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Number of results: 45
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Abstract

The authors describe the scope of Polish studies in the field of biology and ecology carried on during 20 years of activity of Polish Antarctic Station. Principal results are briefly summarized and ample literature is presented.
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Abstract

A total of sixty five taxa of marine phytoplankton (diatoms, dinoflagellates, silicoflagellates and cyanoprokaryotes) were recorded in the transect from the cold region of the Antarctic (Weddell Sea) up to La Plata Bay, Argentine in the late austral summer (March 1989). Diatoms were the dominant group in a south-north transect from the Seal-Bay (Princess Martha Land, the Antarctic). Most of the phytoplankton species of the cold Antarctic region disappeared around 50°S where there is a steep water temperature gradient. The diatom flora declined in the regions of increasing temperature, i.e. between 60° and 50° S and was replaced by dinoflagellates of the genus Ceratium. Large centric diatom genera Corethron, Rhizosolenia, Chaetoceros and Dactyliosolen represented the most apparent phytoplankton part. The most common of the small centric diatom genera were Thalassiosira, Asteromphalus, Actinocyclus and Coscinodiscus, while several species of Navicula and Nitzschia were the most abundant pennate forms. The presence of a considerable number of freshwater pennate diatoms, characterized as indifferent in the halobion spectrum and mostly periphytic, might be attributed to survival strategies during their development on the floating coastal ice.
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Abstract

Phytoplankton samples were collected at 141 stations in the Norwegian, Greenland, Barents and Baltic seas, in July-August 1992 and July-August 1993. In fifteen of these stations 22 unarmoured dinoflagellate species from the order Gymnodiniales belonging to the genera Amphidinium, Cochlodinium, Gymnodinium, Gyrodinium, Torodinium and Polykrikos have been found. Data on 16 species are given here, including synonyms, size or size variation, localities and environmental factors (temperature and salinity at the surface). 14 species are illustrated.
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Abstract

Suspended matter, phytoplankton and light attenuation were investigated in various North East Greenland, Svalbard and Siberian river mouths in 1992-1994. The amount of mineral suspensions well correlated with freshwater discharge in the case of tidal glacier bays, while such correlation in Siberian rivers and pack ice meltwater was not found. Freshwater phytoplankton species were found in Siberian estuaries only and in two other ecosystems marine and ice phytoplankton species prevailed. The light attenuation connected with freshwater discharge seems to be a key factor limiting primary production in coastal Actic waters in the summer. The amount of glacial suspensions well correlated with the salinity drop in the case of Svalbard, while Siberian river estuaries produced very turbid waters with the suspension loads not correlated to freshwater or depth.
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Abstract

This paper reports the preliminary results from the studies on the scanning electron microscopical studies on chrysophycean cysts collected in ponds and streams of King George Island (South Shetlands). The cysts play an important role as the survival developmental stages. Fifteen morphotypes are described, six of which are new for science. Particular attention has been paid to the anatomy of the pore, collar structure and to the ornamentation of the cyst surface.
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Abstract

The paper presents the results of seven-year survey of Antarctic seals along the western shore of Admiralty Bay, King George Island, South Shetland Islands. Five species were monitored during seven of the eight years, between 1988-95, excluding 1993. Numbers of elephant seals and Antarctic fur seals showed strong annual cycles, fur seals with two seasonal peaks. These of the other three species were more irregular. Fewer Weddell seals were seen in 1994 and 1995 then during the period 1988-92; with this exception, no overall trend in numbers was apparent during the period 1988-95.
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Abstract

Alongside the purely scientific nature and the first wintering in Antarctica, another innovative feature of the Belgica expedition was its multinational composition. Two, out of its seven persons strong scientific staff, were Polish - H. Arctowski and A. B. Dobrowolski. The first served as scientific deputy-leader of the expedition, the other as laboratory assistant and meteorologist. Their contribution to the scientific success of the Belgian Antarctic Expedition outlined in the present paper, turned into the starting point of brilliant academic careers in the native country and at international level. Both, Arctowski and Dobrowolski, were acknowledged as symbols of the Polish explorations and scientific investigations in polar regions.
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Abstract

The paper provides information on oceanobiological expeditions to the Antarctic organized by Polish Academy of Sciences. The scope of research of five expeditions is described and main achievements of Polish Antarctic studies are summarized.
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Abstract

Polish exploration and exploitation of marine resources of Antarctic waters date back to the reconnaissance cruise of the Sea Fisheries Institutes (SFI) r/v Profesor Siedlecki in 1974. Since 1975, a co-operation between the Institute of Ecology, Polish Academy of Sciences (PAS) at Dziekanów Leśny and SFI in Gdynia with participation of the University of Agriculture in Szczecin, Faculty Marine Fisheries and Food Technology (UA) was established. Fishing fleets of the Polish Deep-Sea Fisheries Companies Odra, Dalmor and Gryf, since 1976 were operating in the Atlantic sector of Antarctic waters, south of the convergence.
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Abstract

A. B. Dobrowolski, a member of the Belgian expedition in Belgica to West Antarctica (1897-1899), after his return home became a strong supporter of Polish scientific activity in the Polar countries. His patronage - called by him the "Polar Action", was especially well marked during organization of three Polish expeditions to the Svalbard archipelago: to Bear Island during the 2nd Polar Year, 1932-33 and to Spitsbergen in 1934 and 1938. Apart from his scientific achievements in Antarctica, Dobrowolski was also widely known as an author of popular-scientific books on history of discovery and exploration in the Arctic and the Antarctic.
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Abstract

The article presents a review of the researches on sea and atmospheric physics conducted by the Polish expeditions in Antarctica from 1977 to 1990.
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Abstract

During the Polish Geodynamic Expeditions to West Antarctica, 1984-1991, led by A. Guterch, the scientific research of the geological group (leader K. Birkenmajer) included stratigraphic, sedimentological, petrological, tectonic, volcanological and Quaternary geology studies. They were caried out mainly in the area of Antarctic Peninsula, Palmer Archipelago and South Shetland Islands (the results from King George Island have been reviewed separately, in 1996). The major scientific archievements are: (1) introduction of formal lithostrati-graphical standards, recognition of tectonic structure, and sedimentological characteristics of the Trinity Peninsula Group (?Upper Permian-Triassic) metasediments (Antarctic Peninsula: Hope Bay and Paradise Harbour; Livingston Island: Hurd Peninsula); (2) elaboration of Late Mesozoic-TTertiary magmatic successions (Antarctic Peninsula Volcanic Group and Andean Intrusive Suite) on northern Antarctic Peninsula (Hope Bay; Arctowski Peninsula; Paradise Harbour - Gerlache Strait); (3) together with geophysical group: elaboration of lithospheric transect from South Shetland Islands to Antarctic Peninsula; (4) elaboration of Late Cenozoic evolution stages of the Bransfield Basin and Rift, as based on geological and palaeontological record; (5) introduction of a revised volcanostratigraphic standard, and reconstruction of evolution stages, of the Deception Island volcano (South Shetland Islands); (6) reconstruction of the Holocene history in some areas of Antarctic Peninsula (Hope Bay) and South Shetland Islands (King George Island). The results of palaeontological and sedimentological research on Seymour and Cockburn islands (NE Antarctic Peninsula) were presented separately.
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Abstract

The paper presents a catalogue, with description, detailed map location and references to first publications, of new place names introduced mainly during the Polish Geodynamic Expeditions to West Antarctica, 1984-1991. In the South Shetland Islands, new place names were introduced in parts of King George Island and Deception Island (Some new names for Admiralty Bay, King George Island and Penguin Island, introduced prior to 1984 but not yet formally described, are also included here). In Antarctic Peninsula, new place names have been introduced at Hope Bay (Trinity Peninsula), Arctowski Peninsula-Andvord Bay (Danco Coast/Gerlache Strait) and Paradise Harbour (Danco Coast).
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Abstract

This paper deals with the complete technology of inorganic geopolymer binder system GEOPOL® which is a result of long term research and development. The objective of this paper is to provide a theoretical and practical overview of the GEOPOL® binder system and introduce possible ways of moulds and cores production in foundries. GEOPOL® is a unique inorganic binder system, which is needed and welcomed in terms of the environment, the work environment, and the sustainable resources. The GEOPOL® technology is currently used in the foundries for three basic production processes/technologies: (1) for self-hardening moulding mixtures, (2) sand mixtures hardened by gaseous carbon dioxide and (3) the hot box technology with hot air hardening. The GEOPOL® technology not only solves the binder system and the ways of hardening, but also deals with the entire foundry production process. Low emissions produced during mixing of sand, moulding, handling, and pouring bring a relatively significant improvement of work conditions in foundries (no VOCs). A high percentage of the reclaim sand can be used again for the preparation of the moulding mixture.
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Abstract

In 2014 we finished research works involved in the development of a technology for manufacturing innovative ceramic-carbon foam filters for molten metal alloys filtration, which were financed by the National Centre for Research and Development (NCBiR) from INNOTECH programme resources. A batch of the filters produced in this technology was tested in practice in domestic cast steel and cast iron foundries. The trials were successful and foundries declared their intention to purchase the newly-developed filters for the current production of casts. This provided an incentive for “Ferro-Term” Sp. z o.o. to start design works on the prototype line for a serial production of these filters. At the same time, in co-operation with a scientific consortium, including the co-authors of the technology, i.e. the Institute of Ceramics and Building Materials, Refractory Materials Division in Gliwice, Institute for the Chemical Processing of Coal in Zabrze and Foundry Research Institute in Cracow, the company made a successful attempt to raise some funds for the necessary adaptation of the developed technology from the semi-technical to industrial scale from Intelligent Development Operational Programme. In the article we have presented information on the effects of works performed within the framework of the project entitled “Modernization and adaptation of the existing technological line for purposes related to technology verification and start-up of the production of innovative ceramic-carbon filters for molten metal alloy filtration”.
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Abstract

The profile of the Polish foundry engineer in the Industry 4.0 age is presented in the present paper. The presented results were obtained by means of three research methods consisting of: analyses of professional expertise documents, questionnaires filled-up by the executive staff of foundry enterprises and analyses of work offers for the foundry engineer position. The investigations indicated the key competences of the foundry engineer, demanded currently by employers and meeting the requirements of the Polish foundry sector. The obtained results were discussed in relation to the fourth industrial revolution and its requirements with regard to the engineering staff. This concept is based on information technology and robotizing, which means the total automation of industrial production processes as well as the widespread access to data and machines. Such an approach requires changes in applied machines, technologies and employees’ competencies. The competences of employees constitute the element deciding on the company success, aimed at obtaining a competitive advantage. Therefore adjusting the employees’ competencies to continuously changing reality is so essential.
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Abstract

The conducted work shows and confirms how thermal analysis of grey and ductile iron is an important source for calculating metallurgical data to be used as input to increase the precision in simulation of cooling and solidification of cast iron. The aim with the methodology is to achieve a higher quality in the prediction of macro– and micro porosity in castings. As comparison objects standard type of sampling cups for thermal analysis (solidification module M ≈ 0.6 cm) is used. The results from thermal analysis elaborated with the ATAS MetStar system are evaluated parallel with the material quality (including tendency to external and internal defects) of the tested specimen. Significant temperatures and calculated quality parameters are evaluated in the ATAS MetStar system and used as input to calibrate the density curve as temperature function in NovaFlow&Solid simulation system. The modified data are imported to the NovaFlow&Solid simulation system and compared with real results.
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Abstract

The influence of the chill on the AlSi7Mg alloy properties after the heat treatment T6, was realised in the system of the horizontally cast plate of dimensions 160x240 mm and thickness of 10 and 15 m. The cooling course in individual casting zones was recorded, which allowed to determine the solidification rate. Castings were subjected to the heat treatment T6 process. Several properties of the alloy such as: hardness BHN, density, tensile strength UTS, elongation %E were determined. The microstructure images were presented and the structural SDAS parameter determined. The performed investigations as well as the analysis of the results allowed to determine the influence zone of the chill. The research shows that there is a certain dependence between the thickness of the casting wall and the influence zone of the chill, being not less than 2g, where g is the casting wall thickness. The next aim of successive investigations will be finding the confirmation that there is the dependence between the casting wall thickness and the influence zone of the chill for other thicknesses of walls. We would like to prove that this principle is of a universal character.
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Abstract

Variation in final casting dimensions is a major challenge in the investment casting industry. Additional correction operations such as die tool reworking as well as coining operations affect foundry productivity significantly. In this paper influence of basic parameters such as wax material, mould material, number of ceramic coats and feed location on the dimensional accuracy of stainless-steel casting has been investigated. Two levels of each factor were chosen for experimental study. Taguchi approach has been used to design the experiment and to identify the optimal condition of each parameter for reduced dimensional deviation. Analysis of variance has been carried out to determine the contribution of each process parameter. The result reports that selected parameters have significant effect on the dimensional variability of investment casting. Mould material is the dominant parameter with the largest contribution followed by number of ceramic coats and wax material whereas feed location is having negligible contribution.
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Abstract

The article presents an integrated analytical and measurement system for evaluation of the properties of cast metals and alloys. The presented platform is an extension of the SLAG - PROP application with new modules, which allow to use information on metallurgical processes in an even more effective way, as well as to evaluate the finished product. In addition, the construction of a measuring station for the analysis of thermal processes taking place in a metal bath allows for precise observation of phenomena together with their appropriate interpretation. The article presents not only the cooling curves of certain copper alloys. The analysis also covered mechanical properties related to hardness, finished products depending on the mold in which the products were cast. In the literature one can find information about the mechanical properties of products in the improved state, usually after plastic or thermal treatment, omitting their properties obtained as a result of a naturally made casting. The article also presents the method of placing information in the database using a convenient graphical tool.
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