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1.
The 26 December 2004 tsunami covered significant portion of a coastal zone with a blanket of potentially contaminated sediments. In this report are presented results on mercury concentrations in sediments deposited by the tsunami in a coastal zone of Thailand. Since the total mercury concentrations are insufficient to assess mercury mobility and bioavailability in sediment, its fractionation was applied. Sediments were sampled within 50 days after the event and analyzed by sequential extraction method. The procedure of sequential extraction involved five subsequent stages performed with solutions of chloroform, deionized water, 0.5 M HCl, 0.2 M NaOH, and aqua regia. The mean concentration of total mercury in sediments was 119 ± 50 ng g−1 dry mass (range 66–230). The fractionation revealed that mercury is mainly bound to the least bioavailable sulphides 75 ± 6% (range 62–86), organomercury compounds 14 ± 7% (range 4–26), and humic matter 9 ± 7% (range 1–27). The lowest contributions bring fractions of water-soluble mercury 0.8 ± 1.0% (range 0.1–3.6) and acid soluble mercury 0.9 ± 0.5% (range 0.2–2.1). Although, the total mercury content is similar in a reference sample and in the tsunami sediments, the highly toxic organomercury fraction contribution is higher in the latter. The results were compared with chemical and sedimentological properties of the sediments but no significant correlations were obtained between them.  相似文献   
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In a recent paper Ballersteros and Ragnisco (1998) have proposed a new method of constructing integrable Hamiltonian systems. A new class of integrable systems may be devised using the following sequence: , where A is a Lie algebra is a Lie–Poisson structure on R 3, C is a Casimir for is a reduced Poisson bracket and (A, ▵) is a bialgebra. We study the relation between a Lie-Poisson stucture Λ and a reduced Poisson bracket , which is a key element in using the Lie algebra A to constructing this sequence. New examples of Lie algebras and their related integrable Hamiltonian systems are given. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Tourist farms in Lower Silesia, Poland   总被引:1,自引:0,他引:1  
In view of the small size of most Polish farms, attempts have been made to encourage diversification into rural tourism. The paper examines the progress made in Lower Silesia which has good resources for domestic and international tourism. Thanks to the promotional work of the Agricultural Consultative Centres over a hundred farms are now providing services. They do not generate a large share of the farm income but business is expanding and some areas are becoming very popular. Thus a base has been established for future expansion. Further development depends on easier access to credit and government support for ecological agriculture. Better promotion is also needed to increase interest in rural tourism in Poland and attract more visitors from abroad. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The Kodzko Metamorphic Complex (KMC) in the Central Sudetes consists of meta-sedimentary and meta-igneous rocks metamorphosed under greenschist to amphibolite facies conditions. They are comprised in a number of separate tectonic units interpreted as thrust sheets. In contrast to other Lower Palaeozoic volcano-sedimentary successions in the Sudetes, the two uppermost units (the Orla-Googowy unit and the Kodzko Fortress unit) of the KMC contain meta-igneous rocks with supra-subduction zone affinities. The age of the KMC was previously assumed to be Early Palaeozoic–Devonian, based on biostratigraphic findings in the lowermost tectonic unit. Our geochronological study focused on the magmatic rocks from the two uppermost tectonic units, exposed in the SW part of the KMC. Two orthogneiss samples from the Orla-Googowy unit yielded ages of 500.4±3.1 and 500.2±4.9 Ma, interpreted to indicate the crystallization age of the granitic precursors. A plagioclase gneiss from the same tectonic unit, intimately interlayered with metagabbro, provided an upper intercept age of 590.1±7.2 Ma, which is interpreted as the time of igneous crystallization. From the topmost Kodzko Fortress unit, a metatuffite was studied, which contains a mixture of genetically different zircon grains. The youngest 207Pb/206Pb ages, which cluster at ca. 590-600 Ma, are interpreted to indicate the maximum depositional age for this metasediment. The results of this study are in accord with a model that suggests a nappe structure for the KMC, with a Middle Devonian succession at the base and Upper Proterozoic units at structurally higher levels. It is suggested here that the KMC represents a composite tectonic suture that juxtaposes elements of pre-Variscan basement, intruded by the Lower Ordovician granite, against a Middle Palaeozoic passive margin succession. The new ages, combined with the overall geochemical variation in the KMC, indicate the existence of rock assemblages representing a Gondwana active margin. The recognition of Neoproterozoic subduction-related magmatism provides additional arguments for the hypothesis that equivalents of the Teplá-Barrandian domain are exposed in the Central Sudetes.  相似文献   
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There is still no clear understanding of the specific interactions between coal and gas molecules. In this context sorption–desorption studies of methane and carbon dioxide, both in a single gas environment and gas mixtures, are of fundamental interest. This paper presents the results of unique simultaneous measurements of sorption kinetics, volumetric strain and acoustic emission (AE) on three tetragonal coal samples subjected to sorption of carbon dioxide and methane mixtures. The coal was a high volatile bituminous C coal taken from the Budryk mine in the Upper Silesia Basin, Poland. Three different gas mixtures were used in the sorption tests, with dominant CO2, with dominant CH4 and a 50/50 mixture.The experimental set-up was designed specially for this study. It consisted of three individual units working together: (i) a unit for gas sorption experiments using a volumetric method, (ii) an AE apparatus for detecting, recording and analysing AE, and (iii) a strain meter for measuring strains induced in the coal sample by gas sorption/desorption. All measurements were computer aided.The experiments indicated that the coal tested showed preferential sorption of CH4 at 2.6 MPa pressure and exhibited comparable affinities for CH4 and CO2 at higher pressures (4.0 MPa). The results of chromatographic analysis of the gas released on desorption suggested that the desorption of methane from the coal was favoured. The relationship between the volumetric strain and the amount of sorbed gas was found to be non-linear. These results were contrary to common opinions on the coal behaviour. Furthermore, it appeared that the swelling/shrinkage of coal was clearly influenced by the network of fractures. Besides, the AE and strain characteristics suggested common sources of sorption induced AE and strain.The present results may have implications for the sequestration of carbon dioxide in coal seams and enhanced coalbed methane recovery (ECBM).  相似文献   
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The main purpose of the research is to achieve fully automated approach for supplying multi-resolution databases with linear objects in each scale. Moreover, the proposed solutions maintain the repeatability and accuracy of output data wherever possible according to the input scale. These properties are achieved by keeping the minimal object dimensions as well as the appropriate data pre-processing, based on the classification of source points. The classification distinguishes three classes of points: constant (unchangeable), temporary, and inherited. These classes build a structure of cartographic control points. Based on these solutions, the authors proposed an algorithm for linear object simplification based on minimal object dimensions and cartographic control points. It was also confirmed that the simplification between constant points does not cause geometry discrepancies in relation to the global simplification of the whole line.  相似文献   
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In 1990 the Polish Geological Institute initiated geochemical mapping of the country aimed at determining the actual conditions of chemistry in the Earth's surficial environments (soils, water sediments, and surficial waters as well) and sea-floor deposits in the Polish economic sector of the Baltic Sea. The geochemical mapping on different scales covered the entire area of the country and selected more important urban agglomerations and industrial districts. Approximately 15,100 samples of soils, 16,200 samples of fresh water sediments, 14,600 samples of surface waters and 467 samples of marine deposits were collected and analysed. A list of geochemical atlases published by the Polish Geological Institute is presented. Investigation of the distribution of radionuclides (natural and artificial) has been done since 1992. Concentrations of U, Th, K, post-Chernobyl Cs and γ dose rate were measured. Approximately 20,000 points covering the whole country were measured. More detailed mappings were executed in the areas polluted by Cs.  相似文献   
10.
Song Tranh 2 hydropower plant and the reservoir containing backed up water are located in the Quang Nam province (Central Vietnam). The region experiences unusual seismic activity related to the reservoir impoundment, with earthquakes of magnitude up to 4.7. In result of cooperation between the Institute of Geophysics, Vietnam Academy of Sciences and Technology and the Institute of Geophysics, Polish Academy of Sciences a seismic network has been built to facilitate seismic monitoring of the Song Tranh 2 area. The network, operating since August 2013, consists of 10 seismic stations. Here we show that the network is sufficient for advanced data processing. The first results of monitoring of the earthquake activity in Song Tranh 2 area in the period between 2012 and 2014, especially the completeness of catalogs, study and comparisons between water level and the seismic activity suggest direct connection between reservoir exploitation and anthropogenic seismicity.  相似文献   
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