Journal of Radioanalytical and Nuclear Chemistry最新文献

46 MeV alpha particle irradiation on ^natY produced ⁸⁹Zr and ⁹⁰Nb. After ⁹⁰Nb was decayed out, separation of ⁸⁹Zr from bulk yttrium was carried out using caffeine extracted from black tea leaves. At 2 M Na₂SO₄ concentration caffeine was precipitated, and ⁸⁹Zr was found to be preferentially precipitated with caffeine at natural pH of Na₂SO₄. With 10 mg caffeine, ~ 56% of ⁸⁹Zr was precipitated with caffeine along with 1.5% of bulk yttrium.

This study investigates the natural radioactivity levels in Thiruvananthapuram, Kerala, focusing on uranium (²³⁸U), thorium (²³²Th), and potassium (⁴⁰K) concentrations in rock samples collected from various locations. Rock samples were collected and analyzed using gamma ray spectroscopy with NaI(Tl) detectors to determine activity concentrations and radiological parameters. The results reveal varying concentrations of ²³⁸U (5.05 to 200.31 ± 11.85 Bq kg⁻¹), ²³²Th (5.04 to 632.73 ± 37.44 Bq kg⁻¹) and ⁴⁰K (556.89 ± 3 2.95 to 2072.2 ± 122.61 Bq kg⁻¹) with mean values of 49.12 Bq kg⁻¹, 257.71 Bq kg⁻¹, and 1451.56 Bq kg⁻¹ respectively. Radiological parameters (Ra_eq, D_R, AED, H_(in,out), GI, RLI, ELCR_{(in, out)}, AUI, AGEDE) were also calculated. Correlation and ratio analyses further highlight relationships between uranium, thorium, and potassium concentrations, revealing their geological associations and implications for radiological hazards. This study underscores the importance of monitoring natural radioactivity in urban environments to mitigate potential health impacts and ensure public safety.

Uranium hexafluoride (UF₆) is a significant concern for material accountancy and verification in the international safeguards community. Verification of the contents of UF₆ cylinders is generally attempted with gamma spectroscopy but the current methods assume a uniform, homogeneous UF₆ mass distribution within the cylinder. In this work, it was found experimentally and confirmed via modeling, that under an external heat load (the sun), the UF₆ and its daughter products undergo fractionation in the cylinder. This fractionation of the UF₆ and daughter products can cause an errant measurement of the enrichment of the cylinder when using the current verification methods.

Tritium-containing waste oil, a typical pollutant from the atomic energy industry, has attracted significant attention to deal with it. Adsorption fixation is an important way to treat waste oil, and the development of suitable adsorption materials represents a significant research challenge. In this paper, polyvinyl alcohol-diatomite hybrid aerogel (PVA/D-A) was successfully prepared by freeze-drying method. Taking pump oil as the main representative of tritium-containing waste oil, the adsorption ability of diatomite and PVA/D-A to pump oil was measured, including adsorption capacity (Q, g/g) and oil penetration rate (OPR, %). The experimental results indicate that the Q and OPR of diatomite are 0.35 g/g and 30.25%, respectively, while the PVA/D-A is 7.45 g/g and 1.29%, respectively. Concurrently, the incorporation of diatomite makes the material stronger and more durable. This paper provided new insights for treatmenting tritium-containing organic waste oil and expanded the application fields of PVA and diatomite.

Radiopharmaceuticals are medicinal products used for the diagnosis or treatment in nuclear medicine, consisting of a radioactive compound and generally a targeting pharmaceutical compound. Adverse drug reactions defined as harmful and unexpected responses that occur when administered at normal doses, have less severity and less incidence with radiopharmaceuticals than with conventional drugs. Though adverse reactions observed with positron-emitting radiopharmaceuticals are lesser and milder than both conventional drugs and other radiopharmaceuticals such as therapeutic and SPECT radiopharmaceuticals, adverse reactions that cannot be ignored still occur. Therefore, this review aims to raise awareness about adverse reactions observed in positron-emitting radiopharmaceuticals.

Radionuclides removal and immobilization are crucial issue for liquid radioactive waste management. Zr-Ca-Mg and Ti-Ca-Mg phosphates performance for Cs⁺ ions adsorption and immobilization was studied. Adsorption of stable Cs⁺ on composite phosphates was well described by Sips model and pseudo-second order kinetics. Zr-Ca-Mg samples had the highest Cs⁺ adsorption capacity (< 2.40 mmol/g) compared to Ti-Ca-Mg phosphates (< 2.18 mmol/g). The samples with high Ti and Zr content were characterized by enhanced efficiency of ¹³⁷Cs radionuclide adsorption (K_d > 10⁴ mL/g) in wide range pH of 4.0–10.0. Metal phosphates calcined at 1000 °C shown the safe immobilization of Cs⁺ ions.

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In this study, a reactive-crystallization method was introduced for the purification of LiCl–KCl salt waste generated in pyrochemical processes, wherein the salt was purified and impurities were precipitated using Li₂CO₃. The element separation efficiencies of group I/II and rare-earth elements were found to be > 90%. In addition, the metal corrosion generated during this process was mostly present in the precipitate phase, and the dissolved metal corrosion in the eutectic salt was suppressed to a few ppm. The feasibility of this process was confirmed by thermodynamic calculations. Reactive-crystallization can also be applied to other salt waste systems, such as MSR nuclear fuel treatment and molten salt chemistry for impurity purification.

Responding to the need for radioactive waste disposal, the static and dynamic adsorption of Eu³⁺ on TODGA-C resin in HNO₃ was investigated. The findings indicated that the adsorption of Eu³⁺ on TODGA-C adheres to the quasi-second-order kinetic model. Additionally, the distribution coefficient for Eu³⁺ adsorption on TODGA-C reaches 10⁵ mL/g in 4 mol/L HNO₃. Under the conditions of 3.5 mol/L HNO₃, a flow rate of 3.6 mL/min, and an initial Eu³⁺ concentration of 10 mg/L, the Thomas rate constant was found to be 1.2 mL/(mg·min), with a dynamic saturation capacity of 15 mg/mL.

c-Met, a transmembrane receptor tyrosine kinase, is implicated in the process of tumor progression and metastasis and is regarded as a therapeutic target with its small molecular inhibitor, such as crizotinib. However, there are few radiolabeled small molecular inhibitors used for the evaluation of c-Met expression. Herein, a ^99mTc labeled crizotinib derivative ([^99mTc]Tc-HYNIC-Cri) was prepared with high stability in vitro, and there was a significant difference in biodistribution and SPECT studies between U87 MG tumors with high c-Met expression and A549 tumors with low c-Met expression. These initial findings reveal that [^99mTc]Tc-HYNIC-Cri holds great potential for imaging of c-Met–positive tumors.

To solidify make ¹³⁷Cs with long half-life solidified in high level waste liquid, cesium zeolite was synthesized from fly ash without adding template. The effects of basic cations (Na⁺ or K⁺) on the binding force and interaction mechanism of cesium zeolite and Cs(I) were calculated and evaluated by first principles. The results indicate that a spherical granular cesium molecular sieve with a particle size of approximately 5 μm can be synthesized from alkali-pretreated fly ash following a hydrothermal reaction at 180 °C for 20 h, achieving a cesium solidification rate exceeding 40%. The coexistence of Na(I), K(I), and Cs(I) had minimal impact on the synthesis of the cesium molecular sieve.