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Organic-inorganic polymers - synthesis and characterization of hybrid polymers and nanocomposites
Depa, Katarzyna ; Strachota, Adam (advisor) ; Matějka, Libor (referee) ; Sedláček, Jan (referee)
In the first part of this work, silica nanoparticles and alternative or additional filler phases were incorporated into hydrogels based on the temperature-sensitive poly(N- isopropylacrylamide) (PNIPAm). Nano-SiO2-filled porous PNIPAm hydrogels with an enhanced force response (up to 100 g) to temperature stimuli were obtained by increasing several times the pore wall thickness, which was achieved via reducing the solvent (porogen) content during the gels' cryo-synthesis. A similar optimization of the force response was also carried out for analogous gels reinforced by nano-TiO2, in which the reinforcing effect of the filler is weaker. Partial intercalation of amylopectin starch into divinyl-crosslinked bulk as well as porous PNIPAm gels several times improved their extensibility. In case of starch-rich bulk gels, a very fast and extensive one-way deswelling in response to increased temperature was achieved (re-swelling upon cooling is much slower), which is attributed to specific properties of the starch-PNIPAm interface. In doubly-filled bulk PNIPAm/nano-SiO2/starch gels, a very strong synergic reinforcing effect of both fillers is observed, due to specific hydrogen bridging between the three phases. Highly porous cryogels based on PNIPAm/nano- SiO2/starch displayed a highly improved extensibility...
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Porovnání jakosti hlíz v závislosti na různém agrotechnickém postupu pěstování
Kalužíková, Klára
In this work is analyzed the impact of different varieties on the quality of the tubers. Dif-ferent methods are used to evaluate the quality of potatoes. The objective of this thesis was to assess the quality of fifteen different varieties: Adela, Arlet, Dali, Impala, Jolana, Keřkovské rohlíčky, Lada, Magda, Marcela, Margaret, Mirage, Monika, Primarosa, Raphael, Rosara. Fol-lowing parameters were evaluated: starch content, the skin color and tubers and table value. Measurements were performed in the laboratories of the Mendel University on the Institute of food technology. When determining the starch content, the lowest amount has been found in a variety Adele, while the highest in a variety Magda. Regarding skin color measurement, the lightest was variety Rosara and the darkest variety Monika. The detectable difference in raw and cooked tubers was found when determining the color of tubers. Based on the sensory analysis varieties were classified into 3 groups according to boiling type. Boiling type AB was evaluated in the varieties: Rafaela and Rosara. The boiling types BA included varieties: Dali, Keřkovské rolls and Primarosa. Most varieties showed parameters of the boiling type B: Impa-la, Margaret, Monika, Lada, Marcela, Mirage, Adela, Arlet, Jolana.
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Preparation of polysaccharidic binders used in artworks
Švajcrová, Lenka ; Hrdličková Kučková, Štěpánka (advisor) ; Čapek Adamec, Martin (referee)
The main aim of this bachelor thesis was to prepare polysaccharide binders from the chosen kinds of starch (gained from potatoes, corn, wheat, rice and kuzu), Arabic gum and to pigment them. The created samples of the polysaccharide binders were then prepared for further investigation using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and Fourier transform infrared spectroscopy (FT-IR). This work is also focused on the history of the production of starch, its origin, contained substances and growing of the specific plants, from which the starch is obtained from. Furthermore, there is also described the technology process of paintings and other polychromatic arts creation. The technical character of paintings is actually determined by the binders, thus apart from the polysaccharide binders there are also described oil, protein and oil-resin binders. Key words: polysaccharidic binders, starch, Arabic gum, artworks
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Assessment of dairy management in a given farm
BRABENEC, Petr
My diploma thesis is based on the observation of dairy cows nutrition at the farm, nutrition is the most important factor in the production of milk. The introduction of my thesis is focused on a literary overview, which briefly describes the process of digestion, evaluation of nutrients in feed doses and assessment of mixed feed doses. Attention is focused on feed technology in the farm, there was evaluated the intake of dry matter by dairy cows. Dairy cows were fed by total mixed ration (TMR), samples were sent for evaluation to an accredited laboratory and compared to NRC (2001). Another criterion was the evaluation of the particle structure by the Penn state separator (2002), the results were compared with the recommended standard, there was evaluated the homogeneity of the mixed feed structure too. The thesis evaluate composition of the feed ration, where maize silage is predominanting, there is described the variability of starch in maize silage in the monitored period. The thesis describes the evaluation of ungraded starch from bovine feces, samples were again analyzed in an accredited laboratory and evaluated according to the recommended standard, and the probable causes of increased content of unstressed starch in beef excrement are described. Some of the milk production indicators are also mentioned. There was used the informations of Czech and foreign authors.
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Biodegradable plastics
Schifferová, Zuzana ; Jan, Vít (referee) ; Molliková, Eva (advisor)
The aim of this bachelor theses is to discuss the process of biodegradation occurring with biodegradable polymers including factors affecting this process. The theses also introduces some types of biodegradable plastics including their properties. At last it discusses waste management of these plastics and their ecological impact.
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Enzymes partcipating in starch metabolism
Riegelová, Kateřina ; Ryšlavá, Helena (advisor) ; Liberda, Jiří (referee)
Starch is stored in plastids of plant storage organs or in chloroplasts of photosynthetic tissues. This storage polysacharide can be degraded hydrolytically by -amylases (EC 3.2.1.1.) or phosphorolytically by phosphorylases (EC 2.4.1.1.). An extract prepared from tobacco leaves (Nicotiana tabacum L.) was found to disintegrate the dye-labeled starch substrate. The optimal pH of the hydrolytic cleavage was 8.0, while the optimal pH of the phosphorolytic cleavage was 7.0. The highest starch cleavage rate was observed at 55 řC. -amylase is more important for cleavage of starch in tobacco leaves than phosphorylase.
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Hereditary and non-hereditary factors affecting starch content in potato tubers
Malá, Lucie ; Sedláková, Vladimíra (advisor) ; Dvořák, Petr (referee)
This literature review relates to the starch which is presented in potato tubers, and hereditary and non-hereditary factors that influence content of the starch. At the beginning of the work, the attention is paid to the potatoes itself, especially their general characteristics. It should also mention the content of substances in tubers and their impact on human health. Further, the work is focused on the main thema, especialy starch present in potato tubers. Starch has considerable importance for the entire national economy, currently used not only in the starch industry, but it is more frequently used in other industries, for example paper or textile industry. Starch is composed from two important polysaccharides, amylose and amylopectin which are described in details. There are factors, that may influence starch content in potato tubers, like genetic and environmental factors. The simplest genetic factor that can influence the content of starch in potato tubers is crossing. The biosynthesis of starch is very important, which depends on several enzymes that initiate the metabolic pathway. It is pyrophosphorylase, starch synthase (SS), enzymes branched starch (SBEs) and enzymes unbranched starch (DBES). Starch synthase plays an important role here, in particular her isoform GBSS (granule bound starch synthase), which synthesizes amylose. Amylopectin is synthesized by a complex of enzymes SSI, SSII, SSIII, SSIV. The manipulation of single sugar genes metabolism can affect the formation and composition of starch in any variety of potatoes. This manipulation is called transgenesis and her goal is the creation of new potato genotypes. We can produce potato starch with high amylose by inhibiting enzymes SBE A and SBE B. A starch with a high amount of amylose is highy asked from the industry, because starch has unique functional properties. It should be mentioned DNA markers that has connection with the cultivation of potatoes and offers new opportunities for selecting potatoes genotypes. With DNA markers is linked MAS analysis and the associated method PCR polymerase chain reaction method. Another important method is QTL method. The environmental factors which influence the starch content of potatoes, which are mentioned in this work, are drought, light, cold. It should also be noted that even postharvest stress has a negative effect on starch content in potato tubers. Environmental stress affects and changes the yield of the starch.
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Biodegradable Materials and Their Use
Korelusová, Zuzana ; Smejtková, Andrea (advisor) ; Doležal, Vladimír (referee)
The point of this bachelor thesis is to acquaint the reader with the problematic of biodegradable polymer materials. In the main part of this thesis are described their basic types, features and usage in praxis. There will be also presented their basic advantages and disadvantages. These data will be compared with advantages and disadvantages of other basic conventional polymer materials. The last part of the thesis is focused on usage of the biodegradable materials in praxis. In conclusion are summarized all findings and recommendations.
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Nutričně významné látky bramborové hlízy
Habrová, Stanislava
One important source of nutritive substances are potatoes. That is why potatoes are importatnt for human nourishment. They have a significant content of vitamin C, and therefore they have been used as a prevention of scurvy in the past. The aim of this work was to create an overview of the nutritionally relevant sunstances contained in potato tubers. There are also given information about the nutritional importance of potatoes, their material composition, and important substances. Among the important substances of potatoes there are included antioxidants, vitamins, starch and full proteins.
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Hodnocení potenciálních donorů vyšší odolnosti k suchu u pšenice ozimé
Prokešová, Lenka
This work summarises the results of experiments with common wheat lines (T. aestivum L. emed. Fiori et Paol.) during the growing season 2013/2014. Field experiments were carried out in two locations -- Žabčice and Branišovice. Two winter wheat varieties (Etela and Meritto) commonly cultivated in the Czech Republic and 45 Syrian lines with potentially high drought tolerance were evaluated in this work as well as Syrian variety CHAM 6. Spikes analyses were performed and the evaluated characters included awn length, spike length, spike weight, spikelet number, rachis length, rachis segments number, grains per spike number, and grains per spike weight. We focused also on grain yield per plant and the weight of thousand grains. The effect of location was highly significant for both characters -- yield per plant was higher in Žabčice, thousand grain weight in Branišovice. Two quality indicators were assessed -- the content of proteins and starch. As to protein content, all lines and control varieties exceeded the standard given in ČSN 461100-2. The amount of starch was between 66 and 68 %. The response to day length was characterised according to the photoperiod loci Ppd-D1. Photoperiod insensitive allele Ppd-D1a was more common in lines of Syrian origin than sensitive allele Ppd-D1b. To evaluate the tolerance to drought the osmotic potential was determinated and the greatest ability of osmotic adjustment was found in line 27/1.
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