215 research outputs found

    Concentrations of natural radionuclides in imported zirconium minerals

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    The natural radioactivity in imported zircon samples used as glaze for ceramic tiles in the ceramics industry has been presented in this paper. The measurements were made by gamma spectrometry with a high purity germanium detector. The average activity concentrations of 238U and 232Th determined in the measured samples (3250 Bq/kg, and 556 Bq/kg, respectively) are much higher than the concentrations found in the Earthā€™s crust. The activity concentration of 226Ra is also high in all analyzed samples, while 40K was not detected. The gamma index, I, the external hazard index, Hex, the internal hazard index, Hin, and the radium equivalent activity, Raeq, were calculated. Due to relatively high activity concentration level of uranium in imported zircon samples, specific regulations are necessary for zircon compound used in ceramic industry. It can be concluded that the investigated samples can be used as the component of ceramic glaze in the concentrations not above 3%

    Radioactivity Concentrations in Spa Waters - Dose Assessment

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    In this study 6 different spa water samples from Serbia, Hungary and Czech Republic were investigated in order to determine their radioactivity concentrations. These waters have been used on a large scale for medical and bathing purposes; for therapy, rehabilitation and recreation and also used for drinking, which is the most important. The obtained results showed that natural activity concentrations of alpha emitting radionuclides was within World Health Organization recommended levels and Serbian applicable regulations, but the gross beta activity exceed 1 Bq L-1 for some of the samples. Considering the fact that gross beta activity in four samples was higher than recommended levels, gamma spectrometric measurements were performed, in order to identify radionuclides which caused increase of the gross beta activity. It was found that K-40 was responsible for the elevated gross beta activity. Based on the obtained results the annual effective dose was calculated.3rd International Conference on Radiation and Applications in Various Fields of Research (RAD), Jun 08-12, 2015, Budva, Montenegr

    Radioactivity in raw materials used in ceramics industry

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    The natural radioactivity in zirconium samples used in the ceramics industry has been measured. One of the most important use of zircon is as opacifier for ceramic tiles. The measurements were made by gamma spectrometry with a high purity germanium detector (HPGe). The gamma index, I, the external hazard index, Hex and the internal hazard index, Hin, were calculated. The investigated samples can be used as one component in the recipe for the production of ceramics only if 3% of the samples used

    Cost-effectiveness of velmanase alfa vs. bone marrow transplantation or no causal therapy in patients with mild to moderate alpha-mannosidosis

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    Alpha-mannosidosis is an inherited rare disorder of mannose-containing oligosaccharides metabolism that is currently treated by enzyme replacement therapy (ERT), bone marrow transplantation (BMT), or supportive therapy (ST). However, the relative cost-effectiveness of these treatment options is yet unknown. Our study aimed to compare the cost-effectiveness of the treatment options for mild to moderate alpha-mannosidosis. The study is based on a modeling approach using a Discrete-Event Simulation model to generate and simulate the course of the disease under the influence of each of the treatment options: ERT, BMT, and ST. The model had a lifetime horizon and was made from the perspective of the Serbian Health Insurance Fund. Currently, available causal therapy of mild to moderate alpha-mannosidosis with velmanase alpha enzyme replacement is not cost-effective compared with supportive therapy (ICER = 941,587,152 RSD) or bone marrow transplantation (ICER = āˆ’398,412,755 RSD). Bone marrow transplantation can be cost-effective compared to supportive therapy (ICER = 6,032,689 RSD), but only if the willingness-to-pay threshold is increased to 9 gross domestic products (GDP) per capita per QALY gained. According to the current threshold, velmanase-alfa is not cost-effective compared to BMT or ST. To make alfa-mannosidosis therapy widely accessible to patients, criteria for assessing the cost-effectiveness of orphan drugs must include not only the absolute value of ICER but other aspects like equity weightings of QALYs, risk-sharing, reimbursement of severe forms of a disease only, or availability of dedicated funding

    Comparison of two different methods for gross alpha and beta activity determination in water samples

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    Measurement of the gross alpha and beta activity concentrations in various matrices is suitable as a preliminary screening procedure to determine whether further analysis related to specific radionuclide is necessary. In Serbia, according to current regulations, radioactivity concentrations in drinking water for gross alpha and gross beta should be LT 0.5 and LT 1.0 Bq L-1, respectively. The generally accepted methods for gross alpha and beta activity analysis of drinking water in different countries are: EPA 900.0 and ISO methods (ISO 9696, water quality - measurement of gross alpha activity in non-saline water - thick source method, and ISO 9697, water quality - measurement of gross beta activity in non-saline water). This paper describes comparison of preparations and measurement gross alpha and beta activity in bottled mineral waters as well as in tap waters in Serbia using two methods: EPA 900.0 with and without ash, and ISO methods. Concentration of total dissolved solids (TDS) in investigated water samples was determined. Based on obtained TDS, certain volume was evaporated. The instrumentation used to count the gross alpha and gross beta activities for both methods is alpha/beta low level proportional counter Thermo Eberline FHT 770 T

    The measurement of tritium in water samples with electrolytic enrichment using liquid scintillation counter

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    Tritium (3H) present in the environment decreased in the last decades and nowadays it has low activity concentrations. Measurement of low-level tritium activities in natural waters, e. g. in precipitation, groundwater, and river water requires special techniques for water pretreatment and detection of low-level radioactivity. In order to increase the tritium concentration to an easily measurable level, electrolytic enrichment must be applied. This paper presents the enrichment method performed by electrolysis in a battery of 18 cells, giving an enrichment factor of 5.84 (calculated from 59 electrolyses). The calculated mean values of the separation factor and enrichment parameter were 4.10 and 0.84, respectively. Results for tritium activity in precipitation and surface water collected in Belgrade during 2008 and 2009 are presented. The Radiation and Environmental Protection Department of the Vinča Institute of Nuclear Sciences, participated in the IAEA TRIC2008 international intercomparison exercise. The participation in the intercomparisons for any laboratory doing low-level 3H measurements in the waters is very important and useful. It is considered the best way to check the entire procedure and methods of the measurements and the reliability of the standard used. The analysis of the reported 3H activity results showed that all results for five intercomparison samples, for which electrolytic enrichment were applied prior to the 3H measurement, are acceptable

    Natural and artificial (90Sr) radionuclides in some carbonated mineral waters used in Serbia

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    A radiological characterization of 7 different carbonated mineral water samples collected in the local supermarkets in the area of Belgrade (produced in Serbia) was carried out. Analysis included determination of gross alpha and gross beta activities. The obtained results showed that the natural activity concentrations of alpha and beta emitting radionuclides in carbonated mineral water samples were within World Health Organization recommended levels, except for the Heba Strong and Kiseljak samples where the beta activity exceeds 1 Bq/L. For these two water samples gamma spectrometry analysis was performed as well as determination of 90Sr by oxalic method. The instrumentation used to count the gross alpha and gross beta activities, as well as for 90Sr, was a/b low level proportional counter Thermo Eberline FHT 770 T. Gamma spectrometric measurements were performed using a HPGe Canberra detector with a counting efficiency of 20%. The annual effective dose equivalent due to ingestion of investigated waters was calculated for age group >17, and obtained values are lower than 0.1 mSv recommended reference level. Finally, a comparison of the investigated waters with worldwide data was made. [Projekat Ministarstva nauke Republike Srbije, br. III43009

    Na0.44Mn02 as a cathode material for aqueous sodium-ion batteries

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    The application of rechargeable batteries is growing significantly and it became the nlost important field for largescale electric energy storage. While lithiuln-ion batteries (LIBs) have great commercial success, due to their large energy and power density, their application was limited because of the availability of lithiunl and its high cost. Sodiunl-ion batteries (SIBs) can be a promissing alternative due to the huge availability of sodium, its low price and similar intercalating electrochelnistry to LIBs. Among various Na-ion battery materials, low-cost and tunnel-type, Na0.44Mn02 (NMO) was regarded as one of the most pronlising cathode materials for sodium-ion batteries, because of its high theoretical specific capacity (122 rnA h g1) and good cyclability [2]. In this work, for the synthesis of NMO powder, rapid glycine-nitrate nlethod (GNM) was used, which, on the basis of the literature review, has not been used to synthesize this material so far

    Activity concentration of 210Pb in aerosol in Serbia in the period of 2014-2020 and the comparison between results from urban and rural sampling stations

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    Aerosol sampling and monitoring of naturally occurring and artificial radionuclides is readily performed within the frame of Environmental radioactivity monitoring in the Republic of Serbia. It provides information important for the preservation of the public health and the environment from the harmful effects of ionizing radiation. This type of monitoring has been performed in Institute of Nuclear Sciences Vinča for more than 30 years now. The radionuclides that are measured are: naturally occurring 210Pb, artificial radionuclide 137Cs and cosmogenic radionuclide 7 Be. Particle reactive radionuclides such as 210Pb and 7 Be have been used as atmospheric tracers for studying environmental processes such as cloud scavenging and precipitation [1], aerosol transit and residence times in the troposphere [2], and aerosol deposition velocities [3]. The fission product 137Cs is an indicator of anthropogenic pollution caused by nuclear weapon atmospheric tests and nuclear power plant accidents. Seasonal variation in 137Cs in air is an indicator of the stratosphere-troposphere exchange processes [4]. In most aerosol samples in later years, the activity concentration of 137Cs is below the minimal detectable activity and therefore it was not taken into the consideration in this paper. The activity concentration of 7 Be is dependent on the movements of large air masses and vertical mixing in the atmosphere and also was not discussed in this paper. In this paper, the activity concentration of 210Pb in aerosol samples, obtained over the period from 2014. to 2020., was discussed. Sampling is performed using constant air flow pumps and Whatman filter papers on 6 measuring stations distributed in various parts of the country. Three stations are in urban areas of cities of Belgrade, Vranje and Zaječar and other three are in rural areas (Palić and Zlatibor) or removed from the urban part of the city (Meteorological station in Vinča). The monthly composite sample from each sampling station was ashed at the temperature below 400o C. After ashing, the residue aerosol is measured on HPGe detectors using a standard gamma spectroscopy method [5]. The results for 210Pb are of the order of magnitude of 10-4 to 10-3 Bq/m3 . The activity concentration in all investigated samples shows temporal dependence with the maxima in the winter months and minima observed during the spring and summer. Also, the comparison between the results obtained from the rural and urban locations was performed in order to investigate the influence of the air pollution present in the urban areas on the activity concentration of 210Pb. The values, obtained at stations located in rural parts, ranged from (0.056 ā€“ 3.3) mBq/m3 , while for stations located in urban areas the range was from (0.125 ā€“ 2.9) mBq/m3 . It can be seen that from all the data that the activity concentration of 210Pb was lower in rural areas. Two outliers were observed at Palic station, located in the plane and along the path of the prevailing south ā€“ east wind, possibly bringing aerosols from Deliblatska pescara (Deliblato Sands) [6].IV International Conference on Atmospheric Dust : October, 4-7, 2021, Torre Cintola Conference Centre | MONOPOLI | Italy

    Radionuclide content in samples of berries

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    After the Chernobyl accident, the presence of artificial radionuclides in foodstuff, especially in berries (blueberries, cranberries etc.), was heightened. Legislative, presented in Rulebook on Radioactivity Control of Goods During the Import, Export and Transit (Official Gazette RS, 86/19 and 90/19), establishes the mandatory gamma spectrometry measurement of berries, while the limits of radionuclide content in these products is defined in the Rulebook on Limits of radionuclide content in drinking water, foodstuff, feedstuff, medicines, items of general use, building materials and other goods placed on the market (Official Gazette RS, 36/18). At the Radiation and Environment Protection Department of the Vinča Institute of Nuclear Sciences, measurements of the radionuclide activity in foodstuff are readily performed. In this paper, the results of the investigation of berries in the period of 2014 to 2021 are presented along with the amount of this produce that can be ingested by the various age groups without exceeding the annual effective dose limit of 0.1 mSv
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