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Number of results: 18
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Abstract

Sapropel deposits are widely distributed around the globe. In the Americas area they are adjacent to the Great Lakes region, in Europe sapropel deposits can be spotted in the territory of Scandinavia, France, Switzerland, Germany, Poland, Belarus, Russia and in the northern regions of Ukraine. Use of sapropel as a fertilizer can enhance high and stable yields of crops. However, despite the proven effectiveness of long-term practical researches in this area, nowadays sapropel is almost not used. One of the reasons - lack of developed processing methods of extraction and processing, including dehydration. Material properties as an object of interaction with the working bodies, change of their settings in the processing are crucial in the choice of technologies, development, bringing up to the necessary parameters and subsequent use. Sapropel high humidity (95-98%) is one of the main factor that determines the quality of its properties after the interaction with working bodies. However, in the process of decreasing, in interaction with oxygen, there are significant changes in physical and mechanical properties of sapropel. Decisive in the direction selection process of lake sapropels’ use in the economic sector is their moisture exchange and thermodynamic parameters. The complexity of setting the water apart, if freshly extracted sapropels possess only 15-20% of it, shows their strong water-retaining capacity. The above mentioned phenomenon proves the need for their use as an organic fertilizer during the crops growing, as superficial loss of moisture in the soil creates a new global problem. On the basis of deep analysis of the sapropels’ properties, the authors suggest three areas of freshly extracted lake sapropel application in mixtures with leafy part of the crops: in biogas production with its further use as an organic fertilizer; making a compost mixture of organic origin which physical and mechanical properties are approximate as that of the soil; alternative solid fuels in the form of briquettes.
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Abstract

In 2018 we celebrate the 250th anniversary of the Jędrzej Śniadecki’s birth. This work aims to show the importance of his thoughts for the development of natural sciences. He studied at some of the largest universities in Europe, where he met great scientists of the Enlightenment. The effects can be seen in his works. He was remembered as a founder of Polish biochemistry, anthropology and pathology, also as the author of chemical terminology and language. The essence of his thoughts is Theory of organic being, which is an attempt to answer the question: „what is life?”. Jędrzej Śniadecki introduced a new definition of life based on the term „organic power”. This work shows how import are the thoughts of Jędrzej Śniadecki in the context of the times in which he lived, as well as the following development of natural sciences, what makes him and his theories worth memory.
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Abstract

Water samples were collected at 12 oceanographic stations from six standard depths ranging from 0 to 100 and 150 m. The number of bacteria and concentration of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under I m2 of sea of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under 1 m2 of sea surface. Total numbers of bacteria (TC) ranged from 0.16 to 7.31 x 107/1 and 1.74 — 5.67 x 10, 2/m2 saprophytic bacteria (CFU) 0.10 — 46.85 x 103/1 and 0.62 — 27.7x 108/m2. contents of particulate organic carbon (РОС) 0.02 — 0.25 mg/1 and 3.5 — 20.0 g/m2 dissolved organic carbon (DOC) 0.07 — 3.02 mg/1 and 53.5 — 207.9 g/m2, dissolved free amino acids (DFAA) 0 — 1.8965 μmol/1 and 2.7 -151.5 mmol/m2, dissolved combined amino acids (DCAA) 0 2.9366 μmо1/1 and 16.5— 163.5 mmol/m2, particulate combined amino acids (PCAA) 0 — 3.0215 μmо1/1 and 3.7 — 249.0 mmol/m2. Total numbers of bacteria and РОС, DOC and DCAA concentrations, widely differentiated in the investigated area, were on the average much lower than the values obtaine in previous years. The saprophytic bacteria content and DFAA and PCAA concentrations were at a similar level to that in the past years. Higher TC and CFU values were observed in the areas with high concentrations of phytoioplankton to the NW of Anvers I. and around Clarence I.
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Abstract

Research on the chemistry of atmospheric precipitation in the Hornsund region of Svalbard has been extended by analysis of the organic contents. In rainfall samples collected in September 2003, the organics were separated by solid phase extraction (SPE), eluted and analysed on gas chromatograph coupled to a mass selective detector (GC/MS). Rainfall pH was in the range 4.72–5.45, the low values suggesting possible pollution. Concentrations of inorganic ions, expressed as total dissolved salts (TDS), were 5.40–13.18 mg L–1. Non-sea-salt (nss) sulphates were in the range 5–11 μeq L–1. In all samples, long-chain alkanes with chain length up to C36, and their methyl derivatives were detected. Among aromatic compounds biphenyl, dibenzofuran and its methyl derivatives were found. Polycyclic aromatic hydrocarbons (PAHs) were represented by naphthalene, phenanthrene, fluorene, acenaphthene, fluoranthene and pyrene. There were no PAHs with higher numbers of rings. The synoptic meteorological conditions in September 2003 indicate that all organic and inorganic pollutants were of local origin.
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Abstract

The subject discussed in this paper is the evolution of the ideas of organic development in urban planning, focused on the waterfront areas. The paper also aims to analyze and interpret current trends in urban water waterfront planning, which are infl uenced by the contemporary ideas related to environmental issues, landscape planning, new technologies in the fi eld of building design and civil- and hydroengineering or application of the renewable energy sources.
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Abstract

The analysis of the fractal dimension becomes one of the new approach features in spatial research. This approach bases on the perception of space as a living structure, an organism which in its complexity and heterogeneity is a multi-scale creation although holistically perceived. The aim of the authors was to determine the nationwide fractal dimensions for the distinguished construction categories and designation of general regularities in these layout.
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Abstract

51 samples from the Middle Triassic black shales (organic carbon−rich silt− stones; up to 4.9% TOC – Total Organic Carbon) from the stratotype section of the Bravaisberget Formation (western Spitsbergen) were analyzed with respect to isotopic composition of pyritic sulphur (34S) and TOC. Isotopic composition of syngenetic py− rite−bound sulphur shows wide (34S from −26‰ to +8‰ VCDT) and narrow (34S from −4‰ to +17‰ VCDT) variation of the 34S in upper and lower part of the section, respec− tively. Range of the variation is associated with abrupt changes in dominant lithology. Wide 34S variation is found in lithological intervals characterized by alternation of black shales and phosphorite−bearing sandstones. The narrow 34S variation is associated with the lithological interval dominated by black shales only. Wide and narrow variation of the #2;34S values suggests interplay of various factors in sedimentary environment. These fac− tors include oxygen concentration, clastic sedimentation rate, bottom currents and bur− rowing activity. Biological productivity and rate of dissimilatory sulphate reduction had important impact on the 34S variation as well. Wide variation of the 34S values in the studied section resulted from high biological productivity and high rate of dissimilatory sulphate reduction. Variable degree of clastic sedimentation rate and burrowing activity as well as the activity of poorly oxygenated bottom currents could also cause a co−occurrence of isotopically light and heavy pyrite in differentiated diagenetic micro−environments. Occurrence of organic matter depleted in hydrogen could also result in a wide variation of the 34S values. Narrow variation of the #2;34S values was due to a decrease of biological productivity and low rate of dissimilatory sulphate reduction. Low organic matter supply, low oxygen concentration and bottom currents and burrowing activity were also responsible for narrow variation of the 34S. The narrow range of the 34S variation was also due to occurrence of hydrogen−rich organic matter. In the studied section the major change in range of the 34S variation from wide to narrow appears to be abrupt and clearly associated with change in lithology. The change of lithology and isotopic valuesmay sug− gest evolution of the sedimentary environment from high− to low−energy and also facies succession from shallow to deeper shelf. The evolution should be linked with the Late Anisian regional transgressive pulse in the Boreal Ocean.
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Abstract

Experiments have been carried out on the influence exerted by Aroclor 1254 upon the photosynthetic production of organic 14C by an assemblage of marine Antarctic diatoms (Thalassiosira sp. 48%, Nitzschia sp. 21%, Chaetoceros sp. 15% and Corethron iriophilum 10%). Samples of various numbers of cells per cm3 of water have been used. Incorporation of 14C02 by the diatoms proved to be proportional to the increased number of cells in the sample only at the lowest levels of concentration in per cm3. Further increase of the level of 14C in diatoms has not been found as number of cells in the sample kept growing. Calculation of brutto photosynthesis has indicated that low concentration of Aroclor 1254 (0,01 to 1 ppm) may stimulate the photosynthetic incorporation of carbon, yet the photosynthetic release of carbon from cells within the photorespiratory process is stimulated to a higher degree. High concentration of Aroclor (1 to 50 ppm) inhibit the brutto assimilation, yet the release of carbon during the photorespiratory process is inhibited to a higher degree. A hypothesis is being considered implying that the relation between the intensity of photosynthesis and intensity of photorespiration may vary according to the rate of concentration of Aroclor.
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Abstract

The airflow in the mouth of an open and closed flue organ pipe of corresponding geometrical proportions is studied. The phase locked particle image velocimetry with subsequent analysis by the biorthogonal decomposition is employed in order to compare the flow mechanisms and related features. The most significant differences lie in the mean velocity distribution and rapidity of the jet lateral motion. Remarks on the pressure estimation from PIV data and its importance for the aeroacoustic source terms are made and a specific example is discussed.
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Abstract

Turbine stages can be divided into two types: impulse stages and reaction stages. The advantages of one type over the second one are generally known based on the basic physics of turbine stage. In this paper these differences between mentioned two types of turbines were indicated on the example of single stage turbines dedicated to work in organic Rankine cycle (ORC) power systems. The turbines for two ORC cases were analysed: the plant generating up to 30 kW and up to 300 kW of net electric power, respectively. Mentioned ORC systems operate with different working fluids: DMC (dimethyl carbonate) for the 30 kW power plant and MM (hexamethyldisiloxane) for the 300 kW power plant. The turbines were compared according to three major issues: thermodynamic and aerodynamic performance, mechanical and manufacturing aspects. The analysis was performed by means of the 0D turbomachinery theory and 3D computational aerodynamic calculations. As a result of this analysis, the paper indicates conclusions which type of turbine is a recommended choice to use in ORC systems taking into account the features of these systems.
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Abstract

A sediment core (LS-1) collected from Long Lake in King George Island, South Shetland Islands (West Antarctica) was analyzed for a variety of textural, geochemical, isotopic and paleontological properties together with 14C age dates. These data combined with published records of other studies provide a detailed history of local/regional postglacial paleoproductivity variation with respect to terrestrial paleoclimate change. The lithologic contrast of a lower diamicton and an upper fine-grained sediment demonstrates glacial recession and subsequent lake formation. The upper fine-grained deposit, intercalated by mid-Holocene tephra-fallout followed by a tephra gravity flow, was formed in a lacustrine environment. Low total organic carbon (TOC) and biogenic silica (Sibio) contents with high C/N ratios characterize the diamicton, whereas an increase of TOC and Sibio contents characterize the postglacial lacustrine fine-grained sediments, which are dated at c. 4000 yrBP. More notable are the distinct TOC maxima, which may imply enhanced primary productivity during warm periods. Changes in Sibio content and δ13C values, which support the increasing paleoproductivity, are in sympathy with these organic matter variations. The uniform and low TOC contents that are decoupled by Sibio contents are attributed to the tephra gravity flows during the evolution of the lake rather than a reduced paleoproductivity. A very recent TOC maximum is also characterized by high Sibio content and δ13C values, clearly indicating increased paleoproductivity consequent upon gradual warming across King George Island . Comparable with changes in sediment geochemistry, the occurrence and abundance of several diatom species corroborate the paleoproductivity variations together with the lithologic development. However, the paleoclimatic signature in local terrestrial lake environment during the postglacial period (for example the Long Lake) seems to be less distinct, as compared to the marine environment.
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Abstract

Measurements were made of organic fluxes at a coastal sediment at Signy Island , South Orkney Islands, Antarctica , between December 1990 and March 1992. The deposition rate of organic matter to the sediment was measured at the same time with a maximum sedimentation rate of 306 mg C m–2 d–1. The rates of sedimentary organic input were small during winter ice cover, and the organic content of the sediment declined during this period as available organic matter was depleted. Fresh organic input occurred as soon as the sea-ice melted and ice algal biomass was deposited to the sediment; and was sustained during the spring after ice break-up by continued primary production in the water column. The proportion of available carbon in surface sediments was measured during a seasonal cycle using Pseudomonas aeruginosa as an indicator organism over the 0–1 cm depth horizon. Variations in the amount of organic matter deposited to the sediments and the proportion of available carbon were observed during the seasonal cycle. Seasonal variations of benthic activity in this coastal sediment was regulated by the input and availability of organic matter, and not by seasonal water temperature, which was relatively constant between –1.8 and 0.5°C .
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Abstract

In general, Antarctic marine bacteria are small, with biovolumes ranging from 0.139 to 0.204 μm-3 cell-1, but their total biomass in seawater is considerable due to relatively high numbers that approximate to 1020 cells km-3. Bacterial biomass becomes more concentrated closer to land. Our multi-year Antarctic studies demonstrated an average total bacterial biomass of 504 tons in Admirality Bay (24 km3) or 21 tons per 1 km3, versus 6.4 tons per 1 km3 in the open ocean. Strikingly, bacterial biomass reached 330 tons per 1 km3 of seawater at the sea-ice edge, as sampled in Goulden Cove in Admiralty Bay. Bacterial biomass in Admirality Bay, which we believe can be enriched by halotolerant and thermotolerant fresh water bacteria from glacial streams, is equal to or even exceeds that of the standing stock of krill (100-630 tons per bay) or other major living components, including phytoplankton (657 tons), flagellates (591 tons), and ciliates (412 tons). However, the bacterial biomass is exceeded by several orders of magnitude by non-living organic matter, which constitutes the basic bacterial carbon source. Factors regulating high bacterial abundance in the vicinity of land are discussed.
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Abstract

The aim of this paper is to reflect on the role of non-governmental organizations in contemporary cities. It is assumed that post-socialist cities are subjected to changes related to new models of citizenship as well as new models of urban social movements. First, a general picture of Polish non-governmental sector is presented. Next the idea of social movements in a post socialist city is given. The following part presents the idea of NGO as agents of a social change.Th e notions of social conflict, common good and a collective identity are used. The paper sums up with conclusions and a demand to built coalitions between different social actors.
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Abstract

Humic acids, isolated from selected soils of Grønfjorden area (Spitsbergen) were investigated in terms of molecular composition and resistance of decomposition. The degree of soils organic matter stabilization has been assessed with the use of modern instrumental methods (nuclear magnetic resonance spectroscopy (CP/MAS 13C-NMR). Analysis of the humic acids showed that aromatic compounds prevail in the organic matter formed in cryoconites, located on the glaciers surfaces. The predominance of aliphatic fragments is revealed in the soils in tidal zone that form on the coastal terrace. This could be caused by sedimentation of fresh organic matter exhibiting low decomposition stage due to the harsh climate and processes of hydrogenation in the humic acids, destruction of the C-C bonds and formation of chains with a high hydrogen content. These processes result in formation of aliphatic fragments in the humic acids. In general, soils of the studied region characterizes by low stabilized soil organic matter which is indicated by low aromaticity of the HAs.
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Abstract

The paper illustrates a case study of fluid selection for an internal combustion engine heat recovery organic Rankine cycle (ORC) system having the net power of about 30 kW. Various criteria of fluid selection are discussed. Particular attention is paid to thermodynamic performance of the system and human safety. The selection of working fluid for the ORC system has a large impact on the next steps of the design process, i.e., the working substance affects the turbine design and the size and type of heat exchangers. The final choice is usually a compromise between thermodynamic performance, safety and impact on natural environment. The most important parameters in thermodynamic analysis include calculations of net generated power and ORC cycle efficiency. Some level of toxicity and flammability can be accepted only if the leakages are very low. The fluid thermal stability level has to be taken into account too. The economy is a key aspect from the commercial point of view and that includes not only the fluid cost but also other costs which are the consequence of particular fluid selection. The paper discusses various configurations of the ORC system – with and without a regenerator and with direct or indirect evaporation. The selected working fluids for the considered particular power plant include toluene, DMC (dimethyl carbonate) and MM (hexamethyldisiloxane). Their advantages and disadvantages are outlined.
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Abstract

The study of the relationship “the natural qualities of water – the naturally built environment – the psycho- emotional conditions of human beings” from the perspective of architectural and landscape organization is essential nowadays. By investigating modern monuments we identified the methods of landscaping and composition planning to create the appropriate environment to emotionally impact the persons dealing with grief, sadness and loss. The conducted analysis of modern memorials allowed us to explore the role of water as an important compositional element in the architectural and landscape organization of monument sites. We also identified different methods of modeling water and how they affect related emotional impressions in creating the urban social environment that would preserve the historical and cultural memory from generation to generation.
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Abstract

Is the fact that the majority of the population in the Middle East belongs to Islam actually the reason why human rights in Muslim-majority countries appear to be so difficult to work out and enforce? Are Islam and human rights not basically compatible? Historically it cannot be disputed that the thought of human rights first took shape in the European and Western context. Over the course of several centuries, it became widely accepted, and finally the thought of human rights also became a political reality as they were implemented in democratic states and constitutions. However, it would be a wrong conslusion, as for instance has been emphasized by Heiner Bielefeldt, the former United Nations Special Rapporteur on freedom of religion or belief, to say that the ability to implement human rights, in particular thoughts about freedom and the equality of all people, is a one-sided affair and can only occur in the Western-Christian context. As far as Heiner Bielefeldt is concerned, this historic development, however, justifies neither the assertion that it had to happen as it did, nor does it justify Western representatives’ taking sole occupation of considerations relating to human rights thinking. Viewed from this perspective, human rights cannot boast a “Western” origin or a “Christian” character in a way that they would be incompatible with notions justified by Islam. Having that said, one is still to a large degree able to recognize a desolate situation in matters relating to human rights in Muslim-majority countries. But conflicts between Islam and human rights do not arise automatically out of the religious affiliation of a majority of the people. They certainly do stand out in those places where for political decision-making authorities Sharia law ranks higher than human rights and the granting of human rights is made dependent upon a traditional interpretation of the Sharia. Apart from the societal advocacy of human rights, there is the question as to the framework within which theological assessments of human rights questions occur. The following article aims at pointing to three discernable positions about human rights in the context of Islamic theologians, the a) the inclusive position, b) the pragmatic position, and c) the progressive position.
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