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Determination of volatile isoprenoids as water stress markers of spruce resistance against bark beetle
Slušná, Michaela ; Kalinová, Blanka (advisor) ; Hoškovec, Michal (referee)
Isoprenoids are important components of conifer resin and represent an important part of constituted defence system against herbivores and pathogens. Drought is one of the most important factors that influences the tree physiology and resitance. Due to decreased turgor of resin canal cells, the water insufficiency affects the pressure of the resin and thereby the ability of trees to physically prevent pathogen or herbivore invasion by effective outpouring of the resin. In addition, drought can also change the resin composition and thus can influence the quality of volatiles emitted by the tree. The Norway spruce, Picea abies, is the predominant species of production forests in moderate climate zone. Bark beetles, Ips typographus, represent the most important pest species of spruce. In general, pioneer bark beetles use host volatiles to orient themselves toward the tree suitable for colonization and in many species host volatiles synergize bark beetle aggregation pheromones. Thus the host volatile composition could affect significantly host colonization. This diploma thesis studied the influence of drought on the production and composition of isoprenoid volatile organic compounds in 80 - 100 years old spruce trees. Using I. typographus antennae as biological detectors, we also studied which resin...
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Preparation and polymerization ethynyl pyridine based monomers
Faukner, Tomáš ; Zedník, Jiří (advisor) ; Hoškovec, Michal (referee)
A group of monomers based on disubstitued ethynylpyridine (3-PyCCPh-4-t-Bu, 2-PyCCR, R = 4-t-BuPh, 2-Py, n-Bu) and 4-tert-butyphenylethynyl (4-t-BuPhCCPh-p-OR, R = SiPh2-t-Bu, Si-i-Pr3) were prepared by Sonogashira cross-coupling reaction (PdCl2[(PPh3]2/CuI). All of these monomers were charakterized by IR, UV/vis and NMR spectroscopy. Ethynylpyridine based monomers were polymerised by quarternization (ethylbromid was used as a quarternization agent) and by Grubbs-Hoveyda 2nd generation catalyst. As a product of the quarternization were obtained oligomers compounded by 2 - 13 monomers units (Mw: 1600 - 6000, Y 70%). Only low molecular weight oligomers were also obtained by Grubbs-Hoveyda 2nd generation polymerization (Mw: 400 - 1500, Y 34 %). Monomers based on 4-tert-butyphenylethynyl were polymerized by TaCl5/Bu4Sn/Toluen catalytic system. In that case were obatined polymers (Mw: 64 000 - 200 000, IP = 2,3 -3,9, Y 75 %). Products of polymeryzations were charakterized by GPC, IR, UV/vis and NMR spectroscopy.
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Activity of new nickel-complexes in coupling reactions
Plaček, Martin ; Svoboda, Jan (advisor) ; Hoškovec, Michal (referee)
In this work, we report the study of the catalytic activity of newly prepared coordination compounds of nickel(II) (complexes were prepared by prof. Kyritsis, University of Athens). The activities in model reactions of Kumada and Suzuki coupling and polymerization of 2,5- dibromo-3-hexylthiophene were tested. For Kumada coupling, the activity is comparable with known complex [Ni(dppp)Cl2]. On the other hand, selected complexes exhibit only limited activity for Suzuki coupling. GRIM polymerization of 2,5-dibromo-3-hexylthiophene was successful. Properties of prepared polymers are comparable with polymers prepared via known route with [Ni(dppp)Cl2].
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Preparation and polymerization ethynyl pyridine based monomers
Faukner, Tomáš ; Zedník, Jiří (advisor) ; Hoškovec, Michal (referee)
A group of monomers based on disubstitued ethynylpyridine (3-PyCCPh-4-t-Bu, 2-PyCCR, R = 4-t-BuPh, 2-Py, n-Bu) and 4-tert-butyphenylethynyl (4-t-BuPhCCPh-p-OR, R = SiPh2-t-Bu, Si-i-Pr3) were prepared by Sonogashira cross-coupling reaction (PdCl2[(PPh3]2/CuI). All of these monomers were charakterized by IR, UV/vis and NMR spectroscopy. Ethynylpyridine based monomers were polymerised by quarternization (ethylbromid was used as a quarternization agent) and by Grubbs-Hoveyda 2nd generation catalyst. As a product of the quarternization were obtained oligomers compounded by 2 - 13 monomers units (Mw: 1600 - 6000, Y 70%). Only low molecular weight oligomers were also obtained by Grubbs-Hoveyda 2nd generation polymerization (Mw: 400 - 1500, Y 34 %). Monomers based on 4-tert-butyphenylethynyl were polymerized by TaCl5/Bu4Sn/Toluen catalytic system. In that case were obatined polymers (Mw: 64 000 - 200 000, IP = 2,3 -3,9, Y 75 %). Products of polymeryzations were charakterized by GPC, IR, UV/vis and NMR spectroscopy.
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Determination of volatile isoprenoids as water stress markers of spruce resistance against bark beetle
Slušná, Michaela ; Kalinová, Blanka (advisor) ; Hoškovec, Michal (referee)
Isoprenoids are important components of conifer resin and represent an important part of constituted defence system against herbivores and pathogens. Drought is one of the most important factors that influences the tree physiology and resitance. Due to decreased turgor of resin canal cells, the water insufficiency affects the pressure of the resin and thereby the ability of trees to physically prevent pathogen or herbivore invasion by effective outpouring of the resin. In addition, drought can also change the resin composition and thus can influence the quality of volatiles emitted by the tree. The Norway spruce, Picea abies, is the predominant species of production forests in moderate climate zone. Bark beetles, Ips typographus, represent the most important pest species of spruce. In general, pioneer bark beetles use host volatiles to orient themselves toward the tree suitable for colonization and in many species host volatiles synergize bark beetle aggregation pheromones. Thus the host volatile composition could affect significantly host colonization. This diploma thesis studied the influence of drought on the production and composition of isoprenoid volatile organic compounds in 80 - 100 years old spruce trees. Using I. typographus antennae as biological detectors, we also studied which resin...
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Activity of new nickel-complexes in coupling reactions
Plaček, Martin ; Svoboda, Jan (advisor) ; Hoškovec, Michal (referee)
In this work, we report the study of the catalytic activity of newly prepared coordination compounds of nickel(II) (complexes were prepared by prof. Kyritsis, University of Athens). The activities in model reactions of Kumada and Suzuki coupling and polymerization of 2,5- dibromo-3-hexylthiophene were tested. For Kumada coupling, the activity is comparable with known complex [Ni(dppp)Cl2]. On the other hand, selected complexes exhibit only limited activity for Suzuki coupling. GRIM polymerization of 2,5-dibromo-3-hexylthiophene was successful. Properties of prepared polymers are comparable with polymers prepared via known route with [Ni(dppp)Cl2].
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The Natural Law Conception - its potentiality and limitations
HOSKOVEC, Michal
This diploma thesis deals with the Thomas Aquinas´s Conception of Natural Law. The fundamental content of thesis is the Czech translation and critical Commentaries of English written articles. Thesis is divided into three parts. There is a theoretical foundation for Natural Law Conception and Thomas Aquinas themes in the first part, the Critical Commentaries of translated articles in the second part and the translated articles in the third part of diploma thesis. Translated articles are the philosophy studies of Natural Law and its relation to the Lawmaking, the Logic of Ethical Discourse and the Human Rights. There are copies of original English written articles as diploma thesis attachments.
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