Zavisnost distribucije radionuklida U- i Th-serije, 40K i 137 Cs od fizičko-hemijskih zemljišta u sistemu zemljište-biljka

More than 70% of the total annual human exposures to ionizing radiation originate from natural sources of terrestrial and cosmogenic origin, while more than 50% arises from soil...Više od 70% ukupne godišnje doze jonizujućeg zračenja kojoj je izloženo stanovništvo potiče iz prirodnih izvora terestrijalnog i kosmogenog porekla, pri čemu više od 50% potiče iz zemljišta..

Distribution dependence of U and Th series radionuclides, 40K and 137Cs on physicochemical properties of soil in the soil plant system

Више од 70% укупне годишње дозе јонизујућег зрачења којој је изложено становништво потиче из природних извора терестријалног и космогеног порекла, при чему више од 50% потиче из земљишта...More than 70% of the total annual human exposures to ionizing radiation originate from natural sources of terrestrial and cosmogenic origin, while more than 50% arises from soil..

Zavisnost efikasnosti germanijumskih detektora od gustine uzoraka u spektrometriji gama zračenja

The effect of the density of environmental samples on the counting efficiency of Ge detectors used in gamma-spectrometry was studied. The dependence εff(ρ) was determined for two HPGe detectors (relative efficiencies 18% and 20%) using five radioactive standard reference materials (silicone resins, epoxy resin, milk powder, soil) with different matrix densities (0.45-1.22 g/cm3) in Marinelli beakers (V = 500 cm3). The dependence of efficiency vs. density was found to be linear and the regression parameters for energies in the range of 60-2000 keV were determined, too. The effect of variation in density on the counting efficiency of Ge detectors is dominant in the range of lower energies (60-600 keV) and de creases with energies in the higher energy range.Ispitivan je uticaj gustine uzoraka iz životne sredine na efikasnost brojanja germanijumskih detektora u spektrometriji gama zračenja. Zavisnost εff(ρ) određena je za dva HPGe detektora (relativnih efikasnosti 18% i 20%) za različite radioaktivne standardne referentne materijale (silikonske smole epoksi smolu, mleko u prahu, zemlju) različitih gustina (0,45-1,22 g/cm3) u Marineli posudama zapremine V = 500 cm3. Utvrđena je linearna zavisnost efikasnosti brojanja od gustine uzoraka pri čemu su određeni parametri linearne regresije za niz energija iz intervala od 60-2000 keV. Efekt promene gustina na efikasnost brojanja germanijumskih detektora dominantan je u intervalu nižih energija (60-600 keV) i smanjuje se sa porastom energije u intervalu viših energija

ANALYSIS OF 238U,226Ra, AND 210Pb TRANSFER FACTORS FROM SOIL TO THE LEAVES OF BROADLEAF TREE SPECIES

This analysis of 238 U, 226 Ra and210Pb trans fer fac tors from the soil to the leaves of dif fer ent na tive broadleaf trees at sites pre viously mod ified by ura nium pres ence and at the site of back-ground ra dio ac tiv ity lev els, was con ducted using data from a few available stud ies from the lit er ature. The broadleaf tree species Quercus ilex, Quercus suber, Euca lyp tus camaldulensis, Quercus pyrenaica, Quercus ilex rotundifolia, Populus sp. and Eu calyptus botryoides Sm. at the affected sites and Tilia spp. and Aesculus hippocastanum L. at the back ground site were in cluded in the study regardless of the de cid uous or evergreen or igins of the leaves. In the papers cited here, data about ba sic soil parameters: pH, to tal Ca [gkg–1], sand [%], and silt + clay [%] fractions were also available. All the col lected data of ac tiv ity con cen tra tion [Bqkg–1] dry weight in the soil (n=14) which was in the range: 22-6606 for238U, 38-7700 for226Ra, and 37-7500 for210Pb, and the tree leaves in the range: 2.7-137.6 for238U (n=10), 2.6-134.2 for226Ra (n=14), and 27-77.2 for210Pb (n=14), in di cated that it was nor mally dis trib uted af ter log-transformation. The present study was conducted under the hypothesis that biological dif fer ences between the examined broadleaf tree species have a lesser in flu ence on the trans fer factors of the investigated radionuclides from soil to tree leaves compared to the impact of the soil parameters and radionuclides ac tiv ity con cen tra tions in the soil. Con sequently, it was ex-amined whether 238 U, 226 Ra, and210Pb soil-to-leaves trans fer fac tor val ues for av erage broadleaf spe cies could be predicted sta tis ti cally in the first ap prox imation based on their ac-tiv ity con cen tra tion in the soil and at least one basic soil pa ram eter using mul ti ple lin ear re-gression. © 2022, Vinca Inst Nuclear Sci. All rights reserved

NATURALLY OCCURRING RADIONUCLIDES AND BASIC CHARACTERISTICS OF SOIL AND ASH SAMPLES NEARBY COAL–FIRED POWER PLANTS

Deposition of (fly and bottom) ash generated after coal combustion in the coal fired power plants (CFPP) in Serbia is carried out in active and passive lagoons. Ash waste mixed with water is directly transported to the lagoon currently active and the other one is passive in the stage of temporary inactivity for technical consolidation of ash and drainage and subjected to revegetation process using grass–legume mixtures with the purpose of creating plant cover. In order to obtain similarity, samples studied in this work were all taken from the area covered with grass which included: (1) soil close to CFPP (2 km) and (3) ash from the flat area of associated passive lagoon. Investigated sites were four power plants: TE “Kolubara” (TEK), TE “Morava” (TEM), TE “Nikola Tesla” A (Tent A) and B (Tent B). In order to analyse environmental implications of ash deposition in the surrounding area, basic characteristics such as texture, particle size distribution, pH value, organic matter and carbonate content were determined in the soil and ash samples. Simultaneously, 238U, 226Ra, 210Pb and 232Th activity concentrations were measured as it is known that after elimination of the organic component of the coal in the process of combustion naturally occurring radionuclides activity concentrations in the coal ash could be enhanced up to 10 times. Analyses of differences between soil and ash samples collected in this study showed that for one group of soils some changes of physical and chemical characteristics occurred compared to the rest of the soils. These changes were found to be related to the soil texture, percentages of clay size particles and 232Th/226Ra activity concentration ratios

Raspodela pristupačnih sadržaja mikroelemenata po dubini kultivisanog zemljišta

This paper presents a study of the profile distribution of available micronutrients Fe, Mn, Cu and Zn and radionuclide 137Cs in cultivated soil at the experimental field 'Radmilovac' (property of Agricultural Faculty, Belgrade University) in the vicinity of Vinča Institute of Nuclear Sciences. The soil belongs to the anthrosol class of anthropogenic soils according to FAO (2006). At first, the deep plowing was performed while preparing soil for planting peach trees followed by cultivation of soil for 12 years. All agricultural treatments at the experimental field ceased for three years. After that period, soil sampling was carried out. Contents of DTPA-extracted Fe, Mn, Cu and Zn were in the range of (mg kg-1): 5.8-41.6; 9.2-34.2; 1-7.6 and 0.2-1.3, respectively. Detected activity concentration (Bq kg-1) for 137Cs ranged from 1.8 to 35. It was noticed that distribution patterns of 137Cs radionuclide and available Cu and Zn along soil depth were very similar and they were analyzed by simple linear regression; mutual affinity for the soil organic matter might affect their distribution in soil. Contents of available Fe and Mn exhibited different, more constant distribution within a soil horizon.U ovom radu ispitivana je raspodela sadržaja pristupačnih mikroelemenata Fe, Mn, Cu i Zn i koncentracije aktivnosti proizvedenog radionuklida 137Cs u profilima zemljišta (dubine 080 cm) sakupljenih sa voćnjaka pod zasadom breskvi na oglednom školskom poljoprivrednom dobru 'Radmilovac' (Poljoprivredni fakultet, Univerzitet u Beogradu) u neposrednoj blizini Instituta za nuklearne nauke 'Vinča'. Zemljište pripada klasi antrosol antropogenih zemljišta prema međunarodnoj FAO (2006) klasifikaciji. Priprema zemljišta za sadnju bresaka izvršena je rigolovanjem, posle čega je usledila 12 godina duga nega voćnjaka. Uzorkovanje zemljišta izvršeno je tri godine nakon prestanka svih poljoprivrednih tretmana zemljišta na oglednom polju. Sadržaji pristupačnih mikroelemenata Fe, Mn, Cu i Zn (dobijeni ekstrakcijom sa rastvorom 0,005 M DTPA) nalazili su se u opsegu (mg kg-1): 5,841,6; 9,234,2; 17,6 odnosno 0,21,3. Detektovana koncentracija aktivnosti 137Cs u zemljištu (merena metodom gama-spektrometrije korišćenjem koaksijalnog HPGe-detektora) nalazila se u intervalu (Bq kg-1): 1,835. Uočeno je da su obrasci distribucije po dubini profila pristupačnih oblika Cu i Zn i radionuklida 137Cs bili veoma slični, a rezultati proste linearne regresione analize su pokazali da je uzajamni afinitet prema organskoj materiji zemljišta mogao da utiče na takvu njihovu distribuciju. Sadržaji pristupačnih mikroelemenata Fe i Mn, pokazali su da imaju drugačiju, uniformniju distribuciju po dubini ispitivanih profila zemljišta

Efficient Development of Green Emulsifier/Emollient-Based Emulsion Vehicles: From RSM Optimal Experimental Design to Abridged In Vivo Assessment

Since natural-origin, sustainable ingredients are preferred by modern consumers, novel emulsifiers and emollients keep entering the market. This study hypothesizes that a combination of in silico, instrumental tools and simplified sensory studies could be used to efficiently characterize emulsions in a shorter timeframe. A total of 22 rather simple o/w emulsions were prepared by a time/energy-saving emulsification process. A natural mixed emulsifier (Lauryl Glucoside/Myristyl Glucoside/Polyglyceryl-6 Laurate) and two emollients (both with INCI name C15–19 Alkane) were used. The performed D-optimal experimental design within the response surface method (RSM) significantly narrowed down the number of samples about to enter the stage of texture, friction and sensory studies to the samples comprising 30% of a respective Emogreen emollient and 2% or 3% of the emulsifier. The sample comprising 2% emulsifier/30% Emogreen® L15 showed significantly higher firmness (42.12 mN) when compared to the one with 2% emulsifier/30% Emogreen® L19 (33.62 mN), which was somewhat unexpected considering the emollients’ inherent viscosity values (4.5 mPa·s for L15 and 9 mPa·s for L19). The sample with 2% emulsifier/30% Emogreen® L19 managed to maintain the lowest friction, while the one with 3% emulsifier/30% Emogreen® L19 released its full lubricating potential in the second part of the measurement (30–60 s). The obtained results revealed the strengths and weaknesses of each formulation, narrowing down their possible applications in the early development stage

Seasonal variations of naturally occurring radionuclides and 137cs in the leaves of deciduous tree species at sites of background radioactivity levels

Activity concentration of natural radionuclides and 137Cs were studied in leaves of the deciduous trees. In the spring and autumn season, leaves were collected in the area of normal background radiation levels represented by city parks in a multi-year period (2002-2012). Measurements by means of gamma-ray spectrometry showed 226Ra and 210Pb seasonal accumulation in leaves, while 238U and 235U could be detected only in autumn. Difference between seasons was not found significant for 40K and 137Cs. The study of radionuclides transfer factors was conducted by analyzing its relationships with basic soil properties at the beginning and the end of the vegetation period. © 2019, Editura Academiei Romane. All rights reserved

Seasonal variations of naturally occurring radionuclides and 137cs in the leaves of deciduous tree species at sites of background radioactivity levels

Activity concentration of natural radionuclides and 137Cs were studied in leaves of the deciduous trees. In the spring and autumn season, leaves were collected in the area of normal background radiation levels represented by city parks in a multi-year period (2002-2012). Measurements by means of gamma-ray spectrometry showed 226Ra and 210Pb seasonal accumulation in leaves, while 238U and 235U could be detected only in autumn. Difference between seasons was not found significant for 40K and 137Cs. The study of radionuclides transfer factors was conducted by analyzing its relationships with basic soil properties at the beginning and the end of the vegetation period. © 2019, Editura Academiei Romane. All rights reserved

238U, 226Ra, 232Th and 40K distribution with soil depth in agricultural soil rigosol type and its relation with main soil properties

Distributions of natural gamma emitting radionuclides 238U, 226Ra, 232Th and 40K were determined in two soil profiles rigosol type under the peach-tree field: one from and second out of the peach-tree root zone. Radioisotope activities (Bq/kg) lie in the range of normal terrestrial gamma-radiation in soil [1]. It is found that variation in natural radionuclides activities along a soil depth of 0-80 cm is due to differences in main soil properties: pH-reaction, carbonates, humus, clay and sand contents confirmed by high correlation between them.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200