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EN
We analyse the factors used for assessing groundwater intrinsic vulnerability to pollution in the mean residence time estimation method, providing a final vulnerability evaluation. The following factors were analysed: depth to shallow groundwater, effective precipitation infiltration coefficient, terrain inclination, volumetric water content of soils and rocks in the unsaturated zone and volumetric water content of the topsoil. GIS surveys were performed for two geomorphologically diverse regions: a highland piedmont and a lowland plain in Poland (Central Europe). In both cases, groundwater had spatially diverse vulnerability to contamination. The research method used relied on determining the percentage participation of the area with particular values of the parameters analysed in areas of different degrees of vulnerability. Knowledge of the extent and distribution of variability of the parameters analysed in areas of particular degrees of vulnerability helps explain the causes of spatial variation in groundwater intrinsic vulnerability to contamination in given areas.
EN
The points of the national network of groundwater monitoring comprise a stable benchmarks in quality and quantity monitoring. The obtained data (tritium and δ18O) are important for understanding the groundwater cycling and are indirect indicators of aquifer vulnerability to anthropogenic pollution. The goal of this paper is to present the relation of the tritium content and delta value of stable isotopes of oxygen against the groundwater sampling depth in 2004–2012. It is demonstrated that the remains of “nuclear” tritium concentration is still present in groundwater as a tritium peak at depths around 30 m. Determination of dynamics of recharge in groundwater bodies, based on national network observation points is associated to the estimation of the groundwater residence time in aquifers and remains one the vital problem of hydrogeology.
3
Content available remote Badanie kinetyki mielenia węgla energetycznego metodą atomów znaczonych
PL
Artykuł przedstawia wyniki oznaczenia czasów przebywania wybranych klas ziarnowych węgla energetycznego w młynie za pomocą metody atomów znaczonych. Wykazano, że czas przebywania węgla w młynach pierścieniowo-kulowych z wewnętrznymi zawrotami jest wprost proporcjonalny do wielkości ziarna nadawy. Wykazano możliwość wykorzystania rezultatów uzyskanych w wyniku badania procesu mielenia za pomocą metody znaczników promieniotwórczych dla określenie kinetyki rozdrobnienia węgla w młynie. Wyznaczone modele kinetyki mielenia klas ziarnowych węgla są podstawą optymalizacji przemysłowego procesu mielenia węgla w energetyce zawodowej.
EN
The article presents the results of determination of the residence time of selected size grades of power coal in the grinding mill by means of the labelled atom method. It has been shown that the residence time of coal in ring-ball mills is directly proportional to the size of feed grain. The possibility has been pointed out to use the results obtained in consequence of the grinding process testing by means of the radioactive marker method in order to determine the coal size reduction kinetics in the mill. The determined models of grinding kinetics of coal grain classes are the basis of optimization of the industrial coal grinding process in the professional power industry.
PL
Mapy podatności naturalnej wód podziemnych na zanieczyszczenia stanowią wizualizację oceny podatności wód podziemnych na zanieczyszczenia. Są one jednym z najważniejszych elementów uwzględnianych przy podejmowaniu decyzji odnośnie zagospodarowania terenu i obiektów potencjalnie uciążliwych dla środowiska. Badania podatności wód podziemnych na zanieczyszczenia zostały przeprowadzone na obszarze Kampinoskiego Parku Narodowego (skala regionalna) oraz na wytypowanym poligonie w pobliżu Wiktorowa w Kampinoskim Parku Narodowym (około 30 km2) w skali lokalnej. Ocenę podatności naturalnej przeprowadzono przy zastosowaniu zmodyfikowanej metody DRASTIC oraz na podstawie szacunku czasu przesączania się zanieczyszczeń konserwatywnych. Uzyskane rezultaty wskazują, że rezultat oceny zależy od wykorzystanej metody, stopnia rozpoznania warunków hydrogeologicznych, zastosowanych uproszczeń oraz wyznaczonego celu badań.
EN
Maps of natural groundwater vulnerability to contamination illustrate the assessment of natural groundwater vulnerability. They are also one of the important components that are taken into consideration while making a decision as regards the site management and objects potentially troublesome for the environment. The researches of natural vulnerability were conducted for the area of the Kampinoski National Park (on a regional scale) and for the area (about 30 km2) near Wiktorów (part of the Kampinos National Park) on a local scale. The assessment of vulnerability has been performed with the use of the modified DRASTIC method and calculations of the time migration method of a contaminant through the unsaturated zone. The results of the study indicate that the evaluation of natural groundwater vulnerability to contamination depends on the following factors: research methodology, degree of area recognition, applied simplifications and the purpose of research.
5
Content available remote Unusual Baltic inflow activity in 2002-2003 and varying deep-water properties
EN
The unusual sequence of inflow events into the Baltic Sea that occurred in 2002 and 2003 includes the first ever important baroclinic inflow to be described (August 2002), the Major Baltic Inflow (January 2003), which gave rise to the highest oxygen levels in the Gotland Deep since the 1930s, and the baroclinic inflow (August 2003) that elevated the Gotland Basin deep water salinity to values last observed in 1977, and caused the surface salinity to rise again. From these trend changes, salt residence times were estimated at about 20 years in the deep waters and 30 years above the pycnocline. Ventilation of the remote Karlsö Deep took until 2005, two years after the inflow event responsible, at a time when the Bornholm and Eastern Gotland Basins were already returning to stagnation.
EN
Aquifer vulnerability maps are valuable tools for communicating concerns about the level of groundwater pollution hazard to local landuse planners and to the general public. Groundwater vulnerability to contamination in the Kampinoski National Park (KNP) area in central Poland was evaluated as a basis for developing appropriate protection strategy for the groundwater resources and management in recreation areas located near Warsaw. Assessment was accomplished using U.S. EPA DRASTIC and the residence time in the unsaturated zone of a conservative pollutant. The final DRASTIC values have been grouped into medium (37 % of area) and medium high (52 %) intrinsic vulnerability categories. The residence time in the unsaturated zone is classified in 11 intervals, ranging from 30 days to 30 years, but nearly 75 % of the study area is characterized by intervals from 1 to 3 years.
7
PL
Na podstawie artykułu [1] w niniejszej pracy przedstawiono wyprowadzenie wzorów na określenie czasu przebywania kryształów oraz całkowitego czasu przebywania dla procesu krystalizacji fluidalnej w przypadku idealnej klasyfikacji.
EN
On the basis of [1] a derivation of formulae for the crystals residence time and overall residence time within the fluidised-bed crystallizer with ideal classification is presented.
EN
A three-dimensional baroclinic sigma-coordinate model was applied to study the circulation and thermohaline variability in the coastal zone in the south-eastern Baltic Sea. The model is based on the Princeton Ocean Model code of Blumberg & Mellor (1987), known as POM, and has the horizontal resolution of ~5 km and 24 sigma-levels in the vertical. The hydrodynamic conditions and variability of water and salt exchange between the Gulf of Gdansk and the Baltic Proper, and the renewal of water masses in the Gulf of Gdansk due to atmospheric forcing are analyzed. The numerical simulations were performed with real atmospheric forcings as well as with homogeneous (spatially uniform) wind fields over the whole Baltic Sea. The numerical simulations showed that the atmospheric forcing (winds) can play a significant role in shaping the renewal of bottom saline waters in the Gulf of Gdansk. Two regions of inflow/outflow of saline waters responsible for the salinity regime were located. The overall water exchange between the Gulf and the Baltic Proper as well as the exchange of saline bottom waters appear to be strongly dependent on wind conditions. The net flux of water of salinity >9 PSU is of the order of 48000-100000 m3 s-1. SE, E, S and NE winds were found to exert the greatest influence on salinity conditions in the Gulf of Gdansk. Estimates of saline (salinity >9 PSU) water residence time based on the model simulation yielded values from 46 days for SE winds to 153 days for NW winds.
EN
Measurement results of barium sulphate reaction crystallization kinetics are presented. Experiments were carried out in the crystallizer with an internal circulation of suspension. The crystallizer was continuously fed with barium chloride solution (of concentration 24.0 mass %) and stoichiometrically crystalline ammonium sulphate. The rates of BaSO4 nucleation and crystal growth were estimated from crystal size distribution according to calculation procedure for the MSMPR crystallizer. Research results may be utilized in the technology of post quenching salts processing.
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