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PL
W celu obliczenia energochłonności produkcji pszenicy jarej wykorzystano dane z doświadczenia polowego prowadzonego w trzech sezonach wegetacyjnych 2009-2011. W eksperymencie pszenicę jarą nawożono dawkami azotu, wzrastającymi co 40 kg/ha w przedziale 0-120 kg/ha oraz prowadzono w układzie z i bez dodatku siarki (50 kg/ha). Na podstawie uzyskanych wyników stwierdzono, że najkorzystniejszy wpływ na plon biomasy (ziarna i słomy) i wartość energetyczną plonu biomasy pszenicy jarej Tybalt miało zastosowanie azotu w dawce 120 kg/ha oraz nawożenie siarką w ilości 50 kg/ha.
EN
To calc. the energy consumption of spring wheat prodn. of the Tybalt variety, data from a field expt. conducted in 3 growing seasons 2009-2011 were used. Spring wheat was fertilized with N doses increased every 40 kg/ha in the range of 0-120 kg/ha, in a system with and without S (50 kg/ha). Cultivation of spring wheat in conditions of high doses of N (120 kg/ha) and S addn. (50 kg/ha) increased the energy consumption of prodn.
EN
Mineral fertilisers are one of the most important nutrients that plants need in large quantities, which help to greatly increase crop yields, and yeast is considered a bio-stimulator of plants. However incorrect implementation of both can make them more susceptible to pest infestations. The mealybug, Phenacoccus solenopsis (Hemiptera: Pseudococcidae), is an economically important polyphagous pest that destroys okra plants in Egypt. This work focused on the evaluation of mealybug infestations and okra plant productivity responses to mineral fertilisers (nitrogen and phosphorus), yeast (without and with) and their interactions. This study was executed in a private okra field ("Balady" cultivar) in Luxor Governorate, Egypt, during 2021 and 2022 seasons. A split plot design was applied, where two levels (with and without yeast) were used in the main plots, where seven levels of nitrogen and phosphorus were applied in the split plots. The results indicated that the addition of 286 kg N∙ha-1, 143 kg P∙ha-1 and yeast to okra plants led to a maximum increase in the population densities of pest, and this caused a decrease in the vegetative stage of okra that would affect the final yield as compared to the other treatments throughout the two seasons. However, the application of 190 kg N∙ha-1, 107 kg P∙ha-1, and yeast to okra plants gave the highest values for vegetative growth characteristics and resulting yield during the two studied seasons. This work aids farmers in improving okra production by comprehending good farming practices and avoiding the spread of mealybugs.
EN
The article presents the results of agrochemical survey of soils of the Dolyna territorial community of IvanoFrankivsk region. The agro-productive grouping of all soils of the district was carried out. There are five agroproductive soil groups within the district: sod-podzolic soils on ancient alluvial, water-glacial deposits, moraine, and eluvium of magmatic rocks; sod-podzolic and podzolic-sod surface-gleyed medium-loamy soils; deep non-gleyed and gleyed medium-loamy sod soils and their podzolized variants on ancient alluvial, water-glacial deposits, moraine, and eluvium of magmatic rocks; brown-podzolic, sod-brown-podzolic, brown mountain-forest podzolized gleyed and surface-gleyed non-eroded and slightly eroded heavy loamy and light clayey soils; sod gleyed soils; sod-brown and meadow-brown gleyed soils on alluvial and deluvial deposits, medium-loamy stony soils.These soils exhibit acidic pH, are moderately deficient in available phosphorus, and have medium levels of potassium. They are potentially fertile but require liming and the application of organic-mineral fertilizers.
EN
The article reveals the role of soybean varieties and the value of their crops, capable of fixing atmospheric nitrogen and being a favorable predecessor in modern crop rotations, the importance of optimizing organo-mineral nutrition, seed treatment with nitrogen-fixing and phosphate-mobilizing bacteria for improving the nitrogen-fixing capacity of soybean varieties. Development of the technology of growing soybeans with environmentally friendly elements requires scientific substantiation and adaptation to the soil and climatic conditions of a particular growing zone, as well as the research of their impact on the varietal characteristics of a crop. The research outcomes conf irmed the maximum formation of the symbiotic apparatus indicators: the number and weight of soybean nodules and their intensive functioning with the formation of the highest indicators of the total and active symbiotic potential as well as the amount of biologically fixed nitrogen, it is necessary to jointly inoculate seeds with Rizoline and double application of chelated microfertilizers at microstage BBCH 12-13: Organic Balance+Azotophyte+Helprost Soybean+Liposam and at microstage BBCH 61-69: Organic Balance+Azotophyte+Helprost Boron+Liposam. At the same time, the total number of soybean nodules was formed in the Samorodok variety−50.3, of which 36.0 pcs./plant were active, in the Amadeus variety–55.6 and 40.0 pcs./plant. The total and active weight of soybean nodules in the Samorodok variety made up 515 and 399 mg/plant, and in the Amadeus variety–586 and 454 mg/plant. Indicators of total and active symbiotic potential were 31.2 and 21.6 thousand kg/day per ha in the Samorodok variety, as for the Amadeus variety–36.5 and 25.5 thousand kg/day per ha and biologically fixed nitrogen in the Samorodok variety–119.0 kg/ha, in the Amadeus variety-140.1 kg.
EN
One of the greatest threats to many lakes is their accelerated eutrophication resulting from anthropogenic pressure, agricultural intensification, and climate change. A very important element of surface water protection in environmentally conserved areas is the proper monitoring of water quality and detection of potential threats by examining the physicochemical properties of water and performing statistical analyses that enable possible exposure of unfavourable trends. The article presents the analyses of the results of measurements made in three lakes located in the Sierakowski Landscape Park. As part of the measurements, water quality indicators i.e., phosphorus, nitrogen, BOD5 and COD, were determined monthly for a year at the inflows and outflows of the studied lakes. The test results of selected water quality indicators were analysed using machine learning algorithms i.e., PCA and k-means. The conducted tests enabled statistical estimation of changes in water quality indicators in the reservoirs and evaluation of their correlation.
EN
Removing nutrients from wastewater is essential because high concentrations in aquatic systems lead to severe eutrophication problems, the most common impairment of surface waters such as lakes and oceans. Total phosphorus (TP) and total Kjeldahl nitrogen (TKN) were removed from mixed wastewater using an aerobic granular sludge process in a sequencing batch reactor (AGS-SBR). An artificial neural network (ANN) and response surface methodology (RSM) were applied to evaluate the main parameters of the process. For TKN removal, only cycle time (CT) (0.0475) was a significant variable, achieving removal efficiencies of up to 81%. In TP case removal, two parameters, VER and AR, were substantial for this process, completing elimination efficiencies of around 40%. On comparing the models with statistical indices, ANN coupled with the moth-flame optimization algorithm (ANN-MFO) demonstrated higher performance with an adjusted R2 (0.9866) for the case of TP removal and (0.9519) for TKN removal.
EN
Peatlands play a critical role in global habitats since are composed of heterogeneous materials and chemical reactions. Peatland fires significantly change the chemical characteristics of its soil, such as carbon (C), nitrogen (N), phosphorus (P) and potassium (K) content. This study aimed to measure peatland recovery only on those soil chemical characteristics based on two different times of sampling that are five years (Yr+5) and seven years (Yr+7) after the fires in 2015 (taken in 2020 and 2022). This study was conducted in the Balangan River - Batangalai River peat hydrological unit, South Kalimantan, Indonesia. Soil samples were collected at nine different locations, including are six locations in the areas that experienced fires in 2015 and three locations in the areas that did not experience fires. Those soil samples were taken with excavated pits at each sample location at each depth of 10, 20, 30, 40 and 50 cm. This study found that the carbon content in the post-fire area increased by 22.00% and in the natural area by 9.90%. The nitrogen content in the post-fire area increased by 1.94% and in the natural area by 1.17%. The potassium content in the post-fire areas increased by 16.33% and in the natural areas by 4.44%. The phosphorus content in the post-fire area increased by 3.18% and in the natural area by 5.11%. C/N ratio increased by 19.68% and C/P ratio increased by 18.24%. Overall, the increase in carbon, nitrogen, potassium, phosphorus, C/N ratio and C/P ratio in post-fire and natural peatlands indicates an improved condition. This study can provide supporting information for the regulator, management or expertise of the land and forest rehabilitation to speed up the recovery process.
EN
The utilization of sediment microbial fuel cell (SMFC) technology presents a paradigm-shifting method for converting the chemical energy obtained from organic and inorganic compounds found in sediment and wastewater substrates into electrical energy. This concept exhibits potential as an environmentally sustainable solution within the future energy sector and presents opportunities for wastewater remediation. This study aims to investigate the influence of anode modification in the SMFC system on generating electrical energy and removing pollutants in landfill leachate. The modification entails synthesizing a nanostructured copper layer on stainless steel (Cu-SS), subsequently compared to the conventional copper (Cu) anode. Results underscore the effectiveness of anode modification, as SMFCs featuring modified anodes exhibit twice the electrical output compared to unmodified counterparts. Modified anode SMFCs yield voltage and current density readings of 615 mV and 17 mA/m2, respectively. In addition to electricity generation, the study delves into the SMFC’s efficacy in nitrogen compound removal. Experimental results unveil the impressive capability of modified anode SMFCs, achieving 81.02% removal of Biological Oxygen Demand (BOD), while unmodified counterparts reach 76.64%. Furthermore, the removal percentages for ammonia, nitrate, and nitrite compounds within SMFCs equipped with modified anodes are 88%, 51%, and 13%, respectively. This comprehensive analysis underscores the multifaceted benefits of anode modification, amplifying electrical output and enhancing the SMFC’s proficiency in nitrogen compound removal, thereby contributing to its potential applications in developing sustainable wastewater treatment and energy generation systems.
EN
The duplex stainless steels show improved localized corrosion resistance and strength comparing to the austenitic stainless steels. All of the duplex stainless steels solidify as pure ferrite and the double microstructure is evolving during the solid-state, diffusion driven phase transformation. In this research nitrogen and oxygen containing argon-based shielding gases were used. It was found that the nitrogen and oxygen addition significantly increased the weld metal austenite content, up to +27%. The oxygen addition also improved the weld dissolved oxygen content with up to +0.09%, and the weld penetration depth with up to +3.3 mm.
EN
Soil degradation occurs as a result of the ingress and accumulation of excessive amount of pollutants in the soil. The article presents the results of theoretical and experimental studies of the complex effect of soil contamination (concentration of petroleum products, toxic salts, dense residue, sodium ions, sulfate ions, magnesium ions, calcium, chloride ions, bicarbonate ions) on the content of nutrients (alkaline hydrolyzed nitrogen, phosphorus, potassium, humus). A detailed analysis of scientific papers has been carried out, based on which the main scientific tasks solved in the article have been formulated. It has been established that soil-salt processes are insufficiently studied and are the object of scientific research in recent years. At the first stage of research, sampling was carried out and the content of nutrients and pollutants in the soil was determined. Determination of element concentrations was performed by collecting soil samples and their subsequent laboratory testing. At the second stage, a correlation-regression analysis of the obtained data was performed and multiple linear regressions were established. The interaction of substances in the soil was determined by analyzing the obtained multiple linear regressions. Two types of soils were studied: with chloride and with sulfate type of salinization. For soils with chloride type of salinity, dependences have been established for the content of humus, alkaline nitrogen and potassium, while in case of phosphorus multiple linear regression does not exist. For soils with sulfate type of salinization, multiple linear regression dependences of concentrations of alkaline nitrogen, phosphorus, potassium have been determined. It is established that the complex influence of the studied elements is decisive. No regression dependence was found for the humus content, which indicates that the concentration of the studied elements has almost no effect on the humus content in the soil. Comparison of the obtained multiple linear regressions with the results of laboratory studies showed a good correlation between these data series. The obtained regularities of pollutant and nutrient interactions in soils are expected in future to enable creation of scientific bases for development of new methods of desalination of soils polluted by formation waters as well as for planning effective reclamation actions.
PL
W wyniku wnikania i gromadzenia się w glebie nadmiernych ilości zanieczyszczeń następuje degradacja gleby. W artykule przedstawiono wyniki badań teoretycznych i eksperymentalnych złożonego wpływu zanieczyszczenia gleby (stężenie produktów naftowych, toksycznych soli, gęstego osadu, siarczanow, jonów sodu, magnezu, wapnia, chlorków, wodorowęglanów), na zawartość składników pokarmowych (hydrolizowanego alkalicznie azotu, fosforu, potasu, humusu). Przeprowadzona została szczegółowa analiza prac naukowych, na podstawie której sformułowano główne zadania badawcze rozwiązane w artykule. Stwierdzono, że procesy glebowo-solne zbadane są w stopniu niedostatecznym i stanowią one przedmiot badań naukowych w ostatnich latach. W pierwszym etapie badań pobrano próbki i wyznaczono zawartość składników pokarmowych i zanieczyszczeń w glebie. Wyznaczenia stężeń pierwiastków dokonano poprzez pobranie próbek gleb i ich późniejsze badania laboratoryjne. W drugim etapie wykonano analizę korelacyjno-regresyjną uzyskanych danych i ustalono wielokrotne regresje liniowe. Oddziaływanie substancji w glebie określono poprzez analizę otrzymanych wielokrotnych regresji liniowych. Badano dwa rodzaje gleb: o zasoleniu chlorkowym i siarczanowym. Dla gleb o zasoleniu chlorkowym ustalono zależności w odniesieniu do zawartośći humusu, azotu hydrolizowanego alkalicznie i potasu, natomiast dla fosforu regresja liniowa wielokrotna nie wystapiła. Dla gleb o zasoleniu siarczanowym wyznaczono zależności wielokrotnej regresji liniowej stężeń azotu alkalicznego, fosforu, potasu. Ustalono, że decydujące znaczenie ma kompleksowe oddziaływanie badanych pierwiastków. Dla zawartości humusu nie stwierdzono zależności regresji, co wskazuje, że stężenie badanych pierwiastków prawie nie wpływa na zawartość humusu w glebie. Porównanie uzyskanych wielokrotnych regresji liniowych z wynikami badań laboratoryjnych wykazało dobrą korelację między tymi seriami danych. Uzyskane prawidłowości oddziaływania zanieczyszczeń i składników pokarmowych w glebach pozwolą w przyszłości stworzyć naukowe podstawy rozwoju nowych metod odsalania gleb zanieczyszczonych wodami złożowymi, jak również planować efektywne prowadzenie prac rekultywacyjnych.
PL
W artykule zaprezentowano wyniki badań laboratoryjnych wpływu rodzaju gazu napędowego oraz objętościowego natężenia przepływu wody na skuteczność gaśniczą zaprojektowanego i wykonanego stałego urządzenia mgłowego. Jako gaz napędowy zastosowano powietrze sprężone lub azot. Podczas badań mierzono temperaturę i szybkość jej spadku, czas stłumienia płomienia testowego pożaru oraz stężenie tlenu w pomieszczeniu. Do testów pożarowych użyto stosu belek z drewna sosnowego. Największą skuteczność gaśniczą systemu mgłowego otrzymano w przypadku testu, w którym objętościowe natężenie przepływu wody wynosiło 3 dm3/s i czynnikiem napędowym był azot. Uzyskane wyniki pokazują, że rodzaj zastosowanego gazu w systemie mgłowym ma znaczenie, gdyż bierze on udział w gaszeniu, co podważa zapisy normy NFPA 750, która zakłada, że czas gaszenia wymagany przez normę jest tak krótki, że rodzaj gazu nie ma wpływu na proces stłumienia pożaru.
EN
The article presents the results of a laboratory study of the effect of the type of propellant and the volumetric flow rate of water on the extinguishing effectiveness of a designed and manufactured fixed water mist fire protection system. Compressed air or nitrogen was used as the driving gas. During the tests, the temperature and its rate of decrease, the time of suppression of the test fire flame and the oxygen concentration in the room were measured. A stack of pine wood beams was used for the fire tests. The highest extinguishing efficiency of the water mist system was obtained for the test, where the volumetric flow rate of water was 3 dm3/s and the driving agent was nitrogen. The results show that the type of gas used in the water mist fire protection system and takes part in extinguishing, which undermines the provisions of the NFPA750 standard. The standard assumes that the extinguishing time used by the standard is so short that the type of gas does not affect the fire suppression process itself.
EN
This study aimed to investigate how great cormorants and grey herons affect the density and trophic diversity of soil nematodes under breeding colonies located in Stawy Raszyńskie Nature Reserve (central Poland). Soil samples from the colonies were compared to control samples from adjacent areas unaffected by birds. Samples were taken at each site (two colonies and two relevant control sites) to a depth of 20 cm, and the soil cores were split into topsoil (0-10 cm) and subsoil (10-20 cm). A modified Baermann method was used to extract nematodes from the soil. The soil under nests supported more abundant nematode communities, but with a lower trophic diversity compared to the control sites. The cormorants had a greater impact on nematodes than the herons. We found that the external nitrogen input, the higher organic matter content and abundance of ammonifying bacteria, as well as the lower soil pH under the colonies than in the control sites, affected the nematode trophic groups in different ways. Compared to the control sites, there were significantly more bacterivorous nematodes but fewer herbivorous nematodes under the colonies. No predatory nematodes were found under the bird colonies and, in the case of the cormorant colony, no omnivorous nematodes. No significant differences in the abundance of fungivorous nematodes between the impact and the control plots were noticed. The results indicate that allochthonous input under bird colonies promotes microbial activity and the most opportunistic trophic group of nematodes, which may at least temporarily enhance decomposition and mineralisation processes and consequently affect nutrient cycling in the wetland soil.
13
Content available Nitrogen relationships in Polish cropping systems
EN
Based on FAO data, the paper presents trends in nitrogen (N) input and output in Poland. As N input (Ninp), nitrogen from mineral fertilisers, manure application, biological fixation, and deposition was included. The N outputs (Nout) include the N contained in crop harvest (main products and by-products). The trend analyses were carried out for the period before (1961-1989) and after (1990-2018) the changes in the political and economic systems. Additionally, trends in the nitrogen use efficiency (NUE) and nitrogen surpluses (NS) are presented for these periods. In both compared periods, the mean values of N budget indicators in Poland were (kg N∙ha-1 UAA): Ninp 120 and 125, Nout 61 and 84, NS 60 and 41 and NUE 53 and 67%, respectively. The estimated Ymax, which represents the Nout value reached at saturating N fertilisation, reached the values of 127 and 263 kg N∙ha-1 UAA in these periods. The difference in these values suggests a significant impact of agronomy improvement on Nout in the recent period. The trends of nitrogen within 16 regions in period 2002-2019, based on national data, resulted in a significant variation in N indicators. The values found were in the following ranges (kg N∙ha-1 UAA): Ninp 78-167; Nout 62-99; NS 15-83 and Ymax 139-317. The NUE ranged from 50-81%. The obtained results indicate that in Poland and its regions there is still a need to improve of the nitrogen efficiency.
EN
The objective of the study was to trace the variability of the hydrochemical conditions in three lakes of the West Pomeranian Voivodeship (Poland) - Starzyca, Maszewskie and Nowogardzkie in the annual cycle. The research was done in 2018-2019, and samples for analysis were collected 4 times a year. All analyses were performed applying standard methods. Such hydrochemical indices were determined as dissolved oxygen, chemical oxygen demand, content of orthophosphates, total phosphorus, nitrite, nitrate, ammonium, chlorophyll a and iron. The study showed that all lakes in the research cycle were characterised by a polymictic type of water mixing, and the trophic level, based on the adopted criteria, indicated advanced eutrophy, which may also be caused by anthropogenic pressure. Oxygen conditions characterised by deoxidation of the waters in the bottom layer in the spring and summer seasons, and clear oxygenation in the surface water layer (in Lake Maszewskie reaching even 188.5% in the spring) confirm the significant advancement of the eutrophication process. The supply of phosphorus and nitrogen in spring from pelagic waters in the waters of the examined lakes influences concentrations of chlorophyll a in the summer. The influence of “internal supply” (bottom waters and bottom sediments) on the amount of nutrients available for autotrophs is clearly visible in the analysed lakes - an increase in nitrogen and mineral phosphorus concentrations in relation to surface waters was observed in the bottom layer.
EN
The purpose of this study has been to determine the effect of fertilisation with urea-ammonium nitrate (UAN) solution enriched with P, Mg or S on the content of macronutrients in the grain and straw of maize. The following fertilisers were tested in the field experiment: ammonium nitrate, urea, UAN - 32% N; RSM+S - 26% N + 3% S; RSM+P(Medium) - 26% N and 4.80% P; RSM+P(Starter) - 21% N and 7.86% P; UAN + Mg - 20% N + 4% Mg. In each year of the experiment, significant differentiation in the contents of P, K, Ca, Mg and S in maize grain and straw was observed, depending on the applied nitrogen fertilisation. However, considering the average values from each treatment achieved over the three years, it was demonstrated that the fertilisation significantly changed only the content of P and S in grain and K and Ca in straw of maize. The removal of nutrients was the highest in the second year of the research and amounted in kg∙ha-1 : P - about 100, K - about 350, Ca - about 80, Mg - about 35 and S - about 31, which in turn were differentiated over the years of the experiment in the three years. The removal of P, K, Mg and S also significantly depended on fertilisation. Significant differences, however, most often concerned the control treatment relative to the fertilised ones. The contribution of grain to the accumulation of nutrients also varied significantly in the three years of the experiment. Significantly the lowest share of grain in terms of P and S accumulation was noted in maize grown without N fertilisation.
EN
The use of wheat straw as a cellulose containing raw material for the production of sugars and other biologically valuable products can solve the problem of food products shortages, by supplying oligosaccharides, xylose and other valuable metabolites of microbial synthesis. In our experiment, straw of annual spring wheat of the Tulkibas variety and perennial wheat of the Sova variety was added to the enzyme solutions of Trichoderma harzianum 121 and Aspergillus awamori F-RKM 0719 strains. As a result, the variant A. awamori F-RKM 0719 + Sova straw showed the highest level of nitrogen (1.05%) and protein (6.5%). The highest concentration of amino acids, 7.14 mg/ml, was found in the perennial wheat sample, while the lowest concentration, 1.32 mg/ml, in the annual wheat sample. The total carbohydrate content in the straw of the annual and perennial wheat varieties differed, namely, the perennial wheat straw with the addition of A. awamori F-RKM 0719, contained fructose in the amount of 0.0079 mg/g, while in the annual wheat it was absent. The glucose content in the perennial wheat straw was three times higher than in the annual wheat straw, 0.0144 and 0.0035 mg/g, respectively. Based on our results, we recommend wheat straw for the use as a raw material for chemical and microbiological processing.
EN
Phytoplankton growth is influenced by the presence of nutrients N (nitrogen) and P (phosphor). Each region has a specific N/P ratio, due to the influence of anthropogenic inputs. This study aimed to assess the response of phytoplankton chlorophyll-a (Chl-a) biomass due to differences in N/P ratio by the influence of river flow in the north coast of Java; Jobokuto Bay (Jepara), the coastal waters of Semarang and the front of the Cisadane river. N-nutrients were analyzed in the form of N-NO3 (nitrate), and N-NH4+ (ammonium ions), and orthophosphate ions (P-PO42-). Nutrient analysis was spectrometric, using the reduction methods (nitrate), ammonium (indophenolblue), and phosphate (molybdenum-blue). Test for site differences using Kruskall-Wallis, followed by a posthoc test. The results showed that Semarang waters had a lower N/P (Stoichiometric) ratio than Jepara and Cisadane, which can be used to predict that P nutrient input is higher than N. This high P input impacts microalgal development (chlorophyll-a). In addition, we also found Semarang waters to have higher speciation of inorganic N in the form of ammonium, which is one of the drivers of eutrophication in these waters. The use of a ratio of N/P is very important in estimating the eutrophication process and can be used to estimate the dominance of nutrients entering the water due to anthropogenic activities in the upstream area.
PL
Pomimo rosnącego zainteresowania technikami instrumentalnymi metody klasyczne nadal odgrywają kluczowe znaczenie przy oznaczaniu różnych form azotu. W artykule przedstawiono zastosowanie wybranych metod, zarówno klasycznych, jak i instrumentalnych, do oznaczania azotu całkowitego, organicznego, azotanów (V), azotanów (III), cyjanków oraz jonu amonowego.
EN
The primary aim of the current study is to investigate the influence of input parameters of near dry electric discharge machine (ND-EDM) upon the output performances including the MRR, EWR, SR and WLT for the fabricated new metal matrix composite (MMCs) of aluminum A7075 matrix nanocomposites by adding 8% of Microscopic Slide Glass Nanoparticles (MSGNPs) as reinforcements to improve the metallurgical and mechanical properties of Al-7075/MSGNP composites using stir-casting method. In (ND-EDM), the dielectric medium plays a significant role in the procedure responses. In the current work, the vegetable oil with gases, such as air, Ar, mix (Ar+N2), and Freon were used as a dielectric media. The obtained results show that the highest MRR achieved when using the vegetable oil + Freon gas, reached 29.425 mm3/min, and then 26.943 mm3/min when using the vegetable oil + Air as a dielectric. The lowest EWR achieved when employing the vegetable oil + Argon gas, reached 0.120 mm3/min, and then 0.175 mm3/min. The lowest SR values obtained for all the designed experiments reached 3.287 µm when using Ip (10 A), Ton (1600 µsec), and Ar additive gas, followed by 4.567 µm when adding Freon gases to the dielectric. In the ND-EDM, the average of recast white layer thickness in the case of vegetable oil + air, vegetable oil + Ar, vegetable oil + mix (Ar-N2), and vegetable oil + Freon was 1.505, 1.180, 0.456, and 0 μm, respectively. These unique results can be used to increase the service and fatigue life of parts and machines that are exposed to sudden dynamic mechanical or thermal loads, without the need for additional operations to remove this brittle layer, which causes the failure of these parts with a short service life. The created mathematical models displayed a higher value of R-Square and the adjusted R-square, which manifest a better fit. Normal probability plots of the residuals for MRR, EWR, and SR elucidated an obvious pattern (i.e., the points were stabilized in a straight line) which indicates that every factor affects the mentioned responses and the outcomes of these responses from the regression model (predicted value by factorial) and the true values (from the experiments).
PL
Materia organiczna gleby odgrywa istotną rolę w chemicznych, mikrobiologicznych i fizycznych aspektach żyzności gleby. Odpady organiczne przekształcone w humifikowany materiał organiczny w procesie kompostowania można wykorzystać jako organiczne dodatki zwiększające zawartość materii organicznej i poprawiające żyzność gleby. Jakość kompostu różni się w zależności od rodzaju kompostowanych odpadów i technologii procesu kompostowania i jest bardzo istotna, zwłaszcza jeśli chodzi o optymalną zawartość pierwiastków, takich jak fosfor i azot. Przedstawiono wyniki badań zawartości P i N dla czterech różnych rodzajów kompostów.
EN
Four types of compost (household composts, rural compost processed by poultry and 2 composts from the mech.-biolog. treatment plant of municipal waste) were studied for P and N content. The lowest av. P and N content was recorded in rural compost, 1.6 and 1.5% by mass, resp., and the highest in household compost, 3.2 and 2.7% by mass, resp.
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