Thorium Removal, Recovery and Recycling: A Membrane Challenge for Urban Mining.

Although only a slightly radioactive element, thorium is considered extremely toxic because its various species, which reach the environment, can constitute an important problem for the health of the population. The present paper aims to expand the possibilities of using membrane processes in the removal, recovery and recycling of thorium from industrial residues reaching municipal waste-processing platforms. The paper includes a short introduction on the interest shown in this element, a weak radioactive metal, followed by highlighting some common (domestic) uses.

Performance evaluation of radon monitors at IFIN-HH, Romania.

Starting in 2022, the calibration of various radon monitors received from customers was performed for the first time in Romania by LMRI at IFIN-HH, designated by CNCAN as a calibration laboratory. The purpose of the study was to analyze the radon monitors responses and their uncertainties, and finally compare their performance with the standard radon monitor AlphaGuard in order to improve the calibration process in the future. Measurement results and the uncertainty budgets are presented in the paper.

Intercomparison of Radon Flux Monitors at Low and at High Radium Content Areas under Field Conditions.

Interlaboratory exercises are a good tool to compare the response of different systems to the same quantity and to identify possible inconsistencies between them. One of the main goals of the EMPIR 19ENV01 traceRadon project is to harmonize radon flux measurements based on different systems and methodologies. In the framework of the traceRadon Project, two radon flux intercomparison campaigns were carried out in October 2021 at high and at low radon source areas.

Operational Limits of the Bulk Hybrid Liquid Membranes Based on Dispersion Systems.

Liquid membranes usually have three main constructive variants: bulk liquid membranes (BLM), supported liquid membranes (SLM) and emulsion liquid membranes (ELM). Designing hybrid variants is very topical, with the main purpose of increasing the flow of substance through the membrane but also of improving the selectivity. This paper presents the operational limits of some kind of hybrid membrane constituted as a bulk liquid membrane (BLM), but which works by dispersing the aqueous source (SP) and receiving (RP) phases, with the membrane itself being a dispersion of nanoparticles in an organic solvent (NP-OSM).

Transport and Separation of the Silver Ion with -decanol Liquid Membranes Based on 10-undecylenic Acid, 10-undecen-1-ol and Magnetic Nanoparticles.

This paper presents a transport and recovery of silver ions through bulk liquid membranes based on -decanol using as carriers 10-undecylenic acid and 10-undecylenyl alcohol. The transport of silver ions across membranes has been studied in the presence of two types of magnetic oxide nanoparticles obtained by the electrochemical method with iron electrodes in the electrolyte with and without silver ions, which act as promoters of turbulence in the membrane. Separation of silver ions by bulk liquid membranes using 10-undecylenic acid and 10-undecylenyl alcohol as carriers were performed by comparison with lead ions.

60 years of absolute standardization of radionuclides by coincidence counting methods in the Romanian metrology laboratory.

This review paper presents the contribution of the Radionuclide Metrology Laboratory (RML) to the development and practical application of the coincidence counting methods. It is also intended to pay tribute to Dr. Enric Leon Grigorescu, the founder of our school of radionuclide metrology.

Absolute standardization of Co and analysis of the results obtained in two international comparisons.

The absolute standardization of Co-57 by the 4π(PC)-γ coincidence method, in efficiency extrapolation variant, is presented. An original, improved method, based on the use of the equivalent decay scheme, was applied; apart from the enhancement of efficiency, a diminution of extrapolation slope was obtained, lowering the extrapolation uncertainty. The results obtained in the participation at the supplementary comparison CCRI(II)-S6.

U nuclear decay data evaluation.

The evaluation of the nuclear decay data of U, a radionuclide of interest in nuclear medicine (targeted alpha therapy), was performed within the Decay Data Evaluation Project (DDEP) and an IAEA Coordinated Research Project. The nuclear decay data presented are: the half-life, decay energy, alpha-particle emission energies and probabilities, internal conversion coefficients and gamma-ray energies and emission intensities. These new data, obtained using the DDEP methodology and software tools, will be included in the DDEP database NUCLEIDE.

Experimental determination of some nuclear decay data in the decays of (177)Lu, (186)Re and (124)I.

A detailed experimental study of the radionuclides (177)Lu, (186)Re and (124)I was conducted at IFIN-HH, Radionuclide Metrology Laboratory. Absolute photon emission intensities in the decays of these radionuclides were measured by high-resolution gamma-ray spectrometry. Half-life measurements using a well-type ionization chamber were also performed.