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Microcalorimetric study of interactions between hyaluronan and catanionic vesicular systems
Mach, Jakub ; Pekař, Miloslav (referee) ; Krouská, Jitka (advisor)
Properties of surfactants in water, interactions between oppositely charged surfactants and interactions in system containing didecyldimethylammonium chloride (DDAC), hyaluronan and ion pair amphiphile (IPA) have been studied using isothermal titration calorimetry. For the study of properties of surfactants in water and their mutual interactions, two cationic surfactants have been chosen, namely cetyl trimethylammonium bromide (CTAB) and carbethopendecinium bromide (Septonex), and an anionic surfactant sodium dodecyl sulfate (SDS). For hyaluronan, a molecular weight of 250 450 has been chosen. Critical micelle concentration of the chosen surfactants and enthalpy of the investigated interactions have been determined using the TAM III calorimeter. To prove the interactions in system containing hyaluronan, DDAC and IPA and to determine enthalpy the Microcal PEAQ-ITC calorimeter has been used.
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Study of the influence of polyethylene terephthalate recycling on the quality of the resulting recyclate
Mach, Jakub ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
Plastics and recycling of plastics is a frequently discussed topic. The output of sythetic polymers is rising exponentially every year. In accordance with the sustainable development, development of effective recycling techniques enabling to process these huge amounts of waste and convert it back into useful material is essential. The aim of this work was to study qualitative effects of production methods, various types of recycling processes and degree of degradation of polyenthylene terephtalate on results of differential scanning calorimetry (DSC) analysis. In experimental part, analyzes of 62 regranulates of recycled PET were performed. The samples from various manufacturers differed (manufacturers use different technologies) in terms of mechanical and physico-chemical properties or additives. The results confirmed that the properties of recycled PET have an impact on thermophysical properties recorded using DSC. A simple DSC run enables distinguishing a number of fundamental qualitative properties of PET, in particular crystallinity, melting point and enthalpy, temperature and enthalpy of crystallization and glass transition temperature and in this work we show that their mutual relationship enables to estimate the quality of recycled material and the possibilities of its further use.
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Study of the influence of polyethylene terephthalate recycling on the quality of the resulting recyclate
Mach, Jakub ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
Plastics and recycling of plastics is a frequently discussed topic. The output of sythetic polymers is rising exponentially every year. In accordance with the sustainable development, development of effective recycling techniques enabling to process these huge amounts of waste and convert it back into useful material is essential. The aim of this work was to study qualitative effects of production methods, various types of recycling processes and degree of degradation of polyenthylene terephtalate on results of differential scanning calorimetry (DSC) analysis. In experimental part, analyzes of 62 regranulates of recycled PET were performed. The samples from various manufacturers differed (manufacturers use different technologies) in terms of mechanical and physico-chemical properties or additives. The results confirmed that the properties of recycled PET have an impact on thermophysical properties recorded using DSC. A simple DSC run enables distinguishing a number of fundamental qualitative properties of PET, in particular crystallinity, melting point and enthalpy, temperature and enthalpy of crystallization and glass transition temperature and in this work we show that their mutual relationship enables to estimate the quality of recycled material and the possibilities of its further use.
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Analysis of photo-records of non-fish prey in the diet of selected species of fish-eating birds
Mach, Jakub ; Čech, Martin (advisor) ; Vejřík, Lukáš (referee)
Piscivorous birds are often blamed for causing significant damage to fish stocks. Various methods are used to determine the composition of their food, each of them has limits in its ability to determine the complete food spectrum. This work maps the complete food composition of 14 species of fish-eating birds with a method that is not commonly used. Method used in this work uses analysis of publicly available photos on Google.com. In addition to the complete composition of the food, the species composition of the non-fish part of the prey was also determined, and in the case of the Great Cormorant (Phalacrocorax carbo), also the length of the fishes it catches. The aim of this work is to reveal the usability of this method for these purposes. A total of 2350 retrieved photographs were analyzed. The results obtained by photo analysis are in all cases compared with data in the available literature. For representatives of heron birds (Ardeidae), the analysis of photographs provided good information on the food spectrum of individual birds and on the qualitative composition of the non-fish component. It also provided relatively good information on the diet of the White-tailed Eagle (Haliaeetus albicilla), but the bird part of the prey was slightly underestimated. In the diet of the Great Crested Grebe...
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Microcalorimetric study of interactions between hyaluronan and catanionic vesicular systems
Mach, Jakub ; Pekař, Miloslav (referee) ; Krouská, Jitka (advisor)
Properties of surfactants in water, interactions between oppositely charged surfactants and interactions in system containing didecyldimethylammonium chloride (DDAC), hyaluronan and ion pair amphiphile (IPA) have been studied using isothermal titration calorimetry. For the study of properties of surfactants in water and their mutual interactions, two cationic surfactants have been chosen, namely cetyl trimethylammonium bromide (CTAB) and carbethopendecinium bromide (Septonex), and an anionic surfactant sodium dodecyl sulfate (SDS). For hyaluronan, a molecular weight of 250 450 has been chosen. Critical micelle concentration of the chosen surfactants and enthalpy of the investigated interactions have been determined using the TAM III calorimeter. To prove the interactions in system containing hyaluronan, DDAC and IPA and to determine enthalpy the Microcal PEAQ-ITC calorimeter has been used.
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Zhodnocení spolehlivosti a efektivity metod pro hodnocení škod zvěří na přirozené obnově na LS Buchlovice
Mach, Jakub
The aim of the thesis is evaluating of methods used for assessing damages made by the game on a natural wood restoration in a forestry office in Buchlovice. For assessing damages, data of checking and comparing areas, biting areas with the use of fencings, transects and artifically established cultures. Single methods were evaluated separately and the amount of damages, according to the methods and evaluating of plants, were compared next. The data of 7 checking and comparing areas, 10 biting areas, 11 transects and 10 cultures were used for the evaluation. Three most represented plants were evaluated.
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Analýza možností hodnocení škod na přirozené obnově na LS Buchlovice
Mach, Jakub
This thesis deals with the analysis assess the damage to natural regeneration. For assessment used data from monitoring and comparative areas (hereinafter KSP), to him were evaluated plots (hereinafter ZP), in which the fenced area was always located in oplocence, which was zaplocena natural regeneration. When evaluating those areas were always compared. Were evaluated only areas located in natural regeneration. They assessed the four trees, and most represented beech Fagus sylvatica, further sessile oak Quercus petraea, hornbeam Carpinus betulus and larch Larix decidua. Total evaluated KSP 7 and 7 ZP, all these areas are forest management Buchlovice, district Koryčany, Buchlovice, Staré Hutě, Kostelany and Kvasice.
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Importance and species composition of non-fish prey in the diet of fish-eating predators
Mach, Jakub ; Čech, Martin (advisor) ; Vejřík, Lukáš (referee)
Piscivorous birds are usually considered to be exclusive fish eaters which are responsible for signifiant numerical and economical losses to fish populations. With a method of literary research the importace and species composition of non-fish prey is determine in the diet of selected fifteen species of piscivorous birds. The aim of this work is to determine the extent of non-fish part of the diet of particular piscivorous predators and categorize them on the grounds of differences between size of this part in their diet. Another goal is to determine any effects which can influence amount and species composition of non-fish part of nourishment, and also factors, which can influence obtained results based on the chosen method of analysis. According to the data found, diet of five bird species was composed almost exclusively with fish. Eight other bird species also showed preference for fish prey, but in most of these cases was present also important part of non-fish prey. Two bird species seems to be very oportunistic in case of composition their diet. As factors that can affect the extent of non-fish part in the diet was established especially the prey availability in environment, used method for diet composition analysis, insufficient attention for parts of prey other than fish, or also less...
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