Applying of Monte-Carlo simulations for in-situ gamma spectrometry

Kako bi se dobile krive efikasnosti detekcije za In-situ merenja gama zračenja poreklom iz zemljišta, potrebno je izvršiti odgovarajuće Monte-Karlo simulacije. U simulacijama je korišćena gustina zemljišta od 1,046 g/cm3 , dok je elementalni sastav zemljišta u kojem se generiše gama zračenje bio: O - 47%, Si - 35%, Al - 8%, Fe – 3,9%, C – 2,1%, Ca – 1,4%, K – 1,3%, N – 0,6%, Mg – 0,6%, N – 0,1%. Matrica zemljišta je predstavljena cilindričnom zapreminom prečnika 1,5 m i debljine 0,5 m, iznad koje je na visini od 1 m postavljen germanijumski detektor. Razmatrane su homogene distribucije različitih radionuklida (Ra-226, Th-232, K-40) u matrici zemljišta. U simulacijama su dobijeni i analizirani odgovarajući gama spektri, koji uz podatke o simuliranim efikasnostima detekcije, omogućuju poređenje sa realnim eksperimentalnim merenjima i praktičnu primenu simulacionih rezultata.In this work, the Monte-Carlo simulations for In-Situ gamma spectrometry of soil were performed. The simulated gamma spectrum, originated from K-40, as well as from members of Th-232 chain, and daughters of Ra-226, was obtained. We obtained the corresponding detection efficiency curve for HPGe detector, which can be applied for In-Situ measurement of radionuclide concentration in soil, assuming uniform radionuclide distribution.Зборник радова : XXIX симпозијум ДЗЗСЦГ : Сребрно језеро, 27-29. септембар 2017. годин

Applying of Monte-Carlo simulations for in-situ gamma spectrometry

Kako bi se dobile krive efikasnosti detekcije za In-situ merenja gama zračenja poreklom iz zemljišta, potrebno je izvršiti odgovarajuće Monte-Karlo simulacije. U simulacijama je korišćena gustina zemljišta od 1,046 g/cm3 , dok je elementalni sastav zemljišta u kojem se generiše gama zračenje bio: O - 47%, Si - 35%, Al - 8%, Fe – 3,9%, C – 2,1%, Ca – 1,4%, K – 1,3%, N – 0,6%, Mg – 0,6%, N – 0,1%. Matrica zemljišta je predstavljena cilindričnom zapreminom prečnika 1,5 m i debljine 0,5 m, iznad koje je na visini od 1 m postavljen germanijumski detektor. Razmatrane su homogene distribucije različitih radionuklida (Ra-226, Th-232, K-40) u matrici zemljišta. U simulacijama su dobijeni i analizirani odgovarajući gama spektri, koji uz podatke o simuliranim efikasnostima detekcije, omogućuju poređenje sa realnim eksperimentalnim merenjima i praktičnu primenu simulacionih rezultata.In this work, the Monte-Carlo simulations for In-Situ gamma spectrometry of soil were performed. The simulated gamma spectrum, originated from K-40, as well as from members of Th-232 chain, and daughters of Ra-226, was obtained. We obtained the corresponding detection efficiency curve for HPGe detector, which can be applied for In-Situ measurement of radionuclide concentration in soil, assuming uniform radionuclide distribution.Зборник радова : XXIX симпозијум ДЗЗСЦГ : Сребрно језеро, 27-29. септембар 2017. годин

Investigations of possible correlations between radionuclides content and geochemical characteristics of Vojvodina soil

U ovom rаdu prikazani su rezultati istraživanja moguće korelаcije geohemijskih kаrаkteristikа zemljišta i sadržaja prirodnih rаdionuklida 238U, 226Ra, 232Th i 40K, kаo i radionuklida antropogenog porekla 137Cs u svim geomorfološkim jedinicama zemljišta na području Vojvodine. Tokom 2001. godine izvršen je detaljan monitoring radioaktivnosti zemljišta na 50 odabranih lokacija prema tipu zemljišta sa analizom mehaničkog sastava zemljišta i sadržaja humusa i pristupačnog fosfora i kalijuma. Kako bi se ispitao potencijаlni uticаj obrаde poljoprivrednog zemljišta i vremenskih uslovа nа migrаciju i distribuciju rаdionuklidа prisutnih u zemljištu, monitoring zemljišta je na istim lokacijama ponovljen 2010. godine. Glavni zaključak ovih istraživanja je da izmerene maksimalne koncentracije aktivnosti radionuklida: 238U (87 Bq/kg), 226Ra (44,7 Bq/kg), 232Th (55,5 Bq/kg) i 137Cs (29 Bq/kg) u profilu zemljišta dubine 30 cm ne ugrožavaju bezbednost proizvodnje hrane na ovom zemljištu. Utvrđena je najveća zavisnost koncentracije aktivnosti kalijuma 40K od sadržaja gline u poljoprivrednom zemljištu.In this paper, we performed, for the first time, detailed study of Vojvodina’s soil in order to explore possible correlations of soil geochemical characteristics and radionuclide activity concentrations. The aim of this study is to analyze the content of natural radioisotopes 238U, 226Ra, 232Th and 40K, as well as artificial radioisotope 137Cs in all soil types originated from the same parent material – loess. The sampling locations were selected so that they are proportionately represented all geomorphological units: two mountains, four loess plateaus, three loess terraces, four alluvial plains, two sandstone terrains. The process of genesis of soil and cultivation mode plays a dominant role on the characteristics of the soil. However intensive agricultural production and the use of high mineral fertilizers have caused that the same type of soil contains different concentrations of available phosphorus and radionuclides. Comparison of activity concentrations between different types of soil confirmed that the presence of clay mostly contributes to radionuclides content in the soil. The main conclusion is that measured maximal activity concentrations for 238U (87 Bq/kg), 226Ra (44.7 Bq/kg), 232Th (55.5 Bq/kg) and 137Cs (29 Bq/kg) at 30 cm depth could not endanger the safety of food production

Multivariate analysis application for geogeny radon potential prediction

Geogeni radonski potencijal koji izdvaja radon u podzemnim slojevima kao dominantan uzrok akumulacije radona u zatvorenim prostorijama i koji je nezavisan od ljudskog uticaja i vremenski konstantan u geološkim okvirima predstavlja glavni alat za iznalaženje radonom ugroženih područja. U nedostatku podataka za permeabilnost zemljišta za radon i malog broja merenja radona u zemljištu, upotrebljena je multivarijantna analiza velikog broja raspoloživih geohemijskih podataka, merenja radioaktivnosti zemljišta i koncentracija aktivnosti radona u zatvorenim prostorijama datih lokacija na području Vojvodine. Nekoliko uporedivih metoda iz ROOT okvira za analize softverskog paketa TMVA je korišćeno za analizu zavisnosti koncentracije radona u zatvorenom od mnoštva ulaznih varijabli. BDTG kao najpodobnija metoda je pokazala da su varijable sa najvećim uticajem na koncentraciju radona u zatvorenim prostorijama pored sadržaja ukupnog azota, koncentracije aktivnosti radionuklida u zemljištu na profilu dubine od 30 cm i sadržaj humusa i gline. Dobijeni rezultati pokazuju dobro slaganje sa nedavnim ispitivanjem emanacije radona iz zemljišta na području grada Novog Sada.The most dominant source of indoor radon is the underlying soil, so the enhanced levels of radon are usually expected in mountain regions and geology units with high radium and uranium content in surface soils. Laboratory for radioactivity and dose measurement, Faculty of Sciences, University of Novi Sad has rich databases of natural radionuclides concentrations in Vojvodina soil and also of indoor radon concentrations for the region of Vojvodina, Northern Province of Serbia. In this paper, we present the results of correlative and multivariate analysis of these results and geochemical characteristics of soil in order to estimate the geogenic radon potential. The correlative and multivariate analysis were done using Toolkit for Multivariate Analysis software package TMVA package, which uses several comparable multivariate methods for our analysis. The evaluation ranking results based on the best signal efficiency and purity, show that the Boosted Decision Trees (BDT) and Multi Layer Preceptor (MLP), based on Artificial Neural Network (ANN), are multivariate methods which give the best results in the analysis. The BDTG multivariate method shows that variables with the highest importance are radio-nuclides activity on 30 cm depth. Moreover, the multivariate regression methods give a good approximation of radon activity using full set of input variable

Multivariate analysis application for geogeny radon potential prediction

Geogeni radonski potencijal koji izdvaja radon u podzemnim slojevima kao dominantan uzrok akumulacije radona u zatvorenim prostorijama i koji je nezavisan od ljudskog uticaja i vremenski konstantan u geološkim okvirima predstavlja glavni alat za iznalaženje radonom ugroženih područja. U nedostatku podataka za permeabilnost zemljišta za radon i malog broja merenja radona u zemljištu, upotrebljena je multivarijantna analiza velikog broja raspoloživih geohemijskih podataka, merenja radioaktivnosti zemljišta i koncentracija aktivnosti radona u zatvorenim prostorijama datih lokacija na području Vojvodine. Nekoliko uporedivih metoda iz ROOT okvira za analize softverskog paketa TMVA je korišćeno za analizu zavisnosti koncentracije radona u zatvorenom od mnoštva ulaznih varijabli. BDTG kao najpodobnija metoda je pokazala da su varijable sa najvećim uticajem na koncentraciju radona u zatvorenim prostorijama pored sadržaja ukupnog azota, koncentracije aktivnosti radionuklida u zemljištu na profilu dubine od 30 cm i sadržaj humusa i gline. Dobijeni rezultati pokazuju dobro slaganje sa nedavnim ispitivanjem emanacije radona iz zemljišta na području grada Novog Sada.The most dominant source of indoor radon is the underlying soil, so the enhanced levels of radon are usually expected in mountain regions and geology units with high radium and uranium content in surface soils. Laboratory for radioactivity and dose measurement, Faculty of Sciences, University of Novi Sad has rich databases of natural radionuclides concentrations in Vojvodina soil and also of indoor radon concentrations for the region of Vojvodina, Northern Province of Serbia. In this paper, we present the results of correlative and multivariate analysis of these results and geochemical characteristics of soil in order to estimate the geogenic radon potential. The correlative and multivariate analysis were done using Toolkit for Multivariate Analysis software package TMVA package, which uses several comparable multivariate methods for our analysis. The evaluation ranking results based on the best signal efficiency and purity, show that the Boosted Decision Trees (BDT) and Multi Layer Preceptor (MLP), based on Artificial Neural Network (ANN), are multivariate methods which give the best results in the analysis. The BDTG multivariate method shows that variables with the highest importance are radio-nuclides activity on 30 cm depth. Moreover, the multivariate regression methods give a good approximation of radon activity using full set of input variable

Radioecology and population exposure to ionizing radiation - the first 55 years

U ovom radu dat je pregled radova prezentovanih u oblasti Radioekologije i izlaganja stanovništva na skupovima Društva za zaštitu od zračenja, počev od I jugoslovenskog simpozijuma o radiološkoj zaštiti u Portoroţu 1963. godine i zaključno sa XXIX Simpozijumom Društva za zaštitu od zračenja Srbije i Crne Gore odrţanom na Srebrnom jezeru 2017. godine. U radu je dat pregled aktuelnih tema, osvrt na razvoj metoda i tehnika merenja, kao i opšti trendovi razvoja i diferenciranja oblasti radioekologije uslovljenih dogaĎanjima u obuhvaćenom vremenskom periodu.This paper gives an overview of the papers in the field of radioecology and population exposure to ionizing radiation presented at the Radiation Protection Association symposia starting with the 1stYugoslav Radiation Protection Association symposium held in Portoroţ in 1963 and concluding with the 29thsymposium of the Society for Radiation Protection of Serbia and Montenegro held at Srebrno jezero in 2017. An overview of current topics, methods andmeasurement techniques development review, as well as general trends in the development and differentiation of the radioecology field due to different events in the covered period are presented.Proceedings: [http://vinar.vin.bg.ac.rs/handle/123456789/8681

Correlations between soil characteristics and radioactivity content of Vojvodina soil

During the years 2001 and 2010, the content of U-238, Ra-226, in K-40 and Cs-137 in agricultural soil and soil geochemical characteristics were measured on 50 locations in Northern Province of Serbia - Vojvodina. The locations for sampling were selected so that they proportionately represent all geomorphologic units in the region. The content of clay and humus varied within wide limits depending on soil type and influence the activity concentrations of radionuclides. In this paper we analyzed correlations between radionuclides content and geochemical characteristics of the soil. Possible influence of fertilizers on U-238 content in soil was discussed. The main conclusion is that measured maximal activity concentrations for U-238 (87 Bq/kg), Ra-226 (44.7 Bq/kg), Th-232 (55.5 Bq/kg) and Cs-137 (29 Bq/kg) at 30 cm. depth could not endanger the safety of food production. The process of genesis of soil and cultivation mode plays a dominant role on the characteristics of the soil. The most significant correlation was found between the activity concentrations of K-40 and clay content in agricultural soil

Radioactivity and measurements of sediment deposition rate of the Drenova reservoir (B&H)

This work presents the first estimate of the radioactivity and sediment deposition rate of the Drenova reservoir. The radioactivity and sedimentation rate were computed applying the 210Pb and 137Cs methods. Samples of 210Pb and 137Cs were taken from four boreholes drilled in the Drenova reservoir in June 2010. Vertical distribution of the natural and artificial radionuclides in four boreholes was examined using a gamma spectrometry measurement with HpGe detectors, Gamma X type (10 keV-3 MeV). Activities ranging from 122-8 Bq/kg were found for 210Pb, and from 140-0.8 Bq/kg for 137Cs. The sedimentation rate in the Drenova reservoir varied from 1.96 to 2.90 cm per year for unsupported 210Pb and 0.47 to 5.33 cm per year for 137Cs

Correlation analysis of the natural radionuclides in soil and indoor radon in Vojvodina, Province of Serbia

The most dominant source of indoor radon is the underlying soil, so the enhanced levels of radon are usually expected in mountain regions and geology units with high radium and uranium content in surface soils. Laboratory for radioactivity and dose measurement, Faculty of Sciences, University of Novi Sad has rich databases of natural radionuclides concentrations in Vojvodina soil and also of indoor radon concentrations for the region of Vojvodina, Northern Province of Serbia. In this paper we present the results of correlative and multivariate analysis of these results and soil characteristics in order to estimate the geogenic radon potential. The correlative and multivariate analysis were done using Toolkit for Multivariate Analysis software package TMVA package, within ROOT analysis framework, which uses several comparable multivariate methods for our analysis. The evaluation ranking results based on the best signal efficiency and purity, show that the Boosted Decision Trees (BDT) and Multi Layer Preceptor (MLP), based on Artificial Neural Network (ANN), are multivariate methods which give the best results in the analysis. The BDTG multivariate method shows that variables with the highest importance are radionuclides activity on 30 cm depth. Moreover, the multivariate regression methods give a good approximation of indoor radon activity using full set of input variables. On several locations in the city of Novi Sad the results of indoor radon concentrations, radon emanation from soil, gamma spectrometry measurements of underlying soil and geology characteristics of soil were analyzed in detail in order to verify previously obtained correlations for Vojvodina soil