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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.

Ensuring confidence in the results of laboratory measurements is an essential assignment regarding quality control. Therefore, taking actions in obtaining valid results is crucial for such a task. In this paper we present the results of the internal quality control of the HPGe detector system. The results were obtained during 2022, in the Laboratory for Nuclear and Plasma Physics of the “Vinca” Institute for Nuclear Sciences, Belgrade, Serbia. Given results show proper use of the detector system and prove the validity of the results.

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 spektrome, eir 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.

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).

Kontrola kvaliteta laboratorijskog procesa zauzima značajno mesto u svakodnevnom laboratorijskom radu. Obzirom na važnost, međunarodni standardi su propisali načine i zahteve za vršenje ovakve kontrole. Jedan od zahteva standarda ISO 17025 je obezbeđenje poverenja u rezultate merenja, koje se, između ostalog, može vršiti kontinuiranim praćenjem parametara karakterističnih za laboratorijsku metodu od interesa preko konstruisanja tzv. kontrolnih karti. U radu su prikazani rezultati troipogodišnje analize rada gamaspektrometrijskog sistema u Laboratoriji za nuklearnu i plazma fiziku INN „Vinča“. Merenja su vršena jednom nedeljno a kao kontrolni izvori korišćeni su tačkasti izvori Co-60 i Cs-137. Pored praćenja odbroja ispod pika, položaja pika, širine na polovini visine pika (FWHM), širine na desetini visine pika (FWTM), kao i njihovog međusobnog odnosa (FWTM/FWHM), praćen je i odbroj u fonu. Rezultati su pokazali da gamaspektrometrijski sistem ima zadovoljavajuću stabilnost u radu u dužem vremenskom periodu., Quality control of the laboratory process plays an important role in daily laboratory work. Due to its importance, international standards have issued the ways and requirements for performing such a task. One of the requirements of the ISO 17025 standard is to ensure confidence in the measurement results, which, among other things, can be done by continuously monitoring the parameters characteristic of the laboratory method of interest through the construction of the so-called control charts. The paper presents the results of a three-and-a-half-year analysis of the gamma spectrometric system measurements in the Laboratory for Nuclear and Plasma Physics of the INN "Vinča". Measurements were made once a week and point sources Co-60 and Cs-137 were used as control sources. In addition to monitoring the count below the peak, the position of the peak, the full width at half maximum (FWHM), the full width at tenth maximum (FWTM), as well as their mutual ratio (FWTM/FWHM), the count in the background was also monitored. The results show that the gamma spectrometric system has satisfactory stability over a long period of time.

This paper aims to estimate a potential radiological risk from different kinds of coals used for domestic heating in Serbia, by measuring the activity concentration of radionuclides and radon exhalation rate. The obtained radon mass exhalation rate ranges from (5.3 ± 3.1) mBqkg–1s–1 to (70.3 ± 9.4) mBqkg –1s–1 and was highest for lignite type of coal. It is estimated that coal stored in the basement could contribute up to 50 Bqm–3 of indoor radon concentration at the ground level. Activity concentrations of 226Ra, 232Th, 40K, 238U, 235U, and 210Pb in analysed coal samples agree with previously reported concentrations of coal used in Serbia. The values of radium equivalent concentration and external hazard index indicate that the used coal does not represent a significant radiation hazard.

This pa per aims to es ti mate a po ten tial ra dio log i cal risk from dif fer ent kinds of coals used for do mes tic heat ing in Ser bia, by mea sur ing the ac tiv ity con cen tra tion of radionuclides and ra don ex ha la tion rate. The ob tained ra don mass ex ha la tion rate ranges from (5.3 +/- 3.1) mu Bqkg-1s-1 to (70.3 +/- 9.4) mu Bqkg -1s-1 and was high est for lig nite type of coal. It is es ti mated that coal stored in the base ment could con trib ute up to 50 Bqm-3 of in door ra don con cen tra tion at the ground level. Ac tiv ity con cen tra tions of 226Ra, 232Th, 40K, 238U, 235U, and 210Pb in ana lysed coal sam ples agree with pre vi ously re ported con cen tra tions of coal used in Ser bia. The values of radium equivalent concentration and external hazard index indicate that the used coal does not represent a significant radiation hazard.

Gamma ray spectrometry with high purity germanium (HPGe) detector is one of the most widely used methods for environmental samples measurements. It is basically a non-destructive method and usually there is no need for the extensive sample preparation. True coincidence summing effect has a significant effect in gamma ray spectrometry analysis, especially in low source-to-detector geometry. Many authors have paid attention to this problem mainly by analyzing and determining coincidence summing correction factors for artificial radionuclides. However, the effect of true coincidence summing can significantly affect the result obtained by gamma ray spectrometry of environmental samples. Therefore, special attention should be paid to the determination of correction factors for coincidence summing of radionuclides from natural series (uranium, thorium and actinium series). Coincidence summing correction factors can be determined in several manners. Application of appropriate software packages is one of the most common. Software packages EFFTRAN and GESPECOR are among the most used ones. These software are based on Monte Carlo simulation. EFFTRAN is efficiency transfer code with semiempirical approach, whereas GESPECOR is dedicated code specifically tailored to solve most of the problems concerning gamma spectrometric measurements. The values of the correction factors depend on the detector geometry as well as the relevant data related to analyzed sample. The geometry of the detector implies the parameters of the detector itself (crystal dimensions, thickness of the dead layer, the thickness of the detector window). On the other hand, the relevant data related to analyzed sample includes dimensions of the container in which the sample is packed, sample density, chemical composition. The aim of this work is to compare coincidence summing factors obtained by using EFFTRAN and GESPEOR software in the case of p-type semiconductor HPGe detector with 30 % relative efficiency. Al

This paper aims to estimate a potential radiological risk from different kinds of coals used for domestic heating in Serbia, by measuring the activity concentration of radionuclides and radon exhalation rate. The obtained radon mass exhalation rate ranges from (5.3 ± 3.1) mBqkg–1s–1 to (70.3 ± 9.4) mBqkg –1s–1 and was highest for lignite type of coal. It is estimated that coal stored in the basement could contribute up to 50 Bqm–3 of indoor radon concentration at the ground level. Activity concentrations of 226Ra, 232Th, 40K, 238U, 235U, and 210Pb in analysed coal samples agree with previously reported concentrations of coal used in Serbia. The values of radium equivalent concentration and external hazard index indicate that the used coal does not represent a significant radiation hazard.

A. carotis communis i a. subclavia su glavni krvni sudovi za ishranu regije glave i vrata. A. carotis communis preko svojih završnih grana, a. carotis externe et interne u potpunosti ishranjuje predeo glave, a delimično i vrata. A. carotis externa ishranjuje veći deo vrata i skoro celu glavu sem mozga, unutrašnjeg uha, oka i očne duplje. Na svom putu daje šest bocnih i dve završne grane. A. carotis interna vaskularizuje mozak i čulo vida. Na bazi mozga daje svoje četiri završne grane koje zajedno sa zadnjim moždanim arterijama, završnim granama a. basilaris, grade na bazi mozga Wilisov arterijski šestougao (anastomoza unutrašnje karotidne arterije i potključne arterije). Daje više manjih bočnih grana za vaskularizaciju bubne duplje, trigeminalnog gangliona, hipofize i delova tvrde moždanice. Najveća bočna grana je a. ophtalmica. A. subclavia vaskularizuje delove vrata, mozga i grudnog koša, kao i ceo gornji ekstremitet. Na svom putu daje 5 bočnih i jednu završnu granu.

Lifetimes of low-lying states in 73Ga and 70,72,74Zn were measured using the Recoil Distance Doppler Shift (RDDS) method. These nuclei were produced in deep-inelastic reactions in inverse kinematics with a 208Pb beam impinging on a 76Ge target. Prompt γ rays were detected using the AGATA tracking array coupled to the VAMOS++ spectrometer. Lifetime of the 5/2- state in 73Ga, measured for the first time, provides additional evidence for the existence of a 1/2-, 3/2- ground-state doublet. The lifetimes of the 4+ states in 70,72,74Zn were remeasured in an attempt to understand the discrepancies observed between earlier measurements. Our results are in agreement with those of previous plunger experiments.