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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Výroba plynových ventilů na automatické lince / Production of gas valves on the automatic line

Pešl, Milan January 2011 (has links)
This thesis deals with the evaluation of manufacturing gas valves on the automatic line and the design of CCTV systems to detect errors at assembly in Honeywell Czech Republic Ltd. The aim of this thesis is mutual comparison of the respective proposed options of the camera system, their optimal selection, and the evaluation of detected errors of the line by using Pareto Charts. An integral part of this work is a brief description of the automatic line for gas valves and the history of Honeywell Company.
12

Nové fluorosenzory na bázi derivátů naftalimidu / Novel fluorosensors based on naphthalimide derivatives

Garbárová, Veronika January 2019 (has links)
The aim of the diploma thesis was to prepare and characterize fluorescence sensor systems based on fluorophores and supramolecular components - cyclodextrins - attached to solid supports. In this work, functionalized 75 µm glass beads and two types of Nafion membranes were used as negatively charged solid surfaces. Derivatives of naphthalimide with a positively charged part allowing the attachment to surfaces were synthesized. The positively charged naphthalimide derivative was then attached on negatively charged surfaces via electrostatic interactions and the binding to the solid supports was examined using UV-VIS spectroscopy. Alternatively, the positively charged β-cyclodextrin derivative was also attached to the surface in an equimolar ratio with PNI-HEMPDA. The focus of the work were measurements of fluorescence sensor responses in the gas and liquid phase to linear alcohols - methanol to n-hexanol - for all sensor systems. For the studied sensor systems, the selected sensor parameters were determined - sensitivity, the limit of detection, linear dynamic range and a sensor response time constant. A practical application of the novel sensor system for the detection of ethanol in gasoline was examined. Fluorescence sensor response measurements of the prepared systems based on naphthalimide and...
13

Modifikace nanočástic za letu pomocí chemicky aktivního plazmatu / In-flight modification of nanoparticles by chemically active plasma

Libenská, Hana January 2019 (has links)
Title: In-flight modification of nanoparticles by chemically active plasma Author: Hana Libenská Department: Department of Macromolecular Physics Supervisor: Mgr. Jan Hanuš Ph.D., Department of Macromolecular Physics Abstract: This diploma thesis is focused on a fabrication of the iron nanoparticles using the gas aggregation source with a planar magnetron and their in flight modification by chemically active plasma. The modification of the nanoparticles is based on a radiofrequency glow discharge, that takes place right after the nanoparticles flew out of the gas aggregation source. Nanoparticles are prepared in an argon atmosphere in which a small amount of the n-hexane has been admixed. This n-hexane impurity caused an increase in a deposition rate and higher time stability. The modification takes place in a glow discharge containing a pure argon, or in the mixtures of argon with n-hexane, ethylendiamine, hydrogen or nitrogen. Prepared nanoparticles were characterized using the X-ray photoelectron spectroscopy, scanning and transmission electron microscopy, X-ray diffraction and other techniques. The main aim of this work was to study the influence of the additional discharge on the iron nanoparticles. The chemical composition of the nanoparticles was measured immediatelly after their deposition without...
14

Charakterizace vysoce porézních Pd-modifikovaných SnO2 naprášovaných tenkých vrstev pro detekci H2 / Characterization of highly porous Pd-modified SnO2 sputtered thin films for H2 detection

Chundak, Mykhailo January 2015 (has links)
Title: Characterization of highly porous Pd-modified SnO2 sputtered thin films for H2 detection Autor: Mgr. Mykhailo Chundak Department/Institute: Department of Surface and Plasma Science Supervisor of the doctoral thesis: RNDr. Kateřina Veltruská, CSc., Department of Surface and Plasma Science Abstract: This doctoral thesis contains the study of tin dioxide and Pd-doped tin dioxide samples deposited by magnetron sputtering utilizing glancing angle deposition (GLAD). Influence of the deposition parameters on the change of morphology, crystalline structure and chemical state was studied. The samples were characterized by a variety of techniques, such as: X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), synchrotron radiation photoelectron spectroscopy (SRPES), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). Prepared samples showed high porosity which could be controlled by deposition parameters (angle of the deposition, gas pressure and power of magnetron discharge). Highly porous SnO2 GLAD samples and Pd modified SnO2 GLAD samples were deposited on the substrates at room temperature and 300 řC. These samples were found to be polycrystalline with certain fraction of amorphous contribution, given by preparation conditions. The size of the...
15

Optimalizace intenzivního chovu larev candáta obecného (Sander lucioperca L.)

MORAVA, Jakub January 2018 (has links)
The aim of this master thesis was test, comapre and observe the best density of rotifers (Brachionus plicatilis) for growth and survival of zander (Sander lucioperca) larvae stage in the recirculation aquatic systém (RAS). The secondary experiment tests initial feeding of zander by dint of rotifers and consequently by mix of rotifers and artemia. Main experiment observe effect of different density of rotifers on survive and growth of zander. Other observe parameters such as Fulton´s coeficient, total lenght of fish, weight of fish, etc. Fish was divided into 4 groups with different density of feeding and the control group without feeding. Rotifers has been used in density of 2, 6, 10 and 20 pieces per larva. The best growth in "D" group has been compensate by lower surviving. On the other hand the best ratio of survive has been observe in "C" group, which showed lower growth. The optimal rate of growth and survive has been declared in "B" group, which were feed with dose of 6 pieces rotifers for larva. In the second experiment were observe body changes of zander after initial feeding by rotifers folowed with feeding mix of rotifers and artemia. There were observe successful fulfillment of gas bladder and deformation of fish body and spinal after 40 days of keeping larvae in RAS. In the end of experiment there were also observe defirmations body - for example missing lower jaw, upper jaw or both of them. Spinal deformities occured in the form of scoliosis, lordosis, kyphosis and zig zag distortion. The experiment has shown that unsuccessfully filled gas bladder is closely related to the formation of deformitiy in the zander. Another negative factor that affects the filling of the gas bladder is grease on the surface of the water level, so I recommend installing the grease trap in the fill phase of the gas bladder.
16

Historie dolování uranového ložiska Příbram / History of mining uranium deposit in Příbram

SASKOVÁ, Klára January 2010 (has links)
The region I´ve chosen for my diploma thesis is situated on the border of Poberounská and Czech-Moravian system of geomorphological unit Bohemian Massif. It used to be one of the richest uranium mining district of Příbram region, and it is characterized by geological structure of central-Bohemian plutonium within the geological complex Bohemian Massif. On the contiguity of it there is found vast hydrothermal uranium deposit. This deposit is divided into 9 panels ? Třebsko, Kamenná, Lešetice, Brod, Jeruzalém, Háje, Svatá Hora, Bytíz, Skalka and Obořiště, which belong to the Příbram district. The town Příbram is famous for its long-standing mining tradition not only of polymetalic but above all of uranium ores. This tradition achieved the great success of world standards in the second half of the 20th century. There was revealed a lot of hydrothermal dikes containing requested uranite (black blende, nasturan) after the Second World War. This raw material was heading to Soviet Union. Uranium mining works initiated its epoch in 1949 and regular mining activities finished by the closing of the last shaft in 1991. In all the period of time there was mined 50200, 8 tones of uranium ore. Uranium deposit in Příbram can also take pride in the deepest shaft No. 16 with the depth of 1838, 4 m which is the shaft No. 16. In connection with the mining there was formed the life of local people and also the life of people from all Czechoslovakia who were setting off to seek a living there. Today all the shafts are closed and deluged in a natural way. In certain area of the deposit has been built cavern gas reservoir. No other mining will be possible in the future. The state enterprise Diamo realizes revitalization works on former mining panels and monitors the value of surrounding environment.
17

Vytápění objektu zdroji na různé druhy paliv / Heating of the Object with Different Fuels

Ladomérská, Jana January 2015 (has links)
In my final thesis I am processing a proposal for heating and preparing hot water for a restaurant with accommodation. This is a three-storey brick house. It is situated on the territory of the Ústí region. The aim of my work is to propose and to assess the appropriate heat source for this object. In the object I chose heating radiators. The proposal is processed in two variants. In the first variant, I suggest a cascade of condensing boilers using as a source of heat. In the second variant, I suggest a cascade of electrical boilers. Hot water will be prepared in reservoir of warm water. The source of hot water will be the same as the source for heating.
18

Srovnání možných způsobů zásobování rodinného domu energií / Comparison of energy sources for energy supply of residential

Špatenka, Jindřich January 2014 (has links)
This diploma thesis deals with comparison of possible ways to supply the specific house by thermal energy. In the first part is a brief introduction of the building and determination of heat consumption. Following chapters are devoted to description and sorting of gas boilers, heat pumps, biomass boilers and solar collectors, inclusive the choice of specific source of heat. In the following part is stated economic evaluation of selected heat sources. Final part of the thesis is focused on design of additional exchanger instead of gas boiler.
19

Spojení kondenzačního kotle se solárními kolektory pro zásobování RD tepelnou energií / Condensing boiler with solar collectors for thermal energy supply of residences

Zeman, Radek January 2016 (has links)
This diploma thesis deals with practical design of heat supply of real house in Libhošť, Nový Jičín. Main strategy of heat supply is gas condensation boiler, that replaces current gas boiler, with solar collector. From known house heat loss we determine temperatures of heating water and power of boiler, that heats the house and hot water. System with solar collector is designed to heat hot water in the house. All necessary equations are calculated both for long term measured meteorological data and for data in year 2015. Heat gains and payback periods of investment in solar system are determined from them. Payback periods are calculated given to price of heat that gas boiler produces. Equations and payback period evaluation are made for systems with one to four solar collectors. There is recommendation at the end of thesis, whether the solar system is advantageous, or not.
20

Vytápění bytového domu / Heating of flat house

Matoulková, Jana January 2017 (has links)
The point of the thesis was to design a heating system for new residential building, situated in Nový Lískovec, Brno. As a source of heat has been designed condensing boiler fueled by gas that meets the need for heating of heating system and hot water. All of the equipment will be located in a utility room on the ground floor. In the apartment have been designed decorative panel radiators.

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