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This paper highlights an experimental model proposed for the management of nuclear materials containing natural uranium and thorium salts, based on technical and legislative methods. The investigated nuclear materials originate from laboratory chemicals with expired validity, having as manufacturers companies specialized in the manufacture of laboratory substances such as: Merck, Chemapol, Sigma Aldrich, Bucharest Reagent. The experimental program refers to several issues of great importance in the waste and environmental management, such as: a) the processing of radioactive substances containing nuclear materials and radioactive waste represented by solid objects contaminated with radionuclides from the radioactive series of U-238 and Th-232; b) gamma dose rate measurement during handling and processing of open sources of ionized radiation; c) measurement of suspicious contamination of the operating personnel which handles the equipment, including the materials used in the processing of open sources of ionizing radiation; and d) the inventory of nuclear materials according to the chemical formula, the mass of chemical substance, the mass of the nuclear element in each container and type of packaging. For the good development of processing these open sources of ionizing radiation containing nuclear materials, the ALARA principle (As Low As Reasonably Achievable) was applied, which is fundamental to the principles of radiation protection. All the measurements for determining the gamma dose rate and suspicious contamination were performed with the aid of a CoMo 170 radiometric device produced by Nuvia Instruments Gmbh Germany, equipped with a 170x100 mm2 PL detector with zinc sulfide calibrated with the aid of C-14, Co-60, Cs-137, U-238 and Am-241 radioactive isotopes and an external probe containing a scintillating crystal with sodium iodide enriched with thallium calibrated with Cs-137. [ABSTRACT FROM AUTHOR]

In the present work natural radioactivity was investigated in 27 samples of meat (fish, pork, chicken) collected in the period 2014-2016 from Galati, Braila and Vrancea counties, Romania. Level of gross alpha activity, gross beta activity and the concentrations of 210Po, 210Pb, 238U, 232Th, 226Ra, and 40K were determined. The values of the activity concentrations (fresh weight) in meat samples ranged in the intervals: 9-1632 mBq kg−1 (gross alpha), 31-133 Bq kg−1 (gross beta), 15-62 mBq kg−1 (210Po), 7-28 mBq kg−1 (210Pb), 9-58 mBq kg−1 (238U), 5-19 mBq kg−1 (232Th), 18-126 Bq kg−1 (40K), 0.7-5.7 Bq kg−1 (226Ra). Although the highest effective dose per kg was calculated for fish samples (2.4 ± 0.3 μSv kg−1), the highest annual effective dose (47.5 ± 6.6 μSv year−1) has been found in case of pork meat consumption. [ABSTRACT FROM AUTHOR]

The measurements for gross alpha and gross beta activity represent the first step in the radiological characterization of drinking water. In this study it was determined the level of gross alpha and gross beta activity for the drinking water in Galati, Romania. 318 samples were collected during 2013 and 2014 from all the waterworks in Galati. In 2013 the gross alpha activity and gross beta activity ranged from 6.0 to 75.8 mBq L-1, and from 25.0 to 386.2 mBq L-1, respectively, while in 2014 the gross alpha activity and gross beta activity ranged from 6.0 to 85.2 mBq L-1, and 25.0 to 434.8 mBq L-1, respectively. Associating the gross alpha activity and gross beta activity with 210Po and 228Ra radionuclides, which are the most radiotoxic alpha and beta emitters, the annual effective dose due to water ingestion was calculated. The annual effective dose for adults ranged from 0.005 to 0.074 mSv y-1, and from 0.055 to 0.218 mSv y-1, associated with 210Po and 228Ra, respectively. These values were compared to the recommended value by the World Health Organization for annual effective dose (0.1 mSv y-1). [ABSTRACT FROM AUTHOR]

This work presents some results obtained for complex matrices with different uses in industry, environment and health (steels, metallurgical slag, lithium nitride) after irradiation with radioisotope X-ray primary beams and electron beams and recording of corresponding energy dispersive X-ray spectra. Characteristic X-ray spectra highlight the presence of major and trace elements in the multi-elemental samples, such as As, Ga, K, Ca, Cr, Mn, Ni, Cu, Fe, Co, Pb and Zn in energy dispersive X-ray fluorescence (ED-XRF ) and C, O, S, P, Si, Ca, Na, K, La, Ce, Nd, Ga, Mo, Pr, Rh, Sm, Sn, Mg, Al, Ti, V, Cr, Ni, Cu, Mn, Fe, Co, As and Zn in scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX). Extension of the work will be done employing SEM-EDX for impurity analysis in selected samples of Li-N and B-N systems synthesized at different pressures, within the Romanian-Russian joint project JINR Dubna between Frank Laboratory of Neutron Physics (FLNP) of Joint Institute of Nuclear Research (JINR) at Dubna, Russia, and Physics Division within the Department of Chemistry, Physics and Environment, Faculty of Sciences and Environment, "Dunărea de Jos" University of Galati. [ABSTRACT FROM AUTHOR]

Abstract: Instrumental neutron activation analysis (INAA) was applied to determine elemental concentrations in some fish species collected frome the Romanian sector of Danube River at km 1049, near the entrance in Romania (Carassius auratus gibelio, Ctenopharingodon idella, Rutilus rutilus and Silurus glanis) and km 630 (Acipenser ruthenus). Concentration values of 32 elements (Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Lu, Na, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Zn and Zr) in calcined fish samples were obtained based on long half-life radionuclides. Bioaccumulation factors (BAF) in fresh fish relative to Danube water (km 1049) were assessed and compared with literature data. [Copyright &y& Elsevier]

This study aimed to investigate the interaction parameters of antioxidant molecules in some spices and vegetables with gamma radiation. At first, mass attenuation coefficients (MACs, cm2/g) of gingerol, rosmarinic acid, quercetin, curcumin, eugenol, piperine, allicin, and capsaicin molecules were determined at the photon energies (13–1332 keV) emitted from the radioactive isotopes Am-241, Ba-133, Co-60, and Cs-137 with the help of the EpiXS and WinXCOM programs. The smallest and largest MAC values were found as 1.20 and 8.48 cm2/g at 13 keV and 0.059 and 0.058 cm2/g at 1332 keV for eugenol and allicin, respectively. It was observed that both results support each other. Using the MAC values, the effective atomic number and electron density (Zeff and Neff) values of the molecules were derived. The Zeff values for gingerol and allicin were obtained in the range of 5.79–3.40 and 13.85–4.53, respectively. The variation of the buildup factors of antioxidants in the range of 0.015–15 MeV depending on the chemical composition and penetration depth were also examined. It was noticed that the photon accumulation was the lowest in allicin and the highest in gingerol and eugenol. The results obtained from this study will make an essential contribution to dose calculations in food irradiation studies. [ABSTRACT FROM AUTHOR]

Natural radioactivity, radiological hazard, and petrological studies of Homrit Waggat granitic rocks, Central Eastern Desert, Egypt were performed in order to assess their suitability as ornamental stone. On the basis of mineralogical and geochemical compositions, Homrit Waggat granitic rocks can be subdivided into two subclasses. The first class comprises granodiorite and tonalite (I-type) and is ascribed to volcanic arc, whereas the second one includes alkali-feldspar granite, syenogranite, and albitized granite with high-K calc alkaline character, which is related to post-orogenic granites. 238U, 226Ra, 232Th, and 40K activities of natural radionuclides occurring in the examined rocks were measured radiometrically using sodium iodide detector. Furthermore, assessment of the hazard indices—such as: annual effective dose (AED) with mean values (0.11, 0.09, 0.07, 0.05, and 0.03, standard value = 0.07); gamma radiation index (Iγ) with mean values (0.6, 0.5, 0.4, 0.3, and 0.14, standard value = 0.5); internal (Hin) with mean values (0.6, 0.5, 0.4, 0.3, and 0.2, standard value = 1.0); external (Hex) index (0.5, 0.4, 0.3, 0.24, and 0.12, standard value = 1.0); absorbed gamma dose rate (D) with mean values (86.4, 75.9, 53.5, 43.6, and 20.8, standard value = 57); and radium equivalent activity (Raeq) with mean values (180, 154, 106.6, 90.1, and 42.7, standard value = 370)—were evaluated with the knowledge of the natural radionuclides. The result of these indices falls within the acceptable worldwide limits. Therefore, we suggest that these rocks are safe to be used in industrial applications. [ABSTRACT FROM AUTHOR]