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91.
The blocking anticyclone (BA) observed in the summer of 2010 over the European part of Russia led to enormous economical damage, substantially increased the mortality of the population, and had serious negative consequences for human health. Dynamic processes in the troposphere, i.e., wave trains, which could contribute to anticyclone formation and sustenance, are investigated. In order to study these wave trains, three-dimensional Plumb vectors have been calculated and analyzed. It is shown that, in June 2010, three wave trains propagated eastward in the troposphere over the Atlantics. The first two wave trains, having reached Europe, continued to propagate in eastern and southeastern directions. Only the third wave train, upon reaching Europe, continued to propagate toward the northeast and, on June 17–19, entered northwestern Russia. The anticyclone, which started to form on June 18 precisely in this region, subsequently developed into a stable BA observed over European Russia up to mid-August. The propagation direction of the wave trains could change due to the formation of a double structure of the zonal flow in the troposphere. The wave trains are revealed in the middle of June in regions with increased cloudiness over the northwestern part of the Atlantic Ocean and over the northwestern and northern parts of the central United States. Eastwardpropagating wave trains, which could contribute to the intensification of the corresponding BAs that brought anomalously high temperatures to European Russia, were also revealed in July and August of 2010 and 1972. The calculated 10-day backward trajectories are analyzed to determine the character of motions of air particles that penetrated into the anticyclone over the region of Moscow during the 2010 summer in the period of its development.  相似文献   
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The energy conservation law for the elliptical three-body problem is derived using an invariant relation corresponding to the Jacobi integral in the circular problem. The minimum-energy surfaces are constructed, which transform in the case of zero eccentricity into zero-velocity surfaces. Some astronomical applications of the results are considered. In particular, it is shown that Roche-lobe overflow displays pulsational behavior in the elliptical three-body problem.  相似文献   
94.
The fact that the energy-momentum tensor has nonzero vacuum expectation value in some space-times (the so-called back reaction) indicates a nontrivial thermodynamics of such vacua. A consequent thermodynamic analysis of the problem in Robertson-Walker space-times shows that, in the generic case, the number of the independent extensives is 2, in spite of the fact that the energy density is completely determined by the time-evolution of the geometry since the preparation of the vacuum state. The appearance of a second independent extensive seems to be in direct connection with the extra entropy term in theGeneralized Second Law of Bekenstein and Hawking.  相似文献   
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Theoretical and Applied Climatology - One of the most disastrous windstorms to take place over the Czech Lands occurred on the night of 26/27 October 1870. It is here analysed through the use of...  相似文献   
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The aim of this article is to inform about the spatial distribution of the lignite qualitative parameters and total lignite reserves in the Czech Part of the Vienna Basin—The South Moravian Lignite Coalfield (SMLC). The total reserves were estimated on the basis of several composed variant digital models of individual seams in four partial area of SMLC. Calculations of the reserves resulted from the identified spatial distribution of chemical-technological parameters obtained from the thousands analysis of samples taken from more than 4,000 exploration works. The basic model of the deposit was so-called geological model characterising genetic evolution of the deposit and defines the spatial positions of the coal seams. Subsequently developed variant economical models spatially define the selected areas by the quality of lignite expressed by the limits of ash yield. Based on the created models, it was found that in the past just 3–7 % (depending on the variant model) of the total lignite reserves SMLC had been extracted. The presented geological reserves are currently using the existing mining technologies only partially mineable.  相似文献   
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Mineralogy and Petrology - Tachylytes from rift-related volcanic rocks were recognized as: (i) irregular veinlets in host alkaline lava flows of the Kozákov volcano, Czech Republic, (ii)...  相似文献   
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A comparative study of the geological structure and evolution of the Curonian and Vistula spits representing large barrier-lagoon systems in the southeastern Baltic Sea reveals some geological and geomorphologic differences against the background of their general similarity. It is shown that morphological structures in the Vistula Spit are smaller. The grain-size analysis of the spit sediments demonstrates that eolian sands constitute all the structures of the spits down to the water level and below it (down to depths of 2 m), except for beaches and low lagoonal terraces. This means that the eolian relief on the maritime plain started forming when the sea level was approximately 4 m below its present-day position. Subsequently, they were growing beyond the wave influence. The sea-level rise resulted in the erosion of the coasts of the spits on both the sea and the lagoon sides and provided an intense landward transport of eolian material.  相似文献   
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