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Number of results: 8
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Abstract

Temperature of superficial water in the Ezcurra Inlet was measured from March 1989 to February 1990, with a use of a mercurial thermometer with accuracy +0.1°C. Temperature was measured usually once a month at selected points. Influence of various factors on temperature of superficial water was preliminarily analysed. Basing on these results, temperature distribution in the mentioned area was determined. Mean yearly temperatures for each station, average space temperatures on measurement days and mean yearly temperatures for the whole area of the Ezcurra Inlet were calculated.
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Abstract

Results of measurements of temperature and salinity of surface waters of the Hornsund (South Spitsbergen) carried out at a coastal point of the Isbjornhamna Bay during the winter expedition 1979/80 of the Polish Academy of Sciences are discussed. Courses of both parameters, their variability, mean values and distributions are analyzed.
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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 occurrence and temporal variations of polar shallow groundwater systems and associated seasonal springs and seeps are studied using the example of springs and seeps in the vicinity of the eastern coast of Petuniabukta in central Spitsbergen, Svalbard. Altogether, 37 groundwater outflows were documented. The outflows were mostly located at the foot of talus slopes and were characterised by small discharges (<1 dm 3 s −1 ). The water emerging from the outflows varied widely in terms of temperature and specific electrical conductivity (SpC). These outflows were supplied mainly by water from permafrost, melting snowfields and rainfall. Daily changes were studied in four of the outflows during July 2006. The observed water discharges ranged from 0.04 to 0.7 dm 3 s −1 , and the temporal variations for the particular outflows were on the order of 50% of the average value. The water temperature amplitude for particular outflows was up to 1.5 ° C. The SpC was approximately 200 μScm −1 and increased with time by almost 40 μScm −1 in the case of two outflows drain − ing talus slopes. The water emerging from two springs in carbonate and sulphate rocks had an SpC up to 1295 μScm −1 , and in one case, its increase with time was observed to be 300 μScm −1 . The increase in the SpC with time probably reflects a decrease in the contribution of snow meltwater in the groundwater recharge. Among the major local factors affecting the groundwater outflows’ water quality and discharge rate were the following: geomorphology, rock type, meteorological conditions, state of permafrost and local water storage
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Abstract

Exergy analysis of low temperature geothermal heat plant with compressor and absorption heat pump was carried out. In these two concepts heat pumps are using geothermal water at 19.5°C with spontaneous outflow 24 m3/h as a heat source. The research compares exergy efficiency and exergy destruction of considered systems and its components as well. For the purpose of analysis, the heating system was divided into five components: geothermal heat exchanger, heat pump, heat distribution, heat exchanger and electricity production and transportation. For considered systems the primary exergy consumption from renewable and non-renewable sources was estimated. The analysis was carried out for heat network temperature at 50/40°C, and the quality regulation was assumed. The results of exergy analysis of the system with electrical and absorption heat pump show that exergy destruction during the whole heating season is lower for the system with electrical heat pump. The exergy efficiencies of total system are 12.8% and 11.2% for the system with electrical heat pump and absorption heat pump, respectively.
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Abstract

The influence of external factors, temperature and flow velocity on the corrosion processes St3 in model solutions petrochemical plant recycled water with high salinity and hardness without open systems and in the presence of the inhibiting composition. It was found that an increase in temperature leads to a linear increase in corrosion rates, and the change in circulating water flow rate leads to the extreme nature of corrosion processes; optimal conditions are determined. Recommended use of cathodic inhibitors or mixed type inhibitor, in particular, the composition "SVOD-BI" (means for controlling the biological corrosion), which can significantly reduce the effect of temperature and flow on the corrosion rate St3, promotes the growth and strengthening of the oxide film in the presence of oxygen, increases the degree of protection of steel and preventing the formation of at its surface carbonate-calcium deposits.
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