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Vývoj nových aplikačních forem huminových látek pro zemědělské a environmentální aplikace / Development of New Application Forms of Humic Substances for Agricultural and Environmental applicationKratochvílová, Romana January 2020 (has links)
The new forms of superabsorbent polymers (SAP) on the base of acrylic acid were developed and studied in this thesis. The SAP are focused on agricultural and environmental applications. While they are applied to the soil, SAP can prevent water losing and they become a reservoir of humidity in case of dry season, moreover in combination with fertiliser they play role of controlled release medium. Eight various samples of SAP were experimentally prepared by networking of partially neutralized acrylic acid. Potassium peroxydisulfate was used as the initiator and N,N–methylenebisacrylamide as the crossing agent. Some of samples contained addition of second monomer of acrylamide. All of them were enriched by fertilisers – natural lignohumate or synthetic NPK or combination of both. The swelling characteristics of prepared samples were investigated in conditions of various ionic strength. The influence of xerogels’ particles size on swelling properties was also observed. The viscoelastic characteristics of hydrogel form of all SAP were determined by using of rotation rheometer. The changing of viscoelastic properties were studied in dependence on time, on freezing and on repeating swelling cycles. On top of that the controlled releasing ability of SAP was tested due to three modelling experiments. The biological activity of all polymer products was tested at the end of the thesis. All samples of SAP were incorporated into the artificial soil and the ability of the water retention in the soil was observed. The growing experiments were running by using of corn plants. The size and the mass of each plant were measured and branching of the root was objectively evaluated by programme Harmonic and Fractal Image Analyzer.
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Aplikace bylinného extraktu do vhodného potravinářského produktu / Application of herbal extract into suitable food productChmelařová, Adéla January 2020 (has links)
This master’s theses deals with a production and characterization of hard candies, a type of non-chocolate sweets. Methods of candies production were optimised with focus mainly on boiling temerature which significantly affects product consistency and stability. Production process optimisation was based on methods of sensoric analysis and Karl-Fishcher titration used to determine the water content in the product. Plant extracts Plectranthus amboinicus and Aronia melanocarpa which were applied to hard candies are rich source of bioactive compounds upon which prepared candies were characterised. Optimal conditions for candies production were – boiling temperature 155 °C, volume of citric acid 0,4 %, volume of Plectranthus extract 2 % and volume of Aronia extract 3 %. There were 42 volatile compounds identified in a sample containing 2 % of Plectranthus extract. Based on their content , the most significant compounds were carvacrol (8,44 %), carotol (1,47 %) and levomenthol (0,99 %). Total content of polyfenols was measured to be 7,10 ± 0,55 mgg-1 per 1 g of hard candy sample, antioxidant activity of a sample was 66,19 ± 1,80 gml-1. It was identified that 42 of volatile compounds were present inside the sample with 3 % of Aronia extract. The most significant being carotol (30,67 %), menthol (1,52 %) and thymol (1,39 %). The overall presence of polyphenols was measured to be 13,87 ± 1,12 mgg-1 per 1 g of the candy sample, the antioxidant activity of the sample was 115,00 ± 2,86 gml-1.
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Vývoj a validace metody stanovení reziduí některých hormonálně účinných látek v biologickém materiálu metodou GC/MS / Method development and validation for the assesment of hormonal active substances residues in biological material by GC/MSZelníčková, Hana January 2008 (has links)
This diploma thesis is focused on the problematics of occurence and quantitative determination of hormonal active substances in biological material. The aim of experimental part was to develope and validate the analytical method, suitable for quantification of hormonal active substances in biological materials. Elaborated method is able to be used for screening determination of some steroid hormonal active substances in urine of farming animals, and for performance confirmative analysis of the same substances in the same matrix on required concentration level. Used method is determined for quantification of steroids in low concentration level in urine of farming animals. Among others performs the criteria of confirmative methods intended for monitoring of residues of hormonal active substances in biological material according to Council Directive 2002/657/EC. Determined parameters of the method answer the supposed values. The method proved to be quite suitable and offered required results. Individual analytes were identified,with certainty, they offer expressive, symmetrical and well separated peaks. This diploma thesis was prepared in Institute for State Control of Veterinary Biologicals and Medicaments in Brno.
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Posouzení ekotoxicity vybraných syntetických vonných látek / The ecotoxicological evaluation of musk compoundsLapčíková, Alena January 2009 (has links)
This master’s thesis is focused on evaluation of synthetic musk fragrances using ecotoxicity tests. Four musk fragrances were tested – Galaxolide, Tonalide, Musk ketone and Musk xylene. Four alternative ecotoxicity tests with living organisms, one standard ecotoxicity test and three fytotests were used for evaluation of ecotoxicity. Alternative tests were performed on crustaceans Daphnia magna and Thamnocephalus platyurus, brine shrimp Artemia salina and rotifer Brachionus calicyflorus. Root growth inhibition test of Sinapis alba, root growth inhibition test of Lactuca sativa, root growth inhibition test of Allium cepa and growth inhibition test of Lemna minor were performed in the terms of fytotests. On the basis of the results the values of EC50, IC50 and LC50 were determined and the ecotoxicity of musk compounds was evaluated.
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Stanovení vybraných vonných látek v potravinách / Assessment of chosen aromatic compounds in foodsŠkopová, Jitka January 2010 (has links)
The thesis deals with the issue of potentially allergenic aroma compounds in food. Aroma compounds suitable for food flavouring are mainly of plant origin. These aroma compounds and their mixtures have a lot of positive and negative effects on human organism. Although the aroma compounds are not among main groups of allergens, several studies indicate a potential risk of allergenic effects of some aroma compounds. The theoretic part of this thesis focuses on aroma compounds of plant origin and gives an overview of 26 the most important fragrance allergens according to the European cosmetic legislation. The aim of the experimental part was to verify the selectivity and appropriateness of the currently used methodology of headspace solid-phase microextraction and gas chromatography-flame ionization detection (HS-SPME-GC-FID) for determination of selected allergenic aromatic active compounds. Secondly, it is to use a proven method for a wide spectrum of real food products.
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Stanovení aromaticky aktivních látek bezu černého / Assessment of aroma active compounds in elderberriesBazgerová, Petra January 2010 (has links)
This diploma thesis deals with the determination of aroma volatile compounds in elderberry. The theoretical part describes the botanical characteristics of elderberry, the incidence and the other known species. Further, this work is focused on the chemical composition of elderberry, there are described in detail the content substances and briefly mentioned are medicinal effects of elderberry. Another theoretical part describes the natural processing of this significant plant and technological production of fruit juices. The second half of the theoretical part deals with the method of determining aroma volatile compounds by gas chromatography in combination with SPME technique, which is suitable for identification of aroma substances. In the experimental part of this diploma thesis SPME-GC method was applied to some samples of elderberry and aroma volatile compounds of individual samples of elderberry were determined.
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Stanovení vybraných vonných látek v kosmetických prostředcích / Assessment of chosen aromatic compounds in cosmeticsNovotná, Petra January 2011 (has links)
This master thesis deals with the assessment of selected fragrant substances in cosmetic products. At the beginning the occurrence, methods of acquiring and application of these substances is described. They are essential components primarily in cosmetic products, however they can cause an allergic reaction in sensitive individuals. The theoretical part of this thesis also describes the cause and the progress of these undesirable effects. There are several hundreds, up to thousands fragrant substances used in the perfume industry, from which 26 was designated by the European regulations as potential allergenic fragrant substances and their content is regulated. Legislative standards as well as the overview of the methods used to determine these fragrances are given here. The experimental part is focused on the development and validation of the separation methods for determining of the selected and potentially allergenic fragrant substances. The method used was a solid phase microextraction using Carboxen/Polydimethylsiloxane fiber combined with a gas chromatography coupled to a flame ionization detector (SPME-GC-FID). Amylcinnamyl alcohol, benzyl alcohol, cinnamyl alcohol, coumarin, lyral, ?-isomethyl ionone were among the determined allergenic substance. Consequently, this method was also applied on 10 selected cosmetic products specimens, in which the linalool and geraniol were identified as the most common allergenic substances.
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Stanovení vybraných vonných látek v potravinách / Assessment of chosen aromatic compounds in foodsAscherová, Adriana January 2011 (has links)
This diploma thesis is focused on aromatic substances occurring in food. The theoretical part describes their characteristics, the use of fragrances of plant origin for flavoring of food and points to their possible negative effects on the human organism. Twenty six potentially allergenic fragrances are thus identified in European legislation and an overview of their physical properties, occurrence and use is also processed in this work.The aim of the experimental part was to develop and validate a method for assessment of fragrances using headspace solid phase microextraction combined with gas chromatography (HS-SPME-GC-FID). The following parameters have been validated : repeatability, linearity, limits of detection (LOD) and limits of quantification (LOQ). The HS-SPME-GC-FID method was finally applied to selected samples of foods commonly available on the market.
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Monitoring obsahu senzoricky aktivních látek v průběhu výroby sýrů / Monitoring of sensory active compounds during cheese productionRyglová, Hana January 2017 (has links)
This work deals with monitoring of sensory active compounds during production of Edam cheeses, i.e. natural hard cheeses with low heat curd, and of processed cheeses, which were produced from Edam cheeses. Sensory active compounds contribute to overal flavour of cheese. They are volatile compounds, which include alcohols, aldehydes, ketones, fatty acids, esters, lactones, terpenes etc. These compounds were identified and quantified using SPME/GC/FID method in the model samples of Edam cheeses and processed cheeses, produced at Tomas Bata University in Zlin. In total 42 volatile compounds were identified, 6 aldehydes, 7 ketones, 15 alcohols, 6 esters and 8 acids. Differences in number of compounds identified, as well as in the contents of them, were found between samples. Effect of pasteurization on the contents and composition of the identified compounds was the most obvious in the samples of matured cheeses. In the samples of processed cheeses the effect of pasteurization was the most obvious in combination with prolonged heating during melting.
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Určení obsahu rozpustných fenolických látek v porostech smrku ztepilého s využitím hyperspektrálních dat / Determination of soluble phenolics in common spruce stands using hyperspectral dataBuřičová, Michaela January 2011 (has links)
The thesis deals with lignin and soluble phenolic determination in Norway spruce foliace using hyperspectral data. A literature overview is focused on the analysis of lignin and soluble phenolics. The practical part focuses on the determination of wavelenghts intervals which are suitable for the detection of lignin and soluble phenolics. There is applied regression analysis for the determination of relationship between the foliage spectra and the content of biochemical substances for the chosen spektrum intervals. Indexes NDLI, mNDLI and RLI were than calculated. HyMap hyperspectral airborne images from 2009 and 2010 for the area of Sokolov, spectral curves of dry matter and fresh branches of Norway spruce and laboratory determination of lignin and soluble phenolics content were the inputs for the analyses. Maps of lignin content in Norway spruce are the final output of the work. Keywords: Norway spruce (Picea Abies), lignin, soluble phenolics, PLS (partial least square) method, multiple Stepwise regression, NDLI
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