Diurnal and spatial variations of radon and its influence on ionization of the nearground atmospheric layer

The most abundant and efficient source of air ionization in the lower layer of the atmosphere is radon. As an alpha emitter, radon plays cruciant role in the earth atmospheric electricity. Besides physical, radon and ions have a significant biological role concerning human health: radon is health hazard while the ions are beneficial ingredient of the air we breathe. Measurements were made using continual radon monitor Rad-7 and air ion counter CDI-06. Diurnal and spa¬tial variations of both atmospheric constitutens are mutually related and dependant mo¬stly on radon exhalation potential, meterological parameters, aerosol con¬cen-tra¬ti¬on and formation of temperature inversion layer. Indoor concentrations are re¬la¬ted to radon accumulation and partiallz influenced by external radon concentratio

Contents of phenolics and carotenoids in tomato grown under polytunnels with different UV-transmission rates

Tomato (Solanum lycopersicum L.) is among the economically most important vegetables in Europe, valued for its bioactive properties due to significant contents of vitamins, carotenoids, and phenolic compounds. In this study, the tomato cultivar Big Beef F1 was grown in the open field (OF) and under polytunnels in central Serbia during 3 years. Polytunnels were covered with two foils (both with 57% reduced photosynthetic active radiation, PAR) differing in UV-A and UV-B transmittance. The aim of our work was to determine the influence of light conditions on accumulation of phytonutrients (carotenoids and phenolics) in the peel and flesh of ripe tomato fruits. The amount of effective antioxidants, caffeic acid, and quercetin (phenolics with ortho-dihydroxy substitution) in the peel was the highest in tomato fruits grown in the OF (maximal PAR and UV-A and UV-B radiation). Moreover, the content of leaf epidermal flavonoids was the highest in the OF. The content of lycopene and beta-carotene in the flesh of tomato fruit was higher under the polytunnel with higher UV-transmittance. Our results showed that selection of the right light conditions (quality and intensity) for tomato production has a significant effect on the accumulation of beneficial phenolics and carotenoids

The indoor radon and thoron concentrations in schools of Skopje (Republic of North Macedonia) and Banja Luka (Republic of Srpska) cities measured by raduet detectors

Radon (222Rn) and thoron (220Rn) are natural radioactive gases, generated in the terrestrial materials. They are the main sources of public exposure to ionising radiation in indoor environment worldwide. Differences in half-lives of 222Rn (T1/2=3.8 d) and 220Rn (T1/2=55.6 s) lead to its different indoor behavior. Se¬ve¬ral studies of indoor 222Rn and 220Rn in Northern Macedonia have been per¬for¬med, starting with measurements in dwellings in 2008 and continuing with mea¬su¬re-ments in schools during 2012. The surveys in the Republic of Srpska began later (in 2011) with the simultaneous 222Rn and 220Rn measurements in the dwellings and schools of Banja Luka cities. This paper, as a result of our coop¬eration, su¬m-ma¬rizes the results and general conclusions obtained from 222Rn and 220Rn mea¬su-re¬ments in schools of capitals. In both cities, the measurements were made using Raduet - nuclear tracer detectors; deployed at distances: >0.5m (Skopje) and 0.2m (Banja Luka); and exposed in a period: March 2012 - May 2012 (Skopje) and April 2011 -May, 2012 (Banja Luka). Results for 222Rn and 220Rn concentrations in both cities have a log-normal distribution. The 222Rn geometric mean value of 71 Bq/m3 in Skopje are higher than in Banja Luka city (GM = 50 Bq/m3). Among other factors that affect 222Rn variations, this difference could be related to the different exposure time of detectors. Furthermore, the dispersion of the 222Rn results in each city expressed through geometric standard deviation is relatively low: GSD = 2.13 (Skopje) and GSD = 2.11 (Banja Luka) indicating re¬la¬ti-vely homogeneous data sets. The 220Rn concentrations in Banja Luka (GM = 51 Bq/m3) were higher than in Skopje (GM = 11 Bq/m3). It is obvious that in the case of 220Rn, the exposure pe¬ri¬od did not play a significant role. One of the reasons for this difference could be the position of the detectors as well as the different buil-ding materials in the sch¬o¬ols. On contrary, the dispersion of the 220Rn results in Skop¬je (GSD = 3.38) was greater than in Banja Luka (GSD = 2.07)

Thoron, radon and air ions spatial distribution in indoor air

Spatial distribution of radioactive gasses thoron (Tn) and radon (Rn) in indoor air of 9 houses mostly during winter period of 2013 has been studied. According to properties of alpha decay of both elements, air ionization was also measured. Simultaneous continual measurements using three Rn/Tn and three air-ion active instruments deployed on to three different distances from the wall surface have shown various outcomes. It has turned out that Tn and air ions concentrations decrease with the distance increase, while Rn remained uniformly distributed. Exponential fittings function for Tn variation with distance was used for the diffusion length and constant as well as the exhalation rate determination. The obtained values were similar with experimental data reported in the literature. Concentrations of air ions were found to be in relation with Rn and obvious, but to a lesser extent, with Tn

Measuring current state of radioactivity of air, water and soil in the city of Novi Grad, Republic of Srpska

Subject of this survey is measuring of background artificial and natural radioactivity of air, water and soil in the city of Novi Grad, Republic of Srpska. This is a first step of environmental monitoring of this area before opening of the nuclear waste material disposal nearby in Trgovinska gora in Croatia. Trgovinska gora is located not more than half kilometer beeline from the city of Novi Grad. Previous underground military ammunition repository is turned into nuclear waste disposal nearby natural border (river Una) between Croatia and Republic of Srpska. In order to be able to measure potential leakage of nuclear waste outside of disposal, we made background radioactivity measurements of 226Ra, 232Th, 40K, 238U, 235U, 137Cs, 210Pb, 90Sr, 3H, in the soil, water and mud. Also, we measured 222Rn in the soil and air and gamma dose rates. Measuring places were chosen upstream and two downstream in the city. Measuring results showed typical background concentration for this part of continental Europe

Contents of phenolics and carotenoids in tomato grown under polytunnels with different UV-transmission rates

Tomato (Solanum lycopersicum L.) is among the economically most important vegetables in Europe, valued for its bioactive properties due to significant contents of vitamins, carotenoids, and phenolic compounds. In this study, the tomato cultivar Big Beef F1 was grown in the open field (OF) and under polytunnels in central Serbia during 3 years. Polytunnels were covered with two foils (both with 57% reduced photosynthetic active radiation, PAR) differing in UV-A and UV-B transmittance. The aim of our work was to determine the influence of light conditions on accumulation of phytonutrients (carotenoids and phenolics) in the peel and flesh of ripe tomato fruits. The amount of effective antioxidants, caffeic acid, and quercetin (phenolics with ortho-dihydroxy substitution) in the peel was the highest in tomato fruits grown in the OF (maximal PAR and UV-A and UV-B radiation). Moreover, the content of leaf epidermal flavonoids was the highest in the OF. The content of lycopene and beta-carotene in the flesh of tomato fruit was higher under the polytunnel with higher UV-transmittance. Our results showed that selection of the right light conditions (quality and intensity) for tomato production has a significant effect on the accumulation of beneficial phenolics and carotenoids

Factors Affecting Indoor Radon Variations: A Case Study in Schools of Eastern Macedonia

The subject of this study is the radon concentrations variations, measured with a nuclear track detectors in a total of 58 premises in all 29 primary schools of 4 municipalities in the eastern part of the Republic of Macedonia. Despite a relatively small territory, the variability of radon concentrations proved to be significant. The geometric means (geometric standard deviations) of radon concentrations in the examined municipalities were in the range from GM=71 Bq/m3 (GSD=2.08) to GM=162 Bq/m3 (GSD=2.69), while for the entire region it was: GM=96 Bq/m3 (GSD=2.47). The influence of the geographical and geological features of the school site as well as the building characteristics on the radon variations were investigated. The analysis showed that type of municipality, building materials, basement and geology have significant effects and respectively describe 6\%, 16\%, 22\%, 39\% of the radon total variability