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Implementation of Pasive Optical Network
Klaška, Patrik ; Jordán, Vilém (referee) ; Ondrák, Viktor (advisor)
This bachelor´s thesis is focused on making a complete proposal optical access network for emerging buildings, and later connect other sites in the village Hrušky near the town of Slavkov u Brna. The main goal is the implementation of FTTx networks, describe the problems associated with them with regard to current and future trends in the construction and management of these networks.
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Biological activity of plant metabolites. XVI. Alkaloids of Papaver somniferum L. and their activity to acetylcholinesterase
Filáková, Ivana ; Siatka, Tomáš (referee) ; Opletal, Lubomír (advisor)
Filáková, I.: Biological activity of plant metabolites XIV. Alkaloids of Papaver somniferum L. and their activity to acetylcholinesterase. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2010, 63 p. Within the screening of plants containing alkaloids potentially inhibiting human erythrocytic AChE and human butyrylcholinesterase was studied poppy (Papaver somniferum L) It was used 30 kg of poppy straw, basic extract was prepared by extraction of 95% alcohol. From this primary extract were prepared extracts with individual types of alkaloids by sequent procedue. In this diploma thesis only one extract was processed (extract type A-ether, pH 9 - 10). Alkaloids from this extract were separated into bases, where its chlorides are soluble and insoluble in chloroform. From each of above mentioned fractions phenolic and non-phenolic alkaloids has been obtained. In this work were separated alkaloids from extact AC1 (chlorides soluble in chloroform, non-phenolic. From this mixture was isolated thebaine by the using of column chromatogramy on alumina and preparative TLC on silica. This compound has been preliminary identified according to data of MS, melting point, optical rotary and by comparison with standard...
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Study of starvation in a grease-lubricated elastohydrodynamic contact
Kuňák, Jiří ; Hartl, Martin (referee) ; Svoboda, Petr (advisor)
This diploma thesis is an experimental study of grease lubrication in a starved elastohydrodynamic lubricated (EHL) contact. Lubricating film thickness is measured with tribological experimental device ball-on-disc using optical interferometry and high speed camera. The experiment is aimed at a comparison of results acquired by ball-on-disc device and full scale axial bearing. In addition, this paper also investigates the influence of number of the rolling elements (overrolling time) on the resulting film thickness.
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Risk and safety analysis by optical test unit
Mank, Slavomír ; Drlík, Michal (referee) ; Blecha, Petr (advisor)
This thesis discusses of safety of machinery from production of our company. It is an optical measuring station to check spin valve stroke of inlet valve of the high pressure fuel pump. It also deals with the analysis of the legislative situation in this field. After initially acquaintance, the block diagram creating and definition of the limits, was conducted risk analysis of machinery.
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Design and Realization of the Second Generation Imaging Reflectometer and its Application in Optical Analysis of Thin Films
Vodák, Jiří ; Držík,, Milan (referee) ; Klapetek, Petr (referee) ; Ohlídal, Miloslav (advisor)
The work deals with a technique of imaging spectroscopic reflectometry developed at The Institute of Physical Engineering, Brno University of Technology. The technique is well suited for characterization of samples non–uniform along their surfaces. The technique is primarily used for optical characterization of thin films. First part of the work is focused on basic physical principles of the technique and on ways in which measurement data are obtained. It contains a basic description of evaluating methods and a basic concept of an imaging spectroscopic reflectometer with a description of main parts of such a device. The main part of the work is focused on a description of two devices which were built at The Institute of Physical Engineering together with a description of some of upgrades which were implemented to these devices during their development. A description of measurements done with the two devices is also included. Last part of the work is then focused on further development of the technique. Intention of possible evolution of the technique to imaging spectroscopic ellipsometry is proposed.
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Study of the sterilization effect of temperature and UV light present in dielectric barrier discharge
Kramárová, Petra ; Grossmannová, Hana (referee) ; Kozáková, Zdenka (advisor)
The main theme of this bachelor thesis is to study the effect of temperature and UV radiation to the total sterilizing effect of dielectric barrier discharge. Sterilization is a process, which can eliminate all forms of life. The presented bachelor thesis discusses plasma sterilization, which is one of the method, which are suitable for sterilization of heat and chemical sensitive materials. This sterilization method is effective on the wide spektrum of procaryotic and eucaryotic microorganisms. Basically, the main inactivation factors for cells exposed to plasma are heat, UV radiation and various reactive species. In my thesis a dielectric barrier discharge (DBD) operating at atmospheric pressure was used for the sterilization of the samples. Plasma was generated in argon and nitrogen. According to the previous measurement the best sterilization results were observed using plasma power input 2 562,96 mW•cm-3 (argon) a 2 044,44 mW•cm-3 (nitrogen), therefore the same plasma power input was applied during our measurement. Fungi spores of Aspergillus niger were used as model organisms. Whatman paper No. 1st was used as the carrying medium. Each sample series was exposed to plasma for 5, 10, 20, 40, 60, 120 and 180 s. In order to separate the effect of UV radiation generated by DBD the quartz glass transmitting UV radiation was used. During the plasma exposition one of the sample was covered with the quartz window and the other sample was directly exposed to the plasma, afterwards the results were compared. The microbial abatement observed for the samples covered by quartz window was much lower than for the the samples directly exposed to the plasma. In first case the UV radiation and temperature is the main inactivation mechanism, while in the latter one the synergistic effect of UV radiation, temperature and active species is employed. Furthermore the effect of plasma sterilization increases with increasing the plasma exposition time. While comparing results observed for the argon and nitrogen, better results were achieved in argon. Effects of UV radiation and temperature were studied separately. The temperature between the DBD electrodes was measured by means of thermocouple. Afterwards the samples were placed in an oven and exposed to the same temperature as was measured between the electrodes. By comparing the results of heat treated samples and plasma treated samples it can be assumed that the influence of the temperature during the sterilization process in DBD was negligeable. The discharge parameters were studied by means of the optical emission spectroscopy.
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Influence of external fields on electric field and photocurrent in CdTe detectors
Rejhon, Martin ; Franc, Jan (advisor)
This thesis is focused on a study of CdTe and CdZnTe semiconductor detectors working under high flux of radiation. We studied experimentally an influence of high flux of X-rays and optical radiation on polarization of the detector. The polarization phenomenon decreases the efficiency of the detector due to a screening of an applied electric field by a space charge accumulated at deep levels due to a trapping of photogenerated carriers. In order to measure the electric field profiles in the detectors we employed a method based on cross polarizers technique and Pockels effect. The main objective of this work was to study the possibilities of an optical de-polarization of CdTe and CdZnTe detectors for different photon energies of additional light, its dynamics and physical origin. We have found that detectors can be de-polarized by above bandgap light. Moreover, CdZnTe detector can be depolarized by near infrared light and in a pulse mode. The de- polarization is associated with a compensation of the space charge at deep traps.
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FRP composite materials resistance to the effects of selected corrosive environments
Mičkal, Petr ; Prokeš,, Jan (referee) ; Bodnárová, Lenka (advisor)
This thesis deals with monitoring of the durability of FRP reinforcements in alkaline environments with differing temperature exposures. The theoretical part of the thesis consists of a general description of the FRP composites, the manufacturing of these FRP reinforcements using pultrusion technology, the resistance of these composites in aggressive alkaline environments, and the influence of temperature on the speed and manner of degradation. In the experimental part of this thesis, the FRP reinforcements were placed in an alkaline environment tempered at different temperatures (20 °C, 40 °C, 60 °C). Subsequently, any optical physical changes of the reinforcements were described and evaluated by the use of optical microscopy and the destructive tests of these reinforcements.
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