Zsolt Revay
Editor-in-Chief
Journal of Radioanalytical and Nuclear Chemistry
The synthesis of super heavy elements (SHE) with atomic numbers 113-118 has been achieved in the 48Ca-induced reactions. The seventh period of the Periodic Table has been completed. Unique data on the nuclear-physical properties of isotopes of the new elements have been obtained. Pioneering experiments on the chemical properties of elements 112 (Cn), 113 and 114(Fl) have been carried out [1].
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CEA (French Alternative Energies and Atomic Energy Commission) is both the operator of important nuclear facilities all over the nuclear cycle, in charge of major new built or D&D projects and a R&D group with dynamic policy of technology transfer. The position of CEA in D&D is unique because of the number and the wide diversity of facilities under decommissioning, with some high level of...
Nuclear weapons test fallout studies – radioecology competence developed
Environmental radioactivity in Finland is an established research field and has long traditions. Research started at the Department of Radiochemistry, University of Helsinki and at the predecessor of the Finnish Authority for Radiation and Nuclear Safety (STUK) in the last years of 1950s. Also Finnish Meteorological...
The opportunities of measuring the identities and amounts of chemical elements by measuring the activities induced by bombardment with neutrons was conceived more than 80 years ago. During the decades, practioners worldwide have been inspired by the challenges of this neutron activation analysis methodology, by the needs from end-users and by technological innovations in irradiation and...
Nuclear forensic science is an evolving discipline which aims at re-establishing the history of nuclear material of unknown origin by using measurable material properties. The main focus of nuclear forensic science is on chemical and radiochemical parameters, such as isotope ratios, chemical composition, chemical impurities or products of radioactive decay for deriving information on the...
Since their discovery more than 10 years ago, the family of uranyl peroxide cage clusters has grown to more than 60 published members. These clusters, with diameters in the range of 1.5 to 4 nm, are soluble macro anions in water where they can persist for at least several years. This presentation will provide a brief overview of the structures of this family of polyoxometalate clusters, and...
The current open nuclear fuel cycle utilises only approximately one percent of the energy contained in natural uranium. Spent fuel recycling (as done e. g. in France) results in significantly increased fuel efficiency. Future multi-recycling strategies to be deployed in fast reactors will lead to further improvement, eventually rendering further uranium mining unnecessary if depleted uranium...
The coupling of chemistry setups to an electromagnetic separator is advantageous as this provides the necessary suppression of the primary beam and of products of multi-nucleon transfer reactions, as it was demonstrated in the first study on the carbonyl complex of Sg at GARIS (RIKEN, Japan) [1] and in experiments on Fl chemistry at TASCA (GSI, Germany) [2]. The combination of physical and...
With the perspective of improving nuclear energy fingerprint by reducing the waste volume and its long-term radiotoxicity, the Partitioning and Transmutation (P&T) strategy is being developed as a viable solution.[1, 2] Nowadays great efforts are constantly dedicated to the development of compact and efficient hydrometallurgical partitioning processes based on CHON compliant hydrophilic or...
Extraction behavior of trivalent europium from nitric acid with N,N,N’,N’-tetraoctyl-diglycolamine (TODGA) in different diluents was investigated. Systematic evaluation of diluent influence on the extraction behavior was performed. Sets of secondary alcohols, ketones and alkanes with increasing carbon chain from 5 to 10 carbons were used as diluents in solvent extraction experiments....
Recently we have determined the first ionization potential (IP$_1$) of lawrencium (Lr, $Z = 103$), which is the last member of the actinide elements, using an ISOL (Isotope Separator On-Line) equipped with a surface ion-source coupled to a He/CdI$_2$ gas-jet transport system at the JAEA tandem accelerator facility [1]. A good agreement between the measured IP$_1$-value and the theoretical one,...
With rapid growing of nuclear power plants in China, the safety management of spent fuel becomes most important issues. Accelerator Driven Sub-critical System (ADS) takes the spallation neutrons as external neutron source to drive the sub-critical reactor, which will provide the hard and wide neutron spectra, large flux and inherent safety. In order to increase the utilization rate of uranium...
Today’s state-of-the-art alpha-decay- and SF-detection systems for artificially produced superheavy elements (SHEs) consist of silicon-based detectors. For recent chemistry experiments with SHEs a thermochromatographic channel comprised of silicon solid-state detectors in a sandwich-like geometry (e.g., Cryo On-Line Detector [COLD], Cryo Online Multidetector for Physics And Chemistry of...
When irradiated nuclear fuel is dissolved in nitric acid and contacted with tri-n-butyl phosphate (TBP) during PUREX processing, many reactions can occur. There is the potential to form a range of insoluble species, especially when solutions are concentrated by evaporation, as occurs prior to high activity liquor storage or vitrification. By replacing TBP with CHON alternatives, many of the...
Usually extractants have been used as solution in diluents. Diluent influences on properties of extraction mixture very significantly. Hydrocarbons are traditional diluents. Unfortunately, hydrocarbons are low-polar compounds and therefore are not good as diluents for polar extractants.
Fluorinated diluents are possible alternative for hydrocarbons ones. Best studied polar fluorinated...
In-beam activation analysis, i.e. the combination of prompt gamma activation analysis (PGAA) using neutron beams from research reactors combined with neutron activation analysis (NAA), can in principle be performed at many neutron centers all over the world. Thanks to its strong beam flux (max. 6E10 cm^-2 s^-1), at Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany it has been successfully...
The separation of uranium(VI) and plutonium(IV) by solvent extraction from spent nuclear fuels has already been studied with several families of extractants such as trialkyl phosphate, phosphine oxides or monoamides. A new family of extractant containing the carbamide function (also called urea with the general formula R1R2NC(O)NR3R4) is currently studied in our laboratory. Only few...
The low-destructive nature of many neutron-based analytical techniques is a main argument for their application in archaeometry. Further advantages of these methods are the little sensitivity for the matrix composition, easy sample preparation and fairly low detection limits. A combination of two or more of these methods broadens the application possibilities. For instance, prompt gamma...
Lutetium-177 (177Lu) is a radionuclide with tremendous potential in radionuclide therapy. 177Lu based pharmaceuticals are applied in neuroendocrine tumour treatment and have been approved for prostate cancer treatment. We have proposed the idea of a 177mLu/177Lu radionuclide generator for 177Lu production based on the separation of the daughter...
A method for the simultaneous preconcentration of six environmentally relevant transition metals, namely cadmium, cobalt, copper, manganese and zinc, by cloud point extraction followed by their determination using neutron activation analysis (NAA) was developed. The method involved the use of a nonionic surfactant, namely PONPE-7.5, and the chelating agent 1-(2-pyridylazo)-2-naphthol commonly...
N,N'-dimethyl,N,N'-dioctylhexylethoxymalonamide (DMDOHEMA) is used to separate An(III) and Ln(III) from fission products in several liquid-liquid extraction processes (DIAMEX, EXAm, GANEX)$^{1-2}$ that aim at recycling actinides. One key to understand these processes is the stoichiometry of the complexes formed during extraction. Time-resolved laser fluorescence spectroscopy (TRLFS) poses, in...
Quaternary aeolian sediments, particularly loess–paleosol sequences constitute some of the longest and most detailed records of Quaternary climatic change and valuable data archives for paleoenvironmental reconstructions. In the Chinese Loess Plateau in north-central China, the loess horizons represent arid periods of increased influx of wind-blown dust when the dust-transporting winter...
PGAA (Prompt Gamma Activation Analysis) is an established nuclear analytical technique for the non-destructive determination of elemental and isotopic compositions. The neutron activation analysis research group in KAERI (Korea Atomic Energy Research Institute) has been developing a fake gold bar detection method using a PGAA. However, a real experiment to verify the detection method was not...
In this study, a rapid method using single column separation and fusion for determination of the uranium in environmental samples (e.g., soil, sediment, air particulate, etc.) is presented. Various certified reference materials (CRM) of soil and sediment were used to evaluate the accuracy and precision for the developed method. Samples were rapidly digested using an alkali fusion (LiBO2)...
Activated carbon (AC) is pores space bounded by the carbon atoms. Pores of AC are directive for its application. It was shown that, surface modified form of carbon-based materials, are promising sorbents for separation of various radionuclides. In our study 5 AC adsorbents (A-E) are prepared from cellulose wool by treating with different solutions and carbonized at the temperatures of...
Most hazardous elements contribute significantly to contamination of agricultural soils. Their content in the soil increases above background level due to anthropogenic influences as industry ballast and transportation and energy production, especially in the surface layer of the humus horizon. Accumulation of hazardous elements in the soil has a significant ecological impact on the speed of...
Chromatographic techniques are applicable in a wide spectrum of scientific fields and are also advantageous in different kinds of interdisciplinary research. By these techniques we are able to analyse compound composition of unknown samples, purity of solvents but they can be applied also for the preparation of analytes with subsequent analysis of stable or radioactive isotopes. Based on...
Graphene oxide (GO) has two important characteristics: (I) it can be produced by cost-effective chemical methods, and (II) it is highly hydrophilic and can form stable aqueous colloids to facilitate the assembly of macroscopic structures by simple and cheap solution processes. In this work, the possibility of using of GO and GO modified by Mn and Fe have been examined. In order to find...
Building of the first AMS laboratory in the Czech Republic has recently been started in co-operation of the Nuclear Physics Institute of the Czech Academy of Sciences (NPI), the Faculty of Nuclear Sciences and Physical Engineering of the Czech Technical University in Prague and the Institute of Archaeology in Prague of the Czech Academy of Sciences. The laboratory will be located on the...
Radioactive Fe-55 is generated by neutron activation of stable iron and, therefore, it can be found in materials from nuclear power plant, which should be decommissioned. It decays by electron capture and emits x-ray of 5.9 keV (24.5% probability). Because of the low energy of emitted ray, the attenuation effect is large and it occurs already in the sample itself, therefore it is the most...
The current concept of handling low-level liquid radioactive waste (LRW) consists of development of technological schemes providing efficient and cheap LRW treatment. In addition, such technologies ought to lead to compacting of radioactive waste in combination with long-term, reliable and safe isolation from the biosphere. Unfortunately, some types of waste from the nuclear industry still...
Deep eutectic solvents (DESs) have emerged as an interesting type of neoteric solvents and have shown their usefulness as environmentally benign sustainable alternative to the conventional organic solvents 1. DESs are eutectic mixtures of Lewis and Brӧnsted acids and bases, which can contain a variety of anionic and cationic species 2. The use of DESs in chemical synthesis and chemical...
Complex formation between actinide (An = Pu(IV), Th(IV), Am(III) and U(VI) and a hydrophilic anionic form of SO3-Ph-BTP4– ligand, L4–, in water was studied by liquid-liquid extraction experiments performed over a range of the ligand and HNO3 concentrations in the aqueous phase, at a constant concentration of nitrate anions at 25°C. The competition for An ions between the lipophilic TODGA...
A rapid method to determine plutonium in water is to separate it on microfiltration polymer membranes impregnated with antimony, zirconium, and manganese oxides or zirconium, titanium and other phosphates, having the highest efficiency for adsorption of plutonium. In addition, ballast salts are removed. A method was developed for determining the total activity of alpha emitters with...
This study proposes the approach to remove the contribution of Rn-222 from the measured gamma-ray spectra, which achieved from a HPGe spectrometry. Several scenarios of flushing the central detector volume with nitrogen gas to actively remove the radon isotopes were simulated to evaluate the effect of Radon on the low-background gamma-ray spectra. To quantify the gamma background a set-up was...
The NaBiO3 nano-sheets were syntheized by a facile method of oxidizing Bi3+ in alkaline solution. The as-syntheized products were used to adsorb Ce3+ in solution and characterized by XRD, SEM, TEM and XPS. The results show that the synthized products have nano-sheets structure with a size of ~50 nm and high selective adsorption performance on Ce3+. After adsorbtion of Ce3+, all Na cations in...
The wide use of radioactive materials in human activities leads to the accumulation of a significant amount of radioactive waste (RW). Therefore search for safe methods of handling with RW and analytical determination of their content in environment becomes the most urgent tasks. At present, uranium mining, nuclear fuel production, treatment of various types of RW, civil and military nuclear...
Fluorinated diluents have been considered as possible alternative for hydrocarbons. Among their advantages one can list particulary their chemical stability and in many cases high polarity. Unfortunately, the best studied polar fluorinated diluents such as meta- nitrobenzotrifluoride (F-3, MNBTF) or phenyl trifluoromethyl sulfone ( FS-13, PMTS) have density about 1.41 g/cm$^{3}$ and higher...
The analysis of wipe samples is of great importance in nuclear safeguards. Total reflection X ray fluorescence spectrometry as a trace nondestructive analysis method can preliminarily analyze the wipe samples and provide references for screening, making it easier to make follow-up analysis plans. The method of determining uranium in wiped samples by full reflection X ray fluorescence...
The Blanka tunnel complex, a part of the Prague City Ring Road, is with a length of about 5.5 km the longest road tunnel in the Czech Republic and the longest city tunnel in Europe. Designed to relieve the historic center of Prague from heavy traffic, it connects the area west of Prague Castle with the Trója district in the northeast. The construction of Blanka started in 2007. Initially due...
Neutron activation analysis (NAA) can be conveniently used to measure microgram amounts of arsenic. However, in biological materials major elements such as bromine, chlorine, and sodium can produce high activities resulting in poorer detection limits for arsenic. The 559.1-keV photopeak of 76As (half-life = 25.9 h) is particularly interfered with by the 554.3-keV photopeak of 82Br (35.3 h) and...
Ex-core monitoring of irradiated fuel rod leakage using general-purpose assembly of fault detection is based on identification of 85Kr release from leaking irradiated fuel assemblies. The sensitivity of this method is defined by minimum volume activity of this nuclide that is authentically measured in air mixture of leak-tight circulation circuit (LTCC) via the radiation monitoring system...
The bio-sorbent used in the study was prepared from wood-decay fungus Fomes fomentarius. The chemical modification of bio-sorbent with ferric hexacyanoferrate(II) (Prussian blue) for cesium sorption studies was used. The surface area was calculated by adsorption of argon at 77 K, in accordance to the method of Brunauer et. al, 1938. The surface area of the 0.5 mm grains was 39 m2 g-1. In...
Radionuclide 131I is used as a reference nuclide for monitoring of gas-aerosol emissions. Under the normal operating modes, 131I radionuclide release does not exceed admissible values, however, during conduction of some activities in the plant premises it can exceed admissible levels that can be potentially dangerous for personnel because of high toxicity of the iodine. In case of accident,...
Solving the problem of ensuring of the radioactive waste safe management from NPP is very relevant in the world due to the intensive development of nuclear energy, as well as environmental pollution because of technogenic accidents at NPP (Chernobyl, Fukushima). Natural aluminosilicates and modified products based on them can be promising materials for purification from radionuclides of...
For the analysis natural radionuclides, gamma spectroscopy, alpha spectroscopy and liquid scintillation counter(LSC) were used. Among them, LSC was widely used because it can be applied alpha, beta and gamma emitting nuclides. But some low activity nuclides are not analyzed because most of the LSC used 20 mL vial. Therefore, some radionuclide, such as H-3, are needed concentration. To improve...
The decommissioning of nuclear facilities (NF) has become more topical, primarily in Europe, but also in the USA and in Japan. This is mainly because the lifespans of the major parts of nuclear power plants are rapidly approaching their end, although in some cases the reasons for decommissioning are different (e.g. political). Another reason is that nowadays “immediate dismantling” is...
One of the crucial advantages of the PIXE (Particle Induced X-ray Emission) technique is its non-destructive approach to the sample treatment during the analytical process. Rare and precious environmental samples can be analysed in order to evaluate the concentration of individual elements presented in the specimen. Composition of various samples and material has been investigated using PIXE...
A theory of concurrent sorption as an instrument for predicting the conditions for desorption of radionuclides, Sr(II) in particular, from “contaminated solid – water” systems is formulated in this presentation. Typical isotherms of concurrent sorption are presented. Based on the sorption isotherm we analyze the possibility of desorption of traces of Sr(II) and Sr-90 from ion-exchange...
A new supramolecular composition containing a clozoborane salt UO2 [ B10H9S(C18H39)]2 ,
polyvinyl chloride (PVC) as a matrix and tris (2-ethylhexyl) phosphate. The membranes of various compositions with different ratios of membrane components were investigated.
The membrane with the best electroanalytical characteristics has the following composition:
Сs B10H9S(C18H37)2 : 1 – 3 % (mass),
tris...
The need for determining the U-235/U-238 isotopic ratio in a naturally occurring radioactive material (NORM) is increasing to warn a leakage of uranium into the environment. During the process of seeking a non-destructive method of analyzing natural matrices for uranium isotopes U-235 and U-238, a major source of uncertainty was found to be the gamma-ray intensities. Ra-226 and U-235 are...
Recently, the CENTA laboratory was established at Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava. The laboratory comprises the system for production of various ion beams from solid and gaseous samples, the energy and mass separation and the 3 MV tandem accelerator, that is used for acceleration of the ions up to tens of MeV. The beams can be used for several...
Radiocarbon dating is an exact dating method and its pioneer was the team of Professor F.W.Libby in the 1950s. This is the most significant and most commonly used 14C determination application. Within the carbon cycle in nature, 14 C is generated in the upper part of the atmosphere by the interaction of 14N with cosmic radiation 14N (n, p) 14C. Radiocarbon is relatively quickly oxidized to...
Low-level concentrations of primordial and cosmogenic radionuclides were determined in recently fallen chondrites and in meteorites from Mars and the Moon. The radionuclide measurements showed a wide range of concentrations of $^{22}Na$, $^{26}Al$, $^{46}Sc$, $^{54}Mn$ and $^{57}Co$. The absence of the neutron product ($^{60}Co$) in some of the meteorites indicates that their pre-atmospheric...
Radioactive waste contains large amounts of hazardous radionuclides. Among them, long lived radionuclides of 137Cs (half-life-time of 30 years) and 90Sr (half-life-time of 28 years) are considered as the most dangerous to human health and environment. The ion exchange technology is one of the most commonly used methods for safe treatment of radionuclide waste.
In the presented work, new...
Salophen modified biochar fibres derived from Luffa cylindrica sponges were prepared and subsequently studied as a potential U(VI) adsorbent by batch equilibrium experiments. The material was characterized before and after U(VI) adsorption by spectroscopic and microscopic methods of analysis. FTIR and SEM investigations revealed that the salophen modification of the biochar surface was...
Elemental and isotopic characterization of spent nuclear fuel is of crucial importance in nuclear reactor facilities for various purposes, including the management of spent nuclear fuel [1]. Characterization of spent nuclear fuel samples requires highly sensitive and precise mass spectrometric techniques, such as sector-field inductively coupled plasma-mass spectrometry (SF-ICP-MS) and...
The radionuclide lutetium-177 has become one of the preferred radionuclides for targeted therapy. The low tissue penetration of the emitted β- particles assures an efficient energy deposition on small size tumours (less than 3 mm) and a low radiation dose to the surrounding healthy tissue. This is especially useful when 177Lu is combined with different targeting molecules, which are...
Permeable reactive barriers (PRB) enable physical, chemical or biological in situ treatment of contaminated groundwater by bringing it into contact with reactive materials. The reactive material is inserted underground in a natural aquifer and intercepts the pollution plume as it is carried along within the aquifer. Thus the contaminants are treated with neither wholesale soil excavation nor...
The applicability of MnO2-resin for the selective separation of Ra(II) from aqueous solutions containing also U(VI) and Eu(III) has been investigated as a function of solution pH and salinity. The measurements were performed by LSC for radium and by spectrophotometry for uranium and europium, using Arsenazo-III. According to the experimental results the maximum chemical recovery of the...
The cold neutron beam guide of HANARO research reactor has a length of about 100 m and the cold neutron has a velocity of about 300 m / s. At this time, the cold neutrons are affected by gravity for about 0.333 seconds. In the Hanaro study, there is no history of measuring the influence of gravity and it is not reflected in the design. In this study, neutron beam images of the neutron energy...
The study of nuclear forensics can effectively deal with nuclear security incidents and potential nuclear terrorist threats, and prevent radioactive crimes or terrorist attacks. Through the analysis of the nuclear material of nuclear fuel cycle different stage, the initial source of nuclear material and the whole production process could be revealed. Due to the different geological conditions...
Increasing demand of high-purity and radiopharmaceutical grade radionuclides leads to the research and development of new, fast, simple and cost-effective separation methods. The most frequently used separation methods in nuclear medicine are liquid-liquid extraction or chromatographic methods. For example, the radionuclide 223Ra for targeted alpha-particle therapy is exclusively...
Ivanets A.I.1, Prozorovich V.G.1, Kouznetsova T.F.1, Radkevich A.V.2, Milutin V.V.3
1Institute of General and Inorganic Chemistry of the National Academy of Sciences of Belarus
2Joint Institute for Power and Nuclear Research – Sosny of the National Academy of Sciences of Belarus
3A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS
Ivanets@igic.bas-net.by
Currently, sorption...
In the Partitioning and Transmutation (P&T) technology, minor actinides burning to shorter-lived radionuclides can happen in Accelerator-Driven Transmuters (ADT) or in the GEN IV nuclear reactors. Among the fuel matrices considered to embed minor actinides for burning, inert matrices composed of molybdenum metal (CerMet fuel) or inert ceramic magnesium oxide matrix (CerCer fuel) are high on...
CeO2 solids of different surface areas have been prepared by sol-gel reverse micelles method using non ionic surfactant Triton X-100. The samples have then characterized by N2 isothermal adsorption, SEM microscopy and FTIR spectroscopy. The effect of the BET surface area/surface groups of the solids on the U(VI) adsorption has been investigated by batch-type experiments and evaluated by...
The present study shows the efficiency of various inorganic acids as shelf deposition solutions and their effects on nickel plates of 99% purity, 25 mm diameter and 0.50 mm of thickness [1]. 0.5M, 2M and 0.1M hydrochloric acid solutions in addition to 0.1M and 0.5M solutions of nitric, sulfuric, hydrofluoric and phosphoric acid were studied and compared.
Tap water was used as matrix,...
Adsorption of Th(IV) by Luffa Cylindrica sponges after controlled surface oxidation by nitric acid has been investigated by batch-type experiments as a function of various physicochemical parameters (e.g. adsorption capacity, pH, ionic strength, mass of the adsorbent, temperature and contact time). Fitting of the experimental results reveal that even under strong acidic conditions the relative...
Spent fuel is generated during power reactor operation in the form of spent fuel assemblies. Spent fuel assemblies are placed to at-reactor spent fuel pool for cooling, reducing of fission products radioactivity and radiation protection of staff. During storage of spent fuel assemblies radionuclides, both fission and activation origin, get to solution of spent fuel pool. Radionuclides,...
The Microtron MT 25 is a cyclic electron accelerator with a Kapitza type resonator. The accelerator is located in a laboratory belonging to the Nuclear Physics Institute of the CAS. The Microtron MT25 serves as a source of relativistic electrons (primary electron beam), secondary photon beams (bremsstrahlung) and neutrons from nuclear reactions. Photon beams are frequently used for...
Electronic interactions between metal and ligand are the origin of additional NMR chemical shifts observed on nuclei of the ligand in paramagnetic metal-organic complexes. The major two contributors to these paramagnetic chemical shifts are Fermi-contact shifts (FCS) and pseudo-contact shifts (PCS). FCS are due to delocalisation of unpaired electron density in molecular orbitals involving both...
Coordination Chemistry of Uranium (U(IV) and -(VI)) with Bidentate N-donor Ligands
Introduction
The bidentate N-donor ligands 2,2’-bipyridine (bipy) and 1,10-phenanthroline (phen) have attracted considerable attention in the field of coordination chemistry over the last decades because of their remarkable...
Alpha-hydroxycarboxylic acids are important molecules in nuclear field. They can be used as complexing agent or buffer in aqueous phase in actinide selective separation processes. These molecules are also present in the environment as a degradation product of cellulose. Therefore the alpha hydroxyl-carboxylate ligands are likely to influence the speciation in the fuel cycle processes and in...
The nuclear fuel cycle ends by spent fuel reposition in an appropriate facility. The long-term performance of a radioactive waste repository can be significantly influenced by geological, geochemical and also biological phenomena. Microbial processes may negatively affect canister (microbial corrosion) and buffer and backfill material (microbial induced chemical and mechanical changes) as well...
The bentonite materials are frequently designed as buffer/backfill material for engineered barrier in final disposal for spent nuclear fuels (SNFs) or high-level radioactive waste (HLW) repository. The clay minerals showed a favourable environment for sorption of Cs and Sr, bentonite having high sorption toward Cs and Sr were encapsulated in the biopolymer matrices (sodium alginate, NaALG) in...
A new type of heterocyclic “hard-and-soft” phosphinoxide-bearing N-heterocycles for f-elements binding was proposed from the basis of DFT simulation (PBE, B3LYP, cc-pVDZ and cc-pVTZ basis sets). The efficient method for the scalable preparation of the reagents by cross-coupling reactions was developed. As a N-donor scaffold the pyridine, 2,2’-bipyridine and phenanthroline were used and their...
99Tc is a long-lived (t1/2 = 2.1 x 105 years) β-emitter formed during the fission of U and is of major concern for radioactive waste disposal. Its environmental mobility is primarily governed by the oxidation states VII and IV, with TcVII forming the highly mobile TcO4− aquo anion, whereas TcIV is rather immobile due...
Introduction
Deep geological salt rock formations are in discussion to serve as host rock for a repository of high-level nuclear waste. This approach requires a well-founded knowledge of the geochemical behaviour of the radionuclides in diluted to concentrated salt solutions to model their potential migration and retention in the near- and far-field of the repository over long time scales....
Rare actinide isotopes are essential in many basic science research projects, yet working with them always features unique aspects, especially due to their limited availability and often high radioactivity. In our contribution, we will focus on actinide targets produced via molecular plating (MP) [1], a technique refined over decades and well-confirmed to be ideal in many cases. Recent...
Reliable long-term predictions about the safety of a potential nuclear waste repository must be based on a sound, molecular-level comprehension of the geochemical behavior of the radionuclides. Especially, their reactivity at the water/mineral interface will control their mobility and thus hazard potential.[1] A recent study has found a surprising dependency of the uptake of Th(IV) on the...
Contamination of the Baltic sea with radionuclides and potential risk to aquatic biota
G. Lujanienė1, B. Šilobritienė2, D. Tracevičienė1, S. Šemčuk1, V. Malejevas3
1SRI Center for Physical Sciences and Technology, Vilnius, Savanorių pr. 231, LT-02300, Lithuania
2 Ministry of Environment, A. Jaksto g. 4, LT-01105 Vilnius, Lithuania
3Marine Research Institute, Klaipėda University,...
Radionuclides, in particular actinides, can cause a serious health risk upon incorporation. Regarding the development of potential decontamination therapies, a detailed understanding of the different biochemical reactions of incorporated actinides is highly required. In the human body, actinides preferentially interact with blood serum components. One representative of utmost importance is...
An accident of Fukushima Dai-ichi Nuclear Power Plant (FNPP1) in March 2011 resulted in a large amount release of radiocesium (134Cs and 137Cs) into the North Pacific Ocean. Radiocesium deposited on and discharged directly into coastal area of Japan in the north of the Kuroshio Front had been transported eastward in surface layer and reached to the North American Continent by 2015 and early...
Aside to pure Physical Chemistry interest, determining uranium speciation is important for environmental monitoring or within experimental studies for possible remediation protocols (and possible application for prospection and extraction is of interest as well). Natural water samples dominated by system UO$_2{}^{2+}$ - CO$_3^{2-}$ - Ca$^{2+}$/Mg$^{2+}$ - H$_2$O have been chosen in this study....
We report for the first time an environmental uranium-236 (236U) and uranium-233 (233U) dataset, on samples in the Greenland marine environment during the 5-year period (2012-2016). Results are discussed in terms of time evolution and spatial distribution characters of radionuclides (236U) concentrations and isotopic ratios of 236U/238U and 233U/236U. Our results indicate that 236U...
Time-resolved laser-induced fluorescence spectroscopy is fast, easy and accurate optical method for low concentration determination and spectral characteristics of rare earth elements (e.g. Eu) and actinides (mainly U, Cm, Am) based on their luminescence properties.
Having Nd:YAG crystal as a laser source (emission wavelength 1064 nm) with the repetition frequency 10 Hz and Optical Parametric...
Abstract
Anthropogenic $^{129}$I release increased the $^{129}$I/$^{127}$I ratio by several orders of magnitude. In the 1960s, detonations of atmospheric nuclear weapons contributed to the $^{129}$I release; today the main sources are the reprocessing plants in La Hague and Sellafield. 90 % of $^{129}$I is released into the ocean, gaseous emissions account for only 10 %. Today, this...
Introduction
The complexation of actinides with different organic ligands is an important topic in terms of nuclear waste disposal. Depending on the host rock these molecules are either naturally occurring organic compounds as in pore waters of clay rock formations (e.g. acetate, lactate) or model compounds (e.g. oxalate, malonate, succinate) of organic macromolecules (polycarboxylate...
Protactinium, as a $^{235}U$ decay product, is naturally present in the environment as $^{231}Pa$ isotope (alpha emitter with a half-life of 32,400 years). Over the years, this isotope is accumulated in uranium tailings and stocks of yellow cake. Modelling the behavior of this element in the geosphere requires thermodynamic and structural data relevant to environmental conditions. The present...
239Pu (T1/2=24110 yr) and 240Pu (T1/2=6563 yr), because of their high chemical toxicity, long half-lives and high particle affinity, are not only good indicators for radioactive pollution but also useful geochemical tracers for better understanding a variety of marine processes. Pu isotopes have been intensively studied in the East China Sea to investigate their source terms, transport,...
In nuclear fuel reprocessing, after separation of uranium and plutonium using the PUREX process, minor actinides (americium and curium) are the main contributors to the long term radiotoxicity and heat load of the spent fuel. Therefore, new processes have been developed to separate americium and curium using polyaminocarboxylic acids as selective complexant. Due to the presence of radioactive...
Coumarins reaction ability with free radicals was studied. Antioxidant properties for coumarin, esculetin, esculin in reaction with carbon-centered hydroxyethyl radical, superoxide anion radical are shown. The influence of zinc ions on the change of coumarins reaction ability is investigated.
Minor actinides in used nuclear fuel are responsible for much of its radiotoxicity and heat generation. Actinide(An)/Lanthanide(Ln) separation processes via selective complexation and solvent extraction by designed soft S- and N-donor ligands can take advantage of the slight differences in relative hardness of An(III) vs. Ln(III), leading to potentially selective separations. Furthermore, the...
Due to the pollution of industrial effluents with toxic metals, often in ionic forms, and their spreading to the environment, much work is currently underway to develop the most efficient methods of separation of heavy metals (e.g. mercury, cadmium, chromium or arsenic) from aqueous solutions.
Arsenic is known for its very high toxicity. Its removal by conventional methods, aimed largely at...
Oxidative embrittlement (voloxidation, volume oxidation) of both the fuel itself and of Zircaloy fuel claddings shows promise as modification of head-end operations of the PUREX process. The gas-phase conversion of oxide fuel in various atmospheres (O2, air, О3, Н2О vapor, air–СО2 mixture) at 300–600°С ensures almost complete removal of volatile components (3H, 14C, 129I, radioactive noble...
We have observed the formation of OH radicals in aqueous solutions under the effect of 253.7 nm (4.89 eV) UV radiation delivered from a low-pressure Hg-lamp [1]. By combination of chemical actinometry (iodide-iodate system) with the tools conventionally used for the characterization of radical yields during radiolysis of aqueous solutions (a fluorescence dosimeter - coumarin-3-carboxylic acid...
The uranium hexafluoride depleted in the U-235 isotope (DUHF) is a by-product of isotope uranium enrichment in the nuclear fuel cycle (NFC). The accumulated DUHF amount in the world reaches 2 million tons, including in Russia up to 1 million tons.
Uranium hexafluoride is a very toxic substance (maximum allowable concentration in the air is 0.015 mg•m-3), volatile (p = 0.1 MPa at 56 °C) and...
The prostate-specific membrane antigen (PSMA) has emerged as an attractive target for imaging and therapy of prostate cancer. Despite many advances in the past years, the treatment of metastatic castration-resistant prostate cancer (mCRPC) still remains challenging. The aim of this study was to optimize radionuclide therapy of mCRPC through the development of albumin-binding PSMA ligands with...
Human nuclear activity has produced a large amount of radionuclides, some of them was released to the environment, while most of them are remained in various radioactive waste to be deposited. Among these radionuclides, long-lived radionuclides such as 14C, 36Cl, 79Se, 99Tc, 126Sn, 236U, 237Np, and isotopes plutonium, neptunium, americium and curium are most important in view of waste...
Airborne radioactive iodine is a key concern for transport and dispersion of radioactive contamination and radiation exposure evaluation during nuclear accidents and nuclear emergency preparedness. Long-lived 129I in aerosols is vital for reconstruction of level and distribution of short-lived and highly toxic 131I, as well as understanding the knowledge of atmospheric circulation process of...
Monocarboxylate transporter 1 (MCT1) is an integral plasma membrane protein that bi-directionally transports lactate and ketone bodies and is highly expressed in non-hypoxic regions of human colon, brain, breast, lung and other tumors. Accordingly, MCT1 inhibitors are regarded to be of potential clinical use. In the current study we developed a new 18F-labeled radioligand for in vivo imaging...
Alpha radionuclide therapy (ART) is a very powerful tool for the treatment of small tumour metastases. Due to their short range and high LET, alpha particles are much more efficient at killing cells than the commonly used beta radiation. Furthermore, their short range stops them from destroying neighbouring healthy cells. One of the main problems which still needs to be solved before ART can...
An important characteristic of spent nuclear fuel is its burnup, which is a measure of fissionable material consumption prior to fuel replacement. Isolation of lanthanides, most importantly neodymium, from spent nuclear fuel is necessary to determine the burnup experimentally. As an introduction, various ion chromatographic strategies for lanthanide isolation described in literature will be...
The radionuclides employed in targeted alpha therapy are often actinides (e.g. 225Ac, 227Th) with multiple radioactive daughters. Successful treatment relies on the radiopharmaceutical’s ability to “hold-on” to 225Ac (or 227Th) while it is delivered to the target cancer cell. Imaging surrogates of the radiopharmaceutical permit non-invasive pharmacokinetic assays and enable rapid screening of...
Introduction: 119Sb is one of the most potent radionuclides for Targeted Auger Therapy due to convenient energy and numbers of Auger electrons as well absence of any other accompanying emissions [1-3]. Antimony-119 has a half-life of 38.5 hours which is well suited for radiotherapeutic application. In the present work: production, radiochemical separation and chelation preference of...
Abstract:
Anthropogenic 129I on surface environment mainly originates from three sources, including nuclear weapon tests, nuclear fuel reprocessing plants, nuclear accidents, with different pathway. This leads to 129I deposition history recorded in sediment is not the same in different regions. Due to its long half-life and high conservative feature in the ocean，129I has been used as an...
The plutonium isotopes, 239Pu and 240Pu, have been added to the surface oceans mainly as a consequence of global fallout from atmospheric nuclear weapons testing. There were two major sources of Pu isotope in seawater in the western North Pacific Ocean: global (stratospheric) fallout which occurred mainly in the late 1950s and early 1960s, and local fallout from the Pacific Proving Grounds...
Geological reference material is essential for analytical research and has been widely used for a chemical analysis to obtain accurate geochemical data. Also, it is useful to evaluate the accuracy and precision of the analysis, to develop and improve analytical techniques. Although there is a trend that demand for these geological reference materials is increasing but development of Korean...
For the irradiations, 40 mµ thick tantalum foils were used that have been annealed after being rolled and labelled with 57Co. Diffusion impingement of evaporated radioactive atoms onto the surface of tantalum substrates was carried out for 140 minutes at 1270-1275 К (E-7 Torr) that was followed by cooling both the foils and the furnace down to the ambient temperature.
Irradiation conditions...
Contamination of the aboveground parts of plants caused by root uptake and dust particles sedimentation on a surface of plant organs above the ground. The overall aim of the work is evaluate of foliar uptake of radionuclides in plants groves in areas with a high contamination density of soil by the radionuclides.
The studies were performed at the territory of Polessky State Radiation and...
The discovery of long-lived isotopes of superheavy elements (SHEs) in nuclear fusion reactions of $\rm ^{48}Ca$ with actinide targets signifies a close approach to the island of particularly shell-stabilized nuclei. While the emergence of the new elements is a fantastic discovery itself, the longevity of certain isotopes is thought-provoking for chemical investigations, both experimental and...
On March 11, 2011, the Tohoku earthquake and the subsequent series of tsunamis severely damaged the Fukushima Dai-ichi nuclear power plants (FDNPPs). Failure of cooling systems led to explosions releasing radioactive gas and debris to the atmosphere along with cooling water that was directly discharged to the sea after being in contact with the nuclear fuel. The resulting release of 90Sr (T1/2...
Colloids existing in soils and groundwater aquifers can facilitate the transport of environmental contaminants including radionuclides as well as hydrophobic organic compounds. The mobility of colloids depends strongly on dispersion and aggregation of the particles. Therefore, the environmental fate and stability of colloidal bentonite particles under various conditions are crucial for...
Application of radioactive and stable isotopes to trace organic matter in the Baltic Sea
G. Lujanienė1, P.P. Povinec2, H.-C. Li3, K. Jokšas4, J. Mažeika4, N. Remeikaitė-Nikienė1,5, V. Malejevas1,6, G. Garnaga-Budrė5, L. Levinskaitė4, S. Šemčuk1, I. Kulakauskaitė1, R. Barisevičiūtė1, D. Bugailiškytė1, A. Stankevičius1,5
1SRI Center for Physical Sciences and Technology, Vilnius,...
The work presents data on the aerobic and anaerobic microbiological processes impact on Uranium migration in upper aquifers polluted with sulfate and nitrate ions near to sludge depository of Novosibirsk chemical concentrate plant. Sludge depository was built in 1960s and still works. Uranium concentration in subsurface water reaches in several zones 1-2 mg/L and its migration depends on some...
In recent years, the precision achieved in resonant ionization spectroscopy experiments coupled with advances in atomic theory has enabled new atomic physics based tests of nuclear models. The measurements of hyperfine constants and isotope shifts are highly sensitive to the changes of the nuclear charge and magnetic radii because they depend on the behavior of the electron wave function near...
Over the past decade, the scientific community involved in the research and development of therapeutic radiopharmaceuticals (RPhs), has been taking growing interest in the isotope of the rare-earth element, Lu. 177Lu radionuclide (T1/2 = 6.65 days) exerts the properties of a “soft” β—emitter (Eβmax = 498 keV), which makes it convenient for treatment of small malignant formations (the maximum...
Exposure to alpha, beta or gamma radiations from natural sources, which is varies by location and altitude, affect the living organism. The main sources are earth crust (83%) and cosmic (17), with annual exposure 2.0 mSv and 0.4 mSv, respectively. The objective of this study is to identify the radionuclide concentration in certain cities (Riyadh , Hagl and Khafji), of Saudi Arabia. The...
Traces of radioactive isotopes of ruthenium in the atmosphere were reported in the beginning of October 2017 by several European stations monitoring the airborne concentrations of gamma emitters (e.g., IRSN, 2017). As of February 2018, the source in Eastern Europe has not been publically identified. $^{106}$Ru is a fission product with a half-life of 371.5 days. It is used as a medical isotope...
At the very end of September and in October 2017 artificial radioactive isotope Ruthenium-106 has been detected in air over Europe. It was primarily found in Northern Italy and Central Europe. $^{106}$Ru was detected by means of aerosol sampling stations used in continuous monitoring of presence of radioactive isotopes in ground-level air. In Krakow, $^{106}$Ru was firstly detected on filter...
Chemical studies of the heaviest elements provide crucial and challenging opportunities not only to advance our understanding of properties of matter at the limits of existence but also those to elucidate the influence of relativistic effects on atomic electrons and to architect the periodic table of the elements at the farthest reach [1,2]. The influence of relativistic effects on electronic...
Radon is a rare gas element which has only radioactive isotopes. It is supposed to be an important and useful element because we could find anywhere on the earth and we might utilize for medical use in cancer therapy.
There are several measurements available such as an ionization chamber measurement and a track counter method. We can also measure the radon concentration in solution by using...
In the present study, the carboxymethyl cellulose (CMC) hydrogel containing activated carbon-silver nanoparticles (Ag NPs) composites (Acc-Ag composites) was fabricated for the highly functional wound-dressings by electron beam irradiation. For this, the Acc-Ag composites were first prepared using a thermal treatment under an inert argon (Ar) atmosphere. During the thermal treatment, the Ag...
Black liquor is biomass-based industrial waste obtained from the chemical pulping process of wood. The lignocellulosic materials such as lignin, hemicellulose and other extractives are dissolved into black liquor. Lignin, which can also be extracted from black liquor, exhibits good thermal stability and high carbon yield. In the present study, compared to the lignin obtained by a lab-scale...
At the ELI Beamlines facility the first endstations dedicated to user experiments that are starting just now are those of the team fulfilling the Research Program 4: Applications in Molecular, Biomedical and Material Science. The endstations will utilize optical, extreme UV and plasma X-ray beams to perform pump-probe experiments on diverse sets of samples (free atoms, molecules and their...
TeaM Cables is a European collaborative Research and Innovation project focusing on nuclear cable ageing.It has received 4.2 M€ of funding from the Horizon 2020 Euratom Research and Training Programme of the European Union. TeaM Cables started in September 2017 for a duration of 4.5 years.
TeaM Cables aims at providing NPP operators with a novel methodology for efficient and reliable NPP...
Air and food are the main sources of many chemical elements, also natural and artificial radionuclides transferred to human organisms. The intensity of radioisotopes intake depends on the place of residence, local radiation quantity, diet habits and food origin. So far, during annual radiation doses evaluations in Poland, the most often consumed food products were taken into account. Among...
This work represents a part of the research dealing with the study of properties of homologues of SHE. The aim of the experiments was to test the possibility of the separation of thallium from indium as the homologues of nihonium using the ionic liquids as the organic phase. Short-lived thallium and indium isotopes were generated by irradiation of Au and Ag target foil on U120M cyclotron at...
Dressings for human wounds have been aimed at protection, removal of exudate, inhibition of exogenous microorganism invasion, and improved appearance. Protection was accomplished by covering the wound with dressing materials. Wound areas that are kept just damp may heal faster, but accumulation of exudates under the dressing can cause infection. Silver is important in the treatment of wounds...
After the Fukushima Daiichi Nuclear Power Plant (FNPP) accident in March 2011, a huge amount of radioactive cesium was released over a widespread area in eastern Japan. People were seriously concerned about food safety. Therefore, the Ministry of Health, Labor and Welfare established a provisional regulatory value of 500 Bq/kg for radiocesium in cereals, vegetables, meat, and fishery products....
The practice of liquid radioactive waste (LRW) injection in deep stagnant aquifers in Russia dates back to 1963 year. The safety assessment and safe operation of existing LRW repositories require complex modeling of basic geochemical processes. Sorption onto mineral phases tends to be the main process affecting the dynamics of migration of radioactive and other contaminants in geological...
Liquid extraction is widely used in radiochemistry for the concentration and separation of elements. When the organic phase containing the extragent contacts with the aqueous phase in which contains element the reactions occur in the interfacial layer. As a result of the reactions, several compounds are formed, among which there are often those that do not directly pass into either the organic...
Crystalline rock is suitable the safety disposal of high-level radioactive waste (HLW). Fracture networks connections can dominate flow behaviors at the crystalline rock. In this study, advection-dispersion column experiments of cesium (Cs) through crushed granite (0.297 - 0.840 mm) were constructed where synthetic groundwater (GW) and seawater (SW) were employed as the liquid phase. This study...
The release of uranium from mine tailings may present a hazard to the environment, which is the reason for the monitoring of the relevant storage sites in many countries. Studying the behavior of released radionuclides at these sites serves to better estimate the local risk and can help to improve the understanding of the geochemistry of the involved contaminants, e.g. for the application in...
Polonium 210Po and radiolead 210Pb belong to the uranium series decay chain with half-lives of 138.376 days and 22.2 years respectively. They are relatively toxic to humans, especially α-emitting 210Po, both chemically and radiologically, and are accumulated to a considerable extent. The main sources of chemical elements intake are air and food but their intensities depend on living place,...
Accurately determined uranium isotope ratios are essential for geochronological dating and tracing of different environmental processes. In addition, they are of paramount importance for nuclear safeguards and nuclear forensics.
Multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has become an important tool for determination of uranium isotope ratios in both liquid and...
The influence of ionizing radiation on living cells’ radiation sensitivity can be affected by many parameters like dose rate, temperature, level of oxygen in irradiated system or presence of some chemicals (radioprotectors or radiosensitizers). Radioprotectors can reduce radiation sensitivity of living cells to ionizing radiation due to their high reactivity with hydroxyl radicals produced...
Barra de Valizas – Aguas Dulces area is placed in the strip coast of the 290 Ramsar site, located in the eastern region of Uruguay, on its Atlantic coast. The studied area included two coastal towns and a freshwater lagoon.
The activity concentration of 238-U, 226-Ra, 210-Pb, 232-Th, 40-K and 137-Cs radionuclides in sand, soil and Baccharis articulata were evaluated. For the quantification...
The Iberian Pyrite Belt (South of Spain) is plenty of acid pit lakes as a result of former mining. These pit lakes are leaching some limited amounts of acid water into their close environment: acid mining drainages (AMD). But in 2017, an accident occurred in an abandoned mine called “La Zarza” and from the associated pit lake approximately 250,000 m3 of acid water were discharged into a small...
Artificial radionuclides and, first of all, the most dangerous isotopes of transuranium elements(TUE) became constant and irreversible components of the biosphere because of the experimental nuclear explosions performed, the wrong concept of the disposal of radioactive wastes to open water reservoirs, and also process upsets and emergency situations at NFC enterprises .
It is known that many...
The interest in interaction of actinide “yl” cations with anions of heterocyclic carboxylic acids appreciably increased recently, which is caused by a number of factors. In particular, it became clear that the coordination behavior in the series of hexavalent (U, Np, Pu) and pentavalent (Np, Pu, Am) actinides in some systems significantly varies. For more detailed study of the coordination...
Carboxylic acids of different composition are the most frequently encountered components of a variety of natural media. They are active complexing agents for actinide ions in higher oxidation states and sometimes, depending on actinide ion pare redox potential, can play reductant role. Taking into account that actinide elements in higher oxidation states have an increased solubility in the...
The first synthesis of a superheavy carbonyl, seaborgium hexacarbonyl, has witnessed the step of the studies on superheavy element chemistry into a new era. The carbonyl complexes of element 107 (bohrium) and 108 (hassium) are the next targets for the investigation. In “few-atom chemistry” condition, the structures, properties and stabilities of bohrium carbonyls are influenced by both the...
The chemical investigation of molecular transactinide species is still a challenging task mainly due to the low production cross sections and short half-lives of all superheavy (SHE) isotopes available so far. Despite those challenges, there is currently a lot of effort going on in this field as it promises a wealth of insights into relativistic effects, into the structure of the periodic...
Some aquatic ecosystems from Mexico, such as rivers and lagoons, are affected by wastes enriched with potentially toxic elements generated by precious metal mining activities. Contamination of water, sediment and affected biota has produced several environmental issues, including biological effects in some species of flora. On the other hand, mineral processing activities may also generate...
Results for, Cs-137, Pu and Th isotopes activity concentration found in the upper part of bottom sediments taken from a deep part of 29 lakes on Mazurian Lakes area (North-Eastern Poland). Samples were collected by diving. Results for 137Cs were obtained using low background gamma ray spectrometry, Pu-238, Pu-239+240, Th-230 and Th-232 were obtained by means of alpha spectrometry and those...
Polonium is a radioactive element present in many components of the marine and terrestrial environment. $^{210}Po$, the most abundant naturally occurring radioisotope of polonium, is one of the descendants of the uranium ($^{238}U$) decay series. Rocks, soil, water, sediment, and biota, contain traces of $^{210}Po$ in variable amounts. $^{210}Po$ may be radiotoxic to humans and non-human biota...
This study aimed to assess potential radiotoxicity to human consumers from 210Po and 210Pb accumulated in several species of mushrooms from the family Boletaceae that are traditionally collected in Poland and China. Fruitbodies of B. edulis were from the Yunnan province of China and from the northern part of Poland, and individuals of pine bolete Boletus pinophilus, summer cep Boletus...
Radiation- and photo-induced precipitation was used for the synthesis of nanopowder scintillators based on ZnO:Ga. It is very efficient method published rarely outside of our research group. In principle, an aqueous solution of precursors (in the case of ZnO usually zinc nitrate or formate, a scavenger of OH radicals and/or hydrogen peroxide) is irradiated by non-ionizing (UV) or ionizing (γ,...
Nuclear medicine involves the administration of I-131 to patients in order to treat or diagnose thyroid lesions. Commonly, it is administered orally in a liquid or capsule form. Once this radioisotope enters into the patient’s body, it is mainly excreted via urine and in this way it can reach wastewater treatment plants (WWTP) [1]. Consequently, radioiodine can be present in the different...
The aim is this work is to establish if the presence of a solid surface, like a clay mineral, during the irradiation of adenine (purine bases) alter the stability, formation, and distribution of radiolytic products in comparison with samples of those molecules without the mineral. The results showed that these bases could receive higher irradiation doses with less decomposition to the samples...
Chemical evolution encompasses the formation of biologically relevant compounds started from simple inorganic molecules and promoted by an energy input. Among the possible energy sources for these processes is radioactivity. This research is done in this framework, and it is aimed to study the effect of ionizing radiation on oxygen-free, aqueous solutions of ammonium succinate. Particularity...
An investigation was carried out on the acid drainage (pH 3.96) of an old uranium mine (Quinta do Bispo mine, Portugal), containing activity concentrations of 61000±7300 mBq/L of 238U, 886±60 mBq/L of 226Ra and 504±27 mBq/L of 210Po, and relatively high mass concentrations of Ni, Al, Fe, Mn, and Zn. This mine water is treated with addition of BaCl2 and pH increase with addition of hydroxide,...
The aerosol particles accumulated during winter in the snow cover of the Novosibirsk vicinity are studied by the means of the gamma-ray spectrometry, ICP-MS, X-ray fluorescent analytical methods. These studies allowed revealing the contribution of separate industrial enterprises into the general technogenic pollution of the megapolis with uranium and thorium.
The work was supported by the...
One of the major pollutants in nuclear waste is 99Tc, a redox-sensitive fission product from 235U and 239Pu with a long half-life of 2.14 X 10 5 years. Under environmental oxidizing conditions, 99Tc mainly exists in aqueous solution as pertechnetate, TcO4-, which is a highly water-soluble ion that does not sorb...
Human lung ashes were collected in Vienna, Austria, during the early sixties of the last century in order to determine short-lived fission products from the nuclear test explosions by gamma-spectrometry (1). Later on in part of these samples also plutonium was determined by alpha-spectrometry (2).
Last year we started to investigate some of the remaining samples with regard to 236U (half-...
Key words : Self-diffusion (coefficients)/ Solvation / Actinide/ Lanthanide / Trivalent (aqueous ions )/ Hydolysis.
Abstract:
In this paper, we present a realistic model for estimation of trivalent actinides and lanthanides ions self-diffusion coefficients. We take account hydrolysis phenomena. We use Fuoss theory and Bjerrum approach to calculate Kh the thermodynamic hydrolysis constant. We...
Radio-tellurium isotopes such as Te-127m and Te-129m were released into the environment as a result of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. A large amount of Te-127m and Te-129m was released, and these isotopes have relatively long half-lives (109 and 33.6 days, respectively). As such, ingesting food harvested from the contaminated area shortly after the accident could...
Early we studied the sorption of microamounts of 60Co2+, 85,90Sr2+, 90Y3+, 131I–, 131IO3–, 137Cs+, and 233,238U(IV) onto layered double hydroxides (LDHs) of Mg, Cu, Al, and Nd, containing various anions in the interlayer space, and also onto layered double oxide (LDO) of Mg and Al, prepared by thermal decomposition of the corresponding LDH. It was found that LDH-Mg-Al-Anion (Anion = CO32–,...
Within the DGR project in the Czech Republic, the local Mg/Ca bentonite named BaM (Bentonite and Montmorillonite) has been tested with the aim to assess its sorption qualities with regard to cations necessary for the performance assessment of the repository.Sorption batch experiments present a tool to estimation of sorption coefficients which provide useful information on the transport...
Layered double hydroxides (LDHs) belonging to two-dimensional supramolecular systems are compounds of the composition [(M2+)1–x(M3+)x(OH)2]•[(An–)x/n•mH2O], where М2+ and М3+ are cations in oxidation states 2+ and 3+, respectively; An– is practically any anion or anionic complex. An advantage of LDHs over other layered compounds is the fact that various anions can be intercalated in their...
Ground water pollution by long living radionuclides can cause their introduction into subsurface environment and drinking water sources. Such actinides as uranium, neptunium, plutonium, americium and technetium as fission product are ones of the most important radionuclides in radioecological management because of their toxicity and long living. Their migration ability in environment depends...
Sputtering of actinide targets, Ti target backing and window foils irradiated by intense heavy ion (HI) beams in long-term experiments has been considered on the grounds of available models and experimental data. Experiments on synthesis of superheavy nuclei (SHN), which are carried out with the Dubna Gas-Filled Recoil Separator (DGFRS), are the examples of such kind of experiments. High...
In most of the cases interaction between uranyl ions UO22+ and anions of aliphatic monocarboxylic acids L leads to formation of mononuclear anionic complex units [UO2L3]–. Crystal structures of corresponding compounds are usually three-dimensional due to electrostatic interactions or hydrogen bonding among the complex ions [UO2L3]– and different counter ions. Such compounds have long been...
One of the most important tasks of the nuclear industry is to develop effective liquid radioactive waste treatment technologies with the aim to minimize their amount and immobilizу for future safe storage. Various sorption materials are used to extract radionuclides from aqueous solutions. The products of oil shale processing can be the promising sorbents, as their mineral components are...
There is only one stable cesium isotope with a mass number of 133 in nature. However, an artificial radioactive cesium isotope - cesium-137 is the most radiationally hazardous and practically important. Its main source is the fission reaction of uranium nuclei. The efficacy of separation of 137Cs from nuclear waste depends on the chemical and structural compatibility of uranium (VI)...
Method of synthesis of the REE hexauranates is proposed in this work. The composition and structure of these compounds were defined, processes of dehydration and thermal decomposition were studied, the state in aqueous solutions was investigated by X-ray fluorescence spectrometry, chemical analysis, IR spectroscopy, high-temperature X-ray diffraction and thermography. The choice of MIII (MIII...
THE ADSORPTIVE BEHAVIOUR OF HEAVY METALS ON MAGNETIC NANO-SORBENTS
I.Kulakauskaitė, G. Lujanienė, D. Valiulis
Center for physical sciences and technology, Savanorių ave. 231, LT-02300 Vilnius, Lithuania
ieva.kulakauskaite@gmailcom
Currently, water is one of the most vital human resources and is of the economic, social, political and environmental importance throughout the world. With the...
Forecast of engineering barriers evolution is an important problem of radioecology.
The goal of the following study is the development of complex methodology of modeling different processes, occurring during evolution of multibarrier system, and creating a uniform approach to safety analysis.
Methods of the description of the major factors, important for modeling multibarrier system (thermal...
Cerium dioxide is known as a non-radioactive structural substitute of actinide oxides (UO2 and PuO2). CeO2-based ceramics is suggested as an inert 239Pu or 235U bearing matrix for nuclear fuel, as well as a matrix for high-level waste disposal. CeO2 is also used an exhaust gas afterburning catalysts and in electronics.
X-ray photoelectron spectral structure of CeO2 valence electrons in the...
The objectives of this research were to investigate the naturally occurring 234U and 238U in calcium and magnesium supplements, find the correlations between 234U and 238U concentration in medicament and its chemical form, as well as calculate the effective radiation dose connected to analyzed supplement consumption. The analyzed Ca and Mg pharmaceutics contained their organic or inorganic...
Research in the field of superheavy elements (SHE) has gained quite a significant progress with introduction of doubly magic 48Ca beams into the experimental campaigns aimed to reach the shores of the island of stability [1]. As known cross-sections of reactions, leading to SHE is limited to pico-barns thus requiring high beam intensities (now available within an order of magnitude...
Cerium dioxide, CeO2, is a fluorite structure ceramic widely used as an inactive structural surrogate to UO2 and PuO2 to avoid difficulties associated when working with radioactive materials. This material is suggested to be used as an inert matrix for perspective nuclear fuels and highly radioactive waste disposal. Irradiation studies, where CeO2 is exposed to ions with different mass and...
Enhanced environmental radioactivity was reported for some spots of the Kabul suburbs
during the Soviet era. As residential houses have been built in these places, 51 soil and
rock samples as well as 51 all-purpose water samples were collected in three phases and
measured in order to quantify the primordial isotopes and daughter nuclides of the respective
decay chains and possible...
Theranostic medicine is a new integrated therapeutic system which can diagnose, deliver targeted therapy and monitor the response to therapy. Many of the “neutron rich” radionuclides that emit both imaging photons as well as therapeutic beta particles and which would be potentially excellent choices for metabolic radiotherapy and theranostic applications are produced by nuclear reactor with a...
Biogeochemical factors of Uranium and Technetium migration in subsurface water near to RW repository
A. Safonov1, R. Aldabaev1, N. Andryushchenko1, K. Boldyrev2, T. Babich3, K. German1, E. Zakharova1, A. Novikov4
1A.N. Frumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences
2. The Nuclear Safety Institute (IBRAE) Russian Academy of Sciences
3. Research...
The interaction between groundwater and surface water was important to know groundwater recharge process of the artificial recharge system. To understand recharge process, natural isotopes such as 222Rn and 87Sr/86Sr ratio variation were used. And also these tracers used to identify groundwater mixing phenomena for the artificial groundwater recharge of the water curtain greenhouse system. The...
Diagnostic imaging using $^{99m}$Tc ($T_{1/2}$ = 6.0 h), which is produced from the decay of $^{99}$Mo ($T_{1/2}$ = 66 h), is relying on the production of $^{99}$Mo from nuclear reactors to be shutdown. Alternative routes to produce the $^{99}$Mo and $^{99m}$Tc isotopes are being investigated. One of the reactions to create $^{99}$Mo is the $^{96}$Zr($\alpha$,n)$^{99}$Mo reaction. There are...
Environmental and rare nuclear physics experiments require operation of Ge spectrometers in deep underground laboratories. Cosmic-ray background of Ge gamma-spectrometers is decreased to such low-levels that observation of cosmogenic radionuclides produced e.g. in germanium (${}^{68}$Ge, ${}^{60}$Co, ${}^{65}$Zn, ${}^{54}$Mn) and copper (${}^{54}$Mn, ${}^{57}$Co, ${}^{60}$Co, ${}^{58}$Co) is...
99mTc is very important for medical practice, and efforts to develop the best procedure for the production of its parent 99Mo for the subsequent use in 99mTc generators are being made for more than four decades. For this purpose, a composite ceramic target containing HEU dioxide and a filler metallic powder (Al, Mg, etc.) has been irradiated in a high-flux reactor to obtain concentrate...
Backgrounds induced by neutrons and gamma-rays are important background components for all experiments looking for rare events, such as dark matter interactions or neutrinoless ββ decay. Neutrons and gamma-rays can be produced by natural radioactivity, via spontaneous fission or (α, n) reactions and by interactions of cosmic rays. Predicting all background components correctly is crucial for...
Theranostics, which combines therapy and diagnosis, is one of hot topics in nuclear medicine. Theranostic RI to provide such new medical treatment have been investigated. We focus on $^{177}$Lu (T$_{1/2}$ = 6.6 d), which is one of candidates of theranostic RI since it emits both beta particles and gamma-rays, which are suitable for therapy and diagnosis, respectively. However, the production...
Accelerator mass spectrometry, inductively coupled plasma mass spectrometry, neutron activation analysis and underground gamma-ray spectrometry have been investigated for ultra-sensitive analysis of long-lived radionuclides ($^{238}U$ and $^{232}Th$) in isotope sources and in construction materials designed for underground studies of rare nuclear processes and decays. Specific features of each...
In order to maintain European nuclear operations, expertise in nuclear and radiochemistry (NRC) is of strategic relevance. NRC contains key knowledge and techniques needed by a modern society and is certainly needed in addressing many societal challenges.1 The MEET-CINCH project is the third CINCH-based project aiming on cooperation in education in nuclear chemistry and radiochemistry. In the...
The main objective of the CORONA Academy is to enhance the safety of nuclear installations through further improvement of the training capabilities aimed at building up the necessary personnel competencies. CORONA II project is an international project funded by the EC which has all its support to achieve a real and effective implementation. Specific objective of the proposed CORONA II project...
Significant improvements in construction of Ge detectors for ultra-sensitive gamma-ray spectrometry systems located underground have been made in recent years. A special attention in the construction of the spectrometer was paid on requirement to achieve as low as possible background rates at the lines of progenies in the decay chains of U-238 and Th-232. Radiopurity of construction materials...
INTRODUCTION
The lack of trained nuclear chemical specialists has been identified in all branches of nuclear industry and other areas where skills in NRC are required, such as radiopharmacy, nuclear medicine, radiation protection and radioecology, and many others. Retraining general chemistry graduates is one of the options for mitigating this problem. Hands-on Training in Nuclear Chemistry...
Carbon-based nanomaterials (nanocarbons) exhibit exceptional mechanical, electrical, thermal, and optical properties. These materials are attractive in various fields of science and technology, including energy storage. Despite the interest in nanocarbons as electrodes for supercapacitors and batteries, additional elements present at variable quantities could influence their electrochemical...
This book is the second edition of Nuclear and Radiochemistry first published in 2012 and aims to provide the reader with a detailed description of the basic principles and applications of nuclear and radiochemistry. Its content is based on the authors’ more than 50 and 25 years of experience, respectively, as professors of nuclear and radiochemistry at both the B.Sc. and M.Sc. levels in the...
Plutonium and americium belong to anthropogenic elements, and these ultra-trace elements are detected from environmental samples. Origin of these elements comes from the nuclear bomb tests and the accidental release from nuclear power plants. Isotope ratio and elemental abundance of these actinides provide information on the source term and the elapsed time [1][2]. Uranium and thorium in...
Elemental speciation of As, Se and Fe in infant formulas is of prime importance in order to identify the sources of the specific chemical forms of trace elements. It enables to get better information about their metabolic pathways. In the case of As, it was found, that dietary exposure to inorganic As for children under 3 years old (including rice based food) is estimated to be about 2 to 3...
The European Network on Nuclear and Radiochemistry (NRC) Education and Training [1] is a non-profit cooperative platform of mainly, but not exclusively, European universities, research organizations and national research centers providing NRC education and training. Also industrial partners and end-users either conducting training themselves or having need for respective training courses for...
Radioactive wastes with elevated natural radionuclides content, like wastes from uranium ore processing, can be deposited relatively close to agricultural areas. It is therefore important to understand the behavior and transport of those radionuclides in the environment. In support to this knowledge, a plant pot experiment was carried out, involving three different types of vegetables (radish,...
After the Fukushima nuclear power plant accident, radionuclides containing fission products were released from the fuel debris into the cooling water. For the treatment of the contaminated cooling water, the Advanced Liquid Processing System (ALPS) facility has been operating for 7 years. Most of the cationic species of fission products are well eliminated in ALPS by sorption and/or...
Experimental research on active materials often goes along with the generation of compositionally complex waste streams for which a suitable route towards safe (interim) storage is lacking. This has worldwide resulted in the accumulation of significant volumes of highly diverse types of waste. The complexity of the streams invokes the need for tailored solutions for the individual components....
The final disposal of spent nuclear fuel will be performed in Finland in a geological repository in crystalline granitic rock at a depth of 400 meters [1]. The processes affecting the transport of radionuclides from the spent nuclear fuel to the biosphere need to be carefully taken into account when considering the overall long-term safety of the repository [2]. Consequently, it is necessary...
Radiocesium is a major radionuclide discharged into the environment as a result of the Fukushima Daiichi Nuclear Power Plant accident. Because radiocesium isotopes have relatively long physical half-lives (134Cs: 2.065 years; 137Cs: 30.04 years), they are the most significant long-term radioactive contaminants in the environment. When radiocesium is deposited on solid ground, it remains in the...
Various mushroom samples, lichens and pteridophytes are collected nationwide in 2017 and their contents of artificial radionuclides (137Cs, 238Pu, 239,240Pu and 90Sr) are measured to address the growing concerns regarding the radioactive contamination of food products in Korea.
The analysis shows that the activity concentrations of 137Cs range from minimum detectable activity (MDA) to 77...
Several laboratory through-diffusion experiments with HTO, 36Cl, selenate, 22Na, 85Sr, 134Cs, and 133Ba were performed on samples from experimental and monitoring borehole of the Long Term Diffusion Phase III experiment in Grimsel Test Site. Salinity dependent cation excess and anion exclusion effects were observed. Anion effective...
Crystalline rocks are being considered as potential host rocks for the construction of deep geological repositories (DGR) for radioactive waste in a number of European countries including the Czech Republic. The aim of the project (PAMIRE) was to determine the degree of reproducibility the laboratory determination of tracer transport processes of the tracers compared to the results of the the...
The Waste Isolation Pilot Plant (WIPP) is a radioactive waste repository operated by the U.S. Department of Energy (DOE) for the permanent disposal of defense transuranic (TRU) and TRU-mixed wastes (wastes that also have hazardous chemical components). Located near Carlsbad, New Mexico, the WIPP facility is the world’s first deep geological disposal facility licensed to accept TRU waste...
A novel method based on the retention and sequential elution of all actinides on a single small DGA resin® column has been developed and published recently1. DGA resin® is an actinide selective extraction chromatographic material which contains N,N,N’,N’-tetraoctyldiglycol-amide sorbed onto Amberchrom CG-71 inert support (developed by Horwitz et al.2 , available from Triskem International)....
Silica-based materials offer the opportunity for “selective decoration” where a large variety of adduct, ion exchange and chelate forming organic ligands can be attached directly to the surface. With the correct choice of ligand, in combination with high surface functionalisation, it is possible to offer high sorption capacity, fast exchange kinetics and selectivity for a variety of metal...
Introduction
An exercise for emergency situations was held in the Austrian Agency for Health and Food Safety in cooperation with the federal state Carinthia. The Exercise was funded by the Federal Ministry of Sustainability and Tourism. Therefore 21 soil samples, 19 ground vegetation samples and 6 sediment samples were collected. During former emergency exercises samples were only measured...
Some nuclear accidents and nuclear fuel treatment (such as reprocessing) can release radioactive iodine isotopes, principally 129I and 131I, into gaseous streams and aqueous solutions. Iodine-131 raises concerns in nuclear accidents due to its high activity and the potential for uptake into the human body but does not pose a long-term disposal risk due to its short half-life (t1/2 = 8.04 d)....
Molybdenum is an alloying component of structural materials used in nuclear reactors. The activation product of stable Mo-92 (14.65% abundance) is Mo-93, which has a long half-life ((4.0±0.8)×10^3 years); so it is an important contributor of nuclear power plant wastes (especially dismantling wastes). As it decays by electron capture; its proper detection is very difficult. X-ray spectrometry,...
The routine monitoring, as a part of radiation protection from radioactive materials released into the environment, is established in many countries worldwide. A radionuclide of particular interest is Sr-90, which is, due to its long half-life, one of the most hazardous radionuclide. As it is pure beta emitter, its isolation prior determination is necessary. In recent years, materials based on...
Innovative analytical methods for the determination of radionuclides are essential to optimize and reduce costly and time consuming sampling, and simultaneously to reduce potential radiation exposure of the operating personal. The AUTORAD platform is an automated and portable system for the separation, pre-concentration and determination of key radionuclides using flow scintillation counting....
The sequestering of uranium from the ocean is an attractive choice for clean energy due to its vast inventory (about 4.5 billion tons). In this regard, the extractant with high binding affinity to uranyl (UO22+) is desired. In the past few decades, amidoxime (AO) has been screened as the most promising candidate, and various absorption materials bearing this ligand or its derivatives have been...
Radium is the daughter nuclide of Naturally Occurring Radioactive Materials (NORM), uranium and thorium, which exists in several isotopes. Accordingly it incites great interest in various fields of application such as: environmental monitoring, analytical and medical uses(Gott et al. 2016). Due to its extensive use (in food products, in heating pads and suppositories, in cosmetics, as a...
This work is devoted to applications of the time-resolved laser-induced luminescence (TRLIF) spectroscopy and time-resolved laser-induced chemiluminescence (TRLIC) spectroscopy for detection of lanthanides and actinides. Pu, Np, and some U compounds do not produce direct luminescence in solutions, but when excited by laser radiation, they can induce chemiluminescence [1-4] of chemiluminogen...
The redox behavior of actinides is particularly complex because these elements have both many degrees of oxidation and many disproportionation reactions. In the case of plutonium, the most common oxidation states in the aqueous phase are +3 to +6. For the +3 and +4 oxidation states the solution ions are in the aquo hydrate form whereas the +5 and +6 oxidation states are in the "yle" form, ie...
The hot compressed water (HCW) is a remarkable reaction medium. In the nuclear field, the HCW method has been successfully applied in chemical synthesis and separations, nuclear waste treatment, studies of accelerated corrosion of cladding materials, etc. Moreover, the supercritical water (SCW) reactor is a concept of GenIV reactors under consideration.
We have employed the HCW (here...
Complexity of An chemistry in aqueous oxo-salt systems is dominated by their redox behavior. It’s became even more complex in the systems where oxo-salts are also redox sensitive, for example in Se and I based systems. In order to better understand the chemistry of An in Se based oxo-systems we performed a series of systematic research on reactivity and phase formation of An bearing selenates...
Magnox PuO2 packaged before 1975 has become contaminated with Cl-, from thermally degraded PVC bags it was stored in, and water, from exposure to the atmosphere. Heat treatment is the preferred method for decontaminating the PuO2 for storage before either subsequent reuse as Mixed Oxide (MOX) fuel or safe disposal in a Geological Disposal Facility (GDF). Ion chromatography experiments carried...
As known, in classical crystal chemistry special attention is paid to closest sphere packings, which satisfy the Laves’ maximum space filling (MSF) principle. The most important to crystal chemistry closest sphere packings are the face-centered cubic (fcc) and hexagonal close-packed (hcp) ones. In terms of such packings, atoms in crystal structures are treated as hard spheres of constant...
The halogen family is generally assumed to stop at iodine. Does astatine, element 85, continue the vertical trend of the halogens, does it behave like a metal? Unfortunately, little is known of the basic chemistry of astatine: it is a rare (only short-lived isotopes can be produced) and “invisible” (the amount of produced 211At requires working at ultra-trace concentrations) element. In the...
In any advanced nuclear fuel cycle, partitioning and transmutation (P&T) is a key strategy to reduce spent nuclear fuel’s radiotoxicity and heat generation: Long-lived minor actinides (MA) are partitioned from spent nuclear fuel and subsequently converted to fuel pins or targets. These are used as nuclear fuel in fast reactor systems where the actinides are fissioned to short-lived...
Uranium metal as well as other light actinides are weak Pauli paramagnets, i.e. do not exhibit magnetic moments. The reason is a large overlap of the 5f wave functions centered on nearest U neighbours. The 5f states form consequently a broad 5f band. Increasing the U-U spacing in compounds makes the 5f band narrower and eventually U moments are formed and order (ferro- or antiferromagnetic...
The CeSNEF L-54M was a homogeneous nuclear research reactor fueled by a uranyl sulfate aqueous solution enriched by 19.94% 235U. It was commissioned by Politecnico di Milano to Atomics International in the late '50s. After 20 years of operation, in 1979 the reactor was definitely shut down. Since then, Politecnico di Milano decided to manage the entire structure according to in-situ safe...
Although thorium dioxide is considered as a replacement for UO$_2$ as a matrix for nuclear fuel, there are practical problems which must be resolved before deployment. These include the poor sinterability and the cost of manufacture. ThO$_2$ is the most stable binary oxide and thus requires higher temperatures than UO$_2$ to sinter to the required densities of ≥95%. The sintering temperatures...
Éric Simoni1, Jérome Roques1, Christophe Den Auwer2, Loïc J. Charbonnière3,Pier-Lorenzo Solari4
1Institut de Physique Nucléaire d’Orsay, CNRS-IN2P3, Université Paris-Sud, Université Paris-Saclay, Orsay, France
2Institut de Chimie de Nice, Université Côte d’Azur, CNRS, Nice, France
3IPHC, UMR 7178 CNRS/ Université de Strasbourg, Strasbourg , France
4MARS beamline, Synchrotron SOLEIL, Gif...
During a normal operational regime of the nuclear power plants (NPPs) equipped with pressurized light water reactors (PWR), 3H and 14C are two biggest contributors to the effective dose of population. While 3H is responsible for the highest dose from all nuclides discharged in liquid effluents, 14C causes the highest dose from the nuclides liberated in airborne discharges. Monitoring of the...
Because of their characteristic properties, room temperature ionic liquids (RTILs) are considered to be suitable alternatives to presently used systems in the field of spent fuel reprocessing and decontamination/recycling of materials contaminated with radionuclides. Electrochemical separations from RTILs are highlighted processes in the field and Co is one of the most common contaminants...
Large-scale experiments which have been or are being established in order to answer some fundamental questions of nuclear physics, such as the SuperNEMO experiment, have been recently arising the need for radiopurity measurements on the nBq/g or even sub-nBq/g levels. One of the biggest challenges of these experiments is to reduce the background radiation to minimal values. The isotope source...
Sorption behavior is one of the most important characteristics of material considered to be used in engineered barrier on the sites for radioactive wastes repositories. One such site in Russia is located near Krasnoyarsk on the Yeniseyskiy site, in the Nizhnekansky rock massive. It is designed for intermediate and high level radioactive wastes, including self-heating radioactive wastes...
Ivanets A.I.1, Shashkova I.L.1, Kitikova N.V.1, Radkevich A.V.2, Sillanpää M.3,4
1Institute of General and Inorganic Chemistry of the National Academy of Sciences of Belarus
2Joint Institute for Power and Nuclear Research – Sosny of the National Academy of Sciences of Belarus
3Laboratory of Green Chemistry, Lappeenranta University of Technology
4Department of Civil and Environmental...
Modern geoecological situation of “Crystal” peaceful underground nuclear explosion (PUNE) area basing on the geochemical and the geophysical sounding data is considered. New data of the contents of radionuclides in surface and underground waters are obtained.
Geophysical transient electromagnetic sounding, in other words - time-domain electromagnetic sounding method (TDEM) along two profiles...
Graphene-based materials (GBMs), such as graphene oxide (GO) have previously been shown to demonstrate exceptional surface sensitivity [1], sorption capacity [2] and selectivity [3] for radionuclides. In addition, it has been found that the selectivity of GO towards certain radionuclides can be further improved by covalent attachment of chelating ligands. Such modifications have been shown to...
Hexavalent uranium is a prominent radioactive contaminant in both sediments and aquifers around nuclear activity sites, and poses a potential health and environmental risk to the biosphere. Understanding on the detailed interaction at the solid-liquid interface between uranium and granite is crucial for the safety assessment of high level radioactive waste geological repository in granitic...
Nanoparticles of metal oxides with high specific surface area show high adsorption towards selected radionuclides with fast kinetics. Metallic nanooxides were tested for separation of selected radionuclides (Am-241, Co-60, Cs-137, Sr-90) from simulated spent decontamination solutions containing citric acid. Following materials, prepared by photoinduced synthesis, were tested: NiO, NiO/TiO2 and...
After 30 years of accident on the Chernobyl NPP radioactive contamination in 30-km Chernobyl zone is determined by long-lived radionuclides of Cs-137, Sr-90 (with the half-life time 30.1 and 29.1 years, respectively) and alpha-emitting isotopes of Pu-238,239,240 and Am-241, also known as transuranium elements (TUE) (Sokolik 2004; Kashparov et al. 2003).
The overall aim of this article is to...
Artificial reservoir V-17 (Old Swamp) was formed as a result of the construction of dams in 1952 and 1954 (MAYAK Production Association), located in a natural depression relief. Intermediate level liquid radioactive wastes (ILLW) have been discharged to this reservoir since 1949. The water surface area of the lake is 0.13 km2 with the volume of 0.36 Mm3. The maximum depth is 6.5 m with the...
Decomposition of aqueous solutions of uranyl nitrate in a matrix of granulated silica gel (KSKG grade) under the action of microwave radiation (MWR) was studied. Microwave irradiation leads not only to formation of solid decomposition products UO3, UO2(OH)NO3, and their hydrates in pores of KSKG granules, but also to accumulation of gaseous NOx and H2O. The presence of NOx in KSKG pores leads...
The crucial agents in partitioning of high level liquid nuclear waste are organic ligands capable of selective complexation of the actinides and lanthanides. To evaluate their applicability, it is necessary to study the stability against undesirable reactions of these ligands, causing their structural changes. One of the main cause for degration is represented by reactions with highly...
Operation of the nuclear power plant is accompanied by the radioactive contamination of internal and external surfaces of equipment. Usually, the main part of surface contamination of the equipment's nuclear power plant is due to activated corrosion products. Decontamination of removable equipment can be done in various ways, depending on its size and design features. Electrochemical...
Currently proposed concepts for safe isolation of radioactive wastes imply development of a multibarrier system which consists of both natural and engineered barriers. Hosting rock of depository serves as a natural barrier. It appears for already-existing depositories and disposal facilities. It is naturally chosen on the stage of disposal development. Vertical and horizontal curtains of...
Staff and patient are exposed to un avoidable radiation exposure to a wide range of radionuclides, as 99mTc, 67 Ga and 131I during nuclear medicine procedures. Although the frequency of the nuclear medicine is increasing, few data are available regarding ambient and patient exposure worldwide. The The International Commission on Radiological Protection (ICRP) has lowered the annual dose limit...
Most of the migration data for radium in the performance assessment of deep geological repository, which are used in modelling the long-term safety, were obtained from experiments performed with its chemical analogues - barium and strontium. To our knowledge, there are few data available on radium migration in the engineered barrier of compacted bentonite, possibly due to difficult work with...
It is required to secure decontamination technology that is easy to apply and minimizes the generation of secondary wastes for large-scale equipment and large-area decontamination, which are difficult to be applied structurally when massive repair or decommissioning of nuclear facilities. In this respect, decontamination foam has a potentially wide application in the removal of contaminants...
Thorough understanding of the aqueous complexation of U(VI) with ubiquitous inorganic ligands, such as hydroxide and carbonate, is crucial for predicting U(VI) mobility in natural and engineered systems, since retardation processes largely depend on the metal speciation. U(VI) hydrolysis [1] and complexation with carbonate in weakly alkaline media [2] have been extensively studied. This work,...
Background and Aims:
Vascular adhesion protein-1 (VAP-1) is an endothelial glycoprotein present on the endothelial surface of tissues affected by infection/inflammation that recruit lymphocytes from blood. VAP-P1 is a VAP-1 selective peptide (sequence GGGGKGGGG) which, according to previous studies, conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and...
Vast territories with soils contaminated by radionuclides (RN) and/or mercury have appeared as a result of anthropogenic accidents, long-term activity of mining and processing plants, heat power plants, nuclear fuel cycle industry, as well as a consequence of decommissioning of such objects. These contaminants easily get involved to migration processes in the environment and frequently cause...
Future nuclear fuel cycles based on fast reactors are being developed in many countries. New nuclear fuel cycles include the reduction of long term radiotoxicity of nuclear waste by partitioning and transmutation of long lived transplutonium elements. So the selective recovery of transuranium elements, especially actinides (III) – americium and curium, from the high lever radioactive waste...
195mPt is isomeric radionuclide with the great prospect for use in nuclear medicine, due to high yield of Auger electrons, good for small malignancies treatment, mild gamma-radiation for medication distribution control without almost any damage to healthy tissues. These properties perfectly suit personalized approach for treatment of cancer which is developed into theranostics in...
Alpha induced reactions are being implemented in the imaging and industrial fields. The alpha induced reactions will be implemented in those fields by the patent pending Switchable Radioisotope Generator (SRG). The SRG allows control over the alpha induced reactions by manipulation of the alpha producing material and the target isotope. To prove the effectiveness and practicality of the SRG,...
Inner and outer safety barriers are constructed when decommissioning nuclear fuel cycle facilities takes place. Combination of different barriers prevents leakage of radionuclides and other pollutants into environment.
The outer barriers formation in geological media is carried out by injection method that allows one to minimize significance of hosting rocks contribution for depositories...
The main goal of the project Development of tools for Studying Contaminant Transport in fractured rock environment (TH02030543; 2lsConTra), funded by Czech Technology agency, is to develop tools for evaluation of migration and retention of potential contaminants in the rock environment as the key input values the safety assessment of anthropogenic activities. Those may release contaminants...
Diffusion and sorption of radionuclides in veined gneiss from Olkiluoto, Finland
H. Aromaa(1), M. Voutilainen(1), J. Ikonen(1), M. Yli-Kaila(2) and M. Siitari-Kauppi(1)
(1)Department of Chemistry, University of Helsinki, P.O. Box 55, 00014 University of Helsinki, Finland
(2) Posiva Oy, Olkiluoto, 27160 Eurajoki, Finland
A project “rock matrix REtention PROperties” (REPRO) at ONKALO, the...
Over the last decades, membrane methods (especially reverse osmosis) have been increasingly used for treatment of liquid radioactive waste (LRW). The reverse osmosis methods are most efficiently used in combination with microfilters and ion exchange filters. Based on experience of using the NITI-designed modular sorption membrane system (MSMS) in LRW treatment and concentration process, an...
Experimental work within the CEBAMA project focuses on alteration and interaction studies on cementitious materials (based on Portland type CEM II, w:c = 0.45, OPC) in contact with groundwater (GW) from Underground Research Facility Josef and with bentonite suspension (Czech B75 bentonite) in pressure vessels during three sampling campaigns (9/18/27 months) under in-situ (10°C) and high...
Bentonote clays are widely used as engineering barrier materials for radioactive waste disposal into geological formations due to their low permeability, considerable sorption capacity in relation to radionuclides, good swelling ability, heat resistance, thermal conductivity. Nowdays several bentonites deposits in Russia and
CIS countries are currently being developed that are Zyryanskoe...
Iodine radionuclides largely define radiation hazard at nuclear power plants under both normal operation and emergency. The factors that determine the high level of potential hazard of iodine are its volatility and a possibility to remain in various physical and chemical forms such as iodide (I-), molecular (I2), iodine organic, for example, methyl iodide (CH3I), iodate (IO3-) or periodate...
The application of 68Ga –labeled peptide for tumor diagnosis is growing very fast in the recent years. One of the traced peptide for tumor diagnosis in nuclear medicine is [68Ga]GaDOTA-TOC. The aim of the work was GMP preparation of [68Ga]GaDOTA-TOC for application in nuclear medicine for a routine diagnosis using automated production with TRACERlab® MX module and quality control according to...
Over the past several decades nuclear medicine turned into an integral part of clinical practice in developed countries. The therapeutic radiopharmaceuticals (RPh), developed and currently used in Russia, are applied for treatment of oncological diseases, but due to their versatility, RPh can be useful in other fields of medicine.
For this purpose formulation development of a medication on...
Hydroxyapatite based materials including nanoparticles (HAp-NPs) are widely used in medicine because of their stability in various biological media [1]. The HAp-NPs also belong to promising drug carrier systems for medicinal radionuclides such as F-18 as the part of multipurpose theranostic system with other therapeutic and diagnostic radionuclides [2]. HAp-NPs can show uptake by cancer tissue...
Mineral-like magnesium-potassium-phosphate (MPP) compound samples were synthesized during the immobilization of a high level waste (HLW) simulator. The phase composition and structure of compounds were studied and their physico-chemical properties, including mechanical and thermal stability, were determined. The high hydrolytic stability of the MPP compound was established: the differential...
Selenium-79 (79Se) is one of the important long-lived fission products exists in radioactive waste and has toxic anionic species in an aqueous environment. Consequently, 79Se is considered as a key radionuclide that should be taken into consideration in safety assessments in radioactive waste repository. Commenly, the usage of bentonite as a buffer material is suggested in radioactive waste...
Superparamagnetic iron oxide nanoparticles (SPIONs) are being studied as contrast agents and drug delivery vehicles in medicine, mainly for easy preparation, low toxicity, biocompatibility and their magnetic properties. SPIONs have become a promising tool in the magnetic resonance imaging, magnetic drug targeting, hyperthermia anti-cancer strategy, and enzyme immobilization. The scope of our...
Keyword – proton induced nuclear reaction, experimental cross sections
The Coordinated Research Project (The International Atomic Energy Agency), entitled “Therapeutic Radiopharmaceuticals Labelled with New Emerging Radionuclides (67Cu, 186Re, 47Sc)” is focused on production methods of the 67Cu, 186Re and 47Sc radioisotopes as...
Metal Organic frameworks (MOFs) are self-assemblies of metal ions and organic ligands, known for their high crystallinity and porosity. The wide range of high and accessible porosity allows them to be explored as alternatives for traditional porous materials and for many new applications. Some of them exhibit an extraordinarily huge surface area together with a high chemical stability.
One of...
Nowadays computer models of fuel fabrication/refabrication, SNF reprocessing and waste management processes are under development as part of technologies front-end and back-end of closed fuel cycle. One of them is software package “VIZART” [1,2]. Code “VIZART” is used for material flow calculations of technological schemes and dynamic calculations of equipment work, taking into account...
Dissolution of corrosion layers is strongly connected with the problem of decontamination and decommissioning of nuclear facilities, which has become of the current issues in many countries. The key process to decontaminate metals, is to dissolve surface corrosion layer and remove radionuclides. From corrosion studies on the surface of stainless steel under primary circuit conditions of...
Foam decontamination process has a potentially wide application in the removal of contaminants from large components with complex shapes or large area or large volumes. This process can be applied to any direction regardless of walls, floors and ceilings, and basically it has the advantage of generating less secondary wastes. However, there is a disadvantage that the decontamination factor...
The present development is aimed at creation of thermo-collapsing radiopharmaceuticals for brachytherapy based on thermo-sensitive copolymers with chelated beta-emitting radionuclide 153Sm. The preparation is a polymer solution and is made of two components, each loads individual function.
The task set in this development is solved with component-wise division of the radiopharmaceutical’s key...
European demand for chromium has grown dramatically, leading to the need for a detailed understanding of recycling of steel sludges and separation methods. To simulate these processes, we will use the radiotracer technique. 51Cr (T1/2 = 27.7 d) was choosen as a radionuclide. The isotope can be produced by the nuclear reaction natV(p,n)51Cr at a cyclotron. We used our recently installed...
68Ga (T1/2 = 68 min) is used for molecular imaging in positron emission tomography. 68Ga decays via 1.92 MeV positron emission (89%) and electron capture (11%). Due to suitable half-life for radiolabeling and easy availability from radionuclide generator, interest in 68Ga labelled compound has increased.
The most convenient method of 68Ga production is usage of 68Ge → 68Ga radionuclide...
Recent years some alternative techniques are being developed for solid state matrixes producing for immobilisation of liquid and mixed state radioactive wastes. Magnesium-potasium-phosphorus ceramics (MPP ceramics) matrix are considered to be a promising solid state matrix for immobilisation of liquid and mixed state radio-active wastes as alternative to cement and glass matrix. The major...
In the current time the task of management the accumulated volumes of irradiated graphite obtained by uranium-graphite reactors decommission (over 250,000 tons in the world) is acute in Russia along with other countries. It is known during the reactors operation the carbon and chlorine present in the nuclear graphite become activated. Besides various incidents during reactor exploitation occur...
Different methods are available for the purification of recovered enriched water from FDG synthesis units. Procedures for organic solvents elimination as: irradiation of the water with UV light, oxidation with KMnO4/NaOH (Rötering et al., 2015), electrolysis (Huang et al., 2003; Weber et al., 2003), ozonolysis (Asti et al., 2007) or He gas purging are proposed. All these methods can remove...
The extraction system that supposed to be used for extraction of radionuclides must have suitable extraction and hydrodynamic characteristics, as well as to be explosive- and fire-safe in operation. The main reason of the worsening the circulating extractant quality is the formation and accumulation of various organic compounds under irradiation. The main products of radiolytic degradation in...
Reprocessing of spent nuclear fuel became the key issues for the environmentally friendly and sustainable development of nuclear energy. For the future development of nuclear energy requirements, the concept of an accelerator-driven advanced nuclear energy system (ADANES) has been proposed in China. ADANES consists of a burner system and a fuel recycle system. The waste transmutation,...
In The Czech Republic a selection of locality for deep repository of spent nuclear fuel is currently in progress. For the safety evaluation it is necessary to verify that the radionuclides penetrating the engineered barriers and a geosphere are not reaching a biosphere in high concentrations. Flow123D and GoldSim SW are used for the solute transport simulations in a geosphere. The advantage of...
The post-accident measure demand has raised after Fukushima Daichi accident. One of the main challenges was related to treatment of large volumes of the highly radioactive waste waters, being generated during the severe accident mitigation. Therefore UJV Řež in the cooperation with CEZ, a.s. and Slovenské elektrárne, a.s. has started to review the concept and potential design of radioactive...
To evaluate the retention potential of the concrete barrier in a nuclear waste repository towards actinides in the presence of high saline water, leaching experiments with actinide-doped calcium silicate hydrate (CSH) phases were performed in highly saline electrolytes. Therefore, U(VI)- and Cm(III)-doped CSH phases with different C/S ratios (1.0-2.0) were synthesized directly in presence of...
In order to develop resins with selectivity to U(VI) in HNO3 media, we have synthesized several polymer beads with the structure of a monoamide as the functional group. For wider applications of these resins including treatment of highly-radioactive solutions, it is necessary to investigate their stability under irradiation conditions. In this study, resins with a chain-type monoamide and a...
Radioactive wastes, especially high-level waste (HLW) and intermediate-level waste (ILW), generated predominantly in nuclear fuel cycles contain a wide variety of radionuclides including long-term radionuclides and the wastes contain also various chemicals, often complexation agents used for decontamination purposes. Due to the presence of large quantities of long-term radionuclides, HLW and...
Pertechnetate (TcO4-–) is among the anions that are considered the most environmentally mobile. This is due to its relatively large size and low negative charge density distributed at the four oxygen atoms [1-4]. The negatively charged anions repel from the negatively charged surface of most minerals. Conversely, they are attracted by positively charged residues of nitrogenous bases like...
In the technological system of high-burnt irradiated nuclear fuel reprocessing that is being developed, before entering the affination phase, all the reductant from the previous phase of reducing reextraction must be deconstructed and the Pu(III) must be oxidized to Pu(IV). For this process a reagentless oxidation method using an activated carbon catalyst (VNIITU-1) was proposed. As a result...
The effect of dissolved hydrogen on the oxidative dissolution of highly Pu-doped MOX and externally irradiated UO2
Nuclear Chemistry/Industrial Materials Recycling, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
Swedish Nuclear Fuel and Waste Management Co., SE-101 24 Stockholm, Sweden
The release of radiotoxic species from future final geological nuclear waste...
Investigation of causes of the accidents, leading to explosions and fires at nuclear facilities, is an important component in ensuring nuclear and radiation safety because of the significant impact of such accidents on the personnel, population and environment. Among a large num-ber of nuclear facilities, the most dangerous are SNF reprocessing plants, which are currently using processes such...
During reprocessing of spent nuclear fuel by PUREX process uses an extractant that consist of a mixtures of TBP in a light hydrocarbon diluent. In the Russian industrial practice mainly used saturated aliphatic hydrocarbons, but currently discusses the possibility of using branched-chain hydrocarbons, which have advantages properties over the first. Because in the technology process extractant...
We present on the development of the Micro-Optical Ring Electrode (MORE) for the analysis of trans-uranium elements in aqueous mixtures. The MORE is a photo-electrochemical device based on a ring microelectrode that uses the insulator interior to the ring as a light guide. This single device exploits the unique photophysical and electrochemical properties of multiple analytes present in...
Long-term controlled storage or disposal is one of the major stages of liquid radioactive waste (LRW) management. The preparation of LRW for this stage includes the conversion of waste into a stable solidified form. In recent years, researches devoted to the development of new methods of LRW solidification are carried out using a magnesium-potassium-phosphate (MPP) compound based on the...
The work describes an experimental study of the determination of chemical stability of protective coatings under conditions of severe accidents at nuclear power plants. Another task of the work was to evaluate the thermal degradation of the coatings and the analysis of the resulting solids (debris), which can cause overload of cooling systems, as well as be a source of release of combustible...
Cementing methods is mainly used for low and intermediate level radioactive waste. Currently, cement stone is almost never considered as a matrix for immobilizing high level waste due to probable low durability of as well as to radiolysis cement hydrates and pore-water under high radiation dose.
The objective of this report is the assessment of cement compounds affected by high radiation dose...
Samples of the zeolite clinoptilolite, mined from Mud Hills in California, have been tested in column experiments to determine their ability to remove radioactive Cs+ and Sr2+ ions. The clinoptilolite was effective in removing both Cs+ and Sr2+ from aqueous solution. Increasing concentrations of Ca2+, Mg2+, Na+ and K+ competed with the Cs+ and Sr2+, and increased elution of Cs+ and Sr2+. Ca2+,...
One of the ways for diminishing risks during storage and burial of Purex-process HLW, which are arising from high heat evolution by -emitting 90Sr & 137Cs, is recovery of long-lived TPE radio-nuclides, especially 241+243Am, which could be recycled in NFC by inclusion in the fuel for fast reac-tors. Commercial TPE partitioning in Russia has been carried out and developed using fluorinated...
Liquid radioactive waste (LRW) represent serious environmental problem due to their multicomponent composition: presence of long-lived radionuclides with variable oxidation states as well as nitrate ion in high concentrations. One of the most problematic types of LRW are alkaline waste generated in the PUREX process of spent nuclear fuel recovery. Annually are generated about 6490 m3 of...
One of the prospective directions in the development of the generation IV reactors is the use of liquid metals as a coolant. At the same time, to ensure compliance with all the requirements, it is necessary to solve many practical problems and challenges. The subject of this work are radiochemical investigations required for licensing of the MYRRHA reactor conducted within the MYRTE-project...
Recently, first gas-phase chemical experiments aimed to investigate the adsorption behavior of the heavy elements Cn and Fl on selenium surfaces were conducted. During this experimental campaign, an unexpected formation and transport of a volatile At species was observed. Monte-Carlo simulations of the deposition pattern of this species on quartz, selenium, and gold surfaces were performed,...
7Be (half-life, 53.2 d) and 22Na (half-life, 2.6 a) are naturally occurring radionuclides of cosmogenic origin. Intrusions of stratospheric air masses into the troposphere followed by dry or wet deposition are the main processes transferring 7Be and 22Na to the earth’s surface. These two atmospheric cosmogenic nuclides are simultaneously generated in the upper atmosphere and have similar...
The Osamu Utsumi Mine located at the Poços de Caldas plateau, Minas Gerais state, Brazil, was the first uranium mine exploited in the country, in the Poços de Caldas Mining-Industrial Complex (CIPC) of the Nuclear Industries of Brazil (INB). The operational phase for extracting and processing uranium lasted from 1982 to 1995, when activities were interrupted initiating the decommissioning...
There have been two nuclear power plants (NPPs) in operation in Slovakia - Jaslovské Bohunice and Mochovce. Radiocarbon as one of the most important radionuclides for delivering of long-term radiation doses to the public has been regularly monitored in the NPP surrounding areas as well as in the city of Bratislava. In the vicinity of both NPPs atmospheric carbon dioxide has been sampled on a...
The techniques of highly sensitive mass spectrometry is achieving rapid development recently. Several elements or nuclides that were not supposed to be applicable in that technique are now quantitatively analyzed. Especially, for long-lived actinides elements, the techniques are becoming more and more important as a promising alternative of radioactivity measurements. The tracer nuclide for...
For now, most radioactive reference sources are manufactured with electro-deposition. However, the electro-deposition procedure takes quite a long period of time and the operations are conducted using flammable solvents under high temperature. In addition, the products of electro-deposition may be oxidized and exfoliate after years of usage which can cause extra uncertainty of quantitative...
Detailed understanding of reactive transport in geomaterials of chemical species, including radionuclides, is required for the utilization of the subsoil, e.g. for designing ore production by in-situ leaching, or for radioactive waste disposal. To complement the well-established conventional approach, i.e. computer model simulations based upon bulk material parameters and geochemical data...
Theranostic Tumor-Specific Gold-198 Nanoparticles Through Green Nanotechnology—Implications In Nanomedicine For Concurrent Molecular Imaging and Tumor Therapy
Kattesh V. Katti, Kavita K Katti, Menka Khoobchandani
Institute of Green Nanotechnology, University of Missouri Cancer Nanotechnology Platform;University of Missouri; Columbia, Missouri 65212, USA
http://katteshkatti.com/
&
Ademar B....
A problem of separation of trivalent f-elements is one of key problems of spent fuel reprocessing as well as processing of lanthanide-containing mineral resources. Chemical similarity leads to development of long cascade separation equipment with low efficiency on each step. Development of new selective ligands may allow us to simplify separation scheme and increase process efficiency.
"Deep...
Particle Induced X-rays Emission (PIXE) analysis is non-destructive method used in many fields of interest. With this method, an absolute concentration of investigated elements can be determined at ppm levels. Collaboration between the Medical Faculty and the CENTA laboratory was set up to use PIXE analysis for determination of iron concentrations in rabbit and human brain tissues, which...
Contemporary alpha ray spectrometry suffers from number of shortcomings: e.g. high time consumption, requirement of expensive chemicals and electrodeposition equipment as well as changing electrodeposition yields. Nevertheless, these and other unfavorable aspects have to be accepted to obtain decay informations about the alpha particle emitting radionuclides.
The aim of our current project is...
Nowadays the concept of closed nuclear fuel cycle (CNFC) for fast neutron reactors (FR) is developed in Russia. CNFC can be implemented for FR with sodium coolant using mixed uranium-plutonium oxide (MOX) fuel and for reactors with lead coolant using mixed U-Pu-(Np-Am) nitride (MINT) fuel.
By “PRORYV” Project the combined “РН-technology” was proposed as the technology for reprocessing of MOX...
Radio-imagers, mainly dedicated to biological and medicine applications, can be used to reconstruct 2D mapping of radioactivity on a surface. The resulting image, called Digital Autoradiography (DA), gives a non destructive analysis of radioactivity.
Recently, a new scope for the radio-imagers has emerged: nuclear facilities decommissioning. Indeed, in such context, surface contamination...
Study on chemical separation method for the analysis of isotope ratio of 135Cs to 137Cs in soil
Asako Shimada, Taro Shimada, Seiji Takeda, Tetsuji Yamaguchi
Nuclear Safety Research Center, Japan Atomic Energy Agency
In order to confirm the completion of the decommissioning of a facility, the radioactivity concentration of soil at the site has to comply with criteria for site release....
Efficient remediation of liquid radioactive waste, produced as in research and medicine, is crucial for increasing safety during the necessary storage of this material. A novel bio-magnetic nano-composite sorbent based on a natural product (Karaya gum) and magnetite nanoparticles was tested for the efficient removal of radioactive phosphorus 32P from liquid radioactive waste. This non-toxic...
The present work describes a method for the preparation and validation of plutonium age dating reference materials [1]. The prepared reference samples can be used to validate experimental protocols for determining the production date of plutonium via the 234U/238Pu, 235U/239Pu, 236U/240Pu and 241Am/241Pu chronometers. The starting material was prepared using reactor-grade plutonium, which was...
The disposal of mercury from nuclear applications that contains radionuclides due to contamination or neutron activation is very challenging, not only due to its radiotoxicity but also due to its high chemotoxicity and mobility in the environment. Elemental mercury has been used in several nuclear facilities, for example as coolant and shielding material in early fast reactors, as sealant in...
Cellulose is a very common organic polymer and also present in considerable amounts in low and intermediate level wastes (LILW). Since it is considered to stabilize LILW with cementitious materials and to use cement-based materials as construction and backfilling material, the alkaline degradation of cellulosic material has to be taken into account. This process will lead to the formation of...
Radium is the heaviest alkaline-earth metal. It has no stable isotopes and the most long-lived and abundant isotope is $^{226}$Ra with a half-life of 1600 years. Radium and its short-lived daughters are among the most radiotoxic elements. Enhanced radium concentrations can be found in different waste streams: uranium and other metal mining, fossil fuel combustion, oil and gas production among...
The nutrient cycle of soils is mainly determined by the concentration of macro and micro nutrients in the soil solution directed by the interactions between the solid phase of soil and the soil solution. These interactions are essential in case of nutrients, such as phosphate anion, strongly binding some soil components. Phosphate anion can precipitate with different cations (e.g. iron,...
The High Flux Reactor in Petten, Netherlands, is used for the production of medical isotopes as well as a material research reactor; during its exploitation several types of radioactive wastes are produced and accumulated.
That is the case in particular for the Ion Exchange Resins (IER) in use to treat the water of the primary water circuit of the reactor and the demineralizing basin....
The transfer of radionuclides into the food chain is of central concern for the safety assessment of both nuclear waste repositories and radioactive contaminated areas, such as legacies of the former uranium mining. The interaction of radionuclides with plants is mostly described by transfer factors without knowing the underlying processes. However, previous studies showed, for instance, a...
Carbon-14 (half-life 5,730 years) is a key radionuclide in the assessment of the safety of a geological disposal facility (GDF) for radioactive waste. In particular, the radiological impact of gaseous carbon-14 bearing species has been recognised as a potential issue. Carbon 14 is expected to be released from a GDF over a timescale of several thousand years. A number of radioactive gases will...
Strontium-90 is released to the environment during accidents in nuclear facilities and nuclear explosions. It can penetrate human organisms with food, including milk. Once absorbed into the body, it is accumulated mainly in bones. Studies were conducted in order to evaluate the current levels of 90Sr in cow milk after more than 30 years from the Chernobyl catastrophe and calculate...
Irradiated graphite (i-graphite) is a typical nuclear waste arising from the decommissioning of some nuclear power plants and research reactors. According to the current nuclear waste management strategy in Germany, i-graphite discharged from commercial and research reactors is to be disposed of in a deep geological repository for low and intermediate level radioactive wastes, which requires...
The Fukushima-Daiichi Nuclear Power Plant (FNPP) accident released a substantial amount of radioactive nuclides into the atmosphere and caused extensive contamination of the environment. Cs-137 and Sr-90 are typical fission nuclides that have a great influence on the environment for several ten years after the accident because of its half-life (30.1 y and 28.9 y). After the deposition onto the...
A fast radioanalytical method has been developed to measure 210Po in tobacco samples. After microwave digestion Polonium is extracted quantitatively from a 1 M hydrochloric acid solution into a solution of tri-octylamine in toluene. The extract was measured by Liquid Scintillation Counting in alpha mode. Caused by the high counting efficiency the counting time per sample can be reduced...
This study was aimed to development and application of polymer composite formulations for “dry” decontamination of the spent nuclear fuel storage of mobile NPP “PAMIR” with gas-cooled nuclear reactor using heat carrier N$_{2}$O$_{4}$.
Polymer composite formulations for “dry” decontamination and their operation characteristics (decontamination efficiency, consumption rate), and at evaluating...
Technetium isotope 99Tc is a fission product of environmental concern, due to its high mobility and its elevated lifetime (2.13×105 years). Among their possible oxidation states, Tc(VII) and Tc(IV) are the most stable ones. On one hand, Tc(VII) occurs under oxidizing redox conditions, being pertechnetate (TcO4-) the main species, which is considered...
Phosphogypsum from past production of phosphoric acid was dumped into self-contained ponds on the south bank of Tejo River, at the industrial area of Barreiro near Lisbon, for decades. Production and disposal of phosphogypsum was discontinued in the early 90’s due to changes in industry, and a contamination assessment was performed at that time. Since then large amounts of phosphogypsum have...
