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Modification of Polyethylene by Reactive Compounding
Horkel, Ondřej ; Kučera, Jaroslav (referee) ; Petrůj, Jaroslav (advisor)
This Master’s thesis deals with the problematics of radically initiated compounding of polyethylene by 1-vinyladamantane. Theoretical part focuses on the theory of grafting processes and how they are influenced by chosen process parameters, as well as the properties of used monomer. In experimental part, two sets of experiments were designed, in both cases the chemicals used were polyethylene LITEN MB 87, (2,5-dimethyl-2,5-bis(tert-butylperoxy) hexane), also called Trigonox 101, as the initiator, and chemicals called Ionol and Irgafos 168 as stabilizers. The experiments were carried out in a Brabender batch mixer, the temperature was 180 – 185 °C, the reaction time was 5 minutes. The analytic methods used to evaluate the prepared samples’ properties were the tensile testing, the Charpy notch test, measuring of the melt flow index, analyzing the torque during kneading and the analysis of infrared spectra of the samples. By carrying out of these experiments it was found that excessive crosslinking was present with mass fraction of initiator being as low as 2 %. It was also concluded that under these conditions the modification does not improve tensile properties of the material, but it does improve the impact strength, albeit slightly. The influence of the modification on flow properties needs to be investigated further. A presence of vinyl groups was observed in infrared spectra, suggesting the presence of ungrafted vinyladamantane.
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Modification of Polypropylene by Reactive Compounding
Svítil, Jan ; Kučera, Jaroslav (referee) ; Petrůj, Jaroslav (advisor)
Knowledge of radical initiated grafting was summarized in theoretical part. It also contains a part about adamantane, its derivatives and a study of their use in polymer chemistry. In experimental part radical grafted polypropylene was prepared in batch mixer Brabender at 185 and 195 °C, 40 RPM and reaction time 5 min. Initiator 2,5-dimethyl-2,5-bis(tert-buthylperoxy)hexane (Trigonox 101) in concentrations between 0,2 – 4 wt % was used. 1-vinyladamantane was chosen as a monomer and its concetration ranged from 0,75 to 2,24 wt %. Mechanical properties of prepared samples were tested. Sample with content of initiator 0,2 wt % and monomer 1,4 wt % showed increase in notch toughness by 56,3 %, strength by 8,7 %, ductility by 11,5 % and decrease in MFR (230 °C; 2,16 kg) by 29,7 %. Values of torque indicated grafting reactions which couldn’t be proven by use of FTIR method so more suitable methods have been proposed.
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Word-formation processes used by players of online games in writing
KUKAČKA, Tomáš
The content of the bachelor thesis consists of the analysis of word-formation processes used in Internet communication. The bachelor thesis is divided into the theoretical and practical part. The theoretical part focuses on word-formation processes used in English with an emphasis on shortening and abbreviation, as these two processes are being the most often used in Internet communication. Furthermore, the thesis briefly describes the environment of the game World of Warcraft and the communication of its players. The practical part is based on a corpus of data obtained from the game channel called "world chat", where the majority of players' communication takes place. The corpus itself is created using the LancsBox software, which is used to compile a list of the most frequent words used by players, for which their word-formation process is determined. The research aims to compile a ranking of the most frequently used word-formation processes by players.
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Modification of Polypropylene by Reactive Compounding
Svítil, Jan ; Kučera, Jaroslav (referee) ; Petrůj, Jaroslav (advisor)
Knowledge of radical initiated grafting was summarized in theoretical part. It also contains a part about adamantane, its derivatives and a study of their use in polymer chemistry. In experimental part radical grafted polypropylene was prepared in batch mixer Brabender at 185 and 195 °C, 40 RPM and reaction time 5 min. Initiator 2,5-dimethyl-2,5-bis(tert-buthylperoxy)hexane (Trigonox 101) in concentrations between 0,2 – 4 wt % was used. 1-vinyladamantane was chosen as a monomer and its concetration ranged from 0,75 to 2,24 wt %. Mechanical properties of prepared samples were tested. Sample with content of initiator 0,2 wt % and monomer 1,4 wt % showed increase in notch toughness by 56,3 %, strength by 8,7 %, ductility by 11,5 % and decrease in MFR (230 °C; 2,16 kg) by 29,7 %. Values of torque indicated grafting reactions which couldn’t be proven by use of FTIR method so more suitable methods have been proposed.
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Modification of Polyethylene by Reactive Compounding
Horkel, Ondřej ; Kučera, Jaroslav (referee) ; Petrůj, Jaroslav (advisor)
This Master’s thesis deals with the problematics of radically initiated compounding of polyethylene by 1-vinyladamantane. Theoretical part focuses on the theory of grafting processes and how they are influenced by chosen process parameters, as well as the properties of used monomer. In experimental part, two sets of experiments were designed, in both cases the chemicals used were polyethylene LITEN MB 87, (2,5-dimethyl-2,5-bis(tert-butylperoxy) hexane), also called Trigonox 101, as the initiator, and chemicals called Ionol and Irgafos 168 as stabilizers. The experiments were carried out in a Brabender batch mixer, the temperature was 180 – 185 °C, the reaction time was 5 minutes. The analytic methods used to evaluate the prepared samples’ properties were the tensile testing, the Charpy notch test, measuring of the melt flow index, analyzing the torque during kneading and the analysis of infrared spectra of the samples. By carrying out of these experiments it was found that excessive crosslinking was present with mass fraction of initiator being as low as 2 %. It was also concluded that under these conditions the modification does not improve tensile properties of the material, but it does improve the impact strength, albeit slightly. The influence of the modification on flow properties needs to be investigated further. A presence of vinyl groups was observed in infrared spectra, suggesting the presence of ungrafted vinyladamantane.
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Trinominal compounds in French
ČERNÁ, Renata
The subject of the diploma thesis is a characteristic of the French N+N+N compounds of the type "relations parents-enfants" with the use of existing typology for other languages, mainly for Italian. The thesis is divided into two parts. The first part defines the concepts of composition and composite, their distribution based on different criteria. They described graphic, morphological, syntactic, and semantic properties of compounds. The second part of the thesis is dedicated to the practical research in the corpus and subsequent analysis of the acquired data. The last part contains a draft classification of French relational compounds.
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Czech ekvivalents of German composites on the example of selected texts form the field of hotel industry and tourism in Austria
ŠINDELÁŘOVÁ, Andrea
The thesis deals with the differences in Czech and German language in the word-formation, specifically the issue of composite. The main part is devoted to the word-formation of both languages possibilities of vocabulary enrichment are given, important terms of the word-formation are defined and word forming kinds are introduced. It is further processed the theory of composite concepts from different authors. The aim of this work is to demonstrate that in German language appear significantly more composites than sketched options of their Czech equivalents and create a list of Czech equivalent structures. As the basis for this analysis are used texts from the field of hotel industry and tourism in Austria, which are available online on the websites of tourist portals (www.oberoesterreich.at and www.niederoesterreich.at).
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Neology in contemporary French
Mizeráková, Michaela ; Štichauer, Jaroslav (advisor) ; Nádvorníková, Olga (referee)
This master thesis is dealing with the preference of certain categorical structures (VN compounds, nominal syntagmas N de N, N à N and their English equivalent) to denotate a new referent. Its aim is to describe current trends of denominative instrumental neology. The thesis is dividend into two parts: teoretical and practical. Theoretical part provides a brief characteristics of the concerned fields: neology, neologism, compounding, nominal syntagmas and productivity. Practical part includes survey and compares its results with corpus analyses and data obtained from Google browser.
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Neologisms in Arundhati Roy's God of Small Things
Malá, Lucie ; Matuchová, Klára (advisor) ; Topolovská, Tereza (referee)
This thesis focuses on neologisms in the novel The God of Small Things by Arundhati Roy. It aims at describing their morpho-syntactic features, the word-formation processes from which they result, and their contextual function in the analysed text. The original text is compared with the Czech translation and the ways of translating neologisms in Czech are explored. The thesis explores three hypotheses. Firstly, the predominant word-formation process employed in creating neologisms in the text is likely to be compounding. Secondly, the Czech translation is expected to contain fewer neologisms than the original. Thirdly, it is supposed that the distribution of neologisms is not balanced throughout the book, and that their frequency will increase in those chapters which offer the children's perspective. Out of these three hypotheses the first and the third one were confirmed. The validity of the second hypothesis could be neither confirmed nor refuted, for that would require further research on the Czech translation of the text, which was beyond the scope of this thesis.
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Hybrid compound words in the most recent vocabulary
Tesařová, Kristýna ; Bozděchová, Ivana (advisor) ; Lehečková, Eva (referee)
of the bachelor thesis Hybrid compound words in the most recent vocabulary In this bachelor thesis we treat the issue of hybrid compounds not only as an isolated linguistic phenomena, but as a part of language development of contemporary society and its vocabulary, which reflects social expression needs. Theoretical part of the thesis is based on knowledge about language tendencies and about dynamics of the media discourse. The core of the thesis is represented by the treatise on word-formation problems and classification of hybrid compounds with first international constituent complying with meaning "quantity, intensity, extent". In the corpus analysis, which was performed on material of two corpuses of media texts, SYN2006pub and SYN2009pub, were included components with general quantity-intensity semantics (mini-, mikro-, nano-, super-, maxi-, multi-, extra-, ultra-, mega-, giga-, makro-, monstr, top-) and also constituents with numeral meaning (mono-, di-, tri-, tetra-). As a high productive we consider the first set of components, which became involved in many spheres across the vocabulary of current social communication. Here we can find expressive hybrid compound as well as technical terms. These components give us opportunity to capture varied semantic transformations between them (e. g....
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