The article presents results of the verification calculation of the method for the calculation of natural frequencies and mode shapes of a linear undamped rotationally periodic systems considering the possibility of the elimination of degrees of freedom. As the test example a thin circular plate was chosen. The method can be applied e.g. for the calculation of the natural vibration characteristics of the steam turbine bladed disks. and Obsahuje seznam literatury
At the modernization of the ŠKODA 22 Tr low-floor articulated trolleybus a different type of an articulated joint and a different type of driving axles were used in its construction besides other changes. During test drives with the modernized trolleybus, which were focused on the driving stability of the vehicle, a large roll of the rear section appeared. A suitable structural solution for reducing the rear section roll angle of the modernized trolleybus was the using of a rear section stabilizer bar. The stabilizer effect on dynamic properties of the vehicle and a suitable bar diameter were determined on the basis of the results of the computer simulations with the trolleybus multibody models. The text drives focused on the vehicle driving stability were performed again with the loaded real trolleybus, in the structure of which the designed rear section stabilizer bar was applied. On the basis of computer simulations of the test drives with the trolleybus multibody models the correctness of the experimantal-simulation approach used for the stabilizer bar structural design was verified. and Obsahuje seznam literatury
Knihovna Akademie věd ČR Praha CZ TF 347 adl. 16 def., Královská kanonie premonstrátů na Strahově - Strahovská knihovna Praha CZ BP VI 51/36, Královská kanonie premonstrátů na Strahově - Strahovská knihovna Praha CZ BU II 110/11, Národní knihovna ČR Praha CZ 46 C 187 adl. 9, Klášter Rytířského řádu křižovníků s červenou hvězdou - knihovna Praha CZ XV H 17 adl. 8, Klášter Rytířského řádu křižovníků s červenou hvězdou - knihovna Praha CZ XV H 17 adl. 9, and BCBT03716
Vermiculite in its macroscopic form occurs in the Archaean supracrustal rocks exposed towards east of Sargur supracrustal complex in Karnataka state. The present study forms the first detailed work on the occurrence of vermiculite associated with the ultramafic rocks in the Agasthyapura, which lies in the long. 76° 50’ 658” and lat. 12° 15’ 976”. Petrography, X-ray diffraction, FTIR, DTA&TGA, SEM, fluid inclusion and electron probe analyses are presented in this contribution study. The probable origin of vermiculite from biotite through hydrobiotite is discussed., Kikkeri N. Prakash Narasimha, Honnaiah Ramalingaiah, Karel Melka, K. Krishnaveni, Pinnelli S. R. Prasad, Chikkamadaiah Krishnaiah, Katihalli S. Jayappa and Atni V. Ganesha., and Obsahuje bibliografické odkazy
In presented work natural expanded vermiculite was used as a starting material for synthesis of Fe-doped catalysts. Material was modified with increasing amount of Fe by ion-exchange and precipitation of iron oxide. Composite materials were characterized with respect to their structure (X-ray diffraction, Infrared spectra using Diffuse Reflectance), agglomeration state of Fe (Ultraviolet-Visible spectra using Diffuse Reflectance) and chemical composition. Activity in H2O2 decomposition as well as in phenol oxidation was studied in liquid phase at atmospheric pressure and temperature up to 70 °C. It was shown that doping with Fe increases catalytic activity. However, excess of iron resulted in formation of undesired side-products., Agnieszka Węgrzyn, Lucjan Chmielarz, Paweł Zjeżdżalka, Magdalena Jabłońska, Andrzej Kowalczyk, Agata Żelazny, Manuel Vázquez Sulleiro and Marek Michalik., and Obsahuje bibliografii