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Polyethylenterepthalate Copper Plating for Conductive Structures Realisation
Chmela, Ondřej ; Zatloukal, Miroslav (referee) ; Starý, Jiří (advisor)
The content of this master’s thesis are methods of pretreatment and coating of the surface of PET to produce conductive copper structure and quality control. Thesis also includes theoretical analysis of these methods. Physical and chemical techniques of surface pretreatment methods are discussed in the theoretical part as well as methods making surface of substrate conductive, the subsequent galvanic copper plating and quality control of coating and testing of the adhesion between layers. The experimental part focuses on two methods of the polymer material surface pretreatments. The properties of these pretreatments were evaluated by using the atomic force microscopy and detection of surface energy by wetting and contact angle measurements. The surface is making conductive with cathode sputtering and electrochemical coating of copper. Adhesion of layers is tested mainly with scratch test and other methods. The results of these sub-operations are used for the realization of multi-layer conductive structures.
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Insulation and dielectric properties of water
Grill, Jiří ; Frk, Martin (referee) ; Špinka, Jiří (advisor)
This master´s thesis deals about insulation and dielectric properties of water. It describes the structure of water, covalent and hydrogen bonds. It outlines primary chemical and physical properties of water and then it describes parameters of water - dynamic viscosity, conductivity, surface tension, pH and also describes dielectric properties - dielectric loss, loss factor, permittivity, polarization. Part of the work is practical section, which includes measurements of deionized water, destilled water, tap water and shows primary dependence such as dependence loss factor on frequency or relative permittivity on frequency.
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Deposition and characterization of SA layers from vinyltriethoxysilane
Veverka, Miroslav ; Veselý, Michal (referee) ; Čech, Vladimír (advisor)
Development of composite material is very much progressive sector and leads to evolution of material with new property. This type of material has one, but important deficiency. It is small adhesion armature to matrix. My study is sight on improvement adhesion the surface by deposition self assembled (SA) monolayer from organosilanes. Property of this layer, like thickness, surface tension, homogenity and wettability, was evaluated by the contact angle measurement and spektroscopical elipsometri.
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Study of surface tension of systems applied in ultrasonography.
Říkovská, Klára ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
Surface tension of sonography systems was investigated using several experiments. These experiments were comprised of measurements of surface tension using BPA-800P tensiometer. The influence of surface tension of commercial substance SonoVue®, which contains in its structure two types of phospholipids, was studied more detailed. Other phospholipids were studied to comparison with SonoVue®. All substances were dissolved in saline (0,15 M NaCl). Effect of gas type on microbubbles formation and surface tension was investigated. Some samples were studied using du Nüy ring method. It was found that gas constructing the microbubbles (air or SF6) has no impact to the surface tension value. Production of foam on the surface of solutions has an impact on the value of the surface tension. This foam degreases the surface tension. Gas pressure is significant to comparison of measured data.
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Investment casting waxes and measurements of their properties with regard to simulation software
Bochníček, Štěpán ; Mikulka, Vít (referee) ; Kosour, Vojtěch (advisor)
Today, the use of simulations is increasing in order to reduce cost and complexity of production and also to prevent product defects. For this purpose, we use simulation programs, such as ProCAST. This program is designed for simulation of casting parts. In my bachelor thesis I focused on the methods of casting lost wax, where the model is made of wax mixture. In each simulation we have to obtain and specify the properties of the material to casting. I described these properties and methods of measurement in this bachelor thesis.
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Dynamic surface tension in study of hyaluronan-surfactant interactions
Herzog, Milan ; Žídek, Jan (referee) ; Pekař, Miloslav (advisor)
The main task was to characterize interactions between negatively charged biopolymer sodium hyaluronate and two cationic surfactants: cetyltrimethylammonium bromide (CTAB) and tetradecyltrimethylammonium bromide (TTAB). Interactions between sodium hyaluronate and these surfactants are based on their different charge and can be detected by changes of surface tension. The influence of constant addition of sodium hyaluronate (MW = 90 and 1400 kDa) on interface tension values at increasing bubble lifetime was observed. For this purpose, the maximum bubble pressure method was choosen. The measurements were performed in water and in 0,15 mol•l-1 NaCl solution. The obtained results can be used as for description of dynamic properties of hyaluronate-surfactant systems as, e.g., in targeting drug delivery.
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Influence of the preparing of a biopolymer-surfactant system on its aggregation behavior.
Pilgrová, Tereza ; Sedláček, Petr (referee) ; Pekař, Miloslav (advisor)
To study the effect of the method of preparation of biopolymer-surfactant on the aggregation properties several experiments were designed. Closer investigation was made on native hyaluronan-cetyltrimethylammonium bromide (CTAB) system. The system has been studied in the phosphate buffer in aqueous and saline solutions. The effect of the order of substances addition in the samples, the influence of different methods of preparation of certain concentrations of the solutions or the effect of dissolving powdered biopolymer and surfactant on the contrary, the resulting system were investigated. Fluorescence intensity was measured for all prepared samples and its changes were investigated. Pyrene and Nile red were used as fluorescent probes. Some samples were also measured by tensiometer. Measurement of surface tension was based on the method of divorcing the ring from the surface. It was found that the order of the mixing of solutions has a significant effect on the aggregation properties of the system and its appearance. Further effects were detected on the prepared samples by dissolving powdered biopolymer surfactants and vice versa, and environmental influences of the polarity of the system. It was found that sodium chloride abolished the effects of interactions in the system. Effect of method of preparation of certain concentration of CTAB in phosphate buffer is reflected only slightly.
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Gliding Arc
KALA, Jaroslav
The thesis is focused on increasing the surface tension of polyethylen, using plasma. A gliding arc was chosen for this surface modi cation. The theoretical part includes an overview of gas discharges, their classi cation, properties and technical applications, and deals with an in uence of surface tension on surface modi cations of materials. The experiment is explained in the practical part, a jet analysis carried out before the experiment is described. Results of the experiment are presented.
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Material hydrophility and hydrophobicity measurements
SEDLÁK, Jiří
The aim of this thesis is to find out using a method based on the size of the contact angle as changes over time surface free energy density polyethylene. Measured samples of discharges were adjusted by varying plasma and increased its surface tension. The theoretical part deals with the surface tension, contact angle and the Young's equation, which describes the relationship between wetting angle and energy at the interface states of matter. This work also mentions the ways in which the measurement is made. In the practical part of the thesis there is described not only the process of measuring, but also the own experiments and their results.
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