Determination of coincidence summing correction factors for 22na point source

The coincidence summing effect plays an important role in HPGe spectrometry, especially at low source-detector distances, due to a large solid angle; therefore, the calculation of correction factors is necessary. The aim of the research described in this paper was to compare values of correction factors for a 22Na point source obtained using the GESPECOR software package (Monte-Carlo method) and experimentally obtained values. Measurements were performed using a semiconductor HPGe spectrometer and the point source axially positioned at nine different distances from the detector end-cap. For the purpose of determining correction factors, a system of equations was formed, which, besides nuclear data as the input parameters, uses the experimentally obtained values of the total count in the entire spectrum, as well as the counts in the full energy peaks. The system of equations was solved for each particular case and correction factors were determined. By comparing the results obtained using the experimental and Monte-Carlo method, it was found that the correction factors for the 22Na point source have discrepancies less than 3%. The significance of these discrepancies was also verified from a statistical point of view using a Student's t-test. © 2019 RAD Association. All rights reserved.Conference of 6th International Conference on Radiation and Applications in Various Fields of Research, RAD 2018 ; Conference Date: 18 June 2018 Through 22 June 2018; Conference Code:14955

Radon exhalation rate of some building materials common in Serbia

It is well-known that radon is the second important human carcinogen for lung cancer, after smoking. The major sources of indoor radon concentrations are soil and building material. Under certain conditions, a dose received from the inhalation of radon and its progenies can be higher than a dose received from the external exposure due to radium concentration in building materials. In this contribution, the results of the radon and thoron exhalation rate measurement from 9 commonly used building materials are reported. Exhalation rate measurements were performed with accumulation chamber method using active device for measurement of radon concentration. © 2019 RAD Association. All rights reserved.Conference of 6th International Conference on Radiation and Applications in Various Fields of Research, RAD 2018 ; Conference Date: 18 June 2018 Through 22 June 2018; Conference Code:14955

Determination of radionuclide concentrations in soil and black walnut leaves and fruit using gamma-ray spectrometry

This study showed that 137Cs concentrations in black walnut leaf and fruit, as well as in tinctures were below the detection limits. Concentrations of other radionuclides are lower than their concentrations in the soil, except for concentration of 40K in black walnut fruit, which objectively have more potassium due to the structure of the fruit. It indicates that the consumption of leaf and nut tinctureis absolutely safe, especially in relation to artificial radionuclides.X JUBILEE International Conference on Radiation in Various Fields of Research : RAD 2022 (Summer Edition) : book of abstracts; July 25-29, 2022; Herceg Novi, Montenegr

First steps towards national radon action plan in Serbia

Radon problem has a special attention in many countries in the world and the most of them have established national radon programmes. The radon issues in Serbia have not been approached in a systematic and organized way. Currently, there are many research groups and institutions working in radon field, and it is a good basis to integrate all these activities into a comprehensive national programme to define the strategic objectives and action plan for the next few years. Also, Serbia as a candidate for membership in the EU is obliged to harmonize its legislation, including the field of radiation protection in which the radon issues has an important role. In this report, a brief history of radon research, present status and plans for the future activity on radon issues in Serbia are presented. Regarding the long-term plans, the establishment and implementation of the Radon Action Plan with the primary goal of raising awareness about the harmful effects of public exposure to radon and implementing a set of measures for its reduction. In that sense, the synergy between the national, regional and local organizations responsible for public health and radiation protection must be achieved

Radon exhalation from fly-ash geopolymer mortar

Geopolymers are a type of alkali activated binders, inorganic aluminosilicate polymers with amorphous cross-linked structure. Fly-ash is produced in abundance during coal firing, and poses an environmental and health risk in untreated powder form. Fly-ash geopolymer presents a sustainable alternative to Portland cement, due to lower net greenhouse gas emissions. Presence of naturally occurring radioactive elements in fly-ash is one of the factors taken into account when estimating the safety of fly-ash based building materials. Radon, a radioactive noble gas originating from the decay of radium, can leave the material and contribute to internal dose in closed spaces, so radon exhalation is of special interest. Radon exhalation for a standard sample of fly-ash geopolymer mortar was measured

Investigation of the radon exhalation rate: an influence of humidity and a grain size

U radu je merena ekshalacija radona iz bigra iz Niške Banje poznatom po povišenoj koncentraciji 226Ra. Bigar zbog svoje velike poroznosti i visoke koncentracije radijuma je idealan materijal za testiranje parametara od kojih zavisi brzina ekshalacije. U radu je razmatrana zavisnost ekshalacije u odnosu na vlažnost kao i na sprašenost uzorka. Brzina ekshalacije je merena metodom zatvorene komore, a sama koncentracija radona aktivnim uređajem. Dobijeni rezultati ukazuju da brzina ekshalacije raste sa povećanjem vlažnosti uzorka i smanjenjem veličine zrna.In this contribution, radon exhalation rate from travertine originating from Niška Banja, Serbia was measured. This particular travertine, with a high 226Ra concentration and high porosity, is ideal for testing various parameters that can influence radon exhalation rate. The radon exhalation rate was investigated for different sizes of grains. Grain sizes were dived into 4 groups: 1) 2.1 - 1.6 mm, 2.) 1.6 - 1.2 mm, 3.) 1.2 - 0.7 mm i 4.) < 0.7 mm. Influence of the humidity on radon exhalation rate was also investigated. Samples with the smallest grain size were exposed to 3 different levels of humidity (dry sample, and two samples in which water content was around 10% and 20% of the mass of dry sample. An accumulation chamber method with an active device RTM1688-2 was used to estimate radon exhalation rate from continuous measurement of radon in the chamber. Obtained results indicate that radon exhalation rate is increasing with an increase of humidity of the sample and with an decrease of grain size

Radiological Analysis of Some Types of Medicinal Plants From the Gučevo Area and Estimation of Annual Effective Dose Due To Ingestation

U bogatoj flori Srbije uspeva veliki broj vrsta lekovitog bilja čiji se sastojci koriste u farmaceutskoj industriji i medicini, kako zvaničnoj tako i narodnoj. Pored toga lekovito bilje se u velikoj meri koristi u svakodnevnoj upotrebi kao neka vrsta napitka. Prirodni radionuklidi (radionuklidi uranovog i torijumovog niza kao i K-40) sastavni su deo naše životne sredine, a kao posledicu nuklearnih akcidenata imamo i prisustvo antropogenih radionuklida, pre svega Cs-137. Masovna upotreba lekovitog bilja predstavlja radijaciono opterećenje za široku populaciju, pa je zbog toga neophodan redovan monitoring. U ovom radu analizirano je 9 vrsta lekovitog bilja sa područja Gučeva (Zapadna Srbija). Specifične aktivnosti prirodnih radionuklida Pb-210 i K-40, kao i Cs-137 određene su merenjem svih uzoraka na poluprovodničkom HPGe spektrometru. Izračunate su godišnje efektivne doze usled ingestije za svaki izmereni radionuklid, i za dve starosne kategorije (uzrast od jedne godine i odrasla osoba). Svi proračuni su zasnovani na pretpostavci da se dnevno pije 200 ml čaja priprepremljenog korišćenjem određene lekovite biljake. Dobijene vrednosti za efektivnu dozu ingestije upućuju na zaključak da svakodnevna upotreba čajeva od lekovitih biljaka sa analiziranog područja ne predstavlja značajan radiološki rizik po zdravlje odrasle osobe, ali je neophodan oprez i obazrivost kada su u pitanju deca.In the rich flora of Serbia, there are a large number of medicinal plants types used in the pharmaceutical industry and medicine. There is also a large percentage of daily use of herbal teas as some kind of beverages. Natural radionuclides (radionuclides of the uranium and thorium series as well as K-40) are an integral part of our environment, and as a consequence of nuclear accidents we also have the presence of anthropogenic radionuclides, primarily Cs-137. The significant use of medicinal plants represent a radiological burden for the general population, so the regular monitoring is needed. In this work, 9 types of medicinal plants from the area of Gučevo (Western Serbia) were analysed. The specific activities of natural radionuclides 210-Pb i 40-K as well as Cs-137 were determined using a semiconductor HPGe spectrometer. Annual effective dose due to ingestion were calculated for each measured radionuclide, and for two age categories (one year old and adult). All calculations are based on the assumption daily consumption of 200 ml of herbal tea. The obtained values for the annual effective dose due to ingestion point to the conclusion that the daily use of medicinal plant teas from the analyzed area does not represent a significant radiological risk for the health of adults, but caution and prudence are necessary when it is about children.XXXII Simpozijum Društva za zaštitu od zračenja Srbije i Crne Gore, 4-6. oktobar 2023; Budva, Crna GoraProceedings: [https://vinar.vin.bg.ac.rs/handle/123456789/11602

Activity Concentrations of 210Pb, 137Cs, and 40K In Wild Mushrooms From Serbia and Their Effective Dose to Ingestion

Fourteen samples of nine different species were collected in the region of Fruška gora, the suburban areas of Belgrade, and the vicinity of Vlasina Lake (Serbia) have been analyzed from the radiological point of view. Specific activities of radionuclides 210Pb, 137Cs, and 40K were measured using a semiconductor HPGe spectrometer system in these wild mushroom samples. The activity concentrations of all measured dried wild mushrooms are for 210Pb: between 2.05 Bq/kg and 9.74 Bq/kg; for 137Cs: between < 0.2 Bq/kg and 19.3 Bq/kg; for 40K between 704 Bq/kg and 2530 Bq/kg. The total individual annual effective doses due to ingestion of 210Pb, 137Cs, and 40K radionuclides within a 0.5 kg dry mass of the wild mushrooms is between 3.99 µSv and 10.81 µSv, and are much lower than the recommended level for the public (1 mSv/y)

Internal Quality Control as an Important Part of Radiological Analysis of Environmental Samples Using Semiconductor HPGe Spectrometry

Ugalj kao fosilno gorivo sadrži brojne prirodne radioaktivne izotope koji pripadaju uranovom i torijumovom nizu, kao i 40K. Najviše se koristi u industriji, kao i u proizvodnji energije. Problem u vezi sa proizvodnjom energije iz uglja je takozvani „energetski otpad“, kao što su pepeo i šljaka, koji predstavljaju nesagorivi i nesagoreli ostatak pri sagorevanja uglja. Ako se pepeo i šljaka odlažu u životnu sredinu, može doći do povećanja i/ili preraspodele prirodnog sadržaja radionuklida. Da bi se utvrdio potencijalni uticaj „energetskog otpada“ na životnu sredinu, uzorci uglja, pepela i šljake iz termoelektrana „Nikola Tesla“ i „Kolubara“ mereni su poluprovodničkim HPGe spektrometrom u Laboratoriji za nuklearnu i plazmu fiziku Instituta „Vinča“. Kao rezultat ovih merenja, dobijene su koncentracije prirodnih radionuklida i veštačkog radionuklida 137Cs kao, što je prikazano u ranije objavljenim radovima. Prikazani rezultati su u saglasnosti sa istraživanjima sprovedenim širom sveta. Da bi se obezbedila tačnost i preciznost (pouzdanost) dobijenih rezultata merenja, u okviru Laboratorije uspostavljen je program kontrole kvaliteta (QC) i osiguranja kvaliteta (QA). Interna kontrola obuhvata proveru karakteristika poluprovodničkog HPGe spektrometra koji se koristi za merenje svih analiziranih uzoraka. Tačkasti izvori 60Co i 137Cs se koriste kao kontrolni izvori za proveru položaja pika, ukupne površine ispod pika, FWHM (puna širina na polovini maksimuma pika), FWTM (puna širina na desetini maksimuma pika) i odnos FWHM/FWTM. Pored navedenih karakteristika, redovno se kontroliše i ukupni odbroj prirodnog fona. Svaka od navedenih karakteristika može ukazati na neku nepravilnost u radu detektorskog sistema. Cilj ovograda je da se prikažu kontrolne karte ispitivanih karakteristika poluprovodničkog HPGe spektrometra korišćenog za merenje uzoraka uglja, pepela i šljake. Dobijene kontrolne karte predstavljaju važan alat na osnovu kojeg se analizira dugoročna stabilnost spektrometraeir daughter products, as well as 40K. It is widely used in industry as well as in energy pro-duction. The problems associated with the production of energy from coal is the so-called “energy waste”, such as ash and slag, which are incombustible and unburnt residue from combustion of coal. If ash and slag are released into the environment an increase and/or redistribution of natural radio-nuclide content can occur. To determine the potential impact of “energy waste” on the environment, samples of coal, ash, and slag from thermal power plant "Nikola Tesla" and "Kolubara" were meas-ured with a semiconductor HPGe spectrometer. Results of activity concentration of natural radionu-clides and artificial 137Cs in coal, slag and ash are presented in few previously published papers and obtained values are in accordance with similar worldwide investigations. o ensure the accuracy and precision (reliability) ofthe obtained measurement results, quality control (QC) and quality assurance (QA) program were established. Internal control includes check-ing of the characteristics of HPGe spectrometer used for measurement of all analysed samples. Point sources of 60Co and 137Cs are used as control sources for checking following characteristics: peak positions, net peak area, FWHMs (Full Width at Half Maximum), FWTMs (Full Width at Tenth Max-imum) and FWHM/FWTM ratios. In addition to the mentioned characteristics, the counting of back-ground is also regularly controlled. Each of the mentioned characteristics may indicate some irreg-ularity in the operation of the detector system and thus could influence reliability of performed activ-ity concentration measurements.The paper presents the control charts of the examined characteristics of the HPGe spectrometer used for measurements of coal, ash and slag samples. The obtained control charts indicate the long-term stability of the spectrometer and hence confirm accuracy and precision of measurement results.36. Međunarodni kongres o procesnoj industriji - PROCESING ′23 : zbornik radova ; 1-2. jun, Šaba

Radionuclide Content in Laundry Detergents Commercially Available on the Serbian Market and Assessment of Radiological Environmental Hazards

Laundry detergents are chemicals widely used in everyday life, and in numerous industry branches. In order to perceive the radiological aspect of environmental pollution by wastewater, the analysis of laundry detergents available on the Serbian market was undertaken. Laundry detergent samples were measured by means of gamma spectrometry and the results are presented in this paper. Analysis of the obtained activity concentrations showed that laundry detergents in Serbia mostly fulfill the international recommendation and requirements regarding the phosphate content. Besides that, the content of the detected radionuclides in laundry detergent samples indicates the minor radiological risk to the environment via wastewaters