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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.
1

Hodnocení rozkladu různých typů degradovatelných plastů v laboratorních podmínkách kompostování

Spěšná, Lucie January 2015 (has links)
The thesis aims to determine the actual degradability or biodegradability of selected samples of plastic bags in a controlled composting environment as well as the impact of biodegradable plastics on the final quality of compost. The theoretical part of the work describes the characteristics of synthetic polymers. The following chapter is devoted to biodegradable plastics and outlines their types, certification options as well as the normative support in the Czech Republic. In addition, it briefly characterizes the composting process itself and defines phytotoxicity. The practical part evaluates the experiment carried out on samples of plastic bags during the composting process and summarises the result of compost quality obtained by phytotoxicity testing.
2

Syntéza konjugovaných polymerů odvozených od polyacetylenu / synthesis of conjugated polyacetylene based polymers

Duchoslavová, Zuzana January 2010 (has links)
Mostly new acetylene based monomers were prepared. All monomers were prepared by the means of standard spectroscopic methods. All monomers were successfully polymerized using standard metathesis TaCl5 based catalyst. Prepared polymers were characterized by the means of GPC/GPC-MALLS chromatography and standard spectral methods. Fluorescence properties of all prepared compounds were also studied: quantum fluorescence yields were determined and excitation and emission fluorescence spectra were recorded. Polymerization on modern metathesis Grubbs-Hoveyda catalytic systems of all prepared monomers was also tested. These reactions were only partially successful and only low molecular weight oligomers in mediocre yields were obtained.
3

Polymerizace a cyklotrimerizace arylacetylenů katalyzovaná komplexy rhodia / Polymerization and cyclotrimerization of arylacetylenes catalyzed by rhodium complexes

Vystrčilová, Lucie January 2010 (has links)
No description available.
4

Přímá arylace a její využití při přípravě supramolekulárních polymerů / Direct arylation and its application in supramolecular polymer synthesis

Loukotová, Lenka January 2014 (has links)
This thesis is divided into two parts. In the first part there is reported palladium- catalysed regioselective direct arylation of benzofurans with arylsulfonyl chlorides as the coupling partner to C2 carbon. The best reaction conditions of this reaction were investigated, then the influence of various arylsulfonyl chloride substituents to the reaction and finally it is reported direct arylation of C2-arylated benzofuran to C3 carbon to give diarylated benzofuran with different aryl substituents. In the second part, there is reported the synthesis of 2-(hydroxymethyl)-5,7-bis{5- [(2,2':6',2''-terpyridine)-4'-yl]thiophen-2-yl}-2,3-dihydrothieno[3,4-b][1,4]dioxin and modification of its sidechain. As a starting material of the synthesis it was used commercially available 4'-bromo-(2,2':6',2''-terpyridine). The synthetic sub-steps included Suzuki cross- coupling, bromination and C-H bond activation. Then it was also reported the complexation of synthesized oligomer with zinc and iron cations.
5

Farmaceutické aplikace polyesterů jako nanonosičů léčiv / Pharmaceutical applications of polyesters as drug nanocarriers

Staňková, Petra January 2018 (has links)
Charles University Faculty of Pharmacy in Hradci Králové Department of Pharmaceutical Technology Consultant: PharmDr. Ondřej Holas, PhD. Student: Petra Staňková Title of Thesis: Pharmaceutical applications of polyesters as drug nanocarriers Nanoparticles are nowadays intensively studied and perspective type of a drug carrier. Its potential is based on a possibility of targeted drug delivery and controlled drug release. The theoretical part is about nanoparticles types, polymers derived from α-hydroxyacids (PLA, PGA, PLGA). Focus is given on methods of nanoparticles preparation: dispersion of preformed polymers or the polymerization of monomers. The modification of particles surface and practical use of nanomedicine in healthcare are described in other chapters. The research in experimental part is focused on the influence of different types of PLGA and their weighing on the size, polydispersity, nanoparticles zeta potential and encapsulation efficiency of rhodamine B. Nanoparticles were prepared by nanoprecipitation method or by solvent evaporation method. The Zetasiser ZS 90 device was used to measure the size of the nanoparticles and to measure zeta potential. The result of the research shows the most suitable weighing for creation of nanoparticles is 25 mg. The samples of this weighing show a...
6

Povrchová úprava plastů v nábytku

Pelikánová, Ivana January 2018 (has links)
The thesis deals with the quality of surface finishing of individual types of plastics and their suitability for worktops of furniture. The work defines the properties of plastics and requirements for the surface finishing of furniture. In the experimental part, the properties of plastic surfaces are verified by performing tests on ABS, PC, PMMA, PP and PVC samples. The output is to evaluate the properties and meet the requirements of test surfaces for use on the worktops.
7

Studium degradace biokompatibilních kopolymerů / Study of degradation of biocompatible copolymers

Oborná, Jana January 2011 (has links)
This diploma thesis is focused on biocompatible polymers degradation study. Copolymers were studied based on poly(lactic-co-glycolic) acid and poly(ethylene glycol) PLGA-PEG-PLGA and further these copolymers modified with itaconic acid ITA-PLGA-PEG-PLGA-ITA. This paper investigated the influence of pH phosphate solution on the degradation of polymers. Degradation of polymers occurred at 37 °C in phosphate solution with pH 4.2, 7.4 and 9.2. High performance liquid chromatography with UV-VIS detection of diode-array type was used for quantitative determination of lactic acid and glycolic acid as the final degradation products. For qualitative identification of additional degradation products were used tandem connection liquid chromatography and mass spectrometry. Gel permeation chromatography with refractive index detector was used to determine the molecular weight decrease polymer chain after the degradation.
8

Fotogenerace nosičů náboje v substituovaných polyacetylenech / Photogeneration of charge carriers in substituted polyacetylenes

Jex, Michal January 2013 (has links)
We present an improved model of charge carrier photogeneration in π-conju- gated polymers with weak intermolecular interactions based on the model of Arkhipov. It includes quantum effects affecting the creation of charge transfer states, which occurs as an intermediate step in the free charge carrier photo- generation process. The electrostatic potential between the electron and the hole and transfer integrals needed for the calculation of the potential barrier for the charge transfer state dissociation are calculated quantum-chemically. We apply our model on experimental data of the charge carrier photogenera- tion efficiency in poly[1-trimethylsilylphenyl,2-phenyl]acetylene to explain its dependence on applied electric field. We eliminate several problems of the previous model. We are able to fit experimental data with just one set of parameters in the whole interval of the applied electric field. We do not have to consider several intervals of the electric field separately as in the previous work and reduce the number of needed parameters to three. Key words π-conjugated polymers, charge carrier photogeneration, photoconductivity 1
9

Příprava biodegradovatelných polymerních nanočástic / Biodegradable polymeric nanoparticles preparation

Bacskaiová, Silvia January 2018 (has links)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: PharmDr. Ondřej Holas, Ph.D. Student: Silvia Bacskaiová Title of Thesis: Biodegradable polymeric nanoparticles preparation The present scientific progress in an important rate conduces to nanomedicine development, which aims to reengineering of cancer pharmacotherapy and other substantial diseases. The main intention of this graduation thesis is the study of surface-active chemical's effects on the final properties of nanoparticles. The theoretical part is focused on the nanoparticles likedrugs vehicles, synthesis of biodegradable nanoparticles, themselves applications in the cancer therapy, diseases accompanied by inflammations, vaccination and for another different purposes. The theoretical part also contents characterization of active and passive goal- directed distribution by diseases, microencapsulations, synthesis of nanoparticles by polymerization and from previously synthesized polymers and definition of physical- chemical properties of nanoparticles. The experimental part is more extensive and concerned with the optimalization of reaction conditions of nanoparticles synthesis, with selection of advisable concentracion and type of surfactant. In the experimental part were...
10

Využití syntetických protilátek v imunohistochemii / Use of synthetic antibodies in immunohistochemistry

Tomečková, Kristýna January 2021 (has links)
This diploma thesis deals with the optimization of the preparation of molecularly imprinted (MIP) nanoparticles doped with metal ions, selective for the selected protein. In this work, the model protein – chymotrypsinogen A was chosen as a template. The free radical polymerization method was used for the preparation of molecularly imprinted nanoparticles. Dopamine was used as a functional monomer because it is able to bind metal ions to each other. It also undergoes very rapid oxidative polymerization under alkaline conditions without the need for the addition of polymer reaction initiators. MIP optimization was performed by capillary electrophoresis with UV-Vis detection. The MIP thus prepared can serve as recognition elements in immunohistochemical analyzes that use LA-ICP-MS as a detection method. Their applicability for immunohistochemistry was studied using the dot block method.

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