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Number of results: 26
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Abstract

During austral summer phytoplankton is the main component of food of E. superba postlarval stages. Diatomeae: Thalassiosira spp., Nitzschia spp. and tiny Pennatae constitue 98% of all consumed food particles. 91% of algae consumed were of 8—40 μm, and their mean size is 21.4 μm. The mean amount of algae found in of Euphausia superba was about 1700 per individual. The differences in species composition and the size of algae eaten by juvenes, preadult and adult individuals decrease the food competition between particular age groups of E. superba.
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Abstract

Porosity is one of the major defects in aluminum castings, which results is a decrease of a mechanical properties. Porosity in aluminum alloys is caused by solidification shrinkage and gas segregation. The final amount of porosity in aluminium castings is mostly influenced by several factors, as amount of hydrogen in molten aluminium alloy, cooling rate, melt temperature, mold material, or solidification interval. This article deals with effect of chemical composition on porosity in Al-Si aluminum alloys. For experiment was used Pure aluminum and four alloys: AlSi6Cu4, AlSi7Mg0, 3, AlSi9Cu1, AlSi10MgCu1.
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Abstract

The use of biomass in the energy industry is the consequence of ongoing efforts to replace Energy from fossil fuels with energy from renewable sources. However, due to the diversity of the biomass, its use as a solid fuel generates waste with diverse and unstable chemical composition. Waste from biomass combustion is a raw material with a very diverse composition, even in the case of using only one type of biomass. The content of individual elements in fly ash from the combustion of biomass ranges from zero to tens of percent. This makes it difficult to determine the optimal recovery methods. The ashes from the combustion of biomass are most commonly used in the production of building materials and agriculture. This article presents the elemental composition of the most commonly used biomass fuels. The results of the analysis of elemental composition of fly ashes from the combustion of forest and agricultural biomass in fluidized bed boilers used in the commercial power industry were presented. These ashes are characterized by a high content of calcium (12.3–19.4%), silicon (1.2–8.3%), potassium (0.05–1.46%), chlorine (1.1–6.1%), and iron (0.8–6.5%). The discussed ashes contained no sodium. Aluminum was found only in one of the five ashes. Manganese, chromium, copper, nickel, lead, zinc, sulfur, bismuth, titanium and zirconium were found in all of the examined ashes. The analysis of elemental composition may allow for a preliminary assessment of the recovery potential of a given ash.
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Abstract

Changes in the amount of basic nitrogen fractions (total, protein and non-protein nitrogen) were studied in an annual cycle. Significant seasonal changes were noted, minima occurring in Antarctic winter and maxima during spring-summer season. These changes are due mainly to high fluctuations of water content in krill in the annual cycle.
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Abstract

Applying the commonly accepted definitions of identity to landscape as our field of research, in particular landscape in protected areas, we assume that identity is the deepest relationship with the landscape (surroundings) perceived by man, with its historical layers of content (the culture and tradition of a place) and form (the canon of a place). An evaluation of change in time should be the keynote of deliberations on place identity. Basing on the current status of research, a review of specialist literature and the author’s experience to date, the above definitions and terms may be referenced to talk about “former” and “new” place identity, especially if we acquiesce to what is termed “the culture of a place” that originates in love for it and willingness to participate in the act of creation that has been launched upon the site. Author tries to explain this fenomenom on example of revitalization, on scale of conntry or even the Europe – the cultural – strategic landscape od Zamość Fortress.
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Abstract

Nematoda, Tardigrada, Rotifera and Crustacea composition in different freshwater habitats on Spitsbergen (Arctic) and King George Island (Antarctic) was presented. In all surveyed groups more genera and species were recorded from Spitsbergen than from King George Island. Habitats richest in taxa were moss banks and thaw ponds, whereas streams were poorest in species. In all groups in both regions cosmopolitan species dominated, but higher number of endemic species was recorded on King George Island. Regarding species composition in surveyed groups it can be suggested that freshwater habitats on Spitsbergen are more similar to each other than those on King George Island.
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Abstract

Changes in body mass and body reserves of Little Auks (Alle alle) were studied throughout the breeding season. Body mass loss after chick hatching was analyzed with respect to two hypotheses: (1) mass loss reflects the stress of reproduction, (2) mass loss is adaptive by reducing power consumption during flight. Body mass of both males and females increased during incubation, dropped abruptly after hatching, and remained stable until the end of the chick-rearing period. These changes were largely due to change in mass of fat reserves. Body mass, fat, and protein reserves, when corrected for body size, did not differ between sexes at the end of incubation. Female size-corrected body mass at that time was correlated with peak body mass of chicks. The estimated energy savings for flight due to the decline in adult body mass after chick hatching were small compared with the total energy expenditure of adults feedings chicks, which did not support hypothesis (2). The contribution to chick feeding was not equal; the ratio of females to males caught with food for chicks was 1.8. Size-corrected body mass during chick-rearing was lower in females, proportional to their higher chick feeding effort compared with males. Females, in contrast to males, lost protein reserves during chick-rearing. Digestive tract mass of adults increased by half throughout the breeding period. These findings supported elements of hypothesis (1). Despite high energy expenditure rates, both sexes had about 10 g of fat reserves at the end of chick feeding. Body mass of both sexes was constant during the greater part of the chick-feeding period. It was suggested therefore that mass loss is regulated with respect to lower fat reserves required during chick-rearing.
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Abstract

The research was carried out on species diversity, density and similarity of Gastrotricha living on two species of macrophytes Myriophyllum spicatum L. and Elodea canadensis Michx. in a mesotrophic lake. Gastrotricha occurring on the studied macrophytes were represented by 23 species (21 on M. spicatum L. and 22 on E. canadensis Michx.). Species diversity (expressed by the Shannon index) for the Gastrotricha occurring on the two studied species of macrophytes amounted to 2.70 for M. spicatum L. and 2.81 for E. canadensis Michx., what suggests equal distribution of the gastrotrich species revealed in the studied species of macrophytes. The definite dominants inhabiting the two species of macrophytes were: Heterolepidoderma macrops Kisielewski, 1981, Heterolepidoderma ocellatum (Mečnikow, 1865), Lepidoderma squamata (Dujardin, 1841) and Aspidiophorus squamulosus Roszczak, 1936, and their inclusive percentage participation in the whole gastrotrich fauna for M. spicatum L. and E. canadensis Michx. was 41.8 and 40.3% respectively. The domination structure of the gastrotrich fauna of the two species of macrophytes was similar for each gastrotrich species (G-test, for all p > 0.05). Average density of Gastrotricha inhabiting M. spicatum L. amounted to 588.0 10³ indiv. m-2, and density of Gastrotricha occurring on E. canadensis Michx. amounted to 670.0 10³ indiv. m-2. Statistic analysis based on the Mann-Whitney test showed that differences of the gastrotrich densi-ty on the studied species of macrophytes: M. spicatum L. and E. canadensis Michx. (Z = -1.9282; p = 0.05) are statistically insignificant.
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Abstract

Carotenoids in six species of the lichens from Antarctica (Xanthoria eleguns, Caloplaca regalis, Usnea antarctica, U. fasciata, Himantormia lugubris and Ramalina terebrata) have been investigated by means of column and thin — layer chromatography. The following carotenoids were found: β-carotene, α- and β-cryptoxanthin, canthaxanthin. lycophyll, lycoxanthin, lutein, lutein epoxide, zeaxanthin, antheroxanthin, adonixanthin, diatoxanthin, rhodoxanthin, rhodoxanthm derivative, α-doradexanthin, astaxanthin, astaxanthin ester, mutatochrome, mutatoxanthin and cryptoflavin. Most frequently occurred β-carotene, β-cryptoxanthin, lutein epoxide, zeaxanthin and mutatoxanthin. The total carotenoid content ranged from 10.242 (Ramalina terebrata) to 18.700 mg/g dry weight (Himantormia lugubris) in October and from 4.765 (Ramalina terebrata) to 12.462 mg/g dry weight (Caloplaca regalis) in February.
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Abstract

Transverse effective thermal conductivity of the random unidirectional fibre-reinforced composite was studied. The geometry was circular with random patterns formed using random sequential addition method. Composite geometries for different volume fraction and fibre radii were generated and their effective thermal conductivities (ETC) were calculated. Influence of fibre-matrix conductivity ratio on composite ETC was investigated for high and low values. Patterns were described by a set of coordination numbers (CN) and correlations between ETC and CN were constructed. The correlations were compared with available formulae presented in literature. Additionally, symmetry of the conductivity tensor for the studied geometries of fibres was analysed.
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Abstract

Physical and chemical properties of Arctic soils and especially the properties of surface horizons of the soils are very important because they are responsible for the rate and character of plant colonization, development of vegetation cover, and influence the rate and depth of thawing of soils and development of active layer of permafrost during summer. The main aim of the present study is to determine and explain the spatial diversity of selected physical and chemical properties of surface horizons of Arctic soils from the non-glaciated Fuglebekken catchment located in the Hornsund area (SW Spitsbergen) by means of geostatistical approach. Results indicate that soil surface horizons in the Fuglebekken catchment are characterized by highly variable physical and chemical properties due to a heterogeneous parent material (marine sediments, moraine, rock debris), tundra vegetation types, and non-uniform influence of seabirds. Soils experiencing the strongest influence of seabird guano have a lower pH than other soils. Soils developed on the lateral moraine of the Hansbreen glacier have the highest pH due to the presence of carbonates in the parent material and a lack or presence of a poorly developed and discontinuous A horizon. The soil surface horizons along the coast of the Hornsund exhibit the highest content of the sand fraction and SiO2. The surface of soils occurring at the foot of the slope of Ariekammen Ridge is characterized by the highest content of silt and clay fractions as well as Al2O3, Fe2O3, and K2O. Soils in the central part of the Fuglebekken catchment are depleted in CaO, MgO, and Na2O in comparison with soils in the other sampling sites, which indicates the highest rate of leaching in this part of the catchment.
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Abstract

An important task for present and future generations is the protection of the national cultural resources. The most attractive architectural objects of historic value include palaces, manors, castles and monasteries. Less attention is paid to educational areas, which apart from the main educational and didactic goal (positive influence on the young person's mind, shaping his personality, social integration) have a great influence on his health, the quality of his life and the shape of his environment. The example of this is the park next to the school complex in Sobieszyn, located in Lublin Voivodeship, Ułęż County. The school complex with its surrounding park established at the end of the 19 th century was given by a will of the Count Kajetan Kanty Kicki, Gozdawa coat of arms, a philantropist and a contemporary owner of Sobieszyn. Localisation of the school, far away from the centre of the village, on the slope of one of the right side tributaries of the Wieprz River – Świnka, makes it an extraordinary place, emphasising the nature values that surround it. Nowadays, the building is still a school- Kajetan Kicki Agriculture School in Sobieszyn.
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Abstract

Although chaetognaths inhabiting polar ecosystems are relatively well known, there are few reports on their functioning in the Antarctic coastal plankton community. The presented results provide the first comprehensive description of population structure of chaetognaths in the neritic zone west of the Antarctic Peninsula. The studies were performed on samples collected in Admiralty Bay, from December 1994 to June 1995. Following six chaetognath species were determined: Eukrohnia hamata, E. bathypelagica, E. fowleri, Pseudosagitta gazellae, P. maxima and Solidosagitta marri. The representatives of Eukrohnia were observed almost throughout the research period, whereas those of Pseudosagitta and Solidosagitta were found only during first four months of our investigation. Eukrohnia hamata showed a strong dominance in respect to abundance (max. 445 ind./1000 m3). The mean abundance of all taxa significantly fluctuated in the study period and across weeks. Generally, all species were represented by the first three maturity stages (I-III), individuals stage IV occurred sporadically, and mature specimens (stage V) were not recorded at all. Morphometric analysis of the most abundant species showed distinct differences in their total length and body proportions. Our findings may suggest that chaetognath populations in Admiralty Bay are migrant, dependent on the inflow of water from the Bransfield Strait, but to prove this statement further, round year study is necessary.
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Abstract

The paper gives coverage to peculiarities of water elements application in landscape compositions created in 19th century by gardener of Dionizy Mikler (Denis McClair) at Volhynia. Being an ambassador of English landscape garden style in this region D. Mikler seamlessly integrated picturesque natural and artificial water components in the garden structure. There are considered the role and ways of interaction of water elements with the landscape compositions by giving examples of Polish landowner´s residences in Gorodok, Mizoch, Mlyniv and Shpaniv.
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Abstract

Humification plays an important role in stabilization of organic matter in soils of the cryolithic zone. In this context, the degree of organic matter stabilization has been assessed, using instrumental methods, for permafrost peat soils of the eastern European Arctic, based on selected plots from within the Komi Republic (Russian Federation). Humic substances (HSs) isolated from the mire permafrost peats of the forest-tundra subzone of the European Arctic have been characterized in terms of molecular composition. This was accomplished using elemental and amino acid fragments (AAFs) composition. Solid-state 13C nuclear magnetic resonance (13C NMR) spectroscopy was utilized to identify the structure of HSs. Changes in the molar x(H) : x(C) ratio, ratio of aromatic to paraffin fragments and ratio of hydroxy AAFs to heterocyclic AAFs along the peat profiles have been revealed. They are due to the activation of cryogenic processes in the upper part of the seasonally thawing layer, the natural selection of condensed humic molecules, the botanical composition and degree of degradation of peat, which reflect the climatic features of the area in the Holocene. Humic acids and fulvic acids of the peat soils showed the prevalence of compounds with a low degree of condensation and a low portion of aromatic fragments. The aromaticity degree showed the trend to increase within the depth. Changes of quantitative and qualitative parameters of specific organic compounds occur at the permafrost boundary of peatlands, which can serve as an indicator of recent climate changes in environments from the high latitudes. The presented data can be useful in the evaluation of soil organic matter stabilization degree in the active layer and below the permafrost table.
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Abstract

The site at Orłowo Cliff was used to analyse the stratigraphic position and palaeogeographic interpretations of the properties and depositional conditions of two basal tills from the Late Pleistocene. A multi-proxy approach involved lithofacies, petrographic analysis of the fine gravel fraction, analyses of indicator erratics and till fabric. TL dating of intra-moraine deposits was used to determine depositional time frames of tills. The sediment profile at Orłowo Cliff shows a distinct reduction in number of Pleistocene units. Obtained dating results suggest the presence of Middle and Late Pleistocene fluvial units. The main issue discussed is the stratigraphic position of the older till (Unit O-4). It can be assumed that this till was deposited probably during the Middle Weichselian (MIS4). At Orłowo Horn the till of Unit O-4 reveals incorporation of the erratic material derived from an older till in the surrounded area (according to petrographic composition – probably from MIS 8). The younger till (Unit O-6) was deposited in the Late Weichselian (MIS 2). Moreover, the till of Unit O-6 is characterised by a significant shift towards the south-west in terms of the erratic origin in Unit O-4.
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Abstract

The aim of the study was to determine the effect of adding bio-components in the form of methyl esters of corn oil to the milesPLUS diesel oil on its fractional composition. The corn biofuel was produced in-house by using an own-design GW-200 reactor. The diesel fuel evaporated at temperatures ranging from 162 to 352oC. The addition of 7, 20 and 40% of a bio-component in principle does not affect the deterioration of the starting point distillation temperatures. They affect the temperature at the end of distillation to a greater extent, resulting in temperatures exceeding 360oC.
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Abstract

This paper presents a study of the seismic P−wave velocity and density structure of the lithosphere−asthenosphere system along a 800 km long transect extending from the actively spreading Knipovich Ridge, across southern Spitsbergen to the Kong Karls Land Volcanic Province. The 2D seismic and density model documents 6–8 km thick oceanic crust formed at the Knipovich Ridge, a distinct continent−ocean−boundary (COB), the eastern boundary of the dominantly sheared Hornsund Fault Zone, and the eastern boundary of the Early Cenozoic West Spitsbergen Fold−and−Thrust Belt. The crustal continent−ocean transitional zone has significant excess of density (more than 0.1 g/cm 3 in average), characteristic for mafic/ultramafic and high−grade metamorphic rocks. The main Caledonian suture zone between Laurentia and Barentsia is interpreted based on variations in crustal thickness, velocities and densities. A high velocity body in the lower crust is preferably interpreted in terms of Early Cretaceous magmatism channelled from an Arctic source southwards along the proto−Hornsund zone of weakness. The continental upper mantle expresses high velocities (8.24 km/s) and densities (3.2 g/cm 3 ), which may be interpreted in terms of low heat−flow and composition dominated by dunites. The lower velocities (7.85 km/s) and densities (3.1 g/cm 3 ) observed in the oceanic lithosphere suggest composition dominated by primitive peridotites. The model of mantle allows for successful direct description of subcrustal masses distribution compensating isostatically uneven crustal load. The estimated low value of correlation between density and velocity in the mantle 0.12 kg × s × m −4 suggests that horizontal density differences between oceanic and continental mantle would be dominated by compositional changes.
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Abstract

Cast stainless steel of the Cr-Ni duplex type is used, among others, for the cast parts of pumps and valves handling various chemically aggressive media. Therefore, the main problem discussed in this article is the problem of abrasion wear resistance in a mixture of SiC and water and resistance to electrochemical corrosion in a 3% NaCl- H2O solution of selected cast steel grades, i.e. typical duplex cast steel, high silicon and manganese duplex cast steel, and Cr-Ni austenitic cast steel (type AISI 316L). The study shows that the best abrasion wear resistance comparable to Ni-Hart cast iron was obtained in the cast duplex steel, where Ni was partially replaced with Mn and N. This cast steel was also characterized by the highest hardness and matrix microhardness among all the tested cast steel grades. The best resistance to electrochemical corrosion in 3% NaCl- H2O solution showed the cast duplex steel with high content of Cr, Mo and N. The addition of Ni plays rather insignificant role in the improvement of corrosion resistance of the materials tested.
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Abstract

In the article we were studing the impact of the remelting on transformations in Co-Cr-Mo prosthetics alloy. The TDA curves were analyzed, the microstructure was examined, the analysis of the chemical composition and hardness using the Brinell method was made. It was found that the obtained microstructure of the alloys that we studied do not differ significantly. In all four samples, microscopic images were similar to each other. The volume, size and distribution of the phases remain similar. Analysis of the chemical composition showed that all the samples fall within the compositions provided for the test alloy. Further to this the hardness of the samples, regardless of the number of remeltings did not show any significant fluctuations and remained within the error limit.After analyzing all the results, it can be concluded that the remeltings of the alloys should not have a significant impact on their properties. Secondarily melted alloys can be used for prosthetics works.
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Abstract

Blast furnace and cupola furnace are furnace aggregates used for pig iron and cast iron production. Both furnace aggregates work on very similar principles: they use coke as the fuel, charge goes from the top to down, the gases flow against it, etc. Their construction is very similar (cupola furnace is usually much smaller) and the structures of pig iron and cast iron are very similar too. Small differences between cast iron and pig iron are only in carbon and silicon content. The slags from blast furnace and cupola furnace are very similar in chemical composition, but blast furnace slag has a very widespread use in civil engineering, primarily in road construction, concrete and cement production, and in other industries, but the cupola furnace slag utilization is minimal. The contribution analyzes identical and different properties of both kinds of slags, and attempts to explain the differences in their uses. They are compared by the contribution of the blast furnace slag cooled in water and on air, and cupola furnace slag cooled on air and granulated in water. Their chemical composition, basicity, hydraulicity, melting temperature and surface were compared to explain the differences in their utilization.
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Abstract

The aim of the studies was to evaluate the influence of sowing rate, foliar fertilization (Basfoliar fertilizer 6-12-6) and chemical composition on the mechanical properties of narrow- leaved lupine seeds of cultivars Bojar and Regent. Single seeds were burdened in the direction perpendicular to the parting plane of cotyledons with constant speed 10 mm∙min-1. The crop year and cultivar have significantly differentiated the value of all the analyzed strength parameters of narrow-leaved lupine seeds. The seeds of cultivar Bojar had significantly higher values of all the strength parameters. The designated strength parameters of lupine seeds were negatively correlated with ash content, fiber and protein except for the destructive force. They were also positively correlated with the fat content.
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Abstract

The surface properties of particles emitted from six selected coal-fired power and heating plants in Poland have been studied in this work for the first time. Samples were collected beyond the control systems. Surface composition of the size-distributed particles was obtained by photoelectron spectroscopy (XPS). The reflection of the smallest, submicron particles was also measured to calculate their specific/mass absorption. The surface layer of the emitted particles was clearly dominated by oxygen, followed by silicon and carbon. The sum of the relative concentration of these elements was between 85.1% and 91.1% for coarse particles and 71.8–93.4% for fine/submicron particles. Aluminum was typically the fourth or fifth, or at least the sixth most common element. The mass absorption of the submicron particles emitted from the studied plants ranged from 0.02 m2g-1 to 0.03 m2g-1. Only specific absorption obtained for the “Nowy Wirek” heating plant was significantly higher than in other studied plants probably because the obsolete fire grate is used in this heating plant. The obtained results suggest that the power/heating-plant-emitted fine particles contain less carbonaceous material/elemental carbon on their surfaces than those that are typical in urban air.
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