Journal of Radioanalytical and Nuclear Chemistry最新文献

Accurate quantification in gamma-ray spectrometry requires precise correction for self-attenuation effects, especially in heterogeneous matrices. In this study, we determine the self-attenuation coefficient of a uranium ore sample (6.6 weight % uranium and approximate 93.4 weight % SiO₂) using two methods: direct measurement from the ore’s intrinsic gamma ray emissions and an external Eu-152 source applied to the ore matrix. A correction multiplier is developed to reconcile deviations observed with increasing sample mass. The dual-method approach enhances reliability in determining radionuclide elemental concentration and/or raioactivities in high-Z materials.

With the growing interest in using radium-226 (Ra-226) as a source material to produce essential radionuclides for targeted alpha therapies, the global demand for Ra-226 has surged, rendering its acquisition difficult. The shortage necessitates the exploration of alternative pathways to obtain this isotope beyond traditional commercial vendors. Legacy radium sources remain widespread due to Ra-226’s historical use but require the removal of ingrown daughter products to obtain a pure Ra-226 product. A straightforward and effective purification method for legacy Ra-226 ampoules has been developed using cation exchange chromatography, enabling the reliable conversion of legacy materials into high-purity Ra-226 solutions.

The pollution issue of uranium-containing wastewater generated from the rapid development of the nuclear energy industry has attracted widespread attention. To efficiently remove uranium from wastewater, six types of SiO₂ modified with g. lycine, β-alanine, γ-aminobutyric acid, 6-aminocaproic acid, 8-aminocaprylic acid, and 11-aminoundecanoic acid, with different carbon chain lengths and terminal amino groups, were successfully prepared via the sol–gel method. The materials were characterized using XPS, FTIR, BET, XRD, and SEM. Amino groups are important functional groups for efficient coordination with uranyl ions. The effects of chain length on the properties of amino acids and uranium adsorption capacity were investigated through batch experiments. The results indicate that the introduction of amino acids can effectively enhance the uranium adsorption capacity of SiO₂. Notably, SiO₂/6-aminocaproic acid demonstrates the fastest adsorption rate (k_id = 56.42 mg·g⁻¹·min^−0.5) and a maximum adsorption capacity of 221 mg·g⁻¹, surpassing that of unmodified SiO₂ (q_e = 50.25 mg·g⁻¹). The chain length of SiO₂/6-aminocaproic acid aligns with the size of uranyl ions, while the terminal amino groups maintain coordination. Grafting amino acids onto the SiO₂ surface can combine the hydrophobic effect of the chain length and the benefits of multidentate coordination to achieve a synergistic effect. The elution rate remains excellent after five adsorption–desorption cycles, indicating recyclable and reusable capabilities. This research offers valuable ideas for materials modified with amino groups or other functional groups (like phosphate and sulfonic acid groups).

Iron phosphate materials (FeP-A(B)) were synthesized via a one-pot strategy, with their compositions tailored by adjusting the phosphate acid content and the Fe³⁺/Fe²⁺ ratio. Among these, FeP-2(1) exhibited the best U(VI) adsorption capacity. Batch experiments revealed a maximum adsorption capacity of 147.4 mg g⁻¹ at pH 4.5, reaching equilibrium within 12 h, surpassing several reported adsorbents. Moreover, FeP-2(1) showed excellent selectivity and maintained high removal efficiency over five consecutive cycles, indicating strong reusability. Mechanistic analysis confirmed that U(VI) uptake occurs mainly through complexation with surface phosphate groups. These findings highlight FeP-2(1) as a promising adsorbent for U(VI) remediation in aqueous systems.

To effective reduce U(VI) to U(IV) in HNO₃ solution, constant-potential electrolysis was conducted in different conditions to optimize the electrolysis conditions. The results show that U(VI) reduction efficiency was highest at − 300 mV in 3–6 M HNO₃ solution. Ru(III), Zr(IV), and Fe(III) all reduced U(VI) reduction efficiency, particularly Fe(III). Adding hydrazine to solution containing U(VI) and Fe(III) suppressed HNO₂ accumulation and enhanced U(VI) electroreduction. The electroreduction of U(VI) in the presence of multiple impurity ions and different HNO₃ concentrations was also conducted, indicating that 6 M HNO₃ is optimal for U(VI) reduction.

Prostate-specific membrane antigen-targeted radioligand therapy is a potent new treatment that improves survival and quality of life in metastatic castration-resistant prostate cancer patients. However, these require high radiation doses and frequent delivery; hence, innovative strategies to develop future therapeutic agents are needed. Gold nanoparticles’ ability to deliver a large payload of radionuclides, favorable bioavailability, modifiable surfaces, and ability to induce hyperthermia could potentially enhance efficacy when combined with targeted radioligand therapeutic agents. Recent advances in targeted gold nanoparticles and their radiolabeling with potential radioligands, radiobiology, and photothermal effects to facilitate combination therapies are discussed in this review.

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To investigate the effects of wildfire-induced structural changes in organic soils on radon release, nitrogen adsorption and radon exhalation experiments were conducted on soils with 1–5% organic matter under 100–600 °C thermal treatments. Radon release was jointly controlled by organic matter and thermal disturbance, peaking at 3% organic matter, while higher contents reduced pore connectivity via cementation. Exhalation showed a nonlinear two-stage response: it increased linearly from 100 to 300 °C, peaking when pore volume (0.0646 cm³/g) and specific surface area (14.85 m²/g) were maximal (~ 1.3 × the 100 °C rate), then decreased by ~ 17% up to 600 °C due to mineral transformation and pore collapse. This study provides a reference for radon risk assessment in high-temperature environments.

Lithium isotopes (⁶Li, ⁷Li) underpin nuclear energy. Metal electromigration for isotope separation remains understudied. In this study, stainless steel capillaries filled with metallic lithium were subjected to a constant current of 20 A, achieving a maximum separation factor of 1.018. By incorporating the cooperation between electric and gravitational fields, the maximum separation factor was increased to 1.025, with ⁶Li and ⁷Li fractions each containing ~ 20% of total lithium. This research broadens the methods of electromigration separation for lithium isotopes and is anticipated to provide new insights for the separation of metal isotopes.

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Based on a study of radon release from southeastern Hunan granite, a Python-based fracture extraction software was independently developed to analyze the fractal characteristics of surface fractures. Fractal dimensions were 1.7560–1.8664, indicating high complexity. The study found that the correlation between the radon exhalation rate and fracture fractal characteristics was weak before standardization (0.105). However, after standardization by uranium content and radium activity, the correlation significantly increased (to 0.305 and 0.417, respectively), confirming that standardization more accurately reveals the relationship between fracture characteristics and radon exhalation rate. Both are greatly influenced by uranium and radium content.

This study aims to determine the origin of water, its recharge processes, and its circulation time within the aquifer by examining the hydrogeochemical properties and environmental isotope (δ¹⁸O, δ²H, and ³H) composition of groundwater in the southern recharge area of Tuz Gölü (Aksaray, Turkey). The study area consists of lithologically similar, horizontally flat limestones and alluvial units with low topographic gradient. Within the scope of the study, samples were collected from Miocene–Pliocene-aged limestones and Pliocene–Quaternary alluvial aquifers during dry (October 2019) and rainy (May 2020) periods. The analysis results indicate that Ca–Mg–HCO₃ type waters are dominant in recharge areas, while Na–Cl type waters are dominant in discharge areas. This situation reflects the water–rock interaction, carbonate weathering, and evaporation process that occur during the movement of groundwater within the aquifer. The stable isotope values (δ¹⁸O: − 8.47 to − 11.11‰; δ²H: − 64.12 to − 75.94‰) fall below the Global (GMWL) and Adana Meteorological Water Lines (AMWL), indicating continental precipitation and evaporation effects. Tritium (³H) values (0–6.51 TU) indicate that groundwater is largely semi-modern and ancient, thus revealing long circulation and limited renewal in the aquifer. A comprehensive evaluation of hydrogeochemical and isotopic data reveals that slow renewal and long circulation times prevail in carbonate-dominated aquifers. These findings highlight the hydrogeological sensitivity of the Tuz Gölü Basin by revealing that excessive groundwater extraction causes a decrease in the water level in Miocene-Pliocene limestones, thereby increasing the likelihood of karstic depressions and sinkholes forming.