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61.
The changing chemical composition of cloud water and precipitation in the Western Sudety Mountains are discussed against the background of air-pollution changes in the Black Triangle since the 1980s until September 2004. A marked reduction of sulphur dioxide emissions between the early 1990's and the present (from almost 2 million tons to around 0.2 million tons) has been observed, with a substantial decline of sulphate and hydrogen concentration in cloud water (SO42− from more than 200 to around 70 μmol l− 1; H+ from 150 to 50 μmol l− 1) and precipitation (SO42− from around 80 to 20–30 μmol l− 1; H+ from around 60 to 10–15 μmol l− 1) samples. At some sites, where fog/cloud becomes the major source of pollutants, deposition hot spots are still observed where, for example, nitrogen deposition can exceed 20 times the relevant critical load. The results show that monitoring of cloud water chemistry can be a sensitive indicator of pollutant emissions.  相似文献   
62.
This work presents the results of a comparison between the global storm activity rate IRS and electric field intensity E0Z. The permanent analysis of the IRS may become an important tool for testing Global Electric Circuit models. IRS is determined by a new method that uses the background component of the first 7 Schumann resonances (SR). The rate calculations are based on ELF observations carried out in 2005 and 2006 in the observatory station “Hylaty” of the Jagiellonian University in the Eastern Carpathians (Kułak, A., Zięba, S., Micek, S., Nieckarz, Z., 2003. Solar variations in extremely low frequency propagation parameters: I. A two-dimensional telegraph equation (TDTE) model of ELF propagation and fundamental parameters of Schumann resonances, J. Geophys. Res., 108, 1270, doi:10.1029/2002JA009304). Diurnal runs of the IRS rate were compared with diurnal runs of E0Z amplitudes registered at the Earth's surface in the Geophysical Observatory of the Polish Academy of Sciences in Świder (Kubicki, M., 2005. Results of Atmospheric Electricity and Meteorological Observations, S. Kalinowski Geophysical Observatory at Świder 2004, Pub. Inst. Geophysics Polish Academy of Sciences, D-68 (383), Warszawa.). The days with the highest values of the correlation coefficient (R) between amplitudes of both observed parameters characterizing atmosphere electric activity are shown. The seasonal changes of R, IRS and E0Z are also presented.  相似文献   
63.
A variable-volume, head-dependent mine water filling model (MIFIM) has been utilized to simulate the post-abandonment flooding of the Siersza coal mine in the Upper Silesian Coal Basin of southern Poland. It is demonstrated that desaturated pore space in the aquifer adjacent to the mine comprises a significant component of the resaturable mine-related void. The model results are very sensitive to the value of this poorly constrained parameter. Nevertheless, the model successfully predicted the first appearance of mine water in an observation well and its subsequent rise. Despite this apparent success, it is concluded that such modeling approaches generally lack predictive power for mines in permeable, porous host rocks. As real monitoring data accumulate, however, such models can be calibrated and their utility increased.  相似文献   
64.
Ubiquitous post-Variscan dolomites occur in Zn–Pb–Cu veins at the Nízký Jeseník Mountains and the Upper Silesian Basin (Lower and Upper Carboniferous siliciclastics at the eastern part of the Bohemian Massif). Crush–leach, stable isotope (oxygen and carbon) and microthermometry analysis of the fluid inclusions in dolomites enable understanding the geochemistry, origin and possible migration pathways of the fluids. Homogenisation temperatures of fluid inclusions range between 66 and 148°C, with generally higher temperatures in the Nízký Jeseník Mountains area than in the Upper Silesian Basin. The highest homogenisation temperatures (up to 148°C) have been found near major regional faults and the lowest in a distant position or at higher stratigraphic levels. Highly saline (16.6–28.4 eq. wt% NaCl) H2O–NaCl–CaCl2 ± MgCl2 fluids occur in inclusions. Na–Cl–Br systematics of trapped fluids and a calculated oxygen isotopic fluid composition between ?0.9 and +3.0‰ V-SMOW indicate that the fluid was derived from evaporated seawater. Stable isotopic modelling has been used to explain stable isotopic trends. Isotopic values (δ13C = ?6.0/+2.0‰ V-PDB, δ18O = +15.5/+22.5‰ V-SMOW of dolomites) resulted from fractionation and crystallisation within an open system at temperatures between 80 and 160°C. Rock-buffering explains the isotopic composition at low w/r ratios. Organic matter maturation caused the presence of isotopically light carbon in the fluids and fluid–rock interactions largely controlled the fluid chemistry (K, Li, Br and Na contents, K/Cl, I/Cl and Li/Cl molar ratios). The fluid chemistry reflects well the interaction between the fluid and underlying limestones as well as with clay- and organic-rich siliciclastics. No regional trends in temperature or fluid geochemistry favour a fluid migration model characterised by an important vertical upward migration along major faults. A permeable basement and fractured sedimentary sequence enhanced the general nature of the fluid system. Fluid characteristics are comparable with the main post-Variscan fluid flow systems in the Polish (Cracow-Silesian ore district) and German sedimentary basins.  相似文献   
65.
Summary The paper deals with a study of the mean stress field (M) and its gradient (M/x) in uniaxially loaded two-dimensional models of small thickness with respect to other dimensions, in which two inhomogeneities, e.g., a circular opening and a linear slit have been made. Particular attention was paid to the stress field development in the treated models durin gthe change of the mutual geometric configuration of both the inhomogeneities in question. The problem was analysed theoretically by means of Muskhelishvili's potentials of the two-dimensional theory of elasticity. To compare the results of calculations, the schlieren method was used to visualize and record the studied gradients of stress fields in physical models. The results of the calculations were calibrated by laboratory tests. In this way the individual model situations were classified from the point of view of their resistance to the applied load.  相似文献   
66.
The different iron and manganese ore deposits of the Grythyttan-Hällefors area display an arrangement that reflects a systematic change in redox conditions from oxidic banded iron formation into highly reduced graphite-bearing slates. This phenomenon is explained by a facies model. The different environmental conditions are also held to be responsible for the geochemical differentiation of base metal deposits into Cu ores associated with minerals of Bi, Co, Mo, As, Zn, Pb, Au, and Pb-Zn-Ag ores associated with minerals of Sb, Mn, As, Sn, Cu. Spatial relationships between deposits of these two groups and certain iron and manganese deposits point to a common source of all metals, possibly connected with exhalative derivates from basic volcanism.
Zusammenfassung Die verschiedenen Eisen- und Manganerz-Bildungen des Grythyttan-Hällefors-Gebietes zeigen Verhältnisse auf, die einem systematischen Wechsel der Redoxbedingungen wiedergeben, von oxidischer Bändereisenerzbildung bis hin zu stark reduzierten graphitführenden Schiefern. Dieses Phänomen wird durch ein Fazies-Modell erklärt. Die unterschiedlichen Milieu-Bedingungen werden auch als Ursache für die geochemische Diferentiation unedler Metall-Ablagerungen in Cu-Erze angesehen, die mit Mineralien assoziiert sind, die Bi, Co, Mo, As, Zn, Pb, Au führen und in Pb-Zn-Ag-Erze in Verbindung mit Sb-, Mn-, As-, Sn- und Cu-führenden Mineralien. Die räumlichen Beziehungen zwischen Ablagerungen dieser zwei Gruppen und gewissen Eisen- und Mangan-Bildungen weisen auf eine gemeinsame Quelle aller Metalle hin, die möglicherweise mit exhalativen Derivaten eines basischen Vulkanismus in Verbindung steht.

Résumé Les différents gisements de minerais de Fe et Mn de la région de Grythyttan-Hällefors montrent une disposition qui réflète un changement systématique dans les ernolitions de réduction des formations rubanées de fer oxydé en phyllades graphiteux. Ce phénomène s'explique suivant un modèle faciétal. Les différentes conditions de l'environnement sont ainsi rendues responsables de la différentiation géochimique des gisements métallifères de base en minerais de Cu associés à des minéraux de Bi, Co, Mo, As, Zn, Pb, Au et des minerais de Pb-Zn-Ag associés à des minéraux de Sb, Mn, As, Sn, Cu. Des relations spatiales entre les gisements de ces deux groupes et certains gisements de Fe et Mn indiquent une source commune pour tous les métaux, en liaison possible avec des émanations du volcanisme basique.

Grythyttan-Hällefors , - : , , - . . , , Bi, , Mo, As, Zn, Pb, Au, , — , Sb, Mn, As, Sn, . , , , .
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67.
68.
We examine the possibility of probing dynamo action in mass-losing stars, components of Algol-type binaries. Our analysis is based on the calculation of non-conservative evolution of these systems. We model the systems U Sge and β Per where the more massive companion fills its Roche lobe at the main sequence (case AB) and where it has a small helium core (early case B) respectively. We show that to maintain evolution of these systems at the late stages which are presumably driven by stellar 'magnetic braking', an efficient mechanism for producing large-scale surface magnetic fields in the donor star is needed. We discuss the relevance of dynamo operation in the donor star to the accelerated mass transfer during the late stages of evolution of Algol-type binaries. We suggest that the observed X-ray activity in Algol-type systems may be a good indicator of their evolutionary status and internal structure of the mass-losing stellar components.  相似文献   
69.
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