Wyniki wyszukiwania - BazTech

1

Metody pomiaru promieniowania i identyfikacji nuklidów w zdarzeniach CBRN: analiza badawcza z projektu EU-RADION

Szklarski Łukasz, Jakubowska Alicja, Maik Patryk, Wołoszczuk Katarzyna, Wieczorek Anna, Krajewski Paweł

Postępy Techniki Jądrowej

|

2023

|

z. 4

2--17

PL

Praca wyznacza implikacje zdarzeń radiologicznych w scenariuszach przemysłowych i terrorystycznych, wykorzystując wnioski z projektu EU-RADION i gruntownego przeglądu literatury. Wyniki podkreślają konieczność skutecznej ochrony przed promieniowaniem i środków reagowania w nagłych przypadkach, podkreślając kluczową rolę postępu technologicznego we wzmacnianiu zdolności wykrywania i zarządzania zagrożeniami radiologicznymi. Badanie podkreśla znaczenie trwających badań naukowych i międzynarodowej współpracy w umacnianiu globalnej odporności na zagrożenia radiologiczne.

EN

This study delineates the implications of radiological events in industrial and terroristic scenarios, utilizing insights from the EU-RADION project and a thorough review of existing literature. The findings highlight the necessity for robust radiation protection and emergency response measures, underlining the pivotal role of technological advancements in enhancing radiological threat detection and management capabilities. The study underscores the significance of ongoing research and international collaboration in bolstering global resilience against radiological hazards.

2

Biomonitoring of radioactive contamination using benthic invertebrate communities in Manzala Lake, Egypt

Imam Noha, Bendary Reda E.

Oceanological and Hydrobiological Studies

|

2023

|

Vol. 52, No. 2

147--165

EN

Manzala Lake, the largest in Egypt’s Nile Delta, hassignificant human activity. The Lake’s ecological conditionhas recently been impacted by a significant increase inagricultural, industrial, and urban wastewater discharge. Avaluable tool for monitoring the water quality of ManzalaLake is the sensitivity of invertebrate species to varioustypes of pollution, such as radioactive contamination.Activity concentrations of radionuclides Radium-226 (226Ra),Thorium-232 (232Th), Potassium-40 ( 40K), and Caesium-137(137Cs) were measured in water, sediments and benthicinvertebrate samples in 2020. The benthic community’sspatial distribution and the radionuclides’ bioaccumulationwere evaluated to determine possible relationships.Thirty taxa of benthic invertebrates were recognised.The data illustrated that the mean activity concentrationof radionuclides in water was in the order of 40K > 232Th >226Ra > 137Cs, which changed into 40K > 226Ra > 232Th > 137Csin the sediment and benthic invertebrates. Gastropodaand Ostracoda are the dominating groups of benthos inthe lake and are related to the highest concentrations ofradionuclides. The benthos species with shells dominatedat the sites with the highest activity concentration of 226Ra,while soft-bodied organisms dominated in sites with thehighest average 137Cs activity in these samples.

3

Spektrometryczne profilowanie gamma w odsłonięciach geologicznych : metody i przykłady zastosowania

Moskalewicz Damian

Przegląd Geologiczny

|

2022

|

Vol. 70, nr 11

806-- 815

EN

Handheld gamma-ray spectrometry (hGRS) is a valuable method for geological studies. It may be applied in correlations between well-logging and outcrop strata, enhance interpretations of sedimentological data, prospect radiogenic ores and geothermal resources, and identify radiogenic hazards for society. This paper aims to review and popularize one of the research methods based on a mobile device (hGRS) equipped with a BGO (bismuth germanium oxide) scintillator. The general concept of the research method is presented in this paper. The method's perspectives and limits based on reviewed literature. Advantages of hGRS include, e.g., low cost, short data acquisition time, the possibility of studying natural exposures, and a broad set of research applications. The main disadvantages comprise relatively modest resolution of acquired data and their difficult interpretation in complex geological formations. The review is backed by sample measurements performed in various geological exposures at Bornholm Island (Baltic Sea). Measurements comprised igneous rocks exposed in several quarries and sedimentary profiles near Liesti Valley and Muleby.

4

Specific Activity of Radionuclides in Soils Disturbed by Forest Fires

Popovych Vasyl, Henyk Yaroslav, Gapalo Andriy, Bosak Pavlo, Popovych Nataliya

Journal of Ecological Engineering

|

2022

|

Vol. 23, nr 6

265--270

EN

Fires in natural ecosystems have a detrimental effect on all biota components. In the global scale, many scientific studies of prominent scientists are devoted to this topic. It should be noted that scientists have always been interested in the influence of thermal destruction of soil genetic horizons on the specific activity of radionuclides. Most of these studies began after the Chernobyl (1986) and Fukushima (2011) radiation disasters. The conducted research is focused on the specific activity of radionuclides due to the thermal effects of fires in natural ecosystems. It has been established that the edaphotopes affected by fires are naturally restored causing the restoration of soil formation processes. The specific activity of radionuclides decreases with the duration of the ground fire. Comparing the obtained data with the regulatory documentation, it was found that they do not exceed the minimum significant activity of radionuclides in the workplace. However, the increased activity of radionuclides in soils has a detrimental effect on the ecological condition and flora and fauna development. During the fire season in natural ecosystems and forests, careless handling of fire should be avoided and preventive measures should be taken to inform the public about the harmful effects of wildfire.

5

Integration of Processes of Radionuclide-Contaminated Territories Decontamination in the Framework of their Ecological-Socio-Economic Rehabilitation

Chernysh Yelizaveta, Balintova Magdalena, Shtepa Vladimir, Skvortsova Polina, Skydanenko Maksym, Fukui Manabu

Ecological Engineering & Environmental Technology

|

2022

|

Vol. 23, iss. 1

110--124

EN

Large-scale disasters at nuclear power plants (NPPs) and their consequences are still the subject of discussion by the world scientific community, which makes mankind recognize the unsolved problem of radiation pollution. Accordingly, the search for new effective biocomposite materials with high sorption capacity to eliminate harmful effects associated with radiation contamination of large territories is an urgent task on a global scale. This paper is devoted to the study of the decontamination processes of the areas contaminated with radionuclides, the search for new mechanisms of fixation of radionuclides and heavy metals in the soil using the matrix material of different origin. In order to intensify the process of radionuclide fixation in the soil-plant system the method consisting of introducing into the soil the organic-mineral biocomposite based on sewage sludge and phosphogypsum after anaerobic fermentation was proposed. It is necessary to further study the processes of sorption and radionuclides solubilization due to complexation with organic agents present in matrix materials of different nature. The mechanisms of radionuclide and heavy metal fixation using matrix material of different origin were analyzed and a general model was formed. The direction of integration of radionuclide-contaminated soil decontamination technologies into the process of ecological, social, and economic development of the territories under rehabilitation after the accidents at the Chernobyl NPP and Fukushima-1 NPP is proposed.

6

Sorption of selected radionuclides from liquid radioactive waste by sorbents of biological origin : the alkaline earth alginates

Fuks Leon, Oszczak-Nowińska Agata

Nukleonika

|

2021

|

Vol. 66, No. 4

153--158

EN

The sorption of 241Am3+, 85Sr2+ and 137Cs+ by calcium, strontium and barium alginates has been studied under different operation conditions. The most prominent adsorption was found in the pH range of 5–6 for all systems, even if the observed dependence on the acidity of the solution was small. The most favourable time for the adsorption process was found to be about 2 h for calcium alginate and 4 h for the other two sorbents.

7

Radioactive nuclei for β+γ PET and theranostics: selected candidates

Matulewicz Tomasz

Bio-Algorithms and Med-Systems

|

2021

|

Vol. 17, no. 4

235--239

EN

Positron emission tomography (PET) is an established medical diagnostic imaging method. Continuous improvements are aimed at refining image reconstruction, reducing the amount of radioactive tracer and combining with targeted therapy. Time-of-flight (TOF)-PET provides the localization of the tracer through improved time resolution, nuclear physics may contribute to this goal via selection of radioactive nuclei emitting additional γ-rays. This additional radiation, when properly detected, localizes the decay of the tracer at the line of response (LoR) determined by two detected 511 keV quanta. Selected candidates are presented. Some are particularly interesting, as they are strong candidates for theranostic applications.

8

Radiological and health hazards resulting from radioactivity and elemental composition of some soil samples

Al-Khawlany Abdu Hamoud, Khan A. R., Pathan J. M.

Polish Journal of Medical Physics and Engineering

|

2020

|

Vol. 26, Iss. 2

97--110

EN

Inspection of the radioactivity level in the soil is very important for human health and environmental protection. This study aims at evaluating the radiological hazards and pollution risks related to natural radionuclides and elements in the selected soil samples. Ten samples of soil were collected from different sites of Aurangabad-India and the level of radioactivity was measured using gamma-ray spectrometry with NaI (Tl) detector. Furthermore, the Physico-chemical properties such as pH, organic matter, electrical conductivity, moisture, soil texture, etc., and elemental composition of soils have been decided on using various standard techniques. The mean concentrations of 226Ra, 232Th, and 40K were 8.178, 17.408, and 96.496 Bq/kg, respectively, which are lower than the global average values of 35, 30, and 400 Bq/kg, respectively (UNSCEAR, 2000). The radiological hazard indices such as radium equivalent, absorbed dose, annual effective dose, internal index, external index, gamma index, excess lifetime cancer risk, etc., were calculated to assess the radiation hazards and compared with internationally recommended values which found to be lower than the permissibility limits.

9

Ecological analysis of heavy metal and radioactivity potential of Holocene sediments in Iznik Lake

Yumun Zeki U., Kam Erol

Nukleonika

|

2019

|

Vol. 64, No. 3

103--109

EN

In this study, the heavy metal and radioactive properties of Iznik Lake were investigated. Concentration values of the first (Ag, Bi, Mo, Sn, Se, Zn, As, B, Cd, Co, Cr, Cu, Ni, Pb, Pt and Sb) and second (Na, Mg, K, Ca, P, S, Fe, Al and Mn) group of elements in borehole 1 (BH-1) drilling did not show much variation from the top to the bottom of the drilling. Concentration values of the fi rst group of elements in borehole 2 (BH-2) drill samples decreased at higher levels of drilling. In addition, natural and anthropogenic radionuclides were measured by gamma spectrometry, and the results of environmental natural radioactivity of Iznik Lake and its surroundings were determined. In the measurement results, Ra-226 was found to be below the world average value at all locations. It is assumed that the determination of K-40 values above the average values was due to agricultural activities carried out intensively in the study area. Th-232 values were found to be below the world average value in drilling samples; Cs-137 values were below the background level in all samples. According to these results, the study area does not contain any unnatural radioactivity.

10

Influence of Chemical Amelioration of Solonetzic Soils on the Presence of Heavy Metals and Radionuclides in Soil Profile

Anatolievna Guzeeva Svetlana

Journal of Ecological Engineering

|

2019

|

Vol. 20, nr 5

179--183

EN

The article considers the results pertaining to the influence of solonetzic soils chemical amelioration on the presence and redistribution of heavy metals and radionuclides in meter profile of soils. Meliorative procedures were carried out 45 years ago. Phosphogypsum has been used as chemical ameliorant up to 90-s on the solonetzic soils of Tyumen region. It is a by-product of phosphates production. The objective aimed at revealing possible negative consequences connected with the introduction of the chemical elements associated with phosphogypsum. The studies showed that phosphogypsum introduction contributes to some increase in the content of active forms of heavy metals (zinc Zn, copper Cu, cadmium Cd and lead Pb) in soil. However, critical values are achieved only by active lead Pb. The evaluation of radioactive state of meadow crusted solonetzic soils after carrying out of meliorative procedures (for the same period) on the content of isotopes of thorium-232 (Th-232), calium-40 (K-40), radium-226 (Ra-226), caesium-137 (Cs-137) and strontium-90 (Sr-90) indicated that redistribution of radionuclides after chemical melioration does not cause a negative change of radiation background. Vibrations in the soil profile are connected with various initial concentration in rock formations or weathering detritus. Specific effective activity (Аeff ≤ 370 Bq/kg) testifies to the soils being studied and absence of their additional introduction with introduced doses of phosphogypsum.

11

Kolekcjonowanie, eksponowanie i obrót minerałami promieniotwórczymi

Długosz-Lisiecka Magdalena

Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie

|

2019

|

nr 7

4--8

PL

Poziom promieniowania jonizującego niektórych minerałów, odnajdywanych również w Polsce, bywa bardzo wysoki. Pozyskiwanie, kolekcjonowanie i ekspozycja takich minerałów, mimo że są naturalnymi składnikami skorupy ziemskiej, jest obwarowane przepisami. Właściwe ich przechowywanie i oszacowanie narażenia są kluczowe dla zapewnienia właściwego poziomu ochrony radiologicznej

EN

The article is a review of the principles of the safety collecting, presenting and trading of the radioactive minerals, with particular emphasis on current legislations. Activity concentrations of the three isotopes 238U, 232Th and 40K determine whether a given mineral meets the definition of a radioactive source and can be apply to assess radiological exposure for the human. For proper radiation protection, it is important to maintain the basic principles, including the rules of distance, limitation of the time and using of the shield. Particular attention has been paid to the need of radiation protection of the private owners of unique radioactive collections. Trade and transport of minerals defined as radiation sources requires notification or authorization on similar principles as their storage. The paper describe more specific duties for museum collections of radioactive exhibitions due to the publicly available and guidelines for the classification of a package containing radioactive minerals, in the public transport.

12

Centralne laboratorium ochrony radiologicznej: retrospekcja i współczesność

Bielski M.

Postępy Techniki Jądrowej

|

2018

|

z. 1

2--6

PL

Nawiązując do przypadającego w 2017 r. jubileuszu 60-lecia działalności Centralnego Laboratorium Ochrony Radiologicznej (CLOR) w Warszawie w wywiadzie z dr. Pawłem Krajewskim, dyrektorem CLOR, prezentowane są zagadnienia związane z pracą badawczą i operacyjną tej placówki na przestrzeni lat 1957-2017. Omówiono m.in. opracowane i stosowane w CLOR metody pomiarowe, techniki i technologie oraz skonstruowane w CLOR nowe rodzaje aparatury dozymetrycznej i radiometrycznej, na które uzyskano patenty. Przedstawiono także aktywne uczestnictwo pracowników CLOR w naukowych programach i projektach badawczych krajowych i międzynarodowych. Szczególną uwagę zwrócono na zainicjowaną przez CLOR akcję profilaktyczną, będącą ewenementem na skalę światową, a skierowaną na ochronę ludności, w związku z awarią EJ w Czarnobylu (podanie 18,5 mln Polaków jednorazowej dawki jodu stabilnego, o wielkości zależnej od wieku biorcy). W drugiej części tekstu skoncentrowano się na realizacji zadań, jakie należy podjąć w celu dalszego unowocześnienia systemu Bezpieczeństwa Jądrowego i Ochrony Radiologicznej w Polsce (BJiOR), w tym wzmocnienia systemu zaplecza merytorycznego Technical Suport Organization (TSO).

EN

Referring to the 60th anniversary of the establishment of the Central Laboratory for Radiological Protection in Warsaw, the interview with its Director, Paweł Krajewski presents several issues on research and operational activities of CLOR e during the period of 1957-2017. Among other issues, new measurements methods, developed and implemented in CLOR, new kinds of radiometric and dosimetric devices for which the patents have been granted, were touched upon in the interview. Also, the focus was on the active participation CLOR’s staff in science, research and development projects both at national and international levels. In addition to that, particular attention was paid to the most spectacular action undertaken by CLOR in 1986 just after Chernobyl accident, when prophylactic doses of stable iodine were administered to about 18.5 million of Poles in various amounts depending on a recipient’s age. In the second part of the interview the important questions of modernization and strengthening the Polish system of Nuclear Safety and Radiation Protection and problems of Technical Support Organizations were discussed.

13

The use of moss Pleurozium schreberi (Brid.) Mitt. as bioindicator of radionuclide contamination in industrial areas of Upper Silesia

Kosior G., Dołhańczuk-Śródka A., Ziembik Z.

Ecological Chemistry and Engineering. S

|

2017

|

Vol. 24, nr 1

19--29

EN

Mosses are good bioaccumulators of radionuclides and from the 60 of the last century, they are used as bioindicators of radioactive contamination in the environment. Concentration of impurities in moss represent the accumulation in mosses during the past 2-3 years. As a result, the moss composition analysis provides information on an average contamination within a few vegetation seasons. During our survey the measurements of radionuclide activity concentrations in P. schreberi transplanted from places relatively clean to heavily contaminated areas of Upper Silesia were carried out. An increase in the radionuclides activity concentrations in P. schreberi transplants may indicate not only deposition of the radionuclides itself, but also an influx of other pollutants. The results showed no relationship between the Pb-210 activity concentration and activity concentrations of Pb-214, Bi-214, also belonging to the uranium-radium decay series. The increased concentration of Pb-210 in P. schreberi may be the result of the radionuclide atmospheric deposition, which appears in the environment as a result of fossil fuels burning. Excess, allogeneic Pb-210 can be used as marker of environmental pollution. In the areas with its higher activity concentration increased pollution can be expected delivered, for example, by local industry. The Project received financial assistance from the funds of the National Science Centre, granted by force of the decision no. UMO-2013/09/B/NZ8/03340 (NCN).

14

Zawartość gamma radionuklidów pochodzenia naturalnego i sztucznego w glebach w powiecie puławskim

Isajenko K. A., Łukaszek-Chmielewska A., Bednarek M., Zielicz A., Smolarkiewicz M., Zwęgliński T.

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

|

2016

|

Nr 60 (4)

41--57

PL

Środowisko przyrodnicze ulega zanieczyszczeniom chemicznym, w tym także pierwiastkami promieniotwórczymi. Pewna grupa pierwiastków obecna jest w skorupie ziemskiej od momentu jej powstania i towarzyszy nam do dnia dzisiejszego. Pierwiastki te stanowią grupę naturalnych izotopów promieniotwórczych, do których zalicza się m.in. 40K, 238U, 235U i 232Th. Oprócz tego typu pierwiastków promieniotwórczych, środowisko przyrodnicze może ulegać skażeniom radioizotopami, takimi jak: 137Cs, 134Cs, 90Sr, 239+240 Pu lub 241Am itp., powstającymi wskutek działalności człowieka. Głównym źródłem ich obecności są awarie reaktorów jądrowych, przeróbka i składowanie paliwa jądrowego oraz zastosowanie metod jądrowych w przemyśle i medycynie. Zanieczyszczenia antropogeniczne środowiska przyrodniczego są jednym z głównych zagrożeń gleb Polski, ponieważ gleba pełni rolę buforu gromadzącego substancje chemiczne zarówno pochodzenia naturalnego, jak i antropogenicznego. Jak wynika z danych przedstawionych w Raporcie Rocznym z 2011 roku, przygotowanym przez Centralne Laboratorium Ochrony Radiologicznej (CLOR) średnie stężenie 137Cs w powierzchniowej warstwie gleby w Polsce jest ciągle podwyższone (powyżej 1 kBq/m2) i wynosi 1,93 kBq/m2 w związku z powyższym wymaga stałego monitorowania. W artykule przedstawiono zachowanie się radionuklidów naturalnych i sztucznych w glebach w okolicy Zakładów Azotowych Puławy. Do tej pory gleby na tym obszarze badane były pod kątem skażeń chemicznych, a nie radiologicznych. Omówiono również koncentracje radionuklidów naturalnych i sztucznych takich jak: 210Pb, 137Cs, 40K, 228Ac w pionowym profilu glebowym, metodą spektrometrii promieniowania gamma przy użyciu detektora germanowego. Na podstawie przeprowadzonych pomiarów stwierdzono, że stężenie sztucznego izotopu 137Cs w glebie jest niższe od zawartości naturalnych izotopów 40K czy 210Pb.

EN

The natural environment is exposed to pollution with chemical substances including radioactive elements. Certain class of elements has been in the earth’s crust since its formation and they have been up to this day. These elements form a group of natural radioactive isotopes which include 40K, 238U, 235U and 232Th. In addition to this type of radioactive elements the natural environment can be polluted with radioisotopes such as 137Cs, 134Cs, 90Sr, 239+240Pu or 241Am, which are released as a consequence of human activity. The main source of these elements are nuclear reactor incidents, processing and storing nuclear fuels as well as the use of nuclear methods in the industry and in medicine. The pollution due to human activity is one of the main hazards to the soil in Poland, because soil serves as a buffer which stores chemical substances both of natural origin and of anthropogenic origin. The data in the Annual Report from year 2011 prepared by the Centralne Laboratorium Ochrony Radiologicznej (CLOR, Central Laboratory for Radiological Protection) shows that the average concentration of 137Cs in the surface layer of soil in Poland is still elevated (over 1 kBq/m2) and equal 1,93 kBq/m2 thus requiring constant monitoring. That is why the paper describes the behavior of radionuclides of natural origin and of anthropogenic origin in the soil surrounding the Zakłady Azotowe Puławy (factory of nitrogen derivatives near Puławy, Poland). So far the soil in this area has been examined in terms of chemical pollution but not in terms of radiological pollution. In this article we present the results about the concentration of radionuclides of natural and anthropogenic origin such as 210Pb, 137Cs, 40K, 228Ac in the vertical soil structure using the method of gamma radiation spectroscopy and a germanium detector. Our data has shown that the concentration of the artificial isotope 137Cs in the examined soil is lower than the concentration of the natural isotopes 40K or 210Pb.

15

The natural radioactivity of the Carpathian national parks and radon evaluation

Maslyuk V. T., Symkanich O. I., Svatyuk N. I., Parlag O. O., Sukharev S. M.

Nukleonika

|

2016

|

Vol. 61, No. 3

351--356

EN

The results of the low-background gamma spectrometric measurements of protected mountain areas (Zacharovanyy Kray, Chorne Bahno, Ihthyological Preserve Rika and Uzhanskij National Natural Park) in the region of Primeval Beech Forests of the Transcarpathia, Ukraine, are presented. The distances between sampling points in a single protected area were in the range of 200–400 m in elevation of 300 m; probes were taken from the surface, from depth 20 cm and more than 50 cm. The proposed sampling scheme allows one to investigate the radionuclide concentration in protected area’s soils, their distribution on/near the mountain ridges and migration in depth (0–50 cm). We also investigate the infl uence the soils’ pH on the contents and the migration of nuclides. The obtained data allow us to study the statistical regularities between the sampling points along and down mountain ridges on the base of their radionuclide content. These results are important for evaluating the radon content/distribution and developing standards in the radionuclide content of the soil Carpathian region.

16

Bioaccumulative and bioindicative role of fungi in the environment

Moliszewska E., Dołhańczuk-Śródka A., Ziembik Z., Maculewicz D., Nagrodzka K.

Proceedings of ECOpole

|

2015

|

Vol. 9, No. 1

117--123

EN

Mycelial construction of mushrooms is considered as a good biomass for heavy metals binding as well as lots of elements, including toxic and radioactive ones. Between various fungi known to bind heavy metals, mycelium of Pleurotus spp. can be used in Cd indication and accumulation, by means of fungal biomass. In this work possible role of Pleurotus ostreatus in accumulation of radionuclides is presented. This is important because this fungus is one of broadly cultivated mushrooms, and it can grow as saprobic organism on various substrates. Naturally occurring fruiting bodies of P. ostreatus were used in studies as a potential marker of atmospheric radioactive pollution. The samples of fruiting bodies in different age (young, mature and old) were collected in the center of Opole. Measurements of the gamma radionuclides activity concentration in dried samples were carried out by means of a gamma-spectrometer with a germanium detector HPGe (Canberra) of high resolution. Potassium concentration in fruiting bodies was similar in each sample, though it was the lowest in the young specimen. Activity concentration of Cs-137 was also related with the age of the mushroom. The biggest concentration was determined in old specimen, while in the young and mature ones it was similar. In the mature and old mushrooms activity concentration of Pb-210 was lower than minimum detectable activity. Pb-212 was determined only in fruiting bodies of old specimen

PL

Grzybnia, szczególnie grzybów wielkoowocnikowych, dzięki zdolności do akumulowania metali ciężkich stanowi potencjalne źródło informacji o zanieczyszczeniu środowiska. Wśród nich należy wymienić boczniaka (Pleurotus osteratus), grzyba zarówno uprawnego, jak i występującego naturalnie. W pracy wykonano analizę zdolności bioindykacyjnych i biokumulacyjnych tego gatunku w stosunku do izotopów gamma-promieniotwórczych. Próbki P. osteratus w różnym wieku (młode, dojrzałe, starzejące) zebrano w naturalnym stanowisku, w centrum Opola. Aktywności izotopu K-40 były podobne we wszystkich badanych próbkach, przy czym najniższa koncentracja tego izotopu została stwierdzona w najmłodszych owocnikach. Izotop Cs-137 najliczniej występował w najstarszych owocnikach. Radioizotop Pb-210 znaleziono w młodych owocnikach, a izotop Pb-212 stwierdzono w starych owocnikach

17

Radioactivity of drilling cuttings from shale resources of the lower paleozoic Baltic Basin

Mykowska A., Rogala A., Kallas A., Karczewski J., Hupka J.

Physicochemical Problems of Mineral Processing

|

2015

|

Vol. 51, iss. 2

521--533

EN

Fractionated drilling wastes originating from shale gas exploration in the Baltic Basin in Polish Pomerania were subjected to measurements of mean activity concentrations of naturally occurring radioactive materials (NORMs). X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were used to understand the rock structure and texture. The activity concentration of radionuclides in bulk wastes and fractionated samples (latter obtained through a sieve analysis) was analyzed by using a gamma-ray spectrometer. After fractionation, three different size ranges were distinguished. Radiological indices were estimated by comparison with the levels recommended by the International Association of Oil and Gas Producers (OGP) and an equivalent absorbed dose was determined with respect to appropriated disposal of cuttings. The results showed that the drilling cuttings from the Ordovician period have a natural radioactivity level comparable to other rocks with the same lithology (potassium K-40 800-992 Bq/kg and thorium Th-232 23.3-30.8 Bq/kg) and they did not exceed acceptable levels of the total absorbed dose rate. The average absorbed dose rate in outdoor air one meter above the drilling cuttings was 54.1 nGy/h. The relation between particle size and natural radioactivity indicated that the concentration of radionuclides increased as the fractions size decreased.

18

Sorption of Sr-85 and Am-241 from liquid radioactive wastes by alginate beads

Oszczak A., Fuks L.

Nukleonika

|

2015

|

Vol. 60, No. 4, part 2

927--931

EN

The paper reports the adsorption of strontium(II) and americium(III) from aqueous solutions onto calcium alginate (CaA), barium alginate (BaA) and strontium alginate (SrA) beads. Adsorption process was studied in batch experiments as a function of the initial pH of the solution and the contact time. All sorbents were examined by the termogravimetric analysis (TG). Laboratory obtained spherical beads of CaA, BaA and SrA seem to be good metal sorbents from liquid radioactive wastes. A contact time of about 4 h and neutral pH of the initial aqueous solution have been proposed to be optimum conditions for Sr-85 and Am-241 removal from the contaminated solutions using alginate sorbents. Laboratory obtained beads of CaA, BaA and SrA are characterized by the decontamination factor (DF) equal to 85% for Sr(II) and 90% for Am(III).

19

On release of radionuclides from a near-surface radioactive waste repository to the environment

Gudelis A., Gorina I.

Nukleonika

|

2015

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Vol. 60, No. 3, part 2

551--555

EN

A closed near-surface radioactive waste repository is the source of various radionuclides causing the human exposure. Recent investigations confi rm an effectiveness of the engineering barriers installed in 2006 to prevent the penetration of radionuclides to the environment. The tritium activity concentration in groundwater decreased from tens of kBq/l to below hundreds of Bq/l. The monitoring and groundwater level data suggest the leaching of tritium from previously contaminated layers of unsaturated zone by rising groundwater while 210Pb may disperse as a decay product of 226Ra daughters.

20

Multibarrier system preventing migration of radionuclides from radioactive waste repository

Olszewska W., Miśkiewicz A., Zakrzewska-Kołtuniewicz G., Lankof L., Pająk L.

Nukleonika

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2015

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Vol. 60, No. 3, part 2

557--563

EN

Safety of radioactive waste repositories operation is associated with a multibarrier system designed and constructed to isolate and contain the waste from the biosphere. Each of radioactive waste repositories is equipped with system of barriers, which reduces the possibility of release of radionuclides from the storage site. Safety systems may differ from each other depending on the type of repository. They consist of the natural geological barrier provided by host rocks of the repository and its surroundings, and an engineered barrier system (EBS). The EBS may itself comprise a variety of sub-systems or components, such as waste forms, canisters, buffers, backfi lls, seals and plugs. The EBS plays a major role in providing the required disposal system performance. It is assumed that the metal canisters and system of barriers adequately isolate waste from the biosphere. The evaluation of the multibarrier system is carried out after detailed tests to determine its parameters, and after analysis including mathematical modeling of migration of contaminants. To provide an assurance of safety of radioactive waste repository multibarrier system, detailed long term safety assessments are developed. Usually they comprise modeling of EBS stability, corrosion rate and radionuclide migration in near fi eld in geosphere and biosphere. The principal goal of radionuclide migration modeling is assessment of the radionuclides release paths and rate from the repository, radionuclides concentration in geosphere in time and human exposure to ionizing radiation.