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Studium syntézy ethylesteru kyseliny mléčné z jejích solí / The Study of Ethyllactate Synthesis from Lactic Acide SaltsHlavatá, Daniela January 2015 (has links)
This diploma thesis deals with senthesis of lactic acid ethyl ester from slats of lactic acid. The literature review has been processed in the theoretical part of the diploma thesis. It is focused on manufacturing technologies of lactic acid esters, mainly on ethyl lactate by conventional and non-conventional ways of producing. Also the literature review involves producing of lactic acid and slats of lactic acid by fermentation because subsequently is possible produce ethyl lactate from that two substances. The laboratory apparatus for preparation of ethyl lactate and methyl lactate has been designed, realized and verificated function of it in the experimental part. There were carried out laboratory experimnets for production ethyl lactate and methyl lactate in this apparaturs.
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Použití nasycených vyšších mastných kyselin v technologii vínaChvalinová, Klára January 2017 (has links)
Sulfur dioxide has been used in the wine industry for many centuries due to its antimicrobial and antioxidant effects. However, the problem is that SO2 is a major allergen and when consuming higher doses, health complications (such as headaches, stomach aches, asthmatic problems) may occur. It is therefore important to find a suitable substitute, or rather a supplement to this substance. One of the options is the use of saturated higher fatty acids (HFA). These substances naturally occur in nature and a small amount of them is formed by yeasts themselves during fermentation. Thanks to HFA the yeast cells´ lipid membranes are changed (their liquidity), resulting in cell degradation, slowing of metabolism and thus slowing down the fermentation until it is stopped. In this experiment, a mixture of HFA, octanoic, decanoic and dodecanoic acid, ratio 2:7:1, respectively, was used at doses of 5, 10, 20, 30, 40 and 60 mg/l, with two variants of the application SO2, 20 mg/l or 40 mg/l. The HFA residues, the corresponding ethyl esters and the influence on sensory properties of the wine were observed. The results of this experiment show (or HFA residues) that the more HFA is added, the more they are absorbed by the yeasts. At the same time there was a very slow esterification in time and thus a low influence on the aroma of wine. Sensory analysis showed the HFA dose of 20 mg/l as the limit from which we are able to recognize differences in HFA doses. There was also an influence of sludge particles. The longer the wine matures, the less sludge particles it contains, hence the HFA are bound on the yeast cells, and thereby their influence on wine sensory is reduced.
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Stanovení hladin mastných kyselin ve vybraných tkáních / The determination of fatty acids level in chosen tissuesKynclová, Kamila January 2021 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Kamila Kynclová Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Title of Diploma Thesis: Determination of fatty acids levels in selected human tissues Fatty acid are an essential part of many metabolic processes in the body. The theoretical part of the the thesis presents primarily omega-3 and omega-6 fatty acids, their general characteristics, metabolism and their effect on various disease. The roles of fatty acid in cancer, neuropsychiatric and inflammatory diseases are described here. The thesis also mentions the method of gas chromatography, which was used to determine the levels of fatty acids. The experimental part of the thesis includes method, chromatographic analysis and results. 13 fatty acids in 7 different tissues were analyzed: subendocardial tissue, liver parenchymal tissue, kidney and adrenal tissue, skeletal muscle tissue, adipose and brain tissue. Tissues were collected from 20 healthy, suddenly deceased, cadavers. Donors were divided into two groups according to age. The obtained data were statistically processed and divided according to individual fatty acids. In the end the results between the two groups were evaluated with a possible explanation of the...
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Stanovení perfluorovaných organických kyselin v půdách chromatografickými metodami / Stanovení perfluorovaných organických kyselin v půdách metodou plynové chromatografieOkáľová, Zuzana January 2014 (has links)
A method employing solid-liquid extraction with methanol and solid-phase extraction (SPE) clean-up step using Supelco SupelcleanTM ENVITM -Carb 3 mL cartridges (0.25 g graphitized carbon adsorbent) followed by gas chromatography - mass spectrometry with negative chemical ionization (GC-NCI-MS) has been optimized and applied for determination of ultratrace concentrations of C6 - C12 perfluorinated carboxylic acids (PFCAs) in soil samples. A sophisticated multifactorial statistic method, response surface methodology, employing 1/16 fractional factorial design and the face centered central composite design as well has been applied to find the significant parameters which influence the extraction procedure of PFCAs and SPE clean-up step and to set the optimum extraction and clean-up levels of eight parameters evaluated yielding the maximum extraction recovery of all PFCAs. The analyte extraction recoveries and the limits of detection and quantification have been obtained. The recoveries of individual PFCAs were within a range from 85 to 100 % for analyte spiked concentration level of 1.1 ng g−1 and within a range from 91 to 107 % for analyte spiked level of 2.1 ng g−1 . The values of limits of detection were 1.9 - 3.0 pg g−1 and limits of quantification 6.4 - 10.1 pg g−1 . This analytical method has...
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Optimalizace chemické analýzy vybraných složek materiálů historických uměleckých děl / Optimization of chemical analysis of selected components in material of historical artworksPekař, Martin January 2014 (has links)
The simplification of the historical pieces of work samples' treatment is described in the dissertation. The recent methods have been inappropriate therefore, modification of the treatment was necessary. The dammar and copal resin, important restoration materials, were used in the experiment. HPLC-MS, HPLC-ELSD, GC-FID, GC-MS and pyrolysis GC- MS were applied. The concentration of fatty acids in the historical sculpture was determined by GC-MS, and it was compared to the content of fatty acids inside an egg. For identification of monosaccharide in the gum, GC-MS (hexamethyldisilazan, trimethylchlorsilan, and pyridine) is the suitable method. GC-MS determines the same composition of dammar resin as stated in the cited sources. The simple process for the samples' treatment was designed.
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Tvorba elektronických studijních opor pro moderní vyučování chemie / Creation of electronic materials for chemistry educationVáňová, Petra January 2014 (has links)
Creation of electronic materials for chemistry education Bc. Petra Váňová Faculty of Science, Charles University in Prague, 2014 The theme of my thesis is formation of educational instruments/tools for distance education and e-learning which at the same time can be inspirational for teachers of present learning. The theoretical section elaborates on the problems of distance education and e-learning. Furthermore, it describes Moodle, the system for teaching management. For the purpose of the applied section two teaching units were created during the class of Didactics of Organic Chemistry (MC280P06) at Department of Teaching and Didactics of Chemistry, Faculty of Science, Charles University in Prague. The two units focus on the problematic of carboxylic acids and their derivatives. Beside the information about these topics, the contents of the teaching units should provide the students with an insight into modern study tools which increase the effectiveness of distance education as well as present learning. The teaching units are supplemented by study texts, Power Point presentations, handouts with key answers, projects/designs of chemical experiments applying theoretical knowledge to practical level, and a test designed for verifying the improvement of the course participants. The study tools were...
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Deriváty TACN s aminofosfinátovými pendantními skupinami / TACN derivatives bearing aminophosphinate pendant armsBeranová, Tereza January 2016 (has links)
The aim of this work was studying of the coordination properties of TACN macrocyclic derivatives with aminophosphinate pendant arms. Two ligands were prepared, one with two pendant arms NODPam and one with three pendant arms NOTPam. Because of degradation of ligand NODPam during its synthesis, only the ligand NOTPam was studied further. Acid-base properties of ligand and termodynamic stability of aluminium and gallium complexes were studied. Formation and disociation studies were performed with the complexes. Coordination of fluoride ions to aluminium complex was studied using ion selective fluoride electrode. Finally coordination of complex AlFx with ligand NOTPam was studied using 19F and 27Al NMR spectroscopy. Selected experiments were made also with ligand NOTA. Key words: macrocyclic complexes, positron emission tomography, phosphinic acids
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Využívání a efektivita aktivizačních metod v chemickém vzdělávání / Use and effectiveness of activation methods in chemistry educationPražienka, Miroslav January 2012 (has links)
CHARLES UNIVERSITY IN PRAGUE - Faculty of Science Department of Teaching and Didactics of Chemistry Albertov 3, 128 40 Praha 2, Czech Republic Use and effectiveness of activation methods in chemistry education Bc. Miroslav Pražienka mprazienka@seznam.cz Executed pedagogical survey reflects the requirements of modern pedagogy and didactics - the teacher should have a new approach to teaching, both from a technical standpoint, both in the methods. At present, preparation of future teachers, but also in lifelong adult education teachers, computers are preferred, modern electronics (and everything associated with them) and such methods, where the pupil is actively involved in teaching and not just a passive "recipient". For the purposes of my thesis was, therefore, a wide range of teaching aids (PowerPoint presentations, worksheets, educational teaching games, demonstration experiments, tests, including methodologies and manuals), through which pupils were taught. Before and after instruction was given them knowledge and skills test, which was then evaluated. They were also sampled pupils from other primary schools and the results were compared. At the beginning of the survey were established two hypotheses (knowledge and skills gradually decreases with increasing time from the subject and taught for a...
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Polymorfismus vybraných enzymů jako faktor ovlivňující složení mléčného tuku / Polymorphism of some enzymes as factor affecting milk fat compositionKLOJDA, Martin January 2019 (has links)
The aim of this diploma thesis was to determine allele and genotype frequencies for g.10329C>T (A293V) polymorphism in the SCD1 gene in dairy cow populations, establish effects of this locus on milk production traits and fatty acids composition. At first, allele and genotype frequencies were determined. Subsequently the effect of this polymorphism on milk production traits was proved and effects of this polymorphism were demonstrated as well. For the determination allele and genotype frequencies the PCR/RFLP technique was applied. In this diploma thesis the effect of polymorphism g.10329C>T (A293V) on milk production traits was demonstrated as well as the effects of this polymorphism on fatty acids composition. The findings following from this diploma thesis show economical and health benefits of this SCD1 locus.
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Validace nutričních parametrů uvedených na obalech vybraných potravinPláteníková, Markéta January 2014 (has links)
The main purpose of this diploma thesis was to study legislative requirements about marking food products with nutrition labels and summarize the activities and procedures of supervising organizations connected to problematic of goods marking. One of the goals was to briefly describe technological and producing methods of selected food - ham, cheese, kephir milk, baby food with fruit, wafer, bread, wholemeal puffed bread and chocolate. Next goal was to evaluate the risks of food consumption with deceptive nutrition labels. In the practical part of this thesis I have determined quantity of saccharides, lipids, proteins and salt in selected food products by standard methods. Simple saccharides were determined by Schoorl's method and starch volume by Ewers's method. Lipids were determined by Soxhlet's extraction and after put through derivatization. In gas chromatograph (GC) were detected fatty acids. Apart from the Soxhlet's extraction was made also extraction according to Hara and Radin (1987) for comparison. Proteins were determined by method using nitrogen according to Kjehdal with adjustments according to Winkler. The amount of salt was detected analytically by argetometric precipitating titration. Determination the volume of nutritive parameters was made in three ranks of selected products. From obtained results were evaluated possible risks, which might be caused by consumption of food products with deceptively stated nutritive labels.
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