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Influence of selected agents on crystallization power of polylactide
Kurakin, Yuriy ; Přikryl, Radek (referee) ; Bálková, Radka (advisor)
The influence of seven additives on the crystallization ability of polylactide (PLA), melt flow index (MVR) and mechanical tensile properties was studied. Pressed plates with a thickness of 0.8 mm were tested. Selected additives added in amounts of 0.5 and 1.0% were as follows: talc, sodium benzoate, mixtures of organic salts with amorphous SiO2 and zinc stearate, metal salt, phosphate salt, and potassium salt of 5-dimethylsulfoisophthalate (LAK-301 - nucleating agent developed for PLA). Non-isothermal crystallization measurements were performed at different cooling rates (0.3; 0.5; 0.7; 1.0 and 1.5 ° C). All nucleation agents increased the MVR of PLA except talc; the largest increase (9-fold and 24-fold) was the addition of metal salt. The additives did not fundamentally change the mechanical properties. All samples were rather brittle (the most brittle with LAK-301), the modulus of elasticity was around 1.2 GPa for all samples, the strength of PLA was increased the most by the addition of 1% talc (by 12%) and the elongation at break was increased by organic salt with SiO2. All samples with nucleating agents content of 1% were amorphous (crystalline content did not exceed 2%). Thus, the addition of reagents did not support the crystallization process during rapid cooling, even in the case of LAK-301. However, LAK-301 was acting as an excellent nucleating agent at slow cooling rates (1.5 °C / min and below). The nucleation activity of the additives decreased in the following order: LAK-301, organic salt with zinc stearate, talc, organic salt modified with amorphous SiO2 and phosphate salt. Samples with sodium benzoate and metal salt were crystallizing on cooling in several steps and it was not possible to use the method of Dobrev and Gutzow to evaluate the nucleation activity.
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The Possibilities of innovation of the sanitary ceramics body
Čech, Tomáš ; Chudomelka, Josef (referee) ; Sokolář, Radomír (advisor)
The aim of this thesis is to assess the possibility of increasing utility properties shard of sanitary ceramics. Description the current production of sanitary ceramics. Assessing of the impact steatite admixture into existing raw material mixture for the production of sanitary ceramics firing body characteristics (porosity, strength, thermal expansion) using the available scientific literature. Proposition the optimal dose of steatite material into the raw mixture. Evaluation of physical and mechanical properties of the resulting products of this recipe.
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Meta-talc Application in Inorganic Materials
Bednárek, Jan ; Rovnaník, Pavel (referee) ; Palou, Martin (referee) ; Havlica, Jaromír (advisor)
This thesis is focused at possibilities of preparation and characterization of XRD-amorphous delaminated and dehydroxylated talc phase – meta-talc, which can have its potential application and a starter material for a preparation of magnesium-silicate analogues of geopolymers. Changes in structure and morphology of talc ore were observed during this work. For the purposes of this research, two various talc ores – chloritic and dolomitic were examined. Whole process of meta-talc preparation was examined with whole scale of instrumental techniques such as X-ray diffraction, simultaneous thermogravimetric a differential thermal analysis, infrared spectroscopy, scanning electron microscopy or laser analysis of particle size. Meta-talc can be obtained via mechanochemical activation of talc ore with subsequent calcination. Mechanochemical treatment lead to destruction of original crystal structure and breaking of original bonds, i.e. the product of this treatment was almost amorphous and delaminated. Most of hydroxyl groups were converted to molecules of water which remained adsorbed or coordinated in ore structure. These molecules were removed during calcination step.
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Possibilities of application of meta-talc
Fridrich, Jakub ; Ptáček, Petr (referee) ; Opravil, Tomáš (advisor)
The aim of this bachelor thesis is study of physical and chemical properties of metatalk. Metatalc is delaminated and dehydroxylated form of talc which was earlier prepared and described on FCH BUT in cooperation with MRC (Material Research Center). This thesis is part of the way to find suiting use for this newly found material and it takes on proposing forms of use. Tested attributes are particle size, particle surface, volumetric mass, sorption and cation exchange capacity.
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SStudy of crystalline structure of polyhydroxybutyrate and nucleating activity of selected additives
Sedláček, Zbyněk ; Tocháček, Jiří (referee) ; Bálková, Radka (advisor)
This diploma thesis deals with study of crystalline structure of polyhydroxybutyrate (PHB), which contains different types of additives for studying of their nucleation activity and which were prepared by mixing. It is about boronitrid (BN), sacharin, hydroxapatit, plasticizer Tegmer a tree types of talc. Crystal structure was analysed by differential scanning calorimetry and x-ray diffraction, supramolecular structure was observed by optical microscopy (polarized and confocal laser scanning). Nucleating activity was evaluated by isothermal and non-isothermal crystallization made on calorimeter and heated table of optical microscope. There is not influence of additives on crystallographic structure, but additives affects number and size of spherulites including crystal domains defects, which can have impact on final mechanical properties. BN and talcs react as nucleating agents, other additives during low and high cooling speeds (vc) inhibit nucleation and in middle cooling speeds are without effect. Nucleating activity is not evaluated by numerically, because decrease of crystallization temperature together with vc is not linear. Results of direct methods are based on picture analysis, which is great benefit for understanding of crystal behaviour of PHB.
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Influence of selected agents on crystallization power of polylactide
Kurakin, Yuriy ; Přikryl, Radek (referee) ; Bálková, Radka (advisor)
The influence of seven additives on the crystallization ability of polylactide (PLA), melt flow index (MVR) and mechanical tensile properties was studied. Pressed plates with a thickness of 0.8 mm were tested. Selected additives added in amounts of 0.5 and 1.0% were as follows: talc, sodium benzoate, mixtures of organic salts with amorphous SiO2 and zinc stearate, metal salt, phosphate salt, and potassium salt of 5-dimethylsulfoisophthalate (LAK-301 - nucleating agent developed for PLA). Non-isothermal crystallization measurements were performed at different cooling rates (0.3; 0.5; 0.7; 1.0 and 1.5 ° C). All nucleation agents increased the MVR of PLA except talc; the largest increase (9-fold and 24-fold) was the addition of metal salt. The additives did not fundamentally change the mechanical properties. All samples were rather brittle (the most brittle with LAK-301), the modulus of elasticity was around 1.2 GPa for all samples, the strength of PLA was increased the most by the addition of 1% talc (by 12%) and the elongation at break was increased by organic salt with SiO2. All samples with nucleating agents content of 1% were amorphous (crystalline content did not exceed 2%). Thus, the addition of reagents did not support the crystallization process during rapid cooling, even in the case of LAK-301. However, LAK-301 was acting as an excellent nucleating agent at slow cooling rates (1.5 °C / min and below). The nucleation activity of the additives decreased in the following order: LAK-301, organic salt with zinc stearate, talc, organic salt modified with amorphous SiO2 and phosphate salt. Samples with sodium benzoate and metal salt were crystallizing on cooling in several steps and it was not possible to use the method of Dobrev and Gutzow to evaluate the nucleation activity.
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Meta-talc Application in Inorganic Materials
Bednárek, Jan ; Rovnaník, Pavel (referee) ; Palou, Martin (referee) ; Havlica, Jaromír (advisor)
This thesis is focused at possibilities of preparation and characterization of XRD-amorphous delaminated and dehydroxylated talc phase – meta-talc, which can have its potential application and a starter material for a preparation of magnesium-silicate analogues of geopolymers. Changes in structure and morphology of talc ore were observed during this work. For the purposes of this research, two various talc ores – chloritic and dolomitic were examined. Whole process of meta-talc preparation was examined with whole scale of instrumental techniques such as X-ray diffraction, simultaneous thermogravimetric a differential thermal analysis, infrared spectroscopy, scanning electron microscopy or laser analysis of particle size. Meta-talc can be obtained via mechanochemical activation of talc ore with subsequent calcination. Mechanochemical treatment lead to destruction of original crystal structure and breaking of original bonds, i.e. the product of this treatment was almost amorphous and delaminated. Most of hydroxyl groups were converted to molecules of water which remained adsorbed or coordinated in ore structure. These molecules were removed during calcination step.
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Possibilities of application of meta-talc
Fridrich, Jakub ; Ptáček, Petr (referee) ; Opravil, Tomáš (advisor)
The aim of this bachelor thesis is study of physical and chemical properties of metatalk. Metatalc is delaminated and dehydroxylated form of talc which was earlier prepared and described on FCH BUT in cooperation with MRC (Material Research Center). This thesis is part of the way to find suiting use for this newly found material and it takes on proposing forms of use. Tested attributes are particle size, particle surface, volumetric mass, sorption and cation exchange capacity.
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Tourism destination development - Bedřichov in Jizera Mountains
Němeček, Petr ; Fialová, Dana (advisor) ; Kubín, Ewa (referee)
The goal of this thesis is to evaluate the current state of Bedřichov from the perspective of tourism and draw the attention to the threats and opportunities stemming from its potential further development. This thesis employs the Tourism Area Life Cycle (TALC) model, firstly applied to Bedřichov itself and later compared to Špindlerův Mlýn. This method allows for the analysis of the current position of Bedřichov in its life cycle as well as its expected development. The outcome of this thesis should be beneficial in the evaluation of further development in Bedřichov with respect to the ecological sustainability in the region.
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Nursing care management of patients after intrapleural chemical pleurodesis
KIESEWETTEROVÁ, Renáta
The pleurodesis is a treatment method for patients suffered from the symptomatic malignant pleural effusion. The goal of the pleurodesis is to close a pleural area by connection of visceral and parietal pleura in order to reduce or terminate production of pleural effusion. The sterile talc powder is the world's most used agens within a practice. After a parental analgesic is the powder (as a sllury) either applicated into a pleural cavity through the chest drainage or surgically dispersed over the treated (via abrasion, decortication) pleural space during the thoracoscopy/thoracotomy. This diploma thesis focuses on the treatment technique of bedside talc-pleurodesis through the chest drainage. The nurse has an irreplaceable role in the whole process from a preparation of patient to assistance by intrapreural application, to care of patient after the operation or serves as a physical support during potential complications. The aim of the presented work is to detect priorities in nursing care and find out whether patients need increased care after intrapleural therapy. The qualitative research method was chosen for the analysis where semi-structural interview with open questions were used. We created case reports analysed with the adaptive model of Callista Roy as well. The research sample contained patients chosen with respect to specialization of researched problem. We set two basic focal stimuli according to the analysis of respondents´ reactions. These stimuli serve as a basis for determination of priority parts of the nursing care by patients after bedside pleurodesis. We defined the need to be without pain and the need to ensure safety and certainty as a central focus of the nursing care. Among secondary fields of nursing care were identified sleep disturbances and limited mobility, which leads to reduction of self-care in getting dress, hygiene as well as in defection and miction. We found out within the second goal identical intensity of the nursing care before and after bedside talc-pleurodesis. This statement is based on comparison of interventions before and after aplication analysed via adaptive model by Roy. Nevertheless, causes of interventions were modified to a certain extent. The main goal of diploma thesis was to map requirements for high-quality nursing care related to bedside talc-pleurodesis via chest drainage. The work should extend theoretical basis not only for nurses in clinical practice.
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