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PL
Biogazownia niejedno ma imię. Wiele wskazuje na to, że w dobie transformacji energetycznej tego typu rozwiązania będą zyskiwać na atrakcyjności, szczególnie że ich działanie wpływa korzystnie na środowisko naturalne. Skąd zatem można pozyskiwać substraty? Oto kilka przykładów wraz z podaniem placówek zajmujących się ich wykorzystaniem.
PL
Problemy gospodarcze, które pojawiły się w Polsce, dotykają społeczeństwo nie tylko, jeśli chodzi o wzrost cen żywności (inflacja najwyższa od 25 lat), ale zwłaszcza jeśli chodzi o wzrost cen za energię cieplną i elektryczną oraz transport. Tego rodzaju kłopoty pojawiły się już podczas szalejącej pandemii COVID-19 w 2020 i 2021 roku, a spotęgowały je z pewnością konflikt zbrojny między Rosją a Ukrainą oraz wymogi, jakie nakłada na Polskę Komisja Europejska m.in. w związku z rozpowszechnieniem produkcji energii odnawialnej.
EN
The hereby work presents the iron-nickel alloys electroplated on the different metallic substrates (aluminium, silver, brass) using galvanostatic deposition, with and without presence of the external magnetic field (EMF). The films were obtained in the same electrochemical bath composition - mixture of iron and nickel sulphates (without presence of additives) in the molar ratio of 2 : 1 (Ni : Fe), the electric current density (50.0 mA/cm2), and the time (3600 s). The mutual alignment of the electric (E) and magnetic field (B) was changeable - parallel and perpendicular. The source of EMF was a set of two permanent magnets (magnetic field strength ranged from 80 mT to 400 mT). It was analysed the surface microstructure, composition, morphology, thickness and the mechanical properties (roughness, work of adhesion). The surface morphology and the thickness of films were observed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). The elemental composition of all FeNi films was measured using Wavelength Dispersive X-Ray Fluorescence (WDXRF). The crystalographic analysis of the deposits was carried out by X-Ray Diffraction. Depending on the used substrate, modified external magnetic field orientation influenced the tribological and physio-chemical properties of the deposited layers. The diamagnetic substrates and EMF application reduced the FeNi thickness and the average crystallites size, in contrast to the paramagnetic substrate. Parallel EMF increased the value of the tribological parameters for CuZn and Ag but decreased for Al. The content of FeNi structure was rising in the case of diamagnetic substrate and the dependence was opposite on the paramagnetic substrate.
EN
Polymermineral material "PMM" has multiple cycles of swelling and drying. It does not decompose under soil, biological and atmospheric influences and is environmentally safe. By adding the proportion of up to 30 g/kg of PMM additive to soil and tamping, we get a waterproofing material that can be used in urban construction and water supply. Taking into account the fact it is not always technically possible to carry out high-quality ramming when repairing channel walls, the task was to conduct an experimental study in order to determine the total moisture content of the mixture of PMM additive with soil. Experimental results of laboratory studies show that when PMM is added to the soil at a ratio of 30 g/kg under evaporation conditions, the mass of excess water in the substrate increases with time.
EN
The content of heavy metals in soil should be continuously monitored, especially in organic crops. Exceeding the permissible concentrations of these elements may lead not only to inhibition of plant growth but also to ingestion into the organisms of animals that feed on these plants. Heavy metals usually enter the soil via precipitation or manure. There is a noticeable increase in interest in digestate for fields fertilization. Therefore, the authors decided to test the heavy metal content in substrates (slurry and solid input) and digestate. The 15x3 samples tested showed that only trace amounts of heavy metals were present. The study shows that the content of these elements in the digestate is not the sum of the elements supplied to the digester with the substrates. In most of the samples tested, lead concentrations did not exceed 5 mg‧kg-1. The lowest amounts of cadmium (an average of 0.28 mg‧kg-1) were observed in the slurry, and the highest (an average of 0.34 mg‧kg-1) in the solid substrate fed to the digester. Slurry had the lowest mercury and cadmium contents (average 0.012 mg‧kg-1 and 5.8 mg‧kg-1). The highest concentration of chromium was registered in the digestate (average 3 mg‧kg-1) and this was on average 0.3 mg‧kg-1 higher than the feedstock and 0.5 mg‧kg-1 than the slurry.
PL
Zawartość metali ciężkich w glebie powinna być stale monitorowana, szczególnie w przypadku upraw ekologicznych. Przekroczenie dozwolonych stężeń tych pierwiastków może doprowadzić nie tylko do zahamowania wzrostu roślin, ale także do wchłonięcia przez organizmy zwierzęce, które się nimi żywią. Metale ciężkie trafiają do gleby zazwyczaj drogą opadów lub nawozu. Widoczny jest wyraźny wzrost zainteresowania pofermentem do nawożenia pól. Zatem, autorzy zdecydowali o zbadaniu zawartość metali ciężkich w substratach (w gnojowicy i odpadach stałych) oraz w pofermencie. Zbadane próbki wykazały wyłącznie śladowe ilości metali ciężkich. Badanie pokazuje, że zawartość tych elementów w pofermencie nie jest sumą pierwiastków dostarczonych do fermentora z substratami. W większości zbadanych próbek, zawartość ołowiu nie przekraczała 5 mg‧kg-1. Najmniejszą ilość kadmu (średnio 0,28 mg‧kg-1) zaobserwowano w gnojowicy a najwyższe (średnio 0,34 mg‧kg-1) w stałym substracie zasilającym fermentor. Gnojowica miała najniższe stężenie rtęci i kadmu (średnio 0,012 mg‧kg-1 oraz 5,8 mg‧kg-1). Najwyższe stężenie chromu zostało zanotowanie w fermentorze (średnio 3 mg‧kg-1) czyli średnio 0,3 mg‧kg-1 wyższe niż surowiec oraz 0,5 mg‧kg-1 niż gnojowica.
PL
Autor przedstawia problematykę układania płytek wieloformatowych w kontekście przygotowania podłoża i doboru odpowiedniej chemii budowlanej.
EN
The author presents the issues of laying multi-format tiles in the context of substrate preparation and the selection of appropriate construction chemicals.
EN
This paper proposes the design and simulation of 2×2 circular patch antenna array working at 28 GHz by using four inset feed micro strip circular patch antennas to achieve beam forming with directivity around 13dB which is required to overcome part of high path loss challenge for high data rate mm-5G mobile station application. Four element 2x2 array consists of two 1x2 circular patch antenna arrays based on power divider and quarter wavelength transition lines as a matching circuit. The designed antenna array is simulated on RT/duroid 5880 dielectric substrate with properties of 0.5mm thickness, dielectric constant ε r =2.2, and tangent loss of 0.0009 by using Computer System Technology (CST) software. The performances in terms of return loss, 3D–radiation pattern is evaluated at 28 GHz frequency band. The design also includes the possibility of inserting four identical 2x2 antenna arrays at four edges of mobile station substrate to achieve broad space coverage by steering the beams of the mobile station arrays.
EN
The monitoring studies were carried out on the territory of the Lviv wastewater treatment plants. The volumes of accumulated stocks of the sludge site were determined, its qualitative and quantitative indicators were identified, and the presence of limiting factors was established. On the basis of the obtained data, the 2-D models characterizing the vertical and horizontal accumulation of elements were created. The mioindication studies were conducted to determine the feasibility of using sewage sludge as a growth substrate. Modeling was performed to determine the potential area of reclaimed land.
10
Content available remote Mikropale kotwiące
EN
Any type of material that increases soil yield, both qualitatively and quantitatively, to strengthen the soil and increase its fertility is called fertilizer. The current study examines the production of a new effective fertilizer. Results presented involve effects of new bioorganic-mineral compositions obtained from the combination of vermicompost and sulphur-containing waste from sulphuric acid production on the yield and quality of tubers (beets, carrots). An increase in the yield of tubers has been found to be 1.13–1.25 times when the bioorganic-mineral composition (~20 Mg∙ha–1) is introduced into the sierozem (serozem) soil. The best results are obtained with mass ratios in the range 30–45 and 55–70 for vermicompost and sulphur-perlite-containing waste, respectively. The effectiveness of the mixture of vermicompost and sulphur-containing waste is explained by the increased synergistic interaction of these components. The proposed composition has high structure-forming, water-retaining, nutritional and biologically active properties.
EN
Animal biomass is an important substrate in the anaerobic digestion process. The implementation of a waste technology for energy production, such as the production of biogas from animal waste, has been recognized in many countries as one of the best ways to achieve the Sustainable Energy Development Goals. Without a systematic review of resources and accurate estimation of available sources in terms of the amount of potential electricity, it is impossible to manage biomass rationally. The main aim of the article was to present a new tool for assessing the biomass of animal origin and estimating its potential energy through a computer database, which will be widely available in the end of 2020 to show results from the calculation using the database. This tool is configured to enter the data on the developed and undeveloped biomass resources in production of farm animals in rural areas in Poland. Calculations from the database show the biogas potential of swine and cattle manure and slurry in Poland, which is approximately 5.04 billion m3, with a 60% share of methane in biogas. It is the value of approximately 3.03 billion m3 of methane. It is worth underlining that slurry and manure are not high-energy substrates; therefore, it is necessary to introduce more energetic substrate streams to improve the biogas plant efficiency.
13
Content available remote Przygotowanie podłoży pod prace glazurnicze
PL
Przedmiotem artykułu są podłoża pod prace glazurnicze. Autor porusza trzy kluczowe zagadnienia: znaczenie równego podłoża, wyrównanie chłonności podłoża oraz zabezpieczenie przed wilgocią. Omawia także tematy układania płytek na gołe mury, tynki i podłogi.
EN
The subject of the article are substrates for laying tiles. The author discusses three key issues: the importance of even surface, levelling the absorbency of the substrate and protection against moisture. He also discusses the topics of laying tiles on bare walls, plaster and floors.
EN
The main ways of sewage sludge disposal in the European Union and Ukraine were considered. The main problems of sludge utilization in Ukraine were identified. Research on the possibility of using a substrate based on sewage sludge for biological reclamation of disturbed lands was conducted. The quality of the sludge from Lviv WWTP was determined. The best substrate composition for biological land reclamation was determined by using bioindication. It was established that the use of settled sludge observed inhibition of plant growth and development. Introducing additional components to the substrate, in the form of sorbents, makes it possible to increase the content of sewage sludge. Positive changes in plant growth and development when using a soil-based substrate, sewage sludge and sorbent were observed.
EN
Some clinical studies reported that glucose variability increased the risk of developing diabetes-related late complications more than constant hyperglycemia, while others claimed that the evidence was not strong enough to support such a conclusion. A few in vitro studies investigated the effect of constantly high or variable glucose levels (VGLs) on endothelial cells (EC). The first aim of this work was to review these studies and demonstrate that most of them support the notion that viability and other metabolic parameters of EC deteriorate faster in cell cultures with VGLs than in cultures with stable normal or high glucose concentration. The second aim was to verify whether the effect of glucose concentration is the same regardless of other culture conditions such as the substrate on which the cells are grown. We cultured Human Umbilical Vein Endothelial Cells (HUVECs) for 7 or 14 days in constant (5 mM or 20 mM) or variable (switching between 5 mM and 20 mM once a day) glucose concentration in culture plates, which were either not-covered with any additional substrate or were covered with fibronectin or gelatin. We assessed the cell viability using a propidium iodide test. The ANOVA revealed that HUVECs viability was affected not only by glucose concentration and duration of the cell culturing but also by the type of substrate and interactions of these three factors. In conclusion, the effect of glucose level on EC viability should not be analyzed in isolation from other culture conditions that may amplify or attenuate this effect.
EN
The paper presents the results of the analysis of diatoms from surface sediments (stones, sands) and macroflora (seagrass, macroalgae) collected at 16 sampling sites located along the inner coastal zone of Puck Bay (southern Baltic Sea) along the Hel Peninsula. The main diatom species of epilithon, epipsammon and epiphyton were characterized with respect to their autecological preferences (habitat, salinity, trophic status, saprobity). Three groups of diatoms were distinguished with respect to the type of substrate based on the results of benthic flora analysis: diatoms (i) of one type of substrate, (ii) of two types and (iii) those occurring on all types of substrates. Moreover, the distribution of benthic diatom communities indicates ecological differences in the study area. Marine and brackish-water species were observed in large numbers in the coastal zone of the Outer Puck Bay, whereas freshwater flora occurred with a higher frequency in the coastal zone of the Puck Lagoon. The content of polysaprobionts and of α-mesosaprobionts indicates that the region of the Hel Tip is highly eutrophicated and very polluted. The coast in the vicinity of Kuznica is less polluted, whereas the best environmental conditions are found in the Jurata–Jastarnia region, as evidenced by the frequency of diatoms that are β-mesosaprobionts.
EN
The article deals with the main methods of nutrient removal from wastewater, as well as presents promising technologies and techniques. Struvite was characterized by a complex phosphorus fertilizer. The influence of struvite on the processes of germination of cultivated plants was investigated. The possibility of creating a growth substrate as an inexpensive and effective alternative to the disposal of the man-made wastes that contain an organic component was identified. The composition of the growth substrate was selected to ensure its functional properties. The growth substrate was tested by bioindication. Subsequently, the modification of the substrate by adding natural sorbents.
EN
The goal of the research was to investigate the retention capacity of six green roof models (SHP1, SHP2, SHP3, SH, S, and SP) constructed with the use of the square-shaped plastic trays, Floradrain FD 25 drainage elements, SF filter sheets, and the specified extensive substrates (with or without the hydrogel amendment). The SHP1 and SHP2 models were constructed in March 2017, SHP3 and SH – in November 2017, while S and SP – in April 2018. Four models (SHP1, SHP2, SHP3, and SP) contained the plants (the goldmoss stonecrop Sedum Acre), whereas two models (S and SH) did not contain the vegetation. The substrates of SHP1, SHP2, SHP3, and SH models contained the hydrogel admixtures. The investigations were conducted with the use of simulated (and partially natural) precipitations. The water retention capacity of each green roof model was established based on the difference between the precipitation volume and the volume of runoff from a model. The results show that green roofs can be useful stormwater management tools. The calculated stormwater retention rates ranged from 29.50% to 85.15%. In most cases, the best water retention capacity was exhibited by the SHP3 model, constructed in November 2017 and planted in April 2018, containing the substrate amended with superabsorbent (cross-linked potassium polyacrylate). The similarly constructed SHP1 and SHP2 models, which were built in March 2017, in some cases had lower water retention capacity. These models contained older hydrogel and were overgrown with older, smaller, and worse looking plants, partially supplanted by mosses. Such results indicate that the efficiency of hydrogel may decrease over time. In many cases, the S (not vegetated, without hydrogel), SH (not vegetated, with substrate containing hydrogel), and SP (vegetated, without hydrogel) models had slightly lower water retention capacity. The results of investigations indicate that there was a relatively strong positive linear correlation between the retention depth and duration of the antecedent period elapsed from the preceding total (or substantial) saturation of the green roof models (labelled in this article as period since total saturation – PSTS). The weather conditions i.e. air temperature and relative humidity as well as PSTS are very important parameters that influence the retention capacity of the green roof models. The result show that duration of PSTS can be stronger correlated with the retention depth than antecedent dry period (ADP) elapsed from the end of last precipitation, regardless of its depth and intensity.
EN
By analyzing the resources of the economic infrastructure (distilleries, diaries, fruit and vegetable processing and meat processing factories) of the Biała Podlaska County, the possibilities of the biomass obtaining and creating the biogas plants basing on the agri-food industry waste were estimated. The stocking of animals was the basis for the assessment of manure and slurry resources that can be subjected to the methane fermentation process. On the basis of the data concerning the surface of the wastelands, located on the Biała Podlaska County territory, the possibilities of the biomass from special crops were specified. In the Biała Podlaska County, it was established that there are possibilities for obtaining the biomass for the biogas production: from livestock production (1 475 272 GJ/year), maize cropping in marginal lands (172 875 GJ/year) and wastes and by-products from food industry (51 081 GJ/year). The estimated potential of biogas allows for the construction of several agricultural biogas plants with a capacity of 1 MWe each, often built in Poland. The usage of the identified resources enabling the improvement of the energetic safety and also can contribute to the sustainable development of rural areas and agriculture.
EN
Abstract: Climate changes as well as the urbanisation and economic development influence the characteristics of the stormwater runoff in the cities. The sealing of drainage basin surface leads to an increase of the runoff intensity, thereby decreasing the rainwater infiltration. This situation can lead to the risk of flooding in urban areas. Therefore, especially in great cities there is a need for application of such solutions that will support the operation of the sewage systems. The examples of such solutions are, among others, the green roofs. The paper presents the results of investigation of the water retention capacity of 4 green roof models containing following growing media: (1) the typical green roof substrate without any amendments, (2) the substrate with addition of about 1 % by weight of hydrogel (the cross-linked potassium polyacrylate), (3) the substrate containing about 0.25 % by weight of hydrogel, (4) the substrate with addition of expanded clay and perlite. The models were not vegetated in order to investigate only the water retention capacity of drainage elements and substrates. The water retention capacity of green roof models was investigated in the laboratory conditions with use of artificial precipitations simulated after diverse antecedent dry weather periods (ADWP) amounting to: 1, 2, 5, 7, and 12 days. The intensities of artificial precipitations were relatively high and ranged from 1.14 to 1.27 mm/min, whereas their durations ranged from 7.75 to 12.56 min. These values of intensities and durations corresponded to the design rainfall intensities calculated using Blaszczyk’s equation for annual rain depth equal to 600 mm and the return periods ranged from 5 to 15 years. The obtained results indicate that the water retention capacity of green roof models, expressed as the volumes (or depths) of rainwater retained within their structures, increases with an increase of ADWP. Results indicate that the relation between ADWP and the amount of water retained in the layers of green roofs in the case of relatively short antecedent dry weather periods provided for the analysis (from 1 to 7 days) may be approximately linear. The results of the one-way ANOVA indicate that in the case of all models there is a statistically significant difference between the values of retention depth for specified ADWP (p < 0.001). During more than half of simulated precipitations, especially in the case of longer ADWPs lasting 5, 7, and 12 days the best water retention capacity had Model 3, with substrate containing about 0.25 % by weight of hydrogel. On the other hand, the results show that the weakest retention capacity had Model 2 (with substrate containing 1 % by weight of hydrogel). In the case of longer ADWPs (lasting 7 and 12 days) relatively weak water retention capacity had Model 4 (with substrate containing the addition of expanded clay and perlite). It can be concluded that too large amount of hydrogel added to the substrate can have an unfavourable impact on the water retention capacity of green roofs.
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