Wyniki wyszukiwania - Biblioteka Nauki

1

Translocation of cations during sorption of copper in the system solution - algae (Spirogyra sp.)

100%

Rajfur M. , Kłos A. , Kříž J.

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tom Vol. 21, nr 3

425--433

EN

Kinetics of the sorption of copper cations in Spirogyra sp. algae was analysed, together with the accompanying processes of hydrogen cations sorption and releasing to the solution the cations bonded in the algae: Na+, Mg2+, K+ and Ca2+. It was established that, in a static system, at the fixed proportion of algae mass to the solution volume, these processes occur simultaneously, however presumably the quantity of the released salts influences the parameters of heterophase equilibrium of ion exchange. In the experiment conditions, the quantity of the released cations was nearly 10 times larger than the quantity of the sorbed cations. The equilibrium parameters, determined from the model of pseudo second order reaction, were compared with the parameters obtained after 30 min of the process duration, ie at relatively stable indications of measuring equipment. On the example of the sorbed copper, the difference is approximately 8%. It was confirmed that the solution conductivity is a good parameter for the estimation of the state close to equilibrium.

PL

Zbadano kinetykę procesu sorpcji kationów miedzi w glonach Spirogyra sp. oraz towarzyszące mu procesy sorpcji kationów wodorowych i procesy uwalniania do roztworu kationów związanych w glonach: Na+, Mg2+, K+ i Ca2+. Stwierdzono, że w układzie statycznym, przy stałym stosunku masy glonów do objętości roztworu, procesy te zachodzą równocześnie, przy czym należy przypuszczać, że ilość uwalnianych soli ma wpływ na parametry heterofazowej równowagi wymiany jonowej. W warunkach prowadzenia eksperymentu ilość uwolnionych kationów była blisko 10-krotnie większa niż ilość kationów sorbowanych. Porównano parametry równowagi wyznaczone z modelu reakcji pseudo-drugiego rzędu z parametrami uzyskanymi po 30 min trwania procesu, to jest przy względnie stałych wskazaniach przyrządów pomiarowych. Różnica na przykładzie sorbowanej miedzi wynosi ok. 8%. Stwierdzono, że dobrym parametrem do szacowania stanu bliskiemu stanowi równowagi jest konduktywność roztworu.

2

Estimation of radioactivity dose rate absorbed with ingested mushrooms and related health risk

88%

Dołhańczuk-Śródka A. , Ziembik Z. , Kříž J. , Hyšplerová L. , Wacławek M.

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tom Vol. 6, No. 2

499--503

EN

The fruiting bodies of fungi sprout from mycelium are capable of accumulating significant amounts of trace elements, both metals and metalloids. Content of these elements in fruiting bodies may exceed their concentration in the substrate where fungi develop. Among the elements the radioactive nuclides are also present. In this work health risk caused by increased radioactivity dose absorbed with Xerocomus badius bay bolete consumption was estimated. In analysis concentrations of radioactive isotopes 137Cs and 40K were taken into consideration. It was found that moderate ingestion of bay bolete does not create health risk due to increased radioactive substances intake. The amount of consumed mushrooms that could deliver the dose exceeding the safe one, is rather improbable in real life.

PL

Owocniki grzybów wyrastające z grzybni są zdolne do gromadzenia znacznych ilości pierwiastków śladowych zarówno metali, jak i niemetali. Zawartość tych pierwiastków w owocnikach może wielokrotnie przekroczyć ich stężenia w podłożu. Wśród pochłoniętych pierwiastków są również nuklidy promieniotwórcze. Dokonano oceny potencjalnych dawek skutecznych promieniowania gamma w wyniku wchłonięcia 137Cs i 40K wraz ze spożywanym grzybem. Na podstawie wyników pomiarów stwierdzono, że umiarkowane spożycie podgrzybka brunatnego nie stwarza zagrożenia dla zdrowia ze względu na zwiększone spożycie substancji radioaktywnych.

3

Pb-210 isotope as a pollutant emission indicator

88%

Dołhańczuk-Śródka A. , Ziembik Z. , Kříž J. , Hyšplerova L. , Wacławek M.

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2015

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tom Vol. 22, nr 1

73--81

EN

Passive biomonitoring using 210Pb was used in the paper to evaluate pollutant deposition. Well-developed epiphytic foliose lichens Hypogymnia physodes growing on spruce branches were used in the studies. The samples of mosses Pleurozium schreberi and soil (raw humus) were collected from the area around the tree from which the samples of lichens were collected. The studies have shown that it is possible to identify dust emission sources using a radioactive lead isotope (210Pb). The highest activity of 210Pb was observed in areas with increased deposition of other pollutants, such as Ni, Cd, Cu and Pb, which may indicate that 210Pb is one of the emission components.

PL

W pracy zastosowano biomonitoring pasywny, z wykorzystaniem 210Pb, do oceny depozycji zanieczyszczeń. Do badań wykorzystano dobrze wykształcone epifityczne porosty listkowate Hypogymnia physodes, porastające gałęzie świerka. Wokół drzewa, z którego pobrano próbki porostów, pobierano próbki mchów Pleurozium schreberi oraz gleby - próchnicy nadkładowej. W prowadzonych badaniach stwierdzono, że możliwa jest identyfikacja źródeł emisji pyłu przy wykorzystaniu radioaktywnego izotopu ołowiu - 210Pb. Największe aktywności 210Pb zaobserwowano na terenach o zwiększonej depozycji innych zanieczyszczeń, np. Ni, Cd, Cu i Pb, co może wskazywać, że 210Pb jest jednym z komponentów emisji.

4

Influence green sand system by core sand additions

88%

Špirutová N. , Beňo J. , Bednářová V. , Kříž J. , Kandrnál M.

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tom Vol. 12, iss. 1

105-110

EN

Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron) are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: 'How the green sand systems are influenced by core sands?" This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50%. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition). Ratio of active betonite by Methylene blue test was also determined.

5

Modelling of Mercury Emissions from Large Solid Fuel Combustion and Biomonitoring in CZ-PL Border Region

51%

Kříž J. , Loskot J. , Štěpánek V. , Hyšplerová L. , Jezbera D. , Trnková L. , Dołhańczuk-Śródka A. , Ziembik Z. , Rajfur M. , Kłos A. , Wacławek M.

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tom Vol. 23, nr 4

593--604

EN

Tightening of norms for air protection leads to a development of new and significantly more effective techniques for removing particulate matter, SOx and NOx from flue gas which originates from large solid fuel combustion. Recently, it has been found that combinations of these environmental technologies can also lead to the reduction of mercury emissions from coal power plants. Now the greatest attention is paid especially to the coal power plant in Opatovice nad Labem, close to Hradec Kralove. Its system for flue gas dedusting was replaced by a modern type of cloth fabric filter with the highest particle separation efficiency which belongs to the category of BAT. Using this technology, together with modernization of the desulphurisation device and increasing of nitrogen oxides removal efficiency, leads also to a reduction of mercury emissions from this power plant. The University of Hradec Kralove, the Opole University and EMPLA Hradec Kralove successfully cooperate in the field of toxic metals biomonitoring almost 20 years. In the Czech-Polish border region, comprehensive biomonitoring of mercury in bioindicators Xerocomus badius in 9 long-term monitored reference points is done. The values of mercury concentration measured in 2012 and 2016 were compared with values computed by a dispersion model SYMOS′97 (updated 2014). Thanks to modern methods of dedusting and desulphurisation, emissions of mercury from this large coal power plant are now smaller than before and that the downward trends continues. The results indicate that Xerocomus badius is a suitable bioindicator for a long-term monitoring of changes in mercury imissions in this forested border region. This finding is significant because it shows that this region is suitable for leisure, recreation, and rehabilitation.