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Hydrogels modified by amphiphilic structures
Heger, Richard ; Sedlařík, Vladimír (referee) ; Kráčalík, Milan (referee) ; Pekař, Miloslav (advisor)
The submitted dissertation deals with the influence of amphiphilic structures on hydrogel properties. Additions of various amphiphilic substances associated with the formation of highly ordered structures affect the mechanical, transport and structural properties of hydrogels. The main inspiration for this type of work was living tissue, more precisely the extracellular matrix, which is often mimicked by hydrocolloids, and its high orderliness is responsible for its unique properties. The knowledge obtained from this tissue was applied to the hydrogel systems studied in this work. Various cross-linked hydrogel matrices (physically cross-linked agarose and gelatin, ionically cross-linked alginate and chemically cross-linked mixture of polyvinyl alcohol and chitosan) were suitable representatives for this work. These hydrogel systems were modified by the addition of various amphiphilic substances. The human body’s own phospholipid, lecithin, or variously charged more classic surfactants (CTAB, SDS and Triton X-100). Experimentally, this work is divided into three areas, the study of mechanical properties using rheology, the description of transport properties via release and flow experiments using various model drugs (rhodamine 6G, eosin B, amido black 10B, methylene blue and riboflavin), and morphological characterization using SEM. The characterization of hydrogel systems was supported by other techniques used in this work, such as drying and swelling experiments or gas sorption.
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Production technology of the connector body from recykled material
Brhel, Michal ; Sedlařík, Vladimír (referee) ; Kandus, Bohumil (advisor)
Study developed during the Master's degree studies of Mechanical Engineering deals with the use of recycled plastic in the injection molding and its influence on the mechanical properties of the mold. Examined product is used in the automotive industry as a connector body. The housing is manufactured from a plastic material, polyamide. The annual production volume of 3 000 000 pieces. According to tests specified in standard USCAR2 regrind influence on mechanical properties and dimensions was evaluated. After the technical evaluation of the project, research was also judged from economic point of view. In this task, savings with the different content of the recycled material during production was calculated. The final chapters justify change of properties and they are proposing the use of recycled materials in practice.
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Corporate Information Strategy
Sedlařík, Vladimír ; Maštalíř,, Roman (referee) ; Koch, Miloš (advisor)
This thesis analyzes the YouTube service and describes its main deficiencies. Based on theoretical methods and analyses, its main goal is to design a service that will solve the main YouTube problems, build a company around this service and introduce this service to the market. This service will not replace YouTube, but it will supplement it. Further, this work will suggest a possible structure, strategy and information strategy of this new company and its estimated financial results in the first few years.
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Hyaluronan ion complexes
Cimalová, Jana ; Sedlařík, Vladimír (referee) ; Pekař, Miloslav (advisor)
This diploma thesis is focused on the study of physical and chemical properties of hyaluronan and cationic surfactant. As the cationic surfactant Septonex was used. The influence of the environment on the system, the effect of molecular weight of hyaluronan, and its concentration was studied. Then, the study of the influence and the effects of concentration of Septonex on the interaction of hyaluronan-surfactant followed. Different methods of measurement were chosen to characterize these ionokomplexes. The critical micelle concentration of the surfactant itself was measured, and then also with the addition of hyaluronan by spectrofluorimetry with fluorescent probe pyren. It was found, that hyaluronan forms gel with Septonex. On this basis, gels were prepared for three different molecular weights of hyaluronan – 300 kDa, 806 kDa and 1697 kDa. Gels were prepared in a ratio of hyaluronan – surfactant 1:1. In gels prepared in this way, the influence of environmental water and 0.15 M NaCl was studied and it was found that at 0.15 M NaCl clear gels are formed. Selected samples of the gels were then measured with oscillatory testing and the rheological behavior of gels of Septonex was studied. As the last method the turbidimetric measurement was chosen, which characterized the turbidity point in the gradual addition of Septonex to sodium hyaluronate solution. Again, the effect of the molecular weight of hyaluronan and its concentration in two environments - water and 0.15 M NaCl was evaluated. It was found that 0,15 M NaCl suppresses formation of turbidity and formation of precipitates.
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Increase of Sales Efficiency Using Multimedia Technology
Sedlařík, Vladimír ; Groligová, Ivana (referee) ; Kříž, Jiří (advisor)
This work is aimed at multimedia advertising techniques, evaluating their efficiency and financial performance. Important aspects are listed to be followed when exposed to a potentialcustomer. The work is an assessment of the current advertising for the Western Town s.r.o. near Boskovice and advertising by a video presentation. There are examples of selected companies that offering advertising using LED screens in busy places in Brno. Economic aspects are analyzed and forecasts of return or profit. The work is accompanied by a video presentation of advertising in this amusement park created in iMovie.
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Business Plan
Vysloužil, Daniel ; Sedlařík, Vladimír (referee) ; Khateb, Fabian (advisor)
This master's thesis deals with the establishment of a company that deals with the creation propagational materials with the help of modern technology. The theoretical part is conceived as a literature search. The result is to assess the market environment, narrative marketing approach, financial analysis and timetable for the project.
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Biocompatible Amphiphilic Compounds and their Interactions with Polymers
Burdíková, Jana ; Sedlařík, Vladimír (referee) ; Bakoš, Dušan (referee) ; Pekař, Miloslav (advisor)
This work is focused on the study of interaction between hyaluronan and high-biocompatible amphiphilic molecules. Using fluorescent probe method, screening of the interaction of cationic lipid 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP), mixture of this cationic lipid with zwitterionic lipid, 1,2-dipalmitoyl-sn-glycero-3-phosphochloline (DPPC), with hyaluronan, both native and hydrophobically modified was carried out. Results showed the self-aggregation of DPPC and DPTAP independently on lipids ratio in the mixture and the interaction of DPTAP and DPPC/DPTAP aggregates with hyaluronan at specific ratio of DPTAP and hyaluronan concentration. Physical properties of formed membranes and the influence of cholesterol were also investigated at different DPPC and DPTAP concentration ratio. Last but not least, the non-ionic surfactant-DPPC systems were studied, namely, the size of the formed aggregates, the thermodynamics of solubilisation and the interaction with native hyaluronan.
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Biocompatible Amphiphilic Compounds and their Interactions with Polymers
Burdíková, Jana ; Sedlařík, Vladimír (referee) ; Bakoš, Dušan (referee) ; Pekař, Miloslav (advisor)
This work is focused on the study of interaction between hyaluronan and high-biocompatible amphiphilic molecules. Using fluorescent probe method, screening of the interaction of cationic lipid 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP), mixture of this cationic lipid with zwitterionic lipid, 1,2-dipalmitoyl-sn-glycero-3-phosphochloline (DPPC), with hyaluronan, both native and hydrophobically modified was carried out. Results showed the self-aggregation of DPPC and DPTAP independently on lipids ratio in the mixture and the interaction of DPTAP and DPPC/DPTAP aggregates with hyaluronan at specific ratio of DPTAP and hyaluronan concentration. Physical properties of formed membranes and the influence of cholesterol were also investigated at different DPPC and DPTAP concentration ratio. Last but not least, the non-ionic surfactant-DPPC systems were studied, namely, the size of the formed aggregates, the thermodynamics of solubilisation and the interaction with native hyaluronan.
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Ionic polyacetylene type polymers and polymer networks by catalyst-free quaternization polymerization
Faukner, Tomáš ; Zedník, Jiří (advisor) ; Balcar, Hynek (referee) ; Sedlařík, Vladimír (referee)
(Doctoral Thesis, 2016, Mgr. Tomáš Faukner, IONIC POLYACETYLENE TYPE POLYMERS AND POLYMER NETWORKS BY CATALYST FREE QUATERNIZATION POLYMERIZATION) The composition and structure of a series of ionic π-conjugated poly(monosubstituted acetylene)s prepared via catalyst-free quaternization polymerization (QP) of 2-ethynylpyridine (2EP) activated with equimolar amount of alkyl halide [RX = ethyl bromide, ethyl iodide, nonyl bromide and haxadecyl (cetyl) bromide] as a quaternizing agent (QA) have been studied in detail. The performed QPs gave ionic polymers well soluble in polar solvents, with approximately half of pyridine rings quaternized, which implies that also non-quaternized monomers were involved in the process of QP. The configurational structure of polyacetylene main chains was suggested based on 1 H NMR, IR as well as Raman (SERS) spectral methods. The QPs in bulk gave more expected irregular cis/trans polymers while the QPs in acetonitrile solution gave high-cis polymers. A series of prepared symmetrical bi-pyridylacetylene based monomers has been polymerized via QP approach resulting into a series of new ionic π-conjugated poly(disubstituted acetylene) type materials. It is therefore obvious that the mechanism of quaternization activation frequently applied on monosubstituted...
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Synthesis and characterization of new polymers of substituted acetylenes
Sivkova, Radoslava Parusheva ; Vohlídal, Jiří (advisor) ; Strachota, Adam (referee) ; Sedlařík, Vladimír (referee)
New procedures for preparation of polyacetylenes with highly luminescent naphthalimide groups that might be potentially utilized in optoelectronics and sensors are developed within the framework of present doctoral thesis. The procedures provide luminescent a) linear polyacetylenes that can be processed from solutions, and b) mesoporous network polyacetylenes with high pore volume. Two paths to soluble polyacetylenes are used: (i) copolymerization of ethynyl- functionalized naphthalimide (monomer PN) and a monoethynyl aromate catalyzed with [Rh(nbd)acac], and (ii) modification of poly(disubstituted acetylene)s carrying -chloroalkyl pendants involving the exchange of chlorine atoms for azido groups and subsequent "click"- reaction of Huisgen type of azido groups with ethynyl groups of PN. The PN does not homopolymerize but copolymerizes with ethynylaromates. The highest possible molar fraction of the PN units in copolymers is of 0.5, which suggests the absence of PN dyads or longer sequences in copolymers and the alternating arrangement of PN units in the copolymers of the composition of 0.5. Surprisingly, ethynylarenes that give insoluble homopolymers gave soluble copolymers with PN. The modification procedure requires knowledge on the effect of the monomer structure symmetry and substituent...
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