On the techniques of analysing the multi-component magnetization of rocks using the Rocoma magnetometer     

Miroslav Krs  Richard Chvojka  Reviewer V. Bucha 《Studia Geophysica et Geodaetica》1987,31(2):176-196

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Possibilities of the utilization of micropetrographic parameters in the scientific classification of bituminous coals     

Miroslav Košina 《International Journal of Coal Geology》1984,4(3):263-280

Proposals for new scientific classifications of bituminous coals are based on micropetrographic parameters, i.e. vitrinite reflectance as a criterion of the coalification and maceral composition, presupposed to express the connection between the genetic peculiarities and physical, chemical, and technological properties of the coal mass. In the case of coals with high inertinite contents, however, the utilizability of these parameters meets with difficulties resulting from the subjectivity of determining the different transitional material and from insufficient knowledge of inertinite behaviour at higher temperatures. In the case of the maceral-variable bituminous coals produced in the Ostrava-Karviná Coal Basin, these insufficiencies are not important since it is especially the expression of the variability of the properties of isometamorphic vitrinites, which has decisive effects up-on the course of the thermo-chemical transformations, that is of principal importance to the scientific classification of these coals.In the first approximation, the properties of isometamorphic vitrinites may be expressed by the parameter (H/O)_at, closely connected with fluidity. While the micropetrographic parameters reflect in particular the peculiarities in the chemical structure of the aromatic parts of coal macromolecules, the parameter (H/O)_at expresses the properties of the non-aromatic structures of vitrinite, significantly affecting the course of its thermal degradation. The experimental results show that the value of the parameter (H/O)_at, fluidity and the course of degassing the coal of a lower coalification are independent of the maceral composition and vitrinite reflectance; also that the caking and coking properties of low-rank coals are especially dependent on the parameter (H/O)_at and partially on the micropetrographic parameters. All these facts should be taken into consideration in preparing new scientific classifications of bituminous coals.  相似文献   

Palaeointensity of the geomagnetic field during upper cainozoic derived from palaeo-slags and porcellanites in north Bohemia     

Marta Krsová  Miroslav Krs  Petr Pruner  Richard Chvojka  Reviewer V. Kropáček 《Studia Geophysica et Geodaetica》1989,33(4):338-361

Summary Porcellanites and palaeo-slags from North Bohemia are natural materials which can be used to derive the palaeomagnetic directions and palaeointensity of the geomagnetic field active at the time of caustic alteration. The origin of these rocks, called erdbrands, was due to the caustic alteration of predominantly pelitic sediments as a result of underground fires conditioned by spontaneous ignition of coal seams. The caustic alteration occurred during the Upper Pliocene to the Quaternary. Three procedure based on the methods by Thellier and Nagata are presented in the paper. The newly developed apparatus MAVACS (Magnetic Vacuum Control System) was used for the thermal demagnetization of samples. A procedure based on multi-component analysis was also proposed and tested. Besides some methodic results, it was found that the geomagnetic field intensity varied during the respective period within the limits of 48%±4% to 154%±32% of the present geomagnetic field intensity.

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Zur Frage Der Elektrotechnischen Klassifikation Des Klimas     

Miroslav Rychtera  Jarmila Reinhartová 《Studia Geophysica et Geodaetica》1960,4(4):389-403

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Size-resolved characterisation of organic compounds in atmospheric aerosols collected at Welgegund,South Africa     

Wanda Booyens  Pieter G. Van Zyl  Johan P. Beukes  Jose Ruiz-Jimenez  Matias Kopperi  Marja-Liisa Riekkola  Miroslav Josipovic  Andrew D. Venter  Kerneels Jaars  Lauri Laakso  Ville Vakkari  Markku Kulmala  Jacobus J. Pienaar 《Journal of Atmospheric Chemistry》2015,72(1):43-64

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Seismic fragility assessment of low-rise stone masonry buildings     

Ahmad Abo-El-Ezz  Marie-José Nollet  Miroslav Nastev 《地震工程与工程振动(英文版)》2013,12(1):87-97

Many historic buildings in old urban centers in Eastern Canada are made of stone masonry reputed to be highly vulnerable to seismic loads.Seismic risk assessment of stone masonry buildings is therefore the first step in the risk mitigation process to provide adequate planning for retrofit and preservation of historical urban centers.This paper focuses on development of analytical displacement-based fragility curves reflecting the characteristics of existing stone masonry buildings in Eastern Canada.The old historic center of Quebec City has been selected as a typical study area.The standard fragility analysis combines the inelastic spectral displacement,a structure-dependent earthquake intensity measure,and the building damage state correlated to the induced building displacement.The proposed procedure consists of a three-step development process:(1) mechanics-based capacity model,(2) displacement-based damage model and(3) seismic demand model.The damage estimation for a uniform hazard scenario of 2% in 50 years probability of exceedance indicates that slight to moderate damage is the most probable damage experienced by these stone masonry buildings.Comparison is also made with fragility curves implicit in the seismic risk assessment tools Hazus and ELER.Hazus shows the highest probability of the occurrence of no to slight damage,whereas the highest probability of extensive and complete damage is predicted with ELER.This comparison shows the importance of the development of fragility curves specific to the generic construction characteristics in the study area and emphasizes the need for critical use of regional risk assessment tools and generated results.  相似文献   

Influence of climatic factors on the low yields of spring barley and winter wheat in Southern Moravia (Czech Republic) during the 1961–2007 period     

Petr Kolář  Miroslav Trnka  Rudolf Brázdil  Petr Hlavinka 《Theoretical and Applied Climatology》2014,117(3-4):707-721

The paper aims to study the variability of spring barley and winter wheat yields, the most important crops in the Czech Republic, with respect to the variability of weather and climatic factors. Yields of both crops have been studied for 13 districts in Southern Moravia for the 1961–2007 period. From detrended series of spring barley and winter wheat yields, years with very low (lower than the mean minus a 2.5-multiple of the standard deviation) and extremely low (interval given by the mean minus a 1.5- and 2.5-multiple of the standard deviation) yields were selected. Years in which at least one of the districts had extremely low/very low yields were further analyzed. From 10 such years selected separately for spring barley and winter wheat, six of them agreed for both crops. Extreme years were studied using NUTS4-level yield data with respect to temperature, precipitation, the self-calibrated Palmer Drought Severity Index (scPDSI), snow cover, frost patterns, and the onset and duration of select phenophases. Extremely/very low barley yields in 1993, 2000, and 2007 were related to high April–June (AMJ) temperatures, low AMJ precipitation totals, and negative AMJ scPDSI (indicating drought) with an earlier onset of flowering and full ripeness and shorter intervals from tillering to flowering and from flowering to full ripeness compared to the entire 1961–2007 mean. As for extremely/very low winter wheat yields, in addition to the previously mentioned factors, winter patterns also played an important role, particularly the occurrence of severe frosts with a coinciding lack of snow cover and a long-lasting snow cover (in highlands), indicating that low yields are the result of not only one unfavorable factor but a combination of several of them.  相似文献   

Urban field classification by “local climate zones” in a medium-sized Central European city: the case of Olomouc (Czech Republic)     

Michal Lehnert  Jan Geletič  Jan Husák  Miroslav Vysoudil 《Theoretical and Applied Climatology》2015,122(3-4):531-541

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The role of primordial kicks on black hole merger rates     

Miroslav Micic  Tom Abel  Steinn Sigurdsson 《Monthly notices of the Royal Astronomical Society》2006,372(4):1540-1548

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Methods in computational physics,vol. 7, astrophysics     

Miroslav Plavec 《Astrophysics and Space Science》1968,1(4):519-520

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