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1
EN
Gas carriers are one of the most advanced types of ships and are equipped with the latest technological achievements. Due to the development of this industry, the demand for ethylene transport by sea has increased significantly in recent years. Nonetheless, it is one of the most problematic loads in terms of loading operations. Due to the small density differences between ethylene and nitrogen, ethylene is one of the most problematic hydrocarbons with respect to the efficient gasification of cargo tanks. Additionally, ethylene is one of the most expensive cargoes carried on gas carriers. The above aspects make it necessary to carry out a detailed analysis of the flushing of nitrogen-loaded cargo tanks with ethylene vapors to determine the range of technical parameters to enable more efficient tank gassing-up. This paper provides a detailed analysis of an experimental cargo tank gassing-up operation on an ethylene carrier. The process was carried out in accordance with previously-determined assumptions to optimize the discussed operations, assess how the cargo tank pressure influences this process, reduce cargo loss during gassing-up, and eliminate cargo loss during its cooling. The conclusions from this experiment provide guidelines for subsequent tests.
2
Content available remote Efektywność nawożenia i wykorzystania azotu przez pszenżyto ozime
PL
Przeprowadzono doświadczenie polowe z odmianami pszenżyta ozimego w celu określenia wskaźników wykorzystania azotu z nawozów w zależności od dawki azotu i sposobu uprawy gleby. Badania wykazały zmniejszenie efektywności fizjologicznej przy wzroście nawożenia azotem z 90 do 120 kg/ha. Efektywność rolnicza nie różniła się istotnie. Duże wykorzystanie azotu z nawozów i istotnie wyższy plon ziarna odnotowano dla obiektu, w którym azot stosowano w dawce 90 kg/ha, przy uprawie płużnej oraz u odmiany mieszańcowej.
EN
Four varieties of winter triticale (Meloman, Trapero, Rotondo and hybrid BOH 2415) were cultivated on wheat soils by using different doses of N fertilizers (0-120 kg/ha) in traditional (plow) and simplified (without plowing) cultivation systems. The indicators of N consumption from fertilizers were examd. by detn. of N content in grain and straw. High N utilization from fertilizers and significantly higher yields were recorded in the case of N fertilization at a dose of 90 kg/ha in plow cultivation and for hybrid BOH 2415 cultivar. A physiol. efficiency decreased with the increase of N fertilization from 90 to 120 kg/ha, while the agricultural efficiency did not differ significantly.
EN
Phytoplankton structure was studied in five ponds (located in the Oleksandriya Nature Park, Ukraine), which significantly differed in the level of their contamination. The concentration of ammonium (NH4+-N) in the studied water bodies was 0.02–74.00 mg l-1, of nitrite (NO2--N) – 0.002–1.750 mg l-1, nitrate (NO3--N) – 0.13–58.00 mg l-1, inorganic compounds of phosphorus (Pinorg) – 0.041–0.160 mg l-1, chloride (Cl–) – 35.4–560.5 mg l-1, whereas the content of organic matter (PO and DO) – 4.4–10.4 and 18.0–81.0 mg O l-1, respectively. It has been found that the response of phytoplankton to heavy pollution consisted in changes in its species richness, taxonomic structure, species composition, quantitative indices, numbers and biomass structure, dimensional structure, pigment index, dominant complex, as well as changes in its ecological spectrum. Individual divisions of algae differed in their response to heavy pollution of water bodies, which was conditioned by the specificity of algae metabolism. Bacillariophyta and Cyanoprokaryota proved to be more sensitive to contamination, whereas Chlorophyta and Euglenophyta – more tolerant. The obtained data can be used to monitor the status of water bodies and their biota and to determine the type and intensity of contamination.
EN
In this study, we collected submarine groundwater discharge (SGD) and seawater samples at six sites in the Bay of Puck, in the southern Baltic Sea, in order to estimate the nutrient distribution in groundwater affected areas. In addition, we estimated nutrient fluxes via SGD, including both fresh SGD (FSGD) and recirculated seawater SGD (RSGD), to the entire Bay of Puck. Phosphate (PO43−) concentrations varied significantly among study sites and seasons, while both ammonium (NH4+) and nitrates (NO3−) concentrations varied only seasonally. The N:P ratio indicated P limitation in most of the samples. The estimated seasonal and annual loads, via SGD, of both dissolved inorganic nitrogen (DIN; 9303 t yr−1) and PO43− (950 t yr−1), were the most significant source of nutrients to the Bay of Puck, and notably higher than quantified before (FSGD nutrient loads of 50 t yr−1 and 56 t yr−1 for DIN and PO43−, respectively). The SGD fluxes reported here indicate some of the highest rates of sediment-water fluxes reported in the Baltic Sea. These results suggest that SGD (both FSGD and RSGD) should be considered as source of chemical substances to the marine environment.
EN
The study presents the results of 3-year field experiments aimed at assessing the effect of nitrogen dose balanced on the basis of Nmin content, depending on the distribution in the soil profile and recognizing the effect of the type of nitrogen fertilizer on the formation of maize grain yield components. Nitrogen applied in the form of mineral fertilizer was characterized by greater efficiency in comparison to Nmin contained in the soil, as evidenced by a significantly higher grain number in the ear and 1000 grain weight. It was shown that mineral nitrogen (Nmin) present in soil in maize rooting zone significantly influenced the number of production ears per area unit. Inclusion of the pool of the component contained in the soil in the algorithm for calculating nitrogen dose significantly improves the quantitative status of the ears. It is sufficient to collect soil samples from two levels, i.e., 0-30 cm and 0-60 cm, to determine nitrogen dose based on the soil abundance in mineral nitrogen (Nmin).
PL
Przedstawiono wyniki trzyletnich badań polowych, których celem była ocena wpływu wielkości dawki azotu bilansowanej w oparciu o zawartość Nmin, zależnie od rozmieszczenia w profilu glebowym oraz rozpoznanie wpływu rodzaju nawozu azotowego na kształtowanie komponentów plonu ziarna kukurydzy. Azot zastosowany w formie nawozu mineralnego w porównaniu do azotu Nmin zawartego w glebie charakteryzował się większą efektywnością, o czym świadczyła istotnie większa liczba ziaren w kolbie oraz masa 1000 ziaren. Wykazano, że azot mineralny (Nmin) zawarty w glebie w strefie ukorzeniania się kukurydzy istotnie kształtuje liczbę kolb produkcyjnych na jednostce powierzchni. Uwzględnienie w algorytmie wyliczenia dawki azotu puli składnika zawartego w glebie istotnie poprawia stan ilościowy kolb. W celu wyznaczenia dawki azotu w oparciu o zasobność gleby w azot mineralny (Nmin) wystarczy pobrać próby glebowe z dwóch poziomów, tzn. 0-30 cm i 0-60 cm.
EN
Erosion strongly influences the soil properties and affects the intra-field variation of nutrients not only in steep young morainic landscapes but also on gentle slopes of old-glacial landscapes. The aim of the study was the evaluation of changes in the plant-available nutrient contents in the complex old-glacial eroded landscape of the Bielska Plain in the north-eastern part of Poland. The soil samples were collected from the soil profiles located along the transect beginning on the flat summit of the kame hummock extending through south-facing convex slope, the toeslope and footslope and further through the north-facing uniform slope. The content of plant-available forms of phosphorus (Pdl) and potassium (Kdl) and mineral forms of nitrogen (NH4-N and NO3-N) were determined in every soil profile. The soils located in various landscape positions were characterized with different fertility. In the soil located on the toeslope the content of NO3-N, Pdl and Kdl was high, while the soil located on the summit was rich in NH4-N and poor in the plant-available forms of K and P. The erosional distribution of plant-available N, P and K enhances the variation of nutrient content within one field and contributes to high variability of crops.
EN
The work demonstrates the suppression of the inhibiting effect of the carbon dioxide absorption process by chlorophyll-synthesizing Chlorella microalgae due to sulfur oxide SO2, activators of phosphorus oxide P2O5 and nitrogen oxides NxOy The research presents the experimental dependences of the dynamics of СО2 absorption by microalgae under the critical concentration of inhibitor SO2 in the presence of the P2O5 and NxOy activators. The authors devised the mathematic models of growth of the Chlorella microalgae population depending on the concentration of the phosphorus oxide and nitrogen oxides activators under a permanent concentration of the sulfur oxide inhibitor. The research determined an optimal total concentration of P2O5 activator in the presence of the SO2 inhibitor, as well as an optimal total concentration of the NO2 activator in the presence of the SO2 inhibitor.
EN
The main objective of this investigation was to evaluate the efficiency of electrocoagulation in eliminating nitrogen and phosphorous from domestic wastewater and to determine the main operating parameters affecting the process. Accordingly, an acrylic reactor and aluminum (cathode) and iron (anode) electrodes were used. The tests were performed based on a multilevel factorial experimental design, considering current intensity, treatment time, and pH as factors. The design response variables were the percentage of nitrogen and phosphorous removal. In the case of phosphorus, the removal rates of up to 99% were reached after 40 minutes of treatment with current intensities of 3 amps and at a modified pH of 6. The nitrogen removal was up to 27% with a treatment time of 40 minutes, 3 amps, and a pH of 6. A statistical analysis revealed that pH did not have a significant effect on the nitrogen removal process, whereas in the phosphorus removal, the three factors influenced the process at a confidence level of 0.05. The results indicate that the electrocoagulation process in this type of water is very efficient in the removal of phosphorus, whereas for nitrogen, the efficiency decreases noticeably. However, electrocoagulation has an advantage over other conventional treatment technologies, because it does not require additional treatment units to remove phosphorus.
EN
The aim of the study was to evaluate the changes in the carbon/nitrogen ratio as a result of different natural methods of sewage sludge treatment from two municipal wastewater treatment plants. The sludge from the first treatment plant was poured into two lagoons, one covered with reed and the other with willow and a field with Californian earthworms. The sludge from the second treatment plant was composted with sawdust. The sludge processed with each method was simultaneously subjected to Effective Microorganisms. The samples of processed sludge from both treatment plants were collected three times. In the first one, after five weeks, four months and ten months from the beginning of treatment. The material from the second treatment plant was composted after four, ten weeks and a year of composting. In the samples taken, the total nitrogen content was determined by means of the Kjeldahl method. The determination of the organic carbon content was carried out on a TOC analyser. The C:N ratio was then calculated. It was found that the changes in the C:N ratio depended on the duration of individual processes, and to a lesser extent on the way they were processed. The carbon content during sludge processing increased or remained at a similar level and the nitrogen content decreased with time of their processing, regardless of the EM addition. The addition of Effective Microorganisms to the sludge treatment reduced the C:N ratio in the first period of time and increased this ratio to the optimal value after 10 months or a year. The best technology for sludge processing appeared to be the technology of heap composting with sawdust and with aeration. The ten-week compost had a suitable C/N ratio for use in lawn production.
PL
W artykule opisano nowo stosowaną w Narodowym Centrum Badań Jądrowych technologię odgazowania miedzi do potrzeb wysokiej próżni. Wysoka próżnia jest wymagana, w celu zapewnienia skutecznego przyspieszania elektronów w akceleratorach. Etapem osiągnięcia wystarczająco wysokiej próżni w strukturze jest odgazowanie termiczne wnętrza miedzianych wnęk rezonansowych, które stykają się z próżnią. Dotychczasowy proces odgazowania opierał się na prowadzeniu odgazowania wnętrza rezonatorów poprzez grzanie zewnętrznej powierzchni struktury w pomieszczeniu laboratorium. Nowa technologia polega na prowadzeniu procesu odgazowania w ograniczonej, izolowanej termicznie przestrzeni.
EN
The article describes the newly used bake-out technology for copper to meet the needs of high vacuum. High vacuum is required to ensure effective acceleration of electrons in accelerators. The stage of achieving a sufficiently high vacuum in the structure is bake-out of the interior of the copper resonant cavities that are in contact with the vacuum. The previous bake-out process was done by heating the outer surface of the structure in the laboratory. The new technology is conducted by a bake-out process in a limited, thermally insulated space.
11
EN
High effectiveness of organic pollutants and nutrients removal is achieved in biological wastewater treatments plants – in case of proper exploitation of these objects. Nitrogen and phosphorus transformation or removal depends on many physic – chemical and biochemical conditions, deposit and environmental factors. A rule for treating wastewater consists in decomposition of organic compounds included in wastewater in water-soil environment. Removing contaminations is performed as a result of sorption of contaminations, bio-chemical oxidation-reduction reactions and biological activity of soil microorganisms and hydrophyte flora. The research has been carried out in the constructed wetland in Małyszyn (1300 EP). The treatment plant operates in horizontal system, with under-surface flow of wastewater.
PL
Badania prowadzono na jeziorze Bartąg (powierzchnia 72,3 ha, max. głębokość 15,2 m) pod Olsztynem. Zlewnia jeziora ma powierzchnię 400,3 ha, w której największy udział mają grunty orne – 68,9%, lasy zajmują 19,7%, a teren zabudowany – 11,4%. W wodach jeziora stwierdzono jednostkowe i duże ilości biogenów, sięgające 1,24 mg Pog∙dm–3 i 2,35 mg Nog∙dm–3 oraz wapnia – 61,0 mg Ca∙dm–3. Przyczyną dużej trofii tego zbiornika jest nadmierne jego obciążenie biogenami spływającymi ze zlewni. Rzeczywiste ładunki biogenów spływające do jeziora przekraczają wartości krytyczne obliczone wg Vollenweidera. Niska jakość wód tego jeziora, z jednoczesnym dużym obciążeniem ładunkiem zanieczyszczeń, ze zlewni wskazuje na konieczność podjęcia działań ochronnych, polegających na zmniejszeniu obciążenia zewnętrznego.
EN
The study was carried out on Lake Bartąg (area 72.3 ha, maximum depth 15.2 m) near Olsztyn. The catchment area of the lake is 400.3 ha, in which arable land cover the largest share – 68.9%, forests occupy 19.7%, and built-up area – 11.4%. In the lake's waters, unitary and large amounts of nutrients were found, reaching 1.24 mg TP∙dm–3 and 2.35 mg TN∙dm–3 and calcium – 61.0 mg Ca∙dm–3. The reason for the high trophic status of this reservoir is its excessive load on biogenes flowing from the drainage basin. The actual loads of nutrients flowing into the lake exceed the critical values calculated according to Vollenweider. The low quality of the lake's waters, with a heavy load of pollutants, from the catchment points to the need to take protective measures, which consist in reducing the external load.
PL
Wykorzystano dane literaturowe dotyczące plonów rożnika przerośniętego w 3 miejscowościach położonych w południowym Chile. Zastosowano oprogramowanie komputerowe do określenia wpływu dawek azotu na plony upraw, na plon maksymalny oraz na plon znormalizowany w odniesieniu do plonu maksymalnego.
EN
Literature data on the cultivation of the tested plant in 3 cities located in the southern Chile and computer software were used to det. an effect of N dose on yields of its crops, on maximal yield as well as on normalized yields in relation to the max. yield.
PL
Opracowano polimorficzny model reaktora biologicznego z logiczną reprezentacją wiedzy o obiekcie sterowania i sterowaniu, dla których proces uczenia się polega na sukcesywnej walidacji i uaktualnianiu wiedzy oraz wykorzystywaniu wyników tego uaktualniania do wyznaczania decyzji sterujących. Na podstawie ciągłego pomiaru stężenia fosforu (jako PO4-P) określono ładunki fosforu jako iloczyn przepływu i stężenia. Różnicę pomiędzy fosforem całkowitym a PO4-P określono empirycznie zgodnie z klasyczną analityką. Zastosowany system sterowania, poza efektem energetycznym, pozwalał również na optymalizację.
EN
An advanced model for the optimization of the title processes was developed by using a multi-threaded predictive control system. The activated sludge method was used in 2 biol. reactors, where denitrification and nitrification and removal of org. C compds. and dephosphatation took place. A sewage aeration and movement in bioreactors was generated by using agitators or sludge recirculation. The computer model of the wastewater treatment plant was developed in a com. environment. An activated sludge model was used to model biochem. processes, including org. C and N removal and transformations involving bacteria using the ability to store P in cell biomass. Then, quantitative and qualitative parameters were identified and the model was calibrated by det. the agreement of simulation results with measured data.
PL
Przeprowadzono analizę i ocenę możliwości wytwarzania nawozów organicznych z makroglonów pozyskiwanych z rejonów Morza Czarnego o podwyższonej antropopresji. Do badań wykorzystano glony Cystozeira barbata pobrane z 3 punktów badawczych zlokalizowanych w rejonie Warny oraz 3 punktów zlokalizowanych w rejonie Burgas. W biomasie oznaczono zawartość makroelementów, mikroelementów oraz metali ciężkich. Na podstawie składu chemicznego oszacowano przydatność badanych materiałów do produkcji nawozów organicznych. W glonach stwierdzono bardzo duże zawartości azotu, potasu i wapnia. Przy ich aplikacji w ilości ok. 3 Mg/ha wprowadzono by do gleby ok. 90 kg azotu, 150 kg wapnia i 50 kg potasu.
EN
Samples of algae taken from the sea water near urban areas as well as rural areas were mineralized at 450°C and treated with HNOз soln. to det. their elemental compn. The place of sampling did not affect on their chem. compn. High content of N, K and Ca and low content of heavy metals in the tested samples indicated their usefulness in agriculture as fertilizers.
EN
The paper presents the results of a multivariable research regarding the evaluation of variability of selected quantitative traits in two cultivars of maize (Zea mays L.): ES Palazzo and ES Paroli after using doses of nitrogen and magnesium. The study took into account 12 traits recorded for three years (2009-2011). The statistical analysis of obtained results was conducted using multivariable methods: multivariate analysis of variance, canonical variable analysis and Mahalanobis distances. The most varied objects were A4B1C2 and A1B2C1 (in 2009), A4B1C1 and A2B2C2 (in 2010), A4B2C1 and A1B2C2 (in 2011) and A4B2C1 and A1B2C2 (for all three years). The most similar objects (with regard to the 12 traits analyzed together) were A4B2C2 and A3B2C2 (in 2009), A4B2C2 and A3B1C2 (in 2010), A2B2C2 and A2B1C2 (in 2011) and A4B2C2 and A3B2C2 (for all three years). The Mahalanobis distances between particular objects in particular years of observations were positive and statistically significantly correlated.
PL
W pracy przedstawiono wyniki badania zmienności wybranych cech ilościowych dwóch odmian kukurydzy (Zea mays L.): ES Palazzo i ES Paroli po zastosowaniu różnych dawek azotu i magnezu stosując wielowymiarowe metody statystyczne. W badaniach wzięto pod uwagę 12 cech ilościowych obserwowanych w doświadczeniu trzyletnim przeprowadzonym w latach 2009-2011. Analiza statystyczna uzyskanych wyników została przeprowadzona z użyciem metod wielowymiarowych: wielozmiennej analizy wariancji, analizy zmiennych kanonicznych i odległości Mahalanobisa. Najbardziej zróżnicowanymi obiektami były A4B1C2 i A1B2C1 (w 2009), A4B1C1 i A2B2C2 (w 2010), A4B2C1 i A1B2C2 (w 2011) oraz A4B2C1 i A1B2C2 (dla wszystkich trzech lat). Natomiast, najbardziej podobnymi obiektami (pod względem wszystkich 12 cech traktowanych łącznie) były A4B2C2 i A3B2C2 (w 2009), A4B2C2 i A3B1C2 (w 2010), A2B2C2 i A2B1C2 (w 2011) oraz A4B2C2 i A3B2C2 (dla trzech lat). Odległości Mahalanobisa pomiędzy poszczególnymi obiektami w poszczególnych latach prowadzenia obserwacji były dodatnio i istotnie statystycznie skorelowane. Słowa
17
EN
A buffer zone is a belt of shelter or permanent grassland separating the agricultural land from watercourses and water reservoirs. According to the Code of Good Agricultural Practices, they constitute a landscape element that can limit the migration of biogenic substances. Increasing attention is paid to the fact that these barriers are effective during the growing season. However, in the autumn-winter and early-spring half-year, they can be a source of nitrogen compounds leached from the catchment to the surface water. In connection with this, research was undertaken to assess the content of nitrogen compounds in the soil of the zone at the channel and water of the watercourse in a small agricultural catchment. The processes occurring in the buffer zones leading to the release of biogenic compounds do not only concern leaching them to surface and groundwater; therefore, the amount of nitrous oxide emissions, which is the result of the denitrification process occurring in the soil, was examined. On the basis of the obtained results, it was found that an increased content of nitrogen compounds in the soil of buffer zones may have an impact on the elevated emission of N2O and a raised content of these substances in surface water.
EN
The tendency to increase the carrying capacity of the electric load in the supply networks can be done in two directions, namely: • the construction of several transmission and distribution lines linking the energy source to the consumer (current trend), having the effect of damaging the environment, or • limiting the construction of transport lines and, implicitly, the destruction of the environment by using technologies and materials capable of carrying a very large amount of electricity.
PL
Tendencja do zwiększania obciążenia elektrycznego w sieciach zasilających może być realizowana w dwóch kierunkach, a mianowicie: budowa kilku linii przesyłowych i dystrybucyjnych łączących źródło energii z konsumentem (obecny trend), powodujących uszkodzenie środowiska, lub ograniczenie budowy linii transportowych i w efekcie ograniczenia zniszczenia środowiska poprzez zastosowanie technologii i urządzeń zdolnych do przenoszenia bardzo dużej ilości energii elektrycznej.
EN
The aim of the three-year pot experiment was to determine the effect of standard mineral fertilization enriched with sulfur and iron on the content of nitrogen and sulfur in plants and on nutrient utilization by plants. Abundance of sulfates in soil after sulfur fertilization was also assessed. The direct effect of fertilization was assessed during the first and second year of the pot experiment, and the after-effect was analyzed during the third year. Rape (first year) and maize (second and third year) were the test plants. Solid mineral fertilizers (A: a mixture of ammonium nitrate and dolomite; B: a mixture of ammonium nitrate and sulfate) enriched with iron sulfate were used. Nitrogen content in the plants varied depending on applied fertilization as well on plant species and part. Sulfur application increased sulfur content in the aboveground parts of plants by 25-457% and in roots by 95-708%. Iron application ambiguously influenced nitrogen and sulfur content in the plants. Hovewer, simultaneous application of iron and sulfur (as fertilizer B enriched with iron) resulted in the highest coefficient of nitrogen (84%) and sulfur (39%) utilization. Sulfur fertilization caused a 5-20 fold increase in sulfate sulfur content in the soil.
PL
Poddano analizie wpływ warunków topnienia metodą TIG w atmosferach Ar+2%N2 i Ar+2%N2+0,2%O2 oraz zawartości tlenu w spoiwach na kinetykę absorpcji azotu przez spoiwa typu Fe-C-Mn. Proces badano w połączeniu z innymi zjawiskami występującymi w stopionych spoiwach. Absorpcja azotu przez topione łukowo spoiwa typu Fe-C-Mn została opisana kinetyczna reakcja I rzędu, dzieląca całkowitą powierzchnię stopionej próbki na obszar oddziaływania łuku elektrycznego i obszar kontaktu z chłodniejszym gazem osłonowym. Na podstawie tego modelu wyznaczono zależne od czasu zmiany zawartości azotu, a także współczynniki transportu masy i szybkości absorpcji azotu w różnych warunkach topnienia. Wykazano, że warunki absorpcji azotu przez topione łukowo spoiwa typu Fe-C-Mn różnią się znacznie od mechanizmu sugerowanego dla czystego Fe i rozwiązań w systemie Fe-O. Reakcja odtleniania węglem zachodząca w wysokich temperaturach jest czynnikiem ograniczającym absorpcje azotu przez topione łukowo spoiwa typu Fe-C-Mn. Wzrost szybkości absorpcji azotu i zawartości azotu, wynikający ze zmniejszenia prądu topnienia, związany jest ze zmniejszeniem intensywności odtleniania węglem i intensywności parowania manganu, a także z powstawaniem ciekłych tlenków, które zmniejszają desorpcję azotu z obszarów niepoddanych oddziaływaniu łuku elektrycznego.
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