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Utilization of by-pass cement kiln dust in alkali activated materials
Kiripolský, Tomáš ; Beranová, Denisa (referee) ; Kalina, Lukáš (advisor)
By-pass cement kiln dust (CKD) is a fine grained by-product of Portland clinker manufacturing. Its chemical composition is not suitable for the returning back into the feedstock and therefore has to be discharged. Such the increasing waste production contributes to lowering of the environmental impact of cement industry. The possible solution for the ecological processing of CKD is its incorporation into alkali activated blast furnace slag binders. Thanks to the high alkaline content, CKD serves as an effective accelerator for the latent hydraulic substance and at the same time solves the significant shrinkage of alkali activated materials which considerably limiting their practical applications. It was found out that the suitable amount of CKD (20 % replacement of slag) in combination with sodium carbonate increases the compressive strength development of about 10 % and reduces the drying shrinkage (11 % reduction). On the other hand this type of inorganic admixture accelerated the hydration process resulting in rapid loss of workability and shortening the initial setting time. The mechanism of action of CKD in alkali activated matrix has been investigated as well as its optimal dosage in the means of mechanical properties.
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Utilization of by-pass cement kiln dust in alkali activated materials
Kiripolský, Tomáš ; Beranová, Denisa (referee) ; Kalina, Lukáš (advisor)
By-pass cement kiln dust (CKD) is a fine grained by-product of Portland clinker manufacturing. Its chemical composition is not suitable for the returning back into the feedstock and therefore has to be discharged. Such the increasing waste production contributes to lowering of the environmental impact of cement industry. The possible solution for the ecological processing of CKD is its incorporation into alkali activated blast furnace slag binders. Thanks to the high alkaline content, CKD serves as an effective accelerator for the latent hydraulic substance and at the same time solves the significant shrinkage of alkali activated materials which considerably limiting their practical applications. It was found out that the suitable amount of CKD (20 % replacement of slag) in combination with sodium carbonate increases the compressive strength development of about 10 % and reduces the drying shrinkage (11 % reduction). On the other hand this type of inorganic admixture accelerated the hydration process resulting in rapid loss of workability and shortening the initial setting time. The mechanism of action of CKD in alkali activated matrix has been investigated as well as its optimal dosage in the means of mechanical properties.
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Computational Study of the Properties and Reactivity of Bioinroganic Transition Metal Complexes
Baxová, Katarína ; Burda, Jaroslav (advisor) ; Sochorová Vokáčová, Zuzana (referee)
This work is focused on the reactions of diaqua-tetrakis(μ-acetylato)dirhodium(II,II) with guanine, that shows anti-cancer activities. Guanine can bond to the complex either by oxygen O6 or by nitrogen N7. We studied three possible versions of the system - one that is protonated on guanine, one protonated on the paddle-wheel and a neutral one. For all 6 reactions transition structures were found. For reactants, tranzition states and products we computed the values of electron density in the critical points of bonds, partial atom charges and the interaction energies of the system, guanine and water on the b3lyp/aug-cc- pvdz level. Pseudobasis and pseudopotentials were employed in the case of rhodium atom. For all the reactions thermodynamical properties were computed. Powered by TCPDF (www.tcpdf.org)
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