In cities with large educational institutions, the inflow of educational migrants is important for con-sumption demand, and can trigger multiplier effects. The main aim of this article is to show the mecha-nism of the aggregate demand-income effect created by educational migration in the Polish city of Opole. An estimate of this effect is provided, based on questionnaire research among a sample of 1 075 students from all institutions of higher education located in the city. The estimated effects analysed concern the direct consumption impulse, as well as the indirect job creation and increase in income for providers of accommodation for students, in turn triggering increased consumption demand. While the results must be interpreted with care, an estimated 15 per cent of consumption demand created through expenditure of migrant students (about PLN 175 400 000) and 485 extra job show the significance of such expenditure for the local economy.
Greenhouse gases such as carbon dioxide and water vapour can be captured from gas streams on a zeolite 13X adsorbent. Experimental water vapour adsorption isotherms and kinetic curves were measured in the temperature range of 293–393 K and pressure up to 2100 Pa. The equilibrium data were developed with Toth and Sips multi-temperature isotherm models. The results of the process rate studies were described using pseudo-first and pseudo-second order kinetic models. Findings were compared with our own results of CO2 adsorption studies on the same zeolite.
The article presents a new approach to testing the strength of asphalt interlayer bonding. Two loading methods were used: static load and cyclic load. Before carrying out static shear strength tests, the interlayer bonding was subjected to cyclic loads with a constant number of cycles but with different frequencies. A number of layered samples with and without geosynthetic interlayers were tested at the set temperature. The comparative analyses allowed to determine the functions approximating the impact of the cyclic load frequency on the static strength of bonding at selected interlayer contact conditions. It was also possible to indicate the frequency of cyclic load at which this parameter has the largest and smallest impact on the static strength of the asphalt interlayer bonding.
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