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Graphene and graphite oxide reinforced magnesium oxychloride cement (MOC) pastes were researched. To produce MOC pastes, the light-burnt magnesium oxide was added and dispersed in the magnesium chloride solution. The graphene powder, graphite oxide powder, and their combination were incorporated in the solution. The total amount of the nano additives was 0.5% by the weight of the magnesium oxychloride binder. The morphology and microstructure of the hardened materials were studied using scanning electron microscopy (SEM). The phase composition of precipitated MOC-based products was investigated using X ray diffraction (XRD). The macrostructural parameters of the composites such as bulk density, specific density, and open porosity were evaluated. Mechanical strength and stiffness were analyzed by the measurement of flexural and compressive strength and dynamic elastic modulus. The electrical properties were examined by the use of impedance spectroscopy (IS). From the experimental results the model of the transport of electric charge in researched materials dispersion was estimated. The use of graphene- and graphite oxide-reinforcement of MOC matrix gave highly dense materials of low porosity, high mechanical resistance, whereas the used nano-additives enabled the produce of composites of high strength efficiency index. The addition of graphene particles and the formation of graphite agglomerates significantly decreased electrical resistivity of the MOC matrix which was originally characterized by low electrical conductivity.

In this paper, we demonstrated that wooden chips ash can be further processed and selected products of its treatment can be used as additives in magnesium phosphate cement composites. Wooden chips ash, as well as obtained products, were analysed by XRF, XRD, SEM, EDS, STA. Also, the particle size of the obtained fractions was analysed using laser diffraction. Basic structural properties, bulk density, specific density, total open porosity and pore size distribution of prepared composite material in comparison to the reference were measured. In addition, mechanical properties were also tested. The newly developed composite with incorporated fractions of wood chips ash showed acceptable structural and mechanical properties that were almost unchanged compared to the reference sample without any biomass-based additives.

The present article describes trends in the development of the journalistic profession as seen by Swedish and Russian students in journalism. The study focuses on the results of a survey carried out among students at three Swedish and three Russian institutions of higher education. The survey demonstrates numerous similarities in ideals and values as well as in understanding of the professional code of journalism among students in Russia and Sweden. Historical background is evident in the students’ different interpretations of key problems of journalism and in their assessment of freedom of the press. Finally, the research questions the professional future of journalism, focusing on possible threats and presenting several development scenarios for the industry.

The effect of high temperature exposure on properties of a newly designed High Performance Concrete (HPC) is studied in the paper. The HPC samples are exposed to the temperatures of 200, 400, 600, 800, and 1000°C respectively. Among the basic physical properties, bulk density, matrix density and total open porosity are measured. The mechanical resistivity against disruptive temperature action is characterised by compressive strength, flexural strength and dynamic modulus of elasticity. To study the chemical and physical processes in HPC during its high-temperature exposure, Simultaneous Thermal Analysis (STA) is performed. Linear thermal expansion coefficient is determined as function of temperature using thermodilatometry (TDA). In order to describe the changes in microstructure of HPC induced by high temperature loading, MIP measurement of pore size distribution is done. Increase of the total open porosity and connected decrease of the mechanical parameters for temperatures higher than 200 °C were identified.