National Repository of Grey Literature 1,645 records found  1 - 10nextend  jump to record: Search took 0.31 seconds. 

Study of behavior of concrete and cement based composite materials exposed to high temperatures
Bodnárová, L. ; Horák, D. ; Válek, J. ; Hela, R. ; Sitek, Libor
The paper describes possibilities of observation of behaviour of concrete and cement based composite material exposed to high temperatures. Nowadays, for large-scale tests of behaviour of concrete exposed to high temperatures, testing devices of certified fire testing stations in the Czech Republic and surrounding states are used. These tests are quite expensive. For experimental verification of smaller test specimens, a testing device was built at the Technical University in Brno, where tests of thermal loading of concrete tests specimens of various sizes can be carried out (dimensions up to 800 x 800 x 800 mm or slabs up to 1100 mm of length). The testing device opens new ways of observation of behaviour of concrete and cement based composite materials exposed to high temperatures as well as preparation of specimens for observation of interaction of water jet and concrete degraded by action of high temperatures.
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Universal diagnostic device for accumulators
Němec, Filip ; Lattenberg, Ivo (referee) ; Balík, Miroslav (advisor)
Firstly, this bachelor thesis handles the issues concerning NiCD and NiMh batteries and methods used when charging and discharging. Next segment of the document deals with designing and the actual realization of a device, which can work with these batteries and perform variable tasks,such as charging and discharging battery with adjustable current value, measuring temperature of the battery. Sending data via the serial port,it also implements charging and discharging curve. Device can be operated intuitively using buttons and display. The Device is realized via microcontroller ATMEL.

Processes of Nanoparticle Formation in Low Temperature Plasma
Brožek, V. ; Mastný, L. ; Moravec, Pavel ; Neufuss, Karel ; Ondráček, Jakub ; Ždímal, Vladimír
This work describes the synthesis of nanoparticles during interaction of several different metals (Ag) or their respective oxides (TiO2, Cr2O3) with oxygen-hydrogen plasma having temperatures above 25000 K. Resulting nanoparticles and/or their aggregates in the size range of 25-300 nm were deposited on metallic targets and/or trapped in the water filters and separated using ultra-centrifugal apparatus. The aerosol spectrometer SMPS 3936 (scanning mobility particle sizer) was used to study the particle size distribution of generated nanoparticles in the size range 14 – 700 nm. In order to extend the measured particle size range towards larger sizes, the APS 3321 spectrometer (aerodynamic particle sizer) with the size range 500-20000 nm was used simultaneously. Both spectrometers were set-up to sample with three minute time resolution. Process conditions and production of inorganic nanoparticles of defined composition are discussed in this work.
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Experimental Investigation of Flow on Airfoils with High Lift Devices and Spoilers
Součková, N. ; Popelka, Lukáš ; Matějka, M.
The results of flow visualization by means of PIV method on airfoils with spoilers and high-lift flap have been given.

Modern methods of wet cleaning flue-gas
Kubíček, Jan ; Grolig, Ondřej (referee) ; Dvořák, Radek (advisor)
The main theme of this master’s thesis is to acquaint with flue gas cleaning problems. Also modernization of experimental device called “O-element”, installed in laboratory at Institute of process and environmental engineering, is involved in this master’s thesis. “Oelement is used for cleaning acid elements from flue gas. Further there are results of experimental measuring on this device, and their estimation.

Computer control of photoluminescence spectrometer used for characterization of semiconductors
Kostka, František ; Zavadil, Jiří ; Krechler, Jindřich ; Dvořák, Martin ; Svatuška, Michal ; Gladkov, Petar
Basic electronics and programming that enables a computer control of experimental set-up for low-temperature photoluminescence /PL/ spectroscopy and PL topography is briefly described together with the physical principles behind photoluminescence spectroscopy as a characterization technique.

Thickness dependence of transport properties of Bi.sub.2./sub.Te.sub.3./sub. layers
Zeipl, Radek ; Lošťák, P. ; Pavelka, Martin ; Žďánský, Karel ; Jelínek, Miroslav ; Walachová, Jarmila
The transport properties of layers, prepared by laser ablation, as Hall mobility and conductivity on their thickness at room temperature are presented. This thermoelectric materials is potential candidate for many applications as for thermoelectric devices for power generation, cooling and sensors.

Thickness dependence of transport properties of Bi.sub.2./sub.Te.sub.3./sub. layers
Zeipl, Radek ; Lošťák, P. ; Pavelka, Martin ; Žďánský, Karel ; Jelínek, Miroslav ; Walachová, Jarmila
The transport properties of layers, prepared by laser ablation, as Hall mobility and conductivity on their thickness at room temperature are presented. This thermoelectric materials is potential candidate for many applications as for thermoelectric devices for power generation, cooling and sensors.

Comparison of quantitative LIBS analysis of steel standards utilizing single-pulse and double-pulse LIBS
Pořízka, Pavel ; Hrdlička, Aleš (referee) ; Kaiser, Jozef (advisor)
In this diploma thesis the differences between single pulse and double pulse laser induced breakdown spectroscopy (LIBS) methods are discussed. The time evolution of laser induced plasma (LIP) parameters, such electron density, plasma temperature, density of ions and atoms is shown. Selected methods for evaluation of plasma parameters (Boltzmann equation, Saha-Boltzmann equation etc.) are also stated. The theoretical bases of local thermodynamic equilibrium (LTE), which is necessary condition for using of previously stated methods for computation of plasma parameters, are discussed. Diploma thesis also contains the description of each component of our LIBS experimental set up and the way of their optimization. Presented theoretical advantages of DP LIBS method are demonstrated on results of experimental measurements of steel standards.

Design of a space heating system with heat pump in family house
Valešová, Jaroslava ; Charvát, Pavel (referee) ; Katolický, Jaroslav (advisor)
This master`s thesis deals with low-temperature heating that employs a heat pump. The introduction gives reasons for utilization of the renewable heat sources for heating. The next part focuses on a practical application of renewables on the heating of a family house. It covers a detailed description of the building and the designed heating system which includes: the calculation of thermal losses, design of the low-temperature boiler, heat pump, safety devices, heating elements, sizing and control of the system. The last part is devoted to the assessment of the system performance.