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The authors present their own model applicable for effective desulphurization of steel by ladle treatment. The model is based on a thermodynamic approach (equilibrium data) and technological data (correction factors). It consists of two parts. In the first part the authors present the formulae derived for estimation of the additions of deoxidation agents which ensure sufficiently low oxygen level prior to the desulphurization process, while the other part gives a qualitative and quantitative selection of slag formers to achieve low final levels of sulphur in steel. For the deoxidation process two variants were considered: (i) with Al only (for low silicon steels) or (ii) Al‐Si (for silicon steels) as deoxidizers. For the desulphurization process three variants were assumed as to ladle slag composition: (i) slag consisting of a fraction of furnace slag, lime addition and deoxidation products, (ii) slag made of synthetic CaO–Al2O3 and (iii) slag based on lime and fluorspar. The model formulae for desulphurization were derived using the sulphide capacity concept which relies on the optical basicity. In addition, rough estimates of the slag liquidus temperatures are given. A numeric example of the model application and the model algorithm (appendix) are enclosed.

Mining industry is one of the most important customers of electric motors. The most commonly used in the contemporary mining industry is alternating current machines used for processing electrical energy into mechanical energy. The operating problems and the influence of qualitative interference acting on the inputs of individual regulators to field-oriented system in the course of underground mining operations has been presented in the publication. The object of controlling the speed is a slip-ring induction motor. Settings of regulators were calculated using an evolutionary algorithm. Examination of system dynamics was performed by a computer with the use of the MATLAB / Simulink software. According to analyzes, large distortion of input signals of regulators adversely affects the rotational speed that pursued by the control system, which may cause a large vibration of the whole system and, consequently, its much faster destruction. Designed system is characterized by a significantly better resistance to interference. The system is stable with the properly selected settings of regulators, which is particularly important during the operation of machinery used in underground mining.

We investigated the effect of uniaxial pressure (0 ÷ 1000 bars) applied parallely to the ac electric field on dielectric properties of PLZT-x/65/35 (2 x 13) ceramics. There was revealed a significant effect of the external stress on these properties. The application of uniaxial pressure leads to the change of the peak intensity of the electric permittivity (ε), of the frequency dispersion as well as of the dielectric hysteresis. The peak intensity ε becomes diffused/sharpened and shifts to a higher/lower temperatures with increasing the pressure. It was concluded that the application of uniaxial pressure induces similar effects as increasing the Ti ion concentration in PZT system. We interpreted our results based on the domain switching processes under the action of combined electromechanical loading.

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In the article, the aims of teaching bioscience in primary and middle school have been introduced. Core curriculum has been mentioned as well, and the tools that may be used by a teacher to convey theory and practical knowledge in the most efficient way  have been discussed. Furthermore, it has been noticed that various ecological ventures have a positive impact on children's ecological awareness. In the second part of the article, results of surveys conducted among primary and middle school students have been introduced. It embraces also questions and answers, in which children describe their knowledge level about the condition of environment and talk about their attitude towards taking care of nature, and what are the stimuli of such demeanours. In addition, the task of surveys was to find out which issues teachers pay particular attention to. The last two questions were to check the knowledge.

Abstract. The publication presents an assessment of the impact of meteorological conditions on air quality in a given location. The subject matter of the work is related to problem-review issues in the field of environmental protection and energy management. The publication draws attention to the fact that despite several decades of ecological monitoring of air pollution, only in recent years attention has been paid to the scale of air pollution problem. The study examined the relationship between meteorological elements (wind velocity, relative humidity on the amount of air pollution immissions. Significant impact of precipitation, atmospheric pressure and thermal braking layer was indicated. The possibilities of air quality improvement were presented based on the measurement data concerning the immission of impurities.

Abstract. The aim of this study was to determine the effect of regulation of an axis of a wind turbine rotor to the direction of wind on the volume of energy produced by wind turbines. A role of an optimal setting of the blades of the wind turbine rotor was specified, as well. According to the measurements, changes in the tilt angle of the axis of the wind turbine rotor in relation to the air stream flow direction cause changes in the use of wind energy. The publication explores the effects of the operating conditions of wind turbines on the possibility of using wind energy. A range of factors affect the operation of the wind turbine, and thus the volume of energy produced by the plant. The impact of design parameters of wind power plant, climatic factors or associated with the location seismic challenges can be shown from among them. One of the parameters has proved to be change settings of the rotor axis in relation to direction of flow of the air stream. Studies have shown that the accurate determination of the optimum angle of the axis of the rotor with respect to flow of air stream strongly influences the characteristics of the wind turbine.