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The die-off of the unique animals is bringing overfishing, pollution and other pressing environmental issues into focus.
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The subject of this study is 2-phenylbenzimidazole-5-sulfonic acid (PBSA), which is one of 26 filters used forpersonal protection in the European Union. The aim of the study was to investigate the stability of 2-phenylbenzimidazole-5-sulfonic acid and its sodium salt under the influence of various agents. The study has shown that UV radiation, pH value, hydrogen peroxide are important factors limiting the stability of PBSA. The significance of the study is expanding the knowledge about the stability of PBSA.
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The aim of the study was to analyze selected parameters of air in a room with a book collection taking into account the influence of components of mechanical ventilation on air flow, temperature and velocity distributions. The values of air parameters, obtained by numerical calculations in DesignBuilder, were compared with the recommended ranges. The temperature and air velocity in the cross-sections through the part of the room with the book resources were referred to the prescriptions and standards relating to the conditions in libraries. The parameters of air in the space for permanent stay of employees were compared with the guidelines corresponding to the conditions of thermal comfort.
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Modification of polymer materials by various kinds of fillers is presently applied very often in massive production. This is due to the need for materials with better properties and lower prices for parts. One of the newest solutions is the filling of polymers with fly ash. This results in a change in products properties and reduction the amount of waste in the form of ashes. This article shows the results of investigations of thermomechanical properties of polyamide 6 modified by fly ash from the combustion of biomass. Comparative analysis of unfilled polyamide and polyamide composites with the addition of 5%, 10% and 15% of fly ash was performed. The specimens were obtained using injection moulding technology. The commercial name for the Polyamide 6 used in this study is TARNAMID T-27 and was manufactured by Zakłady AzotoweTarnów. Fly ash manufactured by GDF Suez Energia Polska S.A. was applied as a filler. The investigations of mechanical properties were made using a harness by pressing ball method, impact strength by Charpy method and tensile strength. Differential scanning calorimetry (DSC), softening temperature by Vicat, and colour investigations were also performed. Pictures of microstructure were made.
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This paper reviewed the existing literature on effectiveness of construction waste minimization in Nigeria with particular interest in Bauchi State. The study highlighted the menace of construction waste to the environment. The Nigerian construction industry comprises foreign and indigenous firms which are classified into small, medium and large according to their level of capitalization and annual turnover. In the real industrialized countries, the construction industry can be responsible for up to 20 % of the GDP and employs up to 12 % of the total labour force. In Nigeria, the sector contributes 3.2 % of GDP. This is a clear indication that construction industry in Nigeria failed to meet expectations of governments, clients and society. The material and method of this research study utilized a secondary source of data. A critical review of this recent journal articles posited new findings of effectiveness of construction waste minimization. To ascertain the actual happenings in the construction industries within and beyond the study area. The findings of this research study indicated that environmental pollution is caused by construction waste in the study area. It is also revealed that indigenous firms generate large volume of construction waste. It was evident that construction waste is ineffective to the health condition of the environment. The conclusion is drawn from the study also revealed that different approach and method should be applied to curtail and minimize construction waste effectiveness in the study area.
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Optical fiber cables are materials whose core is made of silica and other materials such as chalcogenide glasses; they transmit a digital signal via light pulses through an extremely thin strand of glass. The light propagates and is being guided by the core which is surrounded by the cladding. Light travels in the optical fiber in the form of total internal reflection in the core of the fibers. The flexibility, low tensile strength, low signal loss, high bandwidth and other characteristics of optical fibers favors it for use as a delay medium in many applications. Another favorable characteristic of optical fiber delay lines is are their relative insensitivities to environmental effects and electromagnetic interferences. The immunity of optical fibers to interferences and their less weight added advantages to it for use as delay medium. Single-mode and multi-mode are the two most popular types of optical fibers. Single-mode fibers have good propagation and delay properties with a minimal loss that allows the signal to propagate in a large distance with insignificant distortion or attenuation. The percentage of power transmission of single-mode fibers is found to be higher than that of the multi-mode fibers. It is, therefore, a preferred type for use as a delay line. In this paper, relative studies of the two optical fibers modes, and the results of power input/output measurement of the two modes are presented with a view to coming up with a better type for use as a delay medium.
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In this article, the authors carried out a research on a typical linear wall-foundation thermal bridge of a low-energy residential building, based on the principles of energy and economic efficiency. The empirical study showed that the most economical way to heat the foundation of a A + class residential building is with a continuous insulation thickness of 100 mm XPS200 (T3 position). In this position the linear wall-foundation thermal bridge is equal to 0,13 W/(mK). The annual cost per 1 meter of this connection is 0.84 €/m. The simple payback period is 30 years. By heating the foundation with 250 mm insulation thickness layer, the standard linear thermal bridge size (0.10 W/(mK)) is achieved, however this solution exceeds the economic life cycle of the material, and the payback can reach 65 years. Under other preconditions, the research shall be reviewed.
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The paper presents methods of forecasting electricity by means of a photovoltaic system. A short-term forecast e.g. a day-ahead forecasting as well as a forecasting method that uses neural networks of the MPL type have been pre-sented. The paper also displays a comprehensive set of explanatory variables for forecasting models. Prognostic model parameters have been determined and forecasts have been made for several time periods (e.g. full-year forecast, half-year forecasts) and final conclusions have been formulated..
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The objective of this paper was determination and measurement of the effect on the environment that application of central softening of water from the Grotowice intake can have. In order to carry out the said analyses, two levels of water softening were considered, i.e. up to hardness at the level of 200 mgCaCO3/L and 250mgCaCO3/L. For this purpose Grotowice intake collecting water with very high hardness was chosen. Several household appliances which use hot water during their work have been selected for analysis. In addition, the required data were collected and an environmental impact assessment has been prepared (carbon dioxide emissions based on energy consumption of individual appliances, the amount of phosphorus emissions present in used detergents, the amount of waste produced after consumption). As shown by the results of the conducted analyses, limitation of the hardness level of water taken at the Water Treatment Station in Grotowice has a significant effect on reduction of emission of contamination to the environment.
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The aim of the preent study was to assess the possibility of use economic analysis to compare selected filter beds used in water treatment plant. There were considered selected masses which are commonly used for removal iron and manganese from the groundwater. Water purification with these minerals is one of the most important processes in water technology. Underground water taken by wells is polluted with increased concentration of iron and manganese. That is why many of individual, urban and also industrial water treatment plants do their best to remove them from the water. Thousands of tons of different filter masses set for iron and manganese purification from the water are bought on the Polish market every year. Tests carried out within experiments are presented in this paper, which include analysis of filter beds such as: Filtersorb FMH, Filter AG, Pyrolox and Defeman. Selected masses differ with origin, density, mesh size, diameter and price. For the complete economic analysis of the selected filters there considered the following factors affected the operating costs: cost of filter beds, environmental fees for water intake, costs of equipment to aerate the water, cost of chemical reagents for the regeneration of beds, cost of a dosing pump, costs of reagents for filter regeneration. The analysis showed that the cost of exploitation of the filter depends mainly on the purchase and filtration rate. In addition, significant parts in the costs of exploitation of the filter is environmental fee for water intake, but lower than buying filtration bed. The cheapest in the exploitation turned out to be Defeman and Filter-AG, the most expensive - Filter-FMH.
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This paper illustrates an experience related to the use of 3D printing technology during the fabrication of elements for a supporting arm. The arm was a part of a test stand designed for an investigation of rotating wheels in contact with the ground. One of the crucial elements of a supporting arm is the hub, which was originally made from aluminium, however it was decided to replace it by the one made from ABS using 3D printing technology. The author decided to describe difficulties encountered during fabrication of the hub, together with a set of recommendations for future use of 3D printers.
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The issue of emulsion flow through porous media plays an important role in the development of land purification methods from various oily substances, as well as during the oil extraction process. The concentration of the emulsion dispersed phase exerts a strong influence on the rheological properties. The oil in water emulsions (O/W), that have a concentration of less than 0.5 (or 50%), show Newtonian behavior, and those with higher concentrations non-Newtonian. The flow of such systems through the structure of the porous medium is, therefore, also dependent on the variable rheological properties of the liquid. When the emulsion flows through the porous medium, a reduction of the relative permeability occurs. Due to that the transport may be very effectively limited, as the pores of deposit are being blocked by oil droplets. The paper presents studies on emulsion flow, with various concentrations, through a granular bed. It allowed to track changes in the permeability of the deposit over time. The results of experimental studies of transport and elution of highly concentrated emulsions from granular structures are also presented. This enabled tracking of changes in flow resistance of the emulsion through the porous bed in time. Moreover, the development of the mathematical model, which allows us to define the relationship between the bed blockage degree and the concentration of the emulsion internal phase could be the result of the experimental works. The results of such studies are very widely used in practice, among other things, in the issues of migration of pollutants, such as petroleum substances, in the soil layers. The development of knowledge in this field may contribute to the optimization of existing oil recovery techniques and methods of remediation of soil from organic substances.
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High-density polyethylene nanocomposites with hydroxy-hepta(iso-butyl)-octasilsesquioxane (POSS-(i-Bu)7OH) and hydroxy-hepta(iso-octyl)-octasilsesquioxane (POSS-(i-Oct)7OH) as nanofillers were prepared by melt blending. The morphological, thermal and mechanical properties as well as processability of obtained nanocomposites were characterized. POSS nanofillers were homogenously dispersed in polymeric matrix. High compatibility between nanofiller and polymer induced enhanced thermal stability, Charpy impact strength and melt flow rate for composite materials. POSS particles acted also as a nucleating agent for polyethylene crystallization in the nanocomposite.
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This article presents the possibilities of using the waste material obtained from the vehicle fuel tank (high density polyethylene PE- HD) as an addition to products. The waste material is added to the original polymer in an amount of 10% , 20% and 30%. The following tests have been performed during the research: differential scanning calorimetry DSC, static tensile test, hardness degree determined by pressing a steel ball, and also optical microscopy of obtained breakthroughs in samples made of liquid nitrogen. In addition, there has also been performed an analysis of mixture of original polyethylene that contains 10%, 20 % and 30 % of HD - PE polymer, which has been turned back for recycling from the production line. The aim of the research is to determine the recycling possibilities of polymeric materials obtained from the waste that emerged on the production line and in the fuel tanks of vehicles which were withdrawn from use as materials that during the utilization process have been subjected to a long-term connection with petroleum. Description of the mechanical and structural properties is an attempt to answer the question concerning usefulness of polymeric materials after utilization.
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Comparative analysis of thermomechanical properties of polyamide and polyamide composites with addition of 30% of glass balls was performed. The specimens were obtained using the injection moulding technology by means of KraussMaffei KM65-160C1 injection moulding machine. The non-filled polyamide and part of components were injected using the parameters recommended by the manufacturer. A reduced value of mould cooling temperature was used for the other non-filled specimens. The differential scanning calorimetry (DSC), hardness testing, impact strength testing, bending resistance and dynamic mechanical thermal analysis (DMTA) were also performed.
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Nowadays it can be seen that interest in renewable energy is growing up significantly. Among others we can observe huge development of fuel cells. These devices are used mostly for power production but it is not their only application. There are lots of different types of fuel cells. One of the lasts inventions are microbial fuel cells (MFC), which are based on use of microorganisms. There are lots of research focusing on constructions and application of MFC in different ways.
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The thermo-magnetic convection of paramagnetic fluid in a strong magnetic field is studied. The fluid is aqueous solution of glycerol with gadolinium nitrate hexahydrate. Experimental enclosure – rectangular vessel with aspect ratio equal to 2 – was heated from the bottom, and cooled from the top. Temperature difference between top and bottom walls was kept constant ΔT=5K. The magnetic induction was increased stepwise from 1 to 10 [T]. On the basis of temperature measurements, analysis of heat transfer and fluid flow were performed, showing that magnetic field strongly enhance heat transfer (over 300%) and that aspect ratio of the enclosure has a great influence on heat exchange in the system.
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Polymer matrix composites used for different cable coatings or pipes, are fabricated from materials containing various kinds of powder fillers or fibrous. Properties and structure of these materials depend on the type of added ingredients, their miscibility and quantity. Proper processing method also plays an important role, which allows for obtaining products of homogeneous reproducible properties. The composition was prepared by extrusion with changed processing parameters according to solid plastics. The roughness of obtained shapes was measured with the use of linear method. Results shows that adding blowing agent has a significant influence on mechanical properties.
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The aim of this research was to compare the effectiveness of highly-selective chromatographic PAHs determination method with the new, simpler, non-selective spectrophotometric method, designed for the rapid monitoring of PAHs contamination level in soil. The conducted experiment includes the 2 series of PAHs content determinations, in 4 types of soils, with use of HPLC and spectrophotometric techniques. The obtained results, showed that the developed, PAHs content in soil determination method, can be used for quick and non-specific environmental monitoring of soil. However the effectiveness of this method is dependent on the content of organic matter in the analyzed soil samples.
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This study presents a comparative analysis of specimens before and after photochemical and electrochemical ageing processes. The specimens were cut out of the pipes obtained through extrusion. The examinations were carried out for two commercial grades of polyethylene. Ageing with UV radiation was carried out using a gas discharge lamp, whereas simulation of electrochemical ageing was performed in a water solution of NaCl. Tensile strength testing, differential scanning calorimetry, colour and gloss measurements and hardness testing using the method of ball indentation were carried out for both types of specimens (after ageing and without ageing). Analysis of the results of the examinations revealed that ageing caused significant changes in properties of the specimens. In the samples after ageing was observed decrease in tensile strength. Found a decrease in the degree of crystallinity and changing temperatures physical changes. In the samples after ageing was observed different values of the parameters describing the colour. In samples after ageing also reported a reduction in gloss and hardness.
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