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Abstract  

It is suggested to spend some time in a cave for curing respiratory diseases. Some ascribe the healing effect partly to radon. In Hungary in the Hospital Cave of Tapolca the mean radon concentration shows 17 times difference in the winter and in the summer period. The change of the forced exhaled volume in 1 s (FEV1) values was examined measured by 1824 patients in this cave. By 70% of the patients the FEV1 value improved, by 30% it became worse but these were independent from the radon concentration of the cave. Therefore, radon concentration has no positive effect during the treatments performed in Tapolca.

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The aim of the present study is a better understanding of the distribution and formation of salt efflorescences by mineralogical examination. Dominant sodium sulphate and sodium chloride surface efflorescences were selected for investigation. 24 samples were collected between 1999 and 2005 from 16 sites. The soil types were solonchak and meadow solonetz.Basic soil and groundwater analyses were performed according to the standard methods. Minerals were determined by X-ray diffractometry and SEM combined with microanalysis. The evaporation experiments were carried out in a Sanyo Versatile 350 HT environmental test chamber.It was concluded that common sulphate salts form rare and unique mineral associations on salt affected soils in Hungary.Comparing the groundwater compositions and the mineral associations of surface efflorescences or that of precipitated evaporites of groundwaters, the conclusion can be drawn that groundwater composition is reflected much better by the mineral association of experimentally precipitated evaporates of the groundwater than by the mineral associations of surface efflorescences. These differences suggest that the soil matrix may have an effect on the crystallization of minerals (e.g. gypsum, thenardite) in the efflorescences. The differences also suggest that in the surface efflorescences the precipitation process does not come to the end in all cases (minerals with high solubility are missing).Concerning the data on groundwater level depths in case of different (sodium carbonate versus sodium sulphate and sodium chloride) efflorescences, there is a tendency of declining groundwater table in the sequence of these soils. This difference can be explained by the difference (increase) in the solubility of various salt minerals.It was recognized that the change in the major component of surface efflorescenes in time (i.e. the sodium carbonate and sodium carbonate chloride versus sodium sulphate efflorescences before and after 1998) can be explained by the decline of the groundwater level and by the decreasing hydromorphic influence in the lowland area during the 19th and 20th century.Finally it can be stated that the presented research — which mainly focused on mineralogical aspects — has contributed to the earlier knowledge on surface salt efflorescences, which was based only on their chemical composition.

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Abstract  

Manganese(II) chloride complexes with 3,4- and 3,5-lutidine have been prepared. The crystal symmetry and cell dimensions have been calculated on the basis of powder diffraction data. The compounds were characterised also by FT-IR spectrometry. The thermal decomposition of the complexes has been studied by thermogravimetry and DSC. By plotting densities vs. molar mass, the diagram obtained has correspondence to similar observations in other solid metal-lutidine complex systems.

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Agricultural goods obtained and produced in Hungary have played an important role in the markets of Western Europe. By utilizing the ecological potentials of the Carpathian Basin, local inhabitants are in the position to produce considerable food surpluses in addition to meeting their own demands. With agricultural production becoming more and more intensive in Hungary, the application of mineral fertilizers also started to increase slowly from the 1960’s. From the mid-1970’s a uniform sampling, soil testing and fertilization extension system was created together with its own institutional and laboratory testing network. The intensive use of mineral fertilizers in Hungary lasted from the mid-1970’s to the last quarter of the 1980’s, during which an average amount of 230 kg·ha -1 NPK fertilizer was applied. In this period the so-called “build-up” fertilization was applied in conformity with the improvement of all other elements involved in the production technology, which was also clearly expressed in the agro-political objectives of those days aiming to obtain higher yields. At that time the nutrient supply and nutrient base of soils in Hungary increased clearly, so the production technology could no longer limit higher yields. In 1990 agriculture changed fundamentally and radically in Hungary, and the same was valid for nutrient supplies as well. At the beginning of the 1990’s there was a sudden decrease in the level of mineral fertilizer application (to below 40 kg NPK active ingredients·ha -1 ), followed by a slow increase, which has reached the level of almost 70 kg·ha -1 by today. In the meantime the animal stock in Hungary has decreased and consequently the amount of manure has also fallen. All in all, the nutrient balance of Hungarian soils has always been negative since 1989. Due to the changes in its structure and ownership over the past twenty years or so, it has become very difficult to obtain reliable information about Hungarian agriculture. The Soil Resources Management General Partnership (in Hungarian: Talajerőgazdálkodás Kkt.) conducts extension work based on soil sampling and has a continuous flow of data on over thirty thousand hectares, beginning at the end of the 1970’s. Based on the analyses of these data it can be stated that the extra amount of nutrients over balance, applied during the period of replenishment (until the change in regimes) has been „removed” from the soil over the past fifteen years, consequently the Hungarian nutrient balance has become negative again. This kind of fertilization practice cannot be sustained in Hungary, as the maintenance of the production potential of Hungarian soils is far from being resolved at the moment; it poses risks to and questions sustainability, as well as it may cause a very serious competitive disadvantage to the country.

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The applicability of the chloroform fumigation extraction method was tested for detecting soil microbial biomass and p-nitrophenyl phosphate (pNP) for acid phosphatase activity to study their response to heavy metal pollution in the rhizosphere soil of planted willow (Salix sp.).   The experimental site was located in the Toka River Valley (North-East Hungary) along the riverbank that had been severely polluted by flooding. The river had transported heavy metal and arsenic ions from several heaps deposited imprudently near a historic lead and zinc mining site. A phytoremediation experiment was set up by planting willow trees with the aim of extracting toxic elements from the soil. A strong significant difference between the control and the metal-contaminated rhizosphere soils resulted much lower microbial biomass values in the polluted soils, which suggests disturbance in the organic matter transformation dynamics. A significant increase in acid phosphomonoesterase activity was determined in the soil due to the pollution. The phosphatase enzyme production of living organisms may be stimulated by the measured higher moisture content and significantly lower LE-soluble phosphorus content of the polluted soil samples. The correlation established between soil water content and phosphatase activity was positive (r = +0.85), while that between LE-P content and phosphatase activity was negative (r = -0.69). The most important stimulating effect was attributable to the lower available phosphorus content, resulting from the heavy metal (Pb, Zn) content of polluted soil. Both measured biological parameters therefore were suitable for indicating soil pollution, but the change was adverse, the biomass decreased, while phosphatase activity increased. Microbial biomass and phosphatase activity were not correlated, indicating the different account of ecological factors that alter the biological properties of a soil.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. Somlai, G. Szeiler, P. Szabó, A. Várhegyi, S. Tokonami, T. Ishikawa, A. Sorimachi, S. Yoshinaga, and T. Kovács

Abstract  

In the last few decades attention has been given to improve workplace conditions, primarily to reduce the different health risks. In the air that accumulates in underground workplaces radon may constitute one of the health risks. The radon concentration in the show cave in Tapolca is especially high in summer months, with the annual average in the year 2005 being 7227 Bq/m3, in 2006 8591 Bq/m3. The radon concentration was found to be independent on the location of the measurement. Its value was rather similar for working hours and for the total period. The hours spent in the cave by the workers depend on the number of visitors. The radiation dose, estimated on the basis of personal dosimeters, is significant for those working there especially, employed during the whole year. Taking into consideration the actual working hours and the equilibrium factor, F = 0.4, given in the literature, it approaches and even exceeds the dose limit of 20 mSv/year. With a well organized work schedule, as well as the employment of outside workers during the summer period, the dose limit of 20 mSv/year can probably be maintained. However, on the basis of recent measurements, the actual equilibrium factor was determined to be F = 0.5, which in turn means a further 25% increase in the dose effect.

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Abstract  

The production of 133Ba via the nuclear reaction 133Cs(p,n)133Ba on targets of CsF and CsCl has been investigated. Two methods to quantitatively separate 133Ba from the Cs target material, using AG 50W-X4 and AG MP-50 cation exchange resins, respectively, have been developed. Measured thick-target yield values are presented and some characteristics of the underlying excitation function have been inferred. For this purpose, calculations using the Geometry Dependent Hybrid model, as implemented in the code ALICE-IPPE, have been performed. Aspects of the production targetry developed as part of this study are also discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: I. Boros, G. Horváth, S. Lehel, T. Márián, Z. Kovács, J. Szentmiklósi, G. Tóth, and L. Trón

Abstract  

[11C]-labeled form of ten A2a adenosine receptor specific 8-styryl-7-methyl-xanthine derivatives ([11C]-caffeines) were synthesised by N-methylation of the corresponding 8-styryl-xanthine derivatives using [11C]-methyl iodide in optimized reaction conditions. The results show that the [11C]-methylations take place with excellent radiochemical yields (35–93%), and can be utilised easily in online preparations. These labeled ligands may facilitate the positron emission tomographic (PET) investigation of adenosine A2a receptors.

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Abstract  

A frequently used method in determining the radium concentration of water is the radon emanation method. When radon gas is transferred to the Lucas-cell usually CaCl2 is used to remove the water traces. When we measured the background of the system using ultra clear distilled water the results were astonishing. The detailed investigation has shown that the unwanted radon originated from the CaCl2, contained about 1000 Bq/kg of 226Ra. Depending on the time interval between two measurement, the radon deriving from the CaCl2 disturbed the measurements.

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Abstract  

222Rn and 226Ra concentration of 18 frequently visited and regularly used, consumed spring waters on the Balaton Uplands have been measured by radon emanation method and alpha-spectrometry. 222Rn concentration varied between 1.5-55 Bq/l while 226Ra concentration between -601 mBq/l. The expected dose, between 14.1-119 mSv/y, has been assessed from the value of concentration supposing a daily consumption of 1 liter.

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