Journal of Radioanalytical and Nuclear Chemistry最新文献

This study investigates the solidification of liquid organic waste (LOW) using cement enhanced with bentonite clay to improve mechanical performance. Cement matrices containing 6–10% bentonite (2% increments) and LOW contents of 16–20% (by water) were evaluated. Compressive strength was tested after 7, 14, 21, and 28 days, while porosity and water absorption were measured after 14 days. The optimal formulation, with 8% bentonite and 28 days of curing, achieved the highest strength, showing a 33.33% improvement over previous studies. These results demonstrate that bentonite addition effectively enhances the strength and quality of cemented waste forms for radioactive LOW immobilization.

Programmed death-ligand 1 (PD-L1) represents a pivotal target for immune checkpoint blockade therapy. This study developed a novel PD-L1-targeting SPECT probe [^99mTc]Tc-G₃C-2CBM based on dimeric 2-bromo-3-biphenyl (CBM) scaffold design. The probe was designed to enable bivalent interactions through dual CBM domains, exhibiting > 98% radiochemical yield and excellent in vitro stability. Cellular uptake studies revealed significantly higher accumulation in PD-L1-overexpressing A375-hPD-L1 cells compared to A375 cells (14.15 ± 2.11% vs. 5.89 ± 0.55% at 4 h; uptake ratio = 3.20). The probe displayed favorable binding affinity (K_D = 36.54 ± 7.28 nM) and inhibitory potency (IC₅₀ = 69.62 ± 5.15 nM). In vivo SPECT imaging confirmed tumor-specific accumulation, though accompanied by notable hepatic uptake. These results demonstrate that CBM dimerization is a feasible approach for retaining PD-L1 binding and may provide a basis for the future development of multivalent radiotracers.

This study evaluates the microDiamond detector (PTW 60019) for small-field dosimetry and introduces a cubic correction model (R² = 0.86) to account for its over-response in very small fields. Measurements on a Clinac IX (6 MV) were benchmarked against an A28 chamber and Gafchromic EBT3 film. Output factor corrections derived from the cubic model showed high agreement with values obtained using the Daisy Chain method recommended in IAEA TRS-483. Post-correction, microDiamond and EBT3 values agreed within 2.5%. These findings support the microDiamond’s suitability for stereotactic small-field dosimetry when model-based corrections are applied.

This study investigated the sorption of europium on boehmite by batch method and explore the effects of solid–liquid ratio, pH, ionic strength and the addition of EDTA on sorption. Time-resolved fluorescence spectroscopy was employed to elucidate the sorption mechanism. The work found that under acidic conditions, the sorption of Eu(III) on boehmite surface is controlled by outer-sphere surface complexation, while under alkaline conditions, it shifts to inner-sphere surface complexation. Equimolar concentrations of EDTA only hinder the sorption in alkaline systems. Moreover, the higher concentration EDTA can reduce the sorption across the pH range.

Cancer remains a major cause of mortality, necessitating the exploration of novel therapeutic and diagnostic strategies. Quercetin is known for its antioxidant properties that may counteract carcinogenesis by neutralising free radicals. Therefore, it might be suitable to be used as a radiotracer. This study aimed to evaluate the biodistribution of technetium-99m-labelled quercetin ([^99mTc]Tc-quercetin) in a carcinogen-induced colorectal cancer murine model. Quercetin was successfully radiolabelled with technetium-99m, achieving a high radiochemical yield. The radiolabelled compound was then administered to tumour-bearing mice, and its biodistribution and pharmacokinetic profiles were evaluated. [^99mTc]Tc-quercetin demonstrated high accumulation in colorectal tumour regions, with rapid systemic clearance and widespread tissue distribution observed in pharmacokinetic profiling. The [^99mTc]Tc-quercetin holds promise as a potential radiotracer for colorectal cancer imaging, providing important insights into its biological behaviour and diagnostic potential.

The present study investigates the effect of ionizing radiation on the separation of radioactive elements via DCC with NTA-based eluents, using an external irradiation model. The separation efficiency was investigated within the absorbed dose range of 0–1.7 MGy per eluent. As the absorbed dose increases, the pH of the filtrate rises, the concentration of the eluent decreases, and the process accelerates. Initially, there is an increase in the concentration of emerging elements, which subsequently decreases. The primary finding was that an absorbed dose of up to 0.4 MGy per eluent and up to 3 MGy per sorbent improves the separation.

To ensure the reliability of measurement results from radioactive aerosol monitors, it is necessary to study the preparation technology for radioactive aerosol filter membrane standard source. In this work, a preparation system for radioactive aerosol filter membrane standard sources was developed, consisting of a radioactive aerosol generation unit, a radioactive aerosol sample preparation unit, an aerosol particle size measurement unit, and an exhaust gas treatment unit. Using this system, ²⁴¹Am filter membrane sources of different activities were prepared. Test results show that the relative error of the prepared ²⁴¹Am filter membrane sources, when measured by different instruments, is ≤ 5%.s

This study investigated the remediation of acidic uranium mine groundwater using SRB in a horizontal-flow reactor. Raising the pH from 3.5 to 4.5 shortened the time required for effluent sulfate to drop to ≤ 350 mg/L from 38 to 28 days, while the uranium concentration remained below 0.5 mg/L. Optimal removal occurred at 0.7 mL/min. U(VI) was immobilized via microbial reduction, co-precipitation (e.g., CaU(PO₄)₂, FeS), and surface complexation. Immobilized uranium remained stable under harsh conditions (pH 2, NO₃⁻, aeration), with release rates below 2.68%, 0.16%, and 0.5%, respectively. This study supports remediation strategies for acid in-situ leached uranium mines.

The remediation of trace cobalt (Co²⁺) in wastewater remains challenging. This study prepared a magnetic graphitic biochar (MGBC-900) from spent mushroom substrate via one-step pyrolysis with FeCl₃. MGBC-900 exhibited an ultrahigh specific surface area and excellent adsorption capacity (138.97 mg g⁻¹) for trace Co²⁺. The removal efficiency reached 99.10% at ~ 7 mg/L, maintaining 94.50% in simulated electroplating effluent. The adsorption mechanism is proposed to involve graphitic π-electron coordination and Fe–O complexation. MGBC-900 also showed good reusability. This work presents a sustainable strategy for trace cobalt removal using agricultural waste-derived biochar.

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