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Study on the influence of plasma activated water on seed germination
Vozár, Tomáš ; Zlámalová Gargošová, Helena (referee) ; Kozáková, Zdenka (advisor)
This bachelor thesis deals with study on the influence of plasma activated water on wheat seed germination. After interaction with the plasma, the water changes its composition and obtain new properties that are useful in agriculture. The theoretical part is divided into two parts. The first part of the theory is dealing with basic knowledge about plasma, its properties, and possibilities of plasma generation in laboratory conditions. In the second part, the work deals with plasma activated water – PAW. The preparation of plasma activated water is described in details as well as its physical-chemical properties and composition with respect to the PAW possible applications. The aim of the experimental part of this work was to prepare plasma activated water in three different plasma systems and apply it on wheat seeds. These three ways of activation used direct and indirect interaction of plasma with water surface. After the seeds were germinated, the influence of plasma activated water on seed germination and quality of crops was observed and compared to control samples. The influence of different ways of water activation was also evaluated. Results show positive effects of plasma activated water on the seed germination and it also increased the quality of crops. Next steps in this research should be the transfer of this experiment from the laboratory scale on the Petri dish to the pot experiments in soil.
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Metallization of technical plastics for lightweight traffic components with reduced fuel consumption
Sanetrníková, Dominika ; Boušek, Jaroslav (referee) ; Šimůnková, Helena (advisor)
The beginning of this thesis is dedicated to polymeric materials, which include plastics an composites. Plastics are shortly divided into two groups, thermoplastics and thermosets. The following part is the use of plastics and composites in traffic industry and briefly this work focuses on techniques of recycling of this materials. This work also focuses on the techniques of thin film deposition, electroless plating, electrodeposition as well and plating in the vacuum environment. special techniques of thin film deposition are also mentioned shortly. The coatings of polymer including cleaning and surface activation is introduced using various techniques including plasma treatment. The surface treatment of polyetheretherketone (PEEK) is included too. The final part describes performed experiments and discussion of results.
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Diagnostic of nitrogen post-discharge by optical emission spectroscopy
Kabeláčová, Kateřina ; Slavíček,, Pavel (referee) ; Mazánková, Věra (advisor)
The aim of this thesis is diagnose post-discharge nitrogen plasma with optical emission spectroscopy. There is long interest of investigated of nitrogen post-discharge plasma and study how to use it in theory as well as in practice. All results were measured with method of optical emission spectroscopy of post-discharge plasma. Discharge was generated by direct-current voltage generator with flowing regime. In this thesis was used for different series of experiments. First experiment was performed with adding water vapour into argon plasma. Measuring was processed at constant current 140 mA, voltage 1.5 V and pressure 1 000 Pa. It was changed flow rate and for each individual flow rate was measured in range 1–25 cm from end of active discharge. Second experiment was with adding nitrogen into argon plasma. Measuring was processed at constant current 140 mA, voltage 1.5 V and pressure 1 000 Pa. We were changing flow rate of nitrogen (0,2 sccm, 0,4 sccm and 0,8 sccm). For each individual flow rate was same experiment with changing distance from active discharge. Third experiment was about adding mercury vapour into nitrogen post-discharge. Measuring was processed at constant current 120 mA, voltage 3.5 V and pressure 1 000 Pa. Measuring was performed with two configuration: with diaphragm and without it. Last experiment was about adding air into argon plasma. Measuring was processed at constant current 140 mA, voltage 1.0 V and pressure 1 000 Pa. Temperature of outer face of tube was measured by thermocouple and infrared thermometer, was measured for last two experiments (argon – air and nitrogen). During experiments with pure nitrogen was visible phenomenon called pink afterglow which is manifested by noticeable increase pink coloration. Optical emission spectrums post-discharge was take at various range of wavelength. At argon with water vapour was 280–600 nm and at adding nitrogen into argon was at range 320–500 nm. At added mercury vapour into nitrogen was 320–600 nm. For experiment argon – air was wavelength range 320–600 nm. From results of experiments were designed dependencies of calculated intensity from measured spectra on distance from active discharge. Also were constructed dependencies of measured temperature on distance from active discharge.
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Control and measurement unit for plasma generators
Paulovics, Petr ; Boušek, Jaroslav (referee) ; Zemánek, Miroslav (advisor)
The diploma thesis deals with the issue of plasma generators. Specificantlly, the work focuses on the design of HMI devices for plasma generators, including the design of the control part of the generator. The main advantage of controlling the plasma generator using an HMI device is the ability to quickly change important parameters. The HMI device allows convenient switching of the generator output frequency without the need to interfere with the wiring, which leads to higher efficiency when working with the plasma generator. Another advantage of the HMI device is the display of all important information on the LCD display. The work deals with the basic theory of plasma and its use, the division of microcontrollers and the description of their peripherals, the selection of components used and their wiring. The last part of the work is devoted to the software of the plasma generator.
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Optimization of the experimental parameters for laser induced breakdown spectroscopy (LIBS) of selected plant samples
Prochazka, David ; Novotný, Karel (referee) ; Kaiser, Jozef (advisor)
This diploma thesis describes optimization of the experimental parameters for Laser-induced breakdown spectroscopy of plant samples. First part deals with the theoretical method of LIBS and explains the principles and terms. In the next part there is described device which was used for measurements. Main part of diploma thesis describes creation of program for measurement-automation. Main task of program was to solve the connection of autofocus on the sample with the sample automatic movement. Furthermore are described and elaborated specific measurements for optimization of the experimental parameters for Laser-induced breakdown spectroscopy of plant samples.
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Corrosion layers removal in low-pressure plasma
Kujawa, Adam ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
A plasmachemical reduction of corrosion layers on copper was studied. In this case two series of copper samples were prepared and putted in two corrosive environments for one week. The first corrosive environment contained a concentrated nitric acid and the second environment contained a concentrated sulfuric acid. Samples thus prepared were ready to be plasmachemicaly treated. The plasmachemical reductions took place in low-temperature, low-pressure, non-isothermal, high-frequency-inducted hydrogen plasma on the Faculty of Chemistry in University of Technology in Brno. The discharge was generated in continual or pulse mode with changeable pulse ratio. To monitor the reduction process an optical emission spectroscopy was used. The radiation from plasma discharge was measured by an optical spectrometer in the intervals of 1 to 10 minutes. An object of our concern in collected spectrum was the radiation of OH radicals with electromagnetical wavelenght in a range of 305 – 330 nm, and which were produced in a reaction between the hydrogen radicals and the oxygen atoms, contained in the corosion layers. A rotation temperature of plasma was calculated from the spectrums of OH radicals in a dependence of discharge conditions. Gathered findings will give us a better knowing of this conservation technique, that is used for treatment of the corroded surfaces of the archeological artifacts, and will also allow more provident appliance of this method on a copper historical objects.
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Unconventional machining processes
Exnerová, Jitka ; Mouralová, Kateřina (referee) ; Kalivoda, Milan (advisor)
This thesis deals with the methods of the unconventional machining. The first part outlines the history of the machining methods, their characteristic and use follows. The second part aims at the method of the water jet, its technology, safety use, its advantages and disadvantages. Subsequently the thesis presents selected companies dealing with water jet cutting technology. At the end the thesis presents the environmental impact of the water jet cutting.
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Production of handrail holder
Ryšavý, Jan ; Varjan, Matúš (referee) ; Peterková, Eva (advisor)
Economic and technological analysis of possible methods of production real part. The basic theoretical knowledge of selected production methods and their application in practice. The division of production methods for various production series of part using economic evaluation.
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