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Abstract

The aim of this paper is to present an overview of protected areas in Polish seaside spa towns in order to preserve their nature value while focusing on the spatial order. Analyses were conducted considering the status of works on the Landscape Act concerning the interior of Polish spa towns and advantageous effects of that Act in the town space. This review paper presents protected areas based on the resources of the Central Register of Nature Conservation Forms (Centralny Rejestr Form Ochrony Przyrody CRFOP) available at the website of the General Directorate for Environmental Protection (Generalna Dyrekcja Ochrony Środowiska GDOŚ), which data may find multiple uses. The material for analyses is related to all the six Polish seaside spa towns (as for 01.2020). Polish seaside spa towns have many common natural characteristics. All of the six towns are located on the Baltic Sea, have sandy beaches and dunes and they are situated in the vicinity of protected areas. Frequently a green belt, typically a pine forest, separates the seaside zone from the town. Despite its very long seaside line Poland in 2019 has only six seaside spa towns (Kołobrzeg, Świnoujście, Sopot, Kamień Pomorski, Ustka, Dąbki).

Abstract

This paper presents a proposal for updating and expanding the teaching of technical university students concerning the subject of roofs. Through the analysis of Polish textbooks and teaching studies, a lack of information on retractable roofs was identified. As a consequence, a lecture was prepared to fill this gap and presented to students of the Faculty of Civil Engineering and to teaching staff of the Silesian University of Technology. The main components of the lecture are presented in this article. Furthermore, a discussion was undertaken to analyse the possibilities of incorporating new content (in the form of supplementary material) into the currently run courses as well as into optional classes such as student workshops and optional facultative courses.

Abstract

One of the modern methods of reducing vibrations of plates and beams is using piezoelectric materials in the form of distributed elements or patches (applied in a passive or an active system). However, for the multimodal response of a structure, there is no possibility to place the actuators in exactly the areas with maximum curvature values for each mode. Additionally, in the case of passive multimodal suppression systems – in which energy is needed to be supplied to the system – there is the necessity to create a complicated electrical circuit. The particular electrical shunts of the circuit are tuned to the specific vibration forms which require damping. The main objective of this article is to show the possibility of creating a multimodal vibration suppression system with typical resonant shunts and proposed second slightly modified.

Abstract

The proposed self-adjusting mechanism consists of a carousel rotor with a vertical axis consisting of two kinematically connected flat blades. The torque of this rotor can change the position of the directing unit and additionally the position of the main propeller in order to direct the wind stream or save the main rotor when the wind is too strong. The theory, principles of operation, and the properties of the self-adjusting system were illustrated by formulas and graphs. Based on research conducted in a boundary layer wind tunnel, the values of the aerodynamic coefficients of the flat blades were determined, and then the power and propeller torque of the rotor were found as a function of the angle of wind attack. A computational procedure provides kinematical and force relations as well as the resulting torque diagrams of the rotor. An example of the use and the design structure of a self-adjusting unit in the case of a horizontal axis wind turbine is presented.

Abstract

The adsorption of Diphenolic acid (DPA), 2,4-Dichlorophenoxyacetic acid (2,4-D), and 2-methyl-4-chlorophenoxyacetic acid (MCPA) were examined in aqueous solution using activated carbon rice straw. The rice straw was activated by using two reagents, zinc chloride and phosphoric acid and named as RSZ, RSP, respectively. The results showed that both carbons have a relatively high adsorption capacity. Concerning the adsorption kinetic, the second-order model has better fit than the first model to experimental data. The adsorption yield of both carbons increased in the order: DPA < 2,4-D < MCPA. The pore volume diffusion model satisfactorily fitted the experiment on both carbons. Furthermore, solution pH has a high influence on the adsorption capacity for both carbons. The adsorption mechanism of selected pollutants onto carbon samples has been controlled by dispersion interaction π-π electrons and electrostatic interaction, moreover, the contribution of pore volume diffusion is the controlling mechanism of the overall rate of adsorption.

Abstract

Water based paints are increasingly attracting interest mainly with a view to reducing air pollution with volatile organic compounds (VOC). However, the protective properties of water-based paints are inferior to those of solvent-based paints and so new ways to increase the resistance of water-based systems are sought. The present contribution describes the preparation and testing of environmentally friendly anti-corrosion paints based on novel water-based self-crosslinking acrylate latexes containing appropriate pigments and ZnO or MgO nanoparticles at a concentration of 1.5 % (with respect to the monomers) compared to the same systems free from the nanoparticles. Both the effect of the MeO nanoparticles and the effects of the pigment species and particle shapes on the paint film properties were examined. The MeO nanoparticles were found to improve all the properties tested. The latexes with MgO exhibited the highest resistance to flash corrosion while the latexes with ZnO exhibited the highest anticorrosion resistance. Furthermore, the systems with the calcium-aluminium polyphosphosilicate based pigment were superior to all the remaining systems in this respect. It is concluded that binders with nanoparticles can be used as a basis for anticorrosion coatings provided that a suitable pigment is selected.

Abstract

Zeolites are nanoporous alumina silicates in a framework with cations, exhibiting ion-exchange properties with metal ions making them possible antimicrobial materials. The aim of this study was to evaluate the antimicrobial activity of ion-exchanged zeolites and the toxic potential of these materials. Zeolite-Co2+ and Li+ exhibited the most effective inhibition on Staphylococcus aureus growth than in other microorganisms (Escherichia coli and Pseudomonas aeroginosa) in low concentrations. Zeolite-Cu2+ presented higher zone of inhibition when tested against Candida albicans, while Zeolite-Zn2+ showed similar effectiveness among all the microorganisms. When ion-exchanged zeolites were used in effective concentrations to achieve antimicrobial activity, no alterations against bioindicators organisms as Artemia sp. and L. sativa were found and, in addition, they have non-significant result in terms of DNA cleavage activity. Zeolites have advantage of releasing slowly the metals loaded and this characteristic can to be considered promising as potential antimicrobial materials in concentrations safe for use.

Abstract

Prebiotics can play an important role in functional foods. In this paper, casein and five probiotics were selected to study the effects on ACE inhibitory peptides in fermented milk of L. bulgaricus LB6 through Plackett-Burman design, so as to improve the production of ACE inhibitory peptides. The results showed that xylooligosaccharides (XOS), fructosaccharide (FOS) and inulin had the most significant effect on the yield of ACE inhibitory peptides. Optimization added the amount of the three prebiotics added, that is, the amount of XOS added was 0.7%, the amount of FOS added was 1.1%, and the amount of inulin added was 0.7%. It provides a basis for subsequent optimization experiments.

Abstract

In this study, optimal conditions to form cellulose-MgO nanocomposite with antibacterial properties were evaluated. Applying the Taguchi method, 9 experiments were designed and the effects of different concentrations of biopolymers cellulose (0.5, 1 and 2 mg/ml), MgO nanoparticles (2, 4 and 8 mg/ml) and stirring times (30, 60 and 90 min) on antibacterial activity of synthesized nanocomposites were assessed. The characterizations of products were investigated by dynamic light scattering (DLS), raman spectroscopy, scanning electron microscope (SEM), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The results showed that the nano-composite produced in the conditions of experiment 9 (MgO 8 mg/ml, cellulose 2 mg/ml and stirring time of 60 min) has the strongest antibacterial activity. The outcomes of both methods of colony forming units (CFU) and disc diffusion indicated that the antibacterial activity of cellulose-MgO nanocomposite was significantly higher than its components (P <0.05). Thermal analysis indicated improvement in the thermal stability of the cellulose biopolymer after the formation of the nanocomposite. Due to the improvement of the antibacterial properties of cellulose-MgO nanocomposite compared to its components, we can use it as a new antibacterial agent in the fields of pharmaceutical, medicine and dentistry.