The distribution of planktonic Ostracoda (Halocyprididae) was studied based on vertically-stratified zooplankton samples collected by hauling 200 p.m - mesh net by day and by night during two austral seasons: summer 1985/1986 and winter 1989, from the 1200 m deep Croker Passage off the Antarctic Peninsula. Seven species of Ostracoda were recorded: Alacia belgicae, Alacia hettacra, Melaconchoecia isocheira, Metaconchoecia skogsbergi, Boroecia antipoda, Disconchoecia aff. elegans and Proceroecia brachyaskos. The first three species, endemic to Antarctic waters, were predominant (about 90%). Generally Ostracoda were most numerous in 600-200 m layer in summer and in 1000-400 m layer in winter. In the investigated area there was a clear contrast between the abundance of Ostracoda during austral summer and scarcity during austral winter.
In 1920 qualitative and quantitative benthos samples collected in Barents Sea sublittoral in the years 1951-1983 154 species, 77 genera and 30 families of Amphipoda Gammaridea were identified. Species diversity was highest among the Lysianassidae, Oedicerotidae, Ampcliscidae, Calliopiidae and Pleustidae. Ampelisca eschrichti clearly dominated the material. This same species, plus Haploops setosa and Anonyx nugax were both the most frequently occurring and most numerous species. The distribution of amphipods in the Barents Sea sublittoral varies both in diversity and numbers by region, depth, sediments and water temperature. Zoogeographical changes are discussed in the present paper. Altogether 331 species of amphipods have been hitherto collected in the Barents Sea, of which 317 species, 126 genera and 39 families belong to the suborder Gammaridea.
In the material of nearly 2000 individuals of Asteroidea collected in Admiralty Bay, the largest bay of the South Shetlands, 36 species were determined, enriching the list of hitherto known asteroid species of this basin by 17 taxa. One of them, Peribolaster macleani, is recorded for the first time in Western Antarctic. The most frequent and abundant asteroids of Admiralty Bay were Odonlaster validus, Psilaster charcoti, Bathybiaster loripes obesus and Diplasterias brucei. The bathymetric and geographic distribution of all species are discussed.
The avifaunistic observations carried out in the tundra valley of the Sob River's upper course (west slopes of the Polar Ural) in July 1995 revealed the occurrence of 39 breeding and 8 non-breeding bird species. The most numerous were Anthus pratensis, Calcarius lapponicus, Phylloscopus trochilus and Anthus cervinus. The great variety of wetland and aquatic habitats had a decisive influence on species-richness and abundance of birds (jointly 30 breeding and 4 non-breeding species). Areas of low humidity were inhabited by 14 whereas anthropogenic habitats by 4 species. Most of them (except for eurytopic A. pratensis and C. lapponicus) occupied one-two habitats irrespective of their numbers. The density of Buteo lagopus was estimated at 1.67-2.00 p/10 km2. Three species of distribution ranges laying to the south from the study area, namely Bucephala clangula, Dendrocopos major, Circus macrourus, were noted in the valley. The results obtained have been compared with available data on the avifauna of the region concerned.
226 papers by Polish authors and co-authors have been collected. They deal with Antarctic or sub-Antarctic fishes and also their parasites. The majority (35.7%) of the publications discuss fish biology including growth, age, maturity, feeding and occurrence of particular species in the area. Fewer papers are devoted to parasitology (26.0%). Papers dealing with fish biomass and exploitation make up 18.5%. Papers dealing with morphology and systematics make up 6.6%. The remaining papers are devoted to technology, physiology, palaeontology and others.
Starostinella nordica gen. et sp. n. is described from the uppermost Permian (Kapp Starostin Formation) of the Kapp Starostin (Isfjorden) in West Spitsbergen. The new genus is attributed to Trachypsammiidae Gerth - a family incertae sedis among Cnidaria. Members of the Trachypsammiidae have been previously associated with different higher rank taxa within the Cnidaria, or their skeletons were interpreted as a result of symbiosis of a cladochonoidal organism (Tabulata) with an indeterminate hydroid or stromatoporoid. S. nordica gen. et sp. n. seems to support the latter assumption. Hydrocoralla of S. nordica have a simpler structure than those of other Trachypsammiidae and are branching like those of Cladochonus. Their thick-walled, horn-shaped hydrocorallites are surrounded with a very thick cortical zone of sclerenchyme organized into trabecular microstructure. The proper corallite wall is fibro-radial in structure, sharply distinct from the outer cortical zone.
Properties of a snow cover in the vicinity of Arctowski Station, King George Island (West Antarctica) were studied in 1991. Variations of snow quality and physical transformations were analysed against changes of atmospheric parameters, basing on water equivalent index and repeatable examination of snow pits. Essential dependence of snow cover distribution and snow structure from local climatic features and terrain morphology was found. Thawing occurs in the whole mass of snow, with its contribution of both liquid and gas water phases.
Mid-winter rapid rise of temperature in the vicinity of Arctowski Station, King George Island (West Antarctica) was studied in 1991. Depending on circumantarctic migration of cyclones, sudden drop in air pressure and foehn-like phenomenon intensified by local topography occurred. Two such events are described on May 13 and June 28, against meteorological conditions during autumn and winter. Extreme intensification of morphogenetic processes caused degradation of a snow cover, immense meltwater discharge, radical transformation of slopes, effective aeolian activity and dynamic modifications in a sea-shore zone.
Peat soils (FAO — Gelic Histosols) in the southern Bellsund coast area occur on slopes and terraces. They are formed in places favourable for plant growth, i.e. adequately moistened and fertilized largely with bird excrements. These formations belong to moss peats which are generally decomposed weakly and moderately to about 0.5 m depth. Their content of organic matter is equal to about 30-90%, but it is higher in terrace peats. The latter are more acidified than slope peats. The reaction both of slope and terrace peat soils is as a rule, slightly acid or neutral, and CaC03 content does not exceed 10%. As regards the content of macroelements, that of Al is the highest followed by Ca, Fe, Mg and P. Little K and Ti, and only traces of Na are found. Microelements occur in the following sequence: Mn, Zn, Cu, Cr, Ni, Pb, Co, Cd. Particularly Mn, Zn as well as Cu and Cd were found in a higher concentration. Slope peat soils are richer in macro- and microelements than terrace ones, e.g. 4 times in the case of Mg. Peat soils poor in ash parts (up to 25% ash), contain the fewest elements. Some regularities concern also a vertical distribution of the particular profiles but only with regard to terrace peat soils.
The paper presents a spatial distribution of changes of air temperature (T) in the Arctic. Estimates of their spatial relations in the study region were based on a correlation analysis. T in the Arctic is most strongly correlated spatially in winter and spring, and least in summer. The radius of extent of statistically significant correlation coefficients of changes of T at the stations Svalbard Lufthavn, Ostrov Kotelny and Resolute A is equal to 2000-2500 km in winter and 1500-2000 km in summer. An attempt was done to delimit the regions of consistent occurrence of the anomalies T with respect to the signs and magnitudes, as well as of the regions with the most coherent T. The Wroclaw dendrite method was used to solve this problem. Relations of the mean areał T of the climatic regions and of the Arctic as a whole, with the northern hemisphere of temperature and selected climatic factors are presented.
Henryk Arctowski Station, the research station of the Polish Academy of Science in Admiralty Bay, King George Island, West Antarctica, is one of the most heavily visited bases in Antarctica. Between the seasons 1991/92 and 1996/97, 12884 tourists were recorded. A specially designed tourist trail was marked to divert visitors toward alternative attractions, not only the station buildings. Tourist management goals include: environmental protection, minimising waste and pollution, respecting the rules relating to protected areas, and prohibition of collections and souveniring.
Four Geodynamical Expeditions of the Polish Academy of Sciences carried through wide research seismic program in West Antarctica in 1979-1991. Three of these expeditions operated in the Bransfield Strait. The experiment of deep refraction and wide-angle reflection in West Antarctica focused on deep structure of the lithosphere, mainly of the Earth's crust. The network of deep seismic soundings (DSS) profiles covered all the Bransfield Strait. Five land stations on the South Shetland Islands, three stations on the Antarctic Peninsula and nine ocean bottom seismographs (OBS) recorded seismic waves, generated by explosions in a sea. The Bransfield Rift and the Bransfield Platform form a marginal basin against a volcanic arc of the South Shetland Islands. The paper presents new results of 2-D seismic modeling for network of five selected profiles. Four of them, ranging in lenght from 150 to 190 km, crossed main structures of the Bransfield Strait and the fifth, which connected the other ones and was 310 km long, ran along the Bransfield Rift. Two or three seismic models were presented for each profile. Finally, mutually corrected and controlled 2-D models of described profiles were constructed. They all presented spatial complex structure of the Earth's crust in a young rift of the Bransfield Strait, including extent of its main element i.e. anomalous high velocity body (HVB) (Vp > 7.4 km/s), detected in 10-30 km depth range except profile DSS-4 (southwest part of the Bransfield Strait). This inhomogeneity is interpreted as intrusion of the upper mantle (?asthenosphere) during stretching of the continental crust. The Moho discontinuity was found at depth 30-35 km, with velocities equal to about 8.1 km/s.
The paper presents the results of an investigation of the thermal deformation of moulding sands with an inorganic (geopolymer) binder with a relaxation additive, whose main task is to reduce the final (residual) strength and improves knocking-out properties of moulding sand. The moulding sand without a relaxation additive was the reference point. The research was carried out using the hot-distortion method (DMA apparatus from Multiserw-Morek). The results were combined with linear deformation studies with determination of the linear expansion factor (Netzsch DIL 402C dilatometer). The study showed that the introduction of relaxation additive has a positive effect on the thermal stability of moulding sand by limiting the measured deformation value, in relation to the moulding sand without additive. In addition, a relaxation additive slightly changes the course of the dilatometric curve. Change in the linear dimension of the moulding sand sample with the relaxation additive differs by only 0.05%, in comparison to the moulding sand without additive.
Silicon – molybdenum cast iron commonly called SiMo due to its unique properties has becoming more and more interesting engineering material. The history and development of this alloy is relatively long but, due to the significant difficulties during the manufacturing process resulting in the lower final quality than expected, it has not been applied to often in practice. The biggest challenge is its brittleness as a result of the carbides precipitations. During last few years, thanks to the many important researches made and the general foundry technology development, the interest in SiMo iron has been rapidly growing, especially for the castings for heavy duty applications like corrosion, high temperature and wear abrasion resistant parts. In the article the heat treatment attempts to improve the microstructure of SiMo castings has been presented. The goal was to destroy or at least to refine and uniformly distribute the carbides precipitations to improve mechanical properties of the exhaust manifold castings for the cars. The experiments were carried out for the alloy contains approx. 4% Si, 1% Mo and 3.2%C. The range of the research included: hardness measuring, standard mechanical properties and microstructure for as-cast state and after that the subsequent heat treatment process with another properties check. The result of the heat treatment was the elimination of pearlite from the metal matrix. Moreover, the changes of the carbide molybdenum – rich phase morphology were observed. The dispersion of the carbides precipitations in the carbides area was observed. The experiments proved the possibility to control the microstructure and the mechanical properties of the SiMo castings by means of heat treatment but only to some extent.
One of the biggest problems for sand casting foundries must be the waste produced from disposable molds. Stricter environmental regulations make it harder to dispose of waste sand, so a truly competitive foundry does no longer only make great products, but also concentrates on a sustainable casting process. While methods for repurposing waste foundry sand are still limited, the internal circulation of such sands proves significant possibilities. This paper will focus on thermal reclamation of foundry sands in a special rotating drum furnace in a central facility to serve several foundries. Thermal reclamation is a process for handling foundry sands in elevated temperatures to combust unwanted substances from reusable base sand. The introduction focuses on background of the Finnish foundry business, the most common sand systems in Finland and their reclaim properties. The experimental part features presentation of the new reclamation plant process and the conducted test runs. The samples collected from each test run have been laboratory tested to assure proper sand quality. The results of this work showed that the reclamation of alkaline phenolic no-bake sands was excellent. Reclamation of green sands did not provide satisfactory results as expected and the reclamation of furan no-bake sands provided mixed results, as the raw material was imperfect to begin with. The most important result of this work is still the successful initiation of a centralized thermal reclamation plant, with the ability to reclaim sands of several foundries. With this all of industrial symbiosis, circular economy and sustainability advanced in Finland, and the future development of this plant provides even further opportunities and a possibility to spread the ideas on a global scale.
The essence of ablation casting technology consists in pouring castings in single-use moulds made from the mixture of sand and a watersoluble binder. After pouring the mould with liquid metal, while the casting is still solidifying, the mould destruction (washing out, erosion) takes place using a stream of cooling medium, which in this case is water. This paper focuses on the selection of moulding sands with hydrated sodium silicate for moulds used in the ablation casting. The research is based on the use of Cordis binder produced by the Hüttenes-Albertus Company. It is a new-generation inorganic binder based on hydrated sodium silicate. Its hardening takes place under the effect of high temperature. As part of the research, loose moulding mixtures based on the silica sand with different content of Cordis binder and special Anorgit additive were prepared. The reference material was sand mixture without the additive. The review of literature data and the results of own studies have shown that moulding sand with hydrated sodium silicate hardened by dehydration is characterized by sufficient strength properties to be used in the ablation casting process. Additionally, at the Foundry Research Institute in Krakow, preliminary semi-industrial tests were carried out on the use of Cordis sand technology in the manufacture of moulds for ablation casting. The possibility to use these sand mixtures has been confirmed in terms of both casting surface quality and sand reclamation.