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Abstract  

The determination of iodate in rain-water by neutron activation analysis is described. Iodate is separated by anion exchange. The determination limit of I is 0.02 μg·L−1 for a 20 ml sample. The influence of the sea on the composition of rain-water is demonstrated by the analysis of coastal rain-water. The results indicate that inorganic iodine (I2 and IO 3 ) is enriched in filtered coastal rain-water relative to the composition of sea-water.

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Abstract  

The Chernobyl fallout was estimated in Emilia-Romagna, a Northeastern region of Italy. Nuclide composition of airborne and the time evolution of the radioactivity were investigated. The comparison of the activity ratio of103Ru to137Cs allows to conclude that Italy was not influenced by the first release. The trend of the total activity and137Cs percentage in rain water was very similar to those of air particulates. A calculation model to estimate137Cs deposition onto the ground has been developed and validated by comparison of the calculated and experimental values for soil samples. The activity range was 2–40 kBq ·m–2.

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Abstract  

Measurements of some selected radionuclides were carried out in rain waters collected from Ibaraki Prefecture, Japan, following the nuclear accident at Tomsk-7, Russian Federation, in April 1993. The concentrations obtained for artificial radionuclides were90Sr1.8 mBq l–1,137Cs0.1 Bq l–1,131I0.1 Bq l–1 and129I4 Bq l–1. Uranium (238U) concentrations in rainfalls in April 1993 were 6.3–39 ng l–1. These data were compared to control values obtained previously and there was no appreciable influence on the radioactivity levels in Japan after the Tomsk-7 accident. Since only limited data on the concentrations of129I and uranium in rain water are available, these new analytical results contribute to understanding the background levels for these nuclides.

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The effect of rainfall on crop fertilization factors, such as macronutrients and yield, were studied during a long-term field experiment on a calcareous sandy soil with low humus content in North Hungary at the Örbottyán Experimental Station of Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences from 1961 to 2004. At the time of the set-up of the experiment, in 1959, the soil’s ploughed layer had the following characteristics: pH (H2O) : 7.5–7.8, pH (KCl) : 6.9–7.1, humus content: 0.6–1.0%, clay content: 5%, CaCO 3 content: 3–7%, AL soluble P 2 O 5 and K 2 O content: 40–60 and 50–100 mg·kg −1 . The experiment included ten treatments in five replications, giving a total of 50 plots (35 m 2 each) arranged in a Latin square design. From the 1st to the 25th year the fertilization rates were 0, 50 and 100 N kg · ha −1 · year −1 ; 0 and 54 kg P 2 O 5 ha −1 · year −1 ; 0 and 80 kg K 2 O ha −1 · year −1 and their combinations. From the 26 th year on these rates were 0 and 120 kg N ha −1 · year −1 ; 0, 60 and 120 kg P 2 O 5 ha −1 · year −1 and 0, 60 and 120 kg K 2 O ha −1 · year −1 and their combinations. The major findings can be summarised as follows. At average rainfall years on the control plots without any mineral fertilization the rye yield in monoculture stabilised at a level of around 0.8 t · ha −1 (Table 3). The yield doubled (1.8–1.9 t · ha −1 ) in the N, NP and NK treatments while the full NPK doses gave the maximum yield of 2.1 t · ha −1 significantly (mean: 1.7 t · ha −1 ). Without mineral fertilization on the control plots in droughty and dry years yields of 0.7 t · ha −1 and 0.8 t · ha −1 were harvested. This was a 13% yield reduction in droughty years as compared with an average year. Yield depressions of 33, 16, 21 and 20% were caused by drought (dry and droughty years) in the N, NP, NK and NPK treatments. In wet year the yield was 0.9 t · ha −1 in the control plots, representing a yield grown of 12.5% compared with average years (0.8 t · ha −1 ). In the case of N, NP, NK nutrition the increase in the harvested main yield was 43.1% while NPK treatments led to yield increment of 36.9% only. In the very wet years the rye yield declined even more than in case of drought. The unfertilised plots yielded 25% less than in the average years. In the case of unfavourable nutrition (N, NP, NK) the decrease in the main grain yield was 32.8% and in the case of NKP plots the negative effects was 26.2%. Rye in monoculture has approx. 29.4% less tolerance of very wet years than to dry. This yield depression is in line of Márton et al. (2007) statement whereas the over-wet conditions could be resulted oxygen deficiency in the crop’s root zone. Depending on the nutrient supplies, significant quadratic correlations were observed between the rainfall quantity and the yield (Control: R=0.7489***, N: R=0.8974***, NP: R=0.8020***, NK: R=0.7370***, NPK: R=0.9047***, mean R2=0.8180; 66.9%) during the vegetation period. The increase in grain yield per mm rainfall ranged from 3.0 to 6.4 kg·ha −1 in the case of optimum rainfall supplies, while the quantity of rainfall during the vegetation period required for the production of 1 kg air-dry yield ranged from 1529 to 3360 litres in the case of maximum yield. Based on the meteorological database for the 44 years of the long-term experiment (1961–2004) the frequency of years in which the rainfall was optimum for various levels of nutrient supply was as follows: control: 2%, N: 7%, NP: 7%, NK: 9%, NPK: 7%, giving an average of 6% over the treatments. This suggests that the occurrence of optimum rainfall supplies and the possibility of achieving optimum yields in the rye production will decline in the future. Under two different arable site plant ecological conditions (rainfall quantity, NPK fertilization) the yield average of rye in monoculture on calcareous sandy soil (Őrbottyán) was 86% less than that achieved in a biculture (rye and potato) on acidic sandy soil (Nyírlugos).

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wells in public supplies, river water samples from Douro River, and sea water samples from Atlantic Ocean. Rain water was also collected in this Zone. There were also collected five samples of groundwater in mountain range of Estrela and four samples of

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Abstract  

As a consequence of the reactor-accident of Chernobyl on Tuesday 29 April 1986 the environmental radioactivity in Austria increased for above the level recorded before. Depending on the amount of precipitation the deposition of radioactive fallout showed great differences. Many water samples /rain water, lake water, swimming pool water, drinking water, underground water/ collected /during period of April 29 to May 30/ from Vienna, Lower Austria and Steiermark were analyzed for90Sr. The following concentrations in /nCi 1–1/ of90Sr was found: 8.69±2.3 for rain water, 0.09±0.12 for lake water, 0.08–0.18 for swimming pool, 0.04–0.13 for drinking water, 0.07–0.2 for underground water. The90Sr concentration was not higher than the maximal permissible /0.004–0.4 nCi 1–1/ except for rain water.

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Abstract  

Two simple methods, (1) isotope exchange method and (2) anion exchanger column method, are developed for the determination of chemical forms of radioiodine (iodide and iodate) in water samples. Using these methods, transformations of chemical forms of iodine in various water samples were studied. It was observed that iodate in rain water (unfiltered) and milk tended to change iodide form, whereas iodide was converted to iodate form in seawater and tap water. After the Chernobyl accident both chemical forms of131I (iodide and iodate) were found in rain water samples collected in Japan.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Osaki, Y. Tagawa, T. Chijiiwa, S. Sugihara and Y. Maeda

Abstract  

The35S content in atmospheric deposition, aerosol and rain water was determined about every 10 days for a year with7Be,32P and some stable elements. Average35S concentrations were 110 mBq·m−2·d−1 for atmospheric deposition, 0.078 mBq·m−3 for aerosol in surface air and 45 mBq·l−1 for rain water. The ratios of7Be/35S were abnormally low, although most of32P/7Be showed the reasonable values corresponding to the residence times from 10 to 60 days. The excess35S suggests an external source of35S or/and a faster cycle of35S than that of7Be and32P.

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Abstract  

This paper presents the results of the application of a fast rabbit system and a high thermal neutron flux to neutron activation analysis of selenium in environmental samples. The short-lived radionuclide77mSe, (17.5s) is used for analysis. Results are presented for selenium in sea-water and rain-water, in biological reference materials, in food-stuffs and milk powder, in human hair and human blood-serum.

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Abstract  

To determine trace copper in water samples such as tap and rain water, neutron activation analysis preceded by chemical preconcentration was developed, in which copper was concentrated by adsorption on activated carbon powder using 8-quinlinol as an adjunct. Short-lived66Cu and long-lived64Cu were used as analytical radionuclides. It was demonstrated that copper can thus be detemined at a μg l−1 (ppb) level.

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