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Silicon substituted calcium phosphate based bioceramic scaffolds
Karkuszová, Karina ; Šťastná, Eva (referee) ; Novotná, Lenka (advisor)
The theoretical part of this bachelor thesis summarizes the current state of knowledge of bioceramic materials based on calcium, phosphorus and silicon. More specifically, it focuses on calcium phosphates, the demands placed on them, the porosity of 3D foams, and biological properties such as biodegradation and bioactivity. 3D bioceramic calcium phosphate foam doped with silicon appears to be a suitable material for use in biomedical applications. It is the silicon that plays a role in the development of healthy bone and the formation of new tissue. Silicon substitutions are important in the field of investigation because they improve the bioassay of phosphate calcium. In the experimental part, calcium phosphate powders were first prepared by the hydroxyapatite and silica fusion reaction. Selected powder contents were 0; 0.1; 1, 2.5, 5, 10 and 20 wt.% SiO2. The samples were sintered at 1100 °C, 1200 °C and 1300 °C. The second part consisted in the preparation of 3D foams by direct penetration with polyurethane and the subsequent characteristics of phase composition, solubility and bioactivity. Bioceramic foams had a highly porous structure. For 42 days, sample behavior in Tris-HCl and simulated body fluid (SBF) was monitored. The results of the experiment have shown that the samples are bioactive and silicon substitution increases phosphate calcium solubility. Therefore, these materials are potentially useful for biomedical applications
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Decomposition and stability of organic matter in soil
Tabaková, Eva ; Enev, Vojtěch (referee) ; Klučáková, Martina (advisor)
In the soil, the plant material is decomposed by several factors. In the process, one part of the carbon returns to the atmosphere as carbon dioxide, whereas another part is stabilised in the soil. The aim of this study is decomposition and stability of organic matter in soil using a simple and innovative TBI method. Through this method, we examined the weight change after the incubation period of 90 days, where biomass of green tea was degraded in cambodia soil. Tea bags have provided us with valuable information on the decomposition and amount of carbon in the soil, because the biomass itself is of organic origin. This information is based on the fact that the soil and the decomposition processes have a direct impact on the change in climatic conditions. Thanks to further analytical methods, elemental analysis, thermogravimetric analysis and infrared spectroscopy with Furier transformation, was found indispensable information about tea composition.
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Identification and detection of defects on the PV system - operational measurement
Leitman, Valentín ; Morávek, Jan (referee) ; Mastný, Petr (advisor)
This work deals with the problem of identifying and detecting faults in photovoltaic systems. This thesis includes theoretical knowledge related to photovoltaic panels, the definition of measured parameters of the PV system and five ways how to identify faults in PV systems. The last part of this bachelor thesis deals with the author's contribution, which is to introduce a system for continuous monitoring data. System for continuous monitoring of data consists of measuring the power output of a photovoltaic panel and measurement using optical diagnostics using thermal camera. In conclusion are summarized individual knowledge, evaluation and recommendation of appropriate measurement methods for the detection of faults in PV systems.
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Use of Advanced Oxidation Processes to remove selected pollutants from the water matrix
Minich, Marek ; Landová, Pavlína (referee) ; Repková, Martina (advisor)
This bachelor’s thesis deals with the topic of using Advanced Oxidation Processes (AOP) to remove selected pollutants from the water matrix via food dye Brilliant Blue E133 removal. For the AOPs reactions systems 3 types were chosen: UV/H2O2, UV/TiO2 and UV/H2O2/TiO2 system. Although the AOP reactor prototype has been constructed only for the TiO2 system, there has been proven efficiency for the two remaining systems. All three of these systems exhibited dye degradation level from 63,29 ± 9,97 % for UV/TiO2 system to 77,06 ± 2,23 % for UV/H2O2 system in 240 minutes long experiments. This thesis offers complex and up to date view regarding AOP issue in wider context and demonstrates its usefulness in half controlled conditions.
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Hydrolytical stability of poly(3-hydroxybutyrate)
Korčušková, Martina ; Petruš, Josef (referee) ; Kučera, František (advisor)
The bachelor thesis deals with the study of hydrolytical stability of poly(3-hydroxybutyrate) in the hydrolysis with excess of water and in the hydrolytic degradation in melt. Theoretical part summarises knowledge about the process, mechanism and kinetics of hydrolysis and contains an overview of further decomposition reactions of poly(3-hydroxybutyrate). Experimental part is focused on degradation of poly(3-hydroxybutyrate) in the presence of water and on comparing the rate of hydrolytical degradation with acidic and alkaline catalysis. In order to comparing the range of hydrolysis, hydrolytic degradation of poly(3-hydroxybutyrate) was investigated in extruder at the temperature of 170 °C. Samples were analyzed to determine the melt volume index, melt temperature, degree of crystallinity, distribution of molecular mass and the structure of poly(3 hydroxybutyrate) using infrared spectroscopy.
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Functionalization of polyolefins by grafting
Paulenka, Igor ; Petruš, Josef (referee) ; Petrůj, Jaroslav (advisor)
The theoretical part of the diploma thesis is focused on the funcionalization of polyolefins in order to accelerate their degradation and to increase their carbon content from renewable resources with focus on hydroxyacids. The experimental part is focused on preparing samples and studying the properties of the polypropylene and polyethylene blends with the polylactide with different contents of the initiator and the maleic anhydride. Samples were evaluated by determining the degree of conversion maleic anhydride, differential scanning calorimetry, infrared spectroscopy, melt flow index and mechanical properties.
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Effect of enzymes on the degradation of thermosensitive copolymers for controlled release of drugs
Dávidíková, Anna Mária ; Michlovská, Lenka (referee) ; Vojtová, Lucy (advisor)
Termocitlivé hydrogély, ktoré sa používajú ako nosiče liečiv v dnešnej dobe zažívajú obrovský záujem v spoločnosti. Používajú sa ako spôsob dopravy liečiva na predom určené miesto a po dosiahnutí určeného miesta slúžia ako dlhodobé úložisko liečiv v tele. Vlastnosti hydrogélov môžu byť upravované tak, aby dokázali naviazať rôzne druhy liečiv, aby boli citlivé na rôzne vonkajšie impulzy a aby degradovali pomalšie, čo predĺži životnosť liečiv v tele. Aby sme vedeli, ako upraviť vlastnosti hydrogélov a ako sa budú správať, musíme poznať ich degradačný proces a chovanie v rôznych degradačných médiách. Práve preto sú degradačné štúdie veľmi dôležitou súčasťou štúdií hydrogélov. Táto bakalárska práca je zameraná na sledovanie degradácie rôznych roztokov termocitlivého hydrogélu vo viacerých degradačných médiách. Teoretická časť práce zahrňuje krátky prehľad o tom, čo sú to termocitlivé hydrogély, ich charakterizácia a popis vlastností spolu s použitím hydrogélov ako nosičov liečiv. Ďalej sa teoretická časť venuje degradácií hydrogélov celkovo ako aj degradácií konkrétne použitého hydrogélu v tejto bakalárskej práci. V prvom rade bol syntetizovaný živou polymeráciou za otváraním kruhu v inertnej atmosfére termocitlivý PLGA-PEG-PLGA kopolymér, tvorený poly(mliečnou-co-glykolovou kyselinou)-b-poly(ethylen glykolom)-b-poly(mliečnou-co-glykolovou kyselinou). Následne bol kopolymér charakterizovaný na protónovej nukleárnej magnetickej rezonancii a na gélovej chromatografii. Z nasyntetizovaného kopolyméru boli pripravené tri vodné roztoky hydrogélu o rôznych koncentráciách a to 10, 15 a 20 hm %. Vzorky pripravených hydrogélov za teploty 37 , boli degradované v rôznych degradačných roztokoch (UPW (ultra čistá voda), NaCl, PBS (fosfátový pufr) a roztok PBS s enzýmom). Degradačná štúdia bola hlavným cieľom tejto bakalárskej práce. Jednotlivé vzorky boli odobrané v konkrétne stanovené časy a to po 1, 2, 3, 7, 9, 14, 16, 21, 23 a 30 dňoch. Pri vzorkách s enzýmom bola predpokladaná rýchlejšia degradácia vzoriek, tak tieto odbery boli nastavené po 1, 2 a 3 dňoch. Ďalším cieľom tejto práce bola analýza odobraných vzoriek hydrogélov po degradácií na gélovej chromatografii a analýza degradačných médií na kvapalinovej chromatografií s hmotnostným spektrometrom. Počas degradácie vzoriek bola prevedená taktiež gravimetrická analýza a pri odoberaní degradačných roztokov bolo merané ich pH. Následne boli všetky získané dáta vyhodnotené a bolo sledované, či enzým urýchľuje PLGA-PEG-PLGA hydrolytickú degradačnú kinetiku. Výsledky poukazujú na to, že enzým má nízky vplyv na rýchlosť degradácie. Výsledky tejto práce poslúžia ako základy pre budúce degradačné štúdie.
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Analysis of Nicotine or Opium Alkaloids in Historical Pharmaceutical Relics from 18th Century
Belianský, Michal ; Nesměrák, Karel (advisor) ; Kubíčková, Anna (referee)
Belianský M.: Analysis of Nicotine or Opium Alkaloids in Historical Pharmaceutical Relics from 18th Century. Bachelor Thesis. Prague, Charles University, Faculty of Science 2020. Abstract: Two samples of historical relics of pharmaceuticals dated to the 18th century were analyzed; the first sample contained tobacco, the second laudanum, i.e., a preparation containing opium. HPLC with UV or mass detection was used for analysis. Separation of the alkaloids was performed on X Bridge® BEH C18 column using binary gradient elution. By comparison with a modern tobacco sample and on the basis of data from the literature, the presence of nicotine degradation products, especially 6-hydroxy-N-methylmyosmine, was found in the historical sample. Because the nicotine content in the historical sample was very low, it was not possible to quantify it. The analysis of opium analytes in the second historical relics revealed the main opium alkaloids (cotarnine, morphine, meconin, papaverine, and noscapine) as well as their degradation products. Main alkaloids were also quantified. The ratio of noscapine to cotarnine was determined, which according to the literature is an indicator of the age of opium pharmaceuticals. Key words: degradation, HPLC, mass spectrometry, nicotine alkaloids, opium alkaloids
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Use of Advanced Oxidation Processes to remove selected pollutants from the water matrix
Minich, Marek ; Landová, Pavlína (referee) ; Repková, Martina (advisor)
This bachelor’s thesis deals with the topic of using Advanced Oxidation Processes (AOP) to remove selected pollutants from the water matrix via food dye Brilliant Blue E133 removal. For the AOPs reactions systems 3 types were chosen: UV/H2O2, UV/TiO2 and UV/H2O2/TiO2 system. Although the AOP reactor prototype has been constructed only for the TiO2 system, there has been proven efficiency for the two remaining systems. All three of these systems exhibited dye degradation level from 63,29 ± 9,97 % for UV/TiO2 system to 77,06 ± 2,23 % for UV/H2O2 system in 240 minutes long experiments. This thesis offers complex and up to date view regarding AOP issue in wider context and demonstrates its usefulness in half controlled conditions.
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Hydrolytical stability of poly(3-hydroxybutyrate)
Korčušková, Martina ; Petruš, Josef (referee) ; Kučera, František (advisor)
The bachelor thesis deals with the study of hydrolytical stability of poly(3-hydroxybutyrate) in the hydrolysis with excess of water and in the hydrolytic degradation in melt. Theoretical part summarises knowledge about the process, mechanism and kinetics of hydrolysis and contains an overview of further decomposition reactions of poly(3-hydroxybutyrate). Experimental part is focused on degradation of poly(3-hydroxybutyrate) in the presence of water and on comparing the rate of hydrolytical degradation with acidic and alkaline catalysis. In order to comparing the range of hydrolysis, hydrolytic degradation of poly(3-hydroxybutyrate) was investigated in extruder at the temperature of 170 °C. Samples were analyzed to determine the melt volume index, melt temperature, degree of crystallinity, distribution of molecular mass and the structure of poly(3 hydroxybutyrate) using infrared spectroscopy.
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