Pyrite is a sulfide mineral and is widely distributed in nature. Pyrite may transform into pyrrhotite when heated at high temperatures. In order to support processing engineering techniques and industrial applications of pyrite and pyrrhotite, it is necessary to investigate synthetic pyrrhotite, which is formed by heating pyrite in air, based on existing research. In this work, the mineralogical characteristics and stability conditions of synthetic pyrrhotite formed by heating pyrite at elevated temperatures were studied. The possible formation pathway was verified using a solid-phase reaction. X-ray-diffraction results revealed that synthetic pyrrhotite differs from natural pyrrhotite in the paragenetic association of minerals. Natural pyrrhotite and magnetite coexist in the natural pyrrhotite sample. Synthetic pyrrhotite formed by heating pyrite at 700℃ for 1 h has the paragenetic association with hematite and a small amount of pyrite and magnetite. All pyrrhotite samples were monoclinic pyrrhotite-4C (Fe7S8) and exhibit minimal differences in terms of lattice parameters. Synthetic pyrrhotite-4C was stable under 0.5–2 h of heating at 700℃ in air. It had the highest relative content by heating for 1 h. It was eventually transformed into hematite with heating periods exceeding 3 h, as was the case for pyrite and magnetite. In air, synthetic pyrrhotite-4C is mainly formed via two pathways: (1) pyrite → pyrrhotite-4C and (2) pyrite → magnetite → pyrrhotite-4C. Pathway (1) is more favorable than pathway (2). This transformation cannot be achieved by the reaction between hematite and sulfur.

The aim of the paper is to examine a single case of random substitution which con-sists in the replacement of liquids by glides, that is, gliding. This process occurs in both English and Polish and it affects children’s speech as well as the speech of those adults who did not acquire the proper pronunciation of liquids. We address the following questions: is the substitution really random, why in the majority of cases it results in glides and not in something else, what is the relationship between two articulatorily distant segments which allows them to participate in substitution, among many others. It is argued that some examples of gliding can be analysed as a simple reduction in the elemental make-up of segments, e.g. [] ~ [], others like English [] ~ [] can be the effect of phonetic enhancement sometimes called phonological reinterpretation.

Deposition of aerosols in the respiratory tracts depends on their size distribution. Investigation of such distribution has therefore great meaning lor appropriate assessment o frisk caused by hazardous pollutants that appear in environment both as a result of human activities like industry, emission from motor vehicles. municipal emission due to house furnaces and natural phenomena. The results or screening measurements or size distribution performed in several places located on highly populated areas in Upper Silesia, Poland arc described in this paper. The applied equipment makes it possible to cover the range from several nanometers up to 20 rim, practically all particles that belong to the rcspirable class. Obtained results prove that a lot of particles having a size of the order or submicrons are produced close lo high density tra Ilic roads. This concentration strongly changed in time.

In this study the effect of anionic surfactants on the morphology of activated sludge floes and biomass activity is quantitatively described. Three anionic surfactants: sodium dodecyl sulphate, sodium alkylbenzene sulphonate and sodium alkyltrioxyethylene sulphate were tested. The batch experiments were performed for a wide range of initial concentrations of anionics in wastewater from 2.5 to 2500 mgdm3. In spite of different chemical structure the action of all tested anionic surfactants resulted in the decrease of activated sludge floes dimensions at the similar level. It occurred that in the range of anionics concentrations, which are typical for domestic wastewater (2.5-25 mgdm3), they contributed to the decrease of mean projected area of floes by about 30%, whereas at the concentrations of 250 and 2500 mg-dm3 mean projected area decreased usually by 50-60%. Sodium alkylbenzene sulphonate exerted the strongest inhibition effect on dehydrogenase activity of activated sludge biomass. This effect coincided with the decreased degrees of removal for this surfactant and its biodegradation products, especially at its lower initial concentrations in wastewater.

Controlling low-temperature drying facilities which utilise nonprepared air is quite difficult, due to very large variability of ventilation air parameters - both in daily and seasonal cycles. The paper defines the concept of cumulative drying potential of ventilation air and presents experimental evidence that there is a relation between this parameter and condition of the dried matter (sewage sludge). Knowledge on current dry mass content in the dried matter (sewage sludge) provides new possibilities for controlling such systems. Experimental data analysed in the paper was collected in early 2012 during operation of a test solar drying facility in a sewage treatment plant in Błonie near Warsaw, Poland.

The paper presents a method of computing electrical and mechanical variables of BLDC motors. It takes into account electrical, magnetic and mechanical phenomena in the power supply-converter-BLDC motor-load machine system. The solution to the problem is the so-called circuit-field method. The results determined with the use of time stepping finite element method were used as the parameters of equations of the developed mathematical model. Losses in the motor, losses in transistors and diodes of the converter as well as the actual back EMF waveforms, variable moment of inertia and variable load torque are accounted for. The designed laboratory stand and the test results are presented in the paper. The experimental verification shows the correctness of the developed method, algorithm and program. The developed computational method is universal with respect to different electromechanical systems with cylindrical BLDC motors. It can be applied to electromechanical systems with BLDC motors operating at constant but also variable load torque and moment of inertia.

During implementation of construction projects, durations of activities are affected by various factors. Because of this, both during the planning phase of the project as well as the construction phase, managers try to estimate, or predict, the length of any delays that may occur. Such estimates allow for the ability to take appropriate action in terms of planning and management during the execution of construction works. This paper presents the use of the non-deterministic concept for describing the uncertainty of estimating works duration. The concept uses the theory of fuzzy sets. The author describes a method for fuzzy estimations of construction works duration based on the fact that uncertain data is an inherent factor in the conditions of construction projects. An example application of the method is presented. The author shows a fuzzy estimation for the duration of an activity, taking into consideration the distorting influence caused by malfunctioning construction equipment and delivery delays of construction materials.

In her article the Author follows the gradual change in Feliks Koneczny's approach to history and its understanding. Feliks Koneczny, a Polish historian from the turn of I 9th/20th centuries, started as a professional historian, to include philosophical reflections in his works and end with a work devoted to moral issues.

Introduction: The prolongation of the life of men results in the growing number of people suffering from benign prostatic hyperplasia (BPH). In 2010, BPH concerned more than 200 million men in the whole world, which at that time made up 6% of the population of men at large. Currently, the population of men in the world amounts about three billion six hundred million. The modern surgical treatment of BPH consists of minimally invasive techniques, including laser systems.

Aim: Evaluation of the eff ectiveness of photoselective vaporization of the prostate (PVP) on the basis of subjective parameters assessed by patients using IPSS and QoL questionnaires as well as objective parameters obtained from results of urodynamic tests.

Material and Methods: Between 2012 and 2015, 120 patients with benign prostatic hyperplasia were included in the study and underwent PVP. Finally, 77 patients were included in the study. In all patients, IPSS and QoL sheets were carried out 1, 6 and 12 months, and urodynamic tests 12 months after the surgical treatment.

Results: The statistically signifi cant change in the value of each parameter assessed: decrease in the IPSS, QoL, PVR, Pmax, Pop, the degree of obstruction according to Schäfer and ICS nomogram, and an increase in the values of Qmax and Qave.

Conclusions: Photoselective vaporization of the prostate is an eff ective method of therapy in patients with benign prostatic hyperplasia.

Philosophical concepts have always been closely related to the development of basic sciences. For example, great mathematical theories put forth at the turn of the century, and general theory of relativity were crucial for the advancement of physical sciences and at the same time had a great impact on the formation of a new science philosophy. They also initiated a new era of exploring the Universe, thus opening many issues in the fields of astrophysics and astronomy. In biology, the theory of evolution has greatly impacted the understanding of such fundamental issues as the origin of living species and the occurrence of the phenomenon of life on Earth. Another breakthrough in life sciences was a result of the progress in molecular biology which concerned sequencing genomes and modification of genetic resources of living organisms. These great achievements have led to formation of several new fields of life sciences such as: synthetic biology, systemic biology as well as personalized medicine.