 90Sr concentration by direct extraction of 90Y with bis (2-ethylhexyl) phosphate (HDEHP) in toluene was developed and standardized. About 90% 90Sr retained in the aqueous phase at the optimized pH 4–4.5. Cerenkov counting with 0.04 g mL−1 sodium salicylate as a wavelength shifter resulted in 7.5 fold increase its Cerenkov counting efficiency. The method was validated by estimating 90Sr in certified reference materials like, IAEA TEL 2016-03 drinking water, Spruce needle and IAEA-156 Clover. The interference of naturally occurring Ra and its β progeny especially Pb was eliminated by means of Cerenkov counting. Conventional radiochemical separation was used to compare 90Sr activity in effluent samples.

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7.
The separation of daughter nuclides in the carrier-free state from90Sr?90Y and140Ba?140La aqueous solution systems was performed by thin-layer chromatographic methods. (1) When a silica gel adsorbent and a developer of 1N NaCl, KCl, NH4Cl, CaCl2, SrCl2 or BaCl2 solutions was employed,90Y and140La were retained at the origin, while90Sr and140Ba advanced with the developer front. Addition of gypsum as binder to the silica gel prevented the separation of the140Ba?140La system, retaining both components at the origin. (2) When the140Ba?140La system was developed with water on a silica gel adsorbent containing 5% of gypsum, which was treated with various concentrations of nitric acid, the Rf value of140La increased with the concentration of nitric acid used, reaching a maximum of 0.98 at 0.1 N. The Rf value then decreased on the further increase of the concentration of nitric acid. When the same process was applied to the90Sr?90Y system, there was no separation. The radiochemical purities of90Y and140La obtained in the above two ways were more than 99%.  相似文献   

8.
Summary An extraction technique for the separation of 90Sr from a high excess of90Y has been developed. This procedure can be used for the determination of trace amounts of90Sr in90Y prepared by a radiochemical90Y/90Sr generator by liquid scintillation.  相似文献   

9.
Determination of 90Sr in environmental solid samples is a challenging task because of the presence of so many other radionuclides in samples of interest. This problem was dealt with by radiochemical separation of strontium followed by yttrium separation and Cerenkov counting of the high-energy ??-particle emissions of 90Y in order to quantitate 90Sr. In this work, an improved method is described for the determination of 90Sr in soil samples, through the separation of the daughter 90Y at equilibrium. The procedure is based on the HDEHP solvent extraction in combination with liquid scintillation spectrometry (LSS). A low background Quantulus has been optimized for low level counting of Cerenkov radiation emitted by the hard ??-emitter 90Y. The analytical quality of the method has been checked by analyzing IAEA Soil-375 reference materials. The analytical method has also been successfully applied to the determination of 90Sr for moss-soil samples in inter-laboratory exercises through IAEA??s ALMERA network. The chemical recovery for 90Y extraction ranged from 80 to 85% and the counting efficiency was 73% in the window 25?C400 keV.  相似文献   

10.
Summary A relatively simple chemical separation procedure has been developed for the simultaneous determination of89Sr and 9 0Sractivities in water samples and on aerosol-filters of the Nuclear Power Plant (NPP) Paks origin. The procedure combines the cation-exchange chromatographic (Dowex 50 WX 8 resin) and solid phase extraction (EIChroM Sr.Spec?, DC18C6 crown ether) steps. The beta-radiation of radionuclides can be measured directly after the chemical separation by LSC. The activities of89Sr,90Sr and90Y are calculated from an over determined set of equations using a method of constrained optimization technique. The equations are based on LSC measurements performed in three counting windows plus the90Sr-90Y decay law. The chemical yield of strontium is determined by ICP-AES. The lowest limits of detectable activity, for the measurement time of 600 minutes, are 30 mBq/sample and 18 mBq/sample for89Sr and90Sr, respectively.  相似文献   

11.
A rapid and very effective separation of carrierfree 90 Y in the aqueous phase of the water/nitrobenzene system from an 90 Y/90 Sr generator is proposed. After a twostage extraction separation, the radionuclide impurity of 90 Sr in the final aqueous phase containing carrierfree 90 Y is approximately 10 16%, while the chemical yield of 90 Y in this phase is practically 100%.  相似文献   

12.
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   

13.
N,N,N′,N′-tetra-2-ethylhexyldiglycolamide (T2EHDGA) has been used for the preferential extraction of 90Y from its mixture with 90Sr from HNO3 as well as HCl medium. The separation efficiencies have been found out under varying experimental conditions. The extracted species were determined from T2EHDGA concentration variation experiments carried out at 3 M nitric acid as well as HCl and were found out to be Y(X3)3·3(TEHDGA)(o) for both the extraction systems, where X = NO3 and Cl, respectively. Comparison of the T2EHDGA and TODGA based separation methods is also made. In order to avoid third phase formation, iso-decanol has been used as the modifier in all the studies. The modifier content was optimized to 30% for 4 M HCl and 20% for 6 M HNO3 as the feed aqueous phases. Separation schemes were developed for the separation of carrier free 90Y and the purity was checked by the half-life measurement method.  相似文献   

14.
An improved and rapid method for determination of90Sr via its daughter nuclide,90Y, in aqueous samples from the low-level radioactive wastes by Cerenkov counting was established. This technique is applicable to beta particles maximum energies greater than 0.263 MeV in aqueous solution. A comparison of90Sr determination by Cerenkov counting and standard wet chemical separation techniques indicates a high degree of correlation and excellent agreement. For a 20 ml aqueous sample following the prescribed experimental conditions and a 60 min counting interval, the detection limit was 0.20 dpm/ml (0.10 pCi/ml), and the relative deviation is less then 5%.  相似文献   

15.
2-Thenoyltrifluoroacetone has been offered as a mobile carrier in organic phase for the transport and selective separation of yttrium from aqueous media using a liquid membrane system. Perceivably, the use of n-propylamine (PA) in the source phase enhances the transport of yttrium ions. The extraction and stripping conditions have entirely been evaluated and explained. The suggested method has been utilized for the separation of yttrium(III) from its binary mixtures with strontium(II) and some other cations such as Ni2+, Co2+, Ag+, Fe2+, Al3+, Cu2+, Hg2+and Cs+ in aqueous solutions of pH 5.4 in the presence of PA, while 1 M nitric acid was acting as a stripping agent in the receiving division. Cyanide ion and 5-sulfosalicylic acid have been used as masking agents to minimize the interferences from different transition metal ions and Al3+ in the source phase, respectively. 90Y in secular equilibrium with 90Sr in the source phase, was transferred to receiving phase and separated completely from its long-lived parent isotope. The activity of the transported 90Y was found to decay with a half-life 64.17 ± 0.05 h. The purity of yttrium-90 was comparable or better than the other applied liquid membrane systems for purification of yttrium-90.  相似文献   

16.
An improved and rapid method is described for the determination of 90Sr in environmental samples, through the separation of the daughter 90Y at equilibrium. The procedure is based on the HDEHP solvent extraction in combination with liquid scintillation spectrometry (LSS). A low background QuantulusÔ has been optimized for low level counting of Cerenkov radiation emitted by the hard b-emitter 90Y. The counting efficiency was 60% and the background 0.53 cpm. The reliability and reproducibility of the method have been checked using IAEA reference materials. The chemical recovery for 90Y extraction ranges from 83 to 90%.  相似文献   

17.
A rapid method for the preparation of 87Y/87mSr radionuclide generator from a rubidium chloride target irradiated with 35 MeV α-particles is described. A simple two-step procedure is used to obtain a carrier-free 87mSr isotope with a high enough radiochemical yield and high purity in the final aqueous fraction.  相似文献   

18.
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   

19.
A method is described for the determination of89Sr and90Sr in samples of plant and animal origin. The Rehak-Feddersen method was modified to measure90Sr. Modification was made in the sample preparation and in the toluene-HDEHP [di(2-ethylhexyl)phosphoric acid] extraction. After the extraction of yttrium, strontium is separated with nitric acid and—calculating with a correction factor—89Sr can directly be determined. Namely,89Sr can be measured in an aqueous solution by a liquid scintillation technique with an efficiency of 30% while90Sr with 1.4% only. Quenching of the solution—depending on the composition—which may influence the measurement of90Y and89Sr was also examined. Detection limits and reproducibilities are given. Finally, evaluation of the experimental data is reported.   相似文献   

20.
Yttrium-90 is an important radionuclide known for its therapeutic application in nuclear medicine. Solvent extraction studies with N,N,N’,N’-tetra-octyldiglycolamide (TODGA) has shown that Y(III) is well extracted in 6 M HCl while at the same time, extraction of Sr(II) is very low leading to a separation factor (DY/DSr = 60,000). This property of TODGA can be exploited for the separation of Y from Sr. The aim of this present work is to produce carrier free 90Y by using Supported Liquid Membrane (SLM) based separation of Y and Sr with TODGA as the carrier. Solvent extraction studies with various diluents viz. 1-decanol, xylene, MIBK, chloroform etc. indicated that xylene and n-dodecane are most suitable as S.F. >50,000 are obtained. Based on the results, a SLM based separation scheme was developed using 0.1 M TODGA in xylene loaded on a microporous PTFE membrane as a polymeric support and 6 M HCl as feed and 0.01 M HCl as strip phase. The results appear promising for the development of SLM based Y-90 generator. The purity of the product was ascertained by the half life method.  相似文献   

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