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Specification of the phase composition of Portland clinker
Vávrová, Alžběta ; Dlabajová, Lucie (referee) ; Másilko, Jiří (advisor)
This bachelor thesis deals with the determination of the phase composition of portland clinker and its optimization. The X-ray fluorescence spectroscopy, X-ray diffraction analysis and optical microscopy were used to solve this task. In the experimental section, X-ray fluorescence spectrometry results were used to calculate the potential phase composition of the clinker using the Bogue method. Then the X-ray diffraction analysis followed, it was used not only to determine the phase composition but also to determine amorphous content in the clinker. The microscope integration method was used to study the samples using optical microscopy. The obtained results were compared with each other and the main deficiencies of the individual methods were identified.
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Options of preparation of tobermorite
Dlabajová, Lucie ; Másilko, Jiří (referee) ; Opravil, Tomáš (advisor)
The bachelor thesis deals with options of preparation of tobermorite. Tobermorite is a mineral, which, thanks to its composition and properties, is an important phase in aerated concrete. On the field of science and research, an attention has been drawn on tobermorite as an ion ex-changer. Synthesis of a pure mineral can cause problems with testing and improving its properties. Tobermorite crystallizes together with other calcium silicate hydrates from system CaO-SiO2-H2O during a hydrothermal reaction. This thesis mainly focuses on influence of choosing starting materials and their treatment before the hydrothermal synthesis. Other influences which are studied are conditions of hydrothermal processes and their influence on final products of hydrothermal synthesis. Phase composition of prepared samples was characterized by XRD and TG-DTA. As an additional analyze was used scanning electron microscopy (SEM).
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Preparation of Tobermorite
Dlabajová, Lucie ; Palou, Martin (referee) ; Martinec, Petr (referee) ; Ptáček, Petr (advisor)
This doctoral thesis is focused on the study of reactions in the CaO–SiO2–H2O complex system, primarily to the synthesis of crystalline tobermorite. Hydrothermal conditions are necessary for the formation of crystalline tobermorite, whereas the course of the reaction is influenced by several factors. The main studied factor was the choice of the silica sources differing in means of solubility, crystallinity, particle size distribution, specific surface area, and purity. The water-to-solid ratio turned to be also an important factor as the length of the hydrothermal reaction. The influence of the mechanochemical pretreatment of starting materials to the final phase composition of samples was studied as well. The obtained results show that the crystallinity of the silica source is the main factor influencing the reaction rate and the purity of the synthesized tobermorite. While using the crystalline silica source the shorter silicate chains are formed and the formation of tobermorite structure is easier. Using the amorphous silica sources and the mechanochemical pretreatement of starting materials prolong the hydrothermal reaction. The prepared samples are always the mixture of crystalline or semicrystalline calcium hydrosilicates instead of the phase pure tobermorite.
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Fabrication of dental glass-ceramics
Hasalíková, Tereza ; Dlabajová, Lucie (referee) ; Bartoníčková, Eva (advisor)
This bachelor´s thesis deals with the study of glass-ceramic materials and their use in dentistry. Nowadays, studies are placed on health harmless of the material, the biological ability to adapt to the host tissue, mechanical properties, affordability, easy and fast production, aesthetics and quick recovery of the patient. The theoretical part of the work deals with various materials from various input materials used for dental substitutes. Special attention is paid to glass-ceramic and ceramic biomaterials, their preparation, heat treatment and health testing. The experimental part deals with the preparation of powder materials by the sol-gel method. Of the larger number of samples, those were selected for gelation and showed good XRD and heat microscopy results. The selected samples were subsequently subjected to heat treatment to form a glass ceramic material. The products were characterized by XRD phase composition in terms of phase temperature behavior by TG-DTA analysis, heat microscopy and SEM morphology analysis of prepared particle.
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Alumina based refractories for noncement application
Böhm, Petr ; Dlabajová, Lucie (referee) ; Švec, Jiří (advisor)
The thesis deals with the possibility of bonding the ceramic mixture by a sol-gel method, Colloidal alumina was used as the sol and the gelation was performed by changing the ionic strength or pH. The influence of different gelling agents (NaCl, NH4Cl, NH3, MgO a CO(NH)) on the gellation time and on the course of the gelation was compared. The aim of the work is the preparation of refractory monolith with the highest packing desity possible, which was solved by modeling the granulometric curve of the solid part of the ceramic mixture based on alumina. The thesis also describes the behavior of prepared gels during thermal processing of ceramics. Subsequently the resulting structure of prepared ceramic bodies was monitored.
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Preparation of Tobermorite
Dlabajová, Lucie ; Palou, Martin (referee) ; Martinec, Petr (referee) ; Ptáček, Petr (advisor)
This doctoral thesis is focused on the study of reactions in the CaO–SiO2–H2O complex system, primarily to the synthesis of crystalline tobermorite. Hydrothermal conditions are necessary for the formation of crystalline tobermorite, whereas the course of the reaction is influenced by several factors. The main studied factor was the choice of the silica sources differing in means of solubility, crystallinity, particle size distribution, specific surface area, and purity. The water-to-solid ratio turned to be also an important factor as the length of the hydrothermal reaction. The influence of the mechanochemical pretreatment of starting materials to the final phase composition of samples was studied as well. The obtained results show that the crystallinity of the silica source is the main factor influencing the reaction rate and the purity of the synthesized tobermorite. While using the crystalline silica source the shorter silicate chains are formed and the formation of tobermorite structure is easier. Using the amorphous silica sources and the mechanochemical pretreatement of starting materials prolong the hydrothermal reaction. The prepared samples are always the mixture of crystalline or semicrystalline calcium hydrosilicates instead of the phase pure tobermorite.
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|
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Alumina based refractories for noncement application
Böhm, Petr ; Dlabajová, Lucie (referee) ; Švec, Jiří (advisor)
The thesis deals with the possibility of bonding the ceramic mixture by a sol-gel method, Colloidal alumina was used as the sol and the gelation was performed by changing the ionic strength or pH. The influence of different gelling agents (NaCl, NH4Cl, NH3, MgO a CO(NH)) on the gellation time and on the course of the gelation was compared. The aim of the work is the preparation of refractory monolith with the highest packing desity possible, which was solved by modeling the granulometric curve of the solid part of the ceramic mixture based on alumina. The thesis also describes the behavior of prepared gels during thermal processing of ceramics. Subsequently the resulting structure of prepared ceramic bodies was monitored.
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Fabrication of dental glass-ceramics
Hasalíková, Tereza ; Dlabajová, Lucie (referee) ; Bartoníčková, Eva (advisor)
This bachelor´s thesis deals with the study of glass-ceramic materials and their use in dentistry. Nowadays, studies are placed on health harmless of the material, the biological ability to adapt to the host tissue, mechanical properties, affordability, easy and fast production, aesthetics and quick recovery of the patient. The theoretical part of the work deals with various materials from various input materials used for dental substitutes. Special attention is paid to glass-ceramic and ceramic biomaterials, their preparation, heat treatment and health testing. The experimental part deals with the preparation of powder materials by the sol-gel method. Of the larger number of samples, those were selected for gelation and showed good XRD and heat microscopy results. The selected samples were subsequently subjected to heat treatment to form a glass ceramic material. The products were characterized by XRD phase composition in terms of phase temperature behavior by TG-DTA analysis, heat microscopy and SEM morphology analysis of prepared particle.
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Specification of the phase composition of Portland clinker
Vávrová, Alžběta ; Dlabajová, Lucie (referee) ; Másilko, Jiří (advisor)
This bachelor thesis deals with the determination of the phase composition of portland clinker and its optimization. The X-ray fluorescence spectroscopy, X-ray diffraction analysis and optical microscopy were used to solve this task. In the experimental section, X-ray fluorescence spectrometry results were used to calculate the potential phase composition of the clinker using the Bogue method. Then the X-ray diffraction analysis followed, it was used not only to determine the phase composition but also to determine amorphous content in the clinker. The microscope integration method was used to study the samples using optical microscopy. The obtained results were compared with each other and the main deficiencies of the individual methods were identified.
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|
|
Options of preparation of tobermorite
Dlabajová, Lucie ; Másilko, Jiří (referee) ; Opravil, Tomáš (advisor)
The bachelor thesis deals with options of preparation of tobermorite. Tobermorite is a mineral, which, thanks to its composition and properties, is an important phase in aerated concrete. On the field of science and research, an attention has been drawn on tobermorite as an ion ex-changer. Synthesis of a pure mineral can cause problems with testing and improving its properties. Tobermorite crystallizes together with other calcium silicate hydrates from system CaO-SiO2-H2O during a hydrothermal reaction. This thesis mainly focuses on influence of choosing starting materials and their treatment before the hydrothermal synthesis. Other influences which are studied are conditions of hydrothermal processes and their influence on final products of hydrothermal synthesis. Phase composition of prepared samples was characterized by XRD and TG-DTA. As an additional analyze was used scanning electron microscopy (SEM).
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