National Repository of Grey Literature 3 records found  Search took 0.00 seconds. 
Volumetric and electrostatic properties of water and their application to aqueous thermodynamics and mineral solubility at high temperatures and pressures
Hanková, Barbora ; Dolejš, David (advisor) ; Zachariáš, Jiří (referee)
Hydrothermal fluids are important mass and heat transfer agents in the Earth's crust and mantle. Aside from their transport role, the aqueous fluids act as reactants or products in rock environment during diverse processes ranging from partial melting, magmatic and metamorphic devolatilization. This study evaluates the effect of equations of state and thermodynamic data for aqueous species on prediction of mineral solubility in aqueous fluids at high temperatures and pressures employing the Helgeson-Kirkham-Flowers model (HKF). These calculations require: (i) volumetric properties of water; (ii) dielectric properties of water; (iii) aqueous species thermodynamic properties. A comparison of ten equations of state against the IAPWS scientific standard reveals that volumetric properties of water up to 1200 řC and 50 kbar are predicted within 5 %, except at low pressure (below 2 kbar), temperatures higher than 1000 řC, and the liquid-vapor equilibrium curve, particularly in the proximity of the critical point of water. The deviations of volumetric and electrostatic properties of water propagate into the mineral solubility calculations. For quartz and corundum these deviations lead to discrepancy in mineral solubility of up to half an order of magnitude for molal concentrations. These discrepancies...
Causes of conflict in Africa. The case of the Democratic Republic of Congo
Hanková, Barbora ; Werkman, Kateřina (advisor) ; Ditrych, Ondřej (referee)
This thesis aims to explore selected theoretical approaches investigating the causes of conflicts on the African continent and then try to apply it to the particular case of the Democratic Republic of Congo and its second war, running from 1998-2003, and then assess the impact of each selected causes of this particular Congolese conflict. This Work in the first chapters outlines the chosen theories related to the causes of armed conflicts in Africa, focusing on three selected causes of conflict: natural resources, ethnicity and weak state. These chapters are theoretical basis for the analysis found in the final chapter. It then evaluates the impact of chosen variables on the outbreak of the Congolese war. Based on the analysis the author draws the following conclusions: 1st the main cause of the second war in the DRC, running in the years 1998 - 2003, can be considered as raw materials, or the efforts of rebel groups and neighboring countries to control and subsequent illegal mining of mineral wealth of The Congo; 2nd although ethnic factors are not the main cause of the second Congolese war, their impact on the conflict, especially in the early days of the conflict is obvious; 3rd nature of the State, namely the weakness of the Government of DRC, ranked according to key indicators, turns out to be the most...

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