Rayleigh waves in the period range 0.2 - 3.0 s from eight quarry blasts are analyzed to obtain S-wave velocity model beneath the Příbram seven-station array in the Czech Republic. Locations and origin times of blasts are estimated using P- and S-wave onsets and then verified at the quarry in the vicinity of the location. This blind test confirms a sufficient precision of the location procedure for identification of quarries. Epicentral distances are in the range from 16 to 52 km. Group velocity dispersion curves of Rayleigh waves are determined by the frequency-time analysis. An average group velocity beneath the array for each period is computed with the help of mean travel-time curve for all blasts and stations. The resultant group velocity dispersion curve is inverted to obtain a 1-D S-wave velocity model using the Isometric method. The results are compared with known geological structure in the area of interest., Renata Gaždová, Petr Kolínský, Jiří Málek and Jan Vilhelm., and Obsahuje bibliografii
Vermiculite (V) from Brazil with aqueous solutions AgNO3 and/or Cu(NO3)2 was used for preparation of nanocomposites V/Ag, V/Cu, V/AgCu and V/CuAg using two procedures and their effect on bacteria was compared. Structural changes were evaluated using X-ray diffraction (XRD) analysis, Infrared spectroscopy (IRS) and Scanning electron microscopy (SEM). Elemental chemical composition was determined using X-ray fluorescence (XRF) analysis and the solutions were analyzed by Atomic emission spectroscopy with inductively coupled plasma (AES-ICP). Antibacterial properties of Ag- and Cu-vermiculites and combined Ag/Cu-vermiculites were tested on two bacteria groups: (1) Gram-positive, G+, (Staphylococcus aureus and Enterococcus faecalis) and (2) Gram-negative, G-, (Pseudomonas aeruginosa and Klebsiella pneumoniae). The samples under antibacterial testing showed different effective times and minimum inhibitory concentration (MIC) values. The Gram-negative bacteria showed higher sensitivity to the prepared samples than Gram-positive bacteria. The combined Cu/Ag vermiculites stopped the bacterial growth at lower MIC value., Marianna Hundáková, Marta Valášková, Vladimír Tomášek, Erich Pazdziora and Kateřina Matějová., and Obsahuje bibliografii
Oxidation kinetics of celulose, lignin, brown coal, and their mixtures were investigated. Using non-linear regression method kinetic parameters from thermogravimetric curves were calculated for oxidation of volatile matter and fixed carbon (char). The presence of the cellulose in the mixture affects the rate constant of lignin and brown coal oxidation which was determined by means of Arrhenius plots., Petr Šušák, Silvie Vallová and Juraj Leško., and Obsahuje bibliografii
Series of repeated epoch-wise GPS campaigns performed in Central European region are used for estimation of site velocities. The main features of campaign processing and combination of network solutions are outlined. The velocities obtained from epoch observations within the Central Europe Regional Geodynamic Project covering the 11-year time span are compared at some sites with velocities derived from permenent GPS observations., Ján Hefty and Ľubomíra Gerhátová., and Obsahuje bibliografii
Stability conditions in a wider surrounding of the rock castle Drábské Světničky (Drábské Rooms) near the town of Mnichovo Hradiště were investigated. The area which has been intensively disturbed by large old as well as present slope movements is located in the north-western part of Příhrazy Platform. Solid, thick bedded sandstones, well resistant to weathering, are lying on claystones apt to plastic deformations. Marginal sandstone blocks separate, move down on the slope and sink into the plastic bedrock. As a result, block fields with many crevasses develop. In rock walls that separate individual blocks, rockfalls originate and central, as well as lower parts of the slopes develop large landslides. A zone comprising up to 400 m wide rim of the high and exposed platform has been subject to a process of loosening. A local group of tower-like sandstone blocks was used in the 15th century to build a small rock castle called Drábské Světničky. An extensive landslide that destroyed a substantial part of the village of Dneboh in June 1926, reached in its separating zone up to the toe of marginal rock towers belonging to the complex of Drábské Sv ě tni č ky with the result of local movement activation. Marginal zones of the flat land behind display fresh linear, as well as oval depressions and sinks. Fissure and pseudocarst caves develop. Present activity of the movements has been evidenced by dilatometric measurements on two selected rock objects where movement rates reached 1 to 2 mm per year in average., Jan Rybář, Josef Stemberk and Filip Hartvich., and Obsahuje bibliografické odkazy
The character of modern pedogenesis in the territory of the Brdská and Křivoklátská vrchovina Highlands was studied on silicate rocks such as Paleozoic granite and Proterozoic mudstone and greywacke. The parent materials were evaluated on the basis of petrography, X-ray diffractometry of powder samples of rock forming and heavy minerals. The soils were described as for their macromorphological characterics and the results of a variety of analyses of organic and anorganic components. Pedogenesis proceeded in acid conditions. The values of base saturation are mostly below 50 % for the Ah horizons. The intensity of soil development on individual parent material decreases in the order: mudstone (Ah-AhBw-Bw-C)granite (Oi-Oe-Oa-Ah-Bw-C)greywacke 1 (Oi-Oe-Oa-Ah-AhC-C)greywacke 2 (Oi-Oe-Oa-Ah-C). The process of humification was documented at all study sites. Evidence of pedogenetic alteration is present in soils developed on granite and mudstone. High amounts of chlorite and elevated contents of illite are characteristic for Cambic Leptosols (Dystric, Skeletic) on mudstone. Weddellite and whewellite were found in relatively large amounts in O horizons of soils except for the Červený kríž site. The predominant from of calcium oxalate minerals at these sites is whewellite. Weddellite occurs in small amount, which is probably due to its lower stability., Anna Žigová, Martin Šťastný, Petr Mikysek., and Obsahuje bibliografické odkazy
The bicentennial varia tions of the Earth rotation consist of several oscill ations with most known periods 178.7a (Jose cycle), 210a and 230a (de Vries cycle); they are driven by the solar cycles which affect climatic variations, followed by global environmental changes. These periods are close to the higher harmonics of millennial Hallstatt cycle (2300a), so the proper separation between the indi vidual bicentennial cycles needs time series longer than 2300a. The bicentennial variations of the Universal Time (UT1) in relation to the Terrestrial Time (TT) are investigated using reconstructed time series of the Total Solar Irradiance (TSI) for the last 9300a. A linear regression model of TSI influe nce on the UT1 and the Mean Sea Level (MSL) bicentennial variations are created. The parameters and time series of the bicentennial UT1-TT oscillations for the last 9300a are determined., Cyril Ron, Yavor Chapanov and Jan Vondrák., and Obsahuje bibliografické odkazy
A grant project for the period 2003-2005, supported by the Grant Agency of the Czech Republic, was set up to determine properties of seismic waves and the structure of the uppermost part of the Earth´s crust in the territory of northern Moravia and Silesia. Quarry blasts and mining induced seismic events served as seismic sources. Permanent, temporary and portable seismic stations were used for the monitoring of these seismic events. During the experiments local microearthquakes were also detected and localized. For the complex evaluation of seismic wave features, data of the CELEBRATION 2000 and SUDETES 2003 refraction experiments were incorporated, as well. The velocity-depth dependence of body waves was searched by joint inversions of travel times of Pg/Sg phases. A special feature of the wave trains, generated by quarry blasts, was a pronounced dispersive character of short-period Rayleigh surface waves. These waves enabled us to establish their dispersion curves, on the basis of which the structure of superficial layers was determined down to a depth of several hundreds of meters., Karel Holub, Jaromír Knejzlík, Bohuslav Růžek, Jana Rušajová and Oldřich Novotný., and Obsahuje bibliografii
In this work, the set of procedures to prepare the GPS vector solutions time series (VSTSGPS) to spectrum analyses is presented. This preparation is shared on two stages. In the first stage, the breaks filling was processed. This stage was achieved in two steps. Firstly, the breaks filling was computed on the base of time series of other vectors. Secondly, the breaks filling was computed using the interpolation or extrapolation methods. The next stage of VSTSGPS preparing implicated the time series smoothing to remove the impulse noises. After breaks filling and smoothing the VSTSGPS were tested for admission to further analyses., Daniel Jasiurkowski., and Obsahuje bibliografické odkazy
Among the programmes aimed at developing a standard model for properties and state of the Earth’s crystalline crust, those dealing with drilling the Kola (SG-3), Ural (SG-4) and German (KTB) superdeep boreholes yielded the most interesting results. No marked depth dependence of rock volume density and seismic wave velocities was observed in the sections of SG-3 and SG-4. A new result of the investigations is the discovery of strongly anisotropic rocks in the SG-3, SG-4 and KTB sections. In the massifs of the Kola and German superdeep boreholes such rocks constitute the majority of the drilled sections. The presence of the velocity anisotropy as well as the complex structure of the rocks composing crystalline metamorphosed sequences greatly hamper the interpretation of the results obtained from the seismic survey conducted at the surface., Felix F. Gobratsevich., and Obsahuje bibliografii