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Analysis of elements in nutrition supplements
Motlová, Tereza ; Navrátilová, Jana (referee) ; Vitoulová, Eva (advisor)
This bachelor thesis deals with food supplements, mineral elements and their determination in dietary supplements. The aim of this thesis was to elaborate a literature review focused on the food supplements, mineral elements, which are used in food supplements, and methods for determination of mineral elements in nutrition supplements. Forepart of this bachelor treats of food supplements, their basic categories, mineral elements which are contained in nutrition supplements and their effects in case of their oversupply (at high doses) or lack (at low concentrations) in a human body. Other part of this thesis is concerned with options of mineral elements determination in food supplements. Thereinafter, the thesis deals with ways of preparing samples for determination and analytical methods which are used for determination of mineral elements in nutrition supplements. Food supplements are foodstuffs which serve to direct consumption. Supplements differ from casually foodstuffs by high contents of vitamins, mineral elements and others matters which have nutrition and physiological effect. Food supplements are manufactured in order to achieve a diet completion of common user with positive impact on human health.
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Speciation analysis of selenium in selenized yeast
Motlová, Tereza ; Vitoulová, Eva (referee) ; Diviš, Pavel (advisor)
The aim of the theses was determination of selenium species in yeast Saccharomyces cerevisiae cultivated in medium with added inorganic form of selenium (Sodium Selenite). Concentrations of Sodium Selenite in cultivation medium were 0,1; 1; 10 and 100 mg.l-1. Cultivation was undertaken in fermenting tub for period of 72 hours. Cultivated yeasts were extracted by use of enzymes and subsequently the species of selenium in particular parts of yeasts were determined. In order to determine selenium species, the method of high-performance liquid chromatography in combination with atomic fluorescent spectrometer and technique of hydride generation was used. Having analysed different fractions of the yeasts Saccharomyces cerevisiae it was ascertained that during cultivation the sorption of selenium occurred in form of Se4+ in cell membranes while in cytoplasm no inorganic forms of selenium were found. Furthermore, it was stated that yeasts Saccharomyces cerevisiae are able to metabolically change inorganic forms of selenium to organic forms (selenomethionine), while these forms are present in cytoplasm and they are likely to be bound to proteinic structures of cell membranes. An increase of concentration of Se4+ in cell membranes could be observed as a result of increasing concentration of Sodium Selenite in cultivation medium. In proteinic structures the concentration of organic selenium forms increased only to concentration 10 mg.l-1 of Sodium Selenite in cultivation medium.
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Pyroelectric effect in technical applications
Motlová, Tereza ; Tofel, Pavel (referee) ; Hadaš, Zdeněk (advisor)
The focus of this bachelor thesis is pyroelectric effect and its use for energy harvesting. Mathematical model of pyroelectric harvester was described, and then recreated in MATLAB-based graphical programming environment Simulink. Various applications of pyroelectric materials were researched, and their use as sources of electricity was evaluated.
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Production of polymer optical elements and their analysis by electron microscopy
Motlová, Tereza ; Sobola, Dinara (referee) ; Pokorná, Zuzana (advisor)
There is a great demand nowadays for optical components with high quality and efficiency, yet as lightweight and low-priced as possible. These requirements are met by micro-optical elements. The aim of this work is to design and manufacture a polymer micro-optical element for aberration correction in a Czerny-Turner type spectroscope that had previously been constructed at the Institute of Scientific Instruments of the Czech Academy of Science. The design was carried out with the help of of the ZEMAX OpticStudio ver. 21 optical design software. The element was manufactured using the technique of two-photon polymeration and nanoimprint lithography. Surface quality, profile verification and presence of defects was checked using confocal microscopy and scanning electron microscopy. The micro-optical element was then successfully incorporated into the spectroscope.
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The evaluation of the influence of lubricants on the compaction process of tableting mixtures with microcrystalline cellulose
Motlová, Tereza ; Svačinová, Petra (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Mgr. Tereza Motlová Title of Thesis: Evaluation of the influence of lubricants on the compaction process of tableting mixtures with microcrystalline cellulose This thesis evaluates the influence of various lubricants on the compaction process of tableting. Microcrystalline cellulose Avicel® PH 102 was used as filler. This cellulose was mixed with 2 % of magnesium stearate, Aerosil® 200, Syloid® AL-1 FP and Syloid® 244 FP EU, respectively. The evaluation was carried out using a compaction equation and stress relaxation tests. Parameters for evaluation of compaction equation were obtained by calculation from three-exponential equation. It is possible to determine the different phases of the compression process, its mechanism or to evaluate the compressed material using these parameters. The compression process is divided into three phases - pre-compression phase, the phase of elastic deformation and plastic deformation phase. The results show, that all lubricants accelerate the first stage of rearrangement of the particles and also the phase of elastic deformation. The speed of volume reduction in the phase of plastic deformation is similar...
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Compressibility of powder mixture with antifrictional agents.
Motlová, Tereza ; Řehula, Milan (advisor) ; Ďoubal, Stanislav (referee)
The tablet is formed by the effect of compression force during compression process. The supplied energy is consumed in the formation bonds between particles and molecules of compressed material. For that reason it is important to determine the size of energy to be applied for forming tablets. The most common method for detecting the size of the energy is rating of force- displacement profile. In this work were monitored two factors affecting energy compressing. It was a compression pressures of size 5, 10 and 15 kN and research of the influence of frictional materials on the energy compressing. These effects were observed for tablets compressed from microcrystalline cellulose Avicel PH 102. As the frictional material was used magnesium stearate, Aerosil 200, Syloid AL - 1 and Syloid 244. As the parameters of energy were evaluated the following parameters: pre-compression energy E1, plastic energy E2, elastic energy E3, energy used for the compression Elis, total energy Emax and plasticity. The results of this work indicates that compression pressure increases the studied energy except plasticity, where is reduced of this parameter. The presence of friction substances reduces parameter E1, E2, Elis, Emax and plasticity and on the contrary increases the parameter E3.
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Pyroelectric effect in technical applications
Motlová, Tereza ; Tofel, Pavel (referee) ; Hadaš, Zdeněk (advisor)
The focus of this bachelor thesis is pyroelectric effect and its use for energy harvesting. Mathematical model of pyroelectric harvester was described, and then recreated in MATLAB-based graphical programming environment Simulink. Various applications of pyroelectric materials were researched, and their use as sources of electricity was evaluated.
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The evaluation of the influence of lubricants on the compaction process of tableting mixtures with microcrystalline cellulose
Motlová, Tereza ; Svačinová, Petra (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Mgr. Tereza Motlová Title of Thesis: Evaluation of the influence of lubricants on the compaction process of tableting mixtures with microcrystalline cellulose This thesis evaluates the influence of various lubricants on the compaction process of tableting. Microcrystalline cellulose Avicel® PH 102 was used as filler. This cellulose was mixed with 2 % of magnesium stearate, Aerosil® 200, Syloid® AL-1 FP and Syloid® 244 FP EU, respectively. The evaluation was carried out using a compaction equation and stress relaxation tests. Parameters for evaluation of compaction equation were obtained by calculation from three-exponential equation. It is possible to determine the different phases of the compression process, its mechanism or to evaluate the compressed material using these parameters. The compression process is divided into three phases - pre-compression phase, the phase of elastic deformation and plastic deformation phase. The results show, that all lubricants accelerate the first stage of rearrangement of the particles and also the phase of elastic deformation. The speed of volume reduction in the phase of plastic deformation is similar...
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Compressibility of powder mixture with antifrictional agents.
Motlová, Tereza ; Řehula, Milan (advisor) ; Ďoubal, Stanislav (referee)
The tablet is formed by the effect of compression force during compression process. The supplied energy is consumed in the formation bonds between particles and molecules of compressed material. For that reason it is important to determine the size of energy to be applied for forming tablets. The most common method for detecting the size of the energy is rating of force- displacement profile. In this work were monitored two factors affecting energy compressing. It was a compression pressures of size 5, 10 and 15 kN and research of the influence of frictional materials on the energy compressing. These effects were observed for tablets compressed from microcrystalline cellulose Avicel PH 102. As the frictional material was used magnesium stearate, Aerosil 200, Syloid AL - 1 and Syloid 244. As the parameters of energy were evaluated the following parameters: pre-compression energy E1, plastic energy E2, elastic energy E3, energy used for the compression Elis, total energy Emax and plasticity. The results of this work indicates that compression pressure increases the studied energy except plasticity, where is reduced of this parameter. The presence of friction substances reduces parameter E1, E2, Elis, Emax and plasticity and on the contrary increases the parameter E3.
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Speciation analysis of selenium in selenized yeast
Motlová, Tereza ; Vitoulová, Eva (referee) ; Diviš, Pavel (advisor)
The aim of the theses was determination of selenium species in yeast Saccharomyces cerevisiae cultivated in medium with added inorganic form of selenium (Sodium Selenite). Concentrations of Sodium Selenite in cultivation medium were 0,1; 1; 10 and 100 mg.l-1. Cultivation was undertaken in fermenting tub for period of 72 hours. Cultivated yeasts were extracted by use of enzymes and subsequently the species of selenium in particular parts of yeasts were determined. In order to determine selenium species, the method of high-performance liquid chromatography in combination with atomic fluorescent spectrometer and technique of hydride generation was used. Having analysed different fractions of the yeasts Saccharomyces cerevisiae it was ascertained that during cultivation the sorption of selenium occurred in form of Se4+ in cell membranes while in cytoplasm no inorganic forms of selenium were found. Furthermore, it was stated that yeasts Saccharomyces cerevisiae are able to metabolically change inorganic forms of selenium to organic forms (selenomethionine), while these forms are present in cytoplasm and they are likely to be bound to proteinic structures of cell membranes. An increase of concentration of Se4+ in cell membranes could be observed as a result of increasing concentration of Sodium Selenite in cultivation medium. In proteinic structures the concentration of organic selenium forms increased only to concentration 10 mg.l-1 of Sodium Selenite in cultivation medium.
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