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• Efficiency Analysis of Solar Facilities for Building Heating and Household Water Heating under Conditions in the Czech Republic

  Michal Pivko, Simona Jursová, Juraj Turjak

  The paper studies the efficiency of solar facilities applied for the heating of buildings and household water heating in the Czech Republic. The Czech Republic is situated in the temperate zone characterized by changeable weather. It is respected in the assessment of a solar facility installation. The efficiency of solar facilities is evaluated according to energy and economic balances. It is analyzed for solar facilities heating both household water and buildings. The main problems relating to the implementation of solar facilities and their operation in the temperate zone with hot summer and freezing winter are discussed.

• Experiments on Rocks under High Pressure Conditions in GTA 20-32 Triaxial Press

  Josef Poláček, Alena Kožušníková

  The paper describes the methodology of measurements in the GTA 20-32 triaxial press. The deformation behaviour of two different types of rocks was compared: • gypsum with plastic deformation even at lower confining pressure, • Carboniferous sandstone with brittle failure even at the highest confining pressure. The influence of gypsum layering was studied as well. The experimental results show that the deformation and strength properties of the gypsum in the triaxial state of stress do not significantly depend on the orientation of axial stress to the observed layering.

• Coal Market of Ukraine: Analysis and Development Background

  Ilona V. Kochura

  The article analyses factors influencing the Ukrainian coal market. Based on the analysis the preconditions of further development of coal industry in Ukraine are formulated.

• Remote Sensing Methods in the Identification of Oil Contaminations

  Eva Smejkalová, Petr Bujok

  The article deals with the possibilities of using remote sensing methods for analysis, observation and identification of old ecological hazards caused by petroleum contaminations from insufficiently plugged and abandoned oil wells in the area of Hodonín. It is focused on the description and determination of areas of interests, remote sensing approaches to the problems of petroleum substance detection and establishing the methodology of an acquired data analysis. Moreover, proper methods, algorithms and satellite digital data parameters for this aim are discussed. The article also describes in-situ measurements, technical instruments and further research advancements. Finally, the proposals of the results evaluation, interpretation and complex comparisons with the results of past and future researches in the area of Nesyt - Hodonín are specified.

• Influence of Reaction Medium on CO₂ Photocatalytic Reduction Yields over

  Martin Reli, Marcel Šihor, Kamila Kočí, Petr Praus, Ondřej Kozák, Lucie Obalová

  The reduction of CO₂ by photocatalysts is one of the most promising methods since CO₂ can be reduced to useful compounds by irradiating it with UV light at room temperature and ambient pressure. The aim of this work was to assess the effect of a reaction media on CO₂ photocatalytic reduction yields over ZnS nanoparticles deposited on montmorillonite (ZnS-MMT). Four different reaction media, such as NaOH, NaOH+Na₂SO₃ (1:1), NH₄OH, NH₄OH+Na₂SO₃ (1:1), were tested. The pure sodium hydroxide was better than ammonium hydroxide for the yields of the both gas phase (CH₄ and CO) and liquid phase (CH₃OH). The addition of Na₂SO₃ improved methanol yields due to the oxidation prevention of incipient methanol to carbon dioxide. The gas phase yields were decreased by the Na₂SO₃ addition. The best tested reaction medium for the photocatalytic reduction of CO₂ was the solution of sodium hydroxide.