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In Rechna Doab, samples of the most common vegetation, perennial grass Desmostachya bipinnata (dab), were collected along with soil samples from 29 sites. Natural radioactivity of 226Ra, 232Th/228Ac and 40K was measured by using high purity germanium-based gamma ray spectrometer. Activity concentration levels of 226Ra, 232Th/228Ac and 40K in soil were found to be 46.8±6.2 (36.0–57.6), 61.4±5.9 (48.2–73.2) and 644.8±73.9 (537.7–868.4) Bq kg?1 (dry mass), respectively, and those in vegetation were 2.74±1.70 (1.00–6.39), 2.24±0.59 (1.56–2.61) and 172.72±113.37 (53.14–469.24) Bq kg?1 (dry mass), respectively. The measured values of the activity concentration in vegetation are comparable with some other international data. Calculated soil to vegetation transfer factors of 226Ra, 228Ac and 40K were 0.06±0.03 (0.02–0.14), 0.04±0.01 (0.03–0.04) and 0.26±0.16 (0.09–0.69). The mean outdoor absorbed dose rate in air for the area under study was determined as 8.22 nGy h?1 and the mean indoor absorbed dose rate in air was 11.52 nGy h?1. The total annual effective dose to the general public from the vegetation was found to be (0.02–0.16) mSv, which is below the recommended limit value of 1 mSv y?1 for the general public. The dab vegetation under study was found to be radiologically safe for the population and environment.  相似文献   
2.
Abstract

The results of the analysis of both natural (Th-232, U-238 and K-40) and artificial (Cs-137) radioactivity contained in samples collected during the 1989–90 and 1990–91 PNRA Scientific Campaigns in the Terra Nova Bay (Ross Sea) marine ecosystem, are presented in this paper. The data refers to samples of sea water, pack water, sediments and organisms belonging to demersal ichthyofauna (Pagothenia bernacchii, Chionodraco hamatus) and soft bottom macrofauna (Adamussium colbecki) collected in different coastal and off shore stations of the area investigated. Some sea water samples collected on the way to subAntarctic areas were also considered. The radiocontamination detected in sediments was correlated to the quantities of organic matter, organic carbon and nitrogen contained in the samples. Additionally, Cs-137 concentration factors were calculated for the different biological specimens and their anatomical components. Data values, with special consideration for anthropogenic Cs-137, are compared to results obtained from similar matrixes collected in the Northern Hemisphere in temperate waters before and after the accident at the Chernobyl nuclear plant.  相似文献   
3.
Beryllium-7 is a radionuclide produced in the upper atmosphere by cosmic-ray spallation with ions of carbon, oxygen and nitrogen. It is one of radionuclides that can be used to trace the fine particulate matter of 2.5-µm diameter (PM2.5) and smaller. In this work, 7Be was determined in leaves of 10 plant species collected from streets, parks and open land and in 5 consecutive rains over Alexandria, Egypt. 7Be levels were also measured in soil covered by each type of plant as well as in the nearest uncovered soil to be reference values to determine its intercepted amount and consequently PM2.5. The lowest interception, 17.7?%, was by Ficus elastica L., while Ficus retusa L. intercepted about 45?%. Radiologically, the annual effective dose due to the usage of Thymelea hirsute plant leaves as a medicine and Nicotiana glauca Graham for smoking were 0.013 and 0.66 µSv, respectively. The observed levels in rainwater indicated that 7Be decreased consecutively from 3.1 Bq kg–1 in the first rain to 0.71 Bq kg–1 in the last one during the 2016/2017 rain season. The wet deposition of 7Be is less than 1?% of its total deposition on the ground.  相似文献   
4.
Abstract

Dear Sir

With respect to the article “Collection and Analysis of Rainwater etc.” (Slanina et al., vol. 7, pp. 161-176), my remarks on this article (vol. 9, pp. 221-223) and the answer of Mr. Slanina (vol. 9, pp. 223-225), I should like to make my final remarks as follows.  相似文献   
5.
Tagungsberichte     
Like in other European countries, due to the accident at the Chernobyl nuclear power plant in 1986 the radioactive contamination level of the biological chain increased significantly in Hungary. The external and internal dose burden had a low-dose effect on plants ranging within the dose internal of stimulation and thus exhibiting a biopositive influence on the physiological functions.

Nach dent Unfall im Kernkraftwerk Tschernobyl im Jahre 19S6 slieg in Ungarn die radioaktive Kontamination der biologischen Kette erheblich an. Die externe und interne Strahlenbelastung hatte eine niedrigc Dosiswirkung auf Pflanzen, bewegte sich inncrhalb der Dosisspanne der Stimulation und wies somit einen biopositiven Einfluβ auf die physiologischen Funkionen auf.  相似文献   
6.
Twenty soil and 25 sediment samples were collected from the banks and bottom of the River Nile in the surroundings of biggest cities located close to it. Natural radioactivity concentrations of 226Ra, 232Th and 40K have been evaluated for all samples by means of γ spectrometric analysis. The radioactivity levels of soil and sediment samples fall within the internationally recommended values. Nevertheless, high natural background radiation zones are detected in the Kafr El-Zayat region due to the presence of a fertilizer factory, and in the Rosetta region due to the presence of black sand deposits. The absorbed dose rate, the γ index and excess life time cancer risk are calculated. High values for some of the radiation health parameters are detected in the Kafr El-Zayat and Rosetta regions representing a serious problem to public health because the soil and sediment are used as constructing material for buildings. Furthermore, the isotope analysis of uranium for representative collected sediment samples via α spectrometry showed average specific activities of 18.7?±?3.6, 0.087?±?0.0038 and 18.6?±?3.8 Bq kg–1 for 234U, 235U and 238U, respectively. In general, these values confirm the balance in the isotopic abundance of U isotopes.  相似文献   
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