Characteristic frequencies of seismic attenuation due to wave-induced fluid flow in fractured porous media   总被引：2，自引：0，他引：2  

Miroslav Brajanovski  Tobias M. Müller  Boris Gurevich 《Geophysical Journal International》2006,166(2):574-578

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Two-stream approximation for rapid modeling the light pollution levels in local atmosphere     

Miroslav Kocifaj 《Astrophysics and Space Science》2012,338(2):301-307

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Thermal behavior of almandine at temperatures up to 1,200°C in hydrogen     

Claudia?Aparicio  Jan?FilipEmail author  Henrik?Skogby  Zdenek?Marusak  Miroslav?Mashlan  Radek?Zboril 《Physics and Chemistry of Minerals》2012,39(4):311-318

The thermally induced reductive decomposition of a natural near end-member almandine [^VIII(Fe_2.85Mg_0.11Ca_0.05Mn_0.02)^VI(Al_1.99)^IV(Si_2.99)O₁₂] and possible hydrogen diffusion into its structure have been carried out at temperatures up to 1,200°C, monitored by simultaneous thermogravimetric analysis and differential scanning calorimetry (DSC), infrared and ⁵⁷Fe Mössbauer spectroscopy and X-ray powder diffraction. Below 1,000°C, evidence for hydrogen diffusion into almandine structure was not observed. At temperatures above 1,000°C, reductive decomposition sets in, as displayed by a sharp endothermic peak at 1,055°C on the DSC curve accompanied by a total mass loss of 3.51%. We observe the following decomposition mechanism: almandine + hydrogen → α-Fe + cristobalite + hercynite + water. At higher temperatures, fayalite and sekaninaite are formed by consecutive reaction of α-Fe with cristobalite and water, and cristobalite with hercynite, respectively. The metallic α-Fe phase forms spherical and isolated particles (~1 μm).  相似文献   

An analysis of the FIR/RADIO continuum correlation in the small Magellanic cloud     

Howard Leverenz  Miroslav D. Filipović 《Astrophysics and Space Science》2013,343(1):301-317

The local correlation between far-infrared (FIR) emission and radio-continuum (RC) emission for the Small Magellanic Cloud (SMC) is investigated over scales from 3 kpc to 0.01 kpc. Here, we report good FIR/RC correlation down to ～15 pc. The reciprocal slope of the FIR/RC emission correlation (RC/FIR) in the SMC is shown to be greatest in the most active star forming regions with a power law slope of ～1.14 indicating that the RC emission increases faster than the FIR emission. The slope of the other regions and the SMC are much flatter and in the range of 0.63–0.85. The slopes tend to follow the thermal fractions of the regions which range from 0.5 to 0.95. The thermal fraction of the RC emission alone can provide the expected FIR/RC correlation. The results are consistent with a common source for ultraviolet (UV) photons heating dust and Cosmic Ray electrons (CRe^?s) diffusing away from the star forming regions. Since the CRe^?s appear to escape the SMC so readily, the results here may not provide support for coupling between the local gas density and the magnetic field intensity.  相似文献   

Paleolithic hunting in a southern Moravian landscape: The case of Milovice IV,Czech Republic     

Ji&#x;í Svoboda  Zbigniew M. Boche&#x;nski  Vra ulíkov  Alena Dohnalov  Srka Hladilov  Martin Hloek  Ivan Hor ek  Martin Ivanov  Miroslav Krlík  Martin Novk  Alexander J.E. Pryor  Sandra Szelov  Rhiannon E. Stevens  Jaros&#x;aw Wilczy&#x;nski  Piotr Wojtal 《Geoarchaeology》2011,26(6):838-866

The Dolní Věstonice–Pavlov–Milovice area (Czech Republic) on the slopes of the Pavlov Hills provides an opportunity for correlating the geomorphology of the Dyje River valley with Gravettian settlement patterns. Although the sites vary in size and complexity, they create a regular chain of strategic locations at elevations between 200 m and 240 m asl. In 2009, a road collapsed into deserted cellars inside the village of Milovice and revealed a complex of archaeological layers deep within loess, at an elevation of only 175 m asl. This paper presents an analysis of this atypical archaeological site location and compares the results with the other sites. We argue that this location allowed direct contact with mammoth herds concentrated on the floodplain, while the aquatic environment offered possibilities for gathering plants and fishing. This site represents a new aspect of organized settlement, hunting strategies, and short‐distance human movements during the Gravettian within this area. © 2011 Wiley Periodicals, Inc.  相似文献   

Dioritic intrusions of the Slavkovský les (Kaiserwald), Western Bohemia: their origin and significance in late Variscan granitoid magmatism     

Pavla Kováříková  Wolfgang Siebel  Emil Jelínek  Miroslav Štemprok  Václav Kachlík  František V. Holub  Vratislav Blecha 《International Journal of Earth Sciences》2010,99(3):545-565

Mafic and intermediate intrusions occur in the Slavkovsky les as dykes, sills and minor tabular bodies emplaced in metamorphic rocks or enclosed in late Variscan granites near the SW contact of the Western Krušné hory/Erzgebirge granite pluton. They are similar in composition and textures to the redwitzites defined in NE Bavaria. Single zircon Pb-evaporation analyses constrain the age of a quartz monzodiorite at 323.4 ± 4.4 Ma and of a granodiorite at 326.1 ± 5.6 Ma. The P–T range of magma crystallization is estimated at ~1.4–2.2 kbar and ~730–870°C and it accords with a shallow intrusion level of late Variscan granites but provides lower crystallization temperatures compared to the Bavarian redwitzites. We explain the heterogeneous composition of dioritic intrusions in the Slavkovsky les by mixing between mafic and felsic magmas with a minor effect of fractional crystallization. Increased K, Ba, Rb, Sr and REE contents compared to tholeiitic basalts suggest that the parental mafic magma was probably produced by melting of a metasomatised mantle, the melts being close to lamprophyre or alkali basalt composition. Diorites and granodiorites originated from mixed magmas derived by addition of about 25–35 and 50 vol.%, respectively, of the acid end-member (granite) to lamprophyre or alkali-basalt magma. Our data stress an important role of mafic magmas in the origin of late Variscan granitoids in NW Bohemian Massif and emphasize the effect of mantle metasomatism on the origin of K-rich mafic igneous rocks.  相似文献