Journal of Radioanalytical and Nuclear Chemistry

On the basis of vapor phase osmometry data the activity coefficients of TBP, D2EHPA and some tertiary amines have been calculated. The applicability of various methods for the evaluation of association constantsK i in the extraction systems is presented.

The adsorption characteristics of 113Sn(IV) and 113mIn(III) on glass beads from NaCl solutions have been studied. On the basis of these studies, 113Sn-113mIn generator has been prepared by adsorbing 113Sn on the glass beads column. 113mIn has been eluted by the 0.16M NaCl solution with pH 3.0, remaining 113Sn adsorbed on the glass beads. The yield of 113mIn has been about 73% in the first 6 ml of eluate, while the breakthrough of 113Sn has been about 0.042%.

Glassy tin arsenate, Sn(HAsO4)2·2.7H2O (SnAs) was prepared and characterized. The uptake of lanthanide ions La3+, Sm3+, Eu3+, and Yb3+ was followed on the glassy tin arsenate in HNO3 solution at pH 1,2 and 4. The radiotracers are140La,153Sm,152mEu, and175Yb. 500 μl (4.0·10−5 mmole) of each solution of the tracer as a mixture plus 7.5 ml HNO3 solution at the desired pH were equilibrated with 0.1g of SnAs. The selectivity order (K d values) was found to be dependent on the pH. At pH 2 theK d values were high for all the studied metal ions [Yb (2065.4)>La (1976.1)>Sm (1826.4)>Eu (1754.4)]. TheK d values at pH 1 and 4 are quite low for all the metal ions studied. At pH 1 they range from ≈144 to 156 and at pH 4 they range from ≈70 to 79.

The aim of this work is the development of the immunogenic properties of 17beta-estradiol to produce polyclonal antibody for radioimmunoassay purposes. Poly(acrylamide–maleic acid) gel [P(AAm–MA)] was prepared by the template polymerization. Polyacrylamide (PAAm) was used as a template for the polymerization of MA in aqueous solution using gamma rays as initiator. Then a comparative study of estradiol trapped in the prepared polymer gels versus estradiol conjugated to bovine serum albumin (BSA) was carried out. Ten rats divided into two groups were injected according to specific protocol. The immunogenic properties of both produced polyclonal antibodies were studied. In conclusion, the results revealed that the similar immunogenic properties with specific radiolabeled tracer were obtained.

Self-absorption correction of low-energy (<100 keV) γ-radiation is a much debated subject when applying low-energy γ-rays for dating purposes. Some investigations have hitherto focused on the possibility of using either irradiating of the sample and subsequent absortiometry or introducing physical correction. In the present paper an automatic procedure was elaborated using the occurrences of other low-energy γ-lines in the sample, those of234Th. Theoretical considerations are described on the basis of the mass absorption coefficients as a function of energy and atomic number. These considerations are verified by experiments with rock forming oxides and carbonates mixed with Standard Reference Material. Finally, an example is given for the application of the self-absorption correction approach.

Two new methods for quantitative determination of the role of scavengers of OH radicals in the radiation protection of various microorganisms were studied. The yeast and bacteria were irradiated with gamma or UVC radiations having quite different effect on living cells. Both methods based on the counting of colonies arising from surviving cells proved to be able to describe quantitatively the protective effect of scavengers. The described method may be helpful for study of the radiation protection of cells, radiation stability of DNA or the permeability of the cell membrane.

Plutonium nitrate solutions contain a large number of chemical species and they exhibit significant deviations from ideal behavior. Modeling this system is challenging. A model that includes all known chemical species and accounts for nonideal solution behavior could contain several hundred unknown parameters, but insufficient published data exists for evaluating large numbers of parameters. A practical model of plutonium nitrate solutions, therefore, must be a compromise between the number of chemical species included and the number of parameters that can be evaluated from available data. A practical model of acidic plutonium nitrate was developed. The model, which was based on an extended UNIQUAC–Debye–Hückel equation, captures the essential behavior of the system with a minimum number of chemical species. It is capable of representing the vapor–liquid equilibrium data for the nitric acid–water system, the activity of water in the plutonium nitrate-nitric acid–water system, the distribution of plutonium–nitrate complexes in aqueous nitric acid solution, and plutonium adsorption on an anion exchange resin.

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.